Sample records for bypass filter technology

  1. Oil Bypass Filter Technology Performance Evaluation - January 2003 Quarterly Report

    Energy Technology Data Exchange (ETDEWEB)

    Laurence R. Zirker; James E. Francfort


    This report details the initial activities to evaluate the performance of the oil bypass filter technology being tested by the Idaho National Engineering and Environmental Laboratory (INEEL) for the U.S. Department of Energy's FreedomCAR & Vehicle Technologies Program. Eight full-size, four-cycle diesel-engine buses used to transport INEEL employees on various routes have been equipped with oil bypass systems from the puraDYN Corporation. Each bus averages about 60,000 miles a year. The evaluation includes an oil analysis regime to monitor the presence of necessary additives in the oil and to detect undesirable contaminants. Very preliminary economic analysis suggests that the oil bypass system can reduce life-cycle costs. As the evaluation continues and oil avoidance costs are quantified, it is estimated that the bypass system economics may prove increasingly favorable, given the anticipated savings in operational costs and in reduced use of oil and waste oil avoidance.

  2. Oil Bypass Filter Technology Performance Evaluation - First Quarterly Report

    Energy Technology Data Exchange (ETDEWEB)

    Zirker, L.R.; Francfort, J.E.


    This report details the initial activities to evaluate the performance of the oil bypass filter technology being tested by the Idaho National Engineering and Environmental Laboratory (INEEL) for the U.S. Department of Energy's FreedomCAR & Vehicle Technologies Program. Eight full-size, four-cycle diesel-engine buses used to transport INEEL employees on various routes have been equipped with oil bypass systems from the puraDYN Corporation. Each bus averages about 60,000 miles a year. The evaluation includes an oil analysis regime to monitor the presence of necessary additives in the oil and to detect undesirable contaminants. Very preliminary economic analysis suggests that the oil bypass system can reduce life-cycle costs. As the evaluation continues and oil avoidance costs are quantified, it is estimated that the bypass system economics may prove increasingly favorable, given the anticipated savings in operational costs and in reduced use of oil and waste oil avoidance.

  3. Oil Bypass Filter Technology Evaluation - Third Quarterly Report, April--June 2003

    Energy Technology Data Exchange (ETDEWEB)

    Laurence R. Zirker; James E. Francfort


    This Third Quarterly report details the ongoing fleet evaluation of an oil bypass filter technology by the Idaho National Engineering and Environmental Laboratory (INEEL) for the U.S. Department of Energy’s FreedomCAR & Vehicle Technologies Program. Eight full-size, four-cycle diesel-engine buses used to transport INEEL employees on various routes have been equipped with oil bypass filter systems from the PuraDYN Corporation. The reported engine lubricating oil-filtering capability (down to 0.1 microns) and additive package of the bypass filter system is intended to extend oil-drain intervals. To validate the extended oil-drain intervals, an oil-analysis regime monitors the presence of necessary additives in the oil, detects undesirable contaminants and engine wear metals, and evaluates the fitness of the oil for continued service. The eight buses have accumulated 185,000 miles to date without any oil changes. The preliminary economic analysis suggests that the per bus payback point for the oil bypass filter technology should be between 108,000 miles when 74 gallons of oil use is avoided and 168,000 miles when 118 gallons of oil use is avoided. As discussed in the report, the variation in the payback point is dependant on the assumed cost of oil. In anticipation of also evaluating oil bypass systems on six Chevrolet Tahoe sport utility vehicles, the oil is being sampled on the six Tahoes to develop an oil characterization history for each engine.

  4. U.S. Department of Energy FreedomCAR & Vehicle Technologies Program Oil Bypass Filter Technology Evaluation Final Report

    Energy Technology Data Exchange (ETDEWEB)

    L. R. Zirker; J. E. Francfort; J. J. Fielding


    This Oil Bypass Filter Technology Evaluation final report documents the feasibility of using oil bypass filters on 17 vehicles in the Idaho National Laboratory (INL) fleet during a 3-year test period. Almost 1.3 million test miles were accumulated, with eleven 4-cycle diesel engine buses accumulating 982,548 test miles and six gasoline-engine Chevrolet Tahoes accumulating 303,172 test miles. Two hundred and forty oil samples, taken at each 12,000-mile bus servicing event and at 3,000 miles for the Tahoes, documented the condition of the engine oils for continued service. Twenty-eight variables were normally tested, including the presence of desired additives and undesired wear metals such as iron and chrome, as well as soot, water, glycol, and fuel. Depending on the assumptions employed, the INL found that oil bypass filter systems for diesel engine buses have a positive payback between 72,000 and 144,000 miles. For the Tahoes, the positive payback was between 66,000 and 69,000 miles.

  5. U.S. Department of Energy FreedomCAR & Vehicle Technologies Program Oil Bypass Filter Technology Evaluation - Sixth Quarterly Report, January - March 2004

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Department of Energy; Larry Zirker


    This Oil Bypass Filter Technology Evaluation quarterly report (January-March 2004) details the ongoing fleet evaluation of an oil bypass filter technology by the Idaho National Engineering and Environmental Laboratory (INEEL) for the U.S. Department of Energy's FreedomCAR & Vehicle Technologies Program. Eight four-cycle diesel-engine buses used to transport INEEL employees on various routes have been equipped with oil bypass filter systems from the puraDYN Corporation. The bypass filters are reported to have engine oil filtering capability of <1 micron and a built-in additive package to facilitate extended oil-drain intervals. This quarter, the heavy-duty buses traveled 88,747 miles, and as of the end of March 2004, the eight buses have accumulated 412,838 total test miles without requiring an oil change. This represents an avoidance of 34 oil changes, which equates to 1,199 quarts (300 gallons) of new oil not consumed and, furthermore, 1,199 quarts of waste oil not generated.

  6. Comparison of New Technology Integrated and Nonintegrated Arterial Filters Used in Cardiopulmonary Bypass Surgery: A Randomized, Prospective, and Single Blind Study

    Directory of Open Access Journals (Sweden)

    Özgür Gürsu


    Full Text Available Background. Innovative cardiopulmonary bypass (CPB settings have been developed in order to integrate the concepts of “surface-coating,” “blood-filtration,” and “miniaturization.” Objectives. To compare integrated and nonintegrated arterial line filters in terms of peri- and postoperative clinical variables, inflammatory response, and transfusion needs. Material and Methods. Thirty-six patients who underwent coronary bypass surgery were randomized into integrated (Group In and nonintegrated arterial line filter (Group NIn groups. Arterial blood samples for the assessments of complete hemogram, biochemical screening, interleukin-6, interleukin-2R, and C-reactive protein were analyzed before and after surgery. Need for postoperative dialysis, inotropic therapy and transfusion, in addition to extubation time, total amount of drainage (mL, length of intensive care unit, and hospital stay, and mortality rates was also recorded for each patient. Results. Prime volume was significantly higher and mean intraoperative hematocrit value was lower in Group NIn, but need for erythrocyte transfusion was significantly higher in Group NIn. C-reactive protein values did not differ significantly except for postoperative second day's results, which were found significantly lower in Group In than in Group NIn. Conclusion. Intraoperative hematocrit levels were higher and need for postoperative erythrocyte transfusion was decreased in Group In.

  7. 21 CFR 870.4260 - Cardiopulmonary bypass arterial line blood filter. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass arterial line blood filter... Cardiopulmonary bypass arterial line blood filter. (a) Identification. A cardiopulmonary bypass arterial line... entitled “Guidance for Cardiopulmonary Bypass Arterial Line Blood Filter 510(k) Submissions.” [45 FR 7907...

  8. 21 CFR 870.4270 - Cardiopulmonary bypass cardiotomy suction line blood filter. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass cardiotomy suction line... Devices § 870.4270 Cardiopulmonary bypass cardiotomy suction line blood filter. (a) Identification. A cardiopulmonary bypass cardiotomy suction line blood filter is a device used as part of a gas exchange (oxygenator...

  9. Sand Filter Technology (United States)


    EXWC) performed the evaluation at the Naval Air Station Lemoore, CA . The two year evaluation period began with one year of sand filter operation...appear dirty? If you answered “ yes ” to the first question and “ yes ” to either of the other questions, investigate this technology for your

  10. Reduced embolic load during clinical cardiopulmonary bypass using a 20 micron arterial filter. (United States)

    Jabur, G N S; Willcox, T W; Zahidani, S H; Sidhu, K; Mitchell, S J


    To compare the efficiency of 20 and 40 µm arterial line filters during cardiopulmonary bypass for the removal of emboli from the extracorporeal circuit. Twenty-four adult patients undergoing surgery were perfused using a cardiopulmonary bypass circuit containing either a 20 µm or 40 µm arterial filter (n = 12 in both groups). The Emboli Detection and Classification system was used to count emboli upstream and downstream of the filter throughout cardiopulmonary bypass. The mean proportion of emboli removed by the filter was compared between the groups. The 20 µm filter removed a significantly greater proportion of incoming emboli (0.621) than the 40 µm filter (0.334) (p=0.029). The superiority of the 20 µm filter persisted across all size groups of emboli larger than the pore size of the 40 µm filter. The 20 µm filter removed substantially more emboli than the 40 µm filter during cardiopulmonary bypass in this comparison.

  11. Arterial Filter Bypass Loop: What Occurs in this Area during Cardiopulmonary Bypass and Are There Potential Patient Implications (United States)

    Hawkins, Justin L.; Myers, Gerard J.; Légaré, Jean-Francois; Swyer, Wilfred


    Abstract: The arterial filter is an integral part of bypass circuitry. When introduced, manufacturers suggested a bypass loop for retrograde priming and de-airing, and for uninterrupted blood flow in case of malfunction. Practice has shown antegrade priming and de-airing is possible. This questions the necessity of the loop and presents the question—what occurs in the loop during bypass? After obtaining Human Research Ethics Board approval, eight consecutive patients (n = 8) were chosen for this study. Exclusive exclusion criterion was receiving any transfusions during cardiopulmonary bypass, as this could possibly influence results. The choice of patient numbers was based simply on proof of concept. Investigation involved isolation and collection of loop contents after cardiopulmonary bypass was completed. Testing included complete blood count, prothrombin time, international normalized ratio, partial thromboplastin time, activated clotting time, plasma free hemoglobin, slide photography with analysis for platelet clumping, and debris detection. One perfusionist collected samples, providing uniform collection and isolation technique. Regular blood samples were collected from the bypass circuitry, and from patients’ pre-operative blood work. Analysis of data revealed that platelet counts in the bypass loops were statistically lower than control. Evidence of platelet clumping was present in 3 of 8 bypass loop samples, representing 37.5% of the study population. There was no clumping detected in any of the controls. In patients where platelet clumping was present, a positive correlation was noted between mean bypass time and size of platelet clumps. Prothrombin time and international normalized ratio results were immeasurable. Hemoglobin levels were higher in the loop samples. There was no evidence of debris or fibrin monomer present in any of the samples analyzed. The study results indicate that during “normal” cardiopulmonary bypass with an arterial filter

  12. Ceramic fiber filter technology

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, B.L.; Janney, M.A.


    Fibrous filters have been used for centuries to protect individuals from dust, disease, smoke, and other gases or particulates. In the 1970s and 1980s ceramic filters were developed for filtration of hot exhaust gases from diesel engines. Tubular, or candle, filters have been made to remove particles from gases in pressurized fluidized-bed combustion and gasification-combined-cycle power plants. Very efficient filtration is necessary in power plants to protect the turbine blades. The limited lifespan of ceramic candle filters has been a major obstacle in their development. The present work is focused on forming fibrous ceramic filters using a papermaking technique. These filters are highly porous and therefore very lightweight. The papermaking process consists of filtering a slurry of ceramic fibers through a steel screen to form paper. Papermaking and the selection of materials will be discussed, as well as preliminary results describing the geometry of papers and relative strengths.


    The Filter Flow Technology, Inc. (FFT) Colloid Polishing Filter Method (CPFM) was tested as a transportable, trailer mounted, system that uses sorption and chemical complexing phenomena to remove heavy metals and nontritium radionuclides from water. Contaminated waters can be pro...

  14. Pulsatile flow decreases gaseous micro-bubble filtering properties of oxygenators without integrated arterial filters during cardiopulmonary bypass (United States)

    Milano, Aldo D.; Dodonov, Mikhail; Onorati, Francesco; Menon, Tiziano; Gottin, Leonardo; Malerba, Giovanni; Mazzucco, Alessandro; Faggian, Giuseppe


    OBJECTIVES Cardiopulmonary bypass (CPB) has a risk of embolic injury with an important role of gaseous micro-bubbles (GMBs), coming from CPB-circuit. Pulsatile perfusion (PP) can provide specific conditions for supplementary GMB-activity with respect to non-pulsatile (NP). We aimed to test GMB-filtering properties of three modern oxygenators under pulsatile and non-pulsatile conditions. METHODS Seventy-eight patients undergoing on-pump myocardial revascularization were randomized prospectively into three equal groups according to the oxygenator model used during CPB. Terumo Capiox-FX25, Sorin Synthesis or Maquet Quadrox-i-Adult membrane oxygenators were tested. Each group was divided equally to undergo PP or NP. GMBs were counted by means of a GAMPT-BCC200 bubble-counter with two probes placed at preoxygenator and arterial post-filter positions. Results were evaluated in terms of GMB-volume, GMB-number, amount of large over-ranged GMBs, a series of filtering indices and major neurological outcomes. RESULTS PP decreased GMB-filtering properties of the tested oxygenators. Those with integrated filters (CAPIOX-FX25 and SYNTHESIS) did not show significant differences between perfusion groups, while QUADROX-i oxygenator with external arterial filter showed significantly higher GMB-volume (P bubbles (P filtering capacity of all circuits with both types of perfusion, no important differences in clinical outcomes and major neurological events were observed. CONCLUSIONS Pulsatile flow decreases gaseous micro-bubble filtering properties of oxygenators without integrated arterial filters during CPB. PP requires specially designed circuit components to avoid the risk of additional GMB delivery. PMID:23842758


    The Filter Flow Technology, Inc. (FFT) Coloid Polishing Filter Method (CPFM) was demonstrated at the U.S Department of Energy's (DOE) Rock Flats Plant (RFP) as part of the U.S. Environmental Protection Agency's (EPA) Superfund and Innovative Technology Evaluation (SITE) program. ...

  16. Dedusting and filtering technology; Entstaubungs- und Filtertechnik

    Energy Technology Data Exchange (ETDEWEB)

    Selck, S.; Stockmann, H.W.; Both, R. [Deutsche Montan Technologie GmbH, Essen (Germany). Gas and Fire Div.


    For the further development of the filtration and dedusting technology within the last research period the new regulations in occupational hygiene concerning dust as well as ISO and EN standards have been considered. Also the new requirements concerning fire and explosion protection filter materials based in the test regulations for synthetic materials have been taken into account. The adoption of these new regulations inhibits the further use of the available high effective filter materials in underground coal mines. The development of new filter materials has been forced by the test regulations for synthetic materials, as the specific aspects of electrostatic behaviour, soot and toxic gases formed by burning of filter materials impacting the CO self rescue filters, have been taken into account. Even these requirements are partially inhibiting high filter efficiencies and air flows, all the requirements have been fulfilled on a high level on filter efficiencies matching the present state of art in occupational hygiene as reported in the Silicosis Reports Vol. 20 and 21. (orig.)


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of th...

  18. Dust removal and filter technology. Entstaubungs- und Filtertechnik

    Energy Technology Data Exchange (ETDEWEB)

    Stockmann, H.W. (DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany). DMT-Institut fuer Staubbekaempfung, Gefahrstoffe und Ergonomie); Henke, B. (DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany). DMT-Institut fuer Staubbekaempfung, Gefahrstoffe und Ergonomie)


    New approaches were adopted in filter technology to respond to technological changes in mechanized mining and to allow perfect dust removal in keeping with occupational hygiene requirements. Self-supporting filter materials based on ceramic fibres and synthetic granulates were taken to develop filter elements allowing lamination to enhance their separation-active surface area. Filter materials made from thermally fixed fibre nonwovens were processed to form plicated filter bags of the same structural volume but with a surface area increased by a factor of 2.5. Integrated inlet nozzles were developed to allow these elements to be cleaned of dust deposits. These nozzles were also studied in basic filter-technology tests. A test rig supplied design findings which were included in a study to develop new generations of dedusters. A reduction of design volume and an increase of through-put rate greater than 20% could be predicted. Service tests with modified filter materials were run for ventilation-air dust dust removal both for whole faces and for face segments. The benefits of filter technology for face, face opening and drifting were highlighted. New methods for wetting and transport of the dust removed from the dedusters were developed. New concepts of exhaust-air filter separators allow flat storage bunkers to be used in pneumatic conveyance of building materials at the face. (orig.)

  19. The Promise and Challenges of Ultra High Bypass Ratio Engine Technology and Integration (United States)

    Hughes, Chris


    In this presentation, an overview of the research being conducted by the ERA Project in Ultra High Bypass aircraft propulsion and in partnership with Pratt & Whitney with their Geared TurboFan (GTF) is given. The ERA goals are shown followed by a discussion of what areas need to be addressed on the engine to achieve the goals and how the GTF is uniquely qualified to meet the goals through a discussion of what benefits the cycle provides. The first generation GTF architecture is then shown highlighting the areas of collaboration with NASA, and the fuel burn, noise and emissions reductions possible based on initial static ground test and flight test data of the first GTF engine. Finally, a 5 year technology roadmap is presented focusing on Ultra High Bypass propulsion technology research areas that are being pursued and being planned by ERA and P&W under their GTF program.

  20. Internet Filtering Technology and Aversive Online Experiences in Adolescents. (United States)

    Przybylski, Andrew K; Nash, Victoria


    To evaluate the effectiveness of Internet filtering tools designed to shield adolescents from aversive experiences online. A total of 1030 in-home interviews were conducted with early adolescents aged from 12 to 15 years (M = 13.50, SD = 1.18) and their caregivers. Caregivers were asked about their use of Internet filtering and adolescent participants were interviewed about their recent online experiences. Contrary to our hypotheses, policy, and industry advice regarding the assumed benefits of filtering we found convincing evidence that Internet filters were not effective at shielding early adolescents from aversive online experiences. Preregistered prospective and randomised controlled trials are needed to determine the extent to which Internet filtering technology supports vs thwarts young people online and if their widespread use justifies their financial and informational costs. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Noise resonance : Technological sound reproduction and the logic of filtering

    NARCIS (Netherlands)

    Kromhout, M.J.


    What is it about noise that attracted musicians and listeners over the past century? Noise Resonance: Technological Sound Reproduction and the Logic of Filtering sets out to answer this question through an extensive conceptual revaluation of the role of noise and distortion in sound and music. The


    The CPFM technology is designed to remove trace to moderate levels of nontritium radionuclides and heavy metal pollutants from water. The technology uses a proprietary compound that consists of inorganic, oxide-based granules. This mixed is designed to remove heavy metals and rad...

  3. Drainage filter technologies to mitigate site-specific phosphorus losses

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Heckrath, Goswin Johann; Iversen, Bo Vangsø


    Drainage losses of phosphorus (P) contribute to an estimated load of 33% of total agricultural P losses in Denmark. Mitigating agricultural P losses is challenging, as critical P losses are only a small fraction of actual soil P contents and not directly related to fertilizer P input. Targeting......-specific nutrient losses in drainage. The “SUPREME-TECH” project (2010-2015), funded by the Danish Strategic Research Council, aims at providing the scientific basis for developing cost-effective drainage filter technologies to retain P in agricultural drainage waters. The project studies different approaches......-scale surface-flow constructed wetland. In the former, various natural and industrial P filter substrates have been tested for their ability to reduce inlet P concentrations to below environmental threshold values (phosphorus loads, hydraulic retention times, and flow regimes. Based...

  4. Metal-Mesh Optical Filter Technology for Mid IR, Far IR, and Submillimeter Project (United States)

    National Aeronautics and Space Administration — The innovative, high transmission band-pass filter technology proposed here is an improvement in multilayer metal-mesh filter design and manufacture for the far IR...

  5. Scientific Bases of Innovation Technology of Drill-Hole Equipment by Cryogenic-Gravel Filters

    Directory of Open Access Journals (Sweden)

    Коzhevnikov, А.А.


    Full Text Available Manufacturing technologies of cryogenic-gravel filter element and equipment of drill-hole water receiving part by a cryogenic-gravel filter are described. Compoundings of mineral binder and cryogenically-gravel composition are substantiated. Patterns of physical fields influence on the change of their properties and technological operations of equipping drill-hole water receiving part on changes of physical, mechanical, thermal and technological properties of experimental cryogenic gravel filter element are established. Parameters of delivery technology of cryogenicgravel filter to drill-hole water receiving part are theoretically and experimentally worked out.

  6. Evolution of membrane oxygenator technology for utilization during pediatric cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Melchior RW


    Full Text Available Richard W Melchior,1 Steven W Sutton,2 William Harris,3 Heidi J Dalton4,5 1Department of Perfusion Services, The Children's Hospital of Philadelphia, Philadelphia, PA, 2Cardiovascular Support Services, Inc., Dallas, TX, 3Department of Perfusion Services, Ochsner Clinic Foundation, New Orleans, LA, 4Alaskan Native Tribal Health Consortium, Anchorage, AK, 5Department of Child Health, University of Arizona-College of Medicine, Phoenix, AZ, USAAbstract: The development of the membrane oxygenator for pediatric cardiopulmonary bypass has been an incorporation of ideology and technological advancements with contributions by many investigators throughout the past two centuries. With the pursuit of this technological achievement, the ability to care for mankind in the areas of cardiac surgery has been made possible. Heart disease can affect anyone within the general population, but one such segment that it can affect from inception includes children. Currently, congenital heart defects are the most common birth defects nationally and worldwide. A large meta-analysis study from 1930 to 2010 was conducted in review of published medical literature totaling 114 papers with a study population of 24,091,867 live births, and divulged a staggering incidence of congenital heart disease involving 164,396 subjects with diverse cardiac illnesses. The prevalence of these diseases increased from 0.6 per 1,000 live births from 1930–1934 to 9.1 per 1,000 live births after 1995. These data reveal an emphasis on a growing public health issue regarding congenital heart disease. This discovery displays a need for heightened awareness in the scientific and medical industrial community to accelerate investigative research on emerging cardiovascular devices in an effort to confront congenital anomalies. One such device that has evolved over the past several decades is the pediatric membrane oxygenator. The pediatric membrane oxygenator, in conjunction with the heart lung


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of th...


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of th...

  9. Acoustic Performance of Novel Fan Noise Reduction Technologies for a High Bypass Model Turbofan at Simulated Flights Conditions (United States)

    Elliott, David M.; Woodward, Richard P.; Podboy, Gary G.


    Two novel fan noise reduction technologies, over the rotor acoustic treatment and soft stator vane technologies, were tested in an ultra-high bypass ratio turbofan model in the NASA Glenn Research Center s 9- by 15-Foot Low-Speed Wind Tunnel. The performance of these technologies was compared to that of the baseline fan configuration, which did not have these technologies. Sideline acoustic data and hot film flow data were acquired and are used to determine the effectiveness of the various treatments. The material used for the over the rotor treatment was foam metal and two different types were used. The soft stator vanes had several internal cavities tuned to target certain frequencies. In order to accommodate the cavities it was necessary to use a cut-on stator to demonstrate the soft vane concept.

  10. AEA Technologies Battery Cell By-pass Device Activation: An Update (United States)

    Keys, Denney; Rao, Gopalakrishna M.; Sullivan, David; Wannemacher, Harry; Day, John H. (Technical Monitor)


    The objectives are to: (1) Verify the Performance of AEA Cell Bypass Protection Device (CBPD) under simulated EOS-Aqua/Aura flight hardware configuration; (2) Assess the Safety of the hardware under an inadvertent firing of CBPD switch, as well as the closing of CBPD switch under simulated high cell impedance; and (3) Confirm that the mode of operation of CBPD switch is the formation of a continuous low impedance path (a homogeneous low melting point alloy).

  11. Feasibility of electro-osmotic belt filter dewatering technology at pilot scale

    CSIR Research Space (South Africa)

    Snyman, HG


    Full Text Available -effective dewatering technologies, electro-osmotic belt filtering was developed by Smollen and Kafaar in 1995. The mechanical equipment resembles a belt filter press but the belts are stainless steel, woven belts, which act as the electrodes. In this study...

  12. Development of a wavelength tunable filter using MEMS technology (United States)

    Liu, Junting

    Microelectromechanical systems (MEMS) for optical applications have received intensive attention in recent years because of their potential applications in optical telecommunication. Traditional wavelength division multiplexing (WDM) offers high capacity but requires the fabrication of selective add-drop filters. MEMS technology offers an effective way to fabricate these components at low cost. This thesis presents the development of a device that tunes the Bragg wavelength by coupling into the evanescent field of the grating. A Bragg grating is a periodic perturbation of the refractive index along a fiber or a periodic perturbation of the structure of a planar waveguide. The Bragg wavelength can be tuned by changing the degree to which a dielectric slab couples into the evanescent field. The result is a change in the effective index of the grating, and thus a change in the wavelength that which it reflects. In this thesis Bragg gratings were successfully written into an optical fiber using phase mask technique. Mechanical polishing was used to side-polish the fiber and remove cladding to expose the core. Grating structures were also fabricated in planar waveguide using E-beam writing and dry etching. In order to achieve the smoothest possible morphology of the waveguide, plasma dry etching of transparent substrates was studied in great detail. It is found that the pre-etch cleaning procedure greatly influences the ability to obtain a smooth etched surface. Upper limits of evanescent field tuning were investigated by applying different index liquids such as D. I. water and index matching oils or by positioning different dielectric materials such as glass and silicon close to the grating. Planar waveguides were found to be more sensitive to effective index change. Two kinds of computer simulation were carried out to understand the mode profile and to estimate the value of effective index of planar waveguide under "dry" and "wet" conditions. The first one used an

  13. Visible Wavelength Color Filters Using Dielectric Subwavelength Gratings for Backside-Illuminated CMOS Image Sensor Technologies. (United States)

    Horie, Yu; Han, Seunghoon; Lee, Jeong-Yub; Kim, Jaekwan; Kim, Yongsung; Arbabi, Amir; Shin, Changgyun; Shi, Lilong; Arbabi, Ehsan; Kamali, Seyedeh Mahsa; Lee, Hong-Seok; Hwang, Sungwoo; Faraon, Andrei


    We report transmissive color filters based on subwavelength dielectric gratings that can replace conventional dye-based color filters used in backside-illuminated CMOS image sensor (BSI CIS) technologies. The filters are patterned in an 80 nm-thick poly silicon film on a 115 nm-thick SiO2 spacer layer. They are optimized for operating at the primary RGB colors, exhibit peak transmittance of 60-80%, and have an almost insensitive response over a ± 20° angular range. This technology enables shrinking of the pixel sizes down to near a micrometer.

  14. Robotically Assisted Single Anastomosis Duodenoileal Bypass after Previous Sleeve Gastrectomy Implementing High Valuable Technology for Complex Procedures

    Directory of Open Access Journals (Sweden)

    Ramon Vilallonga


    Full Text Available Staged bariatric procedures in high risk patients are a common used strategy for morbid obese patients nowadays. After previous sleeve gastrectomy, surgical treatments in order to complete weight loss or comorbidities improvements or resolutions are possible. One strategy is to perform a novel technique named SADI (single anastomosis duodenoileal bypass-sleeve. We present the technique for totally intracorporeal robotically assisted SADI using five ports and a liver retractor. We aim to see if the robotic technology offers more advantageous anastomosis and dissection obtained by the robotic approach in comparison to standard laparoscopy. The safety, feasibility, and reproducibility of a minimally invasive robotic surgical approach to complex abdominal operations such as SADI are discussed.

  15. Removal of stormwater particulates by disc filter technology

    DEFF Research Database (Denmark)

    Nielsen, Katrine; Mikkelsen, Peter Steen; Eriksson, Eva

    The trend in the Danish society is toward disconnection of stormwater from the combined sewers and, where needed, local treatment using the best available technologies (BAT). The aim here was to assess a fast filtration technology for removal of particulate matter in stormwater with an emphasis...

  16. Circuit and Technology Considerations for High Frequency Switched-Capacitor Filters. (United States)

    Kaneshiro, Ronald Takeshi

    Since its inception in the late 1970's, the switched -capacitor filtering technique has been very widely applied in the telecommunications field. If this technique can be extended into a much higher frequency range, its applicability can be broadened into areas that are currently dominated by non-monolithic design methods. Past attempts to design practical and reproducible high frequency and high selectivity filters have been hindered by the problems related to the filter architecture, high speed monolithic amplifier design, and integrated circuit technology. In this dissertation the problems of high speed amplifier design and integrated circuit technology in relation to the realization of. practical high frequency switched-capacitor filters are addressed and investigated. *This research was sponsored by National Science Foundation Grant NSF ENG-7907055 and DARPA Grant N00039 -81-K-0251.

