Sample records for submarine reactor compartments

  1. Request for interim approval to operate Trench 94 of the 218-E-12B Burial Ground as a chemical waste landfill for disposal of polychlorinated biphenyl waste in submarine reactor compartments. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Cummins, G.D.


    This request is submitted to seek interim approval to operate a Toxic Substances Control Act (TSCA) of 1976 chemical waste landfill for the disposal of polychlorinated biphenyl (PCB) waste. Operation of a chemical waste landfill for disposal of PCB waste is subject to the TSCA regulations of 40 CFR 761. Interim approval is requested for a period not to exceed 5 years from the date of approval. This request covers only the disposal of small 10 quantities of solid PCB waste contained in decommissioned, defueled submarine reactor compartments (SRC). In addition, the request applies only to disposal 12 of this waste in Trench 94 of the 218-E-12B Burial Ground (Trench 94) in the 13 200 East Area of the US Department of Energy`s (DOE) Hanford Facility. Disposal of this waste will be conducted in accordance with the Compliance 15 Agreement (Appendix H) between the DOE Richland Operations Office (DOE-RL) and 16 the US Environmental Protection Agency (EPA), Region 10. During the 5-year interim approval period, the DOE-RL will submit an application seeking final 18 approval for operation of Trench 94 as a chemical waste landfill, including 19 any necessary waivers, and also will seek a final dangerous waste permit from 20 the Washington State Department of Ecology (Ecology) for disposal of lead 21 shielding contained in the SRCS.

  2. [Effect of noise in submarine compartment on signal discrimination and arithmetic performance]. (United States)

    Hu, Z; Liang, Z; Shi, X; Tang, Z


    To study the effects of noise level in submarine compartment on signal discrimination and arithmetic performance, experiments were carried out on 13 subjects. The results showed that as noise level raised from moderate (73 dBA) to higher levels (85-92 dBA), work efficiency showed a progressive decrease, but when noise level reached 96 dBA the decrease in efficiency reached a steady state. The results indicated that impairment of efficiency apparently occurred at a level of 85 dBA and that the interference effect of noise was more pronounced on task performance with mental strain.

  3. The role of each compartment in a two-compartment vertical flow reactor for ferruginous mine water treatment. (United States)

    Yim, G J; Cheong, Y W; Hong, J H; Hur, W


    A vertical flow reactor (VFR) has been suggested for remediation of ferruginous mine drainage that passes down through an accreting bed of ochre. However, a VFR has a limited operation time until the system begins to overflow. In this study, a mathematical model was developed as a part of the effort to explore the operation of a VFR, showing dynamic changes in the head differences, ochre depths, and Fe(II)/Fe(III) concentrations in the effluent flow. The analysis showed that VFR operation time extended from 148.5 days to 163 days in an equally divided and to 168.4 days in asymmetrically (0.72:0.28) divided two-compartment VFR, suggesting that an optimum compartment ratio exists that maximizes the VFR operation time. A constant head filtration in the first compartment maximized filtration efficiency and thus prolonged VFR longevity in the two-compartment VFR. Fe(II) oxidation and ochre formation should be balanced with the permeability of the ochre bed to maximize the VFR operation time and minimize the residual Fe(II) in the effluent. Accelerated Fe(II) oxidation affected the optimum ratio of the compartment area and reduced the residual Fe(II) in the effluent. The VFR operation time can be prolonged significantly from 764 days to 3620 days by increasing the rate of ochre formation, much more than by accelerating the Fe(II) oxidation. During the prolonged VFR operation, ochre formed largely in the first compartment, while overflowing mine water with reduced iron content was effectively filtered in the second compartment. These results not only provide a better understanding of VFR operation but also suggest the direction of evolution of two-compartment VFR toward a compact and highly efficient facility integrated with an aerated cascade and with automatic coagulant feeding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Organic nano-compartments as biomimetic reactors, and protocells

    DEFF Research Database (Denmark)

    Monnard, Pierre-Alain; Ziock, Hans-Joachim; DeClue, Michael S.


    In recent years, nanoscale self-assembled structures have attracted ever increasing attention because of their potential to act as molecular templates for the synthesis of novel materials, delivery vehicles for therapeutic agents, and compartments defined at the molecular level that provide envir...


    DEFF Research Database (Denmark)

    Binder, Janos X; Pletscher-Frankild, Sune; Tsafou, Kalliopi


    of the localization of a protein, it is thus necessary to consult multiple databases and prediction tools. To address this, we present the COMPARTMENTS resource, which integrates all sources listed above as well as the results of automatic text mining. The resource is automatically kept up to date with source...

  6. The near boiling reactor: Conceptual design of a small inherently safe nuclear reactor to extend the operational capability of the Victoria Class submarine (United States)

    Cole, Christopher J. P.

    Nuclear power has several unique advantages over other air independent energy sources for nuclear combat submarines. An inherently safe, small nuclear reactor, capable of supply the hotel load of the Victoria Class submarines, has been conceptually developed. The reactor is designed to complement the existing diesel electric power generation plant presently onboard the submarine. The reactor, rated at greater than 1 MW thermal, will supply electricity to the submarine's batteries through an organic Rankine cycle energy conversion plant at 200 kW. This load will increase the operational envelope of the submarine by providing up to 28 continuous days submerged, allowing for an enhanced indiscretion ratio (ratio of time spent on the surface versus time submerged) and a limited under ice capability. The power plant can be fitted into the existing submarine by inserting a 6 m hull plug. With its simplistic design and inherent safety features, the reactor plant will require a minimal addition to the crew. The reactor employs TRISO fuel particles for increased safety. The light water coolant remains at atmospheric pressure, exiting the core at 96°C. Burn-up control and limiting excess reactivity is achieved through movable reflector plates. Shut down and regulatory control is achieved through the thirteen hafnium control rods. Inherent safety is achieved through the negative prompt and delayed temperature coefficients, as well as the negative void coefficient. During a transient, the boiling of the moderator results in a sudden drop in reactivity, essentially shutting down the reactor. It is this characteristic after which the reactor has been named. The design of the reactor was achieved through modelling using computer codes such as MCNP5, WIMS-AECL, FEMLAB, and MicroShield5, in addition to specially written software for kinetics, heat transfer and fission product poisoning calculations. The work has covered a broad area of research and has highlighted additional areas


    Directory of Open Access Journals (Sweden)

    SEDIN V. L.


    Full Text Available Problem statement. Providing of safe exploitation of nuclear power plants, as well as a safety of staff and environment is a very important problem. A distinct feature of this problem is a necessity to provide not only a strength of structures, but also a safe functioning of all systems that control nuclear process. In particular, the influence of earthquake should be considered on constructions of buildings and structures of nuclear and thermal power plant, taking into account soil-structure interaction. According to IAEA’s SSD-9 recommendations, a risk of vibration of soil should be analyzed for each NPP connected with earthquakes soil that means researches, including general, detailed and microseismic zoning of the area works. One of the distinctive features of the considered problem is an evaluation of the seismicity of area and getting the response spectrum on the free surface. Purpose. Determination of seismic resistance of buildings of high category of safety with the example of the reactor compartment of Zaporoghskaya NPP including the soil structure interaction. Conclusion The seismicity assessment of the area and obtaining of response specters on free surface was made during research and analysis of seismic resistance of buildings of high category of safety including the effects of foundation and structures. The method of modeling of the equivalent dynamic characteristics of the base was considered during the research in seismic impacts.

  8. A two-compartment fluidized bed reactor for CO{sub 2} capture by chemical-looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Kronberger, B.; Loeffler, G.; Hofbauer, H. [Vienna University of Technology, Institute of Chemical Engineering, Getreidemarkt 9/1663, A-1060 Vienna (Austria); Johansson, E.; Mattisson, T.; Lyngfelt, A. [Chalmers University of Technology, Department of Energy Conversion, S-412 96 Gothenburg (Sweden)


    Chemical-looping combustion (CLC) is a combustion method for a gaseous fuel with inherent separation of the greenhouse gas carbon dioxide. A CLC system consists of two reactors, an air reactor and a fuel reactor, and an oxygen carrier circulating between the two reactors. The oxygen carrier transfers the oxygen from the air to the fuel. The flue gas from the fuel reactor consists of carbon dioxide and water, while the flue gas from the air reactor is nitrogen from the air. A two-compartment fluidized bed CLC system was designed and tested using a flow model in order to find critical design parameters. Gas velocities and slot design were varied, and the solids circulation rate and gas leakage between the reactors were measured. The solids circulation rate was found to be sufficient. The gas leakage was somewhat high but could be reduced by altering the slot design. Finally, a hot laboratory CLC system is presented with an advanced design for the slot and also with the possibility for inert gas addition into the downcomer for solids flow increase. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  9. Allothermal steam gasification of biomass in cyclic multi-compartment bubbling fluidized-bed gasifier/combustor - new reactor concept. (United States)

    Iliuta, Ion; Leclerc, Arnaud; Larachi, Faïçal


    A new reactor concept of allothermal cyclic multi-compartment fluidized bed steam biomass gasification is proposed and analyzed numerically. The concept combines space and time delocalization to approach an ideal allothermal gasifier. Thermochemical conversion of biomass in periodic time and space sequences of steam biomass gasification and char/biomass combustion is simulated in which the exothermic combustion compartments provide heat into an array of interspersed endothermic steam gasification compartments. This should enhance unit heat integration and thermal efficiency and procure N(2)-free biosyngas with recourse neither to oxygen addition in steam gasification nor contact between flue and syngas. The dynamic, one-dimensional, multi-component, non-isothermal model developed for this concept accounts for detailed solid and gas flow dynamics whereupon gasification/combustion reaction kinetics, thermal effects and freeboard-zone reactions were tied. Simulations suggest that allothermal operation could be achieved with switch periods in the range of a minute supporting practical feasibility for portable small-scale gasification units. Copyright 2009 Elsevier Ltd. All rights reserved.

  10. Submarine hydrodynamics

    CERN Document Server

    Renilson, Martin


    This book adopts a practical approach and presents recent research together with applications in real submarine design and operation. Topics covered include hydrostatics, manoeuvring, resistance and propulsion of submarines. The author briefly reviews basic concepts in ship hydrodynamics and goes on to show how they are applied to submarines, including a look at the use of physical model experiments. The issues associated with manoeuvring in both the horizontal and vertical planes are explained, and readers will discover suggested criteria for stability, along with rudder and hydroplane effectiveness. The book includes a section on appendage design which includes information on sail design, different arrangements of bow planes and alternative stern configurations. Other themes explored in this book include hydro-acoustic performance, the components of resistance and the effect of hull shape. Readers will value the author’s applied experience as well as the empirical expressions that are presented for use a...

  11. Marine dispersion of radioactive elements susceptible to be released by the reactors of the Kursk damaged nuclear submarine; Dispersion marine des elements radioactifs susceptibles d'etre liberes par les reacteurs du sous-marin nucleaire accidente Koursk

    Energy Technology Data Exchange (ETDEWEB)

    Calmet, D. [CEA/Fontenay-aux-Roses, Inst. de Protection et de Surete Nucleaire, IPSN, 92 (France); Lepicard, S. [Centre d' Etude sur l' Evaluation de la Protection dans le Domaine Nucleaire, 92 - Fontenay-aux-Roses (France)


    The Kursk nuclear submarine has been damaged on the 12. august 2000. It is on the bottom of the Barents sea. The loss of watertightness of the two nuclear reactors, that contain some hundred of kilograms of fuel (enriched uranium) would lead to the release of radioactive elements. This report specifies the general conditions of circulation of water mass susceptible to be concerned by an eventual radioactive contamination. evaluates the times of water transit that could be contaminated and then evaluates the activities contributions susceptible to be added with time to the sea waters and sea products from the French coasts of Atlantic and Channel. (N.C.)

  12. Climatic conditions inside nuclear reactor containments : Evaluation of moisture condition in the concrete within reactor containments and interaction with the ambient compartments


    OXFALL, Mikael


    Safety is the top priority at a nuclear facility. The nuclear power plants are designed to prevent radioactive leakage to the surroundings, both during normal operation as well as in case of a severe accident. One of the most important structures in a nuclear power plant, with regard to safety, is thus the reactor containment wall. The containment wall is the last main barrier to prevent radioactive leakage, and it is designed to limit and control internal hazards if all other barriers fail. ...

  13. Third party liability of nuclear installation decommissioning with Russian nuclear submarines as an example: insurance versus technologies

    Energy Technology Data Exchange (ETDEWEB)

    Gavrilov, S.D. [PREKSAT Ltd., Moscow (Russian Federation); Derevyankin, A.A. [Reseaarch and Development Institute of Nuclear Power Engineering, Moscow (Russian Federation); Khamyanov, L.P. [All-Russian Research Institute on NPP Operation, Moscow (Russian Federation); Kovalenko, V.N. [Ministry for Nuclear Energy Of Russian, Moscow (Russian Federation); Kovalivich, O.M. [Research and Technological Center for Nuclear and Radiation Safety of Supervisory, Nuclear Energy State Commitee of Russia, Moscow (Russian Federation); Smirnov, P.L. [Nuclear Safety Institute of Russian Academy of Sciences, Moscow (Russian Federation)


    Third party and environment of civil liability damage caused by incidents at military nuclear installations, for instance at decommissioned NPS (nuclear powered submarines), may be divided into three main trends: -) Liability of NPS without high-enriched irradiated nuclear fuel (SNF) for its self-submersion (radiation incident); -) Liability of NPS with SNF aboard for its self-submersion (radiation incident); and -) Liability of floating NPS for its SNF discharge (nuclear accident). Without step-by-step transition from the Russian Federation guaranties to insurance and making allowance for liability limits according to the Vienna Convention approach, the sizes of the financial guarantee for the civil liability of the NPS owner (Russian state), in US dollars of 2000, are approximately assessed as the following: -) storing decommissioned NPS or a floating module without SNF - from 12 to 25 thousand dollars per year (per one submarine or module); -) storing decommissioned NPS with SNF inside reactors cores - from 25 to 40 thousand dollars per year; -) assembly-by-assembly removing SNF from reactors' core of decommissioned NPS - up to 1.5 million dollars for undamaged reactor per the discharging period; -) SNF removing within reactor using the filled in-space reactor's core by liquid-phased hardened or dispersed solid-phase materials from decommissioned NPS - from 30 to 50 thousand dollars for undamaged reactor per the discharging period. Both rates and sums for NPS with damaged reactors are to be estimated for the each damaged reactor and NPS at all. It is necessary to perform the measures reducing the risk of nuclear accidents of NPS with undamaged SNF and NPS with damaged reactors in possibly short time. It will allow not only to cut risks by ten times and more, but also to accumulate necessary insurance reserves faster. These measures can be partially or completely executed using the preventing measures reserves assigned to all decommissioned Russian NPS

  14. Submarine Medicine Team (United States)

    Federal Laboratory Consortium — The Submarine Medicine Team conducts basic and applied research on biomedical aspects of submarine and diving environments. It focuses on ways to optimize the health...

  15. Compartment syndromes (United States)

    Mubarak, S. J.; Pedowitz, R. A.; Hargens, A. R.


    The compartment syndrome is defined as a condition in which high pressure within a closed fascial space (muscle compartment) reduces capillary blood perfusion below the level necessary for tissue viability'. This condition occurs in acute and chronic (exertional) forms, and may be secondary to a variety of causes. The end-result of an extended period of elevated intramuscular pressure may be the development of irreversible tissue injury and Volkmann's contracture. The goal of treatment of the compartment syndrome is the reduction of intracompartmental pressure thus facilitating reperfusion of ischaemic tissue and this goal may be achieved by decompressive fasciotomy. Controversy exists regarding the critical pressure-time thresholds for surgical decompression and the optimal diagnostic methods of measuring intracompartmental pressures. This paper will update and review some current knowledge regarding the pathophysiology, aetiology, diagnosis, and treatment of the acute compartment syndrome.

  16. Compartment syndromes

    Directory of Open Access Journals (Sweden)

    Aly Saber


    Full Text Available Body compartments bound by fascia and limited by bony backgrounds are found in the extremities, buttocks, abdomen and thoracic cavity; conditions that cause intracompartmental swelling and hypertension can lead to ischemia and limb loss. Although compartment syndromes are described in all body regions from head to toe, the etiology, diagnosis, treatment, and prevention are best characterized for three key body regions: the first is extremity, the second is abdominal, and the third is thoracic compartment syndromes. Thoracic compartment syndrome usually occurs as a result of pathological accumulation of air, fluid or blood in the mediastinum and has traditionally been described in trauma. As the intracranial contents are confined within a rigid bony cage, any increase in volume within this compartment as a result of brain oedema or an expanding traumatic intracranial haematoma, leads to a reciprocal decrease in the volume of cerebrospinal fluid and intracranial venous blood volume. Limb compartment syndromes may present either in acute or chronic clinical forms. Intra-abdominal pressure can be measured by direct or indirect methods. While the direct methods are quite accurate, they are impractical and not feasible for routine practice. Indirect measurement is done through inferior vena cava, gastric, rectal and urinary bladder. Indirect measurement through urinary bladder is the simplest and is considered the method of choice for intra-abdominal pressure measurement. The management of patients with intra-abdominal hypertension is based on four important principles: the first is related to the specific procedures aiming at lowering intra-abdominal pressure and the consequences of intra-abdominal hypertension and abdominal compartment syndrome; the second is for general support and medical management of the critically ill patient; while the third is surgical decompression and the fourth is optimization after surgical decompression.


    Treshow, M.


    Reactors of the boiling water type are described wherein water serves both as the moderator and coolant. The reactor system consists essentially of a horizontal pressure vessel divided into two compartments by a weir, a thermal neutronic reactor core having vertical coolant passages and designed to use water as a moderator-coolant posltioned in one compartment, means for removing live steam from the other compartment and means for conveying feed-water and water from the steam compartment to the reactor compartment. The system further includes auxiliary apparatus to utilize the steam for driving a turbine and returning the condensate to the feed-water inlet of the reactor. The entire system is designed so that the reactor is self-regulating and has self-limiting power and self-limiting pressure features.

  18. Navy Virginia (SSN-774) Class Attack Submarine Procurement: Background and Issues for Congress (United States)


    reactors or non- nuclear power sources such as diesel engines or fuel cells. All U.S. Navy submarines are nuclear - powered. A submarine’s use of...the Navy’s plan to design and procure a next - generation ballistic missile submarine called the Ohio Replacement Program or SSBN(X). 26...the next several years require these submarines to use up their nuclear fuel cores more quickly than the Navy now projects, then the amounts of time

  19. Navy Virginia (SSN 774) Class Attack Submarine Procurement: Background and Issues for Congress (United States)


    powered attack submarines (SSNs). The SSNs are general -purpose submarines that can (when appropriately equipped and armed) perform a variety of...signs of tampering. The defective elbow pipe, used to funnel steam from the reactor to the sub’s propulsion turbines and generators , showed evidence of...Congressional Research Service Summary The Navy has been procuring Virginia (SSN-774) class nuclear- powered attack submarines since FY1998. The two Virginia

  20. Low cost submarine robot


    Ponlachart Chotikarn; Werapong Koedsin; Boonlua Phongdara; Pattara Aiyarak


    A submarine robot is a semi-autonomous submarine robot used mainly for marine environmental research. We aim todevelop a low cost, semi-autonomous submarine robot which is able to travel underwater. The robot’s structure was designedand patented using a novel idea of the diving system employing a volume adjustment mechanism to vary the robot’s density.A light weight, flexibility and small structure provided by PVC can be used to construct the torpedo-liked shape robot.Hydraulic seal and O-rin...

  1. Low cost submarine robot

    Directory of Open Access Journals (Sweden)

    Ponlachart Chotikarn


    Full Text Available A submarine robot is a semi-autonomous submarine robot used mainly for marine environmental research. We aim todevelop a low cost, semi-autonomous submarine robot which is able to travel underwater. The robot’s structure was designedand patented using a novel idea of the diving system employing a volume adjustment mechanism to vary the robot’s density.A light weight, flexibility and small structure provided by PVC can be used to construct the torpedo-liked shape robot.Hydraulic seal and O-ring rubbers are used to prevent water leaking. This robot is controlled by a wired communicationsystem.

  2. Monitoring of the nuclear submarine Komsomolets

    Energy Technology Data Exchange (ETDEWEB)

    Heldal, Hilde E.; Flo, Janita K.; Liebig, Penny L. [Institute of Marine Research, P. O. Box 1870 Nordnes, N-5817 Bergen (Norway); Gaefvert, Torbjoern; Rudjord, Anne Liv [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Oesteraas (Norway); Gwynn, Justin P. [Norwegian Radiation Protection Authority, The Fram Centre, N-9296 Tromsoe (Norway)


    The Soviet nuclear submarine Komsomolets sank on the 7 April 1989, 180 km southwest of Bear Island in the Norwegian Sea to a depth of about 1655 m. The submarine contains one nuclear reactor containing long-lived radionuclides such as cesium-137 ({sup 137}Cs) along with other fission and activation products, in addition to 2 mixed uranium/plutonium nuclear warheads containing weapons grade plutonium. Although several model studies have shown that a radioactive leakage from Komsomolets will have insignificant impact on fish and other marine organisms, there are still public concerns about the condition of the submarine and the potential for radioactive leakage. In order to document the contamination levels and to meet public concerns, monitoring of radioactive contamination in the area adjacent to the submarine has been ongoing since 1993. Samples of bottom seawater and sediments have been collected annually by the Institute of Marine Research (IMR) and have been analysed for {sup 137}Cs and plutonium-239,240 ({sup 239,240}Pu). So far, activity concentrations in the samples have been comparable to levels found in other samples from the Norwegian and Barents Seas. During sampling from R/V 'G. O. Sars' in April 2013, an area of about 1 km{sup 2} of the seabed around Komsomolets was mapped to precisely locate the submarine using a Kongsberg EM302 multibeam echo sounder, a Simrad EK60 single beam echo sounder and an Olex 3D bottom-mapping system. For sediment sampling, a Simrad MST342 mini-transponder was attached to a Smoegen box corer to allow for precise positioning of the corer. With the aid of the Kongsberg HiPAP (High Precision Acoustic Positioning) system, 4 box cores were collected around the submarine at a distance of 10 to 20 m. In addition, one box core was collected from a reference station about 100 m upstream of the submarine. Surface sediments and sediment cores were collected from the box cores taken at each sampling location. Sediment cores

  3. Submarine Salt Karst Terrains

    Directory of Open Access Journals (Sweden)

    Nico Augustin


    Full Text Available Karst terrains that develop in bodies of rock salt (taken as mainly of halite, NaCl are special not only for developing in one of the most soluble of all rocks, but also for developing in one of the weakest rocks. Salt is so weak that many surface-piercing salt diapirs extrude slow fountains of salt that that gravity spread downslope over deserts on land and over sea floors. Salt fountains in the deserts of Iran are usually so dry that they flow at only a few cm/yr but the few rain storms a decade so soak and weaken them that they surge at dm/day for a few days. We illustrate the only case where the rates at which different parts of one of the many tens of subaerial salt karst terrains in Iran flows downslope constrains the rates at which its subaerial salt karst terrains form. Normal seawater is only 10% saturated in NaCl. It should therefore be sufficiently aggressive to erode karst terrains into exposures of salt on the thousands of known submarine salt extrusions that have flowed or are still flowing over the floors of hundreds of submarine basins worldwide. However, we know of no attempt to constrain the processes that form submarine salt karst terrains on any of these of submarine salt extrusions. As on land, many potential submarine karst terrains are cloaked by clastic and pelagic sediments that are often hundreds of m thick. Nevertheless, detailed geophysical and bathymetric surveys have already mapped likely submarine salt karst terrains in at least the Gulf of Mexico, and the Red Sea. New images of these two areas are offered as clear evidence of submarine salt dissolution due to sinking or rising aggressive fluids. We suggest that repeated 3D surveys of distinctive features (± fixed seismic reflectors of such terrains could measure any downslope salt flow and thus offer an exceptional opportunity to constrain the rates at which submarine salt karst terrains develop. Such rates are of interest to all salt tectonicians and the many

  4. Nuclear-powered submarine accidents; Les accidents de sous-marins nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Tournyol du Clos, A.


    Most of nuclear-powered ships are military ships and submarines represent 95% of the total. Most of the propulsion reactors used are of PWR type. This paper gives the principal technical characteristics of PWR ship propulsion reactors and the differences with their civil homologues. The principal accidents that occurred on US and Russian nuclear-powered submarines are also listed and the possible effects of a shipwreck on the reactor behaviour are evaluated with their environmental impact. (J.S.). 1 tab., 1 photo.

  5. Compartment Syndrome in Children. (United States)

    Hosseinzadeh, Pooya; Hayes, Christopher B


    Compartment syndrome in children can present differently than adults. Increased analgesic need should be considered the first sign of evolving compartment syndrome in children. Children with supracondylar humerus fractures, floating elbow injuries, operatively treated forearm fractures, and tibia fractures are at high risk for developing compartment syndrome. Elbow flexion beyond 90° in supracondylar humerus fractures and closed treatment of forearm fractures in floating elbow injuries are associated with increased risk of compartment syndrome. Prompt diagnosis and treatment with fasciotomy in children result in excellent long-term outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.


    African Journals Online (AJOL)

    student's MNEMONIC 5ps of ACS). The clinical diagnosis can be confirmed by compartment pressure measurements (2,6,7) and the treatment is urgent decompression by fasciotomy. Patients with compartment syndrome should be treated with utmost urgency, constant monitoring, and early decompression with appropriate ...

  7. brain compartment syndrome

    African Journals Online (AJOL)

    Compartment syndrome of the limbs or the abdomen is a well-known entity in general surgical and orthopaedic practice, characterised by an increase of pressure within a musculofascial compartment leading to progressive neurovascular dysfunction. Although it has not been described as such, raised pressure within the ...

  8. SCICEX: Submarine Arctic Science Program (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Submarine Arctic Science Program, SCICEX, is a federal interagency collaboration among the operational Navy, research agencies, and the marine research community...

  9. The Submarine, 1776-1918

    National Research Council Canada - National Science Library

    Uhlig, Frank


    When, on 11 April 1900, the U.S. Navy thought the Holland, named for its designer, that little submarine joined a fleet consisting of two armored cruisers, six monitors, seven first and second-class battleships, and seventeen each...

  10. DNA Virus Replication Compartments (United States)

    Schmid, Melanie; Speiseder, Thomas; Dobner, Thomas


    Viruses employ a variety of strategies to usurp and control cellular activities through the orchestrated recruitment of macromolecules to specific cytoplasmic or nuclear compartments. Formation of such specialized virus-induced cellular microenvironments, which have been termed viroplasms, virus factories, or virus replication centers, complexes, or compartments, depends on molecular interactions between viral and cellular factors that participate in viral genome expression and replication and are in some cases associated with sites of virion assembly. These virus-induced compartments function not only to recruit and concentrate factors required for essential steps of the viral replication cycle but also to control the cellular mechanisms of antiviral defense. In this review, we summarize characteristic features of viral replication compartments from different virus families and discuss similarities in the viral and cellular activities that are associated with their assembly and the functions they facilitate for viral replication. PMID:24257611

  11. Chronic Exertional Compartment Syndrome. (United States)

    Braver, Richard T


    Increased tissue pressure within a fascial compartment may be the result from any increase in volume within its contents, or any decrease in size of the fascial covering or its distensibility. This may lead to symptoms of leg tightness, pain or numbness brought about by exercise. There are multiple differential diagnoses of exercise induced leg pain and the proper diagnoses of chronic exertional compartment syndrome (CECS) is made by a careful history and by exclusion of other maladies and confirmed by compartment syndrome testing as detailed in this text. Surgical fasciotomies for the anterior, lateral, superficial and deep posterior compartments are described in detail along with ancillary procedures for chronic shin splints that should allow the athlete to return to competitive activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Pınar Zeyneloğlu


    Full Text Available Intraabdominal hypertension and Abdominal compartment syndrome are causes of morbidity and mortality in critical care patients. Timely diagnosis and treatment may improve organ functions. Intra-abdominal pressure monitoring is vital during evaluation of the patients and in the management algorithms. The incidence, definition and risk factors, clinical presentation, diagnosis and management of intraabdominal hypertension and Abdominal compartment syndrome were reviewed here.

  13. Submarine Information Organization and Prioritization and Submarine Officer of the Deck Experience (United States)


    The Submarine Review, 58-64. Shobe, K. (2002, May). Information organization and modeling of the submarine officer of the deck and sonar operator...Technical Report 01Oct00 - 31Sep02 SUBMARINE INFORMATION ORGANIZATION AND PRIORITIZATION AND SUBMARINE OFFICER OF THE DECK EXPERIENCE 51001 1) Katharine K

  14. Enhancing Submarine Operational Relevance: A Leadership Challenge

    National Research Council Canada - National Science Library

    Daigle, Jr, Michael J


    .... This vision of submarine operations must change. As the military continues to shift to operations focused on joint capabilities, the submarine force must break from the closed, protective, and risk averse culture of its past and push forward...

  15. Submarine silicic volcanism: Processes and products

    Digital Repository Service at National Institute of Oceanography (India)

    Kalangutkar, N.G.; Iyer, S.D.

    The occurrence of submarine silicic volcanics is rare at the mid-oceanic ridges, abyssal depths, seamounts and fracture zones. Hydrothermal processes are active in submarine silicic environments and are associated with host ores of Cu, Au, Ag, Pb...

  16. Acute compartment syndrome. (United States)

    Via, Alessio Giai; Oliva, Francesco; Spoliti, Marco; Maffulli, Nicola


    acute compartment syndrome (ACS) is one of the few true emergencies in orthopedics and traumatology. It is a painful condition caused by the increase interstitial pressure (intracompart-mental pressure - ICP) within a closed osteofascial compartment which impair local circulation. It occurs most often in the legs, but it can affects also the arms, hands, feet, and buttocks. It usually develops after a severe injury such as fractures or crush injury, but it can also occurs after a relatively minor injury and it may be iatrogenic. Uncommon causes of ACS have been also described, that suggest surgeons to pay great attention to this serious complication. Diagnosing ACS is difficult in clinical practice, even among expert surgeons. Currently, the diagnosis is made on the basis of physical examination and repeated ICP measures. ICP higher than 30 mmHg of diastolic blood pressure is significant of compartment syndrome. Once diagnosis is made, fasciotomy to release the affected compartment should be performed as early as possible because delayed decompression would lead to irreversible ischemic damage to muscles and peripheral nerves. acute compartment syndrome is a surgical emergency. There is still little consensus among authors about diagnosis and treatment of these serious condition, in particular about the ICP at which fasciotomy is absolutely indicated and the timing of wound closure. New investigations are needed in order to improve diagnosis and treatment of ACS.

  17. Acute compartment syndrome (United States)

    Via, Alessio Giai; Oliva, Francesco; Spoliti, Marco; Maffulli, Nicola


    Summary Background: acute compartment syndrome (ACS) is one of the few true emergencies in orthopedics and traumatology. It is a painful condition caused by the increase interstitial pressure (intracompart-mental pressure – ICP) within a closed osteofascial compartment which impair local circulation. It occurs most often in the legs, but it can affects also the arms, hands, feet, and buttocks. It usually develops after a severe injury such as fractures or crush injury, but it can also occurs after a relatively minor injury and it may be iatrogenic. Uncommon causes of ACS have been also described, that suggest surgeons to pay great attention to this serious complication. Diagnosing ACS is difficult in clinical practice, even among expert surgeons. Currently, the diagnosis is made on the basis of physical examination and repeated ICP measures. ICP higher than 30 mmHg of diastolic blood pressure is significant of compartment syndrome. Once diagnosis is made, fasciotomy to release the affected compartment should be performed as early as possible because delayed decompression would lead to irreversible ischemic damage to muscles and peripheral nerves. Conclusion: acute compartment syndrome is a surgical emergency. There is still little consensus among authors about diagnosis and treatment of these serious condition, in particular about the ICP at which fasciotomy is absolutely indicated and the timing of wound closure. New investigations are needed in order to improve diagnosis and treatment of ACS. PMID:25878982

  18. Air blast injuries killed the crew of the submarine H.L. Hunley.

    Directory of Open Access Journals (Sweden)

    Rachel M Lance

    Full Text Available The submarine H.L. Hunley was the first submarine to sink an enemy ship during combat; however, the cause of its sinking has been a mystery for over 150 years. The Hunley set off a 61.2 kg (135 lb black powder torpedo at a distance less than 5 m (16 ft off its bow. Scaled experiments were performed that measured black powder and shock tube explosions underwater and propagation of blasts through a model ship hull. This propagation data was used in combination with archival experimental data to evaluate the risk to the crew from their own torpedo. The blast produced likely caused flexion of the ship hull to transmit the blast wave; the secondary wave transmitted inside the crew compartment was of sufficient magnitude that the calculated chances of survival were less than 16% for each crew member. The submarine drifted to its resting place after the crew died of air blast trauma within the hull.

  19. Spontaneous Thigh Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Khan, Sameer K


    Full Text Available A young man presented with a painful and swollen thigh, without any history of trauma, illness, coagulopathic medication or recent exertional exercise. Preliminary imaging delineated a haematoma in the anterior thigh, without any fractures or muscle trauma. Emergent fasciotomies were performed. No pathology could be identified intra-operatively, or on follow-up imaging. A review of thigh compartment syndromes described in literature is presented in a table. Emergency physicians and traumatologists should be cognisant of spontaneous atraumatic presentations of thigh compartment syndrome, to ensure prompt referral and definitive management of this limb-threatening condition. [West J Emerg Med. 2011;12(1:134-138].

  20. North American Submarine Cable Association (NASCA) Submarine Cables (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data show the locations of in-service and out-of-service submarine cables that are owned by members of NASCA and located in U.S. territorial waters. More...

  1. Rotary reactor and use thereof

    NARCIS (Netherlands)

    Bakker Wridzer, J.W.; Kapteijn, F.; Moulijn, J.A.


    The invention relates to a rotary reactor consisting of a number of tubular reaction compartments (A), each provided with a first end and a second end, a ceramic first reactor end plate (B) in which said first ends are received, and a second end plate (B) in which said second ends are received,

  2. Submarine geothermal resources (United States)

    Williams, D.L.


    Approximately 20% of the earth's heat loss (or 2 ?? 1012 cal/s) is released through 1% of the earth's surface area and takes the form of hydrothermal discharge from young (Pleistocene or younger) rocks adjacent to active seafloor-spreading centers and submarine volcanic areas. This amount is roughly equivalent to man's present gross energy consumption rate. A sub-seafloor geothermal reservoir, to be exploitable under future economic conditions, will have to be hot, porous, permeable, large, shallow, and near an energy-deficient, populated land mass. Furthermore, the energy must be recoverable using technology achievable at a competitive cost and numerous environmental, legal and institutional problems will have to be overcome. The highest-temperature reservoirs should be found adjacent to the zones of the seafloor extension or volcanism that are subject to high sedimentation rates. The relatively impermeable sediments reduce hydrothermal-discharge flow rates, forcing the heat to be either conducted away or released by high-temperature fluids, both of which lead to reservoir temperatures that can exceed 300??C. There is evidence that the oceanic crust is quite permeable and porous and that it was amenable to deep (3-5 km) penetration by seawater at least some time in the early stages of its evolution. Most of the heat escapes far from land, but there are notable exceptions. For example, in parts of the Gulf of California, thermal gradients in the bottom sediments exceed 1??C/m. In the coastal areas of the Gulf of California, where electricity and fresh water are at a premium, this potential resource lies in shallow water (< 200 m) and within sight of land. Other interesting areas include the Sea of Japan, the Sea of Okhotsk and the Andaman Sea along the margins of the western Pacific, the Tyrrhenian Sea west of Italy, and the southern California borderland and west flank of the Juan de Fuca Ridge off the west coast of the United States. Many questions remain to be

  3. Submarine canyons off Madras Coast

    Digital Repository Service at National Institute of Oceanography (India)

    Setty, M.G.A.P.

    Submarine canyons off the coast of Madras, Tamil Nadu, India were studied during cruise of @iINS Kistna@@ as part of the IIOE programme They consist of hill-like projections and V-shaped valleys Their other features are also reported...

  4. Neonatal compartment syndrome. (United States)

    Martin, B; Treharne, L


    A term neonate was born with a grossly swollen and discoloured left hand and forearm. He was transferred from the local hospital to the plastic surgical unit, where a diagnosis of compartment syndrome was made and he underwent emergency forearm fasciotomies at six hours of age. Following serial debridements of necrotic tissue, he underwent split-thickness skin grafting of the resultant defects of his forearm, hand and digits. At the clinic follow-up appointment two months after the procedure, he was found to have developed severe flexion contractures despite regular outpatient hand therapy and splintage. He has had further reconstruction with contracture release, use of artificial dermal matrix, and K-wire fixation of the thumb and wrist. Despite this, the long term outcome is likely to be an arm with poor function. The key learning point from this case is that despite prompt transfer, diagnosis and appropriate surgical management, the outcome for neonatal compartment syndrome may still be poor.

  5. Disposal of Russian nuclear submarines and surface ships; Deutsch-russisches Gemeinschaftsprojekt zur Entsorgung russischer Atom-U-Boote

    Energy Technology Data Exchange (ETDEWEB)

    Klammt, Jens-Uwe; Menger, Bernd; Mietann, Detlef [Energiewerke Nord GmbH, Rubenow (Germany)


    A German contribution to the initiative of the Global G8 Partnership against the Proliferation of Weapons of Mass Destruction is a project for the disposal of decommissioned nuclear submarines of the Russian Northern Sea Fleet. The Federal Republic of Germany makes available a total of 600 million euro for this purpose for the period of 2003 to 2014. Since 2003, a long-term store has been under construction in the Saida Bay in the Murmansk region for land-based storage of mothballed reactor sections from decommissioned nuclear submarines and components of nuclear surface ships with a total of 178 storage positions, the necessary infrastructure included. At the present time, 33 mothballed reactor sections of disassembled nuclear submarines are stored there. Work is also under way to build and equip a center for conditioning, treatment, and long-term storage of radioactive waste from the northwestern region of Russia, which will be commissioned in 2014. This waste management center is a key item in Russian plans for the establishment of radiologically safe conditions in the region. Germany financed the disassembly of 20 submarines into reactor sections fit for storage. Extensive assistance was provided in improving the material technical basis of the shipyard commissioned to dispose of the nuclear submarines. (orig.)

  6. SCICEX: Submarine Arctic Science Program, Version 1 (United States)

    National Aeronautics and Space Administration — The Submarine Arctic Science Program, SCICEX, is a federal interagency collaboration among the operational Navy, research agencies, and the marine research community...

  7. Anterior vaginal compartment surgery. (United States)

    Maher, Christopher


    To review the safety and efficacy of anterior vaginal compartment pelvic organ prolapse surgery. Every 4 years and as part of the Fifth International Collaboration on Incontinence we reviewed the English-language scientific literature after searching PubMed, Medline, Cochrane library and the Cochrane database of systematic reviews, published up to January 2012. Publications were classified as level 1 evidence (randomised controlled trials [RCT] or systematic reviews), level 2 (poor quality RCT, prospective cohort studies), level 3 (case series or retrospective studies) and level 4 case reports. The highest level of evidence was utilised by the committee to make evidence-based recommendations based upon the Oxford grading system. A grade A recommendation usually depends on consistent level 1 evidence. A grade B recommendation usually depends on consistent level 2 and/or 3 studies, or "majority evidence" from RCTs. A grade C recommendation usually depends on level studies or "majority evidence" from level 2/3 studies or Delphi processed expert opinion. A grade D "no recommendation possible" would be used where the evidence is inadequate or conflicting and when expert opinion is delivered without a formal analytical process, such as by Delphi. Absorbable mesh augmentation of anterior compartment native tissue repair improves the anatomical outcome compared with native tissue repair alone with no increased complication rate in meta-analysis of 2 RCTS (grade B). Biological grafts in meta-analysis have improved anatomical outcomes with no change in subjective outcomes compared with native tissue repairs (grade B). There is conflicting level 1 evidence to support porcine dermis and a single RCT to support small intestine submucosa as graft agents in anterior compartment prolapse surgery (grade B). Consistent level 1 data support a superior anatomical outcome for polypropylene mesh compared with a biological graft in the anterior compartment. Mesh exposure rate was

  8. Compartment syndrome without pain!

    LENUS (Irish Health Repository)

    O'Sullivan, M J


    We report the case of a young male patient who underwent intra-medullary nailing for a closed, displaced mid-shaft fracture of tibia and fibula. He was commenced on patient controlled analgesia post-operatively. A diagnosis of compartment syndrome in the patient\\'s leg was delayed because he did not exhibit a pain response. This ultimately resulted in a below-knee amputation of the patient\\'s leg. We caution against the use of patient controlled analgesia in any traumatised limb distal to the hip or the shoulder.

  9. Submarines, spacecraft and exhaled breath. (United States)

    Pleil, Joachim D; Hansel, Armin


    Foreword The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of artificial atmospheres practised by the submarine air monitoring and air purification (SAMAP) community. SAMAP is comprised of manufacturers, researchers and medical professionals dealing with the engineering and instrumentation to support human life in submarines and spacecraft (including shuttlecraft and manned rockets, high-altitude aircraft, and the International Space Station (ISS)). Here, the immediate concerns are short-term survival and long-term health in fairly confined environments where one cannot simply 'open the window' for fresh air. As such, one of the main concerns is air monitoring and the main sources of contamination are CO(2) and other constituents of human exhaled breath. Since the inaugural meeting in 1994 in Adelaide, Australia, SAMAP meetings have been held every two or three years alternating between the North American and European continents. The meetings are organized by Dr Wally Mazurek (a member of IABR) of the Defense Systems Technology Organization (DSTO) of Australia, and individual meetings are co-hosted by the navies of the countries in which they are held. An overriding focus at SAMAP is life support (oxygen availability and carbon dioxide removal). Certainly, other air constituents are also important; for example, the closed environment of a submarine or the ISS can build up contaminants from consumer products, cooking, refrigeration, accidental fires, propulsion and atmosphere maintenance. However, the most immediate concern is sustaining human metabolism: removing exhaled CO(2) and replacing metabolized O(2). Another

  10. Numerical Study on Hydrogen Flow Behavior in Two Compartments with Different Connecting Pipes

    Directory of Open Access Journals (Sweden)

    HanChen Liu


    Full Text Available Hydrogen accumulation in the containment compartments under severe accidents would result in high concentration, which could lead to hydrogen deflagration or detonation. Therefore, getting detailed hydrogen flow and distribution is a key issue to arrange hydrogen removal equipment in the containment compartments. In this study, hydrogen flow behavior in local compartments has been investigated in two horizontal compartments. The analysis model is built by 3-dimensional CFD code in Cartesian coordinates based on the connection structure of the Advanced Pressurized Water Reactor (PWR compartments. It consists of two cylindrical vessels, representing the Steam Generator compartment (SG and Core Makeup Tank compartment (CMT. With standard k-ε turbulence model, the effects of the connecting pipe size and location on hydrogen concentration distribution are investigated. Results show that increasing the diameter of connection pipe (IP which is located at 800 mm from 150 mm to 300 mm facilitates hydrogen flow between compartments. Decreasing the length of IP which is located at 800 mm from 1000 mm to 500 mm can also facilitate hydrogen flow between compartments. Lower IP is in favor of hydrogen mixing with air in non-source compartment. Higher IP is helpful for hydrogen flow to the non-source term compartment from source term compartment.

  11. Modular Lead-Bismuth Fast Reactors in Nuclear Power


    Georgy Toshinsky; Vladimir Petrochenko


    On the basis of the unique experience of operating reactors with heavy liquid metal coolant–eutectic lead-bismuth alloy in nuclear submarines, the concept of modular small fast reactors SVBR-100 for civilian nuclear power has been developed and validated. The features of this innovative technology are as follows: a monoblock (integral) design of the reactor with fast neutron spectrum, which can operate using different types of fuel in various fuel cycles including MOX fuel in a self-providing...

  12. Submarine landslides: advances and challenges (United States)

    Locat, Jacques; Lee, Homa J.


    Due to the recent development of well-integrated surveying techniques of the sea floor, significant improvements were achieved in mapping and describing the morphology and architecture of submarine mass movements. Except for the occurrence of turbidity currents, the aquatic environment (marine and fresh water) experiences the same type of mass failure as that found on land. Submarine mass movements, however, can have run-out distances in excess of 100 km, so their impact on any offshore activity needs to be integrated over a wide area. This great mobility of submarinemass movements is still not very well understood, particularly for cases like the far-reaching debris flows mapped on the Mississippi Fan and the large submarine rock avalanches found around many volcanic islands. A major challenge ahead is the integration of mass movement mechanics in an appropriate evaluation of the hazard so that proper risk assessment methodologies can be developed and implemented for various human activities offshore, including the development of natural resources and the establishment of reliable communication corridors. Key words : submarine slides, hazards, risk assessment, morphology, mobility, tsunami. Le dveloppement rcent de techniques de levs hydrograhiques pour les fonds marins nous a permis d'atteindre une qualit ingale dans la cartographie et la description des glissements sous marins. l'exception des courants de turbidit, on retrouve dans le domaine aquatique les mmes types de mouvements de terrain que sur terre. Par contre, les glissements sous-marins peuvent atteindre des distances excdant 100 km de telle sorte que leur impact sur les activits offshore doit tre pris en compte sur degrandes tendues. La grande mobilit des glissements sous-marins n'est pas encore bien comprise, comme pour le cas des coules dedbris cartographies sur le cne du Mississippi ainsi que pour les grandes avalanches rocheuses sous-marines retrouves au pourtour des les volcaniques. Un dfi majeur

  13. Health and environmental risk assessment associated with a potential recovery of the Russian submarine K-27

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, A.; Amundsen, I.; Brown, J.E.; Dowdall, M.; Standring, W. [Norwegian Radiation Protection Authority/CERAD CoE (Norway); Bartnicki, J. [Norwegian Meteorological Institute/CERAD CoE (Norway); Karcher, M. [O.A.Sys - Ocean Atmosphere Systems GmbH (Germany); Lind, O.C.; Salbu, B. [Norwegian University of Life Sciences/CERAD CoE (Norway)


    The nuclear submarine K-27 is one of several objects with spent nuclear fuel (SNF) which has been dumped in the Arctic. It contained two liquid metal reactors (LMRs) of 70 MW maximum thermal power each and used Pb-Bi as the coolant. The reactors were loaded with 180 kg of U-235 at an enrichment of 90 %. In September 1981, the submarine was sunk in the shallow waters of Stepovoy Fjord at an estimated depth of 30 m. Concerns have been expressed by various parties regarding the issue of dumped nuclear waste in the Kara Sea and in particular the submarine K-27. To address these concerns and to provide a better basis for evaluating possible radiological impact (especially as a consequence of a potential recovery of the submarine), an environmental impact assessment has been undertaken. The study is based on construction of different hypothetical accident scenarios and evaluating possible associated consequences for human and the environment. In general, three main scenarios seem probable and thus appropriate for consideration. One is the 'zero- alternative', i.e. investigate the current and future impact assuming no interventions. The second considers an accidental scenario involving the raising of the submarine and the third an accidental scenario related to the transportation of the submarine to shore for defueling. With regards to the accidental scenarios related to raising and transportation of the submarine, two alternatives can be considered depending on where and how a hypothetical accident will take place and whether the subsequent releases occur under water or at the water surface. The issue of an uncontrolled chain reaction occurring as a result of a potential recovery of the submarine will be included in the assessment. The work includes application of state of the art 3D hydrodynamic and atmospheric dispersion models to investigate the transport, distribution and fate of relevant radionuclides following a hypothetical accident in aquatic and

  14. Compartment Syndrome of the Hand. (United States)

    Oak, Nikhil R; Abrams, Reid A


    Hand compartment syndrome has many etiologies; untreated, it has dire functional consequences. Intracompartmental pressure exceeding capillary filling pressure causes decreased tissue perfusion resulting in progressive ischemic death of compartment contents. Clinical findings can evolve. Serial physical examinations are recommended and, if equivocal, interstitial pressure monitoring is indicated. Definitive management is emergent fasciotomies with incisions designed to decompress the involved hand compartments, which could include the thenar, hypothenar, and interosseous compartments, and the carpal tunnel. Careful wound care, edema management, splinting, and hand therapy are critical. Therapy should start early postoperatively, possibly before wound closure. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Similarities between rivers and submarine channels (United States)

    Balcerak, Ernie


    Scientists have long known that the width and depth of rivers follows a power law relationship with discharge. They have also noticed that submarine channels appear to be similar to terrestrial rivers, but there have not been many systematic comparisons of the relationships between submarine channel morphology and discharge. Konsoer et al. compared the width, depth, and slope of 177 submarine channels to those of 231 river cross sections. They found that submarine channels are up to an order of magnitude wider and deeper than the largest terrestrial rivers, but they exhibit a similar power law relationship between width and depth. For submarine channels that were similar in size to rivers, the authors found that submarine channels tend to be 1 to 2 orders of magnitude steeper than rivers. The authors also inferred values for sediment concentration in the turbidity currents in the channels and combined this with estimated mean flow velocities to look for a relationship between discharge and morphology in the channels. They found that like rivers, the width and depth of the submarine channels follow a power law scaling with discharge. (Journal of Geophysical Research-Earth Surface, doi:10.1029/2012JF002422, 2013)

  16. Calciclastic submarine fans: An integrated overview (United States)

    Payros, Aitor; Pujalte, Victoriano


    Calciclastic submarine fans are rare in the stratigraphic record and no bona fide present-day analogue has been described to date. Possibly because of that, and although calciclastic submarine fans have long intrigued deep-water carbonate sedimentologists, they have largely been overlooked by the academic and industrial communities. To fill this gap we have compiled and critically reviewed the existing sedimentological literature on calciclastic submarine fans, thus offering an updated view of this type of carbonate slope sedimentary system. Calciclastic submarine fans range in length from just a few to more than 100 km. Three different types can be distinguished: (1) Coarse-grained, small-sized (depression associated with tectonic structures, an inherited topography, or large-scale mass failures.

  17. Aspects of Propeller Developements for a Submarine

    DEFF Research Database (Denmark)

    Andersen, Poul; kappel, Jens Julius; Spangenberg, Eugen


    Design and development of propellers for submarines are in some ways different from propellers for surface vessels. The most important demand is low acoustic signature that has priority over propeller efficiency, and the submarine propeller must be optimized with respect to acoustics rather than...... efficiency. Moreover the operating conditions of a submarine propeller are quite different. These aspects are discussed as well as the weighing of the various propeller parameters against the design objectives. The noise generated by the propeller can be characterized as thrust noise due to the inhomogeneous...... wake field of the submarine, trailing-edge noise and noise caused by turbulence in the inflow. The items discussed are demonstrated in a case study where a propeller of the Kappel type was developed. Three stages of the development are presented, including a design of an 8-bladed propeller where...

  18. Russia's Submarine Force: Determinants and Prospects

    National Research Council Canada - National Science Library

    Tully, John


    ... the determinants of these events, The Russian Federation inherited a huge submarine fleet from the Soviet Union, Due to the changing conditions in the world and in Russia, its future status is in doubt...

  19. SSN 774 Virginia Class Submarine (SSN 774) (United States)


    Report: The VIRGINIA Class Submarine Program continues to deliver submarines within cost, ahead of schedule , with improved quality and with...baseline schedule threshold set ten years earlier, in 1994. June 20, 2006: USS TEXAS, which was essentially the second lead ship of the class , is the first...factored for the VIRGINIA Class based on weight. Public and private shipyard data was used, as well as the maintenance schedule provided in the CARD, Rev E

  20. Submarine landslides: processes, triggers and hazard prediction. (United States)

    Masson, D G; Harbitz, C B; Wynn, R B; Pedersen, G; Løvholt, F


    Huge landslides, mobilizing hundreds to thousands of km(3) of sediment and rock are ubiquitous in submarine settings ranging from the steepest volcanic island slopes to the gentlest muddy slopes of submarine deltas. Here, we summarize current knowledge of such landslides and the problems of assessing their hazard potential. The major hazards related to submarine landslides include destruction of seabed infrastructure, collapse of coastal areas into the sea and landslide-generated tsunamis. Most submarine slopes are inherently stable. Elevated pore pressures (leading to decreased frictional resistance to sliding) and specific weak layers within stratified sequences appear to be the key factors influencing landslide occurrence. Elevated pore pressures can result from normal depositional processes or from transient processes such as earthquake shaking; historical evidence suggests that the majority of large submarine landslides are triggered by earthquakes. Because of their tsunamigenic potential, ocean-island flank collapses and rockslides in fjords have been identified as the most dangerous of all landslide related hazards. Published models of ocean-island landslides mainly examine 'worst-case scenarios' that have a low probability of occurrence. Areas prone to submarine landsliding are relatively easy to identify, but we are still some way from being able to forecast individual events with precision. Monitoring of critical areas where landslides might be imminent and modelling landslide consequences so that appropriate mitigation strategies can be developed would appear to be areas where advances on current practice are possible.

  1. Compartment Syndrome Following Snake Bite

    National Research Council Canada - National Science Library

    Dhar, Dinesh


    .... The local effects of snake bite include tissue necrosis, edema, and compartment syndrome. Patients may also be left with permanent physical deformities due to residual sequelae of the snake bite...

  2. Dual-Compartment Inflatable Suitlock (United States)

    Kennedy, Kriss J.; Guirgis, Peggy L.; Boyle, Robert M.


    There is a need for an improvement over current NASA Extravehicular Activity (EVA) technology. The technology must allow the capacity for quicker, more efficient egress/ingress, allow for shirtsleeve suit maintenance, be compact in transport, and be applicable to environments ranging from planetary surface (partial-g) to orbital or deep space zero-g environments. The technology must also be resistant to dust and other foreign contaminants that may be present on or around a planetary surface. The technology should be portable, and be capable of docking with a variety of habitats, ports, stations, vehicles, and other pressurized modules. The Dual-Compartment Inflatable Suitlock (DCIS) consists of three hard inline bulkheads, separating two cylindrical membrane-walled compartments. The Inner Bulkhead can be fitted with a variety of hatch types, docking flanges, and mating hardware, such as the Common Berthing Mechanism (CBM), for the purpose of mating with vehicles, habitats, and other pressurized modules. The Inner Bulkhead and Center Bulkhead function as the end walls of the Inner Compartment, which during operations, would stay pressurized, either matching the pressure of the habitat or acting as a lower-pressure transitional volume. The Inner Compartment contains donning/doffing fixtures and inner suit-port hatches. The Center Bulkhead has two integrated suit-ports along with a maintenance hatch. The Center Bulkhead and Outer Bulkhead function as the end walls of the Outer Compartment, which stays at vacuum during normal operations. This allows the crewmember to quickly don a suit, and egress the suitlock without waiting for the Outer Compartment to depressurize. The Outer Compartment can be pressurized infrequently for both nominal and off-nominal suit maintenance tasks, allowing shirtsleeve inspections and maintenance/repair of the environmental suits. The Outer Bulkhead has a pressure-assisted hatch door that stays open and stowed during EVA operations, but can

  3. Navigation and history of science: autopsy to submarine Kursk. Survival previsions were not sufficient

    Directory of Open Access Journals (Sweden)

    Ignacio Jáuregui-Lobera


    Full Text Available On August 12, 2000, Saturday, a Russian submarine of the Oscar II class, the K-141 Kursk, sank in the Barents Sea, while sailing as part of the "Summer-X Exercise" manoeuvres. The Kursk was a giant double-hulled submarine, with nine sealed compartments, considered impossible to be sunk. During the manoeuvres, at 08:51 local time, the Kursk requested permission to prepare a torpedo and it received the response "Dobro" (good in English. At 11:29:34 (07:29:50 UTC the Norwegian seismic monitoring network (NORSAR registered an earthquake of intensity 1.5 on the Richter scale at northeast of Murmansk, approximately 250 Km from Norway, and 80 Km from the Kola Peninsula. At 11:31:48, two minutes and fourteen seconds later, a second movement, 4.2 on the Richter scale and 250 times longer than the first, was recorded by different seismographs, even being detected in Alaska. It was equivalent to an explosion of 2-3 Tm of TNT. After a great confusion and propaganda, there was no choice other than to accept the facts: the Kursk had suffered two explosions, had sunk and the whole crew had perished. But what happened in that submarine? It seems clear that survival previsions were not sufficient.

  4. H Reactor (United States)

    Federal Laboratory Consortium — The H Reactor was the first reactor to be built at Hanford after World War II.It became operational in October of 1949, and represented the fourth nuclear reactor on...

  5. Geomorphic process fingerprints in submarine canyons (United States)

    Brothers, Daniel S.; ten Brink, Uri S.; Andrews, Brian D.; Chaytor, Jason D.; Twichell, David C.


