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Sample records for saline domes caracterizacion

  1. Characterization of the rock salt for the design of underground storage in saline domes; Caracterizacion de la roca sal-gema para el diseno de almacenamientos en domos salinos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Meyenberg, Lucia [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1987-12-31

    The saline domes are natural geological formations, that have been formed in the underground, through the passage of millions of years. In Europe, they are used for hydrocarbon storage; for instance France is planning to increase, in a short term, its crude storing capacity in domes of 5 to 10 millions cubic meters (60 million of barrel), holding capacity. Additionally, studies are being conducted on the stability of this type of domes, for the storage of nuclear wastes during 100 thousand or 1 million years. [Espanol] Los domos salinos son formaciones geologicas estructurales naturales, que se han constituido en el subsuelo, en el transcurso de millones de anos. En Europa, se aprovechan para almacenar hidrocarburo; por ejemplo, Francia planea aumentar, a corto plazo, su capacidad de almacenamiento de crudo en domos de 5 a 10 millones de metros cubicos (60 millones de barriles). Ademas, se realizan estudios de estabilidad en este tipo de domos, para almacenar desechos nucleares durante 100 mil o 1 millon de anos.

  2. Talar Dome Lesion

    Science.gov (United States)

    ... Please enable Javascript in your browser. Talar Dome Lesion What Is a Talar Dome Lesion? The ankle joint is composed of the bottom ... on the specific case. Complications of Talar Dome Lesions Depending on the amount of damage to the ...

  3. Millennium Dome publikupuuduses

    Index Scriptorium Estoniae

    2000-01-01

    Londoni Millennium Dome toob iga nädal umbes 7 miljonit krooni kahjumit. Valitsusel on plaanis laenata Dome'ile 60 miljonit naela. Jennie Page'i asemele kutsuti direktoriks Pariisi Eurodisney juht Pierre-Yves Gerbeau. Inglise riiklike muuseumide ja kunstigaleriide tasuta külastatavaks muutmine alates aastast 2002 jääb ära.

  4. LIGHTWEIGHT AND TRANSPARENT DOMES

    Directory of Open Access Journals (Sweden)

    Izis Salvador Pinto

    2012-11-01

    Full Text Available Domes have existed for centuries, from ancient domed structures such as Igloos to contemporary domes such as the Eden Project. However, over the years there has been a gradual shift in construction of long-span domes, from the use of opaque and heavy materials, to the use of transparent and lightweight structures. The development in material technology provides the opportunity to reduce the weight of materials and structures to be lightweight and highstrength, saving energy, fuel, and contributing to the low carbon agenda. The progress in materials science and the evolution in the technology of construction and manufacturing in architecture make the utopian ideas of the past into a reality. Domes with Ethylene tetrafluoroethylene (ETFE cushions as cladding system are lightweight and transparent structures. ETFE is a cost-effective, environmentally friendly material. The advantages of ETFE, compared to glass, is that ETFE is one per cent of the weight of glass, transmits more light and costs far less to instal. Furthermore, this material does not degrade under ultraviolet light and is unaffected by atmospheric pollutants. This paper presents an overview of contemporary long-span domes constructed with lightweight materials, from the domes in buildings, to the possibility of achieving large city-dome enclosures.

  5. Caracterizacion neuropsicologica de la impulsividad funcional y disfuncional en adictos a sustancias: implicaciones clinicas

    National Research Council Canada - National Science Library

    Pedrero-Perez, Eduardo J; Ruiz Sanchez de Leon, Jose M; Rojo Mota, Gloria; Llanero Luque, Marcos; Puerta Garcia, Carmen

    2012-01-01

    ..., orientadas a metas, mediante un proceso de toma de decisiones con riesgo calculado. Pocos estudios han abordado la caracterizacion neuropsicologica de ambas variantes, relacionandolas con el rendimiento en pruebas clasicas...

  6. Pumping systems characterization; Caracterizacion de los sistemas de bombeo

    Energy Technology Data Exchange (ETDEWEB)

    Torres Gutierrez, R. [Eficiencia Energetica, S.A. de C.V., Mexico, D. F. (Mexico)

    1995-12-31

    In this paper the characterization of the pumping systems is discussed, and an explanation is given of the need of evaluating in detail the possibility of implementing the frequency variators as an option for energy conservation, explaining how the simple use of the similarity or affinity laws lead to over-estimate the saving. [Espanol] En este articulo se describe la caracterizacion de los sistemas de bombeo y se explica la necesidad de evaluar en detalle la posibilidad de implementacion de variadores de frecuencia, como una alternativa para el ahorro de energia, explicando como el simple uso de las leyes de semejanza o afinidad llevan a sobre-evaluar los ahorros.

  7. Studies of the suitability of salt domes in east Texas basin for geologic isolation of nuclear wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kreitler, C.W.

    1979-01-01

    The suitability of salt domes in the east Texas basin (Tyler basin), Texas, for long-term isolation of nulear wastes is being evaluated. The major issues concern hydrogeologic and tectonic stability of the domes and potential natural resources in the basin. These issues are being approached by integration of dome-specific and regional hydrogeolgic, geologic, geomorphic, and remote-sensing investigations. Hydrogeologic studies are evaluating basinal hydrogeology and ground-water flow around the domes in order to determine the degree to which salt domes may be dissolving, their rates of solution, and the orientation of saline plumes in the fresh-water aquifers. Subsurface geologic studies are being conducted: (1) to determine the size and shape of specific salt domes, the geology of the strata immediately surrounding the domes, and the regional geology of the east Texas basin; (2) to understand the geologic history of dome growth and basin infilling; and (3) to evaluate potential natural resources. Geomorphic and surficial geology studies are determining whether there has been any dome growth or tectonic movement in the basin during the Quaternary. Remote-sensing studies are being conducted to determine: (1) if dome uplift has altered regional lineation patterns in Quaternary sediments; and (2) whether drainage density indicates Quaternary structural movement. On the basis of the screening criteria of Brunton et al (1978), Oakwood and Keechi domes have been chosen as possible candidate domes. Twenty-three domes have been eliminated because of insufficient size, too great a depth to salt, major hydrocarbon production, or previous use (such as liquid propane storage or salt mining or brining). Detailed geologic, hydrogeologic, and geomorphic investigations are now being conducted around Oakwood and Keechi salt domes. (JMT)

  8. Lunar domes properties and formation processes

    CERN Document Server

    Lena, Raffaello; Phillips, Jim; Chiocchetta, Maria Teresa

    2013-01-01

    Lunar domes are structures of volcanic origin which are usually difficult to observe due to their low heights. The Lunar Domes Handbook is a reference work on these elusive features. It provides a collection of images for a large number of lunar domes, including telescopic images acquired with advanced but still moderately intricate amateur equipment as well as recent orbital spacecraft images. Different methods for determining the morphometric properties of lunar domes (diameter, height, flank slope, edifice volume) from image data or orbital topographic data are discussed. Additionally, multispectral and hyperspectral image data are examined, providing insights into the composition of the dome material. Several classification schemes for lunar domes are described, including an approach based on the determined morphometric quantities and spectral analyses. Furthermore, the book provides a description of geophysical models of lunar domes, which yield information about the properties of the lava from which the...

  9. Foldable dome climate measurements and thermal properties

    Science.gov (United States)

    Sliepen, Guus; Jägers, Aswin P. L.; Hammerschlag, Robert H.; Bettonvil, Felix C. M.

    2010-07-01

    As part of a larger project for measuring various aspects of foldable domes in the context of EST and with support of the Dutch Technology Foundation STW, we have collected over a year of continuous temperature and humidity measurements, both inside and outside the domes of the Dutch Open Telescope (DOT) on La Palma5 and the GREGOR telescope on Tenerife.6 In addition, we have measured the wind field around each dome. Although the structure of both domes is similar, the DOT dome has a single layer of cloth, and is situated on top of an open tower. In contrast, the GREGOR dome has a double layer of cloth, and is situated on top of a tower-shaped building. These differences result in large differences in temperature and humidity insulation when the dome is closed. We will present the changes in temperature and humidity one can expect for each dome within one day, and the statistics for the variations throughout a year. In addition, we will show that the main advantage of a foldable dome is the near instantaneous equilibration of the air inside the volume originally enclosed by the dome and that of the environment outside the dome. This property allows one to operate a telescope without needing expensive air conditioning and dome skin temperature control in order to limit dome and shell seeing effects. The measurements give also information about the weather fluctuations at the sites of the domes. It was observed that on small time scales the temperature fluctuations are significantly greater during the day than during the night.

  10. What factors control superficial lava dome explosivity?

    Science.gov (United States)

    Boudon, Georges; Balcone-Boissard, Hélène; Villemant, Benoît; Morgan, Daniel J

    2015-09-30

    Dome-forming eruption is a frequent eruptive style and a major hazard on numerous volcanoes worldwide. Lava domes are built by slow extrusion of degassed, viscous magma and may be destroyed by gravitational collapse or explosion. The triggering of lava dome explosions is poorly understood: here we propose a new model of superficial lava-dome explosivity based upon a textural and geochemical study (vesicularity, microcrystallinity, cristobalite distribution, residual water contents, crystal transit times) of clasts produced by key eruptions. Superficial explosion of a growing lava dome may be promoted through porosity reduction caused by both vesicle flattening due to gas escape and syn-eruptive cristobalite precipitation. Both processes generate an impermeable and rigid carapace allowing overpressurisation of the inner parts of the lava dome by the rapid input of vesiculated magma batches. The relative thickness of the cristobalite-rich carapace is an inverse function of the external lava dome surface area. Explosive activity is thus more likely to occur at the onset of lava dome extrusion, in agreement with observations, as the likelihood of superficial lava dome explosions depends inversely on lava dome volume. This new result is of interest for the whole volcanological community and for risk management.

  11. Salinization and Saline Environments

    Science.gov (United States)

    Vengosh, A.

    2003-12-01

    One of the most conspicuous phenomena of water-quality degradation, particularly in arid and semi-arid zones, is salinization of water and soil resources. Salinization is a long-term phenomenon, and during the last century many aquifers and river basins have become unsuitable for human consumption owing to high levels of salinity. Future exploitation of thousands of wells in the Middle East and in many other water-scarce regions in the world depends, to a large extent, on the degree and rate of salinization. Moreover, every year a large fraction of agricultural land is salinized and becomes unusable.Salinization is a global environmental phenomenon that affects many different aspects of our life (Williams, 2001a, b): changing the chemical composition of natural water resources (lakes, rivers, and groundwater), degrading the quality of water supply to the domestic and agriculture sectors, contribution to loss of biodiversity, taxonomic replacement by halotolerant species ( Williams, 2001a, b), loss of fertile soil, collapse of agricultural and fishery industries, changing of local climatic conditions, and creating severe health problems (e.g., the Aral Basin). The damage due to salinity in the Colorado River Basin alone, for example, ranges between 500 and 750 million per year and could exceed 1 billion per year if the salinity in the Imperial Dam increases from 700 mg L-1 to 900 mg L-1 (Bureau of Reclamation, 2003, USA). In Australia, accelerating soil salinization has become a massive environmental and economic disaster. Western Australia is "losing an area equal to one football oval an hour" due to spreading salinity ( Murphy, 1999). The annual cost for dryland salinity in Australia is estimated as AU700 million for lost land and AU$130 million for lost production ( Williams et al., 2002). In short, the salinization process has become pervasive.Salinity in water is usually defined by the chloride content (mg L-1) or total dissolved solids content (TDS, mg L-1or g

  12. Characterization of a complex hydrogeological system under extren density variability: Fuente de Piedra lake (Malaga, Spain). Connection with an hyper saline regional karstic system; Caracterizacion de un sistema hidrogeologico complejo con variabilidad extrema de la densidad: Laguna de Fuente de Piedra (Malaga). Vinculacion con un sistema karstico regional hipersalino

    Energy Technology Data Exchange (ETDEWEB)

    Heredia, J.; Ruiz, J. M.; Garcia de Domingo, A.

    2009-07-01

    Fuente de Piedra lake declared as a Nature Reserve- was one of the first Spanish wetlands to be incorporated into the Ramsar Convention and it is a nesting site for the largest flamingo colonies in the western Mediterranean, after the Camargue wetland in France. Sustainable water management is basic in conservation strategy of the Nature Reserve, so that numerical model will be a useful tool. Fuente de Piedra lake system (Malaga) is characterized by a great hydrogeological complexity. Groundwater flow takes place by means of stratified flow systems due to the existence of marked density contrasts between fresh groundwater, brackish waters, subsurface brines and hypersaline regional karst brines. Groundwater flows and surface runoff discharge into an endorheic basin lake, supporting the wetland. Subsurface brine reaches a TDS value about five times that of seawater and hyper saline regional karst brines is still one order of magnitude larger than that. Finally, it proposes a conceptual model that integrates information from different sources and it explains many observations that other conceptual models cant do it. (Author) 32 refs.

  13. PERSIAN DOMES: HISTORY, MORPHOLOGY AND TYPOLOGIES

    Directory of Open Access Journals (Sweden)

    Maryam Ashkan

    2009-11-01

    Full Text Available Persian master builders had introduced an architectural innovation which had an imperishable effect on dome architecture in the Middle East and Central Asia: surmounting a dome on squinches. This paper aims to provide a broader perspective of Persian domes as the most significant feature of Eastern domes in the Middle East. As opposed to previous general historic studies, this paper introduces a new analytical approach directed towards analysis of architectural concepts and stylistic attributes of Persian domes based on an epistemological premise of their space syntax. By analytic reviewing of examples, the paper addresses the origin of Persian domes, their formal morphological constitutions, and their typological forms based on the diversity of the external shell over the specific timeline, from the pre-Islamic era through the Qajar period in Iran. The study of the Persian dome’s characteristics can illustrate undiscovered information about the essences of developing dome constructions in the Middle East. It can also establish new design standards regarding the frameworks of domical building configurations to be used for creating typological diversity in dome design and to renew the morphological principles of the traditional dome compositions in contemporary architectural designs. Finally, the insights gained can inform conservation efforts on domical structures in the region and elsewhere.

  14. Environmental assessment: Richton Dome site, Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1986-05-01

    In February 1983, the US Department of Energy (DOE) identified the Richton Dome site in Mississippi as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Richton Dome site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EAs. The site is in the Gulf interior region, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains two other potentially acceptable sites--the Cypress Creek Dome site in Mississippi and the Vacherie Dome site in Louisiana. Although the Cypress Creek Dome and the Vacherie Dome sites are suitable for site characterization, the DOE has concluded that the Richton Dome site is the preferred site in the Gulf interior region. On the basis of the evaluations reported in this EA, the DOE has found that the Richton Dome site is not disqualified under the guidelines.

  15. Environmental assessment: Richton Dome Site, Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1986-05-01

    In February 1983, the US Department of Energy (DOE) identified the Richton Dome site in Mississippi as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Richton Dome site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EAs. The site is in the Gulf interior region, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains two other potentially acceptable sites--the Cypress Creek Dome site in Mississippi and the Vacherie Dome site in Louisiana. Although the Cypress Creek Dome and the Vacherie Dome sites are suitable for site characterization, the DOE has concluded that the Richton Dome site is the preferred site in the Gulf interior region. On the basis of the evaluations reported in this EA, the DOE has found that the Richton Dome site is not disqualified under the guidelines.

  16. A new procedure of percutaneous microwave coagulation therapy under artificial hydrothorax for patients with liver tumors in the hepatic dome.

    Science.gov (United States)

    Shimada, S; Hirota, M; Beppu, T; Shiomori, K; Marutsuka, T; Matsuo, A; Tanaka, E; Ogawa, M

    2001-01-01

    Percutaneous microwave coagulation therapy (PMCT) has been widely used as an effective minimal invasive therapy for small liver tumors. The occurrence of a sonographic masked space due to the presence of the lung, however, has become a major obstacle to visualizing the whole tumor in the hepatic dome. To facilitate the use of PMCT for liver tumors in the hepatic dome, we developed PMCT in combination with the artificial hydrothorax method (percutaneous transdiaphragmatic MCT: PTD-MCT). Our new approach for PMCT to the hepatic tumors located in Couinaud's segments VIII or VII just under the diaphragm resulted in a successful treatment. The separation of the lung from the diaphragm by the infusion of saline into the pleural cavity enabled us not only to visualize the whole tumor in the hepatic dome to accurately target the tumor, but also helped us to avoid injuring the lung. PTD-MCT is therefore strongly recommended for the treatment of liver tumors in the hepatic dome.

  17. Autonomous Dome for a Robotic Telescope

    Science.gov (United States)

    Kumar, A.; Sengupta, A.; Ganesh, S.

    2016-12-01

    The Physical Research Laboratory operates a 50 cm robotic observatory at Mount Abu (Rajsthan, India). This Automated Telescope for Variability Studies (ATVS) makes use of the Remote Telescope System 2 (RTS2) for autonomous operations. The observatory uses a 3.5 m dome from Sirius Observatories. We have developed electronics using Arduino electronic circuit boards with home grown logic and software to control the dome operations. We are in the process of completing the drivers to link our Arduino based dome controller with RTS2. This document is a short description of the various phases of the development and their integration to achieve the required objective.

  18. Emplacement Scenarios for Volcanic Domes on Venus

    Science.gov (United States)

    Glaze, Lori S.; Baloga, Steve M.; Stofan, Ellen R.

    2012-01-01

    One key to understanding the history of resurfacing on Venus is better constraints on the emplacement timescales for the range of volcanic features visible on the surface. A figure shows a Magellan radar image and topography for a putative lava dome on Venus. 175 such domes have been identified with diameters ranging from 19 - 94 km, and estimated thicknesses as great as 4 km. These domes are thought to be volcanic in origin and to have formed by the flow of viscous fluid (i.e., lava) on the surface.

  19. Pressure Dome for High-Pressure Electrolyzer

    Science.gov (United States)

    Norman, Timothy; Schmitt, Edwin

    2012-01-01

    A high-strength, low-weight pressure vessel dome was designed specifically to house a high-pressure [2,000 psi (approx. = 13.8 MPa)] electrolyzer. In operation, the dome is filled with an inert gas pressurized to roughly 100 psi (approx. = 690 kPa) above the high, balanced pressure product oxygen and hydrogen gas streams. The inert gas acts to reduce the clamping load on electrolyzer stack tie bolts since the dome pressure acting axially inward helps offset the outward axial forces from the stack gas pressure. Likewise, radial and circumferential stresses on electrolyzer frames are minimized. Because the dome is operated at a higher pressure than the electrolyzer product gas, any external electrolyzer leak prevents oxygen or hydrogen from leaking into the dome. Instead the affected stack gas stream pressure rises detectably, thereby enabling a system shutdown. All electrical and fluid connections to the stack are made inside the pressure dome and require special plumbing and electrical dome interfaces for this to be accomplished. Further benefits of the dome are that it can act as a containment shield in the unlikely event of a catastrophic failure. Studies indicate that, for a given active area (and hence, cell ID), frame outside diameter must become ever larger to support stresses at higher operating pressures. This can lead to a large footprint and increased costs associated with thicker and/or larger diameter end-plates, tie-rods, and the frames themselves. One solution is to employ rings that fit snugly around the frame. This complicates stack assembly and is sometimes difficult to achieve in practice, as its success is strongly dependent on frame and ring tolerances, gas pressure, and operating temperature. A pressure dome permits an otherwise low-pressure stack to operate at higher pressures without growing the electrolyzer hardware. The pressure dome consists of two machined segments. An O-ring is placed in an O-ring groove in the flange of the bottom

  20. The Longevity of Lava Dome Eruptions

    CERN Document Server

    Wolpert, Robert L; Calder, Eliza S

    2015-01-01

    Understanding the duration of past, on-going and future volcanic eruptions is an important scientific goal and a key societal need. We present a new methodology for forecasting the duration of on-going and future lava dome eruptions based on a database (DomeHaz) recently compiled by the authors. The database includes duration and composition for 177 such eruptions, with "eruption" defined as the period encompassing individual episodes of dome growth along with associated quiescent periods during which extrusion pauses but unrest continues. In a key finding we show that probability distributions for dome eruption durations are both heavy-tailed and composition-dependent. We construct Objective Bayes statistical models featuring heavy-tailed Generalized Pareto distributions with composition-specific parameters to make forecasts about the durations of new and on-going eruptions that depend on both eruption duration-to-date and composition. Our Bayesian predictive distributions reflect both uncertainty about mode...

  1. Indicators: Salinity

    Science.gov (United States)

    Salinity is the dissolved salt content of a body of water. Excess salinity, due to evaporation, water withdrawal, wastewater discharge, and other sources, is a chemical sterssor that can be toxic for aquatic environments.

  2. Holodeck: Telepresence Dome Visualization System Simulations

    Science.gov (United States)

    Hite, Nicolas

    2012-01-01

    This paper explores the simulation and consideration of different image-projection strategies for the Holodeck, a dome that will be used for highly immersive telepresence operations in future endeavors of the National Aeronautics and Space Administration (NASA). Its visualization system will include a full 360 degree projection onto the dome's interior walls in order to display video streams from both simulations and recorded video. Because humans innately trust their vision to precisely report their surroundings, the Holodeck's visualization system is crucial to its realism. This system will be rigged with an integrated hardware and software infrastructure-namely, a system of projectors that will relay with a Graphics Processing Unit (GPU) and computer to both project images onto the dome and correct warping in those projections in real-time. Using both Computer-Aided Design (CAD) and ray-tracing software, virtual models of various dome/projector geometries were created and simulated via tracking and analysis of virtual light sources, leading to the selection of two possible configurations for installation. Research into image warping and the generation of dome-ready video content was also conducted, including generation of fisheye images, distortion correction, and the generation of a reliable content-generation pipeline.

  3. Optical Sky Brightness at Dome C, Antarctica

    Science.gov (United States)

    Kenyon, S.; Storey, J. W. V.; Burton, M. G.

    2006-08-01

    Dome C, Antarctica is a prime site for astronomical observations in terms of climate, wind speeds and turbulence. The infrared and terahertz sky backgrounds are the lowest of any inhabited place on Earth. However, at present little is known about the optical sky brightness and atmospheric extinction. Using a variety of modelling techniques together with data from the South Pole, we estimate the brightness of the night sky including the contributions from scattered sunlight, moonlight, aurorae, airglow, zodiacal light and artificial sources. We compare our results to another prime astronomical site, Mauna Kea. We find moonlight has significantly less effect at Dome C than at Mauna Kea. Aurorae are expected to have a minor impact at both sites, and zodiacal light is expected to be less at Dome C than at Mauna Kea. Airglow emissions at Dome C are expected to be similar to those at temperate sites. With proper planning, artificial sources of light pollution should be non-existent. The overall atmospheric extinction, or opacity, is expected to be the minimum possible. We conclude that Dome C is a very promising site not only for infrared and terahertz astronomy, but for optical astronomy as well..

  4. The research of suspen-dome structure

    Science.gov (United States)

    Gong, Shengyuan

    2017-09-01

    After overcoming the shortcomings of single-layer latticed shell and cable dome structure, the suspen-dome was developed by inheriting the advantages of them, and it was recognized and applied as a new type of prestressed force large span space structure. Based on the analysis of the background and mechanical principle, the researches of suspen-dome are reviewed, including form-finding analysis, the analysis of static force and stability, the dynamic behaviors and the earthquake resistant behavior, the analysis of prestressing force and optimization design, and the research status of the design of the fir-resistant performance etc. This thesis summarizes the methods of various researches, being a reference for further structural performance research and structural engineering application.

  5. Environmental assessment, Richton Dome site, Mississippi (US)

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1986-05-01

    The Nuclear Waste Policy Act of 1982 (42 USC Sections 10101-10226) requires the environmental assessment of a potential site to include a statement of the basis for the nomination of a site as suitable for characterization. Volume 2 of this environmental assessment provides a detailed evaluation of the Richton Dome Site and its suitability as the site for a radioactive waste disposal facility under DOE siting guidelines, as well as a comparison of the Richton Dome site with other proposed sites. Evaluation of the Richton Dome site is based on the reference repository design, but the evaluation will not change if based on the Mission Plan repository concept. The comparative evaluation of proposed sites is required under DOE guidelines, but is not intended to directly support the subsequent recommendation of three sites for characterization as candidate sites. 428 refs., 24 figs., 62 tabs. (MHB)

  6. Talar dome fracture repaired using bioabsorbable fixation.

    Science.gov (United States)

    Zelent, Marek E; Neese, David J

    2006-01-01

    We describe a man with an acute osteochondral defect in the lateral talar dome associated with a supination-adduction-type ankle fracture. The osteochondral defect was readily visible on plain film radiographs, and magnetic resonance imaging was ordered to determine the full extent of soft-tissue and articular injury. It was discovered that the patient had a stage IV lesion of the talar dome, with complete inversion of the fragment, and rupture of the anterior talofibular and calcaneofibular lateral ankle ligaments. Furthermore, the patient experienced an oblique fracture of the medial malleolus with comminution. The talar dome lesion was surgically reduced and fixated using bioabsorbable pins. Nine months after surgery, the patient was fully recovered from his injury and had no functional limitations.

  7. Experiments in connection with Salt Domes

    NARCIS (Netherlands)

    Escher, B.G.; Kuenen, Ph.H.

    1928-01-01

    The different theories concerning the origin of Salt Domes in Roumania, Germany, Texas, Louisiana, Colorado and Utah are discussed. In Roumania the salt occurs in cores of “Diapir” anticlines. The existance of hills of salt indicates, that the salt is still pushing upwards. In Germany the salt

  8. Salinity Energy.

    Science.gov (United States)

    Schmitt, Walter R.

    1987-01-01

    Discussed are the costs of deriving energy from the earth's natural reserves of salt. Argues that, as fossil fuel supplies become more depleted in the future, the environmental advantages of salinity power may prove to warrant its exploitation. (TW)

  9. consistencia en dome: un caso de estudio

    Directory of Open Access Journals (Sweden)

    DANIEL CABARCAS

    2006-01-01

    Full Text Available Las herramientas metaCASE ofrecen una funcionalidad similar a la de las herramientas CASE convencionales para notaciones gráficas arbitrarias, una vez estas notaciones le sean especificadas adecuadamente. La principal dificultad de dichas herramientas es la especificación de las diferentes reglas de consistencia, que deben tenerse en cuenta cuando se usa una notación. En este artículo se presenta la especificación de dos reglas de consistencia del diagrama de clases de UML en el metaCASE DOME, codificadas en el lenguaje de programación Alter. Adicionalmente, se hace un análisis comparativo entre las especificaciones de los aspectos estructurales y de las reglas de consistencia en DOME y en la especificación de UML provista por el OMG.

  10. Remote Control of the CFHT Dome Shutter

    Science.gov (United States)

    Look, Ivan; Roberts, Larry; Vermeulen, Tom; Taroma, Ralph; Matsushige, Grant

    2011-03-01

    Several years ago CFHT proposed developing a Remote Observing Environment aimed at producing Science Observations at their Facility on Mauna Kea from their Headquarters in Waimea, HI. This Remote Observing Project commonly referred to as OAP (Observatory Automation Project) was completed at the end of January 2011 and has been providing the majority of Science Data since. My poster will attempt to provide Design Information on the Dome Shutter, which is both Controlled and Monitored Remotely from Waimea. The Dome Shutter Control System incorporates an upgraded Allen-Bradley PLC processor (SLC 5/05), which provides Remote Operation and Monitoring of the existing System. Several earlier upgrade projects were integrated to provide improvement to the Shutter System such as PLC Control, System Feedback, and Safety Features. This particular upgrade provides Remote capability, CFHT developed Control GUI, and Remote monitoring that promise to deliver a more versatile, visual, and safer Shutter Operation. The Dome Shutter Control System provides three modes of Operation namely; Remote, Integration, and Local. The Control GUI is used to operate the Shutter remotely. Integration mode is provided to develop PLC software code and is performed by connecting a Laptop directly to the Shutter Control Panel. Local mode is retained to provide Remote Lockout (No Remote Control), which allows Shutter control ONLY via the existing Electrical Panel. This mode is primarily intended for Shutter maintenance and troubleshooting. The Dome Shutter remains the first Line-of-Defense for Telescope protection due to inclement weather and so special attention was considered during Remote development. The Shutter has been equipped with an Autonomous Shutdown sequence in the event of Power or Network failure. If Loss of HELCO Power or Start-up of our Stand-by Diesel Generator is detected; a planned timing sequence will Close the Shutter Automatically. Likewise, an internal CFHT Network heartbeat was

  11. MROI Array telescopes: the relocatable enclosure domes

    Science.gov (United States)

    Marchiori, G.; Busatta, A.; Payne, I.

    2016-07-01

    The MROI - Magdalena Ridge Interferometer is a project which comprises an array of up to 10 1.4m diameter mirror telescopes arranged in a "Y" configuration. Each of these telescopes will be housed inside a Unit Telescope Enclosure (UTE) which are relocatable onto any of 28 stations. EIE GROUP Srl, Venice - Italy, was awarded the contract for the design, the construction and the erection on site of the MROI by the New Mexico Institute of Mining and Technology. The close-pack array of the MROI - including all 10 telescopes, several of which are at a relative distance of less than 8m center to center from each other - necessitated an original design for the Unit Telescope Enclosure (UTE). This innovative design enclosure incorporates a unique dome/observing aperture system to be able to operate in the harsh environmental conditions encountered at an altitude of 10,460ft (3,188m). The main characteristics of this Relocatable Enclosure Dome are: a Light insulated Steel Structure with a dome made of composites materials (e.g. glass/carbon fibers, sandwich panels etc.), an aperture motorized system for observation, a series of louvers for ventilation, a series of electrical and plants installations and relevant auxiliary equipment. The first Enclosure Dome is now under construction and the completion of the mounting on site id envisaged by the end of 2016. The relocation system utilizes a modified reachstacker (a transporter used to handle freight containers) capable of maneuvering between and around the enclosures, capable of lifting the combined weight of the enclosure with the telescope (30tons), with minimal impacts due to vibrations.

  12. Tephra layers in the Siple Dome and Taylor Dome ice cores, Antarctica: Sources and correlations

    Science.gov (United States)

    Dunbar, Nelia W.; Zielinski, Gregory A.; Voisins, Daniel T.

    2003-08-01

    Volcanic ash, or tephra layers, are found in the Taylor Dome, Siple Dome A, and Siple Dome B ice cores. Significant shard concentrations are found at a number of depths in all three cores. Electron and ion microprobe analyses indicate that the geochemical composition of most layers is basaltic, basanitic, or trachytic, and the geochemical signatures of the layers suggest derivation from the Pleiades volcanic center, Mt. Melbourne volcano, or small mafic centers, probably in the Royal Society Range area. Presence of tephra layers suggests an episode of previously unrecognized Antarctic volcanic activity between 1776 and 1805 A.D., from at least two volcanic centers. A strong geochemical correlation (D = 3.49 and 3.97 with a value of 4 considered identical) is observed between tephra layers at depth of 79.2 m in the Taylor Dome ice core, and layers between 97.2 and 97.7 m depth in the Siple B core. This correlation, and the highly accurate depth-age scale of the Siple B core suggest that the age of this horizon in the Taylor Dome ice core presented by [1998a, 2000] should be revised downward, to the younger age of 675 ± 25 years before 1995. This revised chronology is consistent with vertical strain measurements presented by [2003].

  13. Hemispherical optical dome for underwater communication

    Science.gov (United States)

    Shiri, Ron S.; Lunde, Emily L.; Coronado, Patrick L.; Quijada, Manuel A.

    2017-08-01

    For many years, acoustic systems have been used as the primary method for underwater communication; however, the data transfer rate of such systems is low because sound propagates slowly through water. A higher throughput can be achieved using visible light to transmit data underwater. The first issue with this approach is that there is generally a large loss of the light signal due to scattering and absorption in water, even though there is an optimal wavelength for transmission in the blue or green wavelengths of the visible spectrum. The second issue is that a simple communication system, consisting only of a highly directional source/transmitter and small optical detector/receiver, has a very narrow field of view. The goal of this project is to improve an optical, underwater communication system by increasing the effective field of view of the receiving optics. To this end, we make two changes to the simple system: (1) An optical dome was added near the receiver. An array of lenses is placed radially on the surface of the dome, reminiscent of the compound eye of an insect. The lenses make the source and detector planes conjugate, and each lens adds a new region of the source plane to the instrument's total field of view. (2) The receiver was expanded to include multiple photodiodes. With these two changes, the receiver has much more tolerance to misalignments (in position and angle) of the transmitter. Two versions of the optical dome (with 6" and 8" diameters) were designed using PTC's Creo CAD software and modeled using Synopsys' CODE V optical design software. A series of these transparent hemispherical domes, with both design diameters, were manufactured using a 5-axis mill. The prototype was then retrofitted with lenses and compared with the computer-generated model to demonstrate the effectiveness of this solution. This work shows that the dome design improves the optical field of view of the underwater communication system considerably. Furthermore, with

  14. Hemispherical Optical Dome for Underwater Communication

    Science.gov (United States)

    Shiri, Ron S.; Lunde, Emily L.; Coronado, Patrick L.; Quijada, Manuel A.

    2017-01-01

    For many years, acoustic systems have been used as the primary method for underwater communication; however, the data transfer rate of such systems is low because sound propagates slowly through the water. A higher throughput can be achieved using visible light to transmit data underwater. The first issue with using this approach is that there is generally a large loss of the light signal due to scattering and absorption in water even though there is an optimal wavelength for transmission in the blue or green wavelengths of the visible spectrum. The second issue is that a simple system consisting only of a highly directional source transmitter and small optical detector receiver has a very narrow field of view. The goal of this project is to improve an optical, underwater communication system by increasing the effective field of view of the receiving optics. To this end, we make two changes to the simple system: (1) An optical dome was added near the receiver. An array of lenses is placed radially on the surface of the dome, reminiscent of the compound eye of an insect. The lenses make the source and detector planes conjugate, and each lens adds a new region of the source plane to the instrument's total field of view. (2) The receiver was expanded to include multiple photodiodes. With these two changes, the receiver has much more tolerance to misalignments (in position and angle) of the transmitter.Two versions of the optical dome (with 6 and 8 diameters) were designed using the CREO CAD software and modeled using the CODE V optical design software. A series of these transparent hemispherical domes, with both design diameters, were manufactured using a 5-axis mill. The prototype was then retrofitted with lenses and compared with the computer-generated model to demonstrate the effectiveness of this solution. This work shows the dome design improves the optical field of view of the underwater communication system considerably. Furthermore, with the experimental test

  15. Conformal dome aberration correction by designing the inner surface

    Science.gov (United States)

    Zhang, Wang; Chen, Shouqian; Fan, Zhigang

    2016-12-01

    The ray transmission models of optical domes were established, and the characteristics of the rays while passing through a hemispherical dome and a conformal dome were comparatively analysed. Acquiring the minimum deviated angles from the inner surface of the conformal dome was then determined to be the designing goal for reducing the dynamic aberrations. Based on this, the inner surface of the conformal dome was optimized and thus, the dynamic aberrations were reduced. Finally, a completely cooled conformal optical system was designed. The results show that the optical system have produced good imaging quality within all the fields of regard, which further illustrates that designing the inner surface of a conformal dome is an effective method for aberration correction.

  16. SOLUTION MINING IN SALT DOMES OF THE GULF COAST EMBAYMENT

    Energy Technology Data Exchange (ETDEWEB)

    Griswold, G. B.

    1981-02-01

    Following a description of salt resources in the salt domes of the gulf coast embayment, mining, particularly solution mining, is described. A scenario is constructed which could lead to release of radioactive waste stored in a salt dome via inadvertent solution mining and the consequences of this scenario are analyzed.

  17. Superconducting Dome in a Gate-Tuned Band Insulator

    NARCIS (Netherlands)

    Ye, J. T.; Zhang, Y. J.; Akashi, R.; Bahramy, M. S.; Arita, R.; Iwasa, Y.

    2012-01-01

    A dome-shaped superconducting region appears in the phase diagrams of many unconventional superconductors. In doped band insulators, however, reaching optimal superconductivity by the fine-tuning of carriers has seldom been seen. We report the observation of a superconducting dome in the

  18. Morphodynamics of dome dunes under unimodal wind regimes

    Science.gov (United States)

    Gao, Xin; Narteau, Clement; Rozier, Olivier

    2017-04-01

    Dome dunes are isolated sand piles with a rounded shape and no slip face. They are not only incipient or disappearing dunes, they can also reach a giant size and form dome-dune fields. Nevertheless, unlike other types of dunes, they have not been the subject of intense research, certainly because they result from complex multidirectional wind regimes. Here we analyze the morphodynamics of dome dunes under unimodal wind regimes. From numerical modeling using a normal distribution of sand flux orientation, we show that the transition from barchan to dome dunes occur when the standard deviation is larger than 40°. As confirmed by sand flux roses of dome-dune fields in arid deserts on Earth, it corresponds to RDP/DP-value of 0.8 (RDP/DP is the ratio between the resultant drift potential and the drift potential). Both in the field and in the numerical model, the transition from barchan to dome-dunes can also be captured from the coefficient of variation of the planar dune shape. Not surprisingly, smaller dome dunes are faster than larger ones. However, the dependence of dune migration rate on the RDP-value changes according to the presence or absence of slip faces because of the speed-up effect. Transient finger dunes may develop in dome-dune fields, but they rapidly break-up into smaller bodies. This shows that, contrary to bidirectional wind regimes, a large dispersion of sand flux orientation is not efficient in building longitudinal dunes.

  19. Transdomes: Emplacement of Migmatite Domes in Oblique Tectonic Settings

    Science.gov (United States)

    Teyssier, C. P.; Rey, P. F.; Whitney, D. L.; Mondy, L. S.; Roger, F.

    2014-12-01

    Many migmatite domes are emplaced within wrench corridors in which a combination of strike-slip and extensional detachment zones (pull-apart, extensional relay, or transfer zones) focus deep-crust exhumation. The Montagne Noire dome (France, Variscan Massif Central) exemplifies wrench-related dome formation and displays the following structural, metamorphic, and geochronologic characteristics of a 'transdome': the dome is elongate in the direction of extension; foliation outlines a double dome separated by a high-strain zone; lineation is shallowly plunging with a fairly uniform trend that parallels the strike of the high-strain zone; subdomes contain recumbent structures overprinted by upright folds that affected upward by flat shear zones associated with detachment tectonics; domes display a large syn-deformation metamorphic gradient from core (upper amphibolite facies migmatite) to margin (down to greenschist facies mylonite); some rocks in the dome core experienced isothermal decompression revealed by disequilibrium reaction textures, particularly in mafic rocks (including eclogite); and results of U-Pb geochrononology indicate a narrow range of metamorphic crystallization from core to mantling schist spanning ~10 Myr. 3D numerical modeling of transdomes show that the dome solicits a larger source region of partially molten lower crust compared to 2D models; this flowing crust creates a double-dome architecture as in 2D models but there are differences in the predicted thermal history and flow paths. In a transtension setting, flow lines converge at depth (radial-centripetal flow) toward the zone of extension and diverge at shallow levels in a more uniform direction that is imposed by upper crust motion and deformation. This evolution produces a characteristic pattern of strain history, progressive fabric overprint, and P-T paths that are comparable to observed dome rocks.

  20. 1-D-ice flow modelling at EPICA Dome C and Dome Fuji, East Antarctica

    Directory of Open Access Journals (Sweden)

    F. Parrenin

    2007-06-01

    Full Text Available One-dimensional (1-D ice flow models are used to construct the age scales at the Dome C and Dome Fuji drilling sites (East Antarctica. The poorly constrained glaciological parameters at each site are recovered by fitting independent age markers identified within each core. We reconstruct past accumulation rates, that are larger than those modelled using the classical vapour saturation pressure relationship during glacial periods by up to a factor 1.5. During the Early Holocene, changes in reconstructed accumulation are not linearly related to changes in ice isotopic composition. A simple model of past elevation changes is developed and shows an amplitude variation of 110–120 m at both sites. We suggest that there is basal melting at Dome C (0.56±0.19 mm/yr. The reconstructed velocity profile is highly non-linear at both sites, which suggests complex ice flow effects. This induces a non-linear thinning function in both drilling sites, which is also characterized by bumps corresponding to variations in ice thickness with time.

  1. PENGEMBANGAN DESA WISATA RUMAH DOME BERBASIS AGROINDUSTRI PANGAN LOKAL (Kajian Diversifikasi Ketela Pohon di Desa Wisata Rumah Dome Prambanan

    Directory of Open Access Journals (Sweden)

    Susi Wuri Ani

    2013-11-01

    Full Text Available Pangan merupakan kebutuhan utama dalam kehidupan manusia. Pemenuhan kebutuhan pangan baik dari segi jumlah, mutu, gizi maupun keamanan berkaitan dengan Sumberdaya Manusia (SDM. Kualitas konsumsi pangan dan gizi masyarakat menentukan SDM masyarakat tersebut. Agroindustri pangan lokal merupakan kegiatan yang memberdayakan sumberdaya lokal (indigenous resources. Seluruh potensi lokal dimanfaatkan untuk menguatkan agroindustri pangan lokal. Penduduk di kawasan wisata Rumah Dome belum mampu mengolah bahan pangan lokal. Kegiatan ini bertujuan membentuk kelompok usaha produktif Ibu-Ibu PKK di Rumah Dome untuk dapat meningkatkan nilai ekonomis pangan lokal (ketela pohon. Hal yang dilakukan adalah memberikan pelatihan pengolahan ketela pohon menjadi ceriping singkong berbagai rasa, keripik belut daun singkong, membuat brownies berbahan tepung ketela, mengemas produk dengan brand Rumah Dome dan memberikan pelatihan pembukuan sederhana. Dengan kegiatan ini diharapkan akan tumbuh kelompok usaha produktif sehingga dapat mengangkat citra wisata Rumah Dome dan meningkatkan pendapatan masyarakat di Rumah Dome. Abstract Food is a major necessity in human life. Food needs are important for human resource (HR both in terms of quantity and quality. Quality of food consumption and nutrition communities determine the HR community. Local food agroindustry is an activity that empowers local resources (indigenous resources. The whole potential of local food used to strengthen local agroindustry. Residents in the tourist area of Dome House have not been able to process local food. This activity aims to establish productive business of woman group (PKK in Dome House to increase the economic value of local food (cassava. The activities are training for production process, packaging with Dome House’s brand and simple accounting management. The cassava processing training are: (1 making variety flavors of cassava chips; (2 producing eel chips from cassava leaves and (3

  2. Polygenetic Nature of a Rhyolitic Dome: Cerro Pizarro, Eastern Mexico

    Science.gov (United States)

    Carrasco-Nuñez, G.; Riggs, N.

    2006-12-01

    Rhyolitic domes are commonly regarded as monogenetic volcanoes associated with single, brief eruptions, such as those forming basaltic scoria cones; this contrasts with domes of andesitic or dacitic composition that usually show a complex evolution. Rhyolitic domes are characterized by short-lived successions of pyroclastic and effusive activity associated with a series of discrete eruptive events that commonly last on the order of years to decades or perhaps centuries. Cerro Pizarro is an isolated rhyolitic dome with a volume of ~1.1 km3, located in the eastern Mexican Volcanic Belt, in the intermontane Serdán-Oriental basin. Cerro Pizarro has an eruptive history similar to a polygenetic volcano, including a complex evolution of alternating explosive and effusive eruptions, a cryptodome phase, and sector collapse, marked chemical variations with time, and long-term repose periods (~ 50-80 ky) between eruptions that reveals intermittent injection of magmas. Whereas major element chemistry does not show significant changes, trace and rare-earth elements show marked differences between the last eruptive episode and the initial and intermediate stages of activity. Other rhyolitic domes such as Glass Mountain, CA, Taylor Creek, NM, South Sister domes, OR, and the Mono Inyo complex, CA, show moderate to strong chemical variations. These domes, however, are related to larger volcanic fields or are dome complexes formed by numerous vents, in contrast with Cerro Pizarro, which is an isolated volcano with no apparent relation to nearby larger volcanic systems (e.g., Los Humeros caldera). This eruptive behavior provides new insights into how rhyolite domes may evolve. A protracted, complex evolution bears important implications for hazard assessment. Activity at Cerro Pizarro leads us to speculate that isolated rhyolitic systems may become reactivated, potentially after tens of thousands of years.

  3. The Effects of the Foldable Dome of KDUST on the Observation Based on CFD Method at Dome A

    Science.gov (United States)

    Xu, Jianghai; Gong, Xuefei; Gu, Bozhong

    2016-12-01

    For modern telescopes with the strict requirement of high-resolution image quality, the influence of wind load cannot be ignored. KDUST is a 2.5 m optical telescope and will be installed at Dome A. To study the effects of wind load on KDUST, the low-frequency wind speed data observed by KL-AWS-2G weather station at Dome A are transformed into high frequency based on the theory of wind speed fluctuation spectrum; then, the numerical wind tunnel simulation is conducted under the conditions of different dominant wind directions, different dome opening angles, and the elevation angles of KDUST. The results show that different wind directions mainly affect the wind velocity and turbulence kinetic energy around the telescope; the optical path difference increases along with the increase of the dome opening angle, but decreases with the increase of the elevation angle of KDUST; the dome seeing decreases with the increase of both the dome opening angle and elevation angle. This simulation will provide a useful reference for the future design and construction of KDUST and its foldable dome.

  4. Building Guastavino dome in China: A historical survey of the dome of the Auditorium at Tsinghua University

    Directory of Open Access Journals (Sweden)

    Yishi Liu

    2014-06-01

    The first part combs up the intellectual origins and precedents of the campus planning by Henry Murphy. As the dome is a focal point of the study, a brief course on the history of dome construction in the West is needed. The third part, based upon field measurement in July 2013, compares the actual dome with its original design featured by the Guastavino method, deducing possible reasons that resulted in the differences, including architect׳s unfamiliarity with Guastavino Company and its parameters, considerations about cost, and local construction tradition.

  5. Calculation of pressure- and migration-constrained dynamic CO2 storage capacity of the North Sea Forties and Nelson dome structures

    OpenAIRE

    Babaei, Masoud; Govindan, Rajesh; Korre, Anna; Shi, Ji-Quan; Durucan, Sevket; Quinn, Martyn

    2016-01-01

    This paper presents a numerical simulation study of CO2 injection into the Forties and Nelson dome structures in the North Sea. The study assumes that these structures are fully depleted of their remaining hydrocarbon and brine has replaced their pore space, and therefore the structures can be treated as saline aquifers. Under this assumption, the objective is to calculate the dynamic CO2 storage capacity of the Forties and Nelson structures and design an injection scenario to enhance storage...

  6. Corrosion investigation of material combinations in a mobile phone dome-key pad system

    DEFF Research Database (Denmark)

    Ambat, Rajan; Møller, Per

    2007-01-01

    Mobile phone dome-key pad system is the device that connects the phone keys to the printed circuit board (PCB). The material combination for a typical dome-key pad system is Ag/AISI 202 steel for the dome and Au/Ni/Cu for the key pad. Under humid conditions dome-key pad system is susceptible...

  7. The E-ELT Project: the Dome design status

    Science.gov (United States)

    Marchiori, G.; de Lorenzi, S.; Busatta, A.

    2010-07-01

    Status of the Feasibility Study of E-ELT, the ESO 42 m Extreme Large Telescope, with emphasis on the Dome architecture and erection. The Dome is a hemispherical shape concept servomechanism 86 m high, with an external diameter of 108 m and a 45 m wide Observing Slit. Such dimensions require the application of big structure technologies (like stadium, hangar etc), in order to comply with manufacturing, transport and assembly constrains. The mentioned technology must be fitted with mechanical and control system constrains required by this kind of servo-system. Mechanisms inside the Dome must be sufficiently light and stiff, and composite materials meet the above mentioned requirements. The management of the whole mass is extremely important for the services and power consumption. This paper describes how the above mentioned problems were handled during the E-ELT Dome Feed study.

  8. Astronaut Gerald Carr floats in forward dome area

    Science.gov (United States)

    1974-01-01

    Astronaut Gerald P. Carr, commander for the Skylab 4 mission, demonstrates the effects of zero-gravity as he floats in the forward dome area of the Orbital Workshop of the Skylab space station while in Earth orbit.

  9. Geometry of shoot apical dome and distribution of growth rates

    Directory of Open Access Journals (Sweden)

    Jerzy Nakielski

    2014-01-01

    Full Text Available The distribution of the relative elementary rate of growth (RERG in apical domes of various shapes and patterns of displacement lines can be analytically examined. The geometry of these domes may be described by parabolas of n-th order, the variant of the distribution of linear growth rate should be established along any displacement line (e.g. along the axis and then the RERG can be studied as the function depending on the position coordinates and the parameter n. Such investigations of several aplical domes of various shapes have been performed. The results confirm the occurrence of the minimum of relative, elementary growth rate (in volume in the subapical region of the dome independently of the type of geometry (n parabola order.

  10. Thoracic problems associated with hydatid cyst of the dome of the liver.

    Science.gov (United States)

    Yacoubian, H D

    1976-05-01

    Twenty patients with hydatid cyst of the dome of the liver are presented. In ten there were significant associated intrathoracic complications including pleural effusion, pleural empyema, erosion through the diaphragm into lung, various degrees of pneumonitis or pulmonary abscess, or severe destruction of both diaphragm and right lower pulmonary lobe. Bronchobiliary fistula was demonstrated at operation in five patients. Four patients had obstructive jaundice due to intrabiliary rupture of a liver hydatid. In 19 patients the cysts in the right lobe of the liver were evacuated through a right thoracotomy and incision of the diaphragm. In four of these, additional pulmonary resection was carried out. In one patient with left pleural empyema, tube drainage followed by rib resection was instituted. Two patients had common duct drainage for relief of obstructive jaundice. In 13 patients the ectocyst cavity was drained; in seven it was filled with saline and closed. One patient required evacuation and open packing of the right upper quadrant and lower right hemithorax. Thoracotomy is mandatory in patients with hydatid cyst of the dome of the liver for easier approach to the cyst and for management of coexisting intrathoracic complications.

  11. Aquarius Brightness Temperature Variations at Dome C and Snow Metamorphism at the Surface. [29

    Science.gov (United States)

    Brucker, Ludovic; Dinnat, Emmanuel Phillippe; Picard, Ghislain; Champollion, Nicolas

    2014-01-01

    The Antarctic Plateau is a promising site to monitor microwave radiometers' drift, and to inter-calibrate microwave radiometers, especially 1.4 GHz (L-band) radiometers on board the Soil Moisture and Ocean Salinity (SMOS), and AquariusSAC-D missions. The Plateau is a thick ice cover, thermally stable in depth, with large dimensions, and relatively low heterogeneities. In addition, its high latitude location in the Southern Hemisphere enables frequent observations by polar-orbiting satellites, and no contaminations by radio frequency interference. At Dome C (75S, 123E), on the Antarctic Plateau, the substantial amount of in-situ snow measurements available allows us to interpret variations in space-borne microwave brightness temperature (TB) (e.g. Macelloni et al., 2007, 2013, Brucker et al., 2011, Champollion et al., 2013). However, to analyze the observations from the Aquarius radiometers, whose sensitivity is 0.15 K, the stability of the snow layers near the surface that are most susceptible to rapidly change needs to be precisely assessed. This study focuses on the spatial and temporal variations of the Aquarius TB over the Antarctic Plateau, and at Dome C in particular, to highlight the impact of snow surface metamorphism on the TB observations at L-band.

  12. Practically Saline

    Directory of Open Access Journals (Sweden)

    Jonathan Schroeder MD

    2015-11-01

    Full Text Available Introduction. In December 2014, the Food and Drug Administration issued a recall of all Wallcur simulation products due to reports of their use in clinical practice. We present a case of septic shock and multiorgan failure after the accidental intravenous infusion of a nonsterile Wallcur simulation product. Case. The patient presented with symptoms of rigors and dyspnea occurring immediately after infusion of Wallcur Practi-0.9% saline. Initial laboratory evidence was consistent with severe septic shock and multiorgan dysfunction. His initial lactic acid level was 9 mmol/L (reference range = 0.5-2.2, and he had evidence of acute kidney injury and markers of disseminated intravascular coagulation. All 4 blood culture bottles isolated multidrug-resistant Empedobacter brevis. The patient recovered from his illness and was discharged with ciprofloxacin therapy per susceptibilities. Discussion. This patient represents the first described case of severe septic shock associated with the infusion of a Wallcur simulation product. Intravenous inoculation of a nonsterile fluid is rare and exposes the patient to unusual environmental organisms, toxins, or unsafe fluid characteristics such as tonicity. During course of treatment, we identified the possible culprit to be a multidrug-resistant isolate of Empedobacter brevis. We also discuss the systemic failures that led to this outbreak.

  13. Observer Kalman Filter Identification of Suspen-Dome

    Directory of Open Access Journals (Sweden)

    Guojun Sun

    2017-01-01

    Full Text Available A number of Suspen-Dome structures have been built, but there is some difficulty in using experimental data to obtain good modal parameters, especially modal damping. In this paper, an ANSYS numerical simulation of the 35.4 m span Suspen-Dome is presented. Firstly, the natural vibration characteristics of Suspen-Dome and dynamic response under some random forces were obtained. Then the results of the numerical simulation established that 60 modes are sufficient for a reasonable dynamic model. This model is used to represent the Suspen-Dome dynamic behavior, and OKID is then used to try to identify a model from simulated data. A 400-order model generated from OKID is shown to contain the 60 modes from ANSYS and is shown to give good predictions of the dynamic behavior of Suspen-Dome. The results of this paper can confirm that it can be a very efficient tool for the identification of models of Suspen-Dome dynamics.

  14. Air conditioning system for dome type baseball ground. Dome shiki yakyujo no kuki chowa

    Energy Technology Data Exchange (ETDEWEB)

    Takai, H.; Iwata, E.; Ogawa, H.; Takahashi, N.; Igawa, N.; Hanzawa, H.; Higuchi, Y. (Takenaka Corp., Tokyo (Japan))

    1994-04-05

    This paper describes characteristics in facility design for the Fukuoka Baseball Dome completed in 1993, and the related air conditioning plan, optical environment plan, and acoustic environment plan. This dome construction is characterized by its truss-type steel structure having a swing type openable roof. Opening the roof allows the building to accept natural environment, and closing it turns the building to an environment requiring artificial control. The optical environment plan has performed a sensory evaluation test on how a ball can be identified when it is pitched in different seasons and times using simulations that use computer graphics, and a model with a scale of one to fifty. The illumination system has adopted high-color rendering metal halide lamps. The acoustic environment plan has conducted a sound adsorbing construction over the whole roof area, and provided an air layer in the upper part thereof. As a result, the world's shortest reverberation time of 5.75 seconds at 500 Hz has been realized. In the thermal environment plan, a contrivance has been given on an energy saving air conditioning system that is formed by the usual room cooling method and a cool air circulation added with a circulating air flow sensible to audiences. 5 refs., 21 figs., 2 tabs.

  15. Regional geohydrology of the northern Louisiana salt-dome basin; Part I, conceptual model and data needs

    Science.gov (United States)

    Ryals, G.N.

    1982-01-01

    As part of the National Waste Terminal Storage Program, the U.S. Geological Survey is conducting a regional study of the geohydrology of the northern Louisiana salt-dome basin and developing a regional multi-layered ground-water flow model to determine regional flow paths. In the salt-dome basin the Tokio Formation and Brownstown Marl (Austin aquifer in this report), and Nacatoch Sand of Late Cretaceous age and the Wilcox Group, Carrizo Sand, Sparta Sand, and Cockfield Formation of Tertiary age contain regional aquifers within the maximum potential repository depth of 3,000 feet. The Cretaceous units contain saltwater throughout the basin. The Tertiary units contain freshwater to varying distances downdip from outcrop areas in the basin. Natural flow directions and rates of movement of groundwater have been changed in the salt-dome basin by the withdrawl of freshwater and by the injection of wastes (principally oil-field brines) into saline aquifers. Except for the Sparta aquifer, ground-water flow directions are not well known because of a lack of potentiometric data. A regional test-drilling program, to collect the data needed to document concepts of the flow system and to quantify inputs to the planned ground-water flow model, has been proposed. The Sparta aquifer is being modeled because data are available for the unit. As regional test drilling provides data on other units, will be added to the model developed for the Sparta aquifer. (USGS)

  16. Dome-shaped macula in eyes with myopic posterior staphyloma.

    Science.gov (United States)

    Gaucher, David; Erginay, Ali; Lecleire-Collet, Amelie; Haouchine, Belkacem; Puech, Michel; Cohen, Salomon-Yves; Massin, Pascale; Gaudric, Alain

    2008-05-01

    To describe an unusual feature in myopic eyes responsible for visual loss, which we call a dome-shaped macula. Retrospective, observational case series. After observing isolated cases of dome-shaped macula, we analyzed optical coherence tomography (OCT) scans of 140 highly myopic eyes present in our OCT database to find similar cases. Fifteen eyes of 10 patients had a dome-shaped macula. These patients all had undergone fluorescein angiography (FA), indocyanine green angiography (ICGA), and B-scan ultrasonography examinations. The mean refractive error of the affected eyes was -8.25 diopters (D; range, -2 to -15 D). Median visual acuity was 20/50. Recent visual impairment was noted in 11 of the 15 eyes studied, and metamorphopsia was noted in eight eyes. Four eyes were asymptomatic. FA showed atrophic changes in the macular retinal pigment epithelium (RPE) in all eyes, combined with focal points of leakage in seven of the 15 eyes. The dome-shaped appearance of the macula was visible on both B-scan ultrasonography and OCT: a characteristic bulge of the macular retina, RPE, and choroid within the concavity of the moderate posterior staphyloma was present in all eyes. In 10 eyes, OCT also showed a shallow foveal detachment at the top of the dome-shaped macula. A dome-shaped macula within a myopic staphyloma is an unreported type of myopic posterior staphyloma. The dome-shaped macula often is associated with RPE atrophic changes and foveal retinal detachment, which may explain the visual impairment in these eyes.

  17. Microbial characterization of microbial ecosystems associated to evaporites domes of gypsum in Salar de Llamara in Atacama desert.

    Science.gov (United States)

    Rasuk, Maria Cecilia; Kurth, Daniel; Flores, Maria Regina; Contreras, Manuel; Novoa, Fernando; Poire, Daniel; Farias, Maria Eugenia

    2014-10-01

    The Central Andes in northern Chile contains a large number of closed basins whose central depression is occupied by saline lakes and salt crusts (salars). One of these basins is Salar de Llamara (850 m a.s.l.), where large domed structures of seemingly evaporitic origin forming domes can be found. In this work, we performed a detailed microbial characterization of these domes. Mineralogical studies revealed gypsum (CaSO(4)) as a major component. Microbial communities associated to these structures were analysed by 454 16S rDNA amplicon sequencing and compared between winter and summer seasons. Bacteroidetes Proteobacteria and Planctomycetes remained as the main phylogenetic groups, an increased diversity was found in winter. Comparison of the upper air-exposed part and the lower water-submerged part of the domes in both seasons showed little variation in the upper zone, showing a predominance of Chromatiales (Gammaproteobacteria), Rhodospirillales (Alphaproteobacteria), and Sphingobacteriales (Bacteroidetes). However, the submerged part showed marked differences between seasons, being dominated by Proteobacteria (Alpha and Gamma) and Verrucomicrobia in summer, but with more diverse phyla found in winter. Even though not abundant by sequence, Cyanobacteria were visually identified by scanning electron microscopy (SEM), which also revealed the presence of diatoms. Photosynthetic pigments were detected by high-performance liquid chromatography, being more diverse on the upper photosynthetic layer. Finally, the system was compared with other endoevaporite, mats microbialite and Stromatolites microbial ecosystems, showing higher similitude with evaporitic ecosystems from Atacama and Guerrero Negro. This environment is of special interest for extremophile studies because microbial life develops associated to minerals in the driest desert all over the world. Nevertheless, it is endangered by mining activity associated to copper and lithium extraction; thus, its

  18. Characterization of the permutations by block that have reversible one dimensional cellular automata; Caracterizacion de las permutaciones en bloque que representan automatas celulares unidimensionales reversibles

    Energy Technology Data Exchange (ETDEWEB)

    Seck Tuoh Mora, J. C. [Instituto Politecnico Nacional, Mexico, D. F. (Mexico)

    2001-06-01

    We present a review of reversible one dimensional cellular automata and their representation by block permutations. We analyze in detail the behavior of such block permutations to get their characterization. [Spanish] En el siguiente escrito se da una revision a la representacion y comportamiento de automatas celulares unidimensionales reversibles por medio de permutaciones en bloque. Hacemos un analisis detallado del comportamiento de dichas permutaciones para obtener su caracterizacion.

  19. Explosive seismic reflection data from dome Halfarryggen, Antarctica

    Science.gov (United States)

    Hofstede, Coen

    2010-05-01

    Here we present the results from a explosive seismic survey performed in January 2010, at the ice dome Halfarryggen, close to the ice shelf Ekströmisen in East Antarctica. The dome lies 120 km south east of the German research station Neumayer. Two 6 km long perpendicular lines were shot over the dome, large enough to capture the structure of the present Raymond bump. For recording we used a 60 channel 1500 m long snow streamer. To reduce spatial aliasing two shots were combined into one data record. The focus of the seismic survey lies upon the physics that can be extracted from the internal and basal ice reflections. This includes bed conditions, crystal orientation fabric and seismic wave velocities.

  20. Analysis and test of low profile aluminum aerospace tank dome

    Science.gov (United States)

    Ahmed, R.; Wilhelm, J. M.

    1993-01-01

    In order to increase the structural performance of cryogenic tanks, the aerospace industry is beginning to employ low-profile bulkheads in new generation launch vehicle designs. This report details the analysis and test of one such dome made from 2219 aluminum. Such domes have two potential failure modes under internal pressure, general tensile failure and hoop compression buckling (in regions near the equator). The test determined the buckling load and ultimate tensile load of the hardware and showed that both compared well with the analysis predictions. This effort was conducted under the auspices of NASA and the General Dynamics Cryogenic Tank Technology Program (CTTP).

  1. Mud dome, stone dome and mud and stone dome in the rural buildings of vernacular architecture in center of Castilla y León (Spain

    Directory of Open Access Journals (Sweden)

    O. Abril Revuelta

    2017-06-01

    Full Text Available In the center of Castilla y León there are few examples of old rural buildings linked to economic activities that have developed in the agrarian field. These are known chozos and casetas, and they have been built with dome-shaped solutions using autochthon materials: mud and stone. The influence of traditional techniques of both elements has generated a singular typological rarely seen in the rest of the Iberian Peninsula. Different types of domes have been analyzed in situ. And they have been contrasted by documentary sources and it has significantly expanded the information published of them, especially about their typological variety and their construction process. This research aims to provide tools to restore a constructive knowledge that is forgotten in place, to value its architectural wealth, which can encourage their rehabilitation.

  2. Computed tomography-guided transpulmonary radiofrequency ablation for hepatocellular carcinoma located in hepatic dome

    National Research Council Canada - National Science Library

    Mitsuo Toyoda Satoru Kakizaki Katsuhiko Horiuchi Kenji Katakai Naondo Sohara Ken Sato Hitoshi Takagi Masatomo Mori Takahito Nakajima

    2006-01-01

    ...) for hepatocellular carcinoma (HCC) located in the hepatic dome. METHODS: A total of seven patients with HCC comprising seven nodules located in the hepatic dome were treated from April 2004 to December 2004...

  3. Single Stage Transthoracic Approach to the Right Lung and Liver Dome Hydatid Cysts

    Directory of Open Access Journals (Sweden)

    Rasih Yazkan

    2011-09-01

    lung, the hepatic lesions were all of the dome located. Conclusions :Single stage transthoracic approach is prevent the second surgical procedures on simultaneous right lung and liver dome hydatid cyst and it is safe and effective method.

  4. Dome-shaped macula: a compensatory mechanism in myopic anisometropia?

    Science.gov (United States)

    Keane, Pearse A; Mitra, Arijit; Khan, Imran J; Quhill, Fahd; Elsherbiny, Samer M

    2012-05-31

    The purpose of this article was to describe a patient with dome-shaped macula in the setting of mild myopic anisometropia and to speculate regarding the role of this feature as a compensatory mechanism in ocular development. The clinical records of a 49-year-old woman with this condition were reviewed. Spectral-domain optical coherence tomographic images revealed evidence of a dome-shaped macula. B-scan ultrasonography measured axial lengths of 23.8 mm in the right eye and 22.8 mm in the left eye. Spherical equivalents were -1.375 and +0.375 in the right and left eyes, respectively. Examination of the left eye was unremarkable. Dome-shaped macula has previously only been described in patients with high myopia. These findings support the hypothesis that myopic anisometropia, rather than absolute refractive status, is central to the development of dome-shaped macula and that this feature represents a protective mechanism aimed at reducing the effects of anisometropia. Copyright 2012, SLACK Incorporated.

  5. optimised intake stroke analysis for flat and dome head pistons

    African Journals Online (AJOL)

    user

    results were validate and comparisons developed to analyze the various optimization parameters for performance characteristics of the two pistons. Keywords: optimized intake stroke, CFD analysis, flat and dome head pistons, internal combustion engine, CAD modelling. NOMENCLATURE. = density. ⃑⃑ = uniform velocity.

  6. An application of LOTEM around salt dome near Houston, Texas

    Science.gov (United States)

    Paembonan, Andri Yadi; Arjwech, Rungroj; Davydycheva, Sofia; Smirnov, Maxim; Strack, Kurt M.

    2017-07-01

    A salt dome is an important large geologic structure for hydrocarbon exploration. It may seal a porous reservoir of rocks that form petroleum reservoirs. Several techniques such as seismic, gravity, and electromagnetic including magnetotelluric have successfully yielded salt dome interpretation. Seismic has difficulties seeing through the salt because the seismic energy gets trapped by the salt due to its high velocity. Gravity and electromagnetics are more ideal methods. Long Offset Transient Electromagnetic (LOTEM) and Focused Source Electromagnetic (FSEM) were tested over a salt dome near Houston, Texas. LOTEM data were recorded at several stations with varying offset, and the FSEM tests were also made at some receiver locations near a suspected salt overhang. The data were processed using KMS's processing software: First, for assurance, including calibration and header checking; then transmitter and receiver data are merged and microseismic data is separated; Finally, data analysis and processing follows. LOTEM processing leads to inversion or in the FSEM case 3D modeling. Various 3D models verify the sensitivity under the salt dome. In addition, the processing was conducted pre-stack, stack, and post-stack. After pre-stacking, the noise was reduced, but showed the ringing effect due to a low-pass filter. Stacking and post-stacking with applying recursive average could reduce the Gibbs effect and produce smooth data.

  7. Sustainable Outreach: Lessons Learned from Space Update and Discovery Dome

    Science.gov (United States)

    Reiff, P. H.; Sumners, C.; Law, C. C.

    2009-12-01

    A sustainable program lives on past its initial funding cycle, and develops a network of users that ensures continued life, either by fees, advertising revenue, or by making the program more successful in later sponsored grants. Teachers like free things, so having a sponsor for products such as lithographs or CD-Roms is key to wide distribution. In 1994 we developed “Space Update®”, under the NASA “Public Use of the Internet” program. It has new editions annually, with over 40,000 distributed so far (many purchased but most free at teacher and student workshops). In 1996 we created a special edition “Space Weather®”, which includes the space weather module from Space Update plus other resources. Initially developed with funding from the IMAGE mission, it is now sponsored by Cluster and MMS. A new edition is published annually and distributed in the “Sun-Earth Day” packet; total distribution now exceeds 180,000. “Earth Update” was created in 1999 under cooperative agreement “Museums Teaching Planet Earth”. It now has a total distribution of over 20,000. Both Earth Update and Space Update were developed to be museum kiosk software, and more than 15 museums have them on display. Over 4,000 users are active in our e-Teacher network and 577 in our museum educator network. Although these can certainly be considered successful because of their longevity and user base, we have had a far more dramatic sustainable program arise in the last six years… the “Discovery Dome®”. Invented at HMNS and developed under NASA Cooperative Agreement “Immersive Earth”, this dome was the first digital portable planetarium that also showed fulldome movies with an interactive interface (first shown to the public at the Dec 2003 AGU meeting). The Discovery Dome network (tinyurl.com/DiscDome) has spun those initial 6 NASA-funded domes into over 90 installations in 22 states and 23 countries. Creating high quality content is quite expensive and so needs

  8. Oxidation and compaction of a collapsed peat dome in Central Kalimantan

    NARCIS (Netherlands)

    Kool, D.M.; Buurman, P.; Hoekman, D.H.

    2006-01-01

    Peat domes in Kalimantan (Indonesia) are reported to loose their dome shape as a result of disturbance such as logging and artificial drainage. The loss of the dome shape can be caused by (a combination of) two major processes: compaction and oxidation. Because natural, undisturbed peat is a major

  9. Modeling of spatial variations of growth within apical domes by means of the growth tensor. II. Growth specified on dome surface

    Directory of Open Access Journals (Sweden)

    Zygmunt Hejnowicz

    2014-01-01

    Full Text Available Variations of the elemental relative rate of growth are modeled for parabolic, elliptic and hyperbolic domes of shoot apices by using the growth tensor in a suitable curvilinear coordinate system when the mode of area growth on the dome surface is known. Variations of growth rates within the domes are obtained in forms of computer-made maps for the following variants of growth on the dome surface: (1 constant meridional growth rate, (2 isotropic area growth, (3 anisotropy of area growth which becomes more intensive with increasing distance from the vertex. In variants 1 and 2 a maximum of volumetric growth rate appears in the center of the dome. Such a distribution of growth seems to be unrealistic. However, the corresponding growth tensors are interesting because they can be used in combination with other growth tensors to get the expected minimum volumetric growth rate in the dome center.

  10. Debris avalanches and slumps on the margins of volcanic domes on Venus: Characteristics of deposits

    Science.gov (United States)

    Bulmer, M. H.; Guest, J. E.; Beretan, K.; Michaels, Gregory A.; Saunders, R. Stephen

    1992-01-01

    Modified volcanic domes, referred to as collapsed margin domes, have diameters greater than those of terrestrial domes and were therefore thought to have no suitable terrestrial analogue. Comparison of the collapsed debris using the Magellan SAR images with volcanic debris avalanches on Earth has revealed morphological similarities. Some volcanic features identified on the seafloor from sonar images have diameters similar to those on Venus and also display scalloped margins, indicating modification by collapse. Examination of the SAR images of collapsed dome features reveals a number of distinct morphologies to the collapsed masses. Ten examples of collapsed margin domes displaying a range of differing morphologies and collapsed masses have been selected and examined.

  11. Sacral doming progression in developmental spondylolisthesis: a demonstrative case report with two different evolutions.

    Science.gov (United States)

    Gutman, Gabriel; Silvestre, Clément; Roussouly, Pierre

    2014-05-01

    Demonstrative case report of two different evolutions in developmental spondylolisthesis. To our knowledge spontaneous sacral doming reconstruction and healing has never been previously reported. Presentation of two cases with developmental spondylolisthesis and no sacral dome that had at the beginning a similar presentation and finally evolved in different ways. Initially, both cases were without sacral dome. In the first case, sacral dome appeared and completely healed in presence of a stable elongata pars and stable spondylolisthesis. In the second case, apparition, progression of sacral dome, rolling up of L5 and spondylolisthesis occurred in the presence of lytic defect in the pars. Sacral doming is secondary to L5 abnormal position regarding to S1. The mechanism of sacral doming looks like as an osteochondritis phenomena. Loss of support of the sacral plateau by sacral rounding may induce high grade spondylolisthesis.

  12. Geological evaluation of Gulf Coast salt domes: overall assessment of the Gulf Interior Region

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-10-01

    The three major phases in site characterization and selection are regional studies, area studies, and location studies. This report characterizes regional geologic aspects of the Gulf Coast salt dome basins. It includes general information from published sources on the regional geology; the tectonic, domal, and hydrologic stability; and a brief description the salt domes to be investigated. After a screening exercise, eight domes were chosen for further characterization: Keechi, Oakwood, and Palestine Domes in Texas; Vacherie and Rayburn's domes in North Louisiana; and Cypress Creek and Richton domes in Mississippi. A general description of each, maps of the location, property ownership, and surface geology, and a geologic cross section were presented for each dome.

  13. Treatment of subretinal fluid associated with dome-shaped macula.

    Science.gov (United States)

    Chinskey, Nicholas D; Johnson, Mark W

    2013-11-01

    Dome-shaped macula is a recently described disorder seen in eyes with myopic posterior staphyloma. Vision loss may accompany sub-macular fluid accumulation, for which no effective treatment has been reported. The authors report the successful treatment of two female patients, aged 34 and 59 years, with chronic exudative macular detachment associated with dome-shaped macula. Symptoms of subretinal fluid had been present for at least 2 years in each case, and the fluid was refractory to multiple intravitreal bevacizumab injections in one eye. After a single session of half-fluence verteporfin photodynamic therapy, the submacular fluid resolved completely in each eye. In one eye, recurrent submacular fluid 2 years later responded partially to repeat photodynamic therapy and completely to focal laser photocoagulation. [Ophthalmic Surg Lasers Imaging Retina. 2013;44:593-595.]. Copyright 2013, SLACK Incorporated.