  17. Secondary and College LD Bypass Strategies. (United States)

    Mosby, Robert J.


    The author describes the Developmental By-Pass (DBP) Instructional technology for teaching secondary and college learning disabled (LD) students by allowing students to bypass ordering and organizational deficits. (SB)

  18. Effect of Two Advanced Noise Reduction Technologies on the Aerodynamic Performance of an Ultra High Bypass Ratio Fan (United States)

    Hughes, Christoper E.; Gazzaniga, John A.


    A wind tunnel experiment was conducted in the NASA Glenn Research Center anechoic 9- by 15-Foot Low-Speed Wind Tunnel to investigate two new advanced noise reduction technologies in support of the NASA Fundamental Aeronautics Program Subsonic Fixed Wing Project. The goal of the experiment was to demonstrate the noise reduction potential and effect on fan model performance of the two noise reduction technologies in a scale model Ultra-High Bypass turbofan at simulated takeoff and approach aircraft flight speeds. The two novel noise reduction technologies are called Over-the-Rotor acoustic treatment and Soft Vanes. Both technologies were aimed at modifying the local noise source mechanisms of the fan tip vortex/fan case interaction and the rotor wake-stator interaction. For the Over-the-Rotor acoustic treatment, two noise reduction configurations were investigated. The results showed that the two noise reduction technologies, Over-the-Rotor and Soft Vanes, were able to reduce the noise level of the fan model, but the Over-the-Rotor configurations had a significant negative impact on the fan aerodynamic performance; the loss in fan aerodynamic efficiency was between 2.75 to 8.75 percent, depending on configuration, compared to the conventional solid baseline fan case rubstrip also tested. Performance results with the Soft Vanes showed that there was no measurable change in the corrected fan thrust and a 1.8 percent loss in corrected stator vane thrust, which resulted in a total net thrust loss of approximately 0.5 percent compared with the baseline reference stator vane set.

  19. Removal of stormwater particulates by disc filter technology

    DEFF Research Database (Denmark)

    Nielsen, Katrine; Mikkelsen, Peter Steen; Eriksson, Eva

    and in the size-range of 100 nm. The physical treatment of particle filtration at 10 µm was inadequate to remove the small particles identified in this project. Coagulation with a cationic coagulant and subsequently flocculation is suggested as process improvements technologies....

  20. Drainage filter technologies to mitigate site-specific phosphorus losses in agricultural drainage discharge

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Heckrath, Goswin Johann; Canga, Eriona

    Losses of phosphorus (P) in drainage waters contribute an estimated 33% to the total agricultural P load in Denmark. Mitigating agricultural P losses is challenging, as critical P losses comprise only a very small fraction of actual soil P contents and are not directly related to fertilizer P input...... in drainage. The Danish “SUPREME-TECH” project (2010-2016) ( aims at providing the scientific basis for developing cost-effective filter technologies for P in agricultural drainage waters. The project studies different approaches of implementing filter technologies including drainage well...

  1. Protozoa and metazoa relations to technological conditions of non-woven textile filters for wastewater treatment. (United States)

    Spychała, Marcin; Sowińska, Aleksandra; Starzyk, Justyna; Masłowski, Adam


    The objective of this study was a preliminary identification of basic groups of micro-organisms in the cross-sectional profile of geotextile filters for septic tank effluent (STE) treatment and their relations to technological conditions. Reactors with textile filters treating wastewater were investigated on a semi-technical scale. Filters were vertically situated and STE was filtered through them under hydrostatic pressure at a wastewater surface height of 7-20 cm. Filters were made of four layers of non-woven TS 20 geotextile of 0.9 mm thickness. Various groups of organisms were observed; the most abundant group comprised free-swimming and crawling ciliates, less abundant were stalked ciliates and the least numerous were nematodes. The individual counts of all groups of micro-organisms investigated during the study were variable according to time and space. The high abundance of Opercularia, a commonly observed genus of stalked ciliates, was related to the high efficiency of wastewater treatment and dissolved oxygen concentration of about 1.0 g/m3. Numbers of free-swimming and crawling ciliates had a tendency to decrease in relation to the depth of filter cross-sectional profile. The variability in counts of particular groups of organisms could be related to the local stress conditions. No correlation between identified organism count and total mass concentration in the cross-sectional filter profile was found.

  2. Smart structures for application in ceramic barrier filter technology. Final report, August 1991--August 1994

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, S.J.; Lippert, T.E


    High temperature optical fiber sensors were developed to measure the in-service stressing that occurs in ceramic barrier filter systems. The optical fiber sensors were based on improvements to the sensor design developed under the DOE/METC Smart Structures for Fossil Energy Applications contract no. DE-AC21-89MC25159. In-house application testing of these sensors on both candle and cross-flow filters were performed in the Westinghouse Science and Technology Center High-Temperature, High-Pressure Filter Test Facility and the results analyzed. This report summarizes the sensor developments, methods to apply the sensors to the filters for in-situ testing, and the test results from the four in-house tests that were performed.

  3. The Society of Thoracic Surgeons, The Society of Cardiovascular Anesthesiologists, and The American Society of ExtraCorporeal Technology: Clinical Practice Guidelines for Cardiopulmonary Bypass--Temperature Management during Cardiopulmonary Bypass. (United States)

    Engelman, Richard; Baker, Robert A; Likosky, Donald S; Grigore, Alina; Dickinson, Timothy A; Shore-Lesserson, Linda; Hammon, John W


    To improve our understanding of the evidence-based literature supporting temperature management during adult cardiopulmonary bypass, The Society of Thoracic Surgeons, the Society of Cardiovascular Anesthesiology and the American Society of ExtraCorporeal Technology tasked the authors to conduct a review of the peer-reviewed literature, including 1) optimal site for temperature monitoring, 2) avoidance of hyperthermia, 3) peak cooling temperature gradient and cooling rate, and 4) peak warming temperature gradient and rewarming rate. Authors adopted the American College of Cardiology/American Heart Association method for development clinical practice guidelines, and arrived at the following recommendation.

  4. Heart bypass surgery (United States)

    Off-pump coronary artery bypass; OPCAB; Beating heart surgery; Bypass surgery - heart; CABG; Coronary artery bypass graft; Coronary artery bypass surgery; Coronary bypass surgery; Coronary artery disease - CABG; CAD - CABG; Angina - ...

  5. Gastric bypass surgery (United States)

    ... Y gastric bypass; Gastric bypass - Roux-en-Y; Weight-loss surgery - gastric bypass; Obesity surgery - gastric bypass Patient Instructions Bathroom safety - adults Gastric bypass surgery - discharge Laparoscopic gastric banding - discharge ...

  6. Application of Micropore Filter Technology: Exploring the Blood Flow Path in Arterial-Line Filters and Its Effect on Bubble Trapping Functions (United States)

    Herbst, Daniel P.


    Abstract: Conventional arterial-line filters commonly use a large volume circular shaped housing, a wetted micropore screen, and a purge port to trap, separate, and remove gas bubbles from extracorporeal blood flow. Focusing on the bubble trapping function, this work attempts to explore how the filter housing shape and its resulting blood flow path affect the clinical application of arterial-line filters in terms of gross air handling. A video camera was used in a wet-lab setting to record observations made during gross air-bolus injections in three different radially designed filters using a 30–70% glycerol–saline mixture flowing at 4.5 L/min. Two of the filters both had inlet ports attached near the filter-housing top with bottom oriented outlet ports at the bottom, whereas the third filter had its inlet and outlet ports both located at the bottom of the filter housing. The two filters with top-in bottom-out fluid paths were shown to direct the incoming flow downward as it passed through the filter, placing the forces of buoyancy and viscous drag in opposition to each other. This contrasted with the third filter's bottom-in bottom-out fluid path, which was shown to direct the incoming flow upward so that the forces of buoyancy and viscous drag work together. The direction of the blood flow path through a filter may be important to the application of arterial-line filter technology as it helps determine how the forces of buoyancy and flow are aligned with one another. PMID:28298665


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) Verification Center. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of the size of those particles equal to and smalle...


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) Verification Center. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of the size of those particles equal to and smalle...


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) Verification Center. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of the size of those particles equal to and smalle...


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of th...

  11. The impact of care management information technology model on quality of care after Coronary Artery Bypass Surgery: "Bridging the Divides". (United States)

    Weintraub, William S; Elliott, Daniel; Fanari, Zaher; Ostertag-Stretch, Jennifer; Muther, Ann; Lynahan, Margaret; Kerzner, Roger; Salam, Tabassum; Scherrer, Herbert; Anderson, Sharon; Russo, Carla A; Kolm, Paul; Steinberg, Terri H


    Reducing readmissions and improving metrics of care are a national priority. Supplementing traditional care with care management may improve outcomes. The Bridges program was an initial evaluation of a care management platform (CareLinkHub), supported by information technology (IT) developed to improve the quality and transition of care from hospital to home after Coronary Artery Bypass Surgery (CABG) and reduce readmissions. CareLink is comprised of care managers, patient navigators, pharmacists and physicians. Information to guide care management is guided by a middleware layer to gather information, PLR (ColdLight Solutions, LLC) and presented to CareLink staff on a care management platform, Aerial™ (Medecision). In addition there is an analytic engine to help evaluate and guide care, Neuron™ (Coldlight Solutions, LLC). The "Bridges" program enrolled a total of 716 CABG patients with 850 admissions from April 2013 through March 2015. The data of the program was compared with those of 1111 CABG patients with 1203 admissions in the 3years prior to the program. No impact was seen with respect to readmissions, Blood Pressure or LDL control. There was no significant improvement in patients' reported outcomes using either the CTM-3 or any of the SAQ-7 scores. Patient follow-up with physicians within 1week of discharge improved during the Bridges years. The CareLink hub platform was successfully implemented. Little or no impact on outcome metrics was seen in the short follow-up time. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Heart bypass surgery - discharge (United States)

    Off-pump coronary artery bypass - discharge; OPCAB - discharge; Beating heart surgery - discharge; Bypass surgery - heart - discharge; CABG - discharge; Coronary artery bypass graft - discharge; Coronary artery ...

  13. The Society of Thoracic Surgeons, The Society of Cardiovascular Anesthesiologists, and The American Society of ExtraCorporeal Technology: Clinical Practice Guidelines for Cardiopulmonary Bypass--Temperature Management During Cardiopulmonary Bypass. (United States)

    Engelman, Richard; Baker, Robert A; Likosky, Donald S; Grigore, Alina; Dickinson, Timothy A; Shore-Lesserson, Linda; Hammon, John W


    In order to improve our understanding of the evidence-based literature supporting temperature management during adult cardiopulmonary bypass, The Society of Thoracic Surgeons, the Society of Cardiovascular Anesthesiology and the American Society of ExtraCorporeal Technology tasked the authors to conduct a review of the peer-reviewed literature, including: 1) optimal site for temperature monitoring, 2) avoidance of hyperthermia, 3) peak cooling temperature gradient and cooling rate, and 4) peak warming temperature gradient and rewarming rate. Authors adopted the American College of Cardiology/American Heart Association method for development clinical practice guidelines, and arrived at the following recommendations: CLASS I RECOMMENDATIONS: a)The oxygenator arterial outlet blood temperature is recommended to be utilized as a surrogate for cerebral temperature measurement during CPB. (Class I, Level C) b)To monitor cerebral perfusate temperature during warming, it should be assumed that the oxygenator arterial outlet blood temperature under-estimates cerebral perfusate temperature. (Class I, Level C) c)Surgical teams should limit arterial outlet blood temperature to<37°C to avoid cerebral hyperthermia. (Class 1, Level C) d)Temperature gradients between the arterial outlet and venous inflow on the oxygenator during CPB cooling should not exceed 10°C to avoid generation of gaseous emboli. (Class 1, Level C) e)Temperature gradients between the arterial outlet and venous inflow on the oxygenator during CPB rewarming should not exceed 10°C to avoid out-gassing when blood is returned to the patient. (Class 1, Level C) CLASS IIa a)Pulmonary artery or nasopharyngeal temperature recording is reasonable for weaning and immediate post-bypass temperature measurement. (Class IIa, Level C)b)Rewarming when arterial blood outlet temperature ≥30° C: i.To achieve the desired temperature for separation from bypass, it is reasonable to maintain a temperature gradient between

  14. Airborne testing of the joint mine detection technology's tunable filter multispectral camera (United States)

    Crosby, Frank J.; Holloway, John H., Jr.; Petee, Danny A.; Stetson, Suzanne P.; Suiter, Harold R.; Tinsley, Ken R.


    The Joint Mine Detection Technology (JMDT) project, following successful field-based testing of its new Tunable Filter Multispectral Camera (TFMC) has now completed initial Airborne Testing of the TFMC at both the Coastal Systems Station and Eglin Air Force Base sites. An overview of the testing is presented along with the investigations into the advantages of a system utilizing the TFMC in airborne operational scenarios. The TFMC-like tuning flexibility was flight-tested using optimized wavelength combinations, which were found using field test data, over a variety of backgrounds and altitudes. The data revealed the suitability of background tuning, polarization, and mechanically co-registered channels as benefits to multispectral target detection. The data were also compared to that collected with an IMC-201 camera, using the six filters of the Coastal Battlefield Reconnaissance and Analysis (COBRA) Advanced Technology Demonstration (ATD) system, in order to determine improvements over existing capabilities.

  15. Technology optimization techniques for multicomponent optical band-pass filter manufacturing (United States)

    Baranov, Yuri P.; Gryaznov, Georgiy M.; Rodionov, Andrey Y.; Obrezkov, Andrey V.; Medvedev, Roman V.; Chivanov, Alexey N.


    Narrowband optical devices (like IR-sensing devices, celestial navigation systems, solar-blind UV-systems and many others) are one of the most fast-growing areas in optical manufacturing. However, signal strength in this type of applications is quite low and performance of devices depends on attenuation level of wavelengths out of operating range. Modern detectors (photodiodes, matrix detectors, photomultiplier tubes and others) usually do not have required selectivity or have higher sensitivity to background spectrum at worst. Manufacturing of a single component band-pass filter with high attenuation level of wavelength is resource-intensive task. Sometimes it's not possible to find solution for this problem using existing technologies. Different types of filters have technology variations of transmittance profile shape due to various production factors. At the same time there are multiple tasks with strict requirements for background spectrum attenuation in narrowband optical devices. For example, in solar-blind UV-system wavelengths above 290-300 nm must be attenuated by 180dB. In this paper techniques of multi-component optical band-pass filters assembly from multiple single elements with technology variations of transmittance profile shape for optimal signal-tonoise ratio (SNR) were proposed. Relationships between signal-to-noise ratio and different characteristics of transmittance profile shape were shown. Obtained practical results were in rather good agreement with our calculations.

  16. Coronary Artery Bypass Grafting (United States)

    ... Health Topics / Coronary Artery Bypass Grafting Coronary Artery Bypass Grafting What Is Coronary artery bypass grafting (CABG) ... multiple coronary arteries during one surgery. Coronary Artery Bypass Grafting Figure A shows the location of the ...

  17. Analysis of up-flow aerated biological activated carbon filter technology in drinking water treatment. (United States)

    Lu, Shaoming; Liu, Jincui; Li, Shaowen; Biney, Elizabeth


    Problems have been found in the traditional post-positioned down-flow biological activated carbon filter (DBACF), such as microorganism leakage and low biodegradability. A pilot test was carried out to place a BACF between the sediment tank and the sand filter; a new technology of dual media up-flow aerated biological activated carbon filter (UBACF) was developed. Results showed that in terms of the new process, the up-flow mode was better than the down-flow. Compared with the DBACF, the problem of microorganism leakage could be well resolved with the UBACF process by adding disinfectant before the sand filtration, and a similar adsorption effect could be obtained. For the tested raw water, the COD(Mn) and NH3-N removal rate was 54.6% and 85.0%, respectively, similar to the waterworks with the DBACF process. The UBACF greatly enhanced oxygen supply capability and mass transfer rate via aeration, and the NH3-N removal ability was significantly improved from 1.5 mg/L to more than 3 mg/L. Influent to the UBACF with higher turbidity could be coped with through the primary filtration of the ceramisite layer combined with fluid-bed technology, which gave the carbon bed a low-turbidity environment of less than 1.0 NTU. The backwashing parameters and carbon abrasion rate of the two processes were almost the same.

  18. Exposure to space radiation of high-performance infrared multilayer filters and materials technology experiments (A0056) (United States)

    Seeley, J. S.; Hunneman, R.; Whatley, A.; Lipscombe, D. R.


    Infrared multilayer interface filter which were used in satellite radiometers were examined. The ability of the filters to withstand the space environment in these applications is critical. An experiment on the LDEF subjects the filters to authoritative spectral measurements following space exposure to ascertain their suitability for spacecraft use and to permit an understanding of degradation mechanisms. The understanding of the effects of prolonged space exposure on spacecraft materials, surface finishes, and adhesive systems is important to the spacecraft designer. Materials technology experiments and experiment on infrared multilayer filters are discussed.

  19. Nanowires and sidewall Bragg gratings in silicon as enabling technologies for microwave photonic filters. (United States)

    Chen, Lawrence R; Li, Jia; Spasojevic, Mina; Adams, Rhys


    We describe the use of various silicon photonic device technologies to implement microwave photonic filters (MPFs). We demonstrate four-wave mixing in a silicon nanowire waveguide (SNW) to increase the number of taps for MPFs based on finite impulse response filter designs. Using a 12 mm long SNW reduces the footprint by five orders of magnitude compared to silica highly nonlinear fiber while only requiring approximately two times more input power. We also demonstrate optical delays based on serial sidewall Bragg grating arrays and step-chirped sidewall Bragg gratings in silicon waveguides. We obtain up to 63 ps delay in discrete steps from 15 ps to 32 ps over a wide bandwidth range from 33 nm to at least 62 nm. These components can be integrated with other silicon-based components such as integrated spectral shapers and modulators to realize a fully integrated MPF.

  20. Water Filters (United States)


    The Aquaspace H2OME Guardian Water Filter, available through Western Water International, Inc., reduces lead in water supplies. The filter is mounted on the faucet and the filter cartridge is placed in the "dead space" between sink and wall. This filter is one of several new filtration devices using the Aquaspace compound filter media, which combines company developed and NASA technology. Aquaspace filters are used in industrial, commercial, residential, and recreational environments as well as by developing nations where water is highly contaminated.


    The U.S. EPA has created the Environmental Technology Verification program to facilitate the deployment of innovative or improved environmental technologies through performance verification and dissemination of information. The program tested the performance of baghouse filtrati...

  2. Further development of the cleanable steel HEPA filter, cost/benefit analysis, and comparison with competing technologies

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, W.; Larsen, G.; Lopez, R.; Wilson, K.; Witherell, C.; McGregor, M.


    We have made further progress in developing a cleanable steel fiber HEPA filter. We fabricated a pleated cylindrical cartridge using commercially available steel fiber media that is made with 1 {mu}m stainless steel fibers and sintered into a sheet form. Test results at the Department of Energy (DOE) Filter Test Station at Oak Ridge show the prototype filter cartridge has 99.99% efficiency for 0.3 {mu}m dioctyl phthalate (DOP) aerosols and a pressure drop of 1.5 inches. Filter loading and cleaning tests using AC Fine dust showed the filter could be repeatedly cleaned using reverse air pulses. Our analysis of commercially optimized filters suggest that cleanable steel HEPA filters need to be made from steel fibers less than 1 {mu}m, and preferably 0.5 {mu}m, to meet the standard HEPA filter requirements in production units. We have demonstrated that 0.5 {mu}m steel fibers can be produced using the fiber bundling and drawing process. The 0.5 {mu}m steel fibers are then sintered into small filter samples and tested for efficiency and pressure drop. Test results on the sample showed a penetration of 0.0015% at 0.3 {mu}m and a pressure drop of 1.15 inches at 6.9 ft/min (3.5 cm/s) velocity. Based on these results, steel fiber media can easily meet the requirements of 0.03% penetration and 1.0 inch of pressure drop by using less fibers in the media. A cost analysis of the cleanable steel HEPA filter shows that, although the steel HEPA filter costs much more than the standard glass fiber HEPA filter, it has the potential to be very cost effective because of the high disposal costs of contaminated HEPA filters. We estimate that the steel HEPA filter will save an average of $16,000 over its 30 year life. The additional savings from the clean-up costs resulting from ruptured glass HEPA filters during accidents was not included but makes the steel HEPA filter even more cost effective. We also present the results of our evaluation of competing technologies with metallic and

  3. Metal-Mesh Optical Filter Technology for Mid IR, Far IR, and Submillimeter Project (United States)

    National Aeronautics and Space Administration — This SBIR Phase I proposal describes a method of fabrication of far IR and THZ range multilayer metal-mesh filters. This type of filter consists of alternative...

  4. Miniaturized and Ferrite Based Tunable Bandpass Filters in LCP and LTCC Technologies for SoP Applications

    KAUST Repository

    Arabi, Eyad A.


    Wireless systems with emerging applications are leaning towards small size, light-weight and low cost. Another trend for these wireless devices is that new applications and functionalities are being added without increasing the size of the device. To accomplish this, individual components must be miniaturized and the system should be designed to maximize the integration of the individual components. The high level of 3D integration feasible in system on package design (SoP) concept can fulfill the latter requirement. Bandpass filters are important components on all wireless systems to reject the unwanted signals and reduce interference. Being mostly implemented with passive and distributed components, bandpass filters take considerable space in a wireless system. Moreover, with emerging bands and multiple applications encompassed in a single device, many bandpass filters are required. The miniaturization related to bandpass filters can be approached by three main ways: (1) at the component level through the miniaturization of individual bandpass filters, (2) at the system level through the use of tunable filters to reduce the overall number of filters, and (3) at the system level through the high level of integration in a 3D SoP platform. In this work we have focused on all three aspects of miniaturization of band pass filters mentioned above. In the first part of this work, a low frequency (1.5 GHz global positioning system (GPS) band) filter implemented through 3D lumped components in two leading SoP technologies, namely low temperature co-fired ceramic (LTCC) and the liquid crystal polymers (LCP) is demonstrated. The miniaturized filter is based on a second order topology, which has been modified to improve the selectivity and out-of-band rejection without increasing the size. Moreover, for the case of LCP, the filter is realized in an ultra-thin stack up comprising four metallization layers with an overall thickness of only 100 _m. Due to its ultra


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) Verification Center. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of the size for particles equal to or smaller than...


    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) Verification Center. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of the size of those particles equal to and smalle...


    EPA's National Risk Management Research Laboratory, through its Environmental Technology Verification Program, evaluated the performance of a bag house filtration product for use controlling PM2.5. The product was BWF America, Inc., filter fabric Grade 700 Polyester Felt. All tes...

  8. Coarse Alignment Technology on Moving base for SINS Based on the Improved Quaternion Filter Algorithm. (United States)

    Zhang, Tao; Zhu, Yongyun; Zhou, Feng; Yan, Yaxiong; Tong, Jinwu


    Initial alignment of the strapdown inertial navigation system (SINS) is intended to determine the initial attitude matrix in a short time with certain accuracy. The alignment accuracy of the quaternion filter algorithm is remarkable, but the convergence rate is slow. To solve this problem, this paper proposes an improved quaternion filter algorithm for faster initial alignment based on the error model of the quaternion filter algorithm. The improved quaternion filter algorithm constructs the K matrix based on the principle of optimal quaternion algorithm, and rebuilds the measurement model by containing acceleration and velocity errors to make the convergence rate faster. A doppler velocity log (DVL) provides the reference velocity for the improved quaternion filter alignment algorithm. In order to demonstrate the performance of the improved quaternion filter algorithm in the field, a turntable experiment and a vehicle test are carried out. The results of the experiments show that the convergence rate of the proposed improved quaternion filter is faster than that of the tradition quaternion filter algorithm. In addition, the improved quaternion filter algorithm also demonstrates advantages in terms of correctness, effectiveness, and practicability.

  9. Coronary Artery Bypass Surgery (United States)

    ... don't help, you may need coronary artery bypass surgery. The surgery creates a new path for ... narrowed area or blockage. This allows blood to bypass (get around) the blockage. Sometimes people need more ...

  10. Heart bypass surgery - slideshow (United States)

    ... page: // Heart bypass surgery - series—Normal anatomy To use the sharing ... Editorial team. Related MedlinePlus Health Topics Coronary Artery Bypass Surgery A.D.A.M., Inc. is accredited ...

  11. Coronary Artery Bypass (United States)

    ... to 3 days in the Intensive Care Unit (ICU). Life After Bypass After bypass surgery, your doctor will recommend that you join a cardiac rehabilitation program. These programs help you make lifestyle changes ...

  12. Review of the state-of-the-art of exhaust particulate filter technology in internal combustion engines. (United States)

    Guan, Bin; Zhan, Reggie; Lin, He; Huang, Zhen


    The increasingly stringent emission regulations, such as US 2010, Tier 2 Bin 5 and beyond, off-road Tier 4 final, and Euro V/5 for particulate matter (PM) reduction applications, will mandate the use of the diesel particulate filters (DPFs) technology, which is proven to be the only way that can effectively control the particulate emissions. This paper covers a comprehensive overview of the state-of-the-art DPF technologies, including the advanced filter substrate materials, the novel catalyst formulations, the highly sophisticated regeneration control strategies, the DPF uncontrolled regenerations and their control methodologies, the DPF soot loading prediction, and the soot sensor for the PM on-board diagnostics (OBD) legislations. Furthermore, the progress of the highly optimized hybrid approaches, which involves the integration of diesel oxidation catalyst (DOC) + (DPF, NOx reduction catalyst), the selective catalytic reduction (SCR) catalyst coated on DPF, as well as DPF in the high-pressure exhaust gas recirculation (EGR) loop systems, is well discussed. Besides, the impacts of the quality of fuel and lubricant on the DPF performance and the maintenance and retrofit of DPF are fully elaborated. Meanwhile, the high efficiency gasoline particulate filter (GPF) technology is being required to effectively reduce the PM and particulate number (PN) emissions from the gasoline direct injection (GDI) engines to comply with the future increasingly stricter emissions regulations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. The research of full automatic oil filtering control technology of high voltage insulating oil (United States)

    Gong, Gangjun; Zhang, Tong; Yan, Guozeng; Zhang, Han; Chen, Zhimin; Su, Chang


    In this paper, the design scheme of automatic oil filter control system for transformer oil in UHV substation is summarized. The scheme specifically includes the typical double tank filter connection control method of the transformer oil of the UHV substation, which distinguishes the single port and the double port connection structure of the oil tank. Finally, the design scheme of the temperature sensor and respirator is given in detail, and the detailed evaluation and application scenarios are given for reference.

  14. Photographic filters (United States)

    Rodigues, Jose Eduardo; Santosdealmeida, Wagner


    Some of the main aspects related to photographic filters are examined and prepared as a reference for researchers and students of remote sensing. A large range of information about the filters including their basic fundamentals, classification, and main types is presented. The theme cannot be exhausted in this or any other individual publication because of its great complexity, profound theoretical publication, and dynmaic technological development. The subject does not deal only with filter applications in remote sensing. As much as possible, additional information about the utilization of these products in other professional areas, as pictorial photography, photographic processing, and optical engineering, were included.

  15. A 3-D miniaturized high selectivity bandpass filter in LTCC technology

    KAUST Repository

    Arabi, Eyad A.


    Transmission zeros are used to improve the roll-off factors of filters but as a consequence, the out-of-band rejection decreases. In this work, an LTCC filter design is presented which employs a series inductor (implemented as a via hole) to improve the out-of-band rejection by introducing a third transmission zero. The filter, designed for GPS band (1.57 GHz), has one of the smallest reported foot prints ((0.063×0.048×0.005)λg) and demonstrates the highest roll off factor (16.7 dB/100 MHz) for this band. With only four LTCC layers, the design is cost effective and thus highly suitable for miniaturized, ultra-thin system-on-package applications. © 2001-2012 IEEE.