    Submarine canyons are common features of continental margins worldwide. They are conduits that funnel vast quantities of sediment from the continents to the deep sea. Though it is known that submarine canyons form primarily from erosion induced by submarine sediment flows, we currently lack quantitative, empirically based expressions that describe the morphology of submarine canyon networks. Multibeam bathymetry data along the entire passive US Atlantic margin (USAM) and along the active central California margin near Monterey Bay provide an opportunity to examine the fine-scale morphology of 171 slope-sourced canyons. Log–log regression analyses of canyon thalweg gradient (S) versus up-canyon catchment area (A) are used to examine linkages between morphological domains and the generation and evolution of submarine sediment flows. For example, canyon reaches of the upper continental slope are characterized by steep, linear and/or convex longitudinal profiles, whereas reaches farther down canyon have distinctly concave longitudinal profiles. The transition between these geomorphic domains is inferred to represent the downslope transformation of debris flows into erosive, canyon-flushing turbidity flows. Over geologic timescales this process appears to leave behind a predictable geomorphic fingerprint that is dependent on the catchment area of the canyon head. Catchment area, in turn, may be a proxy for the volume of sediment released during geomorphically significant failures along the upper continental slope. Focused studies of slope-sourced submarine canyons may provide new insights into the relationships between fine-scale canyon morphology and down-canyon changes in sediment flow dynamics.

  6. Acute compartment syndrome in haemophilia. (United States)

    Rodriguez-Merchan, E Carlos


    Acute compartment syndrome (ACS) is characterized by an increase in pressure (intramuscular pressure) within a muscle compartment, which reduces capillary perfusion threatening tissue survival. Persistence of this increased pressure for a few hours will result in necrosis of muscle and nerve tissue, with contracture in the affected limb and permanent loss of function. For that reason, early treatment and diagnosis of ACS is fundamental. Diagnosis should be based on physical examination (pain on stretching the involved muscles) and on an objective measurement of the limb perfusion pressure (DBP minus intramuscular pressure) within the affected compartment. To obtain a reliable clinical diagnosis, the patient must be evaluated every 1-2  h. In children and in unconscious patients, where the level of pain cannot be appropriately determined, an accurate clinical diagnosis is unfeasible, hence the importance of measuring compartment pressure. A fasciotomy should be performed when the limb perfusion pressure is less than 30  mmHg when averaged over a 12-h period (monitored every 1-2  h). Only 16 studies have been published on haemophilic patients with ACS, which report on a total of 34 cases. If symptoms or pressure measurements are suggestive of ACS, an extensive fasciotomy will be required. Unfortunately, fasciotomy is not exempt from complications such as the need of subsequent surgery because of a delay in wound healing, the need of a skin graft, pain, cosmetic problems, nerve injury, permanent muscle weakness and chronic venous insufficiency. Overlooked compartment syndrome remains one of most common causes of malpractice lawsuits. In haemophilia, adequate substitution of coagulation factor must be the first step. The main principle of surgical treatment is an extensive fasciotomy.

  7. Addressing submarine geohazards through scientific drilling (United States)

    Camerlenghi, A.


    Natural submarine geohazards (earthquakes, volcanic eruptions, landslides, volcanic island flank collapses) are geological phenomena originating at or below the seafloor leading to a situation of risk for off-shore and on-shore structures and the coastal population. Addressing submarine geohazards means understanding their spatial and temporal variability, the pre-conditioning factors, their triggers, and the physical processes that control their evolution. Such scientific endeavour is nowadays considered by a large sector of the international scientific community as an obligation in order to contribute to the mitigation of the potentially destructive societal effects of submarine geohazards. The study of submarine geohazards requires a multi-disciplinary scientific approach: geohazards must be studied through their geological record; active processes must be monitored; geohazard evolution must be modelled. Ultimately, the information must be used for the assessment of vulnerability, risk analysis, and development of mitigation strategies. In contrast with the terrestrial environment, the oceanic environment is rather hostile to widespread and fast application of high-resolution remote sensing techniques, accessibility for visual inspection, sampling and installation of monitoring stations. Scientific Drilling through the IODP (including the related pre site-survey investigations, sampling, logging and in situ measurements capability, and as a platform for deployment of long term observatories at the surface and down-hole) can be viewed as the centre of gravity of an international, coordinated, multi-disciplinary scientific approach to address submarine geohazards. The IODP Initial Science Plan expiring in 2013 does not address openly geohazards among the program scientific objectives. Hazards are referred to mainly in relation to earthquakes and initiatives towards the understanding of seismogenesis. Notably, the only drilling initiative presently under way is the

  8. MVAC Submarine cable, impedance measurements and analysis

    DEFF Research Database (Denmark)

    Arentsen, Martin Trolle; Pedersen, Morten Virklund; Expethit, Adrian


    Due to environmental concerns an increase in off-shore windfarms has been observed in recent years, leading to an increased demand for three-core-wire-armoured submarine cables. However, the IEC Standard 60287 used to calculate the ampacity of these cables is widely recognized as being not accurate...

  9. German Submarine Offensives and South African Countermeasures

    African Journals Online (AJOL)


    'Good Hunting': German Submarine Offensives and South African. Countermeasures off the South African Coast during the Second World. War, 1942-1945. Evert Kleynhans. •. Abstract .... wolf packs south, Dönitz had hoped to cause a diversionary effect whereby the Allies would be forced to split their defensive forces ...

  10. Submarine Telecommunication Cables in Disputed Maritime Areas

    NARCIS (Netherlands)

    van Logchem, Youri


    There are a considerable number of maritime areas where no boundary exists, or where a boundary is delimited only in part. This article deals with the issue of submarine telecommunication cables, which are sometimes placed on the seabed or buried in the subsoil of areas that are claimed by multiple

  11. Chemical environments of submarine hydrothermal systems (United States)

    Shock, Everett L.


    Perhaps because black-smoker chimneys make tremendous subjects for magazine covers, the proposal that submarine hydrothermal systems were involved in the origin of life has caused many investigators to focus on the eye-catching hydrothermal vents. In much the same way that tourists rush to watch the spectacular eruptions of Old Faithful geyser with little regard for the hydrology of the Yellowstone basin, attention is focused on the spectacular, high-temperature hydrothermal vents to the near exclusion of the enormous underlying hydrothermal systems. Nevertheless, the magnitude and complexity of geologic structures, heat flow, and hydrologic parameters which characterize the geyser basins at Yellowstone also characterize submarine hydrothermal systems. However, in the submarine systems the scale can be considerably more vast. Like Old Faithful, submarine hydrothermal vents have a spectacular quality, but they are only one fascinating aspect of enormous geologic systems operating at seafloor spreading centers throughout all of the ocean basins. A critical study of the possible role of hydrothermal processes in the origin of life should include the full spectrum of probable environments. The goals of this chapter are to synthesize diverse information about the inorganic geochemistry of submarine hydrothermal systems, assemble a description of the fundamental physical and chemical attributes of these systems, and consider the implications of high-temperature, fluid-driven processes for organic synthesis. Information about submarine hydrothermal systems comes from many directions. Measurements made directly on venting fluids provide useful, but remarkably limited, clues about processes operating at depth. The oceanic crust has been drilled to approximately 2.0 km depth providing many other pieces of information, but drilling technology has not allowed the bore holes and core samples to reach the maximum depths to which aqueous fluids circulate in oceanic crust. Such

  12. Phase 1 Final Report: Titan Submarine (United States)

    Oleson, Steven R.; Lorenz, Ralph D.; Paul, Michael V.


    The conceptual design of a submarine for Saturn's moon Titan was a funded NASA Innovative Advanced Concepts (NIAC) Phase 1 for 2014. The proposal stated the desire to investigate what science a submarine for Titan's liquid hydrocarbon seas might accomplish and what that submarine might look like. Focusing on a flagship class science system (100 kg), it was found that a submersible platform can accomplish extensive science both above and below the surface of the Kraken Mare. Submerged science includes mapping using side-looking sonar, imaging and spectroscopy of the lake, as well as sampling of the lake's bottom and shallow shoreline. While surfaced, the submarine will not only sense weather conditions (including the interaction between the liquid and atmosphere) but also image the shoreline, as much as 2 km inland. This imaging requirement pushed the landing date to Titan's next summer period (2047) to allow for lighted conditions, as well as direct-to-Earth communication, avoiding the need for a separate relay orbiter spacecraft. Submerged and surfaced investigation are key to understanding both the hydrological cycle of Titan as well as gather hints to how life may have begun on Earth using liquid, sediment, and chemical interactions. An estimated 25 Mb of data per day would be generated by the various science packages. Most of the science packages (electronics at least) can be safely kept inside the submarine pressure vessel and warmed by the isotope power system.The baseline 90-day mission would be to sail submerged and surfaced around and through Kraken Mare investigating the shoreline and inlets to evaluate the sedimentary interaction both on the surface and then below. Depths of Kraken have yet to be sensed (Ligeia to the north is thought to be 200 m (656 ft) deep), but a maximum depth of 1,000 m (3,281 ft) for Kraken Mare was assumed for the design). The sub would spend 20 d at the interface between Kraken Mare and Ligeia Mare for clues to the drainage of

  13. Miocene Current-Modified Submarine Fans (United States)

    Arce Perez, L. E.; Snedden, J.; Fisher, W. L.


    In the southwestern Gulf of Mexico, new and newly reprocessed seismic data has revealed a series of large bedforms, with set thicknesses of 130 to 250 meters. These exhibit hummocky, oblique and shingled to parallel seismic clinoform reflections. This seismic package has a paleowater depth of 450 meters. Those shingled seismic reflections in offshore east Mexico are interpreted as contourite drift deposits. These Miocene-age contourites may be related to strong ocean bottom currents that modified submarine fans and transported sediment to the north. Those contourites were identified on older seismic data, but are better imaged and interpreted on this new data. Plans are to map out and investigate the origin and extent of fans and contourites that extends over a large area of the Gulf of Mexico. In the Early Miocene several submarine fans systems were formed by the sediment input related to orogenic activity in Mexico. Submarine fan development persisted into the Middle Miocene due to continued uplift and erosion of the Mexican landmass. Initial, contourites are small and close proximity to the deep-water fan. In the Late Miocene time, contourite drift field reached its maximum extent in the Mexican deepwater area, anchored on its southern end by a submarine mound. This mounded submarine fan is located in the offshore northeast Veracruz and can be linked to increased uplift and erosion of the Trans-Mexican volcanic belt. In the Miocene-Pliocene, the large contourite drift begins to diminish in size and scale and is moribund by the Pliocene, with establishment of oceanic circulation similar to the present day. This research is important to understand more about the Gulf of Mexico and also for the Miocene timeframe that is a key phase in the earth's history. The role of the change in bottom water flow during progressive closure of the equatorial seaway separating North and South America will also be investigated.

  14. Compartment syndrome in a neonate

    Directory of Open Access Journals (Sweden)

    Magdalena Santosa


    Full Text Available A neonate born with severe asphyxia and considerable risk of infection was treated with intravenous sodium bicarbonate and intravenous antibiotics. At the age of five days he developed edema of the right forearm, tense on palpation, painful, hyperemic, and the hand was pallor, hypesthetic with maceration of the fifth finger. The diagnosis of compartment syndrome was established but it was delayed at least for about 48 hours. Decompression by fasciotomy using the volar Henry approach was performed; after which the pathologic changes rapidly subsided.  The cause of this syndrome wasprobably due to intravenous sodium bicarbonate and repeated intravenous antibiotics. From this experience it is strongly emphasized that we have to be aware and able to diagnose compartment syndrome at the earliest possible time in severely ill neonates and children who have multiple intravenous injection. Daily inspection and careful evaluation of the condition at the site of the intravenous line will be very crucial to detect the syndrome.

  15. Method and apparatus to assess compartment syndrome (United States)

    Ueno, Toshiaki (Inventor); Hargens, Alan R. (Inventor); Yost, William T. (Inventor)


    A method and apparatus for measuring pressure buildup in a body compartment that encases muscular tissue. The method includes assessing the body compartment configuration and identifying the effect of pulsatile components on at least one compartment dimension. This process is used in preventing tissue necrosis, and in decisions of whether to perform surgery on the body compartment for prevention of Compartment Syndrome. An apparatus is used for measuring excess pressure in the body compartment having components for imparting ultrasonic waves such as a transducer, placing the transducer to impart the ultrasonic waves, capturing the reflected imparted ultrasonic waves, and converting them to electrical signals, a pulsed phase-locked loop device for assessing a body compartment configuration and producing an output signal, and means for mathematically manipulating the output signal to thereby categorize pressure build-up in the body compartment from the mathematical manipulations.

  16. Pressure management in compartment fires


    Hostikka, Simo; Kallada Janardhan, Rahul


    Fire-induced pressure has not been considered a threat for structural or occupant safety in apartment fires. The situation may be changing as the building envelopes are becoming much more air-tight due to the energy efficiency requirements and the construction of high-rise buildings. In this project, we investigated the effects of the building's air-tightness, ventilation configuration and the fire growth rate on the peak overpressures inside the fire compartment and smoke spread within the m...

  17. Reactor Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A


    The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.

  18. Reactor safeguards

    CERN Document Server

    Russell, Charles R


    Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

  19. Reactor operation

    CERN Document Server

    Shaw, J


    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  20. Abdominal Compartment Syndrome due to OHSS


    Firoozeh Veisi; Maryam Zangeneh; Shohreh Malekkhosravi; Negin Rezavand


    Abdominal compartment syndrome is a dangerous clinical situation, usually following abdominal injuries&operations. It is seldom observed in patients with gynecologic and obstetric problems. Abdominalcompartment syndrome may be consequence ovarian hyperstimulation syndrome. A 28-year-old womanpresented as a sever ovarian hyperstimulation.The increased IAP indicated that OHSS may beconsidered a compartment syndrome. Abdominal compartment syndrome needs laparotomy orparacentesis for reductio...

  1. 36 CFR 1192.127 - Sleeping compartments. (United States)


    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Sleeping compartments. 1192.127 Section 1192.127 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS... Intercity Rail Cars and Systems § 1192.127 Sleeping compartments. (a) Sleeping compartments required to be...

  2. 24 CFR 3280.111 - Toilet compartments. (United States)


    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Toilet compartments. 3280.111... Toilet compartments. Each toilet compartment shall be a minimum of 30 inches in width, except, when the toilet is located adjacent to the short dimension of the tub, the distance from the tub to the center...

  3. Research Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Martens, Frederick H. [Argonne National Laboratory; Jacobson, Norman H.


    This booklet discusses research reactors - reactors designed to provide a source of neutrons and/or gamma radiation for research, or to aid in the investigation of the effects of radiation on any type of material.

  4. Acute Compartment Syndrome of the Leg. (United States)

    Konda, Sanjit R; Kester, Benjamin S; Fisher, Nina; Behery, Omar A; Crespo, Alexander M; Egol, Kenneth A


    Acute compartment syndrome (ACS) is well known among orthopaedic surgeons. The timely diagnosis and management of ACS is crucial to avoiding its sequelae, including renal failure, ischemic contractures, and limb loss. Despite its relative importance, ACS poses a challenge to many residents and clinicians as diagnosis relies largely on clinical judgment. Timely diagnosis and thorough compartment release are essential to optimizing outcomes in ACS. This video highlights a clinical case in which compartment syndrome of the leg was considered, diagnosed, and surgically managed. This video will present the indications for compartment release and a video-guided demonstration of compartment checks using an arterial line transducer, a 4-compartment fasciotomy with 2 incisions, and temporizing vessel loop closure. Compartment syndrome can be a devastating complication of common fractures. It is essential that orthopaedic practitioners understand the immediacy of intervention. We have a responsibility to provide timely, accurate diagnosis along with expedient surgical management.

  5. Psychological Implications for Submarine Display Design (United States)


    This paper addresses a number of psychological issues pertaining to display design . We review the literature comparing 3-D and 2-D displays and...perceptual, cognitive and ecological factors that are relevant to display design for submarine environments. The Generative Transformational visual perception is outlined and the relevance of transformational theory to display design is discussed. The paper also discusses a number of

  6. Topology Model of the Flow around a Submarine Hull Form (United States)


    resistance and flow noise arising from flow-structure interaction, it is necessary to test the shape of the submarine , which includes the length-to...UNCLASSIFIED Topology Model of the Flow around a Submarine Hull Form S.-K. Lee Maritime Division Defence Science and Technology Group DST-Group–TR...3177 ABSTRACT A topology model constructed from surface-streamer visualisation describes the flow around a generic conventional submarine hull form at

  7. A Lanchester model of submarine attack on a carrier battlegroup


    Eagle, James N.


    A Lanchester model is developed for a battlegroup ASW engagement. Two variations are included. In the first, long-range missile firing submarines, short-range missile or torpedo firing submarines, and submarines firing only torpedoes distribute their attack uniformly over battlegroup escort ships and carriers. In the second variation, the attack is concentrated on the carriers. supported by the Naval War College NA

  8. CONVECTION REACTOR (United States)

    Hammond, R.P.; King, L.D.P.


    An homogeneous nuclear power reactor utilizing convection circulation of the liquid fuel is proposed. The reactor has an internal heat exchanger looated in the same pressure vessel as the critical assembly, thereby eliminating necessity for handling the hot liquid fuel outside the reactor pressure vessel during normal operation. The liquid fuel used in this reactor eliminates the necessity for extensive radiolytic gas rocombination apparatus, and the reactor is resiliently pressurized and, without any movable mechanical apparatus, automatically regulates itself to the condition of criticality during moderate variations in temperature snd pressure and shuts itself down as the pressure exceeds a predetermined safe operating value.

  9. Meta-Analysis of Data from the Submarine Ventilation Doctrine Test Program

    National Research Council Canada - National Science Library

    Hoover, J


    .... The Submarine Ventilation Doctrine Test Program was developed to address submarine-specific issues regarding the use of ventilation systems to control smoke and heat movement, maintain habitability...

  10. Acute compartment syndrome caused by uncontrolled hypothyroidism. (United States)

    Modi, Anar; Amin, Hari; Salzman, Matthew; Morgan, Farah


    Acute compartment syndrome is increased tissue pressure exceeding perfusion pressure in a closed compartment resulting in nerve and muscle ischemia. Common precipitating causes are crush injuries, burns, substance abuse, osseous or vascular limb trauma. This is a case of 42year old female with history of hypothyroidism who presented to emergency room with acute onset of severe pain and swelling in right lower extremity. Physical examination was concerning for acute compartment syndrome of right leg which was confirmed by demonstration of elevated compartmental pressures. No precipitating causes were readily identified. Further laboratory testing revealed uncontrolled hypothyroidism. Management included emergent fasciotomy and initiating thyroid hormone replacement. This case represents a rare association between acute compartment syndrome and uncontrolled hypothyroidism. We also discuss the pathogenesis of compartment syndrome in hypothyroid patients and emphasize the importance of evaluating for less common causes, particularly in setting of non-traumatic compartment syndrome. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Abdominal Compartment Syndrome due to OHSS

    Directory of Open Access Journals (Sweden)

    Firoozeh Veisi


    Full Text Available Abdominal compartment syndrome is a dangerous clinical situation, usually following abdominal injuries&operations. It is seldom observed in patients with gynecologic and obstetric problems. Abdominalcompartment syndrome may be consequence ovarian hyperstimulation syndrome. A 28-year-old womanpresented as a sever ovarian hyperstimulation.The increased IAP indicated that OHSS may beconsidered a compartment syndrome. Abdominal compartment syndrome needs laparotomy orparacentesis for reduction of pressure.

  12. Can intramuscular glucose levels diagnose compartment syndrome? (United States)

    Doro, Christopher J; Sitzman, Thomas J; O'Toole, Robert V


    Compartment syndrome is difficult to diagnose, particularly in patients who are not able to undergo adequate clinical examination. Current methods rely on pressure measurements within the compartment, have high false-positive rates, and do not reliably indicate presence of muscle ischemia. We hypothesized that measurement of intramuscular glucose and oxygen can identify compartment syndrome with high sensitivity and specificity. Compartment syndrome was created in 12 anesthetized adult mixed-sex beagles, in the craniolateral compartment of a lower leg, by infusion of lactated Ringer's solution with normal serum concentration of glucose. The contralateral leg served as a control. Hydrostatic pressure, oxygen tension, and glucose concentration were recorded with commercially available probes. Compartment syndrome was maintained for 8 hours, and the animals were recovered. Two weeks later, compartment and control legs underwent muscle biopsy. Specimens were reviewed by a blinded pathologist. Within 15 minutes of creating compartment syndrome, glucose concentration and oxygen tension in the experimental limb were significantly lower than in the control limb (glucose, p = 0.02; oxygen, p = 0.007; two-tailed t test). Intramuscular glucose concentration of less than 97 mg/dL was 100% sensitive (95% confidence interval [CI], 73-100%) and 75% specific (95% CI, 40-94%) for the presence of compartment syndrome. Partial pressure of oxygen less than 30 mm Hg was 100% sensitive (95% CI, 72-100%) and 100% specific (95% CI, 69-100%) for the presence of compartment syndrome. Pathology confirmed compartment syndrome in all experimental limbs. Our results show that intramuscular glucose concentration and partial pressure of oxygen rapidly identify muscle ischemia with high sensitivity and specificity after experimentally created compartment syndrome in this animal model.

  13. Forearm Compartment Syndrome: Evaluation and Management. (United States)

    Kistler, Justin M; Ilyas, Asif M; Thoder, Joseph J


    Compartment syndrome of the forearm is uncommon but can have devastating consequences. Compartment syndrome is a result of osseofascial swelling leading to decreased tissue perfusion and tissue necrosis. There are numerous causes of forearm compartment syndrome and high clinical suspicion must be maintained to avoid permanent disability. The most widely recognized symptoms include pain out of proportion and pain with passive stretch of the wrist and digits. Early diagnosis and decompressive fasciotomy are essential in the treatment of forearm compartment syndrome. Closure of fasciotomy wounds can often be accomplished by primary closure but many patients require additional forms of soft tissue coverage procedures. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Australia’s Submarine Design Capabilities and Capacities: Challenges and Options for the Future Submarine (United States)


    General Dynamics Electric Boat Corporation EMC electromagnetic compatibility EMF electromagnetic field EMI electromagnetic interference EPCM flow-induced radiated noise Own-sensor performance degradation Note: Risks can be reduced for given designs using scale models...Acoustic analysis Addresses the total radiated noise signature of submarine designs Radiated noise that an enemy might detect Self-noise that that

  15. North Sea submarine cable disruptions and fishing activity

    NARCIS (Netherlands)

    Hintzen, N.T.; Machiels, M.A.M.


    At the North Sea seafloor, numerous submarine cables are positioned that connect telecommunication networks between countries. Worldwide, human activities cause most of the cable disruptions with fisheries accounting for nearly half of all reported faults. Due to a recent increase of submarine cable

  16. REACTOR COOLING (United States)

    Quackenbush, C.F.


    A nuclear reactor with provisions for selectively cooling the fuel elements is described. The reactor has a plurality of tubes extending throughout. Cylindrical fuel elements are disposed within the tubes and the coolant flows through the tubes and around the fuel elements. The fuel elements within the central portion of the reactor are provided with roughened surfaces of material. The fuel elements in the end portions of the tubes within the reactor are provlded with low conduction jackets and the fuel elements in the region between the central portion and the end portions are provided with smooth surfaces of high heat conduction material.

  17. The 1929 Grand Banks submarine landslide revisited (United States)

    Schulten, Irena; Mosher, David C.; Krastel, Sebastian; Piper, David J. W.; Kienast, Markus


    On November 18th, 1929 a large submarine landslide occurred along the St. Pierre Slope of the southwestern Grand Banks of Newfoundland, as a result of a Mw 7.2 earthquake. This submarine landslide led to the first recognition of naturally-occurring submarine turbidity currents and is one of the few landslides known to have generated a tsunami. The event caused 28 causalities in Newfoundland and severe infrastructural damage. Earlier investigations of the area identified widely distributed shallow mass failures (15 - 20 m high escarpments), but no evidence of a larger headscarp. It is difficult to conceive, therefore, how this distributed shallow failure that rapidly evolved into a turbidity current would have generated a tsunami. It is hypothesised in this study that a deeper rooted sediment failure ( 500 m), involving faulting and mass-rotation, was involved in the sediment failure and this displacement generated the tsunami. In order to test this hypothesis, the volume and kinematics of the 1929 slope failure are analysed by means of recently acquired high resolution seismic reflection and multibeam swath bathymetry data, in addition to a significant volume of legacy data. The data allow determination of: 1) the dimension of the failure area, 2) the thickness and volume of failed sediment on St. Pierre Slope, 3) fault patterns and displacements, and 4) styles of sediment failure involved. Shallow (20 m high) sinuous escarpments and a number of faults are observed along the upper St. Pierre Slope (500 - 2 500 m water depth). The uppermost and largest of these escarpments shows association with a fault system. Preliminary results, therefore, indicate a complex sediment failure pattern along the St. Pierre Slope, possibly involving a deep-seated decollement and mobilization of a large volume of surficial sediment through retrogressive failure. Causes for the tsunami are yet to be determined.

  18. Multivariable Control System Design for a Submarine, (United States)


    perturbations applied to the nominal point were identical in all cases (see table 2.3). The comparisons show excellent correlation between the...Open Loop Singular Values for the 5 and 1S Knot Linear Modelo *~~* b % % V’ , * % ~ .%~ C 9 ~ V. --.- V. V.-.--.--46..- S. 77’ Model S20R5 20- 10- -0...without imparting a pitch angle to the submarine and provides an excellent example of both the usefulness of w(t) as a state variable and the

  19. Hydrogen isotope systematics of submarine basalts (United States)

    Kyser, T.K.; O'Neil, J.R.


    The D/H ratios and water contents in fresh submarine basalts from the Mid-Atlantic Ridge, the East Pacific Rise, and Hawaii indicate that the primary D/H ratios of many submarine lavas have been altered by processes including (1) outgassing, (2) addition of seawater at magmatic temperature, and (3) low-temperature hydration of glass. Decreases in ??D and H2O+ from exteriors to interiors of pillows are explained by outgassing of water whereas inverse relations between ??D and H2O+ in basalts from the Galapagos Rise and the FAMOUS Area are attributed to outgassing of CH4 and H2. A good correlation between ??D values and H2O is observed in a suite of submarine tholeiites dredged from the Kilauea East Rift Zone where seawater (added directly to the magma), affected only the isotopic compositions of hydrogen and argon. Analyses of some glassy rims indicate that the outer millimeter of the glass can undergo lowtemperature hydration by hydroxyl groups having ??D values as low as -100. ??D values vary with H2O contents of subaerial transitional basalts from Molokai, Hawaii, and subaerial alkali basalts from the Society Islands, indicating that the primary ??D values were similar to those of submarine lavas. Extrapolations to possible unaltered ??D values and H2O contents indicate that the primary ??D values of most thoteiite and alkali basalts are near -80 ?? 5: the weight percentages of water are variable, 0.15-0.35 for MOR tholeiites, about 0.25 for Hawaiian tholeiites, and up to 1.1 for alkali basalts. The primary ??D values of -80 for most basalts are comparable to those measured for deep-seated phlogopites. These results indicate that hydrogen, in marked contrast to other elements such as Sr, Nd, Pb, and O, has a uniform isotopic composition in the mantle. This uniformity is best explained by the presence of a homogeneous reservoir of hydrogen that has existed in the mantle since the very early history of the Earth. ?? 1984.

  20. Chronic exertional compartment syndrome of the superficial posterior compartment: Soleus syndrome


    Christopher E Gross; Bela J Parekh; Samuel B Adams; Selene G Parekh


    Chronic exertional compartment syndrome (CECS) represents the second most-common cause of exertional leg pain with incidence of 27-33%. CECS of the superficial posterior compartment, or soleus syndrome, is rare and has only been discussed briefly in the literature. We discuss the management of two patients with bilateral soleus syndrome or CECS of the superficial posterior compartment.

  1. Chronic exertional compartment syndrome of the superficial posterior compartment: Soleus syndrome. (United States)

    Gross, Christopher E; Parekh, Bela J; Adams, Samuel B; Parekh, Selene G


    Chronic exertional compartment syndrome (CECS) represents the second most-common cause of exertional leg pain with incidence of 27-33%. CECS of the superficial posterior compartment, or soleus syndrome, is rare and has only been discussed briefly in the literature. We discuss the management of two patients with bilateral soleus syndrome or CECS of the superficial posterior compartment.

  2. Management of chronic exertional compartment syndrome

    African Journals Online (AJOL)

    Common symptoms were isolated muscle pain in the anterolateral compartments in all patients, paraesthesia in 15% and swelling in 10%. Post-exercise mean compartment pressure was 61 mmHg (normal <30 mmHg). Modified open fasciotomies were performed by lateral and medial incisions in lower limbs and by a ...

  3. Abdominal Compartment Syndrome in Surgical Patients

    African Journals Online (AJOL)

    level that the abdominal wall compliance threshold is exceeded and the abdomen can no longer stretch, at which point continued accumulation results in very high pressure within this compartment (2). The harmful effects of IAH occur long before the manifestation of compartment syndrome (3). When this is not recognized ...

  4. Clinical aspects of lower leg compartment syndrome

    NARCIS (Netherlands)

    Brand, Johan Gerard Henric van den


    A compartment syndrome is a condition in which increased pressure within a limited space compromises the circulation and function of tissues within that space. Although pathofysiology is roughly similar in chronic exertional and acute compartment syndrome of the lower leg, the clinical

  5. 49 CFR 38.127 - Sleeping compartments. (United States)


    ... 49 Transportation 1 2010-10-01 2010-10-01 false Sleeping compartments. 38.127 Section 38.127 Transportation Office of the Secretary of Transportation AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY SPECIFICATIONS FOR TRANSPORTATION VEHICLES Intercity Rail Cars and Systems § 38.127 Sleeping compartments. (a...

  6. Operational and accident survey of Russian nuclear submarines for risk assessments using statistical models for reliability growth

    Energy Technology Data Exchange (ETDEWEB)

    Reistad, Ole [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Osteras (Norway); Norwegian University of Science and Technology, Trondheim (Norway)], E-mail:; Hustveit, Styrkaar; Roudak, Svetlana [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Osteras (Norway)


    In this study, 165 safety related events involving Russian nuclear submarines from 1959 to 2007 are surveyed with respect to vessel generation, reactor type, various types of initiating event (loss-of-coolant accident (LOCA), transients, common cause initiators (CCI)), safety significance and the release of radioactivity. The survey of vessel operations shows that the accumulated number of vessel operating years (VOY)/reactor operating years (ROY) from 1959 to 2007 is 4991/9335. With respect to the survey of safety related events, out of the 165 events registered, there have been identified 17 accidents, 133 incidents and 15 deviations. As to event characteristics, 14 LOCA and 7 criticality events have been identified. The accident rates for each of the vessel generations exhibit the usual characteristics of a technological system under development, gradually going from a high accident rate to a stable lower level - however, with clear differences between reactor technologies (PWR versus LMC) and vessel generations. The mean-time between failures (MTBF) for various types of safety related events for the Russian nuclear submarines has been calculated for various events using the non-homogeneous Poisson process (NHPP) power-law model. When applied to the complete set of events, this model fails due to a cluster of safety related events that occurred between 1984 and 1987. With respect to releases of radioactivity, the MTBF has been calculated to 893 {+-} 138 VOY. All safety related events identified as part of this study are given in.

  7. Multifunctional reactors

    NARCIS (Netherlands)

    Westerterp, K.R.


    Multifunctional reactors are single pieces of equipment in which, besides the reaction, other functions are carried out simultaneously. The other functions can be a heat, mass or momentum transfer operation and even another reaction. Multifunctional reactors are not new, but they have received much

  8. Spontaneous Extensor Carpi Ulnaris Compartment Syndrome. (United States)

    Stewart, Sarah K; Singleton, James A G


    We report a case of isolated compartment syndrome within the extensor carpi ulnaris (ECU) compartment in the forearm of a 40-year-old diabetic man. Magnetic resonance imaging of his forearm showed isolated changes in the ECU muscle belly; compartment syndrome was confirmed on manometry. In view of the short history of symptoms and his diabetic status, the patient was managed conservatively. Twenty-four hours after onset of the symptoms, the pain and swelling resolved and he was able to be discharged. To date, 3 cases of ECU compartment syndrome secondary to trauma have been reported. This report illustrates a case of confirmed compartment syndrome without antecedent trauma, highly unusual in terms of both its etiology and its anatomical location. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  9. Flow dynamics around downwelling submarine canyons

    Directory of Open Access Journals (Sweden)

    J. M. Spurgin


    Full Text Available Flow dynamics around a downwelling submarine canyon were analysed with the Massachusetts Institute of Technology general circulation model. Blanes Canyon (northwestern Mediterranean was used for topographic and initial forcing conditions. Fourteen scenarios were modelled with varying forcing conditions. Rossby and Burger numbers were used to determine the significance of Coriolis acceleration and stratification (respectively and their impacts on flow dynamics. A new non-dimensional parameter (χ was introduced to determine the significance of vertical variations in stratification. Some simulations do see brief periods of upwards displacement of water during the 10-day model period; however, the presence of the submarine canyon is found to enhance downwards advection of density in all model scenarios. High Burger numbers lead to negative vorticity and a trapped anticyclonic eddy within the canyon, as well as an increased density anomaly. Low Burger numbers lead to positive vorticity, cyclonic circulation, and weaker density anomalies. Vertical variations in stratification affect zonal jet placement. Under the same forcing conditions, the zonal jet is pushed offshore in more uniformly stratified domains. The offshore jet location generates upwards density advection away from the canyon, while onshore jets generate downwards density advection everywhere within the model domain. Increasing Rossby values across the canyon axis, as well as decreasing Burger values, increase negative vertical flux at shelf break depth (150 m. Increasing Rossby numbers lead to stronger downwards advection of a passive tracer (nitrate, as well as stronger vorticity within the canyon. Results from previous studies are explained within this new dynamic framework.

  10. Submarine Tailings Disposal (STD—A Review

    Directory of Open Access Journals (Sweden)

    Bernhard Dold


    Full Text Available The mining industry is a fundamental industry involved in the development of modern society, but is also the world’s largest waste producer. This role will be enhanced in the future, because ore grades are generally decreasing, thus leading to increases in the waste/metal production ratio. Mine wastes deposited on-land in so-called tailings dams, impoundments or waste-dumps have several associated environmental issues that need to be addressed (e.g., acid mine drainage formation due to sulphide oxidation, geotechnical stability, among others, and social concerns due to land use during mining. The mining industry recognizes these concerns and is searching for waste management alternatives for the future. One option used in the past was the marine shore or shallow submarine deposition of this waste material in some parts of the world. After the occurrence of some severe environmental pollution, today the deposition in the deep sea (under constant reducing conditions is seen as a new, more secure option, due to the general thought that sulphide minerals are geochemically stable under the reduced conditions prevailing in the deep marine environment. This review highlights the mineralogical and geochemical issues (e.g., solubility of sulphides in seawater; reductive dissolution of oxide minerals under reducing conditions, which have to be considered when evaluating whether submarine tailings disposal is a suitable alternative for mine waste.

  11. Submarine melt rates under Greenland's ice tongues (United States)

    Wilson, Nat; Straneo, Fiametta; Heimbach, Patrick; Cenedese, Claudia


    The few remaining ice tongues (ice-shelf like extensions) of Greenland's glaciers are undergoing rapid changes with potential implications for the stability of the ice sheet. Submarine melting is recognized as a major contributor to mass loss, yet the magnitude and spatial distribution of melt are poorly known or understood. Here, we use high resolution satellite imagery to infer the magnitude and spatial variability of melt rates under Greenland's largest remaining ice tongues: Ryder Glacier, Petermann Glacier and Nioghalvfjerdsbræ (79 North Glacier). We find that submarine plus aerial melt approximately balance the ice flux from the grounded ice sheet for the first two while at Nioghalvfjerdsbræ the total melt flux exceeds the inflow of ice indicating thinning of the ice tongue. We also show that melt rates under the ice tongues vary considerably, exceeding 60 m yr-1 near the grounding zone and decaying rapidly downstream. Channels, likely originating from upstream subglacial channels, give rise to large melt variations across the ice tongues. Using derived melt rates, we test simplified melt parameterizations appropriate for ice sheet models and find the best agreement with those that incorporate ice tongue geometry in the form of depth and slope.

  12. Environmental assessment of submarine power cables

    Energy Technology Data Exchange (ETDEWEB)

    Isus, Daniel; Martinez, Juan D. [Grupo General Cable Sistemas, S.A., 08560-Manlleu, Barcelona (Spain); Arteche, Amaya; Del Rio, Carmen; Madina, Virginia [Tecnalia Research and Innovation, 20009 San Sebastian (Spain)


    Extensive analyses conducted by the European Community revealed that offshore wind energy have relatively benign effects on the marine environment by comparison to other forms of electric power generation [1]. However, the materials employed in offshore wind power farms suffer major changes to be confined to the marine environment at extreme conditions: saline medium, hydrostatic pressure... which can produce an important corrosion effect. This phenomenon can affect on the one hand, to the material from the structural viewpoint and on the other hand, to the marine environment. In this sense, to better understand the environmental impacts of generating electricity from offshore wind energy, this study evaluated the life cycle assessment for some new designs of submarine power cables developed by General Cable. To achieve this goal, three approaches have been carried out: leaching tests, eco-toxicity tests and Life Cycle Assessment (LCA) methodologies. All of them are aimed to obtaining quantitative data for environmental assessment of selected submarine cables. LCA is a method used to assess environmental aspects and potential impacts of a product or activity. LCA does not include financial and social factors, which means that the results of an LCA cannot exclusively form the basis for assessment of a product's sustainability. Leaching tests results allowed to conclude that pH of seawater did not significantly changed by the presence of submarine three-core cables. Although, it was slightly higher in case of broken cable, pH values were nearly equals. Concerning to the heavy metals which could migrate to the aquatic medium, there were significant differences in both scenarios. The leaching of zinc is the major environmental concern during undersea operation of undamaged cables whereas the fully sectioned three-core cable produced the migration of significant quantities of copper and iron apart from the zinc migrated from the galvanized steel. Thus, the tar

  13. What threat do turbidity currents and submarine landslides pose to submarine telecommunications cable infrastructure? (United States)

    Clare, Michael; Pope, Edward; Talling, Peter; Hunt, James; Carter, Lionel


    The global economy relies on uninterrupted usage of a network of telecommunication cables on the seafloor. These submarine cables carry ~99% of all trans-oceanic digital data and voice communications traffic worldwide, as they have far greater bandwidth than satellites. Over 9 million SWIFT banks transfers alone were made using these cables in 2004, totalling 7.4 trillion of transactions per day between 208 countries, which grew to 15 million SWIFT bank transactions last year. We outline the challenge of why, how often, and where seafloor cables are broken by natural causes; primarily subsea landslides and sediment flows (turbidity currents and also debris flows and hyperpycnal flows). These slides and flows can be very destructive. As an example, a sediment flow in 1929 travelled up to 19 m/s and broke 11 cables in the NE Atlantic, running out for ~800 km to the abyssal ocean. The 2006 Pingtung earthquake triggered a sediment flow that broke 22 cables offshore Taiwan over a distance of 450 km. Here, we present initial results from the first statistical analysis of a global database of cable breaks and causes. We first investigate the controls on frequency of submarine cable breaks in different environmental and geological settings worldwide. We assess which types of earthquake pose a significant threat to submarine cable networks. Meteorological events, such as hurricanes and typhoons, pose a significant threat to submarine cable networks, so we also discuss the potential impacts of future climate change on the frequency of such hazards. We then go on to ask what are the physical impacts of submarine sediment flows on submerged cables? A striking observation from past cable breaks is sometimes cables remain unbroken, whilst adjacent cables are severed (and record powerful flows travelling at up to 6 m/s). Why are some cables broken, but neighbouring cables remain intact? We provide some explanations for this question, and outline the need for future in

  14. Recurrent Lower-Extremity Compartment Syndrome after Four-Compartment Fasciotomy Secondary to Acute Limb Ischemia. (United States)

    Kerkar, Ashwini P; Farber, Alik; Kalish, Jeffrey A; Siracuse, Jeffrey J


    Lower-extremity compartment syndrome is a limb-threatening event necessitating emergent treatment using fasciotomy. Recurrent compartment syndrome is rare and has only been reported after trauma and in conjunction with underlying connective tissue disorders. In this report, we present a case of recurrent lower-extremity compartment syndrome caused by ischemia-reperfusion injury, in a patient previously treated with adequate 4-compartment fasciotomies. As such, this is the first reported case of recurrent compartment syndrome in the setting of ischemia-reperfusion injury that required treatment with 4-compartment fasciotomies on both occasions. This case demonstrates that fasciotomy is not protective against the development of recurrent compartment syndrome due to ischemia-reperfusion injury and that patients at high risk require monitoring. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine Program: Background and Issues for Congress (United States)


    propulsion technology first occurred many years ago: To help jumpstart the UK’s nuclear - powered submarine program, the United States transferred to the UK a... nuclear - powered attack submarines (SSNs), nuclear - powered cruise missile submarines (SSGNs), and nuclear - powered ballistic missile submarines (SSBNs). 2...2 In the designations SSN, SSGN, SSBN, and SSBN(X), the SS stands for submarine, N stands for nuclear - powered (meaning the ship is

  16. Compartment Syndrome of the Leg Associated With Fracture: An Algorithm to Avoid Releasing the Posterior Compartments. (United States)

    Tornetta, Paul; Puskas, Brian L; Wang, Kevin


    The purpose of this study is to report on a prospective series of patients in whom an algorithm was used to attempt to avoid releasing the posterior compartments in patients with lower leg compartment syndrome (CS) and the safety of such a practice. Prospective cohort study. Level 1 trauma center. A consecutive series of 39 patients was managed by one surgeon for CS using the reported protocol. Patients diagnosed with a CS of the leg were managed with a single operative protocol. After a standard anterior and lateral compartment release through a full-length lateral incision was performed, the superficial and deep posterior compartments were measured with the heel resting on a bolster. Using the preoperative diastolic blood pressure, a ΔP compartments. If the ΔP was ≥30, the posterior compartments were not released. Need for medial release or development of posterior CS or sequelae. A consecutive series of 39 patients were managed by 1 surgeon for CS using the described protocol. Two patients with an isolated posterior CS were excluded. The other 37 had clinical symptoms or compartment pressures consistent with anterior compartment involvement. Of 37 patients, 21 had (57%) symptoms suggesting posterior compartment involvement. The preoperative pressure measurements averaged 41 mm Hg with an average ΔP of 38. After full-length release of the anterior and lateral compartments, only 3/37 (8%) required a posterior release for a ΔP of compartments of the remaining 34 patients averaged 59 (32-86). The compartment pressures in the superficial and deep posterior compartments decreased by 22 mm Hg and 24 mm Hg, respectively, after the anterolateral release. None of the patients who had only an anterolateral release developed sequelae of a missed posterior CS. The use of the reported algorithm is effective in avoiding posterior compartment release. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

  17. Submarine landside in the Bussol Graben: Structural and formation features (United States)

    Baranov, B. V.; Lobkovsky, L. I.; Dozorova, K. A.; Rukavishnikova, D. D.


    Analysis of geophysical data obtained during a study of the insular slope in the central Kuril‒Kamchatka Trench during projects Kuriles-2005 and Kuriles-2006 promoted by the Presidium of the Russian Academy of Sciences revealed a large submarine landslide in this area. The landslide, located at the bottom of the transverse valley confined to the Bussol l Graben, resulted from the failure of the northeastern wall of a graben composed of sedimentary material. It exceeds 35 km3 in size, representing one of the large submarine landslides discovered to date on the slope of the Kuril‒Kamchatka Trench in submarine canyonfan environments.

  18. Management of demand based inventory aboard submarine tenders servicing attack (SSN) submarines


    Ross, Timothy Joseph


    Approved for public release; distribution is unlimited. This thesis examines the computation of inventory levels based on demand history aboard Submarine Tenders that use the Shipboard Automated Data Processing System (SUADPS) for inventory control. The focus of the thesis was the workload and supply effectiveness issues associated with the processing of the SUADPS levels setting program. The objective of the thesis was to determine the effect on supply effectiveness and stock churn if the...

  19. NUCLEAR REACTOR (United States)

    Miller, H.I.; Smith, R.C.


    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  20. Evaluation of acute compartment syndrome of extremities in ...

    African Journals Online (AJOL)

    Arun Kumar Agnihotri

    presenting with clinically suspected acute compartment syndrome were studied. These were divided into two age related groups: ... compartment syndrome in children; Acute compartment syndrome and fasciotomy. INTRODUCTIONᴪ ... immobilization, wound management, numbers of surgical procedures until definitive ...

  1. Submarine thermal springs on the Galapagos Rift (United States)

    Corliss, J.B.; Dymond, J.; Gordon, L.I.; Edmond, J.M.; Von Herzen, R. P.; Ballard, Richard D.; Green, K.; Williams, D.; Bainbridge, A.; Crane, K.; Van Andel, T. H.


    The submarine hydrothermal activity on and near the Galápagos Rift has been explored with the aid of the deep submersible Alvin. Analyses of water samples from hydrothermal vents reveal that hydrothermal activity provides significant or dominant sources and sinks for several components of seawater; studies of conductive and convective heat transfer suggest that two-thirds of the heat lost from new oceanic lithosphere at the Galápagos Rift in the first million years may be vented from thermal springs, predominantly along the axial ridge within the rift valley. The vent areas are populated by animal communities. They appear to utilize chemosynthesis by sulfur-oxidizing bacteria to derive their entire energy supply from reactions between the seawater and the rocks at high temperatures, rather than photosynthesis

  2. Improved OTEC System for a Submarine Robot (United States)

    Chao, Yi; Jones, Jack; Valdez, Thomas


    An ocean thermal energy conversion (OTEC), now undergoing development, is a less-massive, more-efficient means of exploiting the same basic principle as that of the proposed system described in "Alternative OTEC Scheme for a Submarine Robot" (NPO-43500), NASA Tech Briefs, Vol. 33, No. 1 (January 2009), page 50. The proposed system as described previously would be based on the thawing-expansion/freezing-contraction behavior of a wax or perhaps another suitable phase-change material (PCM). The power generated by the system would be used to recharge the batteries in a battery- powered unmanned underwater vehicle [UUV (essentially, a small exploratory submarine robot)] of a type that has been deployed in large numbers in research pertaining to global warming. A UUV of this type travels between the ocean surface and depths, measuring temperature and salinity. At one phase of its operational cycle, the previously proposed system would utilize the surface ocean temperature (which lies between 15 and 30 C over most of the Earth) to melt a PCM that has a melting/freezing temperature of about 10 C. At the opposite phase of its operational cycle, the system would utilize the lower ocean temperature at depth (e.g., between 4 and 7 C at a depth of 300 m) to freeze the PCM. The melting or freezing would cause the PCM to expand or contract, respectively, by about 9 volume percent. The PCM would be contained in tubes that would be capable of expanding and contracting with the PCM. The PCM-containing tubes would be immersed in a hydraulic fluid. The expansion and contraction would drive a flow of the hydraulic fluid against a piston that, in turn, would push a rack-and-pinion gear system to spin a generator to charge a battery.

  3. NUCLEAR REACTOR (United States)

    Grebe, J.J.


    High temperature reactors which are uniquely adapted to serve as the heat source for nuclear pcwered rockets are described. The reactor is comprised essentially of an outer tubular heat resistant casing which provides the main coolant passageway to and away from the reactor core within the casing and in which the working fluid is preferably hydrogen or helium gas which is permitted to vaporize from a liquid storage tank. The reactor core has a generally spherical shape formed entirely of an active material comprised of fissile material and a moderator material which serves as a diluent. The active material is fabricated as a gas permeable porous material and is interlaced in a random manner with very small inter-connecting bores or capillary tubes through which the coolant gas may flow. The entire reactor is divided into successive sections along the direction of the temperature gradient or coolant flow, each section utilizing materials of construction which are most advantageous from a nuclear standpoint and which at the same time can withstand the operating temperature of that particular zone. This design results in a nuclear reactor characterized simultaneously by a minimum critiral size and mass and by the ability to heat a working fluid to an extremely high temperature.

  4. 14 CFR 25.771 - Pilot compartment. (United States)


    ... compartment must be constructed so that, when flying in rain or snow, it will not leak in a manner that will distract the crew or harm the structure. (e) Vibration and noise characteristics of cockpit equipment may...

  5. A model for tidewater glacier undercutting by submarine melting (United States)

    Slater, D. A.; Nienow, P. W.; Goldberg, D. N.; Cowton, T. R.; Sole, A. J.


    Dynamic change at the marine-terminating margins of the Greenland Ice Sheet may be initiated by the ocean, particularly where subglacial runoff drives vigorous ice-marginal plumes and rapid submarine melting. Here we model submarine melt-driven undercutting of tidewater glacier termini, simulating a process which is key to understanding ice-ocean coupling. Where runoff emerges from broad subglacial channels we find that undercutting has only a weak impact on local submarine melt rate but increases total ablation by submarine melting due to the larger submerged ice surface area. Thus, the impact of melting is determined not only by the melt rate magnitude but also by the slope of the ice-ocean interface. We suggest that the most severe undercutting occurs at the maximum height in the fjord reached by the plume, likely promoting calving of ice above. It remains unclear, however, whether undercutting proceeds sufficiently rapidly to influence calving at Greenland's fastest-flowing glaciers.

  6. Submarine Upward Looking Sonar Ice Draft Profile Data and Statistics (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of upward looking sonar draft data collected by submarines in the Arctic Ocean. It includes data from both U.S. Navy and Royal Navy...

  7. Virtual Reality Training System for a Submarine Command Center

    National Research Council Canada - National Science Library

    Maxwell, Douglas B


    The invention as disclosed is a system that uses a combined real and virtual display interaction methodology to generate the visual appearance of submarine combat control rooms and allow interaction...

  8. Thigh compartment syndrome during extracorporeal life support. (United States)

    Kreibich, Maximilian; Czerny, Martin; Benk, Christoph; Beyersdorf, Friedhelm; Rylski, Bartosz; Trummer, Georg


    The aim of this study was to report our experience with patients on the extracorporeal life support system (ECLS) who presented with thigh compartment syndrome, a yet unreported complication. A retrospective analysis was performed from April 2003 to April 2017 to identify patients who presented to our department for treatment of acute compartment syndrome of the thigh after cannulation of the ECLS through the femoral artery and vein. Five patients, aged 30 to 84 years, who developed thigh compartment syndrome during ECLS therapy were identified. In three patients, the cause was arterial malperfusion; in one patient, the cause was venous malfunction and arterial malperfusion due to malposition of the arterial distal leg perfusion cannula in the femoral vein. The fifth patient suffered impaired venous drainage. Patients were on ECLS for 4 ± 2 days, and decompressive fasciotomy was performed in all patients 1 ± 1 days after ECLS commencement. Thigh compartment syndrome was responsible for significant morbidity, including prolonged open wound therapy, hospitalization, and leg amputation in one patient. Compartment syndrome of the thigh is a limb- and life-threatening complication and may occur in patients on ECLS. Angiographic or duplex ultrasound control of adequate limb perfusion and correct placement of the perfusion cannulas is recommended. Also, awareness of and close clinical observation for thigh perfusion and compartment syndrome are essential in patients during ECLS therapy. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  9. Studies on submarine control for periscope depth operations


    Tolliver, John V.


    Approved for public release; distribution in unlimited. Requirements for submarine periscope depth operations have been increased by integration with carrier battle groups, littoral operations, and contributions to joint surveillance. Improved periscope depth performance is therefore imperative. Submarine control personnel rely on a large number of analog gauges and indications. An integrated digital display system could enhance the ergonomics of the human control interface and display add...

  10. Exercise Aboard Attack Submarines: Rationale and New Options (United States)


    experience loss of physical fitness while underway. Bennett and co-workers (2) noted a 7% reduction of maximal oxygen consumption in non-exercising...Inc. designed and built a comprehensive resistance exercise device to help counteract muscle deconditioning during long term space flights (the SX... Physical activity aboard nuclear submarines as measured by pedometry. Groton: Naval Submarine Medical Research Laboratory, Report 1053, 1985, p. 12

  11. Are tilt measurements useful in detecting tsunamigenic submarine landslides?


    Sascha Brune; Andrey Babeyko; Stephan V. Sobolev


    Large submarine landslides can generate dangerous tsunamis. Because of their long-period signal, detection of landslides by common seismological methods is difficult. Here we suggest a method of detecting submarine landslides by using an array of land-based tiltmeters. The displacement of a large volume of sediments during landsliding produces a detectable elastic response of the lithosphere. We propose a technique to calculate this response and to invert for tsunami relevant parameters like ...

  12. The development of permafrost bacterial communities under submarine conditions (United States)

    Mitzscherling, Julia; Winkel, Matthias; Winterfeld, Maria; Horn, Fabian; Yang, Sizhong; Grigoriev, Mikhail N.; Wagner, Dirk; Overduin, Pier P.; Liebner, Susanne


    Submarine permafrost is more vulnerable to thawing than permafrost on land. Besides increased heat transfer from the ocean water, the penetration of salt lowers the freezing temperature and accelerates permafrost degradation. Microbial communities in thawing permafrost are expected to be stimulated by warming, but how they develop under submarine conditions is completely unknown. We used the unique records of two submarine permafrost cores from the Laptev Sea on the East Siberian Arctic Shelf, inundated about 540 and 2500 years ago, to trace how bacterial communities develop depending on duration of the marine influence and pore water chemistry. Combined with geochemical analysis, we quantified total cell numbers and bacterial gene copies and determined the community structure of bacteria using deep sequencing of the bacterial 16S rRNA gene. We show that submarine permafrost is an extreme habitat for microbial life deep below the seafloor with changing thermal and chemical conditions. Pore water chemistry revealed different pore water units reflecting the degree of marine influence and stages of permafrost thaw. Millennia after inundation by seawater, bacteria stratify into communities in permafrost, marine-affected permafrost, and seabed sediments. In contrast to pore water chemistry, the development of bacterial community structure, diversity, and abundance in submarine permafrost appears site specific, showing that both sedimentation and permafrost thaw histories strongly affect bacteria. Finally, highest microbial abundance was observed in the ice-bonded seawater unaffected but warmed permafrost of the longer inundated core, suggesting that permafrost bacterial communities exposed to submarine conditions start to proliferate millennia after warming.

  13. Cardiometabolic Health in Submariners Returning from a 3-Month Patrol

    Directory of Open Access Journals (Sweden)

    Heath G. Gasier


    Full Text Available Confined space, limited exercise equipment, rotating shift work and reduced sleep may affect cardiometabolic health in submariners. To test this hypothesis, 53 male U.S. Submariners (20–39 years were studied before and after a 3-month routine submarine patrol. Measures included anthropometrics, dietary and physical activity, biomarkers of cardiometabolic health, energy and appetite regulation, and inflammation. Before deployment, 62% of submariners had a body fat % (BF% ≥ 25% (obesity, and of this group, 30% met the criteria for metabolic syndrome. In obese volunteers, insulin, the homeostatic model assessment of insulin resistance (HOMA-IR, leptin, the leptin/adiponectin ratio, and pro-inflammatory chemokines growth-related oncogene and macrophage-derived chemokine were significantly higher compared to non-obese submariners. Following the patrol, a significant mean reduction in body mass (5% and fat-mass (11% occurred in the obese group as a result of reduced energy intake (~2000 kJ during the patrol; and, independent of group, modest improvements in serum lipids and a mean reduction in interferon γ-induced protein 10 and monocyte chemotactic protein 1 were observed. Since 43% of the submariners remained obese, and 18% continued to meet the criteria for metabolic syndrome following the patrol, the magnitude of weight loss was insufficient to completely abolish metabolic dysfunction. Submergence up to 3-months, however, does not appear to be the cause of obesity, which is similar to that of the general population.

  14. Solution of Supplee's submarine paradox through special and general relativity

    CERN Document Server

    Vieira, R S


    In 1989 Supplee described an apparent relativistic paradox on which a submarine seems to sink in a given frame while floating in another one. If the submarine density is adjusted to be the same as the water density (when both of them are at rest) and then it is put to move, the density of the submarine will become higher than that of the water, thanks to Lorentz contraction, and hence it sinks. However, in the submarine proper frame, is the water that becomes denser, so the submarine supposedly should float and we get a paradox situation. In this paper we analyze the submarine paradox in both a flat and a curved spacetime. In the case of a flat spacetime, we first show that any relativistic force field in special relativity can be written in the Lorentz form, so that it can always be decomposed into a static (electric-like) and a dynamic (magnetic-like) part. Taking into account the gravitomagnetic effects between the Earth and the water, a relativistic formulation of Archimedes principle can be established, ...