  14. Dome-shaped macula associated with Best vitelliform macular dystrophy.

    Science.gov (United States)

    Battaglia Parodi, Maurizio; Zucchiatti, Ilaria; Fasce, Francesco; Cascavilla, Maria Lucia; Cicinelli, Maria Vittoria; Bandello, Francesco

    2015-01-01

    Dome-shaped macula (DSM) has been described recently as an inward convexity of the macula typical of myopic eyes detectable on spectral-domain optical coherence tomography (SD-OCT). The authors describe a case of monolateral DSM associated with Best vitelliform macular dystrophy (VMD). Case report. A 60-year-old man already diagnosed with VMD in vitelliruptive stage underwent SD-OCT that revealed the typical vitelliform material accumulation associated in the left eye with a convex elevation of the macula. No change was registered over a 1-year follow-up. This is the first report describing a monolateral DSM associated with VMD. Dome-shaped macula could be considered as a nonspecific scleral alteration, probably due to increased scleral thickness, which can accompany many retinal disorders.

  15. Visualisation and Immersion Dome Experience for Inspired Participation

    Directory of Open Access Journals (Sweden)

    Anna P. Gawlikowska

    2018-03-01

    Full Text Available Public protests, which lead to increased administrative and permission procedures, are amongst the most important obstacles in development of wind energy projects. The community’s fears of visual and acoustic impacts of new power plants are commonly recognized as the weakest aspects of public acceptance. To address these issues Visualisation Dome has been designed to better communicate the economic, political, spatial, ecological and social benefits of wind power plants and the associated risks to local communities. The approach combines the experimental and simulation method. The integrated analysis software tool, which allows assessing the impacts of planed wind power plants underpins their 360-degree video and audio simulations. The Visualisation Dome demonstration resulted in 57% of the interviewed participants improving their opinion of wind power following the experience. Visualisation Dome’s novel approach for improving procedural justice of wind energy projects development forms innovative, interactive and streamlined processes, and enables constructive participation of audiences.

  16. Arthroscopic intralesional curettage for large benign talar dome cysts

    Directory of Open Access Journals (Sweden)

    El Shazly Ossama

    2015-01-01

    Full Text Available Introduction: Surgical management of large talar dome cysts is challenging due to increased morbidity by associated cartilage damage and malleolar osteotomy. The purpose of this study is to evaluate the clinical and radiological outcome of endoscopic curettage and bone graft for large talar dome cysts. Methods: This is a retrospective analysis of data for eight patients (eight feet who were treated by arthroscopic curettage and grafting for large talar dome cysts. Seven cases were treated by posterior ankle arthroscopy as the lesion was located posteriorly while one case was treated by anterior ankle arthroscopy as the lesion was breached anteriorly. Results: The final diagnosis, was; large osteochondral lesion of talus (two cases, aneurysmal bone cyst (ABC (two case, intra-osseous ganglion (two cases, Chronic infection in talus (one case and angiomatous lesion of the talus (one case. The mean follow up period was 18.3 (±3.06 SD months (range 16–25 months. The median preoperative AOFAS score was 74.5 (±5.34 SD points. The mean postoperative AOFAS score at one year follow up was 94.6 (±2.97 SD points. None of the patient had recurrence of the lesion during follow up. Return to normal daily activity was achieved at 11.25 (±2.37 SD weeks. Discussion: In this short case series study, large talar dome bony cysts of different pathologies including aneurysmal bone cysts could be treated effectively by endoscopic curettage and bone grafting with no recurrence no complications during the follow-up period.

  17. The Second Deep Ice Coring Project at Dome Fuji, Antarctica

    Directory of Open Access Journals (Sweden)

    Hideaki Motoyama

    2007-09-01

    Full Text Available Throughout the history of the polar icecaps, dust and aerosols have been transported through the atmosphere to the poles, to be preserved within the annually freezing ice of the growing ice shields. Therefore, the Antarctic ice sheet is a “time capsule" for environmental data, containing information of ancient periods of Earth’s history. To unravel this history and decode cycles in glaciations and global change is among the major goals of the Dome Fuji Ice Coring Project.

  18. Solar Astrophysics, Interferometry, and Coronagraphy at DomeC/Concordia

    Science.gov (United States)

    Damé, L.; Amans, J.-P.; Dournaux, J.-L.; Koutchmy, S.; Lamy, P.; Preumont, A.

    Excellent seeing, coronal conditions, and very low IR thermal background are qualities of the Dome C/Concordia station site that will allow unique solar astrophysics science. We review the science case for inner corona observations (onset of the coronal heating mechanism still poorly understood) and the promises of high angular resolution to disentangle the possible mechanisms at work between waves, convection, and reconnection in this particularly magnetically structured solar atmosphere between the high chromosphere and inner corona. For coronagraphy, IR and high resolution possibilities, Dome C is a case by itself between classical ground-based sites and space opportunities. Telescopes from 50 cm (coronagraphy oriented) to 4 m (full high resolution advantage including IR access) are proposed to benefit from these remarkable observing capabilities. Using 3×O50 cm off-axis telescopes, we first propose a medium size facility (1.4 m equivalent telescope) for very high resolution access, ADSIIC (Antarctica Demonstrator of Solar Interferometric Imaging & Coronagraphy), before the ultimate 9-telescope Solar Facility equivalent to a 4 m diameter telescope: A-FOURMI (Antarctica 4 m Interferometer). Finally, 30 m tower designs and their logistics using standard containers and elementary elements of 6 m maximum length, are presented and discussed. These towers are indeed of general interest also for the other optical and IR telescopes intended for Dome C/Concordia, allowing to get over most of the turbulent ground layer and to reach the best possible permanent seeing conditions (better than half an arcsec).

  19. An Operationally Based Vision Assessment Simulator for Domes

    Science.gov (United States)

    Archdeacon, John; Gaska, James; Timoner, Samson

    2012-01-01

    The Operational Based Vision Assessment (OBVA) simulator was designed and built by NASA and the United States Air Force (USAF) to provide the Air Force School of Aerospace Medicine (USAFSAM) with a scientific testing laboratory to study human vision and testing standards in an operationally relevant environment. This paper describes the general design objectives and implementation characteristics of the simulator visual system being created to meet these requirements. A key design objective for the OBVA research simulator is to develop a real-time computer image generator (IG) and display subsystem that can display and update at 120 frame s per second (design target), or at a minimum, 60 frames per second, with minimal transport delay using commercial off-the-shelf (COTS) technology. There are three key parts of the OBVA simulator that are described in this paper: i) the real-time computer image generator, ii) the various COTS technology used to construct the simulator, and iii) the spherical dome display and real-time distortion correction subsystem. We describe the various issues, possible COTS solutions, and remaining problem areas identified by NASA and the USAF while designing and building the simulator for future vision research. We also describe the critically important relationship of the physical display components including distortion correction for the dome consistent with an objective of minimizing latency in the system. The performance of the automatic calibration system used in the dome is also described. Various recommendations for possible future implementations shall also be discussed.

  20. Percutaneous extrapulmonary radiofrequency ablation for tumors in the hepatic dome.

    Science.gov (United States)

    Wang, Zhen-Yuan; Sun, Wen-Bing; Li, Ming-Ying; Zhang, Xiao-Xia; Ding, Xue-Mei

    2008-01-01

    This study aims to assess the feasibility of one lung ventilation and computed tomography-guided extrapulmonary percutaneous radiofrequency ablation for tumors in the hepatic dome. Eleven patients (10 men, 1 women; age range, 34-84 years) with 12 tumors in the hepatic dome were enrolled in the study after institutional review board approval and informed consent had been obtained. A 35F or 37F left-sided double-lumen endotracheal tube was intubated after general anesthesia was induced. The right lung is permitted to collapse, with selective left lungs ventilation. With CT monitoring, the RF electrode was inserted through the empty pleural space to the targeted tumor and radiofrequency ablation procedures were performed. The median operative time was 122 minutes. The median one lung ventilation time was 134 minutes. The procedures of one lung ventilation and percutaneous radiofrequency ablation were successfully performed. There was no bronchial intubation, one lung ventilation and percutaneous radiofrequency ablation related complications, excluding minor pleural effusions recovering without thoracentesis in 2 patients. Complete tumor necrosis was achieved in 10 patients (90.9%). One lung ventilation and computed tomography guided percutaneous extrapulmonary radiofrequency ablation for tumors in the hepatic dome appears to be useful and safe.

  1. Ice crystal precipitation at Dome C site (East Antarctica)

    Science.gov (United States)

    Santachiara, G.; Belosi, F.; Prodi, F.

    2016-01-01

    For the first time, falling ice crystals were collected on glass slides covered with a thin layer of 2% formvar in chloroform at the Dome Concordia site (Dome C), Antarctica. Samplings were performed in the framework of the 27th Italian Antarctica expedition of the Italian National Program for Research in Antarctica in the period 21 February-6 August 2012. Events of clear-sky precipitations and precipitations from clouds were considered and the replicas obtained were examined under Scanning Electron Microscope (SEM). Several shapes of ice crystals were identified, including ;diamond dust; (plates, pyramids, hollow and solid columns), and crystal aggregates varying in complexity. Single events often contained both small (10 μm to 50 μm) and large (hundreds of microns) crystals, suggesting that crystals can form simultaneously near the ground (height of a few hundred metres) and at higher layers (height of thousands of metres). Images of sampled crystal replicas showed that single bullets are not produced separately, but by the disintegration of combinations of bullets. Rimed ice crystals were absent in the Dome C samples, i.e. the only mode of crystal growth was water vapour diffusion. On considering the aerosol in the sampled crystals, we reached the conclusion that inertial impaction, interception and Brownian motion were insufficient to explain the scavenged aerosol. We therefore presume that phoretic forces play a role in scavenging during the crystal growth process.

  2. Risk Assessment of Carbon Sequestration into A Naturally Fractured Reservoir at Kevin Dome, Montana

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Minh [Univ. of Wyoming, Laramie, WY (United States); Onishi, Tsubasa [Texas A & M Univ., College Station, TX (United States); Carey, James William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Will, Bob [Schlumberger, Houston, TX (United States); Zaluski, Wade [Schlumberger, Houston, TX (United States); Bowen, David [Montana State Univ., Bozeman, MT (United States); DeVault, Brian [Vecta Oil and Gas, Dallas, TX (United States); Duguid, Andrew [Battelle Memorial Inst., Columbus, OH (United States); Spangler, Lee [Montana State Univ., Bozeman, MT (United States); Stauffer, Philip H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-12-22

    In this report, we describe risk assessment work done using the National Risk Assessment Partnership (NRAP) applied to CO2 storage at Kevin Dome, Montana. Geologic CO2 sequestration in saline aquifers poses certain risks including CO2/brine leakage through wells or non-sealing faults into groundwater or to the land surface. These risks are difficult to quantify due to data availability and uncertainty. One solution is to explore the consequences of these limitations by running large numbers of numerical simulations on the primary CO2 injection reservoir, shallow reservoirs/aquifers, faults, and wells to assess leakage risks and uncertainties. However, a large number of full-physics simulations is usually too computationally expensive. The NRAP integrated assessment model (NRAP-IAM) uses reduced order models (ROMs) developed from full-physics simulations to address this issue. A powerful stochastic framework allows NRAPIAM to explore complex interactions among many uncertain variables and evaluate the likely performance of potential sequestration sites.

  3. Salinity and water quality

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    The impact of salinity on greenhouse grown crops, especially when grown in substrate systems, differs from the impact of salinity on crops grown under field conditions. The most striking difference between greenhouse and field conditions is the overall much higher concentrations of nutrients in

  4. Salinity in rose production

    Directory of Open Access Journals (Sweden)

    Michele Reis

    2016-09-01

    Full Text Available The rose is one of the most important ornamental plants in the world. However, the cultivation systems used for roses often impose salt stress. Saline conditions occur naturally in some regions or by human activity in others with use of low quality water or excessive fertilizer application. In general, roses are considered sensitive to salinity. However, tolerance levels can be different among roses species and cultivars. Therefore, studies are needed that take into account characteristics of each species and how the exposure to salinity occurs. Management of water and nutrients can be important tools for mitigating the effects of high salt concentrations. Also, advances in biotechnology can be used for a better understanding of the physiological responses to salinity and to develop more salt tolerant rose cultivars. Thus, this paper aims to review the progress made and future prospects of salinity tolerance in commercial rose production.

  5. Remote sensing of salinity

    Science.gov (United States)

    Thomann, G. C.

    1975-01-01

    The complex dielectric constant of sea water is a function of salinity at 21 cm wavelength, and sea water salinity can be determined by a measurement of emissivity at 21 cm along with a measurement of thermodynamic temperature. Three aircraft and one helicopter experiments using two different 21 cm radiometers were conducted under different salinity and temperature conditions. Single or multiple ground truth measurements were used to calibrate the data in each experiment. It is inferred from these experiments that accuracies of 1 to 2%/OO are possible with a single surface calibration point necessary only every two hours if the following conditions are met--water temperatures above 20 C, salinities above 10%/OO, and level plane flight. More frequent calibration, constraint of the aircraft's orientation to the same as it was during calibration, and two point calibration (at a high and low salinity level) rather than single point calibration may give even better accuracies in some instances.

  6. Characterization of the billow applied to Tuxpan, Veracruz; Caracterizacion del oleaje aplicada a Tuxpan, Veracruz

    Energy Technology Data Exchange (ETDEWEB)

    Rosales Sierra, Victor

    1999-07-01

    In this work, the criteria for the wave temporal and spectral statistical analysis were reviewed. These analysis are applied to the site Tuxpan, Veracruz, in the Mexican Gulf coast. In the temporal statistic analysis, the high (Rayleigh, Tayfun and Carter) and period (Bretchneider, Cavanie and Longuet-Higgins) theoretic probability distributions are compared with field data from Tuxpan. In the other hand, in the frequency domain analysis, the theoretic spectrums (Bretchneider-Mitsuyasu, Jonswap-Hasselmann, Pierson-Moscowitz, Neumann, ITTC, ISSC, TMA and Ochi-Hubble) are compared with the one obtained from Tuxpan measurements, then changes are made to some spectrums in order to better couple to field data. Finally, some recommendations are made to improve the wave data acquisition and analysis methods. From the study results, it's important to mention that the Tayfun high probability distribution and the Cavanie period probability distribution better fit Tuxpan field data. In the spectral analysis, the Bretchneider spectrum, modified by Mitsuyasu, better coupled to the spectrum obtained from Tuxpan field data. In the temporal statistical analysis, correct the mean level using the parabolic approximation, in order to eliminate the tidal and long period wave effects, it is recommended. For the registered individual wave calculus the zero up cross method was used. [Spanish] En este trabajo se revisan los criterios para el analisis estadisticos temporal y espectral del oleaje, mismos que son aplicados para la caracterizacion del oleaje en Tuxpan, Veracruz. En cuanto al analisis estadistico temporal, se comparan las distribuciones teoricas de probabilidad de altura de Rayleigh, Tayfun y Carter; y las de periodo de Bretchneider, Cavanie y Longuet-Higgins contra las resultantes de las mediciones en campo. Por otro lado y concerniente al analisis en el dominio de la frecuencia, se comparan los espectros teoricos de Bretchneider- Mitsuyasu, Jonswap-Hasselmann, Pierson

  7. The decorative program of the domes and area under the domes in the church of the monastery Resava

    Directory of Open Access Journals (Sweden)

    Prolović Jadranka

    2008-01-01

    Full Text Available Because the dome is interpreted as a symbol of the heavens, it is reserved for heavenly subjects. The calotte of the dome is seen as a vault of heaven or 'heaven in the heavens' and, as such, as the 'house of Christ'. As the commentator in the 19th century reports, the image of Christ Pantokrator was once located at the zenith of the central dome of Resava. The preserved scenes and figures below the dome, specifically the heavenly liturgy and the prophets, confirm the original existence of this image. Together they build an iconology that was very widespread in late Byzantine art. The composition of the central dome of Resava resembles in its complete appearance, supported by some particularities, the central dome of Ravanica, which served as a model for the artists of Resava. One can find close parallels for the decoration of the side domes in Ravanica. The similar arrangement of heavenly powers in the tambours of the domes in Ravanica and Resava indicate that, like in Ravanica, Christ Emmanuel, the Age of Days, the Mother of God and the Archangel Michael could have been depicted in the zenith of the side domes of Resava. This type of decorative scheme in side domes is common in late Byzantine monumental painting. The remaining fragments with images of angels as deacons positioned in the ring around the zenith of the central dome show that the Heavenly Liturgy was depicted here, specifically the Large Entrance which, aside from the communion, was the only part of the liturgy visible to the faithful. In Resava, the Heavenly Liturgy is completed by the images of crowds of angels, which are portrayed in the tambours of the side domes. The liturgical hymns that accompany these images of angels confirm this order. The rendering of orders of angels in the tambours of the side domes in Resava comply with the traditional program in which these heavenly beings - who being closest to God, who were his first creations and the only to whom a look in the

  8. Conceptual model for regional radionuclide transport from a salt dome repository: a technical memorandum

    Energy Technology Data Exchange (ETDEWEB)

    Kier, R.S.; Showalter, P.A.; Dettinger, M.D.

    1980-05-30

    Disposal of high-level radioactive wastes is a major environmental problem influencing further development of nuclear energy in this country. Salt domes in the Gulf Coast Basin are being investigated as repository sites. A major concern is geologic and hydrologic stability of candidate domes and potential transport of radionuclides by groundwater to the biosphere prior to their degradation to harmless levels of activity. This report conceptualizes a regional geohydrologic model for transport of radionuclides from a salt dome repository. The model considers transport pathways and the physical and chemical changes that would occur through time prior to the radionuclides reaching the biosphere. Necessary, but unknown inputs to the regional model involve entry and movement of fluids through the repository dome and across the dome-country rock interface and the effect on the dome and surrounding strata of heat generated by the radioactive wastes.

  9. Salinity Gradients for Sustainable Energy: Primer, Progress, and Prospects.

    Science.gov (United States)

    Yip, Ngai Yin; Brogioli, Doriano; Hamelers, Hubertus V M; Nijmeijer, Kitty

    2016-11-15

    Combining two solutions of different composition releases the Gibbs free energy of mixing. By using engineered processes to control the mixing, chemical energy stored in salinity gradients can be harnessed for useful work. In this critical review, we present an overview of the current progress in salinity gradient power generation, discuss the prospects and challenges of the foremost technologies - pressure retarded osmosis (PRO), reverse electrodialysis (RED), and capacitive mixing (CapMix) and provide perspectives on the outlook of salinity gradient power generation. Momentous strides have been made in technical development of salinity gradient technologies and field demonstrations with natural and anthropogenic salinity gradients (for example, seawater-river water and desalination brine-wastewater, respectively), but fouling persists to be a pivotal operational challenge that can significantly ebb away cost-competitiveness. Natural hypersaline sources (e.g., hypersaline lakes and salt domes) can achieve greater concentration difference and, thus, offer opportunities to overcome some of the limitations inherent to seawater-river water. Technological advances needed to fully exploit the larger salinity gradients are identified. While seawater desalination brine is a seemingly attractive high salinity anthropogenic stream that is otherwise wasted, actual feasibility hinges on the appropriate pairing with a suitable low salinity stream. Engineered solutions are foulant-free and can be thermally regenerative for application in low-temperature heat utilization. Alternatively, PRO, RED, and CapMix can be coupled with their analog separation process (reverse osmosis, electrodialysis, and capacitive deionization, respectively) in salinity gradient flow batteries for energy storage in chemical potential of the engineered solutions. Rigorous techno-economic assessments can more clearly identify the prospects of low-grade heat conversion and large-scale energy storage

  10. Deep radiostratigraphy of the East Antarctic plateau: connecting the Dome C and Vostok ice core sites

    OpenAIRE

    Cavitte, M; Blankenship, D; Young, D; Schroeder, D; F Parrenin; LeMeur, E; MacGregor, J.; Siegert, MJ

    2016-01-01

    International audience; Several airborne radar-sounding surveys are used to trace internal reflections around the European Project for Ice Coring in Antarctica Dome C and Vostok ice core sites. Thirteen reflections, spanning the last two glacial cycles, are traced within 200 km of Dome C, a promising region for million-year-old ice, using the University of Texas Institute for Geophysics High-Capacity Radar Sounder. This provides a dated stratigraphy to 2318 m depth at Dome C. Reflection age u...

  11. Seafloor doming driven by active mantle degassing offshore Naples (Italy)

    Science.gov (United States)

    Ventura, Guido; Passaro, Salvatore; Tamburrino, Stella; Vallefuoco, Mattia; Tassi, Franco; Vaselli, Orlando; Giannini, Luciano; Caliro, Stefano; Chiodini, Giovanni; Sacchi, Marco; Rizzo, Andrea

    2016-04-01

    Structures and processes associated with shallow water hydrothermal fluid discharges on continental shelves are poorly known. We report geomorphological, geophysical, and geochemical evidences of a 5.5 x 5.3 km seabed doming located 5 km offshore the Naples harbor (Italy). The dome lies between 100 and 170 m of water depth and it is 15-20 m higher than the surrounding seafloor. It is characterized by a hummocky morphology due to 280 sub-circular to elliptical mounds, about 660 cones, and 30 pockmarks. The mounds and pockmarks alignments follow those of the main structural discontinuity affecting the Gulf of Naples. The seafloor swelling and breaching require relatively low pressures (about 2-3 MPa), and the sub-seafloor structures, which consists of 'pagodas' affecting the present-day seabed, record the active upraise, pressurization, and release of magmatic fluids. The gas composition of the sampled submarine emissions is consistent with that of the emissions from the hydrothermal systems of Ischia, CampiFlegrei and Somma-Vesuvius active volcanoes, and CO2 has a magmatic/thermometamorphic origin. The 3He/4He ratios (1.66-1.96 Ra) are slightly lower than in the Somma-Vesuvius and Campi Flegrei volcanoes (~2.6-3.0 Ra) indicating the contamination of fluids originated from the same magmatic source by crustal-derived radiogenic 4He. All these evidences concur to hypothesize an extended magmatic reservoir beneath Naples and its offshore. Seabed doming, faulting, and hydrothermal discharges are manifestations of non-volcanic unrests potentially preluding submarine eruptions and/or hydrothermal explosions. We conclude that seabed deformations and hydrothermal discharge must be included in the coastal hazard studies.

  12. Development, characteristics and comparative structural analysis of tensegrity type cable domes

    National Research Council Canada - National Science Library

    Nenadović Aleksandra

    2010-01-01

    Tensegrity type cable domes are three-dimensional structural configurations, prestressed inside the perimeter compression ring, in which the continuous tension throughout the roof structure is made...

  13. Identifying and inventorying cypress domes in the Florida panhandle using Landsat imagery

    Science.gov (United States)

    Calaminus, Andre Kyle

    Cypress domes are swamp ecosystems dominated by pond cypress (Taxodium ascendens), a conifer native to North America. Cypress domes can be found in flatland depressions throughout the southeast United States, hydrologically separated from other water bodies. Threatened by urbanization and land use change, these unique ecosystems have experienced degradation, destruction, and habitat loss over the past few decades. While many domes have been identified in central and southern Florida, literature is lacking on cypress domes found in the Florida panhandle. Cypress domes within the Florida panhandle were located, inventoried, and analyzed for landscape patterns, including size and shape. Additionally, the cypress dome areas were subject to pixel change detection for temporal comparison of dome size from 2000 to 2013. Using satellite imagery from the Landsat 8 spacecraft, support vector machine classification, and publicly available data, a total of 1,568 cypress domes were found to exist in the Florida panhandle, with a mean area of 1.28 hectares, ranging from a minimum of 0.13 ha to a maximum of 4.95 ha, occupying 19.79 km2, or 0.078% of the panhandle study area. A change detection analysis over the 13 year period show a net gain of 284.63 ha in cypress dome growth.

  14. Spatial variations of growth within domes having different patterns of principal growth directions

    Directory of Open Access Journals (Sweden)

    Jerzy Nakielski

    2014-01-01

    Full Text Available Growth rate variations for two paraboloidal domes: A and B, identical when seen from the outside but differing in the internal pattern of principal growth directions, were modeled by means of the growth tensor and a natural coordinate system. In dome A periclinal trajectories in the axial plane were given by confocal parabolas (as in a tunical dome, in dome B by parabolas converging to the vertex (as in a dome without a tunica. Accordingly, two natural coordinate systems, namely paraboloidal for A and convergent parabolic for B, were used. In both cases, the rate of growth in area on the surfaces of domes was assumed to be isotropic and identical in corresponding points. It appears that distributions of growth rates within domes A and B are similar in their peripheral and central parts and different only in their distal regions. In the latter, growth rates are relatively large; the maximum relative rate of growth in volume is around the geometric focus in dome A, and on the surface around the vertex in dome B.

  15. A Planetarium Inside Your Office: Virtual Reality in the Dome Production Pipeline

    Science.gov (United States)

    Summers, Frank

    2018-01-01

    Producing astronomy visualization sequences for a planetarium without ready access to a dome is a distorted geometric challenge. Fortunately, one can now use virtual reality (VR) to simulate a dome environment without ever leaving one's office chair. The VR dome experience has proven to be a more than suitable pre-visualization method that requires only modest amounts of processing beyond the standard production pipeline. It also provides a crucial testbed for identifying, testing, and fixing the visual constraints and artifacts that arise in a spherical presentation environment. Topics adreesed here will include rendering, geometric projection, movie encoding, software playback, and hardware setup for a virtual dome using VR headsets.

  16. Lunar Domes With Concentric Radar-dark Deposits: Evidence For Pyroclastics?

    Science.gov (United States)

    Carter, Lynn M.; Hawke, B. R.; Campbell, B. A.

    2012-10-01

    The near side of the Moon has several areas with a high concentration of domes, which are evidence that some volcanic lavas were more viscous than the mare flood basalts that make up most of the lunar volcanic flows. Variable surface textures have been observed among the domes, which likely indicate a range of styles of late-stage volcanism, or possibly differences in how the erupted materials were altered over time. In particular, radar data of the domes reveal both very rough and very smooth surfaces. To date, very few domes have been found to have anomalously low radar circular polarization ratio (CPR) values that would suggest a coating of fine-grained pyroclastics. At S-band (12.6 cm wavelength), the Manilius 1 and Cauchy 5 domes have the lowest measured CPR values. We use a combination of ground-based radar data acquired with Arecibo Observatory and the Green Bank Telescope, Lunar Reconnaissance Orbiter (LRO) Camera images, and LRO Mini-RF radar data to map changes in surface textures across these features. The domes have very different morphologies. The Manilius 1 dome has a uniform, cratered surface with a circular central caldera, whereas the Cauchy 5 dome has very low topographic relief and an elongate central vent with jagged edges and pits similar to some features seen in high-resolution images of the unusual Ina D caldera. Although both domes have some similar radar reflection properties, they likely formed via significantly different processes.

  17. Flat Versus Hemispherical Dome Ports in Underwater Photogrammetry

    Science.gov (United States)

    Menna, F.; Nocerino, E.; Remondino, F.

    2017-02-01

    Underwater photogrammetry, like its counterpart in 'air', has gained an increasing diffusion thanks to the availability of easy-to-use, fast and often quite inexpensive software applications. Moreover, underwater equipment that allows the use of digital cameras normally designed to work in air also in water are largely available. However, for assuring accurate and reliable 3D modelling results a profound knowledge of the employed devices as well as physical and geometric principle is even more crucial than in air. This study aims to take a step forward in understanding the effect of underwater ports in front of the photographic lens. In particular, the effect of dome or flat ports on image quality in 3D modelling applications is investigated. Experiments conducted in a semi submerged indust rial structure show that the tested flat port performs worse than the dome, providing higher image residuals and lower precision and accuracy in object space. A significant different quality per colour channel is also observed and its influence on achievable processing results is discussed.

  18. The use of digital periapical radiographs to study the prevalence of alveolar domes

    Energy Technology Data Exchange (ETDEWEB)

    Xambre, Pedro Augusto Oliveira Santos; Valerio, Claudia Scigliano; Alves Cardoso, Claudia Assuncoe; Custodio, Antonio Luis Neto; Manzi, Flavio Ricardo [Dept. of Oral Radiology, School of Dentistry, Pontifical Catholic University of Minas Gerais, Belo Horizonte (Brazil)

    2016-09-15

    In the present study, we coined the term 'alveolar dome' and aimed to demonstrate the prevalence of alveolar domes through digital periapical radiographs. This study examined 800 digital periapical radiographs in regard to the presence of alveolar domes. The periapical radiographs were acquired by a digital system using a photostimulable phosphor (PSP) plate. The χ2 test, with a significance level of 5%, was used to compare the prevalence of alveolar domes in the maxillary posterior teeth and, considering the same teeth, to verify the difference in the prevalence of dome-shaped phenomena between the roots. The prevalence of alveolar domes present in the first pre-molars was statistically lower as compared to the other maxillary posterior teeth (p<0.05). No statistically significant difference was observed in the prevalence of alveolar domes between the maxillary first and second molars. Considering the maxillary first and second molars, it was observed that the palatal root presented a lower prevalence of alveolar domes when compared to the distobuccal and mesiobuccal roots (p<0.05). The present study coined the term 'alveolar dome', referring to the anatomical projection of the root into the floor of the maxillary sinus. The maxillary first and second molars presented a greater prevalence of alveolar domes, especially in the buccal roots, followed by the third molars and second pre-molars. Although the periapical radiograph is a two-dimensional method, it can provide dentists with the auxiliary information necessary to identify alveolar domes, thus improving diagnosis, planning, and treatment.

  19. The mythic structure in the black dome of the Haftpeikar: Study of Hero's journey in the first dome

    Directory of Open Access Journals (Sweden)

    Seyed Kazem Mousavi

    2016-12-01

    Full Text Available Abstract In this paper the Vogler Hero's journey is used for analyzing the mythic structures and hero's journey of the first dome of the Haftpeikar. Vogler Released his founds in the Writer's Journey book. This book that is really dependent on Campbell's Single Myth Theory is a practical guidance for script writing and review of that. The levels of the hero's journey in his book are include: The normal world, invitation to the story, reject the invitation, visit the mentor, passing the first gate, the exams, the allies, the enemies, qualifying to the deepest cave, trial, the reward, the road back, resurrection, return with the elixir.  In this paper, at first the properties of each level of the hero's journey theory are matching with the journey's levels in the black dome story. After that seven useful archetypes including hero, mentor, threshold guardian, herald, shape shifter, the shadow and trickster, are determined in the text.  Black dome has several journeys' cycles. Journey's that are seen in this dome are: (Bahram's journey: A part of the internal journey of Bahram in black dome. (The king's maid journey: Internal journey of the king's maid that wears black clothes after hearing the story. (King of black clothes' journey: The king's journey to the Madhooshan city for exploring the mystery of the black alien. (The reader's journey: This internal journey belongs to the readers of the first dome that learn their lessons through traveling to the character's world. (Nezami's journey: The Nezami's internal journey with composing the text. Checking the reader's journey and black dome's composer is out of this text. While the first and second journey just saying some parts, the black king has completer levels and for affecting on the other journeys is the most important story of the first dome. Therefore at first we check the black king story and we explain the other journeys.  The goal of this paper in addition to the usage of the vogler

  20. Structural Optimization of the Retractable Dome for Four Meter Telescope (FMT)

    Science.gov (United States)

    Pan, Nian; Li, Yuxi; Fan, Yue; Ma, Wenli; Huang, Jinlong; Jiang, Ping; Kong, Sijie

    2017-03-01

    Dome seeing degrades the image quality of ground-based telescopes. To achieve dome seeing of the Four Meter Telescope (FMT) less than 0.5 arcsec, structural optimizations based on computational fluid dynamics (CFD) simulation were proposed. The results of the simulation showed that dome seeing of FMT was 0.42 arcsec, which was mainly caused by the slope angle of the dome when the slope angle was 15° and the wind speed was 10 m/s. Furthermore, the lower the air speed was, the less dome seeing would be. Wind tunnel tests (WT) with a 1:120 scaled model of the retractable dome and FMT indicated that the calculated deviations of the CFD simulation used in this paper were less than 20% and the same variations of the refractive index derived from the WT would be a convincing argument for the validity of the simulations. Thus, the optimization of the retractable dome was reliable and the method expressed in this paper provided a reference for the design of next generation of ground-based telescope dome.

  1. Transparent Inflatable Column Film Dome for Nuclear Stations, Stadiums, and Cities

    Directory of Open Access Journals (Sweden)

    Alexander Bolonkin

    2011-01-01

    Full Text Available In a series of previous articles, one of the authors published designs of the AB Dome which can cover a city, important large installations or subregions by a transparent thin film supported by a small additional air overpressure. The AB Dome keeps the outside atmospheric conditions from the interior protecting a city from chemical, bacterial, and radioactive weapons (wastes. The design in this article differs from previous one as this design employs an inflatable columns which does not need an additional pressure (overpressure inside the dome and is cheaper in construction (no powered air pumping station and in operation (no special entrance airlock and permanent pumping expense. When dome is supported by columns, no overpressure is required inside the dome which is important when the dome covers a damaged nuclear reactor. The nuclear reactor may produce radioactive gases and dust, and, as inflatable domes are not typically hermetically sealed, the increased pressure inside the dome can leak out gas and dust into the atmosphere. The suggested design does not have this drawback. Positive pressure gradients expel dust particles—neutral pressure gradients will not. (Negative pressure gradients may even be possible in certain configurations.

  2. Growth rates of lava domes with respect to viscosity of magmas

    Directory of Open Access Journals (Sweden)

    I. Yokoyama

    2005-06-01

    Full Text Available In the discussion of lava dome formation, viscosity of magma plays an important role. Measurements of viscosity of magmas in field and laboratory are briefly summarized. The types of lava dome emplacements are classified into two, squeeze- and spine-type, by kinetic processes. The squeeze-type is the formation of a dome as a result of squeezes of magma through conduits and the latter is solidified magma forced to ascend by underlying fluid magma. An important parameter in the formation of such lava domes is their growth rates. Lava domes of squeeze-type are governed by the Hagen-Poiseuille Law which involves their viscosoties and other eruption parameters. At present, the real viscosity of magmas at the site of lava dome is still inaccessible. In order to avoid uncertainty in viscosity of magmas, a conception of «macroscopic viscosity» is proposed, which involves effects of chemical components, mainly SiO2 and volatile material, crystals and temperature, and their changes with time. Lava dome formations during the 20th century are briefly examined and their growth rates are estimated. The relationship between the growth rates and the SiO2 content of the magma is statistically studied, and the macroscopic viscosity is empirically expressed as a function of SiO2 content. The linearity between the two parameters is reasonably interpreted. This means that formation processes of lava domes are dominantly controlled by macroscopic viscosity of magma.

  3. Origins of Central Pits and Domes on Ceres: Dawn Mapping Constraints and Ganymede Comparisons

    Science.gov (United States)

    Schenk, P.; Hiesinger, H.; Platz, T.; Bowling, T.; Schmidt, B.; Sizemore, H.

    2017-09-01

    The bright faculae (spots) on Ceres are the most provocative features on this small planetary body and in Occator crater are associated with a prominent fractured dome and pit complex. This feature is analogous to those observed on large icy moon Ganymede and is potentially related to hydrothermal venting of carbonate-rich fluids followed by doming of the pit floor.

  4. Improved manufacturing techniques for rf and laser hardening of missile domes, phase 1

    Science.gov (United States)

    Pawlewicz, W. T.; Mann, I. B.; Martin, P. M.; Hays, D. D.; Graybeal, A. G.

    1982-07-01

    The adaptation of an existing Pacific Northwest Laboratory (PNL) optical coating capability developed for high power fusion laser applications to the case of RF and laser hardening of plastic missile domes used by US Army (MICOM) is reported. RF hardening of Hellfire and Copperhead 1.06 micron missile domes by use of transparent conductive Indium Tin Oxide (ITO) coatings is demonstrated. The project involved adaptation of a coating material and process developed for flat glass components used in fusion lasers to the case of hemispherical or conical heat sensitive plastic domes used on laser guided missiles. Specific ITO coating property goals are an electrical sheet resistance of 10 ohms/square, a coated dome transmission of 80% or more at 1.06 micron wavelength (compared to 90% for a bare dome), and good adhesion. The sheet resistance goal of 10 ohms/square was expected to result in an RF attenuation of 30 dB at the frequencies of importance.

  5. Effect of Pyramidal Dome Geometry on the Acoustical Characteristics in A Mosque

    Directory of Open Access Journals (Sweden)

    Dg. H. Kassim

    2014-12-01

    Full Text Available As an important symbol in Islam, a mosque is built with architectural grandeur. Among the characteristics is its high ceiling and it is usually constructed with a typical spherical dome shape. Some mosques, however, are influenced by the local culture and the dome can be of a different shape, such as pyramidal, as found in mosques in Malacca, Malaysia. This paper presents an assessment of the internal acoustical characteristics of a mosque having a pyramidal dome. The study is conducted by means of computer simulation using CATT indoor acoustic software. Reverberation time and clarity are taken to evaluate the intelligibility of speech. The effect of the angle and height of the dome on the acoustical parameters is discussed. It is found that a pyramidal dome with a steeper angle contributes to poor acoustic clarity.

  6. Sensitivity of storage field performance to geologic and cavern design parameters in salt domes.

    Energy Technology Data Exchange (ETDEWEB)

    Ehgartner, Brian L. (Sandia National Laboratories, Albuquerque, NM); Park, Byoung Yoon

    2009-03-01

    A sensitivity study was performed utilizing a three dimensional finite element model to assess allowable cavern field sizes for strategic petroleum reserve salt domes. A potential exists for tensile fracturing and dilatancy damage to salt that can compromise the integrity of a cavern field in situations where high extraction ratios exist. The effects of salt creep rate, depth of salt dome top, dome size, caprock thickness, elastic moduli of caprock and surrounding rock, lateral stress ratio of surrounding rock, cavern size, depth of cavern, and number of caverns are examined numerically. As a result, a correlation table between the parameters and the impact on the performance of storage field was established. In general, slower salt creep rates, deeper depth of salt dome top, larger elastic moduli of caprock and surrounding rock, and a smaller radius of cavern are better for structural performance of the salt dome.

  7. Design and test of an airborne IR countermeasures hyper-hemispherical silicon dome

    Science.gov (United States)

    Bender, Michael J.; Guyer, Robert C.; Fenton, Thomas E.

    2007-09-01

    A 6.5 inch diameter hyper-hemispherical silicon dome was developed on IRAD for an infrared countermeasures aircraft self-protection system. Having passed operational level environmental testing and many hours of flight performance, a prototype dome was subjected to MIL test requirements in simulated crash safety testing at the manufacturer's facility. Although the dome cracked during shock testing, it remained intact preserving aircraft integrity and actually passing safety requirements. This paper describes design requirements, stress analyses of the dome and its mounting, and test results including a forensic cause of failure study of the dome. The results add insight to the margins of safety normally applied to the stress analyses of brittle optical materials and examine actual cause of failure in the prototype part.

  8. Strategic Petroleum Reserve (SPR) geological site characterization report, Big Hill Salt Dome

    Energy Technology Data Exchange (ETDEWEB)

    Hart, R.J.; Ortiz, T.S.; Magorian, T.R.

    1981-09-01

    Geological and geophysical analyses of the Big Hill Salt Dome were performed to determine the suitability of this site for use in the Strategic Petroleum Reserve (SPR). Development of 140 million barrels (MMB) of storage capacity in the Big Hill Salt Dome is planned as part of the SPR expansion to achieve 750 MMB of storage capacity. Objectives of the study were to: (1) Acquire, evaluate, and interpret existing data pertinent to geological characterization of the Big Hill Dome; (2) Characterize the surface and near-surface geology and hydrology; (3) Characterize the geology and hydrology of the overlying cap rock; (4) Define the geometry and geology of the dome; (5) Determine the feasibility of locating and constructing 14 10-MMB storage caverns in the south portion of the dome; and (6) Assess the effects of natural hazards on the SPR site. Recommendations are included. (DMC)

  9. Out-of-plane doming behaviour from constrained auxetics

    Science.gov (United States)

    Attard, Daphne; Calleja, Dimitri; Grima, Joseph N.

    2018-01-01

    Auxetics expand laterally when uniaxially stretched. In many cases, this behaviour has been attributed to the interplay between the geometry of the system and its deformation mechanism. This work revisits a class of 2D motifs, the so-called chiral honeycombs, which are closely associated with auxetic behaviour. More specifically, we show that systems based on this motif, particularly those having a Poisson’s ratio of ‑1, can be engineered with specific constraints that limit the in-plane expansion, with the result that on inducing deformation of the systems, these veer out-of-plane to form dome-like structures. This effect is demonstrated in simple prototypes and it is shown through a simplified mathematical model that the extent of curvature can be controlled through the various parameters that describe such structures.

  10. Universal phase diagrams with superconducting domes for electronic flat bands

    Science.gov (United States)

    Löthman, Tomas; Black-Schaffer, Annica M.

    2017-08-01

    Condensed matter systems with flat bands close to the Fermi level generally exhibit, due to their very large density of states, extraordinarily high critical ordering temperatures of symmetry-breaking orders, such as superconductivity and magnetism. Here we show that the critical temperatures follow one of two universal curves with doping away from a flat band depending on the ordering channel, which completely dictates both the general order competition and the phase diagram. Notably, we find that orders in the particle-particle channel (superconducting orders) survive decisively farther than orders in the particle-hole channel (magnetic or charge orders) because the channels have fundamentally different polarizabilities. Thus, even if a magnetic or charge order initially dominates, superconducting domes are still likely to exist on the flanks of flat bands. We apply these general results to both the topological surface flat bands of rhombohedral ABC-stacked graphite and to the Van Hove singularity of graphene.

  11. Prospective Type Ia supernova surveys from Dome A

    Energy Technology Data Exchange (ETDEWEB)

    Kim, A.; Bonissent, A.; Christiansen, J. L.; Ealet, A.; Faccioli, L.; Gladney, L.; Kushner, G.; Linder, E.; Stoughton, C.; Wang, L.

    2010-03-10

    Dome A, the highest plateau in Antarctica, is being developed as a site for an astronomical observatory. The planned telescopes and instrumentation and the unique site characteristics are conducive toward Type Ia supernova surveys for cosmology. A self-contained search and survey over 5 years can yield a spectro-photometric time series of ~;; 1000 z< 0:08 supernovae. These can serve to anchor the Hubble diagram and quantify the relationship between luminosities and heterogeneities within the Type Ia supernova class, reducing systematics. Larger aperture (>=4-m) telescopes are capable of discovering supernovae shortly after explosion out to z ~;; 3. These can be fed to space telescopes, and can isolate systematics and extend the redshift range over which we measure the expansion history of the universe.

  12. Prospective Type Ia Supernova Surveys From Dome A

    Energy Technology Data Exchange (ETDEWEB)

    Kim, A.; /LBL, Berkeley; Bonissent, A.; /Marseille, CPPM; Christiansen, J.L.; /Cal. Poly.; Ealet, A.; /Marseille, CPPM; Faccioli, L.; /UC, Berkeley; Gladney, L.; /Pennsylvania U.; Kushner, G.; /LBL, Berkeley; Linder, E.; /UC, Berkeley; Stoughton, C.; /Fermilab; Wang, L.; /Texas A-M /Purple Mountain Observ.

    2010-02-01

    Dome A, the highest plateau in Antarctica, is being developed as a site for an astronomical observatory. The planned telescopes and instrumentation and the unique site characteristics are conducive toward Type Ia supernova surveys for cosmology. A self-contained search and survey over five years can yield a spectro-photometric time series of {approx}1000 z < 0.08 supernovae. These can serve to anchor the Hubble diagram and quantify the relationship between luminosities and heterogeneities within the Type Ia supernova class, reducing systematics. Larger aperture ({approx}>4-m) telescopes are capable of discovering supernovae shortly after explosion out to z {approx} 3. These can be fed to space telescopes, and can isolate systematics and extend the redshift range over which we measure the expansion history of the universe.

  13. Designing the SALT facility to minimize dome seeing effects

    Science.gov (United States)

    de Kock, Mariana; Venter, Sarel J.

    2003-02-01

    Aspects of the design and experience of the Hobby-Eberly Telescope (HET) were incorporated in the SALT facility design. The characteristics of the local environment were taken into account to ensure a building that is cost effective and functional. The effect of heat from the control room and other warm areas were studied and their locations changed to limit thermal effects. A steel false floor, incorporating forced ventilation and extending around the telescope azimuth pier, was installed. This prevents heat radiating from large concrete surfaces with temperatures potentially higher than ambient. Because site testing (i.e. micro thermal measurements) indicated high turbulence within ~5 m of the ground level, the telescope and pier were raised to improve dome seeing. The SALT site is significantly windy all year round (median velocity = 4.8 m/s), and this was utilized to design better ventilation of the facility using adjustable louvers for natural ventilation. Results of a computational fluid dynamic analysis (CFD) are presented which show an adequate temperature distribution at wind speeds as low as 0.5 m/s. The telescope chamber and dome are build out of insulation panels to ensure low thermal losses during the day when the chamber is air conditioned and thus limit electricity consumption and thermal gradients. Large equipment that emit heat or vibration are housed in a separate utility building 50 m from the telescope in the non-prevailing wind direction in order to limit their effect on the telescope. Vented air from the building is also released at this site.

  14. N-Acetylcysteine plus Saline Hydration versus Saline Hydration

    African Journals Online (AJOL)

    ) in patients undergoing coronary angiography pretreated with N-acetylcysteine NAC plus saline hydration or saline hydration alone and to determine the association between various risk factors and RCIN. Methods: Patients were ...

  15. under salinity stress

    African Journals Online (AJOL)

    ajl yemi

    2011-11-14

    Nov 14, 2011 ... (2002) reported that K and Zn deficiencies in the plant were mainly induced by soil salinity. Zhang et al. (2011) investigated the effects of applying different concentra- tions of the macronutrients K+, Ca2+ and Mg2+ on the responses of contrasting rice (O. sativa L.) genotypes under salt stress. A solution ...

  16. Real-Time Measurements of Aft Dome Insulation Erosion on Space Shuttle Reusable Solid Rocket Motor

    Science.gov (United States)

    McWhorter, Bruce; Ewing, Mark; Albrechtsen, Kevin; Noble, Todd; Longaker, Matt

    2004-01-01

    Real-time erosion of aft dome internal insulation was measured with internal instrumentation on a static test of a lengthened version of the Space Shuffle Reusable Solid Rocket Motor (RSRM). This effort marks the first time that real-time aft dome insulation erosion (Le., erosion due to the combined effects of thermochemical ablation and mechanical abrasion) was measured in this kind of large motor static test [designated as Engineering Test Motor number 3 (ETM3)I. This paper presents data plots of the erosion depth versus time. The data indicates general erosion versus time behavior that is in contrast to what would be expected from earlier analyses. Engineers have long known that the thermal environment in the aft dome is severe and that the resulting aft dome insulation erosion is significant. Models of aft dome erosion involve a two-step process of computational fluid dynamics (CFD) modeling and material ablation modeling. This modeling effort is complex. The time- dependent effects are difficult to verify with only prefire and postfire insulation measurements. Nozzle vectoring, slag accumulation, and changing boundary conditions will affect the time dependence of aft dome erosion. Further study of this data and continued measurements on future motors will increase our understanding of the aft dome flow and erosion environment.

  17. Polygenetic nature of a rhyolitic dome and implications for hazard assessment: Cerro Pizarro volcano, Mexico

    Science.gov (United States)

    Carrasco-Núñez, G.; Riggs, N. R.

    2008-04-01

    Rhyolitic domes are commonly regarded as monogenetic volcanoes associated with single, brief eruptions, in contrast to andesitic or dacitic domes that usually show a complex evolution including alternating long periods of growth and explosive destruction. Rhyolitic domes are characterized by short-lived successions of pyroclastic and effusive activity associated with a series of discrete eruptive events that apparently last on the order of years to decades or perhaps up to centuries. Cerro Pizarro, a rhyolitic dome in the eastern Mexican Volcanic Belt, is a relatively small (~ 1.1 km 3), isolated volcano that shows aspects of polygenetic volcanism including long-term repose periods (~ 50-80 ky) between eruptions, chemical variations over time, and a complex evolution of alternating explosive and effusive eruptions, including a cryptodome phase, a sector-collapse event and prolonged erosional processes. This eruptive behavior provides new insights into how rhyolite domes may evolve, in contrast to the traditional models of rhyolitic domes as short-lived, monogenetic systems. A protracted, complex evolution bears important implications for hazard assessment if reactivation of an apparently extinct rhyolitic dome must be seriously considered.

  18. The annual cycle and biological effects of the Costa Rica Dome

    Science.gov (United States)

    Fiedler, Paul C.

    2002-02-01

    The Costa Rica Dome is similar to other tropical thermocline domes in several respects: it is part of an east-west thermocline ridge associated with the equatorial circulation, surface currents flow cyclonically around it, and its seasonal evolution is affected by large-scale wind patterns. The Costa Rica Dome is unique because it is also forced by a coastal wind jet. Monthly climatological fields of thermocline depth and physical forcing variables (wind stress curl and surface current divergence) were analyzed to examine the structure and seasonal evolution of the dome. The annual cycle of the dome can be explained by wind forcing in four stages: (1) coastal shoaling of the thermocline off the Gulf of Papagayo during February-April, forced by Ekman pumping on the equatorward side of the Papagayo wind jet; (2) separation from the coast during May-June when the intertropical convergence zone (ITCZ) moves north to the countercurrent thermocline ridge, the wind jet stops, and the North Equatorial Countercurrent extends toward the coast on the equatorward flank of the ridge; (3) countercurrent thermocline ridging during July-November, when the dome expands to the west as the countercurrent thermocline ridge shoals beneath a band of cyclonic wind stress curl on the poleward side of the ITCZ; and (4) deepening during December-January when the ITCZ moves south and strong trade winds blow over the dome. Coastal eddies may be involved in the coastal shoaling observed during February-March. A seasonally predictable, strong, and shallow thermocline makes the Costa Rica Dome a distinct biological habitat where phytoplankton and zooplankton biomass are higher than in surrounding tropical waters. The physical structure and biological productivity of the dome affect the distribution and feeding of whales and dolphins, probably through forage availability.

  19. The need of alkalinity determination in the characterization of rain; Necesidad de la determinacion de la alcalinidad en la caracterizacion de la lluvia

    Energy Technology Data Exchange (ETDEWEB)

    Pal Verma, Mahendra [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-01-01

    In this paper is presented the alkalinity determination of the carbonic species in the rain waters by the Gran titration method. The alkalinity values obtained by this method in low electric conductivity waters are fairly reliable. Also, the existing studies on the characterization of acid rains, are discussed. [Espanol] En este trabajo se presenta la medicion de la alcalinidad y la determinacion de las especies carbonicas en las aguas de lluvia por el metodo de la titulacion de Gran. Los valores de alcalinidad obtenidos por este metodo en las aguas de baja conductividad electrica son bastante confiables. Asimismo, se discuten los estudios existentes sobre la caracterizacion de la lluvia acida en la republica mexicana.

  20. The stability of the dome of a liquid bubble rising in a dense liquid

    Science.gov (United States)

    Kanygin, R. I.; Kascheev, A. D.; Kudryavtsev, A. Yu; Meshkov, E. E.; Novikova, I. A.

    2018-02-01

    The results of experiments researching the stability of the dome of a large water bubble rising in a salt solution are presented. The experiments demonstrate the suppression of the Rayleigh–Taylor instability on the dome of the rising bubble with the Atwood number being A ≪ 1. The intensive development of the Kelvin–Helmholtz instability on the lateral surface of the bubble is observed as it rises. The stability of the dome of the rising bubble is explained by the action of an accelerated shear flow of water over the bubble surface. The results of computational modeling of the problem by the STAR-CCM + program are presented.

  1. Design and Test of Low-Profile Composite Aerospace Tank Dome

    Science.gov (United States)

    Ahmed, R.

    1999-01-01

    This report summarizes the design, analysis, manufacture, and test of a subscale, low-profile composite aerospace dome under internal pressure. A low-profile dome has a radius-to-height ratio greater than the square root of two. This effort demonstrated that a low-profile composite dome with a radius-to-height ratio of three was a feasible design and could adequately withstand the varying stress states resulting from internal pressurization. Test data for strain and displacement versus pressure are provided to validate the design.

  2. Seasonal variability in the input of lead, barium and indium to Law Dome, Antarctica

    DEFF Research Database (Denmark)

    Burn-Nunes...[], L.J.; Vallelonga, Paul Travis; Loss, R.D.

    2011-01-01

    Lead (Pb) isotopic compositions and concentrations, and barium (Ba) and indium (In) concentrations have been determined at monthly resolution in five Law Dome (coastal Eastern Antarctica) ice core sections dated from similar to 1757 AD to similar to 1898 AD. 'Natural' background Pb concentrations...... more impurity laden air from the Southern Hemisphere continental regions to Eastern Antarctica and Law Dome. As this Pb is isotopically identical to that emitted from south-eastern Australia (Broken Hill, Port Pine) this implies a relatively direct air trajectory pathway from southern Australia to Law...... Dome (Eastern Antarctica). (C) 2010 Elsevier Ltd. All rights reserved...

  3. Evolution of a complex isolated dome system, Cerro Pizarro, central México

    Science.gov (United States)

    Riggs, Nancy; Carrasco-Nunez, Gerardo

    Cerro Pizarro is an isolated rhyolitic dome in the intermontane Serdán-Oriental basin, located in the eastern Trans-Mexican Volcanic Belt. Cerro Pizarro erupted 1.1 km3 of magma at about 220 ka. Activity of Cerro Pizarro started with vent-clearing explosions at some depth; the resultant deposits contain clasts of local basement rocks, including Cretaceous limestone, 0.46-Ma welded tuff, and basaltic lava. Subsequent explosive eruptions during earliest dome growth produced an alternating sequence of surge and fallout layers from an inferred small dome. As the dome grew both vertically and laterally, it developed an external glassy carapace due to rapid chilling. Instability of the dome during emplacement caused the partial gravitational collapse of its flanks producing various block-and-ash-flow deposits. After a brief period of repose, re-injection of magma caused formation of a cryptodome with pronounced deformation of the vitrophyric dome and the underlying units to orientations as steep as near vertical. This stage began apparently as a gas-poor eruption and no explosive phases accompanied the emplacement of the cryptodome. Soon after emplacement of the cryptodome, however, the western flank of the edifice catastrophically collapsed, causing a debris avalanche. A hiatus in eruptive activity was marked by erosion of the cone and emplacement of ignimbrite derived from a caldera to the north of Cerro Pizarro. The final growth of the dome growth produced its present shape; this growth was accompanied by multiple eruptions producing surge and fallout deposits that mantle the topography around Cerro Pizarro. The evolution of the Cerro Pizarro dome holds aspects in common with classic dome models and with larger stratovolcano systems. We suggest that models that predict a simple evolution for domes fail to account for possibilities in evolutionary paths. Specifically, the formation of a cryptodome in the early stages of dome formation may be far more common than

  4. The control of saline groundwater

    NARCIS (Netherlands)

    Talsma, T.

    1963-01-01

    A study was made of the effect of the watertable, water-conducting properties of the soil, climatic factors and groundwater salinity on the salinization of soils in the Murrumbidgee Irrigation Areas, Australia.

    Average daily capillary flow rates were calculated from measured salinization (by

  5. Holocene Volcanic Records in the Siple Dome Ice Cores

    Science.gov (United States)

    Zielinski, G. A.; Dunbar, N. W.; Kurbatov, A. V.; Voisin, D. T.

    2001-12-01

    Using both the SO42- and Cl- time series and tephrochronological analyses, a highly detailed record of Holocene volcanism is being reconstructed from the Siple Dome A ice core. The volcanic glaciochemical record is being developed at a 2-4 year resolution for the last 10,000 years. Volcanic peaks were identified as those having a concentration of 2{σ } above the mean positive residual of the spline fit, as was done for the GISP2 volcanic record. We identified about 70 volcanic events for the mid-late Holocene. The largest sulfate signal (350 ppb) over the time period evaluated occurs at 2242 years ago. Large signals of volcanically enhanced sulfate in the ice core record also occur around 720 years ago (1280 C.E.;194-249 ppb)and 4710 years ago (378ppb). Ages for large equatorial or southern hemisphere volcanic eruptions are synchronous with identified sulfate peaks in the reconstructed volcanic record. However, the continuous scan for volcanic glass in these same samples yielded glass compositions more in-line with Antarctica volcanic zones (i.e., local eruptions). Nevertheless, our record provides important information on the atmospheric impact of volcanism in Antarctica geochemical cycles. The glass (i.e., tephra) found in various samples indicate that volcanoes within the McMurdo Volcanic Center (Victoria Land and the islands off its coast) including Mt. Melbourne, The Pleaides and Buckle Island appear to be the most active in Antarctica during the late Holocene. Rhyolitic shards of a composition not found in Antarctica also are present in some layers, although they are not overly abundant. The presence of dust with a Patagonian origin in East Antarctica ice cores as well as the nature of the Antarctica vortex indicate that material from this part of the southern hemisphere can reach various parts of Antarctica. Common circulation patterns around the Ross and Amundson Seas as well as the satellite trace of aerosols from the 1991 Cerro Hudson eruption, Argentina

  6. Internal Convection on Ceres: A Possible Explanation for Dome Formation

    Science.gov (United States)

    Travis, B. J.; Feldman, W. C.; Sizemore, H. G.; O'Brien, D. P.; Sykes, M. V.

    2015-12-01

    Numerical 2-D whole-body simulations of the evolution of Ceres' internal dynamics and thermal structure over its history indicate that hydrothermal activity is very strong throughout the first half of Ceres' history, gradually weakening thereafter, but still active even today (Travis et al, 2015, 46th LPSC). Large-scale upwelling plumes of muddy water extend from the porous, permeable rocky core through an ocean layer and impinge on the bottom of the ice shell. These upwellings are very long-lasting. In addition, small scale, shorter-lived plumes frequently develop on the upper regions of the large plumes. The large-scale plumes occur at roughly +/- 25 o latitude. Recently, 3-D simulations of a sector of Ceres shows that the upwellings are indeed plumes and not sheets. In the 3-D model, plume diameters in the model are as small as 15-20 km in diameter, up to several 10s of km or more. Relating internal dynamics to surface features is challenging. Linkage to mounds seen on the surface may be possible. There appear to be two classes of mounds: Large domes (10s of km diameter) and small (<15 km diameter). Morphological evidence such as embayment relations imply that large mounds may be extrusive. The source of the small domes is less clear. They could be extrusive, or they could be pingo-like structures that form when large areas of melt are extruded or produced by impact, although they are larger than terrestrial or martian structures. Mound heights are typically no more than 1 - 5 km. One mechanism for generation of these mounds suggested by our modeling is extrusion of mud through fractures in the icy crust. Over-pressuring of upwelling plumes at the base of the icy crust from freezing of neighboring downwellings could generate fractures in a frozen mud crust. As plumes and icy crust cool, a significant volume expansion occurs due to freezing of water to ice. This pressurization is not uniform in space; the still-liquid upwellings will experience overpressure in

  7. Percutaneous Radiofrequency Ablation with Artificial Ascites for Hepatocellular Carcinoma in the Hepatic Dome: Initial Experience

    National Research Council Canada - National Science Library

    Rhim, Hyunchul; Lim, Hyo K; Kim, Young-sun; Choi, Dongil

    2008-01-01

    ...) in the hepatic dome. MATERIALS AND METHODS. Sonographically guided percutaneous radiofrequency ablation with artificial ascites was performed in 25 patients with 34 HCCs using an internally cooled electrode radiofrequency system...

  8. Compactional deformation bands in Wingate Sandstone; additional evidence of an impact origin for Upheaval Dome, Utah

    Science.gov (United States)

    Okubo, Chris H.; Schultz, Richard A.

    2007-04-01

    Field and microstructural observations from Upheaval Dome, in Canyonlands National Park, Utah, show that inelastic strain of the Wingate Sandstone is localized along compactional deformation bands. These bands are tabular discontinuities (Jurassic) age for this impact.

  9. Digital Imaging for Siple Dome Ice Core Analysis, Antarctica, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains high-resolution digital images of thin and thick sections cut from the 1003 meter Siple Dome A main ice core. The images are useful for...

  10. Barnes Ice Cap South Dome Trilateration Net Survey Data 1970-1984, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Barnes Ice Cap data set contains survey measurements of a network of 43 stakes along a 10 km flow line on the northeast flank of the south dome of the Barnes Ice...

  11. Methyl Chloride Measurements from the Siple Dome A Deep Core, Antarctica, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set is an analysis of methyl chloride concentration measured in air extracted from ice core samples from the Siple Dome A deep core in West Antarctica. In...

  12. Methyl Chloride Measurements in the Taylor Dome M3C1 Ice Core, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set includes methyl chloride (CH3CI) measurements made on air extracted from 62 samples from the Taylor Dome M3C1 ice core in East Antarctica. CH3CI was...

  13. Annual Layers at Siple Dome, Antarctica, from Borehole Optical Stratigraphy, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — Researchers gathered data on annual snow layers at Siple Dome, Antarctica, using borehole optical stratigraphy. This data set contains annual layer depths and firn...

  14. Hyperthyroidism with dome-and-dart T wave: A case report: A care-compliant article.

    Science.gov (United States)

    Lai, Ping; Yuan, Jing-Ling; Xue, Jin-Hua; Qiu, Yue-Qun

    2017-02-01

    Dome-and-dart T waves (or bifid T waves) are a rare phenomenon in the surface electrocardiogram. These wave forms are mainly observed in patients with congenital heart disease such as atrial septal defect and ventricular septal defect. And hyperthyroidism who presented with an electrocardiogram that had dome-and-dart T waves in a precordial lead is never been reported. The patient presented with continuous tachycardia, palpitations, chest tightness, and headache for 4 days, and aggravated for 1 day. Hyperthyroidism. Methimazole. All symptoms were alleviated. Dome-and-dart or bifid T waves have been reported in the conventional 12-lead electrocardiograms in some patients with congenital heart disease. The case illustrated here, to the best of our knowledge, dome-and-dart or bifid T waves may associate with hyperthyroidism patients.

  15. Dome-shaped High Tibial Osteotomy: A Long-term Follow-up Study

    Directory of Open Access Journals (Sweden)

    Hongsen Chiang

    2006-01-01

    Conclusion: Dome-shaped HTO is a durable time-buying procedure for patients with unicompartmental medial gonarthrosis, and can avoid subsequent development of patella baja that may complicate further prosthetic arthroplasty.

  16. LA-ICP-MS Results: 3 Siple Dome A Glacial Age Archives, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the results of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) performed on an archive of the Siple Dome A ice core...

  17. Methane Measurements from the GISP2 and Siple Dome Ice Cores, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains methane measurements made in trapped air in the Holocene sections of two ice cores: the Siple Dome ice core in Antarctica, and the Greenland...

  18. Tree-mediated methane emissions along a tropical peat dome

    Science.gov (United States)

    Pangala, Sunitha; Hoyt, Alison; Cobb, Alex; Harvey, Charles; Gauci, Vincent

    2017-04-01

    Methane production and transport processes in peatlands are fairly well understood, but growing evidence for emission of methane through trees has highlighted the need to revisit methane transport processes. We examined methane emissions from all pathways including stem and leaf emissions in one of the last remaining pristine tropical peatlands in Southeast Asia: Belait peat swamp forests, Brunei Darussalam. Methane emissions along with a range of biotic and abiotic factors were measured within three 20 x 30 m plots along transects from the edge to the center of the peat done which is dominated by Shorea albida. Tree-mediated methane emissions were the dominant means of methane emissions from all three plots, with soil emissions equating to less than 30% of the total ecosystem methane flux. Both tree and soil emissions varied between and within the three plots, with soil emissions decreasing from the edge to the center of the peat dome with increasing peat depth and decreasing water table depths and tree emissions following an opposite trend. Within each plot, tree-mediated methane emissions displayed large variability with fluxes ranging between 0.2 - 9.4 mg m-2 hr-1. Relationships between tree-mediated methane emissions and pore-water methane concentrations point towards the possibility of some of these trees transporting methane produced in the deeper layers of the peat profile to the atmosphere. Taken together, these observations highlight that methane emissions through tree stems play a more central role in methane cycling in tropical peatlands.

  19. Authentic Astronomical Discovery in Planetariums: Bringing Data to Domes

    Science.gov (United States)

    Wyatt, Ryan Jason; Subbarao, Mark; Christensen, Lars; Emmons, Ben; Hurt, Robert

    2018-01-01

    Planetariums offer a unique opportunity to disseminate astronomical discoveries using data visualization at all levels of complexity: the technical infrastructure to display data and a sizeable cohort of enthusiastic educators to interpret results. “Data to Dome” is an initiative the International Planetarium Society to develop our community’s capacity to integrate data in fulldome planetarium systems—including via open source software platforms such as WorldWide Telescope and OpenSpace. We are cultivating a network of planetarium professionals who integrate data into their presentations and share their content with others. Furthermore, we propose to shorten the delay between discovery and dissemination in planetariums. Currently, the “latest science” is often presented days or weeks after discoveries are announced, and we can shorten this to hours or even minutes. The Data2Dome (D2D) initiative, led by the European Southern Observatory, proposes technical infrastructure and data standards that will streamline content flow from research institutions to planetariums, offering audiences a unique opportunity to access to the latest astronomical data in near real time.

  20. Design Of a Fixed-Dome Ferrocement Biodigester Built Partiall y Underground

    OpenAIRE

    Marianela de la Caridad Ortiz Alvarez; Hugo Rafael Wainshtok Rivas; Henry Hernández Sotomayor

    2016-01-01

    The analysis, structural design and constructive sequence of a fixed-dome biodigester built partially underground and using ferrocement as construction material under normal work conditions is in this paper developed. The biodigester capacity is 24 m3 and it is composed by a semispherical dome (cover), cylindricalwalls (body) and a circular slab(bottom). The biodigester using ferrocement as construction materialis in agreement with the service guaranty requirements settled for the established...

  1. Imbrian-age highland volcanism on the moon - The Gruithuisen and Mairan domes

    Science.gov (United States)

    Head, J. W., III; Mccord, T. B.

    1978-01-01

    The Gruithuisen and Mairan domes on the moon represent morphologically and spectrally distinct nonmare extrusive volcanic features of Imbrian age. The composition, morphology, and age relationships of the domes indicate that nonmare extrusive volcanism in the northern Procellarum region of the moon continued until about 3.3 x 10 to the 9th to 3.6 x 10 to the 9th years ago and was partially contemporaneous with the emplacement of the main sequence of mare deposits.

  2. DOMe: A deduplication optimization method for the NewSQL database backups.

    Directory of Open Access Journals (Sweden)

    Longxiang Wang

    Full Text Available Reducing duplicated data of database backups is an important application scenario for data deduplication technology. NewSQL is an emerging database system and is now being used more and more widely. NewSQL systems need to improve data reliability by periodically backing up in-memory data, resulting in a lot of duplicated data. The traditional deduplication method is not optimized for the NewSQL server system and cannot take full advantage of hardware resources to optimize deduplication performance. A recent research pointed out that the future NewSQL server will have thousands of CPU cores, large DRAM and huge NVRAM. Therefore, how to utilize these hardware resources to optimize the performance of data deduplication is an important issue. To solve this problem, we propose a deduplication optimization method (DOMe for NewSQL system backup. To take advantage of the large number of CPU cores in the NewSQL server to optimize deduplication performance, DOMe parallelizes the deduplication method based on the fork-join framework. The fingerprint index, which is the key data structure in the deduplication process, is implemented as pure in-memory hash table, which makes full use of the large DRAM in NewSQL system, eliminating the performance bottleneck problem of fingerprint index existing in traditional deduplication method. The H-store is used as a typical NewSQL database system to implement DOMe method. DOMe is experimentally analyzed by two representative backup data. The experimental results show that: 1 DOMe can reduce the duplicated NewSQL backup data. 2 DOMe significantly improves deduplication performance by parallelizing CDC algorithms. In the case of the theoretical speedup ratio of the server is 20.8, the speedup ratio of DOMe can achieve up to 18; 3 DOMe improved the deduplication throughput by 1.5 times through the pure in-memory index optimization method.

  3. Effects of salinity on leaf breakdown: Dryland salinity versus salinity from a coalmine.

    Science.gov (United States)

    Sauer, Felix G; Bundschuh, Mirco; Zubrod, Jochen P; Schäfer, Ralf B; Thompson, Kristie; Kefford, Ben J

    2016-08-01

    Salinization of freshwater ecosystems as a result of human activities represents a global threat for ecosystems' integrity. Whether different sources of salinity with their differing ionic compositions lead to variable effects in ecosystem functioning is unknown. Therefore, the present study assessed the impact of dryland- (50μS/cm to 11,000μS/cm) and coalmine-induced (100μS/cm to 2400μS/cm) salinization on the leaf litter breakdown, with focus on microorganisms as main decomposer, in two catchments in New South Wales, Australia. The breakdown of Eucalyptus camaldulensis leaves decreased with increasing salinity by up to a factor of three. Coalmine salinity, which is characterised by a higher share of bicarbonates, had a slightly but consistently higher breakdown rate at a given salinity relative to dryland salinity, which is characterised by ionic proportions similar to sea water. Complementary laboratory experiments supported the stimulatory impact of sodium bicarbonates on leaf breakdown when compared to sodium chloride or artificial sea salt. Furthermore, microbial inoculum from a high salinity site (11,000μS/cm) yielded lower leaf breakdown at lower salinity relative to inoculum from a low salinity site (50μS/cm). Conversely, inoculum from the high salinity site was less sensitive towards increasing salinity levels relative to inoculum from the low salinity site. The effects of the different inoculum were the same regardless of salt source (sodium bicarbonate, sodium chloride and artificial sea salt). Finally, the microorganism-mediated leaf litter breakdown was most efficient at intermediate salinity levels (≈500μS/cm). The present study thus points to severe implications of increasing salinity intensities on the ecosystem function of leaf litter breakdown, while the underlying processes need further scrutiny. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  4. A comparison between semi-spheroid- and dome-shaped quantum dots coupled to wetting layer

    Energy Technology Data Exchange (ETDEWEB)

    Shahzadeh, Mohammadreza; Sabaeian, Mohammad, E-mail: Sabaeian@scu.ac.ir [Physics Department, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, 61357-43135 (Iran, Islamic Republic of)

    2014-06-15

    During the epitaxial growth method, self-assembled semi-spheroid-shaped quantum dots (QDs) are formed on the wetting layer (WL). However for sake of simplicity, researchers sometimes assume semi-spheroid-shaped QDs to be dome-shaped (hemisphere). In this work, a detailed and comprehensive study on the difference between electronic and transition properties of dome- and semi-spheroid-shaped quantum dots is presented. We will explain why the P-to-S intersubband transition behaves the way it does. The calculated results for intersubband P-to-S transition properties of quantum dots show two different trends for dome-shaped and semi-spheroid-shaped quantum dots. The results are interpreted using the probability of finding electron inside the dome/spheroid region, with emphasis on the effects of wetting layer. It is shown that dome-shaped and semi-spheroid-shaped quantum dots feature different electronic and transition properties, arising from the difference in lateral dimensions between dome- and semi-spheroid-shaped QDs. Moreover, an analogy is presented between the bound S-states in the quantum dots and a simple 3D quantum mechanical particle in a box, and effective sizes are calculated. The results of this work will benefit researchers to present more realistic models of coupled QD/WL systems and explain their properties more precisely.

  5. Is there 1.5-million-year-old ice near Dome C, Antarctica?

    Science.gov (United States)

    Parrenin, Frédéric; Cavitte, Marie G. P.; Blankenship, Donald D.; Chappellaz, Jérôme; Fischer, Hubertus; Gagliardini, Olivier; Masson-Delmotte, Valérie; Passalacqua, Olivier; Ritz, Catherine; Roberts, Jason; Siegert, Martin J.; Young, Duncan A.

    2017-11-01

    Ice sheets provide exceptional archives of past changes in polar climate, regional environment and global atmospheric composition. The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC), reaching ˜ 800 000 years. Obtaining an older paleoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we use internal isochrones, identified from airborne radar coupled to ice-flow modelling to estimate the age of basal ice along transects in the Dome C area. Three glaciological properties are inferred from isochrones: surface accumulation rate, geothermal flux and the exponent of the Lliboutry velocity profile. We find that old ice (> 1.5 Myr, 1.5 million years) likely exists in two regions: one ˜ 40 km south-west of Dome C along the ice divide to Vostok, close to a secondary dome that we name Little Dome C (LDC), and a second region named North Patch (NP) located 10-30 km north-east of Dome C, in a region where the geothermal flux is apparently relatively low. Our work demonstrates the value of combining radar observations with ice flow modelling to accurately represent the true nature of ice flow, and understand the formation of ice-sheet architecture, in the centre of large ice sheets.