  16. Evidence-Based Used, Yet Still Controversial: The Arterial Filter (United States)

    Somer, Filip De


    Abstract: Arterial line filters are considered by many as an essential safety measure inside a cardiopulmonary bypass circuit. There is no doubt that this was true during the bubble oxygenator era, but we can question whether the existing arterial line filter design and positioning of the filter are still optimal seeing the tremendous progress in cardiopulmonary bypass circuit components. This overview gives a critical overview of existing arterial line filter design. PMID:22730869

  17. A low-light-level video recursive filtering technology based on the three-dimensional coefficients (United States)

    Fu, Rongguo; Feng, Shu; Shen, Tianyu; Luo, Hao; Wei, Yifang; Yang, Qi


    Low light level video is an important method of observation under low illumination condition, but the SNR of low light level video is low, the effect of observation is poor, so the noise reduction processing must be carried out. Low light level video noise mainly includes Gauss noise, Poisson noise, impulse noise, fixed pattern noise and dark current noise. In order to remove the noise in low-light-level video effectively, improve the quality of low-light-level video. This paper presents an improved time domain recursive filtering algorithm with three dimensional filtering coefficients. This algorithm makes use of the correlation between the temporal domain of the video sequence. In the video sequences, the proposed algorithm adaptively adjusts the local window filtering coefficients in space and time by motion estimation techniques, for the different pixel points of the same frame of the image, the different weighted coefficients are used. It can reduce the image tail, and ensure the noise reduction effect well. Before the noise reduction, a pretreatment based on boxfilter is used to reduce the complexity of the algorithm and improve the speed of the it. In order to enhance the visual effect of low-light-level video, an image enhancement algorithm based on guided image filter is used to enhance the edge of the video details. The results of experiment show that the hybrid algorithm can remove the noise of the low-light-level video effectively, enhance the edge feature and heighten the visual effects of video.

  18. Failing arsenic mitigation technology in rural Bangladesh: explaining stagnation in niche formation of the Sono filter

    NARCIS (Netherlands)

    Kundu, D.K.; Mol, A.P.J.; Gupta, A.


    Arsenic contamination of shallow hand pump tube well drinking water in Bangladesh has created opportunities for radical innovations to emerge. One such innovation is the household Sono filter, designed to remove arsenic from water supplies. Applying a strategic niche management approach, and based

  19. Aspect-Oriented Programming Using Composition Filters, in Object-Oriented Technology

    NARCIS (Netherlands)

    Aksit, Mehmet; Demeyer, S.; Bosch, H.G.P.; Tekinerdogan, B.

    Software engineers may experience problems in modeling certain aspects while applying object-oriented techniques [4, 10, 11]. Composition-Filters are capable of expressing various different kinds of aspects in a uniform manner. These aspects are, for example, inheritance and delegation [1] and

  20. The Society of Thoracic Surgeons, The Society of Cardiovascular Anesthesiologists, and The American Society of ExtraCorporeal Technology: Clinical Practice Guidelines-Anticoagulation During Cardiopulmonary Bypass. (United States)

    Shore-Lesserson, Linda; Baker, Robert A; Ferraris, Victor A; Greilich, Philip E; Fitzgerald, David; Roman, Philip; Hammon, John W


    Despite more than a half century of "safe" cardiopulmonary bypass (CPB), the evidence base surrounding the conduct of anticoagulation therapy for CPB has not been organized into a succinct guideline. For this and other reasons, there is enormous practice variability relating to the use and dosing of heparin, monitoring heparin anticoagulation, reversal of anticoagulation, and the use of alternative anticoagulants. To address this and other gaps, The Society of Thoracic Surgeons, the Society of Cardiovascular Anesthesiologists, and the American Society of Extracorporeal Technology developed an Evidence Based Workgroup. This was a group of interdisciplinary professionals gathered to summarize the evidence and create practice recommendations for various aspects of CPB. To date, anticoagulation practices in CPB have not been standardized in accordance with the evidence base. This clinical practice guideline was written with the intent to fill the evidence gap and to establish best practices in anticoagulation therapy for CPB using the available evidence. To identify relevant evidence, a systematic review was outlined and literature searches were conducted in PubMed using standardized medical subject heading (MeSH) terms from the National Library of Medicine list of search terms. Search dates were inclusive of January 2000 to December 2015. The search yielded 833 abstracts, which were reviewed by two independent reviewers. Once accepted into the full manuscript review stage, two members of the writing group evaluated each of 286 full papers for inclusion eligibility into the guideline document. Ninety-six manuscripts were included in the final review. In addition, 17 manuscripts published before 2000 were included to provide method, context, or additional supporting evidence for the recommendations as these papers were considered sentinel publications. Members of the writing group wrote and developed recommendations based on review of the articles obtained and achieved

  1. Environmental Technology Verification: Baghouse Filtration Products--TDC Filter Manufacturing, Inc., SB025 Filtration Media (United States)

    The U.S. Environmental Protection Agency (EPA) has created the Environmental Technology Verification (ETV) Program to facilitate the deployment of innovative or improved environmental technologies through performance verification and dissemination of information. ETV seeks to ach...

  2. 3-5{mu}m F-P Tunable Filter Array based on MEMS technology

    Energy Technology Data Exchange (ETDEWEB)

    Xu Wei; Chen Sihai; Bao Shiwei; Zhou Yifan; Zhao Sangzhi; Luo Huan [College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Meng Qinghua, E-mail: [Guangxi Normal University, Guilin541002 (China)


    In this paper the design, fabrication and test of a MEMS F-P filter operating in 3-5{mu}m range is presented. The initial design of micro-bridge structure was achieved through COMSOL simulation software. In the simulation, the micro-bridge could achieve a displacement of 0.6{mu}m under very low applied voltage of 30V, while still preserving good mirror parallelism. By using surface micromachining techniques, a 200 x 200 array of F-P tunable micro-bridge was fabricated. SEM photographs of the fabricated device and method of optical performance test are also introduced. This MEMS F-P tunable filter can be a potential application in spectroscopic sensing and optical communication system.

  3. Bypass materials in vascular surgery

    Directory of Open Access Journals (Sweden)

    Willich, Stephan N.


    (DIMDI, as well as by a manual search. The for-mer included the following electronic resources: SOMED (SM78, Cochrane Library - Central (CCTR93, MEDLINE Alert (ME0A, MEDLINE (ME95, CATFILEplus (CATLINE (CA66, ETHMED (ED93, GeroLit (GE79, HECLINET (HN69, AMED (CB85, CAB Abstracts (CV72, GLOBAL Health (AZ72, IPA (IA70, El-sevier BIOBASE (EB94, BIOSIS Previews (BA93, EMBASE (EM95, EMBASE Alert (EA08, SciSearch (IS90, Cochrane Library - CDSR (CDSR93, NHS-CRD-DARE (CDAR94, NHS-CRD-HTA (INAHTA, and NHS-EED (NHSEED. The present report included German and English literature published between the years 1999 and 2004. A list of the search parameters can be found in the appendix. No limits were placed on the target population, and the methodical quality of the included studies was determined using standardised checklists. Results: The studies included in this health technology assessment compared the following bypass materials: autologous vein, human umbilical vein (HUV and synthetic materials such as PTFE or Dacron®. Both the systematic reviews and the randomised controlled trials comparing autologous vein grafts to other bypass materials come to the conclusion that autologous vein is superior to all other materials. From a medical viewpoint, there are no clear differences between the various synthetic materials.To date, the subject of bypass materials in vascular surgery has not been addressed comprehensively from an economic point of view. Indeed, we were able to identify only one publication that compared the cost of various bypass materials. The remaining health economic studies did not compare costs, cost effectiveness, or quality of life associated with the use of various bypass materials. Discussion: When deciding which bypass material to use, vascular surgeons take a number of medical considerations into account, including the bypass area, the availability of autologous vein, the amount of operation time available, and the health status of the patient. The studies

  4. The Society of Thoracic Surgeons, The Society of Cardiovascular Anesthesiologists, and The American Society of ExtraCorporeal Technology: Clinical Practice Guidelines-Anticoagulation During Cardiopulmonary Bypass. (United States)

    Shore-Lesserson, Linda; Baker, Robert A; Ferraris, Victor A; Greilich, Philip E; Fitzgerald, David; Roman, Philip; Hammon, John W


    Despite more than a half century of "safe" cardiopulmonary bypass (CPB), the evidence base surrounding the conduct of anticoagulation therapy for CPB has not been organized into a succinct guideline. For this and other reasons, there is enormous practice variability relating to the use and dosing of heparin, monitoring heparin anticoagulation, reversal of anticoagulation, and the use of alternative anticoagulants. To address this and other gaps, The Society of Thoracic Surgeons, the Society of Cardiovascular Anesthesiologists, and the American Society of Extracorporeal Technology developed an Evidence Based Workgroup. This was a group of interdisciplinary professionals gathered to summarize the evidence and create practice recommendations for various aspects of CPB. To date, anticoagulation practices in CPB have not been standardized in accordance with the evidence base. This clinical practice guideline was written with the intent to fill the evidence gap and to establish best practices in anticoagulation therapy for CPB using the available evidence. To identify relevant evidence, a systematic review was outlined and literature searches were conducted in PubMed using standardized medical subject heading (MeSH) terms from the National Library of Medicine list of search terms. Search dates were inclusive of January 2000 to December 2015. The search yielded 833 abstracts, which were reviewed by two independent reviewers. Once accepted into the full manuscript review stage, two members of the writing group evaluated each of 286 full papers for inclusion eligibility into the guideline document. Ninety-six manuscripts were included in the final review. In addition, 17 manuscripts published before 2000 were included to provide method, context, or additional supporting evidence for the recommendations as these papers were considered sentinel publications. Members of the writing group wrote and developed recommendations based on review of the articles obtained and achieved

  5. The Evolution of Improved Baghouse Filter Media as Observed in the Environmental Technology Verification Program (United States)

    The U.S. EPA implemented the Environmental Technology Verification (ETV) program in 1995 to generate independent and credible data on the performance of innovative technologies that have the potential to improve protection of public health and the environment. Results are publicl...

  6. The Society of Thoracic Surgeons, The Society of Cardiovascular Anesthesiologists, and The American Society of ExtraCorporeal Technology: Clinical Practice Guidelines for Cardiopulmonary Bypass—Temperature Management during Cardiopulmonary Bypass (United States)

    Engelman, Richard; Baker, Robert A.; Likosky, Donald S.; Grigore, Alina; Dickinson, Timothy A.; Shore-Lesserson, Linda; Hammon, John W.


    Abstract: To improve our understanding of the evidence-based literature supporting temperature management during adult cardiopulmonary bypass, The Society of Thoracic Surgeons, the Society of Cardiovascular Anesthesiology and the American Society of ExtraCorporeal Technology tasked the authors to conduct a review of the peer-reviewed literature, including 1) optimal site for temperature monitoring, 2) avoidance of hyperthermia, 3) peak cooling temperature gradient and cooling rate, and 4) peak warming temperature gradient and rewarming rate. Authors adopted the American College of Cardiology/American Heart Association method for development clinical practice guidelines, and arrived at the following recommendation. PMID:26543248

  7. Arterial bypass leg - slideshow (United States)

    ... presentations/100155.htm Arterial bypass leg - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  8. Thrombin During Cardiopulmonary Bypass

    National Research Council Canada - National Science Library

    Edmunds, L. Henry; Colman, Robert W


    Cardiopulmonary bypass (CPB) ignites a massive defense reaction that stimulates all blood cells and five plasma protein systems to produce a myriad of vasoactive and cytotoxic substances, cell-signaling molecules...

  9. Cardiopulmonary bypass in pregnancy

    National Research Council Canada - National Science Library

    Kapoor, MukulChandra


      Cardiac surgery carried out on cardiopulmonary bypass (CPB) in a pregnant woman is associated with poor neonatal outcomes although maternal outcomes are similar to cardiac surgery in non-pregnant women...

  10. Cardiopulmonary bypass and hemostasis

    NARCIS (Netherlands)

    Eijsman, Leon


    In chapter 1, we recalled that intracardiac defects can only be corrected when cardiopulmonary circulation is maintained by extracorporeal criculation and ventilation. To prevent clot formation in this artificial circuit, the socalled cardiopulmonary bypass (CPB), we completely depend on the

  11. Gastric bypass surgery - discharge (United States)

    ... heart disease Gastric bypass surgery Laparoscopic gastric banding Obesity Obstructive sleep apnea - adults Type 2 diabetes Patient Instructions Getting out of bed after surgery Weight-loss surgery - after - what to ask your doctor Weight- ...

  12. Clarification of vaccines: An overview of filter based technology trends and best practices. (United States)

    Besnard, Lise; Fabre, Virginie; Fettig, Michael; Gousseinov, Elina; Kawakami, Yasuhiro; Laroudie, Nicolas; Scanlan, Claire; Pattnaik, Priyabrata


    Vaccines are derived from a variety of sources including tissue extracts, bacterial cells, virus particles, recombinant mammalian, yeast and insect cell produced proteins and nucleic acids. The most common method of vaccine production is based on an initial fermentation process followed by purification. Production of vaccines is a complex process involving many different steps and processes. Selection of the appropriate purification method is critical to achieving desired purity of the final product. Clarification of vaccines is a critical step that strongly impacts product recovery and subsequent downstream purification. There are several technologies that can be applied for vaccine clarification. Selection of a harvesting method and equipment depends on the type of cells, product being harvested, and properties of the process fluids. These techniques include membrane filtration (microfiltration, tangential-flow filtration), centrifugation, and depth filtration (normal flow filtration). Historically vaccine harvest clarification was usually achieved by centrifugation followed by depth filtration. Recently membrane based technologies have gained prominence in vaccine clarification. The increasing use of single-use technologies in upstream processes necessitated a shift in harvest strategies. This review offers a comprehensive view on different membrane based technologies and their application in vaccine clarification, outlines the challenges involved and presents the current state of best practices in the clarification of vaccines. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Research on the shortwave infrared hyperspectral imaging technology based on Integrated Stepwise filter (United States)

    Wei, Liqing; Xiao, Xizhong; Wang, Yueming; Zhuang, Xiaoqiong; Wang, Jianyu


    Space-borne hyperspectral imagery is an important tool for earth sciences and industrial applications. Higher spatial and spectral resolutions have been sought persistently, although this results in more power, larger volume and weight during a space-borne spectral imager design. For miniaturization of hyperspectral imager and optimization of spectral splitting methods, several methods are compared in this paper. Spectral time delay integration (TDI) method with high transmittance Integrated Stepwise Filter (ISF) is proposed.With the method, an ISF imaging spectrometer with TDI could achieve higher system sensitivity than the traditional prism/grating imaging spectrometer. In addition, the ISF imaging spectrometer performs well in suppressing infrared background radiation produced by instrument. A compact shortwave infrared (SWIR) hyperspectral imager prototype based on HgCdTe covering the spectral range of 2.0-2.5 μm with 6 TDI stages was designed and integrated. To investigate the performance of ISF spectrometer, a method to derive the optimal blocking band curve of the ISF is introduced, along with known error characteristics. To assess spectral performance of the ISF system, a new spectral calibration based on blackbody radiation with temperature scanning is proposed. The results of the imaging experiment showed the merits of ISF. ISF has great application prospects in the field of high sensitivity and high resolution space-borne hyperspectral imagery.

  14. Bypassing damaged nervous tissue

    CERN Document Server

    Shneider, M N


    We show the principal ability of bypassing damaged demyelinated portions of nervous tissue, thereby restoring its normal function for the passage of action potentials. We carry out a theoretical analysis on the basis of the synchronization mechanism of action potential propagation along a bundle of neurons, proposed recently in [1]. And we discuss the feasibility of implement a bypass to restore damaged nervous tissue and creating an artificial neuron network.

  15. Multiphase clock generators with controlled clock impulse width for programmable high order rotator SC FIR filters realized in 0.35 μm CMOS technology (United States)

    Dlugosz, Rafal; Pawlowski, Pawel; Dabrowski, Adam


    Complexity of clock generator is one of the most important parameters in the design and optimization of switched-capacitor (SC) finite impulse response (FIR) filters. There are different SC FIR filter architectures. Some of them need a simple clock generator but the others require a quite complicated multiphase clock system. In the latter case an external clock system (i.e., outside the integrated circuit) is unrealistic because of a great number of the required external pins. We have implemented various SC FIR filter architectures together with complex internal clock generators in the CMOS 0.8 μm and 0.35 μm technologies. One of the most important problems in the design process was the optimization of waveforms and widths of the clock impulses. SC FIR filters are very sensitive to parameters of clock systems. Thus the clock generators must be designed very precisely. We demonstrate results of the design of the 64-phase clock generator for a programmable rotator SC FIR filter. In our approach the width of the clock impulses is controlled by two external signals. This is a very convenient solution, because optimization of the clock impulses, which was difficult in other approaches, is currently much easier. The internal clock generator area is ca. 0.15 mm2 in the CMOS 0.35 μm technology, i.e., only 7 % of the entire SC FIR filter chip area.

  16. Exposure to space radiation of high-performance infrared multilayer filters and materials technology experiment (A0056) (United States)

    Hawkins, Gary J.; Seeley, John S.; Hunneman, Roger


    Infrared optical multilayer filters and materials were exposed to the space environment of low Earth orbit on LDEF. The effects are summarized of that environment on the physical and optical properties of the filters and materials flown.

  17. Novel Backup Filter Device for Candle Filters

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, B.; Goldsmith, R.; Dunham, G.; Henderson, A.


    bypassing a broken or leaking candle while having a low enough pressure drop to allow the candle to be backpulse-regenerated. Forward-flow pressure drop should increase by no more than 20% because of incorporation of the fail-safe filter.

  18. Institute for Clean Energy Technology Mississippi State University NSR&D Aged HEPA Filter Study Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Jacks, Robert [Mississippi State Univ., Mississippi State, MS (United States); Stormo, Julie [Mississippi State Univ., Mississippi State, MS (United States); Rose, Coralie [Mississippi State Univ., Mississippi State, MS (United States); Rickert, Jaime [Mississippi State Univ., Mississippi State, MS (United States); Waggoner, Charles A. [Mississippi State Univ., Mississippi State, MS (United States)


    Data have demonstrated that filter media lose tensile strength and the ability to resist the effects of moisture as a function of age. Testing of new and aged filters needs to be conducted to correlate reduction of physical strength of HEPA media to the ability of filters to withstand upset conditions. Appendix C of the Nuclear Air Cleaning Handbook provides the basis for DOE’s HEPA filter service life guidance. However, this appendix also points out the variability of data, and it does not correlate performance of aged filters to degradation of media due to age. Funding awarded by NSR&D to initiate full-scale testing of aged HEPA filters addresses the issue of correlating media degradation due to age with testing of new and aged HEPA filters under a generic design basis event set of conditions. This funding has accelerated the process of describing this study via: (1) establishment of a Technical Working Group of all stakeholders, (2) development and approval of a test plan, (3) development of testing and autopsy procedures, (4) acquiring an initial set of aged filters, (5) testing the initial set of aged filters, and (6) developing the filter test report content for each filter tested. This funding was very timely and has moved the project forward by at least three years. Activities have been correlated with testing conducted under DOE-EM funding for evaluating performance envelopes for AG-1 Section FC Separator and Separatorless filters. This coordination allows correlation of results from the NSR&D Aged Filter Study with results from testing new filters of the Separator and Separatorless Filter Study. DOE-EM efforts have identified approximately 100 more filters of various ages that have been stored under Level B conditions. NSR&D funded work allows a time for rigorous review among subject matter experts before moving forward with development of the testing matrix that will be used for additional filters. The NSR&D data sets are extremely valuable in as much

  19. The experience of totally endoscopic coronary bypass grafting with the robotic system «Da Vinci» in Russia (United States)

    Efendiev, V. U.; Alsov, S. A.; Ruzmatov, T. M.; Mikheenko, I. L.; Chernyavsky, A. M.; Malakhov, E. S.


    A new technology - a thoracoscopic coronary bypass grafting with the use of Da Vinci robotic system in Russia is represented by the experience of NRICP. The technology was introduced in Russia in 2011. Overall, one hundred endoscopic coronary artery bypass procedures were performed. We have compared and analyzed results of coronary artery stenting vs minimally invasive coronary artery bypass grafting. According to the results, totally endoscopic coronary artery bypass grafting has several advantages over alternative treatment strategies.

  20. HEPA filter monitoring program (United States)

    Kirchner, K. N.; Johnson, C. M.; Aiken, W. F.; Lucerna, J. J.; Barnett, R. L.; Jensen, R. T.


    The testing and replacement of HEPA filters, widely used in the nuclear industry to purify process air, are costly and labor-intensive. Current methods of testing filter performance, such as differential pressure measurement and scanning air monitoring, allow determination of overall filter performance but preclude detection of incipient filter failure such as small holes in the filters. Using current technology, a continual in-situ monitoring system was designed which provides three major improvements over current methods of filter testing and replacement. The improvements include: cost savings by reducing the number of intact filters which are currently being replaced unnecessarily; more accurate and quantitative measurement of filter performance; and reduced personnel exposure to a radioactive environment by automatically performing most testing operations.

  1. Rural Bypass for Elective Surgeries. (United States)

    Weigel, Paula A M; Ullrich, Fred; Finegan, Chance N; Ward, Marcia M


    Rural bypass of Critical Access Hospitals (CAHs) for elective inpatient and outpatient surgical procedures has not been studied. Residents choosing to have their elective surgeries elsewhere, when the local CAH provides those surgical services, erode their rural hospital's financial base. The purpose of this research is to describe the elective surgical bypass rate, the procedures most commonly bypassed by rural residents, the distribution of volume among CAHs that offer elective surgical services, and factors predictive of bypass. A sample of elective surgery discharges was created from the 2011 Healthcare Cost and Utilization Project State Inpatient Databases and State Ambulatory Surgery Databases for Colorado, North Carolina, Vermont, and Wisconsin. Frequencies of procedures bypassed and CAH volume distribution were performed. Logistic regression was used to model factors associated with rural bypass for elective surgical care. The rural bypass rate for elective surgical procedures is 48.4%. Procedures bypassed most are operations on the musculoskeletal system, eye, and digestive system. Annual volume distribution for elective surgical procedures among CAHs varied widely. Patients who are younger, medically complex, at higher surgical risk, and have private insurance are at higher odds of bypass. Patients are also more likely to bypass low-volume hospitals. Rural hospitals should consider developing surgical services that are performed electively and on an outpatient basis that are attractive to a broader rural population. CAHs that already offer elective surgical procedures and yet who are still bypassed must examine the mutable factors that drive bypass behavior. © 2015 National Rural Health Association.

  2. The Best Bypass Surgery Trial

    DEFF Research Database (Denmark)

    Møller, Christian H; Jensen, Birte Østergaard; Gluud, Christian


    Recent trials suggest that off-pump coronary artery bypass grafting (OPCAB) reduces the risk of mortality and morbidity compared with conventional coronary artery bypass grafting (CCAB) using cardiopulmonary bypass. Patients with a moderate- to high-risk of complications after CCAB may have...

  3. Precipitation-filtering technology for uranium waste solution generated on washing-electrokinetic decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gye-Nam, E-mail:; Park, Uk-Ryang; Kim, Seung-Soo; Moon, Jei-Kwon


    Graphical abstract: A recycling process diagram for the volume reduction of waste solution generated from washing-electrokinetic decontamination. - Highlights: • A process for recycling a waste solution generated was developed. • The total metal precipitation rate by NaOH in a supernatant after precipitation was the highest at pH 9. • The uranium radioactivity in the treated solution upon injection of 0.2 g of alum was lower. • After drying, the volume of sludge was reduced to 35% of the initial sludge volume. - Abstract: Large volumes of uranium waste solution are generated during the operation of washing-electrokinetic decontamination equipment used to remove uranium from radioactive soil. A treatment technology for uranium waste solution generated upon washing-electrokinetic decontamination for soil contaminated with uranium has been developed. The results of laboratory-size precipitation experiments were as follows. The total amount of metal precipitation by NaOH for waste solution was highest at pH 11. Ca(II), K(I), and Al(III) ions in the supernatant partially remained after precipitation, whereas the concentration of uranium in the supernatant was below 0.2 ppm. Also, when NaOH was used as a precipitant, the majority of the K(I) ions in the treated solution remained. The problem of CaO is to need a long dissolution time in the precipitation tank, while Ca(OH){sub 2} can save a dissolution time. However, the volume of the waste solution generated when using Ca(OH){sub 2} increased by 8 mL/100 mL (waste solution) compared to that generated when using CaO. NaOH precipitant required lower an injection volume lower than that required for Ca(OH){sub 2} or CaO. When CaO was used as a precipitant, the uranium radioactivity in the treated solution at pH 11 reached its lowest value, compared to values of uranium radioactivity at pH 9 and pH 5. Also, the uranium radioactivity in the treated solution upon injection of 0.2 g of alum with CaO or Ca(OH){sub 2} was

  4. Further development of the cleanable steel HEPA filter, cost/benefit analysis, and comparison with competing technologies

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, W.; Lopez, R.; Wilson, K. [Lawrence Livermore National Lab., CA (United States)] [and others


    We have made further progress in developing a cleanable steel fiber HEPA filter. We fabricated a pleated cylindrical cartridge using commercially available steel fiber media that is made with 1 {mu}m stainless steel fibers and sintered into a sheet form. Test results at the Department of Energy (DOE) Filter Test Station at Oak Ridge show the prototype filter cartridge has 99.99% efficiency for 0.3 {mu}m dioctyl phthalate (DOP) aerosols and a pressure drop of 1.5 inches. Filter loading and cleaning tests using AC Fine dust showed the filter could be repeatedly cleaned using reverse air pulses. Our analysis of commercially optimized filters suggest that cleanable steel HEPA filters need to be made from steel fibers less than 1{mu}m, and preferably 0.5 {mu}m, to meet the standard HEPA filter requirements in production units. We have demonstrated that 0.5 {mu}m steel fibers can be produced using the fiber bundling and drawing process. The 0.5 {mu}m steel fibers are then sintered into small filter samples and tested for efficiency and pressure drop. Test results on the sample showed a penetration of 0.0015 % at 0.3 {mu}m and a pressure drop of 1.15 inches at 6.9 ft/min (3.5 cm/s) velocity. Based on these results, steel fiber media can easily meet the requirements of 0.03 % penetration and 1.0 inch of pressure drop by using less fibers in the media. A cost analysis of the cleanable steel HEPA filter shows that, although the steel HEPA filter costs much more than the standard glass fiber HEPA filter, it has the potential to be very cost effective because of the high disposal costs of contaminated HEPA filters. We estimate that the steel HEPA filter will save an average of $16,000 over its 30 year life. The additional savings from the clean-up costs resulting from ruptured glass HEPA filters during accidents was not included but makes the steel HEPA filter even more cost effective. 33 refs., 28 figs., 1 tab.

  5. Design of Slow Sand Filter Technology for Rural Water Treatment in Girei, Adamawa State, North Eastern Nigeria


    B. A. Ankidawa; A. A. Tope


    Treatment of water has a great influence on the use of water for domestic use both in rural and urban areas. Slow sand filtration involves the use of beds of sand for the filtration of water. The reason for designing slow sand filter for rural water treatment is to make treatment of water easy and qualitative. This research involves the use of three tanks, filter beds, filter media and filtrate tanks. Raw water is filtered by the layers of different sand particles, and conveyed by pipe after ...

  6. Aortic valve bypass

    DEFF Research Database (Denmark)

    Lund, Jens T; Jensen, Maiken Brit; Arendrup, Henrik


    In aortic valve bypass (AVB) a valve-containing conduit is connecting the apex of the left ventricle to the descending aorta. Candidates are patients with symptomatic aortic valve stenosis rejected for conventional aortic valve replacement (AVR) or transcatheter aortic valve implantation (TAVI...

  7. Artery Bypass Grafting

    African Journals Online (AJOL)


    nary artery disease (CAD) was coronary artery bypass graft (CAB G) using a segment of saphenous vein interposed between the ascend- ing aorta and the coronary artery distal to the obstructing lesion. This was performed by David Sabiston of Duke University in 1962. With the use of the recently developed technique of ...

  8. Research on Discretization PI Control Technology of Single-Phase Grid-Connected Inverter with LCL Filter

    Directory of Open Access Journals (Sweden)

    Jianke Li


    Full Text Available Compared with L-type filter, LCL-type filter is more suitable for high-power low-switching frequency applications with reducing the inductance, improving dynamic performance. However, the parameter design for the LCL filter is more complex due to the influence of the controller response performance of the converter. If the harmonic current around switching frequency can be fully suppressed, it is possible for inverter to decrease the total inductance as well as the size and the cost. In this paper, the model of the LCL filter is analyzed and numerical algorithms are adopted to analyze the stability of the closed-loop control system and stable regions are deduced with different parameters of LCL filter. Then, the minimum sampling frequencies are deduced with different conditions. Simulation and experimental results are provided to validate the research on the generating mechanism for the unstable region of sampling frequency.

  9. Technological simulation of the process of filtering water for human consumption; Simulacion tecnologica del proceso de filtracion en aguas para el consumo humano

    Energy Technology Data Exchange (ETDEWEB)

    Marquez Canosa, E.; Herrera Vasconselo, T.; Marques, R.J.; Mondelo Rodriguez, A.; Tito Rigau, J.