  15. Submarine Landslides at Santa Catalina Island, California (United States)

    Legg, M. R.; Francis, R. D.


    Santa Catalina Island is an active tectonic block of volcanic and metamorphic rocks originally exposed during middle Miocene transtension along the evolving Pacific-North America transform plate boundary. Post-Miocene transpression created the existing large pop-up structure along the major strike-slip restraining bend of the Catalina fault that forms the southwest flank of the uplift. Prominent submerged marine terraces apparent in high-resolution bathymetric maps interrupt the steep submarine slopes in the upper ~400 meters subsea depths. Steep subaerial slopes of the island are covered by Quaternary landslides, especially at the sea cliffs and in the blueschist metamorphic rocks. The submarine slopes also show numerous landslides that range in area from a few hectares to more than three sq-km (300 hectares). Three or more landslides of recent origin exist between the nearshore and first submerged terrace along the north-facing shelf of the island's West End. One of these slides occurred during September 2005 when divers observed a remarkable change in the seafloor configuration after previous dives in the area. Near a sunken yacht at about 45-ft depth where the bottom had sloped gently into deeper water, a "sinkhole" had formed that dropped steeply to 100-ft or greater depths. Some bubbling sand was observed in the shallow water areas that may be related to the landslide process. High-resolution multibeam bathymetry acquired in 2008 by CSU Monterey Bay show this "fresh" slide and at least two other slides of varying age along the West End. The slides are each roughly 2 hectares in area and their debris aprons are spread across the first terrace at about 85-m water depth that is likely associated with the Last Glacial Maximum sealevel lowstand. Larger submarine slides exist along the steep Catalina and Catalina Ridge escarpments along the southwest flank of the island platform. A prominent slide block, exceeding 3 sq-km in area, appears to have slipped more than

  16. Reactor Neutrinos

    CERN Document Server

    Lasserre, T; Lasserre, Thierry; Sobel, Henry W.


    We review the status and the results of reactor neutrino experiments, that toe the cutting edge of neutrino research. Short baseline experiments have provided the measurement of the reactor neutrino spectrum, and are still searching for important phenomena such as the neutrino magnetic moment. They could open the door to the measurement of coherent neutrino scattering in a near future. Middle and long baseline oscillation experiments at Chooz and KamLAND have played a relevant role in neutrino oscillation physics in the last years. It is now widely accepted that a new middle baseline disappearance reactor neutrino experiment with multiple detectors could provide a clean measurement of the last undetermined neutrino mixing angle theta13. We conclude by opening on possible use of neutrinos for Society: NonProliferation of Nuclear materials and Geophysics.

  17. NEUTRONIC REACTORS (United States)

    Wigner, E.P.; Young, G.J.


    A method is presented for loading and unloading rod type fuel elements of a neutronic reactor of the heterogeneous, solld moderator, liquid cooled type. In the embodiment illustrated, the fuel rods are disposed in vertical coolant channels in the reactor core. The fuel rods are loaded and unloaded through the upper openings of the channels which are immersed in the coolant liquid, such as water. Unloading is accomplished by means of a coffer dam assembly having an outer sleeve which is placed in sealing relation around the upper opening. A radiation shield sleeve is disposed in and reciprocable through the coffer dam sleeve. A fuel rod engaging member operates through the axial bore in the radiation shield sleeve to withdraw the fuel rod from its position in the reactor coolant channel into the shield, the shield snd rod then being removed. Loading is accomplished in the reverse procedure.

  18. ROV Tiburon Investigation of Hawaiian Submarine Canyons (United States)

    Paull, C. K.; Greene, H. G.; Caress, D. W.; Clague, D. A.; Ussler, W.; Maher, N. M.


    MBARI conducted ROV dives around the Hawaiian Islands during an expedition of the R/V Western Flyer and Tiburon in the spring of 2001. Eight ROV dives were made to investigate five major submarine canyons offshore of Oahu, Molokai, and Hawaii in up to 3,434 m water depths. Four of these canyons are located off the windward (northern) side of these islands where onshore canyons are also well developed. Those canyons located offshore of Molokai and Oahu incise the head scars of the giant Nuuanu and Wailai submarine landslides. ROV observations and sediment and rock outcrop sampling were made in these canyons to determine their origin and present-day activity. The fifth canyon investigated is located on the leeward (southern) side of Molokai. The canyons along the windward side expose extensive stratigraphic sections that reveal the history of the islands' formation. In composite, these sections contain marine pillow basalt overlain by a substantial sequence of alternating subaerial lava flows, rounded boulder conglomerates, shallow water carbonates, and hyaloclastites that indicate coastal and marine deposition. These sequences illustrate the accretion and subsequent subsidence of the islands' flanks. These canyons also have morphologically distinct upper and lower sections. The upper reaches of the canyons are incised into the shallow water marine facies and contain broad axial channels through which active sediment transport is occurring. In contrast, the morphology of the lower canyons are strongly influenced by the giant landslides that massively altered the northern flanks of the Hawaiian chain. The lower canyons contain plunge pools and steep headwall scarps that are generally comprised of mechanically competent subaerial lava flows. The presence of multiple plunge pools with differentially eroded head scarps suggests retrogressive erosion (bottom-up process) with headward advancement of the various heads. Undercutting of the headwalls also produce periodic

  19. Relationship between work stress and health in submariners

    Directory of Open Access Journals (Sweden)

    Nan-nan JIANG


    Full Text Available Objective To explore the relationship between work stress and health in submariners. Methods In April 2008, 272 submariners trained in a navy base were selected as study subjects by random group sampling method, and tested by primary personal information questionnaire, self-rated health measurement scale (SRHMS, self-developed submariners' work stressors questionnaire, and work stress self-rated scale. Physical health, mental health and social health of submariners were analyzed, and scores were compared with the norm of reference scores. Correlations were analyzed respectively between 10 items of submariners' general information (including age, length of military service, education degree, years at the present post, times of receiving awards, on-duty hours, off-duty hours, hours of sleep, lost days of leave, positive attitude to work and their physical health score, mental health score, social health score, total health score, as well as between 15 submariners' work stressors (including workrelated risks, diet problems, high temperature, humidity and noise in workplace, shortage of clean clothes, illness, losing contact with outside, lack of information about the task, lacking supports from family members, relationship problems, lack of involvement in task decisions, boring and dull work, on duty, heavy work, high quality of work, coping with unexpected threat and their physical health score, mental health score, social health score and total health score. Results No significant difference was found between submariners' SRHMS total score and the normal referenced score (t=0.56, P>0.05, but the physical health score and mental health score were significantly lower than normal referenced scores respectively (t=–2.172, P<0.05; t=–3.299, P<0.01, and the social health score was significantly higher than normal referenced score (t=9.331, P<0.001. The age, length of military service, years at present post of submariners were related

  20. Compartment syndrome in infants and toddlers. (United States)

    Broom, Alexander; Schur, Mathew D; Arkader, Alexandre; Flynn, John; Gornitzky, Alex; Choi, Paul D


    To study the cause, diagnosis, treatment and outcome of acute compartment syndrome in infants and toddlers aged compartment syndrome were identified from two large pediatric trauma centers over a fifteen-year period. All children underwent fasciotomy. The mechanism of injury, time of injury, time to diagnosis, compartment pressures, time to fasciotomy, and outcome at the time of the latest follow-up were recorded. Nine (60 %) of fifteen patients developed compartment syndrome secondary to trauma, four (4/15, 27 %) due to infection, and two (2/15, 13 %) due to intravenous infiltration. The average time from injury or hospital admission to fasciotomy was 31.8 h (range 2.9-136.3 h). In general, the functional outcome was excellent at the latest follow-up with thirteen (13/15, 87 %) patients having an excellent outcome. No cases of Volkmann's ischemia were noted at the time of fasciotomy, even when performed as late as 5 days after injury. Compared to the general pediatric population, the diagnosis of compartment syndrome in infants and toddlers may be further delayed, i.e., >24 h after injury. Despite delays in diagnosis and time to treatment, the present study shows that outcomes in infants and toddlers remain favorable even when fasciotomy is performed 48-72 h after injury. Case series, level IV.

  1. Iliopsoas compartment lesions: a radiologic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Leao, Alberto Ribeiro de Souza; Amaral, Raquel Portugal Guimaraes; Abud, Thiago Giansante; Demarchi, Guilherme Tadeu Sauaia; Freire Filho, Edison de Oliveira; Novack, Paulo Rogerio; Campos, Flavio do Amaral; Shigueoka, David Carlos; Fernandes, Artur da Rocha Correa; Szejnfeld, Jacob; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil). Dept. de Diagnostico por Imagem]. E-mail:; Santos, Jose Eduardo Mourao [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil)


    The iliopsoas compartment, a posterior boundary of the retroperitoneum, is comprised of the psoas major, psoas minor and iliac muscles. The symptoms picture in patients presenting with pathological involvement of this compartment may show a wide range of nonspecific clinical presentations that may lead to delayed diagnosis. However, in the search of an etiological diagnosis, it is already known that inflammation, tumors, and hemorrhages account for almost all the lesions affecting the iliopsoas compartment. By means of a retrospective analysis of radiological studies in patients with iliopsoas compartment lesions whose diagnosis was confirmed by anatomopathological evaluation or clinical follow-up, we have reviewed its anatomy as well as the main forms of involvement, with the purpose of identifying radiological signs that may help to narrow down the potential differential diagnoses. As each lesion is approached we will discuss the main radiological findings such as presence of gas in pyogenic abscesses, bone destruction and other bone changes of vertebral bodies in lesions secondary to tuberculosis, involvement of fascial planes in cases of neoplasms, and differences in signal density and intensity of hematomas secondary to hemoglobin degradation, among others. So, we have tried to present cases depicting the most frequent lesions involving the iliopsoas compartment, with emphasis on those signs that can lead us to a more specific etiological diagnosis. (author)

  2. From submarine to lacustrine groundwater discharge (United States)

    Lewandowski, Jörg; Meinikmann, Karin; Pöschke, Franziska; Nützmann, Gunnar; Rosenberry, Donald O.


    Submarine groundwater discharge (SGD) and its role in marine nutrient cycling are well known since the last decade. The freshwater equivalent, lacustrine groundwater discharge (LGD), is often still disregarded, although first reports of LGD are more than 50 years old. We identify nine different reasons why groundwater has long been disregarded in both freshwater and marine environments such as invisibility of groundwater discharge, the size of the interface and its difficult accessibility. Although there are some fundamental differences in the hydrology of SGD and LGD, caused primarily by seawater recirculation that occurs only in cases of SGD, there are also a lot of similarities such as a focusing of discharge to near-shore areas. Nutrient concentrations in groundwater near the groundwater–surface water interface might be anthropogenically enriched. Due to spatial heterogeneity of aquifer characteristics and biogeochemical processes, the quantification of groundwater-borne nutrient loads is challenging. Both nitrogen and phosphorus might be mobile in near-shore aquifers and in a lot of case studies large groundwater-borne nutrient loads have been reported.

  3. Design and analysis of submarine radome (United States)

    Sandeep, C. Satya; Prasad, U. Shiva; Suresh, R.; Rathan, A.; Sravanthi, G.; Govardhan, D.


    Radomes are the electromagnetic windows that protect microwave sub-systems from the environmental effects. The major requirement of radome is its transparency to microwaves and for most of the cases mechanical properties are also equally important. Radome for underwater applications has to withstand high water pressure of the order of 45 bars. Composite materials owing to their high strength to weight ratio, high stiffness and better corrosion resistance are potential source for under water applications. The concept of 'tailoring' the material properties to suit the radome is obtained by selecting proper reinforcement, resin matrix and their compositions. The mechanical properties of composite material, evaluated by testing specimens as per ASTM standards, are utilized in designing the radome. The modulus properties calculated using classical theories of composite materials and compared with test results. ANSYS a Finite Element software package used to analyse the problem. As the cross sectional thickness of radome varies, the complexity in fabrication is overcome by adopting matched die techniques. The radome design and finite element analysis validation concluded by conducting the pressure test on radome. On the design a modal analysis is also carried to check for the natural frequency, So that resonance does not occur if the natural frequency of the radome coincides with the excitation frequency of the submarine Clinical information system (CIS) for UNRWA is a computerized distributed application that used in clinics which follows the United Nations Relief and Works Agency (UNRWA) to manage the clinical requirements and services.

  4. Submarine landslides of the Southern California Borderland (United States)

    Lee, H.J.; Greene, H. Gary; Edwards, B.D.; Fisher, M.A.; Normark, W.R.


    Conventional bathymetry, sidescan-sonar and seismic-reflection data, and recent, multibeam surveys of large parts of the Southern California Borderland disclose the presence of numerous submarine landslides. Most of these features are fairly small, with lateral dimensions less than ??2 km. In areas where multibeam surveys are available, only two large landslide complexes were identified on the mainland slope- Goleta slide in Santa Barbara Channel and Palos Verdes debris avalanche on the San Pedro Escarpment south of Palos Verdes Peninsula. Both of these complexes indicate repeated recurrences of catastrophic slope failure. Recurrence intervals are not well constrained but appear to be in the range of 7500 years for the Goleta slide. The most recent major activity of the Palos Verdes debris avalanche occurred roughly 7500 years ago. A small failure deposit in Santa Barbara Channel, the Gaviota mudflow, was perhaps caused by an 1812 earthquake. Most landslides in this region are probably triggered by earthquakes, although the larger failures were likely conditioned by other factors, such as oversteepening, development of shelf-edge deltas, and high fluid pressures. If a subsequent future landslide were to occur in the area of these large landslide complexes, a tsunami would probably result. Runup distances of 10 m over a 30-km-long stretch of the Santa Barbara coastline are predicted for a recurrence of the Goleta slide, and a runup of 3 m over a comparable stretch of the Los Angeles coastline is modeled for the Palos Verdes debris avalanche. ?? 2009 The Geological Society of America.

  5. Seismic reflections associated with submarine gas hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Andreassen, K.


    Gas hydrates are often suggested as a future energy resource. This doctoral thesis improves the understanding of the concentration and distribution of natural submarine gas hydrates. The presence of these hydrates are commonly inferred from strong bottom simulating reflection (BSR). To investigate the nature of BSR, this work uses seismic studies of hydrate-related BSRs at two different locations, one where gas hydrates are accepted to exist and interpreted to be very extensive (in the Beaufort Sea), the other with good velocity data and downhole logs available (offshore Oregon). To ascertain the presence of free gas under the BSR, prestack offset data must supplement near-vertical incidence seismic data. A tentative model for physical properties of sediments partially saturated with gas hydrate and free gas is presented. This model, together with drilling information and seismic data containing the BSR beneath the Oregon margin and the Beaufort Sea, made it possible to better understand when to apply the amplitude-versus-offset (AVO) method to constrain BSR gas hydrate and gas models. Distribution of natural gas hydrates offshore Norway and Svalbard is discussed and interpreted as reflections from the base of gas hydrate-bearing sediments, overlying sediments containing free gas. Gas hydrates inferred to exist at the Norwegian-Svalbard continental margin correlate well with Cenozoic depocenters, and the associated gas is assumed to be mainly biogenic. Parts of that margin have a high potential for natural gas hydrates of both biogenic and thermogenic origin. 235 refs., 86 figs., 4 tabs.

  6. Submarine landslides in Arctic sedimentation: Canada Basin (United States)

    Mosher, David C.; Shimeld, John; Hutchinson, Deborah R.; Lebedova-Ivanova, N; Chapman, C.


    Canada Basin of the Arctic Ocean is the least studied ocean basin in the World. Marine seismic field programs were conducted over the past 6 years using Canadian and American icebreakers. These expeditions acquired more than 14,000 line-km of multibeam bathymetric and multi-channel seismic reflection data over abyssal plain, continental rise and slope regions of Canada Basin; areas where little or no seismic reflection data existed previously. Canada Basin is a turbidite-filled basin with flat-lying reflections correlateable over 100s of km. For the upper half of the sedimentary succession, evidence of sedimentary processes other than turbidity current deposition is rare. The Canadian Archipelago and Beaufort Sea margins host stacked mass transport deposits from which many of these turbidites appear to derive. The stratigraphic succession of the MacKenzie River fan is dominated by mass transport deposits; one such complex is in excess of 132,000 km2 in area and underlies much of the southern abyssal plain. The modern seafloor is also scarred with escarpments and mass failure deposits; evidence that submarine landsliding is an ongoing process. In its latest phase of development, Canada Basin is geomorphologically confined with stable oceanographic structure, resulting in restricted depositional/reworking processes. The sedimentary record, therefore, underscores the significance of mass-transport processes in providing sediments to oceanic abyssal plains as few other basins are able to do.

  7. Cutaneous anthrax cases leading compartment syndrome

    Directory of Open Access Journals (Sweden)

    Emine Parlak


    Full Text Available Bacillus anthracis is the causative agent of anthrax. Anthrax is a zoonotic disease with three clinical forms. Clinical forms are skin, gastrointestinal and inhalational anthrax. Cutaneous anthrax is 95% of the cases. Cutaneous anthrax frequently defines itself. Clinical presentation of anthrax may be severe and complicated in some cases. There may seem complications like meningitis, septic shock and compartment syndrome. Compartment Syndrome is a rare complication of cutaneous anthrax and it is life threatening. Physicians working in the endemic area should be aware of this form. In this study, three cases were shown which developed compartment syndrome following cutaneous anthrax. J Microbiol Infect Dis 2013;3(4: 214-217

  8. Neutronic reactor (United States)

    Wende, Charles W. J.; Babcock, Dale F.; Menegus, Robert L.


    A nuclear reactor includes an active portion with fissionable fuel and neutron moderating material surrounded by neutron reflecting material. A control element in the active portion includes a group of movable rods constructed of neutron-absorbing material. Each rod is movable with respect to the other rods to vary the absorption of neutrons and effect control over neutron flux.

  9. Neutronic reactor

    Energy Technology Data Exchange (ETDEWEB)

    Babcock, D.F.; Menegus, R.L.; Wende, C.W.


    A nuclear reactor includes an active portion with fissionable fuel and neutron moderating material surrounded by neutron reflecting material. A control element in the active portion includes a group of movable rods constructed of neutron-absorbing material. Each rod is movable with respect to the other rods to vary the absorption of neutrons and effect control over neutron flux.

  10. Space Shuttle crew compartment debris-contamination (United States)

    Goodman, Jerry R.; Villarreal, Leopoldo J.


    Remedial actions undertaken to reduce debris during manned flights and ground turnaround operations at Kennedy Space Center and Palmdale are addressed. They include redesign of selected ground support equipment and Orbiter hardware to reduce particularization/debris generation; development of new detachable filters for air-cooled avionics boxes; application of tape-on screens to filter debris; and implementation of new Orbiter maintenance and turnaround procedures to clean filters and the crew compartment. Most of these steps were implemented before the return-to-flight of STS-26 in September 1988 which resulted in improved crew compartment habitability and less potential for equipment malfunction.

  11. Forearm compartment syndrome secondary to leukemic infiltrates. (United States)

    Trumble, T


    A 20-year-old white man with leukemia was recently treated with chemotherapy and was admitted to the Massachusetts General Hospital with a fever and a swollen and painful left forearm that worsened despite intravenous antibiotics. The flexor forearm compartment pressures were elevated; therefore, surgical decompression of the flexor compartments was done. All the wound cultures were negative, and biopsy specimens of tissue showed leukemic infiltrates in the muscle and subcutaneous tissue. Tumor infiltrates may result in increased compartmental pressures, and the treatment of these lesions includes chemotherapy and/or radiation therapy to provide local control of the tumor.

  12. NSMRL: A Small Command with A Huge Presence for the Submarine Force

    National Research Council Canada - National Science Library

    Daniel, J. C; Lamb, Jerry


    "To protect the health and enhance the performance of our warfighters through focused submarine, diving and surface research solutions" is the mission of the Naval Submarine Medical Research Laboratory (NSMRL...

  13. Conduct and Support of Amphibious Operations from United States Submarines in World War II (United States)


    twelfth war patrol of the Gato class submarine (See photos 1 and 2). They made history as the only Americans to conduct an offensive landing on a...Naval History Vol. 2, no. 1 (April 1, 2003), 1. 4 This monograph features five Gato class submarines, and three V-class submarines, but also addresses...1993), 67. 6 Photo 2: USS Barb (SS 220), representing the five Gato class submarines that participated in Operation Torch. Barb’s crew also

  14. Index of Submarine Medical Officer’s Qualification Theses 1944-1974 (United States)



  15. Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine Program: Background and Issues for Congress (United States)


    Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine Program: Background and Issues for Congress Ronald O’Rourke Specialist in Naval...Affairs April 5, 2016 Congressional Research Service 7-5700 R41129 Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine...Replacement (SSBN[X]) Ballistic Missile Submarine Program Congressional Research Service Contents Introduction

  16. Editorial: Acute compartment syndrome | Gakuu | East African ...

    African Journals Online (AJOL)

    East African Orthopaedic Journal. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 8, No 2 (2014) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Editorial: Acute compartment syndrome. LN Gakuu. Abstract. No abstract.

  17. Osteotomy induced compartment syndrome: A case Report ...

    African Journals Online (AJOL)

    Acute Compartment Syndrome (ACS) is a known potential complication of trauma and surgery of the leg. Although routine intracompartment pressure monitoring may prevent many cases, a high index of suspicion and aggressive preventive measures are the mainstay of management especially in high-risk patients. In spite ...

  18. 14 CFR 29.853 - Compartment interiors. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Compartment interiors. 29.853 Section 29.853 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... in a common housing, seat belts, shoulder harnesses, and cargo and baggage tiedown equipment...

  19. Gluteal Compartment Syndrome Secondary to Pelvic Trauma

    Directory of Open Access Journals (Sweden)

    Fernando Diaz Dilernia


    Full Text Available Gluteal compartment syndrome (GCS is extremely rare when compared to compartment syndrome in other anatomical regions, such as the forearm or the lower leg. It usually occurs in drug users following prolonged immobilization due to loss of consciousness. Another possible cause is trauma, which is rare and has only few reports in the literature. Physical examination may show tense and swollen buttocks and severe pain caused by passive range of motion. We present the case of a 70-year-old man who developed GCS after prolonged anterior-posterior pelvis compression. The physical examination revealed swelling, scrotal hematoma, and left ankle extension weakness. An unstable pelvic ring injury was diagnosed and the patient was taken to surgery. Measurement of the intracompartmental pressure was measured in the operating room, thereby confirming the diagnosis. Emergent fasciotomy was performed to decompress the three affected compartments. Trauma surgeons must be aware of the possibility of gluteal compartment syndrome in patients who have an acute pelvic trauma with buttock swelling and excessive pain of the gluteal region. Any delay in diagnosis or treatment can be devastating, causing permanent disability, irreversible loss of gluteal muscles, sciatic nerve palsy, kidney failure, or even death.

  20. Lipidomics in tissues, cells and subcellular compartments

    National Research Council Canada - National Science Library

    Horn, Patrick J; Chapman, Kent D


    ...‐infusion MS, localization of lipids in tissues and cells by laser desorption/ionization MS, and even profiling of lipids in individual subcellular compartments by direct‐organelle MS. Applications of these approaches to achieve improved understanding of plant lipid metabolism, compartmentation and function are discussed.

  1. Volkmann's Ischaemic Contracture following acute compartment ...

    African Journals Online (AJOL)

    Setting: PCEA Kikuyu hospital. Methods: An eight year old boy was treated and followed up after he had suffered compartment syndrome on his left forearm. This occurred after he fell and sustained fractures of both radius and ulnar. He was put in a cast at a peripheral hospital. East African Orthopaedic Journal, Vol.

  2. Management of chronic exertional compartment syndrome | Islam ...

    African Journals Online (AJOL)

    South African Journal of Surgery ... Methods: A total of 123 patients with extremity muscle pain, swelling and paraesthesia during the last 10 years were evaluated from a prospective database with compartment pressures ... Open fasciotomy is safe and effective and should be considered as the preferred surgical procedure.

  3. Abdominal Compartment Syndrome in Surgical Patients | Muturi ...

    African Journals Online (AJOL)

    Background: The deleterious effects of intraabdominal hypertension and abdominal compartment syndrome, affect almost every system. Patients at risk are the critically ill, in whom it leads to alteredorgan perfusion and end organ dysfunction/failure. The five cases reported highlight the diagnostic and management ...

  4. Submarine fans: A critical retrospective (1950–2015

    Directory of Open Access Journals (Sweden)

    G. Shanmugam


    Full Text Available When we look back the contributions on submarine fans during the past 65 years (1950–2015, the empirical data on 21 modern submarine fans and 10 ancient deep-water systems, published by the results of the First COMFAN (Committee on FANs Meeting (Bouma et al., 1985a, have remained the single most significant compilation of data on submarine fans. The 1970s were the “heyday” of submarine fan models. In the 21st century, the general focus has shifted from submarine fans to submarine mass movements, internal waves and tides, and contourites. The purpose of this review is to illustrate the complexity of issues surrounding the origin and classification of submarine fans. The principal elements of submarine fans, composed of canyons, channels, and lobes, are discussed using nine modern case studies from the Mediterranean Sea, the Equatorial Atlantic, the Gulf of Mexico, the North Pacific, the NE Indian Ocean (Bay of Bengal, and the East Sea (Korea. The Annot Sandstone (Eocene–Oligocene, exposed at Peira-Cava area, SE France, which served as the type locality for the “Bouma Sequence”, was reexamined. The field details are documented in questioning the validity of the model, which was the basis for the turbidite-fan link. The 29 fan-related models that are of conceptual significance, developed during the period 1970–2015, are discussed using modern and ancient systems. They are: (1 the classic submarine fan model with attached lobes, (2 the detached-lobe model, (3 the channel-levee complex without lobes, (4 the delta-fed ramp model, (5 the gully-lobe model, (6 the suprafan lobe model, (7 the depositional lobe model, (8 the fan lobe model, (9 the ponded lobe model, (10 the nine models based on grain size and sediment source, (11 the four fan models based on tectonic settings, (12 the Jackfork debrite model, (13 the basin-floor fan model, (14 supercritical and subcritical fans, and (15 the three types of fan reservoirs. Each model is unique

  5. Process sedimentology of submarine fan deposits - new perspectives (United States)

    Postma, George


    To link submarine fan process sedimentology with sand distribution, sand body architecture, texture and fabric, the field geologist studies sedimentary facies, facies associations (fan elements) and stratigraphy. Facies analysis resides on factual knowledge of modern fan morphodynamics and physical modelling of en-masse sediment transport. Where do we stand after 55 years of submarine research, i.e. the date when the first submarine fan model was launched by Arnold Bouma in 1962? Since that date students of submarine fans have worked on a number of important, recurring questions concerned with facies analysis of submarine successions in outcrop and core: 1. What type of sediment transport produced the beds? 2. What facies can be related to initial flow conditions? 3. What is the significance of grain size jumps and bounding surface hierarchy in beds consisting of crude and spaced stratification (traction carpets)? Do these point to multi flow events or to flow pulsations by one and the same event? 4. What facies associations relate to the basic elements of submarine fans? 5. What are the autogenic and allogenic signatures in submarine fans? Particularly in the last decade, the enormous technical advancement helped to obtain high-quality data from observations of density flows in modern canyons, deep basins and deep-water delta slopes (refs 1,2,3). In combination with both physical (refs 4,5) and numerical modelling (ref 6) these studies broke new ground into our understanding of density flow processes in various submarine environments and have led to new concepts of submarine fan building by super- and subcritical high-density flow (ref 7). Do these new concepts provide better answers to our recurrent questions related to the morphodynamics of submarine fans and prediction of sand body architecture? In discussing this open question, I shall 1. apply the new concepts to a modern and ancient example of a channel-lobe-transition-zone (ref 8); 2. raise the problem of

  6. Design and properties of marine reactors and associated R and D

    Energy Technology Data Exchange (ETDEWEB)

    Gagarinski, A.; Ignatiev, V. [Russian Research Centre Kurchatov Inst., Moscow (Russian Federation); Devell, L. [Studsvik Eco and Safety AB, Nykoeping (Sweden)


    The report is a review of open information available in the USA, UK, France, Russia and other countries on the design and properties of marine reactors and associated R and D. First, a short discussion is given of the milestones and main trends for the development of nuclear-powered ships. Then a brief review is presented of features for ship reactor design. Light water and liquid metal cooled reactor technologies are described and reactor operating experiences for Russian ice-breakers assessed. Traditional and alternative civil uses of submarine and surface shipboard reactor technology in Russia and Japan are also treated. Finally, some problems connected with radioactive waste by the nuclear-powered fleet are briefly considered. 41 refs, 27 figs, 19 tabs.

  7. Nuclear Reactors. Revised. (United States)

    Hogerton, John F.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Among the topics discussed are: How Reactors Work; Reactor Design; Research, Teaching, and Materials Testing; Reactors (Research, Teaching and Materials); Production Reactors; Reactors for Electric Power…

  8. Photocatalytic reactor (United States)

    Bischoff, Brian L.; Fain, Douglas E.; Stockdale, John A. D.


    A photocatalytic reactor for processing selected reactants from a fluid medium comprising at least one permeable photocatalytic membrane having a photocatalytic material. The material forms an area of chemically active sites when illuminated by light at selected wavelengths. When the fluid medium is passed through the illuminated membrane, the reactants are processed at these sites separating the processed fluid from the unprocessed fluid. A light source is provided and a light transmitting means, including an optical fiber, for transmitting light from the light source to the membrane.

  9. Well Leg Compartment Syndrome After Abdominal Surgery

    DEFF Research Database (Denmark)

    Christoffersen, Jens Krogh; Hove, Lars Dahlgaard; Mikkelsen, Kim Lyngby


    BACKGROUND: Well leg compartment syndrome (WLCS) is a complication to abdominal surgery. We aimed to identify risk factors for and outcome of WLCS in Denmark and literature. METHODS: Prospectively collected claims to the Danish Patient Compensation Association (DPCA) concerning WLCS after abdominal...... surgery (p = 0.04). Duration of the abdominal surgery was 4 times as important as the diagnostic delay for severity of the final outcome. DNPR recorded 4 new cases/year, and half were reported to DPCA. CONCLUSION: The first 24 h following abdominal surgery of >4 h' duration with elevated legs observation...... for WLCS should be standard. Pain in the calf is indicative of WLCS, and elevated serum CK can support the diagnosis. Mannitol infusion and acute four-compartment fasciotomy of the lower leg is the treatment. The risk of severe outcome of WLCS increases with duration of the primary operation. A broad...

  10. Compartment syndrome in patients with haemophilia (United States)

    Donaldson, James; Goddard, Nicholas


    Background Acute compartment syndrome (ACS) is an uncommon but potentially devastating condition. Methods and results There are scattered case reports and case series in the literature of ACS in persons with haemophilia (PWH), and even fewer in PWH and inhibitors. The management of compartment syndrome in these scenarios is controversial and often anecdotal. In addition haematological outcomes are frequently quoted but functional outcomes are generally overlooked. This article aims to provide an overview of ACS and its contemporary management. We also review the literature and outcomes of patients with haemophilia who develop ACS in an effort to assess the best treatment modality. Conclusion In the majority of cases ACS settles with normalisation of the clotting cascade. Specialist haematological input is mandatory before surgical intervention should be considered, especially in PWH and inhibitors. PMID:26566325

  11. Multi-compartment Aerosol Transport Model

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, Joshua Allen; Santarpia, Joshua; Brotherton, Christopher M.; Omana, Michael Alexis; Rivera, Danielle; Lucero, Gabriel Anthony


    A simple aerosol transport model was developed for a multi-compartmented cleanroom. Each compartment was treated as a well-mixed volume with ventilating supply and return air. Gravitational settling, intercompartment transport, and leakage of exterior air into the system were included in the model. A set of first order, coupled, ordinary differential equations was derived from the conservation equations of aerosol mass and air mass. The system of ODEs was then solved in MATLAB using pre-existing numerical methods. The model was verified against cases of (1) constant inlet-duct concentration, and (2) exponentially decaying inlet-duct concentration. Numerical methods resulted in normalized error of less than 10 -9 when model solutions were compared to analytical solutions. The model was validated against experimental measurements from a single field test and showed good agreement in the shape and magnitude of the aerosol concentration profile with time.

  12. Postoperative gastric dilatation causing abdominal compartment syndrome

    Directory of Open Access Journals (Sweden)

    Krausz Michael M


    Full Text Available Abstract Objective To study the effect of postoperative gastric dilatation on intra-abdominal pressure (IAP. Design and setting Single case report from a primary teaching hospital. Patients and methods A 72-year-old woman demonstrated a sudden respiratory and cardiovascular collapse following resection of a retroperitoneal sarcoma. This collapse was caused by abdominal compartment syndrome due to gastric dilatation. Results The patient was re-explored, an enormously distended stomach was found with the nasogastric tube situated in a small sliding hernia which prevented drainage of the distended stomach. Re-positioning of the nasogastric tube, allowed the decompression of the stomach and the patient's condition immediately improved. Conclusion Acute abdominal distention following major abdominal surgery may result from acute gastric dilatation, leading to oliguria and increased airway pressures. Untreated gastric dilatation can cause abdominal compartment syndrome.

  13. Postoperative gastric dilatation causing abdominal compartment syndrome. (United States)

    Mahajna, Ahmad; Mitkal, Sharon; Krausz, Michael M


    To study the effect of postoperative gastric dilatation on intra-abdominal pressure (IAP). Single case report from a primary teaching hospital. A 72-year-old woman demonstrated a sudden respiratory and cardiovascular collapse following resection of a retroperitoneal sarcoma. This collapse was caused by abdominal compartment syndrome due to gastric dilatation. The patient was re-explored, an enormously distended stomach was found with the nasogastric tube situated in a small sliding hernia which prevented drainage of the distended stomach. Re-positioning of the nasogastric tube, allowed the decompression of the stomach and the patient's condition immediately improved. Acute abdominal distention following major abdominal surgery may result from acute gastric dilatation, leading to oliguria and increased airway pressures. Untreated gastric dilatation can cause abdominal compartment syndrome.

  14. Box model of radionuclide dispersion and radiation risk estimation for population in case of radioactivity release from nuclear submarine {number_sign}601 dumped in the Kara Sea

    Energy Technology Data Exchange (ETDEWEB)

    Yefimov, E.I.; Pankratov, D.V.; Ignatiev, S.V. [Inst. of Physics and Power Engineering, Obninsk (Russian Federation)


    When ships with nuclear reactors or nuclear materials aboard suffer shipwreck or in the case of burial or dumping of radioactive wastes, atmospheric fallout, etc., radionuclides may be released and spread in the sea, contaminating the sea water and the sea bottom. When a nuclear submarine (NS) is dumped this spread of activity may occur due to gradual core destruction by corrosion over many years. The objective of this paper is to develop a mathematical model of radionuclide dispersion and to assess the population dose and radiation risk for radionuclide release from the NS No. 601, with Pb-Bi coolant that was dumped in the Kara Sea.

  15. Isolated medial foot compartment syndrome after ankle sprain. (United States)

    Cortina, Josep; Amat, Carles; Selga, Jordi; Corona, Pablo Salvador


    Foot compartment syndrome is a serious potential complication of foot crush injury, fractures, surgery, and vascular injury. An acute compartment syndrome isolated to the medial compartment of the foot after suffering an ankle sprain is a rare complication. We report the case of a 31-year-old man who developed a medial foot compartment syndrome after suffering a deltoid ligament rupture at ankle while playing football. The patient underwent a medial compartment fasciotomy with resolution of symptoms. Compartment syndromes of the foot are rare and have been reported to occur after severe trauma. But, there are some reports in the literature of acute exertional compartment syndrome. In our case, the compartment syndrome appeared after an ankle sprain without vascular injuries associated. Copyright © 2013 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  16. Computed tomography of the cervical compartments on the computer tomogram

    Energy Technology Data Exchange (ETDEWEB)

    Zaunbauer, W.; Haertel, M.


    The computed tomographic anatomy of the cervical compartments, with emphasis on the fascial planes of the neck, is described. Typical disease processes within these fascial confined compartments have been documented.

  17. Decompressive laparotomy for abdominal compartment syndrome (United States)

    Kimball, E.; Malbrain, M.; Nesbitt, I.; Cohen, J.; Kaloiani, V.; Ivatury, R.; Mone, M.; Debergh, D.; Björck, M.


    Background The effect of decompressive laparotomy on outcomes in patients with abdominal compartment syndrome has been poorly investigated. The aim of this prospective cohort study was to describe the effect of decompressive laparotomy for abdominal compartment syndrome on organ function and outcomes. Methods This was a prospective cohort study in adult patients who underwent decompressive laparotomy for abdominal compartment syndrome. The primary endpoints were 28‐day and 1‐year all‐cause mortality. Changes in intra‐abdominal pressure (IAP) and organ function, and laparotomy‐related morbidity were secondary endpoints. Results Thirty‐three patients were included in the study (20 men). Twenty‐seven patients were surgical admissions treated for abdominal conditions. The median (i.q.r.) Acute Physiology And Chronic Health Evaluation (APACHE) II score was 26 (20–32). Median IAP was 23 (21–27) mmHg before decompressive laparotomy, decreasing to 12 (9–15), 13 (8–17), 12 (9–15) and 12 (9–14) mmHg after 2, 6, 24 and 72 h. Decompressive laparotomy significantly improved oxygenation and urinary output. Survivors showed improvement in organ function scores, but non‐survivors did not. Fourteen complications related to the procedure developed in eight of the 33 patients. The abdomen could be closed primarily in 18 patients. The overall 28‐day mortality rate was 36 per cent (12 of 33), which increased to 55 per cent (18 patients) at 1 year. Non‐survivors were no different from survivors, except that they tended to be older and on mechanical ventilation. Conclusion Decompressive laparotomy reduced IAP and had an immediate effect on organ function. It should be considered in patients with abdominal compartment syndrome. PMID:26891380

  18. Acute compartment syndrome of forearm and hand


    T Chandraprakasam; R Ashok Kumar


    The diagnosis and treatment of the acute compartment syndrome is of paramount importance. Unless the viscious cycle is intervened at an appropriately early time it will result in irreversible damage leading to disability. In this review article we are discussing the basic pathophysiological process through which the various aetiological factors causing increased compartmental pressure lead to the progressive death of muscles and nerves. We also discuss the various clinical features that aid i...

  19. A submarine volcanic eruption leads to a novel microbial habitat. (United States)

    Danovaro, Roberto; Canals, Miquel; Tangherlini, Michael; Dell'Anno, Antonio; Gambi, Cristina; Lastras, Galderic; Amblas, David; Sanchez-Vidal, Anna; Frigola, Jaime; Calafat, Antoni M; Pedrosa-Pàmies, Rut; Rivera, Jesus; Rayo, Xavier; Corinaldesi, Cinzia


    Submarine volcanic eruptions are major catastrophic events that allow investigation of the colonization mechanisms of newly formed seabed. We explored the seafloor after the eruption of the Tagoro submarine volcano off El Hierro Island, Canary Archipelago. Near the summit of the volcanic cone, at about 130 m depth, we found massive mats of long, white filaments that we named Venus's hair. Microscopic and molecular analyses revealed that these filaments are made of bacterial trichomes enveloped within a sheath and colonized by epibiotic bacteria. Metagenomic analyses of the filaments identified a new genus and species of the order Thiotrichales, Thiolava veneris. Venus's hair shows an unprecedented array of metabolic pathways, spanning from the exploitation of organic and inorganic carbon released by volcanic degassing to the uptake of sulfur and nitrogen compounds. This unique metabolic plasticity provides key competitive advantages for the colonization of the new habitat created by the submarine eruption. A specialized and highly diverse food web thrives on the complex three-dimensional habitat formed by these microorganisms, providing evidence that Venus's hair can drive the restart of biological systems after submarine volcanic eruptions.

  20. Does calving matter? Evidence for significant submarine melt (United States)

    Bartholomaus, Timothy C.; Larsen, Christopher F.; O’Neel, Shad


    During the summer in the northeast Pacific Ocean, the Alaska Coastal Current sweeps water with temperatures in excess of 12 °C past the mouths of glacierized fjords and bays. The extent to which these warm waters affect the mass balance of Alaskan tidewater glaciers is uncertain. Here we report hydrographic measurements made within Icy Bay, Alaska, and calculate rates of submarine melt at Yahtse Glacier, a tidewater glacier terminating in Icy Bay. We find strongly stratified water properties consistent with estuarine circulation and evidence that warm Gulf of Alaska water reaches the head of 40 km-long Icy Bay, largely unaltered. A 10–20 m layer of cold, fresh, glacially-modified water overlies warm, saline water. The saline water is observed to reach up to 10.4 °C within 1.5 km of the terminus of Yahtse Glacier. By quantifying the heat and salt deficit within the glacially-modified water, we place bounds on the rate of submarine melt. The submarine melt rate is estimated at >9 m d−1, at least half the rate at which ice flows into the terminus region, and can plausibly account for all of the submarine terminus mass loss. Our measurements suggest that summer and fall subaerial calving is a direct response to thermal undercutting of the terminus, further demonstrating the critical role of the ocean in modulating tidewater glacier dynamics.

  1. Submarine Construction in Germany (U-Bootbau in Deutschland), (United States)


    the IKL sister firm, Maschinenbau Gabler GmbH, also founded by Prof. Gabler, which, unlike IKL (involved solely in development), is a hardware...snorkels, radar masts, as well as wharf and dockside connections, for IKL and various submarine yards. Moreover, Maschinenbau Gabler is engaged in

  2. Dissolved Nutrients from Submarine Groundwater in Flic en Flac ...

    African Journals Online (AJOL)

    Abstract—The aim of this study was to investigate dissolved nutrients in a submarine groundwater discharge (SGD) in Flic en Flac lagoon on the west coast of the volcanic island of Mauritius. The SGD enters Flic en Flac lagoon through a thin blanket of unconsolidated sediment through a fracture system and is concentrated ...

  3. Dissolved Nutrients from Submarine Groundwater in Flic en Flac ...

    African Journals Online (AJOL)

    The aim of this study was to investigate dissolved nutrients in a submarine groundwater discharge (SGD) in Flic en Flac lagoon on the west coast of the volcanic island of Mauritius. The SGD enters Flic en Flac lagoon through a thin blanket of unconsolidated sediment through a fracture system and is concentrated along the ...

  4. Simulation of Wave-Plus-Current Scour beneath Submarine Pipelines

    DEFF Research Database (Denmark)

    Eltard-Larsen, Bjarke; Fuhrman, David R.; Sumer, B. Mutlu


    A fully coupled hydrodynamic and morphologic numerical model was utilized for the simulation of wave-plus-current scour beneath submarine pipelines. The model was based on incompressible Reynolds-averaged Navier–Stokes equations, coupled with k-ω turbulence closure, with additional bed and suspen...

  5. Sedimentary characteristics of samples collected from some submarine canyons

    NARCIS (Netherlands)

    Bouma, Arnold H.

    Oriented rectangular cores of 20.3 × 30.5 cm and 45.7 cm high have been collected in a number of submarine canyons off southern California (U.S.A.) and off the southern tip of Baja California (Mexico) for a detailed study of their sedimentary structures. By applying several methods, mainly X-ray

  6. 'Good Hunting': German submarine offensives and South African ...

    African Journals Online (AJOL)

    The first German submarine offensive in South African waters during 1942, Operation Eisbär, was aimed at striking a devastating blow to shipping off the South African coast. By the end of December 1942, an estimated 310 864 tons of shipping had been sunk through Operation Eisbär and the first U-cruiser operation alone.

  7. Cost Estimation Lessons Learned for Future Submarine Acquisition Programs (United States)


    North Carolina and New Mexico 30 General Dynamics Electric Boat “U.S. Navy Awards General Dynamics $14 Billion Contract for Eight Virginia- Class...NAVSEA Program Executive officer, Submarines PMO 450, June 1995. “New SSN Program Life Cycle Cost Estimate.” Naval Center for Cost Analysis: GE-1300

  8. [Acute compartment syndrome after a bowling game]. (United States)

    Meyer, C Y; Braun, K F; Huber-Wagner, S; Neu, J


    A 28-year-old male patient was initially conservatively treated by a general physician for muscle strain of the right calf after a bowling game. Due to increasing pain and swelling of the lower leg 5 days later, the differential diagnosis of a deep vein thrombosis was considered. Furthermore, the onset of neurological deficits and problems with raising the foot prompted inclusion of compartment syndrome in the differential diagnosis for the first time. Admission to hospital for surgical intervention was scheduled for the following day. At this point in time the laboratory results showed a negative d-dimer value and greatly increased C-reactive protein level. On day 6 a dermatofasciotomy was performed which revealed extensive muscular necrosis with complete palsy of the peroneal nerve. In the following lawsuit the patient accused the surgeon of having misdiagnosed the slow-onset compartment syndrome and thus delaying correct and mandatory treatment. The arbitration board ruled that the surgeon should have performed fasciotomy immediately on day 5 at the patient's consultation. The clinical presentation of progressive pain, swelling of the lower leg in combination with peroneal palsy must lead to the differential diagnosis of compartment syndrome resulting in adequate therapy. The delay of immediate surgery, therefore, was assessed to be faulty as this knowledge is to be expected of a surgeon.

  9. Salus: Kernel Support for Secure Process Compartments

    Directory of Open Access Journals (Sweden)

    Raoul Strackx


    Full Text Available Consumer devices are increasingly being used to perform security and privacy critical tasks. The software used to perform these tasks is often vulnerable to attacks, due to bugs in the application itself or in included software libraries. Recent work proposes the isolation of security-sensitive parts of applications into protected modules, each of which can be accessed only through a predefined public interface. But most parts of an application can be considered security-sensitive at some level, and an attacker who is able to gain inapplication level access may be able to abuse services from protected modules. We propose Salus, a Linux kernel modification that provides a novel approach for partitioning processes into isolated compartments sharing the same address space. Salus significantly reduces the impact of insecure interfaces and vulnerable compartments by enabling compartments (1 to restrict the system calls they are allowed to perform, (2 to authenticate their callers and callees and (3 to enforce that they can only be accessed via unforgeable references. We describe the design of Salus, report on a prototype implementation and evaluate it in terms of security and performance. We show that Salus provides a significant security improvement with a low performance overhead, without relying on any non-standard hardware support.

  10. An ongoing large submarine landslide at the Japan trench (United States)

    Nitta, S.; Kasaya, T.; Miura, S.; Kawamura, K.


    This paper deals with an active submarine landslide on a landward trench slope in the Japan trench. Studied area is located on the upper terrace ranging from 400 to 1200 m in water depth, off Sendai, northeast Japan. We have surveyed in detail the seabed topography using a multi narrow beam (hereafter MBES) and a subbottom profiler (hereafter SBP) during the cruise MR12-E02 of R/V Mirai. The survey lines were 12 lines in N-S, and 3 lines in E-W, and situated in the region from 141°45'E, 37°40'N to 142°33'E, 38°32'N. Moreover, we used multi-channel seismic profile by the cruise KR04-10 of R/V Kairei in the interpretation of the SBP results. In general, horseshoe-shaped depressions of about 100 km wide along the trench slope are arrayed along the Japan trench. It has thought that they were formed by large submarine landslides, but we could not understand critically the relationship between the depressions and the submarine landslides. Based on the survey results, we found signals of an active submarine landslide in the depression as follows. 1) We observed arcuate-shaped lineaments, which are sub-parallel to a horseshoe-shaped depression. The lineaments concentrate in the south region from 38°N at about 20 km wide. These lineaments are formed by deformation structures as anticlines, synclines and normal fault sense displacements. 2) Most of the synclines and anticlines are not buried to form the lineaments. 3) Normal faults cutting about 1 km deep are observed in a multi-channel seismic profile. The normal faults are located just below the arcuate-shaped lineaments, and are tilted eastward being the downslope direction. It indicates a large submarine landslide. We concluded that the arcuate-shaped lineaments were generated by surface sediment movement with the submarine landsliding. We think that the submarine landslide of about 20 km wide and about 1 km thick move continuously down the landward trench slope. This would be the formation process of the horseshoe

  11. Hybrid adsorptive membrane reactor

    Energy Technology Data Exchange (ETDEWEB)

    Tsotsis, Theodore T [Huntington Beach, CA; Sahimi, Muhammad [Altadena, CA; Fayyaz-Najafi, Babak [Richmond, CA; Harale, Aadesh [Los Angeles, CA; Park, Byoung-Gi [Yeosu, KR; Liu, Paul K. T. [Lafayette Hill, PA


    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  12. D and DR Reactors (United States)

    Federal Laboratory Consortium — The world's second full-scale nuclear reactor was the D Reactor at Hanford which was built in the early 1940's and went operational in December of 1944.D Reactor ran...

  13. Modular Lead-Bismuth Fast Reactors in Nuclear Power

    Directory of Open Access Journals (Sweden)

    Vladimir Petrochenko


    Full Text Available On the basis of the unique experience of operating reactors with heavy liquid metal coolant–eutectic lead-bismuth alloy in nuclear submarines, the concept of modular small fast reactors SVBR-100 for civilian nuclear power has been developed and validated. The features of this innovative technology are as follows: a monoblock (integral design of the reactor with fast neutron spectrum, which can operate using different types of fuel in various fuel cycles including MOX fuel in a self-providing mode. The reactor is distinct in that it has a high level of self-protection and passive safety, it is factory manufactured and the assembled reactor can be transported by railway. Multipurpose application of the reactor is presumed, primarily, it can be used for regional power to produce electricity, heat and for water desalination. The Project is being realized within the framework of state-private partnership with joint venture OJSC “AKME-Engineering” established on a parity basis by the State Atomic Energy Corporation “Rosatom” and the Limited Liability Company “EuroSibEnergo”.

  14. Reactor transient

    Energy Technology Data Exchange (ETDEWEB)

    Menegus, R.L.


    The authors are planning a calculation to be done on the Univac at the Louviers Building to estimate the effect of xenon transients, a high reactor power. This memorandum outlines the reasons why they prefer to do the work at Louviers rather than at another location, such as N.Y.U. They are to calculate the response of the reactor to a sudden change in position of the half rods. Qualitatively, the response will be a change in the rooftop ratio of the neutron flux. The rooftop ratio may oscillate with high damping, or, instead, it may oscillate for many cycles. It has not been possible for them to determine this response by hand calculation because of the complexity of the problem, and yet it is important for them to be certain that high power operation will not lead us to inherently unstable operation. Therefore they have resorted to machine computation. The system of differential equations that describes the response has seven dependent variables; therefore there are seven equations, each coupled with one or more of the others. The authors have discussed the problem with R.R. Haefner at the plant, and it is his opinion that the IBM 650 cannot adequately handle the system of seven equations because the characteristic time constants vary over a range of about 10{sup 8}. The Univac located at the Louviers Building is said to be satisfactory for this computation.

  15. Innovative inspection system for reactor pressure vessels; Innovative Pruefsysteme fuer Reaktordruckbehaelter

    Energy Technology Data Exchange (ETDEWEB)

    Mertens, K.; Trautmann, H.


    The versatile, compact and modern underwater systems described, the DELPHIN manipulators and MIDAS submarines, are innovative systems enabling RPV inspections at considerably reduced efforts and time, thus reducing the total time required for ISI of reactors. (orig./CB) [Deutsch] Die vorgestellten kleinen, flexiblen und modernen Schwimmsysteme (DELPHIN-Manipulatoren und MIDAS-U-Boote) sind innovative Systeme fuer die Reduzierung der Aufwaende und Zeit zur Pruefung des Reaktordruckbehaelters und damit zur Reduktion der Revisionszeiten der Reaktoranlagen. (orig.)

  16. Exploring the submarine Graham Bank in the Sicily Channel

    Directory of Open Access Journals (Sweden)

    Mauro Coltelli


    Full Text Available In the Sicily Channel, volcanic activity has been concentrated mainly on the Pantelleria and Linosa islands, while minor submarine volcanism took place in the Adventure, Graham and Nameless banks. The volcanic activity spanned mostly during Plio-Pleistocene, however, historical submarine eruptions occurred in 1831 on the Graham Bank and in 1891 offshore Pantelleria Island. On the Graham Bank, 25 miles SW of Sciacca, the 1831 eruption formed the short-lived Ferdinandea Island that represents the only Italian volcano active in historical times currently almost completely unknown and not yet monitored. Moreover, most of the Sicily Channel seismicity is concentrated along a broad NS belt extending from the Graham Bank to Lampedusa Island. In 2012, the Istituto Nazionale di Geofisica e Vulcanologia (INGV carried out a multidisciplinary oceanographic cruise, named “Ferdinandea 2012”, the preliminary results of which represent the aim of this paper. The cruise goal was the mapping of the morpho-structural features of some submarine volcanic centres located in the northwestern side of the Sicily Channel and the temporary recording of their seismic and degassing activity. During the cruise, three OBS/Hs (ocean bottom seismometer with hydrophone were deployed near the Graham, Nerita and Terribile submarine banks. During the following 9 months they have recorded several seismo-acoustic signals produced by both tectonic and volcanic sources. A high-resolution bathymetric survey was achieved on the Graham Bank and on the surrounding submarine volcanic centres. A widespread and voluminous gas bubbles emission was observed by both multibeam sonar echoes and a ROV (remotely operated vehicle along the NW side of the Graham Bank, where gas and seafloor samples were also collected.

  17. Compartment Syndrome of the Hand: A Little Thought about Diagnosis (United States)

    Reichman, Eric F.


    Compartment syndrome of the forearm is a well described entity but there have been relatively few case reports in the emergency medicine literature of hand compartment syndromes (HCS). Prompt recognition and treatment of this potential limb threat are essential to minimize morbidity and mortality. Presented is a case of a documented hand compartment syndrome following a motor vehicle collision. PMID:27293917

  18. Lower limb compartment syndrome as a complication of radical hysterectomy


    Oman, Sarah A.; Schwarz, Daniel; Muntz, Howard G.


    Highlights ? Compartment syndrome is a rare complication of prolonged lithotomy position. ? We report a case of compartment syndrome complicating radical hysterectomy. ? Prompt diagnosis is crucial to reduce morbidity from compartment syndrome. ? Awareness of this complication allows surgeons to address modifiable risk factors.

  19. The compartment syndrome: is the intra-compartment pressure a reliable indicator for early diagnosis? (United States)

    Nudel, Iftah; Dorfmann, Luis; deBotton, Gal


    Compartment syndrome (CS) occurs when the pressure in an enclosed compartment increases due to tissue swelling or internal bleeding. As the intra-compartmental pressure (ICP) builds up, the blood flow to the tissue or the organ is compromised, resulting in ischemia, necrosis and damage to the nerves and other tissues. At the present there are no established diagnostic procedures, and clinical observations such as pain, paralysis and even compartment pressure monitoring are an unreliable determinant of the presence of the syndrome. Late diagnosis may result in fasciotomy, neurological dysfunctions, amputation and even death. Focusing on the frequently occurring CS of the lower leg, this work is aimed toward introducing a coherent, mechanically motivated analysis of the disease within the framework of poroelasticity. The fascia enclosing the compartment is treated as an inextensible and impermeable layer, and the tissue inside the compartment is represented as a fully saturated poroelastic solid. The model quantitatively predicts the highly non-uniform ICP buildup as a function of both time and location. These findings, which are in good agreement with clinical observations reported in the literature, shed light on the difficulties associated with the identification of the syndrome and may assist in improved diagnostic procedures. © The authors 2016. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

  20. A cadaver study into the number of fasciotomies required to decompress the anterior compartment in forearm compartment syndrome. (United States)

    Benamran, Lionel; Masquelet, Alain Charles


    There is no typical approach for decompression of forearm compartment syndrome, due to contradictory considerations regarding the characteristics of forearm anterior compartment deep fascia. The main purpose of this study was to determine how many fasciae should be opened to fully decompress the forearm anterior compartment. Further, the compliance of the deep anterior compartment was also investigated, to strengthen our results. An experimental study of a laboratory model of acute forearm compartment syndrome was performed. A deep forearm injection of egg white was undertaken to create an acute forearm compartment syndrome in sixteen non-embalmed human forearms from six male and two female donors. The pressure in the superficial and deep anterior compartments was recorded four times, both before and after each fasciotomy and the compliance of the deep anterior compartment was calculated for each step. The first incision of the superficial lamina of the deep fascia was not sufficient to decrease the elevated compartment pressure in the superficial and deep anterior compartments. Whereas the pressures decreased to near-baseline levels, following the fasciotomy of the intermuscular septum observed posterior to the flexor carpi radialis. The last incision of the deep lamina of the deep anterior fascia had no noticeable impact. These observations supported the hypothesis of high compliance of the deep anterior compartment. Two successive incisions were necessary to decompress the anterior compartment: the incision of the superficial lamina of the deep fascia and the incision of the intermuscular septum.