  6. Distributions of cranial pathologies provide evidence for head-butting in dome-headed dinosaurs (Pachycephalosauridae).

    Science.gov (United States)

    Peterson, Joseph E; Dischler, Collin; Longrich, Nicholas R

    2013-01-01

    Pachycephalosaurids are small, herbivorous dinosaurs with domed skulls formed by massive thickening of the cranial roof. The function of the dome has been a focus of debate: the dome has variously been interpreted as the product of sexual selection, as an adaptation for species recognition, or as a weapon employed in intraspecific combat, where it was used in butting matches as in extant ungulates. This last hypothesis is supported by the recent identification of cranial pathologies in pachycephalosaurids, which appear to represent infections resulting from trauma. However, the frequency and distribution of pathologies have not been studied in a systematic fashion. Here, we show that pachycephalosaurids are characterized by a remarkably high incidence of cranial injury, where 22% of specimens have lesions on the dome. Frequency of injury shows no significant difference between different genera, but flat-headed morphs (here interpreted as juveniles or females) lack lesions. Mapping of injuries onto a digitial pachycephalosaurid skull shows that although lesions are distributed across the dome, they cluster near the apex, which is consistent with the hypothesis that the dome functioned for intraspecific butting matches.

  7. Is there 1.5-million-year-old ice near Dome C, Antarctica?

    Directory of Open Access Journals (Sweden)

    F. Parrenin

    2017-11-01

    Full Text Available Ice sheets provide exceptional archives of past changes in polar climate, regional environment and global atmospheric composition. The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC, reaching ∼ 800 000 years. Obtaining an older paleoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we use internal isochrones, identified from airborne radar coupled to ice-flow modelling to estimate the age of basal ice along transects in the Dome C area. Three glaciological properties are inferred from isochrones: surface accumulation rate, geothermal flux and the exponent of the Lliboutry velocity profile. We find that old ice (> 1.5 Myr, 1.5 million years likely exists in two regions: one ∼ 40 km south-west of Dome C along the ice divide to Vostok, close to a secondary dome that we name Little Dome C (LDC, and a second region named North Patch (NP located 10–30 km north-east of Dome C, in a region where the geothermal flux is apparently relatively low. Our work demonstrates the value of combining radar observations with ice flow modelling to accurately represent the true nature of ice flow, and understand the formation of ice-sheet architecture, in the centre of large ice sheets.

  8. A Cascade of Wnt, Eda, and Shh Signaling Is Essential for Touch Dome Merkel Cell Development.

    Directory of Open Access Journals (Sweden)

    Ying Xiao

    2016-07-01

    Full Text Available The Sonic hedgehog (Shh signaling pathway regulates developmental, homeostatic, and repair processes throughout the body. In the skin, touch domes develop in tandem with primary hair follicles and contain sensory Merkel cells. The developmental signaling requirements for touch dome specification are largely unknown. We found dermal Wnt signaling and subsequent epidermal Eda/Edar signaling promoted Merkel cell morphogenesis by inducing Shh expression in early follicles. Lineage-specific gene deletions revealed intraepithelial Shh signaling was necessary for Merkel cell specification. Additionally, a Shh signaling agonist was sufficient to rescue Merkel cell differentiation in Edar-deficient skin. Moreover, Merkel cells formed in Fgf20 mutant skin where primary hair formation was defective but Shh production was preserved. Although developmentally associated with hair follicles, fate mapping demonstrated Merkel cells primarily originated outside the hair follicle lineage. These findings suggest that touch dome development requires Wnt-dependent mesenchymal signals to establish reciprocal signaling within the developing ectoderm, including Eda signaling to primary hair placodes and ultimately Shh signaling from primary follicles to extrafollicular Merkel cell progenitors. Shh signaling often demonstrates pleiotropic effects within a structure over time. In postnatal skin, Shh is known to regulate the self-renewal, but not the differentiation, of touch dome stem cells. Our findings relate the varied effects of Shh in the touch dome to the ligand source, with locally produced Shh acting as a morphogen essential for lineage specification during development and neural Shh regulating postnatal touch dome stem cell maintenance.

  9. Features of Bayou Choctaw SPR caverns and internal structure of the salt dome.

    Energy Technology Data Exchange (ETDEWEB)

    Munson, Darrell E.

    2007-07-01

    The intent of this study is to examine the internal structure of the Bayou Choctaw salt dome utilizing the information obtained from graphical representations of sonar survey data of the internal cavern surfaces. Many of the Bayou Choctaw caverns have been abandoned. Some existing caverns were purchased by the Strategic Petroleum Reserve (SPR) program and have rather convoluted histories and complex cavern geometries. In fact, these caverns are typically poorly documented and are not particularly constructive to this study. Only two Bayou Choctaw caverns, 101 and 102, which were constructed using well-controlled solutioning methods, are well documented. One of these was constructed by the SPR for their use while the other was constructed and traded for another existing cavern. Consequently, compared to the SPR caverns of the West Hackberry and Big Hill domes, it is more difficult to obtain a general impression of the stratigraphy of the dome. Indeed, caverns of Bayou Choctaw show features significantly different than those encountered in the other two SPR facilities. In the number of abandoned caverns, and some of those existing caverns purchased by the SPR, extremely irregular solutioning has occurred. The two SPR constructed caverns suggest that some sections of the caverns may have undergone very regular solutioning to form uniform cylindrical shapes. Although it is not usually productive to speculate, some suggestions that point to the behavior of the Bayou Choctaw dome are examined. Also the primary differences in the Bayou Choctaw dome and the other SPR domes are noted.

  10. Strategic petroleum reserve, Byran Mound Salt Dome, Brazoria County, Texas. Final environmental impact statement (final supplement to FEA FES 76/77-6)

    Energy Technology Data Exchange (ETDEWEB)

    1977-12-01

    On January 7, 1977, the Federal Energy Administration issued a Final Environmental Impact Statement (EIS) for the development of the Bryan Mound salt dome as a storage site for the Strategic Petroleum Reserve (FES 76/77-6). On October 1, 1977, the U.S. Department of Energy was created and the programs of the Federal Energy Administration were transferred to the new Department. As such, this final supplement is being issued by the Department of Energy. The salt dome is located in Brazoria County, Texas. Since the EIS was published, it has been determined that this arrangement would be inadequate to meet the long term requirements for filling and withdrawing oil at the site, although the disposal of brine to Dow Chemical would be utilized to the maximum extent possible. Therefore, on July 15, 1977, a Draft Supplement to FES 76/77-6 was issued addressing the environmental impacts of construction and operation of two types of brine disposal systems and a new water supply system. This final supplement addresses a brine injection well system and a water intake system. Construction of this new system component would cause temporary disruption to land use, water quality, air quality, and terrestrial and aquatic ecology. The new facilities would permanently change 17 acres of land from its present use. Operation of the systems would have relatively small, short-term impacts. Use of the brine surge pit could adversely affect air quality by emitting hydrocarbon vapors (maximum rate of 51.4 tons per year). Operation of the disposal wells would increase the salinity of an already saline aquifer. All operational impacts would be relatively minor and short-term, occurring only during periods of fill or withdrawal of the storage facility.

  11. Late Miocene uplift and doming of Madagascar: topographic implications

    Science.gov (United States)

    Delaunay, Antoine; Robin, Cecile; Guillocheau, François; Dall'Asta, Massimo; Calves, Gérôme

    2016-04-01

    and (3) a major stepping of dated planation surfaces. (3) The end result of this uplift is a convex up shape pattern for the end Cretaceous surface weathered during Eocene times, creating the present-day dome morphology (with a central plateau) of Madagascar. (4) The amplitude of this uplift can be estimated based on the present-day elevation of Late Eocene lagoonal sediments located 100 km north-east of Toliara and now at an elevation of 900m. If the absolute sea level was around 50 m (Miller et al., 2005) above present-day sea level during Late Eocene times, this means a surface uplift of around 850 m. (5) The mechanism of this uplift has to explain a very long wavelength deformation (x1000 km) necessary due to mantle dynamics. The relationships with the other East African domes (Ethiopia, East Africa, South Africa) are discussed. This study was founded by TOTAL and IFREMER in the frame of the research project PAMELA (Passive Margin Exploration Laboratories).

  12. Manufacturing and metrology for IR conformal windows and domes

    Science.gov (United States)

    Ferralli, Ian; Blalock, Todd; Brunelle, Matt; Lynch, Timothy; Myer, Brian; Medicus, Kate

    2017-05-01

    Freeform and conformal optics have the potential to dramatically improve optical systems by enabling systems with fewer optical components, reduced aberrations, and improved aerodynamic performance. These optical components differ from standard components in their surface shape, typically a non-symmetric equation based definition, and material properties. Traditional grinding and polishing tools are unable to handle these freeform shapes. Additionally, standard metrology tools cannot measure these surfaces. Desired substrates are typically hard ceramics, including poly-crystalline alumina or aluminum oxynitride. Notwithstanding the challenges that the hardness provides to manufacturing, these crystalline materials can be highly susceptible to grain decoration creating unacceptable scatter in optical systems. In this presentation, we will show progress towards addressing the unique challenges of manufacturing conformal windows and domes. Particular attention is given to our robotic polishing platform. This platform is based on an industrial robot adapted to accept a wide range of tooling and parts. The robot's flexibility has provided us an opportunity to address the unique challenges of conformal windows. Slurries and polishing active layers can easily be changed to adapt to varying materials and address grain decoration. We have the flexibility to change tool size and shape to address the varying sizes and shapes of conformal optics. In addition, the robotic platform can be a base for a deflectometry-based metrology tool to measure surface form error. This system, whose precision is independent of the robot's positioning accuracy, will allow us to measure optics in-situ saving time and reducing part risk. In conclusion, we will show examples of the conformal windows manufactured using our developed processes.

  13. Public Education and Outreach Through Full-Dome Video Technology

    Science.gov (United States)

    Pollock, John

    2009-03-01

    My long-term goal is to enhance public understanding of complex systems that can be best demonstrated through richly detailed computer graphic animation displayed with full-dome video technology. My current focus is on health science advances that focus on regenerative medicine, which helps the body heal itself. Such topics facilitate science learning and health literacy. My team develops multi-media presentations that bring the scientific and medical advances to the public through immersive high-definition video animation. Implicit in treating the topics of regenerative medicine will be the need to address stem cell biology. The topics are clarified and presented from a platform of facts and balanced ethical consideration. The production process includes communicating scientific information about the excitement and importance of stem cell research. Principles of function are emphasized over specific facts or terminology by focusing on a limited, but fundamental set of concepts. To achieve this, visually rich, biologically accurate 3D computer graphic environments are created to illustrate the cells, tissues and organs of interest. A suite of films are produced, and evaluated in pre- post-surveys assessing attitudes, knowledge and learning. Each film uses engaging interactive demonstrations to illustrate biological functions, the things that go wrong due to disease and disability, and the remedy provided by regenerative medicine. While the images are rich and detailed, the language is accessible and appropriate to the audience. The digital, high-definition video is also re-edited for presentation in other ``flat screen'' formats, increasing our distribution potential. Show content is also presented in an interactive web space (www.sepa.duq.edu) with complementing teacher resource guides and student workbooks and companion video games.

  14. Prototype study of characterization of the impact that produces the diffuser of an industrial discharge into the sea water; Estudio prototipo de caracterizacion del impacto que produce el difusor de una descarga industrial sobre el medio marino

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz Gallarza, S. M.; Gil Zurita, A.; Garcia Hernandez, R.; Vergara Mendez, S.; Garcia Leal, M. L. [Universidad Autonoma Metropolitana, Mexico, D.F. (Mexico)

    2000-09-01

    To establish maximum permissible limits of pollutants discharged into the sea from industrial wastewater, the authorities involved in the environmental protection and regulation had established particular characteristic for their discharges in each enterprise. In addition to taking care of the conservation of those limits, the effect of these substances on the environment needs to be evaluated. Along this line, integral multidisciplinary studies of impact characterization on the marine environment induced by the industry have been carried out. One of the industrial enterprises that discharges into the northwestern coastline of the Gulf of Mexico through a submarine diffuser, requested the execution of the first study of this kind. This prototype study included physical, chemical, biological and geological determinations in a network of 49 sampling sites along six transects positioned from a boat, and with theodolites from the coast; covering five depth levels (surface, 4, 8, 12 and 16 m) during rainy, dry and northern winds seasons. Heavy metals in the water, sediments, and organisms and in combined samples of the industrial discharge were determined. Continuous measurements of marine currents, salinity and temperature in the nozzles of the diffuser were performed by means of two S4 Inter Ocean current meters. Helicopters flights were made to observe the displacement variations of the pollutants plume under various climatic conditions. LANDSAT TM satellite images were acquired to obtain information on diverse regions of the electromagnetic spectrum and to verify observations on the behavior of the discharge plume. Besides the conventional methods of plotting and information processing, tri-dimensional visualization was applied with the purpose of interpreting seasonal and diffusion patterns. Because of the excellent results obtained with this methodology, this study is made available to specialists as a prototype for determining the coastal marine environmental

  15. Salinity tolerance in halophytes.

    Science.gov (United States)

    Flowers, Timothy J; Colmer, Timothy D

    2008-01-01

    Halophytes, plants that survive to reproduce in environments where the salt concentration is around 200 mm NaCl or more, constitute about 1% of the world's flora. Some halophytes show optimal growth in saline conditions; others grow optimally in the absence of salt. However, the tolerance of all halophytes to salinity relies on controlled uptake and compartmentalization of Na+, K+ and Cl- and the synthesis of organic 'compatible' solutes, even where salt glands are operative. Although there is evidence that different species may utilize different transporters in their accumulation of Na+, in general little is known of the proteins and regulatory networks involved. Consequently, it is not yet possible to assign molecular mechanisms to apparent differences in rates of Na+ and Cl- uptake, in root-to-shoot transport (xylem loading and retrieval), or in net selectivity for K+ over Na+. At the cellular level, H+-ATPases in the plasma membrane and tonoplast, as well as the tonoplast H+-PPiase, provide the trans-membrane proton motive force used by various secondary transporters. The widespread occurrence, taxonomically, of halophytes and the general paucity of information on the molecular regulation of tolerance mechanisms persuade us that research should be concentrated on a number of 'model' species that are representative of the various mechanisms that might be involved in tolerance.

  16. LED package with Dome/side-emitting-enhancement silicone lens achieved by dispensing and geometry transferring

    Science.gov (United States)

    Chang Chien, Chien-Lin; Huang, Yu-Che; Hu, Syue-Fong; Sun, Chang-Wen; Chang, Chung-Min; Hsu, Chih-Peng; Yip, Ming-Chuen; Fang, Weileun

    2012-10-01

    This study presents a structure design and process method for lens type LED package. Dome type or side-emitting-enhancement silicone lens without molding process are achieved. The ceramic ring is adopted as the confine for the encapsulant. The surface intension along the sidewall of ceramic ring and silicone surface, the cohesion force and the gravity of silicone determine the shape of dome type silicone lens. The cone shape tooling coated with a releasing material is immersed into the dome type silicone lens before the silicone fully hardening. After curing simultaneously, to remove the tooling from package, the package with side-emitting-enhancement silicone lens is finished. With the mentioned architecture and process, this LED package herein has three merits, (1) to improve light extraction efficiency: reduce the chance of total internal reflection by the geometry of dome type silicone lens. (2)To enhance the flexibility of LED package design, the die placement location would be constrained by the mold in the traditional package process. (3) Mold-less side-emitting-enhancement silicone lens. Furthermore, two types of cone shape tooling are implemented and compared for side-emitting-enhancement silicone lens. Measurement results show the ratio between the lens high and lens radius could achieve 0.9:1. The view angles of dome type and side-emitting-enhancement LED packaged devices can reach 153° and 180 °, respectively. As using the same brightness grade of LED chip, the luminous flux is increasing 15% as compared the dome type package with the commercial PLCC (Plastic Leaded Chip Carrier) type package. The luminous flux of side-emitting-enhancement LED package decreases 8% as compared with the dome type one.

  17. New Approaches to Inferences for Steep-Sided Domes on Venus

    Science.gov (United States)

    Quick, Lynnae C.; Glaze, Lori S.; Baloga, Stephen; Stofan, Ellen

    2016-01-01

    New mathematical approaches for the relaxation and emplacement of viscous lava domes are presented and applied to steep-sided domes on Venus. A similarity solution approach is applied to the governing equation for fluid flow in a cylindrical geometry for two distinct scenarios. In the first scenario, dome relaxation is explored assuming a constant volume of fluid (i.e. lava) has been rapidly emplaced onto the surface. Cooling of lava is represented by a time-variable viscosity and singularities inherent in previous models for dome relaxation have been eliminated. At the onset of relaxation, bulk dynamic viscosities lie in the range between 10(exp 10) - 10(exp 16) Pa s, consistent with basaltic-andesite to rhyolitic compositions. Plausible relaxation times range from 5 to 5000 years, depending on initial lava viscosity. The first scenario, however, is only valid during the final stages of dome relaxation and does not consider the time taken for lava to be extruded onto the surface. In the second scenario, emplacement and growth of a steep-sided dome is considered when the volume of lava on the surface increases over time (i.e. time-variable volume approach). The volumetric flow rate may depend on an arbitrary power of the dome thickness, thus embracing Newtonian as well as other rheologies for describing terrestrial and planetary mass flows. The approach can be used to distinguish between basic flow rate models for fluid emplacement. The formalism results in radial expansion of a dome proportional to t(sup 1/2), consistent with the diffusive nature of the governing equation. The flow at the front is shown to thicken as the front advances for a constant rate of lava supply. Emplacement times are intimately correlated with the bulk rheology. Comparison of the theoretical profiles with the shape of a typical dome on Venus indicates that a Newtonian bulk rheology is most appropriate, consistent with prior studies. However, results here suggest a bulk dynamic viscosity

  18. Degradation of dome cutting minerals in Hanford waste

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, Jacob G.; Huber, Heinz J.; Cooke, Gary A.

    2013-01-11

    At the Hanford Tank Farms, recent changes in retrieval technology require cutting new risers in several single-shell tanks. The Hanford Tank Farm Operator is using water jet technology with abrasive silicate minerals such as garnet or olivine to cut through the concrete and rebar dome. The abrasiveness of these minerals, which become part of the high-level waste stream, may enhance the erosion of waste processing equipment. However, garnet and olivine are not thermodynamically stable in Hanford waste, slowly degrading over time. How likely these materials are to dissolve completely in the waste before the waste is processed in the Waste Treatment and Immobilization Plant can be evaluated using theoretical analysis for olivine and collected direct experimental evidence for garnet. Based on an extensive literature study, a large number of primary silicates decompose into sodalite and cancrinite when exposed to Hanford waste. Given sufficient time, the sodalite also degrades into cancrinite. Even though cancrinite has not been directly added to any Hanford tanks during process times, it is the most common silicate observed in current Hanford waste. By analogy, olivine and garnet are expected to ultimately also decompose into cancrinite. Garnet used in a concrete cutting demonstration was immersed in a simulated supernate representing the estimated composition of the liquid retrieving waste from Hanford tank 241-C-107 at both ambient and elevated temperatures. This simulant was amended with extra NaOH to determine if adding caustic would help enhance the degradation rate of garnet. The results showed that the garnet degradation rate was highest at the highest NaOH concentration and temperature. At the end of 12 weeks, however, the garnet grains were mostly intact, even when immersed in 2 molar NaOH at 80 deg C. Cancrinite was identified as the degradation product on the surface of the garnet grains. In the case of olivine, the rate of degradation in the high-pH regimes

  19. Improved manufacturing techniques for RF and laser hardening of missile domes. Phase I. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Pawlewicz, W.T.; Mann, I.B.; Martin, P.M.; Hays, D.D.; Graybeal, A.G.

    1982-07-01

    This report summarizes key results and accomplishements during the first year of a Manufacturing Methods and Technology project to adapt an existing Pacific Northwest Laboratory (PNL) optical coating capability developed for high-power fusion-laser applications to the case of rf and laser hardening of plastic missile domes used by the US Army (MICOM). The primary objective of the first year's work was to demonstrate rf hardening of Hellfire and Copperhead 1.06-micron missile domes by use of transparent conductive Indium Tin Oxide (ITO) coatings. The project thus involved adaptation of a coating material and process developed for flat glass components used in fusion lasers to the case of hemispherical or conical heat-sensitive plastic domes used on laser-guided missiles. Specific ITO coating property goals were an electrical sheet resistance of 10 Ohms/square, a coated-dome transmission of 80% or more at 1.06 micron wavelength (compared to 90% for a bare dome), and good adhesion. The sheet resistance goal of 10 Ohms/square was expected to result in an rf attenuation of 30 dB at the frequencies of importance.

  20. New radiometric ages on gneisses of the Oliverian domes in New Hampshire and Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Zartman, R.E.; Leo, G.W.

    1985-03-01

    Gneissic plutons of the Oliverian domes, mantled by Ammonoosuc Volcanics, are located along the axis of the Bronson Hill anticlinorium from New Hampshire to Connecticut. The contacts between the plutonic and volcanic rocks appear to be concordant on a regional scale, but gneiss intrudes the volcanics in several domes. Available radiometric and fossil evidence suggests that the Ammonoosuc Volcanics have a Middle Ordovician age but are somewhat older than the Oliverian gneisses. New U-Pb zircon data from Oliverian gneisses of six domes plot on a concordia diagram as an almost colinear array that yields an upper intercept age of about 444 m.y. The plotted data vary from nearly concordant to moderately discordant, the degree of discordance, correlating with /sup 207/Pb//sup 206/Pb ages that range from 459 to 415 m.y. The pattern of discordance does not relate to the uranium contents of the zircons nor to the geographic distribution of the domes. If /sup 207/Pb//sup 206/Pb ages are considered individually without an assumed consanguinity of the units, however, they do not find particular support in geologic relationships. Thus, they prefer the concordia intercept age of 444 +/- 8 m.y. for the suite as the best estimate for the time of crystallization of the Oliverian gneisses. Possibly, the Whitefield, Gneiss in the Jefferson dome represents a 10 to 15 m.y. older unit, although they are cautious about claiming such resolution with the present data.

  1. Sea-ice-related halogen enrichment at Law Dome, coastal East Antarctica

    Science.gov (United States)

    Vallelonga, Paul; Maffezzoli, Niccolo; Moy, Andrew D.; Curran, Mark A. J.; Vance, Tessa R.; Edwards, Ross; Hughes, Gwyn; Barker, Emily; Spreen, Gunnar; Saiz-Lopez, Alfonso; Corella, J. Pablo; Cuevas, Carlos A.; Spolaor, Andrea

    2017-02-01

    The Law Dome site is ideal for the evaluation of sea ice proxies due to its location near to the Antarctic coast, regular and high accumulation throughout the year, an absence of surface melting or remobilization, and minimal multiyear sea ice. We present records of bromine and iodine concentrations and their enrichment beyond seawater compositions and compare these to satellite observations of first-year sea ice area in the 90-130° E sector of the Wilkes coast. Our findings support the results of previous studies of sea ice variability from Law Dome, indicating that Wilkes coast sea ice area is currently at its lowest level since the start of the 20th century. From the Law Dome DSS1213 firn core, 26 years of monthly deposition data indicate that the period of peak bromine enrichment is during austral spring-summer, from November to February. Results from a traverse along the lee (western) side of Law Dome show low levels of sodium and bromine deposition, with the greatest fluxes in the vicinity of the Law Dome summit. Finally, multidecadal variability in iodine enrichment appears well correlated to bromine enrichment, suggesting a common source of variability that may be related to the Interdecadal Pacific Oscillation (IPO).

  2. Choroidal findings in dome-shaped macula in highly myopic eyes: a longitudinal study.

    Science.gov (United States)

    Viola, Francesco; Dell'Arti, Laura; Benatti, Eleonora; Invernizzi, Alessandro; Mapelli, Chiara; Ferrari, Fabio; Ratiglia, Roberto; Staurenghi, Giovanni; Barteselli, Giulio

    2015-01-01

    To describe choroidal findings in dome-shaped macula associated with high myopia using fluorescein angiography (FA), indocyanine green angiography (ICGA), and spectral-domain optical coherence tomography (SD OCT), and to elucidate the mechanism and natural course of serous retinal detachment (RD) associated with dome-shaped macula. Retrospective, observational case series. We reviewed longitudinal imaging results of 52 highly myopic eyes with dome-shaped macula. Changes on FA and ICGA were assessed. Retinal, choroidal, and scleral thicknesses and bulge height were measured on SD OCT. Serous RD was the most common abnormality associated with dome-shaped macula, detected by SD OCT in 44% of the cases with no associated choroidal neovascularization. Significant differences in the proportion of eyes with pinpoint leakage on FA (P macula was likely caused by choroidal vascular changes, similar to central serous chorioretinopathy, but specifically confined in the inward bulge of the staphyloma and secondary to excessive scleral thickening. Serous retinal detachment showed fluctuating changes over time, with alternating active and inactive stages. Angiographic findings in dome-shaped macula suggest the choroid as a target for possible treatment strategies. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. A low-cost method applicable worldwide for remotely mapping lava dome growth

    Science.gov (United States)

    Chaussard, Estelle

    2017-07-01

    Lava dome growth and collapse represents both a significant hazard, as it can trigger pyroclastic density currents, and a monitoring challenge, limiting monitoring to a few known active volcanoes. Here, I propose a new differencing technique based on Synthetic Aperture Radar (SAR) amplitude images to quantify the extent of lava dome growth. This differencing technique, which is both low cost and can be utilized worldwide, is applied to SAR amplitude images at Mount St. Helens and validated using 2004-2008 aerial photography observations. Difference of amplitude images accurately characterize the dome growth location. The low ground resolution of the 2004-2008 SAR data leads to underestimation by 10 to 15% of the dome extent, but the accuracy of this method will increase with the improved resolution of current and future SAR missions. Amplitude images are a low-level SAR product available from all SAR satellites, mostly freely, making the proposed method ideal for systematic, low-cost monitoring of lava dome growth worldwide with minimum processing required.

  4. Stochastic modeling of soil salinity

    NARCIS (Netherlands)

    Suweis, S.; Rinaldo, A.; Zee, van der S.E.A.T.M.; Daly, E.; Maritan, A.

    2010-01-01

    A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and

  5. Saline agriculture in Mediterranean environments

    Directory of Open Access Journals (Sweden)

    Albino Maggio

    2011-03-01

    Full Text Available Salinization is increasingly affecting world's agricultural land causing serious yield loss and soil degradation. Understanding how we could improve crop productivity in salinized environments is therefore critical to meet the challenging goal of feeding 9.3 billion people by 2050. Our comprehension of fundamental physiological mechanisms in plant salt stress adaptation has greatly advanced over the last decades. However, many of these mechanisms have been linked to salt tolerance in simplified experimental systems whereas they have been rarely functionally proven in real agricultural contexts. In-depth analyses of specific crop-salinity interactions could reveal important aspects of plant salt stress adaptation as well as novel physiological/agronomic targets to improve salinity tolerance. These include the developmental role of root vs. shoot systems respect to water-ion homeostasis, morphological vs. metabolic contributions to stress adaptation, developmental processes vs. seasonal soil salinity evolution, residual effects of saline irrigation in non-irrigated crops, critical parameters of salt tolerance in soil-less systems and controlled environments, response to multiple stresses. Finally, beneficial effects of salinization on qualitative parameters such as stress-induced accumulation of high nutritional value secondary metabolites should be considered, also. In this short review we attempted to highlight the multifaceted nature of salinity in Mediterranean agricultural systems by summarizing most experimental activity carried out at the Department of Agricultural Engineering and Agronomy of University of Naples Federico II in the last few years.

  6. A Neogene structural dome in the Klamath Mountains, California and Oregon

    Science.gov (United States)

    Mortimer, N.; Coleman, R. G.

    1985-04-01

    Regional structural doming of Neogene age has affected rocks of the Klamath and Cascade mountains near the California-Oregon border. Evidence for this is seen in (1) subannular outcrop patterns of pre-Cretaceous lithotectonic units, (2) a crude pattern of radially oriented high-angle faults, (3) tilted Jurassic plutons, (4) tilted Cretaceous to Miocene strata, and (5) various geomorphological features. The age of doming is constrained by a major middle Miocene to earliest Pliocene angular unconformity within the Cascade Mountains and uplifted upper Miocene marine beds on the western edge of the Klamath Mountains. Uplift and doming may be the result of shortening in the Cascade fore-arc region or, more speculatively, the recent accretion of subducted material to the North American plate beneath the Klamath Mountains. *Present addresses: Mortimer, Department of Geological Sciences, University of British Columbia, Vancouver, British Columbia V6T 2B4, Canada; Coleman, U.S. Geological Survey, Menlo Park, California 94025

  7. TECHNICAL NOTE: Observations on the use of a viscoelastic joint to provide noise reduced sonar domes

    Science.gov (United States)

    House, J. R.

    1997-10-01

    This paper concerns the noise and vibration advantages of an energy absorbing composite joint and its relevance to noise reduced glass reinforced polyester (GRP) sonar domes. Once installed on an operational boat, hydrodynamic flow and supporting structural induced vibrations cause the dome to vibrate, thus radiating noise and interfering with sonar sensor response. The results of a vibration transmissibility study on a GRP - steel interface are discussed as the first step in designing a composite viscoelastic joint that can act as a vibration sink to absorb flow generated and structure borne noise within GRP sonar domes. Preliminary investigations concerning the absorption of compressional waves by use of a tapered viscoelastic interlayer are discussed. It is shown that a tapered viscoelastic interlayer placed between a GRP beam and steel supporting substrate can produce a significant absorption of vibrational energy, reducing water borne radiated noise and providing a significantly quieter noise platform than conventional sonar jointing technology.

  8. [Dome-shaped macula: appearance on ultrasound and optical coherence tomography].

    Science.gov (United States)

    Chéour, M; Ben Aleya, N; Brour, J; Falfoul, Y; Agrebi, S; Skhiri, M; Kraïem, A

    2013-10-01

    The purpose of our work is to demonstrate the role of optical coherence tomography and ocular ultrasound in the diagnosis of the dome-shaped macula in high myopia. We report the case of a patient with high myopia who presented with a decrease in visual acuity and metamorphopsia in the left eye. She underwent visual acuity measurement, biomicroscopic examination and measurement of axial length. B-mode ultrasound and optical coherence tomography showed a projection of the macula in the convexity of the myopic staphyloma confirming the diagnosis of dome-shaped macula. Dome-shaped macula is a recently discovered entity, which may be responsible for a decrease in visual acuity in patients with high myopic posterior staphyloma. Ultrasound and optical coherence tomography are very helpful in making the diagnosis. Copyright © 2013. Published by Elsevier Masson SAS.

  9. Eclogite inclusions in migmatite domes as recorders of deep-crust exhumation mechanism, magnitude, and rate

    Science.gov (United States)

    Whitney, Donna; Teyssier, Christian

    2017-04-01

    Fragments of refractory material such as mafic rocks occur in quartzofeldspathic gneiss and migmatite in domal structures that form when the upper crust extends, driving rapid upward flow of the ductile lower crust. The Montagne Noire, French Massif Central, is an example of an eclogite-bearing migmatite 'double dome' characterized by a vertical high-strain zone (HSZ) and flanking subdomes. Two eclogite localities preserve garnet and omphacite: one in the HSZ and one at the SW margin of the dome. Zircon U-Pb and trace-element data for the HSZ eclogite show that high-pressure metamorphism occurred during the same orogenic event as migmatite dome formation, so the P-T-t-deformation records of eclogites in different structural sites can be used to understand deep crust exhumation in the context of dome dynamics. Numerical models predict that material in the HSZ ascends directly from the deep crust. Material in the subdomes may come from the deep crust or from more intermediate crustal levels; in some cases, dome-margin rocks follow a transport path with an earlier vertical component to the top of the dome, followed by flow into the footwall of an extensional shear zone below the shallow crust. In the Montagne Noire dome, eclogite in the HSZ contains garnet with rutile inclusion-bearing, pyrope-rich rims (up to 50 mol%) and omphacite with up to 36 mol% jadeite. Retrogression is characterized by amphibolite + plagioclase symplectite that has preferentially consumed cpx; texturally late biotite also occurs. The lower-pyrope cores of garnet contain abundant quartz inclusions and record prograde amphibolite facies metamorphism. Peak P-T conditions were 1.4 GPa at 725°C, and eclogite metamorphism was closely related to host migmatite at 315 Ma. Exhumation was rapid, from the deep crust (>40 km) to shallow emplacement of the dome at <10 km depth. Dome-margin eclogite occurs along the tectonized contact between migmatite/gneiss and the schist carapace of the dome. Garnets

  10. BENDING THE DOMING EFFECT IN STRUCTURE FROM MOTION RECONSTRUCTIONS THROUGH BUNDLE ADJUSTMENT

    Directory of Open Access Journals (Sweden)

    L. Magri

    2017-08-01

    Full Text Available Structure from Motion techniques provides low-cost and flexible methods that can be adopted in arial surveying to collect topographic data with accurate results. Nevertheless, the so-called “doming effect”, due to unfortunate acquisition conditions or unreliable modeling of radial distortion, has been recognized as a critical issue that disrupts the quality of the attained 3D reconstruction. In this paper we propose a novel method, that works effectively in the presence of a nearly flat soil, to tackle a posteriori the doming effect: an automatic ground detection method is used to capture the doming deformation flawing the reconstruction, which in turn is wrapped to the correct geometry by iteratively enforcing a planarity constraint through a Bundle Adjustment framework. Experiments on real word datasets demonstrate promising results.

  11. Nanoparticulas basadas en complejos de Fe(II) con transicion de espin: sintesis, caracterizacion y aplicaciones en electronica molecular

    Science.gov (United States)

    Monrabal Capilla, Maria

    Esta tesis doctoral esta organizada en 5 capitulos y esta destinada al estudio de sistemas de Fe (II) que presentan el fenomeno de la transicion de espin a escala nanometrica. El capitulo 1 contiene una introduccion general sobre materiales moleculares multifuncionales, destacando aquellos ejemplos mas importantes. Por otro lado, se explicara el fenomeno de la transicion de espin, tratando aspectos conceptuales, los antecedentes mas importantes y la situacion actual. En el capitulo 2 se describen los diferentes procesos existentes para la obtencion de diferentes tipos de nanoparticulas. Ademas, se presenta la sintesis y caracterizacion de nanoparticulas del polimero de coordinacion unidimensional [Fe(Htrz)2(trz)]BF4, obtenidas mediante el metodo de micelas inversas. Estas nanoparticulas, con una estrecha distribucion de tamanos centrada alrededor de los 11 nm, presentan una transicion de espin muy abrupta, con un ancho ciclo de histeresis termica de unos 40K. En el capitulo 3 se describe el proceso de modificacion del tamano de las nanoparticulas descritas en el capitulo anterior, llevado a cabo variando la proporcion de surfactante/H2O en el medio. Ademas, con el objetivo de modificar las propiedades magneticas de las nanoparticulas obtenidas en el capitulo 2, se lleva a cabo la sintesis de nanoparticulas de polimeros de la misma familia del [Fe(Htrz)2(trz)]BF4. En concreto se sintetizaron 3 nuevos tipos de nanoparticulas basadas en el polimero [Fe(Htrz)1-x(NH2trz)x](ClO4)2, siendo x = 0.05, 0.15 y 0.3, en cada caso. Estas nanoparticulas siguen presentando una estrecha distribucion de tamanos y una transicion de espin muy abrupta y con un ancho ciclo de histeresis. Ademas, se observa que este ciclo se desplaza a temperaturas mas proximas a la temperatura ambiente a medida que se aumenta el porcentaje de 4-amino-1, 2, 4- triazol en la muestra. Pero al mismo tiempo se produce una disminucion de la anchura de este ciclo. Por ultimo, en este capitulo se presenta la

  12. Characterization of OT4-1 Alloy by Multi-Dome Forming Test.

    Science.gov (United States)

    Zakhariev, Ivan; Aksenov, Sergey; Kotov, Anton; Kolesnikov, Aleksey

    2017-08-03

    In this study, the rheological characteristics of a titanium alloy have been obtained by multi-dome bulging test. Free bulging process is an experimental technique that can be used to characterize material in conditions of biaxial tension during superplastic, as well as conventional, hot forming. The constitutive constants are calculated on a base of the information about the bulge geometry, applied pressure, and forming time. A multi-dome forming test allows one to reduce the number of the experiments required for the characterization, since every multi-dome test produces several domes of different size. In this study, a specific die for multi-dome test was used. The die has six holes with different radiuses of 20, 25, 30, 35, 40, and 45 mm. During a test, the specimen is clamped between blank holder and die holder, heated to a specific temperature, and formed by applying constant gas pressure. The experiments were conducted at different temperatures for OT4-1 titanium alloy. The constitutive constants were obtained by processing the experimental data using two different techniques and compared with tensile test results. In order to estimate the influence of friction on the experimental results and to verify obtained material characteristics, finite element (FE) simulation was performed. Finally, the results of FE simulation were compared with the experimental data. The results of the simulation show the advantage of material characterization based on multi dome tests and its interpretation by inverse analysis. The deviations produced by the effect of friction are more significant when the direct approach is applied instead of inverse analysis with a semi analytical model of the bulging process.

  13. Characterization of OT4-1 Alloy by Multi-Dome Forming Test

    Directory of Open Access Journals (Sweden)

    Ivan Zakhariev

    2017-08-01

    Full Text Available In this study, the rheological characteristics of a titanium alloy have been obtained by multi-dome bulging test. Free bulging process is an experimental technique that can be used to characterize material in conditions of biaxial tension during superplastic, as well as conventional, hot forming. The constitutive constants are calculated on a base of the information about the bulge geometry, applied pressure, and forming time. A multi-dome forming test allows one to reduce the number of the experiments required for the characterization, since every multi-dome test produces several domes of different size. In this study, a specific die for multi-dome test was used. The die has six holes with different radiuses of 20, 25, 30, 35, 40, and 45 mm. During a test, the specimen is clamped between blank holder and die holder, heated to a specific temperature, and formed by applying constant gas pressure. The experiments were conducted at different temperatures for OT4-1 titanium alloy. The constitutive constants were obtained by processing the experimental data using two different techniques and compared with tensile test results. In order to estimate the influence of friction on the experimental results and to verify obtained material characteristics, finite element (FE simulation was performed. Finally, the results of FE simulation were compared with the experimental data. The results of the simulation show the advantage of material characterization based on multi dome tests and its interpretation by inverse analysis. The deviations produced by the effect of friction are more significant when the direct approach is applied instead of inverse analysis with a semi analytical model of the bulging process.

  14. Location of a new ice core site at Talos Dome (East Antarctica

    Directory of Open Access Journals (Sweden)

    I. Tabacco

    2006-06-01

    Full Text Available In the frame of glaciology and palaeoclimate research, Talos Dome (72°48lS; 159°06lE, an ice dome on the East Antarctic plateau, represents the new selected site for a new deep ice core drilling. The increasing interest in this region is due to the fact that the ice accumulation is higher here than in other domes in East Antarctica. A new deep drilling in this site could give important information about the climate changes near the coast. Previous papers showed that the dome summit is situated above a sloped bedrock. A new position on a relatively flat bedrock 5-6 km far from here in the SE direction was defined as a possible new ice core site for an European (Italy, France, Swiss and United Kingdom drilling project named as TALDICE (TALos Dome Ice Core Project. This point, named as ID1 (159°11l00mE; 72°49l40mS, became the centre of the Radio Echo Sounding (RES flight plan during the 2003 Italian Antarctic expedition, with the aim of confirming the new drilling site choice. In this paper 2001 and 2003 RES data sets have been used to draw a better resolution of ice thickness, bottom morphology and internal layering of a restricted area around the dome. Based on the final results, point ID1 has been confirmed as the new coring site. Finally, the preliminary operations about the installation of the summer ice core camp (TALDICE at ID1 site carried out during the XX Italian Antarctic expedition (November 2004-December 2005 are briefly described.

  15. Geochemical constraints on the genesis of the Scheelite dome intrusion-related gold deposit, Tombstone gold belt, Yukon, Canada

    Science.gov (United States)

    Mair, J.L.; Goldfarb, R.J.; Johnson, C.A.; Hart, C.J.R.; Marsh, E.E.

    2006-01-01

    The Scheelite dome intrusion-related gold deposit, western Selwyn basin, Yukon, is hosted in hornfelsed metasedimentary strata that lie adjacent to the exposed apices of a monzogranite to quartz monzonite plutonic complex of the mid-Cretaceous Tombstone-Tungsten magmatic belt, Tintina gold province, Alaska and Yukon. A variety of mineralization styles occur throughout a 10- ?? 3-km east-trending corridor and include reduced Au- and W-rich skarns, Au, W- and Ag-Pb-Zn-Sb-rich quartz tension-vein arrays, and multiphase fault veins and isolated zones of Au-rich sericite-carbonate altered rock. Integrated U-Pb SHRIMP data for magmatic zircon and Ar-Ar data for magmatic and hydrotbermal biotite indicate that gold mineralization occurred within 1 to 2 m.y. of magma emplacement. Fluid inclusion, oxygen isotope, and arsenopyrite geothermometry data indicate that hydrothermal minerals formed at depths of 6 to 9 km over a temperature range from 550??C. High-temperature Au-rich skarns formed at >400??C, whereas vein-hosted mineralization formed at 280?? to 380??C. In skarns, Au is strongly associated with enrichments of Bi, Te, W, and As, whereas a variety of Au-rich veins occur, with Asrich (type 1), and Te- and W-rich (type 2) end members. Silver-Pb-Zn-Sb veins are typically Au poor and represent the latest and lowest temperature phase in the hydrothermal paragenesis. The fluid inclusion data indicate that all mineralization styles were formed from low-salinity (???4 wt % NaCl equiv) aqueous-carbonic fluids, consistent with the composition of fluid inclusions within infilled miarolitic cavities in the intrusive rocks. However, the nonaqueous fluid was predominantly CH4 in skarn, CO2 in Au-Te and Au-W veins, and a fluid with roughly equal amounts Of CO2, CH4, and N2 in Au-As and Ag-Pb-Zn-Sb veins. Oxygen isotope data are consistent with a mineralizing fluid of predominantly magmatic origin that was variably modified to more positive ??18O values during interaction with 18O

  16. Stochastic Modeling of Soil Salinity

    Science.gov (United States)

    Suweis, Samir; Rinaldo, Andrea; van der Zee, Sjoerd E. A. T. M.; Maritan, Amos; Porporato, Amilcare

    2010-05-01

    Large areas of cultivated land worldwide are affected by soil salinity. Estimates report that 10% of arable land in over 100 countries, and nine million km2 are salt affected, especially in arid and semi-arid regions. High salinity causes both ion specific and osmotic stress effects, with important consequences for plant production and quality. Salt accumulation in the root zone may be due to natural factors (primary salinization) or due to irrigation (secondary salinization). Simple (e.g., vertically averaged over the soil depth) coupled soil moisture and salt balance equations have been used in the past. Despite their approximations, these models have the advantage of parsimony, thus allowing a direct analysis of the interplay of the main processes. They also provide the ideal starting point to include external, random hydro-climatic fluctuations in the analysis of long-term salinization trends. We propose a minimalist stochastic model of primary soil salinity, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equation to a stochastic differential equation driven by multiplicative Poisson noise. The novel analytical solutions provide insight on the interplay of the main soil, plant and climate parameters responsible for long-term soil salinization. In fact, soil salinity statistics are obtained as a function of climate, soil and vegetation parameters. These, in turn, can be combined with soil moisture statistics to obtain a full characterization of soil salt concentrations and the ensuing risk of primary salinization. In particular, the solutions show the existence of two quite distinct regimes, the first one where the mean salt mass remains nearly constant with increasing rainfall frequency, and the

  17. Transthoracic percutaneous radiofrequency ablation for liver tumors in the hepatic dome.

    Science.gov (United States)

    Shibata, Toyomichi; Shibata, Toshiya; Maetani, Yoji; Kubo, Takeshi; Itoh, Kyo; Togashi, Kaori; Hiraoka, Masahiro

    2004-11-01

    Computed tomography (CT)-guided transthoracic radiofrequency ablation was performed for nine liver tumors of eight patients, which were located in the hepatic dome and undetectable by ultrasound (US). A total 11 sessions of ablation were performed. Complications were noted in five sessions (45%) and no complications were noted in six sessions (55%). Pneumothorax was noted in five sessions (45%), including two sessions (18%) with major pneumothorax requiring a chest tube. Major complications were seen in two sessions (18%), major pneumothorax and both major pneumothorax and moderate pleural effusion, respectively. CT-guided transthoracic radiofrequency ablation may be an alternative for treatments of liver tumor in the hepatic dome.

  18. Serous retinal detachment accompanied by MEWDS in a myopic patient with dome-shaped macula.

    Science.gov (United States)

    Shin, Min Kyu; Byon, Ik Soo; Park, Sung Who; Lee, Ji Eun

    2014-01-01

    Macular serous retinal detachment (MSRD) is a rare complication in highly myopic patients with an inferior staphyloma, tilted disc, or dome-shaped macula. Multiple evanescent white dot syndrome (MEWDS) presents with sudden visual loss and multiple yellowish dots that resolve spontaneously within several weeks. The authors report the development and spontaneous resolution of subretinal fluid accompanied by MEWDS in a myopic patient with a dome-shaped macula. Dysfunction of the retinal pigment epithelium due to MEWDS likely induced temporary MSRD in this patient. Copyright 2014, SLACK Incorporated.

  19. ASTEP: Towards the detection and characterization of exoplanets from Dome C

    Directory of Open Access Journals (Sweden)

    Rauer H.

    2011-02-01

    Full Text Available The ASTEP project (Antarctic Search for Transiting ExoPlanets, aims at testing the quality of the Dome C site in Antarctica for photometry in the visible, as well as detecting and characterizing transiting exoplanets. A dedicated telescope, ASTEP400, has been developped and installed at Concordia. The first campaign took place during the winter 2010, and the telescope functionned nominally during all the winter. A first analysis of the data leads to a precision of 189 and 205 ppm for WASP-19 and WASP-18 respectively, for continuous observations during 1 month. This shows that extremely high precision photometry is achievable from Dome C.

  20. High salinity wastewater treatment.

    Science.gov (United States)

    Linarić, M; Markić, M; Sipos, L

    2013-01-01

    The shock effect, survival and ability of activated sludge to acclimatize to wastewater containing different concentrations of NaCl and Na2SO4 were investigated under laboratory conditions. To accomplish this, the potential penetration of a sewage system by seawater as a consequence of storm surge flooding was simulated. The experiments were conducted using activated sludge taken from the aeration tank of a communal wastewater treatment plant and adding different concentrations up to 40 g/L of NaCl and 4.33 g/L of Na2SO4. The effects of salinity on the activated sludge were monitored for 5 weeks based on the values of pH, dissolved oxygen, total suspended solids, volatile suspended solids, sludge volume, sludge volume index, electrokinetic potential, respirometric measurements and enzymatic activity. The addition of salt sharply reduced or completely inhibited the microbial activity in activated sludge. When salt concentrations were below 10 g/L NaCl, microorganisms were able to acclimatize in several weeks and achieve the same initial activity as in raw sludge samples. When the salt concentration was above 30 g/L NaCl, the acclimatization process was very slow or impossible.

  1. Crowning the Cathedral of Florence: Brunelleschi Builds His Dome. A Unit of Study for Grades 7-10.

    Science.gov (United States)

    Symcox, Linda

    This unit focuses on a dramatic moment in the Renaissance from about 1420 when Filippo Brunelleschi single handedly created, defined, and engineered a new architecture by building the great dome of the cathedral of Santa Maria del Fiore in Florence. The dome became the symbol of Florence's grandeur during the Renaissance, and a model for great…

  2. NOAA Average Annual Salinity (3-Zone)

    Data.gov (United States)

    California Department of Resources — The 3-Zone Average Annual Salinity Digital Geography is a digital spatial framework developed using geographic information system (GIS) technology. These salinity...

  3. Interactive effects of incubation temperature and salinity on the early life stages of pacific cod Gadus macrocephalus

    Science.gov (United States)

    Bian, Xiaodong; Zhang, Xiumei; Sakurai, Yasunari; Jin, Xianshi; Wan, Ruijing; Gao, Tianxiang; Yamamoto, Jun

    2016-02-01

    The combined effects of incubation temperature and salinity on the early life stages of Pacific cod Gadus macrocephalus were examined under controlled laboratory conditions. Data were collected from two synchronized experiments. Experiment 1 was designed to evaluate the interactive effects of incubation temperature and salinity on the hatchability of fertilized G. macrocephalus eggs. Experiment 2 was set up to evaluate the interactive effects of incubation temperature and salinity on the time from hatching to 50% mortality of the non-fed yolk-sac larvae (M50). The results show that temperature could significantly influence the development and hatchability of the larvae, as well as the hatching characteristics of G. macrocephalus. Viable hatch was significantly influenced by salinity when the upper and lower thermal limits were approached and shows the synergism of low salinity on egg development at low-temperatures and conversely inhibitory effects of low-salinity at high-temperatures. Data on developmental rates as influenced by temperature were presented at each tested salinity level. No influence of salinity was found at the temperature levels tested. Dome-shaped quadratic curves were fitted to the relationship between temperature and the incidence of larval size and yolk storage at hatch for most of the tested salinity levels. The effect of salinity across all temperatures, however, had a much smaller influence on larval size and no effect on yolk storage at hatch. The influence of temperature on larval duration (time from hatching to M50) could be described in all cases by an exponential power function. Evidence on the synergism of low salinity at low-temperatures and conversely inhibitory effects of low-salinity at high-temperatures was also observed. The results were discussed in reference to salinity modified temperature effects on the early life stages of G. macrocephalus. Maximum hatchability and larval size at hatch, and moderate salinity tolerance and

  4. World Ocean Atlas 2005, Salinity

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Ocean Atlas 2005 (WOA05) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen...

  5. Optical sensor for seawater salinity.

    Science.gov (United States)

    Huber, C; Klimant, I; Krause, C; Werner, T; Mayr, T; Wolfbeis, O S

    2000-01-01

    An optical sensor for the measurement of salinity in seawater has been developed. It is based on a chloride-quenchable fluorescent probe (lucigenin) immobilized on a Nafion film. Two approaches for measuring salinity via chloride concentration are presented. In the first, a change in salinity corresponds to a change in the fluorescence intensity of lucigenin. In the second, the fluorescence intensity information is converted into a phase angle information by adding an inert phosphorescent reference luminophore (a ruthenium complex entrapped in poly(acrylonitrile) beads). Under these conditions, the chloride-dependent fluorescence intensity of lucigenin can be converted into a chloride-dependent fluorescence phase shift which serves as the analytical information. This scheme is referred to as dual lifetime referencing (DLR). The sensor was used to determine the salinity in seawater and brackish water of the North Sea.

  6. Stochastic Modeling of Soil Salinity

    CERN Document Server

    Suweis, S; Van der Zee, S E A T M; Daly, E; Maritan, A; Porporato, A; 10.1029/2010GL042495

    2012-01-01

    A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equation to a single stochastic differential equation driven by multiplicative Poisson noise. The novel analytical solutions provide insight on the interplay of the main soil, plant and climate parameters responsible for long-term soil salinization. In particular, they show the existence of two distinct regimes, one where the mean salt mass remains nearly constant (or decreases) with increasing rainfall frequency, and another where mean salt content increases markedly with increasing rainfall frequency. As a result, relatively small reductions of rainfall in drier climates may entail dramatic shifts in long-term soil salinization trend...

  7. NOAA NOS SOS, EXPERIMENTAL - Salinity

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA NOS SOS server is part of the IOOS DIF SOS Project. The stations in this dataset have salinity data. *These services are for testing and evaluation use...

  8. Simulated Service and Stress Corrosion Cracking Testing for Friction Stir Welded Spun Formed Domes

    Science.gov (United States)

    Stewart, Thomas J.; Torres, Pablo D.; Caratus, Andrei A.; Curreri, Peter A.

    2010-01-01

    Simulated service testing (SST) development was required to help qualify a new 2195 aluminum lithium (Al-Li) alloy spin forming dome fabrication process for the National Aeronautics and Space Administration (NASA) Exploration Development Technology Program. The application for the technology is to produce high strength low weight tank components for NASA s next generation launch vehicles. Since plate material is not currently manufactured large enough to fabricate these domes, two plates are joined by means of friction stir welding. The plates are then pre-contour machined to near final thicknesses allowing for a thicker weld land and anticipating the level of stretch induced by the spin forming process. The welded plates are then placed in a spin forming tool and hot stretched using a trace method producing incremental contours. Finally the dome receives a room temperature contour stretch to final dimensions, heat treatment, quenching, and artificial aging to emulate a T-8 condition of temper. Stress corrosion cracking (SCC) tests were also performed by alternate immersion in a sodium chloride (NaCl) solution using the typical double beam assembly and with 4-point loaded specimens and use of bent-beam stress-corrosion test specimens under alternate immersion conditions. In addition, experiments were conducted to determine the threshold stress intensity factor for SCC (K(sub ISCC)) which to our knowledge has not been determined previously for Al-Li 2195 alloy. The successful simulated service and stress corrosion testing helped to provide confidence to continue to Ares 1 scale dome fabrication

  9. Development, characteristics and comparative structural analysis of tensegrity type cable domes

    Directory of Open Access Journals (Sweden)

    Nenadović Aleksandra

    2010-01-01

    Full Text Available Tensegrity type cable domes are three-dimensional structural configurations, prestressed inside the perimeter compression ring, in which the continuous tension throughout the roof structure is made by continuous tension cables and discontinuous compression struts. These kinds of structures can be formed like spatially triangulated networks or like networks nontriangulated in space. This paper examines some effects of network geometry on the behaviour and structural efficiency of tensegrity type cable domes. In this paper the roof cover is considered non-interactive with the supporting structure, unlike rigidly clad tensegrity type cable domes. Since the main bearing elements of tensegrity type cable domes are prestressed cables, they show non-linear load deformation and rely upon geometric stiffness. A geometrically non-linear analysis of non-triangulated and triangulated structures for different load conditions was conducted employing a computer program based on the perturbation theory. The incrementally-iterative procedure, with an approximation of the stiffness matrix by combining the elastic and geometric stiffness matrix, allows detection of structural instabilities.

  10. Barnes Ice Cap South Dome Trilateration Net Survey Data 1970-1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Barnes Ice Cap data set contains survey measurements of a network of 43 stakes along a 10 km flow line on the northeast flank of the south dome of the Barnes Ice...

  11. Re-assessment of recent (2008–2013 surface mass balance over Dome Argus, Antarctica

    Directory of Open Access Journals (Sweden)

    Minghu Ding

    2016-04-01

    Full Text Available At Dome Argus, East Antarctica, the surface mass balance (SMB from 2008 to 2013 was evaluated using 49 stakes installed across a 30×30 km area. Spatial analysis showed that at least 12 and 20 stakes are needed to obtain reliable estimates of SMB at local scales (a few hundred square metres and regional scales (tens of square kilometres, respectively. The estimated annual mean SMB was 22.9±5.9 kg m−2 yr−1, including a net loss by sublimation of −2.22±0.02 kg m−2 yr−1 and a mass gain by deposition of 1.37±0.01 kg m−2 yr−1. Therefore, ca. 14.3% of precipitation was modified after deposition, which should be considered when interpreting snow or ice core records produced by future drilling projects. The surface snow density and SMB in the western portion of Dome Argus are higher than in other areas, and these differences are likely related to the katabatic wind, which is strengthened by topography in this sector. A new digital elevation model (DEM of Dome Argus was generated, confirming that both peaks of the dome can be considered as the summit of the East Antarctic Ice Sheet. Findings from this study should be valuable for validating SMB estimates obtained from regional climate models and DEMs established using remote-sensing data.

  12. Serous Retinal Detachment in Dome-shaped Macula with 7 Years Follow-up.

    Science.gov (United States)

    Alakeely, Adel G; Alrashaed, Saba

    2016-01-01

    Dome-shaped macula (DSM) was first described by Gaucher et al. as a convex protrusion of macula within a staphyloma in highly myopic eyes that cause visual impairment associated with serous foveal detachment (SFD). We describe a patient with persistent SFD in DSM documented by serial spectral domain optical coherence tomography for 7 years with stable vision.

  13. Mud volcanos and mud domes of the central Mediterranean Ridge: near bottom and in situ observations

    NARCIS (Netherlands)

    Huguen, C.; Mascle, J.; Woodside, J.M.; Zitter, T.A.C.; Foucher, J.-P.

    2005-01-01

    The first high-resolution mapping of mud volcanoes and mud domes of the Central Mediterranean Ridge (Eastern Mediterranean) presented here is based on successive in situ observations from the Nautile submersible [MEDINAUT (1998) and NAUTINIL (2003) surveys] and near-bottom side-scan sonar data

  14. Fusée ceramic vaults and domes in the Netherlands

    NARCIS (Netherlands)

    Kamerling, M.W.

    2011-01-01

    This paper gives an overview of the fusée Ceramique vaults and domes constructed in The Netherlands just after World War II and describes the technique of construction as well as the advantages and disadvantages. Using only a minimum of concrete and steel, the environmental load of the vaults is

  15. Methyl Bromide Measurements in the Taylor Dome M3C1 Ice Core, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — The data set includes methyl bromide (CH3Br) measurements made on air extracted from 70 samples from the Taylor Dome M3C1 ice core. CH3Br was measured in air from...

  16. Fish oil curtails the human action potential dome in a heterogeneous manner: Implication for arrhythmogenesis

    NARCIS (Netherlands)

    Verkerk, Arie O.; den Ruijter, Hester M.; de Jonge, Nicolaas; Coronel, Ruben

    2009-01-01

    Omega-3 polyunsaturated fatty acids (omega3-PUFAs) from fish oil modulate various ion channels, including the L-type calcium current (I(Ca,L)). As a result, fish oil shortens the cardiac action potential and may cause a loss of the dome of the action potential (AP). Under conditions of increased

  17. Enduring perceptions: Place naming and the perception of Louisiana’s salt dome islands

    Directory of Open Access Journals (Sweden)

    Philip Hayward

    2016-11-01

    Full Text Available Salt domes are geological features that occur when areas of salt deposits are pressured into layers above them, causing dome shaped distortions in horizontal strata. In some instances, the distortions protrude above flat areas of land or else appear underwater as seamounts. In the case of the five Louisiana salt dome hills considered in this article, their distinct elevation above the swampy bayous and flatlands surrounding them has led to their characterisation as islands by indigenous Atakapa-Ishak peoples and by subsequent Francophone and Anglophone settlers. The article considers the ways in which the five salt domes’ islandness has been perceived, enhanced and/or undermined by various local inhabitants and/or the commercial operations that have operated on them. Discussion of these aspects involves consideration of the manner in which the salt dome islands’ islandness is mutable and complex, particularly with regard to human impacts. This mutability is discussed with regard to both individual island placenames and the islands’ overall designations.

  18. Eagle Oil and Gas Company – Sheldon Dome Field NPDES Permit

    Science.gov (United States)

    Under NPDES permit WY-0020338, the Eagle Oil and Gas Company is authorized to discharge from its Sheldon Dome Field wastewater treatment facility in Fremont County, Wyoming, to an unnamed ephemeral tributary of Dry Creek, a tributary to the Wind River.

  19. Airborne L-band radiometer mapping of the dome-C area in Antarctica

    DEFF Research Database (Denmark)

    Skou, Niels; Kristensen, Steen Savstrup; Søbjærg, Sten Schmidl

    2015-01-01

    A 350 km × 350 km area near the Concordia station on the high plateau of Dome-C in Antarctica has been mapped by an airborne L-band radiometer system. The area was expected to display a rather uniform brightness temperature (TB) close to the yearly mean temperature-well suited for calibration...

  20. Mapping of the DOME-C area in Antarctica by an airborne L-band radiometer

    DEFF Research Database (Denmark)

    Skou, Niels; Kristensen, Steen Savstrup; Søbjærg, Sten Schmidl

    2014-01-01

    A 350 × 350 km area near the Concordia station on the high plateau of Dome C in Antarctica has been mapped by an airborne L-band radiometer system. The area was expected to display a rather uniform brightness temperature close to the yearly mean temperature — well suited for calibration checks...

  1. The eastern Central Pamir Gneiss Domes: temporal and spatial geometry of burial and exhumation

    Science.gov (United States)

    Rutte, Daniel; Stearns, Michael; Ratschbacher, Lothar

    2013-04-01

    We present a structural and thermochronologic study of the Gneiss Domes and their cover in the Central Pamir. Emphasis is laid on presentation and discussion of new 40Ar-39Ar dates embedded in two structural profiles through the central Muskol and western Shatput domes. The structure of the Central Pamir is dominated by Cenozoic deformation related to the India-Asia collision. Only few structures of the Phanerozoic amalgamation of the Pamir were not reactivated. The Cenozoic structural development of the Central Pamir can be simplified into three phases: 1) Between initial collision of India and Asia to 28-20 Ma (peak metamorphism, U-Pb monazite) the emplacement of large thrust sheets led to strong north-south shortening;" in the eastern Central Pamir the major thrust sheet has a minimum displacement of 35 km. The stratigraphic thickness of this nappe is ~7 km but its internal structure and thus its true thickness is weakly constrained by the available data. Klippen of Early Paleozoic strata of this thrust sheet south of the Central Pamir Muskol and Shatput domes cover Carboniferous to Triassic strata of the footwall; they can be linked to the Akbaital nappe previously mapped by Russian geologists north of the domes. In the Sasaksu valley of the Muskol dome, the thrust sheet is intruded by a ~36 Ma granodiorite (new U-Pb zircon dates). (2) This crustal imbricate stack is cut by east-trending normal faults and shear zones that define the Central Pamir Gneiss Domes. Normal shear is concentrated along the northern margin of the domes and was the main process associated with exhumation of the domes from ~30 km depth at 20-15 Ma (U-Th/Pb titanite and monazite, Ar-Ar, fission-track geo-thermochronology). One granite at ~35 Ma (U-Pb zircon) pre-dates exhumation while three leucocratic dykes (18-20 Ma U-Pb monazite and zircon) are dated to be coeval with the initial stages of exhumation. Detrital U-Pb zircon ages of the high-grade metasediments indicate that the protoliths

  2. The PLATO Dome A site-testing observatory: Power generation and control systems

    Science.gov (United States)

    Lawrence, J. S.; Ashley, M. C. B.; Hengst, S.; Luong-van, D. M.; Storey, J. W. V.; Yang, H.; Zhou, X.; Zhu, Z.

    2009-06-01

    The atmospheric conditions above Dome A, a currently unmanned location at the highest point on the Antarctic plateau, are uniquely suited to astronomy. For certain types of astronomy Dome A is likely to be the best location on the planet, and this has motivated the development of the Plateau Observatory (PLATO). PLATO was deployed to Dome A in early 2008. It houses a suite of purpose-built site-testing instruments designed to quantify the benefits of Dome A site for astronomy, and science instruments designed to take advantage of the observing conditions. The PLATO power generation and control system is designed to provide continuous power and heat, and a high-reliability command and communications platform for these instruments. PLATO has run and collected data throughout the winter 2008 season completely unattended. Here we present a detailed description of the power generation, power control, thermal management, instrument interface, and communications systems for PLATO, and an overview of the system performance for 2008.

  3. Colorectal carcinoma with dome-like phenotype: an under-recognised subset of colorectal carcinoma?

    DEFF Research Database (Denmark)

    Asmussen, L; Pachler, J; Holck, S

    2008-01-01

    The term dome carcinoma has been applied to a variant of colorectal carcinoma, thought to derive from M-cells of the gut-associated lymphoid tissue. Its distinguishing morphological features include a non-polypoid plaque-like lesion composed of closely apposed cystically dilated glands lined...

  4. Alternative co-digestion scenarios for efficient fixed-dome reactor biomethanation processes

    DEFF Research Database (Denmark)

    Fotidis, Ioannis; Laranjeiro, Tiago; Angelidaki, Irini

    2016-01-01

    VS ratio, respectively. Three fixed-dome reactors, R30, R45 and R60, fed with all substrates, operated with hydraulic retention times of 30, 45, and 60 days and organic loading rates of 2.18, 1.46, and 1.09 g VS L−1 d−1, respectively (different co-digestion scenarios). R60 was the best continuous co...

  5. The sedimentary and structural history of the Valsurvio Dome Cantabrian Mountains, Spain

    NARCIS (Netherlands)

    Koopmans, B.N.

    1961-01-01

    A continuous sequence of about 1000 m of Devonian sediments has been found in the Valsurvio dome, ranging from probable Siegenian to Famennian in age. This sequence of a neritic-littoral facies shows similar characteristics to the Devonian found further west in the province of León. North of the

  6. Recent Progress on Cross-Comparison of Terra and Aqua MODIS Calibration Using Dome C

    Science.gov (United States)

    Xiong, X.; Wu, A.; Angal, A.; Wenny, B.

    2009-01-01

    For the past few years, the MODIS Characterization Support Team (MCST) at NASA/GSFC has continued to evaluate the Terra and Aqua MODIS calibration long-term stability and their calibration consistency using sensor observations over the Dome Concordia, Antarctica. Early results from Dome C observations show that the calibration of bands I and 2 (0.65 and 0.86 micron) is consistent within 1-2% and bands 31 and 32 (11 and 12 micron) differences are less than a couple of tenths of Kelvin, demonstrating that this site can provide a useful calibration reference for a wide range of Earth-observing sensors from visible (VIS) to long-wave infrared (LWIR). Recently, the Dome C area has been endorsed by the CEOS as a reference standard site for sensor cross-comparison. This, as a result, has led to an invitation to the broad community to participate in a CEOS comparison of top-of-atmosphere (TOA) spectral radiance/reflectance over Dome C. In this paper, we provide a brief description of the methodologies and report our recent progress on cross-comparison of Terra and Aqua MODIS spectral bands using observations over this area, including data provided in support of the upcoming CEOS comparison. Emphasis of this paper is on the long-term data records of MODIS instruments, their calibration consistency, and challenging issues.

  7. fracture of the dome of the talus associated with a fracture of the os ...

    African Journals Online (AJOL)

    1971-03-13

    Mar 13, 1971 ... Falls from a height are commonly associated with fractures of the os calcis, the distal tibia and fibula, the acetabulum, the thoracic and lumbar spine and the base of the skull. An association between a fracture of the dome of the talus on one side and a fracture of the os calcis on the other is very unusual.

  8. The PLATO Dome A site-testing observatory: power generation and control systems.

    Science.gov (United States)

    Lawrence, J S; Ashley, M C B; Hengst, S; Luong-Van, D M; Storey, J W V; Yang, H; Zhou, X; Zhu, Z

    2009-06-01

    The atmospheric conditions above Dome A, a currently unmanned location at the highest point on the Antarctic plateau, are uniquely suited to astronomy. For certain types of astronomy Dome A is likely to be the best location on the planet, and this has motivated the development of the Plateau Observatory (PLATO). PLATO was deployed to Dome A in early 2008. It houses a suite of purpose-built site-testing instruments designed to quantify the benefits of Dome A site for astronomy, and science instruments designed to take advantage of the observing conditions. The PLATO power generation and control system is designed to provide continuous power and heat, and a high-reliability command and communications platform for these instruments. PLATO has run and collected data throughout the winter 2008 season completely unattended. Here we present a detailed description of the power generation, power control, thermal management, instrument interface, and communications systems for PLATO, and an overview of the system performance for 2008.

  9. Saline waters and soil quality

    Directory of Open Access Journals (Sweden)

    Carmelo Dazzi

    Full Text Available The processes of secondary salinization due to anthropic actions are considered one of the most important environmental emergencies owing to their level of dangerousness. The soils of the dry areas of the Mediterranean basin are particularly prone to these processes. In such environments, it is imperative to resort to irrigation that allow for the reduction of risks due to soil moisture deficit and for the stabilization of yields. Frequently, saline waters are used that cause a lowering of the soil quality. If on one hand the presence of salts can benefit the soils mainly improving soil structure, on the other high levels of salts produce negative effects on soils and crops.When sodium prevails problems of soil quality can rise such as structure degradation, low hydraulic conductivity, soil sealing. The processes of secondary soil salinization due to the use of saline waters for irrigation are particularly evident in our Country among others. In Italy, saline soils are mainly distributed in long strips of the coastal belt of the Tyrrhenian sea and Adriatic sea, in the coastal belt of Apulia, Basilicata and Sardinia and in wide areas of Sicily. It is not possible to suggest general actions to combat soil salinization because we must take into consideration that in the relationship soil-water two different quality concept interact: one linked to the soils, the other to the waters.

  10. Saline waters and soil quality

    Directory of Open Access Journals (Sweden)

    Carmelo Dazzi

    2011-02-01

    Full Text Available The processes of secondary salinization due to anthropic actions are considered one of the most important environmental emergencies owing to their level of dangerousness. The soils of the dry areas of the Mediterranean basin are particularly prone to these processes. In such environments, it is imperative to resort to irrigation that allow for the reduction of risks due to soil moisture deficit and for the stabilization of yields. Frequently, saline waters are used that cause a lowering of the soil quality. If on one hand the presence of salts can benefit the soils mainly improving soil structure, on the other high levels of salts produce negative effects on soils and crops.When sodium prevails problems of soil quality can rise such as structure degradation, low hydraulic conductivity, soil sealing. The processes of secondary soil salinization due to the use of saline waters for irrigation are particularly evident in our Country among others. In Italy, saline soils are mainly distributed in long strips of the coastal belt of the Tyrrhenian sea and Adriatic sea, in the coastal belt of Apulia, Basilicata and Sardinia and in wide areas of Sicily. It is not possible to suggest general actions to combat soil salinization because we must take into consideration that in the relationship soil-water two different quality concept interact: one linked to the soils, the other to the waters.

  11. Assessment of the Extent of Land Deformation Associated with Salt Domes within the Jazan City and Surroundings, Saudi Arabia

    Science.gov (United States)

    Pankratz, H. G.; Sultan, M.; Fathy, K.; AlMogren, S. M.; Harbi, H.; Sefry, S.; Emil, M.; Elkadiri, R.; Ahmed, M.; Othman, A.; Chouinard, K.

    2016-12-01

    The Jazan city in the Jazan Province of the Kingdom of Saudi Arabia is a vibrant and rapidly growing economic center and port. The old city of Jazan is centered over a salt dome (diaper) that crops out over an area, 3-4 km wide and 20 to 40 m above surroundings. The intrusion of the diaper into the overlying cap rock causes uneven surfaces, compromises building foundations, and causes infrastructural problems. Our study is aimed at the assessment of the salt dome-related land deformation. Using observations acquired over known locations of salt domes in Jazan and neighboring Farsan Islands, we identified criteria by which previously unidentified, near-surface salt domes, could be mapped. The selected criteria and/or applied methodologies included: (1) deformation over potential salt dome locations detected from Envisat, ERS-2, and Sentinel-1 scenes using the Stanford Method for Persistent Scatterers [StaMPs] and SARscape software. Uplift rates of about 3 mm/yr were observed over the salt dome outcrop in Jazan with increasing rates towards the center, indicating continuous rise of the salt diaper. (2) Local elevation highs over potential, near surface, salt dome intrusions observed in high spatial resolution (12.5 m), PALSAR digital elevation model (DEM). The elevation the Jazan dome is 45m high, whereas its surroundings are 15-30m high. (3) Negative Bouguer gravity anomalies over potential salt dome locations (Bouguer maps generated from 714 m interval airborne gravity data). Negative Bouguer anomalies were observed over the salt domes in Jazan (-3 mGal) and in Farsan (-30 mGal). (4) Boundaries of the potential salt domes extracted from zero tilt contour values on tilt derivative maps. (5) Shallow (GIS platform) of observations extracted from remote sensing, geophysical, GPS, and DEM datasets (items 1 through 5). Eight previously unidentified locations of potential near-surface salt domes were identified along the Red Sea coastline within the scene extent, five of

  12. Computed tomography-guided transpulmonary radiofrequency ablation for hepatocellular carcinoma located in hepatic dome.