    Theoretical bases of filtration process technological simulation through porous media state that physical fundamental of these phenomena does not change and acting torches change just in magnitude, but not in natural, inside a defined bound. In this paper is apply a methodology for determining theoretical parameters, which one are characteristics of separated particles intensity, adhesion intensity and particles penetration velocity inside packed bed. Parameters above mentioned were evaluate in fifteen sand filters and fifteen zeolite filters suing output water of coagulation-flocculation process of a potabilization plant, in a laboratory scale. Through technological simulation it was possible to make clear process filtration kinetic also to determine optimum operation and design parameters. (Author) 28 refs.

  10. Bypass: A Memoir


    Amato, Joseph A.


    This inquiry into matters of heart, conducted under the shadows of pending surgery, awakens themes of boyhood, education, and marriage and prompt questions about loyalty to a deceased father, connections with immigrant grandparents, loss and rediscovery of faith, and solitude versus community. A medical narrative, the book also chronicles a span of contemporary American life. Throughout Amato's account, the consistent reminder of his upcoming bypass invites readers to reflect on their own liv...

  11. Filtration of activated granulocytes during cardiopulmonary bypass surgery : A morphologic and immunologic study to characterize the trapped leukocytes

    NARCIS (Netherlands)

    Smit, JJJ; de Vries, AJ; Gu, YJ; van Oeveren, W

    Cardiopulmonary bypass surgery induces an inflammatory reaction among others by activation of granulocytes. Leukocyte filtration has been shown to reduce the postoperative morbidity mediated by activated granulocytes. However, little is known about the mechanism of filter-leukocyte interaction, This

  12. Relationship of femorodistal bypass patency to clinical outcome. Iloprost Bypass International Study Group

    DEFF Research Database (Denmark)

    Watson, H R; Schroeder, T V; Simms, M H


    To investigate the relationship between bypass patency, limb survival and clinical symptoms after femorodistal bypass procedures.......To investigate the relationship between bypass patency, limb survival and clinical symptoms after femorodistal bypass procedures....

  13. Nanofiber Filters Eliminate Contaminants (United States)


    With support from Phase I and II SBIR funding from Johnson Space Center, Argonide Corporation of Sanford, Florida tested and developed its proprietary nanofiber water filter media. Capable of removing more than 99.99 percent of dangerous particles like bacteria, viruses, and parasites, the media was incorporated into the company's commercial NanoCeram water filter, an inductee into the Space Foundation's Space Technology Hall of Fame. In addition to its drinking water filters, Argonide now produces large-scale nanofiber filters used as part of the reverse osmosis process for industrial water purification.

  14. The scientific evidence of arterial line filtration in cardiopulmonary bypass. (United States)

    Johagen, Daniel; Svenmarker, Staffan


    The indication for arterial line filtration (ALF) is to inhibit embolisation during cardiopulmonary bypass. Filtration methods have developed from depth filters to screen filters and from a stand-alone component to an integral part of the oxygenator. For many years, ALF has been a standard adopted by a majority of cardiac centres worldwide. The following review aims to summarize the available evidence in support for ALF and report on its current practice in Europe. The principles and application of ALF in Europe was investigated using a survey conducted in 2014. The scientific evidence for ALF was examined by performing a systematic literature search in six different databases, using the following search terms: "Cardiopulmonary bypass AND filters AND arterial". The primary endpoint was protection against cerebral injury verified by the degree of cerebral embolisation or cognitive tests. The secondary endpoint was improvement of the clinical outcome verified elsewise. Only randomised clinical trials were considered. The response rate was 31% (n=112). The great majority (88.5%) of respondents were using ALF, following more than 10 years of experience. Integrated arterial filtration was used by 55%. Of respondents not using ALF, fifty-four percent considered starting using integrated arterial filtration. The systematic literature database search returned 180 unique publications where 82 were specifically addressing ALF in cardiopulmonary bypass. Only four out of the 82 identified publications fulfilled our inclusion criteria. Of these, three were more than 20 years old and based on the use of bubble oxygenation. ALF is a standard implemented in a majority of cardiopulmonary bypass procedures in Europe. The level of scientific evidence available in support of current arterial line filtration methods in cardiopulmonary bypass is, however, poor. Large, well-designed, randomised trials are warranted. © The Author(s) 2015.

  15. Your diet after gastric bypass surgery (United States)

    Gastric bypass surgery - your diet; Obesity - diet after bypass; Weight loss - diet after bypass ... completely. Some of these are pasta, rice, bread, raw vegetables, and meats. Adding a low-fat sauce, ...

  16. Microwave Filters


    Zhou, Jiafeng


    The general theory of microwave filter design based on lumped-element circuit is described in this chapter. The lowpass prototype filters with Butterworth, Chebyshev and quasielliptic characteristics are synthesized, and the prototype filters are then transformed to bandpass filters by lowpass to bandpass frequency mapping. By using immitance inverters ( J - or K -inverters), the bandpass filters can be realized by the same type of resonators. One design example is given to verify the theory ...

  17. Coronary Artery Bypass

    Directory of Open Access Journals (Sweden)

    Kadri Ceberut


    Full Text Available Ancient schwannoma is a rare variant of neural tumors though rarely seen in the thorax. The combination with coronary artery diseases is also rare. Here we describe a 66 year-old male who had undergone one-stage combined surgery for thoracic ancient schwannomas removal and coronary artery disease. The masses were, respectively, 13 cm in the middle mediastinum and 5 cm in diameter originating from the intercostal nerve. The tumors were successfully removed using sternotomy, and then a coronary artery bypass grafting was performed. Here we discuss this rare tumor in relation to the relevant literature.

  18. Bionics: prcise color tuning by interference in nature and technology-applications in surface-micromachined 1.55μm vertical air-cavity filters (United States)

    Hillmer, Hartmut; Daleiden, Juergen; Prott, Cornelia; Irmer, Soeren; Roemer, Friedhard; Ataro, Edwin; Tarraf, Amer; Ruehling, H.; Maniak, Markus; Strassner, Martin


    Bionics transfers the principles of success of nature into natural science, engineering disciplines and applications. Often generation and detection of different spectral colors play key roles in communication in both, nature and technology. The latter one refers e.g. to dense wavelength division multiplex optical communication systems. This paper shows interesting parallels in tunable spectral light filtering by butterfly wings and by tunable optical filters used in optical communication systems. In both cases light interferes constructively and destructively with nano- and microstructures of appropriate shape, dimensions and materials. In this paper methodology is strongly emphasized. We demonstrate that tailored scaling allows the effectiveness of physical effects to be enhanced in nature and technology. These principles are rigorously applied in micromachined 1.55μm vertical-resonator-based filters, capable of wide, continuous, monotonic and kink-free tuning by a single control parameter. Tuning is achieved by mechanically actuating one or several membranes embedded by air-gaps in a vertical resonator including two ultra-highly reflective DBR mirrors. The layers of mirrors reveal a very strong refractive index contrast. Filters including InP/air-gap DBR's (3.5 periods) using GaInAs sacrificial layers reveal a continuous tuning of >9% of the absolute wavelength. Varying a reverse voltage (U=0 .. -3.2V) between the membranes, a tuning range up to 142nm was obtained due to electrostatic actuation. Appropriate miniaturization is shown to increase the mechanical stability and the effectiveness of spectral tuning by electrostatic actuation since the relative significance of the fundamental physical forces can be shifted considerably by appropriate scaling.

  19. Heart bypass surgery - minimally invasive - discharge (United States)

    Minimally invasive direct coronary artery bypass - discharge; MIDCAB - discharge; Robot assisted coronary artery bypass - discharge; RACAB - discharge; Keyhole heart surgery - discharge; Coronary artery disease - MIDCAB discharge; CAD - ...

  20. Spiritual Bypass: A Preliminary Investigation (United States)

    Cashwell, Craig S.; Glosoff, Harriet L.; Hammond, Cheree


    The phenomenon of spiritual bypass has received limited attention in the transpersonal psychology and counseling literature and has not been subjected to empirical inquiry. This study examines the phenomenon of spiritual bypass by considering how spirituality, mindfulness, alexithymia (emotional restrictiveness), and narcissism work together to…

  1. Construct exploit constraint in crash analysis by bypassing canary (United States)

    Huang, Ning; Huang, Shuguang; Huang, Hui; Chang, Chao


    Selective symbolic execution is a common program testing technology. Developed on the basis of it, some crash analysis systems are often used to test the fragility of the program by constructing exploit constraints, such as CRAX. From the study of crash analysis based on symbolic execution, this paper find that this technology cannot bypass the canary stack protection mechanisms. This paper makes the improvement uses the API hook in Linux. Experimental results show that the use of API hook can effectively solve the problem that crash analysis cannot bypass the canary protection.


    EPA‘s Environmental Technology Verification program is designed to further environmental protection by accelerating the acceptance and use of improved and cost effective technologies. This is done by providing high-quality, peer reviewed data on technology performance to those in...

  3. Monolithic integrated switched-capacitor filters. I (United States)

    Rienecker, W.


    The historical background of switched-capacitor filters is reviewed, and advanced design techniques for such filters are considered with reference to filter implementation in integrated systems. It is shown that basic equivalences between the components of time-invariant and time-variant networks make it possible to construct switched-capacitor filters that imitate classic filter types. Some examples of commercial switched-capacitor filters show the advantages of this technology.

  4. Water Filters (United States)


    A compact, lightweight electrolytic water filter generates silver ions in concentrations of 50 to 100 parts per billion in the water flow system. Silver ions serve as effective bactericide/deodorizers. Ray Ward requested and received from NASA a technical information package on the Shuttle filter, and used it as basis for his own initial development, a home use filter.

  5. Passage of downstream migrant American eels through an airlift-assisted deep bypass (United States)

    Haro, Alexander J.; Watten, Barnaby J.; Noreika, John


    Traditional downstream guidance and bypass facilities for anadromous fishes (i.e., surface bypasses, surface guidance structures, and behavioral barriers) have frequently been ineffective for anguillid eels. Because eels typically spend the majority of their time near the bottom in the vicinity of intake structures, deep bypass structures with entrances near the bottom hold promise for increased effectiveness, thereby aiding in the recovery of this important species. A new design of a deep bypass system that uses airlift technology (the Conte Airlift Bypass) to induce flow in a bypass pipe was tested in a simulated intake entrance environment under controlled laboratory conditions. Water velocities of 0.9–1.5 m s−1 could be generated at the bypass entrance (opening with 0.073 m2 area), with corresponding flows through the bypass pipe of 0.07–0.11 m3 s−1. Gas saturation and hydrostatic pressure within the bypass pipe did not vary appreciably from a control (no air) condition under tested airflows. Migratory silver-phase American eels (Anguilla rostrata) tested during dark conditions readily located, entered, and passed through the bypass; initial avoidance rates (eels approaching but not entering the bypass entrance) were lower at higher entrance velocities. Eels that investigated the bypass pipe entrance tended to enter headfirst, but those that then exited the pipe upstream did so more frequently at lower entrance velocities. Eels appeared to swim against the flow while being transported downstream through the pipe; median transit times through the bypass for each test velocity ranged from 5.8 to 12.2 s, with transit time decreasing with increasing entrance velocity. Eels did not show strong avoidance of the vertical section of the pipe which contained injected air. No mortality or injury of bypassed eels was observed, and individual eels repeatedly passed through the bypass at rates of up to 40 passes per hour, suggesting that individuals do not

  6. Recent Advances in Pediatric Cardiopulmonary Bypass. (United States)

    McRobb, Craig M; Mejak, Brian L; Ellis, W Cory; Lawson, D Scott; Twite, Mark D


    There have been numerous recent advances geared specifically toward the practice of pediatric cardiopulmonary bypass (CPB). These advances include the development of the first oxygenator intended solely for the neonatal CPB patient; pediatric oxygenators with low prime volumes and surface areas, which allow flows up to 2 L/min; pediatric oxygenators with integrated arterial filters; and miniature ultrafiltration (UF) devices, which allow for high rates of ultrafiltrate removal. When used in combination with heart lung machines with mast-mounted pumps, these advances can result in significant decreases in CPB circuit surface areas and prime volumes. This may attenuate CPB-associated hemodilution and decrease or eliminate the need for homologous red blood cells during or after CPB. In addition to these equipment-related advances, changes in myocardial protection strategies and the technique of modified UF as it relates to these advances are discussed. © The Author(s) 2014.

  7. Optimal filtering

    CERN Document Server

    Anderson, Brian D O


    This graduate-level text augments and extends beyond undergraduate studies of signal processing, particularly in regard to communication systems and digital filtering theory. Vital for students in the fields of control and communications, its contents are also relevant to students in such diverse areas as statistics, economics, bioengineering, and operations research.Topics include filtering, linear systems, and estimation; the discrete-time Kalman filter; time-invariant filters; properties of Kalman filters; computational aspects; and smoothing of discrete-time signals. Additional subjects e


    Directory of Open Access Journals (Sweden)

    V. V. Ivashechkin


    Full Text Available The purpose of this work is the study of decolmatation rate of granular layer of gravel pack of well during creating inside of it flushing of reagent with given hydrodynamic parameters and determination the duration of treatment. This article deals with radical movement of chemical solutions by injection of it outside of gravel pack of filter when the flow directs to borehole axis under conditions of quasi-steady-state mode of filtration for equal yield of input and output reagent from borehole.Colmataged layer of gravel pack is schematized in the form of porous ring cylinder with outside radius which is equal to radius of line of gravel pack and the height which is equal to the length of filter made in formation drilling and inside radius which is equal to radius of filter. Initial saturation of subsoil with colmatant is given. It was accepted that reagent with given rate flows through outside surface of ring cylinder equal along all height. Near-filtering zone is given uniform and movement is quasi-steady-state.Equations’ system is composed including: joint equation of movement and mass conservation and generalized equation of kinetics, which describes kinetics of colmatant dissolution in the regime of out-pipe watering of ring gravel pack of well taking into account the change of structure of porous medium. The analytic solution of equations’ system was obtained, which allow to calculate salt content in reagent during the leaching process and to determine the specific volume of deposits in the point of gravel pack at any moment of time in the process of regent injection. The analytic dependence was obtained for calculation of duration of complete regeneration of soil grains’ layer of outer contour of gravel packing. For calculation of duration of full regeneration of the whole thickness of packing it is suggested to divide the regeneration period into a series of stages of salt transferring from subsoil. Duration of one stage is equal

  9. Flow characteristics in narrowed coronary bypass graft

    Energy Technology Data Exchange (ETDEWEB)

    Bernad, S. I. [Romanian Academy – Timisoara Branch, Mihai Viteazul Str. 24, RO-300223, Timisoara (Romania); Bosioc, A.; Totorean, A. F. [University Politehnica of Timisoara, Department of Hydraulic Machinery, Mihai Viteazul Str. 1, RO-300222, Timisoara (Romania); Bernad, E. S.; Petre, I. [University of Medicine and Pharmacy Victor Babes Timisoara, P-ta Eftimie Murgu, 2, Timisoara (Romania)


    Tortuous saphenous vein graft (SVG) hemodynamics was investigated using computational fluid dynamics (CFD) techniques. Computed tomography (CT) technology is used for non-invasive bypass graft assessment 7 days after surgery. CT investigation shown two regions with severe shape remodelling first is an elbow type contortion and second is a severe curvature with tortuous area reduction. In conclusion, the helical flow induced by vessel torsion may stabilize the blood flow in the distal part of the SVG, reducing the flow disturbance and suppressing the flow separation, but in the distal end of the graft, promote the inflammatory processes in the vessels.

  10. Reconnaissance Report Yolo Bypass, California

    National Research Council Canada - National Science Library


    The purpose of this study was to investigate flooding and related water resources problems associated with the Yolo Bypass and determine the Federal interest in proceeding into feasibility phase studies...

  11. Heart bypass surgery - minimally invasive (United States)

    ... and lifestyle Cholesterol - drug treatment Controlling your high blood pressure Dietary fats explained Fast food tips Heart attack - discharge Heart attack - what to ask your doctor Heart bypass surgery - minimally invasive - discharge Heart disease - risk factors Heart pacemaker - discharge ...

  12. Fabric filter technology for utility coal-fired power plants. Part II. Application of baghouse technology in the electric utility industry

    Energy Technology Data Exchange (ETDEWEB)

    Carr, R.C.; Smith, W.B.


    This, the second in a series of papers, discusses the experience of electric utilities in applying baghouse technology for the collection of particulate matter at coal-fired electric power generating plants. The history of baghouse technology in the US is traced, and past and present research and development to build a data base for the technology in application in the electric utility industry is described.

  13. Long-term temporal stability of the National Institute of Standards and Technology spectral irradiance scale determined with absolute filter radiometers. (United States)

    Yoon, Howard W; Gibson, Charles E


    The temporal stability of the National Institute of Standards and Technology (NIST) spectral irradiance scale as measured with broadband filter radiometers calibrated for absolute spectral irradiance responsivity is described. The working standard free-electron laser (FEL) lamps and the check standard FEL lamps have been monitored with radiometers in the ultraviolet and the visible wavelength regions. The measurements made with these two radiometers reveal that the NIST spectral irradiance scale as compared with an absolute thermodynamic scale has not changed by more than 1.5% in the visible from 1993 to 1999. Similar measurements in the ultraviolet reveal that the corresponding change is less than 1.5% from 1995 to 1999. Furthermore, a check of the spectral irradiance scale by six different filter radiometers calibrated for absolute spectral irradiance responsivity based on the high-accuracy cryogenic radiometer shows that the agreement between the present scale and the detector-based scale is better than 1.3% throughout the visible to the near-infrared wavelength region. These results validate the assigned spectral irradiance of the widely disseminated NIST or NIST-traceable standard sources.

  14. Monolithic integrated filters - An overview (United States)

    Entenmann, W.


    An overview of the state of the art in monolithic integrated filter design is given. The close mutual influence of technology and network theory and the continuing development of filter designs with higher integration, higher reliability, lower costs and lower space demands are examined. The fundamental concepts of circuit theory and MOS technology are described and the principal construction of the components of the three major classes of MOS filter circuits examined, namely the change-transfer filter, the switched-capacitor filter and the digital filter. The most important properties, such as the periodicity of the spectra, the impulse response, as well as recursive, nonrecursive, linear and minimal phase filters are covered. Some methods for calculating filter circuits by using classical reactance filter synthesis with the aid of suitable transformations from analog time-continuous reference circuits are discussed. The obtainable signal frequency ranges and filter grades are shown in order to compare the efficiency and operating range of monolithic integrated filter circuits with each other and with other concepts.

  15. Evaluation of drinking water treatment combined filter backwash water recycling technology based on comet and micronucleus assay. (United States)

    Chen, Ting; Xu, Yongpeng; Liu, Zhiquan; Zhu, Shijun; Shi, Wenxin; Cui, Fuyi


    Based on the fact that recycling of combined filter backwash water (CFBW) directly to drinking water treatment plants (WTP) is considered to be a feasible method to enhance pollutant removal efficiency, we were motivated to evaluate the genotoxicity of water samples from two pilot-scale drinking water treatment systems, one with recycling of combined backwash water, the other one with a conventional process. An integrated approach of the comet and micronucleus (MN) assays was used with zebrafish (Danio rerio) to investigate the water genotoxicity in this study. The total organic carbon (TOC), dissolved organic carbon (DOC), and trihalomethane formation potential (THMFP), of the recycling process were lower than that of the conventional process. All the results showed that there was no statistically significant difference (P>0.05) between the conventional and recycling processes, and indicated that the genotoxicity of water samples from the recycling process did not accumulate in 15 day continuous recycling trial. It was worth noting that there was correlation between the concentrations of TOC, DOC, UV254, and THMFPs in water and the DNA damage score, with corresponding R(2) values of 0.68, 0.63, 0.28, and 0.64. Nevertheless, both DNA strand breaks and MN frequency of all water samples after disinfection were higher than that of water samples from the two treatment units, which meant that the disinfection by-products (DBPs) formed by disinfection could increase the DNA damage. Both the comet and MN tests suggest that the recycling process did not increase the genotoxicity risk, compared to the traditional process. Copyright © 2015. Published by Elsevier B.V.

  16. Practical investigations on monolithic integrated microwave filters


    Stephan, R; Möhring, J.


    Filters at microwave frequencies today normally are built in hybrid technology. In this paper principles for the monolit­hic integration of frequency selective structures without any external component are investigated. Monolithic Filters at frequencies about 10 GHz based on lumped LC-structures and about 30 GHz in coplanar waveguide technology are presented. Both filter concepts need active components to compensate the insertion loss of the filters. All components are interconnected by copla...

  17. Current peripheral bypass surgery: various clinical studies

    NARCIS (Netherlands)

    Slaa, Alexander te


    Substantial post-operative edema occurs in the majority of patients who undergo peripheral bypass surgery due to severe peripheral arterial disease (PAD). The pathophysiological mechanisms that underlay edema formation following peripheral bypass surgery include hyperemia, an increased capillary

  18. In situ bypass og diabetes

    DEFF Research Database (Denmark)

    Jensen, Leif Panduro; Schroeder, T V; Lorentzen, J E


    From 1986 through to 1990 a total of 483 in situ bypass procedures were performed in 444 patients. Preoperative risk-factors were equally distributed among diabetic (DM) and non-diabetic (NDM) patients, except for smoking habits (DM:48%, NDM:64%, p = 0.002) and cardiac disease (DM:45%, NDM:29%, p...... decreased survival rate was found in diabetics (p bypass technique very useful in the treatment of critical ischaemia of the lower limb in diabetic patients. The overall results in diabetic patients, whether insulin-dependent or not, were equal to those in non...

  19. Fabric filter technology for utility coal-fired power plants. Part I. Utility baghouse design and operation

    Energy Technology Data Exchange (ETDEWEB)

    Carr, R.C.; Smith, W.B.


    This is the first in a series of papers discussing the experience of electric utilities in applying baghouse technology for the collection of particulate matter at coal-fired electric power generating plants. The series presents new data obtained in research sponsored by the Electric Power Research Institute (EPRI) on reverse-gas and shake/deflate cleaned baghouses, and specifically addresses a number of unresolved issues in the design and operation of these units. The authors explain baghouse design and operation, and include discussions of utility boiler operation, fly ash characterization, and filtration mechanisms. 19 references.

  20. High flow ceramic pot filters

    NARCIS (Netherlands)

    van Halem, D.; van der Laan, H.; Soppe, A. I.A.; Heijman, S.G.J.


    Ceramic pot filters are considered safe, robust and appropriate technologies, but there is a general consensus that water revenues are limited due to clogging of the ceramic element. The objective of this study was to investigate the potential of high flow ceramic pot filters to produce more

  1. Undiagnosed phaeochromocytoma following infrainguinal bypass surgery

    DEFF Research Database (Denmark)

    Levi, N; Schroeder, T V


    We present a rare case of undiagnosed phaeochromocytoma following infrainguinal bypass surgery. The patient, a 59-year-old lady, had a one year history of hypertension following a first femoro-tibial bypass and presented as a cardiorespiratory emergency in the admission room following her...... contralateral femoro-tibial bypass. The patient recovered after some days in intensive care despite a delayed diagnosis....

  2. Deep-water sediment bypass

    NARCIS (Netherlands)

    Stevenson, Christopher J.; Jackson, Christopher A L; Hodgson, David M.; Hubbard, Stephen M.; Eggenhuisen, Joris T.|info:eu-repo/dai/nl/322850274

    Submarine gravity flows are a key process for transporting large volumes of sediment from the continents to the deep sea. The location, volume, and character of the sediment bypassed by these flows dictates the areal extent and thickness of the associated deposits. Despite its importance, sediment

  3. Choroidal changes after cardiopulmonary bypass. (United States)

    Pekel, G; Alur, I; Alihanoglu, Y I; Yagci, R; Emrecan, B


    Choroid, which is the vascular tissue responsible for blood supply to the outer parts of the retina, might be affected by hemodynamic events. We aimed to reveal choroidal thickness and ocular pulse amplitude changes after cardiopulmonary bypass in which gross hemodynamic alterations occur. Forty-two eyes of 42 patients who underwent heart surgery with cardiopulmonary bypass were examined in this prospective, cross-sectional case series. The spectral domain optical coherence tomography (Spectralis, Heidelberg, Germany) was used to analyze sub-foveal choroidal thickness. The ocular pulse amplitude, the surrogate of gross choroidal blood flow, was measured with the Pascal dynamic contour tonometer (Pascal DCT, Swiss Microtechnology AG, Port, Switzerland).. The intraocular pressure was also measured with this tonometer. The examinations were performed pre-operatively and post-operatively at the first week and first month. The mean age of the patients was 58.8 ± 12.4 years. The mean sub-foveal choroidal thickness and ocular pulse amplitude values did not change statistically significantly after the operations at the follow-up visits (p>0.05). Also, there were no important correlations between cardiopulmonary bypass time and mean sub-foveal choroidal thickness and ocular pulse amplitude changes at the post-operative first week (p>0.05). The intraocular pressure values were decreased markedly at the control visits (pcardiopulmonary bypass. © The Author(s) 2014.

  4. High flow ceramic pot filters. (United States)

    van Halem, D; van der Laan, H; Soppe, A I A; Heijman, S G J


    Ceramic pot filters are considered safe, robust and appropriate technologies, but there is a general consensus that water revenues are limited due to clogging of the ceramic element. The objective of this study was to investigate the potential of high flow ceramic pot filters to produce more water without sacrificing their microbial removal efficacy. High flow pot filters, produced by increasing the rice husk content, had a higher initial flow rate (6-19 L h-1), but initial LRVs for E. coli of high flow filters was slightly lower than for regular ceramic pot filters. This disadvantage was, however, only temporarily as the clogging in high flow filters had a positive effect on the LRV for E. coli (from below 1 to 2-3 after clogging). Therefore, it can be carefully concluded that regular ceramic pot filters perform better initially, but after clogging, the high flow filters have a higher flow rate as well as a higher LRV for E. coli. To improve the initial performance of new high flow filters, it is recommended to further utilize residence time of the water in the receptacle, since additional E. coli inactivation was observed during overnight storage. Although a relationship was observed between flow rate and LRV of MS2 bacteriophages, both regular and high flow filters were unable to reach over 2 LRV. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Ultra by-pass ratio engine

    Energy Technology Data Exchange (ETDEWEB)

    Endo, Masanori; Sugiyama, Shichihisa


    A engine where ratio of fan's or propeller's air flow rate to air flow rate through engine combustion chamber is more than 15 is generally named the ultra bypass ratio engine (UBE). This engine employs the exhaust gas from the engine separately to the fan or propeller and jet nozzle exhaust to obtain higher total thrust efficiency. The increase rate of thrust by using UBE is equal to the improvement rate of fuel comsumption. Much efforts are continuously made to develop UBE toward the 21 century by many companies and it is necessary to develop the core engine of high specific output and high heat efficiency, and variable pitch / high aspect ratio fan or propeller and to reseach the integrated system technology. (5 refs, 9 figs)

  6. The usefulness of DNA sequencing after extraction by Whatman FTA filter matrix technology and phenotypic tests for differentiation of Candida albicans and Candida dubliniensis. (United States)

    Kiraz, Nuri; Oz, Yasemin; Aslan, Huseyin; Muslumanoglu, Hamza


    Since C. dubliniensis is similar to C. albicans phenotypically, it can be misidentified as C. albicans. We aimed to investigate the prevalence of C. dubliniensis among isolates previously identified as C. albicans in our stocks and to compare the phenotypic methods and DNA sequencing of D1/D2 region on the ribosomal large subunit (rLSU) gene. A total of 850 isolates included in this study. Phenotypic identification was performed based on germ tube formation, chlamydospore production, colony colors on chromogenic agar, inability of growth at 45 °C and growth on hypertonic Sabouraud dextrose agar. Eighty isolates compatible with C. dubliniensis by at least one phenotypic test were included in the sequence analysis. Nested PCR amplification of D1/D2 region of the rLSU gene was performed after the fungal DNA extraction by Whatman FTA filter paper technology. The sequencing analysis of PCR products carried out by an automated capillary gel electrophoresis device. The rate of C. dubliniensis was 2.35 % (n = 20) among isolates previously described as C. albicans. Consequently, none of the phenotypic tests provided satisfactory performance alone in our study, and molecular methods required special equipment and high cost. Thus, at least two phenotypic methods can be used for identification of C. dubliniensis, and molecular methods can be used for confirmation.