  1. Nuclear reactor neutron shielding (United States)

    Speaker, Daniel P; Neeley, Gary W; Inman, James B


    A nuclear reactor includes a reactor pressure vessel and a nuclear reactor core comprising fissile material disposed in a lower portion of the reactor pressure vessel. The lower portion of the reactor pressure vessel is disposed in a reactor cavity. An annular neutron stop is located at an elevation above the uppermost elevation of the nuclear reactor core. The annular neutron stop comprises neutron absorbing material filling an annular gap between the reactor pressure vessel and the wall of the reactor cavity. The annular neutron stop may comprise an outer neutron stop ring attached to the wall of the reactor cavity, and an inner neutron stop ring attached to the reactor pressure vessel. An excore instrument guide tube penetrates through the annular neutron stop, and a neutron plug comprising neutron absorbing material is disposed in the tube at the penetration through the neutron stop.

  2. Ultrasonic Apparatus and Method to Assess Compartment Syndrome (United States)

    Yost, William T. (Inventor); Ueno, Toshiaki (Inventor); Hargens, Alan R. (Inventor)


    A process and apparatus for measuring pressure buildup in a body compartment that encases muscular tissue. The method includes assessing the body compartment configuration and identifying the effect of pulsatible components on compartment dimensions and muscle tissue characteristics. This process is used in preventing tissue necrosis, and in decisions of whether to perform surgery on the body compartment for prevention of Compartment Syndrome. An apparatus is used for measuring pressure build-up in the body compartment having components for imparting ultrasonic waves such as a transducer, placing the transducer to impart the ultrasonic waves, capturing the imparted ultrasonic waves, mathematically manipulating the captured ultrasonic waves and categorizing pressure build-up in the body compartment from the mathematical manipulations.

  3. Acute compartment syndrome of forearm and hand (United States)

    Chandraprakasam, T.; Kumar, R. Ashok


    The diagnosis and treatment of the acute compartment syndrome is of paramount importance. Unless the viscious cycle is intervened at an appropriately early time it will result in irreversible damage leading to disability. In this review article we are discussing the basic pathophysiological process through which the various aetiological factors causing increased compartmental pressure lead to the progressive death of muscles and nerves. We also discuss the various clinical features that aid in the diagnosis and the role of intracompartmental pressure measurements. Finally we hope to ascertain the basic principles and the surgical techniques for treating this condition effectively. PMID:22022031

  4. [Intraabdominal hypertension and abdominal compartment syndrome

    DEFF Research Database (Denmark)

    Sonne, M.; Hilligsø, Jens Georg


    Intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare conditions with high mortality. IAH is an intraabdominal pressure (IAP) above 12 mmHg and ACS an IAP above 20 mmHg with evidence of organ dysfunction. IAP is measured indirectly via the bladder or stomach. Various...... medical and surgical conditions increase the intraabdominal volume. When the content exceeds the compliance of the abdominal wall, the IAP rises. Increased IAP affects the functioning of the brain, lungs, circulation, kidneys, and bowel. The treatment of ACS is a reduction of IAP Udgivelsesdato: 2008/2/11...

  5. Acute compartment syndrome of forearm and hand

    Directory of Open Access Journals (Sweden)

    T Chandraprakasam


    Full Text Available The diagnosis and treatment of the acute compartment syndrome is of paramount importance. Unless the viscious cycle is intervened at an appropriately early time it will result in irreversible damage leading to disability. In this review article we are discussing the basic pathophysiological process through which the various aetiological factors causing increased compartmental pressure lead to the progressive death of muscles and nerves. We also discuss the various clinical features that aid in the diagnosis and the role of intracompartmental pressure measurements. Finally we hope to ascertain the basic principles and the surgical techniques for treating this condition effectively.

  6. Acute compartment syndrome of forearm and hand. (United States)

    Chandraprakasam, T; Kumar, R Ashok


    The diagnosis and treatment of the acute compartment syndrome is of paramount importance. Unless the viscious cycle is intervened at an appropriately early time it will result in irreversible damage leading to disability. In this review article we are discussing the basic pathophysiological process through which the various aetiological factors causing increased compartmental pressure lead to the progressive death of muscles and nerves. We also discuss the various clinical features that aid in the diagnosis and the role of intracompartmental pressure measurements. Finally we hope to ascertain the basic principles and the surgical techniques for treating this condition effectively.

  7. Supraspinatus and infraspinatus compartment syndrome following scapular fracture. (United States)

    Kenny, Ryan M; Beiser, Christopher W; Patel, Arun


    Acute compartment syndrome occurs when pressure within a confined fascial space rises to a level impairing microvascular perfusion to surrounding tissues.[1234567] The majority of the reported literature is based on lower extremity compartment syndrome, but any muscle group within an osteofascial compartment has the potential to develop compartment syndrome. We report a case of a 64-year-old male who developed an acute compartment syndrome of both the supraspinatus and infraspinatus after sustaining a severely comminuted scapula fracture. Diagnosis of compartment syndrome was made after intracompartmental pressure measurements of the supraspinatus and infraspinatus revealed pressures within 30 mmHg of the diastolic blood pressure, prompting emergency decompressive fasciotomy. At final follow-up, the examination revealed full shoulder strength with near-full range of motion. There were no signs of sequelae from compartment syndrome at any point. Few case reports describe compartment syndrome of the periscapular fascial compartments. However, these cases were either retrospectively diagnosed[89] or diagnosed via magnetic resonance imaging (MRI) findings and lab values.[910] Surgical management of acute compartment syndrome of the supraspinatus has been reported in only one other case.[10] To our knowledge, we report the only case of a patient with acute compartment syndrome of both the supraspinatus and infraspinatus compartments treated with emergent decompressive fasciotomy. Due to the devastating complications and functional loss of a missed diagnosis of compartment syndrome, a high index of clinical suspicion for developing compartment syndrome must be maintained in every fracture setting, regardless of anatomic location or rarity of reported cases.

  8. What is the clinical relevance of different lung compartments? (United States)


    The lung consists of at least seven compartments with relevance to immune reactions. Compartment 1 - the bronchoalveolar lavage (BAL), which represents the cells of the bronchoalveolar space: From a diagnostic point of view the bronchoalveolar space is the most important because it is easily accessible in laboratory animals, as well as in patients, using BAL. Although this technique has been used for several decades it is still unclear to what extent the BAL represents changes in other lung compartments. Compartment 2 - bronchus-associated lymphoid tissue (BALT): In the healthy, BALT can be found only in childhood. The role of BALT in the development of the mucosal immunity of the pulmonary surfaces has not yet been resolved. However, it might be an important tool for inhalative vaccination strategies. Compartment 3 - conducting airway mucosa: A third compartment is the bronchial epithelium and the submucosa, which both contain a distinct pool of leukocytes (e.g. intraepithelial lymphocytes, IEL). This again is also accessible via bronchoscopy. Compartment 4 - draining lymph nodes/Compartment 5 - lung parenchyma: Transbronchial biopsies are more difficult to perform but provide access to two additional compartments - lymph nodes with the draining lymphatics and lung parenchyma, which roughly means "interstitial" lung tissue. Compartment 6 - the intravascular leukocyte pool: The intravascular compartment lies between the systemic circulation and inflamed lung compartments. Compartment 7 - periarterial space: Finally, there is a unique, lung-specific space around the pulmonary arteries which contains blood and lymph capillaries. There are indications that this "periarterial space" may be involved in the pulmonary host defense. All these compartments are connected but the functional network is not yet fully understood. A better knowledge of the complex interactions could improve diagnosis and therapy, or enable preventive approaches of local immunization. PMID

  9. What is the clinical relevance of different lung compartments?

    Directory of Open Access Journals (Sweden)

    Pabst Reinhard


    Full Text Available Abstract The lung consists of at least seven compartments with relevance to immune reactions. Compartment 1 – the bronchoalveolar lavage (BAL, which represents the cells of the bronchoalveolar space: From a diagnostic point of view the bronchoalveolar space is the most important because it is easily accessible in laboratory animals, as well as in patients, using BAL. Although this technique has been used for several decades it is still unclear to what extent the BAL represents changes in other lung compartments. Compartment 2 – bronchus-associated lymphoid tissue (BALT: In the healthy, BALT can be found only in childhood. The role of BALT in the development of the mucosal immunity of the pulmonary surfaces has not yet been resolved. However, it might be an important tool for inhalative vaccination strategies. Compartment 3 – conducting airway mucosa: A third compartment is the bronchial epithelium and the submucosa, which both contain a distinct pool of leukocytes (e.g. intraepithelial lymphocytes, IEL. This again is also accessible via bronchoscopy. Compartment 4 – draining lymph nodes/Compartment 5 – lung parenchyma: Transbronchial biopsies are more difficult to perform but provide access to two additional compartments – lymph nodes with the draining lymphatics and lung parenchyma, which roughly means "interstitial" lung tissue. Compartment 6 – the intravascular leukocyte pool: The intravascular compartment lies between the systemic circulation and inflamed lung compartments. Compartment 7 – periarterial space: Finally, there is a unique, lung-specific space around the pulmonary arteries which contains blood and lymph capillaries. There are indications that this "periarterial space" may be involved in the pulmonary host defense. All these compartments are connected but the functional network is not yet fully understood. A better knowledge of the complex interactions could improve diagnosis and therapy, or enable preventive approaches

  10. Acute atraumatic compartment syndrome in an athlete: a case report. (United States)

    Stollsteimer, G T; Shelton, W R


    To present the case of a college football player with acute, atraumatic, exercise-induced compartment syndrome in the leg. Acute, atraumatic, exercise-induced compartment syndrome is an infrequently reported cause of leg pain in the athlete. If left untreated, acute compartment syndrome can cause muscle necrosis. Chronic exertional compartment syndrome, medial tibial syndrome, stress fracture. Treatment consists of compartment fasciotomy. This previously healthy, but unconditioned, athlete developed severe anterolateral left leg pain after two days of fall practice in which he was unable to run a mile in 7.5 minutes. Physical examination by the team physician revealed acute compartment syndrome, and an emergency anterolateral compartment fasciotomy was performed. Second-look débridement performed 48 hours later revealed no significant change in the necrotic appearance of the anterior compartment soft tissue. Therefore, the dead muscle was completely débrided, and a free-flap latissumus dorsi graft was used for coverage of the wound. With recovery, strength returned to normal in the lateral compartment but remained 0/5 in the anterior compartment. The patient had persistent sensory loss in the distributions of the superficial and deep peroneal nerves. Although much less common than the more frequent causes of leg pain (ie, chronic exertional compartment syndrome, medial tibial syndrome, stress fracture), acute compartment syndrome is potentially more devastating. When the increased intracompartmental pressure within a closed tissue space exceeds capillary perfusion pressure, tissue perfusion is decreased, the soft tissue becomes ischemic, and cells die. The most important clinical diagnostic signs of compartment syndrome are pain with passive stretching of the compartment and pain out of proportion to the results of the physical examination.

  11. Compartment model DETRA for Windows; Kompartmenttimalli DETRA Windows-kaeyttoeympaeristoeae varten

    Energy Technology Data Exchange (ETDEWEB)

    Suolanen, V.; Ilvonen, M. [VTT Energy, Espoo (Finland)


    The computer code DETRA is a generic tool for environmental transfer analyses of radioactive or stable substances. The code has been applied for various purposes, mainly problems related to the biospheric transfer of radionuclides both in safety analyses of disposal of nuclear wastes and in consideration of foodchain exposure pathways in the analyses of off-site consequences of reactor accidents. The first computer code version for Windows interface environment of the modernized DETRA compartment model is developed in the study. As the model needs quite a large number of input data for specifying a calculation case, different segments of the input file (nuclide chains, compartments, time grid, source term, initial values, applications for multi-sequence calculations, printout specifications) are presented in their own window displays. The basic character of the code allows the user to specify the compartment model structure suitable for each considered environmental transport problem individually. The transport of radionuclides can be considered in several cases: water courses and related food chains, soil surface layers, food chains and general food stuffs, body burden analyses, etc. The pre-fined and saved input files for different areas of environmental, transport problems are also available for the user. The starting point for the analysis can be deposition on ground, or source term of radionuclides from e.g. surface soil into a recipient can be considered by the code as well.

  12. Raised compartment pressures are frequently observed with tibial shaft fractures despite the absence of compartment syndrome: A prospective cohort study. (United States)

    Ho, Kelvin Lor Kah; Sing, Nicholas Yeoh Ching; Wong, Khai Phang; Huat, Andy Wee Teck


    To measure the intracompartmental pressures surrounding tibial fractures not exhibiting any clinical evidence of compartment syndrome. Our hypothesis was that pressures often exceed the recommended threshold of fasciotomy despite the absence of compartment syndrome, and hence diagnosis based on pressure measurements alone is unreliable. Thirteen consecutive patients with closed tibial shaft fractures without clinical suspicion of compartment syndrome, and who were planned for intramedullary nailing, were prospectively enrolled. Compartment pressures ( P) in all four compartments of the affected leg were measured at the start of surgery and immediately after tibial reaming, and differential pressures (delta P) were calculated based on the diastolic blood pressure prior to induction of anaesthesia. No patients required reoperation in the post-operative period, as a result of an undiagnosed compartment syndrome. Using commonly quoted threshold pressure criteria, 62% (using P > 30 mmHg) and 23% of patients (using delta P compartment syndrome. We conclude that raised compartment pressures are frequently seen in patients with tibial shaft fractures; but in most cases, it does not equate to the presence of compartment syndrome. Diagnosis of compartment syndrome based on intracompartmental pressure measurements alone may result in unnecessary fasciotomies in a sizeable number of patients. Compartment syndrome remains a clinical diagnosis, and one which always needs to be considered when managing tibial fractures.

  13. Functional dissociation of the basolateral transcytotic compartment from the apical phago-lysosomal compartment in human osteoclasts. (United States)

    Meagher, James; Zellweger, René; Filgueira, Luis


    Tartrate-resistant acid phosphatase (TRAP) is essential for elimination of Staphylococcus aureus, the main infectious agent responsible for osteomyelitis. This in vitro study investigated uptake and processing of fluorescence-labeled S. aureus by human osteoclasts and dendritic cells. The cells were stained for TRAP and the acidic compartment using a fluorescence-based protocol. In dendritic cells, TRAP and bacteria were colocalized. In osteoclasts, there was no colocalization of bacteria, TRAP, or the acidic compartment, indicating that there are three distinct vesicular compartments: the apical phago-lysosomal compartment, the basal secretory compartment, and the basolateral transcytotic compartment. Dissociation of the TRAP-containing transcytotic vesicles from the apical phago-lysosomal compartment may restrain osteoclasts from eliminating S. aureus.

  14. Gluteal Compartment Syndrome After Prolonged Immobilisation

    Directory of Open Access Journals (Sweden)

    H.L. Liu


    Full Text Available Muscles in the gluteal region are confined by distinct fascial attachments which can potentially result in compartment syndrome. A 74-year-old chronic drinker was admitted to the medical ward after being found drunk on the street. He noticed acute painful swelling of the right side of his buttock the following morning and recalled a slip and fall prior to his blackout. The whole right half of the buttock was tense with erythematous overlying skin. Examination revealed sciatic nerve palsy and myoglobinuria. Emergency fasciotomy and debridement were performed. Intra-operative pressure measurement confirmed a grossly elevated intra-compartmental pressure. Gluteal compartment syndrome is an extremely rare condition and has only been scantily documented previously in case reports. Early diagnosis is crucial but delay recognition is common from lack of knowledge of the condition and readily results in permanent sciatic nerve injury and acute renal shutdown from myoglobinuria. Awareness of the condition, early diagnosis and prompt exploration provide the only chance of avoiding these devastating consequences. Acute swelling diffusely affecting the whole or one side of the buttock, a history of trauma and prolonged local pressure impingement associated with pain out of proportion to the clinical signs should raise a suspicion of this rare condition.

  15. [Medical-physiological characteristics of combat training of nuclear-power submarine crews]. (United States)

    Dovgusha, V V; Myznikov, I L; Shalabodov, S A; Bumaĭ, O K


    The article presents an observe of general questions of peculiarities of military-professional activity of submarine staff These questions are defining value in ideology of medical supply of submarine troops of NAVY in now-days conditions. The article also presents the statistics of morbidity in long termed sails for last forty years, it's dynamics by different categories of sail staff, on different stages of combat training activity in dependence of perioditation of work cycle of submarine staff The authors have examined modern condition of medical supply of submarines; have presented statistics of quality indexes of health of submarine staff The authors have formed main problems of medical supply of submarines and have proposed ways of their solving on modern stage.

  16. Losses in armoured three-phase submarine cables

    DEFF Research Database (Denmark)

    Ebdrup, Thomas; Silva, Filipe Miguel Faria da; Bak, Claus Leth


    increases the losses in armoured cables compared to unarmoured cables. In this paper a thorough state of the art analysis is conducted on armour losses in three-phase armoured submarine power cables. The analysis shows that the IEC 60287-1-1 standard overestimates the armour losses which lead...... to the installation of cables with excessive phase conductor cross section. This paper also presents an example of the potential economic benefits of having a better knowledge of the losses introduced by the armour.......The number of offshore wind farms will keep increasing in the future as a part of the shift towards a CO2 free energy production. The energy harvested from the wind farm must be brought to shore, which is often done by using a three-phase armoured submarine power cable. The use of an armour...

  17. Stresses in a submarine topography under ocean waves

    Energy Technology Data Exchange (ETDEWEB)

    Mei, C.C.; McTigue, D.F.


    The problem of submarine slope stability is of interest to both offshore engineering and geology. In an uneven topography, the weight above a horizontal plane induces two-dimensional variation in the static stress field. The action of wave pressure, which changes with depth, further introduces excess pore pressure and dynamic stresses in the sea bottom. In the present paper, we combine a simple analytical theory for the static stress by the present authors, and the recent solution by Mei and Foda for wave-induced stresses in a plane poro-elastic sea bed to account for mild bottom slope and wave shoaling, to obtain the effective stress field in a submarine topography under sea waves. Sample results are given for a ridge and a canyon. In particular the dynamic pore pressure and the combined static and dynamic effective stresses are presented. 10 references, 11 figures.

  18. Stresses in a submarine topography under ocean waves

    Energy Technology Data Exchange (ETDEWEB)

    Mei, C.C.; McTigue, D.F.


    The problem of submarine slope stability is of interest to both offshore engineering and geology. In an uneven topography, the weight above a horizontal plane induces two-dimensional variation in the static stress field. The action of wave pressure, which changes with depth, further introduces excess pore pressure and dynamic stresses in the sea bottom. In the present paper, we combine a simple analytical theory for the static stress by the present authors, and the recent solution by Mei and Foda for wave-induced stresses in a plane poro-elastic sea bed to account for mild bottom slope and wave shoaling, and obtain the effective stress field in a submarine topography under sea waves. Sample results are given for a ridge and a canyon. In particular, the dynamic pore pressure and the combined static and dynamic effective stresses are presented.

  19. Intramuscular compartment pressure measurement in chronic exertional compartment syndrome: new and improved diagnostic criteria. (United States)

    Roscoe, David; Roberts, Andrew J; Hulse, David


    Patients with chronic exertional compartment syndrome (CECS) have pain during exercise that subsides with rest. Diagnosis is usually confirmed by intramuscular compartment pressure (IMCP) measurement. Controversy exists regarding the accuracy of existing diagnostic criteria. (1) To compare dynamic IMCP measurement and anthropometric factors between patients with CECS and asymptomatic controls and (2) to establish the diagnostic utility of dynamic IMCP measurement. Cohort study (diagnosis); Level of evidence, 2. A total of 40 men aged 21 to 40 years were included in the study: 20 with symptoms of CECS of the anterior compartment and 20 asymptomatic controls. Diagnoses other than CECS were excluded with rigorous inclusion criteria and magnetic resonance imaging. The IMCP was measured continuously before, during, and after participants exercised on a treadmill, wearing identical footwear and carrying a 15-kg load. Pain experienced by study subjects increased incrementally as the study progressed (P compartment IMCP is elevated immediately upon standing at rest in subjects with CECS. In patients with symptoms consistent with CECS, diagnostic utility of IMCP measurement is improved when measured continuously during exercise. A cutoff of 105 mm Hg in phase 2 provides better diagnostic accuracy than do the Pedowitz criteria of 30 mm Hg and 20 mm Hg at 1 and 5 minutes after exercise, respectively. © 2014 The Author(s).

  20. Improving Situational Awareness on Submarines Using Augmented Reality (United States)


    COSO ) are several pages of guidance for the evolution available to the watch officer for reference. There are also Operating Procedures that the watch...officer must follow to ensure the safe ascent to PD. The COSOs are specific to the each CO. The OPs are specific to a class of submarine. The...evolution in the framework described above can provide valuable insight to the capabilities of the proposed system. This of course is a hypothetical

  1. Analysis of SSN 688 Class Submarine Maintenance Delays (United States)


    errors an in-depth analysis into the job-level maintenance is required which is outside the scope of this analysis. 25 2. New Work Causes Late...attempting to determine the cause of this trend. Finally, this thesis proposes a solution to the systematic underestimation of availability durations by...illustrating the inherent error in the current equation and providing a notional equation to remove that error . 14. SUBJECT TERMS Submarine

  2. Submarine Pressure Hull Collapse Considering Corrosion and Penetrations (United States)


    corrosion. Des valeurs de la pression d’écrasement sont calculées pour les diverses dimensions de la zone de corrosion, et ce, dans les cas de présence ou...Research & Development Canada DRDIM Director Research and Development Knowledge and Information Management OOC Out-of-circularity R&D Research...Support SLA (Mr. John Porter) 1 Project Manager , Submarine Scientific Support SLA (LCdr Wade Temple) 9 TOTAL LIST PART I LIST PART II: External

  3. Europe’s Grand Canyon: Nazaré submarine canyon


    Tyler, P.; Amaro, T.; Arzola, R.; Cunha; Stigter, H. de; Gooday, A.; Huvenne, V.; Ingels, J; Kiriakoulakis, K; Lastras, G.; Masson, D.; Oliveira, A.; Pattenden, A.; Vanreusel, A.; van Weering, T.


    The Nazare submarine canyon extends similar to 210 km westward from the coast of Portugal, down to a water depth of > 4300 m. The considerable habitat heterogeneity found throughout the canyon is affected by strong currents and high turbidity, especially in the upper parts of the canyon. The canyon morphology comprises steep slopes, scarps, terraces, and overhangs, and a deeply incised thalweg is found in the lower part of the canyon. The seabed within the canyon is composed of varying propor...

  4. Role of Repeat Muscle Compartment Pressure Measurements in Chronic Exertional Compartment Syndrome of the Lower Leg (United States)

    van Zantvoort, Aniek P. M.; de Bruijn, Johan A.; Winkes, Michiel B.; Hoogeveen, Adwin R.; Teijink, Joep A. W.; Scheltinga, Marc R.


    Background: The diagnostic gold standard for diagnosing chronic exertional compartment syndrome (CECS) is a dynamic intracompartmental pressure (ICP) measurement of the muscle. The potential role of a repeat ICP (re-ICP) measurement in patients with persistent lower leg symptoms after surgical decompression or with ongoing symptoms after an earlier normal ICP is unknown. Purpose: To study whether re-ICP measurements in patients with persistent CECS-like symptoms of the lower leg may contribute to the diagnosis of CECS after both surgical decompression and a previously normal ICP measurement. Study Design: Case series; Level of evidence, 4. Methods: Charts of patients who underwent re-ICP measurement of lower leg compartments (anterior [ant], deep posterior [dp], and/or lateral [lat] compartments) between 2001 and 2013 were retrospectively studied. CECS was diagnosed on the basis of generally accepted cutoff pressures for newly onset CECS (Pedowitz criteria: ICP at rest ≥15 mmHg, ≥30 mmHg after 1 minute, or ≥20 mmHg 5 minutes after a provocative test). Factors predicting recurrent CECS after surgery or after a previously normal ICP measurement were analyzed. Results: A total of 1714 ICP measurements were taken in 1513 patients with suspected CECS over a 13-year observation period. In all, 201 (12%) tests were re-ICP measurements for persistent lower leg symptoms. Based on the proposed ICP cutoff values, CECS recurrence was diagnosed in 16 of 62 previously operated compartments (recurrence rate, 26%; 53 patients [64% female]; median age, 24 years; age range, 15-78 years). Recurrence rates were not different among the 3 lower leg CECS compartments (ant-CECS, 17%; dp-CECS, 33%; lat-CECS, 30%; χ2 = 1.928, P = .381). Sex (χ2 = 0.058, P = .810), age (U = 378, z = 1.840, P = .066), bilaterality (χ2 = 0.019, P = .889), and prefasciotomy ICP did not predict recurrence. Re-ICP measurements evaluating 20 compartments with previously normal ICP measurements (15

  5. Submarine and Autonomous Vessel Proliferation: Implications for Future Strategic Stability at Sea (United States)


    replace the Ohio- class SSBN and Virginia -class SSN to replace the Los Angeles class attack submarine. Although more sophisticated than their...predecessors and with some modifications to demands of the post-Cold War era and (in the Virginia class) an emphasis on littoral conflict, these purchases...Congressional Research Service analyst Amy Woolf observes: “With few submarines in the fleet, the Navy would have to reduce the number of submarines on

  6. The future of the ballistic missile submarine force in the Russian nuclear triad


    Lesiw, Richard T.


    Approved for public release; distribution is unlimited This thesis analyzes the current status of the Russian Federation's ballistic missile submarine force. It reviews the history of the ballistic missile submarine force, its current status, and the implementation of plans currently in progress and as well as the advantages and disadvantages of maintaining a ballistic missile submarine force. This thesis also assesses the other two legs of the nuclear triad - the intercontinental balli...

  7. Gender Integration on U.S. Navy Submarines: Views of the First Wave (United States)


    submarines is to perform seek-and-destroy missions on enemy ships and submarines, conduct surveillance and reconnaissance, provide covert troop insertion...not only the missile payload they were designed to carry but also extended periods at sea without resupply. In terms of berthing and sanitary ...officer berthing and sanitary 28 facilities on board Ohio class submarines, however, no significant modifications would be necessary in order to

  8. Introduction to the special issue on submarine geohazard records and potential seafloor instability

    Directory of Open Access Journals (Sweden)

    Song-Chuen Chen Jia-Jyun Dong


    Full Text Available Submarine landslides frequently occur in passive continental margins or active margins (Hampton et al. 1996; Wynn et al. 2000; Mienert et al. 2002; Korup et al. 2007; Twichell et al. 2009; Cukur et al. 2016. Submarine landslides have been studied extensively not only for scientific research but also for submarine geohazards. Submarine landslides could jeopardize marine infrastructures, such as offshore drilling platforms or submarine telecommunication cables, and could even trigger disastrous tsunamis (Bondevik et al. 2005; Harbitz et al. 2006; Hornbach et al. 2007, 2008; Hsu et al. 2008; Su et al. 2012; Tappin et al. 2014; Li et al. 2015. For instance, one disastrous tsunami hitting the coastal area of southwestern Taiwan in 1781 or 1782 was reported (Chen 1830; Hsu 1983; the tsunami event was probably generated by submarine landslides in the offshore area of southwestern Taiwan (Li et al. 2015. Moreover, several submarine landslides triggered by the 2006 Pingtung earthquake have induced turbidity currents off southwest Taiwan and destroyed about 14 submarine telecommunication cables off SW Taiwan (Hsu et al. 2008. The area of southwest Taiwan currently has a dense population (more than 3 million people in total, one deep-water Kaohsiung Port, several tanks of liquefied natural gas and a nuclear power plant on the coast (Fig. 1. Numerous submarine telecommunication cables exist off SW Taiwan. If a considerable tsunami event would hit again the costal area of SW Taiwan, the damage could very serious. Likewise, there are two nuclear power plants on the coast of northern Taiwan (Fig. 2, and the population in northern Taiwan has more than 10 million people. Submarine telecommunication cables also exist off northern Taiwan. In any case, it is important to understand the status of seafloor stability in the offshore areas of SW and NE Taiwan. For that, this special issue of submarine geohazard records and potential seafloor instability is aimed to

  9. Fuel-cell-propelled submarine-tanker-system study

    Energy Technology Data Exchange (ETDEWEB)

    Court, K E; Kumm, W H; O' Callaghan, J E


    This report provides a systems analysis of a commercial Arctic Ocean submarine tanker system to carry fossil energy to markets. The submarine is to be propelled by a modular Phosphoric Acid Fuel Cell system. The power level is 20 Megawatts. The DOE developed electric utility type fuel cell will be fueled with methanol. Oxidant will be provided from a liquid oxygen tank carried onboard. The twin screw submarine tanker design is sized at 165,000 deadweight tons and the study includes costs and an economic analysis of the transport system of 6 ships. The route will be under the polar icecap from a loading terminal located off Prudhoe Bay, Alaska to a transshipment facility postulated to be in a Norwegian fjord. The system throughput of the gas-fed methanol cargo will be 450,000 barrels per day. The total delivered cost of the methanol including well head purchase price of natural gas, methanol production, and shipping would be $25/bbl from Alaska to the US East Coast. Of this, the shipping cost is $6.80/bbl. All costs in 1981 dollars.

  10. Estimating the empirical probability of submarine landslide occurrence (United States)

    Geist, Eric L.; Parsons, Thomas E.; Mosher, David C.; Shipp, Craig; Moscardelli, Lorena; Chaytor, Jason D.; Baxter, Christopher D. P.; Lee, Homa J.; Urgeles, Roger


    The empirical probability for the occurrence of submarine landslides at a given location can be estimated from age dates of past landslides. In this study, tools developed to estimate earthquake probability from paleoseismic horizons are adapted to estimate submarine landslide probability. In both types of estimates, one has to account for the uncertainty associated with age-dating individual events as well as the open time intervals before and after the observed sequence of landslides. For observed sequences of submarine landslides, we typically only have the age date of the youngest event and possibly of a seismic horizon that lies below the oldest event in a landslide sequence. We use an empirical Bayes analysis based on the Poisson-Gamma conjugate prior model specifically applied to the landslide probability problem. This model assumes that landslide events as imaged in geophysical data are independent and occur in time according to a Poisson distribution characterized by a rate parameter λ. With this method, we are able to estimate the most likely value of λ and, importantly, the range of uncertainty in this estimate. Examples considered include landslide sequences observed in the Santa Barbara Channel, California, and in Port Valdez, Alaska. We confirm that given the uncertainties of age dating that landslide complexes can be treated as single events by performing statistical test of age dates representing the main failure episode of the Holocene Storegga landslide complex.

  11. Pockmark morphology and turbulent buoyant plumes at a submarine spring (United States)

    Buongiorno Nardelli, B.; Budillon, F.; Watteaux, R.; Ciccone, F.; Conforti, A.; De Falco, G.; Di Martino, G.; Innangi, S.; Tonielli, R.; Iudicone, D.


    The input flow of groundwater from the seabed to the coastal ocean, known as Submarine Groundwater Discharge (SGD), has been only recently recognized as an important component of continental margin systems. It potentially impacts physical, chemical and biological marine dynamics. Independently of its specific nature (seepage, submarine springs, etc.) or fluid chemical composition, a SGD is generally characterized by low flow rates, hence making its detection and quantification very difficult, and explaining why it has been somewhat neglected by the scientific community for a long time. Along with the growing interest for SGDs emerged the need for in-situ observations in order to characterize in details how these SGDs behave. In this work, we describe the morphology of a pockmark field, detected in the Southern Tyrrhenian Sea (Mediterranean Sea), and provide observational evidences of the presence of active submarine springs over the coastal shelf area. We describe the effect of the fluid seeps on the water column stratification close to the main plumes and in the neighbouring areas, providing quantitative estimates of the intensity of the turbulent mixing and discussing their potential impact on the seabed morphology and pockmark formation in the context of turbulent buoyant plumes analytical modelling.

  12. Long-term eruptive activity at a submarine arc volcano. (United States)

    Embley, Robert W; Chadwick, William W; Baker, Edward T; Butterfield, David A; Resing, Joseph A; de Ronde, Cornel E J; Tunnicliffe, Verena; Lupton, John E; Juniper, S Kim; Rubin, Kenneth H; Stern, Robert J; Lebon, Geoffrey T; Nakamura, Ko-ichi; Merle, Susan G; Hein, James R; Wiens, Douglas A; Tamura, Yoshihiko


    Three-quarters of the Earth's volcanic activity is submarine, located mostly along the mid-ocean ridges, with the remainder along intraoceanic arcs and hotspots at depths varying from greater than 4,000 m to near the sea surface. Most observations and sampling of submarine eruptions have been indirect, made from surface vessels or made after the fact. We describe here direct observations and sampling of an eruption at a submarine arc volcano named NW Rota-1, located 60 km northwest of the island of Rota (Commonwealth of the Northern Mariana Islands). We observed a pulsating plume permeated with droplets of molten sulphur disgorging volcanic ash and lapilli from a 15-m diameter pit in March 2004 and again in October 2005 near the summit of the volcano at a water depth of 555 m (depth in 2004). A turbid layer found on the flanks of the volcano (in 2004) at depths from 700 m to more than 1,400 m was probably formed by mass-wasting events related to the eruption. Long-term eruptive activity has produced an unusual chemical environment and a very unstable benthic habitat exploited by only a few mobile decapod species. Such conditions are perhaps distinctive of active arc and hotspot volcanoes.

  13. An experimental study on crib fires in a closed compartment

    Directory of Open Access Journals (Sweden)

    Dhurandher Bhisham Kumar


    Full Text Available An experimental investigation on burning behavior of fire in closed compartments is presented. Fire experiments were performed in a closed compartment of interior dimensions 4 × 4 × 4 m (length × width × height with ply board cribs as fire source. The parameters including the gas temperature, mass loss rate, heat flux, flame temperature, and compartment pressure were measured during the experiments. Experimental results indicated that the providing sudden ventilation to the closed compartment had great influence on the behavior of fire. The mass loss rate of the burning crib increased by 150% due to sudden ventilation which results in the increase in heat release rate by 198 kW. From the perspective of total heat flux, compartment pressure, and gas temperatures closed compartment with sudden ventilation were more hazardous.

  14. Scientific Ocean Drilling to Assess Submarine Geohazards along European Margins (United States)

    Ask, M. V.; Camerlenghi, A.; Kopf, A.; Morgan, J. K.; Ocean DrillingSeismic Hazard, P. E.


    Submarine geohazards are some of the most devastating natural events in terms of lives lost and economic impact. Earthquakes pose a big threat to society and infrastructure, but the understanding of their episodic generation is incomplete. Tsunamis are known for their potential of striking coastlines world-wide. Other geohazards originating below the sea surface are equally dangerous for undersea structures and the coastal population: submarine landslides and volcanic islands collapse with little warning and devastating consequences. The European scientific community has a strong focus on geohazards along European and nearby continental margins, especially given their high population densities, and long historic and prehistoric record of hazardous events. For example, the Mediterranean is surrounded by very densely-populated coastline and is the World's leading holiday destination, receiving up 30% of global tourism. In addition, its seafloor is criss-crossed by hydrocarbon pipelines and telecommunication cables. However, the governing processes and recurrence intervals of geohazards are still poorly understood. Examples include, but are not limited to, earthquakes and volcanic eruptions along the active tectonic margins of the Mediterranean and Sea of Marmara, landslides on both active and passive margins, and tsunamites and seismites in the sedimentary record that suggest a long history of similar events. The development of geophysical networks, drilling, sampling and long-term monitoring are crucial to the understanding of earthquake, landslide, and tsunami processes, and to mitigate the associated risks in densely populated and industrialized regions such as Europe. Scientific drilling, particularly in the submarine setting, offers a unique tool to obtain drill core samples, borehole measurements and long-term observations. Hence, it is a critical technology to investigate past, present, and possible future influences of hazardous processes in this area. The

  15. Modeling malware propagation using a carrier compartment (United States)

    Hernández Guillén, J. D.; Martín del Rey, A.


    The great majority of mathematical models proposed to simulate malware spreading are based on systems of ordinary differential equations. These are compartmental models where the devices are classified according to some types: susceptible, exposed, infectious, recovered, etc. As far as we know, there is not any model considering the special class of carrier devices. This type is constituted by the devices whose operative systems is not targeted by the malware (for example, iOS devices for Android malware). In this work a novel mathematical model considering this new compartment is considered. Its qualitative study is presented and a detailed analysis of the efficient control measures is shown by studying the basic reproductive number.

  16. The upper hand on compartment syndrome.

    LENUS (Irish Health Repository)

    Dolan, Roisin T


    Metacarpal fractures are common injuries, accounting for approximately 30% to 40% of all hand fractures and with a lifetime incidence of 2.5%. Traditionally regarded as an innocuous injury, metacarpal fractures tend to be associated with successful outcomes after closed reduction and immobilization. Hand compartment syndrome (HCS) is a rare clinical entity with potential devastating consequences in terms of loss of function and quality-of-life outcomes. We discuss the case of a 44-year-old woman presenting with multiple closed metacarpal fractures as a result of low-energy trauma, complicated by acute HCS. We review the presentation, clinical assessment, and optimal surgical management of acute HCS with reference to international literature.

  17. Compartment syndrome can also be seen in the forearm

    DEFF Research Database (Denmark)

    Asmar, Ali; Broholm, Rikke; Bülow, Jens


    Chronic compartment syndrome is a challenge for the clinician and symptomatic similar to neuropathies, tenosynovitis, stress fractures and referred pain from lumbar cervicalis. Thus, chronic compartment syndrome of the upper extremities is probably an underdiagnosed condition. In patients...... with stress-induced pain in the upper limbs, chronic compartment syndrome should be considered - particularly in young patients with high physical activity. Despite limited literature, the effect of surgical treatment is promising....

  18. Dynamic Compartments in the Imperative π-Calculus (United States)

    John, Mathias; Lhoussaine, Cédric; Niehren, Joachim

    Dynamic compartments with mutable configurations and variable volumes are of basic interest for the stochastic modeling of biochemistry in cells. We propose a new language to express dynamic compartments that we call the imperative π -calculus. It is obtained from the attributed π -calculus by adding imperative assignment operations to a global store. Previous approaches to dynamic compartments are improved in flexibility or efficiency. This is illustrated by an appropriate model of osmosis and a correct encoding of bioambBioAmbients.

  19. Tsunami Generated by a Two-Phase Submarine Debris Flow (United States)

    Pudasaini, S. P.


    The general two-phase debris flow model proposed by Pudasaini (2011) is employed to study subaerial and submarine debris flows, and the tsunami generated by the debris impact at lakes and oceans. The model includes several essential physical aspects, including Mohr-Coulomb plasticity for the solid stress, while the fluid stress is modelled as a solid volume fraction gradient enhanced non-Newtonian viscous stress. The generalized interfacial momentum transfer includes the viscous drag, buoyancy, and the virtual mass. The generalized drag covers both the solid-like and fluid-like contributions, and can be applied to linear to quadratic drags. Strong couplings exist between the solid and the fluid momentum transfer. The advantage of the real two-phase debris flow model over classical single-phase or quasi-two-phase models is that by considering the solid (and/or the fluid) volume fraction appropriately, the initial mass can be divided into several (even mutually disjoint) parts; a dry (landslide or rock slide), a fluid (water or muddy water; e.g., dams, rivers), and a general debris mixture material as needed in real flow simulations. This offers a unique and innovative opportunity within a single framework to simultaneously simulate (a) the sliding debris (or landslide), (b) the water lake or ocean, (c) the debris impact at the lake or ocean, (d) tsunami generation and propagation, (e) mixing and separation between the solid and the fluid phases, and (f) sediment transport and deposition process in the bathymetric surface. The new model is applied to two-phase subaerial and submarine debris flows. Benchmark numerical simulations reveal that the dynamics of the debris impact induced tsunamis are fundamentally different than the tsunami generated by pure rock avalanche and landslides. Special attention is paid to study the basic features of the debris impact to the mountain lakes or oceans. This includes the generation, amplification and propagation of the multiple

  20. Coping with the diagnostic complexities of the compartment syndrome (United States)

    Mubarak, S. J.; Hargens, A. R.; Karkal, S. S.


    This review recognizes that, given the various complexities associated with the condition, no pat answers can be given to fit every patient with the compartment syndrome. The authors first give a definition of the syndrome, together with a brief account of how this self-perpetuating pathologic cycle is triggered. Next, they delineate specific anatomical features of compartments that are likely to be involved, and follow this with an inventory of symptoms and signs to look for in suspected cases. After sorting out the entities that can mimic the compartment syndrome, the authors describe three essential techniques of measuring tissue pressure, which can prove invaluable in diagnosing the compartment syndrome.

  1. Lateral canthotomy and cantholysis: emergency management of orbital compartment syndrome. (United States)

    Rowh, Adam D; Ufberg, Jacob W; Chan, Theodore C; Vilke, Gary M; Harrigan, Richard A


    Orbital compartment syndrome is a sight-threatening emergency. Vision may be preserved when timely intervention is performed. To present a case of orbital compartment syndrome caused by traumatic retrobulbar hemorrhage and the procedure of lateral canthotomy and cantholysis, reviewed with photographic illustration. Lateral canthotomy and cantholysis are readily performed at the bedside with simple instruments. The procedure may prevent irreversible blindness in cases of acute orbital compartment syndrome. Emergency physicians should be familiar with lateral canthotomy and cantholysis in the management of orbital compartment syndrome to minimize the chance of irreversible visual loss. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Compartment Syndrome After Varicose Vein Surgery Evidenced by CT Images. (United States)

    Wang, Sheng-Min; Kim, Maru


    A 21-year-old man developed compartment syndrome after a varicose vein surgery. Because of a lack of appropriate diagnostic apparatus, it was not possible to measure calf pressure. The only diagnostic tool available was computed tomography (CT). With the aid of CT, faster diagnosis of the compartment syndrome was possible, leading to appropriate management. By providing unique CT images of a patient before and after having compartment syndrome and after a fasciotomy, this study could add valuable references for diagnosis of compartment syndrome using CT. © The Author(s) 2014.

  3. Acute compartment syndrome in lower extremity musculoskeletal trauma. (United States)

    Olson, Steven A; Glasgow, Robert R


    Acute compartment syndrome is a potentially devastating condition in which the pressure within an osseofascial compartment rises to a level that decreases the perfusion gradient across tissue capillary beds, leading to cellular anoxia, muscle ischemia, and death. A variety of injuries and medical conditions may initiate acute compartment syndrome, including fractures, contusions, bleeding disorders, burns, trauma, postischemic swelling, and gunshot wounds. Diagnosis is primarily clinical, supplemented by compartment pressure measurements. Certain anesthetic techniques, such as nerve blocks and other forms of regional and epidural anesthesia, reportedly contribute to a delay in diagnosis. Basic science data suggest that the ischemic threshold of normal muscle is reached when pressure within the compartment is elevated to 20 mm Hg below the diastolic pressure or 30 mm Hg below the mean arterial blood pressure. On diagnosis of impending or true compartment syndrome, immediate measures must be taken. Complete fasciotomy of all compartments involved is required to reliably normalize compartment pressures and restore perfusion to the affected tissues. Recognizing compartment syndromes requires having and maintaining a high index of suspicion, performing serial examinations in patients at risk, and carefully documenting changes over time.

  4. Hybrid plasmachemical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lelevkin, V. M., E-mail:; Smirnova, Yu. G.; Tokarev, A. V. [Kyrgyz-Russian Slavic University (Kyrgyzstan)


    A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

  5. Attrition reactor system (United States)

    Scott, Charles D.; Davison, Brian H.


    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur.

  6. Guidebook to nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Nero, A.V. Jr.


    A general introduction to reactor physics and theory is followed by descriptions of commercial nuclear reactor types. Future directions for nuclear power are also discussed. The technical level of the material is suitable for laymen.

  7. The Impact of the General Board of the Navy on Interwar Submarine Design (United States)


    Navy had developed the Gato class submarine, which was successful independently operating in the vast Pacific Ocean in support of War Plan Orange. The...development of the Gato class submarine, which was successful independently operating in the vast Pacific Ocean in support of War Plan Orange. The...

  8. Procurements by the Non-Acoustic Anti-Submarine Warfare Program Through the Environmental Technologies Laboratory (United States)


    General, DoD, on contract offloading, including Report No. 93-068, " Procurement of Services for the Non-Acoustic Anti-Submarine Warfare Program...contract administration in response to Audit Report No. 93-042. Report No. 93-068, " Procurement of Services for the Non-Acoustic Anti- Submarine Warfare

  9. Study on the locational criteria for submarine rock repositories of low and medium level radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, G. H.; Kang, W. J.; Kim, T. J. and others [Chungnam National Univ., Taejon (Korea, Republic of)


    Submarine repositories have significant advantages over their land counterparts locating close to the areas of daily human activities. Consequently, the construction of submarine repositories on the vast continental shelves around Korean seas is considered to be highly positive. In this context, the development of locational criteria primarily targeting the safety of submarine rock repositories is very important.The contents of the present study are: analyzing characteristics of marine environment: Search of potential hazards to, and environmental impact by, the submarine repositories; Investigation of the oceanographic, geochemical, ecological and sedimentological characteristics of estuaries and coastal seas. Locating potential hazards to submarine repositories by: Bibliographical search of accidents leading to the destruction of submarine structures by turbidity currents and other potentials; Review of turbidity currents. Consideration of environmental impact caused by submarine repositories: Logistics to minimize the environmental impacts in site selection; Removal and dispersion processes of radionuclides in sea water. Analyses of oceanographical characteristics of, and hazard potentials in, the Korean seas. Evaluation of the MOST 91-7 criteria for applicability to submarine repositories and the subsequent proposition of additional criteria.

  10. Submarine landslides on the north continental slope of the South China Sea (United States)

    Wang, Weiwei; Wang, Dawei; Wu, Shiguo; Völker, David; Zeng, Hongliu; Cai, Guanqiang; Li, Qingping


    Recent and paleo-submarine landslides are widely distributed within strata in deep-water areas along continental slopes, uplifts, and carbonate platforms on the north continental margin of the South China Sea (SCS). In this paper, high-resolution 3D seismic data and multibeam data based on seismic sedimentology and geomorphology are employed to assist in identifying submarine landslides. In addition, deposition models are proposed that are based on specific geological structures and features, and which illustrate the local stress field over entire submarine landslides in deep-water areas of the SCS. The SCS is one of the largest fluvial sediment sinks in enclosed or semi-enclosed marginal seas worldwide. It therefore provides a set of preconditions for the formation of submarine landslides, including rapid sediment accumulation, formation of gas hydrates, and fluid overpressure. A new concept involving temporal and spatial analyses is tested to construct a relationship between submarine landslides and different time scale trigger mechanisms, and three mechanisms are discussed in the context of spatial scale and temporal frequency: evolution of slope gradient and overpressure, global environmental changes, and tectonic events. Submarine landslides that are triggered by tectonic events are the largest but occur less frequently, while submarine landslides triggered by the combination of slope gradient and over-pressure evolution are the smallest but most frequently occurring events. In summary, analysis shows that the formation of submarine landslides is a complex process involving the operation of different factors on various time scales.

  11. The risk of hydrogen explosion in a submarine p.I Catalytic combustion of hydrogen

    Directory of Open Access Journals (Sweden)

    Kłos Ryszard


    Full Text Available The series of articles discuss issues related to conducting high risk projects on the example of modernisation of hydrogen incinerators on a submarine. The article depicts a technical problem situation connected with catalytic hydrogen combustion on a submarine.

  12. Evaluation of the radiologic potential due to the nuclear submarine visits to the Rio de Janeiro port; Avaliacao do impacto radiologico potencial relativo a visita de submarinos nucleares ao Porto do Rio de Janeiro

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Jose Francisco


    Brazil is signatory of international protocols related to the visit of nuclear-powered vessels, aircraft carriers and submarines to Brazilian ports. The submarines, during their stay in Brazilian ports, inform that there is no release of radioactive material to the environment. However, the possibility of occurrence of accidents with environmental releases from PWR reactors is real. Between 1993 and 2003, 13 nuclear submarines visited Brazilian ports. This work aimed to evaluate the potential impact due to the visits of nuclear-powered ships and submarines to the port of the city of Rio de Janeiro, in relation to releases of radioactive materials to the environment, considering both routine releases and accidental situations. The models selected to perform the assessments took into account the scenarios to be simulated. Simple, but conservative methodologies were used for the evaluation of routine releases. For accidental releases, the dynamics of the materials dispersion into the environment were considered. The present study was mainly focalized on the initial phase of an accident. The doses for the crew of the Brazilian navy ships, for IRD teams performing environmental monitoring, and for the population around the Guanabara Bay, close to the points of anchorage, were assessed. The results indicated that, in normal operational conditions, no significant radiological impact due to the visit of nuclear submarines to the port of the city of Rio de Janeiro is expected, even considering the occurrence of small routine radionuclide releases. The analysis of accidental releases, however, indicated that the submarines should be located at a minimum distance of 2,5 km from inhabited areas in the coast of the Guanabara Bay. The need for environmental control and training of the teams involved in the attendance of the submarines, during the period of their visit, was also considered. The need for revising the procedures for the preoperational surveys to be performed at the

  13. The compartmented alginate fibres optimisation for bitumen rejuvenator encapsulation

    NARCIS (Netherlands)

    Tabaković, Amir; Copuroglu, O.; Post, W.; Garcia Espallargas, Santiago J.; Schlangen, H.E.J.G.


    This article presents development of a novel self-healing technology for asphalt pavements, where asphalt binder rejuvenator is encapsulated within the compartmented alginate fibres. The key objective of the study was to optimise the compartmented alginate fibre design, i.e., maximising amount of

  14. Radiographic predictors of compartment syndrome in tibial plateau fractures. (United States)

    Ziran, Bruce H; Becher, Stephen John


    The purpose of this article was to evaluate the relationship of radiographic features of tibial plateau fractures to the development of compartment syndrome. We hypothesized that the direction and degree of initial displacement of the femur on the tibia, and the amount of tibial widening (TW), were correlated with the development of compartment syndrome. Retrospective case-control study. Single level 1 trauma center. Retrospective evaluation of 158 patients with 162 plateau fractures. Grouping with and without compartment syndrome. The following data were obtained: age, sex, Schatzker and OTA/AO classification, open/closed status, TW, and femoral displacement (FD). A univariate statistical and a logistical regression analysis were performed to determine significance. The overall rate of compartment syndrome was 11%. Univariate analysis found both the TW and FD to be significant with respect to development of compartment syndrome (P compartment syndrome. Logistic regression found FD and Schatzker grade to be significant. Our study is the first to identify easily obtained radiographic parameters that correlate to the occurrence compartment syndrome. There may also be a relationship between TW and FD, as noted by regression result. This study helps to assess which patients with a fracture are at higher risk for developing a compartment syndrome. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

  15. Chronic Exertional Compartment Syndrome in a Healthy Young Man. (United States)

    Joubert, Sonia V; Duarte, Manuel A


    The purpose of this case report is to describe a patient who presented with symptoms of exercise-induced compartment syndrome and was later referred for bilateral fasciotomy surgery. A 21-year-old patient presented for chiropractic care with the inability to run due to foot paresthesia and weakness. An exertion test and compartment pressure test diagnosed exercise-induced compartment syndrome. Exertion test and compartment pressure test were used to identify and diagnose exercise-induced compartment syndrome. The patient was diagnosed with exercise-induced compartment syndrome. He was treated conservatively and referred for additional testing. The orthopedic surgeon requested that 12 weeks of conservative care be provided prior to testing; treatment consisted of chiropractic care and rehabilitation exercises. Following the 12 weeks of treatment, the patient did not significantly respond to conservative care. A compartment pressure test confirmed the initial diagnosis of exercise-induced compartment syndrome. The patient underwent a unilateral fasciotomy surgery and recovered fully. Following the surgery, the patient returned to the chiropractic clinic with the same presentation in the contralateral leg. The same protocol of management resulted in the same outcome. Two years after surgical intervention, the patient continues to maintain an active lifestyle, able to run 2 to 3 miles per day without any exacerbations or symptomatology. Clinical awareness, a detailed history, and thorough examination with reproduction of symptomatology are necessary to form a proper diagnosis and treatment plan for these patients. Therefore, multidisciplinary medical communication would prove to be the most beneficial approach for the patient.

  16. Spontaneous Compartment Syndrome of the Hand in Systemic Sclerosis. (United States)

    Tanagho, Andy; Hatab, Sameh; Youssef, Sally; Ansara, Sameh


    Compartment syndrome refers to a condition of compromised circulation within a limited space due to increased pressure within that space. The reduced tissue perfusion results in reduced venous drainage, leading to increased interstitial tissue pressure and subsequent compromised arterial flow. Although not as common as compartment syndrome of the leg and forearm, compartment syndrome of the hand is not rare and can lead to devastating sequelae as a result of tissue necrosis. Compartment syndrome of the hand has several etiologies, including trauma, arterial injury, thermal injury, and constrictive bandaging. The cardinal clinical sign is pain that is aggravated by passive stretching of the muscles within the involved compartments. Extremity function is usually restored with expeditious fasciotomy of the involved myofascial compartments, and complications, such as intrinsic muscular dysfunction and Volkmann's ischemic contracture, can usually be prevented. There are no reported cases of compartment syndrome of the hand in patients with systemic sclerosis or Raynaud's phenomenon. Systemic sclerosis is a form of scleroderma that affects the skin and internal organs. The limited cutaneous subset affects the skin of the extremities but is associated with a set of characteristic features that includes calcinosis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia. This report describes an unusual case of a patient who had spontaneous compartment syndrome of the hand. The patient's concomitant limited cutaneous systemic sclerosis may have played a role in this unusual occurrence. The diagnosis was based on the clinical picture, and the symptoms resolved after surgical decompression. Copyright 2015, SLACK Incorporated.

  17. A case of delayed presentation of thigh compartment syndrome. (United States)

    Wardi, Gabriel; Görtz, Simon; Snyder, Brian


    Thigh compartment syndrome is a rare and devastating process. It generally occurs within hours to days of a traumatic event, although cases have been reported nearly 2 weeks after the initial event. To evaluate the literature describing the timing between inciting event and presentation of thigh compartment syndromes, with a focus on delayed presentations of this rare condition. To describe the unique properties of thigh compartments, and finally, to review the anatomy and techniques needed to measure the compartment pressures of the thigh. A case of a 54-year-old man is presented. He sustained trauma to his thigh 17 days prior to presenting to our ED with severe, sudden-onset pain in his right thigh. Compartment pressures were measured and confirmed the diagnosis of compartment syndrome caused by two large intramuscular hematomas. No other contributing events were identified. Compartment syndrome in the thigh should be considered in patients with a concerning examination and a history of recent trauma. This particular case represents the longest reported time between injury and development of a thigh compartment syndrome. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Mannitol extravasation during partial nephrectomy leading to forearm compartment syndrome

    Directory of Open Access Journals (Sweden)

    Bradley A. Erickson


    Full Text Available We present the first known complication of forearm compartment syndrome after mannitol infusion during partial nephrectomy. We stress the importance of excellent intravenous catheter access and constant visual monitoring of the intravenous catheter site during and after mannitol infusion as ways to prevent this complication. Prompt recognition of compartment syndrome with appropriate intervention can prevent long-term sequelae.


    Epler, E.P.; Hanauer, S.H.; Oakes, L.C.


    A control system is described for a nuclear reactor using enriched uranium fuel of the type of the swimming pool and other heterogeneous nuclear reactors. Circuits are included for automatically removing and inserting the control rods during the course of normal operation. Appropriate safety circuits close down the nuclear reactor in the event of emergency.

  20. Experimental and in-silico investigation of population heterogeneity in continuous Sachharomyces cerevisiae scale-down fermentation in a novel two-compartment setup

    DEFF Research Database (Denmark)

    Heins, Anna-Lena; Lencastre Fernandes, Rita; Gernaey, Krist


    BACKGROUND: In large-scale bioreactors, microbes often encounter fluctuating conditions of nutrient and oxygen supply, resulting in different microbial behavior at the different scales. The underlying reason is spatial heterogeneity, caused by limited mixing capabilities at production scale....... Consequently, scale-up of processes is challenging and there is a need for laboratory-scale reactor setups that can mimic large-scale conditions to enhance the understanding of how fluctuating environmental conditions affect microbial physiology. RESULTS: A two-compartment, scale-down setup, consisting of two...... interconnected stirred tank reactors was used in combination with mathematical modeling, to mimic large-scale continuous cultivations. One reactor represents the feeding zone with high glucose concentration and low oxygen, whereas the other one represents the remaining reactor volume. An earlier developed...