    Science.gov (United States)

    Toyoda, Mitsuo; Kakizaki, Satoru; Horiuchi, Katsuhiko; Katakai, Kenji; Sohara, Naondo; Sato, Ken; Takagi, Hitoshi; Mori, Masatomo; Nakajima, Takahito

    2006-01-28

    To determine the feasibility of performing computed tomography (CT)-guided transpulmonary radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) located in the hepatic dome. A total of seven patients with HCC comprising seven nodules located in the hepatic dome were treated from April 2004 to December 2004. CT-guided transpulmonary RFA was performed using a cool-tip type electrode (Radionics Company) based on a standardized energy protocol. All tumors located in the hepatic dome were not detectable by the usual ultrasound (US) methods. The lesion diameters ranged from 15 to 27 mm. RFA was technically feasible in all the patients. The puncture procedure was performed twice or less and the total average performance time was 40.6 min. Local tumor control was achieved in all the patients. The necrosis diameter ranged from 25 to 35 mm. The mean follow-up period was 9.6 (7-14 mo) mo. There was no local recurrence at the follow-up points. Pneumothorax requiring pleural drainage was the main complication, which was observed in two of the seven patients (28.6%). However, it improved with chest drainage tube, and the tube could be removed within 2-3 d. No other major complications were observed. CT-guided puncture is useful for the treatment of tumors located in the hepatic dome which are hardly detectable by US, even though pneumothorax sometimes may occur as a complication. In the cases with adhesion in the pleura for which artificial pleural effusion methods are not appropriate, CT-guided RFA is thus considered to be an alternative treatment for HCC located in the hepatic dome.

  13. Enhanced depth imaging optical coherence tomography of the sclera in dome-shaped macula.

    Science.gov (United States)

    Imamura, Yutaka; Iida, Tomohiro; Maruko, Ichiro; Zweifel, Sandrine A; Spaide, Richard F

    2011-02-01

    To examine the posterior anatomic structure of eyes with dome-shaped macula using enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT). Retrospective observational case series. Patients with dome-shaped macula, a condition defined as convex elevation of the macula as compared with the surrounding staphylomatous region in a highly myopic eye, were identified through routine examinations using optical coherence tomography (OCT). EDI-OCT was used to examine their posterior anatomic changes. The scleral thickness was measured from the outer border of the choroid to the outer scleral border under the fovea and 3000 μm temporal to the fovea. The mean age of the 15 patients (23 eyes) was 59.3 (± 12.2) years, and the mean refractive error was -13.6 (± 5.0) diopters. The best-corrected visual acuity ranged from 20/15 to 20/800 (median: 20/30). Eight patients (53%) had dome-shaped macula bilaterally. The mean subfoveal scleral thickness in 23 eyes with dome-shaped macula was 570 (± 221) μm, and that in 25 eyes of 15 myopic patients with staphyloma but without dome-shaped macula was 281 (± 85) μm (P macula is the result of a relative localized thickness variation of the sclera under the macula in highly myopic patients, and it cannot be categorized into any of the known types of staphyloma. This finding suggests the ocular expansion in myopia may be more complex than previously thought. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. [Choroidal thickness assessment with SD-OCT in high myopia with dome-shaped macula].

    Science.gov (United States)

    Chebil, A; Ben Achour, B; Chaker, N; Jedidi, L; Mghaieth, F; El Matri, L

    2014-03-01

    To measure macular choroidal thickness (CT) using spectral-domain optical coherence tomography (SD-OCT) in highly myopic eyes with dome-shaped macula (DSM), and to investigate whether the choroid is thicker in these eyes compared to highly myopic eyes without MB. A cross-sectional study of 200 eyes was performed between January 2010 and June 2012. Twenty-four highly myopic eyes (12%) had a dome-shaped macula. All patients underwent a complete ophthalmological examination, SD-OCT (TOPCON 2000), and B-scan ultrasonography. OCT scans were analyzed in 7 sections, and subfoveal CT was measured manually between the Bruch's membrane and the internal aspect of the sclera. The 20 eyes with isolated dome-shaped macular were paired by age and axial length (AL) with 20 eyes without macular involvement. In the subgroup with isolated MB, the mean subfoveal CT was 101.86 μm (± 21.35 μm). A statistically significant negative correlation was found between CT and AL (r=-0.623, P=0.0001). The regression equation demonstrated a decrease of 8.3 μm per mm of AL. In the subgroup without MB, matched with the subgroup with MB by age (P=0.591), and AL (P=0.815), the mean subfoveal CT was 89.54 μm (± 20.12 μm). The comparison between the two subgroups found a statistically significant difference in subfoveal CT (Pmacula compared to highly myopic eyes without dome-shaped macula. These findings suggest that abnormalities of the choroid may play a role in the pathogenesis of dome-shaped macula. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  15. Mode shape expansions for the dynamic testing of cable domes considering random pretension deviations

    Science.gov (United States)

    Wu, Xiaoshun; Deng, Hua; Zhu, Dexi

    2017-04-01

    Cable domes maintain their structural stability and deformation resistance substantially depending on the geometrical stiffness contributed by pretension. Dynamic testing can be employed to monitor the possible stiffness degeneration caused by pretension deviations in existing cable domes. The measured incomplete mode shapes should be expanded for effectively evaluating the actual structural stiffness. However, conventional methods lose effectiveness for expanding mode shapes of cable domes whose modes are sensitive to the pretension deviations. A novel method is developed in this paper to expand the incomplete mode shapes of existing cable domes with random pretension deviations. For a monitored target mode of the existing structure, its mode shape can be approximately expressed as a linear combination of a few mode shapes of the ideal structure. Once their combinational coefficients are determined based on the measured incomplete mode shape, the expansion of this target mode is achieved. Two key steps are included: the determination of these so-called contribution modes and the estimation of their combinational coefficients. For the prescribed limit values of equivalent member length errors adopted to simulate random pretension deviations, contribution modes can be determined by considering the mode shape variations and mode jumpings. A proposed contribution mode effective independence (CMEI) method is further put forward to obtain the best estimate of combinational coefficients and the optimal layout of sensors. The numerical example of a cable dome illustrates the invalidation of the conventional expansion methods when random pretension deviations are considered. In contrast, the method proposed in this paper is validated to be effective and reliable even in the cases of severe modal variations and high noise levels.

  16. Persistent River Basin Disequilibrium in a Cratonic Landscape: Ozark Dome, USA

    Science.gov (United States)

    Beeson, H. W.; McCoy, S. W.; Keen-Zebert, A.

    2015-12-01

    Quantitative research on landscape evolution has focused on tectonically active landscapes, leaving the pace and primary drivers of topographic change in tectonically quiescent environments, which make up the majority of Earth's surface, poorly understood. We use topographic analysis and a characteristic metric of river basin geometry, χ, to test the hypothesis that river basin dynamics, including divide migration and stream capture, can cause transient pulses of incision and large gradients in erosion rate, which in turn influence the morphology of cratonic landscapes. In testing this hypothesis, we describe and interpret the disequilibrium observed in river networks draining a typical low-elevation cratonic landscape, the Ozark dome, USA and propose alternative mechanisms to climate and tectonics that generate and sustain large-scale landscape disequilibrium. The Ozark dome was uplifted in the fore-bulge of the Ouachita orogeny and lies south of the extent of glaciation and primarily north of eustatic sea-level changes. The Ozarks have not experienced significant tectonic activity since the late Paleozoic. Landscape response times predicted by stream-power river incision models would suggest that landscapes subjected to consistent, low rates of isostatic uplift should be close to steady state. Yet, rivers draining the Ozark dome appear to be in disequilibrium. Anomalous stream network topology, variable relief across the dome, cross-divide topographic asymmetry that corresponds with large cross-divide gradients in χ, and the prevalence of multiple flights of strath terraces suggest transient and non-uniform bedrock incision rates. Our results suggest that erosional competition between river basins drive much of the observed topographic asymmetry and the in-situ formation of high-elevation, low-relief surfaces on the Ozark dome. This implies that basin dynamics, rather than tectonics, lithology, or climate, may set the large-scale morphology of some cratonic

  17. 40 CFR 230.25 - Salinity gradients.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Salinity gradients. 230.25 Section 230... Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.25 Salinity gradients. (a) Salinity... fresh or salt water may change existing salinity gradients. For example, partial blocking of the...

  18. Saline nasal irrigation for upper respiratory conditions.

    Science.gov (United States)

    Rabago, David; Zgierska, Aleksandra

    2009-11-15

    Saline nasal irrigation is an adjunctive therapy for upper respiratory conditions that bathes the nasal cavity with spray or liquid saline. Nasal irrigation with liquid saline is used to manage symptoms associated with chronic rhinosinusitis. Less conclusive evidence supports the use of spray and liquid saline nasal irrigation to manage symptoms of mild to moderate allergic rhinitis and acute upper respiratory tract infections. Consensus guidelines recommend saline nasal irrigation as a treatment for a variety of other conditions, including rhinitis of pregnancy and acute rhinosinusitis. Saline nasal irrigation appears safe, with no reported serious adverse events. Minor adverse effects can be avoided with technique modification and salinity adjustment.

  19. Geologic technical assessment of the Chacahoula Salt Dome, Louisiana, for potential expansion of the U.S. strategic petroleum reserve.

    Energy Technology Data Exchange (ETDEWEB)

    Snider, Anna C.; Rautman, Christopher Arthur; Looff, Karl M. (Geologic Consultant, Lovelady, TX)

    2006-03-01

    The Chacahoula salt dome, located in southern Louisiana, approximately 66 miles southwest of New Orleans, appears to be a suitable site for a 160-million-barrel-capacity expansion facility for the U.S. Strategic Petroleum Reserve, comprising sixteen 10-million barrel underground storage caverns. The overall salt dome appears to cover an area of some 1800 acres, or approximately 2.8 square miles, at a subsea elevation of 2000 ft, which is near the top of the salt stock. The shallowest known salt is present at 1116 ft, subsea. The crest of the salt dome is relatively flatlying, outward to an elevation of -4000 ft. Below this elevation, the flanks of the dome plunge steeply in all directions. The dome appears to comprise two separate spine complexes of quasi-independently moving salt. Two mapped areas of salt overhang, located on the eastern and southeastern flanks of the salt stock, are present below -8000 ft. These regions of overhang should present no particular design issues, as the conceptual design SPR caverns are located in the western portion of the dome. The proposed cavern field may be affected by a boundary shear zone, located between the two salt spines. However, the large size of the Chacahoula salt dome suggests that there is significant design flexibility to deal with such local geologic issues.

  20. DOME-SHAPED MACULA IN MYOPIC EYES: Twelve-Month Follow-up.

    Science.gov (United States)

    Lorenzo, Daniel; Arias, Luis; Choudhry, Netan; Millan, Eduard; Flores, Ignacio; Rubio, Marcos J; Cobos, Estefanía; García-Bru, Pere; Filloy, Alejandro; Caminal, Josep M

    2017-04-01

    To study the long-term clinical course of dome-shaped macula in myopic eyes and to evaluate treatment efficacy for subretinal fluid (SRF) as a related complication. A retrospective, single-center consecutive case series study was conducted. The authors analyzed myopic eyes with dome-shaped macula in patients who presented for evaluation of decreased vision. Dome-shaped macula was defined as a convexity of the retina-choroidal macular complex seen on spectral domain optical coherence tomography images. All patients were followed for at least 12 months (mean, 25 months). Fluorescein angiography and/or indocyanine green angiography were performed in cases with SRF to rule out choroidal neovascularization. A total of 56 dome-shaped macula eyes from 36 patients were included in the study (bilateral in 55% of patients). Mean patient age was 56.9 ± 13.1 years. The mean spherical equivalent was -9.1 ± 6.0 diopters; 53% of eyes were considered highly myopic (>-6 diopters) and 47% of eyes were mildly myopic. In most cases (37 eyes; 66.1%), the dome-shaped macula was detected on vertical spectral domain optical coherence tomography scan patterns. No significant changes (P ≥ 0.1) were observed in mean best-corrected visual acuity or mean central foveal thickness from baseline to final follow-up. Subretinal fluid was present in 29 eyes (51.8%) at baseline, with no differences in best-corrected visual acuity in eyes with and without SRF (P ≥ 0.05). Nineteen of the 29 SRF eyes were treated: 8 underwent low-fluence photodynamic therapy, whereas 7 received bevacizumab, and 4 ranibizumab. No significant differences were found between treated and untreated SRF eyes in best-corrected visual acuity improvement (P ≥ 0.1), or complete resolution of SRF (P ≥ 0.1). Likewise, photodynamic therapy did not yield any significant benefit versus untreated eyes in best-corrected visual acuity or improvement of SRF. Dome-shaped macula is a condition associated with myopic eyes that seems

  1. Finite Element Model of a Two-Phase Non-Newtonian Thixotropic Fluid: Mount St. Helens Lava Dome

    Science.gov (United States)

    Vincent, P.; Zevada, P.

    2011-12-01

    Extrusion of highly viscous lavas that spread laterally and form lava domes in the craters of large volcanoes is associated with significant volcanic hazards. Gas overpressure driven fragmentation of the lava dome or collapse and slumping of marginal sections or the entire mass of the dome can trigger dangerous pyroclastic flows that threaten surrounding populations up to tens of kilometers away. The rate of lava dome growth in the mature state of the dome evolution is often oscillatory. Relatively quiescent episodes are terminated by renewed extrusion and emplacement of exogenous "lobes" or "spines" of lava on the surface of the dome. Emplacement of new lobes is preceded by pressurization of magma in the magmatic conduit that can trigger volcanic eruptions and is preceded by crater floor deformation (e.g. Swanson and Holcombe, 1990). This oscillatory behavior was previously attributed primarily to crystallization kinetics and gas exsolution generating cyclic overpressure build-ups. Analogue modeling of the lava domes has revealed that the oscillatory growth rate can be reproduced by extrusion of isothermal, pseudoplastic and thixotropic plaster of Paris (analogue material for the magma) on a sand layer (analogue material for the unconsolidated deposits of the crater floor). The patterns of dome growth of these models closely correspond to both the 1980-1985 and 2004-2005 growth episodes of Mt. St. Helens lava dome (Swanson and Holcombe, 1990; Major et al., 2005). They also suggest that the oscillatory growth dynamics of the lavas can be explained by the mechanical interaction of the non-Newtonian magma with the frictional and deformable substrate below the lava dome rather than complex crystallization kinetics (e.g. Melnik and Sparks, 1999). In addition, these results suggest that the renewed growth episode of Mt. St. Helens dome in 2006 could be associated with an even higher degree of magma pressurization in the conduit than occurred during the 1980 - 1986

  2. Seafloor doming driven by degassing processes unveils sprouting volcanism in coastal areas

    Science.gov (United States)

    Passaro, Salvatore; Tamburrino, Stella; Vallefuoco, Mattia; Tassi, Franco; Vaselli, Orlando; Giannini, Luciano; Chiodini, Giovanni; Caliro, Stefano; Sacchi, Marco; Rizzo, Andrea Luca; Ventura, Guido

    2016-03-01

    We report evidences of active seabed doming and gas discharge few kilometers offshore from the Naples harbor (Italy). Pockmarks, mounds, and craters characterize the seabed. These morphologies represent the top of shallow crustal structures including pagodas, faults and folds affecting the present-day seabed. They record upraise, pressurization, and release of He and CO2 from mantle melts and decarbonation reactions of crustal rocks. These gases are likely similar to those that feed the hydrothermal systems of the Ischia, Campi Flegrei and Somma-Vesuvius active volcanoes, suggesting the occurrence of a mantle source variously mixed to crustal fluids beneath the Gulf of Naples. The seafloor swelling and breaching by gas upraising and pressurization processes require overpressures in the order of 2-3 MPa. Seabed doming, faulting, and gas discharge are manifestations of non-volcanic unrests potentially preluding submarine eruptions and/or hydrothermal explosions.

  3. Thermic model to predict biogas production in unheated fixed-dome digesters buried in the ground

    DEFF Research Database (Denmark)

    Terradas-Ill, Georgina; Cuong, Pham Hung; Triolo, Jin Mi

    2014-01-01

    In many developing countries, simple biogas digesters are used to produce energy for domestic purposes from anaerobic digestion of animal manure. We developed a simple, one-dimensional (1-D), thermal model with easily-available input data for unheated, unstirred, uninsulated, fixed-dome digesters...... buried in the soil to study heat transfer between biogas digester and its surroundings. The predicted temperatures in the dome, biogas and slurry inside the digester and the resulting biogas production are presented and validated. The model was well able to estimate digester temperature (linear slope...... nearly 1, R2 0.96). Model validation for methane production gave root-mean-square error (RMSE) of 54.4 L CH4 digester-1 day-1 and relative-root-mean-square errors (rRMSEP(%)) of 35.4%. The validation result was considerably improved if only using winter data (RMSE = 26.1 L CH4 digester-1 day-1; r...

  4. Percutaneous CT-Guided Ablation in the Hepatic Dome: Artificially Induced Pneumothorax for Safe Transpleural Access

    Directory of Open Access Journals (Sweden)

    Leonardo Guedes Moreira Valle

    2015-01-01

    Full Text Available Ablative therapies have become a great alternative to surgical treatment of hepatic nodules. Some technical difficulties may negatively influence the effectiveness of this therapy, such as lesions located near the diaphragm. The transthoracic approach is commonly used to access these lesions. However, it is associated with an increased risk of complications, such as pneumothorax, hemothorax, alveolar bleeding, and others.We report a case of a radiofrequency ablation of a lesion in the hepatic dome, where an artificially induced pneumothorax was performed to guarantee a safe and effective access. The air was easily injected by a spinal needle and later aspirated by a single-lumen catheter. Induced pneumothorax shoud be considered in ablation of hepatic dome lesions, mainly when the transhepatic access is not appropriate.

  5. Geometric and Optic Characterization of a Hemispherical Dome Port for Underwater Photogrammetry

    Directory of Open Access Journals (Sweden)

    Fabio Menna

    2016-01-01

    Full Text Available The popularity of automatic photogrammetric techniques has promoted many experiments in underwater scenarios leading to quite impressive visual results, even by non-experts. Despite these achievements, a deep understanding of camera and lens behaviors as well as optical phenomena involved in underwater operations is fundamental to better plan field campaigns and anticipate the achievable results. The paper presents a geometric investigation of a consumer grade underwater camera housing, manufactured by NiMAR and equipped with a 7′′ dome port. After a review of flat and dome ports, the work analyzes, using simulations and real experiments, the main optical phenomena involved when operating a camera underwater. Specific aspects which deal with photogrammetric acquisitions are considered with some tests in laboratory and in a swimming pool. Results and considerations are shown and commented.

  6. Magma ascent and lava dome evolution at Volcán de Colima, Mexico

    Science.gov (United States)

    Varley, N. R.; Arámbula, R.; Lavallée, Y.; Bernstein, M.; Ryan, A. G.; Maskell, A.

    2009-12-01

    The transition between explosive and effusive activity can be triggered by subtle variations in parameters which dictate the efficiency and speed of degassing from an ascending magma body. Indirect methods have to be utilized to constrain these parameters, to test and refine numerical models, which ultimately permit a more powerful interpretation of monitoring data. Recent activity at Volcán de Colima has included many transitions between different regimes, offering a great opportunity to examine conduit processes. Explosive activity peaked in 2005 with 30 Vulcanian eruptions producing pyroclastic flows, some reaching >5km from the volcano. Each event was associated with a swarm of long-period (LP) seismic events. A poor correlation between swarm characteristics and the size of the explosion suggests independence between the source mechanisms of each phenomenon. The LP events were divided into 10 families, all of which reappeared in different swarms and the majority continued to occur after the Vulcanian explosion. This is evidence of the complexity of the upper edifice, with the source regions for the LP events remaining unaffected by the explosions. We believe they are produced by brittle deformation once a certain strain-rate threshold has been surpassed. The explosions were associated with rapidly ascending magma bodies that were degassing and crystallizing near the surface, each one being destroyed in the subsequent explosion. Magma sometimes reached the crater, with small short-lived domes being observed. In some cases a post-explosion increase in amplitude of the LP events might have reflected an increase in effusion rate after an unloading of material higher in the vent. Volcán de Colima has produced 5 episodes of effusive activity in the last 11 years. These have been of variable duration and intensity, with over 2 orders of magnitude variation in the effusion rate. The current phase has been characterised by a remarkably sustained (from Jan. 07 to at

  7. Initial stresses in two-layer metal domes due to imperfections of their production and assemblage

    Directory of Open Access Journals (Sweden)

    Lebed Evgeniy Vasil’evich

    2015-04-01

    Full Text Available The process of construction of two-layer metal domes is analyzed to illustrate the causes of initial stresses in the bars of their frames. It has been noticed that it is impossible to build such structures with ideal geometric parameters because of imperfections caused by objective reasons. These imperfections cause difficulties in the process of connection of the elements in the joints. The paper demonstrates the necessity of fitting operations during assemblage that involve force fitting and yield initial stresses due to imperfections. The authors propose a special method of computer modeling of enforced elimination of possible imperfections caused by assemblage process and further confirm the method by an analysis of a concrete metal dome.

  8. A vibration-based health monitoring program for a large and seismically vulnerable masonry dome

    Science.gov (United States)

    Pecorelli, M. L.; Ceravolo, R.; De Lucia, G.; Epicoco, R.

    2017-05-01

    Vibration-based health monitoring of monumental structures must rely on efficient and, as far as possible, automatic modal analysis procedures. Relatively low excitation energy provided by traffic, wind and other sources is usually sufficient to detect structural changes, as those produced by earthquakes and extreme events. Above all, in-operation modal analysis is a non-invasive diagnostic technique that can support optimal strategies for the preservation of architectural heritage, especially if complemented by model-driven procedures. In this paper, the preliminary steps towards a fully automated vibration-based monitoring of the world’s largest masonry oval dome (internal axes of 37.23 by 24.89 m) are presented. More specifically, the paper reports on signal treatment operations conducted to set up the permanent dynamic monitoring system of the dome and to realise a robust automatic identification procedure. Preliminary considerations on the effects of temperature on dynamic parameters are finally reported.

  9. Fingerprinting groundwater salinity sources in the Gulf Coast Aquifer System, USA

    Science.gov (United States)

    Chowdhury, Ali H.; Scanlon, Bridget R.; Reedy, Robert C.; Young, Steve

    2018-02-01

    Understanding groundwater salinity sources in the Gulf Coast Aquifer System (GCAS) is a critical issue due to depletion of fresh groundwater and concerns for potential seawater intrusion. The study objective was to assess sources of groundwater salinity in the GCAS using ˜1,400 chemical analyses and ˜90 isotopic analyses along nine well transects in the Texas Gulf Coast, USA. Salinity increases from northeast (median total dissolved solids (TDS) 340 mg/L) to southwest (median TDS 1,160 mg/L), which inversely correlates with the precipitation distribution pattern (1,370- 600 mm/yr, respectively). Molar Cl/Br ratios (median 540-600), depleted δ2H and δ18O (-24.7‰, -4.5‰) relative to seawater (Cl/Br ˜655 and δ2H, δ18O 0‰, 0‰, respectively), and elevated 36Cl/Cl ratios (˜100), suggest precipitation enriched with marine aerosols as the dominant salinity source. Mass balance estimates suggest that marine aerosols could adequately explain salt loading over the large expanse of the GCAS. Evapotranspiration enrichment to the southwest is supported by elevated chloride concentrations in soil profiles and higher δ18O. Secondary salinity sources include dissolution of salt domes or upwelling brines from geopressured zones along growth faults, mainly near the coast in the northeast. The regional extent and large quantities of brackish water have the potential to support moderate-sized desalination plants in this location. These results have important implications for groundwater management, suggesting a current lack of regional seawater intrusion and a suitable source of relatively low TDS water for desalination.

  10. A 220 kyr record of Pb isotopes at Dome C Antarctica from analyses of the EPICA ice core

    Science.gov (United States)

    Vallelonga, P.; Gabrielli, P.; Rosman, K. J. R.; Barbante, C.; Boutron, C. F.

    2005-01-01

    Pb isotopic compositions and Pb and Ba concentrations are reported in EPICA Dome C ice core samples dating to 220 kyr BP, indicating that Pb isotopic compositions in Antarctic ice vary with changing climate. 206Pb/207Pb ratios decrease during glacial periods, with the lowest values occurring during colder climatic periods (stages 2, 4 and 6) and the Holocene. Low Pb concentrations (10 pg/g) were found during cold climatic periods. Ba, a proxy for mineral dust, was used to determine that dust usually accounts for ~70% of Pb in Dome C ice, while the remaining ~30% was attributed to volcanic emissions. Pb isotopic compositions at Dome C differ from those reported in pre-industrial ice from other Antarctic locations, due to greater proportions of dust Pb at Dome C.

  11. Joint influences of aerodynamic flow field and aerodynamic heating of the dome on imaging quality degradation of airborne optical systems.

    Science.gov (United States)

    Xiao, Haosu; Zuo, Baojun; Tian, Yi; Zhang, Wang; Hao, Chenglong; Liu, Chaofeng; Li, Qi; Li, Fan; Zhang, Li; Fan, Zhigang

    2012-12-20

    We investigated the joint influences exerted by the nonuniform aerodynamic flow field surrounding the optical dome and the aerodynamic heating of the dome on imaging quality degradation of an airborne optical system. The Spalart-Allmaras model provided by FLUENT was used for flow computations. The fourth-order Runge-Kutta algorithm based ray tracing program was used to simulate optical transmission through the aerodynamic flow field and the dome. Four kinds of imaging quality evaluation parameters were presented: wave aberration of the exit pupil, point spread function, encircled energy, and modulation transfer function. The results show that the aero-optical disturbance of the aerodynamic flow field and the aerodynamic heating of the dome significantly affect the imaging quality of an airborne optical system.

  12. Percutaneous radiofrequency ablation of liver cancer in the hepatic dome using the intrapleural fluid infusion technique.

    Science.gov (United States)

    Kondo, Y; Yoshida, H; Tateishi, R; Shiina, S; Kawabe, T; Omata, M

    2008-08-01

    Intrapleural fluid infusion improves ultrasonographic visualization of tumours in the hepatic dome. The aim of this study was to assess the safety and long-term efficacy of ultrasonographically guided percutaneous radiofrequency ablation for tumours in the hepatic dome with intrapleural infusion. Of 2575 patients with hepatocellular carcinoma or hepatic metastases treated with radiofrequency ablation, intrapleural fluid infusion was performed in 587 patients for tumours in the hepatic dome. After the tip of a 14-G metallic needle was positioned in the pleural cavity under ultrasonographic guidance, 500-1000 ml of 5 per cent glucose solution was infused in 5-15 min. Radiofrequency ablation was performed using an internally cooled electrode. Long-term results were evaluated in 347 patients with a single hepatocellular carcinoma who were naive to any treatment. Intrapleural fluid infusion was successfully performed in all 587 patients. The major complication rate on a per tumour basis was similar for patients treated with and without intrapleural infusion (1.6 versus 1.6 per cent; P = 0.924). The overall and recurrence-free survival were both similar for naive patients with a single hepatocellular carcinoma treated with and without intrapleural infusion (P = 0.429 and P = 0.109 respectively). Intrapleural infusion was not associated with lower overall survival in multivariable analysis. With intrapleural fluid infusion, radiofrequency ablation for tumours in the hepatic dome was safe and effective, resulting in satisfactory overall and recurrence-free survival. Copyright (c) 2008 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

  13. Transmalleolar Approach for Arthroscopy-Assisted Headless Screw Fixation of an Osteochondral Talar Dome Fracture.

    Science.gov (United States)

    Izadi, Ebrahim; Anwar, Rahij; Phillips, Sarah; Kavarthapu, Venu

    2018-02-15

    Displaced osteochondral fractures of the body of talus quite often require a malleolar osteotomy to gain access to the fracture fragment during internal fixation. We describe a case report in which access to a displaced osteochondral fracture of the lateral talar dome was achieved using an arthroscopy-assisted fibular tunnel approach. This technique resulted in satisfactory fracture healing and a satisfactory clinical outcome. Copyright © 2017 The American College of Foot and Ankle Surgeons. All rights reserved.

  14. The Fulldome Curriculum for the Spitz SciDome Digital Planetarium: Volume 2

    Science.gov (United States)

    Bradstreet, David H.; Sanders, S. J.; Huggins, S.

    2014-01-01

    The Spitz Fulldome Curriculum (FDC) for the SciDome digital planetarium ushered in a new and innovative way to present astronomical pedagogy via its use of the unique teaching attributes of the digital planetarium. In the case of the FDC, which uses the ubiquitous Starry Night planetarium software as its driving engine, these engaging and novel teaching techniques have also been made usable to desktop computers and flat-screen video projectors for classroom use. Volume 2 of the FDC introduces exciting new classes and mini-lessons to further enlighten and invigorate students as they struggle with often difficult three dimensional astronomical concepts. Additionally, other topics with related astronomical ties have been created to integrate history into planetarium presentations. One of the strongest advantages of the SciDome is its use of Starry Night as its astronomical engine. With it students can create their own astronomical configurations in the computer lab or at home, using the PC or Mac version. They can then simply load their creations onto the SciDome planetarium system and display them for their classmates on the dome. This poster will discuss and illustrate some of the new content that has been developed for Volume 2. Topics covered in Volume 2 include eclipses, plotting planet locations on a curtate orbit chart by observing their positions in the sky, time and timekeeping (including sidereal day, hour angles, sidereal time, LAST, LMST, time zones and the International Date Line), teaching to the Boy Scout Merit Badge requirements, plotting scale analemmas on the surface of planets and interpreting them, precession, astronomical events in revolutionary Boston, the Lincoln Almanac Trial, eclipsing binaries, lunar librations, a trip through the universe, watching the speed of light move in real time, stellar sizes and the Milky Way.

  15. A Virtual Environment System for the Comparison of Dome and HMD Systems

    Science.gov (United States)

    Chen, Jian; Harm, Deboran L.; Loftin, R. Bowen; Lin, Ching-yao; Leiss, Ernst L.

    2002-01-01

    For effective astronaut training applications, choosing the right display devices to present images is crucial. In order to assess what devices are appropriate, it is important to design a successful virtual environment for a comparison study of the display devices. We present a comprehensive system for the comparison of Dome and head-mounted display (HMD) systems. In particular, we address interactions techniques and playback environments.

  16. The meaning of sense of place: The community of Vredefort Dome and Parys, Free State

    Directory of Open Access Journals (Sweden)

    T. Erasmus

    2015-12-01

    Full Text Available The Vredefort Dome was declared a World Heritage Site by the United Nations Educational, Scientific and Cultural Organization (UNESCO in 2005. This status has led to an increase in tourism to the adjacent town of Parys and the Dome as well as an increase in developers that could change the character of the area. Therefore, the sense of place of the residents of, and tourists to the area requires consideration in order to find a balance when development takes place. Sense of place refers to the unique features that gives the area its character and the manner in which people relate to these features. This study investigated the participants’ understanding of sense of place of the area under study. The participants consisted of residents and tourists from Parys and the Dome. The non-probability sampling technique, amongst other, was used. The qualitative research method was utilised to gather data which was analysed through content analysis. Thereupon, themes were identified and interpreted. The connotation the participants attached to sense of place was categorised into three broad themes: affective, anthropogenic and the physical environment. The participants showed a special awareness towards protecting the character, nature and history of the area. Sense of place is rarely considered when development is considered. The findings of this study could be used as a guideline for developers in the area. A better understanding of the relationship between place and the attributes individuals assign to Parys and the Vredefort Dome World Heritage Site may help the stakeholders to acquire enhanced approaches to address, identify and engage the community (both residents and tourists in conservation and future planning processes to ensure the well-being of all concerned.

  17. Computational Analysis of Natural Ventilation Flows in Geodesic Dome Building in Hot Climates

    Directory of Open Access Journals (Sweden)

    Zohreh Soleimani

    2016-08-01

    Full Text Available For centuries, dome roofs were used in traditional houses in hot regions such as the Middle East and Mediterranean basin due to its thermal advantages, structural benefits and availability of construction materials. This article presents the computational modelling of the wind- and buoyancy-induced ventilation in a geodesic dome building in a hot climate. The airflow and temperature distributions and ventilation flow rates were predicted using Computational Fluid Dynamics (CFD. The three-dimensional Reynolds-Averaged Navier-Stokes (RANS equations were solved using the CFD tool ANSYS FLUENT15. The standard k-epsilon was used as turbulence model. The modelling was verified using grid sensitivity and flux balance analysis. In order to validate the modelling method used in the current study, additional simulation of a similar domed-roof building was conducted for comparison. For wind-induced ventilation, the dome building was modelled with upper roof vents. For buoyancy-induced ventilation, the geometry was modelled with roof vents and also with two windows open in the lower level. The results showed that using the upper roof openings as a natural ventilation strategy during winter periods is advantageous and could reduce the indoor temperature and also introduce fresh air. The results also revealed that natural ventilation using roof vents cannot satisfy thermal requirements during hot summer periods and complementary cooling solutions should be considered. The analysis showed that buoyancy-induced ventilation model can still generate air movement inside the building during periods with no or very low wind.

  18. Mucinous cystadenoma of the dome of urinary bladder: A rare case report

    Directory of Open Access Journals (Sweden)

    Bapuji S Gedam

    2015-01-01

    Full Text Available Mucinous cystadenoma of the urinary bladder is a very rare tumor and only a handful of cases have been described in the literature. It can easily be missed on cystoscopic examination as the lesion is not intramucosal. In addition, extensive workup is required to rule out borderline or frank malignant neoplasm elsewhere in the body. Due to its scarcity and diagnostic challenges, we report a mucinous benign cystic lesion arising in the dome of the urinary bladder.

  19. Evolution of under-pressure in Bravo Dome and its implications for geological carbon storage

    Science.gov (United States)

    Akhbari, D.; Hesse, M. A.

    2016-12-01

    Geological carbon storage has the potential to reduce anthropogenic CO2 emissions, if large volumes can be injected. Storage capacity is generally thought to be limited by regional pressure build-up in the subsurface, although natural CO2 reservoirs are commonly under-pressured. To understand the processes that lead to the development of under-pressure we have studied the Bravo Dome natural CO2 reservoir. Pre-production pressures show that Bravo Dome is divided into compartments (Figure a, b, and c) that appear not communicate with each other and the ambient aquifer. While this allows the preservation of under-pressures, it raises question about the emplacement of the reservoir. Noble gas signatures suggest that the reservoir filled from west to east rather than each reservoir being charged individually. Such uni-directional filling is consistent with an eastward decline in pre-production pressure (Figure d). However, this requires that the currently isolated compartments must have been connected during the emplacement. To preserve the overall pressure gradients this connectivity must have been lost relatively quickly after emplacement ended. We suggest that hydraulic fracturing connected the compartments during emplacement and that a pressure drop due to CO2 dissolution helped seal the compartments afterwards. To explore the dynamics, we have developed a numerical model of this fill-fracture-spill-seal process. Initial results suggest that a pressure drop after CO2 emplacement due to continued CO2 dissolution only occurs if the emplacement was very rapid. Understanding the pressure evolution at Bravo Dome is important as Bravo Dome has stored a very large amount of CO2 on millennial time scales, but it does not correspond to the current conception of an ideal storage formation such as Sleipner site in the North Sea, which is laterally open and has high permeability. This demonstrates that successful CO2 storage is possible in a broader range of formations that

  20. Accretion of continental extensional zone and development of Rehamna metamorphic dome (Morocco)

    Science.gov (United States)

    Chopin, F.; Schulmann, K.; Corsini, M.; El Houicha, M.; Ghienne, J. F.; El Attari, M.

    2009-04-01

    The Rehamna massif is a part of the Morocco Variscan belt where the metamorphic infrastructure has been exhumed in a continental accretionary wedge. The relationships between infra- and supra-structure tectonics originate by thickening of intra-continental Devonian and Carboniferous (Mississipian) basin. Two superposed deformations probably related to plate configuration changes have been identified. The first one corresponds to the development of the Barrovian metamorphism with a climax estimated at 0.5-0.7 Gpa, 500-550°C (litt.). The thickening of thermally preheated crust is related to a SW vergent nappe stacking in the orogenic infrastructure. This event terminates with large scale folding and extrusion of high grade rocks forming a large scale E-W trending metamorphic dome surrounded by un-metamorphosed Lower Palaeozoic rocks of orogenic suprastructre indicating complete decoupling between the two crustal layers. The second E-W shortening along Western Meseta Shear Zone event is responsible for the development of important deformation gradient orthogonal to the metamorphic dome axis. It is marked by an increase of the strain intensity towards the Cambrian rigid buttress located further west. This deformation gradient is marked by mechanical coupling and gentle folding of infra- and supra-structure in the east, development of slaty cleavage in the central part of the dome and intense deformation front close to the western buttress. Here the superposed fold pattern results in accentuation of asymmetrical NE-SW trending metamorphic dome close to the buttress and to further exhumation of deepest rocks associated with subsequent elevation and folding of metamorphic isograds. 40Ar/39Ar dating reveals that the cooling associated with the first thermal event occurred at around 310 Ma (biotite) while the second thermal event yields typical Alleghanian age around 280 Ma (muscovite). This last thermal event is contemporaneous with magmatic intrusions and continental

  1. Interaction of mid-latitude air masses with the polar dome area during RACEPAC and NETCARE

    Science.gov (United States)

    Bozem, Heiko; Hoor, Peter; Koellner, Franziska; Kunkel, Daniel; Schneider, Johannes; Schulz, Christiane; Herber, Andreas; Borrmann, Stephan; Wendisch, Manfred; Ehrlich, Andre; Leaitch, Richard; Willis, Megan; Burkart, Julia; Thomas, Jennie; Abbatt, Jon

    2016-04-01

    We present aircraft based trace gas measurements in the Arctic during RACEPAC (2014) and NETCARE (2014 and 2015) with the Polar 6 aircraft of Alfred Wegener Institute (AWI) covering an area from 134°W to 17°W and 68°N to 83°N. We focus on cloud, aerosol and general transport processes of polluted air masses into the high Arctic. Based on CO and CO2 measurements and kinematic 10-day back trajectories as well as Flexpart particle dispersion modeling we analyze the transport regimes of mid-latitude air masses traveling to the high Arctic prevalent during spring (RACEPAC 2014, NETCARE 2015) and summer (NETCARE 2014). In general more northern parts of the high Arctic (Lat > 75°N) were relatively unaffected from mid-latitude air masses. In contrast, regions further south are influenced by air masses from Asia and Russia (eastern part of Canadian Arctic and European Arctic) as well as from North America (central and western parts of Canadian Arctic). The transition between the mostly isolated high Arctic and more southern regions indicated by tracer gradients is remarkably sharp. This allows for a chemical definition of the Polar dome based on the variability of CO and CO2 as a marker. Isentropic surfaces that slope from the surface to higher altitudes in the high Arctic form the polar dome that represents a transport barrier for mid-latitude air masses to enter the lower troposphere in the high Arctic. Synoptic-scale weather systems frequently disturb this transport barrier and foster the exchange between air masses from the mid-latitudes and polar regions. This can finally lead to enhanced pollution levels in the lower polar troposphere. Mid-latitude pollution plumes from biomass burning or flaring entering the polar dome area lead to an enhancement of 30% of the observed CO mixing ratio within the polar dome area.

  2. DOME-SHAPED MACULA WITH THICKENED CHOROID IN AN EMMETROPIC PATIENT.

    Science.gov (United States)

    Kedkovid, Napang; Afshar, Armin R; Damato, Bertil E; Stewart, Jay M

    2015-01-01

    To report a rare case of bilateral dome-shaped macula in an emmetropic patient. Clinical case report and literature review. A 42-year-old woman presented with a history of blurred vision in the right eye. Visual acuity was 20/30 in the right eye and 20/20 in the left eye. Intraocular pressure and anterior segment were unremarkable. Fundus examination revealed dull macular reflex and subretinal fluid nasal to the fovea in the right eye and a hyperpigmented area inferotemporal to the fovea in the left eye. Spectral domain optical coherence tomography showed subretinal fluid under the fovea in the right eye and elevation of the macula with increased choroidal thickness in both eyes. Fluorescein angiography revealed abnormal hyperfluorescence without any leakage in both eyes. B-scan ultrasound showed irregular globe contour with high internal reflectivity and dome-shaped lesions at the posterior pole in both eyes. Axial length was 24.6 mm in the right eye and 25.6 mm in the left eye. Although most commonly reported in myopic eyes, dome-shaped macula can occur in an emmetropic patient and can be associated with subretinal fluid.

  3. Large-scale doming on Europa: A model of formation of Thera Macula

    Science.gov (United States)

    Mével, Loïc; Mercier, Eric

    2007-05-01

    Since Galileo spacecraft reveals Europa's surface at high and medium resolutions, deformation and processes affecting the relatively young surface have been more accurately defined. This work reports the observations carried out on a large-scale feature of the south hemisphere, Thera Macula. It is shown that Thera presents common points with many other features including small-scale domes, lenticulae and large-scale chaotic areas (disrupted ancient surfaces lying on a dark matrix), but remains singular through its asymmetric morphology. On the basis of observations, we propose a scenario for the setting of Thera Macula. It involves a large-scale doming (40-70 km in radius) of the pre-existing surface associated with ductile deformations, and the consecutive collapse of the created megadome associated with brittle disruption of blocks and flow of low viscosity material over the surrounding ridged plains. The processes responsible for each stage of the proposed scenario have been investigated. Both cryomagmatic and diapiric origins are discussed and confronted by observations. Finally, comparison of similar features at various scales suggests that Thera Macula by its originalities (asymmetry, rounding bulge) may have preserved the intermediate stages of the formation of subcircular chaos at least up to about 50 km in radius. A common evolution and endogenic origin for multi-scale hot spot features is proposed: (1) the doming stage, (2) the collapse and extrusion stage and (3) the relaxation stage.

  4. Modeling the modified drug release from curved shape drug delivery systems - Dome Matrix®.

    Science.gov (United States)

    Caccavo, D; Barba, A A; d'Amore, M; De Piano, R; Lamberti, G; Rossi, A; Colombo, P

    2017-12-01

    The controlled drug release from hydrogel-based drug delivery systems is a topic of large interest for research in pharmacology. The mathematical modeling of the behavior of these systems is a tool of emerging relevance, since the simulations can be of use in the design of novel systems, in particular for complex shaped tablets. In this work a model, previously developed, was applied to complex-shaped oral drug delivery systems based on hydrogels (Dome Matrix®). Furthermore, the model was successfully adopted in the description of drug release from partially accessible Dome Matrix® systems (systems with some surfaces coated). In these simulations, the erosion rate was used asa fitting parameter, and its dependence upon the surface area/volume ratio and upon the local fluid dynamics was discussed. The model parameters were determined by comparison with the drug release profile from a cylindrical tablet, then the model was successfully used for the prediction of the drug release from a Dome Matrix® system, for simple module configuration and for module assembled (void and piled) configurations. It was also demonstrated that, given the same initial S/V ratio, the drug release is independent upon the shape of the tablets but it is only influenced by the S/V evolution. The model reveals itself able to describe the observed phenomena, and thus it can be of use for the design of oral drug delivery systems, even if complex shaped. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Building a roll-off roof or dome observatory a complete guide for design and construction

    CERN Document Server

    Hicks, John Stephen

    2016-01-01

    Almost every practical astronomer eventually aspires to have a fixed, permanent observatory for his or her telescope. A roll-off roof or dome observatory is the answer for the most popular home observatory design.  Almost every practical astronomer eventually aspires to have a fixed, permanent observatory for his or her telescope. A roll-off roof or dome observatory is the answer for the most popular home observatory design. Building a Roll-Off or Dome Observatory will help you decide whether to embark on the venture and will certainly increase your enthusiasm for the project. The author, both an amateur astronomer and a professional landscape architect, answers many of the common questions asked about observatory construction, covering the following topics: • Zoning, and by-law requirements common to most states, towns and municipalities • Where to locate the observatory • How to tailor the observatory for your particular needs • Tools and structural components required • Possible variations in de...

  6. Optimizing the night time with dome vents and SNR-QSO at CFHT

    Science.gov (United States)

    Devost, Daniel; Mahoney, Billy; Moutou, Claire; CFHT QSO Team, CFHT software Group

    2017-06-01

    Night time is a precious and costly commodity and it is important to get everything we can out of every second of every night of observing. In 2012 the Canada-France-Hawaii Telescope started operating 12 new vent doors installed on the dome over the course of the previous two years. The project was highly successful and seeing measurements show that venting the dome greatly enhances image quality at the focal plane. In order to capitalize on the gains brought by the new vents, the observatory started exploring a new mode of observation called SNR-QSO. This mode consist of a new implementation inside our Queued Service Observation (QSO) system. Exposure times are adjusted for each frame depending on the weather conditions in order to reach a specific depth, Signal to Noise Ratio (SNR) at a certain magnitude. The goal of this new mode is to capitalize on the exquisite seeing provided by Maunakea, complemented by the minimized dome turbulence, to use the least amount of time to reach the depth required by the science programs. Specific implementations were successfully tested on two different instruments, our wide field camera MegaCam and our high resolution spectrograph ESPaDOnS. I will present the methods used for each instrument to achieve SNR observing and the gains produced by these new observing modes in order to reach the scientific goals of accepted programs in a shorter amount of time.

  7. A preoperative mathematic model for computed tomographic guided microwave ablation treatment of hepatic dome tumors.

    Science.gov (United States)

    Gao, Fei; Wang, Guo-Bao; Xiang, Zhan-Wang; Yang, Bin; Xue, Jing-Bing; Mo, Zhi-Qiang; Zhong, Zhi-Hui; Zhang, Tao; Zhang, Fu-Jun; Fan, Wei-Jun

    2016-05-03

    This study sought to prospectively evaluate the feasibility and safety of a preoperative mathematic model for computed tomographic(CT) guided microwave(MW) ablation treatment of hepatic dome tumors. This mathematic model was a regular cylinder quantifying appropriate puncture routes from the bottom up. A total of 103 patients with hepatic dome tumors were enrolled and randomly divided into 2 groups based on whether this model was used or not: Group A (using the model; n = 43) versus Group B (not using the model; n = 60). All tumors were treated by CT-guided MW ablation and follow-up contrast CT were reviewed. The average number of times for successful puncture, average ablation time, and incidence of right shoulder pain were less in Group A than Group B (1.4 vs. 2.5, P = 0.001; 8.8 vs. 11.1 minutes, P = 0.003; and 4.7% vs. 20%, P = 0.039). The technical success rate was higher in Group A than Group B (97.7% vs. 85.0%, P = 0.032). There were no significant differences between the two groups in primary and secondary technique efficacy rates (97.7% vs. 88.3%, P = 0.081; 90.0% vs. 72.7%, P = 0.314). No major complications occurred in both groups. The mathematic model of regular cylinder is feasible and safe for CT-guided MW ablation in treating hepatic dome tumors.

  8. Development of Semi-Empirical Damping Equation for Baffled Tank with Oblate Spheroidal Dome

    Science.gov (United States)

    Yang, H. Q.; West, Jeff; Brodnick, Jacob; Eberhart, Chad

    2016-01-01

    Propellant slosh is a potential source of disturbance that can significantly impact the stability of space vehicles. The slosh dynamics are typically represented by a mechanical model of a spring-mass-damper. This mechanical model is then included in the equation of motion of the entire vehicle for Guidance, Navigation and Control analysis. The typical parameters required by the mechanical model include natural frequency of the slosh, slosh mass, slosh mass center location, and the critical damping ratio. A fundamental study has been undertaken at NASA MSFC to understand the fluid damping physics from a ring baffle in the barrel section of a propellant tank. An asymptotic damping equation and CFD blended equation have been derived by NASA MSFC team to complement the popularly used Miles equation at different flow regimes. The new development has found success in providing a nonlinear damping model for the Space Launch System. The purpose of this study is to further extend the semi-empirical damping equations into the oblate spheroidal dome section of the propellant tanks. First, previous experimental data from the spherical baffled tank are collected and analyzed. Several methods of taking the dome curvature effect, including a generalized Miles equation, area projection method, and equalized fill height method, are assessed. CFD simulation is used to shed light on the interaction of vorticity around the baffle with the locally curved wall and liquid-gas interface. The final damping equation will be validated by a recent subscale test with an oblate spheroidal dome conducted at NASA MSFC.

  9. Investigation of the utility of Gulf Coast salt domes for the storage or disposal of radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, J.D.; Thoms, R.L.; Kupfer, D.H.

    1976-09-30

    Analysis of tectonic, geohydrologic, and cultural data led to the selection of three salt domes (Vacherie, Rayburn's, Prothro) in the North Louisiana Basin and three (Keechi, Mt. Sylvan, Palestine) in the Northeast Texas Basin. Results of the tectonic stability studies (monitoring of dome movement, quaternary, Mesozoic and Tertiary, seismic, corehole in Vacherie) and hydrologic stability studies (numerical modeling, caprock, mine leaks) are discussed in detail and recommendations for further study are given. (DLC)

  10. Volcano-tectonic control of Merapi's lava dome splitting observed from high resolution TerraSAR-X data

    KAUST Repository

    Luehr, Birger-G.

    2015-04-01

    Volcanism at active andesite-dacite volcanoes is often associated with the formation and collapse of circular shaped protrusions of extruded, highly viscous lava, the so-called domes, which are emplaced in the near summit region. Growing domes may experience stable and instable structural phases, with a gradual transition in between. Dome collapse and the break-off of instable blocks of viscous lava may lead to pyroclastic flows, one of the most lethal hazards at stratovolcanoes. At Merapi volcano, Indonesia, nearly 50 % of all eruptions are accompanied by these phenomena. After the climactic eruption in 2010 which left an amphitheater in the summit region, a new dome started growing. Three years later, the dome reached a height of approximately 100 m and diameters of 220 and 190 m with a plateau-like surface area of 40,000m2 approximately. On 18/11/2013, an explosion occurred without identified precursors, leaving a major fracture cutting the complete dome structure. Based on high resolution TerraSAR-X satellite radar imagery, we could identify this linear fracture, traceable over ~200m in the long axis, and up to 40m width. After geocoding of the radar amplitude imagery, the fractures azimuthal trend could be compared to other structural lineaments, indicative of a significant NNW-SSE structural direction that has formed on Merapi volcano in the past. This alignment is also visible in a seismic velocity tomographic imagery for the upper crust, down to 15 km depth. The Merapi dome fractured in a NW-SE direction, and is consistent with the alignment of regional tectonic structures and of anticipated directions of pyroclastic flows. The fracture may be part of a larger volcano-tectonic system and may affect the dynamics and the stability of the Merapi dome.

  11. Design, construction and characterization of a rural solar furnace; Diseno, construccion y caracterizacion de un horno solar rural

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Luna, Gabriela

    2001-06-15

    centigrade, followed of the condition using 6 liters of oil, in which a maximum temperature of 115 centigrade was obtained and in the tests with 6 liters of water as load a maximum temperature of 95 centigrade was registered. In these tests the temperature of the oil surpasses 60 centigrade during an approximate period of 7 hours and is higher than 80 centigrade by a lapse of 5 hours. The water temperature is higher than 60 centigrade for a period of more than 5 hours and during 3 hours is higher than 80 centigrade. These results are satisfactory, because they assure the accomplishment of the process of baking inside the furnace. A calculation program was elaborated to implement the theoretical model of the concentration. This program reads the data of radiation intensity in the horizontal plane supplied by the weather station of the CIE and determines the incident radiation in the furnace collector. The theoretical model of the thermal behavior was implemented in another computer program; this program reads the data of the incident radiation in the collector of the furnace and the data of room temperature and calculates the temperature of the furnace as a time function. The model overestimates the temperature reached in the furnace, nevertheless reproduces qualitatively the thermal behavior of the same. In spite of the limitations of the theoretical model, this can be of utility in achieving the reproduction of the temperature of the load experimentally registered, through an effective coefficient of heat losses and an effective coefficient of heat capacity, characteristic of each one of the conditions of the test. [Spanish] Esta tesis presenta el diseno, construccion y caracterizacion de un horno solar tipo caja para su uso en comunidades rurales en la zona intertropical. El trabajo presentado en esta tesis parte del diseno opto-geometrico de un horno solar tipo caja propuesto por un entusiasta grupo de jovenes estudiantes (Acosta et al., 1996, Vazquez et al., 1998

  12. Determining Salinity by Simple Means.

    Science.gov (United States)

    Schlenker, Richard M.

    This paper describes the construction and use of a simple salinometer. The salinometer is composed, mainly, of a milliammeter and a battery and uses the measurement of current flow to determine the salinity of water. A complete list of materials is given, as are details of construction and operation of the equipment. The use of the salinometer in…

  13. Bulk Moisture and Salinity Sensor

    Science.gov (United States)

    Nurge, Mark; Monje, Oscar; Prenger, Jessica; Catechis, John

    2013-01-01

    Measurement and feedback control of nutrient solutions in plant root zones is critical to the development of healthy plants in both terrestrial and reduced-gravity environments. In addition to the water content, the amount of fertilizer in the nutrient solution is important to plant health. This typically requires a separate set of sensors to accomplish. A combination bulk moisture and salinity sensor has been designed, built, and tested with different nutrient solutions in several substrates. The substrates include glass beads, a clay-like substrate, and a nutrient-enriched substrate with the presence of plant roots. By measuring two key parameters, the sensor is able to monitor both the volumetric water content and salinity of the nutrient solution in bulk media. Many commercially available moisture sensors are point sensors, making localized measurements over a small volume at the point of insertion. Consequently, they are more prone to suffer from interferences with air bubbles, contact area of media, and root growth. This makes it difficult to get an accurate representation of true moisture content and distribution in the bulk media. Additionally, a network of point sensors is required, increasing the cabling, data acquisition, and calibration requirements. measure the dielectric properties of a material in the annular space of the vessel. Because the pore water in the media often has high salinity, a method to measure the media moisture content and salinity simultaneously was devised. Characterization of the frequency response for capacitance and conductance across the electrodes was completed for 2-mm glass bead media, 1- to 2-mm Turface (a clay like media), and 1- to 2-mm fertilized Turface with the presence of root mass. These measurements were then used to find empirical relationships among capacitance (C), the dissipation factor (D), the volumetric water content, and the pore water salinity.

  14. CARACTERIZACION VOZ Y VIDEO

    Directory of Open Access Journals (Sweden)

    Octavio José Salcedo Parra

    2011-11-01

    Full Text Available La motivación para caracterizar el tráfico de voz y video está en la necesidad de las empresas proveedoras de servicio en mantener redes de transporte de información con capacidades acordes a los requerimientos de los usuarios.  Poder determinar en forma oportuna como los elementos técnicos que hacen parte de las redes afectan su desempeño, teniendo en cuenta que cada tipo de servicio es afectado en mayor o menor medida por dichos elementos dentro de los que tenemos el jitter, las demoras y las pérdidas de paquetes entre otros. El presente trabajo muestra varios casos de caracterización de tráfico tanto de voz como de video en las que se utilizan una diversidad de técnicas para diferentes tipos de servicio.

  15. Blowing off steam: Tuffisite formation as a regulator for lava dome eruptions

    Directory of Open Access Journals (Sweden)

    Jackie Evan Kendrick

    2016-04-01

    Full Text Available Tuffisites are veins of variably sintered, pyroclastic particles that form in conduits and lava domes as a result of localized fragmentation events during gas-and-ash explosions. Those observed in-situ on the active 2012 lava dome of Volcán de Colima range from voids with intra-clasts showing little movement and interpreted to be failure-nuclei, to sub-parallel lenses of sintered granular aggregate interpreted as fragmentation horizons, through to infilled fractures with evidence of viscous remobilization. All tuffisites show evidence of sintering. Further examination of the complex fracture-and-channel patterns reveals viscous backfill by surrounding magma, suggesting that lava fragmentation was followed by stress relaxation and continued viscous deformation as the tuffisites formed. The natural tuffisites are more permeable than the host andesite, and have a wide range of porosity and permeability compared to a narrower window for the host rock, and gauging from their significant distribution across the dome, we posit that the tuffisite veins may act as important outgassing pathways. To investigate tuffisite formation we crushed and sieved andesite from the lava dome and sintered it at magmatic temperatures for different times. We then assessed the healing and sealing ability by measuring porosity and permeability, showing that sintering reduces both over time. During sintering the porosity-permeability reduction occurs due to the formation of viscous necks between adjacent grains, a process described by the neck-formation model of Frenkel (1945. This process leads the granular starting material to a porosity-permeability regime anticipated for effusive lavas, and which describes the natural host lava as well as the most impervious of natural tuffisites. This suggests that tuffisite formation at Volcán de Colima constructed a permeable network that enabled gas to bleed passively from the magma. We postulate that this progressively reduced

  16. Development of Core Complex Domes Due to Along-Axis Variation in Diking

    Science.gov (United States)

    Buck, W. R.; Choi, E.; Tian, X.

    2014-12-01

    Continental and oceanic core complexes are characterized by fairly smooth, unfaulted, but corrugated surfaces of high grade rocks often domed both along and orthogonal to the transport direction. The corrugations, or mega-mullions, are remarkably continuous in the transport direction and may be tens of kilometers long. Spencer [1999] suggests that corrugations with across-transport wavelengths of millimeter to ~25 km scales are formed when the lower plate of a large-offset normal fault is "continuously cast," as warm, ductile mantle and gabbro is pulled up against the cooler upper plate. Continuous casting is widely accepted as a mechanism to form the shorter wavelength corrugations as a result of irregularities of the brittle upper plate surface. However, doming is generally ascribed to upflow of buoyant diapirs or transtensional deformation of the lithosphere. We suggest that doming of core complexes can be a product of continuous casting when a large-offset fault evolves to be curved in plan-view. For oceanic core complexes along-axis variation in magmatism can lead to lateral offset of a detachment fault relative to the spreading axis. We assume that near-ridge normal faults form relatively straight and consider that horizontal offsets in the along-axis position of a large-offset fault (or detachment) result from variations in the rate of magmatic diking. Assuming a sinusoidal variation in the rate of dike opening with distance along the axis the evolution of fault offset and the plan-view shape of the active fault is easy to describe. Because the fault length increases as it is offset, the work to slip on the fault increases with time. Eventually, it should be easier to slip in a new straight fault and the conditions for this can be described with an approximate analytic model. We are developing 3D numerical models to test the predictions of this analytic model and show how the topographic amplitude of the domes depends the fault dip, the amplitude of the

  17. The Chaitén rhyolite lava dome: Eruption sequence, lava dome volumes, rapid effusion rates and source of the rhyolite magma

    Science.gov (United States)

    Pallister, John S.; Diefenbach, Angela K.; Burton, William C.; Munoz, Jorge; Griswold, Julia P.; Lara, Luis E.; Lowenstern, Jacob B.; Valenzuela, Carolina E.

    2013-01-01

    We use geologic field mapping and sampling, photogrammetric analysis of oblique aerial photographs, and digital elevation models to document the 2008-2009 eruptive sequence at Chaitén Volcano and to estimate volumes and effusion rates for the lava dome. We also present geochemical and petrologic data that contribute to understanding the source of the rhyolite and its unusually rapid effusion rates. The eruption consisted of five major phases: 1. An explosive phase (1-11 May 2008); 2. A transitional phase (11-31 May 2008) in which low-altitude tephra columns and simultaneous lava extrusion took place; 3. An exogenous lava flow phase (June-September 2008); 4. A spine extrusion and endogenous growth phase (October 2008-February 2009); and 5. A mainly endogenous growth phase that began after the collapse of a prominent Peléean spine on 19 February 2009 and continued until the end of the eruption (late 2009 or possibly earliest 2010). The 2008-2009 rhyolite lava dome has a total volume of approximately 0.8 km3. The effusion rate averaged 66 m3s-1 during the first two weeks and averaged 45 m3s-1 for the first four months of the eruption, during which 0.5 km3 of rhyolite lava was erupted. These are among the highest rates measured world-wide for historical eruptions of silicic lava. Chaitén’s 2008-2009 lava is phenocryst-poor obsidian and microcrystalline rhyolite with 75.3±0.3% SiO2. The lava was erupted at relatively high temperature and is remarkably similar in composition and petrography to Chaitén’s pre-historic rhyolite. The rhyolite’s normative composition plots close to that of low pressure (100-200 MPa) minimum melts in the granite system, consistent with estimates of approximately 5 to 10 km source depths based on phase equilibria and geodetic studies. Calcic plagioclase, magnesian orthopyroxene and aluminous amphibole among the sparse phenocrysts suggest derivation of the rhyolite by melt extraction from a more mafic magmatic mush. High temperature

  18. Assessment of Effectiveness of Geologic Isolation Systems: REFERENCE SITE INITIAL ASSESSMENT FOR A SALT DOME REPOSITORY

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, M. A.; Brandstetter, A.; Benson, G. L.; Raymond, J. R.; Brandley, D. J.; Serne, R. J.; Soldat, J. K.; Cole, C. R.; Deutsch, W. J.; Gupta, S. K.; Harwell, C. C.; Napier, B. A.; Reisenauer, A. E.; Prater, L. S.; Simmons, C. S.; Strenge, D. L.; Washburn, J. F.; Zellmer, J. T.

    1982-06-01

    As a methodology demonstration for the Office of Nuclear Waste Isolation (ONWI), the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program conducted an initial reference site analysis of the long-term effectiveness of a salt dome repository. The Hainesville Salt Dome in Texas was chosen to be representative of the Gulf Coast interior salt domes; however, the Hainesville Site has been eliminated as a possible nuclear waste repository site. The data used for this exercise are not adequate for an actual assessment, nor have all the parametric analyses been made that would adequately characterize the response of the geosystem surrounding the repository. Additionally, because this was the first exercise of the complete AEGIS and WASTE Rock Interaction Technology (WRIT) methodology, this report provides the initial opportunity for the methodology, specifically applied to a site, to be reviewed by the community outside the AEGIS. The scenario evaluation, as a part of the methodology demonstration, involved consideration of a large variety of potentially disruptive phenomena, which alone or in concert could lead to a breach in a salt dome repository and to a subsequent transport of the radionuclides to the environment. Without waste- and repository-induced effects, no plausible natural geologic events or processes which would compromise the repository integrity could be envisioned over the one-million-year time frame after closure. Near-field (waste- and repository-induced) effects were excluded from consideration in this analysis, but they can be added in future analyses when that methodology development is more complete. The potential for consequential human intrusion into salt domes within a million-year time frame led to the consideration of a solution mining intrusion scenario. The AEGIS staff developed a specific human intrusion scenario at 100 years and 1000 years post-closure, which is one of a whole suite of possible scenarios. This scenario

  19. Assessment of Effectiveness of Geologic Isolation Systems: REFERENCE SITE INITIAL ASSESSMENT FOR A SALT DOME REPOSITORY

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, M. A.; Brandstetter, A.; Benson, G. L.; Bradley, D. J.; Serne, R. J.; Soldat, J. K; Cole, C. R.; Deutsch, W. J.; Gupta, S. K.; Harwell, C. C.; Napier, B. A.; Reisenauer, A. E.; Prater, L. S.; Simmons, C. S.; Strenge, D. L.; Washburn, J. F.; Zellmer, J. T.

    1982-06-01

    As a methodology demonstration for the Office of Nuclear Waste Isolation (ONWI), the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program conducted an initial reference site analysis of the long-term effectiveness of a salt dome repository. The Hainesville Salt Dome in Texas was chosen to be representative of the Gulf Coast interior salt domes; however, the Hainesville Site has been eliminated as a possible nuclear waste repository site. The data used for this exercise are not adequate for an actual assessment, nor have all the parametric analyses been made that would adequately characterize the response of the geosystem surrounding the repository. Additionally, because this was the first exercise of the complete AEGIS and WASTE Rock Interaction Technology (WRIT) methodology, this report provides the initial opportunity for the methodology, specifically applied to a site, to be reviewed by the community outside the AEGIS. The scenario evaluation, as a part of the methodology demonstration, involved consideration of a large variety of potentially disruptive phenomena, which alone or in concert could lead to a breach in a salt dome repository and to a subsequent transport of the radionuclides to the environment. Without waste- and repository-induced effects, no plausible natural geologic events or processes which would compromise the repository integrity could be envisioned over the one-million-year time frame after closure. Near-field (waste- and repository-induced) effects were excluded from consideration in this analysis, but they can be added in future analyses when that methodology development is more complete. The potential for consequential human intrusion into salt domes within a million-year time frame led to the consideration of a solution mining intrusion scenario. The AEGIS staff developed a specific human intrusion scenario at 100 years and 1000 years post-closure, which is one of a whole suite of possible scenarios. This scenario

  20. Gneiss domes of the Danba Metamorphic Complex, Songpan Ganze, eastern Tibet

    Science.gov (United States)

    Billerot, Audrey; Duchene, Stéphanie; Vanderhaeghe, Olivier; de Sigoyer, Julia

    2017-06-01

    In this paper we address the formation and exhumation of the Danba Metamorphic Complex (DMC) that represents the deepest structural level of the Songpan Ganze terrane situated along the eastern margin of the Tibetan plateau. The DMC comprises a variety of gneiss domes and offers a unique opportunity to decipher their development during orogenic evolution. For that purpose, PTtD paths of metamorphic rocks sampled at different structural levels have been reconstructed. The DMC is composed of Triassic metaturbidites of the Xikang group, Paleozoic metasedimentary cover and basement of the Yangtze craton. The DMC is structurally marked by transposition of the upright S1 foliation of the Triassic metaturbidites into a NW-SE trending S2 composite foliation dipping to the NE. Transposition is associated with a localized top-to-the-northeast shear zone along the northeastern edge of the DMC and with pervasive top-to-the-southwest shearing from the core to the border of the complex. These structures are consistent with extrusion of the core of the DMC relative to the lower grade Triassic metaturbidites. The position of the biotite isograd overlapping the structural boundary of the DMC suggests that the Triassic metaturbidites have been affected by an increase in temperature as a result of extrusion. Within the DMC, the position of the metamorphic index minerals relative to the composite S2 foliation reveals that biotite, garnet, staurolite and kyanite grew before the transposition into S2, in contrast with sillimanite which crystallizes in the hinge of F2 folds and along the axial planar S2 schistosity. The sillimanite isograd delineates regional-scale overturned F2 folds and cross-cuts the staurolite and kyanite isograds consistent with an increase in temperature during D2. The melt-in isograd characterizes the deepest structural level of the DMC. PT conditions for these metamorphic rocks, determined using pseudosections and conventional thermometry, indicate a temperature

  1. The Sequential Emplacement of the Chaos Crags Dome Complex in Lassen National Park and a Subsequent Avalanche Event Revealing the Internal Structure of a Crystal-Rich Lava Dome

    Science.gov (United States)

    Watts, R. B.; Clynne, M. A.; Sparks, R. S.; Christiansen, R. L.

    2013-12-01

    The Chaos Crags are an aptly named and spectacularly well-preserved nest of 6 crystal-rich rhyodacitic lava domes that lie in the shadow of the renowned Lassen Peak in Lassen National Park, northern California. Each of the domes is composed of a precarious pile of large angular lava blocks indicative of a relatively fast extrusion rate. However, the 2 southernmost domes (i.e. Group 1) exhibit a coulée-like appearance with asymmetric appearance, a thick, glassy basal breccia and distinct concentric flow ridges on the upper surface. The 4 northernmost domes (i.e. Group 2) are notably more dome-like, lacking lateral flow-features and any basal breccia but displaying steeper, blocky flanks and overall low Aspect Ratio. Petrologically, the 2 Groups are very similar in whole-rock composition except there is a distinct difference in the amount of mafic inclusions present - that is ~2 vol% (Group1 domes) and ~10vol% (Group 2 domes). The age of emplacement of the Crags has been previously determined as between 1125 and 375 years B.P (Clynne & Muffler, 1989). Following a period of quiescence, a series of 3 rock-fall avalanches, most likely triggered by a tectonic earthquake, collapsed away from one of the Group 2 domes to produce the 'Jumbles Avalanche' deposit. This impressive deposit (total volume of ~7km2) spilled across the northeastern landscape focused away from the base of Dome C, one of the Group 2 domes. The avalanche events left behind a near-vertical scarp composed of shattered, massive lava riddled with closely-spaced sigmoidal cooling joints to produce a very unstable ~250 meter high and ~300 meter wide metastable structure. On its upper surface, the remnants of a smooth semi-cylindical surface scored with striations is evident. Sampling from this surface and other points away from this surface highlighted the presence of highly fragmented lava with broken jigsaw-style phenocrysts up to one meter away from the smooth surface. Samples taken from a larger

  2. Salinity: Electrical conductivity and total dissolved solids

    Science.gov (United States)

    The measurement of soil salinity is a quantification of the total salts present in the liquid portion of the soil. Soil salinity is important in agriculture because salinity reduces crop yields by reducing the osmotic potential making it more difficult for the plant to extract water, by causing spe...

  3. Stochastic modeling of soil salinity

    Science.gov (United States)

    Suweis, S.; Porporato, A. M.; Daly, E.; van der Zee, S.; Maritan, A.; Rinaldo, A.

    2010-12-01

    A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The equations for the probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equations to a single stochastic differential equation (generalized Langevin equation) driven by multiplicative Poisson noise. Generalized Langevin equations with multiplicative white Poisson noise pose the usual Ito (I) or Stratonovich (S) prescription dilemma. Different interpretations lead to different results and then choosing between the I and S prescriptions is crucial to describe correctly the dynamics of the model systems. We show how this choice can be determined by physical information about the timescales involved in the process. We also show that when the multiplicative noise is at most linear in the random variable one prescription can be made equivalent to the other by a suitable transformation in the jump probability distribution. We then apply these results to the generalized Langevin equation that drives the salt mass dynamics. The stationary analytical solutions for the probability density functions of salt mass and concentration provide insight on the interplay of the main soil, plant and climate parameters responsible for long term soil salinization. In particular, they show the existence of two distinct regimes, one where the mean salt mass remains nearly constant (or decreases) with increasing rainfall frequency, and another where mean salt content increases markedly with increasing rainfall frequency. As a result, relatively small reductions of rainfall in drier climates may entail dramatic shifts in longterm soil salinization trends, with significant consequences, e.g. for climate change impacts on rain fed agriculture.

  4. The Aquarius Salinity Retrieval Algorithm

    Science.gov (United States)

    Meissner, Thomas; Wentz, Frank; Hilburn, Kyle; Lagerloef, Gary; Le Vine, David

    2012-01-01

    The first part of this presentation gives an overview over the Aquarius salinity retrieval algorithm. The instrument calibration [2] converts Aquarius radiometer counts into antenna temperatures (TA). The salinity retrieval algorithm converts those TA into brightness temperatures (TB) at a flat ocean surface. As a first step, contributions arising from the intrusion of solar, lunar and galactic radiation are subtracted. The antenna pattern correction (APC) removes the effects of cross-polarization contamination and spillover. The Aquarius radiometer measures the 3rd Stokes parameter in addition to vertical (v) and horizontal (h) polarizations, which allows for an easy removal of ionospheric Faraday rotation. The atmospheric absorption at L-band is almost entirely due to molecular oxygen, which can be calculated based on auxiliary input fields from numerical weather prediction models and then successively removed from the TB. The final step in the TA to TB conversion is the correction for the roughness of the sea surface due to wind, which is addressed in more detail in section 3. The TB of the flat ocean surface can now be matched to a salinity value using a surface emission model that is based on a model for the dielectric constant of sea water [3], [4] and an auxiliary field for the sea surface temperature. In the current processing only v-pol TB are used for this last step.

  5. High-directional light source using photon recycling with a retro-reflective Dome incorporated with a textured LED die surface.

    Science.gov (United States)

    Sun, Ching-Cherng; Chung, Shuang-Chao; Yang, Shuang-Hao; Yu, Yeh-Wei; Chien, Wei-Ting; Chen, Huang-Kuen; Chen, Shih-Peng

    2013-07-29

    This paper demonstrates a novel retro-reflective dome that enhances the directionality of a light emitting diode (LED) by recycling photons reflected by a textured LED die surface. A simulation model is developed to describe both the photon recycling process within the dome and the role of specific pyramid patterns on the top surface of the LED die. Advanced simulations showed that a perfectly polished surface with 100% reflectivity potentially enhances the directionality of the dome by 340%, 250%, and 240% using reflective domes with 10°, 20°, and 30° light cones, respectively. In the experiment, the directionality of the domes exhibiting surface imperfections is enhanced by approximately 160%, 150%, and 130% using 10°, 20°, and 30° light cones, respectively. By incorporating a textured top surface on the LED die, the proposed dome effectively increases the directionality of the LED light source.