  7. Hands-on defibrillation and electrocardiogram artefact filtering technology increases chest compression fraction and decreases peri-shock pause duration in a simulation model of cardiac arrest. (United States)

    Fernando, Shannon M; Cheskes, Sheldon; Howes, Daniel


    Reducing pauses during cardiopulmonary resuscitation (CPR) compressions result in better outcomes in cardiac arrest. Artefact filtering technology (AFT) gives rescuers the opportunity to visualize the underlying electrocardiogram (ECG) rhythm during chest compressions, and reduces the pauses that occur before and after delivering a shock. We conducted a simulation study to measure the reduction of peri-shock pause and impact on chest compression fraction (CCF) through AFT. In a simulator setting, participants were given a standardized cardiac arrest scenario and were randomly assigned to perform CPR/defibrillation using the protocol from one of three experimental arms: 1) Standard of Care (pauses for rhythm analysis and shock delivery); 2) AFT (no pauses for rhythm analysis, but a pause for defibrillation); or 3) AFT with hands-on defibrillation (no pauses for rhythm analysis or defibrillation). The primary outcomes were CCF and peri-shock pause duration, with secondary outcomes of pre- and post-shock pause duration. AFT with hands-on defibrillation was found to have the highest CCF (86.4%), as compared to AFT alone (83.8%, pdefibrillation was associated with a reduced peri-shock pause (2.6 seconds) as compared to AFT alone (5.3 seconds, pdefibrillation.

  8. Water Filters (United States)


    Seeking to find a more effective method of filtering potable water that was highly contaminated, Mike Pedersen, founder of Western Water International, learned that NASA had conducted extensive research in methods of purifying water on board manned spacecraft. The key is Aquaspace Compound, a proprietary WWI formula that scientifically blends various types of glandular activated charcoal with other active and inert ingredients. Aquaspace systems remove some substances; chlorine, by atomic adsorption, other types of organic chemicals by mechanical filtration and still others by catalytic reaction. Aquaspace filters are finding wide acceptance in industrial, commercial, residential and recreational applications in the U.S. and abroad.

  9. Filter apparatus (United States)

    Kuban, D.P.; Singletary, B.H.; Evans, J.H.

    A plurality of holding tubes are respectively mounted in apertures in a partition plate fixed in a housing receiving gas contaminated with particulate material. A filter cartridge is removably held in each holding tube, and the cartridges and holding tubes are arranged so that gas passes through apertures therein and across the the partition plate while particulate material is collected in the cartridges. Replacement filter cartridges are respectively held in holding canisters mounted on a support plate which can be secured to the aforesaid housing, and screws mounted on said canisters are arranged to push replacement cartridges into the cartridge holding tubes and thereby eject used cartridges therefrom.

  10. Gut hormones and gastric bypass

    DEFF Research Database (Denmark)

    Holst, Jens J.


    Gut hormone secretion in response to nutrient ingestion appears to depend on membrane proteins expressed by the enteroendocrine cells. These include transporters (glucose and amino acid transporters), and, in this case, hormone secretion depends on metabolic and electrophysiological events elicited...... that determines hormone responses. It follows that operations that change intestinal exposure to and absorption of nutrients, such as gastric bypass operations, also change hormone secretion. This results in exaggerated increases in the secretion of particularly the distal small intestinal hormones, GLP-1, GLP-2......, oxyntomodulin, neurotensin and peptide YY (PYY). However, some proximal hormones also show changes probably reflecting that the distribution of these hormones is not restricted to the bypassed segments of the gut. Thus, cholecystokinin responses are increased, whereas gastric inhibitory polypeptide responses...

  11. Arrhythmias after coronary bypass surgery.


    Ormerod, O J; McGregor, C G; Stone, D L; Wisbey, C; Petch, M C


    Ninety patients undergoing coronary bypass surgery were studied prospectively by bedside and subsequent ambulatory electrocardiographic monitoring to investigate the incidence, possible causes, and prevention of atrial fibrillation. Patients with good left ventricular function were divided randomly into a control group or groups treated with digoxin or propranolol. In the control group the incidence of atrial fibrillation was 27% and of significant ventricular extrasystoles 3%. Propranolol re...

  12. Filter This

    Directory of Open Access Journals (Sweden)

    Audrey Barbakoff


    Full Text Available In the Library with the Lead Pipe welcomes Audrey Barbakoff, a librarian at the Milwaukee Public Library, and Ahniwa Ferrari, Virtual Experience Manager at the Pierce County Library System in Washington, for a point-counterpoint piece on filtering in libraries. The opinions expressed here are those of the authors, and are not endorsed by their employers. [...


    Directory of Open Access Journals (Sweden)

    Yoel Abreu-Lee


    Full Text Available La vigilancia tecnológica en centros de investigación y universidades está enfocada a realizar un seguimiento sistemático sobre el desarrollo de líneas de investigación, investigadores líderes, posibilidades de colaboración científico-tecnológica y también al conocimiento de las tendencias actuales desde la investigación. Todo lo anteriormente expresado permite guiar las investigaciones y apoyar la estrategia científico-tecnológica. El presente trabajo propone un modelo de vigilancia tecnológica apoyado de un sistema de recomendaciones, como una aplicación que está centrada en las preferencias de los investigadores en universidades y centros de investigación. Para proponer las recomendaciones se emplea el filtrado colaborativo, técnica que utiliza información del comportamiento pasado de los investigadores y de las opiniones o valoraciones de la comunidad científica a la que pertenecen. Este nuevo enfoque permite realizar propuestas de colaboración y temas de interés que se discuten en la comunidad científica en la que tiene lugar, de manera automática y proactiva.AbstractTechnology surveillance has a special place nowadays, in the success and development of R+D+i process, in research centers and academic environment. Technology surveillance in universities and research centers is focused in the constant analysis of the research lines, research leaders, collaborations chances and current trends in specific research fields. This paper presents a technology surveillance model supported by recommendations by an application that takes into account the preferences of the researchers in the academic environment. The recommender system uses the collaborative filtering technique in order to compute the behavior and past user interactions and infer the recommendations. This approach allows recommending useful, automatic and proactive collaboration possibilities and topics of interest which are discussed within the scientific

  14. Cardiopulmonary bypass for pediatric cardiac surgery. (United States)

    Hirata, Yasutaka


    The management of cardiopulmonary bypass for pediatric cardiac surgery is more challenging than that in adults due to the smaller size, immaturity, and complexity of the anatomy in children. Despite major improvements in cardiopulmonary bypass, there remain many subjects of debate. This review article discusses the physiology of cardiopulmonary bypass for pediatric and congenital heart surgery, including topics related to hemodilution, hypothermia, acid-base strategies, inflammatory response, and myocardial protection.

  15. Water Filter (United States)


    A compact, lightweight electrolytic water sterilizer available through Ambassador Marketing, generates silver ions in concentrations of 50 to 100 parts per billion in water flow system. The silver ions serve as an effective bactericide/deodorizer. Tap water passes through filtering element of silver that has been chemically plated onto activated carbon. The silver inhibits bacterial growth and the activated carbon removes objectionable tastes and odors caused by addition of chlorine and other chemicals in municipal water supply. The three models available are a kitchen unit, a "Tourister" unit for portable use while traveling and a refrigerator unit that attaches to the ice cube water line. A filter will treat 5,000 to 10,000 gallons of water.

  16. Gastric bypass reduces fat intake and preference (United States)

    Bueter, Marco; Theis, Nadine; Werling, Malin; Ashrafian, Hutan; Löwenstein, Christian; Athanasiou, Thanos; Bloom, Stephen R.; Spector, Alan C.; Olbers, Torsten; Lutz, Thomas A.


    Roux-en-Y gastric bypass is the most effective therapy for morbid obesity. This study investigated how gastric bypass affects intake of and preference for high-fat food in an experimental (rat) study and within a trial setting (human). Proportion of dietary fat in gastric bypass patients was significantly lower 6 yr after surgery compared with patients after vertical-banded gastroplasty (P = 0.046). Gastric bypass reduced total fat and caloric intake (P bypass rats displayed much lower preferences for Intralipid concentrations > 0.5% in an ascending concentration series (0.005%, 0.01%, 0.05%, 0.1%, 0.5%, 1%, 5%) of two-bottle preference tests (P = 0.005). This effect was demonstrated 10 and 200 days after surgery. However, there was no difference in appetitive or consummatory behavior in the brief access test between the two groups (P = 0.71) using similar Intralipid concentrations (0.005% through 5%). Levels of glucagon-like peptide-1 (GLP-1) were increased after gastric bypass as expected. An oral gavage of 1 ml corn oil after saccharin ingestion in gastric bypass rats induced a conditioned taste aversion. These findings suggest that changes in fat preference may contribute to long-term maintained weight loss after gastric bypass. Postingestive effects of high-fat nutrients resulting in conditioned taste aversion may partially explain this observation; the role of GLP-1 in mediating postprandial responses after gastric bypass requires further investigation. PMID:21734019

  17. A comparison of haemodynamics between subcranial-intracranial bypass and the traditional extracranial-intracranial bypass. (United States)

    Yu, Zaitao; Yang, Yang; Shi, Xiang'en; Qian, Hai; Liu, Fangjun


    Ischemic cerebrovascular diseases are traditionally treated using an extracranial-intracranial (EC-IC) bypass. The use of the internal maxillary artery (IMA) in the subcranial-intracranial (SC-IC) bypass was recently described as an alternative treatment. However, the haemodynamics of this new approach have not been defined. The haemodynamic parameters (flow volume [FV], internal diameter [ID], time-averaged mean velocity [TAM], pulsatility index [PI] and resistance index [RI]) of the IMA-radial artery graft (RAG)-middle cerebral artery (MCA) (n = 12) bypass and superficial temporal artery (STA)-MCA bypass (n = 18) were measured using intraoperative duplex ultrasonography and compared. The FV was 81.36 ± 30.41 (62.05-100.70) ml/min for the IMA-RAG-MCA bypass. This was significantly higher than that of the STA-MCA bypass (27.25 ± 9.32 (22.62-31.88) ml/min; P bypass were higher than in the STA-MCA bypass (P bypass and 94% for the STA-MCA bypass. The IMA-RAG-MCA bypass provides moderate to high blood flow to the revascularized territory and blood flow was higher by this method than the STA-MCA bypass.

  18. A Series-LC-Filtered Active Trap Filter for High Power Voltage Source Inverter

    DEFF Research Database (Denmark)

    Bai, Haofeng; Wang, Xiongfei; Loh, Poh Chiang


    Passive trap filters are widely used in high power Voltage Source Inverters (VSI) for the switching harmonic attenuation. The usage of the passive trap filters requires clustered and fixed switching harmonic spectrum, which is not the case for low pulse-ratio or Variable Switching Frequency (VSF...... current control of the auxiliary converter, which can be challenging considering that the switching harmonics have very high orders. In this paper, an Active Trap Filter (ATF) based on output impedance shaping is proposed. It is able to bypass the switching harmonics by providing nearly zero output...... impedance. A series-LC-filter is used to reduce the power rating and synthesize the desired output impedance of the ATF. Compared with the existing approaches, the compensated frequency range is greatly enlarged. Also, the current reference is simply set to zero, which reduces the complexity of the control...

  19. In vitro air removal characteristics of two neonatal cardiopulmonary bypass systems : filtration may lead to fractionation of bubbles

    NARCIS (Netherlands)

    Stehouwer, Marco C.; Kelder, Johannes C.; van Oeveren, Willem; de Vroege, Roel

    Introduction of gaseous microemboli (GME) into the arterial line of a pediatric cardiopulmonary bypass (CPB) circuit may lead to cognitive decline and adverse outcomes of the pediatric patient. Arterial filters are incorporated into CPB circuits as a safeguard for gross air and to reduce GME.

  20. Coronary bypass grafting without use of cardiopulmonary bypass for dextrocardia. (United States)

    Mujanovic, Emir; Bergsland, Jacob; Tursic, Ademir; Stanimirovic-Mujanovic, Sanja; Kabil, Emir


    Dextrocardia is a condition in which the heart is pointed toward the right side of the chest instead of normally pointing to the left. The rate of atherosclerotic heart disease in subjects with this condition is similar to that of the general population. We present a patient with situs inversus totalis with dextrocardia who underwent coronary artery bypass grafting without use of cardiopulmonary bypass (OPCAB). A 74-year-old man who was known to have dextrocardia with situs inversus was admitted to the hospital because of angina. Coronary angiography was performed and showed ostial occlusion of the left anterior descendng artery (LAD) unsuitable for percutaneous coronary interventions but collatereralised from the right coronary artery. Patient underwent OPCAB under general anestesia. Right internal mammary artery was anastomosed to LAD on the beating heart with the surgeon standing on the right side of the patient. The patient's post-operative course was uneventful, and he was discharged on the 6th postoperative day in good condition. Performing OPCAB surgery is not technically more demanding, and present no unusual challenge on patients with dextrocardia.

  1. Coronary Artery Bypass in Octogenarians

    Directory of Open Access Journals (Sweden)

    Chen-Yen Chien


    Full Text Available Prevalence of coronary artery disease (CAD has increased with the expansion of life span among the elderly population in the world. Hence, the issue of the coronary artery bypass in octogenarians has attracted more attention. Recent literature about the topic revealed nearly the same excellent results as those in the younger population under the newly developed operative techniques and improving concept in perioperative management and postoperative care. In this article, we review the current status of the procedure that was thought to be dangerous in the earlier era, including its risk factors, result, and benefit.

  2. Ceramic HEPA Filter Program

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, M A; Bergman, W; Haslam, J; Brown, E P; Sawyer, S; Beaulieu, R; Althouse, P; Meike, A


    Potential benefits of ceramic filters in nuclear facilities: (1) Short term benefit for DOE, NRC, and industry - (a) CalPoly HTTU provides unique testing capability to answer questions for DOE - High temperature testing of materials, components, filter, (b) Several DNFSB correspondences and presentations by DNFSB members have highlighted the need for HEPA filter R and D - DNFSB Recommendation 2009-2 highlighted a nuclear facility response to an evaluation basis earthquake followed by a fire (aka shake-n-bake) and CalPoly has capability for a shake-n-bake test; (2) Intermediate term benefit for DOE and industry - (a) Filtration for specialty applications, e.g., explosive applications at Nevada, (b) Spin-off technologies applicable to other commercial industries; and (3) Long term benefit for DOE, NRC, and industry - (a) Across industry, strong desire for better performance filter, (b) Engineering solution to safety problem will improve facility safety and decrease dependence on associated support systems, (c) Large potential life-cycle cost savings, and (d) Facilitates development and deployment of LLNL process innovations to allow continuous ventilation system operation during a fire.

  3. Filtration of activated granulocytes during cardiopulmonary bypass surgery: a morphologic and immunologic study to characterize the trapped leukocytes. (United States)

    Smit, J J; de Vries, A J; Gu, Y J; van Oeveren, W


    Cardiopulmonary bypass surgery induces an inflammatory reaction among others by activation of granulocytes. Leukocyte filtration has been shown to reduce the postoperative morbidity mediated by activated granulocytes. However, little is known about the mechanism of filter-leukocyte interaction. This study examines whether a leukocyte filter removes activated granulocytes or a general leukocyte population. Eleven patients undergoing cardiopulmonary bypass surgery were included in this study. Leukocyte filtration was achieved before the reperfusion phase with a Pall non-woven polyester filter located at the venous side of the heart-lung machine. After filtration, the trapped granulocytes inside the filter were examined morphologically with light and scanning electron microscopy and immunologically by CD45RO antigen binding to the filter material. Furthermore, leukocyte release markers were measured to determine whether cells were activated during filtration. Microscopic evaluation revealed 84% granulocytes and 14% lymphocytes trapped in the filter, compared with 78% granulocytes and 22% lymphocytes in the blood before filtration. Granulocytes were trapped significantly more in the first blood contact layer of the filter material than in the middle layer and last layer, whereas lymphocytes trapped slightly more in the middle layer. The near maximum level of CD45RO expression was measured on granulocytes trapped inside the filter material, whereas CD2 and CD19 measured on lymphocytes were bound to a minor extent. Beta-glucuronidase concentration did not increase after filtration, suggesting the absence of activation of granulocytes by filtration. A leukocyte filter made of non-woven polyester material removes the activated granulocytes rather than leukocytes at random. This implies that this particular type of leukocyte removal filter is suitable for use in cardiopulmonary bypass patients whose granulocytes in the circulation are activated. Furthermore, measurement of

  4. Tunable Multiband Microwave Photonic Filters

    Directory of Open Access Journals (Sweden)

    Mable P. Fok


    Full Text Available The increasing demand for multifunctional devices, the use of cognitive wireless technology to solve the frequency resource shortage problem, as well as the capabilities and operational flexibility necessary to meet ever-changing environment result in an urgent need of multiband wireless communications. Spectral filter is an essential part of any communication systems, and in the case of multiband wireless communications, tunable multiband RF filters are required for channel selection, noise/interference removal, and RF signal processing. Unfortunately, it is difficult for RF electronics to achieve both tunable and multiband spectral filtering. Recent advancements of microwave photonics have proven itself to be a promising candidate to solve various challenges in RF electronics including spectral filtering, however, the development of multiband microwave photonic filtering still faces lots of difficulties, due to the limited scalability and tunability of existing microwave photonic schemes. In this review paper, we first discuss the challenges that were facing by multiband microwave photonic filter, then we review recent techniques that have been developed to tackle the challenge and lead to promising developments of tunable microwave photonic multiband filters. The successful design and implementation of tunable microwave photonic multiband filter facilitate the vision of dynamic multiband wireless communications and radio frequency signal processing for commercial, defense, and civilian applications.

  5. Digital filters

    CERN Document Server

    Hamming, Richard W


    Digital signals occur in an increasing number of applications: in telephone communications; in radio, television, and stereo sound systems; and in spacecraft transmissions, to name just a few. This introductory text examines digital filtering, the processes of smoothing, predicting, differentiating, integrating, and separating signals, as well as the removal of noise from a signal. The processes bear particular relevance to computer applications, one of the focuses of this book.Readers will find Hamming's analysis accessible and engaging, in recognition of the fact that many people with the s

  6. Filtered or Unfiltered? (United States)

    Curry, Ann; Haycock, Ken


    Discusses results of a survey questionnaire of public and school libraries that investigated the use of Internet filtering software. Considers filter alternatives; reasons for filtering or not filtering; brand names; satisfaction with site blocking; satisfaction with the decision to install filter software; and guidelines for considering filters.…

  7. Strategies for optimisation of paediatric cardiopulmonary bypass

    NARCIS (Netherlands)

    Somer, Filip Maria Jan Jozef De


    The aim of this thesis is to address different aspects of paediatric cardiopulmonary bypass in detail and to propose modifications in order to reduce cardiopulmonary bypass related morbidity and by doing so, improve patient outcome. We will focus on four major items: (1) vascular access, (2) mass

  8. Cephalic veins in coronary artery bypass surgery

    DEFF Research Database (Denmark)

    Licht, P; Jakobsen, Erik; Lerbjerg, G


    Various alternative conduits for aortocoronary bypass grafting have been suggested when the saphenous vein quality is inadequate. During a 10-year period we have used the cephalic vein in 39 patients. Eighteen entered an angiographic follow-up study. A total of 31 arm vein grafts were used with 43...... bypass operations....

  9. Multimodality imaging of coronary artery bypass grafts

    NARCIS (Netherlands)

    Salm, Liesbeth Pauline


    This thesis describes multiple imaging modalities to examine coronary artery bypass grafts, and the research which was performed to further develop noninvasive imaging techniques to detect stenoses in native coronary arteries and bypass grafts in patients who experienced recurrent chest pain after

  10. Epicardial ultrasound in coronary artery bypass surgery

    NARCIS (Netherlands)

    Budde, R.P.J.


    Chapter 1 Coronary artery bypass surgery (CABG) is traditionally performed via a median sternotomy approach on cardiopulmonary bypass (arrested heart). Since the mid 1990ties, beating heart, minimally invasive and even totally endoscopic CABG are (re)explored. In all approaches to CABG, the

  11. In-place HEPA filter penetration test

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, W.; Wilson, K.; Elliott, J. [Lawrence Livermore National Lab., CA (United States)] [and others


    We have demonstrated the feasibility of conducting penetration tests on high efficiency particulate air (HEPA) filters as installed in nuclear ventilation systems. The in-place penetration test, which is designed to yield equivalent penetration measurements as the standard DOP efficiency test, is based on measuring the aerosol penetration of the filter installation as a function of particle size using a portable laser particle counter. This in-place penetration test is compared to the current in-place leak test using light scattering photometers for single HEPA filter installations and for HEPA filter plenums using the shroud method. Test results show the in-place penetration test is more sensitive than the in-place leak test, has a similar operating procedure, but takes longer to conduct. Additional tests are required to confirm that the in-place penetration test yields identical results as the standard dioctyl phthalate (DOP) penetration test for HEPA filters with controlled leaks in the filter and gasket and duct by-pass leaks. Further development of the procedure is also required to reduce the test time before the in-place penetration test is practical. 14 refs., 14 figs., 3 tabs.

  12. Structured filtering (United States)

    Granade, Christopher; Wiebe, Nathan


    A major challenge facing existing sequential Monte Carlo methods for parameter estimation in physics stems from the inability of existing approaches to robustly deal with experiments that have different mechanisms that yield the results with equivalent probability. We address this problem here by proposing a form of particle filtering that clusters the particles that comprise the sequential Monte Carlo approximation to the posterior before applying a resampler. Through a new graphical approach to thinking about such models, we are able to devise an artificial-intelligence based strategy that automatically learns the shape and number of the clusters in the support of the posterior. We demonstrate the power of our approach by applying it to randomized gap estimation and a form of low circuit-depth phase estimation where existing methods from the physics literature either exhibit much worse performance or even fail completely.

  13. Augmented reality-assisted bypass surgery: embracing minimal invasiveness. (United States)

    Cabrilo, Ivan; Schaller, Karl; Bijlenga, Philippe


    The overlay of virtual images on the surgical field, defined as augmented reality, has been used for image guidance during various neurosurgical procedures. Although this technology could conceivably address certain inherent problems of extracranial-to-intracranial bypass procedures, this potential has not been explored to date. We evaluate the usefulness of an augmented reality-based setup, which could help in harvesting donor vessels through their precise localization in real-time, in performing tailored craniotomies, and in identifying preoperatively selected recipient vessels for the purpose of anastomosis. Our method was applied to 3 patients with Moya-Moya disease who underwent superficial temporal artery-to-middle cerebral artery anastomoses and 1 patient who underwent an occipital artery-to-posteroinferior cerebellar artery bypass because of a dissecting aneurysm of the vertebral artery. Patients' heads, skulls, and extracranial and intracranial vessels were segmented preoperatively from 3-dimensional image data sets (3-dimensional digital subtraction angiography, angio-magnetic resonance imaging, angio-computed tomography), and injected intraoperatively into the operating microscope's eyepiece for image guidance. In each case, the described setup helped in precisely localizing donor and recipient vessels and in tailoring craniotomies to the injected images. The presented system based on augmented reality can optimize the workflow of extracranial-to-intracranial bypass procedures by providing essential anatomical information, entirely integrated to the surgical field, and help to perform minimally invasive procedures. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Coronary arteries bypass grafting stenosis

    Directory of Open Access Journals (Sweden)

    Mahmoud Ebrahimi


    Full Text Available Coronary artery disease (CAD is a major global problem. In addition, it is higher risk of mortality for women more than men are when develop in female gender Atherosclerotic plaques consist of deposits of fatty material in the tunica intima. The role of inflammatory process in CAD has been known from 1980’s. Several studies investigated the innate immunity and adaptive immunity roles in atherosclerosis and they concluded that it plays a key role in atherosclerosis. Coronary artery bypass grafting (CABG is a widely used method for the treatment of CAD. Based on the literature, CABG is the most common surgical operation done worldwide. In During the first 10 years after CABG, up to 50% of saphenous grafts will occlude. Graft restenosis is beginning with acute thrombosis, intima hyperplasia, and plaque formation. In this review, some molecular pathways of graft failure and restenosis such as apoptosis and nuclear factor kappa B (NF-ĸB are described.

  15. Cardiopulmonary Bypass and Oxidative Stress (United States)

    Zakkar, Mustafa; Guida, Gustavo; Suleiman, M-Saadeh; Angelini, Gianni D.


    The development of the cardiopulmonary bypass (CPB) revolutionized cardiac surgery and contributed immensely to improved patients outcomes. CPB is associated with the activation of different coagulation, proinflammatory, survival cascades and altered redox state. Haemolysis, ischaemia, and perfusion injury and neutrophils activation during CPB play a pivotal role in oxidative stress and the associated activation of proinflammatory and proapoptotic signalling pathways which can affect the function and recovery of multiple organs such as the myocardium, lungs, and kidneys and influence clinical outcomes. The administration of agents with antioxidant properties during surgery either intravenously or in the cardioplegia solution may reduce ROS burst and oxidative stress during CPB. Alternatively, the use of modified circuits such as minibypass can modify both proinflammatory responses and oxidative stress. PMID:25722792

  16. Capacity analysis of a bypass of roundabouts (United States)

    Sedlačik, Ivan; Slabý, Petr


    The capacity of the roads network mainly depends on the capacity of its nodal points - intersections. A connecting branch or a bypass is a lane or lanes inserted between two adjacent branches of a roundabout, providing redirection of vehicles, that would otherwise burden a circular lane. A bypass effect to the capacity of roundabouts, but also other types of level intersections, is undeniable. A connecting branch increases the total capacity of an intersection that takes a part of vehicles performing a manoeuver of the first right turn completely out of an intersection area. Redirecting vehicles reduces delay times at intersections and reduces queues at the entrance to an intersection. Bypasses improve the quality of transport. Limiting for the capacity of bypasses is the point of disconnection from the entrance into the roundabout and the connection point into the exit from the roundabout. Central parts of the bypasses have minimal effects on the capacity. The length of a bypass has to match with the maximum length of a queue of waiting vehicles at a given intensity level. The article deals with analysis of the bypass capacity at the roundabouts.


    Energy Technology Data Exchange (ETDEWEB)

    E.S. Connolly; G.D. Forsythe


    DuPont Lanxide Composites, Inc. undertook a sixty-month program, under DOE Contract DEAC21-94MC31214, in order to develop hot gas candle filters from a patented material technology know as PRD-66. The goal of this program was to extend the development of this material as a filter element and fully assess the capability of this technology to meet the needs of Pressurized Fluidized Bed Combustion (PFBC) and Integrated Gasification Combined Cycle (IGCC) power generation systems at commercial scale. The principal objective of Task 3 was to build on the initial PRD-66 filter development, optimize its structure, and evaluate basic material properties relevant to the hot gas filter application. Initially, this consisted of an evaluation of an advanced filament-wound core structure that had been designed to produce an effective bulk filter underneath the barrier filter formed by the outer membrane. The basic material properties to be evaluated (as established by the DOE/METC materials working group) would include mechanical, thermal, and fracture toughness parameters for both new and used material, for the purpose of building a material database consistent with what is being done for the alternative candle filter systems. Task 3 was later expanded to include analysis of PRD-66 candle filters, which had been exposed to actual PFBC conditions, development of an improved membrane, and installation of equipment necessary for the processing of a modified composition. Task 4 would address essential technical issues involving the scale-up of PRD-66 candle filter manufacturing from prototype production to commercial scale manufacturing. The focus would be on capacity (as it affects the ability to deliver commercial order quantities), process specification (as it affects yields, quality, and costs), and manufacturing systems (e.g. QA/QC, materials handling, parts flow, and cost data acquisition). Any filters fabricated during this task would be used for product qualification tests

  18. Filter-extruded liposomes revisited

    DEFF Research Database (Denmark)

    Hinna, Askell; Steiniger, Frank; Hupfeld, Stefan


    (pore-size, number of filter passages, and flow-rate), flow field-flow fractionation in conjunction with multi-angle laser light scattering (AF4-MALLS, Wyatt Technology Corp., Santa Barbara, CA) was employed. Liposome size-distributions determined by AF4-MALLS were compared with those of dynamic light...... scattering and correlated with cryo-transmission electron microscopy and 31P-NMR-analysis of lamellarity. Both the mean size of liposome and the width of size distribution were found to decrease with sequential extrusion through smaller pore size filters, starting at a size range of &70–415nm upon repeated...... extrusion through 400nm pore-filters, eventually ending with a size range from &30 to 85nm upon extrusion through 30nm pore size filters. While for small pores sizes (50 nm), increased flow rates resulted in smaller vesicles, no significant influence of flow rate on mean vesicle size was seen with larger...

  19. 21 CFR 870.4205 - Cardiopulmonary bypass bubble detector. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass bubble detector. 870.4205... bypass bubble detector. (a) Identification. A cardiopulmonary bypass bubble detector is a device used to detect bubbles in the arterial return line of the cardiopulmonary bypass circuit. (b) Classification...