  1. Post-eruptive Submarine Terrace Development of Capelinhos, Azores (United States)

    Zhongwei Zhao, Will; Mitchell, Neil; Quartau, Rui; Tempera, Fernando; Bricheno, Lucy


    Erosion of the coasts of volcanic islands by waves creates shallow banks, but how erosion proceeds with time to create them and how it relates to wave climate is unclear. In this study, historical and recent marine geophysical data collected around the Capelinhos promontory (western Faial Island, Azores) offer an unusual opportunity to characterize how a submarine terrace developed after the eruption. The promontory was formed in 1957/58 during a Surtseyan eruption that terminated with extensive lava forming new rocky coastal cliffs. Historical measurements of coastline position are supplemented here with coastlines measured from 2004 and 2014 Google Earth images in order to characterize coastline retreat rate and distance for lava- and tephra-dominated cliffs. Swath mapping sonars were used to characterize the submarine geometry of the resulting terrace (terrace edge position, gradient and morphology). Limited photographs are available from a SCUBA dive and drop-down camera deployments to ground truth the submarine geomorphology. The results reveal that coastal retreat rates have decreased rapidly with the time after the eruption, possibly explained by the evolving resistance to erosion of cliff base materials. Surprisingly, coastline retreat rate decreases with terrace width in a simple inverse power law with terrace width. We suspect this is only a fortuitous result as wave attenuation over the terrace will not obviously produce the variation, but nevertheless it shows how rapidly the retreat rate declines. Understanding the relationship between terrace widening shelf and coastal cliff retreat rate may be more widely interesting if they can be used to understand how islands evolve over time into abrasional banks and guyots.

  2. Maximizing the probability an aerial anti-submarine torpedo detects its target (United States)

    Wang, Zhi-Jie


    As a result of the high speed of anti-submarine patrol aircraft as well as their wide range, high efficiency and other characteristics, aerial torpedoes released by anti-submarine patrol aircraft have become the key anti submarine tool. In order to improve operational efficiency, a deep study was made of the target detection probabilities for aerial torpedoes released by anti-submarine patrol aircraft. The operational modes of aerial torpedoes were analyzed and mathematical-simulation models were then established. The detection probabilities of three attacking modes were then calculated. Measures were developed for improving low probabilities of detection when attacking a probable target position. This study provides an important frame of reference for the operation of aerial torpedo released by anti-submarine patrol aircraft.

  3. Main devices design of submarine oil-water separation system (United States)

    Cai, Wen-Bin; Liu, Bo-Hong


    In the process of offshore oil production, in order to thoroughly separate oil from produced fluid, solve the environment problem caused by oily sewage, and improve the economic benefit of offshore drilling, from the perspective of new oil-water separation, a set of submarine oil-water separation devices were designed through adsorption and desorption mechanism of the polymer materials for crude oil in this paper. The paper introduces the basic structure of gas-solid separation device, periodic separation device and adsorption device, and proves the rationality and feasibility of this device.

  4. Submarine glaciated landscapes of central and northern British Columbia, Canada (United States)

    Shaw, John; Lintern, Gwyn


    Recent systematic multibeam sonar mapping and ground-truthing surveys in the fjords and coastal waters of central and northern British Columbia, Canada, provide information on glacial processes associated with the Cordilleran Ice Sheet, and also on postglacial processes that have strongly modified the glacial terrain. During the last glacial maximum, ice covered the Coast Range, except for nunataks. Convergent streamlined glacial landforms in the Strait of Georgia testify to a strong flow of ice towards the southeast, between Vancouver Island and the mainland. During ice retreat, thick deposits of acoustically stratified glaciomarine mud were deposited in glacially over deepened basins. Retreat through the Douglas Channel fjord system was punctuated by still stands, resulting in a series of submarine moraines. Postglacial processes have created a suite of landforms that mask the primary glacial terrain: 1) Fjord floors host thick deposits of acoustically transparent postglacial mud with highly variable distribution: banks up to 80-m thick are commonly adjacent to erosional zones with glaciomarine mud exposed at the seafloor; 2) In this region of high precipitation and snowpack melt, numerous cone-shaped Holocene fan deltas developed on the fjord sidewalls transport coarse sediment to the fjord floors. Larger deltas are developed at fjord heads, notably at Kitimat and Kildala; 3) Submarine slope failures in this tectonically active area have resulted in a suite of mass transport deposits on sidewalls and fjord floors. The very large submarine slope failures at Camano Sound and KitKat Inlet occurred on the steep, rear facets of large transverse moraines, and involved the failure of glaciomarine sediment that moved into deeper basins, perhaps as a retrogressive failure. The ages of these events are unknown, although the presence of postglacial mud in the slide scar at Caamano suggests that the event at that location occurred in the late glacial or early Holocene. Also

  5. Micro-tunneling as an alternative to submarine cable

    Energy Technology Data Exchange (ETDEWEB)

    Russo, D.A. [Seattle City Light, WA (United States); Hansen, D. [CH2M Hill, Bellevue, WA (United States)


    The geography that gives Seattle its beauty can pose unique challenges for the engineers attempting to provide service to the customers who live near or upon these features. Steep, wooded hills and greenbelts create familiar problems of construction and right-of-way maintenance. The waterways and adjoining shoreline zones present a more difficult set of requirements. When Seattle City Light determined it was necessary to install 2-26 KV feeders across the Salmon Bay waterway, they discovered that submarine cables could not be used. Shallow angle directional drilling and micro-tunneling were examined and it was fond that a microtunneled duct bank was the best method to use.

  6. Abdominal Compartment Syndrome Secondary to Chronic Constipation

    Directory of Open Access Journals (Sweden)

    Helene Flageole


    Full Text Available Abdominal compartment syndrome (ACS is defined as an elevated intraabdominal pressure with evidence of organ dysfunction. The majority of published reports of ACS are in neonates with abdominal wall defects and in adults following trauma or burns, but it is poorly described in children. We describe the unusual presentation of an 11-year-old boy with a long history of chronic constipation who developed acute ACS requiring resuscitative measures and emergent disimpaction. He presented with a 2-week history of increasing abdominal pain, nausea, diminished appetite and longstanding encopresis. On exam, he was emaciated with a massively distended abdomen with a palpable fecaloma. Abdominal XR confirmed these findings. Within 24 hours of presentation, he became tachycardic and oliguric with orthostatic hypotension. Following two enemas, he acutely deteriorated with severe hypotension, marked tachycardia, acute respiratory distress, and a declining mental status. Endotracheal intubation, fluid boluses, and vasopressors were commenced, followed by emergent surgical fecal disimpaction. This resulted in rapid improvement in vital signs. He has been thoroughly investigated and no other condition apart from functional constipation has been identified. Although ACS secondary to constipation is extremely unusual, this case illustrates the need to actively treat constipation and what can happen if it is not.

  7. The Plasma Electrolysis Phenomenon in a Two-Compartment Reactor for Chlor-Alkali Production

    Directory of Open Access Journals (Sweden)

    Nelson Saksono


    Full Text Available Chlor-alkali is one of the most important processes in the chemical industry. It produces chlorine and caustic soda, which become the main feedstock of daily products. The aim of this study is to report the phenomenon of plasma electrolysis and how it can be used in chlor-alkali production for more efficient energy consumption. When the plasma is formed, the current fluctuates and gradually declines. Plasma electrolysis begins with the process of electrolysis itself. Due to Joule heating, gas bubbles are formed and a sheath is made on both electrodes, resulting in the plasma field. Plasma electrolysis can be identified by its radical production. The higher the voltage and concentration, the greater the production of radicals. In 10 minutes or less, the number of OH radicals produced can reach 4 ppm at 400 V and 0.1 M. This amount is relatively small and is caused by other reactions consuming OH radicals to form other radicals such as chlorine. The energy consumption of plasma electrolysis in this study can reach 16 kJ/mmol Cl2 at 0.5 M NaCl solution.

  8. Nuclear reactor overflow line (United States)

    Severson, Wayne J.


    The overflow line for the reactor vessel of a liquid-metal-cooled nuclear reactor includes means for establishing and maintaining a continuous bleed flow of coolant amounting to 5 to 10% of the total coolant flow through the overflow line to prevent thermal shock to the overflow line when the reactor is restarted following a trip. Preferably a tube is disposed concentrically just inside the overflow line extending from a point just inside the reactor vessel to an overflow tank and a suction line is provided opening into the body of liquid metal in the reactor vessel and into the annulus between the overflow line and the inner tube.

  9. Light water reactor safety

    CERN Document Server

    Pershagen, B


    This book describes the principles and practices of reactor safety as applied to the design, regulation and operation of light water reactors, combining a historical approach with an up-to-date account of the safety, technology and operating experience of both pressurized water reactors and boiling water reactors. The introductory chapters set out the basic facts upon which the safety of light water reactors depend. The central section is devoted to the methods and results of safety analysis. The accidents at Three Mile Island and Chernobyl are reviewed and their implications for light wate

  10. Nuclear reactor physics

    CERN Document Server

    Stacey, Weston M


    Nuclear reactor physics is the core discipline of nuclear engineering. Nuclear reactors now account for a significant portion of the electrical power generated worldwide, and new power reactors with improved fuel cycles are being developed. At the same time, the past few decades have seen an ever-increasing number of industrial, medical, military, and research applications for nuclear reactors. The second edition of this successful comprehensive textbook and reference on basic and advanced nuclear reactor physics has been completely updated, revised and enlarged to include the latest developme

  11. Spinning fluids reactor (United States)

    Miller, Jan D; Hupka, Jan; Aranowski, Robert


    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  12. Anaerobic digestion model no. 1-based distributed parameter model of an anaerobic reactor: I. Model development. (United States)

    Mu, S J; Zeng, Y; Wu, P; Lou, S J; Tartakovsky, B


    This work presents a distributed parameter model of the anaerobic digestion process. The model is based on the Anaerobic digestion model no. 1 (ADM1) and was developed to simulate anaerobic digestion process in high-rate reactors with significant axial dispersion, such as in upflow anaerobic sludge bed (UASB) reactors. The model, which was named ADM1d, combines ADM1's kinetics of biomass growth and substrate transformation with axial dispersion material balances. ADM1d uses a hyperbolic tangent function to describe biomass distribution within a one compartment model. A comparison of this approach with a two-compartment, sludge bed - liquid above the bed, model showed similar simulation results while the one-compartment model had less equations. A comparison of orthogonal collocation and finite difference algorithms for numerical solution of ADM1d showed better stability of the finite difference algorithm.

  13. Functional outcome of tibial fracture with acute compartment syndrome and correlation to deep posterior compartment pressure (United States)

    Goyal, Saumitra; Naik, Monappa A; Tripathy, Sujit Kumar; Rao, Sharath K


    AIM To measure single baseline deep posterior compartment pressure in tibial fracture complicated by acute compartment syndrome (ACS) and to correlate it with functional outcome. METHODS Thirty-two tibial fractures with ACS were evaluated clinically and the deep posterior compartment pressure was measured. Urgent fasciotomy was needed in 30 patients. Definite surgical fixation was performed either primarily or once fasciotomy wound was healthy. The patients were followed up at 3 mo, 6 mo and one year. At one year, the functional outcome [lower extremity functional scale (LEFS)] and complications were assessed. RESULTS Three limbs were amputated. In remaining 29 patients, the average times for clinical and radiological union were 25.2 ± 10.9 wk (10 to 54 wk) and 23.8 ± 9.2 wk (12 to 52 wk) respectively. Nine patients had delayed union and 2 had nonunion who needed bone grafting to augment healing. Most common complaint at follow up was ankle stiffness (76%) that caused difficulty in walking, running and squatting. Of 21 patients who had paralysis at diagnosis, 13 (62%) did not recover and additional five patients developed paralysis at follow-up. On LEFS evaluation, there were 14 patients (48.3%) with severe disability, 10 patients (34.5%) with moderate disability and 5 patients (17.2%) with minimal disability. The mean pressures in patients with minimal disability, moderate disability and severe disability were 37.8, 48.4 and 58.79 mmHg respectively (P < 0.001). CONCLUSION ACS in tibial fractures causes severe functional disability in majority of patients. These patients are prone for delayed union and nonunion; however, long term disability is mainly because of severe soft tissue contracture. Intra-compartmental pressure (ICP) correlates with functional disability; patients with relatively high ICP are prone for poor functional outcome. PMID:28567342

  14. Seismicity and sedimentation rate effects on submarine slope stability (United States)

    Ten Brink, U. S.; Andrews, B. D.; Miller, N. C.


    Large submarine mass-transport scars are commonly observed on continental margins, but are noticeably less abundant on margins that experience frequent earthquakes than on those that seldom experience them. This is a surprising observation, given that horizontal acceleration from earthquakes and associated strength loss from cyclic loading and liquefaction are commonly thought to provide the primary triggers for inducing failures and subsequent mass movements. Mapping submarine failure scars in ten margins worldwide, we find decreasing scar abundance with both increasing frequency of earthquakes and decreasing sedimentation rate. The decrease in scar abundance is interpreted to represent increasing slope stability. The increase in stability is non linear (power law with btectonic activity (salt diapirs, seamount subduction, etc.) leads to relatively rapid oversteepening of the slope, implying that the morphology of most margins is in fact, stable over many earthquake cycles. Note that the above correlation averages scar area and sedimentation rate over entire margin areas. Variations in sedimentation rate with time, such as over glacial-interglacial cycles, and intra-margin variations in seismic attenuation, sedimentation rate, composition, and pore pressure, have likely affected the abundance of slope failures in time and space.

  15. An Automatic Procedure for the Quantitative Characterization of Submarine Bedforms

    Directory of Open Access Journals (Sweden)

    Massimo Di Stefano


    Full Text Available A model for the extraction and quantitative characterization of submarine landforms from high-resolution digital bathymetry is presented. The procedure is fully automated and comprises two parts. The first part consists of an analytical model which extracts quantitative information from a Digital Elevation Model in the form of objects with similar parametric characteristics (terrain objects. The second part is a rule-based model where the terrain objects are reclassified into distinct landforms with well-defined three dimensional characteristics. For the focus of this work, the quantitative characterization of isolated dunes (height greater than 2 m is used to exemplify the process. The primary metrics used to extract terrain objects are the flatness threshold and the search radius, which are then used by the analytical model to identify the feature type. Once identified as dunes, a sequence of spatial analysis routines is applied to identify and compute metrics for each dune including length, height, width, ray of curvature, slope analysis for each stoss and lee side, and dune symmetry. Dividing the model into two parts, one scale-dependent and another centered around the shape of the landform, makes the model applicable to other submarine landforms like ripples, mega-ripples, and coral reefs, which also have well-defined three-dimensional characteristics.

  16. Fin propulsion on a human-powered submarine (United States)

    Anderson, Iain A.; Pocock, Benjamin; Harbuz, Antoni; Algie, Cam; Vochezer, Daniel; Chao, Ryan; Lu, Benjamin


    Nearly all surface and underwater vessels are driven by screw propulsion; ideal for coupling to rotary engines and well understood after over a century of development. But most aquatic creatures use fins for swimming. Although there are sound evolutionary reasons why fish have fins and not propellers, they are nevertheless agile, fast and efficient. Although fish-like robots such as the MIT Robotuna are providing good insight into fin-based swimming there are advantages for using humans in the experimental device. Like an airplane test pilot they can write crash reports. We present preliminary observations for the human powered finned submarine: Taniwha. The sub participated in the 2nd European International Submarine races in Gosport UK where it received a trophy for "Best Non-Propeller Performance". Two sets of Hobie Mirage fin drives fixed to the upper and lower rear surfaces of the sub are pedaled by the pilot. The pilot also has two levers at the front, one to pitch a pair of dive planes and one for yawing a large rudder. Good speed, we estimate to be greater than 6 m/s is possible with these fins although we haven't explored their full potential. Straying too near the surface or bottom can lead to an instability, synonymous to a stall, such that control is lost. The mechanism for this will be discussed and solutions offered. Fish are 400 million years in front of us but one day we'll catch them.

  17. Are tilt measurements useful in detecting tsunamigenic submarine landslides? (United States)

    Brune, Sascha; Babeyko, Andrey Y.; Sobolev, Stephan V.


    Large submarine landslides can generate dangerous tsunamis. Because of their long-period signal, detection of landslides by common seismological methods is difficult. Here we suggest a method of detecting submarine landslides by using an array of land-based tiltmeters. The displacement of a large volume of sediments during landsliding produces a detectable elastic response of the lithosphere. We propose a technique to calculate this response and to invert for tsunami relevant parameters like slide location, volume, and velocity. We exemplify our method by applying it to the Storegga slide west of Norway and other tsunamigenic landslide events. The parameter which can be most robustly estimated from tiltmeter array measurements is the product of slide volume and its velocity (slide tsunamigenic potential). This parameter also controls the amplitude of the generated tsunami wave. The inversion accuracy of this parameter and the estimated tsunami height near the coast depends on the noise level of tiltmeter measurements, distance of the tiltmeters from the slide, and slide tsunamigenic potential itself. The tsunamigenic potential of the most dangerous slides like Storegga can be estimated well by tiltmeters at the coast if the effective noise level does not exceed 50 nrad.

  18. A submarine fan in the Mesa Central, Mexico (United States)

    Silva-Romo, G.; Arellano-Gil, J.; Mendoza-Rosales, C.; Nieto-Obregón, J.


    The contact between the Guerrero and Sierra Madre tectonostratigraphic terranes has been proposed to lie in the Mesa Central, east of the city of Zacatecas. Marine Triassic units have been assigned to the Guerrero Terrane. It is here proposed that this contact occurs to the west of the city of Zacatecas and the Triassic marine sequence assigned to the Sierra Madre Terrane. We analyzed the stratigraphic record and structural features of pre-Late Jurassic sequences at four localities in the Mesa Central. They contain a marine turbiditic Triassic unit, which includes La Bellena, Taray, and Zacatecas Formations, and a continental unit of probable Middle Jurassic age. Triassic sandstones were derived from a cratonic area, without the influence of arc volcanism. The sequences were affected by two phases of deformation. The Triassic formations are unconformably overlain by a continental volcano-sedimentary sequence that contains fragments of sandstones derived from the underlying unit. Sedimentologic characteristics of the Triassic unit fit a submarine fan model. The submarine fan developed at the continental margin of Pangaea during Triassic times. Turbidite associations in the San Rafael Area indicate a middle fan depositional environment, while in the Real de Catorce Area, they correspond to the distal part (basin plain facies). At La Ballena and Zacatecas the turbidite associations occur in the middle part and perhaps the external part of the fan.

  19. Feasibility study of submarine diesel exhaust valve interspace coating application

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, W.; Zhou, M.; Bibby, D.; Huang, J.


    This document described a feasibility study conducted to evaluate surface coating systems applied to the surface of a diesel exhaust valve interspace on a VICTORIA Class submarine. A series of laboratory studies were conducted to determine the physical characteristics of the coatings, which will be subjected to high service temperatures, diesel exhaust gas, and seawater. The valves were made of Q1N steel castings. The surface coatings were designed to provide corrosion resistance and thermal protection to the valves. As part of the study, a survey was conducted on various state-of-the-art surface coating systems. Coatings were rated on their ability to protect the Q10 steel surface from corrosion, high temperatures and seawater. An additional requirement was that the coatings should not produce high amounts of hydrogen. Plating trials were conducted with a nickel-based alloy (Ni-Cu-P) placed on Q1N steel substrates with a hypophosphite reducing agent. The results of X-ray diffraction (XRD) analyses suggested that the coatings can also be used to protect the external surfaces of various submarine components. 54 refs., 4 tabs., 10 figs.

  20. Trace elements distribution in environmental compartments

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Juliana C. de; Peres, Sueli da Silva; Godoy, Maria Luiza D.P., E-mail: [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)


    Trace elements term defines the presence of low concentrations metals at environment. Some of them are considered biologically essential, as Co, Cu and Mn. Others can cause detriment to environment and human health, as Pb, Cd, Hg, As, Ti and U. A large number of them have radioactive isotopes, implying the evaluation of risks for human health should be done considering the precepts of environmental radiological protection. The ecosystem pollution with trace elements generates changes at the geochemistry cycle of these elements and in environmental quality. Soils have single characteristics when compared with another components of biosphere (air, water and biota), cause they introduce themselves not only as a drain towards contaminants, but also as natural buffer that control the transport of chemical elements and other substances for atmosphere, hydrosphere and biota. The main purpose of environmental monitoring program is to evaluate the levels of contaminants in the various compartments of the environment: natural or anthropogenic, and to assess the contribution of a potential contaminant source on the environment. Elemental Composition for the collected samples was determined by inductively coupled plasma mass spectroscopy. The main objective of this work was to evaluate the map baseline of concentration of interest trace elements in environmental samples of water, sediment and soil from Environmental Monitoring Program of Instituto de Radioprotecao e Dosimetria (IRD). The samples were analyzed using an inductively coupled plasma mass spectrometer (ICP-MS) at IRD. >From the knowledge of trace elements concentrations, could be evaluated the environmental quality parameters at the studied ecosystems. The data allowed evaluating some relevant aspects of the study of trace elements in soil and aquatic systems, with emphasis at the distribution, concentration and identification of main anthropic sources of contamination at environment. (author)

  1. Compartment syndrome causes systemic inflammation in a rat. (United States)

    Lawendy, A-R; Bihari, A; Sanders, D W; Badhwar, A; Cepinskas, G


    Compartment syndrome results from increased intra-compartmental pressure (ICP) causing local tissue ischaemia and cell death, but the systemic effects are not well described. We hypothesised that compartment syndrome would have a profound effect not only on the affected limb, but also on remote organs. Using a rat model of compartment syndrome, its systemic effects on the viability of hepatocytes and on inflammation and circulation were directly visualised using intravital video microscopy. We found that hepatocellular injury was significantly higher in the compartment syndrome group (192 PI-labelled cells/10(-1) mm(3), standard error of the mean (sem) 51) compared with controls (30 PI-labelled cells/10(-1) mm(3), sem 12, p compartment syndrome group (5 leukocytes/30s/10 000 μm(2), sem 1) than controls (0.2 leukocytes/30 s/10 000 μm(2), sem 0.2, p Compartment syndrome can be accompanied by severe systemic inflammation and end organ damage. This study provides evidence of the relationship between compartment syndrome in a limb and systemic inflammation and dysfunction in a remote organ. Cite this article: Bone Joint J 2016; 98-B:1132-7. ©2016 The British Editorial Society of Bone & Joint Surgery.

  2. Hydrogen peroxide probes directed to different cellular compartments.

    Directory of Open Access Journals (Sweden)

    Mikalai Malinouski


    Full Text Available Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells.Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events.We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells.

  3. Stochastic Turing Patterns: Analysis of Compartment-Based Approaches

    KAUST Repository

    Cao, Yang


    © 2014, Society for Mathematical Biology. Turing patterns can be observed in reaction-diffusion systems where chemical species have different diffusion constants. In recent years, several studies investigated the effects of noise on Turing patterns and showed that the parameter regimes, for which stochastic Turing patterns are observed, can be larger than the parameter regimes predicted by deterministic models, which are written in terms of partial differential equations (PDEs) for species concentrations. A common stochastic reaction-diffusion approach is written in terms of compartment-based (lattice-based) models, where the domain of interest is divided into artificial compartments and the number of molecules in each compartment is simulated. In this paper, the dependence of stochastic Turing patterns on the compartment size is investigated. It has previously been shown (for relatively simpler systems) that a modeler should not choose compartment sizes which are too small or too large, and that the optimal compartment size depends on the diffusion constant. Taking these results into account, we propose and study a compartment-based model of Turing patterns where each chemical species is described using a different set of compartments. It is shown that the parameter regions where spatial patterns form are different from the regions obtained by classical deterministic PDE-based models, but they are also different from the results obtained for the stochastic reaction-diffusion models which use a single set of compartments for all chemical species. In particular, it is argued that some previously reported results on the effect of noise on Turing patterns in biological systems need to be reinterpreted.

  4. Treatment of Atypical Compartment Syndrome Due to Proteus Infection. (United States)

    Stull, Justin; Bhat, Suneel; Miller, Andrew J; Hoffman, Ryan; Wang, Mark L


    Compartment syndrome is an orthopedic emergency with a multitude of etiologies. Although it is most commonly associated with trauma to the extremity, hematoma and infection are 2 rare etiologies of insidious compartment syndrome. Proteus mirabilis is an opportunistic gram-negative species that can infect the respiratory tract, urinary tract, and open wounds. The authors present the case of a 69-year-old woman who developed tissue necrosis and compartment syndrome secondary to an untreated hematoma infected by P mirabilis. This case involves an atypical presentation caused by an untreated infected hematoma, emphasizing the need for a high index of suspicion. Current literature supports immediate surgical intervention in the clinical scenario of fulminant compartment syndrome, regardless of compartment pressure findings. The probability of compartment syndrome in the patient presenting with pain, paresthesias, paresis, and pain with passive stretch, all of which were positive findings in this patient, has been reported to be 98%. Thus, Doppler evaluation and intercompartmental pressures were considered but forgone to expedite operative treatment. Emergent 4-compartment fasciotomies, with excision and debridement of nonviable tissue, are potentially limb-saving procedures, intended to limit loss of function and obviate the need for lower extremity amputation. The decision was made to perform a dual-incision fasciotomy to avoid contamination of the uninvolved compartments with a standard single-incision approach. To date, this represents the first report in the English literature of the insidious onset of tissue necrosis secondary to a Proteus-infected hematoma, highlighting a unique etiology of atypical compartment syndrome. [Orthopedics. 2017; 40(1):e176-e178.]. Copyright 2016, SLACK Incorporated.

  5. Silent compartment syndrome in children: a report of five cases. (United States)

    Lee, Christopher; Lightdale-Miric, Nina; Chang, Emory; Kay, Robert


    Compartment syndrome does not always present classically in the pediatric population, making clinical diagnosis uniquely challenging. The purpose of this study was to identify signs and symptoms of compartment syndrome that may help risk-stratify pediatric patients upon presentation, as well as to report outcomes of 'silent' compartment syndrome in children. A retrospective review of cases of 'silent' compartment syndrome at a level I pediatric trauma center between 2000 and 2010 was conducted. Patient demographics and clinical data were reviewed, including complications and patient outcomes. Radiographs taken at presentation, on intraoperative fluoroscopy, and at postoperative follow-up were reviewed for fracture type, and severity and outcome analyses. Five patients were found to have compartment syndrome without the presence of significant pain at rest or on passive range of motion. The study included three male and two female patients with a median age of 7 years. Three upper-extremity and two lower-extremity fractures were involved. The mean time from presentation to surgery was 14 h. At presentation, three of five patients had muscle paralysis, whereas at diagnosis of compartment syndrome, four of five had paralysis. Of the classic five P's, a maximum of two were found at diagnosis. The mean clinical follow-up period was 11 months (2-26 months). Long-term complications from compartment syndrome were found in one of five patients, who at the most recent follow-up, continued to be debilitated. This study reviews a series of cases of 'silent' compartment syndrome and confirms its atypical presentation. It is recommended that caution be used when assessing fractures with high risk for compartment syndrome in children, especially those complicated by nerve injury, as they do not always present in the classic manner, with missed diagnosis leading to significant functional deficits. IV.

  6. Neutron fluxes in test reactors

    Energy Technology Data Exchange (ETDEWEB)

    Youinou, Gilles Jean-Michel [Idaho National Lab. (INL), Idaho Falls, ID (United States)


    Communicate the fact that high-power water-cooled test reactors such as the Advanced Test Reactor (ATR), the High Flux Isotope Reactor (HFIR) or the Jules Horowitz Reactor (JHR) cannot provide fast flux levels as high as sodium-cooled fast test reactors. The memo first presents some basics physics considerations about neutron fluxes in test reactors and then uses ATR, HFIR and JHR as an illustration of the performance of modern high-power water-cooled test reactors.

  7. Current thinking about acute compartment syndrome of the lower extremity (United States)

    Shadgan, Babak; Menon, Matthew; Sanders, David; Berry, Gregg; Martin, Claude; Duffy, Paul; Stephen, David; O’Brien, Peter J.


    Acute compartment syndrome of the lower extremity is a clinical condition that, although uncommon, is seen fairly regularly in modern orthopedic practice. The pathophysiology of the disorder has been extensively described and is well known to physicians who care for patients with musculoskeletal injuries. The diagnosis, however, is often difficult to make. In this article, we review the clinical risk factors of acute compartment syndrome of the lower extremity, identify the current concepts of diagnosis and discuss appropriate treatment plans. We also describe the Canadian medicolegal environment in regard to compartment syndrome of the lower extremity. PMID:20858378

  8. Acute Idiopathic Compartment Syndrome of the Forearm in an Adolescent

    Directory of Open Access Journals (Sweden)

    Smith, Kelley


    Full Text Available Acute compartment syndrome (ACS is a condition typically associated with long bone fractures or severe trauma; however, non-traumatic etiologies also occur. We describe a case of an otherwise healthy female pediatric patient presenting with unilateral forearm pain without an inciting injury. Intracompartmental pressures of the forearm were measured and she was diagnosed with idiopathic compartment syndrome. Our goal is to encourage clinicians to consider acute compartment syndrome even in the absence of trauma. [West J Emerg Med. 2015;16(1:158-160.

  9. Occupational stress in submariners: the impact of isolated and confined work on psychological well-being. (United States)

    Brasher, Kate S; Dew, Angela B C; Kilminster, Shaun G; Bridger, Robert S


    This study aimed to identify work-related and personal factors associated with occupational stress in submariners. Work and well-being questionnaires were distributed to 219 male submariners (mean age 34 years), as part of a larger cohort study involving a stratified sample of 4951 Royal Navy (RN) personnel. The stress rate in submariners was 40%; significantly higher than the stress rate in the general RN, although once demographic factors were controlled for in a matched control sample, this difference was no longer significant. A summary model accounted for 49% of the variance in submariner stress, with key differences emerging between the occupational factors associated with stress in submariners and in the general RN. The longitudinal nature of this study permits stress in submariners to be monitored over 5 years, which will provide valuable insights into the chronicity of stress in this specialised occupational group. STATEMENT OF RELEVANCE: This paper contributes to the current literature on the negative impact of working in isolated conditions. It is demonstrated that occupational stress in submarines can be partially explained using current theories of stress in the workplace. However, the constraints of a restricted environment introduce additional factors which can also be associated with occupational stress.

  10. Measuring currents in submarine canyons: technological and scientific progress in the past 30 years (United States)

    Xu, J. P.


    The development and application of acoustic and optical technologies and of accurate positioning systems in the past 30 years have opened new frontiers in the submarine canyon research communities. This paper reviews several key advancements in both technology and science in the field of currents in submarine canyons since the1979 publication of Currents in Submarine Canyons and Other Sea Valleys by Francis Shepard and colleagues. Precise placements of high-resolution, high-frequency instruments have not only allowed researchers to collect new data that are essential for advancing and generalizing theories governing the canyon currents, but have also revealed new natural phenomena that challenge the understandings of the theorists and experimenters in their predictions of submarine canyon flow fields. Baroclinic motions at tidal frequencies, found to be intensified both up canyon and toward the canyon floor, dominate the flow field and control the sediment transport processes in submarine canyons. Turbidity currents are found to frequently occur in active submarine canyons such as Monterey Canyon. These turbidity currents have maximum speeds of nearly 200 cm/s, much smaller than the speeds of turbidity currents in geological time, but still very destructive. In addition to traditional Eulerian measurements, Lagrangian flow data are essential in quantifying water and sediment transport in submarine canyons. A concerted experiment with multiple monitoring stations along the canyon axis and on nearby shelves is required to characterize the storm-trigger mechanism for turbidity currents.

  11. The impact of discrete compartments of a multi-compartment collagen-GAG scaffold on overall construct biophysical properties. (United States)

    Weisgerber, D W; Kelkhoff, D O; Caliari, S R; Harley, B A C


    Orthopedic interfaces such as the tendon-bone junction (TBJ) present unique challenges for biomaterials development. Here we describe a multi-compartment collagen-GAG scaffold fabricated via lyophilization that contains discrete mineralized (CGCaP) and non-mineralized (CG) regions joined by a continuous interface. Modifying CGCaP preparation approaches, we demonstrated scaffold variants of increasing mineral content (40 vs. 80wt% CaP). We report the impact of fabrication parameters on microstructure, composition, elastic modulus, and permeability of the entire multi-compartment scaffold as well as discrete mineralized and non-mineralized compartments. Notably, individual mineralized and non-mineralized compartments differentially impacted the global properties of the multi-compartment composite. Of particular interest for the development of mechanically-loaded multi-compartment composites, the elastic modulus and permeability of the entire construct were governed primarily by the non-mineralized and mineralized compartments, respectively. Based on these results we hypothesize spatial variations in scaffold structural, compositional, and mechanical properties may be an important design parameter in orthopedic interface repair. © 2013 Elsevier Ltd. All rights reserved.

  12. Prediction of nuclear submariner adaptability from autonomic indices and Rorschach Inkblot responses. Interim report

    Energy Technology Data Exchange (ETDEWEB)

    Weybrew, B.B.; Molish, H.B.


    To identify the most valid predictors of submariner adaptability, the authors derived 23 indices from the responses of 170 nuclear submariners to the Rorschach Inkblot Test, 11 measures of Autonomic Nervous System (ANS) reactivity to contrived stress, and five adjustment criteria. Factor analysis of this 39x39 correlation matrix yielded two Rorschach Factors, one of which correlated with three criterion dimensions. Two unique factors were also discovered, one, a structured ANS factor, and the other, a complex criterion scale. Selected Rorschach scores and, to a lesser extent, certain ANS indices emanating from this study, may be usefully-valid predictors of the adaptability of nuclear submariners during long patrols.

  13. Fast Spectrum Reactors

    CERN Document Server

    Todd, Donald; Tsvetkov, Pavel


    Fast Spectrum Reactors presents a detailed overview of world-wide technology contributing to the development of fast spectrum reactors. With a unique focus on the capabilities of fast spectrum reactors to address nuclear waste transmutation issues, in addition to the well-known capabilities of breeding new fuel, this volume describes how fast spectrum reactors contribute to the wide application of nuclear power systems to serve the global nuclear renaissance while minimizing nuclear proliferation concerns. Readers will find an introduction to the sustainable development of nuclear energy and the role of fast reactors, in addition to an economic analysis of nuclear reactors. A section devoted to neutronics offers the current trends in nuclear design, such as performance parameters and the optimization of advanced power systems. The latest findings on fuel management, partitioning and transmutation include the physics, efficiency and strategies of transmutation, homogeneous and heterogeneous recycling, in addit...

  14. Compartment Syndrome of the Gluteus Medius Occurred without Bleeding or Trauma: A Case Report


    Kong, Gyu-Min; Kwon, Yong-Uk; Park, Jun-Ho


    Compartment syndrome is an ischemic change resulting from an increase in compartment pressure. Initially, patients present with direct tenderness and swelling, and the weak circulation secondary to compartment syndrome can eventually lead to motor and sensory impairment. If the increase in pressure results in neurological impairment, emergency intervention is required to decompress the compartment. Typically, compartment syndrome develops on forearms or lower legs. The gluteal compartment is ...

  15. Elimination behavior of shelter dogs housed in double compartment kennels

    National Research Council Canada - National Science Library

    Wagner, Denae; Newbury, Sandra; Kass, Philip; Hurley, Kate


    ... being. Dogs in animal shelters are often housed in one of two types of confinement housing - single kennels and rooms or double compartment kennels and rooms most often separated by a guillotine door...

  16. The Pathophysiology, Diagnosis and Current Management of Acute Compartment Syndrome (United States)

    Donaldson, James; Haddad, Behrooz; Khan, Wasim S


    Acute compartment syndrome (ACS) is a surgical emergency warranting prompt evaluation and treatment. It can occur with any elevation in interstitial pressure in a closed osseo-fascial compartment. Resultant ischaemic damage may be irreversible within six hours and can result in long-term morbidity and even death. The diagnosis is largely clinical with the classical description of ‘pain out of proportion to the injury’. Compartment pressure monitors can be a helpful adjunct where the diagnosis is in doubt. Initial treatment is with the removal of any constricting dressings or casts, avoiding hypotension and optimizing tissue perfusion by keeping the limb at heart level. If symptoms persist, definitive treatment is necessary with timely surgical decompression of all the involved compartments. This article reviews the pathophysiology, diagnosis and current management of ACS. PMID:25067973

  17. Diagnosis of compartment syndrome using a microwave-based detector (United States)

    Ling, Geoffrey S. F.; Riechers, Ronald G., Sr.; Pasala, Krishna M.; Blanchard, Jeremy; Rosner, Michael; Jarell, Abel; Yun, Catherine; Garcia-Pinto, Patricia; Song, Ki-Il; Day, Keith; Riechers, Ronald G., Jr.; Zeidman, Seth M.; Rhee, Peter; Ecklund, James M.; Fitzpatrick, Thomas; Lockhart, Stephen


    A novel method for identifying compartment syndrome is presented. This method is based on a novel device that uses electromagnetic waves in the microwave radio frequency (RF) region and a modified algorithm previously used for the estimation of the angle of arrival of radar signals. In this study, we employ this radio frequency triage tool (RAFT) to the clinical condition of compartment syndrome, which is a clinical condition where blood or edema in the muscle compartment of the leg leads to critical sichemia of that exptremity. In anesthetized pigs, RAFT, can detect changes in the RF signature from a leg is due to 2cc or greater of either blood or slaine (a surrogate of edema). These results are compared to clinical examination. RAFT is superior to clinical examination in its ability to detect compartment syndrome in pgis.

  18. A Case of Acute Atraumatic Compartment Syndrome of the Thigh. (United States)

    Gutfraynd, Alexander; Philpott, Sheila


    In the absence of trauma, compartment syndrome of the thigh is rare. Several case reports have described compartment syndrome in the presence of trauma, comorbid medical conditions, and acute muscle overuse. Very few reports have demonstrated an acute onset of atraumatic thigh compartment syndrome. A 24-year-old man presented to the Emergency Department (ED) with a painful and swollen left thigh immediately after a night of dancing at a concert. He was found to have an elevated intracompartmental quadriceps pressure of 45 mm Hg in the ED, which led to his transfer to the operating room for an emergent fasciotomy. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although acute, atraumatic compartment syndrome of the thigh is a rare entity, failure to diagnose it promptly can lead to muscle necrosis, permanent neurologic deficits, and amputation. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Fulminant crural compartment syndrome preceded by psychogenic polydipsia

    DEFF Research Database (Denmark)

    Ulstrup, Anton; Ugleholdt, Randi; Rasmussen, Jeppe Vejlgaard


    We report a case of bilateral anterolateral crural compartment syndrome elicited by hyponatraemia and psychogenic polydipsia. The unusual constellation of clinical findings and diminished pain expression made initial diagnostic procedures challenging. The possible pathogenesis and treatment options...

  20. Canthal cutdown for emergent treatment of orbital compartment syndrome. (United States)

    Strand, Andrew T; Czyz, Craig N; Gibson, Amanda


    This article evaluates the use of a "canthal cutdown" technique in orbital compartment syndrome in a cadaveric model. Twelve cadaver orbits were used to simulate orbital compartment syndrome using a blood analog solution. Two pressure probes, in different orbital locations, were used to monitor orbital pressure. Pressure was monitored during successive procedures: canthotomy, cantholysis, and canthal cutdown. Orbits were then re-injected with solution, simulating an active orbital hemorrhage, and pressure measurements were recorded over a 10-minute duration. No statistically significant difference was found between the two orbital pressure monitoring devices at each measurement point (p = 0.99). Significant pressure reductions, for both probes, were observed after canthal cutdown compared to initial measurement after injection of 20 mL blood analog (p compartment syndrome and temporizing treatment of compartment syndrome from active orbital hemorrhages.

  1. Propofol extravasation: a rare cause of compartment syndrome (United States)

    Kalraiya, Ashish Jain; Madanipour, Suroosh; Colaco, Henry; Cobiella, Carlos


    We detail a rare cause of forearm compartment syndrome that occurred in an 18-year-old patient who presented with a Glasgow Coma Scale of 13/15 after a mixed drug overdose and subsequently required intubation. She suffered extravasation of her propofol infusion, which resulted in intrinsic compression within her forearm muscle compartments. Fortunately, the diagnosis of compartment syndrome was made swiftly and the patient was taken to theatre within 3 h where she underwent an emergency forearm fasciotomy. She made an uneventful recovery and at follow-up her wounds had healed well with no associated morbidity or loss of function. The learning points of this study highlight the importance of thoroughly understanding the signs and symptoms of compartment syndrome while maintaining a high index of suspicion. In addition to a thorough history and examination, consideration of the potential underlying causes allows for a swifter diagnosis and a quicker transition to theatre. PMID:25953583

  2. Fire safety arrangement of inhabited pressurized compartments of manned spacecraft (United States)

    Bolodian, Ivan; Melikhov, Anatoliy; Tanklevskiy, Leonid


    The article deals with innovative technical solutions that provide fire safety in inhabited pressurized compartments of manned spacecraft by means of a fireproof device of inhabited pressurized compartments via application of engineering means of fire prevention and fire spreading prevention by lowering fire load in an inhabited pressurized module up to the point when the maximum possible levels of fire factors in an inhabited pressurized compartment of a manned spacecraft are prevented. Represented technical solutions are used at the present time according to stated recommendations during provision of fire safety of equipment created by a number of Russian organizations for equipage of inhabited pressurized compartments of spacecraft of the Russian segment of International space station.

  3. Elimination behavior of shelter dogs housed in double compartment kennels

    National Research Council Canada - National Science Library

    Wagner, Denae; Newbury, Sandra; Kass, Philip; Hurley, Kate


    .... Dogs in animal shelters are often housed in one of two types of confinement housing - single kennels and rooms or double compartment kennels and rooms most often separated by a guillotine door...

  4. Turbofan Engine Core Compartment Vent Aerodynamic Configuration Development Methodology (United States)

    Hebert, Leonard J.


    This paper presents an overview of the design methodology used in the development of the aerodynamic configuration of the nacelle core compartment vent for a typical Boeing commercial airplane together with design challenges for future design efforts. Core compartment vents exhaust engine subsystem flows from the space contained between the engine case and the nacelle of an airplane propulsion system. These subsystem flows typically consist of precooler, oil cooler, turbine case cooling, compartment cooling and nacelle leakage air. The design of core compartment vents is challenging due to stringent design requirements, mass flow sensitivity of the system to small changes in vent exit pressure ratio, and the need to maximize overall exhaust system performance at cruise conditions.

  5. Marine litter in submarine canyons of the Bay of Biscay (United States)

    van den Beld, Inge M. J.; Guillaumont, Brigitte; Menot, Lénaïck; Bayle, Christophe; Arnaud-Haond, Sophie; Bourillet, Jean-François


    Marine litter is a matter of increasing concern worldwide, from shallow seas to the open ocean and from beaches to the deep-seafloor. Indeed, the deep sea may be the ultimate repository of a large proportion of litter in the ocean. We used footage acquired with a Remotely Operated Vehicle (ROV) and a towed camera to investigate the distribution and composition of litter in the submarine canyons of the Bay of Biscay. This bay contains many submarine canyons housing Vulnerable Marine Ecosystems (VMEs) such as scleractinian coral habitats. VMEs are considered to be important for fish and they increase the local biodiversity. The objectives of the study were to investigate and discuss: (i) litter density, (ii) the principal sources of litter, (iii) the influence of environmental factors on the distribution of litter, and (iv) the impact of litter on benthic communities. Litter was found in all 15 canyons and at three sites on the edge of the continental shelf/canyon, in 25 of 29 dives. The Belle-île and Arcachon Canyons contained the largest amounts of litter, up to 12.6 and 9.5 items per 100 images respectively. Plastic items were the most abundant (42%), followed by fishing-related items (16%). The litter had both a maritime and a terrestrial origin. The main sources could be linked to fishing activities, major shipping lanes and river discharges. Litter appeared to accumulate at water depths of 801-1100 m and 1401-1700 m. In the deeper of these two depth ranges, litter accumulated on a geologically structured area, accounting for its high frequency at this depth. A larger number of images taken in areas of coral in the shallower of these two depth ranges may account for the high frequency of litter detection at this depth. A larger number of litter items, including plastic objects in particular, were observed on geological structures and in coral areas than on areas of bare substratum. The distribution of fishing-related items was similar for the various types of

  6. Particle sedimentation and diffusive convection in submarine clouds (United States)

    Carazzo, G.; Jellinek, M.; Turchyn, A. V.


    The longevity of submarine plumes generated by the release of hydrothermal fluids during crustal rupturing or by the rapid cooling of an erupting lava flow constrains the input of crustal-derived elements into the deep-ocean. Decades of observations of episodic "event plumes" suggest that a key process governing the dynamics of a submarine cloud spreading out laterally from a buoyant rising plume is the production of internal layering. Here, we use geological data on submarine clouds and a new experimental apparatus producing at laboratory scale turbulent, hot particle-laden plumes and clouds to show that this layering occurs where particle diffusive convection driven by the differential diffusion of heat and small mineral precipitates gives rise to a large scale double diffusive instability. We show that this "particle diffusive convection" can extend the longevity of an event plume to two years after its emplacement, allowing iron-sulfide minerals to dissolve and deliver iron to the deep-ocean. The very long residence time imposed by diffusive convective effects does not allow iron-oxide minerals to dissolve but may lead to the formation of iron-rich sediments at large distances from the point of emission. We develop a new theoretical model that includes both sedimentation and dissolution processes to quantify the potential amount of iron produced by the dissolution of iron-sulfide minerals settling through the cloud by diffusive convection. A key prediction is that hydrothermal systems could provide 75% of the global budget of dissolved iron in the deep-ocean. The consideration of scale-basin variations suggests that the Southern Hemisphere is probably the most impacted by hydrothermal iron, consistent with observations and global ocean models. Photographs showing the typical evolution of a lab-scale turbulent, hot particle-laden plume. At stage 1, the buoyant plume reaches a level of neutral buoyancy and spreads out laterally forming a neutrally buoyant cloud

  7. Hawaiian submarine manganese-iron oxide crusts - A dating tool? (United States)

    Moore, J.G.; Clague, D.A.


    Black manganese-iron oxide crusts form on most exposed rock on the ocean floor. Such crusts are well developed on the steep lava slopes of the Hawaiian Ridge and have been sampled during dredging and submersible dives. The crusts also occur on fragments detached from bedrock by mass wasting, on submerged coral reefs, and on poorly lithified sedimentary rocks. The thickness of the crusts was measured on samples collected since 1965 on the Hawaiian Ridge from 140 dive or dredge localities. Fifty-nine (42%) of the sites were collected in 2001 by remotely operated vehicles (ROVs). The thinner crusts on many samples apparently result from post-depositional breakage, landsliding, and intermittent burial of outcrops by sediment. The maximum crust thickness was selected from each dredge or dive site to best represent crusts on the original rock surface at that site. The measurements show an irregular progressive thickening of the crusts toward the northwest-i.e., progressive thickening toward the older volcanic features with increasing distance from the Hawaiian hotspot. Comparison of the maximum crust thickness with radiometric ages of related subaerial features supports previous studies that indicate a crust-growth rate of about 2.5 mm/m.y. The thickness information not only allows a comparison of the relative exposure ages of two or more features offshore from different volcanoes, but also provides specific age estimates of volcanic and landslide deposits. The data indicate that some of the landslide blocks within the south Kona landslide are the oldest exposed rock on Mauna Loa, Kilauea, or Loihi volcanoes. Crusts on the floors of submarine canyons off Kohala and East Molokai volcanoes indicate that these canyons are no longer serving as channelways for downslope, sediment-laden currents. Mahukona volcano was approximately synchronous with Hilo Ridge, both being younger than Hana Ridge. The Nuuanu landslide is considerably older than the Wailau landslide. The Waianae

  8. Newly recognized submarine slide complexes in the southern California Bight (United States)

    Conrad, J. E.; Lee, H. J.; Edwards, B. D.; McGann, M.; Sliter, R. W.


    New high-resolution bathymetric and seismic-reflection surveys have imaged large (7) individual overlapping slides along the western margin of Santa Cruz Basin (SCB slide); 2) a series of slumps and slide scars on the slope south of San Pedro shelf (SPS slide); and 3) a slope failure along the shelf edge in northern San Diego County, termed the Del Mar slide. The SCB slide complex extends for 30 km along the western slope of Santa Cruz Basin, with debris lobes extending 5-8 km into the basin. Head scarps of some of these slides are 50-75 m high. The SPS slide complex also appears to consist of multiple slides, which roughly parallel the Palos Verdes Fault and the San Gabriel Canyon submarine channel on the shelf edge and slope south of San Pedro shelf. Slide deposits associated with this complex are only partially mapped due to limited high-resolution bathymetric coverage, but extend to the south in the area SW of Lasuen Knoll. Seismic-reflection profiles show that some of these deposits are up to 20 m thick. The Del Mar slide is located about 10 km north of La Jolla Canyon and extends about 6 km along the shelf edge. The head scarp lies along the trend of a branch of the Rose Canyon Fault Zone. Radiocarbon ages of sediment overlying this slide indicate the Del Mar slide is approximately 12-16 ka. These large slide complexes have several characteristics in common. Nearly all occur in areas of tectonic uplift. All of the complexes show evidence of recurrent slide activity, exhibiting multiple headwall scarps and debris lobes, and where available, high-resolution seismic-reflection profiles of these slide areas provide evidence of older, buried mass transport deposits. Assuming typical sedimentation rates, the recurrence interval of major slide events appears to be on the order of tens of thousands of years. Most of the slide complexes do not appear to be located in areas of high sediment input. The SCB and Del Mar slides are in areas receiving relatively small


    Spinrad, B.I.


    A novel thermal reactor was designed in which a first reflector formed from a high atomic weight, nonmoderating material is disposed immediately adjacent to the reactor core. A second reflector composed of a moderating material is disposed outwardly of the first reflector. The advantage of this novel reflector arrangement is that the first reflector provides a high slow neutron flux in the second reflector, where irradiation experiments may be conducted with a small effect on reactor reactivity.

  10. Acute pediatric leg compartment syndrome in chronic myeloid leukemia. (United States)

    Cohen, Eric; Truntzer, Jeremy; Trunzter, Jeremy; Klinge, Steve; Schwartz, Kevin; Schiller, Jonathan


    Acute compartment syndrome is an orthopedic surgical emergency and may result in devastating complications in the setting of delayed or missed diagnosis. Compartment syndrome has a variety of causes, including posttraumatic or postoperative swelling, external compression, burns, bleeding disorders, and ischemia-reperfusion injury. Rare cases of pediatric acute compartment syndrome in the setting of acute myeloid leukemia and, even less commonly, chronic myeloid leukemia have been reported. The authors report the first known case of pediatric acute compartment syndrome in a patient without a previously known diagnosis of chronic myeloid leukemia. On initial examination, an 11-year-old boy presented with a 2-week history of progressive left calf pain and swelling after playing soccer. Magnetic resonance imaging scan showed a hematoma in the left superficial posterior compartment. The patient had unrelenting pain, intermittent lateral foot parethesias, and inability to bear weight. Subsequently, he was diagnosed with acute compartment syndrome and underwent fasciotomy and evacuation of a hematoma. Laboratory results showed an abnormal white blood cell count of 440×10(9)/L (normal, 4.4-11×10(9)) and international normalized ratio of 1.3 (normal, 0.8-1.2). Further testing included the BCR-ABL1 fusion gene located on the Philadelphia chromosome, leading to a diagnosis of chronic myeloid leukemia. Monotherapy with imatinib mesylate (Gleevec) was initiated. This report adds another unique case to the growing literature on compartment syndrome in the pediatric population and reinforces the need to consider compartment syndrome, even in unlikely clinical scenarios. Copyright 2014, SLACK Incorporated.

  11. Hypothyroid-induced acute compartment syndrome in all extremities


    Musielak, Matthew C.; Chae, Jung Hee


    Acute compartment syndrome (ACS) is an uncommon complication of uncontrolled hypothyroidism. If unrecognized, this can lead to ischemia, necrosis and potential limb loss. A 49-year-old female presented with the sudden onset of bilateral lower and upper extremity swelling and pain. The lower extremity anterior compartments were painful and tense. The extensor surface of the upper extremities exhibited swelling and pain. Motor function was intact, however, limited due to pain. Bilateral lower e...

  12. Accuracy of measurement of hand compartment pressures: a cadaveric study. (United States)

    Wong, Justin C; Vosbikian, Michael M; Dwyer, Joseph M; Ilyas, Asif M


    To determine the accuracy of digital palpation for clinical assessment of elevated intracompartmental pressure compared with needle manometry in a simulated compartment syndrome of the hand. Three cadaveric hands were configured with interstitial fluid infusion and an arterial line pressure monitor to create and continuously measure intracompartmental pressure in the thenar and hypothenar compartments. Seventeen assessors clinically judged the presence or absence of compartment syndrome based on digital palpation for firmness and then measured pressures with a handheld manometer. An intracompartmental pressure threshold of 30 mm Hg or greater was used to diagnose compartment syndrome. The sensitivity and specificity of digital palpation of the thenar eminence were 49% and 79%, respectively, with a positive predictive value (PPV) of 86% and negative predictive value (NPV) of 37%. Using the handheld manometer, the sensitivity and specificity increased to 97% and 86% with a PPV of 95% and NPV of 92%. The sensitivity and specificity of digital palpation of the hypothenar eminence were 62% and 83%, respectively, with improvement of 100% and 100%, respectively, with a handheld manometer. For the hypothenar compartment, use of a handheld manometer improved the PPV from 92% to 100% and the NPV from 40% to 100% compared with digital palpation. Digital palpation alone was insufficient to detect elevated compartment pressures in hands at risk for compartment syndrome. Handheld invasive pressure measurement was a useful adjunct for detecting elevated interstitial tissue pressures and may aid in diagnosing compartment syndrome. Diagnostic II. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  13. Remote Reactor Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, Adam [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dazeley, Steve [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dobie, Doug [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Marleau, Peter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brennan, Jim [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gerling, Mark [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sumner, Matthew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sweany, Melinda [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    The overall goal of the WATCHMAN project is to experimentally demonstrate the potential of water Cerenkov antineutrino detectors as a tool for remote monitoring of nuclear reactors. In particular, the project seeks to field a large prototype gadolinium-doped, water-based antineutrino detector to demonstrate sensitivity to a power reactor at ~10 kilometer standoff using a kiloton scale detector. The technology under development, when fully realized at large scale, could provide remote near-real-time information about reactor existence and operational status for small operating nuclear reactors out to distances of many hundreds of kilometers.

  14. Development of reactor graphite (United States)

    Haag, G.; Mindermann, D.; Wilhelmi, G.; Persicke, H.; Ulsamer, W.


    The German graphite development programme for High Temperature Reactors has been based on the assumption that reactor graphite for core components with lifetime fluences of up to 4 × 10 22 neutrons per cm 2 (EDN) at 400°C can be manufactured from regular pitch coke. The use of secondary coke and vibrational moulding techniques have allowed production of materials with very small anisotropy, high strength, and high purity which are the most important properties of reactor graphite. A variety of graphite grades has been tested in fast neutron irradiation experiments. The results show that suitable graphites for modern High Temperature Reactors with spherical fuel elements are available.

  15. Oscillatory flow chemical reactors

    National Research Council Canada - National Science Library

    Slavnić Danijela S; Bugarski Branko M; Nikačević Nikola M


    .... However, the reactions of interests for the mentioned industry sectors are often slow, thus continuous tubular reactors would be impractically long for flow regimes which provide sufficient heat...

  16. Membrane reactors at Degussa. (United States)

    Wöltinger, Jens; Karau, Andreas; Leuchtenberger, Wolfgang; Drauz, Karlheinz


    The review covers the development of membrane reactor technologies at Degussa for the synthesis of fine chemicals. The operation of fed-batch or continuous biocatalytic processes in the enzyme membrane reactor (EMR) is well established at Degussa. Degussa has experience of running EMRs from laboratory gram scale up to a production scale of several hundreds of tons per year. The transfer of the enzyme membrane reactor from biocatalysis to chemical catalysis in the chemzyme membrane reactor (CMR) is discussed. Various homogeneous catalysts have been investigated in the CMR, and the scope and limitation of this new technique is discussed.

  17. Pressurizing new reactors

    Energy Technology Data Exchange (ETDEWEB)

    Neill, J.S.


    The Technical Division was asked recently to consider designs for new reactors that would add 8000 MW capacity to the Savannah River Plant. One modification of the existing SRP design that would enable a higher power rating, and therefore require fewer new reactors, is an increase in the maximum pressure in the D{sub 2}O system. The existing reactors at SRP are designed for a maximum pressure in the gas plenum of only 5 psig. Higher pressures enable higher D{sub 2} temperatures and higher sheath temperatures without local boiling or burnout. The requirements in reactor cooling facilities at any given power level would therefore be reduced by pressurizing.


    King, L.D.P.