  6. Strategic Petroleum Reserve (SPR) additional geologic site characterization studies, Bryan Mound Salt Dome, Texas

    Energy Technology Data Exchange (ETDEWEB)

    Neal, J.T. [Sandia National Labs., Albuquerque, NM (United States); Magorian, T.R.; Ahmad, S. [Acres International Corp., Amherst, NY (United States)

    1994-11-01

    This report revises the original report that was published in 1980. Some of the topics covered in the earlier report were provisional and it is now practicable to reexamine them using new or revised geotechnical data and that obtained from SPR cavern operations, which involves 16 new caverns. Revised structure maps and sections show interpretative differences as compared with the 1980 report and more definition in the dome shape and caprock structural contours, especially a major southeast-northwest trending anomalous zone. The original interpretation was of westward tilt of the dome, this revision shows a tilt to the southeast, consistent with other gravity and seismic data. This interpretation refines the evaluation of additional cavern space, by adding more salt buffer and allowing several more caverns. Additional storage space is constrained on this nearly full dome because of low-lying peripheral wetlands, but 60 MMBBL or more of additional volume could be gained in six or more new caverns. Subsidence values at Bryan Mound are among the lowest in the SPR system, averaging about 11 mm/yr (0.4 in/yr), but measurement and interpretation issues persist, as observed values are about the same as survey measurement accuracy. Periodic flooding is a continuing threat because of the coastal proximity and because peripheral portions of the site are at elevations less than 15 ft. This threat may increase slightly as future subsidence lowers the surface, but the amount is apt to be small. Caprock integrity may be affected by structural features, especially the faulting associated with anomalous zones. Injection wells have not been used extensively at Bryan Mound, but could be a practicable solution to future brine disposal needs. Environmental issues center on the areas of low elevation that are below 15 feet above mean sea level: the coastal proximity and lowland environment combined with the potential for flooding create conditions that require continuing surveillance.

  7. Late Cenozoic extension and crustal doming in the NE Chinese Pamir

    Science.gov (United States)

    Thiede, Rasmus C.; Sobel, Edward R.; Chen, Jie; Schoenbohm, Lindsay; Stockli, Daniel; Sudo, Masafumi; Strecker, Manfred

    2013-04-01

    The northward motion of the Pamir indenter with respect to Eurasia has resulted in coeval thrusting, strike-slip and normal faulting. The eastern Pamir is currently deformed by east-west oriented extension, accompanied by uplift and exhumation of the Kongur Shan (7719 m) and Muztagh Ata (7546 m) gneiss domes. Both domes are an integral part of the footwall of the Kongur Shan Extensional System (KES), a 250-km-long, north-south oriented graben. Why active normal faulting within the Pamir is primarily localized along the KES and not distributed more widely throughout the orogen, has remained unclear. In addition, relatively little is known about how deformation has evolved throughout the Cenozoic, despite refined estimates on present-day crustal deformation rates and microseismicity, which indicate where crustal deformation is presently being accommodated. To better constrain the spatiotemporal evolution of faulting along the KES, we present 39 new apatite fission-track, zircon U-Th-Sm/He, and 40Ar/39Ar cooling ages from a series of footwall transects along the KES graben shoulder. Combining this data with, present day topographic relief, 1D thermo-kinematic and exhumational modeling documents successive stages, rather than synchronous deformation and gneiss dome exhumation. While Kongur-Shan-exhumation started during the late Miocene, Muztagh Ata began earlier and has slowed down since the late Miocene. We present a new model, suggesting that thermal and density effects associated with a lithospheric tear fault along the eastern margin of the subducting Alai slab localizes extensional upper-plate deformation along the KES and decouples crustal motion between the Central/Western Pamir and Eastern Pamir/Tarim basin.

  8. Dome collapse eruption in Tatun Volcanic Group near metropolitan Taipei, Taiwan at ~6 kyrs

    Science.gov (United States)

    Chen, C.; Lee, T.

    2010-12-01

    The Tatun Volcanic Group (TVG) is located in the north of metropolitan Taipei, Taiwan. Over 6 million inhabitants are living in Taipei City and suburban area. Another critical issue is an international airport and two nuclear power plants are lying at the foot of the TVG. If the TGV will be re-active, the serious hazard for human lives and economies in this area will definitely occur. Understanding the youngest eruption history of the TVG will be much important for prediction the future activity of eruption. The core was collected from the Dream Lake at the eastern slop of Cising Mt.. Total 21 samples from depth 190 cm to 231.5 cm have been tested. Comparison of chemical compositions of glass and minerals in the volcanic clasts with those of lava around TVG, they clearly showed that the volcanic clasts can be correlated with the eruption of the closest Cising Mt. According to the radiocarbon (C-14) age of core sample at the depth 225 cm, the age was extrapolated around 6150 yrs ca. C-14 B.P.. Moreover, the respiratory cristobalite in the volcanic clasts were firstly identified by the identical morphology, chemical composition and Laser Raman Spectrometry (LRS). The crystalline silica was produced by vapor-phase crystallization and devitrification in the andesite lava dome and volcanic ash generated by pyroclastic flows formed by lava dome collapse in Soufriere Hills volcano, Montserrat (Baxter et al.,1999). These new evidence demonstrated that there would probably have the lava dome collapse eruptions in the TVG in the last 6 kyrs. The result in this paper also sustained that the landslide caused by the weak phreatic eruption within the last 6000 yrs in the TVG (Belousov et al., 2010). It must further be noted that an efficient program of the volcanic hazard reduction should be practiced for the metropolitan Taipei and suburban area.

  9. Seasonal cycle and modal structure of particle number size distribution at Dome C, Antarctica

    Directory of Open Access Journals (Sweden)

    E. Järvinen

    2013-08-01

    Full Text Available We studied new particle formation and modal behavior of ultrafine aerosol particles on the high East Antarctic plateau at the Concordia station, Dome C (75°06' S, 123°23' E. Aerosol particle number size distributions were measured in the size range 10–600 nm from 14 December 2007 to 7 November 2009. We used an automatic algorithm for fitting up to three modes to the size distribution data. The total particle number concentration was low with the median of 109 cm−3. There was a clear seasonal cycle in the total particle number and the volume concentrations. The concentrations were at their highest during the austral summer with the median values of 260 cm−3 and 0.086 μm3 cm−3, and at their lowest during the austral winter with corresponding values of 15 cm−3 and 0.009 μm3 cm−3. New particle formation events were determined from the size distribution data. During the measurement period, natural new particle formation was observed on 60 days and for 15 of these days the particle growth rates from 10 to 25 nm in size could be determined. The median particle growth rate during all these events was 2.5 nm h−1 and the median formation rate of 10 nm particles was 0.023 cm−3 s−1. Most of the events were similar to those observed at other continental locations, yet also some variability in event types was observed. Exceptional features in Dome C were the winter events that occurred during dark periods, as well as the events for which the growth could be followed during several consecutive days. We called these latter events slowly growing events. This paper is the first one to analyze long-term size distribution data from Dome C, and also the first paper to show that new particle formation events occur in central Antarctica.

  10. Strategic Petroleum Reserve (SPR) additional geologic site characterization studies, Bayou Choctaw salt dome, Louisiana

    Energy Technology Data Exchange (ETDEWEB)

    Neal, J.T. [Sandia National Labs., Albuquerque, NM (United States); Magorian, T.R. [Magorian (Thomas R.), Amherst, NY (United States); Byrne, K.O.; Denzler, S. [Acres International Corp., Amherst, NY (United States)

    1993-09-01

    This report revises and updates the geologic site characterization report that was published in 1980. Revised structure maps and sections show interpretative differences in the dome shape and caprock structural contours, especially a major east-west trending shear zone, not mapped in the 1980 report. Excessive gas influx in Caverns 18 and 20 may be associated with this shear zone. Subsidence values at Bayou Choctaw are among the lowest in the SPR system, averaging only about 10 mm/yr but measurement and interpretation issues persist, as observed values often approximate measurement accuracy. Periodic, temporary flooding is a continuing concern because of the low site elevation (less than 10 ft), and this may intensify as future subsidence lowers the surface even further. Cavern 4 was re-sonared in 1992 and the profiles suggest that significant change has not occurred since 1980, thereby reducing the uncertainty of possible overburden collapse -- as occurred at Cavern 7 in 1954. Other potential integrity issues persist, such as the proximity of Cavern 20 to the dome edge, and the narrow web separating Caverns 15 and 17. Injection wells have been used for the disposal of brine but have been only marginally effective thus far; recompletions into more permeable lower Pleistocene gravels may be a practical way of increasing injection capacity and brinefield efficiency. Cavern storage space is limited on this already crowded dome, but 15 MMBBL could be gained by enlarging Cavern 19 and by constructing a new cavern beneath and slightly north of abandoned Cavern 13. Environmental issues center on the low site elevation: the backswamp environment combined with the potential for periodic flooding create conditions that will require continuing surveillance.

  11. Single-incision laparoscopic cholecystectomy using a modified dome-down approach with conventional laparoscopic instruments.

    Science.gov (United States)

    Cui, Hongyi; Kelly, John J; Litwin, Demetrius E M

    2012-04-01

    Single-incision laparoscopic cholecystectomy (SILC) may increase the risk of bile duct injury due to compromised operative exposure. Dome-down laparoscopic cholecystectomy provides the ability to evaluate the cystic duct circumferentially prior to its division, thus minimizing the risks of bile duct injury. This study assesses the feasibility and safety of SILC using a modified dome-down approach with all conventional laparoscopic instruments. Three low-profile 5-mm trocars are placed via a single transumbilical incision. The two working trocars are aimed laterally via the rectus to achieve adequate triangulation. An extralong 5-mm 30º laparoscope with an L-shaped light-cord adaptor is used to yield more external working space. Cephalic liver retraction is achieved with one transabdominal suture through the gallbladder fundus. Leaving the gallbladder fundus attached to the liver bed, a window is first created between the gallbladder body and the liver. The dissection is then carried down retrograde toward the porta hepatis. A 360º view of the gallbladder-cystic duct junction is achieved prior to transecting the cystic duct. The gallbladder is then freed by separation of the fundal attachments. The specimen is retrieved by enlarging the fascial incision. All fascial defects are then primarily closed. Sixteen patients (mean age 31 years, mean BMI 26.3 kg/m(2)) were enrolled in this study. Thirteen had elective surgery for symptomatic cholelithiasis, and three had emergency surgery for acute cholecystitis. Mean operating time was 80.3 min, and blood loss was minimal. All patients were discharged within 24 h without complications. Follow-up at 1 month revealed a barely visible scar within the umbilicus. SILC using a modified dome-down approach is technically feasible with all straight instruments, and it is safe because of good delineation of ductal anatomy. Adoption of this approach may minimize the risk of bile duct injury during early experience of SILC.

  12. Hydrogeologic processes in saline systems: Playas, sabkhas, and saline lakes

    Science.gov (United States)

    Yechieli, Y.; Wood, W.W.

    2002-01-01

    Pans, playas, sabkhas, salinas, saline lakes, and salt flats are hydrologically similar, varying only in their boundary conditions. Thus, in evaluating geochemical processes in these systems, a generic water and solute mass-balance approach can be utilized. A conceptual model of a coastal sabkha near the Arabian Gulf is used as an example to illustrate the various water and solute fluxes. Analysis of this model suggests that upward flux of ground water from underlying formations could be a major source of solutes in the sabkha, but contribute only a small volume of the water. Local rainfall is the main source of water in the modeled sabkha system with a surprisingly large recharge-to-rainfall ratio of more than 50%. The contribution of seawater to the solute budget depends on the ratio of the width of the supratidal zone to the total width and is generally confined to a narrow zone near the shoreline of a typical coastal sabkha. Because of a short residence time of water, steady-state flow is expected within a short time (50,000 years). The solute composition of the brine in a closed saline system depends largely on the original composition of the input water. The high total ion content in the brine limits the efficiency of water-rock interaction and absorption. Because most natural systems are hydrologically open, the chemistry of the brines and the associated evaporite deposits may be significantly different than that predicted for hydrologically closed systems. Seasonal changes in temperature of the unsaturated zone cause precipitation of minerals in saline systems undergoing evaporation. Thus, during the hot dry season months, minerals exhibit retrograde solubility so that gypsum, anhydrite and calcite precipitate. Evaporation near the surface is also a major process that causes mineral precipitation in the upper portion of the unsaturated zone (e.g. halite and carnallite), provided that the relative humidity of the atmosphere is less than the activity of water

  13. Simulated Service and Stress Corrosion Cracking Testing for Friction Stir Welded Spun Form Domes

    Science.gov (United States)

    Stewart, Thomas J.; Torres, Pablo D.; Caratus, Andrei A.; Curreri, Peter A.

    2010-01-01

    Damage tolerance testing development was required to help qualify a new spin forming dome fabrication process for the Ares 1 program at Marshall Space Flight Center (MSFC). One challenge of the testing was due to the compound curvature of the dome. The testing was developed on a sub-scale dome with a diameter of approximately 40 inches. The simulated service testing performed was based on the EQTP1102 Rev L 2195 Aluminum Lot Acceptance Simulated Service Test and Analysis Procedure generated by Lockheed Martin for the Space Shuttle External Fuel Tank. This testing is performed on a specimen with an induced flaw of elliptical shape generated by Electrical Discharge Machining (EDM) and subsequent fatigue cycling for crack propagation to a predetermined length and depth. The specimen is then loaded in tension at a constant rate of displacement at room temperature until fracture occurs while recording load and strain. An identical specimen with a similar flaw is then proof tested at room temperature to imminent failure based on the critical offset strain achieved by the previous fracture test. If the specimen survives the proof, it is then subjected to cryogenic cycling with loads that are a percentage of the proof load performed at room temperature. If all cryogenic cycles are successful, the specimen is loaded in tension to failure at the end of the test. This standard was generated for flat plate, so a method of translating this to a specimen of compound curvature was required. This was accomplished by fabricating a fixture that maintained the curvature of the specimen rigidly with the exception of approximately one-half inch in the center of the specimen containing the induced flaw. This in conjunction with placing the center of the specimen in the center of the load train allowed for successful testing with a minimal amount of bending introduced into the system. Stress corrosion cracking (SCC) tests were performed using the typical double beam assembly and with 4

  14. Component and prototype panel testing of the mini-dome Fresnel lens photovoltaic concentrator array

    Science.gov (United States)

    Piszczor, Michael F.; Swartz, Clifford K.; O'Neill, Mark J.

    1990-01-01

    The mini-dome Fresnel lens concentrator array, a high-efficiency, lightweight space photovoltaic array concept, is described. The three critical elements of the array concept are the Fresnel lens concentrator, the prismatic cell power cover, and the photovoltaic cell. Prototype concentrator lenses have been fabricated and tested, with optical efficiencies reaching 90 percent. Work is progressing on the design and fabrication of the panel structure. The impact of recent advances in 30 percent-efficient multijunction photovoltaic cells on array performance is also discussed. Near-term performance goals of 300 w/sq m and 100 w/kg are now feasible.

  15. Integrated, multi-parameter, investigation of eruptive dynamics at Santiaguito lava dome, Guatemala

    Science.gov (United States)

    Lavallée, Yan; De Angelis, Silvio; Rietbrock, Andreas; Lamb, Oliver; Hornby, Adrian; Lamur, Anthony; Kendrick, Jackie E.; von Aulock, Felix W.; Chigna, Gustavo

    2016-04-01

    Understanding the nature of the signals generated at volcanoes is central to hazard mitigation efforts. Systematic identification and understanding of the processes responsible for the signals associated with volcanic activity are only possible when high-resolution data are available over relatively long periods of time. For this reason, in November 2014, the Liverpool Earth Observatory (LEO), UK, in collaboration with colleagues of the Instituto Nacional de Sismologia, Meteorologia e Hidrologia (INSIVUMEH), Guatemala, installed a large multi-parameter geophysical monitoring network at Santiaguito - the most active volcano in Guatemala. The network, which is to date the largest temporary deployment on Santiaguito, includes nine three-component broadband seismometers, three tiltmeters, and five infrasound microphones. Further, during the initial installation campaign we conducted visual and thermal infrared measurements of surface explosive activity and collected numerous rock samples for geochemical, geophysical and rheological characterisation. Activity at Santiaguito began in 1922, with the extrusion of a series of lava domes. In recent years, persistent dome extrusion has yielded spectacularly episodic piston-like motion displayed by characteristic tilt/seismic patterns (Johnson et al, 2014). This cyclicity episodically concludes with gas emissions or gas-and-ash explosions, observed to progress along a complex fault system in the dome. The explosive activity is associated with distinct geophysical signals characterised by the presence of very-long period earthquakes as well as more rapid inflation/deflation cycles; the erupted ash further evidences partial melting and thermal vesiculation resulting from fault processes (Lavallée et al., 2015). One year of data demonstrates the regularity of the periodicity and intensity of the explosions; analysis of infrasound data suggests that each explosion expulses on the order of 10,000-100,000 kg of gas and ash. We

  16. Structural and thermal evolution of Northwest Thor-Odin dome, Monashee complex, southeast British Columbia

    Science.gov (United States)

    Johnston, Dennis Hugh

    Thor-Odin and Frenchman Cap, two antiformal culminations of high-grade metamorphic rock, comprise the Monashee complex in southeast British Columbia. A kilometre-thick NE-directed ductile thrust, the Monashee decollement, previously mapped at Frenchman Cap and inferred at Cariboo Alp at the southwest margin of the Thor-Odin dome, locally separates the Monashee complex (MC) from the overlying Selkirk allochthon (SA). In the area studied along the west flank of the Thor-Odin dome, there is no decollement exposed: NE-directed shear was distributed throughout the culmination (4--5 kilornetre thickness exposed) rather than being confined to a discrete zone. Rocks in the study area are thoroughly transposed (into S2). The extent of the transposition, and a well-developed northeasterly-trending L2 mineral lineation, indicate intense strain during F1/F 2. Penetrative northeastward ductile flow parallel to the transposition foliation continued in the Thor-Odin dome, resulting in NE-verging F 3 folds and NE-directed D3 fabrics. At the highest structural levels farther west, in the SA, F3 folds are W-SW-verging (e.g., Joss Mountain fold nappe). Along the west flank of the Thor-Odin dome, in the Greenbush Lake shear band zone (GLSBZ), L2 was rotated to a west-southwest trend, folds were truncated and abundant mesoscopic W-SW-dipping top-to-W-SW shear bands formed as a result of D5 reactivated slip on S2. There is a marked hiatus in U-Pb monazite ages between the SA (ca. 94--84 Ma, Joss Mountain) and the MC (ca. 55--57 Ma, Blanket Mountain). Along the studied west flank of the MC, a narrow zone of well-preserved kyanite is bounded above and below by zones in which kyanite has been pseudornorphously replaced by sillimanite. Kyanite does not occur in higher structural levels of the MC or in the overlying SA. Northeasterly flow during F1/F2 developed in response to westward underplating of North American basement (e.g., MC) and its sedimentary cover beneath the hinterland

  17. Approach to the E-ELT dome and main structure challenges

    Science.gov (United States)

    Bilbao, Armando; Murga, Gaizka; Gómez, Celia; Llarena, Javier

    2014-07-01

    The E-ELT as a whole could be classified as an extremely challenging project. More precisely, it should be defined as an array of many different sub-challenges, which comprise technical, logistical and managerial matters. This paper reviews some of these critical challenges, in particular those related to the Dome and the Main Structure, suggesting ways to face them in the most pragmatic way possible. Technical challenges for the Dome and the Main Structure are mainly related to the need to upscale current design standards to an order of magnitude larger design. Trying a direct design escalation is not feasible; it would not work. A design effort is needed to cross hybridize current design standards with technologies coming from other different applications. Innovative design is therefore not a wish but a must. And innovative design comes along with design risk. Design risk needs to be tackled from two angles: on the one hand through thorough design validation analysis and on the other hand through extensive pre-assembly and testing. And, once again, full scale integrated pre-assembly and testing of extremely large subsystems is not always possible. Therefore, defining a comprehensive test plan for critical components, critical subsystems and critical subassemblies becomes essential. Logistical challenges are linked to the erection site. Cerro Armazones is a remote site and this needs to be considered when evaluating transport and erection requirements. But it is not only the remoteness of the site that needs to be considered. The size of both Dome and Main Structure require large construction cranes and a well defined erection plan taking into account pre-assembly strategies, limited plan area utilization, erection sequence, erection stability during intermediate stages and, very specifically, efficient coordination between the Dome and the Main Structure erection processes. Managerial issues pose another set of challenges in this project. Both the size of the

  18. Enhancement of Jahani (Firouzabad salt dome lithological units, using principal components analysis

    Directory of Open Access Journals (Sweden)

    Houshang Pourcaseb

    2016-04-01

    Full Text Available In this study, principal components analysis was used to investigate lithological characteristics of Jahani salt dome, Firouzabad. The spectral curves of rocks in the study area show that the evaporate rocks have the highest reflectance at specified wavelengths. The highest reflection has been seen in gypsum and white salt, while minimal reflection can be observed in the igneous rocks from the region. The results show that PCs have significantly low information. It is clear that PC1 shows more information in the highest variance while PC2 has less information. Regional geological map and field controls show compatibility between the enhanced zones and outcrops in the field.

  19. Hydrothermal alteration in the Baca Geothermal System, Redondo Dome, Valles Caldera, New Mexico

    Science.gov (United States)

    Hulen, Jeffrey B.; Nielson, Dennis L.

    1986-02-01

    Thermal fluids circulating in the active hydrothermal system of the resurgent Redondo dome of the Valles caldera have interacted with their diverse host rocks to produce well-zoned alteration assemblages, which not only help locate permeable fluid channels but also provide insight into the system's thermal history. The alteration shows that fluid flow has been confined principally to steeply dipping normal faults and subsidiary fractures as well as thin stratigraphic aquifers. Permeability along many of these channels has been reduced or locally eliminated by hydrothermal self-sealing. Alteration from the surface through the base of the Miocene Paliza Canyon Formation is of three distinctive types: argillic, propylitic, and phyllic. Argillic alteration forms a blanket above the deep water table in formerly permeable nonwelded tuffs. Beneath the argillic zone, pervasive propylitic alteration is weakly developed in felsic host rocks but locally intense in deep intermediate composition volcanics. Strong phyllic alteration is commonly but not invariably associated with major active thermal fluid channels. Phyllic zones yielding no fluid were clearly once permeable but now are hydrothermally sealed. High-temperature alteration phases at Baca are presently found at much lower temperatures. We suggest either that isotherms have collapsed due to gradual cooling of the system, that they have retreated without overall heat loss due to uplift of the Redondo dome, that the system has shifted laterally, or that it has contracted due to a drop in the water table. The deepest Well (B-12, 3423 m) in the dome may have penetrated through the base of the active hydrothermal system. Below a depth of 2440 m in this well, hydrothermal veining largely disappears, and the rocks resemble those developed by isochemical thermal metamorphism. The transition is reflected by temperature logs, which show a conductive thermal gradient below 2440 m. This depth may mark the dome's neutral plane

  20. A reconnaissance geochemical drainage survey of the Harlech Dome, north Wales

    OpenAIRE

    Cooper, D C; Bide, P.J.; Cameron, D. G.; Bell, N.; Allen, P M

    1985-01-01

    A geochemical drainage survey was carried out across 1 050 km’ of the Harlech Dome and adjacent areas at a mean density of 0.85 sample/km2. Fine (-100 mesh) stream sediment, panned concentrate and water samples were collected at every site. Cu, Pb, Zn, MO, As, Ba, Fe, Mn, Co, Ni, Cr, V and Zr were determined in stream sediment samples; Cu, Pb, Zn, Ba, Fe, Mn, Ti, Nl, Ce and Sn in panned concentrates, and Cu, Pb and Zn in water. Gold was determined in panned concentrate...

  1. IRON DOME

    African Journals Online (AJOL)

    ... according to Demeyere, it was not actually possible to view missiles from anything more than the point of view of military doctrine.75 Demeyere goes so far as to say that no treaty addresses missiles nor have states ever attempted to address missiles in a treaty. This however does not place missiles into a black hole.

  2. Psych Dome

    DEFF Research Database (Denmark)

    Computer EEG-controlled audio-visualisation software adapted for use by Sacred Resonance for 'Noosphere: A Vision Quest', a performance at Adelaide Planetarium, as part of the Adelaide Fringe Festival 2016....

  3. Geohydrology of the northern Louisiana salt-dome basin pertinent to the storage of radioactive wastes; a progress report

    Science.gov (United States)

    Hosman, R.L.

    1978-01-01

    Salt domes in northern Louisiana are being considered as possible storage sites for nuclear wastes. The domes are in an area that received regional sedimentation through early Tertiary (Eocene) time with lesser amounts of Quaternary deposits. The Cretaceous-Tertiary accumulation is a few thousand feet thick; the major sands are regional aquifers that extend far beyond the boundaries of the salt-dome basin. Because of multiple aquifers, structural deformation, and variations in the hydraulic characteristics of cap rock, the ground-water hydrology around a salt dome may be highly complex. The Sparta Sand is the most productive and heavily used regional aquifer. It is either penetrated by or overlies most of the domes. A fluid entering the Sparta flow system would move toward one of the pumping centers, all at or near municipalities that pump from the Sparta. Movement could be toward surface drainage where local geologic and hydrologic conditions permit leakage to the surface or to a surficial aquifer. (Woodard-USGS)

  4. The thermal environment of the fiber glass dome for the new solar telescope at Big Bear Solar Observatory

    Science.gov (United States)

    Verdoni, A. P.; Denker, C.; Varsik, J. R.; Shumko, S.; Nenow, J.; Coulter, R.

    2007-09-01

    The New Solar Telescope (NST) is a 1.6-meter off-axis Gregory-type telescope with an equatorial mount and an open optical support structure. To mitigate the temperature fluctuations along the exposed optical path, the effects of local/dome-related seeing have to be minimized. To accomplish this, NST will be housed in a 5/8-sphere fiberglass dome that is outfitted with 14 active vents evenly spaced around its perimeter. The 14 vents house louvers that open and close independently of one another to regulate and direct the passage of air through the dome. In January 2006, 16 thermal probes were installed throughout the dome and the temperature distribution was measured. The measurements confirmed the existence of a strong thermal gradient on the order of 5° Celsius inside the dome. In December 2006, a second set of temperature measurements were made using different louver configurations. In this study, we present the results of these measurements along with their integration into the thermal control system (ThCS) and the overall telescope control system (TCS).

  5. Population specific salinity tolerance in eelgrass (Zostera marina)

    DEFF Research Database (Denmark)

    Salo, Tiina Elina; Pedersen, Morten Foldager; Boström, Christoffer

    2014-01-01

    Salinity is one of the main factors impacting distribution of marine plants and sub-optimal salinities may result in increased resource use and decreased production.We studied the performance and salinity tolerance of eelgrass (Zostera marina L.) originating from two regions with different ambient...... salinities: a low saline (salinity 6) and a high saline (salinity 20) population. Plants fromboth populationswere exposed to a series of fixed salinities (2, 4, 6, 9, 12.5, 15, 20 and 25) for 5 weeks. Both plant origin and salinity affected plant performance significantly. Plant production decreasedwith...... decreasing salinity in both populations,while mortality increased in lowsalinity only in plants originating from the high saline population. The better performance of the low saline population in the lowest salinities indicates a horizontal shift in salinity tolerance among populationswith different origin...

  6. Evaluation and characterization of 30 solar home systems (SHS) Ovonic-Unisolar; Caracterizacion y evaluacion de 30 sistemas FV domiciliarios ovonic-unisolar

    Energy Technology Data Exchange (ETDEWEB)

    Flores, J. Roberto; Agredano, Jaime; Munguia, Gonzalo; Lagunas, Javier; Huacuz, Jorge [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico); Brennan, Steve [Troy, MI (United States)

    2000-07-01

    In this work the first results of the evaluation and characterization of 30 solar home systems (SHS) Ovonic-Unisolar (16 of 30 W and 14 of 60 W of capacity) are presented. The components of the SHS are: One or two PV modules, a charge controller, a nickel metal-hybride (NiMH) battery with a nominal capacity of 85 Ah rated at 3 hours, two or four 8 W lamps, and a CD/CD converter for connecting a radio or a TV W/B a maximum power of 20W. Of all systems evaluated, 29 were installed in three communities of the Oaxaca State, and the other 2 are installed at the Instituto de Investigaciones Electricas (IIE) the laboratory as prototype systems. Before the systems installation at the rural communities, all of them were tested in laboratory. Eight systems installed in the field are being monitoring with data acquisition systems. The main motivation of this projects is to know the behavior of the NiMH battery in the SHS. [Spanish] En este trabajo se presentan los primeros resultados de la caracterizacion y evaluacion de 30 sistemas fotovoltaicos (FV) domiciliarios Ovonic-Unisolar (16 con capacidad de 30 W y 14 con capacidad de 60 W). Los sistemas estan integrados por uno o dos modulos FV de 30 W (dependiendo de la capacidad del sistema), un controlador de carga con termo-interuptor, una bateria del tipo niquel hidruros metalicos (NiHM) con capacidad de 85 Ah a una razon de descarga de 3 horas, 2 o 4 lamparas compactas de alta eficiencia de 8 W y un convertidor CD/CD que permite a los usuarios utilizar una radiograbadora y/o una television B/N con potencia no mayor a 20 W. De estos 30 sistemas FV, 28 se instalaron en 3 comunidades rurales del Estado de Oaxaca y los dos sistemas restantes se tienen instalados en el laboratorio FV del Instituto de Investigaciones Electricas (IIE) como sistemas testigos. Previo a la instalacion en campo, todos los sistemas fueron evaluados en el laboratorio para garantizar su operacion en las comunidades rurales. De los 28 sistemas instalados en

  7. Granitoid magmatism of Alarmaut granite-metamorphic dome, West Chukotka, NE Russia

    Science.gov (United States)

    Luchitskaya, M. V.; Sokolov, S. D.; Bondarenko, G. E.; Katkov, S. M.

    2009-04-01

    Main tectonic elements of West Chukotka are Alazey-Oloy, South-Anyui and Anyui-Chukotka fold systems, formed as a result of collision between structures of North-Asian continent active margin and Chukotka microcontinent [1-3]. South-Anyui fold system, separating Alazey-Oloy and Anyui-Chukotka systems, is considered as suture zon, formed as a result of oceanic basin closing [4-6]. Continent-microcontinent collision resulted in formation of large orogen with of northern and southern vergent structures, complicated by strike-slip deformations [7, 8]. Within Anyui-Chukotka fold system several rises, where most ancient deposits (crystalline basement and Paleozoic cover of Chukotka microcontinent) are exposed, were distinguished [2, 9-11]. Later they were considered as granite-metamorphic domes [12-14]. Alarmaut dome is located at West Chukotka to the north from Bilibino city and is traced from south to north in more than 120 km. General direction of structure is discordant to prevailing NW extensions of tectonic elements of the region. Paleozoic-Triassic deposits are exposed within the Alarmaut dome: 1) D3-C1 - crystalline schists, quartz-feldspar metasandstones, quartzites, marbles (700 m) [11]; 2) C1 - marblized limestones, quartz-feldspar metasandstones, quartzites, amphibole-pyroxene crystalline schists. Limestones contain corals, indicating Visean age of deposits [11]. Metamorphism reaches amphibolite facies, maximum P-T conditions are 660°С and 5 kbar. Migmatites, indicating in situ partial melting, are observed. Intensity of deformations of Paleozoic rocks increases at the boundary with Triassic deposits [11]; in the western part of dome slices of Pz rocks are separated by blastomylonite horizons [14]. Within Alramaut dome granitoids of Lupveem batholith (central part of dome), Bystrinsky pluton (southeastern part), and small Koyvel' and Kelil'vun plutons were studied. New U-Pb SHRIMP zircon data indicate Early Cretaceous (117-112 m.a.) age of granitoids [15

  8. Lava dome emplacement and destruction cyclic process at Popocatépetl volcano, Mexico: The distribution of dome volumes and its consequences on the hazard associated to the current activity

    Science.gov (United States)

    De la Cruz-Reyna, Servando; Gomez-Vazquez, Angel; Mendoza-Rosas, Ana

    2017-04-01

    Popocatépetl is a large stratovolcano surrounded by one of the most densely populated areas of the world. Its eruptive history includes a wide range of eruption types, from moderate effusive episodes to Plinian phases and even massive debris avalanches. The historical record of the last 500 years describes several episodes similar to the current one that began in 1994. The current activity is characterized by the cyclic emplacement and destruction of lava domes, with a count of at least 38 between 1996 and 2015. The previous historical episode (1919-1927) probably emplaced around 10 domes. However, 1200 yBP a major Plinian phase affected human settlements, and at least six other major explosive eruptions have been reported in the Holocene. Such eruptive history leads to question the significance of the ongoing activity in the context of a volcano capable to produce extreme eruptions. The analysis of dome parameters characterizing the current activity offers some insight into the underlying physical process sustaining the eruption, and the conditions that may signal an evolution into higher-intensity phases. Although the process is irregular and non-stationary in the time domain, the maximum volumes and thicknesses of the domes estimated from aerial images are well described by an exponential survival distribution N=No*exp(-V/Va), where No is the number of emplaced domes, Va their average volume, and N the number of domes with volumes equal or exceeding V. A variable buoyancy force caused by the variable density contrast between volatile-rich magma and country rock may offer a possible interpretation of the process. The cyclic character of magma ascent may be a consequence of a self-regulating process caused by intense outgassing of magma controlling buoyancy. The proposed scaling law may then be a consequence of the gravitational energy release of the buoyancy force governing the height and volume of the domes. A significant departure from that scaling law in

  9. Correlation of eruptive products, Volcán Azufral, Colombia: Implications for rapid emplacement of domes and pyroclastic flow units

    Science.gov (United States)

    Williams, Matthew; Bursik, M. I.; Cortes, G. P.; Garcia, A. M.

    2017-07-01

    The eruptive history and morphology of Azufral Volcano, Colombia, is explored and analyzed to provide a more complete picture of past eruptions, as well as to infer what eruption styles may occur in the future. Through the use of principal component analysis on Fe-Ti oxides, domes can be correlated to the pyroclastic deposits, enabling the identification of a full eruptive sequence. The findings suggest that eruptive activity at Azufral Volcano is largely explosive, experiencing long periods of quiescence, punctuated by short periods of pyroclastic activity and volcanic debris avalanches. Geomorphology of the dome complex is reinterpreted to better understand the sequence of dome growth. This reinterpretation, along with geochemical analysis and comparison via PCA, allows for reclassification of a major deposit, originally thought to be a juvenile block-and-ash flow, as a volcanic debris avalanche.

  10. First results from the Beyond EPICA - Oldest Ice pre-site survey in the Dome Fuji region, Antarctica

    Science.gov (United States)

    Binder, Tobias; Karlsson, Nanna; Eisen, Olaf

    2017-04-01

    The Beyond EPICA - Oldest Ice (BE-OI) consortium and its international partners unite a globally unique concentration of scientific expertise and infrastructure for ice-core investigations. It delivers the technical, scientific and financial basis for a comprehensive plan to retrieve an ice core up to 1.5 million years old. The consortium takes care of the pre-site surveys for site selection around Dome C and Dome Fuji, both potentially appropriate regions in East Antarctica. Other science consortia will investigate other regions under the umbrella of the International Partnerships in Ice Core Sciences (IPICS). In this contribution we present first results from the extensive airborne radar survey at the Dome Fuji region, recently obtained in the 2016/17 Antarctic field season. This enables us to confirm and reject earlier estimates on the presence of old ice, potentially more than 1 Ma old, in this region.

  11. The EDC3 chronology for the EPICA Dome C ice core

    Directory of Open Access Journals (Sweden)

    F. Parrenin

    2007-08-01

    Full Text Available The EPICA (European Project for Ice Coring in Antarctica Dome C drilling in East Antarctica has now been completed to a depth of 3260 m, at only a few meters above bedrock. Here we present the new EDC3 chronology, which is based on the use of 1 a snow accumulation and mechanical flow model, and 2 a set of independent age markers along the core. These are obtained by pattern matching of recorded parameters to either absolutely dated paleoclimatic records, or to insolation variations. We show that this new time scale is in excellent agreement with the Dome Fuji and Vostok ice core time scales back to 100 kyr within 1 kyr. Discrepancies larger than 3 kyr arise during MIS 5.4, 5.5 and 6, which points to anomalies in either snow accumulation or mechanical flow during these time periods. We estimate that EDC3 gives accurate event durations within 20% (2σ back to MIS11 and accurate absolute ages with a maximum uncertainty of 6 kyr back to 800 kyr.

  12. Submarine channel evolution linked to rising salt domes, Gulf of Mexico, USA

    Science.gov (United States)

    Carter, Rachel C.; Gani, M. Royhan; Roesler, Toby; Sarwar, Abu K. M.

    2016-08-01

    An examination of halokinetics and channel evolution together in a deepwater system provides an opportunity to investigate how submarine channel morphology is locally affected by rising salt domes. The study area is located in the northern Gulf of Mexico (GOM), directly off the Louisiana continental slope in a prominent salt dome region. The influence of salt growth on submarine channel evolution is relatively understudied, particularly in the GOM. Utilizing high-resolution 3D seismic and well data and seismic geomorphology techniques, a long-lived (~ 3 Myr) Plio-Pleistocene submarine channel system has been investigated to show a relationship between variable phases of salt motion and planform morphology of preserved submarine channels. Our data suggest that local salt motion acts as a driver for submarine channel evolution. During the late Pliocene, when salt moved upward at a relatively fast rate, channels show distinct entrenchment with narrow channel belts and overall less sinuosity. When salt motion slowed down at the beginning of the Pleistocene, channels aggraded rapidly with preserved levees, and moved toward an equilibrium state with the expansion of channel belt widths. As our results indicate, the rate of salt diapirism exerted a first-order control on channel location and morphology and distribution of reservoir-prone units. This study cautions against readily invoking allogenic factors (e.g., sea level and climate) in explaining changes in submarine channel behavior and associated fan sedimentation, particularly in regions with salt tectonics.

  13. Fire reinforces structure of pondcypress (Taxodium distichum var. imbricarium) domes in a wetland landscape

    Science.gov (United States)

    Watts, Adam C.; Kobziar, Leda N.; Snyder, James R.

    2012-01-01

    Fire periodically affects wetland forests, particularly in landscapes with extensive fire-prone uplands. Rare occurrence and difficulty of access have limited efforts to understand impacts of wildfires fires in wetlands. Following a 2009 wildfire, we measured tree mortality and structural changes in wetland forest patches. Centers of these circular landscape features experienced lower fire severity, although no continuous patch-size or edge effect was evident. Initial survival of the dominant tree, pondcypress (Taxodium distichum var. imbricarium), was high (>99%), but within one year of the fire approximately 23% of trees died. Delayed mortality was correlated with fire severity, but unrelated to other hypothesized factors such as patch size or edge distance. Tree diameter and soil elevation were important predictors of mortality, with smaller trees and those in areas with lower elevation more likely to die following severe fire. Depressional cypress forests typically exhibit increasing tree size towards their interiors, and differential mortality patterns were related to edge distance. These patterns result in the exaggeration of a dome-shaped profile. Our observations quantify roles of fire and hydrology in determining cypress mortality in these swamps, and imply the existence of feedbacks that maintain the characteristic shape of cypress domes.

  14. The Geology of East Butte, a Rhyolitic Volcanic Dome on the Eastern Snake River Plain, Idaho

    Science.gov (United States)

    Bretches, J. E.; King, J. S.

    1985-01-01

    East Butte is a prominent volcanic dome located on the eastern Snake River Plain. It is situated 51 km west of Idaho Fallls in the southeast corner of the Idaho National Engineering facility. East Butte rises 350 meters above the Quaternary basalt flows which encircle its 2.4 kilometer diameter base. Its maximum elevation is 2003 meters above sea level. East Butte is composed dominantly of rhyolite. Armstrong and others (1975) determined a K-Ar age of 0.6 +/- m.y. for a rhyolite sample from East Butte. Detailed geologic mapping revealed East Butte to be a single, large cumulo-dome composed dominantly of rhyolite. Major element geochemical analyses indicate that the rhyolite of East Butte is mildly peralkaline (molecular excess of Na2O and K2O over Al2O3 and compositionally homogeneous. Color variations in the East Butte rhyolite result from varying amounts of chemical and physical weathering and to the degree of devitrification that the glass in the groundmass of the rhyolite underwent.

  15. Thermal Loads on a Domed Protuberance Under a Mach 5.7 Boundary Layer

    Science.gov (United States)

    Ostoich, Christopher; Bodony, Daniel; Geubelle, Philippe

    2011-11-01

    A high-fidelity, high-accuracy multi-physics computational tool has been developed to make predictions of structural-thermal response in the hypersonic regime. The predicted surface heat flux distribution was compared with measured data taken from a 1986 experiment in the NASA Langley 8-foot high-temperature tunnel in which a flat plate with a domed protuberance was inserted into a Mach 6.59 flow. The solution from the fluid and thermal domains obtained from the coupled simulation, with experimental comparisons, will be presented. In addition to the typical heating associated with windward-facing surfaces, several other sources of significant differential heating were observed near the dome-plate interface and due to a trailing horseshoe vortex of small size. Data were collected over a long time record (50 seconds) and comments will be given about ignoring transient thermal effects in hypersonic boundary layer calculations. An assessment of gas thermal model assumptions will also be discussed. Supported by the U.S. Air Force Research Laboratory Air Vehicles Directorate under contract number FA8650-06-2-3620.

  16. Emplacement of a silicic lava dome through a crater glacier: Mount St Helens, 2004-06

    Science.gov (United States)

    Walder, J.S.; LaHusen, R.G.; Vallance, J.W.; Schilling, S.P.

    2007-01-01

    The process of lava-dome emplacement through a glacier was observed for the first time after Mount St Helens reawakened in September 2004. The glacier that had grown in the crater since the cataclysmic 1980 eruption was split in two by the new lava dome. The two parts of the glacier were successively squeezed against the crater wall. Photography, photogrammetry and geodetic measurements document glacier deformation of an extreme variety, with strain rates of extraordinary magnitude as compared to normal alpine glaciers. Unlike normal temperate glaciers, the crater glacier shows no evidence of either speed-up at the beginning of the ablation season or diurnal speed fluctuations during the ablation season. Thus there is evidently no slip of the glacier over its bed. The most reasonable explanation for this anomaly is that meltwater penetrating the glacier is captured by a thick layer of coarse rubble at the bed and then enters the volcano's groundwater system rather than flowing through a drainage network along the bed.

  17. The EDC3 chronology for the EPICA Dome C ice core

    Science.gov (United States)

    Parrenin, F.; Barnola, J.-M.; Beer, J.; Blunier, T.; Castellano, E.; Chappellaz, J.; Dreyfus, G.; Fischer, H.; Fujita, S.; Jouzel, J.; Kawamura, K.; Lemieux-Dudon, B.; Loulergue, L.; Masson-Delmotte, V.; Narcisi, B.; Petit, J.-R.; Raisbeck, G.; Raynaud, D.; Ruth, U.; Schwander, J.; Severi, M.; Spahni, R.; Steffensen, J. P.; Svensson, A.; Udisti, R.; Waelbroeck, C.; Wolff, E.

    2007-08-01

    The EPICA (European Project for Ice Coring in Antarctica) Dome C drilling in East Antarctica has now been completed to a depth of 3260 m, at only a few meters above bedrock. Here we present the new EDC3 chronology, which is based on the use of 1) a snow accumulation and mechanical flow model, and 2) a set of independent age markers along the core. These are obtained by pattern matching of recorded parameters to either absolutely dated paleoclimatic records, or to insolation variations. We show that this new time scale is in excellent agreement with the Dome Fuji and Vostok ice core time scales back to 100 kyr within 1 kyr. Discrepancies larger than 3 kyr arise during MIS 5.4, 5.5 and 6, which points to anomalies in either snow accumulation or mechanical flow during these time periods. We estimate that EDC3 gives accurate event durations within 20% (2σ) back to MIS11 and accurate absolute ages with a maximum uncertainty of 6 kyr back to 800 kyr.

  18. Theory and practice of a variable dome splitter for gas chromatography-olfactometry.

    Science.gov (United States)

    Boeker, Peter; Haas, Torsten; Schulze Lammers, Peter

    2013-04-19

    For olfactometric measurements in combination with gas chromatography a device is needed to split the GC effluent between the detector and the sniffing port. Fixed split ratios are obtained by simple flow splitters with appropriate restrictions towards the two outlets. Variable split ratios are possible with additional control flows. One such device is a dome splitter with one input flow (the GC effluent), two output flows (to the two outlets) and two control inputs. Preliminary experiments revealed deviations from the expected split ratios of such a device. The dimensioning of the flow restrictors at only one working point was not sufficient to obtain the expected split ratios over the whole temperature range of a GC run. Therefore a physical model of the flow system has been developed, taking into account the temperature dependence of the restrictors and the internal pressure in the dome. This included the solution of the flow (respectively the mass) balance under the condition of a compressible, isothermal and laminar flow regime. The measurements are in good agreement with theoretical calculations. The model can therefore be used to optimise the dimensions of the restrictions and to calculate the effective split ratio at a given temperature during the GC run. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Development of the Sri Lanka Dome and Links to Air-Sea Interaction

    Science.gov (United States)

    Cullen, K.; Shroyer, E.

    2016-02-01

    The Sri Lanka Dome (SLD) is an upwelling recirculation feature found in the Southwest Monsoon Current that may significantly influence both biological productivity and air-sea interactions in the Bay of Bengal. Here, the twenty-year time series of detrended AVISO satellite absolute dynamic topography is used to track and measure the intensity of the SLD, which shows both a strong seasonal cycle and considerable interannual variability. The dome typically forms in May to the east of Sri Lanka, intensifies through July and August, and migrates to the north and then west before dissipating in September off the coast of northeast Sri Lanka. SLD formation and dissipation, migration path, and magnitude display considerable interannual variability. We also quantify the SLD internal structure using the ARGO float record. The SLD is associated with an elevated pycnocline that is often capped with a fresh surface layer, limiting direct communication of upwelled cold water with the surface. The sea surface temperature response is complex as the subsurface temperature structure is not necessarily monotonic with with height. We also address forcing by remote and local winds and the relation between the SLD and surface heat fluxes through its influence on SST.

  20. Chemical compositions of soluble particles around the Termination 1 in the Dome Fuji ice core

    Science.gov (United States)

    Oyabu, I.; Iizuka, Y.; Sakurai, T.; Suzuki, T.; Miyake, T.; Hirabayashi, M.; Motoyama, H.; Hondoh, T.

    2012-04-01

    Micro sized particles preserved in Antarctic ice cores are useful proxies for reconstructing past climate and environmental changes. The recent studies on chemical compounds of the particles by using the Dome Fuji ice core showed that sulfate salts were main soluble particles, and chemical compositions of primary sulfate salt were calcium sulfate during the glacial maximum and sodium sulfate during the Holocene #1. However, it is still unknown that how chemical compositions of sulfate particles have changed on millennial time scale. In this study, we focused on sulfate salts and sea salts (precursor of sulfate salts) and measured constituent element of non-volatile particles in the Dome Fuji ice core around the Termination 1(9-25 kyr BP). A total of 48 samples were distributed from Dome Fuji ice core section from 298.900m to 582.590m (Holocene to Last Glacial Maximum: LGM, 9-25 kyr BP), with a time resolution of about 320 year. Non-volatile particles were extracted from the samples by sublimation system #2. Constituent elements and diameter of each non-volatile particle were measured by scanning electron micro scope (SEM) and energy dispersive X-ray spectroscopy (EDS). By using a method in our recent paper #3, we made a classification of non-volatile particles into insoluble dust, soluble sulfate salts and soluble chloride salts. Also we assumed that particles containing Ca and S are calcium sulfate, particles containing Na and S are sodium sulfate and particles containing Na and Cl are sodium chloride. We found several fluctuations of calcium sulfate, sodium sulfate, and sodium chloride around the Termination 1, and these fluctuations are associated with changes in terrestrial as well as marine environments. Main sulfate salts changed from calcium sulfate to sodium sulfate after 16.5 kyr BP. A plausible explanation is that sulfuric acid in atmosphere became to react with sodium chloride instead of dusts (calcium carbonate) after 16.5 kyr BP, because atmospheric

  1. Deformation, lava dome evolution, and eruption cyclicity at Merapi volcano, Indonesia

    Science.gov (United States)

    Young, Kirby D.

    Deformation monitoring results are reported here for the period 1988-1998 at Merapi volcano, one of the most active and dangerous volcanoes in Indonesia. Comprehensive databases of various geophysical parameters were concurrently studied and analyzed to 2000, and similar data were subsequently considered during periods of eruption crisis in 2001 and 2006. Of particular emphasis was the study of lava eruption rates based on dome volume estimates and seismic proxies for dome collapse volumes. The detailed study period of deformation includes a major resumption in lava effusion in January 1992 and major dome collapses in November 1994, January 1997, and July 1998. Monitoring techniques employed in the field are of two types. Translational movements were recorded via electronic distance measurements (EDM) on a summit trilateration network, slope distance changes measured to the upper flanks, and other data collected from 1988 to 1995. Tilt changes were detected by a summit and flank network of tilt stations that operated at various times from 1993 to 1998. A major consequence of the deformation results is the documentation of a significant 4-year period of deformation precursory to the 1992 eruption. Cross-crater strain rates accelerated from less than 3 x 10-6/day between 1988 and 1990 to more than 11 x 10-6/day just prior to the January 1992 activity, representing a general, asymmetric extension of the summit during highlevel conduit pressurization. After the vent opened and effusion of lava resumed, strain occurred at a much reduced rate of less than 2 x 10-6/day. The Gendol breach, a pronounced depression formed by the juxtaposition of old lava coulees on the southeast flank, functioned as a major displacement discontinuity. An elevated phase of magma production with respect to the long-term rate for the 20th Century characterized the activity at Merapi volcano, Central Java/Yogyakarta, Indonesia, for the period 1992-2006. Most large (0.2 - 3.4 x 106 m3) dome

  2. Features of West Hackberry SPR Caverns and Internal Structure Of the Salt Dome

    Energy Technology Data Exchange (ETDEWEB)

    Munson, Darrell Eugene [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Underground Storage Technology Dept.

    2006-09-01

    The intent of this report is to examine the internal structure of the West Hackberry salt dome utilizing the information from the geometric configuration of the internal cavern surfaces obtained from graphical representations of sonar survey data. In a general sense, the caverns of West Hackberry are remarkable in the symmetry of their shapes. There are only rather moderate deviations from what would be considered an ideal cylindrical solution mining geometry in these caverns. This finding is in marked contrast to the directional solutioning found in the elliptical cross sectioned, sometimes winged, caverns of Big Hill. None of the persistent lineaments prevalent in Big Hill caverns are evident in West Hackberry caverns. Irregularities of the West Hackberry caverns are restricted to preferential solution formed pits and protuberances with moderate dimensions. In fact, the principal characteristic of West Hackberry caverns is the often large sections of smooth and cylindrical cavern wall. Differences in the cavern characteristics between West Hackberry and Big Hill suggest that the former dome is quite homogeneous, while the latter still retains strong remnants of the interbeds of the original bedded Louann salt. One possible explanation is that the source of the two domes, while both from the Louann mother salt, differs. While the source of the Big Hill dome is directly from the mother salt bed, it appears that the West Hackberry arises from a laterally extruded sill of the mother salt. Consequently, the amount of deformation, and hence, mixing of the salt and interbed material in the extruded sill is significantly greater than would be the case for the directly formed diapir. In West Hackberry, remnants of interbeds apparently no longer exist. An important aspect of the construction of the West Hackberry caverns is the evidence of an attempt to use a uniform solutioning construction practice. This uniformity involved the utilization of single well solutioning and

  3. Stabilising nanofluids in saline environments.

    Science.gov (United States)

    Al-Anssari, Sarmad; Arif, Muhammad; Wang, Shaobin; Barifcani, Ahmed; Iglauer, Stefan

    2017-12-15

    Nanofluids (i.e. nanoparticles dispersed in a fluid) have tremendous potential in a broad range of applications, including pharmacy, medicine, water treatment, soil decontamination, or oil recovery and CO 2 geo-sequestration. In these applications nanofluid stability plays a key role, and typically robust stability is required. However, the fluids in these applications are saline, and no stability data is available for such salt-containing fluids. We thus measured and quantified nanofluid stability for a wide range of nanofluid formulations, as a function of salinity, nanoparticle content and various additives, and we investigated how this stability can be improved. Zeta sizer and dynamic light scattering (DLS) principles were used to investigate zeta potential and particle size distribution of nanoparticle-surfactant formulations. Also scanning electron microscopy was used to examine the physicochemical aspects of the suspension. We found that the salt drastically reduced nanofluid stability (because of the screening effect on the repulsive forces between the nanoparticles), while addition of anionic surfactant improved stability. Cationic surfactants again deteriorated stability. Mechanisms for the different behaviour of the different formulations were identified and are discussed here. We thus conclude that for achieving maximum nanofluid stability, anionic surfactant should be added. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. A global algorithm for estimating Absolute Salinity

    Directory of Open Access Journals (Sweden)

    T. J. McDougall

    2012-12-01

    Full Text Available The International Thermodynamic Equation of Seawater – 2010 has defined the thermodynamic properties of seawater in terms of a new salinity variable, Absolute Salinity, which takes into account the spatial variation of the composition of seawater. Absolute Salinity more accurately reflects the effects of the dissolved material in seawater on the thermodynamic properties (particularly density than does Practical Salinity.

    When a seawater sample has standard composition (i.e. the ratios of the constituents of sea salt are the same as those of surface water of the North Atlantic, Practical Salinity can be used to accurately evaluate the thermodynamic properties of seawater. When seawater is not of standard composition, Practical Salinity alone is not sufficient and the Absolute Salinity Anomaly needs to be estimated; this anomaly is as large as 0.025 g kg−1 in the northernmost North Pacific. Here we provide an algorithm for estimating Absolute Salinity Anomaly for any location (x, y, p in the world ocean.

    To develop this algorithm, we used the Absolute Salinity Anomaly that is found by comparing the density calculated from Practical Salinity to the density measured in the laboratory. These estimates of Absolute Salinity Anomaly however are limited to the number of available observations (namely 811. In order to provide a practical method that can be used at any location in the world ocean, we take advantage of approximate relationships between Absolute Salinity Anomaly and silicate concentrations (which are available globally.

  5. Managing the Economics of Soil Salinity

    OpenAIRE

    Hadrich, Joleen C.

    2011-01-01

    Saline soils result in decreased crop growth and yield with the potential for losing productive farm land. Enterprise budget analysis was extended to include the fixed costs of installing tile drainage to manage soil salinity in the Red River Valley of North Dakota for corn, soybeans, wheat, sugar beets, and barley. Installing tile drainage to manage soil salinity decreased per acre crop profitability from 19-49% due to the large upfront capital investment of tile drainage. These losses can b...

  6. SOIL SALINITY MAPPING USING MULTITEMPORAL LANDSAT DATA

    Directory of Open Access Journals (Sweden)

    A. Azabdaftari

    2016-06-01

    Full Text Available Soil salinity is one of the most important problems affecting many areas of the world. Saline soils present in agricultural areas reduce the annual yields of most crops. This research deals with the soil salinity mapping of Seyhan plate of Adana district in Turkey from the years 2009 to 2010, using remote sensing technology. In the analysis, multitemporal data acquired from LANDSAT 7-ETM+ satellite in four different dates (19 April 2009, 12 October 2009, 21 March 2010, 31 October 2010 are used. As a first step, preprocessing of Landsat images is applied. Several salinity indices such as NDSI (Normalized Difference Salinity Index, BI (Brightness Index and SI (Salinity Index are used besides some vegetation indices such as NDVI (Normalized Difference Vegetation Index, RVI (Ratio Vegetation Index, SAVI (Soil Adjusted Vegetation Index and EVI (Enhamced Vegetation Index for the soil salinity mapping of the study area. The field’s electrical conductivity (EC measurements done in 2009 and 2010, are used as a ground truth data for the correlation analysis with the original band values and different index image bands values. In the correlation analysis, two regression models, the simple linear regression (SLR and multiple linear regression (MLR are considered. According to the highest correlation obtained, the 21st March, 2010 dataset is chosen for production of the soil salinity map in the area. Finally, the efficiency of the remote sensing technology in the soil salinity mapping is outlined.

  7. Salinity Temperature and Roughness Remote Scanner (STARRS)

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides spatially continuous high-resolution surface salinity imagery in a synoptic manner from small aircraft. Its output complements data collected from...

  8. Soil salinity detection from satellite image analysis: an integrated approach of salinity indices and field data.

    Science.gov (United States)

    Morshed, Md Manjur; Islam, Md Tazmul; Jamil, Raihan

    2016-02-01

    This paper attempts to detect soil salinity from satellite image analysis using remote sensing and geographic information system. Salinity intrusion is a common problem for the coastal regions of the world. Traditional salinity detection techniques by field survey and sampling are time-consuming and expensive. Remote sensing and geographic information system offer economic and efficient salinity detection, monitoring, and mapping. To predict soil salinity, an integrated approach of salinity indices and field data was used to develop a multiple regression equation. The correlations between different indices and field data of soil salinity were calculated to find out the highly correlated indices. The best regression model was selected considering the high R (2) value, low P value, and low Akaike's Information Criterion. About 20% variation was observed between the field data and predicted EC from the satellite image analysis. The precision of this salinity detection technique depends on the accuracy and uniform distribution of field data.

  9. Muon radiography and deformation analysis of the lava dome formed by the 1944 eruption of Usu, Hokkaido —Contact between high-energy physics and volcano physics—

    Science.gov (United States)

    TANAKA, Hiroyuki K. M.; YOKOYAMA, Izumi

    2008-01-01

    Lava domes are one of the conspicuous topographic features on volcanoes. The subsurface structure of the lava dome is important to discuss its formation mechanism. In the 1944 eruption of Volcano Usu, Hokkaido, a new lava dome was formed at its eastern foot. After the completion of the lava dome, various geophysical methods were applied to the dome to study its subsurface structure, but resulted in a rather ambiguous conclusion. Recently, from the results of the levelings, which were repeated during the eruption, “pseudo growth curves” of the lava dome were obtained. The curves suggest that the lava dome has a bulbous shape. In the present work, muon radiography, which previously proved effective in imaging the internal structure of Volcano Asama, has been applied to the Usu lava dome. The muon radiography measures the distribution of the “density length” of volcanic bodies when detectors are arranged properly. The result obtained is consistent with the model deduced from the pseudo growth curves. The measurement appears to afford useful method to clarify the subsurface structure of volcanoes and its temporal changes, and in its turn to discuss volcanic processes. This is a point of contact between high-energy physics and volcano physics. PMID:18941290

  10. Muon radiography and deformation analysis of the lava dome formed by the 1944 eruption of Usu, Hokkaido--contact between high-energy physics and volcano physics--.

    Science.gov (United States)

    K M Tanaka, Hiroyuki; Yokoyama, Izumi

    2008-01-01

    Lava domes are one of the conspicuous topographic features on volcanoes. The subsurface structure of the lava dome is important to discuss its formation mechanism. In the 1944 eruption of Volcano Usu, Hokkaido, a new lava dome was formed at its eastern foot. After the completion of the lava dome, various geophysical methods were applied to the dome to study its subsurface structure, but resulted in a rather ambiguous conclusion. Recently, from the results of the levelings, which were repeated during the eruption, "pseudo growth curves" of the lava dome were obtained. The curves suggest that the lava dome has a bulbous shape. In the present work, muon radiography, which previously proved effective in imaging the internal structure of Volcano Asama, has been applied to the Usu lava dome. The muon radiography measures the distribution of the "density length" of volcanic bodies when detectors are arranged properly. The result obtained is consistent with the model deduced from the pseudo growth curves. The measurement appears to afford useful method to clarify the subsurface structure of volcanoes and its temporal changes, and in its turn to discuss volcanic processes. This is a point of contact between high-energy physics and volcano physics.

  11. Hydrogeological characterization of the Nador Plio-Quaternary aquifer, Tipaza (Algeria); Caracterizacion hidrogeologica del acuifero pliocuaternario de Nador, Tipaza (Argelia)

    Energy Technology Data Exchange (ETDEWEB)

    Bouderbala, A.; Remini, B.; Pulido-Bosch, A.

    2014-06-01

    This paper focuses on the hydrogeological and hydrochemical knowledge of the Nador Plio-Quaternary aquifer in Tipaza, situated along the Algerian coastline. It includes the identification of the hydrodynamic aquifer, hydrogeological and piezometric characteristics and, finally, an overview of the hydro-geochemistry of the area. We carried out this study between 2008 and 2013, with piezometric and hydrochemical monitoring of 24 wells in the study area. The physicochemical analysis of water shows that 25 % of the wells in the coastal zone have values of electrical conductivity greater than 3000 μS/cm The Mg{sup 2}+/Ca{sup 2}+ ratio is also higher than one and there are sodium chloride facies due to the mix of freshwater with seawater exceeding 10 % in some places. However, the comparison of the salinity of the groundwater during the period 2008-2013 with 1988-2004 indicates that there is a low dilution due to the reduction of pumping in the aquifer after the construction of the Boukourdane dam. There has also been a more rainy period and a possible return flow from irrigation in the area. (Author)

  12. Tephra studies on the deep Talos Dome ice core, East Antarctic Plateau

    Science.gov (United States)

    Narcisi, B.; Petit, J.; Delmonte, B.; Stenni, B.

    2011-12-01

    In the context of the TALDICE (TALos Dome Ice CorE) project conducted by a consortium of five European nations led by Italy, a 1620-m long ice core has been drilled at Talos Dome (72°49'S, 159°11'E; 2315 m; www.taldice.org), on the eastern edge of the East Antarctic plateau during the field seasons 2004-2008. Owing to its relatively high accumulation rate, this near-coastal core preserves a detailed undisturbed paleoclimate record covering the past 250,000 years, back to Marine Isotope Stage (MIS) 7.5. The Talos Dome ice is a significant volcanic ash archive. During core inspection of the TALDICE core, more than 100 macroscopic tephra layers were located and inventoried, with an average tephra frequency one order of magnitude greater than the tephra frequency in deep cores from inland East Antarctic plateau over the last two glacial cycles. TALDICE prominent tephra layers, studied by scanning electron microscopy, Coulter Counter and electron microprobe analysis, display an alkaline geochemical character indicating an origin in nearby volcanoes of the Melbourne Volcanic Province (McMurdo Volcanic Group). Our tephra record helps reconstruct an improved history of explosive eruptions in northern Victoria Land, supplementing the stratigraphic record obtained by outcrop studies and documenting previously unknown temporal trends and specific episodes. Investigations on less prominent tephra horizons are in progress with the aim of complementing the Holocene volcanic record of local visible beds and establishing the detailed tephrostratigraphy for the region. To date about ten discrete ice sections showing anomalously coarse grain size has proved to contain significant concentrations of unreworked volcanic glass. Single shard major element analyses of some invisible volcanic horizons indicate subalkaline compositions, which are incompatible with Antarctic volcanism and suggesting long-distance tephra transport from either South American and/or New Zealand volcanoes

  13. Aquarius Instrument and Salinity Retrieval

    Science.gov (United States)

    Le Vine, D. M.

    2011-01-01

    Aquarius has been designed to map the surface salinity field of the global ocean from space a parameter important for understanding ocean circulation and its relationship to climate and the global water cycle. Salinity is measured remotely from space by measuring the thermal emission from the ocean surface. This is done at the low frequency end of the microwave spectrum (e.g. 1.4 GHz) where the emission is sufficiently sensitive to changes in salinity to be detected with sophisticated radiometers. The goal is to monitor the seasonal and interannual variation of the large scale features of the surface salinity field in the open ocean by providing maps on a monthly basis with a spatial resolution of 150 km and an accuracy of 0.2 psu. These are challenging requirements that have led to some unique features of the instrument. These include: a) The addition of a co-located scatterometer to help provide a correction for roughness; b) The addition of a polarimetric channel (third Stokes parameter) to the radiometer to help correct for Faraday rotation; c) Asun-synchronous orbit with a 6 pm ascending equatorial crossing to minimize Faraday rotation and with the antennas looking away from the sun toward the nighttime side to minimize contamination by radiation from the sun; and d) An antenna designed to limit side lobes in the direction of rays from the sun. In addition, achieving the accuracy goal of 0.2 psu requires averaging over one month and to do this requires a highly stable radiometer. Aquarius has three separate radiometers that image in pushbroom fashion with the three antenna beams looking across track. The antenna is a 2.5-m diameter, offset parabolic reflector with three feed horns and the three beams are arranged to image with the boresight aligned to look across track, roughly perpendicular to the spacecraft heading and pointing away from the Sun. The three beams point at angles of theta = 25.8 deg., 33.8 deg. and 40.3 deg. with respect to the spacecraft

  14. Na-smectite s in the Cala de Tomate bentonite deposit (Spain): a natural analogue of the salinity effect on the bentonite barrier of a rad waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Perez del Villar, L.; Pelayo, M.; Fernandez, A.M.; Cozar, J.S. [CIEMAT - Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT/DIRE/CEAGP), Madrid (Spain); Delgado, A.; Reyes, E. [Ciencias de la Tierra y Quimica Ambiental Estacion Experimental del Zaidin Dpt., Granada (Spain); Fernandez-Soler, J.M. [Granada Univ., Dpt. de Mineralogia y Petrologia (Spain); Tsige, M. [Facultad de Ciencias Geologicas, Dpt. de Geodinamica, Madrid (Spain)

    2005-07-01

    Within the framework of the ENRESA programme for the assessment of the long-term behaviour of the bentonite-engineered barrier for a deep radwaste geological repository, analogue studies on several bentonite deposits are conducted at CIEMAT. Among these analogue studies, the thermal effect induced by volcanic intrusions on bentonite deposits is highlighted. In the Cabo de Gata volcanic region, there are several analogue scenarios where these studies have been performed, such as the Cala de Tomate bentonite deposit that was intruded by a pyroxene andesite volcanic dome. However, geological, mineralogical, physicochemical, geochemical and stable isotopic data obtained from the smectites do not allow to establish any analogy with the thermal effect expected on the bentonite-engineered barrier of a deep geological repository after burial. Thus, the bentonitisation processes took place after the intrusion of the dome, as a result of meteoric diagenesis intensively developed on faulting zone affecting the parent pyroclastic acid tuffs. This faulting process occurred after the dome intrusion. However, the physicochemical characteristics of these smectites, specially the exchangeable cations, allow to consider this bentonite deposit as a natural analogue of the saline effect on the clayey barrier. This analogy has been established because Na-smectites are present in this deposit and, up to our present knowledge, it is the first time that these smectites occur naturally in the Cabo de Gata-La Serrata de Nijar volcanic region. As a consequence, the main objectives of this work are: i) to characterise these smectites; ii) to establish their genesis and processes affecting them after their formation and iii) to identify the effects on the bentonite-engineered barrier should it were affected by a Na-rich saline waterfront. (authors)

  15. Partial agonist, but not pure antiestrogens stimulate doming, a marker of normal differentiation, in the MCF-7 breast cancer cell line.

    Science.gov (United States)

    Butler, W Barkley; D'Amico, Stephen C; Glassford, William J; Wu, Weizhen

    2012-12-01

    Abstract Background: The mechanisms by which tamoxifen inhibits breast tumor growth are not completely understood. Partial agonist antiestrogens such as tamoxifen may cause the estrogen receptor (ER) to interact with genes different from those activated by ER bound to estradiol. Doming is a property often associated with, and considered a marker of, differentiation in mammary epithelial cells in culture. This study compared the ability of pure and partial agonist antiestrogens to stimulate doming. MCF-7 cells grown in medium with 10% calf serum were treated with antiestrogens. Domes were counted in three rows (width of the 4× field) across the flask. Three partial agonist antiestrogens [4-hydroxytamoxifen (OHT), H1285 and RU 39,411] caused dome formation. None of the pure antiestrogens tested (ICI 164,384, ICI 182,780 and RU 58,668) caused doming. Doming was stimulated in a dose-dependent manner starting at 1 nM OHT with maximum stimulation at 10-100 nM. Estradiol did not stimulate doming, but blocked doming at 1%-10% of the OHT concentration. Trichostatin A (TSA) reduced the level of estrogen receptor alpha (ERα) and adding it 24 h before adding OHT prevented dome formation. OHT and the other partial agonist antiestrogens appear to act through the ER to stimulate doming. The ability of tamoxifen to induce a marker of differentiation may play a role in its inhibition of breast tumors. If so, then the fact that other partial agonist antiestrogens share this ability, but that pure antiestrogens lack it, may be an important consideration in developing new antiestrogens for breast cancer therapy.

  16. Investigation of soil salinity to distinguish boundary line between ...

    African Journals Online (AJOL)

    Gradual drying of Urmia Lake has left vast saline areas all around it, increasing the risk of salinization of agricultural lands next to the Lake. The current research was aimed to predict soil salinity and distinguish the boundary line between saline and agricultural lands by taking in to account the spatial variability of soil salinity ...

  17. Estimation of salinity power potential in India

    Digital Repository Service at National Institute of Oceanography (India)

    Das, V.K.; RamaRaju, D.V.

    Salinity gradient as a source of energy has much potential, but this has been recognized only recently. The energy density of this source is equivalent to about 250 m water head for a salinity difference of 35 ppt. This source exists...

  18. Hydrologic factors controlling groundwater salinity in northwestern ...

    Indian Academy of Sciences (India)

    The types and ages of the main aquifers in this area are the ... Pleistocene age. The aquifers in the area are recharged by seasonal rainfall of the order of 150 mm/year. The relationship of groundwater salinity against the absolute water ... concept, where the water salinity attains its maximum and minimum limits respectively.

  19. Investigations in Marine Chemistry: Salinity II.

    Science.gov (United States)

    Schlenker, Richard M.

    Presented is a science activity in which the student investigates methods of calibration of a simple conductivity meter via a hands-on inquiry technique. Conductivity is mathematically compared to salinity using a point slope formula and graphical techniques. Sample solutions of unknown salinity are provided so that the students can sharpen their…

  20. Salinity extrema in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Shenoi, S.S.C.; Shetye, S.R.; Gouveia, A.D; Michael, G.S.

    salinity of this water due to evaporation in the North Arabian Sea, (2) poleward coastal undercurrent along the west coast of India during the southwest monsoon. The theta-S characteristics of the four salinity extrema are used to put into perspective...

  1. EFFECT OF SALINITY ON SURVIVAL AND LARVAL ...

    African Journals Online (AJOL)

    Laboratory investigations was conducted to gain a better insight into the effect of changing salinity regime on the development and survival of Macrobrachium vollenhoveli larvae. At water temperature of 28 ± 2oC, larvae reared in the salinity range of 0 to 10 ppt showed low survival (<48%), whereas those reared at 12 ...

  2. Structure and origin of Australian ring and dome features with reference to the search for asteroid impact events

    Science.gov (United States)

    Glikson, Andrew

    2018-01-01

    Ring, dome and crater features on the Australian continent and shelf include (A) 38 structures of confirmed or probable asteroid and meteorite impact origin and (B) numerous buried and exposed ring, dome and crater features of undefined origin. A large number of the latter include structural and geophysical elements consistent with impact structures, pending test by field investigations and/or drilling. This paper documents and briefly describes 43 ring and dome features with the aim of appraising their similarities and differences from those of impact structures. Discrimination between impact structures and igneous plugs, volcanic caldera and salt domes require field work and/or drilling. Where crater-like morphological patterns intersect pre-existing linear structural features and contain central morphological highs and unique thrust and fault patterns an impact connection needs to tested in the field. Hints of potential buried impact structures may be furnished by single or multi-ring TMI patterns, circular TMI quiet zones, corresponding gravity patterns, low velocity and non-reflective seismic zones.

  3. Big Cypress fox squirrel (Sciurus niger avicennia) ecology and habitat use in a cypress dome swamp-pine forest mosaic

    Science.gov (United States)

    Kellam, John O.; Jansen, Deborah K.; Johnson, Annette T.; Arwood, Ralph W.; Merrick, Melissa J.; Koprowski, John L.

    2016-01-01

    Forested wetlands are in decline, as are many species that are obligate residents. Big Cypress fox squirrels (BCFS; Sciurus niger avicennia) are a threatened endemic to wet pine and cypress forests in southwestern Florida. The region is characterized by development resulting in habitat loss, habitat fragmentation, and hydrological change that influence the quality of these wet forests. Through radiotelemetry and field observations, we examined the ecology and habitat use of BCFS in a natural cypress dome-pine forest mosaic. BCFS selected cypress domes for food and nests throughout the year. Cypress dome habitats were the only habitat type to be used more than available; however, the availability of nearby pine forest was also important. Home ranges were large relative to other tree squirrels, with male home ranges exceeding female ranges. Males overlapped more females than males, while sharing similar food preferences and use patterns with females, suggesting that the sexual dimorphism in home range size is related to mate searching. Roads and oil extraction pads were used less frequently than expected and were incorporated into home ranges less than randomly generated features. The importance of cypress domes within the wet forests and grasslands of Big Cypress National Preserve demonstrates the value of maintaining this delicate mosaic. PMID:26989265

  4. Simultaneous anterior cruciate ligament reconstruction and dome-shaped high tibial osteotomy for severe medial compartment osteoarthritis of the knee

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kumahashi

    2016-10-01

    Conclusion: An ACL reconstruction combined with a dome-shaped high tibial osteotomy using a locking plate is one option for treating an aged athlete with ACL deficiency and severe medial compartment osteoarthritis, and can allow the athlete to return to sports activity.