  20. 21 CFR 870.4380 - Cardiopulmonary bypass pump speed control. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass pump speed control. 870... Cardiopulmonary bypass pump speed control. (a) Identification. A cardiopulmonary bypass pump speed control is a... control the speed of blood pumps used in cardiopulmonary bypass surgery. (b) Classification. Class II...

  1. 21 CFR 870.4390 - Cardiopulmonary bypass pump tubing. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass pump tubing. 870.4390... bypass pump tubing. (a) Identification. A cardiopulmonary bypass pump tubing is polymeric tubing which is... through the cardiopulmonary bypass circuit. (b) Classification. Class II (performance standards). ...

  2. 21 CFR 870.4200 - Cardiopulmonary bypass accessory equipment. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass accessory equipment. 870... Cardiopulmonary bypass accessory equipment. (a) Identification. Cardiopulmonary bypass accessory equipment is a device that has no contact with blood and that is used in the cardiopulmonary bypass circuit to support...

  3. 21 CFR 870.4420 - Cardiopulmonary bypass cardiotomy return sucker. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass cardiotomy return sucker... Cardiopulmonary bypass cardiotomy return sucker. (a) Identification. A cardiopulmonary bypass cardiotomy return... from the chest or heart during cardiopulmonary bypass surgery. (b) Classification. Class II...

  4. 21 CFR 870.4350 - Cardiopulmonary bypass oxygenator. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass oxygenator. 870.4350... bypass oxygenator. (a) Identification. A cardiopulmonary bypass oxygenator is a device used to exchange... the FDA guidance document entitled “Guidance for Cardiopulmonary Bypass Oxygenators 510(k) Submissions...

  5. 21 CFR 870.4310 - Cardiopulmonary bypass coronary pressure gauge. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass coronary pressure gauge... Cardiopulmonary bypass coronary pressure gauge. (a) Identification. A cardiopulmonary bypass coronary pressure gauge is a device used in cardiopulmonary bypass surgery to measure the pressure of the blood perfusing...

  6. 21 CFR 870.4320 - Cardiopulmonary bypass pulsatile flow generator. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass pulsatile flow generator... Cardiopulmonary bypass pulsatile flow generator. (a) Identification. A cardiopulmonary bypass pulsatile flow... device is placed in a cardiopulmonary bypass circuit downstream from the oxygenator. (b) Classification...

  7. Convergent Filter Bases

    Directory of Open Access Journals (Sweden)

    Coghetto Roland


    Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.

  8. Coronary Bypass Surgery in a 105-Year-Old Patient with Cardiopulmonary Bypass

    Directory of Open Access Journals (Sweden)

    Temucin Noyan Ogus


    Full Text Available Coronary artery bypass grafting is one of the routine daily surgical procedures in the current era. Parallel to the increasing life expectancy, cardiac surgery is commonly performed in octogenarians. However, literature consists of only seldom reports of coronary artery bypass grafting in patients above 90 years of age. In this report, we present our management strategy in a 105-year-old patient who underwent coronary artery bypass grafting at our institution.

  9. Collaborative Research on the Ultra High Bypass Ratio Engine Cycle to Reduce Noise, Emissions and Fuel Consumption (United States)

    Hughes, Christopher


    A pictorial history of NASA development of advanced engine technologies for reducing environmental emissions and increasing performance from the 1970s to present is presented. The goals of the Subsonic Fixed Wing Program portion of the NASA Fundamental Aeronautics Program are addressed, along with the areas of investigation currently being pursued by the Ultra High Bypass Partnership Element of the Subsonic Fixed Wing Program to meet the goals. Ultra High Bypass cycle research collaboration successes with Pratt & Whitney are presented.

  10. Vacuum-assisted drainage in cardiopulmonary bypass: advantages and disadvantages. (United States)

    Carvalho Filho, Elio Barreto de; Marson, Fernando Augusto de Lima; Costa, Loredana Nilkenes Gomes da; Antunes, Nilson


    Systematic review of vacuum assisted drainage in cardiopulmonary bypass, demonstrating its advantages and disadvantages, by case reports and evidence about its effects on microcirculation. We conducted a systematic search on the period 1997-2012, in the databases PubMed, Medline, Lilacs and SciELO. Of the 70 selected articles, 26 were included in the review. Although the vacuum assisted drainage has significant potential for complications and requires appropriate technology and professionalism, prevailed in literature reviewed the concept that vacuum assisted drainage contributed in reducing the rate of transfusions, hemodilutions, better operative field, no significant increase in hemolysis, reduced complications surgical, use of lower prime and of smaller diameter cannulas.

  11. Exhaust gas bypass valve control for thermoelectric generator (United States)

    Reynolds, Michael G; Yang, Jihui; Meisner, Greogry P.; Stabler, Francis R.; De Bock, Hendrik Pieter Jacobus; Anderson, Todd Alan


    A method of controlling engine exhaust flow through at least one of an exhaust bypass and a thermoelectric device via a bypass valve is provided. The method includes: determining a mass flow of exhaust exiting an engine; determining a desired exhaust pressure based on the mass flow of exhaust; comparing the desired exhaust pressure to a determined exhaust pressure; and determining a bypass valve control value based on the comparing, wherein the bypass valve control value is used to control the bypass valve.

  12. A Simple Differential Mode EMI Suppressor for the LLCL-Filter-Based Single-Phase Grid-Tied Transformerless Inverter

    DEFF Research Database (Denmark)

    Ji, Junhao; Wu, Weimin; He, Yuanbin


    The single-phase power converter topologies evolving of photovoltaic applications are still including passive filters, like the LCLor LLCL-filter. Compared with the LCL-filter, the total inductance of the LLCL-filter can be reduced a lot. However, due to the resonant inductor in series with the b......The single-phase power converter topologies evolving of photovoltaic applications are still including passive filters, like the LCLor LLCL-filter. Compared with the LCL-filter, the total inductance of the LLCL-filter can be reduced a lot. However, due to the resonant inductor in series...... with the bypass capacitor, the differential mode (DM) electromagnetic interference (EMI) noise attenuation of an LLCL-filter-based grid-tied inverter declines. Conventionally, a capacitor was inserted in parallel with the LC resonant circuit branch of the LLCL-filter to suppress the DM EMI noise. In order...

  13. Environmental impact case study : Martinsville bypass. (United States)


    At the request of the Environmental Quality Division, the Environmental and Economics Section of the Virginia Highway Research Council conducted an environmental impact study of the proposed Route 220 bypass around Martinsville. This evaluation of th...

  14. Optimal Gaussian Filter for Effective Noise Filtering


    Kopparapu, Sunil; Satish, M


    In this paper we show that the knowledge of noise statistics contaminating a signal can be effectively used to choose an optimal Gaussian filter to eliminate noise. Very specifically, we show that the additive white Gaussian noise (AWGN) contaminating a signal can be filtered best by using a Gaussian filter of specific characteristics. The design of the Gaussian filter bears relationship with the noise statistics and also some basic information about the signal. We first derive a relationship...

  15. Bypass diode for a solar cell (United States)

    Rim, Seung Bum [Palo Alto, CA; Kim, Taeseok [San Jose, CA; Smith, David D [Campbell, CA; Cousins, Peter J [Menlo Park, CA


    Bypass diodes for solar cells are described. In one embodiment, a bypass diode for a solar cell includes a substrate of the solar cell. A first conductive region is disposed above the substrate, the first conductive region of a first conductivity type. A second conductive region is disposed on the first conductive region, the second conductive region of a second conductivity type opposite the first conductivity type.

  16. [Plasma ionized magnesium concentration following cardiopulmonary bypass]. (United States)

    Amaya, Fumimasa; Fukui, Michihiko; Tsuruta, Hiroshi; Kooguchi, Kunihiko; Shimosato, Goshun


    We performed a retrospective study to analyze plasma ionized magnesium concentration following cardiopulmonary bypass. Severe decrease of ionized magnesium concentration associated with frequent abnormal ECG sign was found in a patient with magnesium-free cardioplegia. Cardioplegia containing 16 mmol.l-1 of magnesium ion maintained ionized magnesium concentration within normal ranges without postoperative magnesium loading. Use of cardioplegia containing magnesium or adequate magnesium supplement is thought to be essential for patients receiving cardiopulmonary bypass.

  17. Monsanto may bypass NIH in microbe test. (United States)

    Sun, Marjorie


    The Monsanto Company is planning to ask the Environmental Protection Agency for clearance to field test a genetically engineered microbial pesticide, bypassing the traditional approval process of the National Institutes of Health. Although only federally funded institutions are required to obtain NIH approval for genetic engineering tests, Monsanto is the first company to bypass the NIH regulatory process, which has become mired in a lawsuit brought by Jeremy Rifkin.

  18. Interdigital filter design

    CSIR Research Space (South Africa)

    Du Plessis, WP


    Full Text Available flexible, and allows design tradeoffs to be evaluated in an intuitive way. Keywords: Cavity resonator filters, microwave filters, coupled transmission lines. 1 Introduction Interdigital filters are popular at the higher microwave frequencies for a... number of reasons. Ideal interdigital filters have perfect symmetry which means that they have better phase and delay characteristics than combline filters [1]. The couplings between the resonators of interdigital filters are also lower than those...

  19. [Simplified laparoscopic gastric bypass. Initial experience]. (United States)

    Hernández-Miguelena, Luis; Maldonado-Vázquez, Angélica; Cortes-Romano, Pablo; Ríos-Cruz, Daniel; Marín-Domínguez, Raúl; Castillo-González, Armando


    Obesity surgery includes various gastrointestinal procedures. Roux-en-Y gastric bypass is the prototype of mixed procedures being the most practiced worldwide. A similar and novel technique has been adopted by Dr. Almino Cardoso Ramos and Dr. Manoel Galvao called "simplified bypass," which has been accepted due to the greater ease and very similar results to the conventional technique. The aim of this study is to describe the results of the simplified gastric bypass for treatment of morbid obesity in our institution. We performed a descriptive, retrospective study of all patients undergoing simplified gastric bypass from January 2008 to July 2012 in the obesity clinic of a private hospital in Mexico City. A total of 90 patients diagnosed with morbid obesity underwent simplified gastric bypass. Complications occurred in 10% of patients; these were more frequent bleeding and internal hernia. Mortality in the study period was 0%. The average weight loss at 12 months was 72.7%. Simplified gastric bypass surgery is safe with good mid-term results and a loss of adequate weight in 71% of cases.

  20. Comparative analysis of the selective resonant LCL and LCL plus trap filters

    DEFF Research Database (Denmark)

    Beres, Remus Narcis; Wang, Xiongfei; Blaabjerg, Frede


    is to minimize the damping losses by bypassing the resistor at the fundamental and switching frequencies while preserving high attenuation at higher frequencies. A new design procedure is proposed for the selective resonant LCL filter. The presence of multi-tuned traps in the second topology aims to decrease...... the total size of the filter reactive elements while meeting current harmonic standards. It is found that selective resonant LCL filter provide much lower damping losses compared to the LCL filter with simple resistor topology. Additionally, for the trap topology a minimum switching frequency is determined...

  1. Active Optical Lattice Filters

    Directory of Open Access Journals (Sweden)

    Gary Evans


    Full Text Available Optical lattice filter structures including gains are introduced and analyzed. The photonic realization of the active, adaptive lattice filter is described. The algorithms which map between gains space and filter coefficients space are presented and studied. The sensitivities of filter parameters with respect to gains are derived and calculated. An example which is relevant to adaptive signal processing is also provided.

  2. Polarimetric characterization of birefringent filter components. (United States)

    Mudge, Jason; Mitchell, Keith; Tarbell, Theodore


    Over the past 75 years, birefringent filter technology has evolved significantly. For nearly that same period of time, these filters have been designed and used by solar scientists to study the Sun. Prior to assembling these types of filters, each component, e.g., polarizers and wave plates, is characterized to determine its polarimetric parameters to ensure the desired filter design performance. With time and cost becoming an ever increasing issue, it is imperative to test components designated for a birefringent filter efficiently. This article addresses a shift to increased efficiency when testing components of very low volume (solar research filters that minimizes high-priced hardware expenditures, i.e., Mueller matrix spectropolarimeter.

  3. Filter replacement lifetime prediction (United States)

    Hamann, Hendrik F.; Klein, Levente I.; Manzer, Dennis G.; Marianno, Fernando J.


    Methods and systems for predicting a filter lifetime include building a filter effectiveness history based on contaminant sensor information associated with a filter; determining a rate of filter consumption with a processor based on the filter effectiveness history; and determining a remaining filter lifetime based on the determined rate of filter consumption. Methods and systems for increasing filter economy include measuring contaminants in an internal and an external environment; determining a cost of a corrosion rate increase if unfiltered external air intake is increased for cooling; determining a cost of increased air pressure to filter external air; and if the cost of filtering external air exceeds the cost of the corrosion rate increase, increasing an intake of unfiltered external air.

  4. Managing the inflammatory response after cardiopulmonary bypass: review of the studies in animal models (United States)

    Liguori, Gabriel Romero; Kanas, Alexandre Fligelman; Moreira, Luiz Felipe Pinho


    Objective To review studies performed in animal models that evaluated therapeutic interventions to inflammatory response and microcirculatory changes after cardiopulmonary bypass. Methods It was used the search strategy ("Cardiopulmonary Bypass" (MeSH)) and ("Microcirculation" (MeSH) or "Inflammation" (MeSH) or "Inflammation Mediators" (MeSH)). Repeated results, human studies, non-English language articles, reviews and studies without control were excluded. Results Blood filters, system miniaturization, specific primers regional perfusion, adequate flow and temperature and pharmacological therapies with anticoagulants, vasoactive drugs and anti-inflammatories reduced changes in microcirculation and inflammatory response. Conclusion Demonstrated efficacy in animal models establishes a perspective for evaluating these interventions in clinical practice. PMID:24896169

  5. Percutaneous retrieval of a vena cava filter from the right atrium: case report

    Energy Technology Data Exchange (ETDEWEB)

    Rasuli, P. [The Ottawa Hospital and University of Ottawa, Dept. of Radiology, Ottawa, Ontario (Canada); Mehran, R. [The Ottawa Hospital and University of Ottawa, Dept. of Thoracic Surgery, Ottawa, Ontario (Canada); French, G. [The Ottawa Hospital and University of Ottawa, Dept. of Radiology, Ottawa, Ontario (Canada); Turek, M. [The Ottawa Hospital and University of Ottawa, Dept. of Internal Medicine, Ottawa, Ontario (Canada); Lalonde, K.A. [The Ottawa Hospital and University of Ottawa, Dept. of Thoracic Surgery, Ottawa, Ontario (Canada); Cardinal, P. [The Ottawa Hospital and University of Ottawa, Dept. of Internal Medicine, Ottawa, Ontario (Canada)


    Migration of vena cava filters can occur spontaneously, but it can also occur as a result of entanglement of the filter with a guidewire, particularly during 'blind' (unguided) insertion of a central venous line. When a filter migrates to the heart, traditional practice has been either to leave the filter in place or to remove it surgically by means of open heart surgery and cardiopulmonary bypass. We found only 6 reports of successful percutaneous retrieval or repositioning of a vena cava filter (Table 1). We describe a new interventional technique for retrieving a filter from the right atrium and a novel endosurgical method for removing a filter from the innominate vein. (author)

  6. Efficiency of advanced wastewater treatment technologies for the reduction of hormonal activity in effluents and connected surface water bodies by means of vitellogenin analyses in rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta f. fario). (United States)

    Henneberg, Anja; Triebskorn, Rita


    Endocrine effects in the aquatic environment are in the focus of scientists and media along with debates on the necessity of further steps in wastewater treatment. In the present study VTG responses were compared to evaluate upgrades at wastewater treatment plants (WWTPs). We investigated several advanced sewage treatment technologies at two WWTPs connected to the Schussen, a tributary of Lake Constance, for the reduction of hormonal activity: (1) a powdered activated charcoal filter at the WWTP Langwiese; and (2) a combination of ozonation, sand filter, and granulated activated carbon filter at the WWTP Eriskirch. Rainbow trout and brown trout were either directly exposed to the effluents in aquaria or cages, or in a bypass system flown through by surface water of the Schussen. As a reference, trout were kept in bypass aquaria at the Argen River, which is less influenced by micropollutants. As a biomarker for estrogenicity, we analyzed the yolk precursor protein vitellogenin in immature rainbow trout and brown trout and in trout larvae (100 days post-fertilization) prior to and after the upgrade with the new technologies. Trout of different ages and species were used to detect differences in their sensitivity. At both bypass stations, larvae of brown trout showed significantly higher vitellogenin levels prior to the upgrade compared to negative control levels. Female brown trout exposed at the bypass station downstream of the WWTP showed decreased vitellogenin levels after the upgrade. In 1-year-old immature trout directly exposed to the respective effluents, no significant effects of the upgrades on vitellogenin levels were found. In general, larger effects were observed in brown trout than in rainbow trout, indicating that they are more sensitive test organisms.

  7. Internal Maxillary Bypass for Complex Pediatric Aneurysms. (United States)

    Wang, Long; Lu, Shuaibin; Qian, Hai; Shi, Xiang'en


    Complex pediatric aneurysms (PAs) are an unusual clinicopathologic entity. Data regarding the use of a bypass procedure to treat complex PAs are limited. Internal maxillary artery-to-middle cerebral artery bypass with radial artery graft was used to isolate PAs. Bypass patency and aneurysm stability were evaluated using intraoperative Doppler ultrasound, indocyanine green videoangiography, and postoperative angiography. Modified Rankin Scale was used to assess neurologic function. Over a 5-year period, 7 pediatric patients (≤18 years old) were included in our analysis. Mean age of patients was 14.4 years (range, 12-18 years), and mean size of PAs was 23.6 mm (range, 9-37 mm). All cases manifested with complex characteristics. Proximal artery occlusion was performed in 3 cases, complete excision following aneurysmal distal internal maxillary artery bypass was performed in 2 cases, and combined proximal artery occlusion and aneurysm excision was performed in the 2 remaining cases. Mean intraoperative blood flow was 61.6 mL/minute (range, 40.0-90.8 mL/minute). Graft patency rate was 100% during postoperative recovery and at the last follow-up examination (mean, 20 months; range, 7-45 months). All patients had excellent outcomes except for 1 patient who died of multiple-organ failure. Internal maxillary artery bypass is an essential technique for treatment of selected cases of complex PAs. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Shearing of the plastic coating of a hydrophilic guide wire in a right femoropopliteal bypass graft: removal from the contralateral side. (United States)

    Kemper, F J; Tielbeek, A V; el Biltagiu, S; el Gamal, M I; van Gelder, L M


    The plastic coating of a hydrophilic guide wire tore off during introduction through a beveled single wall arterial entry needle in a 75 year old male. The sheared piece of coating got stuck in his femoropopliteal bypass. It was removed by means of a modified arterial filter set from the contralateral side. The technique of its removal is described.

  9. Application of multi-layer algorithm on image spam filtering (United States)

    Chang, Rui


    This research proposes a three-layer image-spam filtering system. The system filters the image spam by analyzing both the mail header and image. We elaborate the structure of the model and explicate carefully our idea of the design and many technologies related to the model. Experimental results show that this system has satisfactory filtering effect.

  10. Are patients bypassing paediatric cardiology outreach clinics? (United States)

    Fletcher, Alexander; Samson, Ray; McLeod, Karen


    Previous studies have identified that receiving specialist care close to home can positively influence patients' experience. Despite this, a review of cardiology outpatient appointments at the Royal Hospital for Children in Glasgow demonstrated that a large number of families are bypassing their local children's cardiology centre to attend cardiac clinics at the specialist children's surgical centre. We used patient questionnaire, audit of local facilities, and examined the relationship between diagnosis and bypass numbers to better understand factors influencing this trend. Our results suggest that patient preference, short travelling distance to specialist children's cardiac centre, a more severe cardiac diagnosis, and inconsistent local facilities, expertise, and support are likely to influence a family's decision to bypass their local children's cardiology centre.

  11. Doppler spectral characteristics of infrainguinal vein bypasses

    DEFF Research Database (Denmark)

    Nielsen, Tina G; von Jessen, F; Sillesen, H


    of arteriovenous fistulas the initially antegrade diastolic velocity was replaced by a retrograde flow within 3 months, whereas a forward flow in diastole was sustained in grafts with patent fistulas. Abnormal Duplex findings in 31 patients led to angiography and revision in 13 cases. Four revised grafts failed......, while nine remained patent at follow-up 1-12 months later. Ten (56%) of 18 non-revised bypasses with abnormal Duplex findings failed within 9 months compared to 1 (1%) of 76 bypasses with a normal velocity profile (p ... valuable information concerning haemodynamics of infrainguinal vein bypasses and identifies grafts at risk of thrombosis. Inclusion of low resistance index (detection of stenoses appears to improve the sensitivity of Duplex scanning....

  12. A biological oil adsorption filter

    Energy Technology Data Exchange (ETDEWEB)

    Pasila, A. [University of Helsinki (Finland). Dept. of Agricultural Engineering and Household Technology


    A new oil adsorption method called adsorption filtration (AF) has been developed. It is a technology where by oil residues can be cleaned from water by running it through a simple filter made from freeze treated, dried, milled and then fragmented plant material. By choosing suitable plants and fragmentation sizes it is possible to produce filters, which pass water but adsorb oil. The aim of this study was to investigate the possibilities of manufacturing oil adsorbing filter materials from reed canary grass (Phalaris arundinacea), flax (Linum usitatissimum L.) or hemp fibre (Cannabis sativa L.). The oil (80 ml) was mixed with de-ionised water (200 ml) and this mixture was filtered through 10 or 20 g adsorption filters. Fine spring harvested hemp fibre (diameter less than 1 mm) and reed canary grass fragments adsorb 2-4 g of oil per gram of adsorption material compared to 1-3 g of water. Adsorption filtration is thus a novel way of gathering spilled oil in shallow coastal waters before the oil reaches the shore. (author)

  13. Minimally invasive coronary artery bypass grafting: a systematic review. (United States)

    Kikuchi, Keita; Mori, Makoto


    To minimize surgical morbidity in coronary artery bypass grafting, minimally invasive cardiac surgery has gained popularity. Minimally invasive coronary artery bypass grafting offers unique advantages compared to conventional off-pump coronary artery bypass or minimally invasive direct coronary artery bypass in that it enables the surgeon to harvest and graft bilateral internal thoracic arteries via a small thoracotomy while being conducted completely off-pump. This review focuses on current evidence behind off-pump coronary artery bypass, multi-arterial revascularization, patient populations that would most benefit from bilateral internal thoracic artery minimally invasive coronary artery bypass grafting, the surgical technique, and early outcomes. By overcoming the perceived inability to utilize bilateral internal thoracic arteries in minimally invasive coronary artery bypass grafting, the new technique further expands the armamentarium of surgeons and cardiologists. Hybrid coronary revascularization with bilateral internal thoracic artery minimally invasive coronary artery bypass grafting further augments the appeal of the next generation of minimally invasive cardiac surgery.

  14. Gastric Bypass Surgery: What Happens If I Regain the Weight? (United States)

    ... happens if you gain back weight after gastric bypass surgery? Answers from Katherine Zeratsky, R.D., L. ... If you begin to regain weight after gastric bypass surgery, talk to your doctor. You may have ...

  15. Analgesic Treatment in Laparoscopic Gastric Bypass Surgery

    DEFF Research Database (Denmark)

    Andersen, Lars P H; Werner, Mads U; Rosenberg, Jacob


    This review aimed to present an overview of the randomized controlled trials investigating analgesic regimens used in laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery. Literature search was performed in PubMed and EMBASE databases in August 2013 in accordance to PRISMA guidelines. The litera......This review aimed to present an overview of the randomized controlled trials investigating analgesic regimens used in laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery. Literature search was performed in PubMed and EMBASE databases in August 2013 in accordance to PRISMA guidelines...

  16. Sensory Pollution from Bag Filters, Carbon Filters and Combinations

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Clausen, Geo; Weschler, Charles J.


    by an upstream pre-filter (changed monthly), an EU7 filter protected by an upstream activated carbon (AC) filter, and EU7 filters with an AC filter either downstream or both upstream and downstream. In addition, two types of stand-alone combination filters were evaluated: a bag-type fiberglass filter...


    Energy Technology Data Exchange (ETDEWEB)

    John Erjavec; Michael D. Mann; Ryan Z. Knutson; Michael L. Swanson; Michael E. Collings


    This work was performed through the University of North Dakota (UND) Chemical Engineering Department with assistance from UND's Energy & Environmental Research Center. This research was undertaken in response to the U.S. Department of Energy Federal Technology Center Program Solicitation No. DE-PS26-99FT40479, Support of Advanced Coal Research at U.S. Universities and Colleges. Specifically, this research was in support of the UCR Core Program and addressees Topic 1, Improved Hot-Gas Contaminant and Particulate Removal Techniques, introducing an advanced design for particulate removal. Integrated gasification combined cycle (IGCC) offers the potential for very high efficiency and clean electric generation. In IGCC, the product gas from the gasifier needs to be cleaned of particulate matter to avoid erosion and high-temperature corrosion difficulties arising with the turbine blades. Current methods involve cooling the gases to {approx}100 C to condense alkalis and remove sulfur and particulates using conventional scrubber technology. This ''cool'' gas is then directed to a turbine for electric generation. While IGCC has the potential to reach efficiencies of over 50%, the current need to cool the product gas for cleaning prior to firing it in a turbine is keeping IGCC from reaching its full potential. The objective of the current project was to develop a highly reliable particulate collector system that can meet the most stringent turbine requirements and emission standards, can operate at temperatures above 1500 F, is applicable for use with all U.S. coals, is compatible with various sorbent injection schemes for sulfur and alkali control, can be integrated into a variety of configurations for both pressurized gasification and combustion, increases allowable face velocity to reduce filter system capital cost, and is cost-competitive with existing technologies. The collector being developed is a new concept in particulate control called

  18. 21 CFR 870.4240 - Cardiopulmonary bypass heat exchanger. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass heat exchanger. 870.4240... bypass heat exchanger. (a) Identification. A cardiopulmonary bypass heat exchanger is a device, consisting of a heat exchange system used in extracorporeal circulation to warm or cool the blood or...

  19. 21 CFR 870.4230 - Cardiopulmonary bypass defoamer. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass defoamer. 870.4230 Section... bypass defoamer. (a) Identification. A cardiopulmonary bypass defoamer is a device used in conjunction... entitled “Guidance for Extracorporeal Blood Circuit Defoamer 510(k) Submissions.” [45 FR 7907-7971, Feb. 5...

  20. 21 CFR 870.4250 - Cardiopulmonary bypass temperature controller. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass temperature controller. 870... Cardiopulmonary bypass temperature controller. (a) Identification. A cardiopulmonary bypass temperature controller is a device used to control the temperature of the fluid entering and leaving a heat exchanger. (b...

  1. 21 CFR 870.4400 - Cardiopulmonary bypass blood reservoir. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass blood reservoir. 870.4400... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Surgical Devices § 870.4400 Cardiopulmonary bypass blood reservoir. (a) Identification. A cardiopulmonary bypass blood reservoir is a device used in...

  2. 21 CFR 870.4300 - Cardiopulmonary bypass gas control unit. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass gas control unit. 870.4300... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Surgical Devices § 870.4300 Cardiopulmonary bypass gas control unit. (a) Identification. A cardiopulmonary bypass gas control unit is a device used...

  3. 21 CFR 870.4430 - Cardiopulmonary bypass intracardiac suction control. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass intracardiac suction....4430 Cardiopulmonary bypass intracardiac suction control. (a) Identification. A cardiopulmonary bypass intracardiac suction control is a device which provides the vacuum and control for a cardiotomy return sucker...

  4. Outcomes after off-pump coronary bypass surgery

    NARCIS (Netherlands)

    Dijk, Diederik van


    The complications associated with in coronary artery bypass surgery (CABG) using cardiopulmonary bypass (CPB) have led to a renewed interest in coronary bypass surgery on the beating heart. The primary objective of the Octopus Study was to compare cognitive outcome between patients randomized to

  5. A statistical rain attenuation prediction model with application to the advanced communication technology satellite project. 3: A stochastic rain fade control algorithm for satellite link power via non linear Markow filtering theory (United States)

    Manning, Robert M.


    The dynamic and composite nature of propagation impairments that are incurred on Earth-space communications links at frequencies in and above 30/20 GHz Ka band, i.e., rain attenuation, cloud and/or clear air scintillation, etc., combined with the need to counter such degradations after the small link margins have been exceeded, necessitate the use of dynamic statistical identification and prediction processing of the fading signal in order to optimally estimate and predict the levels of each of the deleterious attenuation components. Such requirements are being met in NASA's Advanced Communications Technology Satellite (ACTS) Project by the implementation of optimal processing schemes derived through the use of the Rain Attenuation Prediction Model and nonlinear Markov filtering theory.