    A homogeneous nuclear power reactor utilizing forced circulation of the liquid fuel is described. The reactor does not require fuel handling outside of the reactor vessel during any normal operation including complete shutdown to room temperature, the reactor being selfregulating under extreme operating conditions and controlled by the thermal expansion of the liquid fuel. The liquid fuel utilized is a uranium, phosphoric acid, and water solution which requires no gus exhaust system or independent gas recombining system, thereby eliminating the handling of radioiytic gas.

  19. Endoscopic Fascia Release for Forearm Chronic Exertional Compartment Syndrome: Case Report and Surgical Technique

    National Research Council Canada - National Science Library

    Miller, Elizabeth A; Cobb, Anna L; Cobb, Tyson K

    Background: Chronic exertional compartment syndrome (CECS) of the forearm is traditionally treated with open compartment release requiring large incisions that can result in less than optimal esthetic results...

  20. Compartment Syndrome of the Gluteus Medius Occurred without Bleeding or Trauma: A Case Report. (United States)

    Kong, Gyu-Min; Kwon, Yong-Uk; Park, Jun-Ho


    Compartment syndrome is an ischemic change resulting from an increase in compartment pressure. Initially, patients present with direct tenderness and swelling, and the weak circulation secondary to compartment syndrome can eventually lead to motor and sensory impairment. If the increase in pressure results in neurological impairment, emergency intervention is required to decompress the compartment. Typically, compartment syndrome develops on forearms or lower legs. The gluteal compartment is rarely the location of compartment syndrome and only a few cases have been presented in the literature with trauma or hematoma. We have treated a patient with gluteal compartment syndrome who presented with no history of trauma or hemorrhage and present that case report here.

  1. Modulatory compartments in cortex and local regulation of cholinergic tone. (United States)

    Coppola, Jennifer J; Ward, Nicholas J; Jadi, Monika P; Disney, Anita A


    Neuromodulatory signaling is generally considered broad in its impact across cortex. However, variations in the characteristics of cortical circuits may introduce regionally-specific responses to diffuse modulatory signals. Features such as patterns of axonal innervation, tissue tortuosity and molecular diffusion, effectiveness of degradation pathways, subcellular receptor localization, and patterns of receptor expression can lead to local modification of modulatory inputs. We propose that modulatory compartments exist in cortex and can be defined by variation in structural features of local circuits. Further, we argue that these compartments are responsible for local regulation of neuromodulatory tone. For the cholinergic system, these modulatory compartments are regions of cortical tissue within which signaling conditions for acetylcholine are relatively uniform, but between which signaling can vary profoundly. In the visual system, evidence for the existence of compartments indicates that cholinergic modulation likely differs across the visual pathway. We argue that the existence of these compartments calls for thinking about cholinergic modulation in terms of finer-grained control of local cortical circuits than is implied by the traditional view of this system as a diffuse modulator. Further, an understanding of modulatory compartments provides an opportunity to better understand and perhaps correct signal modifications that lead to pathological states. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Return to activity following fasciotomy for chronic exertional compartment syndrome. (United States)

    Irion, Val; Magnussen, Robert A; Miller, Timothy L; Kaeding, Christopher C


    Diagnosis of chronic exertional compartment syndrome (CECS) is relatively rare but has been well documented in athletes. There are, however, few reports regarding return to athletic activity after surgery among elite-level athletes. We hypothesized that a majority of elite-level athletes would successfully return to their previous level of competition following fasciotomy for CECS. A retrospective chart review was performed to identify elite-level athletes (collegiate or professional sport participation) who underwent fasciotomy for CECS over a 3-year period. Data collected included sport or activity, treatment and surgical details, time away from sport/activity after surgery, and ability to return to prior level of activity. Six males and seven females were included in the analysis. Patient age ranged from 17 to 24 years with a mean of 19.7 years. Six patients underwent unilateral lower extremity compartment release, and seven underwent bilateral lower extremity compartment release. The anterior and lateral compartments alone were released in 11 patients (84.6%). Two patients (15.4%) underwent four-compartment releases. Eleven patients (84.6%) were able to return to their previous elite level of sport participation at a mean of 10.6 weeks following surgical fasciotomy. Patients who had four-compartment release had a more than 3.5 week average longer return to full sporting activities (p = 0.011). Fasciotomy is effective in allowing elite athletes with CECS to return to sport.

  3. Multi-scale evaluations of submarine groundwater discharge

    Directory of Open Access Journals (Sweden)

    M. Taniguchi


    Full Text Available Multi-scale evaluations of submarine groundwater discharge (SGD have been made in Saijo, Ehime Prefecture, Shikoku Island, Japan, by using seepage meters for point scale, 222Rn tracer for point and coastal scales, and a numerical groundwater model (SEAWAT for coastal and basin scales. Daily basis temporal changes in SGD are evaluated by continuous seepage meter and 222Rn mooring measurements, and depend on sea level changes. Spatial evaluations of SGD were also made by 222Rn along the coast in July 2010 and November 2011. The area with larger 222Rn concentration during both seasons agreed well with the area with larger SGD calculated by 3D groundwater numerical simulations.

  4. Risk assessment in submarine outfall projects: the case of Portugal. (United States)

    Mendonça, Ana; Losada, Miguel Ángel; Reis, Maria Teresa; Neves, Maria Graça


    Submarine outfalls need to be evaluated as part of an integrated environmental protection system for coastal areas. Although outfalls are tight with the diversity of economic activities along a densely populated coastline being effluent treatment and effluent reuse a sign of economic prosperity, precautions must be taken in the construction of these structures. They must be designed so as to have the least possible impact on the environment and at the same time be economically viable. This paper outlines the initial phases of a risk assessment procedure for submarine outfall projects. This approach includes a cost-benefit analysis in which risks are systematically minimized or eliminated. The methods used in this study also allow for randomness and uncertainty. The input for the analysis is a wide range of information and data concerning the failure probability of outfalls and the consequences of an operational stoppage or failure. As part of this risk assessment, target design levels of reliability, functionality, and operationality were defined for the outfalls. These levels were based on an inventory of risks associated with such construction projects, and thus afforded the possibility of identifying possible failure modes. This assessment procedure was then applied to four case studies in Portugal. The results obtained were the values concerning the useful life of the outfalls at the four sites and their joint probability of failure against the principal failure modes assigned to ultimate and serviceability limit states. Also defined were the minimum operationality of these outfalls, the average number of admissible technical breakdowns, and the maximum allowed duration of a stoppage mode. It was found that these values were in consonance with the nature of the effluent (tourist-related, industrial, or mixed) as well as its importance for the local economy. Even more important, this risk assessment procedure was able to measure the impact of the outfalls on

  5. Imaging deformation in submarine thrust belts using seismic attributes (United States)

    Iacopini, David; Butler, Robert W. H.


    Uncertainty exists as to the patterns of deformation that develop within submarine thrust belts. This case study uses a large-scale gravity-driven fold-thrust structure as an analogue for submarine fold thrust systems in general. Seismic attribute analysis and mapping provide ways of identifying complex fault patterns and associated deformation that are otherwise unresolved in conventional amplitude displays. These methods are developed and applied to a 3D dataset and used to investigate the geometry, internal architecture and the nature of the low signal/noise incoherency and discontinuities observed on the km-scale. Semblance (coherency), curvatures and spectral decomposition were all computed and used as attributes. Collectively these define volumes within the seismic data where the signal is greatly reduced — features termed here "disturbance geobodies". The study shows that thrust faults that, on conventional amplitude displays appear to be simple and continuous, are likely to consist of complex arrays of anastamosing fault strands. Adjacent to these composite fault zones are greater volumes of deformed rocks (disturbance geobodies) across which there are only minor stratal offsets. Similarly volumes of high stratal curvature coincide with disturbance geobodies, again interpreted as zones of weak, distributed deformation. These relationships between narrow thrust faults and broader zones of deformation are broadly comparable to those observed in outcrops within exhumed thrust systems. Application of the seismic imaging techniques developed here will improve the understanding of the localization of deformation in sedimentary successions with important implications for predicting fluid flow within other deep water structures such as subduction accretion complexes.

  6. Geo-hazard by sediment mass movements in submarine canyons (United States)

    Ghaith, Afif; Fakhri, Milad; Ivaldi, Roberta; Ciavola, Paolo


    Submarine mass movements and their consequences are of major concern for coastal communities and infrastructures but also for the exploitation and the development of seafloor resources. Elevated awareness of the need for better understanding of the underwater mass movement is coupled with great advances in underwater mapping technologies over the past two decades. The seafloor in the Nahr Ibrahim and Saida regions (Lebanon) is characterized by deep canyons, reaching one thousand meters depths in proximity of the coast. Signs of submarine mass movement instability related to these canyons create a connection between shallow and deep water. The presence of these canyons in a tectonically active area generates a particular drained mechanism to the sediment in form of mass movement and slumping. Identification of potential areas where slope movements could be triggered requires data with high spatial resolution. Since this area is poorly explored, in the framework of an international project between Lebanese Navy, Lebanese National Center for Marine Sciences, University of Ferrara and Italian Hydrographic Institute, we analyse the morpho-bathymetric and sedimentological characters of the coastal and shelf sectors. Multibeam echosounder and sub-bottom profiler acoustic systems calibrated with ground truths (sediment grab and core samples) allow us to characterize the nature of seafloor and sub-seafloor with particular detail to the geotechnical properties of sediments and high resolution seismic stratigraphy of the shallow layers. The detection of particular undersea features provides detail maps which are in support to littoral morpho-dynamics, coastal transport and sediment budget. Multilayer hydro-oceanographic map, referring to the seafloor dynamics in connection with deep water environment and drainage system, in accordance to the International Hydrographic Standards and nautical supports, are produced. This high resolution multibeam bathymetry dataset, integrated

  7. Topology Optimization of Spacecraft Transfer Compartment

    Directory of Open Access Journals (Sweden)

    A. A. Borovikov


    Full Text Available IntroductionThe subject of this research is topology optimization of the adapter of a spacecraft transfer compartment. The finite element topology optimization [1] is widely used for simple structure elements [6, 7]. It is argued that using this method in conjunction with additive technology (3D - printing it is possible to create construction designs with the best weight characteristics. However, the paper shows that when applying this method to a complex construction design the optimization results are highly sensitive to optimization algorithm parameters. The goal of this research is to study parameters of the topology optimization algorithm and the influence of their variations on results.1.      Problem formulation   A commercial software Altair HyperWorks/OptiStruct (student’s license performed numerical calculations. The paper presents a detailed description of the finite element model.The main features of the proposed model are as follows:-          Simplicity with non-complicated geometry;-          Building a finite element model in terms of computing time minimization;-          Using the lumped mass elements to simulate the impacts of the conjugates on the adapter;-          A limit of material strength, decreased by an order of magnitude, to eliminate stress concentrators;-          The gravitational load applied corresponds to the loads for the Angara-A5 launcher [8]. 2.      Method of solutionA brief description of the SIMP-method realized in the Altair HyperWorks/OptiStruct software is given.3.      ResultsPerformed numerical calculations, and shown the influence of variations of algorithm parameters (DISCRETE, MATINIT, MINDIM, MAXDIM on construction design as well as the parameters SINGLE and SPLIT used to reveal restrictions on manufacturing.Shown that, depending on variations of parameters, an adapter construction strives to «truss» or «shell» type. Described

  8. Reactor Dosimetry State of the Art 2008 (United States)

    Voorbraak, Wim; Debarberis, Luigi; D'Hondt, Pierre; Wagemans, Jan


    from the first-generation nuclear-powered submarines by gamma scanning / A. F. Usatyi. L. A. Serdyukova and B. S. Stepennov -- Oral session 3: Power plant surveillance. Upgraded neutron dosimetry procedure for VVER-440 surveillance specimens / V. Kochkin ... [et al.]. Neutron dosimetry on the full-core first generation VVER-440 aimed to reactor support structure load evaluation / P. Borodkin ... [et al.]. Ex-vessel neutron dosimetry programs for PWRs in Korea / C. S. Yoo. B. C. Kim and C. C. Kim. Comparison of irradiation conditions of VVER-1000 reactor pressure vessel and surveillance specimens for various core loadings / V. N. Bukanov ... [et al.]. Re-evaluation of dosimetry in the new surveillance program for the Loviisa 1 VVER-440 reactor / T. Serén -- Oral session 4: Benchmarks, intercomparisons and adjustment methods. Determination of the neutron parameter's uncertainties using the stochastic methods of uncertainty propagation and analysis / G. Grégoire ... [et al.].Covariance matrices for calculated neutron spectra and measured dosimeter responses / J. G. Williams ... [et al.]. The role of dosimetry at the high flux reactor / S. C. van der Marek ... [et al.]. Calibration of a manganese bath relative to Cf-252 nu-bar / D. M. Gilliam, A. T. Yue and M. Scott Dewey. Major upgrade of the reactor dosimetry interpretation methodology used at the CEA: general principle / C. Destouches ... [et al.] -- Oral session 5: power plant surveillance. The role of ex-vessel neutron dosimetry in reactor vessel surveillance in South Korea / B.-C. Kim ... [et al.]. Spanish RPV surveillance programmes: lessons learned and current activities / A. Ballesteros and X. Jardí. Atucha I nuclear power plant extended dosimetry and assessment / H. Blaumann ... [et al.]. Monitoring of radiation load of pressure vessels of Russian VVER in compliance with license amendments / G. Borodkin ... [et al.] -- Poster session 2: Test reactors, accelerators and advanced systems; cross sections, nuclear

  9. Did a "lucky shot" sink the submarine H.L. Hunley? (United States)

    Lance, Rachel M; Warder, Henry; Bass, Cameron R Dale


    The H.L. Hunley was the first submarine to be successful in combat, sinking the Union vessel Housatonic outside Charleston Harbor in 1864 during the Civil War. However, despite marking a milestone in military history, little is known about this vessel or why it sank. One popular theory is the "lucky shot" theory: the hypothesis that small arms fire from the crew of the Housatonic may have sufficiently damaged the submarine to sink it. However, ballistic experiments with cast iron samples, analysis of historical experiments firing Civil War-era projectiles at cast iron samples, and calculation of the tidal currents and sinking trajectory of the submarine indicate that this theory is not likely. Based on our results, the "lucky shot" theory does not explain the sinking of the world's first successful combat submarine. Published by Elsevier B.V.

  10. The impact of glacier geometry on meltwater plume structure and submarine melt in Greenland fjords

    NARCIS (Netherlands)

    Carroll, D.; Sutherland, D. A.; Hudson, B.; Moon, T.; Catania, G. A.; Shroyer, E. L.; Nash, J. D.; Bartholomaus, T. C.; Felikson, D.; Stearns, L. A.; Noël, B. P Y; van den Broeke, M. R.


    Meltwater from the Greenland Ice Sheet often drains subglacially into fjords, driving upwelling plumes at glacier termini. Ocean models and observations of submarine termini suggest that plumes enhance melt and undercutting, leading to calving and potential glacier destabilization. Here we

  11. An Analysis of the Effectiveness of a New Watchstanding Schedule for U.S. Submariners

    National Research Council Canada - National Science Library

    Osborn, Christopher


    A need exists within the U.S. submarine force to employ an operational schedule that provides more sleep and that is in better alignment with human circadian rhythms, thus improving cognitive effectiveness...

  12. Fuel cell systems for submarines: from the first idea to serial production (United States)

    Psoma, Angela; Sattler, Gunter

    The future submarines of Howaldtswerke-Deutsche Werft AG (HDW) will be equipped with fuel cell power plants for air independent propulsion. In the 1970s the decision for a fuel cell system on submarines was made. Tests in the 1980s confirmed the feasibility of fuel cells on submarines. Positive development results in the 1990s led to series production of fuel cell equipped submarines, which will be in operation from 2003 onwards. Strictly controlled development work was necessary to reach the goal of series production. The train of thought behind this process of development is described in this paper starting with the initial idea and ending with the description of the serial production of the fuel cell power plant. The future outlook gives an impression of current development work.

  13. Submarine Warfare in the 20th & 21st Centuries: A Bibliography

    National Research Council Canada - National Science Library

    Huygen, Michaele


    There are constant motions in the sea caused by atmospheric and seabed activities volcanic disruptions marine animals ships and submarines -- all of which create what is called the ambient noise level of the oceans...

  14. The risk of hydrogen explosion in a submarine p. IV The implementation of high risk projects

    Directory of Open Access Journals (Sweden)

    Kłos Ryszard


    Full Text Available This series of articles on high risk projects looks at the example of the modernisation of hydrogen incinerators on a submarine. The article describes problems connected with the management of such a project.

  15. Volume transport data from a submarine cable in the Florida Strait in 2014 (NODC Accession 0125429) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily mean and raw voltage volume transport data of the Florida Current collected with a submarine cable spanning from South Florida to the Grand Bahama Island in...

  16. A Statistical Analysis of the Impact of Marital Status on Nuclear Submarine Officer Retention

    National Research Council Canada - National Science Library

    Phelps, Matthew


    This thesis develops multivariate logit models to estimate the impact of marital status and the independent effect of dependent children on nuclear submarine officer retention beyond the minimum service requirement (MSR...

  17. Observations of nearshore groundwater discharge: Kahekili Beach Park submarine springs, Maui, Hawaii

    Directory of Open Access Journals (Sweden)

    P.W. Swarzenski


    New hydrological insights for the region: Estimates of submarine groundwater discharge were derived for a primary vent site and surrounding coastal waters off west Maui, Hawaii using an excess 222Rn (t1/2 = 3.8 d mass balance model. Such estimates were complemented with a novel thoron (220Rn, t1/2 = 56 s groundwater discharge tracer application, as well as oceanographic time series and thermal infrared imagery analyses. In combination, this suite of techniques provides new insight into the connectivity of the coastal aquifer with the near-shore ocean and examines the physical drivers of submarine groundwater discharge. Lastly, submarine groundwater discharge derived constituent concentrations were tabulated and compared to surrounding seawater concentrations. Such work has implications for the management of coastal aquifers and downstream nearshore ecosystems that respond to sustained constituent loadings via this submarine route.

  18. Dance With the One That Brought You: Revitalizing Antisubmarine Warfare to Counter Chinese Diesel Submarines

    National Research Council Canada - National Science Library

    Farrell, Richard


    .... Navy needs to revitalize ASW, or risk losing the ability to gain sea control in strategic areas of the East Asian Littoral and South China Sea due to a rising Chinese diesel-electric submarine threat...

  19. Submarine Upward Looking Sonar Ice Draft Profile Data and Statistics, Version 1 (United States)

    National Aeronautics and Space Administration — This data set consists of upward looking sonar sea ice draft data collected by submarines in the Arctic Ocean. It includes data from both U.S. Navy and Royal Navy...

  20. Navy Trident Submarine Conversion (SSGN) Program: Background and Issues for Congress

    National Research Council Canada - National Science Library

    O'Rourke, Ronald


    ...) into cruisemissile- carrying and special operations forces (SOF) support submarines (SSGNs). The total estimated cost of the program, which has been increasing over time, is now $4,018 million...

  1. Technical specifications, Hanford production reactors

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, W.D. [comp.


    These technical specifications are applicable to the eight operating production reactor facilities, B, C, D, DR, F, H, KE, and KW. Covered are operating and performance restrictions and administrative procedures. Areas covered by the operating and performance restrictions are reactivity, reactor control and safety elements, power level, temperature and heat flux, reactor fuel loadings, reactor coolant systems, reactor confinement, test facilities, code compliance, and reactor scram set points. Administrative procedures include process control procedures, training programs, audits and inspections, and reports and records.

  2. Multi-core Fibers in Submarine Networks for High-Capacity Undersea Transmission Systems

    DEFF Research Database (Denmark)

    Nooruzzaman, Md; Morioka, Toshio


    Application of multi-core fibers in undersea networks for high-capacity submarine transmission systems is studied. It is demonstrated how different architectures of submerged branching unit affect network component counts in long-haul undersea transmission systems......Application of multi-core fibers in undersea networks for high-capacity submarine transmission systems is studied. It is demonstrated how different architectures of submerged branching unit affect network component counts in long-haul undersea transmission systems...

  3. They Have Not Yet Begun to Fight: Women in the United States Navy Submarine Fleet (United States)


    Navy Nurse Corps in 1908. The Nurse Corps was highly educated for the time and maintained high professional standards.3 Regardless, the struggle to...nation’s navies who integrated women into their submarine fleets ahead of the U.S. Navy. Norway, Sweden , Australian, and Great Britain all...Nations such as Norway and Sweden have been incorporating females into their submarines since the mid-1980s. 39 Sweden has had female sailors

  4. The Close Aboard Bastion: a Soviet ballistic missile submarine deployment strategy


    Kreitler, Walter M


    Approved for public release; distribution is unlimited This thesis describes and analyzes a possible deployment posture for the Soviet ballistic missile submarine force. It examines the proposition that the Soviet Navy will establish a point defense, labeled "Close Aboard Bastions" (CABs), for its ballistic missile submarine fleet within the Soviet claimed 12 nautical mile territorial sea. This is a logical derivation of the currently widely held view that the Soviets will estab...

  5. Effect of increasing nitrobenzene loading rates on the performance of anaerobic migrating blanket reactor and sequential anaerobic migrating blanket reactor/completely stirred tank reactor system

    Energy Technology Data Exchange (ETDEWEB)

    Kuscu, Ozlem Selcuk [Department of Environmental Engineering, Faculty of Engineering and Architecture, Sueleyman Demirel University, 32360, Isparta (Turkey); Sponza, Delia Teresa, E-mail: [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eyluel University, Buca Kaynaklar Campus, 35160, Izmir (Turkey)


    A laboratory scale anaerobic migrating blanket reactor (AMBR) reactor was operated at nitrobenzene (NB) loading rates increasing from 3.33 to 66.67 g NB/m{sup 3} day and at a constant hydraulic retention time (HRT) of 6 days to observe the effects of increasing NB concentrations on chemical oxygen demand (COD), NB removal efficiencies, bicarbonate alkalinity, volatile fatty acid (VFA) accumulation and methane gas percentage. Moreover, the effect of an aerobic completely stirred tank reactor (CSTR) reactor, following the anaerobic reactor, on treatment efficiencies was also investigated. Approximately 91-94% COD removal efficiencies were observed up to a NB loading rate of 30.00 g/m{sup 3} day in the AMBR reactor. The COD removal efficiencies decreased from 91% to 85% at a NB loading rate of 66.67 g/m{sup 3} day. NB removal efficiencies were approximately 100% at all NB loading rates. The maximum total gas, methane gas productions and methane percentage were found to be 4.1, 2.6 l/day and 59%, respectively, at a NB loading rate of 30.00 g/m{sup 3} day. The optimum pH values were found to be between 7.2 and 8.4 for maximum methanogenesis. The total volatile fatty acid (TVFA) concentrations in the effluent were 110 and 70 mg/l in the first and second compartments at NB loading rates as high as 66.67 and 6.67 g/m{sup 3} day, respectively, while they were measured as zero in the effluent of the AMBR reactor. In this study, from 180 mg/l NB 66 mg/l aniline was produced in the anaerobic reactor while aniline was completely removed and transformed to 2 mg/l of cathechol in the aerobic CSTR reactor. Overall COD removal efficiencies were found to be 95% and 99% for NB loading rates of 3.33 and 66.67 g/m{sup 3} day in the sequential anaerobic AMBR/aerobic CSTR reactor system, respectively. The toxicity tests performed with Photobacterium phosphoreum (LCK 480, LUMIStox) and Daphnia magna showed that the toxicity decreased with anaerobic/aerobic sequential reactor system from

  6. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E


    The activities of the Reactor Materials Research Department of the Belgian Nuclear Research Centre SCK-CEN in 2000 are summarised. The programmes within the department are focussed on studies concerning (1) fusion, in particular mechanical testing; (2) Irradiation Assisted Stress Corrosion Cracking (IASCC); (3) nuclear fuel; and (4) Reactor Pressure Vessel Steel (RPVS)

  7. Space Nuclear Reactor Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    We needed to find a space reactor concept that could be attractive to NASA for flight and proven with a rapid turnaround, low-cost nuclear test. Heat-pipe-cooled reactors coupled to Stirling engines long identified as the easiest path to near-term, low-cost concept.


    Fraas, A.P.


    A reflector for nuclear reactors that comprises an assembly of closely packed graphite rods disposed with their major axes substantially perpendicular to the interface between the reactor core and the reflector is described. Each graphite rod is round in transverse cross section at (at least) its interface end and is provided, at that end, with a coaxial, inwardly tapering hole. (AEC)

  9. Isolated Chronic Exertional Compartment Syndrome of the Lateral Lower Leg (United States)

    van Zantvoort, Aniek P.M.; de Bruijn, Johan A.; Winkes, Michiel B.; Dielemans, Jeanne P.; van der Cruijsen-Raaijmakers, Marike; Hoogeveen, Adwin R.; Scheltinga, Marc R.


    Background: Exercise-induced lower leg pain may be caused by chronic exertional compartment syndrome (CECS). The anterior (ant-CECS) or deep posterior compartment (dp-CECS) is usually affected. Knowledge regarding CECS of the lateral compartment (lat-CECS) is limited. Purpose: To describe demographic characteristics and symptoms in a consecutive series of patients with isolated CECS of the lateral compartment of the leg. Study Design: Case series; Level of evidence, 4. Methods: Since 2001, patients undergoing dynamic intracompartmental pressure (ICP) measurements for suspected CECS in a single institution were prospectively monitored. Individuals with a history possibly associated with lat-CECS and elevated ICP measurements (Pedowitz criteria) were identified. Exclusion criteria were concomitant ipsilateral ant-CECS/dp-CECS, acute compartment syndrome, recent significant trauma, peroneal nerve entrapment, or vascular claudication. Results: During an 11-year time period, a total of 26 patients with isolated lat-CECS fulfilled study criteria (15 females; median age, 21 years; range, 14-48 years). Frequently identified provocative sports were running (n = 4), walking (n = 4), field hockey (n = 3), soccer (n = 3), and volleyball (n = 2). Exercise-induced lateral lower leg pain (92%) and tightness (42%) were often reported. The syndrome was bilateral in almost two-thirds (62%, n = 16). Delay in diagnosis averaged 24 months (range, 2 months to 10 years). Conclusion: Young patients with exercise-induced pain in the lateral portions of the lower leg may suffer from isolated CECS of the lateral compartment. ICP measurements in the lateral compartment in these patients are recommended. PMID:26740955

  10. Outcome of a Specific Compartment Fasciotomy Versus a Complete Compartment Fasciotomy of the Leg in One Patient With Bilateral Anterior Chronic Exertional Compartment Syndrome: A Case Report. (United States)

    Tjeerdsma, Jason


    Chronic exertional compartment syndrome of the leg is a debilitating lower extremity condition in which increased intracompartmental pressure impedes blood flow to the involved compartments of the distal lower extremity, resulting in ischemia and pain. Owing to the lack of success with conservative management, most surgeons perform complete release fasciotomy as the preferred method of fasciotomy to avoid an unsuccessful release or outcome. Studies have been performed regarding the outcomes of complete compartmental release versus specific compartmental release, but no study has been performed comparing complete fasciotomy and compartment-specific fasciotomy in a single patient. The purpose of the present case report was to compare the efficacy of a complete fasciotomy versus a specific fasciotomy in 1 patient with properly diagnosed bilateral anterior compartment chronic exertional compartment syndrome with an 18-month follow-up period. The Lower Extremity Functional Scale and both subscales of the Foot and Ankle Ability Measure were administered to assess the functional outcomes. Circumferential measurements and range of motion photographs were taken to compare the objective data throughout the recovery process. In general, the range of motion, circumferential measurements, and functional outcome measure scores were better for the specific compartmental fasciotomy leg than for the complete fasciotomy leg during the recovery period. The overall functional outcomes were the same for both surgical approaches, with the specific fasciotomy leg returning to baseline function 13 to 23 days before the complete fasciotomy leg. The outcomes remained unchanged 18 months after surgery. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  11. Mirror reactor surface study

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A. L.; Damm, C. C.; Futch, A. H.; Hiskes, J. R.; Meisenheimer, R. G.; Moir, R. W.; Simonen, T. C.; Stallard, B. W.; Taylor, C. E.


    A general survey is presented of surface-related phenomena associated with the following mirror reactor elements: plasma first wall, ion sources, neutral beams, director converters, vacuum systems, and plasma diagnostics. A discussion of surface phenomena in possible abnormal reactor operation is included. Several studies which appear to merit immediate attention and which are essential to the development of mirror reactors are abstracted from the list of recommended areas for surface work. The appendix contains a discussion of the fundamentals of particle/surface interactions. The interactions surveyed are backscattering, thermal desorption, sputtering, diffusion, particle ranges in solids, and surface spectroscopic methods. A bibliography lists references in a number of categories pertinent to mirror reactors. Several complete published and unpublished reports on surface aspects of current mirror plasma experiments and reactor developments are also included.

  12. Nuclear reactor design

    CERN Document Server


    This book focuses on core design and methods for design and analysis. It is based on advances made in nuclear power utilization and computational methods over the past 40 years, covering core design of boiling water reactors and pressurized water reactors, as well as fast reactors and high-temperature gas-cooled reactors. The objectives of this book are to help graduate and advanced undergraduate students to understand core design and analysis, and to serve as a background reference for engineers actively working in light water reactors. Methodologies for core design and analysis, together with physical descriptions, are emphasized. The book also covers coupled thermal hydraulic core calculations, plant dynamics, and safety analysis, allowing readers to understand core design in relation to plant control and safety.

  13. Status of French reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ballagny, A. [Commissariat a l`Energie Atomique, Saclay (France)


    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  14. Submarine channel evolution linked to rising salt domes, Gulf of Mexico, USA (United States)

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


    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.

  15. Observations of nearshore groundwater discharge: Kahekili Beach Park submarine springs, Maui, Hawaii (United States)

    Swarzenski, Peter W.; Dulai, H.; Kroeger, K.D.; Smith, C.G.; Dimova, N.; Storlazzi, C. D.; Prouty, N.G.; Gingerich, S.B.; Glenn, C. R.


    Study regionThe study region encompasses the nearshore, coastal waters off west Maui, Hawaii. Here abundant groundwater—that carries with it a strong land-based fingerprint—discharges into the coastal waters and over a coral reef.Study focusCoastal groundwater discharge is a ubiquitous hydrologic feature that has been shown to impact nearshore ecosystems and material budgets. A unique combined geochemical tracer and oceanographic time-series study addressed rates and oceanic forcings of submarine groundwater discharge at a submarine spring site off west Maui, Hawaii.New hydrological insights for the regionEstimates of submarine groundwater discharge were derived for a primary vent site and surrounding coastal waters off west Maui, Hawaii using an excess 222Rn (t1/2 = 3.8 d) mass balance model. Such estimates were complemented with a novel thoron (220Rn,t1/2 = 56 s) groundwater discharge tracer application, as well as oceanographic time series and thermal infrared imagery analyses. In combination, this suite of techniques provides new insight into the connectivity of the coastal aquifer with the near-shore ocean and examines the physical drivers of submarine groundwater discharge. Lastly, submarine groundwater discharge derived constituent concentrations were tabulated and compared to surrounding seawater concentrations. Such work has implications for the management of coastal aquifers and downstream nearshore ecosystems that respond to sustained constituent loadings via this submarine route.

  16. Surgical Treatment of Chronic Exertional Compartment Syndrome in Pediatric Patients. (United States)

    Beck, Jennifer J; Tepolt, Frances A; Miller, Patricia E; Micheli, Lyle J; Kocher, Mininder S


    Chronic exertional compartment syndrome (CECS) is a cause of leg pain in running athletes and is treated with fasciotomy after failure of nonoperative management. CECS is being seen with increased frequency in younger patients. The demographics and outcomes of fasciotomy for CECS in pediatric patients, including risk factors for treatment failure, have not been described. To describe characteristics of pediatric patients with CECS and determine surgical outcomes of the condition in this population. Case series; Level of evidence, 4. A retrospective review was performed for patients 18 years and younger treated surgically for CECS with compartment release at a single institution from 1995 to 2014. Demographic and condition characteristics, operative procedure, postoperative course, and clinical outcomes were recorded for 286 legs of 155 patients. Compartment pressure testing using the Pedowitz criteria confirmed the diagnosis in all patients. A total of 155 patients were included in the study (average patient age at presentation, 16.4 ± 1.38 years); 136 (88%) were female. All 155 patients presented with leg pain; of these patients, 8 (5%) also had neurologic symptoms, and 131 (85%) presented with bilateral symptoms requiring bilateral compartment release. Symptoms were chronic in nature, with duration over 1 year in 63% of patients. The primary sport was most commonly reported as running (25%), soccer (23%), or field hockey (12%); 50% of patients were multisport athletes. Of 286 legs, 138 (48%) had only anterior and/or lateral compartments released, while 84 (29.4%) had all 4 compartments released. Documented return to sport was seen in 79.5% of patients. Outcomes analysis was performed for 250 of 286 legs. Of these 250 legs, 47 (18.8%) had recurrent CECS requiring reoperation at a median of 1.3 years (interquartile range, 0.8-3.5) after initial compartment release. For each additional month between presentation and release, the odds of recurrence decreased by 12

  17. New semi-pilot-scale reactor to study the photocatalytic inactivation of phages contained in aerosol. (United States)

    Briggiler Marcó, Mariángeles; Negro, Antonio Carlos; Alfano, Orlando Mario; Quiberoni, Andrea Del Luján


    The aims of this work were to design and build a photocatalytic reactor (UV-A/TiO 2 ) to study the inactivation of phages contained in bioaerosols, which constitute the main dissemination via phages in industrial environments. The reactor is a close system with recirculation that consists of a stainless steel camera (cubic form, side of 60 cm) in which air containing the phage particles circulates and an acrylic compartment with six borosilicate plates covered with TiO 2 . The reactor is externally illuminated by 20 UV-A lamps. Both compartments are connected by a fan to facilitate the sample circulation. Samples are injected into the camera using two piston nebulizers working in series whereas several methodologies for sampling (impinger/syringe, sampling on photocatalytic plates, and impact of air on slide) were assayed. The reactor setup was carried out using phage B1 (Lactobacillus plantarum), and assays demonstrated a decrease of phage counts of 2.7 log orders after 1 h of photocatalytic treatment. Photonic efficiencies of inactivation were assessed by phage sampling on the photocatalytic plates or by impact of air on a glass slide at the photocatalytic reactor exit. Efficiencies of the same order of magnitude were observed using both sampling methods. This study demonstrated that the designed photocatalytic reactor is effective to inactivate phage B1 (Lb. plantarum) contained in bioaerosols.

  18. Implementation of the environmental management plan for the dismantling of nuclear powered submarines at Zvezdochka shipyard, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Washer, M. [Dept. of Foreign Affairs and International Trade, Ontario (Canada); Cull, M.; Crocker, C. [Teledyne Brown Engineering Limited, Arlington, Virginia (United States); Ivanov, V.; Shepurev, A. [FSUE Zvezdochka, Arkhangelsk region, Severodvinsk (Russian Federation); Khan, B.U.Z.; Lee, M.; Gerchikov, M. [Nuclear Safety Solutions Limited, Toronto, Ontario (Canada)


    Department of Foreign Affairs and International Trade Canada is funding the dismantling of twelve nuclear powered submarines (NPS) from the Russian Federation's Northern Fleet as part of the Global Partnership Initiative against weapons and materials of mass destruction. In this paper, work performed by Nuclear Safety Solutions Ltd. and its collaborators in support of these activities is described. First, an environmental impact assessment of towing and dismantling NPS in the Kola Peninsula, and the Barents and White Seas was performed. The assessed activities included: towing of NPS from Naval Bases in Murmansk Region to the Zvezdochka shipyard (Severodvinsk); defuelling of onboard reactors; dismantling of NPS at Zvezdochka; and waste management. The assessment helped identify mitigation measures that could prevent the occurrence of adverse effects. Next, the project team defined and implemented an environmental management plan (EMP) based on the shipyard's existing environmental policy and the mitigating measures identified during the environmental assessment. Specific targets were defined to track the progress of the EMP implementation, and are described in this paper. During the study period, three Victor Class NPS were dismantled at Zvezdochka. The major benefits realized include: removal of spent nuclear fuel assemblies; treatment/ decontamination of liquid and solid radioactive waste; and the cultivation of collaboration between Russian and Western expertise. (author)

  19. Implementation of the environmental management plan for the dismantling of nuclear powered submarines at Zvezdochka Shipyard, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Washer, M. [Dept. of Foreign Affairs and International Trade, Ottawa, Ontario (Canada); Cull, M.; Crocker, C. [Teledyne Brown Engineering Limited, Arlington, Virginia (United States); Ivanov, V.; Shepurev, A. [FSUE Zvezdochka, Arkhangelsk region, Severodvinsk (Russian Federation); Khan, B.U.Z.; Lee, M.; Gerchikov, M. [Nuclear Safety Solutions Limited, Toronto, Ontario (Canada)


    Department of Foreign Affairs and International Trade Canada is funding the dismantling of twelve nuclear powered submarines (NPS) from the Russian Federation's Northern Fleet as part of the Global Partnership Initiative against weapons and materials of mass destruction. In this paper, work performed by Nuclear Safety Solutions Ltd. and its collaborators in support of these activities is described. First, an environmental impact assessment of towing and dismantling NPS in the Kola Peninsula, and the Barents and White Seas was performed. The assessed activities included: towing of NPS from Naval Bases in Murmansk Region to the Zvezdochka shipyard (Severodvinsk); defuelling of onboard reactors; dismantling of NPS at Zvezdochka; and waste management. The assessment helped identify mitigation measures that could prevent the occurrence of adverse effects. Next, the project team defined and implemented an environmental management plan (EMP) based on the shipyard's existing environmental policy and the mitigating measures identified during the environmental assessment. Specific targets were defined to track the progress of the EMP implementation, and are described in this paper. During the study period, three Victor Class NPS were dismantled at Zvezdochka. The major benefits realized include: removal and spent nuclear fuel assemblies; treatment/decontamination of liquid and solid radioactive waste; and the cultivation of collaboration between Russian and Western expertise. (author)

  20. Membrane order in the plasma membrane and endocytic recycling compartment. (United States)

    Iaea, David B; Maxfield, Frederick R


    The cholesterol content of membranes plays an important role in organizing membranes for signal transduction and protein trafficking as well as in modulating the biophysical properties of membranes. While the properties of model or isolated membranes have been extensively studied, there has been little evaluation of internal membranes in living cells. Here, we use a Nile Red based probe, NR12S, and ratiometric live cell imaging, to analyze the membrane order of the plasma membrane and endocytic recycling compartment. We find that after a brief incubation to allow endocytosis, NR12S is distributed between the plasma membrane and the endocytic recycling compartment. The NR12S reports that the endocytic recycling compartment is more highly ordered than the plasma membrane. We also find that the plasma membrane and the endocytic recycling compartment are differentially affected by altering cellular cholesterol levels. The membrane order of the plasma membrane, but not the endocytic recycling compartment, is altered significantly when cellular cholesterol content is increased or decreased by 20%. These results demonstrate that changes in cellular cholesterol differentially alter membrane order within different organelles.

  1. Elevated compartment pressures from copperhead envenomation successfully treated with antivenin. (United States)

    Mazer-Amirshahi, Maryann; Boutsikaris, Amy; Clancy, Cathleen


    Copperhead envenomation causes local soft tissue effects; however, associated compartment syndrome is rare. We report a case of a 17-month-old with significantly elevated compartment pressures successfully treated with antivenin and supportive care. A 17-month-old girl sustained a copperhead bite to the foot and presented with circumferential edema, erythema, and ecchymosis of the foot and distal ankle. The patient had palpable pulses and was neurologically intact. Four vials of Crotalidae polyvalent immune Fab was initiated and additional doses were administered in an attempt to achieve local control. Within 10 h of presentation, the patient's edema extended to the groin, although sensation was maintained and pulses were documented by Doppler. Lower-extremity compartment pressures were measured and were most notable for an anterior pressure of 85 mm Hg, despite having received 12 vials of antivenin. Fasciotomy was deferred and the patient received two additional six-vial doses of antivenin to achieve local control. Compartment pressures improved with a 2.2-cm mean decrease in limb diameter within 48 h. Maintenance dosing was initiated and the patient ultimately received a total of 26 vials of antivenin. The patient did not develop significant coagulopathy or thrombocytopenia. Swelling continued to improve with return of limb function. In this case, early and aggressive treatment with antivenin may have avoided invasive fasciotomy, and its use should be considered in patients with copperhead envenomation and significantly elevated compartment pressures. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Numerical modelling of crural fascia mechanical interaction with muscular compartments. (United States)

    Pavan, Piero G; Pachera, Paola; Natali, Arturo N


    The interaction of the crural fascia with muscular compartments and surrounding tissues can be at the origin of different pathologies, such as compartment syndrome. This pathology consists in the onset of excessive intracompartmental pressure, which can have serious consequences for the patient, compromising blood circulation. The investigation of compartment syndrome etiology also takes into account the alteration of crural fascia mechanical properties as a cause of the syndrome, where the fascial stiffening would result in the rise of intracompartmental pressure. This work presents a computational approach toward evaluating some biomechanical aspects of the problem, within the context of a more global viewpoint. Finite element analyses of the interaction phenomena of the crural fascia with adjacent regions are reported here. This study includes the effects of a fascial stiffness increase along the proximal-distal direction and their possible clinical implications. Furthermore, the relationship between different pre-strain levels of the crural fascia in the proximal-distal direction and the rise of internal pressure in muscular compartments are considered. The numerical analyses can clarify which aspects could be directly implied in the rise of compartment syndrome, leading to greater insight into muscle-fascia mechanical phenomena, as well as promoting experimental investigation and clinical analysis of the syndrome. © IMechE 2015.

  3. Measurement of compartment elasticity using pressure related ultrasound: a method to identify patients with potential compartment syndrome. (United States)

    Sellei, R M; Hingmann, S J; Kobbe, P; Weber, C; Grice, J E; Zimmerman, F; Jeromin, S; Gansslen, A; Hildebrand, F; Pape, H C


    PURPOSE OF THE STUDY Decision-making in treatment of an acute compartment syndrome is based on clinical assessment, supported by invasive monitoring. Thus, evolving compartment syndrome may require repeated pressure measurements. In suspected cases of potential compartment syndromes clinical assessment alone seems to be unreliable. The objective of this study was to investigate the feasibility of a non-invasive application estimating whole compartmental elasticity by ultrasound, which may improve accuracy of diagnostics. MATERIAL AND METHODS In an in-vitro model, using an artificial container simulating dimensions of the human anterior tibial compartment, intracompartmental pressures (p) were raised subsequently up to 80 mm Hg by infusion of saline solution. The compartmental depth (mm) in the cross-section view was measured before and after manual probe compression (100 mm Hg) upon the surface resulting in a linear compartmental displacement (Δd). This was repeated at rising compartmental pressures. The resulting displacements were related to the corresponding intra-compartmental pressures simulated in our model. A hypothesized relationship between pressures related compartmental displacement and the elasticity at elevated compartment pressures was investigated. RESULTS With rising compartmental pressures, a non-linear, reciprocal proportional relation between the displacement (mm) and the intra-compartmental pressure (mm Hg) occurred. The Pearson's coefficient showed a high correlation (r2 = -0.960). The intraobserver reliability value kappa resulted in a statistically high reliability (κ = 0.840). The inter-observer value indicated a fair reliability (κ = 0.640). CONCLUSIONS Our model reveals that a strong correlation between compartmental strain displacements assessed by ultrasound and the intra-compartmental pressure changes occurs. Further studies are required to prove whether this assessment is transferable to human muscle tissue. Determining the complete

  4. Lead-Cooled Fast Reactor (LFR) Design: Safety, Neutronics, Thermal Hydraulics, Structural Mechanics, Fuel, Core, and Plant Design

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C


    The idea of developing fast spectrum reactors with molten lead (or lead alloy) as a coolant is not a new one. Although initially considered in the West in the 1950s, such technology was not pursued to completion because of anticipated difficulties associated with the corrosive nature of these coolant materials. However, in the Soviet Union, such technology was actively pursued during the same time frame (1950s through the 1980s) for the specialized role of submarine propulsion. More recently, there has been a renewal of interest in the West for such technology, both for critical systems as well as for Accelerator Driven Subcritical (ADS) systems. Meanwhile, interest in the former Soviet Union, primarily Russia, has remained strong and has expanded well beyond the original limited mission of submarine propulsion. This section reviews the past and current status of LFR development.

  5. Nuclear reactor control column (United States)

    Bachovchin, Dennis M.


    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest cross-sectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

  6. Reactor Safety Research Programs

    Energy Technology Data Exchange (ETDEWEB)

    Edler, S. K.


    This document summarizes the work performed by Pacific Northwest Laboratory (PNL) from January 1 through March 31, 1981, for the Division of Reactor Safety Research within the U.S. Nuclear Regulatory Commission (NRC). Evaluations of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibility of determining the strength of structural graphite, evaluating the feasibility of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the integrity of pressurized water reactor (PWR) steam generator tubes where service-induced degradation has been indicated. Experimental data and analytical models are being provided to aid in decision-making regarding pipeto- pipe impacts following postulated breaks in high-energy fluid system piping. Core thermal models are being developed to provide better digital codes to compute the behavior of full-scale reactor systems under postulated accident conditions. Fuel assemblies and analytical support are being provided for experimental programs at other facilities. These programs include loss-ofcoolant accident (LOCA) simulation tests at the NRU reactor, Chalk River, Canada; fuel rod deformation, severe fuel damage, and postaccident coolability tests for the ESSOR reactor Super Sara Test Program, Ispra, Italy; the instrumented fuel assembly irradiation program at Halden, Norway; and experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory (INEL). These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

  7. Reactor power monitoring device

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Naotaka; Igawa, Shinji; Kitazono, Hideaki


    The present invention provides a reactor power monitoring device capable of ensuring circumstance resistance, high reliability and high speed transmission even if an APRM is disposed in a reactor building (R/B). Namely, signal processing sections (APRM) for transmitting data to a central control chamber are distributed in the reactor building at an area at the lowest temperature among areas where the temperature control in an emergency state is regulated, and a transmission processing section (APRM-I/F) for transmitting data to the other systems is disposed to the central control chamber. An LPRM signal transmission processing section is constituted such that LPRM signals can be transmitted at a high speed by DMA. Set values relevant to reactor tripping (neutron flux high, thermal output high and sudden reduction of a reactor core flow rate) are stored in the APRM-I/F, and reactor tripping calculation is conducted in the APRM-I/F. With such procedure, a reactor power monitoring device having enhanced control function can be attained. (N.H.)

  8. Experimental modeling of gravity underflow in submarine channels (United States)

    Islam, Mohammad Ashraful

    Active and relic meandering channels are common on the seafloor adjacent to continental margins. These channels and their associated submarine fan deposits are products of the density-driven gravity flows known as turbidity currents. Unlike natural rivers, few attempts have been made to explore the process of channel meandering in the submarine environment. This research focuses on resolving the flow field of submarine channels by conducting experiments in a large laboratory basin. Saline and particulate density flows were studied in a straight channel, a single bend sinuous channel with vertical sidewalls and a multiple-bend sinuous channel with sloping sidewalls. Instantaneous velocities in steady developed currents were measured using 3-component acoustic Doppler velocity probes. Excess fractional density was measured at selected locations by collecting water sample using a siphon rake. Turbulent kinetic energy and Reynolds stress components are derived from the instantaneous velocity data of the straight channel experiments. Structure functions for mean velocity, Reynolds stress and turbulent kinetic energy profiles are derived by fitting normalized data. The normalized Reynolds-averaged velocity shows excellent similarity collapse while the Reynolds-stress and the turbulent kinetic energy profiles display reasonable similarity. Vertical profiles of the turbulent kinetic energy display two peaks separated by a zone of low turbulence; the ratio of the maximum to the depth-averaged turbulent kinetic energy is approximately 1.5. Theoretical profile of turbulent kinetic energy is derived. Comparisons of experimentally and theoretically derived turbulent kinetic energy profiles show reasonable agreement except at the position of velocity maximum where the theoretical profile displays a very small value. Velocity profiles derived from the measurements with confined flow in the single bend channel reveal that channel curvature drives two helical flow cells, one

  9. Long-term flow monitoring of submarine gas emanations (United States)

    Spickenbom, K.; Faber, E.; Poggenburg, J.; Seeger, C.


    One of the Carbon Capture and Storage (CCS) strategies currently under study is the sequestration of CO2 in sub-seabed geological formations. Even after a thorough review of the geological setting, there is the possibility of leaks from the reservoirs. As part of the EU-financed project CO2ReMoVe (Research, Monitoring, Verification), which aims to develop innovative research and technologies for monitoring and verification of carbon dioxide geological storage, we are working on the development of submarine long-term gas flow monitoring systems. Technically, however, these systems are not limited to CO2 but can be used for monitoring of any free gas emission (bubbles) on the seafloor. The basic design of the gas flow sensor system was derived from former prototypes developed for monitoring CO2 and CH4 on mud volcanoes in Azerbaijan. This design was composed of a raft floating on the surface above the gas vent to collect the bubbles. Sensors for CO2 flux and concentration and electronics for data storage and transmission were mounted on the raft, together with battery-buffered solar panels for power supply. The system was modified for installation in open sea by using a buoy instead of a raft and a funnel on the seafloor to collect the gas, which is then guided above water level through a flexible tube. Besides some technical problems (condensed water in the tube, movement of the buoys due to waves leading to biased measurement of flow rates), this setup provides a cost-effective solution for shallow waters. However, a buoy interferes with ship traffic, and it is also difficult to adapt this design to greater water depths. These requirements can best be complied by a completely submersed system. To allow unattended long-term monitoring in a submarine environment, such a system has to be extremely durable. Therefore, we focussed on developing a mechanically and electrically as simple setup as possible, which has the additional advantage of low cost. The system

  10. Well-leg compartment syndrome after gynecological laparoscopic surgery

    DEFF Research Database (Denmark)

    Boesgaard-Kjer, Diana H; Boesgaard-Kjer, Daniel; Kjer, Jens Jørgen


    Well-leg compartment syndrome in the lower extremities after surgery in the lithotomy position is a rare but severe complication requiring early diagnosis and intervention. Several circumstances predispose to this condition as a consequence of increased intra-compartmental pressure......, such as positioning of the legs during operation (lithotomy and Lloyd-Davies positions), a prolonged operation, external compression and vascular insults, both pre- and intra-operatively. To prevent well-leg compartment syndrome it is important to improve knowledge of the condition among surgeons and nursing staff....... Potential risk factors and preventive initiatives are listed to reduce the risk in future patients. We describe two patients who underwent gynecologic laparoscopic surgery and postoperatively developed well-leg compartment syndrome....

  11. Acute Compartment Syndrome of the Limbs: Current Concepts and Management (United States)

    Mabvuure, Nigel Tapiwa; Malahias, Marco; Hindocha, Sandip; Khan, Wasim; Juma, Ali


    Acute compartment syndrome (ACS) of the limb refers to a constellation of symptoms, which occur following a rise in the pressure inside a limb muscle compartment. A failure or delay in recognising ACS almost invariably results in adverse outcomes for patients. Unrecognised ACS can leave patients with nonviable limbs requiring amputation and can also be life–threatening. Several clinical features indicate ACS. Where diagnosis is unclear there are several techniques for measuring intracompartmental pressure described in this review. As early diagnosis and fasciotomy are known to be the best determinants of good outcomes, it is important that surgeons are aware of the features that make this diagnosis likely. This clinical review discusses current knowledge on the relevant clinical anatomy, aetiology, pathophysiology, risk factors, clinical features, diagnostic procedures and management of an acute presentation of compartment syndrome. PMID:23248724

  12. Exercise Induced Rhabdomyolysis with Compartment Syndrome and Renal Failure

    Directory of Open Access Journals (Sweden)

    Mary Colleen Bhalla


    Full Text Available Exertional rhabdomyolysis is sequela that is occasionally seen after strenuous exercise. The progression to compartment syndrome or renal failure is a rare complication that requires prompt recognition and treatment to prevent morbidity (Giannoglou et al. 2007. We present a case of a 22-year-old college football player who presented to the emergency department (ED after a typical leg workout as part of his weight conditioning. He was found to have rhabdomyolysis with evidence of renal insufficiency. His condition progressed to bilateral compartment syndrome and renal failure requiring dialysis. After bilateral fasciotomies were performed he had resolution of his compartment syndrome. He continued to be dialysis dependent and had no return of his renal function at discharge 12 days after admission.

  13. Nuclear reactor reflector (United States)

    Hopkins, R.J.; Land, J.T.; Misvel, M.C.


    A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled. 12 figs.

  14. Fast Breeder Reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.


    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  15. Reactor flux calculations

    Energy Technology Data Exchange (ETDEWEB)

    Lhuillier, D. [Commissariat à l' Énergie Atomique et aux Énergies Alternatives, Centre de Saclay, IRFU/SPhN, 91191 Gif-sur-Yvette (France)


    The status of the prediction of reactor anti-neutrino spectra is presented. The most accurate method is still the conversion of total β spectra of fissionning isotopes as measured at research reactors. Recent re-evaluations of the conversion process led to an increased predicted flux by few percent and were at the origin of the so-called reactor anomaly. The up to date predictions are presented with their main sources of error. Perspectives are given on the complementary ab-initio predictions and upcoming experimental cross-checks of the predicted spectrum shape.


    Metcalf, H.E.


    Methods of controlling reactors are presented. Specifically, a plurality of neutron absorber members are adjustably disposed in the reactor core at different distances from the center thereof. The absorber members extend into the core from opposite faces thereof and are operated by motive means coupled in a manner to simultaneously withdraw at least one of the absorber members while inserting one of the other absorber members. This feature effects fine control of the neutron reproduction ratio by varying the total volume of the reactor effective in developing the neutronic reaction.

  17. Nuclear reactor reflector (United States)

    Hopkins, Ronald J.; Land, John T.; Misvel, Michael C.


    A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled.

  18. Microfluidic electrochemical reactors (United States)

    Nuzzo, Ralph G [Champaign, IL; Mitrovski, Svetlana M [Urbana, IL


    A microfluidic electrochemical reactor includes an electrode and one or more microfluidic channels on the electrode, where the microfluidic channels are covered with a membrane containing a gas permeable polymer. The distance between the electrode and the membrane is less than 500 micrometers. The microfluidic electrochemical reactor can provide for increased reaction rates in electrochemical reactions using a gaseous reactant, as compared to conventional electrochemical cells. Microfluidic electrochemical reactors can be incorporated into devices for applications such as fuel cells, electrochemical analysis, microfluidic actuation, pH gradient formation.

  19. Using Google Earth for Submarine Operations at Pavilion Lake (United States)

    Deans, M. C.; Lees, D. S.; Fong, T.; Lim, D. S.


    During the July 2009 Pavilion Lake field test, we supported submarine "flight" operations using Google Earth. The Intelligent Robotics Group at NASA Ames has experience with ground data systems for NASA missions, earth analog field tests, disaster response, and the Gigapan camera system. Leveraging this expertise and existing software, we put together a set of tools to support sub tracking and mapping, called the "Surface Data System." This system supports flight planning, real time flight operations, and post-flight analysis. For planning, we make overlays of the regional bedrock geology, sonar bathymetry, and sonar backscatter maps that show geology, depth, and structure of the bottom. Placemarks show the mooring locations for start and end points. Flight plans are shown as polylines with icons for waypoints. Flight tracks and imagery from previous field seasons are embedded in the map for planning follow-on activities. These data provide context for flight planning. During flights, sub position is updated every 5 seconds from the nav computer on the chase boat. We periodically update tracking KML files and refresh them with network links. A sub icon shows current location of the sub. A compass rose shows bearings to indicate heading to the next waypoint. A "Science Stenographer" listens on the voice loop and transcribes significant observations in real time. Observations called up to the surface immediately appear on the map as icons with date, time, position, and what was said. After each flight, the science back room immediately has the flight track and georeferenced notes from the pilots. We add additional information in post-processing. The submarines record video continuously, with "event" timestamps marked by the pilot. We cross-correlate the event timestamps with position logs to geolocate events and put a preview image and compressed video clip into the map. Animated flight tracks are also generated, showing timestamped position and providing timelapse

  20. Did a submarine landslide contribute to the 2011 Tohoku tsunami?

    KAUST Repository

    Tappin, David R.