  5. Preliminary paragenetic interpretation of the Quaternary topaz rhyolite lava domes of the Blackfoot volcanic field, southeastern Idaho

    Science.gov (United States)

    Lochridge, W. K., Jr.; McCurry, M. O.; Goldsby, R.

    2015-12-01

    The Quaternary topaz rhyolite lava domes of the bimodal, basalt-dominated Blackfoot volcanic field (BVF), SE Idaho occur in three clusters. We refer to these as the China Hat lava dome field (southernmost; ~ 57 ka), and the 1.4 to 1.5 Ma Sheep Island and White Mountain (northernmost) lava dome fields. The rhyolites and surrounding, more voluminous basalt lavas closely resemble coeval Quaternary rocks erupted to the north along the Eastern Snake River Plain segment of the Yellowstone-Snake River Plain volcanic track. However rhyolites in BVF are distinguished by having more evolved Sr- and Nd-isotopic ratios, as well as having phenocryst assemblages that includes hydrous phases (biotite and hornblende), thorite, and vapor-phase topaz. This study seeks to improve our understanding of the unique conditions of magma evolution that led to these differences. We focus on textural features of major and accessory phenocrysts as a basis for inferring paragenesis for rhyolites from the China Hat lava dome field. Preliminary work indicates that there are three sequentially formed populations of textures among magmatic phases: 1. population of anhedral quartz and plagioclase; 2. population of euhedral grains that includes quartz, sandine, plagioclase, biotite, hornblende, Fe-Ti oxides, zircon and apatite; 3. boxy cellular (skeletal?) sanidine and quartz. We speculate that the first population are resorbed antecrysts, the second formed prior to eruption as autocrysts (at or near equilibrium?), and the third formed soon before or during eruption.

  6. Final report on decommissioning of wells, boreholes, and tiltmeter sites, Gulf Coast Interior Salt Domes of Louisiana

    Energy Technology Data Exchange (ETDEWEB)

    1989-07-01

    In the late 1970s, test holes were drilled in northern Louisiana in the vicinity of Vacherie and Rayburn`s Salt Domes as part of the Department of Energy`s (DOE) National Waste Terminal Storage (NWTS) (rename the Civilian Radioactive Waste Management (CRWM)) program. The purpose of the program was to evaluate the suitability of salt domes for long term storage or disposal of high-level nuclear waste. The Institute for Environmental Studies at Louisiana State University (IES/LSU) and Law Engineering Testing Company (LETCo) of Marietta, Georgia performed the initial field studies. In 1982, DOE awarded a contract to the Earth Technology Corporation (TETC) of Long Beach, California to continue the Gulf Coast Salt Dome studies. In 1986, DOE deferred salt domes from further consideration as repository sites. This report describes test well plugging and site abandonment activities performed by SWEC in accordance with Activity Plan (AP) 1--3, Well Plugging and Site Restoration of Work Sites in Louisiana. The objective of the work outlined in this AP was to return test sites to as near original condition as possible by plugging boreholes, removing equipment, regrading, and seeding. Appendices to this report contain forms required by State of Louisiana, used by SWEC to document decommissioning activities, and pertinent documentation related to lease/access agreements.

  7. Metamorphic conditions and structural evolution of the Kesebir-Kardamos dome: Rhodope metamorphic complex (Greece-Bulgaria)

    Science.gov (United States)

    Moulas, Evangelos; Schenker, Filippo Luca; Burg, Jean-Pierre; Kostopoulos, Dimitrios

    2017-03-01

    The synmetamorphic nappe system of the Rhodope Metamorphic Complex has been deformed into dome-and-basin structures attributed to syn- to post-convergent exhumation. We document the deformation style and present new thermobarometric and geochronological constraints for the Kesebir-Kardamos dome in southern Bulgaria and northern Greece. The dome consists of a migmatitic core overlain by high-grade thrust sheets. Kinematic indicators indicate a continuum from ductile to brittle conditions during exhumation. Thermodynamic modeling applied to the high-grade, intermediate thrust sheets yielded peak conditions of 1.2 GPa and ca 730 °C. New U-Pb SHRIMP-II dating of zircons from rocks of the same unit revealed Late Jurassic-Early Cretaceous (145 Ma) as the time of metamorphic crystallization; some zircon rims yielded Eocene ages (53 and 44 Ma) interpreted as having been thermally reset owing to coeval granitoid magmatism. The high-grade rocks were covered by Lutetian-Priabonian marine sediments after exhumation. Slumps suggest that sedimentation took place in a tectonically active environment. Our new structural, petrological and geochronological results suggest that the major shear zone in the core of the Kesebir-Kardamos dome is equivalent to the Late Jurassic-Early Cretaceous Nestos Shear Zone. Post-Jurassic metamorphic ages recorded in the Rhodope most likely represent crustal rather than deep subduction geodynamic processes.

  8. Upward continuation of Dome-C airborne gravity and comparison with GOCE gradients at orbit altitude in east Antarctica

    DEFF Research Database (Denmark)

    Yildiz, Hasan; Forsberg, René; Tscherning, Carl Christian

    2017-01-01

    An airborne gravity campaign was carried out at the Dome-C survey area in East Antarctica between the 17th and 22nd of January 2013, in order to provide data for an experiment to validate GOCE satellite gravity gradients. After typical filtering for airborne gravity data, the cross-over error...

  9. Effect of temperature on the permeability of lava dome rocks from the 2004-2008 eruption of Mount St. Helens

    Science.gov (United States)

    Gaunt, H. Elizabeth; Sammonds, Peter R.; Meredith, Philip G.; Chadderton, Amy

    2016-04-01

    As magma ascends to shallow levels in the volcanic conduit, volatile exsolution can produce a dramatic increase in the crystal content of the magma. During extrusion, low porosity, highly crystalline magmas are subjected to thermal stresses which generate permeable microfracture networks. How these networks evolve and respond to changing temperature has significant implications for gas escape and hence volcano explosivity. Here, we report the first laboratory experimental study on the effect of temperature on the permeability of lava dome rocks under environmental conditions designed to simulate the shallow volcanic conduit and lava dome. Samples were collected for this study from the 2004-2008 lava dome eruption of Mount St. Helens (Washington State, USA). We show that the evolution of microfracture networks, and their permeability, depends strongly on temperature changes. Our results show that permeability decreases by nearly four orders of magnitude as temperature increases from room temperature to 800 °C. Above 800 °C, the rock samples become effectively impermeable. Repeated cycles of heating leads to sample compaction and a reduction in fracture density and therefore a decrease in permeability. We argue that changes in eruption regimes from effusive to explosive activity can be explained by strongly decreasing permeability caused by repeated heating of magma, conduit walls and volcanic plugs or domes. Conversely, magma becomes more permeable as it cools, which will reduce explosivity.

  10. Isotopic and elemental relics of the 1815 AD Tambora eruption in ice from Law Dome, Antarctica

    Science.gov (United States)

    Vallelonga, P.; Candelone, J.-P.; Curran, M. A. J.; Morgan, V. I.; Rosman, K. J. R.

    2003-05-01

    Lead isotopes and Pb, Ba and Bi concentrations have been recently measured at sub-annual resolution in an ice core section from Law Dome, Antarctica, corresponding to the period 1814-1819 AD and containing a SO^{2-}_4signal attributed to the 1815 AD eruption of Tambora volcano in Indonesia. While increasing concentrations of Pb and Bi coincide with the 1817-1818 AD volcanic SO4^{2-} peak, Pb isotope data do not confirm Tambora as the source. Barium concentrations were elevated from 1816.5 to 1818.5 AD, indicating increased atmospheric dust levels. These findings contribute to the growing body of data indicating that effusive, rather than explosive, volcanism is the most important volcanic emission process determining the flux of volcanogenic heavy metals to the polar ice sheets.

  11. Heating/cooling potential and carbon credit earned for dome shaped house

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, M. Jamil; Tiwari, G.N. [Center for Energy Studies, Indian Institute of Technology, Hauz Khas, New Delhi-16 (India); Singh, Anil Kumar; Sharma, Manisha [Energy Research Applications, 211B, Pkt-C, Siddhartha Extension, New Delhi-14 (India); Singh, H.N. [Department of Physics, R.S.S.P.G. College, Pilkhuwa, Ghaziabad, U.P. (India)

    2010-07-01

    In this article, the heating/cooling potential of a dome shaped house has been evaluated on the basis of energy balance under quasi-steady state condition by incorporating the effect of ventilation/earth-air heat exchanger. The study has been carried out for composite climate of New Delhi. Effect of parameters of earth-air heat exchanger (radius of pipe, length of pipe and velocity of air) on heating/cooling potential has also been studied. Analysis of energy saving by using day lighting and CO2 credit earned has also been carried out. It is observed that an over all 732 kWh energy can be saved per year by using day lighting which corresponds to 1.49 tones/year carbon credits earned.

  12. Redatuming of borehole-to-surface electromagnetic data at the Kevin Dome exploration site

    DEFF Research Database (Denmark)

    Cai, Hongzhu; Zhdanov, Michael

    2013-01-01

    The method of redatuming the controlled-source electromagnetic data was introduced in Zhdanov and Cai (2012). The approach is based on a Stratton-Chu type integral and the Lorentz lemma to relate observed EM data on the earth’s surface to EM data on some horizontal plane P located underground....... This upward continuation problem is always well posed. By doing this, we can place more virtual receivers at the earth’s surface and within a much larger area. Compared to traditional interpolation and extrapolation techniques such as polynomial fitting or spline approximation, our method takes into account...... the physics of the EM field, which makes the redatuming more accurate than simple mathematical transformation. In this paper, we illustrate this method by redatuming of borehole-to-surface electromagnetic data at the Kevin Dome exploration site....

  13. The surface layer observed by a high-resolution sodar at DOME C, Antarctica

    Directory of Open Access Journals (Sweden)

    Stefania Argentini

    2014-01-01

    Full Text Available One year field experiment has started on December 2011 at the French - Italian station of Concordia at Dome C, East Antarctic Plateau. The objective of the experiment is the study of the surface layer turbulent processes under stable/very stable stratifications, and the mechanisms leading to the formation of the warming events. A sodar was improved to achieve the vertical/time resolution needed to study these processes. The system, named Surface Layer sodar (SL-sodar, may operate both in high vertical resolution (low range and low vertical resolution (high range modes. In situ turbulence and radiation measurements were also provided in the framework of this experiment. A few preliminary results, concerning the standard summer diurnal cycle, a summer warming event, and unusually high frequency boundary layer atmospheric gravity waves are presented.

  14. Capacitive Tactile Sensor Based on Dielectric Oil Displacement out of a Parylene Dome into Surrounding Channels

    Directory of Open Access Journals (Sweden)

    Seiji Aoyagi

    2012-03-01

    Full Text Available We propose a concept of a flexible sensor array using a novel capacitive force sensor not having a vulnerable electrode on the force applied site. It has a polymer domed structure inside which silicone oil is contained. When the force is applied, the oil is pushed into the surrounding thin channels, where the change in capacitance due to the inflowing dielectric oil is measured between two electrodes on the top and bottom surfaces of the channel. Since the channel does not have a directly applied external force to it, the electrodes do not suffer from damage problems. The change in capacitance was simulated using a simplified flow model. The first trial device of the sensing element has been fabricated. A sensitivity of 0.05 pF/gf was achieved.

  15. Siple Dome ice reveals two modes of millennial CO2 change during the last ice age.

    Science.gov (United States)

    Ahn, Jinho; Brook, Edward J

    2014-04-29

    Reconstruction of atmospheric CO2 during times of past abrupt climate change may help us better understand climate-carbon cycle feedbacks. Previous ice core studies reveal simultaneous increases in atmospheric CO2 and Antarctic temperature during times when Greenland and the northern hemisphere experienced very long, cold stadial conditions during the last ice age. Whether this relationship extends to all of the numerous stadial events in the Greenland ice core record has not been clear. Here we present a high-resolution record of atmospheric CO2 from the Siple Dome ice core, Antarctica for part of the last ice age. We find that CO2 does not significantly change during the short Greenlandic stadial events, implying that the climate system perturbation that produced the short stadials was not strong enough to substantially alter the carbon cycle.

  16. C-105 heel pit removed and C-105 dome cut paves way for new retrieval technology

    Energy Technology Data Exchange (ETDEWEB)

    Mackey, Thomas C.; Sutey, Michael J.

    2013-06-10

    For just the second time, crews have cut a hole in the top of an active radioactive waste storage tank at Hanford. Workers began cutting a 55-inch hole in the top of Tank C-105 last Tuesday night on graveyard shift, completing the cut early Wednesday. The hole will allow for installation of the Mobile Arm Retrieval System (MARS) Vacuum into the tank. The cut was made through 17 inches of concrete and rebar using the newly developed rotary-core cutting system, which uses a laser-guided steel canister with teeth on the bottom to drill a round hole into the tank dome. The project was completed safely and successfully in a high-rad area without contamination or significant dose to workers.

  17. Computer vision: automating DEM generation of active lava flows and domes from photos

    Science.gov (United States)

    James, M. R.; Varley, N. R.; Tuffen, H.

    2012-12-01

    Accurate digital elevation models (DEMs) form fundamental data for assessing many volcanic processes. We present a photo-based approach developed within the computer vision community to produce DEMs from a consumer-grade digital camera and freely available software. Two case studies, based on the Volcán de Colima lava dome and the Puyehue Cordón-Caulle obsidian flow, highlight the advantages of the technique in terms of the minimal expertise required, the speed of data acquisition and the automated processing involved. The reconstruction procedure combines structure-from-motion and multi-view stereo algorithms (SfM-MVS) and can generate dense 3D point clouds (millions of points) from multiple photographs of a scene taken from different positions. Processing is carried out by automated software (e.g. http://blog.neonascent.net/archives/bundler-photogrammetry-package/). SfM-MVS reconstructions are initally un-scaled and un-oriented so additional geo-referencing software has been developed. Although this step requires the presence of some control points, the SfM-MVS approach has significantly easier image acquisition and control requirements than traditional photogrammetry, facilitating its use in a broad range of difficult environments. At Colima, the lava dome surface was reconstructed from recent and archive images taken from light aircraft over flights (2007-2011). Scaling and geo-referencing was carried out using features identified in web-sourced ortho-imagery obtained as a basemap layer in ArcMap - no ground-based measurements were required. Average surface measurement densities are typically 10-40 points per m2. Over mean viewing distances of ~500-2500 m (for different surveys), RMS error on the control features is ~1.5 m. The derived DEMs (with 1-m grid resolution) are sufficient to quantify volumetric change, as well as to highlight the structural evolution of the upper surface of the dome following an explosion in June 2011. At Puyehue Cord

  18. A combined Vibroseis-Explosive survey at Halvfarryggen, a local ice dome in East Antarctica

    Science.gov (United States)

    Hofstede, C. M.; Diez, A.; Eisen, O.; Jansen, D.; Kristoffersen, Y.

    2012-12-01

    We carried out a combined Vibroseis-Explosive survey in combination with a snowstreamer at Halvfarryggen, a local ice dome at a triple point in the vicinity of the German Antarctic research station NeumayerIII. The Vibroseis survey was grid shaped to give spatial information about the glaciological and geological substructure. The center survey line was also surveyed with explosives and compared with the Vibroseis data. Internal ice reflections, clearly visible with explosives are not well visible in the Vibroseis data except for the strongest and deepest internal reflection. We interpret this deepest internal ice reflector as ice crystals orientated in to a single maximum. The ice bed contact we interpret as a frozen till layer overlaying bedrock. From velocity analysis derived from refractions seen in far offset data, we interpret the bedrock as igneous.

  19. Optical sky brightness at Dome A, Antarctica, from the Nigel experiment

    Science.gov (United States)

    Sims, Geoff; Ashley, Michael C. B.; Cui, Xiangqun; Everett, Jon R.; Feng, Longlong; Gong, Xuefei; Hengst, Shane; Hu, Zhongwen; Lawrence, Jon S.; Luong-van, Daniel M.; Shang, Zhaohui; Storey, John W. V.; Wang, Lifan; Yang, Huigen; Yang, Ji; Zhou, Xu; Zhu, Zhengxi

    2010-07-01

    Nigel is a fiber-fed UV/visible grating spectrograph with a thermoelectrically-cooled 256×1024 pixel CCD camera, designed to measure the twilight and night sky brightness from 300nm to 850 nm. Nigel has three pairs of fibers, each with a field-of-view with an angular diameter of 25 degrees, pointing in three fixed positions towards the sky. The bare fibers are exposed to the sky with no additional optics. The instrument was deployed at Dome A, Antarctica in January 2009 as part of the PLATO (PLATeau Observatory) robotic observatory. During the 2009 winter, Nigel made approximately six months of continuous observations of the sky, with typically 104 deadtime between exposures. The resulting spectra provide quantitative information on the sky brightness, the auroral contribution, and the water vapour content of the atmosphere. We present details of the design, construction and calibration of the Nigel spectrometer, as well some sample spectra from a preliminary analysis.

  20. Long-term geochemical surveillance of fumaroles at Showa-Shinzan dome, Usu volcano, Japan

    Science.gov (United States)

    Symonds, R.B.; Mizutani, Y.; Briggs, P.H.

    1996-01-01

    This study investigates 31 years of fumarole gas and condensate (trace elements) data from Showa-Shinzan, a dacitic dome-cryptodome complex that formed during the 1943-1945 eruption of Usu volcano. Forty-two gas samples were collected from the highest-temperature fumarole, named A-1, from 1954 (800??C) to 1985 (336??C), and from lower-temperature vents. Condensates were collected contemporaneously with the gas samples, and we reanalyzed ten of these samples, mostly from the A-1 vent, for 32 cations and three anions. Modeling using the thermochemical equilibrium program, SOLVGAS, shows that the gas samples are mild disequilibrium mixtures because they: (a) contain unequilibrated sedimentary CH4 and NH3; (b) have unequilibrated meteoric water; or (c) lost CO, either by air oxidation or by absorption by the sodium hydroxide sampling solution. SOLVGAS also enabled us to restore the samples by removing these disequilibrium effects, and to estimate their equilibrium oxygen fugacities and amounts of S2 and CH4. The restored compositions contain > 98% H2O with minor to trace amounts of CO2, H2, HCl, SO2, HF, H2S, CO, S2 and CH4. We used the restored gas and condensate data to test the hypotheses that these time-series compositional data from the dome's fumaroles provide: (1) sufficient major-gas data to analyze long-term degassing trends of the dome's magma-hydrothermal system without the influence of sampling or contamination effects; (2) independent oxygen fugacity-versus-temperature estimates of the Showa-Shinzan dacite; (3) the order of release of trace elements, especially metals, from magma; and (4) useful information for assessing volcanic hazards. The 1954-1985 restored A-1 gas compositions confirm the first hypothesis because they are sufficient to reveal three long-term degassing trends: (1) they became increasingly H2O-rich with time due to the progressive influx of meteoric water into the dome; (2) their C/S and S/Cl ratios decreased dramatically while their Cl

  1. The Domes: El Wakil’s Traditionalist Architecture of Quba Mosque

    Science.gov (United States)

    Macca, A. A.; Aryanti, T.

    2017-03-01

    Quba Mosque stands as it is today after being rebuilt and renovated several times, as the sacred and historical place built by Prophet Muhammad PBUH in the first day of his emmigration to Medina. Being the first architecture following his hijra, it reflects the will of the people in their endowment to the mosque. This paper aims at studying the changes throughout the development of the mosque, focusing mainly on the last development designed by the architect El-Wakil, his will to reforge the link between the past and the present and the significance of understanding the Islamic culture, philosophy, and architecture. This study employed a literature review to capture the mosque’s architectural features developed by El-Wakil. It argues that the elements of the mosque, particularly the domes, are products of El-Wakil’s vision and defence for traditionalism. His use of traditionalist approach shows his notion of what Islamic architecture is.

  2. Measuring Snow Grain Size with the Near-Infrared Emitting Reflectance Dome (NERD)

    Science.gov (United States)

    Schneider, A. M.; Flanner, M.

    2014-12-01

    Because of its high visible albedo, snow plays a large role in Earth's surface energy balance. This role is a subject of intense study, but due to the wide range of snow albedo, variations in the characteristics of snow grains can introduce radiative feedbacks in a snow pack. Snow grain size, for example, is one property which directly affects a snow pack's absorption spectrum. Previous studies model and observe this spectrum, but potential feedbacks induced by these variations are largely unknown. Here, we implement a simple and inexpensive technique to measure snow grain size in an instrument we call the Near-infrared Emitting Reflectance Dome (NERD). A small black styrene dome (~17cm diameter), fitted with two narrowband light-emitting diodes (LEDs) centered around 1300nm and 1550nm and three near-infrared reverse-biased photodiodes, is placed over the snow surface enabling a multi-spectral measurement of the hemispheric directional reflectance factor (HDRF). We illuminate the snow at each wavelength, measure directional reflectance, and infer grain size from the difference in HDRFs measured on the same snow crystals at fixed viewing angles. We validate measurements from the NERD using two different reflectance standards, materials designed to be near perfect Lambertian reflectors, having known, constant reflectances (~99% and ~55%) across a wide range of wavelengths. Using a 3D Monte Carlo model simulating photon pathways through a pack of spherical snow grains, we calculate the difference in HDRFs at 1300nm and 1550nm to predict the calibration curve for a wide range of grain sizes. This theoretically derived curve gives a relationship between effective radius and the difference in HDRFs and allows us to approximate grain sizes using the NERD in just a few seconds. Further calibration requires knowledge of truth values attainable using a previously validated instrument or measurements from an inter-comparison workshop.

  3. Rift-related volcanism and karst geohydrology of the southern Ozark Dome

    Science.gov (United States)

    Harrison, Richard W.; Weary, David J.; Orndorff, Randall C.; Repetski, John E.; Pierce, Herbert A.; Lowell, Gary R.; Evans, Kevin R.; Aber, James S.

    2010-01-01

    This field trip examines the geology and geohydrology of a dissected part of the Salem Plateau in the Ozark Plateaus province of south-central Missouri. Rocks exposed in this area include karstified, flat-lying, lower Paleozoic carbonate platform rocks deposited on Mesoproterozoic basement. The latter is exposed as an uplift located about 40 mi southwest of the St. Francois Mountains and form the core of the Ozark dome. On day 1, participants will examine and explore major karst features developed in Paleozoic carbonate strata on the Current River; this will include Devil's Well and Round Spring Cavern as well as Montauk, Round, Alley, and Big Springs. The average discharge of the latter is 276 × 106 gpd and is rated in the top 20 springs in the world. Another, Alley Spring, is equally spectacular with an average discharge of 81 × 106 gpd. Both are major contributors to the Current and Eleven Point River drainage system which includes about 50 Mesoproterozoic volcanic knobs and two granite outcrops. These knobs are mainly caldera-erupted ignimbrites with a total thickness of 7–8 km. They are overlain by post-collapse lavas and intruded by domes dated at 1470 Ma. Volcaniclastic sediment and air-fall lapilli tuff are widely distributed along this synvolcanic unconformity. On day 2, the group will examine the most important volcanic features and the southernmost granite exposure in Missouri. The trip concludes with a discussion of the Missouri Gravity Low, the Eminence caldera, and the volcanic history of southern Missouri as well as a discussion of geologic controls on regional groundwater flow through this part of the Ozark aquifer.

  4. Performance of a Small-Scale, Variable Temperature Fixed Dome Digester in a Temperate Climate

    Directory of Open Access Journals (Sweden)

    Juan M. Castano

    2014-09-01

    Full Text Available Small-scale digesters, similar to popular Chinese designs, have the potential to address the energy needs of smaller dairy farmers in temperate U.S. climates. To assess this potential, a 1.14 m3 (300 gallon modified fixed-dome digester was installed and operated, at variable temperatures (5.3 to 27.9 °C typical of the Midwestern United States, from March 2010 to March 2011 (363 days. Temperature, gas production, and other variables were recorded. The system was fed with dilute dairy manure with 6% volatile solids (VS and an organic loading rate (OLR ranging from 0.83 to 2.43 kg volatile solids (VS/m3/day. The system was loaded with no interruption and exhibited no signs of inhibition from July 2010 to mid-November 2010 (129 days. During this period the digester temperature was over 20 °C with an average daily biogas production of 842 ± 69 L/day, a methane yield of 0.168 m3/kg VS added, and a Volatile Solids reduction of 36%. After the temperature dropped below 20 °C, the digester showed signs of inhibition and soured. These findings suggest that an ambient temperature, modified fixed dome digester could operate without temperature inhibition for approximately six months (169 days a year in a temperate climate when digester temperatures exceed 20 °C. However, during colder months the digester temperature must maintained above 20 °C for viable gas production year round.

  5. Momentum- and Heat-Flux Parametrization at Dome C, Antarctica: A Sensitivity Study

    Science.gov (United States)

    Vignon, Etienne; Genthon, Christophe; Barral, Hélène; Amory, Charles; Picard, Ghislain; Gallée, Hubert; Casasanta, Giampietro; Argentini, Stefania

    2017-02-01

    An extensive meteorological observational dataset at Dome C, East Antarctic Plateau, enabled estimation of the sensitivity of surface momentum and sensible heat fluxes to aerodynamic roughness length and atmospheric stability in this region. Our study reveals that (1) because of the preferential orientation of snow micro-reliefs (sastrugi), the aerodynamic roughness length z0 varies by more than two orders of magnitude depending on the wind direction; consequently, estimating the turbulent fluxes with a realistic but constant z0 of 1 mm leads to a mean friction velocity bias of 24 % in near-neutral conditions; (2) the dependence of the ratio of the roughness length for heat z_{0t} to z0 on the roughness Reynolds number is shown to be in reasonable agreement with previous models; (3) the wide range of atmospheric stability at Dome C makes the flux very sensitive to the choice of the stability functions; stability function models presumed to be suitable for stable conditions were evaluated and shown to generally underestimate the dimensionless vertical temperature gradient; as these models differ increasingly with increases in the stability parameter z / L, heat flux and friction velocity relative differences reached 100 % when z/L > 1; (4) the shallowness of the stable boundary layer is responsible for significant sensitivity to the height of the observed temperature and wind data used to estimate the fluxes. Consistent flux results were obtained with atmospheric measurements at heights up to 2 m. Our sensitivity study revealed the need to include a dynamical parametrization of roughness length over Antarctica in climate models and to develop new parametrizations of the surface fluxes in very stable conditions, accounting, for instance, for the divergence in both radiative and turbulent fluxes in the first few metres of the boundary layer.

  6. On the dynamics of the Sri Lanka Dome in the Bay of Bengal

    Science.gov (United States)

    Burns, Jessica M.; Subrahmanyam, Bulusu; Murty, V. S. N.

    2017-09-01

    East of Sri Lanka, in the northern Indian Ocean, a cold dome, known as the Sri Lanka Dome (SLD), develops during southwest monsoon season (June-September). The SLD first forms around May, matures in July, and decays around September, in association with the strong cyclonic wind stress curl. In this study, the structure and dynamics of SLD in response to the climatic events such as the Indian Ocean Dipole (IOD) are examined. Our results reveal that these climatic events modulated the subsurface temperature variability in the thermocline at ˜100 m depth, whose signature was also evident in the satellite-derived sea surface height (SSH) anomaly in the SLD region. We find that the mechanisms for the formation of SLD are consistent with previous research, and there is year-to-year variability in the SLD dynamics. This study also reveals that the atmospheric parameters including vertical wind shear and midtropospheric relative humidity are high over the SLD region and adjacent southern Bay of Bengal and show an upward (increasing) trend over the decades. This has impacted the atmospheric parameters over the northern Bay of Bengal over the decades and as a consequence the total number of monsoon depressions (June-September) decreased over the decades from 1980 to 2015, as reported by the India Meteorological Department, New Delhi. Thus, the new insight emerged from this study is the variability in the cyclogenesis and the occurrence of total number of monsoon depressions over northern Bay of Bengal over the decades is much related to the SLD dynamics.

  7. Response of Stream Biodiversity to Increasing Salinization

    Science.gov (United States)

    Hawkins, C. P.; Vander Laan, J. J.; Olson, J. R.

    2014-12-01

    We used a large data set of macroinvertebrate samples collected from streams in both reference-quality (n = 68) and degraded (n = 401) watersheds in the state of Nevada, USA to assess relationships between stream biodiversity and salinity. We used specific electrical conductance (EC)(μS/cm) as a measure of salinity, and applied a previously developed EC model to estimate natural, baseflow salinity at each stream. We used the difference between observed and predicted salinity (EC-Diff) as a measure of salinization associated with watershed degradation. Observed levels of EC varied between 22 and 994 μS/cm across reference sites and 22 to 3,256 uS/cm across non-reference sites. EC-Diff was as high as 2,743 μS/cm. We used a measure of local biodiversity completeness (ratio of observed to expected number of taxa) to assess ecological response to salinity. This O/E index decreased nearly linearly up to about 25% biodiversity loss, which occurred at EC-Diff of about 300 μS/cm. Too few sites had EC-Diff greater than 300 μS/cm to draw reliable inferences regarding biodiversity response to greater levels of salinization. EC-Diff increased with % agricultural land use, mine density, and % urban land use in the watersheds implying that human activities have been largely responsible for increased salinization in Nevada streams and rivers. Comparison of biological responses to EC and other stressors indicates that increased salinization may be the primary stressor causing biodiversity loss in these streams and that more stringent salinity water quality standards may be needed to protect aquatic life.

  8. Reconstructing Past Ocean Salinity ((delta)18Owater)

    Energy Technology Data Exchange (ETDEWEB)

    Guilderson, T P; Pak, D K

    2005-11-23

    Temperature and salinity are two of the key properties of ocean water masses. The distribution of these two independent but related characteristics reflects the interplay of incoming solar radiation (insolation) and the uneven distribution of heat loss and gain by the ocean, with that of precipitation, evaporation, and the freezing and melting of ice. Temperature and salinity to a large extent, determine the density of a parcel of water. Small differences in temperature and salinity can increase or decrease the density of a water parcel, which can lead to convection. Once removed from the surface of the ocean where 'local' changes in temperature and salinity can occur, the water parcel retains its distinct relationship between (potential) temperature and salinity. We can take advantage of this 'conservative' behavior where changes only occur as a result of mixing processes, to track the movement of water in the deep ocean (Figure 1). The distribution of density in the ocean is directly related to horizontal pressure gradients and thus (geostrophic) ocean currents. During the Quaternary when we have had systematic growth and decay of large land based ice sheets, salinity has had to change. A quick scaling argument following that of Broecker and Peng [1982] is: the modern ocean has a mean salinity of 34.7 psu and is on average 3500m deep. During glacial maxima sea level was on the order of {approx}120m lower than present. Simply scaling the loss of freshwater (3-4%) requires an average increase in salinity a similar percentage or to {approx}35.9psu. Because much of the deep ocean is of similar temperature, small changes in salinity have a large impact on density, yielding a potentially different distribution of water masses and control of the density driven (thermohaline) ocean circulation. It is partly for this reason that reconstructions of past salinity are of interest to paleoceanographers.

  9. Outline of surface mass balance at Dome Fuji, East Antarctica, by the stake method from 1995 to 2006

    Directory of Open Access Journals (Sweden)

    Takao Kameda

    2008-06-01

    Full Text Available This paper describes observational results of surface mass balance (SMB at Dome Fuji (77°19'01″S, 39°42'11″E; 3810m a.s.l., East Antarctica from 1995 to 2006. The SMB was estimated using 36 bamboo stakes (grid of 6×6, placed at 20m intervals. The heights of the stake tops from the snow surface were measured at 0.5cm resolution twice monthly in 1995, 1996, 1997, and 2003, and once a year for the rest of the study period. The annual SMB from 1995 to 2006 at Dome Fuji was 27.3±1.5kgm^a^. This result agrees well with the annual SMB from AD 1260 to 1993 (26.4kgm^a^, estimated from volcanic signals in the Dome Fuji ice core. From 1995 to 2006, there were 37 incidences of negative or zero annual SMB, which was 8.6%. Compared with similar studies at Vostok, South Pole and Dome C, we found that a site with SMB over 190kgm^a^ is expected to have annual snow accumulation at the 95% confidence level. Sites from 1500 to 2500m above sea level fit the criteria on the Antarctic ice sheet. According to stake and snow pit observations at Vostok, we estimated that the probability of an annual layer missing (hiatus at Dome Fuji under present-day and glacial conditions are 9.4% and 11.4%, respectively. Variations of SMB measured by 36-stakes for 12 years were also analyzed.

  10. Geologic technical assessment of the Richton salt dome, Mississippi, for potential expansion of the U.S. strategic petroleum reserve.

    Energy Technology Data Exchange (ETDEWEB)

    Snider, Anna C.; Rautman, Christopher Arthur; Looff, Karl M. (Geologic Consultant)

    2006-01-01

    Technical assessment and remodeling of existing data indicates that the Richton salt dome, located in southeastern Mississippi, appears to be a suitable site for expansion of the U.S. Strategic Petroleum Reserve. The maximum area of salt is approximately 7 square miles, at a subsurface elevation of about -2000 ft, near the top of the salt stock. Approximately 5.8 square miles of this appears suitable for cavern development, because of restrictions imposed by modeled shallow salt overhang along several sides of the dome. The detailed geometry of the overhang currently is only poorly understood. However, the large areal extent of the Richton salt mass suggests that significant design flexibility exists for a 160-million-barrel storage facility consisting of 16 ten-million-barrel caverns. The dome itself is prominently elongated from northwest to southeast. The salt stock appears to consist of two major spine features, separated by a likely boundary shear zone trending from southwest to northeast. The dome decreases in areal extent with depth, because of salt flanks that appear to dip inward at 70-80 degrees. Caprock is present at depths as shallow as 274 ft, and the shallowest salt is documented at -425 ft. A large number of existing two-dimensional seismic profiles have been acquired crossing, and in the vicinity of, the Richton salt dome. At least selected seismic profiles should be acquired, examined, potentially reprocessed, and interpreted in an effort to understand the limitations imposed by the apparent salt overhang, should the Richton site be selected for actual expansion of the Reserve.

  11. Application of Landsat multispectral scanner data and sediment spectral reflectance measurements to mapping of the Meatiq Dome, Egypt

    Science.gov (United States)

    Jacobberger, P. A.; Arvidson, R. E.; Rashka, D. L.

    1983-10-01

    Lithologic boundaries, structural elements and provenance of wadi sediments were determined for the Meatiq Dome in the central Eastern Desert of Egypt, using digitally processed Landsat multispectral scanner data in combination with laboratory spectral reflectance measurements. Optimally enhanced, principal-component color composite images were used to interpolate between field traverses in rugged terrain, to delineate contacts, and to clarify structural relationships in conjunction with extensive field work by Sturchio et al. Atmospherically corrected Landsat spectra were compared with petrographic data and laboratory spectral reflectance measurements, using a technique developed by Evans and Adams, to define the provenance of sediments in a wadi within the Meatiq Dome area. Contacts between the dome's granite and granite gneiss core, peripheral mafic mylonites, and the ophiolitic sequence outside the dome were distinguished. Small tonalite bodies were at the limits of discriminability but were mappable when the images were used in conjunction with field data. A large wadi within the dome exhibits interior drainage and carries only granitic-derived sediments, as distinct from a separate wadi system carrying a mix of materials. Coarseness of spectral measurements along with bias introduced by standard sample-preparation methods are the primary sources of error in the spectral comparisons, but the results obtained are consistent with the known geologic environment. The use of these techniques with corrected and optimally enhanced digital Landsat data proved to be a valuable added tool to field mapping efforts. *Present address: Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, Washington, D.C. 20560

  12. Surface drifters measuring sea water salinity

    Science.gov (United States)

    Reverdin, Gilles; Centurioni, Luca; Sena-Martins, Meike; Garcia-Ladona, Emilio; Ballabrera, Joaquim; Salvador, Joaquin; Sommer, Anna; Boutin, Jacqueline

    2017-04-01

    Surface drifters have been introduced in the early 1990s by P.P. Niiler to measure the salinity of the near-surface water as well as its temperature. First, they were deployed to document large scale advection of surface salinity fronts, such as during TOGA-COARE (1991). More recently, salinity drifter data were used for three purposes: 1 - provide in situ data coverage for validation of sea surface (SSS) products, such as provided by band-L microwave radiometry from satellite missions, Aquarius, SMOS, SMAP 2 - provide data for better understanding upper ocean response to air-sea interactions, such as during rainfall, or near-surface warming during low wind events 3 - provide estimates of surface advection of salinity features and their contribution to ocean freshwater budget We will review the drifters that have been deployed and where data were collected, the challenges encountered in correcting the data, ongoing plans and future developments. A comparison of salinity data of more than 60 SVP drifters to SMOS and Aquarius SSS fields in the North Atlantic subtropical gyre illustrates the potential for validating products from satellite missions over more than a year (SPURS-1 2012-2013 experiment). Data collocated during tropical rain events illustrate a short-term response of near-surface salinity and temperature that can be quantified, although we lack precise collocated wind data. It is rather consistent with independently-derived surface salinity response to rain based on SMOS salinity retrievals, and model estimations. An extreme case of close to 10 psu near-surface salinity drop due to rainfall is presented. Recent salinity drifter deployments in the rainy region of the eastern Pacific ITCZ (SPURS-2 2016 experiment) illustrate the small time and space scale variability associated with freshwater lenses in this region. Some data from a new tag (surpact) will be presented with simultaneous estimates of sea state, rain rate, temperature and salinity during rain

  13. Influence of salinity and cadmium on the survival and ...

    African Journals Online (AJOL)

    osmoregulated at salinities between 5 and 25 and osmoconformed at salinities greater than 25. Chiromantes eulimene followed a hyper-hypo-osmoregulatory strategy; it hyper-regulated in salinities from 0 up to isosmotic conditions at about 28 (c.

  14. Salinity and survival of Martesia striata (Linn) in Cochin harbour

    OpenAIRE

    Cheriyan, P.V.; Cherian, C.J.

    1980-01-01

    The effects of salinity variations on the survival of Martesia striata from Cochin harbour are presented. It is observed that at least a few of the animals survive the low saline conditions during monsoon. Laboratory experiments showed the lethal salinity as 6‰ when animals acclimatised in 34‰ were subjected to abrupt changes in salinity. But acclimatisation to 17‰ salinity showed a downward shift in the lethal salinity to 4‰. The present observations indicate that M. striata is euryhaline ar...

  15. Estuarine Salinity Mapping From Airborne Radiometry

    Science.gov (United States)

    Walker, J. P.; Gao, Y.; Cook, P. L. M.; Ye, N.

    2016-12-01

    Estuaries are critical ecosystems providing both ecological habitat and human amenity including boating and recreational fishing. Salinity gradients, caused by the mixing of fresh and salt water, exert an overwhelming control on estuarine ecology and biogeochemistry as well as being a key tracer for model calibration. At present, salinity monitoring within estuaries typically uses point measurements or underway boat-based methods, which makes sensing of localised phenomena such as upwelling of saline bottom water difficult. This study has pioneered the use of airborne radiometry (passive microwave) sensing as a new method to remotely quantify estuarine salinity, allowing rapid production of high resolution surface salinity maps. The airborne radiometry mapping was conducted for the Gippsland Lakes, the largest estuary in Australia, in February, July, October and November of 2015, using the Polarimetric L-band Microwave Radiometer (PLMR). Salinity was retrieved from the brightness temperature collected by PLMR with results validated against boat sampling conducted concurrently with each flight. Results showed that the retrieval accuracy of the radiative transfer model was better than 5 ppt for most flights. The spatial, temporal and seasonal variations of salinity observed in this study are also analysed and discussed.

  16. Sea-surface salinity: the missing measurement

    Science.gov (United States)

    Stocker, Erich F.; Koblinsky, Chester

    2003-04-01

    Even the youngest child knows that the sea is salty. Yet, routine, global information about the degree of saltiness and the distribution of the salinity is not available. Indeed, the sea surface salinity measurement is a key missing measurement in global change research. Salinity influences circulation and links the ocean to global change and the water-cycle. Space-based remote sensing of important global change ocean parameters such as sea-surface temperature and water-cycle parameters such as precipitation have been available to the research community but a space-based global sensing of salinity has been missing. In July 2002, the National Aeronautical and Space Administration (NASA) announced that the Aquarius mission, focused on the global measurement of sea surface salinity, is one of the missions approved under its ESSP-3 program. Aquarius will begin a risk-reduction phase during 2003. Aquarius will carry a multi-beam 1.4 GHz (L-band) radiometer used for retrieving salinity. It also will carry a 1.2 GHz (L-band) scatterometer used for measuring surface roughness. Aquarius is tentatively scheduled for a 2006 launch into an 8-day Sun-synchronous orbit. Aquarius key science data product will be a monthly, global surface salinity map at 100 km resolution with an accuracy of 0.2 practical salinity units. Aquarius will have a 3 year operational period. Among other things, global salinity data will permit estimates of sea surface density, or buoyancy, that drives the ocean's three-dimensional circulation.

  17. Two- and three-dimensional topographic analysis of pathologically myopic eyes with dome-shaped macula and inferior staphyloma by spectral domain optical coherence tomography.

    Science.gov (United States)

    García-Ben, Antonio; Kamal-Salah, Radua; García-Basterra, Ignacio; Gonzalez Gómez, Ana; Morillo Sanchez, María José; García-Campos, Jose Manuel

    2017-05-01

    To investigate the posterior anatomical structure of pathologically myopic eyes with dome-shaped macula and inferior staphyloma using spectral domain optical coherence tomography (SD-OCT). Our database of 260 pathologically myopic eyes was analyzed retrospectively to identify patients with dome-shaped macula and inferior staphyloma. All patients underwent vertical and horizontal SD-OCT scans across the central fovea, with three-dimensional macular map reconstruction. Best-corrected visual acuity, axial length, and choroidal thickness measurements were recorded. The macular bulge height was also analyzed in eyes with dome-shaped macula. In the three-dimensional images, the symmetry and orientation of the main plane of the inward incurvation of the macula were examined. Twenty-eight (10.7%) of the 260 pathologically myopic eyes had dome-shaped macula of one of three different types: a round radially symmetrical dome (eight eyes, 28.5%), a horizontal axially symmetrical oval-shaped dome (15 eyes, 53.5%), or a vertical axially symmetrical oval-shaped dome (five eyes, 17.8%). The macular bulge height was significantly greater in horizontal oval-shaped dome eyes (p = 0.01, for each comparison). Inferior posterior staphylomas were observed in ten (3.8%) of the 260 pathologically myopic eyes with asymmetrical macular bends. Vertical and horizontal OCT sectional scanning in combination with three-dimensional macular map reconstruction provides important information for understanding the posterior anatomical structure of dome-shaped macula and inferior staphyloma in pathologically myopic eyes.

  18. Wildland Fire Induced Heating of Dome 375 Perma-Con®

    Energy Technology Data Exchange (ETDEWEB)

    Flores, Eugene Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-09

    AET-1 was tasked by ADEM with determining the temperature rise in the drum contents of drums stored in the Dome 375 Perma-Con® at TA-54 given a wildland fire. The wildland fire causes radiative and convective heating on the Perma-Con® exterior. The wildland fire time histories for the radiative and convective heating environment were provided to AET-1 by EES-16. If the calculated temperature rise results in a drum content temperature over 40 °C, then ADEM desires a design solution to ensure the peak temperature remains below 40 °C. An axi-symmetric FE simulation was completed to determine the peak temperature of the contents of a drum stored in the Dome 375 Perma-Con® during a wildland fire event. Three wildland fire time histories for the radiative and convective heat transfer were provided by EES-16 and were inputs for the FE simulation. The maximum drum content temperature reached was found to be 110 °C while using inputs from the SiteG_2ms_4ign_wind_from_west.xlsx time history input and not including the SWB in the model. Including the SWB in the results in a peak drum content temperature of 61 °C for the SiteG_2ms_4ign_wind_from_west.xlsx inputs. EES-16 decided that by using fuel mitigation efforts, such as mowing the grass and shrubs near the Perma-Con® they could reduce the shrub/grass fuel loading near the Perma-Con® from 1.46 kg/m2 to 0.146 kg/m2 and by using a less conservative fuel loading for the debris field inside the Dome 375 perimeter, reducing it from 0.58 kg/m2 to 0.058 kg/m2 in their model. They also greatly increased the resolution of their radiation model and increased the accuracy of their model’s required convergence value. Using this refined input the maximum drum content temperature was found to be 28 °C with no SWB present in the model. Additionally, this refined input model was modified to include worst case emissivity values for the concrete, drum and Perma-Con® interior, along with adding a

  19. Biochar Mitigates Salinity Stress in Potato

    DEFF Research Database (Denmark)

    Akhtar, S S; Andersen, Mathias Neumann; Liu, Fulai

    2015-01-01

    A pot experiment was conducted in a climate-controlled greenhouse to investigate the growth, physiology and yield of potato in response to salinity stress under biochar amendment. It was hypothesized that addition of biochar may improve plant growth and yield by mitigating the negative effect...... capability of biochar. Results indicated that biochar was capable to ameliorate salinity stress by adsorbing Na+. Increasing salinity level resulted in significant reductions of shoot biomass, root length and volume, tuber yield, photosynthetic rate (An), stomatal conductance (gs), midday leaf water...... with the respective non-biochar control. Decreased Na+, Na+/K+ ratio and increased K+ content in xylem with biochar amendment also indicated its ameliorative effects on potato plants in response to salinity stress. The results suggested that incorporation of biochar might be a promising approach for enhancing crop...

  20. Saline water irrigation of quinoa and chickpea

    DEFF Research Database (Denmark)

    Hirich, A.; Jelloul, A.; Choukr-Allah, R.

    2014-01-01

    A pot experiment was conducted in the south of Morocco to evaluate the response of chickpea and quinoa to different irrigation water salinity treatments (1, 4, 7 and 10 dS m-1 for chickpea and 1, 10, 20 and 30 dS m-1 for quinoa). Increasing salinity affected significantly (P ... and height and caused delay and reduction in seed emergence, quinoa was shown to be more resistant than chickpea. Dry biomass, seed yield, harvest index and crop water productivity were affected significantly (P ... and seed yield for both quinoa and chickpea while increasing salinity resulted in increase - in the case of quinoa - and decrease - in the case of chickpea - in harvest index and crop water productivity. Na+ and Na+/K+ ratio increased with increasing irrigation water salinity, while K+ content decreased...

  1. Hypertonic saline for bronchiolitis in infants

    National Research Council Canada - National Science Library

    Grewal, Simran; Goldman, Ran D

    2015-01-01

    Recently, a 1-year-old patient returned from admission in the hospital for bronchiolitis, and the report I received indicated that he was treated with inhaled hypertonic saline, among other treatments...

  2. Geomechanical testing of MRIG-9 core for the potential SPR siting at the Richton salt dome.

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, Dennis P.; Broome, Scott Thomas; Bronowski, David R.; Bauer, Stephen J.; Hofer, John H.

    2009-02-01

    A laboratory testing program was developed to examine the mechanical behavior of salt from the Richton salt dome. The resulting information is intended for use in design and evaluation of a proposed Strategic Petroleum Reserve storage facility in that dome. Core obtained from the drill hole MRIG-9 was obtained from the Texas Bureau of Economic Geology. Mechanical properties testing included: (1) acoustic velocity wave measurements; (2) indirect tensile strength tests; (3) unconfined compressive strength tests; (4) ambient temperature quasi-static triaxial compression tests to evaluate dilational stress states at confining pressures of 725, 1450, 2175, and 2900 psi; and (5) confined triaxial creep experiments to evaluate the time-dependent behavior of the salt at axial stress differences of 4000 psi, 3500 psi, 3000 psi, 2175 psi and 2000 psi at 55 C and 4000 psi at 35 C, all at a constant confining pressure of 4000 psi. All comments, inferences, discussions of the Richton characterization and analysis are caveated by the small number of tests. Additional core and testing from a deeper well located at the proposed site is planned. The Richton rock salt is generally inhomogeneous as expressed by the density and velocity measurements with depth. In fact, we treated the salt as two populations, one clean and relatively pure (> 98% halite), the other salt with abundant (at times) anhydrite. The density has been related to the insoluble content. The limited mechanical testing completed has allowed us to conclude that the dilatational criteria are distinct for the halite-rich and other salts, and that the dilation criteria are pressure dependent. The indirect tensile strengths and unconfined compressive strengths determined are consistently lower than other coastal domal salts. The steady-state-only creep model being developed suggests that Richton salt is intermediate in creep resistance when compared to other domal and bedded salts. The results of the study provide only

  3. Preliminary results from an integrated, multi-parameter, experiment at the Santiaguito lava dome complex, Guatemala

    Science.gov (United States)

    De Angelis, S.; Rietbrock, A.; Lavallée, Y.; Lamb, O. D.; Lamur, A.; Kendrick, J. E.; Hornby, A. J.; von Aulock, F. W.; Chigna, G.

    2016-12-01

    Understanding the complex processes that drive volcanic unrest is crucial to effective risk mitigation. Characterization of these processes, and the mechanisms of volcanic eruptions, is only possible when high-resolution geophysical and geological observations are available over comparatively long periods of time. In November 2014, the Liverpool Earth Observatory, UK, in collaboration with the Instituto Nacional de Sismologia, Meteorologia e Hidrologia (INSIVUMEH), Guatemala, established a multi-parameter geophysical network at Santiaguito, one of the most active volcanoes in Guatemala. Activity at Santiaguito throughout the past decade, until the summer of 2015, was characterized by nearly continuous lava dome extrusion accompanied by frequent and regular small-to-moderate gas or gas-and-ash explosions. Over the past two years our network collected a wealth of seismic, acoustic and deformation data, complemented by campaign visual and thermal infrared measurements, and rock and ash samples. Here we present preliminary results from the analysis of this unique dataset. Using acoustic and thermal data collected during 2014-2015 we were able to assess volume fractions of ash and gas in the eruptive plumes. The small proportion of ash inferred in the plumes confirms estimates from previous, independent, studies, and suggests that these events did not involve significant magma fragmentation in the conduit. The results also agree with the suggestion that sacrificial fragmentation along fault zones in the conduit region, due to shear-induced thermal vesiculation, may be at the origin of such events. Finally, starting in the summer of 2015, our experiment captured the transition to a new phase of activity characterized by vigorous vulcanian-style explosions producing large, ash-rich, plumes and frequent hazardous pyroclastic flows, as well as the formation a large summit crater. We present evidence of this transition in the geophysical and geological data, and discuss its

  4. Strong correlation of borehole optical backscattering and volcanic sulfate signatures at Siple Dome

    Science.gov (United States)

    Talghader, J.; Chan, W. S.; Mah, M.; Bay, R. C.

    2016-12-01

    A borehole logging instrument measuring optical backscattering was deployed at Siple Dome (SDMA) in January 2014. The logger body was a completely passive instrument consisting of a lightweight aluminum structure supporting two optical fiber cables and associated collimating connectors. One cable guided light from an 808 nm laser on the ice surface while the second collected backscattered light and guided it to a silicon detector, also on the surface. Both laser and detector were positioned within a few cm of one another for high resolution. An image of the device is shown in Figure 1. The laser wavelength was chosen so that the scattering length for light within the ice would be comparable to the absorption length. In this way it was possible to guarantee that most of the light received had been directly backscattered from sites within the ice rather than traveling for many meters through many scattering events, which would reduce the resolution of the layer measurement. The resolution of the measurement was estimated to be on the order of a centimeter to a few centimeters, the lower limit given by the size of the collimated laser beam and the other by the geometry of the laser-detector unit and the nature of the optical backscattering at 808 nm. The ice could not be sampled directly to determine the physical source of the scattering but, based on prior work at Siple Dome and other boreholes, the background signal was assumed to be produced by bubbles with the observed layer structure primarily due to volcanic ash. Useful data was measured to a depth of approximately 175 m, with the resulting signal given in Figure 2, minus the background scattering due to bubbles. 20 of the 27 statistically significant deviations from the background average matched closely with the volcanic sulfate record published by Kurbatov, et. al. in 2006 using the chronology of Taylor, et. al. in 2004. The correlation between optical backscattering, presumably from ash, and the presence of

  5. Establishing the Antarctic Dome C community reference standard site towards consistent measurements from Earth observation satellites

    Science.gov (United States)

    Cao, C.; Uprety, S.; Xiong, J.; Wu, A.; Jing, P.; Smith, D.; Chander, G.; Fox, N.; Ungar, S.

    2010-01-01

    Establishing satellite measurement consistency by using common desert sites has become increasingly more important not only for climate change detection but also for quantitative retrievals of geophysical variables in satellite applications. Using the Antarctic Dome C site (75°06′S, 123°21′E, elevation 3.2 km) for satellite radiometric calibration and validation (Cal/Val) is of great interest owing to its unique location and characteristics. The site surface is covered with uniformly distributed permanent snow, and the atmospheric effect is small and relatively constant. In this study, the long-term stability and spectral characteristics of this site are evaluated using well-calibrated satellite instruments such as the Moderate Resolution Imaging Spectroradiometer (MODIS) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS). Preliminary results show that despite a few limitations, the site in general is stable in the long term, the bidirectional reflectance distribution function (BRDF) model works well, and the site is most suitable for the Cal/Val of reflective solar bands in the 0.4–1.0 µm range. It was found that for the past decade, the reflectivity change of the site is within 1.35% at 0.64 µm, and interannual variability is within 2%. The site is able to resolve calibration biases between instruments at a level of ~1%. The usefulness of the site is demonstrated by comparing observations from seven satellite instruments involving four space agencies, including OrbView-2–SeaWiFS, Terra–Aqua MODIS, Earth Observing 1 (EO-1) – Hyperion, Meteorological Operational satellite programme (MetOp) – Advanced Very High Resolution Radiometer (AVHRR), Envisat Medium Resolution Imaging Spectrometer (MERIS) – dvanced Along-Track Scanning Radiometer (AATSR), and Landsat 7 Enhanced Thematic Mapper Plus (ETM+). Dome C is a promising candidate site for climate quality calibration of satellite radiometers towards more consistent satellite measurements, as part

  6. Multiple timescales of cyclical behaviour observed at two dome-forming eruptions

    Science.gov (United States)

    Lamb, Oliver D.; Varley, Nick R.; Mather, Tamsin A.; Pyle, David M.; Smith, Patrick J.; Liu, Emma J.

    2014-09-01

    Cyclic behaviour over a range of timescales is a well-documented feature of many dome-forming volcanoes, but has not previously been identified in high resolution seismic data from Volcán de Colima (Mexico). Using daily seismic count datasets from Volcán de Colima and Soufrière Hills volcano (Montserrat), this study explores parallels in the long-term behaviour of seismicity at two long-lived systems. Datasets are examined using multiple techniques, including Fast-Fourier Transform, Detrended Fluctuation Analysis and Probabilistic Distribution Analysis, and the comparison of results from two systems reveals interesting parallels in sub-surface processes operating at both systems. Patterns of seismicity at both systems reveal complex but broadly similar long-term temporal patterns with cycles on the order of ~ 50- to ~ 200-days. These patterns are consistent with previously published spectral analyses of SO2 flux time-series at Soufrière Hills volcano, and are attributed to variations in the movement of magma in each system. Detrended Fluctuation Analysis determined that both volcanic systems showed a systematic relationship between the number of seismic events and the relative ‘roughness' of the time-series, and explosions at Volcán de Colima showed a 1.5-2 year cycle; neither observation has a clear explanatory mechanism. At Volcán de Colima, analysis of repose intervals between seismic events shows long-term behaviour that responds to changes in activity at the system. Similar patterns for both volcanic systems suggest a common process or processes driving the observed signal but it is not clear from these results alone what those processes may be. Further attempts to model conduit processes at each volcano must account for the similarities and differences in activity within each system. The identification of some commonalities in the patterns of behaviour during long-lived dome-forming eruptions at andesitic volcanoes provides a motivation for

  7. Surface circulation and upwelling patterns around Sri Lanka and formation of the Sri Lanka Dome

    Science.gov (United States)

    Pattiaratchi, C. B.; Wijeratne, S.; De Vos, A.

    2014-12-01

    Sri Lanka, a relatively large island (length 440 km; width 225 km), occupies a unique location within the equatorial belt in the northern Indian Ocean with the Arabian Sea on its western side and the Bay of Bengal on its eastern side and experiences bi-annually reversing monsoon winds. This allows for the Island to interact with the seasonally reversing monsoon currents leading to the the island mass effect and enhanced primary production. We will present elements of the dynamics of the surface circulation and coastal upwelling in the waters around Sri Lanka using satellite imagery and numerical simulations using the Regional Ocean Modelling System (ROMS). The model was run for 4 years to examine the inter-annual, seasonal and shorter term (~10 days) variability. The results confirmed the presence of the reversing current system, between the equator and Sri Lanka, in response to the changing wind field: the eastward flowing Southwest Monsoon Current (SMC) during the Southwest (SW) monsoon transporting 11.5 Sv and the westward flowing Northeast Monsoon Current (NMC) transporting 9.5 Sv during the Northeast (NE) monsoon, respectively. A recirculation feature located to the east of Sri Lanka during the SW monsoon, the Sri Lanka Dome, is shown to result from the interaction between the SMC and the Island of Sri Lanka. Along the eastern and western coasts, during both monsoon periods, flow is southward converging along the south coast (see Figure). During the SW monsoon the Island deflects the eastward flowing SMC southward whilst along the east coast the southward flow results from the Sri Lanka Dome recirculation. The major upwelling region, during both monsoon periods, is located along the south coast resulting from southward flow converging along the south coast and subsequent divergence associated with the offshore transport of water(see Figure). Higher surface chlorophyll concentrations were observed during the SW monsoon. The location of the flow convergence and

  8. Features in air ions measured by an air ion spectrometer (AIS) at Dome C

    Science.gov (United States)

    Chen, Xuemeng; Virkkula, Aki; Kerminen, Veli-Matti; Manninen, Hanna E.; Busetto, Maurizio; Lanconelli, Christian; Lupi, Angelo; Vitale, Vito; Del Guasta, Massimo; Grigioni, Paolo; Väänänen, Riikka; Duplissy, Ella-Maria; Petäjä, Tuukka; Kulmala, Markku

    2017-11-01

    An air ion spectrometer (AIS) was deployed for the first time at the Concordia station at Dome C (75°06' S, 123°23' E; 3220 m a. s. l. ), Antarctica during the period 22 December 2010-16 November 2011 for measuring the number size distribution of air ions. In this work, we present results obtained from this air ion data set together with aerosol particle and meteorological data. The main processes that modify the number size distribution of air ions during the measurement period at this high-altitude site included new particle formation (NPF, observed on 85 days), wind-induced ion formation (observed on 36 days), and ion production and loss associated with cloud/fog formation (observed on 2 days). For the subset of days when none of these processes seemed to operate, the concentrations of cluster ions (0.9-1.9 nm) exhibited a clear seasonality, with high concentrations in the warm months and low concentrations in the cold. Compared to event-free days, days with NPF were observed with higher cluster ion concentrations. A number of NPF events were observed with restricted growth below 10 nm, which were termed as suppressed NPF. There was another distinct feature, namely a simultaneous presence of two or three separate NPF and subsequent growth events, which were named as multi-mode NPF events. Growth rates (GRs) were determined using two methods: the appearance time method and the mode fitting method. The former method seemed to have advantages in characterizing NPF events with a fast GR, whereas the latter method is more suitable when the GR was slow. The formation rate of 2 nm positive ions (J2+) was calculated for all the NPF events for which a GR in the 2-3 nm size range could be determined. On average, J2+ was about 0.014 cm-3 s-1. The ion production in relation to cloud/fog formation in the size range of 8-42 nm seemed to be a unique feature at Dome C, which has not been reported elsewhere. These ions may, however, either be multiply charged particles but

  9. AIRS Observations of DomeC in Antarctica and Comparison with Automated Weather Stations (AWS)

    Science.gov (United States)

    Aumann, Hartmut H.; Gregorich, Dave; Broberg, Steve

    2006-01-01

    We compare the surface temperatures at Dome Concordia (DomeC) deduced from AIRS data and two Automatic Weather Stations at Concordia Station: AWS8989 , which has been in operation since December 1996, and AWS.it, for which data are available between January and November 2005. The AWS8989 readings are on average 3 K warmer than the AWS.it readings, with a warmer bias in the Antarctic summer than in the winter season. Although AIRS measures the skin brightness temperature, while the AWS reports the temperature of the air at 3 meter above the surface, the AIRS measurements agree well with the AWS.it readings for all data and separately for the summer and winter seasons, if data taken in the presence of strong surface inversions are filtered out. This can be done by deducing the vertical temperature gradient above the surface directly from the AIRS temperature sounding channels or indirectly by noting that extreme vertical gradients near the surface are unlikely if the wind speed is more than a few meters per second. Since the AIRS measurements are very well calibrated, the agreement with AWS.it is very encouraging. The warmer readings of AWS8989 are likely due to thermal contamination of the AWS8989 site by the increasing activity at Concordia Station. Data from an AWS.it quality station could be used for the evaluation of radiometric accuracy and stability of polar orbiting sounders at low temperatures. Unfortunately, data from AWS.it was available only for a limited time. The thermal contamination of the AWS8989 data makes long-term trends deduced from AWS8989 and possibly results about the rapid Antarctic warming deduced from other research stations on Antarctica suspect. AIRS is the first hyperspectral infrared sounder designed in support of weather forecasting and climate research. It was launched in May 2002 on the EOS Aqua spacecraft into a 704 km altitude polar sun-synchronous orbit. The lifetime of AIRS, estimated before launch to be at least 5 years is

  10. Salinity management in southern Italy irrigation areas

    Directory of Open Access Journals (Sweden)

    Massimo Monteleone

    Full Text Available After a synthetic review of the most worrisome pressures applied over soils and waters, general criterions and normative principles that have to lead the technical intervention on soil and water protection are accounted, both with respect to farm activity and land planning. The salinity problem is faced, then, through the analysis of the nature and origin of saline soil and of the complex quantitative relationships able to interpret the accumulation and leaching of soil salts. Having specified the theoretical bases of salinity, the related technical features are then considered in order to define a proper management of soil and waters. Particular relevance is assigned to the irrigation and leaching techniques as well as, more briefly, to other agronomic interventions in order to guarantee the most effective salinity control. Another relevant technical facet of salinity control, although quite often neglected or retained of secondary importance in comparison to irrigation, is the drainage and disposal of leached water. The increased sensibility on the environmental impacts that the disposal of these waters can produce has raised today the level of attention on these procedures that are disciplined by norms of law and, therefore, require appropriate techniques of intervention. Finally, after the different scale orders involved in the management of salinity are defined (from the field and farm level up to the land and basin, the fundamental elements in order to work out a risk analysis and an action program are illustrated; some indications about the most up to date salinity monitoring and mapping methods are also provided, considering their great importance to continuously check the possible broadening of salinization and to carefully maintain its control.

  11. Treating nahcolite containing formations and saline zones

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J

    2013-06-11

    A method for treating a nahcolite containing subsurface formation includes removing water from a saline zone in or near the formation. The removed water is heated using a steam and electricity cogeneration facility. The heated water is provided to the nahcolite containing formation. A fluid is produced from the nahcolite containing formation. The fluid includes at least some dissolved nahcolite. At least some of the fluid is provided to the saline zone.

  12. High volume normal saline alone is as effective as nebulized salbutamol-normal saline, epinephrine-normal saline, and 3% saline in mild bronchiolitis.

    Science.gov (United States)

    Anil, Ayse Berna; Anil, Murat; Saglam, Ayse Bircan; Cetin, Nevin; Bal, Alkan; Aksu, Nejat

    2010-01-01

    The objective of this study was to investigate the effectivenesses of nebulized salbutamol, epinephrin, 3% saline, and normal saline (0.9% NaCl) in the treatment of mildly affected infants with acute bronchiolitis. We enrolled 186 children (mean age 9.5 +/- 5.3 months, range 1.5-24 months, 65.1% male) with a first episode of wheezing diagnosed as mild bronchiolitis in emergency department. Patients were randomized in a double-blind fashion to receive 4 ml dose either of 1.5 mg epinephrine plus normal saline (group 1; n = 38) or 1.5 mg epinephrine plus 3% saline (group 2; n = 39) or 2.5 mg salbutamol plus normal saline (group 3; n = 36) or 2.5 mg salbutamol plus 3% saline (group 4; n = 36) or normal saline alone (group 5; n = 37) at 0 and 30 min. Thus, all treatment modalities included high amount of NaCl (72-240 mg). Clinical score, oxygen saturation and heart rate were assessed at 0, 30, 60, and 120 min. After discharge, patients were reassessed by telephone contact at 48 hr and 6 months. The baseline characteristics were similar in all groups (P > 0.05). The outcome of patients at 120 min was found significantly better than the baseline values (P 0.05). No adverse effects attributable to nebulized therapy were seen. In conclusion, all treatment modalities used in this study, including a total of 8 ml normal saline inhalation at 30-min interval showed clinically significant and swift improvement in mildly affected ambulatory infants with acute bronchiolitis. (c) 2009 Wiley-Liss, Inc.

  13. Microstrip Patch Sensor for Salinity Determination

    Directory of Open Access Journals (Sweden)

    Kibae Lee

    2017-12-01

    Full Text Available In this paper, a compact microstrip feed inset patch sensor is proposed for measuring the salinities in seawater. The working principle of the proposed sensor depends on the fact that different salinities in liquid have different relative permittivities and cause different resonance frequencies. The proposed sensor can obtain better sensitivity to salinity changes than common sensors using conductivity change, since the relative permittivity change to salinity is 2.5 times more sensitive than the conductivity change. The patch and ground plane of the proposed sensor are fabricated by conductive copper spray coating on the masks made by 3D printer. The fabricated patch and the ground plane are bonded to a commercial silicon substrate and then attached to 5 mm-high chamber made by 3D printer so that it contains only 1 mL seawater. For easy fabrication and testing, the maximum resonance frequency was selected under 3 GHz and to cover salinities in real seawater, it was assumed that the salinity changes from 20 to 35 ppt. The sensor was designed by the finite element method-based ANSYS high-frequency structure simulator (HFSS, and it can detect the salinity with 0.01 ppt resolution. The designed sensor has a resonance frequency separation of 37.9 kHz and reflection coefficients under −20 dB at the resonant frequencies. The fabricated sensor showed better performance with average frequency separation of 48 kHz and maximum reflection coefficient of −35 dB. By comparing with the existing sensors, the proposed compact and low-cost sensor showed a better detection capability. Therefore, the proposed patch sensor can be utilized in radio frequency (RF tunable sensors for salinity determination.

  14. Sea Surface Salinity : Research Challenges and Opportunities

    Science.gov (United States)

    Halpern, David; Lagerloef, Gary; Font, Jordi

    2012-01-01

    Sea surface salinity (SSS) can be important in regulating sea surface temperature (SST). Two technological breakthrough satellite SSS missions, Aquarius and Soil Moisture and Ocean Salinity (SMOS), are currently producing high-quality SSS data. This paper provides an overview of the importance of SSS for weather and climate applications and describes the Aquarius and SMOS missions. The newness of adequately sampled SSS data prompted a first-time at-sea field campaign devoted to improved understanding of SSS variations.

  15. Microstrip Patch Sensor for Salinity Determination.

    Science.gov (United States)

    Lee, Kibae; Hassan, Arshad; Lee, Chong Hyun; Bae, Jinho

    2017-12-18

    In this paper, a compact microstrip feed inset patch sensor is proposed for measuring the salinities in seawater. The working principle of the proposed sensor depends on the fact that different salinities in liquid have different relative permittivities and cause different resonance frequencies. The proposed sensor can obtain better sensitivity to salinity changes than common sensors using conductivity change, since the relative permittivity change to salinity is 2.5 times more sensitive than the conductivity change. The patch and ground plane of the proposed sensor are fabricated by conductive copper spray coating on the masks made by 3D printer. The fabricated patch and the ground plane are bonded to a commercial silicon substrate and then attached to 5 mm-high chamber made by 3D printer so that it contains only 1 mL seawater. For easy fabrication and testing, the maximum resonance frequency was selected under 3 GHz and to cover salinities in real seawater, it was assumed that the salinity changes from 20 to 35 ppt. The sensor was designed by the finite element method-based ANSYS high-frequency structure simulator (HFSS), and it can detect the salinity with 0.01 ppt resolution. The designed sensor has a resonance frequency separation of 37.9 kHz and reflection coefficients under -20 dB at the resonant frequencies. The fabricated sensor showed better performance with average frequency separation of 48 kHz and maximum reflection coefficient of -35 dB. By comparing with the existing sensors, the proposed compact and low-cost sensor showed a better detection capability. Therefore, the proposed patch sensor can be utilized in radio frequency (RF) tunable sensors for salinity determination.

  16. PRODUCTION OF TOMATO SEEDLINGS UNDER SALINE IRRIGATION

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Brasiliano Campos

    2007-01-01

    Full Text Available Processing tomato is the most important vegetable crop of the Brazilian agribusiness and few researches have been conducted to evaluate the tolerance of this crop to saline stress. In this study, the effects of five levels of salinity of the irrigation water (1, 2, 3, 4 and 5 dS m-1 and three equivalent proportions of Na:Ca:Mg (1:1:0.5, 4:1:0.5 and 7:1:0.5 were tested on the emergence and vigor of processing tomato, cultivar IPA 6. Seeds were sowed in expanded polystyrene tray (128 cells and each tray received 1 L of water after sowing. The trays were piled and, four days after sowing, they were placed on suspended supports in a greenhouse. Irrigation was accomplished daily from the fifth day after sowing. Only dry weight of shoot and root was affected by sodium proportions, while linear reductions of the speed of emergence, stem length and the dry weight of shoot and root were observed with increasing salinity. Root was more affected than shoot by salinity and relative growth ratioincreased with salinity levels on the 14-21 days after sowing period, indicating that the crop showed a certain increase of salinity tolerance with the time of exposure to salts.

  17. Assessment of Halophyte Growth in Saline Environments

    Science.gov (United States)

    Garrett, A.; Stracke, S.; Nowak, B.; Goehring, N.; Saito, L.; Verburg, P.

    2016-12-01

    Salinization of soil and water can pose a serious threat for irrigated agricultural lands in arid and semi-arid regions as high concentrations of salt negatively impacts crop production and, consequently, the agricultural economy. Highly salt-tolerant plants, or halophytes, may provide a viable option for saline areas, enabling economic production from previously unproductive land. Many halophytes can be used for human consumption, forage for livestock, or biofuel production. These plants may also remediate saline soils by taking up the salt from the soil, thereby improving conditions for conventional crop cultivation. This project aims to determine halophyte growth under different salt stresses. Two halophytic crops, AC Saltlander green wheatgrass (Elymus hoffmannii) and Rainbow quinoa (Chenopodium quinoa var. rainbow), were cultivated in a greenhouse with saline soil treatments (2, 4, 6, 8 and 12 dS/m) and saline irrigation treatments (1, 2, 4, and 6 dS/m), resulting in 20 different treatment combinations. Plant characteristics such as leaf area, number of tillers and branches, and leaf height were measured until harvest. A subset of harvested biomass (inflorescences, stems, leaves, and roots) and soil subsamples were analyzed for nutrient and salt content to determine relationships between salinity treatments, aboveground and belowground biomass, and nutrient content. Results from this experiment will be used to help parametrize models simulating different management scenarios for a variety of halophytic species.

  18. High salinity anomalies south of Oahu, Hawaii

    Science.gov (United States)

    Pearson, K.; Carter, G. S.

    2013-12-01

    Patches of higher salinity water were observed, using Seaglider data, in the upper 50m of the water-column between Oahu and Penguin Bank. These anomalies occur approximately once a month, and are visible in the glider data for an average of 3 days. Anomalies have abrupt transitions occurring over mere hours. Salinity within the patches can reach values in excess of 35.2 psu, 0.3 higher than the average profile for the region. The salinity signature associated with the anomalies corresponds to Subtropical surface water, found north of the Hawaiian island chain. The high salinity water is trapped by the thermocline in the mixed layer. Seasonal variations of the anomaly depth are directly related to the seasonal variations of mixed layer depth. These patches of high salinity coincide with the presence of eddies. Using sea surface height as an indicator, we found that eddy-eddy interaction and eddy-island interaction dictate the advection of upwelled waters into the region. Infrequently, we observe corresponding temperature anomalies. The larger the distance between the center of the eddy and the glider, the less visible the temperature anomaly. Positive (negative) values indicate salinity above (below) the mean profile.