  6. Outcomes of combined trabecular micro-bypass and phacoemulsification in a predominantly Hispanic patient population

    Directory of Open Access Journals (Sweden)

    Gallardo MJ


    in IOP for Groups 2 and 3, were highly statistically significant (P<0.001. Two eyes in Group 3 had filtering surgery; the remaining 95% avoided such treatment. No other complications were reported.Conclusion: This mainly Hispanic population with predominantly moderate or severe glaucoma had substantial reduction of IOP and medication and favorable safety for 12 months following stent implantation during cataract surgery, with treatment success achieved in all 3 subgroups. These data show this stent technology to be effective in Hispanic eyes with more advanced disease. Keywords: glaucoma, trabecular micro-bypass, Hispanic, micro-invasive glaucoma surgery, IOP

  7. In Defense of Filtering. (United States)

    Burt, David


    Presents responses to 10 common arguments against the use of Internet filters in libraries. Highlights include keyword blocking; selection of materials; liability of libraries using filters; users' judgments; Constitutional issues, including First Amendment rights; and censorship. (LRW)

  8. Robotically-Assisted Coronary Artery Bypass Grafting

    Directory of Open Access Journals (Sweden)

    Thierry A. Folliguet


    Full Text Available Objectives. Robotic surgery enables to perform coronary surgery totally endoscopically. This report describes our experience using the da Vinci system for coronary artery bypass surgery. Methods. Patients requiring single-or-double vessel revascularization were eligible. The procedure was performed without cardiopulmonary bypass on a beating heart. Results. From April 2004 to May 2008, fifty-six patients were enrolled in the study. Twenty-four patients underwent robotic harvesting of the mammary conduit followed by minimal invasive direct coronary artery bypass (MIDCAB, and twenty-three patients had a totally endoscopic coronary artery bypass (TECAB grafting. Nine patients (16% were converted to open techniques. The mean total operating time for TECAB was 372±104 minutes and for MIDCAB was 220±69 minutes. Followup was complete for all patients up to one year. There was one hospital death following MIDCAB and two deaths at follow up. Forty-eight patients had an angiogram or CT scan revealing occlusion or anastomotic stenoses (>50% in 6 patients. Overall permeability was 92%. Conclusions. Robotic surgery can be performed with promising results.

  9. Bypassing BDD Construction for Reliability Analysis

    DEFF Research Database (Denmark)

    Williams, Poul Frederick; Nikolskaia, Macha; Rauzy, Antoine


    In this note, we propose a Boolean Expression Diagram (BED)-based algorithm to compute the minimal p-cuts of boolean reliability models such as fault trees. BEDs make it possible to bypass the Binary Decision Diagram (BDD) construction, which is the main cost of fault tree assessment....

  10. Planetary science: Bypassing the habitable zone (United States)

    Ingersoll, Andrew P.


    In our own solar system, Venus is too hot, Mars is too cold and Earth is just right. Simulations show that making an icy planet habitable is not as simple as melting its ice: many icy bodies swing from too cold to too hot, bypassing just right.

  11. A Survey of Cache Bypassing Techniques

    Directory of Open Access Journals (Sweden)

    Sparsh Mittal


    Full Text Available With increasing core-count, the cache demand of modern processors has also increased. However, due to strict area/power budgets and presence of poor data-locality workloads, blindly scaling cache capacity is both infeasible and ineffective. Cache bypassing is a promising technique to increase effective cache capacity without incurring power/area costs of a larger sized cache. However, injudicious use of cache bypassing can lead to bandwidth congestion and increased miss-rate and hence, intelligent techniques are required to harness its full potential. This paper presents a survey of cache bypassing techniques for CPUs, GPUs and CPU-GPU heterogeneous systems, and for caches designed with SRAM, non-volatile memory (NVM and die-stacked DRAM. By classifying the techniques based on key parameters, it underscores their differences and similarities. We hope that this paper will provide insights into cache bypassing techniques and associated tradeoffs and will be useful for computer architects, system designers and other researchers.

  12. MST Filterability Tests

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Duignan, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The low filter flux through the ARP has limited the rate at which radioactive liquid waste can be treated. Recent filter flux has averaged approximately 5 gallons per minute (gpm). Salt Batch 6 has had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. In addition, at the time the testing started, SRR was assessing the impact of replacing the 0.1 micron filter with a 0.5 micron filter. This report describes testing of MST filterability to investigate the impact of filter pore size and MST particle size on filter flux and testing of filter enhancers to attempt to increase filter flux. The authors constructed a laboratory-scale crossflow filter apparatus with two crossflow filters operating in parallel. One filter was a 0.1 micron Mott sintered SS filter and the other was a 0.5 micron Mott sintered SS filter. The authors also constructed a dead-end filtration apparatus to conduct screening tests with potential filter aids and body feeds, referred to as filter enhancers. The original baseline for ARP was 5.6 M sodium salt solution with a free hydroxide concentration of approximately 1.7 M.3 ARP has been operating with a sodium concentration of approximately 6.4 M and a free hydroxide concentration of approximately 2.5 M. SRNL conducted tests varying the concentration of sodium and free hydroxide to determine whether those changes had a significant effect on filter flux. The feed slurries for the MST filterability tests were composed of simple salts (NaOH, NaNO2, and NaNO3) and MST (0.2 – 4.8 g/L). The feed slurry for the filter enhancer tests contained simulated salt batch 6 supernate, MST, and filter enhancers.

  13. Post-Bypass Extensive Ascites due to Splanchnic Bypass and the Effectiveness of Hyperalimentation Treatment

    Directory of Open Access Journals (Sweden)

    Veysel Temizkan


    Full Text Available Reperfusion edema may develop in the early periods of chronic ischemic tissue reperfusion. Reperfusion edema may be represented after the splanchnic bypass with ascites, abdominal distension, and liver and kidney function impairment. In this article, we are reporting the hyperalimentation treatment and its results for the common ascites and hepatorenal syndrome, after a coeliac and superior mesenteric artery bypass. [Arch Clin Exp Surg 2013; 2(2.000: 124-128

  14. Comparison between analog and digital filters

    Directory of Open Access Journals (Sweden)

    Zoltan Erdei


    Full Text Available Digital signal processing(DSP is one of the most powerful technologies and will model science and engineering in the 21st century. Revolutionary changes have already been made in different areas of research such as communications, medical imaging, radar and sonar technology, high fidelity audio signal reproducing etc. Each of these fields developed a different signal processing technology with its own algorithms, mathematics and technology, Digital filters are used in two general directions: to separate mixed signals and to restore signals that were compromised in different modes. The objective of this paper is to compare some basic digital filters versus analog filters such as low-pass, high-pass, band-pass filters. Scientists and engineers comprehend that, in comparison with analog filters, digital filters can process the same signal in real-time with broader flexibility. This understanding is considered important to instill incentive for engineers to become interested in the field of DSP. The analysis of the results will be made using dedicated libraries in MATLAB and Simulink software, such as the Signal Processing Toolbox.

  15. Oriented Fiber Filter Media


    R. Bharadwaj; A. Patel, S. Chokdeepanich, Ph.D.; G.G. Chase, Ph.D.


    Coalescing filters are widely used throughout industry and improved performance will reduce droplet emissions and operating costs. Experimental observations show orientation of micro fibers in filter media effect the permeability and the separation efficiency of the filter media. In this work two methods are used to align the fibers to alter the filter structure. The results show that axially aligned fiber media improve quality factor on the order of 20% and cutting media on an angle from a t...

  16. Filter service system (United States)

    Sellers, Cheryl L [Peoria, IL; Nordyke, Daniel S [Arlington Heights, IL; Crandell, Richard A [Morton, IL; Tomlins, Gregory [Peoria, IL; Fei, Dong [Peoria, IL; Panov, Alexander [Dunlap, IL; Lane, William H [Chillicothe, IL; Habeger, Craig F [Chillicothe, IL


    According to an exemplary embodiment of the present disclosure, a system for removing matter from a filtering device includes a gas pressurization assembly. An element of the assembly is removably attachable to a first orifice of the filtering device. The system also includes a vacuum source fluidly connected to a second orifice of the filtering device.

  17. Bias aware Kalman filters

    DEFF Research Database (Denmark)

    Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan


    This paper reviews two different approaches that have been proposed to tackle the problems of model bias with the Kalman filter: the use of a colored noise model and the implementation of a separate bias filter. Both filters are implemented with and without feedback of the bias into the model sta...

  18. HEPA filter encapsulation (United States)

    Gates-Anderson, Dianne D.; Kidd, Scott D.; Bowers, John S.; Attebery, Ronald W.


    A low viscosity resin is delivered into a spent HEPA filter or other waste. The resin is introduced into the filter or other waste using a vacuum to assist in the mass transfer of the resin through the filter media or other waste.

  19. Kalman filter applied in underwater integrated navigation system

    Directory of Open Access Journals (Sweden)

    Yan Xincun


    Full Text Available For the underwater integrated navigation system, information fusion is an important technology. This paper introduces the Kalman filter as the most useful information fusion technology, and then gives a summary of the Kalman filter applied in underwater integrated navigation system at present, and points out the further research directions in this field.

  20. Regenerative particulate filter development (United States)

    Descamp, V. A.; Boex, M. W.; Hussey, M. W.; Larson, T. P.


    Development, design, and fabrication of a prototype filter regeneration unit for regenerating clean fluid particle filter elements by using a backflush/jet impingement technique are reported. Development tests were also conducted on a vortex particle separator designed for use in zero gravity environment. A maintainable filter was designed, fabricated and tested that allows filter element replacement without any leakage or spillage of system fluid. Also described are spacecraft fluid system design and filter maintenance techniques with respect to inflight maintenance for the space shuttle and space station.

  1. Concomitant aorto-right subclavian artery bypass with off-pump coronary artery bypass grafting: a case report. (United States)

    Tazume, Hirokazu; Okamoto, Ken; Fukui, Toshihiro


    Atherosclerotic stenosis of the brachiocephalic artery sometimes occurs in patients with coronary artery disease, and can cause stroke during the perioperative period of coronary artery bypass grafting. We describe the case of a 77-year old male with severe stenosis of the brachiocephalic artery and severe coronary artery disease. He successfully underwent aorto-right subclavian artery bypass that was performed concomitantly with off-pump coronary artery bypass. Concomitant aorto-subclavian artery bypass with off-pump coronary artery bypass grafting is a therapeutic option that minimizes the risk of perioperative stroke in patients with brachiocephalic artery stenosis and coronary artery disease.

  2. SUrgical versus PERcutaneous Bypass : SUPERB-trial; Heparin-bonded endoluminal versus surgical femoro-popliteal bypass: study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Lensvelt, Mare M. A.; Holewijn, Suzanne; Fritschy, Wilbert M.; Wikkeling, Otmar R. M.; van Walraven, Laurens A.; de Vries, Bas M. Wallis; Zeebregts, Clark J.; Reijnen, Michel M. P. J.


    Background: Endovascular treatment options for the superficial femoral artery are evolving rapidly. For long lesions, the venous femoropopliteal bypass considered to be superior above the prosthetic bypass. An endoluminal bypass, however, may provide equal patency rates compared to the prosthetic

  3. SUrgical versus PERcutaneous Bypass: SUPERB-trial; Heparin-bonded endoluminal versus surgical femoro-popliteal bypass: study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Lensvelt, M.M.A.; Holewijn, S.; Fritschy, W.M.; Wikkeling, O.R.; Walraven, L.A. van; Wallis de Vries, B.M.; Zeebregts, C.J.A.; Reijnen, M.M.P.J.


    BACKGROUND: Endovascular treatment options for the superficial femoral artery are evolving rapidly. For long lesions, the venous femoropopliteal bypass considered to be superior above the prosthetic bypass. An endoluminal bypass, however, may provide equal patency rates compared to the prosthetic

  4. Voltage Mode Single CDBA Based Multifunction Filter (United States)

    Gupta, Priyanka; Pandey, Rajeshwari; Pandey, Neeta


    A voltage mode multifunction second order filter topology employing single current differencing buffered amplifier (CDBA) has been proposed in this paper. This topology can be used to synthesize low pass (LP), band pass (BP), and high pass (HP) filter functions with appropriate admittance choices. This configuration is a suitable choice for implementing filters with high quality factor. The demonstration of the proposed configuration is done through PSPICE simulations. The CDBA block is realized using CMOS 0.18µm technology. The simulation results are found in close agreement with the theoretical results.

  5. Vacuum-assisted drainage in cardiopulmonary bypass: advantages and disadvantages (United States)

    de Carvalho Filho, Élio Barreto; Marson, Fernando Augusto de Lima; da Costa, Loredana Nilkenes Gomes; Antunes, Nilson


    Systematic review of vacuum assisted drainage in cardiopulmonary bypass, demonstrating its advantages and disadvantages, by case reports and evidence about its effects on microcirculation. We conducted a systematic search on the period 1997-2012, in the databases PubMed, Medline, Lilacs and SciELO. Of the 70 selected articles, 26 were included in the review. Although the vacuum assisted drainage has significant potential for complications and requires appropriate technology and professionalism, prevailed in literature reviewed the concept that vacuum assisted drainage contributed in reducing the rate of transfusions, hemodilutions, better operative field, no significant increase in hemolysis, reduced complications surgical, use of lower prime and of smaller diameter cannulas. PMID:25140478

  6. No ethical bypass of moral status in stem cell research. (United States)

    Brown, Mark


    Recent advances in reprogramming technology do not bypass the ethical challenge of embryo sacrifice. Induced pluripotent stem cell (iPS) research has been and almost certainly will continue to be conducted within the context of embryo sacrifice. If human embryos have moral status as human beings, then participation in iPS research renders one morally complicit in their destruction; if human embryos have moral status as mere precursors of human beings, then advocacy of iPS research policy that is inhibited by embryo sacrifice concerns renders one morally complicit in avoidable harms to persons. Steps may be taken to address these complicity concerns, but in the final analysis there is no alternative to achieving clarity with respect to the moral status of the human embryo. © 2011 Blackwell Publishing Ltd.

  7. Membrane filter technologies for safe and clean processes and improved production; Filtrazione. Sicurezza, igiene, migliore produzione. Esperienze e proposte dalla Francia

    Energy Technology Data Exchange (ETDEWEB)

    Mezzalira, P. (comp.)


    A wide variety of separation technologies, from membrane filtration, to chromatography, from reverse osmosis to micro- and ultrafiltration, with state-of-the-art tools are employed in various sectors to optimise process safety and improve production. The expertise and know-how of some companies in France. [Italian] Diverse tecnologie di filtrazione, dalla separazione a membrana, alla cromatografia, dall'osmosi inversa alla micro e ultrafiltrazione con apparecchiature d'avanguardia continuamente aggiornate, per le svariate applicazioni in diversi settori di attivita', all'insegna della sicurezza, dell'igiene, e di una migliore produttivita'.

  8. Virtual nonenhanced dual-energy CT urography with tin-filter technology: determinants of detection of urinary calculi in the renal collecting system. (United States)

    Mangold, Stefanie; Thomas, Christoph; Fenchel, Michael; Vuust, Morten; Krauss, Bernhard; Ketelsen, Dominik; Tsiflikas, Ilias; Claussen, Claus D; Heuschmid, Martin


    To retrospectively determine which features of urinary calculi are associated with their detection after virtual elimination of contrast medium at dual-energy computed tomographic (CT) urography by using a novel tin filter. The institutional ethics committee approved this retrospective study, with waiver of informed consent. A total of 152 patients were examined with single-energy nonenhanced CT and dual-energy CT urography in the excretory phase (either 140 and 80 kV [n=44] or 140 and 100 kV [n=108], with tin filtration at 140 kV). The contrast medium in the renal pelvis and ureters was virtually removed from excretory phase images by using postprocessing software, resulting in virtual nonenhanced (VNE) images. The sensitivity regarding the detection of calculi on VNE images compared with true nonenhanced (TNE) images was determined, and interrater agreement was evaluated by using the Cohen k test. By using logistic regression, the influences of image noise, attenuation, and stone size, as well as attenuation of the contrast medium, on the stone detection rate were assessed. Threshold values with maximal sensitivity and specificity were calculated by means of receiver operating characteristic analyses. Eighty-seven stones were detected on TNE images; 46 calculi were identified on VNE images (sensitivity, 52.9%). Interrater agreement revealed a κ value of 0.95 with TNE images and 0.91 with VNE data. Size (long-axis diameter, P=.005; short-axis diameter, P=.041) and attenuation (P=.0005) of the calculi and image noise (P=.0031) were significantly associated with the detection rate on VNE images. As threshold values, size larger than 2.9 mm, maximum attenuation of the calculi greater than 387 HU, and image noise less than 20 HU were found. After virtual elimination of contrast medium, large (>2.9 mm) and high-attenuation (>387 HU) calculi can be detected with good reliability; smaller and lower attenuation calculi might be erased from images, especially with

  9. Progress on applications of high temperature superconducting microwave filters (United States)

    Chunguang, Li; Xu, Wang; Jia, Wang; Liang, Sun; Yusheng, He


    In the past two decades, various kinds of high performance high temperature superconducting (HTS) filters have been constructed and the HTS filters and their front-end subsystems have been successfully applied in many fields. The HTS filters with small insertion loss, narrow bandwidth, flat in-band group delay, deep out-of-band rejection, and steep skirt slope are reviewed. Novel HTS filter design technologies, including those in high power handling filters, multiband filters and frequency tunable filters, are reviewed, as well as the all-HTS integrated front-end receivers. The successful applications to various civilian fields, such as mobile communication, radar, deep space detection, and satellite technology, are also reviewed.

  10. Compact planar microwave blocking filters (United States)

    U-Yen, Kongpop (Inventor); Wollack, Edward J. (Inventor)


    A compact planar microwave blocking filter includes a dielectric substrate and a plurality of filter unit elements disposed on the substrate. The filter unit elements are interconnected in a symmetrical series cascade with filter unit elements being organized in the series based on physical size. In the filter, a first filter unit element of the plurality of filter unit elements includes a low impedance open-ended line configured to reduce the shunt capacitance of the filter.

  11. FILTSoft: A computational tool for microstrip planar filter design (United States)

    Elsayed, M. H.; Abidin, Z. Z.; Dahlan, S. H.; Cholan N., A.; Ngu, Xavier T. I.; Majid, H. A.


    Filters are key component of any communication system to control spectrum and suppress interferences. Designing a filter involves long process as well as good understanding of the basic hardware technology. Hence this paper introduces an automated design tool based on Matlab-GUI, called the FILTSoft (acronym for Filter Design Software) to ease the process. FILTSoft is a user friendly filter design tool to aid, guide and expedite calculations from lumped elements level to microstrip structure. Users just have to provide the required filter specifications as well as the material description. FILTSoft will calculate and display the lumped element details, the planar filter structure, and the expected filter's response. An example of a lowpass filter design was calculated using FILTSoft and the results were validated through prototype measurement for comparison purposes.

  12. The diffuse ensemble filter

    Directory of Open Access Journals (Sweden)

    X. Yang


    Full Text Available A new class of ensemble filters, called the Diffuse Ensemble Filter (DEnF, is proposed in this paper. The DEnF assumes that the forecast errors orthogonal to the first guess ensemble are uncorrelated with the latter ensemble and have infinite variance. The assumption of infinite variance corresponds to the limit of "complete lack of knowledge" and differs dramatically from the implicit assumption made in most other ensemble filters, which is that the forecast errors orthogonal to the first guess ensemble have vanishing errors. The DEnF is independent of the detailed covariances assumed in the space orthogonal to the ensemble space, and reduces to conventional ensemble square root filters when the number of ensembles exceeds the model dimension. The DEnF is well defined only in data rich regimes and involves the inversion of relatively large matrices, although this barrier might be circumvented by variational methods. Two algorithms for solving the DEnF, namely the Diffuse Ensemble Kalman Filter (DEnKF and the Diffuse Ensemble Transform Kalman Filter (DETKF, are proposed and found to give comparable results. These filters generally converge to the traditional EnKF and ETKF, respectively, when the ensemble size exceeds the model dimension. Numerical experiments demonstrate that the DEnF eliminates filter collapse, which occurs in ensemble Kalman filters for small ensemble sizes. Also, the use of the DEnF to initialize a conventional square root filter dramatically accelerates the spin-up time for convergence. However, in a perfect model scenario, the DEnF produces larger errors than ensemble square root filters that have covariance localization and inflation. For imperfect forecast models, the DEnF produces smaller errors than the ensemble square root filter with inflation. These experiments suggest that the DEnF has some advantages relative to the ensemble square root filters in the regime of small ensemble size, imperfect model, and copious

  13. Generic Kalman Filter Software (United States)

    Lisano, Michael E., II; Crues, Edwin Z.


    The Generic Kalman Filter (GKF) software provides a standard basis for the development of application-specific Kalman-filter programs. Historically, Kalman filters have been implemented by customized programs that must be written, coded, and debugged anew for each unique application, then tested and tuned with simulated or actual measurement data. Total development times for typical Kalman-filter application programs have ranged from months to weeks. The GKF software can simplify the development process and reduce the development time by eliminating the need to re-create the fundamental implementation of the Kalman filter for each new application. The GKF software is written in the ANSI C programming language. It contains a generic Kalman-filter-development directory that, in turn, contains a code for a generic Kalman filter function; more specifically, it contains a generically designed and generically coded implementation of linear, linearized, and extended Kalman filtering algorithms, including algorithms for state- and covariance-update and -propagation functions. The mathematical theory that underlies the algorithms is well known and has been reported extensively in the open technical literature. Also contained in the directory are a header file that defines generic Kalman-filter data structures and prototype functions and template versions of application-specific subfunction and calling navigation/estimation routine code and headers. Once the user has provided a calling routine and the required application-specific subfunctions, the application-specific Kalman-filter software can be compiled and executed immediately. During execution, the generic Kalman-filter function is called from a higher-level navigation or estimation routine that preprocesses measurement data and post-processes output data. The generic Kalman-filter function uses the aforementioned data structures and five implementation- specific subfunctions, which have been developed by the user on

  14. High-performance analysis of filtered semantic graphs

    Energy Technology Data Exchange (ETDEWEB)

    Buluc, Aydin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fox, Armando [Univ. of California, Berkeley, CA (United States); Gilbert, John R. [Univ. of California, Santa Barbara, CA (United States); Kamil, Shoaib A. [Univ. of California, Berkeley, CA (United States); Lugowski, Adam [Univ. of California, Santa Barbara, CA (United States); Oliker, Leonid [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Williams, Samuel W. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)


    High performance is a crucial consideration when executing a complex analytic query on a massive semantic graph. In a semantic graph, vertices and edges carry "attributes" of various types. Analytic queries on semantic graphs typically depend on the values of these attributes; thus, the computation must either view the graph through a filter that passes only those individual vertices and edges of interest, or else must first materialize a subgraph or subgraphs consisting of only the vertices and edges of interest. The filtered approach is superior due to its generality, ease of use, and memory efficiency, but may carry a performance cost. In the Knowledge Discovery Toolbox (KDT), a Python library for parallel graph computations, the user writes filters in a high-level language, but those filters result in relatively low performance due to the bottleneck of having to call into the Python interpreter for each edge. In this work, we use the Selective Embedded JIT Specialization (SEJITS) approach to automatically translate filters defined by programmers into a lower-level efficiency language, bypassing the upcall into Python. We evaluate our approach by comparing it with the high-performance C++ /MPI Combinatorial BLAS engine, and show that the productivity gained by using a high-level filtering language comes without sacrificing performance.

  15. [Robot-assisted Coronary Artery Bypass Grafting]. (United States)

    Ishikawa, Norihiko; Watanabe, Go


    The application for robot-assisted coronary surgery ranges from internal thoracic artery (ITA) harvesting with hand-sewn anastomoses to totally endoscopic coronary artery bypass grafting (TECAB), either on- or off-pump. The bilateral IMA can be harvested with the aid of a surgical robot and then multivessel bypass grafting can follow. Such robot-assisted minimally invasive direct coronary artery bypass grafting is called "ThoraCAB". Surgical robots cannot only endoscopically harvest the ITA but they can also anastomose the coronary artery in TECAB. But TECAB still has the difficulties, such as narrow surgical field in Japanese patients. Both procedures have the significant advantages of minimizing surgical trauma, such as reduced comlications, faster return back to normal activities and being improved cosmesis, and which have resulted in the development of minimally invasive surgery. Robot-assisted cardiac surgery for structural heart disease has been approved by the Ministry of Health, Labour and Welfare (MHLW) since December 2015, however, robot-assisted cardiac surgery for TECAB has not been approved yet in Japan.

  16. Steam by-pass reciprocating rod pump

    Energy Technology Data Exchange (ETDEWEB)

    Waterhouse, B. [Weatherford, Edmonton, AB (Canada)


    This article presented the design details of Weatherford's steam by-pass reciprocating rod rod pump which was designed to work under specific well conditions and individual applications, including Imperial Oil's Cold Lake bitumen recovery project located 230 km northeast of Edmonton, Alberta. Imperial Oil uses a cyclic steam stimulation (CSS) process to enhance bitumen recovery from the Clearwater oil sand reservoir. A typical wellbore reach can be up to 700 m and 80 degrees deviation at a target depth of 455 m TVD. These long well bore reaches along with high bottomhole angles and high produced fluid viscosities complicate the design of the artificial lift, which is essentially a modified conventional API pump. The hold-down section is a friction ring design incorporating stainless steel friction rings to provide positive holding force. The steam by-pass coupling is a reduced-diameter tube fitting between the API pump and the friction ring hold-down section. Three stages of the Imperial Cold Lake operation were described, namely the steam injection stage, soak phase stage and production stage. Typically, the steam by-pass pump is suspended in the tubing for the entire cycle. This presentation reviewed the operating steps of the pump, whose average run time in the field is about 15 months, depending on the potential for scaling or sand influx. tab., figs.

  17. Patient's Perception About Coronary Artery Bypass Grafting

    Directory of Open Access Journals (Sweden)

    Kelminda Maria Bulhões Mendonça


    Full Text Available ABSTRACT OBJECTIVE: The diagnosis of coronary artery disease referred for heart surgery has an important psychological component. The purpose of this study was to access the difficulties experienced by individuals awaiting coronary artery bypass grafting and to determine strategies that facilitate adaptation to a new lifestyle, modified by the disease. METHODS: A qualitative, exploratory study involving patients admitted to a university teaching hospital in the city of Salvador, Bahia, Brazil, awaiting coronary artery bypass grafting. Semi-structured interviews were performed in accordance with a previously defined script based on the study objective. Each transcription was read in its entirety to verify the representativeness, homogeneity and pertinence of the data obtained (pre-analysis, followed by separation of categories of analysis. RESULTS: The descriptions of this study show that patients admitted to the completion of coronary artery bypass grafting experience a wide range of psychological difficulties, considering that surgery acquires interpretations that vary according to individuals' subjectivity. The patients recognized the benefit of being able to discuss their feelings as a means of diminishing their fear and anxiety. CONCLUSION: Helping patients find resources to confront more positively the daily hospitalization is an important aspect for the health care professionals who assist them. This goal can be achieved through modification of the biomedical model of care for a biopsychosocial view. The investment of time and attention is of fundamental importance and aims to overcome existing deficiencies that interfere with the outcome of patients after cardiac surgery.

  18. Totally Robotic Reversal of Omega-Loop Gastric Bypass to Normal Anatomy. (United States)

    Reche, Fabian; Mancini, Adrian; Borel, Anne-Laure; Faucheron, Jean-Luc


    using the DaVinci Si™ system by Intuitive Surgical Inc ®, Sunnyvale, CA. In this high definition video, we present step-by-step robotic reversal of the omega-loop gastric bypass. The procedure began with a careful adhesiolysis of the left lobe of the liver, small gastric pouch, and omega-loop. Then, the gastro-jejunostomy was transected with a 45-mm Endo GIA endocutter with purple staples. The key-point was the creation of a gastro-gastric anastomosis between the small gastric pouch and the excluded stomach. Omega-loop jejunum was resected and the anastomosis was performed in order to avoid intestinal stenosis. The operative time was 232 min. Postoperative course was uneventful and the patient was discharged in postoperative day 8. One month after the procedure, she has gained 10 kg (albumin 34 g/l) and stabilized her nutritional status without further nutritional support. This is the first case described in the literature of a reversal omega-loop gastric bypass into normal anatomy and the first description of the use of a robotic approach. This intervention is challenging, but a feasible procedure. This technology may increase the number of surgeons who are able to provide the benefits of minimal invasive surgery to their patients without the increased risks of complications associated with initial learning curves. The three-dimensional robotic vision, a stable camera, and the multiples degrees of freedom of the robotic instruments are the features that seem to provide greater surgical precision for these complex laparoscopic operations.