    Many studies have modeled the Tohoku tsunami of March 11, 2011 as being due entirely to slip on an earthquake fault, but the following discrepancies suggest that further research is warranted. (1) Published models of tsunami propagation and coastal impact underpredict the observed runup heights of up to 40 m measured along the coast of the Sanriku district in the northeast part of Honshu Island. (2) Published models cannot reproduce the timing and high-frequency content of tsunami waves recorded at three nearshore buoys off Sanriku, nor the timing and dispersion properties of the waveforms at offshore DART buoy #21418. (3) The rupture centroids obtained by tsunami inversions are biased about 60 km NNE of that obtained by the Global CMT Project. Based on an analysis of seismic and geodetic data, together with recorded tsunami waveforms, we propose that, while the primary source of the tsunami was the vertical displacement of the seafloor due to the earthquake, an additional tsunami source is also required. We infer the location of the proposed additional source based on an analysis of the travel times of higher-frequency tsunami waves observed at nearshore buoys. We further propose that the most likely additional tsunami source was a submarine mass failure (SMF—i.e., a submarine landslide). A comparison of pre- and post-tsunami bathymetric surveys reveals tens of meters of vertical seafloor movement at the proposed SMF location, and a slope stability analysis confirms that the horizontal acceleration from the earthquake was sufficient to trigger an SMF. Forward modeling of the tsunami generated by a combination of the earthquake and the SMF reproduces the recorded on-, near- and offshore tsunami observations well, particularly the high-frequency component of the tsunami waves off Sanriku, which were not well simulated by previous models. The conclusion that a significant part of the 2011 Tohoku tsunami was generated by an SMF source has important implications for

  1. Acute and recurrent effort-related compartment syndrome in sports. (United States)

    Martens, M A; Moeyersoons, J P


    An effort-related compartmental syndrome is a condition in which increased pressure in a muscle compartment impedes blood flow and compromises metabolic demands of the tissues within that space. One can clinically distinguish acute irreversible and chronic reversible types. The aetiology relates in most instances to a limiting noncompliant fascia surrounding the affected muscle compartment. Sports activity leads to increased muscle volume and if there is a noncompliant fascia this will result in an excessive intracompartmental pressure which interferes with muscle blood flow. As a consequence of a reduced intracompartmental blood flow a reversible (recurrent) or irreversible (acute) exercise ischaemia, a so-called 'compartmental syndrome' occurs. A compartment syndrome is typically encountered in the lower leg, but it can be also observed in the upper leg and even in the forearm. Clinical history plays a key role in the diagnosis. Pain, muscle tightness and cramp-like feeling are the most common complaints. Weakness, paralysis and numbness are seen, especially in the acute syndrome. Symptoms appear at a certain intensity of activity and disappear at rest in the chronic compartment syndrome, but in the acute type pain will persist and will be severe. It is clearly an effort-related pain syndrome. Physical examination is not always useful in diagnosing a recurrent syndrome, but in the acute syndrome one will find high sensitivity to pressure and tenseness over the involved muscle compartment. Decreased or loss of active motion and sensation in the involved compartment are frequently seen. Tissue pressure monitoring can confirm the diagnosis for both types.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Complications After Fasciotomy Revision and Delayed Compartment Release in Combat Patients (United States)


    were three carpal tunnels , one forearm flexor compartment, one triceps compartment, and one hypothenar compartment. Of the 51 patients, who under- went...anatomy making fas- ciotomies challenging. Rapid air evacua- tion may delay treatment of patients with evolving extremity compartment syndrome . We...of major amputa- tion and a threefold higher mortality. Key Words: Fasciotomy, Compart- ment syndrome , Extremity, Revision, De- layed, Combat wounds

  3. Acute compartment syndrome of the thigh in a rugby player (United States)

    Smith, Richard David James; Rust-March, Holly; Kluzek, Stefan


    In the absence of obvious trauma, diagnosis of acute compartment syndrome (ACS) of the thigh can easily be delayed, as disproportional pain is not always present. We present a case of ACS of the anterior right thigh compartment in a healthy, semiprofessional rugby player with normal coagulation, who sustained a seemingly innocuous blow during a rugby match. Following early surgical fasciotomy, he returned to his preinjury playing standards within 12 months. Our literature review suggests that high muscle mass, young, athletic males participating in a contact sport are mostly at risk of developing ACS of the thigh. PMID:26250368

  4. New reactor type proposed

    CERN Multimedia


    "Russian scientists at the Research Institute of Nuclear Power Engineering in Moscow are hoping to develop a new reactor that will use lead and bismuth as fuel instead of uranium and plutonium" (1/2 page).

  5. Preliminary study on aerobic granular biomass formation with aerobic continuous flow reactor (United States)

    Yulianto, Andik; Soewondo, Prayatni; Handajani, Marissa; Ariesyady, Herto Dwi


    A paradigm shift in waste processing is done to obtain additional benefits from treated wastewater. By using the appropriate processing, wastewater can be turned into a resource. The use of aerobic granular biomass (AGB) can be used for such purposes, particularly for the processing of nutrients in wastewater. During this time, the use of AGB for processing nutrients more reactors based on a Sequencing Batch Reactor (SBR). Studies on the use of SBR Reactor for AGB demonstrate satisfactory performance in both formation and use. SBR reactor with AGB also has been applied on a full scale. However, the use use of SBR reactor still posses some problems, such as the need for additional buffer tank and the change of operation mode from conventional activated sludge to SBR. This gives room for further reactor research with the use of a different type, one of which is a continuous reactor. The purpose of this study is to compare AGB formation using continuous reactor and SBR with same operation parameter. Operation parameter are Organic Loading Rate (OLR) set to 2,5 Kg COD/ with acetate as substrate, aeration rate 3 L/min, and microorganism from Hospital WWTP as microbial source. SBR use two column reactor with volumes 2 m3, and continuous reactor uses continuous airlift reactor, with two compartments and working volume of 5 L. Results from preliminary research shows that although the optimum results are not yet obtained, AGB can be formed on the continuous reactor. When compared with AGB generated by SBR, then the characteristics of granular diameter showed similarities, while the sedimentation rate and Sludge Volume Index (SVI) characteristics showed lower yields.

  6. Potential Impact of Atmospheric Releases at Russian Far East Nuclear Submarine Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Parker, F.; Mahura, A.; Compton, K.; Brown, K.; Takano, M.; Novikov, V.; Soerensen, J. H.; Baklanov, A.


    An ''Assessment of the Impact of Russian Nuclear Fleet Operations on Far Eastern Coastal Regions'' is being performed as part of the Radiation Safety of the Biosphere Project (RAD) of the International Institute for Applied Systems Analysis (IIASA) of Laxenburg, Austria. To the best of our knowledge, this is the first comprehensive unclassified analysis of the potential impact of accidents at the Russian Far East nuclear submarine sites near Vladivostok and Petropavlovsk. We have defined the situation there based upon available information and studies commissioned by RAD in collaboration with Russian research institutes including Russian Research Center-''Kurchatov Institute'', Institute of Northern Environmental Problems and Lazurit Central Design Bureau. Further, in our original work, some in collaboration with the staff of the Danish Meteorological Institute (DMI) and members of the Japan Atomic Energy Research Institute, we have calculated the nuclide trajectories from these sites in the atmospheric boundary layer, less than 1.5 kilometers high, and determined their probability of crossing any of the nearby countries as well as Asiatic Russia. We have further determined the concentrations in each of these crossings as well as the total, dry and wet depositions of nuclides on these areas. Finally, we have calculated the doses to the Japanese Island population from typical winter airflow patterns (those most likely to cross the Islands in the minimum times), strong north winds, weak north winds and cyclonic winds for conditions similar to the Chazhma Bay criticality accident (fresh fuel) and for a criticality accident for the same type of reactor with fuel being withdrawn (spent fuel). The maximum individual committed dosages were less than 2 x 10-7 and 2 x 10-3 mSv, respectively. The long-term external doses by radionuclides deposited on the ground and the internal doses by consumption of foods were not evaluated as it is

  7. Performance of an Anaerobic Baffled Filter Reactor in the Treatment of Algae-Laden Water and the Contribution of Granular Sludge

    Directory of Open Access Journals (Sweden)

    Yaqin Yu


    Full Text Available This study investigated the performance and stability of an anaerobic baffled filter reactor in the treatment of algae-laden water from Taihu Lake at several organic loading rates. The study also evaluated the capability of soft filler to train granule sludge and improve the anaerobic environment and sludge activity in the anaerobic baffled reactor (ABR, thereby enhancing the treatment efficiency. The ABR consisted of five rectangular compartments, each of which was 120 cm long, 80 cm wide, 80 cm high, and packed with soft filler. The anaerobic baffled filter reactor was found to be an efficient reactor configuration for the treatment of algae-laden water. The reactor was operated at an organic loading rate of 1.5 kg chemical oxygen demand (COD/(m3d and an ambient temperature of 30 °C; under these conditions, the COD removal efficiency was 80% and the biogas production rate was 293 mL/(Ld. Moreover, the soft filler increased the biomass retention time and decreased the rate at which solids were washed out from the reactor, promoting an improved spatial distribution of the microbial communities within the compartments. Methanoregula, Methanobacteriaceae, Methanosaeta, Methanoculleu, and Thermogymnomonas were the dominant archaeal species in each compartment during an operational period of approximately 100 days. The protease activity in the reactor decreased longitudinally down the reactor from Compartments 1 to 5, whereas the activity of coenzyme F420 increased. The soft filler played a key role in successfully treating algae-laden water with the anaerobic baffled filter reactor.

  8. Submarine pyroclastic deposits in Tertiary basins, NE Slovenia

    Directory of Open Access Journals (Sweden)

    Polona Kralj


    Full Text Available In Tertiary basins of NE Slovenia, Upper Oligocene volcanic activity occurred in a submarine environment that experienced contemporaneous clastic sedimentation. Pyroclastic deposits are essentially related to gas- and watersupported eruption-fed density currents. At Trobni Dol, the Lako Basin, an over 100 m thick deposit formed by a sigle sustained volcanic explosion that fed gas-supported pyroclastic flow. Diagnostic features are large matrixshard content, normal grading of pumice lapilli, collapsed pumice lapilli and the presence of charcoal. In the Smrekovec Volcanic Complex, several but only up to 5 m thick deposits related to eruption-fed gassupported pyroclastic flows occur. Deposits settled from water-supported eruption-fed density currents form fining- and thinning-upward sedimentary units which resemble the units of volcaniclastic turbidites. Pyroclastic deposits related to gas- and water-supported density currents occur in an up to 1000 m thick succession composed of coherent volcanics, autoclastic, pyroclastic, reworked volcaniclastic and mixed volcaniclastic-siliciclastic deposits that indicate a complex explosive and depositional history of the Smrekovec Volcanic Complex.

  9. Breathing modes of Kolumbo submarine volcano (Santorini, Greece). (United States)

    Bakalis, Evangelos; Mertzimekis, Theo J; Nomikou, Paraskevi; Zerbetto, Francesco


    Submarine volcanoes, such as Kolumbo (Santorini, Greece) are natural laboratories for fostering multidisciplinary studies. Their investigation requires the most innovative marine technology together with advanced data analysis. Conductivity and temperature of seawater were recorded directly above Kolumbo's hydrothermal vent system. The respective time series have been analyzed in terms of non-equilibrium techniques. The energy dissipation of the volcanic activity is monitored by the temperature variations of seawater. The venting dynamics of chemical products is monitored by water conductivity. The analysis of the time series in terms of stochastic processes delivers scaling exponents with turning points between consecutive regimes for both conductivity and temperature. Changes of conductivity are shown to behave as a universal multifractal and their variance is subdiffusive as the scaling exponents indicate. Temperature is constant over volcanic rest periods and a universal multifractal behavior describes its changes in line with a subdiffusive character otherwise. The universal multifractal description illustrates the presence of non-conservative conductivity and temperature fields showing that the system never retains a real equilibrium state. The existence of a repeated pattern of the combined effect of both seawater and volcanic activity is predicted. The findings can shed light on the dynamics of chemical products emitted from the vents and point to the presence of underlying mechanisms that govern potentially hazardous, underwater volcanic environments.

  10. High-efficiency airfoil rudders applied to submarines

    Directory of Open Access Journals (Sweden)

    ZHOU Yimei


    Full Text Available Modern submarine design puts forward higher and higher requirements for control surfaces, and this creates a requirement for designers to constantly innovate new types of rudder so as to improve the efficiency of control surfaces. Adopting the high-efficiency airfoil rudder is one of the most effective measures for improving the efficiency of control surfaces. In this paper, we put forward an optimization method for a high-efficiency airfoil rudder on the basis of a comparative analysis of the various strengths and weaknesses of the airfoil, and the numerical calculation method is adopted to analyze the influence rule of the hydrodynamic characteristics and wake field by using the high-efficiency airfoil rudder and the conventional NACA rudder comparatively; at the same time, a model load test in a towing tank was carried out, and the test results and simulation calculation obtained good consistency:the error between them was less than 10%. The experimental results show that the steerage of a high-efficiency airfoil rudder is increased by more than 40% when compared with the conventional rudder, but the total resistance is close:the error is no more than 4%. Adopting a high-efficiency airfoil rudder brings much greater lifting efficiency than the total resistance of the boat. The results show that high-efficiency airfoil rudder has obvious advantages for improving the efficiency of control, giving it good application prospects.

  11. Submarine springs and coastal karst aquifers: A review (United States)

    Fleury, Perrine; Bakalowicz, Michel; de Marsily, Ghislain


    SummaryThis article reports on current knowledge of coastal karst aquifers, in which conduit flow is dominant, and its aim is to characterise the functioning of these systems which are closely linked to the sea. First, earlier and recent studies of these aquifers are discussed. On the basis of their findings, it can be shown that two essential mechanisms are involved in the functioning of these systems, i.e., aquifer discharge through submarine springs and saline intrusion through conduits open to the sea. Then, the conditions that give rise to these aquifers are described and particular emphasis is placed on the influence of deep karstification when the sea level falls. The base-level variations are attributed to the glaciations or, in the specific case of the Mediterranean, to the salinity crisis in the Messinian period. It is this inherited structure, sometimes containing very deep conduits below sea level, that today conditions the aquifer flow. The flow in the conduits open to the sea depends on the hydraulic head gradient between the aquifer and the sea and is therefore a function of the water density and head losses in the aquifer. This survey of coastal karst aquifers has revealed some common characteristics that show the development and/or functional capacity of their karstic drainage networks. A classification of such systems into three categories is proposed with the aim of assisting in the decision-making concerning potential exploitation of water resources in coastal regions.

  12. Sea-level-induced seismicity and submarine landslide occurrence (United States)

    Brothers, Daniel S.; Luttrell, Karen M.; Chaytor, Jason D.


    The temporal coincidence between rapid late Pleistocene sea-level rise and large-scale slope failures is widely documented. Nevertheless, the physical mechanisms that link these phenomena are poorly understood, particularly along nonglaciated margins. Here we investigate the causal relationships between rapid sea-level rise, flexural stress loading, and increased seismicity rates along passive margins. We find that Coulomb failure stress across fault systems of passive continental margins may have increased more than 1 MPa during rapid late Pleistocene–early Holocene sea-level rise, an amount sufficient to trigger fault reactivation and rupture. These results suggest that sea-level–modulated seismicity may have contributed to a number of poorly understood but widely observed phenomena, including (1) increased frequency of large-scale submarine landslides during rapid, late Pleistocene sea-level rise; (2) emplacement of coarse-grained mass transport deposits on deep-sea fans during the early stages of marine transgression; and (3) the unroofing and release of methane gas sequestered in continental slope sediments.

  13. NESTOR - Neutrino Extended Submarine Telescope with Oceanographic Research

    CERN Document Server


    {\\bf NESTOR} is a deep-sea neutrino telescope that is being deployed in the Mediterranean off the south-west coast of the Peleponnese in Greece. Neutrinos, when they interact in the earth below or in the seawater around the detector, produce muons that can be observed by the Cherenkov radiation, which they emit. At an operating depth of 4000 metres, the detector is effectively shielded from muons produced in atmospheric interactions. {\\bf The site:} A major feature of the Ionian Sea floor is the Hellenic Trench, the deepest in the Mediterranean, which in places exceeds 5000 meters. It runs close to the western coast of the Peleponnese and is protected on its western side by the submarine Eastern Mediterranean Ridge. It is far from big city pollution or the effluent of major river systems flowing into the Mediterranean and is protected from deep-water perturbations.\\\\ The NESTOR site is located on a broad plateau some 8 $\\times$ 9 kilometres in area on the eastern side of the Hellenic Trench at a mean depth of...

  14. Ecostructuring of marine nematode communities by submarine groundwater discharge. (United States)

    Grzelak, Katarzyna; Tamborski, Joseph; Kotwicki, Lech; Bokuniewicz, Henry


    Inputs of submarine groundwater discharge (SGD) to the coastal ocean may alter local and regional-scale biology. Here, we report on nematode assemblages along the north shore of Long Island, NY. We test if nematode communities differed between sites impacted by mixed fresh-saline SGD and where SGD is exclusively saline. Diversity of nematodes was low at sites impacted by fresh SGD and communities were dominated by a few opportunistic genera. Moreover, a set of typical freshwater nematode genera restricted to impacted sites was observed. Their presence in the marine coastal zone is exceptional and underlines the structuring role that fresh SGD plays in the local ecosystem. Saline SGD structured nematode assemblages differently compared to sites impacted by fresh SGD. The number of nematode genera was markedly higher at saline SGD sites, with a different community structure. This study highlights the importance to which inputs of fresh SGD may have on local ecosystem diversity in marine coastal environments. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Breathing modes of Kolumbo submarine volcano (Santorini, Greece) (United States)

    Bakalis, Evangelos; Mertzimekis, Theo J.; Nomikou, Paraskevi; Zerbetto, Francesco


    Submarine volcanoes, such as Kolumbo (Santorini, Greece) are natural laboratories for fostering multidisciplinary studies. Their investigation requires the most innovative marine technology together with advanced data analysis. Conductivity and temperature of seawater were recorded directly above Kolumbo’s hydrothermal vent system. The respective time series have been analyzed in terms of non-equilibrium techniques. The energy dissipation of the volcanic activity is monitored by the temperature variations of seawater. The venting dynamics of chemical products is monitored by water conductivity. The analysis of the time series in terms of stochastic processes delivers scaling exponents with turning points between consecutive regimes for both conductivity and temperature. Changes of conductivity are shown to behave as a universal multifractal and their variance is subdiffusive as the scaling exponents indicate. Temperature is constant over volcanic rest periods and a universal multifractal behavior describes its changes in line with a subdiffusive character otherwise. The universal multifractal description illustrates the presence of non-conservative conductivity and temperature fields showing that the system never retains a real equilibrium state. The existence of a repeated pattern of the combined effect of both seawater and volcanic activity is predicted. The findings can shed light on the dynamics of chemical products emitted from the vents and point to the presence of underlying mechanisms that govern potentially hazardous, underwater volcanic environments.

  16. Department of Reactor Technology

    DEFF Research Database (Denmark)

    Risø National Laboratory, Roskilde

    The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included.......The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included....

  17. High Efficiency Nuclear Power Plants Using Liquid Fluoride Thorium Reactor Technology (United States)

    Juhasz, Albert J.; Rarick, Richard A.; Rangarajan, Rajmohan


    An overall system analysis approach is used to propose potential conceptual designs of advanced terrestrial nuclear power plants based on Oak Ridge National Laboratory (ORNL) Molten Salt Reactor (MSR) experience and utilizing Closed Cycle Gas Turbine (CCGT) thermal-to-electric energy conversion technology. In particular conceptual designs for an advanced 1 GWe power plant with turbine reheat and compressor intercooling at a 950 K turbine inlet temperature (TIT), as well as near term 100 MWe demonstration plants with TITs of 950 and 1200 K are presented. Power plant performance data were obtained for TITs ranging from 650 to 1300 K by use of a Closed Brayton Cycle (CBC) systems code which considered the interaction between major sub-systems, including the Liquid Fluoride Thorium Reactor (LFTR), heat source and heat sink heat exchangers, turbo-generator machinery, and an electric power generation and transmission system. Optional off-shore submarine installation of the power plant is a major consideration.

  18. Natural convection reactor

    Energy Technology Data Exchange (ETDEWEB)

    Babcock, D.F.; Bernath, L.; Menegus, R.L.; Ring, H.F.


    A previous report described the conceptual design of a plutonium producing reactor that may be characterized as follows: Power output (2000 MW); cooling - (natural convection of light water through the reactor, up through a draft tube to an evaporative cooling pond, then back to the reactor, and fuel (400 to 500 tons of uranium enriched to 1.2% U-235). Because this reactor would be cooled by the natural convection of light water, it is believed that the construction costs would be significantly less than for a Savannah or Hanford type reactor. Such expensive items as water treatment and water pumping facilities would be eliminated entirely. The inventory of 500 tons of slightly enriched uranium, however, is an unattractive feature. It represents not only a large dollar investment but also makes the reactor less attractive for construction during periods of national emergency because of the almost certain scarcity of even slightly enriched uranium at that time. The Atomic Energy Commission asked that the design be reviewed with the objective of reducing the inventory of uranium, The results of this review are given in this report.

  19. Performance of staged and non-staged up-flow anaerobic sludge bed (USSB and UASB) reactors treating low strength complex wastewater. (United States)

    Sevilla-Espinosa, Susana; Solórzano-Campo, Maricela; Bello-Mendoza, Ricardo


    The use of anaerobic processes to treat low-strength wastewater has been increasing in recent years due to their favourable performance-costs balance. For optimal results, it is necessary to identify reactor configurations that are best suited for this kind of application. This paper reports on the comparative study carried out with two high-rate anaerobic reactor systems with the objective of evaluating their performances when used for the treatment of low-strength, complex wastewater. One of the systems is the commonly used up-flow anaerobic sludge blanket (UASB) reactor. The other is the up-flow staged sludge bed (USSB) system in which the reactor was divided longitudinally into 3, 5 and 7 compartments by the use of baffles. The reactors (9 l) were fed with a synthetic, soluble and colloidal waste (chemical oxygen demand (COD) flow hydraulics, between plug-flow and completely-mixed, in the UASB and 7 stages USSB reactors allowed efficient degradation of substrates with minimum effluent concentrations. Low number of compartments in the USSB reactors increased the levels of short-circuiting thus reducing substrate removal efficiencies. All reactors showed high COD removal efficiencies (93-98%) and thus can be regarded as suitable for the treatment of low strength, complex wastewater. Staged anaerobic reactors can be a good alternative for this kind of application provided they are fitted with a large enough (> or =7) number of compartments to fully take advantage of their strengths. Scale factors seem to have influenced importantly on the comparison between one and multi staged sludge-bed reactors and, therefore, observations made here could change at larger reactor volumes.

  20. The Enemy Below - The Global Diffusion of Submarines and Related Technology

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, K G


    The end of the Cold War seemed to create a more peaceful international environment. September 11 reminded us of the dangers of complacency. Indeed, even before September 11 US forces had intervened in a number of wars and crises, including Panama, the Persian Gulf War, Somalia, Rwanda, Bosnia, Kosovo, several Taiwan Straits crises, the North Korea nuclear weapons crisis, and most recently Afghanistan. US ability to intervene in remote areas of the world is often dependent on the Navy's ability to project power ashore. As a result, US ability to influence events in crisis situations, especially between or among nuclear powers, may become more difficult along with our ability to conduct littoral warfare. Although the numbers of potentially hostile submarines have declined with the end of the Cold War, US anti-submarine warfare capabilities have also declined. Moreover, foreign submarines and related technologies are likely to diffuse globally. New technologies like Air Independent Propulsion (AIP), improved weapons and sensors will make conventional submarines more dangerous, and the spread of nuclear submarines even to a few more countries raise political, military, environmental, and safety concerns. Submarines are one of the key weapon systems used alone or in combination with other weapon systems such as coastal defense missiles, aircraft, and other sea-based missile platforms to deny US ability to project power ashore, Thus, other countries who wish to deny the US the ability to interfere with their regional or even global ambitions may emphasize the acquisition and/or development of submarines. As the world become more multipolar over the longer term, as the Chinese believe it will, countries such as Russia, China. etc., may be able to acquire the submarine capabilities to challenge us not just regionally, but in blue waters. To the extent that our alliance relationships require US naval access or superiority to sustain them, then our erstwhile friendly

  1. 19 CFR 123.24 - Sealing of conveyances or compartments. (United States)


    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Sealing of conveyances or compartments. 123.24 Section 123.24 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY CUSTOMS RELATIONS WITH CANADA AND MEXICO Shipments in Transit Through Canada or...

  2. Surgical treatment for ~brain compartment syndrome' in children ...

    African Journals Online (AJOL)

    Objectives. Traumatic brain injury accounts for a high percentage of deaths in children. Raised intracranial pressure (ICP) due to brain swelling within the closed compartment of the skull leads to death or severe neurological disability if not effectively treated. We report our experience with 12 children who presented with ...

  3. Ward Round - Late Presentation of Acute Compartment Syndrome in ...

    African Journals Online (AJOL)

    following the course of ibuprofen mentioned. Twelve days after admission he started to complain of increasing pain and tightness in his left thigh. Sensation and motor function. Ward Round - Late Presentation of Acute. Compartment Syndrome in the Thigh. University of Malawi, College of Medicine, Department of Surgery,.

  4. latrogenic chronic compartment syndrome of leg due to ruptured ...

    African Journals Online (AJOL)

    A 45 year old male complaining of chronic pain and swelling of his left calf with features suggestive of chronic compartment syndrome following therapeutic aspiration of a popliteal cyst has been presented. It is a rare type of presentation which has not been reported to the knowledge of the authors. Review of literature and

  5. 9 CFR 354.241 - Cleaning of rooms and compartments. (United States)


    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Cleaning of rooms and compartments. 354.241 Section 354.241 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... Sanitary Conditions and Precautions Against Contamination of Products § 354.241 Cleaning of rooms and...

  6. Compartment syndrome and popliteal vascular injury complicating unicompartmental knee arthroplasty

    NARCIS (Netherlands)

    Kort, Nanne Pieter; Van Raay, Jos J. J. A. M.; van Horn, Jim R.

    Popliteal vascular injury and the compartment syndrome of the leg are rare but important complications of knee arthroplasties. Early diagnosis and treatment are of paramount importance in preventing the devastating complications of these conditions. To our knowledge, these complications have not

  7. Abdominal Compartment Syndrome in Acute Pancreatitis : A Systematic Review

    NARCIS (Netherlands)

    van Brunschot, Sandra; Schut, Anne Julia; Bouwense, Stefan A.; Besselink, Marc G.; Bakker, Olaf J.; Goor ,van Harry; Hofker, Hendrik; Gooszen, Hein G.; Boermeester, Marja A.; van Santvoort, Hjalmar C.

    Abdominal compartment syndrome (ACS) is a lethal complication of acute pancreatitis. We performed a systematic review to assess the treatment and outcome of these patients. A systematic literature search for cohorts of patients with acute pancreatitis and ACS was performed. The main outcomes were

  8. Abdominal compartment syndrome in acute pancreatitis: a systematic review

    NARCIS (Netherlands)

    van Brunschot, Sandra; Schut, Anne Julia; Bouwense, Stefan A.; Besselink, Marc G.; Bakker, Olaf J.; van Goor, Harry; Hofker, Sijbrand; Gooszen, Hein G.; Boermeester, Marja A.; van Santvoort, Hjalmar C.


    Abdominal compartment syndrome (ACS) is a lethal complication of acute pancreatitis. We performed a systematic review to assess the treatment and outcome of these patients.A systematic literature search for cohorts of patients with acute pancreatitis and ACS was performed. The main outcomes were

  9. "Compartment"-syndrom på underben, atypisk traumemekanisme

    DEFF Research Database (Denmark)

    Larsen, Michael H; Nielsen, Henrik Toft; Wester, Jens Ulrik


    Acute compartment syndrome (CS) is a limb threatening condition which warrants emergency treatment. We describe a case of a 37-year-old man with acute CS developed without major trauma. Early diagnosis and prompt treatment by decompressive fasciotomy is of vital importance in order to preserve limb...

  10. The abdominal compartment syndrome : A complication with many faces

    NARCIS (Netherlands)

    Berger, P.; Nijsten, MWN; Paling, JC; Zwaveling, JH

    Background: Lately renewed attention has been given to the abdominal compartment syndrome. Despite of this there still remain a lot of controversies with regard to the pathophysiological mechanisms underlying this syndrome and the therapeutic options. Methods: Two cases of patients with this

  11. Acute compartment syndrome of the thigh without associated ...

    African Journals Online (AJOL)

    Acute compartment syndrome of the thigh is a rare complication of trauma to the thigh. It occurs less commonly than in other sites such as the leg and forearm. Because of its rarity, it is often not suspected and its diagnosis is frequently delayed with disastrous consequences. We report a patient who sustained blunt trauma to ...

  12. 14 CFR 125.167 - Extinguishing agent container compartment temperature. (United States)


    ... temperature. 125.167 Section 125.167 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Requirements § 125.167 Extinguishing agent container compartment temperature. Precautions must be taken to ensure that the extinguishing agent containers are installed in places where reasonable temperatures can...

  13. 14 CFR 121.269 - Extinguishing agent container compartment temperature. (United States)


    ... temperature. 121.269 Section 121.269 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF....269 Extinguishing agent container compartment temperature. Precautions must be taken to insure that the extinguishing agent containers are installed in places where reasonable temperatures can be...

  14. 46 CFR 169.625 - Compartments containing diesel machinery. (United States)


    ...-cooled propulsion and auxiliary engines installed below deck must be fitted with air intake ducts or... arrangement including air intakes, exhaust stack, method of attachment of ventilation ducts to the engine... mechanical supply and exhaust ventilation. One duct must extend to a point near the bottom of the compartment...

  15. 14 CFR 23.853 - Passenger and crew compartment interiors. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Passenger and crew compartment interiors. 23.853 Section 23.853 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... instruments in a common housing, seatbelts, shoulder harnesses, and cargo and baggage tiedown equipment...

  16. A wolf in wolf's clothing the abdominal compartment syndrome

    African Journals Online (AJOL)

    A wolf in wolf's clothing the abdominal compartment syndrome. R. Burrows, J. Edington, J. V. Robbs. Four patients are described in whom massive abdominal distension after laparotomy led to ... abdominal surgery or trauma may not be a prerequisite for ... high peak airway pressure and high CVP, although urine output and ...

  17. The abdominal compartment syndrome (ACS) in general surgery. (United States)

    Bodnár, Zsolt; Sipka, Sándor; Hajdu, Zoltán


    The abdominal compartment syndrome is a life threatening clinical entity which can develop within the first 12 hours of intensive care unit admission in high-risk surgical patients. The aim of this paper is to show the definitions, ethiology, pathophysiology, diagnosis and treatment of this serious, not only surgical problem. The mortality due to the abdominal compartment syndrome is extremely high (38-71%). It can be defined as adverse physiologic consequences that occur as a result of an acute increase in the intraabdominal pressure. The most common causes are retroperitoneal haemorrhage, visceral oedema, pancreatitis, bowel obstruction, tense ascites, peritonitis, tumor. The mostly affected systems are cardiovascular, pulmonary, renal, central nervous systems and splanchnic organs. The gold standard diagnostic method is the continuous intra-abdominal pressure monitoring. The treatment consists of adequate fluid resuscitation and surgical decompression. We show three typical short case reports treated by the above mentioned theories. Intraabdominal hypertension and abdominal compartment syndrome are frequent clinical findings among acute general surgical patients. Patients with comparable demographics and acute severity of illness are more likely to die if intraabdominal hypertension or abdominal compartment syndrome is present. We conclude that the early recognition and surgical decompression is urgent.

  18. The compartmented alginate fibres optimisation for bitumen rejuvenator encapsulation

    Directory of Open Access Journals (Sweden)

    Amir Tabaković


    Full Text Available This article presents development of a novel self-healing technology for asphalt pavements, where asphalt binder rejuvenator is encapsulated within the compartmented alginate fibres. The key objective of the study was to optimise the compartmented alginate fibre design, i.e., maximising amount of rejuvenator encapsulated within the fibre. The results demonstrate that optimum rejuvenator content in the alginate fibre is of 70:30 rejuvenator/alginate ratio. The fibres are of sufficient thermal and mechanical strength to survive harsh asphalt mixing and compaction processes. Furthermore, results illustrate that zeer open asfalt beton (ZOAB asphalt mix containing 5% of 70:30 rejuvenator/alginate ratio compartmented alginate fibres has higher strength, stiffness and better healing properties in comparison to the control asphalt mix, i.e., mix without fibres, and mix containing fibres with lower rejuvenator content. These results show that compartmented alginate fibres encapsulating bitumen rejuvenator present a promising new approach for the development of self-healing asphalt pavement systems.

  19. Chronic exertional compartment syndrome in the forearm of a rower ...

    African Journals Online (AJOL)

    This case report describes chronic exertional compartment syndrome in the forearm of a professional rower. We consider this to be a rare anatomical location for this type of syndrome. Morever, not much is known about its clinical presentation and the subsequent optimal medical management thereof.

  20. 14 CFR 25.773 - Pilot compartment view. (United States)


    ...) Internal windshield and window fogging. The airplane must have a means to prevent fogging of the internal... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Personnel and Cargo Accommodations... limitations of the airplane, including taxiing takeoff, approach, and landing. (2) Each pilot compartment must...

  1. Compartment specific importance of glutathione during abiotic and biotic stress

    Directory of Open Access Journals (Sweden)

    Bernd eZechmann


    Full Text Available The tripeptide thiol glutathione (γ-L-glutamyl-L-cysteinyl-glycine is the most important sulfur containing antioxidant in plants and essential for plant defense against abiotic and biotic stress conditions. It is involved in the detoxification of reactive oxygen species, redox signaling, the modulation of defense gene expression and important for the regulation of enzymatic activities. Even though changes in glutathione contents are well documented in plants and its roles in plant defense are well established, still too little is known about its compartment specific importance during abiotic and biotic stress conditions. Due to technical advances in the visualization of glutathione and the redox state of plants through microscopical methods some progress was made in the last few years in studying the importance of subcellular glutathione contents during stress conditions in plants. This review summarizes the data available on compartment specific importance of glutathione in the protection against abiotic and biotic stress conditions such as high light stress, exposure to cadmium, drought, and pathogen attack (Pseudomonas, Botrytis, Tobacco Mosaic Virus. The data will be discussed in connection with the subcellular accumulation of ROS during these conditions and glutathione synthesis which are both highly compartment specific (e.g. glutathione synthesis takes place in chloroplasts and the cytosol. Thus this review will reveal the compartment specific importance of glutathione during abiotic and biotic stress conditions.

  2. Gluteal Compartment Syndrome following an Iliac Bone Marrow Aspiration

    Directory of Open Access Journals (Sweden)

    Edmundo Berumen-Nafarrate


    Full Text Available The compartment syndrome is a condition characterized by a raised hydraulic pressure within a closed and non expandable anatomical space. It leads to a vascular insufficiency that becomes critical once the vascular flow cannot return the fluids back to the venous system. This causes a potential irreversible damage of the contents of the compartment, especially within the muscle tissues. Gluteal compartment syndrome (GCS secondary to hematomas is seldom reported. Here we present a case of a 51-year-old patient with history of a non-Hodgkin lymphoma who underwent a bone marrow aspiration from the posterior iliac crest that had excessive bleeding at the puncture zone. The patient complained of increasing pain, tenderness, and buttock swelling. Intraoperative pressure validation of the gluteal compartment was performed, and a GCS was diagnosed. The patient was treated with a gluteal region fasciotomy. The patient recovered from pain and swelling and was discharged shortly after from the hospital. We believe clotting and hematologic disorders are a primary risk factor in patients who require bone marrow aspirations or biopsies. It is important to improve awareness of GCS in order to achieve early diagnosis, avoid complications, and have a better prognosis.

  3. Awolf in wolf's clothing the abdominal compartment syndrome ...

    African Journals Online (AJOL)

    All cases were associated with massive fluid resuscitation and operative findings were a grossly oedematous bowel with free fluid under pressure in the abdomen. These findings are consistent with the diagnosis of intra-abdominal compartment syndrome. In 1 case trauma was remote from the abdomen indicating that ...

  4. Westward advance of the deformation front and evolution of submarine canyons offshore of southwestern Taiwan (United States)

    Han, Wei-Chung; Liu, Char-Shine; Chi, Wu-Cheng; Chen, Liwen; Lin, Che-Chuan; Chen, Song-Chuen


    This study analyzes both 2D and 3D seismic images around the Palm Ridge area offshore of southwestern Taiwan to understand how the deformation front shifted westward and how tectonic activities interact with submarine canyon paths in the transition area between the active and passive margins. Palm Ridge is a submarine ridge that developed on the passive China continental margin by down-dip erosion of several tributaries of Penghu Canyon; it extends eastward across the deformation front into the submarine Taiwan accretionary wedge. The presence of proto-thrusts that are located west of the frontal thrust implies that the compressional stress field has advanced westward due to the convergence of the Philippine Sea Plate and Eurasian Plate. Since the deformation front is defined as the location of the most frontal contractional structure, no significant contractional structure should appear west of it. We thus suggest moving the location of the previously mapped deformation front farther west to where the westernmost proto-thrust lies. High-resolution seismic and bathymetric data reveal that the directions of the paleo-submarine canyons run transverse to the present slope dip, while the present submarine canyons head down slope in the study area. We propose that this might be the result of the westward migration of the deformation front that changed the paleo-bathymetry and thus the canyon path directions. The interactions of down-slope processes and active tectonics control the canyon paths in our study area.

  5. Influence of stiffness constant of stern bearing on vibration and acoustic radiation of whole submarine

    Directory of Open Access Journals (Sweden)

    WANG Lucai


    Full Text Available [Objectives] This paper studies the influence of the stiffness constant of a stern bearing on the vibration and acoustic radiation of a whole submarine.[Methods] Based on the form of SUBOFF, a whole submarine model is established in which the structures of the propeller and shaft are first formed in solid elements. Through calculating and comparing the structural vibration and acoustic radiation driven by a vertically excited force, the influence of the elastic coefficient of the stern bearing on the vibroacoustic of the overall submarine structure is mainly considered. [Results] It is demonstrated that the reduction of the elastic coefficient of the stern bearing leads to the convergence of structural vibration and acoustic radiation to the second order overall bending modal frequency, and the frequency gradually becomes lower, which can benefit the vibroacoustic reduction of submarines at frequencies higher than the second order overall bending modal frequency. [Conclusions] These results provide a reference for the acoustic design of submarine structures.

  6. Methane concentration inside a submarine mud volcano examined through seismic velocity profiles (United States)

    Kioka, Arata; Tsuji, Takeshi; Otsuka, Hironori; Ashi, Juichiro


    Mud volcanoes are considered to be among largest geological sources releasing hydrocarbon gases into the atmosphere. Numerous studies have revealed their origins and compositions from submarine mud volcanoes. A recent long-term observation at a submarine mud volcano sheds light on that larger volume of methane gas than expected is escaped from deep-water mud volcanoes, suggesting that the global methane flux from the seafloor is likely underestimated. Yet, estimates of the gas amount inside mud volcanoes have been still challenging, because of the difficulty of in-situ measurements. This study provides a new model to bridge methane amounts and seismic velocities in fluidized mud conduits of submarine mud volcanoes. This model is universally applicable and enables estimates of methane concentration in the mud conduits, using the seismic velocity profile derived from reflection/refraction seismic and/or downhole logging data. In this study, (1) we examine our modeled results through deep-drilling data obtained at mud volcanoes in the Olimpi mud field of the central Mediterranean Ridge accretionary margin, to evaluate the difference between in situ methane amounts and those calculated from our model, and (2) apply our model to the seismic velocity profile derived from seicmic data to estimate the methane amount inside the submarine mud volcano in the Nankai accretionary margin. Our scheme may provide an opportunity to re-estimate the total methane flux from submarine mud volcanoes.

  7. Compartment syndrome of the thigh: a systematic review. (United States)

    Ojike, Nwakile I; Roberts, Craig S; Giannoudis, Peter V


    Thigh compartment syndrome is a surgical emergency with risk of high morbidity and mortality rates. The purpose of this study was to review the available evidence regarding the causes of thigh compartment syndrome, techniques of fasciotomy (specifically, one versus two incisions), methods of wound closure, and complications. This institutional review board-exempt study was performed at a level-one trauma centre. PubMed and Medline OVID databases in the English language were searched for case series of two or more cases of compartment syndrome of the thigh. Cases were reviewed and analysed for causes of thigh compartment syndrome, number of fasciotomy incisions, methods of wound closure, and complications. A total of 9 papers met our criteria. All were retrospective case studies comprising a total of 89 patients. The most common cause was blunt trauma (90%). Motor vehicle accidents accounted for 36% of cases whilst motorcycle accidents were involved in 9%. Associated injuries included femur fractures in 48%, other limb fractures, renal, cardiovascular and head insults. Eighty-six percent of fasciotomies were performed through a single incision. Fifty-nine percent of fasciotomy wounds were closed by delayed primary closure, 26% had split-thickness skin grafts, and 15% had primary wound closure. Neurological deficits were the most common complications. There are limited data on thigh compartment syndrome with respect to cause, use of one versus two incisions for fasciotomy, methods of wound closure, and complication rates. Prospective studies are required to better define these variables in order to optimise the management of this problem. Copyright 2009 Elsevier Ltd. All rights reserved.

  8. Acute lumbar paraspinal compartment syndrome: a systematic review. (United States)

    Alexander, William; Low, Nelson; Pratt, George


    While still a rare entity, acute lumbar paraspinal compartment syndrome has an increasing incidence. Similar to other compartment syndromes, acute lumbar paraspinal compartment syndrome is defined by raised pressure within a closed fibro-osseous space, limiting tissue perfusion within that space. The resultant tissue ischaemia presents as acute pain, and if left untreated, it may result in permanent tissue damage. A literature search of 'paraspinal compartment syndrome' revealed 21 articles. The details from a case encountered by the authors are also included. A common data set was extracted, focusing on demographics, aetiology, clinical features, management and outcomes. There are 23 reported cases of acute compartment syndrome. These are typically caused by weight-lifting exercises, but may also result from other exercises, direct trauma or non-spinal surgery. Pain, tenderness and paraspinal paraesthesia are key clinical findings. Serum creatine kinase, magnetic resonance imaging and intracompartment pressure measurement confirm the diagnosis. Half of the reported cases have been managed with surgical fasciotomy, and these patients have all had good outcomes relative to those managed with conservative measures with or without hyperbaric oxygen therapy. These good outcomes were despite significant delays to operative intervention. The diagnostic uncertainty and subsequent delay to fasciotomy result from the rarity of this disease entity, and a high level of suspicion is recommended in the appropriate setting. This is particularly true in light of the current popularity of extreme weight lifting in non-professional athletes. Operative intervention is strongly recommended in all cases based on the available evidence. © 2018 Royal Australasian College of Surgeons.

  9. Lift-and-fill face lift: integrating the fat compartments. (United States)

    Rohrich, Rod J; Ghavami, Ashkan; Constantine, Fadi C; Unger, Jacob; Mojallal, Ali


    Recent discovery of the numerous fat compartments of the face has improved our ability to more precisely restore facial volume while rejuvenating it through differential superficial musculoaponeurotic system treatment. Incorporation of selective fat compartment volume restoration along with superficial musculoaponeurotic system manipulation allows for improved control in recontouring while addressing one of the key problems in facial aging, namely, volume deflation. This theory was evaluated by assessing the contour changes from simultaneous face "lifting" and "filling" through fat compartment-guided facial fat transfer. A review of 100 face-lift patients was performed. All patients had an individualized component face lift with fat grafting to the nasolabial fold, deep malar, and high/lateral malar fat compartment locations. Photographic analysis using a computer program was conducted on oblique facial views preoperatively and postoperatively, to obtain the most projected malar contour point. Two independent observers visually evaluated the malar prominence and nasolabial fold improvements based on standardized photographs. Nasolabial fold improved by at least one grade in 81 percent and by over one grade in 11 percent. Malar prominence average projection increase was 13.47 percent and the average amount of lift was 12.24 percent. The malar prominence score improved by at least one grade in 62 percent of the patients postoperatively, and 9 percent had a greater than one grade improvement. Twenty-eight percent of the patients had a convex malar prominence postoperatively compared with 6 percent preoperatively. Malar prominence improved by at least one grade in 63 percent and by over one grade in 10 percent. The lift-and-fill face lift merges two key concepts in facial rejuvenation: (1) effective tissue manipulation by means of lifting and tightening in differential vectors according to original facial asymmetry and shape; and (2) selective fat compartment filling

  10. Multimodal delivery of irinotecan from microparticles with two distinct compartments. (United States)

    Rahmani, Sahar; Park, Tae-Hong; Dishman, Acacia Frances; Lahann, Joerg


    In the last several decades, research in the field of drug delivery has been challenged with the fabrication of carrier systems engineered to deliver therapeutics to the target site with sustained and controlled release kinetics. Herein, we report the fabrication of microparticles composed of two distinct compartments: i) one compartment containing a pH responsive polymer, acetal-modified dextran, and PLGA (polylactide-co-glycolide), and ii) one compartment composed entirely of PLGA. We demonstrate the complete release of dextran from the microparticles during a 10-hour period in an acidic pH environment and the complete degradation of one compartment in less than 24h. This is in congruence with the stability of the same microparticles in neutral pH over the 24-hour period. Such microparticles can be used as pH responsive carrier systems for drug delivery applications where their cargo will only be released when the optimum pH window is reached. The feasibility of the microparticle system for such an application was confirmed by encapsulating a cancer therapeutic, irinotecan, in the compartment containing the acetal-modified dextran polymer and the pH dependent release over a 5-day period was studied. It was found that upon pH change to an acidic environment, over 50% of the drug was first released at a rapid rate for 10h, similar to that observed for the dextran release, before continuing at a more controlled rate for 4 days. As such, these microparticles can play an important role in the fabrication of novel drug delivery systems due to the selective, controlled, and pH responsive release of their encapsulated therapeutics. © 2013.

  11. Reactor Safety Planning for Prometheus Project, for Naval Reactors Information

    Energy Technology Data Exchange (ETDEWEB)

    P. Delmolino


    The purpose of this letter is to submit to Naval Reactors the initial plan for the Prometheus project Reactor Safety work. The Prometheus project is currently developing plans for cold physics experiments and reactor prototype tests. These tests and facilities may require safety analysis and siting support. In addition to the ground facilities, the flight reactor units will require unique analyses to evaluate the risk to the public from normal operations and credible accident conditions. This letter outlines major safety documents that will be submitted with estimated deliverable dates. Included in this planning is the reactor servicing documentation and shipping analysis that will be submitted to Naval Reactors.

  12. Scaleable, High Efficiency Microchannel Sabatier Reactor Project (United States)

    National Aeronautics and Space Administration — A Microchannel Sabatier Reactor System (MSRS) consisting of cross connected arrays of isothermal or graded temperature reactors is proposed. The reactor array...

  13. The Keelung Submarine Volcano in the near-shore area of northern Taiwan and its tectonic implication (United States)

    Tsai, Ching-Hui; Hsu, Shu-Kun; Lin, Shiao-Shan; Yang, Tsanyao F.; Wang, Shiou-Ya; Doo, Wen-Bin; Lee, Hsiao-Fen; Lan, Tefang; Huang, Jian-Cheng; Liang, Chin-Wei


    The Taiwan mountain belt has been created due to the collision between the Philippine Sea Plate and the Eurasian Plate. Northernmost Taiwan and its offshore area are now under post-collisional collapse. The post-collisional magmatism is distributed around northern Taiwan. Here we first report a submarine volcano, named Keelung Submarine Volcano, existing in the near-shore area of northern Taiwan. The high 3He/4He ratios in the collected seawater samples suggest that the magma of the Keelung Submarine Volcano is derived from a mantle source. Geometrically, both the Keelung Submarine Volcano and the Tatun Volcano Group are situated above the western border of the subducted Philippine Sea Plate and may have a same magma source. Both volcanic areas belong to the northern Taiwan volcanic zone, instead of the Ryukyu volcanic front. The Keelung Submarine Volcano has been rotated clockwise ∼48° after its formation, which implies that the Keelung Submarine Volcano has formed before the Luzon arc collided against northern Taiwan. Consequently, the post-collisional model to explain the formation of the northern Taiwan volcanic zone is questionable. As indicated by numerous shallow earthquakes and persistent emissions of the volcanic gases out of the seafloor around the volcanic cone, the Keelung Submarine Volcano is as active as the Tatun Volcano Group. For the sake of volcanic hazard assessment, it is essential to monitor the activity of the Keelung Submarine Volcano.

  14. CFD RANS Simulations on a Generic Conventional Scale Model Submarine: Comparison between Fluent and OpenFOAM (United States)


    1 – Hydrodynamics”, Defence Science and Technology Organisation Technical Report DSTO-TR-1622, 2004. UNCLASSIFIED DST-Group-TN-1449 UNCLASSIFIED...17 7. Joubert, P.N., “Some Aspects of Submarine Design Part 2– Shape of a Submarine 2026”, Defence Science and Technology Organisation Technical

  15. Parametric HECTR calculations of hydrogen transport and combustion at N Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Payne, A.C. Jr.; Camp, A.L.


    This report describes a limited number of parametric calculations of hydrogen transport and combustion in the N Reactor confinement for selected accident sequences. The calculations are performed using the HECTR computer code, which is a lumped-parameter code developed specifically for evaluating hydrogen behavior in reactor containments. A number of parameters are evaluated in this study, including hydrogen source rate, spray effects, and source location. The calculations indicate that mixing within major compartments tends to occur fairly rapidly, but that mixing between compartments can be inhibited in certain situations, resulting in the formation of flammable mixtures. These results are being compared to calculations performed with other computer codes, including a code that uses finite-difference models. United Nuclear Corporation will present the results of these code comparisons in future reports.

  16. Steam drum level control studies of a natural circulation multi loop reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rajesh; Contractor, A.D.; Srivastava, Abhishek; Lele, H.G. [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Reactor Safety Div.; Vaze, K.K. [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Reactor Design and Development Group


    The proposed heavy water moderated and light water cooled pressure tube type boiling water reactor works on natural circulation at all power levels. It has parallel inter-connected loops with 452 boiling channels in the main heat transport system configuration. These multiple (four) interconnected loops influence the steam drum level control adversely through the common reactor inlet header. Alternate design studies made earlier for efficient control of SD levels have shown favorable results. This has lead to explore further the present scheme with the compartmentalization of CRIH into four compartments catering to four loops separately. The conventional 3-element level control has been found to be working satisfactorily. The interconnections between ECCS header and inlet header compartments have also increased the safety margin for various LOCA and design basis events. The paper deals with the SD level control aspects for this novel MHT configuration which has been analyzed for various PIEs (Postulated Initiating Events) and found to be satisfactory. (orig.)

  17. High accuracy station moving method for total station in submarine construction

    Directory of Open Access Journals (Sweden)

    MIN Shaosong


    Full Text Available [Objectives] When we measure submarine pressure hulls using a total station, it is essential to set several stations in order to complete the measurement of the whole cabin due to the complicated measuring environment. However, there are many restrictions related to the total station itself when moving stations, and it is also difficult to ensure measuring accuracy and satisfy the requirements of submarine measurement in complicated environments.[Methods] As such, a new station moving method is presented which can automatically establish standing relationships by measuring common points at every measuring position.[Results] This method can significantly improve accuracy and efficiency.[Conclusions] The experiment shows that the results of the new station moving method can meet sub-pixel precision and satisfy submarine measurement requirements with high accuracy.

  18. Submarine landslide and tsunami hazards offshore southern Alaska: Seismic strengthening versus rapid sedimentation (United States)

    Sawyer, Derek E.; Reece, Robert S.; Gulick, Sean P. S.; Lenz, Brandi L.


    The southern Alaskan offshore margin is prone to submarine landslides and tsunami hazards due to seismically active plate boundaries and extreme sedimentation rates from glacially enhanced mountain erosion. We examine the submarine landslide potential with new shear strength measurements acquired by Integrated Ocean Drilling Program Expedition 341 on the continental slope and Surveyor Fan. These data reveal lower than expected sediment strength. Contrary to other active margins where seismic strengthening enhances slope stability, the high-sedimentation margin offshore southern Alaska behaves like a passive margin from a shear strength perspective. We interpret that seismic strengthening occurs but is offset by high sedimentation rates and overpressure. This conclusion is supported by shear strength outside of the fan that follow an active margin trend. More broadly, seismically active margins with wet-based glaciers are susceptible to submarine landslide hazards because of the combination of high sedimentation rates and earthquake shaking.

  19. The Zambezi Channel: A new perspective on submarine channel evolution at low latitudes (United States)

    Wiles, E.; Green, A.; Watkeys, M.; Jokat, W.


    Submarine channels are not stand-alone systems. They are long-lived systems modified by imperceptibly slow processes and rapid gravity flows, in some part controlled by hinterland dynamics. The submarine Zambezi Channel, within the Mozambique Channel, receives sediment from the Zambezi River catchment which has a dynamic tectonic and morphological history. Using recently collected multibeam bathymetry and PARASOUND data we discuss the geomorphology of the Zambezi Channel. Results show this system to be distinct in geomorphologic character when compared to other low-latitude submarine channels, sharing similarities with high-latitude systems. We propose a new, source-to-sink, hypothesis for the evolution of the Zambezi Channel, taking in to consideration hinterland tectonics, palaeo-lake development, river capture and rapid gravity flows. This hypothesis accounts for the unique present-day anatomy of the Zambezi Channel within the dynamic framework of the systems regional setting.

  20. Research on Big Data Attribute Selection Method in Submarine Optical Fiber Network Fault Diagnosis Database

    Directory of Open Access Journals (Sweden)

    Chen Ganlang


    Full Text Available At present, in the fault diagnosis database of submarine optical fiber network, the attribute selection of large data is completed by detecting the attributes of the data, the accuracy of large data attribute selection cannot be guaranteed. In this paper, a large data attribute selection method based on support vector machines (SVM for fault diagnosis database of submarine optical fiber network is proposed. Mining large data in the database of optical fiber network fault diagnosis, and calculate its attribute weight, attribute classification is completed according to attribute weight, so as to complete attribute selection of large data. Experimental results prove that ,the proposed method can improve the accuracy of large data attribute selection in fault diagnosis database of submarine optical fiber network, and has high use value.

  1. Chemical Fluxes from a Recently Erupted Submarine Volcano on the Mariana Arc (United States)

    Buck, N. J.; Resing, J. A.; Lupton, J. E.; Larson, B. I.; Walker, S. L.; Baker, E. T.


    While hydrothermal circulation is paramount to the geochemical budget for a wide array of elements, relatively few flux estimates exist in the literature. To date most studies have concentrated on constraining global and vent-field scale inputs originating from ocean spreading ridges. The goal of this study is to directly measure the chemical flux from an active submarine volcano injecting hydrothermal fluids into the surface ocean. Ahyi Seamount, a submarine intraoceanic arc volcano located in the Northern Mariana Islands, has a summit depth TSM and total and dissolved Fe and Mn. Laboratory analyses found enriched concentrations of H2, 3He, CO2 and Fe, consistent with a recent eruption. Preliminary flux calculations estimate a Fe input of 16 mmol s-1. This indicates shallow submarine arc volcanoes are capable of supplying appreciable quantities of Fe into the surface ocean. Further laboratory analyses and calculations to characterize and constrain the fluxes of other chemical constituents are underway.

  2. Origin of the Easter Submarine Alignment: morphology and structural lineaments

    Directory of Open Access Journals (Sweden)

    Cristián Rodrigo


    Full Text Available The Easter submarine alignment corresponds to a sequence of seamounts and oceanic islands which runs from the Ahu-Umu volcanic fields in the west to its intersection with the Nazca Ridge in the east, with a total length of about 2.900 km and a strike of N85°E. Recent bathymetric compilations that include combined satellite derived and shipboard data (Global Topography and multibeam bathymetric data (from NGDC-NOAA are interpreted both qualitatively and quantitatively by using a morphological analysis, which was comprised of the determination of bathymetric patterns, trends in lineations and structures; height measurements, computation of basal areas and volumes of seamounts, in order to establish clues on the origin of this seamount chain and to establish relationships with the regional tectonics. In the study region 514 seamounts were counted, of which 334 had a basal area less than the reference seamount (Moai. In general, the largest seamounts (>1000 m in height tend to align and to have a larger volume, with an elongation of their bases along the seamount chain. On the other hand, smaller seamounts tend to be distributed more randomly with more circular bases. As a consequence of the morphological analysis, the best possible mechanism that explains the origin of the seamount chain is the existence of a localized hotspot to the west of the Salas y Gómez Island. The corresponding plume would contribute additional magmatic material towards the East Pacific Rise through canalizations, whose secondary branches would feed intermediate volcanoes. It is possible that within the Easter Island region there would be another minor contribution through fractures in the crust, due to the crustal weakening that was produced by the Easter Fracture Zone.