  19. Normal Saline Versus Hypertonic 3% Saline: It’s Efficacy in Non-Acute Rhinosinusitis

    Directory of Open Access Journals (Sweden)

    Nezamoddin Berjis

    2011-01-01

    Full Text Available Introduction: Sinusitis is one of the most common diseases in general and in otolaryngology practice, but the optimal therapeutic options have not yet been fully developed. This manuscript will try to compare normal saline nasal douching with hypertonic saline in reducing symptoms and improving its signs. Materials and Methods: One hundred and fourteen patients suffering from non acute rhinosinusitis, documented by history, physical examination and radiologic studies were divided into normal saline and hypertonic saline groups, each consisting of 57 patients. data were obtained by physical examination and a questionnaire.. Results:  Type of treatment had no significant effect on headache, morning dryness of mouth and pharynx and fatigue. Nontheless, nasal congestion, purulent discharge and postnasal discharge were reported to have improved in the group treated with hypertonic saline versus the normal saline group. Patient satisfaction also showed better scores in the hypertonic saline group. Conclusion: Hypertonic saline (3% is more effective for nasal irrigation  than normal saline in chronic rhinosinusitis.

  20. The Upper Miocene of the Rostov Dome (Eastern Paratethys: Implication of the chronostratigraphy and bivalvia-based biostratigraphy

    Directory of Open Access Journals (Sweden)

    Ruban Dmitry A.

    2005-01-01

    Full Text Available The Rostov Dome is located in the south of the Russian Platform. In the Late Miocene this area was embraced by the Eastern Paratethys. The implications of a recently developed Neogene chronostratigraphy to the studied area are discussed. The Sarmatian regional stage corresponds to the upper part of the Langhian, the entire Serravalian and the lower part of the Tortonian global stages; the Maeotian regional stage corresponds to the upper part of the Tortonian and the lowermost horizons of the Messinian global stages; the Pontian regional stage corresponds to most of the Messinian and the lowermost Zanclean global stages. A first Bivalvia-based bio-stratigraphic framework is proposed for the territory of the Rostov Dome. Five biozones were established within the Serravalian-Messinian: Tapes vitalianus, Cerastoderma fittoni-Cerastoderma subfittoni, Congeria panticapaea, Congeria amygdaloides navicula and Monodacna pseudocatillus-Prosodacna schirvanica.

  1. Science Programs for a 2-m Class Telescope at Dome C, Antarctica: PILOT, the Pathfinder for an International Large Optical Telescope

    National Research Council Canada - National Science Library

    J. S. Lawrence; M. C. B. Ashley; J. A. Bailey; C. Blake; T. R. Bedding; J. Bland-Hawthorn; I. A. Bond; K. Glazebrook; M. G. Hidas; G. Lewis; S. N. Longmore; S. T. Maddison; S. Mattila; V. Minier; S. D. Ryder; R. Sharp; C. H. Smith; J. W. V. Storey; C. G. Tinney; P. Tuthill; A. J. Walsh; W. Walsh; M. Whiting; T. Wong; D. Woods; P. C. M. Yock

    2005-01-01

    .... Pathfinder for an International Large Optical Telescope (PILOT) is a proposed 2 m telescope, to be built at Dome C in Antarctica, able to exploit these conditions for conducting astronomy at optical and infrared wavelengths...

  2. The influence of the synoptic regime on stable water isotopes in precipitation at Dome C, East Antarctica

    Science.gov (United States)

    Schlosser, Elisabeth; Dittmann, Anna; Stenni, Barbara; Powers, Jordan G.; Manning, Kevin W.; Masson-Delmotte, Valérie; Valt, Mauro; Cagnati, Anselmo; Grigioni, Paolo; Scarchilli, Claudio

    2017-10-01

    The correct derivation of paleotemperatures from ice cores requires exact knowledge of all processes involved before and after the deposition of snow and the subsequent formation of ice. At the Antarctic deep ice core drilling site Dome C, a unique data set of daily precipitation amount, type, and stable water isotope ratios is available that enables us to study in detail atmospheric processes that influence the stable water isotope ratio of precipitation. Meteorological data from both automatic weather station and a mesoscale atmospheric model were used to investigate how different atmospheric flow patterns determine the precipitation parameters. A classification of synoptic situations that cause precipitation at Dome C was established and, together with back-trajectory calculations, was utilized to estimate moisture source areas. With the resulting source area conditions (wind speed, sea surface temperature, and relative humidity) as input, the precipitation stable isotopic composition was modeled using the so-called Mixed Cloud Isotope Model (MCIM). The model generally underestimates the depletion of 18O in precipitation, which was not improved by using condensation temperature rather than inversion temperature. Contrary to the assumption widely used in ice core studies, a more northern moisture source does not necessarily mean stronger isotopic fractionation. This is due to the fact that snowfall events at Dome C are often associated with warm air advection due to amplification of planetary waves, which considerably increases the site temperature and thus reduces the temperature difference between source area and deposition site. In addition, no correlation was found between relative humidity at the moisture source and the deuterium excess in precipitation. The significant difference in the isotopic signal of hoarfrost and diamond dust was shown to disappear after removal of seasonality. This study confirms the results of an earlier study carried out at Dome

  3. The Fulldome Curriculum for the Spitz SciDome Digital Planetarium: A New Age for Planetarium Education

    Science.gov (United States)

    Bradstreet, David H.; Huggins, S. L.

    2010-01-01

    Astronomy education received a huge boost from the Space Program in the 1960's and early 1970's as evidenced by a large increase in school planetariums built nationwide at that time. But with the waning of manned explorations so also went the push for astronomy in the schools, and many school planetariums are underutilized or not used at all. This poster will discuss and illustrate some of the new Fulldome Curriculum that has been developed specifically for the Spitz SciDome digital planetarium powered by Starry Night. It is now possible to teach astronomical concepts in new and exciting ways and present topics that were extremely difficult to convey to lay audiences in the past. One of the strongest advantages of the SciDome is that, since it uses Starry Night as its astronomical engine, students can create their own astronomical configurations in the computer lab or at home using the PC or Mac version and then simply load them onto the SciDome planetarium system and display them for the class on the dome. Additionally, the instructor can create artificial bodies to pose "What if” scenarios, for example, "What would the Moon look like if it didn't rotate synchronously?", or "What would the analemma look like if the Earth's orbit were circular and not an ellipse?" Topics covered in the series include The Moon, Seasons, Coordinate Systems, Roemer's Method of Measuring the Speed of Light, Analemmas in the Solar System, Precession, Mimas and the Cassini Division, Halley's Comet in 1910, Dog Days, Galactic Distributions of Celestial Bodies, Retrograde Paths of Mars, Mercury's Orbit and the Length of the Mercurian Day, Altitude of the North Celestial Pole, Why Polaris Appears Mostly Stationary, Circumpolar Contellations, Planet Definition, Scale of the Solar System, Stonehenge, The Changing Aspect of Saturn's Appearance and Scorpio's Claws.

  4. Formation of Sclerotic Hydrate Deposits in a Pipe for Extraction of a Gas from a Dome Separator

    Science.gov (United States)

    Urazov, R. R.; Chiglinstev, I. A.; Nasyrov, A. A.

    2017-09-01

    The theory of formation of hydrate deposits on the walls of a pipe for extraction of a gas from a dome separator designed for the accident-related collection of hydrocarbons on the ocean floor is considered. A mathematical model has been constructed for definition of a steady movement of a gas in such a pipe with gas-hydrate deposition under the conditions of changes in the velocity, temperature, pressure, and moisture content of the gas flow.

  5. SNOW SURFACE FEATURES ALONG THE TRAVERSE ROUTE FROM THE COAST TO DOME FUJI STATION, QUEEN MAUD LAND, ANTARCTICA

    OpenAIRE

    フルカワ, テルオ; カミヤマ, コキチ; マエノ, ヒデオ; Teruo, Furukawa; Kokichi, Kamiyama; Hideo, MAENO

    1996-01-01

    Frequencies of snow surface features such as sastrugi, dunes and thermal cracks were measured along the traverse route from the coastal region to the summit of the Queen Maud Land ice sheet, Dome Fuji Station, East Antarctica. The study route can be clearly divided into three regions on the basis of the regional characteristics of snow surface features : coastal region, katabatic wind region and inland plateau region. The coastal region is characterized by high frequency of small sastrugi and...

  6. The influence of the synoptic regime on stable water isotopes in precipitation at Dome C, East Antarctica

    Directory of Open Access Journals (Sweden)

    E. Schlosser

    2017-10-01

    Full Text Available The correct derivation of paleotemperatures from ice cores requires exact knowledge of all processes involved before and after the deposition of snow and the subsequent formation of ice. At the Antarctic deep ice core drilling site Dome C, a unique data set of daily precipitation amount, type, and stable water isotope ratios is available that enables us to study in detail atmospheric processes that influence the stable water isotope ratio of precipitation. Meteorological data from both automatic weather station and a mesoscale atmospheric model were used to investigate how different atmospheric flow patterns determine the precipitation parameters. A classification of synoptic situations that cause precipitation at Dome C was established and, together with back-trajectory calculations, was utilized to estimate moisture source areas. With the resulting source area conditions (wind speed, sea surface temperature, and relative humidity as input, the precipitation stable isotopic composition was modeled using the so-called Mixed Cloud Isotope Model (MCIM. The model generally underestimates the depletion of 18O in precipitation, which was not improved by using condensation temperature rather than inversion temperature. Contrary to the assumption widely used in ice core studies, a more northern moisture source does not necessarily mean stronger isotopic fractionation. This is due to the fact that snowfall events at Dome C are often associated with warm air advection due to amplification of planetary waves, which considerably increases the site temperature and thus reduces the temperature difference between source area and deposition site. In addition, no correlation was found between relative humidity at the moisture source and the deuterium excess in precipitation. The significant difference in the isotopic signal of hoarfrost and diamond dust was shown to disappear after removal of seasonality. This study confirms the results of an earlier study

  7. Design solutions for dome and main structure (mount) of giant telescopes

    Science.gov (United States)

    Murga, Gaizka; Bilbao, Armando; de Bilbao, Lander; Lorentz, Thomas E.

    2016-07-01

    During the last recent years, designs for several giant telescopes ranging from 20 to 40m in diameter are being developed: European Extremely Large Telescope Telescope (TMT). (E-ELT), Giant Magellan Telescope (GMT) and Thirty Meter It is evident that simple direct up-scaling of solutions that were more or less successful in the 8 to 10m class telescopes can not lead to viable designs for the future giant telescopes. New solutions are required to provide adequate load sharing, to cope with the large-scale derived deflections and to provide the required compliance, or to respond to structure-mechanism control interaction issues, among others. From IDOM experience in the development of the Dome and Main Structure of the European Extremely Large Telescope and our participation in some other giant telescopes, this paper reviews several design approaches for the main mechanisms and key structural parts of enclosures and mounts/main structures for giant telescopes, analyzing pros and cons of the different alternatives and outlining the preferred design schemes. The assessment is carried out mainly from a technical and performance-based angle but it also considers specific logistical issues for the assembly of these large telescopes in remote and space-limited areas, together with cost and schedule related issues.

  8. Petrogenesis of low Silica Adakitic domes of Sahl (South of Shahrood, southeast of Semnan Province

    Directory of Open Access Journals (Sweden)

    Fazilat Yousefi

    2016-12-01

    Full Text Available Sahl area, in the south of Shahrood, is a part of the northern portion of the Central Iran Structural Zone. The area is dominated by a thick sequence of the Paleocene to the middle Eocene volcanic and volcano-sedimentary rocks. Hypabyssal igneous rocks as dome, dike and sill with trachybasaltic andesite and trachyandesite composition intruded the sequence. Various enclaves with amphibolitic, gneissic, hornblenditic, pyroxenitic, tonalitic, gabbroic, tuffaceous sandstone and siltstone nature with different sizes and shapes are present in the rocks studied which can be taken as an evidence of contamination and magma mixing processes. With respect to geochemical characteristics, the studied rocks are belonging to low silica adakites , with calc-alkaline to high potassium calc-alkaline affinity, enriched in LREE and LILE and depleted in HREE and HSFE. Overall, the mentioned adakites resulted from crystallization of melts originated from partial melting of metasomatized or modified mantle wedge, above the subduction zone of the Neotethys oceanic slab (Sabzevar - Daruneh branch.

  9. Multi-Contrast Imaging and Digital Refocusing on a Mobile Microscope with a Domed LED Array.

    Directory of Open Access Journals (Sweden)

    Zachary F Phillips

    Full Text Available We demonstrate the design and application of an add-on device for improving the diagnostic and research capabilities of CellScope--a low-cost, smartphone-based point-of-care microscope. We replace the single LED illumination of the original CellScope with a programmable domed LED array. By leveraging recent advances in computational illumination, this new device enables simultaneous multi-contrast imaging with brightfield, darkfield, and phase imaging modes. Further, we scan through illumination angles to capture lightfield datasets, which can be used to recover 3D intensity and phase images without any hardware changes. This digital refocusing procedure can be used for either 3D imaging or software-only focus correction, reducing the need for precise mechanical focusing during field experiments. All acquisition and processing is performed on the mobile phone and controlled through a smartphone application, making the computational microscope compact and portable. Using multiple samples and different objective magnifications, we demonstrate that the performance of our device is comparable to that of a commercial microscope. This unique device platform extends the field imaging capabilities of CellScope, opening up new clinical and research possibilities.

  10. Multi-Contrast Imaging and Digital Refocusing on a Mobile Microscope with a Domed LED Array.

    Science.gov (United States)

    Phillips, Zachary F; D'Ambrosio, Michael V; Tian, Lei; Rulison, Jared J; Patel, Hurshal S; Sadras, Nitin; Gande, Aditya V; Switz, Neil A; Fletcher, Daniel A; Waller, Laura

    2015-01-01

    We demonstrate the design and application of an add-on device for improving the diagnostic and research capabilities of CellScope--a low-cost, smartphone-based point-of-care microscope. We replace the single LED illumination of the original CellScope with a programmable domed LED array. By leveraging recent advances in computational illumination, this new device enables simultaneous multi-contrast imaging with brightfield, darkfield, and phase imaging modes. Further, we scan through illumination angles to capture lightfield datasets, which can be used to recover 3D intensity and phase images without any hardware changes. This digital refocusing procedure can be used for either 3D imaging or software-only focus correction, reducing the need for precise mechanical focusing during field experiments. All acquisition and processing is performed on the mobile phone and controlled through a smartphone application, making the computational microscope compact and portable. Using multiple samples and different objective magnifications, we demonstrate that the performance of our device is comparable to that of a commercial microscope. This unique device platform extends the field imaging capabilities of CellScope, opening up new clinical and research possibilities.

  11. BaR-SPOrt: the instrument to be accommodated at Dome C

    Science.gov (United States)

    Zannoni, M.; Carretti, E.; Cortiglioni, S.; Macculi, C.; Ramponi, M.; Sbarra, C.; Ventura, G.; Monari, J.; Poloni, M.; Poppi, S.; Natale, V.; Nesti, R.; Baralis, M.; Peverini, O.; Tascone, R.; Virone, G.; Boscaleri, A.; Boella, G.; Sironi, G.; Gervasi, M.; de Bernardis, P.; Masi, S.; de Petris, M.

    The BaR-SPOrt (Balloon-Borne Radiometers for Sky Polarization Observations) experiment, a program of the Agenzia Spaziale Italiana (ASI) co-funded by PNRA (Progetto Nazionale di Ricerca in Antartide) was originally designed as a payload for long duration balloons flights. The changing scenario, both scientific and strategic, has led us to propose it for the starting winter campaign of at the Concordia Base. Here the instrument and the features making it suitable to operate at Dome-C are described. After the initial setup, BaR-SPOrt should not require any kind of routine intervention by a dedicated base staff. The experiment will just need electrical power (less than 2 kW) and a suitable accommodation on the field. It can be fully monitored and controlled, including the data acquisition, through its own telemetry/telecommand link using IRIDIUM modems. Both the receiver and the critical electronics are housed inside a temperature-controlled vacuum chamber, providing the properly stabilized environment. The cold part of the radiometer employs a closed loop mechanical cryo-cooler that provides temperatures <70 ±0.1 K with low power consumption (<200 W).

  12. Postural Control Disturbances Produced By Exposure to HMD and Dome Vr Systems

    Science.gov (United States)

    Harm, D. L.; Taylor, L. C.

    2005-01-01

    Two critical and unresolved human factors issues in VR systems are: 1) potential "cybersickness", a form of motion sickness which is experienced in virtual worlds, and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Most astronauts and cosmonauts experience perceptual and sensorimotor disturbances during and following space flight. All astronauts exhibit decrements in postural control following space flight. It has been suggested that training in virtual reality (VR) may be an effective countermeasure for minimizing perceptual and/or sensorimotor disturbances. People adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, and experimentally-produced stimulus rearrangements (e.g., reversing prisms, magnifying lenses, flight simulators, and VR systems). Adaptation is revealed by aftereffects including perceptual disturbances and sensorimotor control disturbances. The purpose of the current study was to compare disturbances in postural control produced by dome and head-mounted virtual environment displays. Individuals recovered from motion sickness and the detrimental effects of exposure to virtual reality on postural control within one hour. Sickness severity and initial decrements in postural equilibrium decreases over days, which suggests that subjects become dual-adapted over time. These findings provide some direction for developing training schedules for VR users that facilitate adaptation, and address safety concerns about aftereffects.

  13. Design of a segmented nonimaging Fresnel dome for nontracking solar collection

    Science.gov (United States)

    Viera-González, Perla M.; Sánchez-Guerrero, Guillermo E.; Martínez-Guerra, Edgar; Ceballos-Herrera, Daniel E.

    2017-07-01

    The efficiency of sunlight collection systems is related to the optical element used as a collector. On this subject, the design of a nontracking solar collector that consists of a segmented nonimaging Fresnel dome is presented. It is formed by the conjunction of different zones for solar collection, where each one is a nonimaging Fresnel lens that collects a specific angular range (θ) of sunlight received in the northeast of Mexico, but the methodology presented can be easily extended to other geographic locations. The final design is a semistationary segmented collector with a 100-cm diameter and 50-cm focal length that needs a 180-deg rotation over the XY-plane in each equinox. The numerical simulations show that the nontracking segmented collector has a combined acceptance semiangle of θ=±105 deg with an average efficiency of over 67% from 9:00 to 18:00 h. The spatial and angular distributions of the sunlight collected are also included. This design has a collection area equal to that of a single nonimaging Fresnel lens with an acceptance semiangle of θ=±45 deg. These results are reproducible and provide valuable data for designing nontracking solar collectors based on nonimaging Fresnel lens.

  14. Comparison of Clinical Features in Highly Myopic Eyes with and without a Dome-Shaped Macula.

    Science.gov (United States)

    Liang, I-Chia; Shimada, Noriaki; Tanaka, Yuichiro; Nagaoka, Natsuko; Moriyama, Muka; Yoshida, Takeshi; Ohno-Matsui, Kyoko

    2015-08-01

    To compare the clinical features of highly myopic eyes with a dome-shaped macula (DSM) with those without a DSM and to identify the funduscopic clues to suspect the presence of DSM. Retrospective case series. A total of 586 patients (1118 eyes) with high myopia (refractive error 50 μm in the vertical OCT image. Fundus photographs also were analyzed to identify the funduscopic clues to suspect the presence of DSM. The rate of DSM in 1118 highly myopic eyes. The rate of DSM in highly myopic eyes with macular complications. Funduscopic features to suggest the presence of DSM. Among the 1118 eyes, 225 (20.1%) had a DSM. A DSM was present in both vertical and horizontal OCT sections in 20% of eyes, along only the vertical section in 77% of eyes, and in only the horizontal section in 2% of eyes. The results of multiple regression analyses showed that serous retinal detachment and foveal and extrafoveal retinoschisis were significantly associated with the presence of DSM and that choroidal neovascularization was not. Ophthalmoscopically, 91.4% of the eyes with the appearance of a horizontal ridge connecting the optic disc and the fovea had a DSM. A DSM is found in as many as 20% of highly myopic individuals. Horizontal ridges connecting the optic disc and the fovea might be an important clue to suspect the presence of a DSM on the basis of fundus photographs. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  15. Monitoring of gaseous elemental mercury in central Antarctica at Dome Concordia

    Directory of Open Access Journals (Sweden)

    Dommergue A.

    2013-04-01

    Full Text Available Within the framework of the Global Mercury Observation System (GMOS, we are monitoring gaseous elemental mercury (Hg(0 at the Dome Concordia Station to improve our understanding of atmospheric Hg in the Antarctic atmosphere. This French-Italian facility is located in one of the coldest places on the planet and is situated on the vast Antarctic Plateau at an elevation of 3320 m. Continuous measurements began on December 7, 2011 and are ongoing. The median value calculated over the period (n=24506 is approximately 0.9 ng/m3 and values range from <0.1 ng/m3 up to 2.3 ng/m3. Preliminary results suggest that the Antarctic atmospheric boundary layer is a very reactive place during the periods when sunlight is present. A combination of fast and efficient oxidation processes with snow photochemistry lead to a dynamic record of Hg(0 unlike any other location. Our improved understanding of these processes will help to better constrain the cycle of Hg in the Southern Hemisphere.

  16. New Perspectives in Planetarium Lectures: How to Tell Science under the Dome while Preserving the "Enchantment"

    Science.gov (United States)

    Gandolfi, G.; Catanzaro, G.; Giovanardi, S.; Masi, G.; Vomero, V.

    2005-12-01

    We discuss the philosophy and strategy of a modern planetarium lecture within the larger frame of the communication of astronomy. The planetarium is a peculiar medium that requires a creative and rigorous approach in order to balance the three motivating forces behind the 'planetarium experience': scientific knowledge (method and contents); technological 'sense of wonder' and a pre-rational (not necessarily anti-rational) sense of 'enchantment'. While scientific and technological resources are typically fully exploited in state-of-the-art domes, the latter concept-introduced by Max Weber in order to categorize the mystic/aesthetic impact of nature on the human mind-has not been sufficiently explored. To use it effectively demands an understanding of the public perception of astronomy, stressing the crucial role of professional communication skills for the effective communication of science. Rather than enforcing a narrow focus on pure science and/or a crusade against astrology, we believe that the planetarium experience should be a stimulating reawakening of curiosity and a holistic awareness of the sky and hence of the Universe. Fine tuning of the above three components makes the classical confl ict between the boring academic lecture under the stars versus disneyish, supertechnological shows obsolete. We present some approaches for creating "fine-tuned lectures", with examples from our experience at the Rome Planetarium.

  17. In search of in-situ radiocarbon in Law Dome ice and firn

    CERN Document Server

    Smith, A M; Etheridge, D M; Lowe, D C; Hua, Q; Trudinger, C M; Zoppi, U; El-Cheikh, A

    2000-01-01

    Results of AMS radiocarbon measurements on CO and CO sub 2 separated from firn air directly pumped from the ice sheet, and on CO sub 2 separated from air extracted from ice cores by a dry grating technique, are presented. The firn air samples and ice cores used in this study were collected from the region of Law Dome, Antarctica. No evidence of in-situ sup 1 sup 4 CO sub 2 was found in the firn air samples or the ice core air samples from one site although a slight enhancement of sup 1 sup 4 CO above expected polar atmospheric concentrations was observed for some firn air samples. A clear in-situ sup 1 sup 4 CO sub 2 signal for ice pre-dating the radiocarbon bomb pulse was found, however, in air samples extracted from an ice core from a second site. We compare these results and propose an hypothesis to explain this apparent contradiction. The degree to which in-situ sup 1 sup 4 C is released from the ice crystals during trapping and bubble formation is considered and discussed. The selectivity of the dry grat...

  18. High-resolution boundary conditions of an old ice target near Dome C, Antarctica

    Directory of Open Access Journals (Sweden)

    D. A. Young

    2017-08-01

    Full Text Available A high-resolution (1 km line spacing aerogeophysical survey was conducted over a region near the East Antarctic Ice Sheet's Dome C that may hold a 1.5 Myr climate record. We combined new ice thickness data derived from an airborne coherent radar sounder with unpublished data that was in part unavailable for earlier compilations, and we were able to remove older data with high positional uncertainties. We generated a revised high-resolution digital elevation model (DEM to investigate the potential for an old ice record in this region, and used laser altimetry to confirm a Cryosat-2 derived DEM for inferring the glaciological state of the candidate area. By measuring the specularity content of the bed, we were able to find an additional 50 subglacial lakes near the candidate site, and by Doppler focusing the radar data, we were able to map out the roughness of the bed at length scales of hundreds of meters. We find that the primary candidate region contains elevated rough topography interspersed with scattered subglacial lakes and some regions of smoother bed. Free subglacial water appears to be restricted from bed overlain by ice thicknesses of less than 3000 m. A site near the ice divide was selected for further investigation. The high resolution of this ice thickness data set also allows us to explore the nature of ice thickness uncertainties in the context of radar geometry and processing.

  19. Performance and Analysis of Floating dome Anaerobic Digester with Wet and Dry Feedstock

    Science.gov (United States)

    Sathish, S.; Parthiban, A.; Venugopal, S.; Jothi Prakash, V. M.

    2017-03-01

    The objective of this study is to evaluate the feasibility of anaerobic digestion to generate biogas yield and it’s performed using wet and dry feed stock. The laboratory experiment is conducted in a floating dome type anaerobic digester with 1m3 capacity. It is made up of fibre material at continues process. The starter cowdung used as an inoculum of the anaerobic digester. Then raw materials feeded as a wet type wheat straw and dry type wheat straw is the ratio of 1:1 waste/water in both the experiments wet and dry wheat straw. In this experiments are fermented at 30ºC to 35ºC temperature is maintained. The daily biogas yield, cumulative biogas yield, pH, CH4, and hydro retention time these parameters is studied and analysed. The maximum daily biogas is 25liters and 42% of methane is achieved in dry wheat straw at 15th day of digestion. The highest gas yield obtained in dry condition compare to wet condition and acid level also decreased in wet digestion.

  20. A Dome-Headed Stem Archosaur Exemplifies Convergence among Dinosaurs and Their Distant Relatives.

    Science.gov (United States)

    Stocker, Michelle R; Nesbitt, Sterling J; Criswell, Katharine E; Parker, William G; Witmer, Lawrence M; Rowe, Timothy B; Ridgely, Ryan; Brown, Matthew A

    2016-10-10

    Similarities in body plan evolution, such as wings in pterosaurs, birds, and bats or limblessness in snakes and amphisbaenians, can be recognized as classical examples of convergence among animals [1-3]. We introduce a new Triassic stem archosaur that is unexpectedly and remarkably convergent with the "dome-headed" pachycephalosaur dinosaurs that lived over 100 million years later. Surprisingly, numerous additional taxa in the same assemblage (the Otis Chalk assemblage from the Dockum Group of Texas) demonstrate the early acquisition of morphological novelties that were later convergently evolved by post-Triassic dinosaurs. As one of the most successful clades of terrestrial vertebrates, dinosaurs came to occupy an extensive morphospace throughout their diversification in the Mesozoic Era [4, 5], but their distant relatives were first to evolve many of those "dinosaurian" body plans in the Triassic Period [6-8]. Our analysis of convergence between archosauromorphs from the Triassic Period and post-Triassic archosaurs demonstrates the early and extensive exploration of morphospace captured in a single Late Triassic assemblage, and we hypothesize that many of the "novel" morphotypes interpreted to occur among archosaurs later in the Mesozoic already were in place during the initial Triassic archosauromorph, largely non-dinosaurian, radiation and only later convergently evolved in diverse dinosaurian lineages. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Study of borehole plugging in bedded salt domes by earth melting technology

    Energy Technology Data Exchange (ETDEWEB)

    Black, D.L.

    1975-06-01

    The intent of this program is to define the most viable Melted In situ Rock salt Plug (MIRP) System options, these options being addressed primarily from the downhole subsystem perspective, with a conventional drill rig as the basis for the surface part of the MIRP System. Preliminary experiments had indicated that it is possible to backfill the open penetrations in the domed salt deposits with a melted in situ rocksalt plug such that in time the melted rock salt plug effectively duplicates the parent virgin salt. The programmatic assumption for the requirement of duplicating the virgin salt with a MIRP provides the basis for this study. A system functional analysis was performed to establish the requirements for the performance of the overall MIRP System. A similar functional analysis was conducted for the salt plug that would be formed by the MIRP System. Based on the analyses of the material, thermal, and structural behavior of the salt plug, the requirements for the formation of an acceptable salt plug were determined. From the functional analysis a determination was made of the operation of the hardware for the downhole portion of the MIRP System. From that perspective several design concepts were formulated. For these design concepts a technology roadmap was developed. The pertinent aspects, results, conclusions and recommendations of the above are summarized in the sections that follow.

  2. Towards the development of a salinity impact category for South ...

    African Journals Online (AJOL)

    Towards the development of a salinity impact category for South African life cycle assessments: part 3 - salinity potentials. ... Surface water 0.165. Natural surfaces 0.031. Agricultural surfaces 1.000. An additional impact category for salinity effects is therefore proposed, and the derived salinity potentials (also known as ...

  3. Effects of salinity on the survival of the Brackwater mussel ...

    African Journals Online (AJOL)

    Additionally, animals were exposed to a gradual change in salinity, using treatments that exceeded the minimum and maximum salinities mussels were previously able to tolerate. In all four experiments, animals were able to tolerate salinity levels up to 20. However, a wider salinity tolerance, up to 50, was shown by animals ...

  4. Investigation of Soil Salinity to Distinguish Boundary Line between ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: Gradual drying of Urmia Lake has left vast saline areas all around it, increasing the risk of salinization of agricultural lands next to the Lake. The current research was aimed to predict soil salinity and distinguish the boundary line between saline and agricultural lands by taking in to account the spatial variability ...

  5. Evaluating links between deformation, topography and surface temperature at volcanic domes: Results from a multi-sensor study at Volcán de Colima, Mexico

    Science.gov (United States)

    Salzer, Jacqueline T.; Milillo, Pietro; Varley, Nick; Perissin, Daniele; Pantaleo, Michele; Walter, Thomas R.

    2017-12-01

    Dome building activity is common at many volcanoes and due to the gravitational instability, a dome represents one of the most hazardous volcanic phenomena. Shallow volcanic processes as well as rheological and structural changes of the dome affecting the fluid transport have been linked to transitions in eruptive activity. Also, hydrothermal alteration may affect the structural integrity of the dome, increasing the potential for collapse. However, mapping the deformation and details of fluid escape at the summit of steep sloped volcanoes and integrating these with other types of data is challenging due to difficult access and poor coverage. Here we present for the first time the near-vertical and near-horizontal surface deformation field of a quiescent summit dome and the relationships with degassing and topographic patterns. Our results are derived from high resolution satellite radar interferometry (InSAR) time series based on a year of TerraSAR-X SpotLight acquisitions and Structure from Motion (SfM) processing of overflight infrared data at Volcán de Colima, Mexico. The identified deformation is dominated by localized heterogeneous subsidence of the summit dome exceeding rates of 15 cm/yr, and strongly decreasing over the year 2012, up to the renewal of explosive and extrusive activity in early 2013. We tentatively attribute the deformation to the degassing, cooling and contraction of the dome and shallow conduit material. We also find that the results strongly differ depending on the chosen InSAR time series method, which potentially overprints the true physical complexities of small scale, shallow deformation processes. The combined interpretation of the deformation and infrared data reveals a complex spatial relationship between the degassing pathways and the deformation. While we observe no deformation across the crater rim fumaroles, discontinuities in the deformation field are more commonly observed around the dome rim fumaroles and occasionally on the

  6. The Influence of Dome Size, Parent Vessel Angle, and Coil Packing Density on Coil Embolization Treatment in Cerebral Aneurysms

    Science.gov (United States)

    Frakes, David H.; Indahlastari, Aprinda; Ryan, Justin; Babiker, M. Haithem; Nair, Priya; Parthas, Varsha

    2013-11-01

    Intracranial aneurysms (ICAs) are dilated cerebral blood vessels. Treating ICAs effectively prior rupture is crucial since their association with 45% mortality rate. Embolic coiling is the most effective ICA treatment. Series of embolic coils are deployed into the aneurysm with the intent of reaching a sufficient packing density (PD) to help seal off the ICA from circulation. While coiling is effective, treatment failures have been associated with basilar tip aneurysms (BTAs), perhaps because of their geometry. The aim of this study was to examine the effect of dome size, parent vessel (PV) angle, and PD on intraaneurysmal (IA) velocity, crossneck (CN) flow and low wall shear stress (WSS) area using simulations and experiments in idealized BTA models. IA velocity and CN flow decreased after coiling, while low WSS area increased. With increasing PD, IA velocity and CN flow were further reduced, but low WSS area had a minimal change. Coil PD had the greatest impact on post-treatment flow while dome size had a greater impact than PV angle. Overall, the role of aneurysmal geometries may vary depending on treatment goal and timing e.g., high coil PD may reduce IA velocity more effectively during early aneurysmal growth when the dome size is small. Funded by the American Heart Association.

  7. [Ultrasound-guided microwave ablation with artificial pleural effusion for liver tumor adjacent to 
diaphragmatic dome].

    Science.gov (United States)

    Tang, Tian; Gu, Shanzhi; Li, Guowen; Huang, Manping; Huang, Bin; Xiong, Zhengping

    2017-02-28

    To explore the value of ultrasound-guided microwave ablation with artificial pleural effusion for liver tumor adjacent to diaphragmatic dome.
 Methods: A total of 34 patients with liver tumors located at diaphragmatic dome in Hunan Provincial Tumor Hospital were recruited from January 2014 to October 2015. The number of lesions ≤3 or lesion diameter ≤5 cm was in line with the microwave ablation indications. B ultrasound-guided microwave ablation for the liver tumors was undertaken after the artificial pleural effusion being established. 3-4 weeks later after the microwave ablation, all patients were imaged with enhance CT or MRI. The effect of ablation and the complications were evaluated.
 Results: There were 49 lesions in 34 patients, including 30 cases (88.2%) of complete ablation (CA), 3 cases (8.8%) of partial ablation (PA) and one case with new lesions after ablation (2.9%). Thirty-four patients had (1 580±230.7) mL of pleural effusion volume, while one case had bloody pleural effusion. One case had a diaphragmatic thermal injury, and one case had a biliary tumor infection. All of them showed remission after symptomatic treatment. 
 Conclusion: Combination of ultrasound-guided microwave ablation with artificial pleural effusion is a safe and effective therapy for liver tumor adjacent to diaphragmatic dome.

  8. Hydrological self-regulation of domed peatlands in south-east Asia and consequences for conservation and restoration

    Directory of Open Access Journals (Sweden)

    R. Dommain

    2010-10-01

    Full Text Available This article explores the hydrological constraints on the existence of forested peat domes (peat swamp forests in the humid tropics, the self-regulation mechanisms that enable them to persist and the implications for restoration of damaged domes. The most important requirement for the preservation of peat is permanent saturation by water. The variable input of precipitation must be translated into a constant water supply to the peat mound. In intact tropical peat swamp domes, water is stored above the peat surface in depressions between hummocks that surround tree trunks and between spreading buttress roots. This above-ground water store is analogous to the water stored in the loose upper layer of peat and vegetation in Sphagnum bogs. The horizontal differentiation of the peat swamp forest floor into hummocks with limited hydraulic conductivity and depressions with high storage capacity resembles the hummock-hollow patterning of these Sphagnum bogs. Hummocks and other surface elements functionally resemble V-notch weirs that regulate water availability. Buttressed trees play a key role in providing the structural elements for hydrological self-regulation. An additional level of regulation is found in the concentric zonation of forest types with increased presence of buttressed trees on steeper margins. Conservation and restoration efforts should take into account the inter-relationships between trees, water and peat and the hydrological feedbacks that operate as a consequence.

  9. The Millennium Dome "Watercycle" experiment: to evaluate water efficiency and customer perception at a recycling scheme for 6 million visitors.

    Science.gov (United States)

    Hills, S; Birks, R; McKenzie, B

    2002-01-01

    Thames Water's "Watercycle" project at the Millennium Dome was one of the largest in-building recycling schemes in Europe, designed to supply up to 500 m3/d of reclaimed water for WC and urinal flushing. It catered for over 6 million visitors in the year 2000. Overall, 55% of the water demand at the Dome was met by reclaimed water. The site was also one of the most comprehensive studies ever carried out of water conservation in a public environment, evaluating a range of water efficient appliances and researching visitor perceptions of reclaimed water. Within the Dome there were six identical core buildings housing the washrooms, which were equipped with a variety of different water-efficient devices for comparison. Water usage by the different appliances was monitored using a sophisticated metering and telemetry system. The importance of correct installation and maintenance of "high tech" water efficient devices was highlighted during the research programme, as some water wastage occurred due to poor installation. The results prove that metering should complement any large-scale water efficient system, so that any faults with the appliances can be quickly identified. The visitor survey showed very positive attitudes to the use of reclaimed water for non-potable uses.

  10. Distribution coefficient data and preliminary estimates of movement of radionuclides, Tatum salt dome, Lamar County, Mississippi. Technical letter: Dribble 31

    Energy Technology Data Exchange (ETDEWEB)

    Beetem, W.A.; Janzer, V.J.

    1963-04-10

    Estimates are made relating radionuclide movement to ground water velocity as part of the safety program for a proposed experiment to detonate nuclear devices within the Tatum salt dome. The estimates are based on distribution coefficients obtained from laboratory studies. Core samples obtained from hydrologic test well HT-3, Tatum salt dome, Lamar County, Mississippi, were equilibrated with radionuclides in solutions simulating aquifer waters found in the area. The combinations of Cenozoic sand and silty clay, and quality of water of the area were studied and summarized. The distribution coefficients obtained for different radionuclides were tested and indicate retardation factors from 1.3 to 857 for the travel time of these radionuclides when compared to the travel time of water in the aquifer system. Laboratory results indicate that migration of any radioisotope inadvertently introduced to the aquifers in the vicinity of the dome as a result of proposed nuclear test explosions would be extremely slow. Revised estimates of the rate of dissolved radioisotope movement will be made on the basis of further laboratory studies utilizing chromatographic adsorption columns of 0.5 to 4.0 feet in length.

  11. High-precision dating of volcanic events (A.D. 1301-1995) using ice cores from Law Dome, Antarctica

    Science.gov (United States)

    Palmer, Anne S.; van Ommen, Tas D.; Curran, Mark A. J.; Morgan, Vin; Souney, Joe M.; Mayewski, Paul A.

    2001-11-01

    A record of volcanic activity over the period A.D. 1301-1995 has been extracted from three Law Dome ice cores (East Antarctica). The record dating is unambiguous at the annual level from A.D. 1807 to 1995 and has an uncertainty of ±1 year at A.D. 1301. Signals from 20 eruptions are preserved in the record, including those of two unknown eruptions with acid deposition beginning in A.D. 1810.8 and A.D. 1685.8. The beginning of the ice core signal from the A.D. 1815 Tambora eruption is observed in the austral summer of A.D. 1816/1817. The mean observed stratospheric transport and deposition time to Law Dome from the eruption site is 1.5 years (σ = 0.6 years) from 11 well-dated eruptions. The largest eruption observed in the Law Dome record has its maximum in A.D. 1460 with volcanic sulfate deposition beginning in the austral winter of A.D. 1459. This event is also observed in other ice core records and is attributed to the volcano Kuwae, with an eruption date in the range A.D. 1455.9-1459.9 if all sources of error are considered. This is at least three years later than the date previously ascribed by dendrochronological and historical studies.

  12. Paleotopography and erosion rates in the central Hangay Dome, Mongolia: Landscape evolution since the mid-Miocene

    Science.gov (United States)

    Smith, Stephen G.; Wegmann, Karl W.; Ancuta, Leonard D.; Gosse, John C.; Hopkins, Chelsea E.

    2016-08-01

    Standing over 2 km above the surrounding topography and flanked by orogen-scale strike-slip faults, the Hangay Dome in central Mongolia is characterized by long wavelength high topography, basaltic eruptions spanning 30 million years, and an abundance of flat-topped summit plateaus. However, despite decades of research, the origin and timing of the intraplate Hangay Dome uplift continues to be debated. Using Landsat imagery, GIS, and cosmogenic beryllium-10, we employ geomorphic investigations of (1) paleotopography preserved beneath basalt flows of known age, (2) erosion rates at various temporal scales, and (3) the relative contribution of glacial activity to total erosion to provide insight into the nature of landscape evolution in the Egiin Davaa region of the central Hangay Dome since the middle Miocene. Reconstruction of paleo-valleys cut into Paleozoic basement rock that exhibit a degree of local relief (>600 m) similar to the modern landscape, sluggish mean erosion rates (climate oscillations beginning in the Pliocene have led to an environment influenced primarily by the activity of glaciers. These results provide support for uplift onset during the Oligocene or early Miocene, quantify landscape evolution since the middle Miocene, and underscore the importance of considering geomorphic archives found on Earth's surface when building models of intra-continental epeirogeny.

  13. Dome collapse mechanisms and block-and-ash flow emplacement dynamics inferred from deposit and impact mark analysis, Mono Craters, CA

    OpenAIRE

    Dennen, R. L.; Bursik, M. I.; Roche, Olivier

    2014-01-01

    Characteristics of the Panum block-and-ash flow (BAF) deposit, Mono Craters, CA, were analyzed to determine the mechanisms of collapse of the parent dome and dynamics of emplacement of the BAF. Granulometry, componentry, and obsidian water content data were used to define distinct facies of the Panum BAF deposit. These suggest a sequential, three-stage collapse model for the ancestral dome of the Panum vent, with destabilization first of its cold, brittle outer margins and then of its hot, du...

  14. Large Spun Formed Friction-Stir Welded Tank Domes for Liquid Propellant Tanks Made from AA2195: A Technology Demonstration for the Next Generation of Heavy Lift Launchers

    Science.gov (United States)

    Stachulla, M.; Pernpeinter, R.; Brewster J.; Curreri, P.; Hoffman, E.

    2010-01-01

    Improving structural efficiency while reducing manufacturing costs are key objectives when making future heavy-lift launchers more performing and cost efficient. The main enabling technologies are the application of advanced high performance materials as well as cost effective manufacture processes. This paper presents the status and main results of a joint industrial research & development effort to demonstrate TRL 6 of a novel manufacturing process for large liquid propellant tanks for launcher applications. Using high strength aluminium-lithium alloy combined with the spin forming manufacturing technique, this development aims at thinner wall thickness and weight savings up to 25% as well as a significant reduction in manufacturing effort. In this program, the concave spin forming process is used to manufacture tank domes from a single flat plate. Applied to aluminium alloy, this process allows reaching the highest possible material strength status T8, eliminating numerous welding steps which are typically necessary to assemble tank domes from 3D-curved panels. To minimize raw material costs for large diameter tank domes for launchers, the dome blank has been composed from standard plates welded together prior to spin forming by friction stir welding. After welding, the dome blank is contoured in order to meet the required wall thickness distribution. For achieving a material state of T8, also in the welding seams, the applied spin forming process allows the required cold stretching of the 3D-curved dome, with a subsequent ageing in a furnace. This combined manufacturing process has been demonstrated up to TRL 6 for tank domes with a 5.4 m diameter. In this paper, the manufacturing process as well as test results are presented. Plans are shown how this process could be applied to future heavy-lift launch vehicles developments, also for larger dome diameters.

  15. Dwarf cashew growth irrigated with saline waters

    Directory of Open Access Journals (Sweden)

    Hugo Orlando Carvallo Guerra

    2009-12-01

    Full Text Available The cashew production is one of the most important agricultural activities from the social-economical viewpoint for the North East of Brazil; besides to produce a great deal of hand labor, it is very important as an exporting commodity. The inadequate use of irrigation in the semi arid regions of the North East of Brazil has induced soil salinization and consequently problems for the irrigated agriculture. In spite of this, few works have been conducted to study the effect of saline stress on the growth and development of the cashew. Because of the lack of information for this crop, an experiment was conducted to study the effect of salinity stress on the phytomass production and nutrient accumulation on the different organs of the precocious dwarf cashew (Anacardium occidentale L. clone CCP76. The study was conducted under controlled conditions using as statistical scheme a randomized block design factorial with six replicates. Five salinity treatments were considered for the irrigation water (electrical conductivities of 0.8, 1.6, 2.4, 3.2 and 4.0 dS m-1 at 25oC. The increasing in salinity of the irrigation water reduced the phytomass at different organs of the studied plant. The nitrogen, phosphorus, potassium, chloride and sodium in the plant varied with the salinity of the irrigation water according with the part of the plant analyzed; in some parts increased, in others decreased, in others increased initially and decreased afterwards, and finally, in other part of the plant the salinity of the irrigation water did not affect the nutrient concentration.

  16. Statistical analysis of the sustained lava dome emplacement and destruction processes at Popocatépetl volcano, Central México

    Science.gov (United States)

    Mendoza-Rosas, Ana Teresa; Gómez-Vázquez, Ángel; De la Cruz-Reyna, Servando

    2017-06-01

    Popocatépetl volcano reawakened in 1994 after nearly 70 years of quiescence. Between 1996 and 2015, a succession of at least 38 lava domes have been irregularly emplaced and destroyed, with each dome reaching particular volumes at specific emplacement rates. The complexity of this sequence is analyzed using statistical methods in an attempt to gain insight into the physics and dynamics of the lava dome emplacement and destruction process and to objectively assess the hazards related to that volcano. The time series of emplacements, dome residences, lava effusion lulls, and emplaced dome volumes and thicknesses are modeled using the simple exponential and Weibull distributions, the compound non-homogeneous generalized Pareto-Poisson process (NHPPP), and the mixture of exponentials distribution (MOED). The statistical analysis reveals that the sequence of dome emplacements is a non-stationary, self-regulating process most likely controlled by the balance between buoyancy-driven magma ascent and volatile exsolution crystallization. This balance has supported the sustained effusive activity for decades and may persist for an undetermined amount of time. However, the eruptive history of Popocatépetl includes major Plinian phases that may have resulted from a breach in that balance. Certain criteria to recognize such breaching conditions are inferred from this statistical analysis.

  17. Genetic diversity analysis of salinity related germplasm in cotton

    OpenAIRE

    Lina Zhang; Wuwei Ye; Junjuan Wang; Baoxiang Fan; Delong Wang

    2010-01-01

    In order to study the genetic variation of salinity related cotton germplasm, 47 upland cotton accessions including 23 salinity tolerant materials and 24 salinity sensitive materials were explored using 88 simple sequence repeat (SSR) markers. We detected a total of 338 alleles at 88 SSR loci with an average of 3.841 alleles per locus, 333 of these alleles were detected in salinity tolerant germplasm and 312 alleles in salinity sensitive germplasm. Mean polymorphism information content (PIC),...

  18. Options for salinity mitigation in the Murray-Darling Basin

    OpenAIRE

    Schrobback, Peggy; Adamson, David; Quiggin, John

    2008-01-01

    The Murray-Darling Basin faces increasing pressure on water quantity and quality. In 2006-07, salt interception schemes implemented as part of the Murray–Darling Basin Salinity Management strategy removed over 470,000 tonnes of salt from the water supply, reducing the salinity of water flowing to Adelaide by about 200 EC units. However, the costs of salinity mitigation schemes are increasing. With possible continuing declines in average inflows, costs of salinity and salinity mitigation are...

  19. Catalog of Mount St. Helens 2004-2007 Dome Samples with Major- and Trace-Element Chemistry

    Science.gov (United States)

    Thornber, Carl R.; Pallister, John S.; Rowe, Michael C.; McConnell, Siobhan; Herriott, Trystan M.; Eckberg, Alison; Stokes, Winston C.; Cornelius, Diane Johnson; Conrey, Richard M.; Hannah, Tammy; Taggart, Joseph E.; Adams, Monique; Lamothe, Paul J.; Budahn, James R.; Knaack, Charles M.

    2008-01-01

    Sampling and analysis of eruptive products at Mount St. Helens is an integral part of volcano monitoring efforts conducted by the U.S. Geological Survey?s Cascades Volcano Observatory (CVO). The objective of our eruption sampling program is to enable petrological assessments of pre-eruptive magmatic conditions, critical for ascertaining mechanisms for eruption triggering and forecasting potential changes in eruption behavior. This report provides a catalog of near-vent lithic debris and new dome-lava collected during 34 intra-crater sampling forays throughout the October 2004 to October 2007 (2004?7) eruptive interval at Mount St. Helens. In addition, we present comprehensive bulk-rock geochemistry for a time-series of representative (2004?7) eruption products. This data, along with that in a companion report on Mount St. Helens 2004 to 2006 tephra by Rowe and others (2008), are presented in support of the contents of the U.S. Geological Survey Professional Paper 1750 (Sherrod and others, eds., 2008). Readers are referred to appropriate chapters in USGS Professional Paper 1750 for detailed narratives of eruptive activity during this time period and for interpretations of sample characteristics and geochemical data. The suite of rock samples related to the 2004?7 eruption of Mount St. Helens and presented in this catalog are archived at the David A. Johnson Cascades Volcano Observatory, Vancouver, Wash. The Mount St. Helens 2004?7 Dome Sample Catalogue with major- and trace-element geochemistry is tabulated in 3 worksheets of the accompanying Microsoft Excel file, of2008-1130.xls. Table 1 provides location and sampling information. Table 2 presents sample descriptions. In table 3, bulk-rock major and trace-element geochemistry is listed for 44 eruption-related samples with intra-laboratory replicate analyses of 19 dacite lava samples. A brief overview of the collection methods and lithology of dome samples is given below as an aid to deciphering the dome sample

  20. Genesis of diamond dust, ice fog and thick cloud episodes observed and modelled above Dome C, Antarctica

    Science.gov (United States)

    Ricaud, Philippe; Bazile, Eric; del Guasta, Massimo; Lanconelli, Christian; Grigioni, Paolo; Mahjoub, Achraf

    2017-04-01

    Episodes of thick cloud and diamond dust/ice fog were observed during 15 March to 8 April 2011 and 4 to 5 March 2013 in the atmosphere above Dome C (Concordia station, Antarctica; 75°06' S, 123°21' E; 3233 m a.m.s.l.). The objectives of the paper are mainly to investigate the processes that cause these episodes based on observations and to verify whether operational models can evaluate them. The measurements were obtained from the following instruments: (1) a ground-based microwave radiometer (HAMSTRAD, H2O Antarctica Microwave Stratospheric and Tropospheric Radiometers) installed at Dome C that provided vertical profiles of tropospheric temperature and absolute humidity every 7 min; (2) daily radiosoundings launched at 12:00 UTC at Dome C; (3) a tropospheric aerosol lidar that provides aerosol depolarization ratio along the vertical at Dome C; (4) down- and upward short- and long-wave radiations as provided by the Baseline Surface Radiation Network (BSRN) facilities; (5) an ICE-CAMERA to detect at an hourly rate the size of the ice crystal grains deposited at the surface of the camera; and (6) space-borne aerosol depolarization ratio from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) lidar aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) platform along orbits close to the Dome C station. The time evolution of the atmosphere has also been evaluated by considering the outputs from the mesoscale AROME and the global-scale ARPEGE meteorological models. Thick clouds are detected during the warm and wet periods (24-26 March 2011 and 4 March 2013) with high depolarization ratios (greater than 30 %) from the surface to 5-7 km above the ground associated with precipitation of ice particles and the presence of a supercooled liquid water (depolarization less than 10 %) clouds. Diamond dust and/or ice fog are detected during the cold and dry periods (5 April 2011 and 5 March 2013) with high depolarization ratios (greater

  1. Ductile Flow Accompanied by Vertical Thinning and Near-Isothermal Decompression in the Lhagoi Kangri Gneiss Dome, Southern Tibet

    Science.gov (United States)

    Diedesch, T.; Jessup, M. J.; Cottle, J. M.; Zeng, L.

    2016-12-01

    The North Himalayan antiform marks the location of a series of gneiss-cored domes along the southern Tibetan Plateau that record a history of Eocene to Oligocene crustal thickening and ductile flow followed by Miocene exhumation as the locus of India-Asia convergence was transferred southward. Key features common to these North Himalayan gneiss domes (NHGD) include: (1) a core of Precambrian to Cambrian granitic gneiss (+/- Miocene granite/granitic gneiss), (2) a carapace of Paleozoic to Mesozoic metasedimentary rocks that record Barrovian metamorphism, (3) fabrics that record crustal thickening (D1) and ductile shear with a component of vertical thinning (D2), and (4) an Oligocene to Miocene period of crustal melting and leucogranite emplacement. Our structural, petrologic, and geochronologic data from the Lhagoi Kangri dome (LKD) provide new constraints on the NHGD evolution and the early development of Himalayan middle crust. The LKD is a 25 x 40 km elliptical dome located 100 km NNW of Mt. Everest. Lhagoi Kangri is cored by orthogneiss nonconformably overlain by Paleozoic to Triassic mixed siliciclastic and carbonate metasedimentary rocks. At the highest structural levels deformation is characterized by km-scale N- and S-vergent folds and slaty cleavage (collectively, D1). A later generation of ductile deformation (D2) resulted in tightening of F1 folds and transposition of S1 cleavage at intermediate structural levels, while at deeper structural positions, D2 resulted in the formation of mylonitic foliation characterized by a pervasive LS fabric as well as C and C' shear bands filled by biotite, muscovite, and/or silliamanite laths. Pelitic intervals within the metasedimentary strata record concentric chlorite to sillimanite Barrovian metamorphic isograds (M1), and garnet- to sillimanite-zone rocks record high-temperature, nearly isothermal decompression (M2). Electron probe microanalysis and in-situ laser ablation split stream petrochronology of monazite from

  2. Hypertonic 3% Saline in Comparison with 0.9% (Normal Saline in Treatment of Acute Bronchiolitis

    Directory of Open Access Journals (Sweden)

    Abdul-karem Jasem Mohammed Al-bahadily

    2017-01-01

    Full Text Available BackgroundBronchiolitis is the commonest cause of lower respiratory tract infection in infant. Respiratory syncytial virus is the commonest cause of bronchiolitis. This study aimed to assess the efficacy of nebulized 3% hypertonic saline and salbutamol in the treatment of acute bronchiolitis in comparison with nebulized 0.9% saline and salbutamol.Materials and MethodsA prospective case second multicenter study was done at two pediatric tertiary centers at the period from 1st of December 2014 to 31 of March 2015. A total of 100 previously well infant and children of age 1-24 months with clinical diagnoses of bronchiolitis who were admitted to the hospital were included. They were divided into two groups, the study group received 4 ml of nebulized hypertonic 3% saline (for 14 days, and second group received 4 ml of nebulized normal 0.9% saline (for 14 days, each co-administer with 0.5 ml salbutamol.ResultsAll patients with acute bronchiolitis having similar baseline characteristic, mean age 4.9 + Standard deviation (SD months, male gender constitutes 68% of the patients and the majority (67% of the cases were below 6 months. The mean of clinical severity score at admission was 6.4 for normal saline (NS group and 6.6 for hypertonic 3% saline (HS group. The mean length of hospital stay of normal saline group = 4.3 + Standard deviation (SD day and for hypertonic saline group was = 4.7 + Standard deviation (SD day.ConclusionWe didn’t find any advantage of hypertonic 3% saline over 0.9% normal saline in terms of length of hospital stay and clinical severity score.

  3. Mud Volcanoes - Analogs to Martian Cones and Domes (by the Thousands!)

    Science.gov (United States)

    Allen, Carlton C.; Oehler, Dorothy

    2010-01-01

    Mud volcanoes are mounds formed by low temperature slurries of gas, liquid, sediments and rock that erupt to the surface from depths of meters to kilometers. They are common on Earth, with estimates of thousands onshore and tens of thousands offshore. Mud volcanoes occur in basins with rapidly-deposited accumulations of fine-grained sediments. Such settings are ideal for concentration and preservation of organic materials, and mud volcanoes typically occur in sedimentary basins that are rich in organic biosignatures. Domes and cones, cited as possible mud volcanoes by previous authors, are common on the northern plains of Mars. Our analysis of selected regions in southern Acidalia Planitia has revealed over 18,000 such features, and we estimate that more than 40,000 occur across the area. These domes and cones strongly resemble terrestrial mud volcanoes in size, shape, morphology, associated flow structures and geologic setting. Geologic and mineralogic arguments rule out alternative formation mechanisms involving lava, ice and impacts. We are studying terrestrial mud volcanoes from onshore and submarine locations. The largest concentration of onshore features is in Azerbaijan, near the western edge of the Caspian Sea. These features are typically hundreds of meters to several kilometers in diameter, and tens to hundreds of meters in height. Satellite images show spatial densities of 20 to 40 eruptive centers per 1000 square km. Many of the features remain active, and fresh mud flows as long as several kilometers are common. A large field of submarine mud volcanoes is located in the Gulf of Cadiz, off the Atlantic coasts of Morocco and Spain. High-resolution sonar bathymetry reveals numerous km-scale mud volcanoes, hundreds of meters in height. Seismic profiles demonstrate that the mud erupts from depths of several hundred meters. These submarine mud volcanoes are the closest morphologic analogs yet found to the features in Acidalia Planitia. We are also conducting

  4. Hydrocarbons in the Hauptsalz formation of the Gorleben salt dome. Content, distribution and origin

    Energy Technology Data Exchange (ETDEWEB)

    Pusch, Maximilian; Hammer, Joerg; Ostertag-Henning, Christian [Federal Institute for Geosciences and Natural Resources (BGR), Hannover (Germany)

    2015-07-01

    In the frame of the geological exploration of the Gorleben salt dome (November 2010 to November 2012) concentrations and compositions of hydrocarbons occuring in the main rock salt (Hauptsalz, Stassfurt series, z2) have been investigated. These exploration works followed former investigations of Gerling et al. (2002) and Bornemann et al. (2008). In order to get fresh, unaltered and representative samples beyond the EDZ (excavation damaged zone) for mineralogical and geochemical analyses, about 45 boreholes have been drilled at the 840 m level of the Gorleben exploration mine. These boreholes have been arranged in equal distances (depending on the mine structure) alongside crosscut 1 west (each 6 m long) and crosscut 1 east (each 9 m long). In addition 20 packer boreholes (10 packer boreholes per crosscut) for pressure build-up recording and hydrocarbon sampling have also been established. Immediately after drilling, core samples from the Hauptsalz for organic geochemical analyses have been retrieved and were dissolved in deionised and degased water. The results of analyses of about 210 samples scattered over all 45 boreholes reveal a total background concentration of hydrocarbons (C{sub 1} to C{sub 40}) of 0,24 mg/kg. 70 samples have concentrations between 1 mg/kg and 50 mg/kg (average 2,66 mg/kg) with 5 outliers up to 442 mg/kg in crosscut 1 west (Hammer et al. 2012, 2013). The drill cores have been investigated and documented by using ultraviolet light (l = 254 nm) in respect of visible indications of the existence of fluorescing aromatic hydrocarbons. Analyses revealed a high level of heterogeneous hydrocarbon distribution in the shape of isolated, irregular streaks, clusters, clouds and occasionally layers mainly located in recrystallized zones of the Hauptsalz. Thin sections and thick sections showed that hydrocarbons in z2HS1 (Knaeuelsalz) and z2HS2 (Streifensalz) samples are either located as black to brownish dendritical fluid inclusions alongside the grain

  5. Long-term record of atmospheric and snow surface nitrate from Dome C (Central Antarctica)

    Science.gov (United States)

    Traversi, Rita; Becagli, Silvia; Brogioni, Marco; Caiazzo, Laura; Ciardini, Virginia; Giardi, Fabio; Legrand, Michel; Macelloni, Giovanni; Petkov, Boyan; Preunkert, Suzanne; Scarchilli, Claudio; Severi, Mirko; Vitale, Vito; Udisti, Roberto

    2017-04-01

    Nitrate is the end product of the oxidation of atmospheric nitrogen oxides and one of the most abundant ions present in polar ice and snow, mainly as nitric acid in present-climate conditions. Nitrate stratigraphies from snow and ice layers have the potential to provide records of past changes in atmospheric composition, including atmospheric NOx cycling and oxidative capacity, as well as past solar activity or major variations in Earth's magnetic field. Nevertheless, in order to exploit such a potential, chemical concentrations in the air, snow, firn and ice core need to be correlated. Hence, the knowledge of the link between atmosphere and snow composition at the time of deposition is basic to reconstruct past climate and past atmospheric chemical composition. The extent of such knowledge depends on whether the species of interest are gaseous or in the condensed phase, and if they are reversible and/or irreversibly deposited to snow. In order to provide a contribution to their air-to-snow exchange in the Antarctic plateau, as well as to the understanding of dominant sources and sinks of nitrate, we present here nitrate records in atmospheric aerosol and surface snow sampled at high resolution, all year-round, at Dome C along 9 years (November 2004 - November 2013). This represents the longest and most highly resolved record from continental Antarctica, where continuous and long-term atmosphere and snow samplings are particularly difficult due to the extreme meteorological conditions and, at the same time, need of extra-care in avoiding contamination due to the low level of ion concentrations. Results confirm, on a larger statistical data set with respect to previous observations, nitrate seasonal pattern with summer maxima both for aerosol and surface snow, in-phase with UV solar irradiance. Such a temporal pattern is likely a combination of nitrate sources and post-depositional processes that enhance during summer. Moreover, a case study of synoptic analysis for

  6. Hypertonic saline for bronchiolitis in infants.

    Science.gov (United States)

    Grewal, Simran; Goldman, Ran D

    2015-06-01

    Recently, a 1-year-old patient returned from admission in the hospital for bronchiolitis, and the report I received indicated that he was treated with inhaled hypertonic saline, among other treatments. Is this therapy recommended for children in the acute care setting? Bronchiolitis, caused mostly by respiratory syncytial virus, is very common in the winter. It is the most frequent cause of hospitalization in infancy. Several good studies have been conducted in the past decade on the use of nebulized hypertonic saline for bronchiolitis management; however, they offer conflicting results. While there might be a role for the use of nebulized hypertonic saline in children who are hospitalized with bronchiolitis for more than 3 days, treatment in other settings does not confer enough benefit to recommend its use. Copyright© the College of Family Physicians of Canada.

  7. [Percutaneous radiofrequency ablation therapy with left single lung ventilation for liver carcinoma in the hepatic dome].

    Science.gov (United States)

    Sun, Wen-bing; Wang, Zhen-yuan; Zhang, Yan-feng; Ding, Xue-mei; Wang, Bao-qiang

    2007-09-01

    To evaluate the advantages of percutaneous radiofrequency ablation (PRFA) therapy with contralateral single lung ventilation (SLV) for liver carcinoma in the hepatic dome (LCHD). The clinical data of 10 patients (the SLV group) with LCHD consecutively treated from January to December 2006 were retrospectively analyzed. And another 10 cases (the control group) with LCHD treated from January 2004 to December 2005 were selected with a strict inclusion criterion for compared test according to rules of same diagnosis, similar tumor bulk and site, same sex, similar age and liver function. The patients' ages and tumor diameters of the 2 groups were compared with t-test and the rates of complications and incomplete tumor ablation were compared with chi2-test. There was no statistical difference in ages and tumor diameters between the 2 groups (P > 0.05). The average number of radiofrequency ablation needle punctures in the SLV group was significantly less than the control group (3.4 +/- 0.4 vs. 6.1 +/- 0.8, P pleural effusion (n = 1). There was no mortality in the 2 groups. Though the rate of incomplete tumor necrosis in the SLV group was not statistically lower than that in the control group (10% vs. 40%), the occurrence rate of the undesirable event (complication and incomplete tumor necrosis) of the SLV group was significantly lower than that of the control group (10% vs. 60%, P < 0.05). The durations and costs of operating procedure were not significantly different between the 2 groups. Left SLV makes PRFA for LCHD more efficient, effective and safe.

  8. Anisoplanatic error evaluation and wide-field adaptive optics performance at Dome C, Antarctica

    Science.gov (United States)

    Carbillet, M.; Aristidi, É.; Giordano, C.; Vernin, J.

    2017-11-01

    The aim of this paper is twofold: (i) to deduce the most representative C_N^2 profile(s) for Dome C (DC), Antarctica, from the latest measurements, and (ii) to evaluate the performance of a wide-field adaptive optics (AO) system equipping a 2-3 m telescope. Two models of the C_N^2 profile, corresponding to the bimodal distribution of seeing (a poor seeing mode and a good seeing mode), are composed from both Single Star Scidar data and balloon radio soundings. The anisoplanatic error is first evaluated for a standard AO system from Monte Carlo simulations. DC is shown to outperform Mauna Kea for both seeing modes. A simple ground-layer AO (GLAO) system is then considered. This provides an anisoplanatic error of less than 150 nm over a field of 30 arcmin for the good seeing mode, corresponding to a basic performance Strehl ratio (considering also the fitting and the servo-lag errors) of more than ˜80 per cent in K and ˜50 per cent in J. The poor seeing model shows performance comparable to the Mauna Kea model. We also studied the influence of telescope elevation, showing that a telescope at 40 m would perform, in the poor seeing mode, like a telescope observing 8 m above the ground in the good seeing mode. Finally, we show that while tip-tilt-only correction permits high levels of correction in the good seeing mode at 40 m, it is not as efficient as the GLAO system, even at an altitude of 8 m, and it is not sufficient for high levels of correction for poor seeing, even at a height of 40 m.

  9. Macular Bruch's membrane defect and dome-shaped macula in high myopia.

    Science.gov (United States)

    Fang, Yuxin; Jonas, Jost B; Yokoi, Tae; Cao, Kejia; Shinohara, Kosei; Ohno-Matsui, Kyoko

    2017-01-01

    To examine an association between macular Bruch's membrane defects (MBMD) and a dome-shaped appearance of the macula (DSM). Retrospective, observational case series study. The study included highly myopic individuals who were consecutively examined between May 2014 and December 2015. The patients underwent swept-source optical coherence tomography (OCT) for visualization of DSM and MBMDs defined as Bruch´s membrane defects located at a distance of maximal 1500 μm from the foveola. Out of 1983 highly myopic eyes (1057 patients), 166 eyes (8.4%; 95% confidence interval (CI):7.2%,9.6%)) showed a DSM and 534 eyes showed a MBMD. In multivariate binary regression analysis, higher prevalence of DSM was associated with a higher prevalence of a MBMD (P<0.001; OR: 1.96; 95%CI: 1.40, 2.75) after adjusting for longer axial length (P<0.001; odds ratio (OR): 1.27; 95%CI: 1.16, 1.38). In eyes with a DSM partially surrounded by a MBMD, the retina, retinal pigment epithelium (RPE) and choroid appeared relatively unchanged in the central region with Bruch´s membrane (BM) preserved. In the ring-like BM-free region surrounding the central prominent island of the DSM, the RPE, the outer and middle retinal layers, the choriocapillaris and the middle-sized choroidal vessel layer were absent. In association with a DSM, three MBMD types were differentiated: MBMDs in patchy chorioretinal atrophy, MBMDs in choroidal neovascularization-related macular atrophy, and MBMDs as temporally extending large parapapillary gamma zone. Presence of a DSM was significantly associated with the presence of MBMDs. The morphology of the DSM in association with MBMDs may be associated with a focal relaxation of the posterior sclera, no longer pushed outward by an expanding BM but allowed to partially bulge inward, leading to the formation of a DSM.

  10. Wave Induced Saline Intrusion in Sea Outfalls

    DEFF Research Database (Denmark)

    Larsen, Torben; Burrows, Richard

    1989-01-01

    Experimental and numerical studies have shown that the influence of wave increases the tendency of saline intrusion in multi-riser sea outfalls. The flow field in the diffusor under such unsteady and inhomogeneous circumstances is in general very complex, but when sufficient wave energy is dissip......Experimental and numerical studies have shown that the influence of wave increases the tendency of saline intrusion in multi-riser sea outfalls. The flow field in the diffusor under such unsteady and inhomogeneous circumstances is in general very complex, but when sufficient wave energy...

  11. Soil Salinity: Effect on Vegetable Crop Growth. Management Practices to Prevent and Mitigate Soil Salinization

    Directory of Open Access Journals (Sweden)

    Rui Manuel Almeida Machado

    2017-05-01

    Full Text Available Salinity is a major problem affecting crop production all over the world: 20% of cultivated land in the world, and 33% of irrigated land, are salt-affected and degraded. This process can be accentuated by climate change, excessive use of groundwater (mainly if close to the sea, increasing use of low-quality water in irrigation, and massive introduction of irrigation associated with intensive farming. Excessive soil salinity reduces the productivity of many agricultural crops, including most vegetables, which are particularly sensitive throughout the ontogeny of the plant. The salinity threshold (ECt of the majority of vegetable crops is low (ranging from 1 to 2.5 dS m−1 in saturated soil extracts and vegetable salt tolerance decreases when saline water is used for irrigation. The objective of this review is to discuss the effects of salinity on vegetable growth and how management practices (irrigation, drainage, and fertilization can prevent soil and water salinization and mitigate the adverse effects of salinity.

  12. Synthesis and electrochemical characterization of palladium-based cathode catalysts, resistant to the presence of methanol; Sintesis y caracterizacion electroquimica de catalizadores catodicos base paladio, resistentes a la presencia de metanol

    Energy Technology Data Exchange (ETDEWEB)

    Salvador, Jose J. [Centro de Investigacion y de Estudios Avanzados del IPN, Mexico D.F. (Mexico)] e-mail: jsalvador@cinvestav.mx; Collins, Virginia H. [Centro de Investigacion en Materiales Avanzados, Chihuahua, Chihuahua (Mexico); Solorza Feria, Omar [Centro de Investigacion y de Estudios Avanzados del IPN, Mexico D.F. (Mexico)

    2009-09-15

    This work presents the synthesis and characterization of palladium-based electrocatalysts (PdSn and PdPtSn) prepared with the salt-reduction method for oxygen reduction reaction (ORR). The compounds obtained are characterized by sweep electron microscopy, electron transmission microscopy and x-ray diffraction of powder. The electrocatalysts obtained had particle sizes less than 10 nm. The evaluation of the catalytic activity of the catalysts was performed using cyclic voltametry and rotating disc electrode. These experiments were conducted in an H{sub 2}SO{sub 4} 0.5 M solution with different methanol concentrations. The presence of methanol improved the catalytic activity of PdSn, but did not show any effect on the PdPtSn alloy. The performance of the DMFC mono cell using PdPtSn as a cathode showed a potential of 10 mW cm{sup -2} at 50 degrees Celsius. [Spanish] En este trabajo se presenta la sintesis y caracterizacion de electrocatalizadores de base Paladio (PdSn y PdPtSn) preparados mediante el metodo de reduccion de sales, para la reaccion de reduccion de oxigeno (RRO). Los compuestos obtenidos se caracterizaron por microscopia electronica de barrido, microscopia electronica de transmision y difraccion de rayos X de polvos. Los electrocatalizadores obtenidos presentaron un tamano de particula menores a 10 nm. La evaluacion de la actividad catalitica de los catalizadores se llevo a cabo mediante voltametria Ciclica y electrodo de disco rotatorio, estos experimentos fueron realizados en una solucion de H{sub 2}SO{sub 4} 0.5 M con diferentes concentraciones de metanol. La presencia de metanol mejoro la actividad catalitica de PdSn, pero no mostro ningun efecto sobre la aleacion PdPtSn. El desempeno de la monocelda de DMFC usando como catodo PdPtSn, mostro una potencia de 10 mW cm{sup -2} a 50 grados centigrados.

  13. Cuticle hydrocarbons in saline aquatic beetles

    Directory of Open Access Journals (Sweden)

    María Botella-Cruz

    2017-07-01

    Full Text Available Hydrocarbons are the principal component of insect cuticle and play an important role in maintaining water balance. Cuticular impermeability could be an adaptative response to salinity and desiccation in aquatic insects; however, cuticular hydrocarbons have been poorly explored in this group and there are no previous data on saline species. We characterized cuticular hydrocarbons of adults and larvae of two saline aquatic beetles, namely Nebrioporus baeticus (Dytiscidae and Enochrus jesusarribasi (Hydrophilidae, using a gas chromatograph coupled to a mass spectrometer. The CHC profile of adults of both species, characterized by a high abundance of branched alkanes and low of unsaturated alkenes, seems to be more similar to that of some terrestrial beetles (e.g., desert Tenebrionidae compared with other aquatic Coleoptera (freshwater Dytiscidae. Adults of E. jesusarribasi had longer chain compounds than N. baeticus, in agreement with their higher resistance to salinity and desiccation. The more permeable cuticle of larvae was characterized by a lower diversity in compounds, shorter carbon chain length and a higher proportion of unsaturated hydrocarbons compared with that of the adults. These results suggest that osmotic stress on aquatic insects could exert a selection pressure on CHC profile similar to aridity in terrestrial species.

  14. Salinity Tolerance Turfgrass: History and Prospects

    Directory of Open Access Journals (Sweden)

    Md. Kamal Uddin

    2013-01-01

    Full Text Available Land and water resources are becoming scarce and are insufficient to sustain the burgeoning population. Salinity is one of the most important abiotic stresses affecting agricultural productions across the world. Cultivation of salt-tolerant turfgrass species may be promising option under such conditions where poor quality water can also be used for these crops. Coastal lands in developing countries can be used to grow such crops, and seawater can be used for irrigation of purposes. These plants can be grown using land and water unsuitable for conventional crops and can provide food, fuel, fodder, fibber, resin, essential oils, and pharmaceutical products and can be used for landscape reintegration. There are a number of potential turfgrass species that may be appropriate at various salinity levels of seawater. The goal of this review is to create greater awareness of salt-tolerant turfgrasses, their current and potential uses, and their potential use in developing countries. The future for irrigating turf may rely on the use of moderate- to high-salinity water and, in order to ensure that the turf system is sustainable, will rely on the use of salt-tolerant grasses and an improved knowledge of the effects of salinity on turfgrasses.