  3. The Atlas of Submarine Glacial Landforms: Modern, Quaternary and Ancient (United States)

    Dowdeswell, Julian A.; Canals, Miquel; Jakobsson, Martin; Todd, Brian J.; Dowdeswell, Evelyn K.; Hogan, Kelly A.


    Twenty years ago, the international marine community brought together a first Atlas of Acoustic Images of the high-latitude geo-marine environment (Davies et al. 1997). The present Atlas is a new attempt to summarize the state of knowledge of high-latitude glacier-influenced systems, focusing on HR imagery derived from multibeam swath bathymetry and novel 2D and 3D seismic reflection tools. These new-generation techniques, aided by accurate global positioning, have revolutionized the imaging of the seafloor and subseafloor over the past two decades and have now been deployed widely in polar and subpolar waters, providing vast quantities of new data. It is, therefore, timely to provide a compilation of the variety of submarine glacial and related landforms, together with their stratigraphic setting where possible, for scientific, technological, environmental and economic reasons. The glacial imprint on the modern seabed and palaeo-shelf surfaces, buried in glacial-sedimentary depocentres, can now be imaged better than ever before using the above techniques, providing novel insights into present and past environmental conditions and sedimentary architecture. The understanding of polar regions and their changing ice cover is of enhanced significance as they are both a key driver of global change and important responders to it. Finally, industry is increasingly interested on the dimensions and architecture of glacial sedimentary depocentres on present and past continental shelves because of the hydrocarbon potential of some glacial-sedimentary systems. The Atlas consists of a comprehensive series of over 180 contributions that describe, illustrate and discuss the full variability of landforms found on the high-latitude, glacier-influenced systems, and is organised in terms of their positions on a continental margin into those from: (1) fjords, (2) continental shelves and plateaus, and (3) the deep margin and basins beyond. The Atlas has been published by the Geological

  4. Seismic site response of submarine slope offshore southwestern Taiwan

    Directory of Open Access Journals (Sweden)

    Jing-Yi Lin


    Full Text Available Widely distributed Bottom-Simulating Reflectors (BSRs have been observed in the area offshore of southwestern Taiwan where the active accretionary complex meets with the passive China continental margin. In order to clarify the link between seismic site response and sedimentary properties of submarine slope, we evaluate the response of seafloor sediments in regard to passive dynamic loads. The local site effect produced by shallow marine sediments was characterized by estimating the horizontal-to-vertical (H/V spectral ratios of data recorded by the short-period Ocean Bottom Seismometers (OBSs. The results show that the maximal H/V ratios appeared in the range of 3.66 - 9.28 Hz, suggesting that the fundamental frequency is dominated by the effect related to the very shallow sediments. For most stations, the H/V ratios estimated based on the earthquakes and noise records were characterized by different patterns. Relatively broad H/V pattern was obtained when the signals were extracted from earthquakes. This phenomenon may be related to soil nonlinearity when a stronger motion applies. In comparison with the available geological structures and bulk density distribution obtained from coring experiments, we found a relatively higher fundamental frequency of about 8 - 9 Hz for the more rigid material, such as mud diapir and folding axes. For most of the area along the slope, the fundamental frequency shows a relatively low value, about 6 - 8 Hz. Finally, when a site is characterized by thick or lowest bulk density sedimentary layer, we observed a fundamental frequency lower than 5 Hz, which is the lowest in our assessment.

  5. Potential Impact of Submarine Power Cables on Crab Harvest (United States)

    Bull, A. S.; Nishimoto, M.


    Offshore renewable energy installations convert wave or wind energy to electricity and transfer the power to shore through transmission cables laid on or buried beneath the seafloor. West coast commercial fishermen, who harvest the highly prized Dungeness crab (Metacarcinus magister) and the rock crab (Cancer spp.), are concerned that the interface of crabs and electromagnetic fields (EMF) from these cables will present an electrified fence on the seafloor that their target resource will not cross. Combined with the assistance of professional fishermen, submarine transmission cables that electrify island communities and offshore oil platforms in the eastern Pacific provide an opportunity to test the harvest of crab species across power transmission cables. In situ field techniques give commercial crab species a choice to decide if they will cross fully energized, EMF emitting, power transmission cables, in response to baited traps. Each independent trial is either one of two possible responses: the crab crosses the cable to enter a trap (1) or the crab does not cross the cable to enter a trap (0). Conditions vary among sample units by the following categorical, fixed factors (i.e., covariates) of cable structure (buried or unburied); direction of cable from crab position (west or east, north or south); time and season. A generalized linear model is fit to the data to determine whether any of these factors affect the probability of crabs crossing an energized cable to enter baited traps. Additionally, the experimental design, aside from the number of runs (set of sample trials) and the dates of the runs, is the same in the Santa Barbara Channel for rock crab and Puget Sound for Dungeness crab, and allows us to compare the capture rates of the two species in the two areas. We present preliminary results from field testing in 2015.

  6. Anatomy of La Jolla submarine canyon system; offshore southern California (United States)

    Paull, C.K.; Caress, D.W.; Lundsten, E.; Gwiazda, R.; Anderson, K.; McGann, M.; Conrad, J.; Edwards, B.; Sumner, E.J.


    An autonomous underwater vehicle (AUV) carrying a multibeam sonar and a chirp profiler was used to map sections of the seafloor within the La Jolla Canyon, offshore southern California, at sub-meter scales. Close-up observations and sampling were conducted during remotely operated vehicle (ROV) dives. Minisparker seismic-reflection profiles from a surface ship help to define the overall geometry of the La Jolla Canyon especially with respect to the pre-canyon host sediments. The floor of the axial channel is covered with unconsolidated sand similar to the sand on the shelf near the canyon head, lacks outcrops of the pre-canyon host strata, has an almost constant slope of 1.0° and is covered with trains of crescent shaped bedforms. The presence of modern plant material entombed within these sands confirms that the axial channel is presently active. The sand on the canyon floor liquefied during vibracore collection and flowed downslope, illustrating that the sediment filling the channel can easily fail even on this gentle slope. Data from the canyon walls help constrain the age of the canyon and extent of incision. Horizontal beds of moderately cohesive fine-grained sediments exposed on the steep canyon walls are consistently less than 1.232 million years old. The lateral continuity of seismic reflectors in minisparker profiles indicate that pre-canyon host strata extend uninterrupted from outside the canyon underneath some terraces within the canyon. Evidence of abandoned channels and point bar-like deposits are noticeably absent on the inside bend of channel meanders and in the subsurface of the terraces. While vibracores from the surface of terraces contain thin (< 10 cm) turbidites, they are inferred to be part of a veneer of recent sediment covering pre-canyon host sediments that underpin the terraces. The combined use of state of the art seafloor mapping and exploration tools provides a uniquely detailed view of the morphology within an active submarine canyon.

  7. Scattering effect of submarine hull on propeller non-cavitation noise (United States)

    Wei, Yingsan; Shen, Yang; Jin, Shuanbao; Hu, Pengfei; Lan, Rensheng; Zhuang, Shuangjiang; Liu, Dezhi


    This paper investigates the non-cavitation noise caused by propeller running in the wake of submarine with the consideration of scattering effect caused by submarine's hull. The computation fluid dynamics (CFD) and acoustic analogy method are adopted to predict fluctuating pressure of propeller's blade and its underwater noise radiation in time domain, respectively. An effective iteration method which is derived in the time domain from the Helmholtz integral equation is used to solve multi-frequency waves scattering due to obstacles. Moreover, to minimize time interpolation caused numerical errors, the pressure and its derivative at the sound emission time is obtained by summation of Fourier series. It is noted that the time averaging algorithm is used to achieve a convergent result if the solution oscillated in the iteration process. Meanwhile, the developed iteration method is verified and applied to predict propeller noise scattered from submarine's hull. In accordance with analysis results, it is summarized that (1) the scattering effect of hull on pressure distribution pattern especially at the frequency higher than blade passing frequency (BPF) is proved according to the contour maps of sound pressure distribution of submarine's hull and typical detecting planes. (2) The scattering effect of the hull on the total pressure is observable in noise frequency spectrum of field points, where the maximum increment is up to 3 dB at BPF, 12.5 dB at 2BPF and 20.2 dB at 3BPF. (3) The pressure scattered from hull is negligible in near-field of propeller, since the scattering effect surrounding analyzed location of propeller on submarine's stern is significantly different from the surface ship. This work shows the importance of submarine's scattering effect in evaluating the propeller non-cavitation noise.

  8. Simple models for the simulation of submarine melt for a Greenland glacial system model (United States)

    Beckmann, Johanna; Perrette, Mahé; Ganopolski, Andrey


    Two hundred marine-terminating Greenland outlet glaciers deliver more than half of the annually accumulated ice into the ocean and have played an important role in the Greenland ice sheet mass loss observed since the mid-1990s. Submarine melt may play a crucial role in the mass balance and position of the grounding line of these outlet glaciers. As the ocean warms, it is expected that submarine melt will increase, potentially driving outlet glaciers retreat and contributing to sea level rise. Projections of the future contribution of outlet glaciers to sea level rise are hampered by the necessity to use models with extremely high resolution of the order of a few hundred meters. That requirement in not only demanded when modeling outlet glaciers as a stand alone model but also when coupling them with high-resolution 3-D ocean models. In addition, fjord bathymetry data are mostly missing or inaccurate (errors of several hundreds of meters), which questions the benefit of using computationally expensive 3-D models for future predictions. Here we propose an alternative approach built on the use of a computationally efficient simple model of submarine melt based on turbulent plume theory. We show that such a simple model is in reasonable agreement with several available modeling studies. We performed a suite of experiments to analyze sensitivity of these simple models to model parameters and climate characteristics. We found that the computationally cheap plume model demonstrates qualitatively similar behavior as 3-D general circulation models. To match results of the 3-D models in a quantitative manner, a scaling factor of the order of 1 is needed for the plume models. We applied this approach to model submarine melt for six representative Greenland glaciers and found that the application of a line plume can produce submarine melt compatible with observational data. Our results show that the line plume model is more appropriate than the cone plume model for simulating

  9. Submarine geology and geomorphology of active Sub-Antarctic volcanoes: Heard and McDonald Islands (United States)

    Watson, S. J.; Coffin, M. F.; Whittaker, J. M.; Lucieer, V.; Fox, J. M.; Carey, R.; Arculus, R. J.; Bowie, A. R.; Chase, Z.; Robertson, R.; Martin, T.; Cooke, F.


    Heard and McDonald Islands (HIMI) are World Heritage listed sub-Antarctic active volcanic islands in the Southern Indian Ocean. Built atop the Kerguelen Plateau by Neogene-Quaternary volcanism, HIMI represent subaerial exposures of the second largest submarine Large Igneous Province globally. Onshore, processes influencing island evolution include glaciers, weathering, volcanism, vertical tectonics and mass-wasting (Duncan et al. 2016). Waters surrounding HIMI are largely uncharted, due to their remote location. Hence, the extent to which these same processes shape the submarine environment around HIMI has not been investigated. In early 2016, we conducted marine geophysical and geologic surveys around HIMI aboard RV Investigator (IN2016_V01). Results show that volcanic and sedimentary features prominently trend east-west, likely a result of erosion by the eastward flowing Antarctic Circumpolar Current and tidal currents. However, spatial patterns of submarine volcanism and sediment distribution differ substantially between the islands. >70 sea knolls surround McDonald Island suggesting substantial submarine volcanism. Geophysical data reveals hard volcanic seafloor around McDonald Island, whereas Heard Island is characterised by sedimentary sequences tens of meters or more thick and iceberg scours - indicative of glacial processes. Differences in submarine geomorphology are likely due to the active glaciation of Heard Island and differing rock types (Heard: alkali basalt, McDonald: phonolite), and dominant products (clastics vs. lava). Variations may also reflect different magmatic plumbing systems beneath the two active volcanoes (Heard produces larger volumes of more focused lava, whilst McDonald extrudes smaller volumes of more evolved lavas from multiple vents across the edifice). Using geophysical data, corroborated with new and existing geologic data, we present the first geomorphic map revealing the processes that shape the submarine environment around HIMI.


    Mumm, J.F.; North, D.C. Jr.; Rock, H.R.; Geston, D.K.


    A nuclear reactor is described for use in a merchant marine ship. The reactor is of pressurized light water cooled and moderated design in which three passes of the water through the core in successive regions of low, intermediate, and high heat generation and downflow in a fuel region are made. The foregoing design makes a compact reactor construction with extended core life. The core has an egg-crate lattice containing the fuel elements confined between a lower flow baffle and upper grid plate, with the latter serving also as part of a turn- around manifold from which the entire coolant is distributed into the outer fuel elements for the second pass through the core. The inner fuel elements are cooled in the third pass.

  11. Nuclear Rocket Engine Reactor

    CERN Document Server

    Lanin, Anatoly


    The development of a nuclear rocket engine reactor (NRER ) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  12. Nuclear reactor safety device (United States)

    Hutter, Ernest


    A safety device is disclosed for use in a nuclear reactor for axially repositioning a control rod with respect to the reactor core in the event of an upward thermal excursion. Such safety device comprises a laminated helical ribbon configured as a tube-like helical coil having contiguous helical turns with slidably abutting edges. The helical coil is disclosed as a portion of a drive member connected axially to the control rod. The laminated ribbon is formed of outer and inner laminae. The material of the outer lamina has a greater thermal coefficient of expansion than the material of the inner lamina. In the event of an upward thermal excursion, the laminated helical coil curls inwardly to a smaller diameter. Such inward curling causes the total length of the helical coil to increase by a substantial increment, so that the control rod is axially repositioned by a corresponding amount to reduce the power output of the reactor.

  13. Heat dissipating nuclear reactor (United States)

    Hunsbedt, A.; Lazarus, J.D.


    Disclosed is a nuclear reactor containment adapted to retain and cool core debris in the unlikely event of a core meltdown and subsequent breach in the reactor vessel. The reactor vessel is seated in a cavity which has a thick metal sidewall that is integral with a thick metal basemat at the bottom of the cavity. The basemat extends beyond the perimeter of the cavity sidewall. Underneath the basemat is a porous bed with water pipes and steam pipes running into it. Water is introduced into the bed and converted into steam which is vented to the atmosphere. A plurality of metal pilings in the form of H-beams extend from the metal base plate downwardly and outwardly into the earth.

  14. Reactor for exothermic reactions (United States)

    Smith, Jr., Lawrence A.; Hearn, Dennis; Jones, Jr., Edward M.


    A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of to F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  15. Impact of Submarine Geohazards on Organic Carbon Burial Offshore Southwestern Taiwan (United States)

    Su, C. C.; Tsai, P. H.; Liu, J. T.; Hsu, S. K.; Chiu, S. D.


    The tectonically active setting and climatic conditions give Taiwan a high exposure to severe natural hazards. After the Pingtung Earthquake and Morakot Typhoon which occurred in 2006 and 2009, the turbidity currents caused a series of submarine cable breaks along the Gaoping and Fangliao Submarine Canyons off SW Taiwan. Large amounts of terrestrial sediments were fast transported bypass the narrow continental shelf and rapidly moved southward through submarine canyons to the deep sea. Two piston cores which were taken from the Tsangyao Ridge and its adjacent area (OR5-1302-2-MT7 and MT6) might shed light on understanding the export of terrestrial organic carbon to the abyss by submarine geo-hazards. The 210Pb profile of MT7 in conjunction with the grain size data indicates the existence of the Pingtung Earthquake and Morakot Typhoon related deposits. The sedimentation rate of these two cores which derived from 210Pb is approximately 0.05 cm/yr. The cores collected from the Gaoping Submarine Canyon, Gaoping Slope and Fangliao Submarine Canyon are used for analyzing TOC, organic C/N and δ13C ratios. The concentrations of total organic carbon are ~0.5%, and C/N rations almost remain between 4 and 8. The high TOC (~1%) and C/N ratio (>10) are observed in the samples with plant debris. The fluctuation of TOC and C/N ratios in near-shore samples is higher than deep sea. In terms of δ13C-values, it progressively decreases with distances from coastal zone to the deep sea. Due to the larger proportions of land-derived organic carbon, the δ13C-values in the surface sediment of upper Gaoping Submarine Canyon, Gaoping Slope, and the turbidite layers at the head of Fangliao Submarine Canyon are lighter. Furthermore, we use the TOC concentrations and δ13C-values to estimate the fractional contributions of terrestrial organic carbon by a simple two component mixing model, and integrate with the 210Pb-derived sediment accumulation rates to evaluate the organic carbon burial

  16. Modeling and Synthesis Methods for Retrofit Design of Submarine Actuation Systems. Energy Storage for Electric Actuators (United States)


    sternplane v - sway w - heave u - surge X Y Z y z x Figure 2: Coordinate frame definitions of submarine vehicular dynamics. 2.1 Six Degree of Freedom...where Mν̇ is the total inertial matrix, C(ν) is the Coriolis/centripetal matrix, D(ν) is the total damping matrix, g(η) are the buoyancy and weight...Natick, MA. Retrofit Design of Submarine Actuation Systems Page 7 q - pitch w - heave u - surge δs Msp Figure 3: Hydrodynamic moment unit definition

  17. The impact of the Type 094 ballistic missile submarine on China's nuclear policy


    Bell, Samuel D.


    Approved for public release, distribution unlimited This thesis examines the implication of China’s near completion of a viable nuclear triad. The objective is to determine first, how this submarine will fit into China’s no-first-use policy with regards to their nuclear weapons. And second, determine how advanced this weapon platform will be. With the introduction of multiple Type 094 “Jin” class ballistic missile submarines, has Beijing set the stage for a possible return to Cold War leve...

  18. Oceanographic studies supporting the assessment of deep-sea disposal of defueled decommissioned nuclear submarines (United States)

    Ross Heath, G.; Rea, David K.; Ness, Gordon; Dale Pillsbury, R.; Beasley, Thomas M.; Lopez, Carlos; Talbert, Daniel M.


    Based on criteria developed by the international Atomic Energy Agency (IAEA), potential disposal sites for defueled, decommissioned nuclear submarines appear to exist in deep water south of the Mendocino Fracture Zone within 200 nautical miles of the United States Oceanographic measurements in the water column and at the sea floor in a study area (W-N) at 39 5°N, 127 5°W will allow the operational and radiological consequences of deep-sea disposal to be compared with land burial of old submarines. The W-N studies also are yielding new data that will provide insights to the deposition and early diagenesis of distal hemipelagic sediments

  19. An Overview of Reactor Concepts, a Survey of Reactor Designs. (United States)


    implies, this reactor uses gas as the primary coolant . The coolant has a higher exit temperature when leaving the core than the PWR water 6 AFWL-TN-84...nuclear reactors, coolants must be used to ensure material components are not subject to failure due to the temperature exceeding melting points...Reactors that use deu- terium (heavy water) as a coolant can use natural uranium as a fuel. The * Canadian reactor, CANDU , utilizes this concept

  20. Oscillatory flow chemical reactors

    Directory of Open Access Journals (Sweden)

    Slavnić Danijela S.


    Full Text Available Global market competition, increase in energy and other production costs, demands for high quality products and reduction of waste are forcing pharmaceutical, fine chemicals and biochemical industries, to search for radical solutions. One of the most effective ways to improve the overall production (cost reduction and better control of reactions is a transition from batch to continuous processes. However, the reactions of interests for the mentioned industry sectors are often slow, thus continuous tubular reactors would be impractically long for flow regimes which provide sufficient heat and mass transfer and narrow residence time distribution. The oscillatory flow reactors (OFR are newer type of tube reactors which can offer solution by providing continuous operation with approximately plug flow pattern, low shear stress rates and enhanced mass and heat transfer. These benefits are the result of very good mixing in OFR achieved by vortex generation. OFR consists of cylindrical tube containing equally spaced orifice baffles. Fluid oscillations are superimposed on a net (laminar flow. Eddies are generated when oscillating fluid collides with baffles and passes through orifices. Generation and propagation of vortices create uniform mixing in each reactor cavity (between baffles, providing an overall flow pattern which is close to plug flow. Oscillations can be created by direct action of a piston or a diaphragm on fluid (or alternatively on baffles. This article provides an overview of oscillatory flow reactor technology, its operating principles and basic design and scale - up characteristics. Further, the article reviews the key research findings in heat and mass transfer, shear stress, residence time distribution in OFR, presenting their advantages over the conventional reactors. Finally, relevant process intensification examples from pharmaceutical, polymer and biofuels industries are presented.

  1. Submarine landslide triggered by eruption recorded by in-situ hydrophone at NW Rota-1 submarine volcano, Mariana Arc (Invited) (United States)

    Chadwick, B.; Dziak, R. P.; Embley, R. W.; Tunnicliffe, V.; Sherrin, J.; Cashman, K. V.; Deardorff, N.


    An expedition to NW Rota-1, Mariana Arc, in March 2010 with R/V Kilo Moana and ROV Jason found that the submarine volcano (summit depth 520 m) was still erupting more or less continuously as has been observed since 2004, In addition, the expedition also discovered that a major landslide had occurred since the last visit in April 2009, demonstrating the dynamic processes of eruption, collapse, and regrowth in the submarine arc environment. The dive observations reveal the responses of the volcano’s magmatic and hydrothermal systems to such a collapse, as well as how the resident chemosynthetic biological community has responded to the event. The morphologic changes from the landslide can be quantified by comparing multibeam bathymetric surveys between 2009 and 2010. The headwall of the slide is now ~100 m north of the former summit ridge where depth changes up to -90 m occurred between surveys. The slide excavated material from the upper southern slope of the volcano to a distance of 3.5 km downslope, and deposited material between 2-8 km from the summit down to at least 2800 m on the volcano flank. The area and volume of slide deposits (positive depth changes) are 7.1 x 106 m2 and 5.3 x 107 m3, respectively, and the maximum thickness is +42 m. The area and volume of material removed by the slide (negative depth changes) are 2.2 x 106 m2 and -4.1 x 107 m3, respectively. We have found no evidence for a local tsunami generated by this event. The changes in morphology near the summit show that the landslide primarily removed loose volcaniclastic deposits that had accumulated near the active eruptive vent, exposing an underlying stock-like core of resistant intrusive rocks and massive lavas at the summit. During March 2010, there were at least 5 active eruptive vents, located along a line 200-m long, that changed between active and inactive day-to-day and even hour-to-hour, suggesting that the near-surface magmatic plumbing system was still reorganizing after the

  2. Atmospheric transport of radioactive debris to Norway in case of a hypothetical accident related to the recovery of the Russian submarine K-27. (United States)

    Bartnicki, Jerzy; Amundsen, Ingar; Brown, Justin; Hosseini, Ali; Hov, Øystein; Haakenstad, Hilde; Klein, Heiko; Lind, Ole Christian; Salbu, Brit; Szacinski Wendel, Cato C; Ytre-Eide, Martin Album


    The Russian nuclear submarine K-27 suffered a loss of coolant accident in 1968 and with nuclear fuel in both reactors it was scuttled in 1981 in the outer part of Stepovogo Bay located on the eastern coast of Novaya Zemlya. The inventory of spent nuclear fuel on board the submarine is of concern because it represents a potential source of radioactive contamination of the Kara Sea and a criticality accident with potential for long-range atmospheric transport of radioactive particles cannot be ruled out. To address these concerns and to provide a better basis for evaluating possible radiological impacts of potential releases in case a salvage operation is initiated, we assessed the atmospheric transport of radionuclides and deposition in Norway from a hypothetical criticality accident on board the K-27. To achieve this, a long term (33 years) meteorological database has been prepared and used for selection of the worst case meteorological scenarios for each of three selected locations of the potential accident. Next, the dispersion model SNAP was run with the source term for the worst-case accident scenario and selected meteorological scenarios. The results showed predictions to be very sensitive to the estimation of the source term for the worst-case accident and especially to the sizes and densities of released radioactive particles. The results indicated that a large area of Norway could be affected, but that the deposition in Northern Norway would be considerably higher than in other areas of the country. The simulations showed that deposition from the worst-case scenario of a hypothetical K-27 accident would be at least two orders of magnitude lower than the deposition observed in Norway following the Chernobyl accident. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E


    The activities of SCK-CEN's Reactor Materials Research Department for 2001 are summarised. The objectives of the department are: (1) to evaluate the integrity and behaviour of structural materials used in nuclear power industry; (2) to conduct research to unravel and understand the parameters that determine the material behaviour under or after irradiation; (3) to contribute to the interpretation, the modelling of the material behaviour and to develop and assess strategies for optimum life management of nuclear power plant components. The programmes within the department are focussed on studies concerning (1) Irradiation Assisted Stress Corrosion Cracking (IASCC); (2) nuclear fuel; and (3) Reactor Pressure Vessel Steel.

  4. Nuclear reactor apparatus (United States)

    Wade, Elman E.


    A lifting, rotating and sealing apparatus for nuclear reactors utilizing rotating plugs above the nuclear reactor core. This apparatus permits rotation of the plugs to provide under the plug refueling of a nuclear core. It also provides a means by which positive top core holddown can be utilized. Both of these operations are accomplished by means of the apparatus lifting the top core holddown structure off the nuclear core while stationary, and maintaining this structure in its elevated position during plug rotation. During both of these operations, the interface between the rotating member and its supporting member is sealingly maintained.

  5. Perspectives on reactor safety

    Energy Technology Data Exchange (ETDEWEB)

    Haskin, F.E. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering; Camp, A.L. [Sandia National Labs., Albuquerque, NM (United States)


    The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident progression in the reactor vessel; (4) containment characteristics and design bases; and (5) source terms and offsite consequences. The course text is accompanied by slides and videos during the actual presentation of the course.

  6. Safe reactor power

    Energy Technology Data Exchange (ETDEWEB)

    Menegus, R.L.; Ring, H.F.; Bernath, L.


    The upper limit on reactor operating power is established not only by safety considerations during steady-state operation but also by the requirement that during an accident no permanent damage be inflicted upon the reactor or the fuel charge. Two general categories of accidents are recognized; they are the ``nuclear runaway`` and the ``loss of coolant flow`` incidents. In this memorandum an incident of the latter type is analyzed. It is assumed that the safety rods function normally, and a method is defined for establishing the highest operating power that may be permitted if the postulated accident is to do no damage.

  7. Endoscopic Thermal Fasciotomy for Chronic Exertional Compartment Syndrome. (United States)

    Voleti, Pramod B; Lebrun, Drake G; Roth, Cameron A; Kelly, John D


    Chronic exertional compartment syndrome is an activity-induced condition that occurs when intracompartmental pressures within an osteofascial envelope increase during exercise, leading to reversible ischemic symptoms such as pain, cramping, numbness, or weakness. Nonoperative treatment options for this condition have shown limited success and are often undesirable for the patient given the requirement for activity modification. Traditional surgical treatment options involving open or subcutaneous fasciotomies have more favorable results, but these techniques are associated with significant morbidity. Endoscopically assisted fasciotomy techniques afford the advantages of being minimally invasive, providing excellent visualization, and allowing accelerated rehabilitation. The purpose of this article is to describe a technique for performing endoscopically assisted fasciotomies for chronic exertional compartment syndrome of the lower leg using an entirely endoscopic thermal ablating device. The endoscopic thermal fasciotomy technique is associated with minimal morbidity, ensures excellent hemostasis, and affords an early return to sports.

  8. Exercise-Induced Acute Bilateral Upper-Arm Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Brian C. Traub


    Full Text Available We present a rare case of acute exercise-induced bilateral upper-arm compartment syndrome in a patient who, after a year-long hiatus from exercise, subjected his upper-extremities to the stress of over 100 pushups. The patient presented with severe pain of the bilateral biceps and triceps and complaints of dark urine. Decompressive fasciotomy was performed followed by an intensive care unit (ICU stay for associated myoglobinuria secondary to rhabdomyolysis. The patient suffered no long-term sequelae as a result of his conditions and recovered full function of the bilateral upper-extremities. Albeit rare, acute exercise-induced compartment syndrome should be considered as a diagnosis following unaccustomed bouts of exercise.

  9. A New Etiology for the Abdominal Compartment Syndrome: Pseudomyxoma Peritonei

    Directory of Open Access Journals (Sweden)

    Charles Sabbagh


    Full Text Available Pseudomyxoma peritonei (PMP is a rare diagnosis with an incidence of 1-2 per million. Most cases originate from an appendix which ruptures and releases mucin into the peritoneal cavity. The progression of the disease results in obstruction and cutaneous leak. Abdominal compartment syndrome is an uncommon complication of peritoneal pseudomyxoma. In the present article, we report the case of a patient with PMP and abdominal compartment syndrome. A laparotomy to decrease the abdominal pressure was performed. Three months later, a peritonectomy with hyperthermic intraperitoneal chemotherapy was performed. The patient was still alive 1 year after the procedure without any recurrence. In conclusion, acute abdominal pain and respiratory failure in patients with peritoneal PMP should lead to the measurement of the abdominal pressure but are not a contra indication for curative treatment of PMP.

  10. Endoscopic Thermal Fasciotomy for Chronic Exertional Compartment Syndrome (United States)

    Voleti, Pramod B.; Lebrun, Drake G.; Roth, Cameron A.; Kelly, John D.


    Chronic exertional compartment syndrome is an activity-induced condition that occurs when intracompartmental pressures within an osteofascial envelope increase during exercise, leading to reversible ischemic symptoms such as pain, cramping, numbness, or weakness. Nonoperative treatment options for this condition have shown limited success and are often undesirable for the patient given the requirement for activity modification. Traditional surgical treatment options involving open or subcutaneous fasciotomies have more favorable results, but these techniques are associated with significant morbidity. Endoscopically assisted fasciotomy techniques afford the advantages of being minimally invasive, providing excellent visualization, and allowing accelerated rehabilitation. The purpose of this article is to describe a technique for performing endoscopically assisted fasciotomies for chronic exertional compartment syndrome of the lower leg using an entirely endoscopic thermal ablating device. The endoscopic thermal fasciotomy technique is associated with minimal morbidity, ensures excellent hemostasis, and affords an early return to sports. PMID:26900549

  11. Coexisting liquid phases underlie nucleolar sub-compartments (United States)

    Feric, Marina; Vaidya, Nilesh; Harmon, Tyler S.; Mitrea, Diana M.; Zhu, Lian; Richardson, Tiffany M.; Kriwacki, Richard W.; Pappu, Rohit V.; Brangwynne, Clifford P.


    Summary The nucleolus and other ribonucleoprotein (RNP) bodies are membrane-less organelles that appear to assemble through phase separation of their molecular components. However, many such RNP bodies contain internal sub-compartments, and the mechanism of their formation remains unclear. Here, we combine in vivo and in vitro studies, together with computational modeling, to show that sub-compartments within the nucleolus represent distinct, coexisting liquid phases. Consistent with their in vivo immiscibility, purified nucleolar proteins phase separate into droplets containing distinct non-coalescing phases that are remarkably similar to nucleoli in vivo. This layered droplet organization is caused by differences in the biophysical properties of the phases – particularly droplet surface tension – which arises from sequence-encoded features of their macromolecular components. These results suggest that phase separation can give rise to multilayered liquids that may facilitate sequential RNA processing reactions in a variety of RNP bodies. PMID:27212236

  12. Low-temperature anaerobic digestion of swine manure in a plug-flow reactor. (United States)

    Massé, Daniel I; Gilbert, Yan; Saady, N M C; Liu, Charle


    A low-temperature (25 degrees C) anaerobic eight-compartment (PF01 to PF08) cascade reactor simulating a plug-flow reactor (PFR) treating pig manure was monitored for a year. The bioreactor was fed at an average loading rate of 2.4 +/- 0.2 g of total chemical oxygen demand (TCOD) per litre of reactor per day for a theoretical hydraulic retention time (HRT) of 67 +/- 7 d. An average of 79% of TCOD was removed from pig manure (converted into biogas and in sediments), whereas specific methane yields ranging from 397 to 482 NL CH4 kg(-1) VS (148.6 to 171.4 NL CH4 kg(-1) TCOD) were obtained. After 150 d, fluctuating performances of the process were observed, associated with solids accumulation in the upstream compartments, preventing the complete anaerobic digestion of swine manure in the compartments PF01 to PF04. Low-temperature anaerobic PFR represents an interesting alternative for the treatment of pig manure and recovery of green energy. Further investigations regarding a modified design, with better accumulating solids management, are needed to optimize the performance of this low-temperature PFR treating pig manure.

  13. Endocytosis of desmosomal plaques depends on intact actin filaments and leads to a nondegradative compartment

    DEFF Research Database (Denmark)

    Holm, Pernille K.; Hansen, Steen H.; Sandvig, Kirsten


    Cellebiologi, human epithelial cell line, growth inhibition, desmosomes, clathrin-independent endocytosis, cytoskeleton, nondegradative compartment......Cellebiologi, human epithelial cell line, growth inhibition, desmosomes, clathrin-independent endocytosis, cytoskeleton, nondegradative compartment...

  14. Endoscopic Thermal Fasciotomy for Chronic Exertional Compartment Syndrome


    Voleti, Pramod B.; Lebrun, Drake G.; Roth, Cameron A.; Kelly, John D.


    Chronic exertional compartment syndrome is an activity-induced condition that occurs when intracompartmental pressures within an osteofascial envelope increase during exercise, leading to reversible ischemic symptoms such as pain, cramping, numbness, or weakness. Nonoperative treatment options for this condition have shown limited success and are often undesirable for the patient given the requirement for activity modification. Traditional surgical treatment options involving open or subcutan...

  15. Predicting Acute Compartment Syndrome (PACS): The Role of Continuous Monitoring. (United States)

    Schmidt, Andrew H; Bosse, Michael J; Frey, Katherine P; OʼToole, Robert V; Stinner, Daniel J; Scharfstein, Daniel O; Zipunnikov, Vadim; MacKenzie, Ellen J


    The diagnosis of acute compartment syndrome (ACS) is a common clinical challenge among patients who sustain high-energy orthopaedic trauma, largely because no validated criteria exist to reliably define the presence of the condition. In the absence of validated diagnostic standards, concern for the potential clinical and medicolegal impact of a missed compartment syndrome may result in the potential overuse of fasciotomy in "at-risk" patients. The goal of the Predicting Acute Compartment Syndrome Study was to develop a decision rule for predicting the likelihood of ACS that would reduce unnecessary fasciotomies while guarding against potentially missed ACS. Of particular interest was the utility of early and continuous monitoring of intramuscular pressure and muscle oxygenation using near-infrared spectroscopy in the timely diagnosis of ACS. In this observational study, 191 participants aged 18-60 with high-energy tibia fractures were prospectively enrolled and monitored for up to 72 hours after admission, then followed for 6 months. Treating physicians were blinded to continuous pressure and oxygenation data. An expert panel of 9 orthopaedic surgeons retrospectively assessed the likelihood that each patient developed ACS based on data collected on initial presentation, clinical course, and known functional outcome at 6 months. This retrospectively assigned likelihood is modeled as a function of clinical data typically available within 72 hours of admission together with continuous pressure and oxygenation data. This study will improve our understanding of the natural history of compartment syndrome and examine the utility of early and continuous monitoring of the physiologic status of the injured extremity in the timely diagnosis of ACS.

  16. Compartment Syndrome Following Directly Repair of Hernia of Anterior Tibialis

    Directory of Open Access Journals (Sweden)

    Yuan-Ta Li


    Full Text Available We present a case of a patient with hernia of anterior tibialis who was treated operatively. Muscle herniation through a fascial defect is rare, which requires repair of fascial defects. We performed a simple closure of fascial defect. A fasciotomy was proceeded to complication of acute compartment syndrome developed after the operation. The sequelae as weakness of dorsiflexion of ankle and big toe were present.

  17. Elimination behavior of shelter dogs housed in double compartment kennels.

    Directory of Open Access Journals (Sweden)

    Denae Wagner

    Full Text Available For animals in confinement housing the housing structure has tremendous potential to impact well being. Dogs in animal shelters are often housed in one of two types of confinement housing - single kennels and rooms or double compartment kennels and rooms most often separated by a guillotine door. This study examines the effect of housing on the location of elimination behavior in dogs housed in double compartment kennels were the majority of the dogs were walked daily. One side of the kennel contained the food, water and bed and the other side was empty and available except during cleaning time. Location of urination and defecation was observed daily for 579 dogs housed in indoor double compartment kennels for a total of 4440 days of observation. There were 1856 days (41.9% when no elimination was noted in the kennel. Feces, urine or both were observed in the kennel on 2584 days (58.1%. When elimination occurred in the kennel the probability of fecal elimination on the opposite side of the bed/food/water was 72.5% (95% CI 69.05% to 75.69%. The probability of urination on the opposite side of the bed/food/water was 77.4% (95% CI 74.33% to 80.07%. This study demonstrates the strong preference of dogs to eliminate away from the area where they eat, drink and sleep. Double compartment housing not only allows this - it allows staff the ability to provide safe, efficient, humane daily care and confers the added benefits of reducing risks for disease transmission for the individual dog as well as the population.

  18. Acute Compartment Syndrome of the Thigh in Combat Casualties (United States)


    of 30 (70%) patients required lower leg fasciotomy for acute compart- ment syndrome . Seven service members required forearm fasciotomies with four...Owen, C. A. Compartmental syndrome and its relation to the crush syndrome : a spectrum of disease. A review of 11 cases of prolonged limb compression...of compartmental syndromes . J. Bone Joint Surg. Am. 62:286–291, 1980. 28. Mubarak, S. J. A practical approach to compartmental syndromes : Part II

  19. Lysosome-related organelles: Unusual compartments become mainstream


    Marks, Michael S.; Heijnen, Harry F. G.; Raposo, Graça


    Lysosome-related organelles (LROs) comprise a group of cell type-specific subcellular compartments with unique composition, morphology and structure that share some features with endosomes and lysosomes and that function in varied processes such as pigmentation, hemostasis, lung plasticity and immunity. In recent years, studies of genetic diseases in which LRO functions are compromised have provided new insights into the mechanisms of LRO biogenesis and the regulated secretion of LRO contents...

  20. Compartment syndrome after total knee arthroplasty: regarding a clinical case

    Directory of Open Access Journals (Sweden)

    Ana Alexandra da Costa Pinheiro


    Full Text Available ABSTRACT Although compartment syndrome is a rare complication of total knee arthroplasty, it is one of the most devastating complications. It is defined as a situation of increased pressure within a closed osteofascial space that impairs the circulation and the functioning of the tissues inside this space, thereby leading to ischemia and tissue dysfunction. Here, a clinical case of a patient who was followed up in orthopedic outpatient consultations due to right gonarthrosis is presented. The patient had a history of arthroscopic meniscectomy and presented knee flexion of 10° before the operation, which consisted of total arthroplasty of the right knee. The operation seemed to be free from intercurrences, but the patient evolved with compartment syndrome of the ipsilateral leg after the operation. Since compartment syndrome is a true surgical emergency, early recognition and treatment of this condition through fasciotomy is crucial in order to avoid amputation, limb dysfunction, kidney failure and death. However, it may be difficult to make the diagnosis and cases may not be recognized if the cause of compartment syndrome is unusual or if the patient is under epidural analgesia and/or peripheral nerve block, which thus camouflages the main warning sign, i.e. disproportional pain. In addition, edema of the limb that underwent the intervention is common after total knee arthroplasty operations. This study presents a review of the literature and signals that the possible rarity of cases is probably due to failure to recognize this condition in a timely manner and to placing these patients in other diagnostic groups that are less likely, such as neuropraxia caused by using a tourniquet or peripheral nerve injury.

  1. Elimination behavior of shelter dogs housed in double compartment kennels. (United States)

    Wagner, Denae; Newbury, Sandra; Kass, Philip; Hurley, Kate


    For animals in confinement housing the housing structure has tremendous potential to impact well being. Dogs in animal shelters are often housed in one of two types of confinement housing - single kennels and rooms or double compartment kennels and rooms most often separated by a guillotine door. This study examines the effect of housing on the location of elimination behavior in dogs housed in double compartment kennels were the majority of the dogs were walked daily. One side of the kennel contained the food, water and bed and the other side was empty and available except during cleaning time. Location of urination and defecation was observed daily for 579 dogs housed in indoor double compartment kennels for a total of 4440 days of observation. There were 1856 days (41.9%) when no elimination was noted in the kennel. Feces, urine or both were observed in the kennel on 2584 days (58.1%). When elimination occurred in the kennel the probability of fecal elimination on the opposite side of the bed/food/water was 72.5% (95% CI 69.05% to 75.69%). The probability of urination on the opposite side of the bed/food/water was 77.4% (95% CI 74.33% to 80.07%). This study demonstrates the strong preference of dogs to eliminate away from the area where they eat, drink and sleep. Double compartment housing not only allows this - it allows staff the ability to provide safe, efficient, humane daily care and confers the added benefits of reducing risks for disease transmission for the individual dog as well as the population.

  2. Infusoabdomen with abdominal compartment in extremely low birth weight neonates

    Directory of Open Access Journals (Sweden)

    Armin-Johannes Michel


    Full Text Available Central venous catheters (CVCs are frequently used in neonatal care. The rate of complications upon CVC use is high and the spectrum ranges from catheter tip dislocation to cardiac tamponade and death. Here we present an explanation model to the phenomenon of paravasate into human anatomical cavities based on two illustrative cases: Extremely low birth weight twins suffering from abdominal compartment syndromes due to different pathologies – one with a trans-peritoneal and one with intra-abdominal effusion. In both siblings the peripherally introduced central catheter (PICC perforated the vessel without clinical signs of bleeding and contributed to abdominal and thoracal complications. Case I (23 + 5 gestational week; 770 g; female showed clinical signs of an abdominal compartment syndrome without respective intestinal pathology upon open surgical procedure with ileostomy. Radiographic contrast examination showed retroperitoneal leakage when administered through the catheter. Replacement into the subclavian vein led to cardio-respiratory misbalance due to severe pleural effusion. Re-replacement finally led to clinical restitution after 60 days of intensive care. Case II (23 + 5 gestational week; 690 g; female showed clinical signs of an abdominal compartment syndrome, too. Radiographic contrast examination showed leakage from the PICC into the abdomen. Replacement of the PICC and invasive care led to improvement after 3 days. The 2 cases reveal that the displacement of a PICC can occur without direct clinical signs of hemodynamic imbalance i.e. bleeding or hematoma. Displacement of the catheter tip from intra-vascular, retro-peritoneal position can cause abdominal compartment syndromes either via trans-peritoneal migration of fluids or after perforation of the peritoneum via intra-abdominal administration of given infusion. Both options caused life threatening complications. Watchfulness and intensive surgical and non-surgical care are

  3. High Flux Isotope Reactor (HFIR) (United States)

    Federal Laboratory Consortium — The HFIR at Oak Ridge National Laboratory is a light-water cooled and moderated reactor that is the United States’ highest flux reactor-based neutron source. HFIR...

  4. Reactor operation environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Haselow, J.S.; Price, V.; Stephenson, D.E.; Bledsoe, H.W.; Looney, B.B.


    The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimal impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.

  5. The pseudo-compartment method for coupling partial differential equation and compartment-based models of diffusion. (United States)

    Yates, Christian A; Flegg, Mark B


    Spatial reaction-diffusion models have been employed to describe many emergent phenomena in biological systems. The modelling technique most commonly adopted in the literature implements systems of partial differential equations (PDEs), which assumes there are sufficient densities of particles that a continuum approximation is valid. However, owing to recent advances in computational power, the simulation and therefore postulation, of computationally intensive individual-based models has become a popular way to investigate the effects of noise in reaction-diffusion systems in which regions of low copy numbers exist. The specific stochastic models with which we shall be concerned in this manuscript are referred to as 'compartment-based' or 'on-lattice'. These models are characterized by a discretization of the computational domain into a grid/lattice of 'compartments'. Within each compartment, particles are assumed to be well mixed and are permitted to react with other particles within their compartment or to transfer between neighbouring compartments. Stochastic models provide accuracy, but at the cost of significant computational resources. For models that have regions of both low and high concentrations, it is often desirable, for reasons of efficiency, to employ coupled multi-scale modelling paradigms. In this work, we develop two hybrid algorithms in which a PDE in one region of the domain is coupled to a compartment-based model in the other. Rather than attempting to balance average fluxes, our algorithms answer a more fundamental question: 'how are individual particles transported between the vastly different model descriptions?' First, we present an algorithm derived by carefully redefining the continuous PDE concentration as a probability distribution. While this first algorithm shows very strong convergence to analytical solutions of test problems, it can be cumbersome to simulate. Our second algorithm is a simplified and more efficient implementation of

  6. Engineered protein nano-compartments for targeted enzyme localization.

    Directory of Open Access Journals (Sweden)

    Swati Choudhary

    Full Text Available Compartmentalized co-localization of enzymes and their substrates represents an attractive approach for multi-enzymatic synthesis in engineered cells and biocatalysis. Sequestration of enzymes and substrates would greatly increase reaction efficiency while also protecting engineered host cells from potentially toxic reaction intermediates. Several bacteria form protein-based polyhedral microcompartments which sequester functionally related enzymes and regulate their access to substrates and other small metabolites. Such bacterial microcompartments may be engineered into protein-based nano-bioreactors, provided that they can be assembled in a non-native host cell, and that heterologous enzymes and substrates can be targeted into the engineered compartments. Here, we report that recombinant expression of Salmonella enterica ethanolamine utilization (eut bacterial microcompartment shell proteins in E. coli results in the formation of polyhedral protein shells. Purified recombinant shells are morphologically similar to the native Eut microcompartments purified from S. enterica. Surprisingly, recombinant expression of only one of the shell proteins (EutS is sufficient and necessary for creating properly delimited compartments. Co-expression with EutS also facilitates the encapsulation of EGFP fused with a putative Eut shell-targeting signal sequence. We also demonstrate the functional localization of a heterologous enzyme (β-galactosidase targeted to the recombinant shells. Together our results provide proof-of-concept for the engineering of protein nano-compartments for biosynthesis and biocatalysis.

  7. Dynamically Active Compartments Coupled by a Stochastically Gated Gap Junction (United States)

    Bressloff, Paul C.; Lawley, Sean D.


    We analyze a one-dimensional PDE-ODE system representing the diffusion of signaling molecules between two cells coupled by a stochastically gated gap junction. We assume that signaling molecules diffuse within the cytoplasm of each cell and then either bind to some active region of the cell's membrane (treated as a well-mixed compartment) or pass through the gap junction to the interior of the other cell. We treat the gap junction as a randomly fluctuating gate that switches between an open and a closed state according to a two-state Markov process. This means that the resulting PDE-ODE is stochastic due to the presence of a randomly switching boundary in the interior of the domain. It is assumed that each membrane compartment acts as a conditional oscillator, that is, it sits below a supercritical Hopf bifurcation. In the ungated case (gap junction always open), the system supports diffusion-induced oscillations, in which the concentration of signaling molecules within the two compartments is either in-phase or anti-phase. The presence of a reflection symmetry (for identical cells) means that the stochastic gate only affects the existence of anti-phase oscillations. In particular, there exist parameter choices where the gated system supports oscillations, but the ungated system does not, and vice versa. The existence of oscillations is investigated by solving a spectral problem obtained by averaging over realizations of the stochastic gate.

  8. The statolith compartment in Chara rhizoids contains carbohydrate and protein (United States)

    Wang-Cahill, F.; Kiss, J. Z.


    In contrast to higher plants, the alga Chara has rhizoids with single membrane-bound compartments that function as statoliths in gravity perception. Previous work has demonstrated that these statoliths contain barium sulfate crystals. In this study, we show that statoliths in Chara rhizoids react with a Coomassie Brilliant Blue cytochemical stain for proteins. While statoliths did not react with silver methenamine carbohydrate cytochemistry, the monoclonal antibody CCRC-M2, which is against a carbohydrate (sycamore-maple rhamnogalacturonan I), labeled the statolith compartment. These results demonstrate that in addition to barium sulfate, statoliths in Chara rhizoids have an organic matrix that consists of protein and carbohydrate moieties. Since the statoliths were silver methenamine negative, the carbohydrate in this compartment could be a 3-linked polysaccharide. CCRC-M2 also labeled Golgi cisternae, Golgi-associated vesicles, apical vesicles, and cell walls in the rhizoids. The specificity of CCRC-M2 immunolabeling was verified by several control experiments, including the demonstration that labeling was abolished when the antibody was preabsorbed with its antigen. Since in this and a previous study (John Z. Kiss and L. Andrew Staehelin, American Journal of Botany 80: 273-282, 1993) antibodies against higher plant carbohydrates crossreacted with cell walls of Chara in a specific manner, Characean algae may be a useful model system in biochemical and molecular studies of cell walls.

  9. Hypothyroid-induced acute compartment syndrome in all extremities. (United States)

    Musielak, Matthew C; Chae, Jung Hee


    Acute compartment syndrome (ACS) is an uncommon complication of uncontrolled hypothyroidism. If unrecognized, this can lead to ischemia, necrosis and potential limb loss. A 49-year-old female presented with the sudden onset of bilateral lower and upper extremity swelling and pain. The lower extremity anterior compartments were painful and tense. The extensor surface of the upper extremities exhibited swelling and pain. Motor function was intact, however, limited due to pain. Bilateral lower extremity fasciotomies were performed. Postoperative Day 1, upper extremity motor function decreased significantly and paresthesias occurred. She therefore underwent bilateral forearm fasciotomies. The pathogenesis of hypothyroidism-induced compartment syndrome is unclear. Thyroid-stimulating hormone-induced fibroblast activation results in increased glycosaminoglycan deposition. The primary glycosaminoglycan in hypothyroid myxedematous changes is hyaluronic acid, which binds water causing edema. This increases vascular permeability, extravasation of proteins and impaired lymphatic drainage. These contribute to increased intra-compartmental pressure and subsequent ACS. Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author 2016.

  10. Volkmann's ischemia. A volar compartment syndrome of the forearm. (United States)

    Eaton, R G; Green, W T


    In a series of 19 patients with Volkmann's iscemia, 63 per cent had suffered skeletal trauma, whereas 38 per cent had received non-skeletal trauma. Non-specific trauma may trigger an ischemia-edema cycle, producing increased intracompartmental pressure. This cycle, if unrelieved, can involve all of the muscles in the compartment, via cyclic propagation and reinforcement of arterial spasm. The volar compartmental syndrome is not an all or none phenomenon. Localized ischemia may trigger a gradually spreading arterial spasm which results in slowly progressive clinical changes as late as 3-4 months after onset. Decompression not only of the compartment but of each individual muscle which shows evidence of vascular compromise, may reverse this destructive cycle even as late as 3-4 months but it should be performed promptly with the onset of symptoms, when its effect is rapid and dramatic. Induration of the compartment is pathognomonic of the compartmental syndrome. As long as it is present, benefit can be expected from decompression procedures. Regeneration of necrotic ischemic muscle is possible following restoration of circulation.

  11. Digital Microscopy Assessment of Angiogenesis in Different Breast Cancer Compartments

    Directory of Open Access Journals (Sweden)

    Anca Haisan


    Full Text Available Background/Aim. Tumour angiogenesis defined by microvessel density (MVD is generally accepted as a prognostic factor in breast cancer. However, due to variability of measurement systems and cutoffs, it is questionable to date whether it contributes to predictive outline. Our study aims to grade vascular heterogeneity by comparing clear-cut compartments: tumour associated stroma (TAS, tumour parenchyma, and tumour invasive front. Material and Methods. Computerized vessel area measurement was performed using a tissue cytometry system (TissueFAXS on slides originated from 50 patients with breast cancer. Vessels were marked using immunohistochemistry with CD34. Regions of interest were manually defined for each tumour compartment. Results. Tumour invasive front vascular endothelia area was 2.15 times higher than that in tumour parenchyma and 4.61 times higher than that in TAS (P<0.002. Worth to mention that the lymph node negative subgroup of patients show a slight but constant increase of vessel index in all examined compartments of breast tumour. Conclusion. Whole slide digital examination and region of interest (ROI analysis are a valuable tool in scoring angiogenesis markers and disclosing their prognostic capacity. Our study reveals compartments’ variability of vessel density inside the tumour and highlights the propensity of invasive front to associate an active process of angiogenesis with potential implications in adjuvant therapy.

  12. Chronic Exertional Compartment Syndrome in a High School Soccer Player

    Directory of Open Access Journals (Sweden)

    James J. Bresnahan


    Full Text Available Chronic exertional compartment syndrome (CECS is a relatively rare condition that affects young adult athletes and often causes them to present to the emergency department. If left untreated, those who continue to compete at high levels may experience debilitating leg pain. Physicians may have difficulty differentiating CECS from other syndromes of the lower leg such as medial tibial stress syndrome, stress fractures, and popliteal artery entrapment. The gold standard for diagnosing CECS is intramuscular compartment pressure monitoring before and/or after 10 minutes of exercise. Some patients may choose to stop participation in sports in order to relieve their pain, which otherwise does not respond well to nonoperative treatments. In patients who wish to continue to participate in sports and live an active life, fasciotomy provides relief in 80% or more. The typical athlete can return to training in about 8 weeks. This is a case of a high school soccer player who stopped competing due to chronic exertional compartment syndrome. She had a fascial hernia, resting intramuscular pressure of 30 mmHg, and postexercise intramuscular pressure of 99 mmHg. Following fasciotomy she experienced considerable life improvement and is once again training and playing soccer without symptoms.

  13. Surgical management of exertional anterior compartment syndrome of the leg. (United States)

    Ali, T; Mohammed, F; Mencia, M; Maharaj, D; Hoford, R


    To describe the characteristic presentation of exertional leg pain in athletes and to discuss the diagnostic options and surgical management of exertional anterior compartment syndrome of the leg in this group of patients. Data from a series of athletes presenting with exertional leg pain were analysed and categorized according to aetiology. Sixty-six athletes presenting with exertional leg pain in 102 limbs were analysed. Sixteen patients in a first group of 20 patients with a provisional diagnosis of exertional anterior compartment syndrome of the leg underwent a closed fasciotomy with complete resolution of symptoms. A second group of 42 patients were diagnosed as medial tibial stress syndrome and a third group of four patients had confirmed stress fracture of the tibia. Exertional leg pain is a common presenting complaint of athletes to sports physicians and physiotherapists. Careful analysis can lead to an accurate diagnosis and commencement of effective treatment. Exertional anterior compartment syndrome can be successfully treated utilizing a closed fasciotomy with a rapid return to sport.

  14. Reactor operation safety information document

    Energy Technology Data Exchange (ETDEWEB)


    The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

  15. Chronic compartment syndrome of the forearm in competitive motor cyclists: a report of two cases. (United States)

    Goubier, J N; Saillant, G


    Exertional compartment syndrome of the forearm is rare. However, it should be considered in cases of a painful forearm during motorcycle racing. Pressure measurements of all compartments during exercises that simulate the actions of racing confirm the diagnosis. An exertional electromyography may be useful to reveal a nerve compression associated with the compartment syndrome. Fasciotomy of the affected compartments allows relief of symptoms and return to previous activities in all cases.

  16. Impact of protein binding on receptor occupancy: A two-compartment model


    Peletier, Lambertus A.; Benson, Neil; Van Der Graaf, Piet H.


    Abstract In this paper we analyse the impact of protein- and lipid- and receptor-binding on receptor occupancy in a two-compartment system, with proteins in both compartments and lipids and receptors in the peripheral compartment only. We do this for two manners of drug administration: a bolus administration and a constant rate infusion, both into the central compartment. We derive explicit approximations for the time-curves of the different compounds valid for a wide range of real...

  17. Fast reactor programme in India

    Indian Academy of Sciences (India)


    Sep 4, 2015 ... criteria; passive shutdown and decay heat removal systems; fast breeder reactors in India. PACS No. 28.41.−i. 1. ... water reactors, mainly pressurized heavy water reactors (PHWRs) to extract ∼10 GWe capacity for ..... commissioning phase and most of the supporting systems have been commissioned and.

  18. Engineering reactors for catalytic reactions

    Indian Academy of Sciences (India)

    Extensive studies have been conducted to establish sound basis for design and engineering of reactors for practising such catalytic reactions and for realizing improvements in reactor performance. In this article, application of recent (and not so recent) developments in engineering reactors for catalytic reactions is ...


    Whitham, G.K.; Smith, R.R.


    This patent shows a method for detecting leaks in jacketed fuel elements. The element is placed in a sealed tank within a nuclear reactor, and, while the reactor operates, the element is sparged with gas. The gas is then led outside the reactor and monitored for radioactive Xe or Kr. (AEC)

  20. Fast reactor programme in India

    Indian Academy of Sciences (India)


    Sep 4, 2015 ... Home; Journals; Pramana – Journal of Physics; Volume 85; Issue 3. Fast reactor programme in India. P Chellapandi P R ... Keywords. Sodium fast reactor; design challenges; construction challenges; emerging safety criteria; passive shutdown and decay heat removal systems; fast breeder reactors in India.