  15. Investigations in Marine Chemistry: Salinity I.

    Science.gov (United States)

    Schlenker, Richard M.

    Presented is a unit designed for curriculum infusion and which relies on the hands-on discovery method as an instructive device. The student is introduced to the theory of a functioning salt water conductivity meter. The student explores the resistance of salt water as salinity increases and he treats the data which he has gathered,…

  16. Empirical Relationships Between Electrical Conductivity, Salinity ...

    African Journals Online (AJOL)

    This means that some level of desalination/treatment for the water before consumption would be necessary. On the other hand, the values obtained for Abraka, Ughelli, Oleh and Ozoro fall within the WHO maximum permissible limit for fresh drinking water. KEY WORDS: Electrical Conductivity, Salinity, Density, pH, Water ...

  17. Cuticle hydrocarbons in saline aquatic beetles.

    Science.gov (United States)

    Botella-Cruz, María; Villastrigo, Adrián; Pallarés, Susana; López-Gallego, Elena; Millán, Andrés; Velasco, Josefa

    2017-01-01

    Hydrocarbons are the principal component of insect cuticle and play an important role in maintaining water balance. Cuticular impermeability could be an adaptative response to salinity and desiccation in aquatic insects; however, cuticular hydrocarbons have been poorly explored in this group and there are no previous data on saline species. We characterized cuticular hydrocarbons of adults and larvae of two saline aquatic beetles, namely Nebrioporus baeticus (Dytiscidae) and Enochrus jesusarribasi (Hydrophilidae), using a gas chromatograph coupled to a mass spectrometer. The CHC profile of adults of both species, characterized by a high abundance of branched alkanes and low of unsaturated alkenes, seems to be more similar to that of some terrestrial beetles (e.g., desert Tenebrionidae) compared with other aquatic Coleoptera (freshwater Dytiscidae). Adults of E. jesusarribasi had longer chain compounds than N. baeticus, in agreement with their higher resistance to salinity and desiccation. The more permeable cuticle of larvae was characterized by a lower diversity in compounds, shorter carbon chain length and a higher proportion of unsaturated hydrocarbons compared with that of the adults. These results suggest that osmotic stress on aquatic insects could exert a selection pressure on CHC profile similar to aridity in terrestrial species.

  18. Decline of the world's saline lakes

    Science.gov (United States)

    Wurtsbaugh, Wayne A.; Miller, Craig; Null, Sarah E.; Derose, R. Justin; Wilcock, Peter; Hahnenberger, Maura; Howe, Frank; Moore, Johnnie

    2017-11-01

    Many of the world's saline lakes are shrinking at alarming rates, reducing waterbird habitat and economic benefits while threatening human health. Saline lakes are long-term basin-wide integrators of climatic conditions that shrink and grow with natural climatic variation. In contrast, water withdrawals for human use exert a sustained reduction in lake inflows and levels. Quantifying the relative contributions of natural variability and human impacts to lake inflows is needed to preserve these lakes. With a credible water balance, causes of lake decline from water diversions or climate variability can be identified and the inflow needed to maintain lake health can be defined. Without a water balance, natural variability can be an excuse for inaction. Here we describe the decline of several of the world's large saline lakes and use a water balance for Great Salt Lake (USA) to demonstrate that consumptive water use rather than long-term climate change has greatly reduced its size. The inflow needed to maintain bird habitat, support lake-related industries and prevent dust storms that threaten human health and agriculture can be identified and provides the information to evaluate the difficult tradeoffs between direct benefits of consumptive water use and ecosystem services provided by saline lakes.

  19. Salinity tolerance of germinating alternative oilseeds

    Science.gov (United States)

    Integrating oilseed crops into rotations can improve soil health benefits, nutrient retention, and pollinator provisions. Field margins represent areas where incorporation of oilseeds is feasible. However in the northern Great Plains, field margins can oftentimes be areas of saline soil, which can i...

  20. Salinity transfer in bounded double diffusive convection

    NARCIS (Netherlands)

    Yang, Yantao; van der Poel, Erwin; Ostilla Monico, Rodolfo; Sun, Chao; Verzicco, Roberto; Grossmann, Siegfried; Lohse, Detlef

    2015-01-01

    The double diffusive convection between two parallel plates is numerically studied for a series of parameters. The flow is driven by the salinity difference and stabilised by the thermal field. Our simulations are directly compared with experiments by Hage & Tilgner (Phys. Fluids, vol. 22, 2010,

  1. ASSESSING THE IMPACTS OF SALINITY AND NUTRIENT ...

    Science.gov (United States)

    Healthy seagrass beds were once found throughout the shallow areas of Narragansett Bay, R.I. but have disappeared due to infilling, pollution and disease. In Greenwich Bay, a highly developed embayment within Narragansett Bay, Ruppia maritima has colonized an area on the northern shore once dominated by Zostera marina. This area is sandy, which may allow groundwater seepage. Ruppia is extremely salinity tolerant, and may also be more nutrient tolerant than Zostera. A six week microcosm experiment at two salinity (20 and 30 ppt) and 4 nutrient (0, 5, 10, and 30 µM inorganic N) levels to test their relative tolerance was conducted in 2014. Treatments were renewed daily to simulate tidal flushing and the exposure water was dosed with 15N for the first week of the experiment. At the end of the experiment, the plants were weighed and measured, and dried for later isotopic analysis. In the first experiment, Ruppia had significant structural responses to both nutrients and salinity; there was a slight decline in root weight and a decrease in the total number of shoots with increasing nutrients. Average Ruppia blade length decreased with increasing nutrients and this decrease was more evident at 30 ppt. In contrast, Zostera had no significant structural differences. For both species, there were no differences in shoot or root/rhizome weights in any treatment, nor were there differences in isotopic results due to salinity. However, δ15N in the tissue increase

  2. Microbial amelioration of crop salinity stress.

    Science.gov (United States)

    Dodd, Ian C; Pérez-Alfocea, Francisco

    2012-05-01

    The use of soil and irrigation water with a high content of soluble salts is a major limiting factor for crop productivity in the semi-arid areas of the world. While important physiological insights about the mechanisms of salt tolerance in plants have been gained, the transfer of such knowledge into crop improvement has been limited. The identification and exploitation of soil microorganisms (especially rhizosphere bacteria and mycorrhizal fungi) that interact with plants by alleviating stress opens new alternatives for a pyramiding strategy against salinity, as well as new approaches to discover new mechanisms involved in stress tolerance. Although these mechanisms are not always well understood, beneficial physiological effects include improved nutrient and water uptake, growth promotion, and alteration of plant hormonal status and metabolism. This review aims to evaluate the beneficial effects of soil biota on the plant response to saline stress, with special reference to phytohormonal signalling mechanisms that interact with key physiological processes to improve plant tolerance to the osmotic and toxic components of salinity. Improved plant nutrition is a quite general beneficial effect and may contribute to the maintenance of homeostasis of toxic ions under saline stress. Furthermore, alteration of crop hormonal status to decrease evolution of the growth-retarding and senescence-inducing hormone ethylene (or its precursor 1-aminocyclopropane-1-carboxylic acid), or to maintain source-sink relations, photosynthesis, and biomass production and allocation (by altering indole-3-acetic acid and cytokinin biosynthesis) seem to be promising target processes for soil biota-improved crop salt tolerance.

  3. Hydrologic factors controlling groundwater salinity in northwestern ...

    Indian Academy of Sciences (India)

    The aim of this article is to assess the main factors influencing salinity of groundwater in the coastal area between El Dabaa and Sidi Barani, Egypt. The types and ages of the main aquifers in this area are the fractured limestone of Middle Miocene, the calcareous sandstone of Pliocene and the Oolitic Limestone of ...

  4. Cyclic pressurisation of Mount St Helens dacites and basalt. Laboratory results and implications for lava dome monitoring

    Science.gov (United States)

    Kendrick, Jackie; Dainty, Matthew; Smith, Rosanna; Sammonds, Peter; Pallister, John; Meredith, Phillip

    2010-05-01

    Lava domes are frequently subjected to cyclic heating and pressurisation, which may weaken the dome rocks, leading to renewed extrusion, explosions or collapse. These heating and loading cycles can be recreated in the laboratory, allowing the level of crack damage caused by these cycles to be established through analysing elastic moduli. Acoustic emissions (AEs) indicate the timing of cracking, and can also be used to interpret precursory seismicity for eruption prediction. Experiment samples are from Mount St. Helens, USA: 3 dacites from the Pine Creek eruptive period (2.9-2.55 ka), a Castle Creek age basalt (2.55-1.895 ka), and 4 dacites from the 2004-2008 eruption. Each sample was cut into several cylindrical cores (25 mm diameter and 62.5-70 mm long). Some samples were then heated and cooled at 1˚C/ minute to a target temperature of 600o C or 900o C, and held for 2 hours to achieve thermal equilibrium. This heating can cause cracking due to contrasts in thermal expansion of different minerals. Dynamic elastic moduli were calculated for each sample using ultrasonic wave velocity, density and porosity for later comparison to static elastic moduli gathered during deformation. One core of each sample was loaded to failure in uniaxial compression in order to find the short term strength of the sample. For all cyclic loading tests, conducted on pre-heated and unheated cores, samples were loaded at 10-5 s-1 strain rate then unloaded to 5MPa. Subsequent cycles had an increasing peak load. Most had the same rate for unloading, with a few samples unloaded instantaneously. Axial, radial and volumetric strain were determined from the recorded displacement throughout the experiment and used with the axial stress measurements to calculate static elastic moduli. Samples loaded to failure with no cycling generally failed at higher stresses than their cyclically loaded counter-parts, whilst rapid unloading increased their strength. Failure stresses of the dacite lava dome

  5. The Central Pamir domes as tracer of gravitational disequilibrium and deformation phases forced by deep-seated lithospheric processes

    Science.gov (United States)

    Rutte, Daniel; Fox, Matthew; Ratschbacher, Lothar

    2017-04-01

    Miocene gneiss domes in the Pamir allow unique insight into crustal-scale processes forming the Asian crust of the Pamir-Tibet Plateau. They were exhumed along normal-sense shear zones in an intermittent phase of N-S extension while earlier and later structures document N-S shortening. Recently, Schmidt et al. (2011), Stearns et al., (2013; 2015), Rutte et al. (a & b, accepted), and Hacker et al. (submitted) established a vast structural, petrologic, and geochronologic dataset for the Central Pamir domes. These studies interpreted the domes as a product of gravitational collapse. The dataset includes (micro)structural observations constraining the mechanism of exhumation, thermobarometry of the metamorphic rocks, petrochronologic data constraining timing of pro- and retrogression, a vast multi-method thermochronometric dataset including age-elevation and age-distance data, dates for normal-sense shear zones and barometric data on intrusive rocks. These data constrain the time-temperature, pressure-temperature, and time-pressure history of the dome rocks. We explore the dataset using one-dimensional thermal models. Our code solves the heat transfer equation and gives a transient solution allowing for variation of the geothermal gradient and thermal diffusivity. At this stage, our models suggest that exponential decay of an initially high exhumation rate of 6 km/Myr at 22 Ma to 0.5km/Myr at 13 Ma best explains the dataset. This suggests a one-time input of gravitational potential energy (GPE) that is successively decaying through crustal extension. Both, Asian crustal foundering or Indian slab breakoff may concur with this result. While the Central Pamir domes extend >400 km along strike of the orogen, little variation in timing of most of exhumation during N-S extension is observed. This suggests that the underlying mechanism - be it crustal foundering or slab breakoff - varied little along strike as well. References Hacker, B.R., Ratschbacher, L., Rutte, D

  6. Salinity Trends in the Upper Colorado River Basin Upstream From the Grand Valley Salinity Control Unit, Colorado, 1986-2003

    Science.gov (United States)

    Leib, Kenneth J.; Bauch, Nancy J.

    2008-01-01

    In 1974, the Colorado River Basin Salinity Control Act was passed into law. This law was enacted to address concerns regarding the salinity content of the Colorado River. The law authorized various construction projects in selected areas or 'units' of the Colorado River Basin intended to reduce the salinity load in the Colorado River. One such area was the Grand Valley Salinity Control Unit in western Colorado. The U. S. Geological Survey has done extensive studies and research in the Grand Valley Salinity Control Unit that provide information to aid the U.S. Bureau of Reclamation and the Natural Resources Conservation Service in determining where salinity-control work may provide the best results, and to what extent salinity-control work was effective in reducing salinity concentrations and loads in the Colorado River. Previous studies have indicated that salinity concentrations and loads have been decreasing downstream from the Grand Valley Salinity Control Unit, and that the decreases are likely the result of salinity control work in these areas. Several of these reports; however, also document decreasing salinity loads upstream from the Grand Valley Salinity Control Unit. This finding was important because only a small amount of salinity-control work was being done in areas upstream from the Grand Valley Salinity Control Unit at the time the findings were reported (late 1990?s). As a result of those previous findings, the U.S. Bureau of Reclamation entered into a cooperative agreement with the U.S. Geological Survey to investigate salinity trends in selected areas bracketing the Grand Valley Salinity Control Unit and regions upstream from the Grand Valley Salinity Control Unit. The results of the study indicate that salinity loads were decreasing upstream from the Grand Valley Salinity Control Unit from 1986 through 2003, but the rates of decrease have slowed during the last 10 years. The average rate of decrease in salinity load upstream from the Grand Valley

  7. Three-dimensional ground-water modeling in depositional systems, Wilcox Group, Oakwood salt dome area, east Texas

    Energy Technology Data Exchange (ETDEWEB)

    Fogg, G.E.; Seni, S.J.; Kreitler, C.W.

    1983-01-01

    The data base includes not only measurements of hydraulic head and hydraulic conductivity but also lithofacies maps constructed in a previous study of Wilcox depositional systems. The Carrizo aquifer is a fairly homogeneous sand sheet overlying the much thicker Wilcox Group, a multiple-aquifer system composed primarily of fluvial channel-fill sand bodies distributed among lower permeability interchannel sands and muds. The interconnectedness of the channel-fill sands, which have predictable values of hydraulic conductivity, strongly influences the rate and direction of ground-water flow. Lateral interconnectedness may depend largely on frequency distributions of channel-fill sands (that is, sand percent). Vertical interconnectedness is apparently poor owing to the horizontal stratification of sand and mud. Simulating observed pressure-depth trends by manipulating values of equivalent vertical hydraulic conductivity (K/sub v/') demonstrates that the ratio of vertical to horizontal conductivity (K/sub v/'/K/sub h/') is very low (about 10/sup -3/ to 10/sup -4/). Locally high values of K/sub v/' could result in locally rapid vertical flow, which could in turn be detected using pressure-depth residence times of 10/sup 3/ to 10/sup 4/ years in channel-fill facies and 10/sup 5/ to 10/sup 6/ years in interchannel facies. Because Oakwood Dome is apparently surrounded by interchannel facies as a result of syndepositional dome growth, the dome may be essentially isolated from circulating Wilcox ground water. A possible exception is where channel-fill facies appear to touch or come close to the northeast flank, coinciding with a brackish-water plume that apparently results from dissolution of salt of cap rock. The northeast orientation of the plume appears to be caused by sand-body distribution and interconnection. 38 references.

  8. Interannual surface salinity on Northwest Atlantic shelf

    Science.gov (United States)

    Grodsky, Semyon A.; Reul, Nicolas; Chapron, Bertrand; Carton, James A.; Bryan, Frank O.

    2017-05-01

    Sea surface salinity (SSS) from the Aquarius and SMOS satellite missions displays a steady increase of ˜1 psu over the entire northwestern Atlantic shelf south of Nova Scotia during 2011-2015. Put in the context of longer ocean profile data, the results suggest that mixed layer salinity and temperature north of the Gulf Stream experience positively correlated shelf-wide interannual oscillations (1 psu/2°C). Salty and warm events occur coincident with anomalous easterly-southeasterly winds and Ekman transport counteracting the mean southwestward shelf currents. They are coincident with weakening of both branches of the Scotian Shelf Current (SSC), but only moderately correlate with shifts of the Gulf Stream North Wall. This suggests that salt advection by anomalous SSC acting on the mean salinity gradient is the primary driver regulating the transport of fresh/cold water from high latitudes. The advection mechanism imposes a connectedness of the larger-scale interannual variability in this region and its tie to atmospheric oscillations. In the second part, an analysis of 15 year-long numerical simulations is presented which show eight interannual salinity oscillations (positive and negative). Six of these are driven by horizontal advection by slow varying currents (>2 months), while two events are driven by horizontal eddy advection (<2 months). In line with observations, salt/warm model events correspond to anomalously weak SSC, correlate with southeasterly wind anomaly, and confirm that interannual horizontal salt advection drives interannual salinity. Indeed, vertical exchanges provide negative feedback, while interannual horizontal diffusion and the net surface salt flux anomalies are small.

  9. Proximity of the Superconducting Dome and the Quantum Critical Point in the Two-Dimensional Hubbard Model

    Science.gov (United States)

    Yang, S.-X.; Fotso, H.; Su, S.-Q.; Galanakis, D.; Khatami, E.; She, J.-H.; Moreno, J.; Zaanen, J.; Jarrell, M.

    2011-01-01

    We use the dynamical cluster approximation to understand the proximity of the superconducting dome to the quantum critical point in the two-dimensional Hubbard model. In a BCS formalism, Tc may be enhanced through an increase in the d-wave pairing interaction (Vd) or the bare pairing susceptibility (χ0d). At optimal doping, where Vd is revealed to be featureless, we find a power-law behavior of χ0d(ω=0), replacing the BCS log, and strongly enhanced Tc. We suggest experiments to verify our predictions.

  10. Urban-Dome GHG Monitoring: Challenges and Perspectives from the INFLUX Project

    Science.gov (United States)

    Whetstone, J.; Shepson, P. B.; Davis, K. J.; Sweeney, C.; Gurney, K. R.; Miles, N. L.; Richardson, S.; Lauvaux, T.; Razlivanov, I.; Zhou, Y.; Song, Y.; Turnbull, J. C.; Karion, A.; Cambaliza, M. L.; Callahan, W.; Novakovskaia, E.; Crosson, E.; Rella, C.; Possolo, A.

    2012-04-01

    long wave radiation fluxes. NIST is working with partner institutions to develop the measurement science and measurement tools needed to improve the accuracy and comparability of surface-based measurement approaches for MRV purposes. The current project phase is focused on determination of emission source location with a spatial resolution of approximately 1 km2 and of sources strength to within 20% uncertainty, in part for comparison to inventories. Additionally, the demonstration of a robust, dense observing network methodology will provide a means to characterize urban GHG domes and provides a calibration method for remote sensing measurements whether taken by on-orbit, terrestrial, or airborne observations. The Indianapolis Flux experiment is the initial research effort to demonstrate this approach to emissions verification. Lessons learned in INFLUX are expected to be extensible to other urban and regional settings, suggesting further research to be conducted for areas having significantly different terrain and meteorology.

  11. Associate Directorate Environmental Management Infrastructure Plan for Area G and Area L Domes

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, Patrice Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baumer, Andrew Ronald [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-26

    Technical Area 54, at Los Alamos National Laboratory (LANL) is situated in the east-central portion of the Laboratory on the Mesita del Buey between Pajarito Canyon to the south and Cañada del Buey to the north. TA-54 includes four MDAs designated as G, H, J, and L; a waste characterization, container storage, and transfer facility; active TRU waste and MLLW waste storage and low-level waste (LLW) disposal operations at Area G; active hazardous and mixed low-level (MLLW) waste storage operations at Area L; and administrative and support areas. MDA J has previously under-gone closure. Area G is a waste management and disposal area, used for the disposal and storage of radioactive wastes since 1957. Since August 2015, Area G has been in warm standby and provides minimal operations to support safety, compliance, and nitrate salt remediation. Located within Area G, MDA G covers 63-acres. MDA G contains 334 active and inactive waste management units, which include 36 pits, 294 shafts, and 4 trenches. In 1971, Area G began use for the retrievable storage of TRU waste. There are two pits, four trenches and 60 shafts that contain retrievable TRU waste. Thirty-three of the shafts contain TRU waste that may present unique problems for retrieval. In 1986, segregation of MLLW was initiated at Area G for treatment and temporary storage or for off-site disposal. Area G is the only active LLW disposal facility at the Laboratory. Current operations at Area G include storage and characterization of TRU and mixed TRU waste destined for off-site disposal at the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico and the storage of MLLW destined for off-site treatment and/or disposal. Several above-ground container storage units (CSUs) are currently used for storage of containerized MLLW and/or mixed TRU wastes. These consist of asphalt pads and associated fabric domes or other structures. As defined by the Consent Order, MDA G contains 229 of the 334 subsurface waste

  12. Combining High Resolution InSAR and infrared photogrammetry for studying dome degassing and densification mechanisms at Volcán de Colima, Mexico

    Science.gov (United States)

    Salzer, Jacqueline T.; Milillo, Pietro; Varley, Nick; Perissin, Daniele; Pantaleo, Michele; Walter, Thomas R.

    2017-04-01

    Active volcanoes often display cyclic behaviour with alternating quiescent and eruptive periods. Continuously monitoring volcanic processes such as deformation, seismicity and degassing, irrespective of their current status, is crucial for understanding the parameters governing the fluid transport within the edifice and the transitions between different regimes. However, mapping the deformation and details of fluid escape at the summit of steep sloped volcanoes and integrating these with other types of data is challenging. Here we present for the first time the near-3D surface deformation field derived from high resolution radar interferometry (InSAR) acquired by the satellite TerraSAR-X at a degassing volcano dome and interpret the results in combination with overflight infrared and topographic data. We find that the results strongly differ depending on the chosen InSAR time series method, which potentially overprints the true physical complexities of small scale, shallow deformation processes. We present a new method for accurate mapping of heterogeneities in the dome deformation, and comparison to the topography and precisely located surface temperature anomalies. The identified deformation is dominated by strong but highly localized subsidence of the summit dome. Our results highlight the competing effects of the topography, permeability and shallow volcanic structures controlling the degassing pathways. On small spatial scales compaction sufficiently reduced the dome permeability to redirect the fluid flow. High resolution InSAR monitoring of volcanic domes thus provides valuable data for constraining models of their internal structure, degassing pathways and densification processes.

  13. Hypertonic 3% Saline in Comparison with 0.9% (Normal) Saline in Treatment of Acute Bronchiolitis

    OpenAIRE

    Abdul-karem Jasem Mohammed Al-bahadily; Areege Abdul-abass Mohammed Al-Omrani; Asaad A Atiya

    2017-01-01

    BackgroundBronchiolitis is the commonest cause of lower respiratory tract infection in infant. Respiratory syncytial virus is the commonest cause of bronchiolitis. This study aimed to assess the efficacy of nebulized 3% hypertonic saline and salbutamol in the treatment of acute bronchiolitis in comparison with nebulized 0.9% saline and salbutamol.Materials and MethodsA prospective case second multicenter study was done at two pediatric tertiary centers at the period from 1st of December 2014 ...

  14. Salinity in Water Markets : An ExperimentalInvestigation of the Sunraysia Salinity Levy, Victoria

    OpenAIRE

    C. Duke; L. Gangadharan

    2005-01-01

    Irrigation can have a significant negative impact on the environment. Irrigation impacts contribute a significant portion to the estimated forty six million dollar cost per annum of salinity in the Murray River, Australia. Policies available to regulators include externality taxes and levies. In 2002 the Victorian Government introduced a system of salinity levies in the irrigation regions of Sunraysia, northern Victoria. These levies differ from typical taxes because they also introduce trade...

  15. Global Temperature and Salinity Profile Programme (GTSPP) Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Temperature-Salinity Profile Programme (GTSPP) develops and maintains a global ocean temperature and salinity resource with data that are both up-to-date...

  16. Climate change and soil salinity: The case of coastal Bangladesh.

    Science.gov (United States)

    Dasgupta, Susmita; Hossain, Md Moqbul; Huq, Mainul; Wheeler, David

    2015-12-01

    This paper estimates location-specific soil salinity in coastal Bangladesh for 2050. The analysis was conducted in two stages: First, changes in soil salinity for the period 2001-2009 were assessed using information recorded at 41 soil monitoring stations by the Soil Research Development Institute. Using these data, a spatial econometric model was estimated linking soil salinity with the salinity of nearby rivers, land elevation, temperature, and rainfall. Second, future soil salinity for 69 coastal sub-districts was projected from climate-induced changes in river salinity and projections of rainfall and temperature based on time trends for 20 Bangladesh Meteorological Department weather stations in the coastal region. The findings indicate that climate change poses a major soil salinization risk in coastal Bangladesh. Across 41 monitoring stations, the annual median projected change in soil salinity is 39 % by 2050. Above the median, 25 % of all stations have projected changes of 51 % or higher.

  17. Penaeid Shrimp Salinity Gradient Tank Study 2005-2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We designed an experimental gradient tank to examine salinity preferences of juvenile brown shrimp and white shrimp. Although no strong pattern of salinity avoidance...

  18. Effect of salinity on the bioremediation of petroleum hydrocarbons in a saline-alkaline soil.

    Science.gov (United States)

    Qin, X; Tang, J C; Li, D S; Zhang, Q M

    2012-09-01

     The aim of this paper is to check the effect of salinity on the bioremediation process of petroleum hydrocarbons in the saline-alkaline soil.  In this study, soil salinity was adjusted to different levels by water leaching method and the bioremediation process was conducted for 28 days. Soil pH increased after leaching and decreased during bioremediation process. At initial time, moderate salinity enhanced the biodegradation and addition of microbial consortium was not effective in enhancing degradation rate of petroleum hydrocarbons. At day of 28 days, higher degradation rate was found in treatments with more leaching times with a maximum value of 42·36%. Dehydrogenase activity increased with the progress of bioremediation and positive correlation was found between dehydrogenase activity and degradation rate of petroleum hydrocarbons. Denaturing gradient gel electrophoresis analysis result showed decreased microbial community diversity with increased salt content.  The result suggested that salinity had great impact on bioremediation, and leaching and addition of inoculated consortium were effective in enhancing biodegradation of petroleum hydrocarbons in the saline-alkaline soil.  The result of this study is important for understanding the bioremediation process of petroleum in contaminated soil. New remediation method of petroleum contaminated soil can be developed based on this study. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

  19. COMPARATIVE EFFICACY OF HYPERTONIC SALINE AND NORMAL SALINE SOLUTIONS IN EXPERIMENTALLY INDUCED ENDOTOXIC SHOCK IN DOGS

    Directory of Open Access Journals (Sweden)

    M. A. ZAFAR, G. MUHAMMAD, M. H. HUSSAIN, T. AHMAD, A. YOUSAF AND I. SARFARAZ

    2009-07-01

    Full Text Available This study was contemplated to determine the comparative beneficial effects of hypertonic saline solution and sterile saline solution in induced endotoxic shock in dogs. For this purpose, 12 healthy Mongrel dogs were randomly divided into two equal groups (A and B. All the animals were induced endotoxaemia by slow intravenous administration of Escherichia coli endotoxins 0111:B4. Group A was treated with normal saline solution @ 90 ml/kg BW, while group B was given hypertonic saline solution @ 4 ml/kg BW, followed by normal saline solution @ 10 ml/kg BW. Different parameters were observed for evaluation of these fluids including clinical and haematological parameters, serum electrolytes, mean arterial pressure, and blood gases at different time intervals up to 24 hours post treatments. After infusion of respective fluids, all parameters returned to baseline values in both the groups but group B showed better results than group A except bicarbonates, which better recovered in group A. Thus, it was concluded that a small-volume of hypertonic saline solution could be effectively used in reversing the endotoxaemia. Moreover, it provides a rapid and inexpensive resuscitation from endotoxic shock.

  20. Evaluating physiological responses of plants to salinity stress

    OpenAIRE

    Negr?o, S.; Schm?ckel, S. M.; Tester, M.

    2016-01-01

    Background Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant?s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant?s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. Scope and conclusions We discuss how to quantify the impact of sa...

  1. Morphological responses of forage sorghums to salinity and ...

    African Journals Online (AJOL)

    Significant differences in stem diameter were found between the frequently and the least frequently watered plants, and stem diameter decreased with increasing salinity. Leaf firing increased with increasing salinity reaching 59.9% in the extreme salinity treatment of 15 dS m-1, and it increased with increasing water stress ...

  2. Salinity Gradient Energy: Current State and New Trends

    Directory of Open Access Journals (Sweden)

    Olivier Schaetzle

    2015-06-01

    Full Text Available In this article we give an overview of the state of the art of salinity gradient technologies. We first introduce the concept of salinity gradient energy, before describing the current state of development of the most advanced of these technologies. We conclude with the new trends in the young field of salinity gradient technologies.

  3. Effect of salinity stress on plant fresh weight and nutrient ...

    African Journals Online (AJOL)

    Soil salinity is a major limitation to crop production in many areas of the world. A pot experiment was carried out with rapeseed cultivars in order to investigate the effects of salinity stress on plant development and nutrient composition. For the salinity studies, 150 mM NaCl concentration was applied to12 rapseed cultivars ...

  4. Differential toxicity and influence of salinity on acute toxicity of ...

    African Journals Online (AJOL)

    This study investigated the salinity-tolerance of Oreochromis niloticus and the influence of salinity changes on the acute toxicities of copper sulphate (CuSO4) and lead nitrate (Pb[NO3]2) against the fish species. On the basis of daily mortality assessment, O. niloticus was found to be unable to survive in media with salinity ...

  5. Measurement of salinity and electrical conductivity of some soil ...

    African Journals Online (AJOL)

    The salinity and electrical conductivity of some selected soil samples from Uruan Local government area of Akwa Ibom state of the Federal Republic of Nigeria were measured. The results show that an increase in salinity gives rise to an increase in electrical conductivity. The salinities of the area under study falls within the ...

  6. Salinity ranges of some southern African fish species occurring in ...

    African Journals Online (AJOL)

    The recorded salinity ranges of 96 fish species occurring in southern African estuaries are documented. Factors influen- cing the tolerance of fishes to low and high salinity regimes are discussed, with most species tolerant of low rather than high salinity conditions. This is important since most systems are subject to periodic ...

  7. Partnership for adapting Vulnerable Populations to Soil Salinization ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Soil salinization affects nearly all regions of Sénégal. Nearly a million hectares are affected by salinization and acidification. It is only in the last few years that researchers have understood the relation between soil salinization and climate change. This project aims to increase the capacity of rural communities, ...

  8. Efficacy of nebulised L-adrenaline with 3% hypertonic saline versus normal saline in bronchiolitis

    Directory of Open Access Journals (Sweden)

    Shabnam Sharmin

    2016-08-01

    Full Text Available Background: Bronchiolitis is one of the most common respiratory diseases requiring hospitalization. Nebulized epineph­rine and salbutamol therapy has been used in different centres with varying results. Objective: The objective of the study was to compare the efficacy of nebulised adrenaline diluted with 3% hypertonic saline with nebulised adrenaline diluted with normal saline in bronchiolitis. Methods: Fifty three infants and young children with bronchiolitis, age ranging from 2 months to 2 years, presenting in the emergency department of Manikganj Sadar Hospital were enrolled in the study. After initial evaluation, patients were randomized to receive either nebulized adrenaline I .5 ml ( 1.5 mg diluted with 2 ml of3% hypertonic saline (group I ornebulised adrenaline 1.5 ml (1.5 mg diluted with 2 ml of normal saline (group II. Patients were evaluated again 30 minutes after nebulization. Results: Twenty eight patients in the group I (hypertonic saline and twenty five in groupII (normal saline were included in the study. After nebulization, mean respiratory rate decreased from 63.7 to 48.1 (p<.01, mean clinical severity score decreased from 8.5 to 3.5 (p<.01 and mean oxygen satw·ation increased 94.7% to 96.9% (p<.01 in group I. In group II, mean respiratory rate decreased from 62.4 to 47.4 (p<.01, mean clinical severity score decreased from 7.2 to 4.1 (p<.01 and mean oxygen saturation increased from 94. 7% to 96. 7% (p<.01. Mean respiratory rate decreased by 16 in group I versus 14.8 (p>.05 in group 11, mean clinical severity score decreased by 4.6 in group versus 3 (p<.05 in group, and mean oxygen saturation increased by 2.2% and 1.9% in group and group respectively. Difference in reduction in clinical severity score was statistically significant , though the changes in respiratory rate and oxygen saturation were not statistically significant. Conclusion: The study concluded that both nebulised adrenaline diluted with 3% hypertonic saline and

  9. The lead pollution history of Law Dome, Antarctica, from isotopic measurements on ice cores: 1500 AD to 1989 AD

    Science.gov (United States)

    Vallelonga, P.; Van de Velde, K.; Candelone, J.-P.; Morgan, V. I.; Boutron, C. F.; Rosman, K. J. R.

    2002-11-01

    Lead isotopic compositions and Pb and Ba concentrations have been measured in ice cores from Law Dome, East Antarctica, covering the past 6500 years. 'Natural' background concentrations of Pb (˜0.4 pg/g) and Ba (˜1.3 pg/g) are observed until 1884 AD, after which increased Pb concentrations and lowered 206Pb/ 207Pb ratios indicate the influence of anthropogenic Pb. The isotopic composition of 'natural' Pb varies within the range 206Pb/ 207Pb=1.20-1.25 and 208Pb/ 207Pb=2.46-2.50, with an average rock and soil dust Pb contribution of 8-12%. A major pollution event is observed at Law Dome between 1884 and 1908 AD, elevating the Pb concentration four-fold and changing 206Pb/ 207Pb ratios in the ice to ˜1.12. Based on Pb isotopic systematics and Pb emission statistics, this is attributed to Pb mined at Broken Hill and smelted at Broken Hill and Port Pirie, Australia. Anthropogenic Pb inputs are at their greatest from ˜1900 to ˜1910 and from ˜1960 to ˜1980. During the 20th century, Ba concentrations are consistently higher than 'natural' levels and are attributed to increased dust production, suggesting the influence of climate change and/or changes in land coverage with vegetation.

  10. Percutaneous ultrasound-guided radiofrequency ablation with artificial pleural effusion for hepatocellular carcinoma in the hepatic dome.

    Science.gov (United States)

    Minami, Yasunori; Kudo, Masatoshi; Kawasaki, Toshihiko; Chung, Hobyung; Ogawa, Chikara; Inoue, Tatsuo; Sakaguchi, Yasuhiro; Sakamoto, Hiroki; Shiozaki, Hitoshi

    2003-01-01

    Nodules of hepatocellular carcinoma (HCC) located in the hepatic dome cannot be depicted on ultrasography because of pulmonary air. Therefore, percutaneous treatment is not possible in such cases. The purpose of this study was to clarify the feasibility and safety of percutaneous sonographically guided radiofrequency (RF) ablation with the concurrent use of artificial pleural effusion for HCC located in the right subphrenic region. Between May 2001 and June 2002, 24 patients with 28 HCC nodules located directly below the diaphragm were enrolled in this study. The patient population included 17 men and 7 women (age range, 51-87 years; mean age, 66.5 years). The maximum diameter of the HCC nodules ranged from 1.0 cm to 4 cm (mean +/- SD, 2.1 +/- 0.8 cm). We infused 200-1100 ml of 5% glucose solution intrathoracically to separate the lung and liver; thus, obtaining an image of the whole tumor was impossible on gray-scale sonography. Complete tumor necrosis was achieved in a single session of RF ablation in 27 (96.4%) of the 28 lesions, while two sessions of RF ablation were required for the remaining lesion (3.6%). During treatment, no dyspnea or other complications concerned with the respiratory system were observed. Clinical courses have been satisfactory without recurrences at 1-13 months after treatment (mean, 7.9 months). Percutaneous RF ablation with artificial pleural effusion in patients with HCC in the hepatic dome may be a safe and feasible therapy.

  11. Magma accumulation and segregation during regional-scale folding: The Holland's dome granite injection complex, Damara belt, Namibia

    Science.gov (United States)

    Kruger, Tolene; Kisters, Alexander

    2016-08-01

    The regional-scale, upright fold of the Holland's dome in the Damara belt of central Namibia contains a kilometre-scale network of intrusive, highly fractionated uraniferous leucogranites. Three broadly orthogonal and intersecting sets of leucogranite sheets that intruded parallel and at right angles to the axial plane of the first-order fold can be distinguished. The granites are internally sheeted and illustrate the growth of the injection complex through the successive addition of thousands of smaller magma batches. Spatial and timing relationships point to a stepwise evolution of the injection complex. Early dilatancy-driven segregation and accumulation of granitic magmas in the core of the fold, above a basal detachment, was followed by compaction-driven segregation of a melt phase during fold tightening. The intersecting leucogranite sets provide a suitably organized permeability structure for melt segregation, while the successive injection of magma batches ensures compatibility between regional strain rates during folding and the rates of magma segregation. The three-dimensional network of melt-bearing structures further assisted regional shortening past the lock-up of the fold. The Holland's dome injection complex illustrates the geometric complexity of magma transfer pathways and the significance of regional-scale folding for the accumulation, segregation and fractionation of granitic magmas in suprasolidus crust.

  12. LONG-TERM EVOLUTION OF DOME-SHAPED MACULA: Increased Macular Bulge is Associated With Extended Macular Atrophy.

    Science.gov (United States)

    Soudier, Guillaume; Gaudric, Alain; Gualino, Vincent; Massin, Pascale; Nardin, Mathieu; Tadayoni, Ramin; Speeg-Schatz, Claude; Gaucher, David

    2016-05-01

    Dome-shaped macula (DSM) may cause impaired vision. This study analyzed the long-term evolution of DSM, most particularly macular changes: serous retinal detachment, retinal pigment epithelium atrophy, and DSM bulge increase. Twenty-nine eyes presenting with DSM were retrospectively studied. Clinical data, color photographs, fluorescein angiographs, and optical coherence tomography examinations were reviewed. Patients were followed up from 6 months to 111 months (mean, 37.89 months). The height of the macular bulge, the size of retinal pigment epithelium macular atrophy, and serous retinal detachment progression were studied. Other macular changes were noted. Mean vision remained stable. Dome-shaped macula height increased significantly from 338.9 μm to 364.3 μm (P = 0.007). Serous retinal detachment was present initially in 15 of 29 eyes; it increased in 4 cases and resolved spontaneously in 7. Macular retinal pigment epithelium atrophy correlated with the bulge height (P = 0.015), and it enlarged during follow-up (1.12 vs. 1.34, P = 0.04). Other macular anomalies were present initially or appeared during follow-up: macular pucker, choroidal neovascularization (CNV), subretinal pigmentary clumps, and flat irregular pigmented epithelium detachment. A few treatments were proven in serous retinal detachment cases but were ineffective in restoring vision. In DSM, vision may be stable for years while macular changes progress: the macular bulge increases as does retinal pigment epithelium atrophy.

  13. Precipitation and synoptic regime in two extreme years 2009 and 2010 at Dome C, Antarctica - implications for ice core interpretation

    Science.gov (United States)

    Schlosser, Elisabeth; Stenni, Barbara; Valt, Mauro; Cagnati, Anselmo; Powers, Jordan G.; Manning, Kevin W.; Raphael, Marilyn; Duda, Michael G.

    2016-04-01

    At the East Antarctic deep ice core drilling site Dome C, daily precipitation measurements were initiated in 2006 and are being continued until today. The amounts and stable isotope ratios of the precipitation samples as well as crystal types are determined. Within the measuring period, the two years 2009 and 2010 showed striking contrasting temperature and precipitation anomalies, particularly in the winter seasons. The reasons for these anomalies are analysed using data from the mesoscale atmospheric model WRF (Weather Research and Forecasting Model) run under the Antarctic Mesoscale Prediction System (AMPS). 2009 was relatively warm and moist due to frequent warm air intrusions connected to amplification of Rossby waves in the circumpolar westerlies, whereas the winter of 2010 was extremely dry and cold. It is shown that while in 2010 a strong zonal atmospheric flow was dominant, in 2009 an enhanced meridional flow prevailed, which increased the meridional transport of heat and moisture onto the East Antarctic plateau and led to a number of high-precipitation/warming events at Dome C. This was also evident in a positive (negative) SAM (Southern Annular Mode) index and a negative (positive) ZW3 (zonal wave number three) index during the winter months of 2010 (2009). Changes in the frequency or seasonality of such event-type precipitation can lead to a strong bias in the air temperature derived from stable water isotopes in ice cores.

  14. Automatic Scanning Detection for Characterization of Dome-Related Seismic Swarms at Mount St. Helens and their Evolution Through Time

    Science.gov (United States)

    MacCarthy, J. K.; Rowe, C. A.

    2005-12-01

    Using the waveform data for Mount St. Helens from October 2004 through April, 2005 available from the IRIS DMC, as well as a special data set including the accelerometer that recorded eleven days of activity on the whaleback dome of St. Helens during February, 2005, we have modified a waveform cross-correlation algorithm previously applied for event clustering and repicking into a correlation scanning detector. This tool is being developed for implementation during routine volcano monitoring, as a means of identifying, characterizing and locating repeating swarm events and quantifying their seismic energy release. Application of the scanning detector to St. Helens data reveals stable swarm-type activity over periods with cross-correlation values exceeding 0.8 for 25 days, within which the repeating events slowly evolve over time. Waveforms show high correlation when as much as 60 s of coda is included in the correlation, suggesting very stable source and path characteristics. We present analysis of waveform evolution and event location stability as determined through the detection and automatic repicking and relocation of correlated events. Evolving seismic waveform characteristics are compared to available information about the ongoing eruption sequence to investigate the correspondence among such observables as deformation, volatile flux (both magmagenic and meteoric), estimated dome volume or magma flux and overall energy partitioning. The correlation-detection tool shows promise for real-time implementation, with the potential to greatly reduce analyst workload and augment on-the-fly characterizations already provided by such routine monitoring tools as RSAM and SSAM.

  15. "Albedo dome": a method for measuring spectral flux-reflectance in a laboratory for media with long optical paths.

    Science.gov (United States)

    Light, Bonnie; Carns, Regina C; Warren, Stephen G

    2015-06-10

    A method is presented for accurate measurement of spectral flux-reflectance (albedo) in a laboratory, for media with long optical path lengths, such as snow and ice. The approach uses an acrylic hemispheric dome, which, when placed over the surface being studied, serves two functions: (i) it creates an overcast "sky" to illuminate the target surface from all directions within a hemisphere, and (ii) serves as a platform for measuring incident and backscattered spectral radiances, which can be integrated to obtain fluxes. The fluxes are relative measurements and because their ratio is used to determine flux-reflectance, no absolute radiometric calibrations are required. The dome and surface must meet minimum size requirements based on the scattering properties of the surface. This technique is suited for media with long photon path lengths since the backscattered illumination is collected over a large enough area to include photons that reemerge from the domain far from their point of entry because of multiple scattering and small absorption. Comparison between field and laboratory albedo of a portable test surface demonstrates the viability of this method.

  16. Correlation of Fracture Behavior With Microstructure in Friction Stir Welded, and Spin Formed AI-Li 2195 Domes

    Science.gov (United States)

    Tayon, Wesley A.; Domack, Marcia S.; Hales, Stephen J.

    2012-01-01

    Single-piece, spin-formed domes manufactured from friction stir welded (FSW) plates of Al-Li alloy 2195 have the potential to reduce the cost of fabricating cryogenic propellant tanks. Mechanical properties in the completed domes can be related directly to the final material condition and the microstructures developed. However, these new fabrication techniques have resulted in unexpected material challenges, such as abnormal grain growth in the weld nugget and the propensity for fracture in the adjacent thermo-mechanically affected zone (TMAZ). In this study, the microstructure and texture transformations within the TMAZ are related to fracture location in the vicinity of the weldment. The texture variations in the TMAZ are caused primarily by the varying amounts of shear deformation introduced during the FSW process. Grain morphology and microtexture characteristics are examined as a function of location in the TMAZ via electron backscatter diffraction (EBSD). A strong correlation between fracture location and the presence of texture banding in the TMAZ is observed. The fracture path tends to follow a distinct region of low Taylor Factor (TF) grains.

  17. The Friction of Saline Ice on Aluminium

    Directory of Open Access Journals (Sweden)

    Christopher Wallen-Russell

    2016-01-01

    Full Text Available The friction of ice on other materials controls loading on offshore structures and vessels in the Arctic. However, ice friction is complicated, because ice in nature exists near to its melting point. Frictional heating can cause local softening and perhaps melting and lubrication, thus affecting the friction and creating a feedback loop. Ice friction is therefore likely to depend on sliding speed and sliding history, as well as bulk temperature. The roughness of the sliding materials may also affect the friction. Here we present results of a series of laboratory experiments, sliding saline ice on aluminium, and controlling for roughness and temperature. We find that the friction of saline ice on aluminium μice-al=0.1 typically, but that this value varies with sliding conditions. We propose physical models which explain the variations in sliding friction.

  18. Limnological study of a Pantanal saline lake

    Directory of Open Access Journals (Sweden)

    P. B. Medina-Júnior

    Full Text Available Limnological studies involving physical, chemical and biological aspects, with emphasis on the zooplankton community, were carried out in a saline lake of the Pantanal floodplain, in the subregion of Nhecolândia (Mato Grosso do Sul, Brazil, during the dry and wet seasons of the local hydrological cycle. The results show that the lake is not directly affected by the flood-pulse through superficial coalescence, probably receiving groundwater instead. Most of the measured variables showed extremely high values, particularly dissolved salts, pH, conductivity, nutrients and chlorophyll a. These values were highest during the dry period due to the system's low water volume. The zooplankton community was basically represented by Metacyclops mendocinus, which displayed high population densities throughout the periods studied. The low diversity recorded is congruent with other studies on continental saline water-bodies.

  19. Limnological study of a Pantanal saline lake.

    Science.gov (United States)

    Medina-Júnior, P B; Rietzler, A C

    2005-11-01

    Limnological studies involving physical, chemical and biological aspects, with emphasis on the zooplankton community, were carried out in a saline lake of the Pantanal floodplain, in the subregion of Nhecolândia (Mato Grosso do Sul, Brazil), during the dry and wet seasons of the local hydrological cycle. The results show that the lake is not directly affected by the flood-pulse through superficial coalescence, probably receiving groundwater instead. Most of the measured variables showed extremely high values, particularly dissolved salts, pH, conductivity, nutrients and chlorophyll a. These values were highest during the dry period due to the system's low water volume. The zooplankton community was basically represented by Metacyclops mendocinus, which displayed high population densities throughout the periods studied. The low diversity recorded is congruent with other studies on continental saline water-bodies.

  20. Saline Nasal Irrigation for Upper Respiratory Conditions

    Science.gov (United States)

    2009-01-01

    Acute and chronic upper respiratory conditions are common and expensive disorders with enormous impact on patient quality of life and society at large. Saline nasal irrigation (SNI), a therapy with roots in Ayurvedic medicine that bathes the nasal mucosa with in spray or liquid saline, has been used as adjunctive care for upper respiratory conditions. In liquid form, SNI has been found to be effective adjunctive care by the Cochrane Collaboration for symptoms associated with chronic rhinosinusitis. Less conclusive clinical trial evidence supports its use in spray and liquid forms as adjunctive treatment for mild-to-moderate allergic rhinitis and acute upper respiratory infections. Consensus or expert opinion recommendations exist for SNI as a treatment for a variety of other conditions including rhinitis of pregnancy. SNI appears safe; side effects are minimal and transient. It can be recommended by clinicians to interested patients with a range of upper respiratory conditions in the context of patient education and printed instructional handouts. PMID:19904896

  1. Cold, salinity and drought stresses: an overview.

    Science.gov (United States)

    Mahajan, Shilpi; Tuteja, Narendra

    2005-12-15

    World population is increasing at an alarming rate and is expected to reach about six billion by the end of year 2050. On the other hand food productivity is decreasing due to the effect of various abiotic stresses; therefore minimizing these losses is a major area of concern for all nations to cope with the increasing food requirements. Cold, salinity and drought are among the major stresses, which adversely affect plants growth and productivity; hence it is important to develop stress tolerant crops. In general, low temperature mainly results in mechanical constraint, whereas salinity and drought exerts its malicious effect mainly by disrupting the ionic and osmotic equilibrium of the cell. It is now well known that the stress signal is first perceived at the membrane level by the receptors and then transduced in the cell to switch on the stress responsive genes for mediating stress tolerance. Understanding the mechanism of stress tolerance along with a plethora of genes involved in stress signaling network is important for crop improvement. Recently, some genes of calcium-signaling and nucleic acid pathways have been reported to be up-regulated in response to both cold and salinity stresses indicating the presence of cross talk between these pathways. In this review we have emphasized on various aspects of cold, salinity and drought stresses. Various factors pertaining to cold acclimation, promoter elements, and role of transcription factors in stress signaling pathway have been described. The role of calcium as an important signaling molecule in response to various stress signals has also been covered. In each of these stresses we have tried to address the issues, which significantly affect the gene expression in relation to plant physiology.

  2. Limnological study of a Pantanal saline lake

    OpenAIRE

    Medina-Júnior,P. B.; A. C. Rietzler

    2005-01-01

    Limnological studies involving physical, chemical and biological aspects, with emphasis on the zooplankton community, were carried out in a saline lake of the Pantanal floodplain, in the subregion of Nhecolândia (Mato Grosso do Sul, Brazil), during the dry and wet seasons of the local hydrological cycle. The results show that the lake is not directly affected by the flood-pulse through superficial coalescence, probably receiving groundwater instead. Most of the measured variables showed extre...

  3. Modelling souring in a high salinity reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Michael; Crossland, Alan; Stott, Jim

    2006-03-15

    CAPCIS Ltd (Capcis) have developed a souring model for use in highly saline reservoirs where salinity limits the growth of sulphate reducing bacteria (SRB). Capcis have successfully applied the model to a field in North Africa. The conceptual basis of the model considers the course of the H2S from generation in the reservoir including dilution, sulphide retardation and scavenging and H2S fluid phase partitioning. At each stage mathematical equations governing the behaviour of the H2S were produced. In order to estimate the potential for H2S generation, it is required to know the chemistry of the injection and formation waters, as well as the properties of the indigenous SRB, i.e. the maximum salinity for their growth. This is determined by bottle testing of H2S generation by SRB at a range of injection/formation water ratios. The maximum salinity for SRB growth then determines the mixing ratios at which H2S generation takes place. Sulphide retardation due to adsorption at immobile interfaces was empirically modeled from reservoir data. Sulphide scavenging due to reaction with iron generated from corrosion was also modelled. Reservoir mineral scavenging was not modelled but could be incorporated in an extension to the model. Finally, in order to compute the gas-phase concentration of generated H2S, the H2S in the well stream is partitioned between the gas, oil and water phases. Capcis has carried out detailed computations of H2S solubility in crude oil and formation waters and the derivation of distribution ratios based on the respective partition coefficients using Gerard's line method, a modification of Henry's Law. (author) (tk)

  4. GPR Phase Response to Fracture Saline Tracers

    Science.gov (United States)

    Tsoflias, G. P.; Becker, M.

    2016-12-01

    Flow in fractured rock is highly heterogeneous and difficult to predict. Groundwater, geothermal and hydrocarbon resource development requires knowledge of fracture fluid flow properties. Geophysical methods such as seismic, electrical and electromagnetic, have been used to image fracture systems. Ground penetrating radar (GPR) has been shown to image fractures and monitor saline tracers in groundwater aquifers. Previous studies have considered primarily the amplitude response of GPR signals. In this work we examine the phase response of GPR in a series of controlled field experiments spanning over a decade. We compare field observations to analytical models and FDTD numerical simulations of the phase response of GPR signals to saline tracers in fractures. We show that changes in the electrical conductivity of fracture fluid cause predictable and detectable phase changes in reflected and transmitted GPR signals through fractures. Lower frequency signals (MHz range) show greater sensitivity to fluid electrical conductivity changes, while being relatively insensitive to fracture aperture. Phase changes over time (time lapse) are used to image channeled flow through discrete fractures and to monitor tracer breakthrough. Although GPR is used extensively in near-surface groundwater investigations, deployment in boreholes can allow adaptation of the technology to monitor saline tracers in hydrocarbon and geothermal systems.

  5. Incorporation of salinity in Water Availability Modeling

    Science.gov (United States)

    Wurbs, Ralph A.; Lee, Chihun

    2011-10-01

    SummaryNatural salt pollution from geologic formations in the upper watersheds of several large river basins in the Southwestern United States severely constrains the use of otherwise available major water supply sources. The Water Rights Analysis Package modeling system has been routinely applied in Texas since the late 1990s in regional and statewide planning studies and administration of the state's water rights permit system, but without consideration of water quality. The modeling system was recently expanded to incorporate salinity considerations in assessments of river/reservoir system capabilities for supplying water for environmental, municipal, agricultural, and industrial needs. Salinity loads and concentrations are tracked through systems of river reaches and reservoirs to develop concentration frequency statistics that augment flow frequency and water supply reliability metrics at pertinent locations for alternative water management strategies. Flexible generalized capabilities are developed for using limited observed salinity data to model highly variable concentrations imposed upon complex river regulation infrastructure and institutional water allocation/management practices.

  6. Performance of skylight illuminance inside a dome shaped adobe house under composite climate at New Delhi (India: A typical zero energy passive house

    Directory of Open Access Journals (Sweden)

    Arvind Chel

    2014-06-01

    Full Text Available This paper presents annual experimental performance of pyramid shaped skylight for daylighting of a dome shaped adobe house located at solar energy park in New Delhi (India. This approach of single story dome shaped building with skylight is more useful for rural and semi-urban sectors for both office and residential buildings reducing artificial lighting energy consumption. The hourly measured data of inside and outside illuminance for three different working surface levels inside the existing rooms are presented for each month of the year. The embodied energy payback time of the skylight is also determined on the basis of lighting energy saving potential.

  7. 3-D assessment of peak-metamorphic conditions by Raman spectroscopy of carbonaceous material: an example from the margin of the Lepontine dome (Swiss Central Alps)

    DEFF Research Database (Denmark)

    Wiederkehr, Michael; Bousquet, Romain; Ziemann, Martin

    2011-01-01

    within the northeastern margin of the Lepontine dome and easterly adjacent areas of the Swiss Central Alps. Three-dimensional mapping of isotemperature contours in map and profile views shows that the isotemperature contours associated with the Miocene Barrow-type Lepontine metamorphic event cut across...... refolded nappe contacts, both along and across strike within the northeastern margin of the Lepontine dome and adjacent areas. Further to the northeast, the isotemperature contours reflect temperatures reached during the Late Eocene subduction-related blueschist-facies event and/or during subsequent near...

  8. Evaluating physiological responses of plants to salinity stress

    Science.gov (United States)

    Negrão, S.; Schmöckel, S. M.; Tester, M.

    2017-01-01

    Background Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant’s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant’s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. Scope and conclusions We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant’s response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments. PMID:27707746

  9. Evaluating physiological responses of plants to salinity stress

    KAUST Repository

    Negrão, Sónia

    2016-10-06

    Background Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant’s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant’s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. Scope and conclusions We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant’s response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments.

  10. Evaluating physiological responses of plants to salinity stress.

    Science.gov (United States)

    Negrão, S; Schmöckel, S M; Tester, M

    2017-01-01

    Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant's physiology, making it difficult to study in toto Instead, it is more tractable to dissect the plant's response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant's response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company.

  11. Impacts of a Saline Lake and Its Salinity on Local Precipitation

    Directory of Open Access Journals (Sweden)

    Lijuan Wen

    2015-01-01

    Full Text Available In the study, the weather research and forecasting model coupled with the community land model (WRF-CLM is used to investigate impacts of the GSL and its salinity from October 2001 to April 2002. A salinity parameterization scheme is incorporated into the lake scheme of CLM. The WRF-CLM model with the salinity parameterization scheme can better simulate temperature and precipitation compared to that without considering the salinity effects. The improvement of simulation is especially significant under cold weather condition. The precipitation caused by the GSL effect is always positive over the downwind area of the GSL during the study period. Increased precipitation is largely attributed to the warm lake surface temperature and high latent heat flux over the GSL, which are favorable for the development of strong convective activity and horizontal wind and moisture convergence. Such kind of GSL-induced forcing is the primary mechanism for the downstream GSL effect precipitation. The GSL effect precipitation is largely contributed by fresh water effect when the temperature is close to or higher than 0°C. However, with lower temperature, the salinity effect becomes dominant for the GSL effect precipitation.

  12. Extensional flow produces recumbent folds in syn-orogenic granitoids (Padrón migmatitic dome, NW Iberian Massif)

    Science.gov (United States)

    Fernández, Rubén Díez; Parra, Luis Miguel Martín; Rubio Pascual, Francisco J.

    2017-04-01

    This contribution provides a case example on the generation of large-scale recumbent folds in syn-orogenic granitoids. We analyze the progressive reworking of extension-related structures into later ones after a period of crustal thickening. The Padrón migmatitic dome formed after the climax of the Gondwana-Laurussia collision in the late Paleozoic. Petrostructural analysis carried out in the eastern flank of this dome reveals that extensional flow resulted in progressive exhumation of mainland Gondwana, which rested under peri-gondwanan allochthonous terranes and a suture zone during maximum crustal thickening. Exhumation proceeded up to upper crust levels (andalusite stability field) along with partial melting of the middle-lower crust and with the generation of granitoid laccoliths during an early extensional stage. Newly-formed lithological and mechanical anisotropies, such as the presence of variably-sized sheet-shaped bodies of syn-orogenic granitoids, provided a favorable rheological setting for fold nucleation during the intermediate stages of extension. In extending orogenic crust, whether recumbent folds occur after significant melt production depends on the lateral/vertical flow ratio, and on the orientation of deforming bodies with regard to kinematic/strain axes. We suggest that subhorizontal extensional flow dominated over vertical flow during the early and intermediate stages of the evolution of the Padrón dome. A component of vertical (diapiric) flow caused progressive tilting of the sheet-like bodies and obliquity respect to strain axes. This resulted in the development of regional-scale folds at the expense of syn-orogenic granitoids, such as in the case of the Portomouro recumbent synform. Extensional ductile flow was oblique to the trend of the orogen during the whole process, and directed to the NNW during the formation of recumbent folds. Non-coaxial shearing favored an (NNW-SSE) elongate shape for the syn-kinematic granitic massifs as well

  13. An experimental insight into the evolution of permeability at high temperatures and applications for shallow conduit and lava dome degassing

    Science.gov (United States)

    Chadderton, Amy; Sammonds, Peter; Meredith, Philip; Smith, Rosanna; Tuffen, Hugh; Gaunt, Elizabeth

    2016-04-01

    Two recent eruptions in Chile, at Chaitén Volcano in 2008-10 and Cordón Caulle in 2011-12, allowed the first detailed observations of rhyolitic activity and provided insights into the evolution of highly silicic eruptions. Both events exhibited simultaneous explosive and effusive activity, with both lava and ash plumes emitted from the same vent [1]. The permeability of fracture networks that act as fluid flow pathways is key to understanding such eruptive behaviour. Here, we report results from a systematic experimental investigation of permeability in volcanic rocks at magmatic temperatures and pressures, in the presence of pore fluids using our newly-developed high-temperature permeability facility. Enhancements to the High Temperature Triaxial Deformation Cell at UCL [2] have enabled us to make permeability measurements on 25mm x 50mm cores at both elevated temperature and elevated hydrostatic pressure [3]. We present results from several suites of permeability measurements on samples of dome dacite from the 2004-08 eruption of Mount St Helens, and rhyolite collected from the lava dome formed during the 2008-10 eruption of Chaitén, Chile. Tests were conducted at temperatures up to 900oC and under an effective pressure of 5 MPa, using the steady-state flow technique. Samples were cooled to room temperature between each high temperature test, and the permeability of each sample was re-measured before heating to the next temperature increment in the series. Additional longer duration high temperature tests were also conducted to investigate the development of a permeable network at high temperatures over time. The results show a complex permeability evolution that includes a reduction in permeability by approximately 3 orders of magnitude up to 600oC. Together with thermal cracking tests, AE data and SEM/thin section analysis these new experimental permeability results are applied to enhance our understanding of the complex issue of shallow conduit and lava

  14. Review of Water Salinity Measurement Methods and Considering Salinity in Measuring Water Area Phase Fraction of Wet Gas

    Directory of Open Access Journals (Sweden)

    Hossein SERAJ

    2014-01-01

    Full Text Available Accurate measurement of water area phase fraction is one of key factors for precise measuring of wet gas flow rate. As variation in water salinity affects water area phase fraction measurement, therefore for having accurate water area phase fraction measurement, it is required to measure water salinity and take that into account in water area phase fraction measurement. In this paper, various methods for measuring water salinity in wet gas fluid are reviewed. Then the methodology for considering measured water salinity in water area phase fraction measurement is explained. Since accurate measurement of water area phase fraction is necessary for having precise wet gas flow rate measurement, therefore by considering water salinity in water area phase fraction measurement, the overall accuracy of wet gas measurement increases. In addition, knowing water salinity is very valuable in wet gas flow measurement as water breakthrough can be sensed using the measured salinity.

  15. Durum wheat seedlings in saline conditions: Salt spray versus root-zone salinity

    Science.gov (United States)

    Spanò, Carmelina; Bottega, Stefania

    2016-02-01

    Salinity is an increasingly serious problem with a strong negative impact on plant productivity. Though many studies have been made on salt stress induced by high NaCl concentrations in the root-zone, few data concern the response of plants to saline aerosol, one of the main constraints in coastal areas. In order to study more in depth wheat salinity tolerance and to evaluate damage and antioxidant response induced by various modes of salt application, seedlings of Triticum turgidum ssp. durum, cv. Cappelli were treated for 2 and 7 days with salt in the root-zone (0, 50 and 200 mM NaCl) or with salt spray (400 mM NaCl + 0 or 200 mM NaCl in the root-zone). Seedlings accumulated Na+ in their leaves and therefore part of their ability to tolerate high salinity seems to be due to Na+ leaf tissue tolerance. Durum wheat, confirmed as a partially tolerant plant, shows a higher damage under airborne salinity, when both an increase in TBA-reactive material (indicative of lipid peroxidation) and a decrease in root growth were recorded. A different antioxidant response was activated, depending on the type of salt supply. Salt treatment induced a depletion of the reducing power of both ascorbate and glutathione while the highest contents of proline were detected under salt spray conditions. In the short term catalase and ascorbate peroxidase co-operated with glutathione peroxidase in the scavenging of hydrogen peroxide, in particular in salt spray-treated plants. From our data, the durum wheat cultivar Cappelli seems to be sensitive to airborne salinity.

  16. Salinity trends in the Ebro River (Spain)

    Science.gov (United States)

    Lorenzo-Gonzalez, M.° Angeles; Isidoro, Daniel; Quilez, Dolores

    2016-04-01

    In the Ebro River Basin (Spain), the increase in water diversion for irrigation (following the increase in irrigated area) and the recovery of natural vegetation in the upper reaches, along with climate change have induced changes in the river flow and its associated salt loads. This study was supported by the Ebro River Basin Administration (CHE) and aimed to establish the trends in the salt concentrations and loads of the Ebro River at Tortosa (no 027, the extreme downstream gauging station). The CHE databases from 1972-73 to 2011-12, including mean monthly flows (Q) and concentration readings (electrical conductivity converted to total dissolved solids -TDS- by regression) from monthly grab samples, have been used. The trends were established by (i) harmonic regression analysis; (ii) linear regression by month; and (iii) the non-parametric Mann-Kendall method. Additionally, (iv) the regressions of TDS on Q in the current and previous months were established, allowing for analyzing separately the trends in TDS linked to- (TDSq) and independent of- (TDSaj) the observed changes in flow. In all cases, the trends were analyzed for different periods within the full span 1973-2012 (1973 to 2012, 1981 to 2012, 1990-2012 and 2001-2012), trying to account for periods with sensibly similar patterns of land use change. An increase in TDS was found for all the periods analyzed that was lower as shorter periods were used, suggesting that lower salinity changes might be taking place in the last years, possibly due to the reduction in the rate of irrigation development and to the on-going irrigation modernization process. The higher seasonal TDS increases were found in autumn and winter months and the increase in TDS was linked both to intrinsic changes in salinity (TDSaj) and to the observed decrease in flow (TDSq). On the other hand, the salt loads decreased, especially in autumn, as a result of the observed flow decrease. These results are based on the observed evolution of

  17. The Aquarius Salinity Retrieval Algorithm: Early Results

    Science.gov (United States)

    Meissner, Thomas; Wentz, Frank J.; Lagerloef, Gary; LeVine, David

    2012-01-01

    The Aquarius L-band radiometer/scatterometer system is designed to provide monthly salinity maps at 150 km spatial scale to a 0.2 psu accuracy. The sensor was launched on June 10, 2011, aboard the Argentine CONAE SAC-D spacecraft. The L-band radiometers and the scatterometer have been taking science data observations since August 25, 2011. The first part of this presentation gives an overview over the Aquarius salinity retrieval algorithm. The instrument calibration converts Aquarius radiometer counts into antenna temperatures (TA). The salinity retrieval algorithm converts those TA into brightness temperatures (TB) at a flat ocean surface. As a first step, contributions arising from the intrusion of solar, lunar and galactic radiation are subtracted. The antenna pattern correction (APC) removes the effects of cross-polarization contamination and spillover. The Aquarius radiometer measures the 3rd Stokes parameter in addition to vertical (v) and horizontal (h) polarizations, which allows for an easy removal of ionospheric Faraday rotation. The atmospheric absorption at L-band is almost entirely due to O2, which can be calculated based on auxiliary input fields from numerical weather prediction models and then successively removed from the TB. The final step in the TA to TB conversion is the correction for the roughness of the sea surface due to wind. This is based on the radar backscatter measurements by the scatterometer. The TB of the flat ocean surface can now be matched to a salinity value using a surface emission model that is based on a model for the dielectric constant of sea water and an auxiliary field for the sea surface temperature. In the current processing (as of writing this abstract) only v-pol TB are used for this last process and NCEP winds are used for the roughness correction. Before the salinity algorithm can be operationally implemented and its accuracy assessed by comparing versus in situ measurements, an extensive calibration and validation

  18. Effects of Salinity and Nutrient Addition on Mangrove Excoecaria agallocha

    Science.gov (United States)

    Chen, Yaping; Ye, Yong

    2014-01-01

    Effects of salinity on seed germination and growth of young (1 month old) and old (2-year old) seedlings of Excoecaria agallocha were investigated. Combined effects of salinity and nutrient level were also examined on old seedlings. Seed germination was best at 0 and 5 psu salinity. 15 psu salinity significantly delayed root initiation and decreased final establishment rate. All seeds failed to establish at 25 psu salinity. Young seedlings performed best at 0 and 5 psu, but growth was stunned at 15 psu, and all seedlings died within 90 days at 25 psu. Old seedlings grew best at salinities below 5 psu and they survived the whole cultivation at 25 psu. This indicated that E. agallocha increased salt tolerance over time. Gas exchange was significantly compromised by salinities above 15 psu but evidently promoted by high nutrient. Proline accumulated considerably at high nutrient, and its contents increased from 0 to 15 psu but decreased at 25 psu salinity. Lipid peroxidation was aggravated by increasing salinity beyond 15 psu but markedly alleviated by nutrient addition. These responses indicated that E. agallocha was intolerant to high salinity but it can be greatly enhanced by nutrient addition. PMID:24691495

  19. Synthesis and characterization of PdAg as a catalyst for oxygen reduction reaction in acid medium; Sintesis y caracterizacion de PdAg como catalizador para la reaccion de reduccion de oxigeno en medio acido

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Casillas, D. C.; Vazquez-Huerta, G.; Solorza-Feria, O. [Centro de Investigacion y de Estudios Avanzados del IPN, Mexico D.F. (Mexico)]. E-mail: dcmartinez@cinvestav.mx

    2009-09-15

    This work presents the synthesis of the binary compound PdAg and the electrochemical characterization for oxygen reduction reaction (ORR) in acid medium. The catalyst is obtained from the reduction of Pd(NO{sub 3}){sub 2}·2H{sub 2}O and AgNO{sub 3} with NaBH{sub 4} in THF. The synthesized compound was physically characterized with transmission electron microscopy (TEM), sweep electron microscopy (SEM) and x-ray diffraction (XRD) of powder. Electrochemical studies were conducted to determine the catalytic activity and intrinsic properties of the PdAg material for the ORR in acid medium using cyclic voltamperometry (CV), rotary disc electrode (RDE) and electrochemical impedance spectroscopy (EIS) in a solution of H{sub 2}SO{sub 4} 0.5 M at 25 degrees Celsius. The electrochemical current-potential responses were compared to those of palladium and platinum. The kinetic results showed an increase in the performance of the bimetallic electrocatalyst containing Ag as compared to pure Pd, but less than that obtained with nanometric Pt. The Tafel slopes obtained are roughly120 mV dec-1, similar to that reported for Pt and Pd and for other Ru-based electrocatalysts. [Spanish] En este trabajo se presentan la sintesis del compuesto binario PdAg y su caracterizacion electroquimica para la reaccion de reduccion de oxigeno (RRO) en medio acido. El catalizador se obtuvo a partir de la reduccion de Pd(NO{sub 3}){sub 2}·2H{sub 2}O y AgNO{sub 3} con NaBH{sub 4} en THF. El compuesto sintetizado se caracterizo fisicamente por microscopia electronica de transmision (MET), microscopia electronica de barrido (MEB) y difraccion de rayos X (DRX) de polvos. Se realizaron estudios electroquimicos para determinar la actividad catalitica y las propiedades intrinsecas del material de PdAg para la reaccion de reduccion de oxigeno (RRO) en medio acido, utilizando las tecnicas de voltamperometria ciclica (VC), electrodo disco rotatorio (EDR) y espectroscopia de impedancia electroquimica (EIE), en

  20. Synthesis and characterization of cobalt oxide and titanium mixtures using mechanical alloying and its response to oxygen reduction; Sintesis y caracterizacion de mezclas de oxidos de cobalto y titanio por aleado mecanico y su respuesta para la reduccion de oxigeno

    Energy Technology Data Exchange (ETDEWEB)

    Basurto S, R.; Bonifacio-Martinez, J.; Fernandez, S.M [Instituto Nacional de Investigaciones Nucleares, Ocoyoacac, Estado de Mexico (Mexico)]. E-mail: rafael.basurto@inin.gob.mx

    2009-09-15

    The synthesis of Co{sub 3}O{sub 4} and CoTiO{sub 3} oxides was conducted using mechanical alloying and combustion. Co{sub 3}O{sub 4} used was obtained using a SPEX ball mill with cobalt nitrate, Co(NO{sub 3})36H{sub 2}O plus urea, CH{sub 4}N{sub 2}O, in a molar ratio of 1:1 and a ball weight ratio of 1:4 with grinding times of 2.5 hours in an argon atmosphere. The material obtained after alloying underwent combustion at 400 degrees Celsius and 500 degrees Celsius, obtaining oxides of mixed cobalt valence. This material was mixed with TiO{sub 2} with a weight ratio of 1:1 and was mechanically alloyed with a ball weight ratio of 1:8; grinding was performed for 2.5 hours in argon atmosphere and it underwent combustion at 800 degrees Celsius. Characterization was performed using x-ray diffraction, low-vacuum sweep electron microscopy and EDS. The electrochemical performance was obtained in a galvanostat-potentiostat (Princenton Applied Research modelo 273). Both materials present electrocatalytic activity for oxygen reduction reaction in alkaline medium. [Spanish] La sintesis de los oxidos: Co{sub 3}O{sub 4} y CoTiO3 se realizo por la tecnica de aleado mecanico y combustion. El Co{sub 3}O{sub 4} utilizado, se obtuvo por con un molino de bolas SPEX, utilizando nitrato de cobalto, Co(NO{sub 3})36H{sub 2}O mas urea, CH{sub 4}N{sub 2}O, en una relacion molar 1:1.y una relacion en peso de bolas de 1:4 con tiempos de molienda de 2.5 horas, en atmosfera de argon, al termino del aleado el material obtenido se llevo a combustion a 400 grados centigrados y 500 grados centigrados, obteniendose el oxido de valencia mixta de cobalto. Este material se mezclo con TiO{sub 2}, en una relacion en peso de 1:1 y se aleo mecanicamente, con una relacion en peso de bolas de 1:8, por 2.5 horas de molienda en atmosfera de argon y llevandolo a combustion a 800 grados centigrados. La caracterizacion se hizo por: Difraccion de Rayos X, Microscopia Electronica de Barrido de Bajo Vacio y EDS El