  19. High water quality without chemical additives. Filter system for decentral systems; Hohe Wasserqualitaet durch chemikalienfreie Gesamtloesung. Filtersystem fuer dezentrale Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Barth, Christain [Enwa AS Deutschland, Bonn (Germany)


    District heating, with its many heat transfer stations, makes high demands on the water quality of the system fluid. In order to ensure efficient heat transfer and uninterrupted operation, Enwa-Matic bypass filters were installed in two biogas plants. They filter particulate matter out of the system and purify the plant water without chemical additives, so that corrosion protection is ensured by a self-regulating pH.

  20. Spot- Zombie Filtering System


    Arathy Rajagopal; B. Geethanjali; Arulprakash P


    A major security challenge on the Internet is the existence of the large number of compromised machines. Such machines have been increasingly used to launch various security attacks including spamming and spreading malware, DDoS, and identity theft. These compromised machines are called "Zombies". In general E-mail applications and providers uses spam filters to filter the spam messages. Spam filtering is a technique for discriminating the genuine message from the spam messages. The attackers...

  1. Hybrid Filter Membrane (United States)

    Laicer, Castro; Rasimick, Brian; Green, Zachary


    Cabin environmental control is an important issue for a successful Moon mission. Due to the unique environment of the Moon, lunar dust control is one of the main problems that significantly diminishes the air quality inside spacecraft cabins. Therefore, this innovation was motivated by NASA s need to minimize the negative health impact that air-suspended lunar dust particles have on astronauts in spacecraft cabins. It is based on fabrication of a hybrid filter comprising nanofiber nonwoven layers coated on porous polymer membranes with uniform cylindrical pores. This design results in a high-efficiency gas particulate filter with low pressure drop and the ability to be easily regenerated to restore filtration performance. A hybrid filter was developed consisting of a porous membrane with uniform, micron-sized, cylindrical pore channels coated with a thin nanofiber layer. Compared to conventional filter media such as a high-efficiency particulate air (HEPA) filter, this filter is designed to provide high particle efficiency, low pressure drop, and the ability to be regenerated. These membranes have well-defined micron-sized pores and can be used independently as air filters with discreet particle size cut-off, or coated with nanofiber layers for filtration of ultrafine nanoscale particles. The filter consists of a thin design intended to facilitate filter regeneration by localized air pulsing. The two main features of this invention are the concept of combining a micro-engineered straight-pore membrane with nanofibers. The micro-engineered straight pore membrane can be prepared with extremely high precision. Because the resulting membrane pores are straight and not tortuous like those found in conventional filters, the pressure drop across the filter is significantly reduced. The nanofiber layer is applied as a very thin coating to enhance filtration efficiency for fine nanoscale particles. Additionally, the thin nanofiber coating is designed to promote capture of

  2. Study of slow sand filtration with backwash and the influence of the filter media on the filter recovery and cleaning. (United States)

    de Souza, Fernando Hymnô; Pizzolatti, Bruno Segalla; Schöntag, Juliana Marques; Sens, Maurício Luiz


    Slow sand filters are considered as a great alternative for supplying drinking water in rural and/or isolated areas where raw water that is treatable with this technique is available. Some studies used backwashing as an alternative for cleaning the slow sand filter with the goal of applying the technology in small communities, since filters that supply water to a small number of people do not require much space. In this study the influence of the effective diameter on water quality in the filters and cleaning system was evaluated. A pilot system with six filters was built: three filters were conventionally cleaned by scraping and the other three were cleaned by backwashing, each with a different effective diameter of filter medium. Most filters had an average turbidity of less than 1.0 NTU, the turbidity required at the output of the filters by the Brazilian Ministry of Health Ordinance. In the study, the filters cleaned by scraping with smaller-diameter filter beds effectively filtered water better but had worse effective production. The opposite occurs in the case of backwashed filters.

  3. Fundamentals of Stochastic Filtering

    CERN Document Server

    Crisan, Dan


    The objective of stochastic filtering is to determine the best estimate for the state of a stochastic dynamical system from partial observations. The solution of this problem in the linear case is the well known Kalman-Bucy filter which has found widespread practical application. The purpose of this book is to provide a rigorous mathematical treatment of the non-linear stochastic filtering problem using modern methods. Particular emphasis is placed on the theoretical analysis of numerical methods for the solution of the filtering problem via particle methods. The book should provide sufficient

  4. Stripe delay filters


    Zakharov, Alexander V.; Ilchenko, Mykhailo Ye.; Trubarov, Igor V.; Pinchuk, Ludmila S.


    There are considered constructions of microsized stripe delay filters, which are realized on a basis of ceramic materials with high dielectric permittivity. Delay time of non-minimal phase filters is 7–12 ns at frequencies of 1900 MHz with relative bandwidth of 3.6–3.85%. Filters dimensions are comparable with ones used in portable communication devices. Dimensions of researched three-resonator filter at frequency of 1900 MHz are 8.4×5×2 mm with material dielectric permittivity εr = 92, and 5...

  5. Technology

    Directory of Open Access Journals (Sweden)

    Xu Jing


    Full Text Available The traditional answer card reading method using OMR (Optical Mark Reader, most commonly, OMR special card special use, less versatile, high cost, aiming at the existing problems proposed a method based on pattern recognition of the answer card identification method. Using the method based on Line Segment Detector to detect the tilt of the image, the existence of tilt image rotation correction, and eventually achieve positioning and detection of answers to the answer sheet .Pattern recognition technology for automatic reading, high accuracy, detect faster

  6. Beating heart axillocoronary bypass for management of the untouchable ascending aorta in coronary artery bypass grafting. (United States)

    Bonatti, J; Hangler, H; Oturanlar, D; Posch, L; Müller, L C; Voelckel, W; Schwarz, B; Bodner, G


    Cannulation and clamping of a severely atherosclerotic ascending aorta during coronary artery bypass grafting (CABG) can lead to cerebral embolization of atheromatous debris and should therefore be avoided whenever possible. A variety of surgical techniques including performance of extraanatomical coronary bypass conduits has been described to solve this problem. We report on a preliminary series of four patients in whom the axillary artery was used as an inflow vessel for venous coronary artery bypass grafts which were performed on the beating heart in order to achieve an aortic no touch concept. The axillary artery was exposed between the pectoralis major muscle and the deltoid muscle via an infraclavicular incision. A saphenous vein graft of at least 40 cm in length was sutured to the axillary artery and then brought into the pericardial cavity following an intercostal and transpleural route. The graft was anastomosed to the target vessel using local coronary occlusion. The procedure was carried out via sternotomy in three patients who also received additional internal mammary artery in situ grafts for adequate coronary revascularization. In one high risk patient an isolated axillocoronary bypass was performed in a minimally invasive fashion via anterolateral minithoracotomy. The procedure was completed without major technical difficulties in all four patients. The mean graft length required was 33.2 +/- 1.6 cm, postoperative ultrasonic duplex scans of the axillocoronary grafts revealed a mean flow of 62.5 +/- 23.6 ml/min. No stroke or brachial plexus injury occurred. Three patients are in angina class I (Canadian Cardiovascular Society Classification), one patient is in class II postoperatively. After a mean follow-up of 11.5 +/- 6.6 months postoperatively all grafts remain patent. Axillocoronary bypass grafting can be easily performed for management of the untouchable ascending aorta. Straightforward surgical technique and the accessibility to noninvasive

  7. Arteriovenous fistulas aggravate the hemodynamic effect of vein bypass stenoses

    DEFF Research Database (Denmark)

    Nielsen, Tina G; Djurhuus, Christian Born; Morre-Pedersen, Erik


    PURPOSE: The purpose of this study was to assess the impact of arteriovenous fistulas combined with varying degrees of stenosis on distal bypass hemodynamics and Doppler spectral parameters. METHODS: In an in vitro flow model bypass stenoses causing 30%, 55%, and 70% diameter reduction were induced...... hemodynamic conditions of a more severe stenosis. Assessment of the hemodynamic impact of fistulas must be undertaken in the evaluation of in situ vein bypass stenoses....

  8. Extra-intracranial standard bypass in the elderly

    DEFF Research Database (Denmark)

    Sandow, Nora; von Weitzel-Mudersbach, Paul; Rosenbaum, Sverre


    Patients with chronic atherosclerotic vessel occlusion and cerebrovascular hemodynamic insufficiency may benefit from extra-intracranial (EC-IC) bypass surgery. Due to demographic changes, an increasing number of elderly patients presents with cerebrovascular hemodynamic insufficiency. So far......, little data for EC-IC bypass surgery in elderly patients suffering occlusive cerebrovascular disease are available. We therefore designed a retrospective study to address the question whether EC-IC bypass is a safe and efficient treatment in a patient cohort ≥70 years....

  9. Reconfigurable Ring Filter with Controllable Frequency Response

    Directory of Open Access Journals (Sweden)

    Norfishah Ab Wahab


    Full Text Available Reconfigurable ring filter based on single-side-access ring topology is presented. Using capacitive tuning elements, the electrical length of the ring can be manipulated to shift the nominal center frequency to a desired position. A synthesis is developed to determine the values of the capacitive elements. To show the advantage of the synthesis, it is applied to the reconfigurable filter design using RF lumped capacitors. The concept is further explored by introducing varactor-diodes to continuously tune the center frequency of the ring filter. For demonstration, two prototypes of reconfigurable ring filters are realized using microstrip technology, simulated, and measured to validate the proposed concept. The reconfigured filter using lumped elements is successfully reconfigured from 2 GHz to 984.4 MHz and miniaturized by 71% compared to the filter directly designed at the same reconfigured frequency, while, for the filter using varactor-diodes, the frequency is chosen from 1.10 GHz to 1.38 GHz spreading over 280 MHz frequency range. Both designs are found to be compact with acceptable insertion loss and high selectivity.

  10. Obstetrical and neonatal outcomes in women following gastric bypass

    DEFF Research Database (Denmark)

    Berlac, Janne Foss; Skovlund, Charlotte Wessel; Lidegaard, Ojvind


    OBJECTIVE: To assess obstetrical and neonatal outcomes in women following gastric bypass, compared with adipose women without surgery and with a normal weight control population. DESIGN: Historical controlled cohort study. SETTING: Denmark. POPULATION: All women undergoing gastric bypass during...... the period 1996-2011, and subsequently giving birth. METHODS AND MAIN OUTCOME MEASURES: Obstetrical and neonatal outcomes in women without gastric bypass matched on age, parity, plurality, year, and body mass index, and normal weight women. RESULTS: In 415 women giving birth after gastric bypass we found...

  11. Computer-Generated Holographic Matched Filters (United States)

    Butler, Steven Frank

    This dissertation presents techniques for the use of computer-generated holograms (CGH) for matched filtering. An overview of the supporting technology is provided. Included are techniques for modifying existing CGH algorithms to serve as matched filters in an optical correlator. It shows that matched filters produced in this fashion can be modified to improve the signal-to-noise and efficiency over that possible with conventional holography. The effect and performance of these modifications are demonstrated. In addition, a correction of film non-linearity in continuous -tone filter production is developed. Computer simulations provide quantitative and qualitative demonstration of theoretical principles, with specific examples validated in optical hardware. Conventional and synthetic holograms, both bleached and unbleached, are compared.

  12. System Verilog modelling of FIR filters (United States)

    Pawlus, Łukasz; Wegrzyn, Marek


    In the paper modelling of FIR filters by means of Verilog and SystemVerilog is presented. Hardware/software co-design approach for such systems is applied in the presented design. As a final technology for a FIR filters system implementation, a FPSLIC device is considered. Filters system demonstrates example methods of communication between FPGA and AVR microcontroller in a FPSLIC structure, i.e. the communication through SRAM memory, addressing lines, data bus, interrupts. It also demonstrates how to serve peripheral elements in FPSLIC device by means of DPI interface. FIR filters model contains also interface which implements a FPSLIC cache logic and gives opportunity to a dynamical reconfiguration of FPGA in a FPSLIC structure.

  13. Randomized Filtering Algorithms

    DEFF Research Database (Denmark)

    Katriel, Irit; Van Hentenryck, Pascal


    of AllDifferent and is generalization, the Global Cardinality Constraint. The first delayed filtering scheme is a Monte Carlo algorithm: its running time is superior, in the worst case, to that of enforcing are consistency after every domain event, while its filtering effectiveness is analyzed...

  14. Multilevel ensemble Kalman filter

    KAUST Repository

    Chernov, Alexey


    This work embeds a multilevel Monte Carlo (MLMC) sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF). In terms of computational cost vs. approximation error the asymptotic performance of the multilevel ensemble Kalman filter (MLEnKF) is superior to the EnKF s.

  15. Updating the OMERACT filter

    DEFF Research Database (Denmark)

    Wells, George; Beaton, Dorcas E; Tugwell, Peter


    The "Discrimination" part of the OMERACT Filter asks whether a measure discriminates between situations that are of interest. "Feasibility" in the OMERACT Filter encompasses the practical considerations of using an instrument, including its ease of use, time to complete, monetary costs, and inter...

  16. Fast Anisotropic Gauss Filtering

    NARCIS (Netherlands)

    Geusebroek, J.M.; Smeulders, A.W.M.; van de Weijer, J.; Heyden, A.; Sparr, G.; Nielsen, M.; Johansen, P.


    We derive the decomposition of the anisotropic Gaussian in a one dimensional Gauss filter in the x-direction followed by a one dimensional filter in a non-orthogonal direction phi. So also the anisotropic Gaussian can be decomposed by dimension. This appears to be extremely efficient from a

  17. Vena cava filter; Vena-cava-Filter

    Energy Technology Data Exchange (ETDEWEB)

    Helmberger, T. [Klinikum Bogenhausen, Institut fuer Diagnostische und Interventionelle Radiologie und Nuklearmedizin, Muenchen (Germany)


    Fulminant pulmonary embolism is one of the major causes of death in the Western World. In most cases, deep leg and pelvic venous thrombosis are the cause. If an anticoagulant/thrombotic therapy is no longer possible or ineffective, a vena cava filter implant may be indicated if an embolism is threatening. Implantation of the filter is a simple and safe intervention. Nevertheless, it is necessary to take into consideration that the data base for determining the indications for this treatment are very limited. Currently, a reduction in the risk of thromboembolism with the use of filters of about 30%, of recurrences of almost 5% and fatal pulmonary embolism of 1% has been reported, with a risk of up to 20% of filter induced vena cava thrombosis. (orig.) [German] Die fulminante Lungenembolie zaehlt zu den Haupttodesursachen in der westlichen Welt. In der Mehrzahl der Faelle sind tiefe Bein- und Beckenvenenthrombosen ursaechlich verantwortlich. Ist eine antikoagulative/-thrombotische Therapie nicht (mehr) moeglich oder unwirksam, kann bei drohender Emboliegefahr die Vena-cava-Filterimplantation indiziert sein. Die Filterimplantation ist eine einfache und sehr sichere Intervention. Dennoch muss bei der Indikationsstellung beruecksichtigt werden, dass die Datenlage zur Wirksamkeit sehr limitiert ist. So wird aktuell ueber eine Reduktion des Thrombembolierisikos um 30% bei Embolierezidiven von knapp 5% und fatalen Lungenembolien von 1% unter Filterprophylaxe berichtet, bei einem Risiko von bis zu 20% fuer die filterinduzierte Vena-cava-Thrombose. (orig.)

  18. Using an Artificial Neural Bypass to Restore Cortical Control of Rhythmic Movements in a Human with Quadriplegia (United States)

    Sharma, Gaurav; Friedenberg, David A.; Annetta, Nicholas; Glenn, Bradley; Bockbrader, Marcie; Majstorovic, Connor; Domas, Stephanie; Mysiw, W. Jerry; Rezai, Ali; Bouton, Chad


    Neuroprosthetic technology has been used to restore cortical control of discrete (non-rhythmic) hand movements in a paralyzed person. However, cortical control of rhythmic movements which originate in the brain but are coordinated by Central Pattern Generator (CPG) neural networks in the spinal cord has not been demonstrated previously. Here we show a demonstration of an artificial neural bypass technology that decodes cortical activity and emulates spinal cord CPG function allowing volitional rhythmic hand movement. The technology uses a combination of signals recorded from the brain, machine-learning algorithms to decode the signals, a numerical model of CPG network, and a neuromuscular electrical stimulation system to evoke rhythmic movements. Using the neural bypass, a quadriplegic participant was able to initiate, sustain, and switch between rhythmic and discrete finger movements, using his thoughts alone. These results have implications in advancing neuroprosthetic technology to restore complex movements in people living with paralysis.

  19. Analog active filters (United States)

    Ghausi, M. S.


    The evolution of active filters during the time from 1920 to 1980 is considered, taking into account the hardware used to implement a filtering network for voice frequency over 60 years. From 1920 to 1960 the majority of voice-frequency filters was realized as discrete RLC networks. After the development of transistors, it was realized that size and cost reductions could be achieved by replacing the inductors with active networks. In the early 1970's, batch-processed thin-film hybrid integrated circuits began to be employed. The synthesis of transfer functions which are predominantly input/output types is considered. Attention is given to direct realizations, synthesis using component simulation, cascade synthesis, multiple-loop feedback design, active-R and active-C filters, aspects of sensitivity, and switched-capacitor filters.

  20. Learning Separable Filters. (United States)

    Sironi, Amos; Tekin, Bugra; Rigamonti, Roberto; Lepetit, Vincent; Fua, Pascal


    Learning filters to produce sparse image representations in terms of over-complete dictionaries has emerged as a powerful way to create image features for many different purposes. Unfortunately, these filters are usually both numerous and non-separable, making their use computationally expensive. In this paper, we show that such filters can be computed as linear combinations of a smaller number of separable ones, thus greatly reducing the computational complexity at no cost in terms of performance. This makes filter learning approaches practical even for large images or 3D volumes, and we show that we significantly outperform state-of-the-art methods on the curvilinear structure extraction task, in terms of both accuracy and speed. Moreover, our approach is general and can be used on generic convolutional filter banks to reduce the complexity of the feature extraction step.

  1. Ceramic High Efficiency Particulate Air (HEPA) Filter Final Report CRADA No. TC02160.0

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bergman, W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    The technical objective of this project was to develop a ceramic HEPA filter technology, by initially producing and testing coupon ceramics, small scale prototypes, and full scale prototype HEPA filters, and to address relevant manufacturing and commercialization technical issues.

  2. Indications and Outcomes of Prophylactic and Therapeutic Extracranial-to-intracranial Arterial Bypass for Cerebral Revascularization

    Directory of Open Access Journals (Sweden)

    Emre Gazyakan, MD, MSc


    Conclusions: The collaboration of neurosurgeons and plastic surgeons in performing EC-IC bypass can result in excellent outcomes with a high bypass patency rate and few complications, particularly for prophylactic EC-IC bypass.

  3. Reoperative coronary bypass grafting without cardiopulmonary bypass through a small thoracotomy

    NARCIS (Netherlands)

    Boonstra, PW; Grandjean, JG; Mariani, MA

    Background. The danger of coronary reoperations is mainly hidden in the reopening of the sternum and in the manipulation of the heart and the old grafts. Therefore, the minimally invasive direct coronary artery bypass procedure seems an ideal technique for coronary reoperations if only the left

  4. Bypassing the bandwidth theorem with PT symmetry

    CERN Document Server

    Ramezani, Hamidreza; Ellis, F M; Guenther, Uwe; Kottos, Tsampikos


    The beat time {\\tau}_{fpt} associated with the energy transfer between two coupled oscillators is dictated by the bandwidth theorem which sets a lower bound {\\tau}_{fpt}\\sim 1/{\\delta}{\\omega}. We show, both experimentally and theoretically, that two coupled active LRC electrical oscillators with parity-time (PT) symmetry, bypass the lower bound imposed by the bandwidth theorem, reducing the beat time to zero while retaining a real valued spectrum and fixed eigenfrequency difference {\\delta}{\\omega}. Our results foster new design strategies which lead to (stable) pseudo-unitary wave evolution, and may allow for ultrafast computation, telecommunication, and signal processing.

  5. TRAS principles blight arterial bypass and plasty.

    Directory of Open Access Journals (Sweden)

    Kothari M


    Full Text Available A new concept--Tissue Requisitions (Principle I/Relinquishes (Principle II Arterial Supply--of TRAS principles is introduced to help appreciate the failures/successes of modern medicine′s attempts at restoring arterial flow in luminally compromised coronary/carotid fields, an invasive branch rightly called vascular ReRheology, which comprises diagnosing/treating arterial blocks. The technical wizardry of arterial reconstruction (bypass or lumen--restoration (plasty has to reckon with the TRAS principles all the time.

  6. Work on the Geneva motorway bypass

    CERN Multimedia

    État de Genève, DCTI, Direction du génie civil


    Work on the airport section of the Geneva motorway bypass is continuing and will require the temporary closure of two sliproads allowing traffic to make a U-turn near the airport and the Palexpo exhibition centre. The sliproads on the French and Lausanne sides will be closed until autumn 2006. U-turns will still be possible via clearly marked deviations. For further information: We would like to thank you in advance for your understanding. Civil Engineering Department, DCTI, State of Geneva

  7. Reconfigurable UWB Bandpass Filter with Flexible Notch Characteristics (United States)

    Dhwaj, Kirti

    The thesis reports a compact tunable ultra-wideband (UWB) notch filter using hybrid microstrip and coplanar waveguide (CPW) structure. The tunable notch is implemented to filter out the wireless local area network (WLAN) channels from 5GHz to 6GHz. The proposed structure utilizes the resonance of open ended stubs to achieve transmission zeroes in the filter passband. Varactors and by-pass capacitors are then introduced for dynamic tunability of notch. Further, the electromagnetic decoupling of the two resonators leads to tunable bandwidth of notch. DC bias circuitry is implemented to control the varactor capacitances. Rejection levels up to 25 dB are attained using this technique while maintaining insertion loss levels below 2.5 dB in the passband. The reconfigurability of bandwidth is shown by maintaining a constant bandwidth of 150 MHz across the WLAN band for the notch. The filter achieves an excellent wide bandwidth (from 2.5 GHz to 8.5 GHz) using multimode-resonator (MMR) based topology which makes the filter one wavelength long at the central frequency.

  8. Ceramic fiber reinforced filter (United States)

    Stinton, David P.; McLaughlin, Jerry C.; Lowden, Richard A.


    A filter for removing particulate matter from high temperature flowing fluids, and in particular gases, that is reinforced with ceramic fibers. The filter has a ceramic base fiber material in the form of a fabric, felt, paper of the like, with the refractory fibers thereof coated with a thin layer of a protective and bonding refractory applied by chemical vapor deposition techniques. This coating causes each fiber to be physically joined to adjoining fibers so as to prevent movement of the fibers during use and to increase the strength and toughness of the composite filter. Further, the coating can be selected to minimize any reactions between the constituents of the fluids and the fibers. A description is given of the formation of a composite filter using a felt preform of commercial silicon carbide fibers together with the coating of these fibers with pure silicon carbide. Filter efficiency approaching 100% has been demonstrated with these filters. The fiber base material is alternately made from aluminosilicate fibers, zirconia fibers and alumina fibers. Coating with Al.sub.2 O.sub.3 is also described. Advanced configurations for the composite filter are suggested.

  9. Governmental filtering of websites: The Dutch case

    NARCIS (Netherlands)

    Stol, W.PH.; Kaspersen, H.W.K.; Kerstens, J.; Leukfeldt, E.R.; Lodder, A.R.


    Following the example of Norway and other European Countries, such as Sweden and Denmark, in April 2007 the Dutch government started filtering and blocking web pages with child pornographic content. In this paper we present a research into the technological, legal and practical possibilities of this

  10. Far infrared interference filters. (United States)

    Varma, S P; Möller, K D


    Capacitive meshes for far ir, low pass filters are prepared from Cu layers on 2.5 micro plastic film. The properties of these meshes of different mesh constants g with their different combinations in two-mesh, fourmesh, and eight-mesh filters are studied in the spectral region 160 cm(-1) to 10 cm(-1) by the use of a grating spectrometer. The applications of these meshes as low pass filters in the far ir spectral region in a grating spectrometer are described.

  11. Circuits and filters handbook

    CERN Document Server

    Chen, Wai-Kai


    A bestseller in its first edition, The Circuits and Filters Handbook has been thoroughly updated to provide the most current, most comprehensive information available in both the classical and emerging fields of circuits and filters, both analog and digital. This edition contains 29 new chapters, with significant additions in the areas of computer-aided design, circuit simulation, VLSI circuits, design automation, and active and digital filters. It will undoubtedly take its place as the engineer's first choice in looking for solutions to problems encountered in the design, analysis, and behavi

  12. EMI filter design

    CERN Document Server

    Ozenbaugh, Richard Lee


    With today's electrical and electronics systems requiring increased levels of performance and reliability, the design of robust EMI filters plays a critical role in EMC compliance. Using a mix of practical methods and theoretical analysis, EMI Filter Design, Third Edition presents both a hands-on and academic approach to the design of EMI filters and the selection of components values. The design approaches covered include matrix methods using table data and the use of Fourier analysis, Laplace transforms, and transfer function realization of LC structures. This edition has been fully revised

  13. Diagnostic tools for post-gastric bypass hypoglycaemia

    NARCIS (Netherlands)

    Emous, M.; Ubels, F. L.; van Beek, A. P.


    In spite of its evident success, several late complications can occur after gastric bypass surgery. One of these is post-gastric bypass hypoglycaemia. No evidence-based guidelines exist in the literature on how to confirm the presence of this syndrome. This study aims to describe and compare the

  14. Sen perforation af tyndtarm efter laparoskopisk gastrisk bypass

    DEFF Research Database (Denmark)

    Spanager, Lene; Sigild, Ulf Henrik; Neuenschwander, Anders Ulrich


    We present two cases in which the patients were admitted to a local hospital with acute abdominal pain four or five months after having undergone laparoscopic gastric bypass. In both cases, operation revealed a perforation of the small bowel close to the distal anastomosis. In the first case...... bypass but as our two cases illustrate they are important to keep in mind....

  15. Lower leg electrical impedance after distal bypass surgery

    DEFF Research Database (Denmark)

    Belanger, G K; Bolbjerg, M L; Heegaard, N H


    Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816...... to be a useful method for the evaluation of lower leg oedema after distal bypass surgery....

  16. Inpatient healthcare provider bypassing by women and their ...

    African Journals Online (AJOL)

    Introduction: bypassing refers to a person's decision to seek care at a healthcare facility that is not the nearest one of its type to the person's home. Methods: this study examined inpatient care facility bypassing in urban Bo, Sierra Leone using data from 1,980 women with children 15 years of age and younger who were ...

  17. Reverse bias protected solar array with integrated bypass battery (United States)

    Landis, Geoffrey A (Inventor)


    A method for protecting the photovoltaic cells in a photovoltaic (PV) array from reverse bias damage by utilizing a rechargeable battery for bypassing current from a shaded photovoltaic cell or group of cells, avoiding the need for a bypass diode. Further, the method mitigates the voltage degradation of a PV array caused by shaded cells.

  18. Basics of cardiopulmonary bypass: normal and abnormal postoperative CT appearances. (United States)

    El-Sherief, Ahmed H; Wu, Carol C; Schoenhagen, Paul; Little, Brent P; Cheng, Allen; Abbara, Suhny; Roselli, Eric E


    Cardiothoracic surgical procedures with and without cardiopulmonary bypass are becoming more commonly performed as surgical techniques improve and the population ages. Changes related to cardiopulmonary bypass are often depicted at routine postoperative computed tomographic (CT) studies performed for various reasons. The purpose of this article is to present knowledge critical to the accurate postoperative evaluation of the patient who has undergone cardiopulmonary bypass. This article will review the surgical technique for cardiopulmonary bypass, as well as the associated normal and abnormal postoperative imaging findings. Common cannulation sites used for cardiopulmonary bypass include the ascending aorta, axillary artery, right atrium, superior vena cava, and inferior vena cava. Normal postoperative findings related to cardiopulmonary bypass include (a) felt pledgets, which are used to reinforce cannulation sites; (b) oversewn side grafts; and (c) oversewn graft side branches. These normal postoperative findings can be mistaken for abnormalities. Abnormal postoperative findings related to cardiopulmonary bypass include pseudoaneurysm formation at cannulation sites, aortic dissection, and seroma formation. An awareness of normal and abnormal postoperative CT findings related to cardiopulmonary bypass is critical for all radiologists who interpret chest CT studies, to help prevent unnecessary further evaluation and to help direct prompt treatment when warranted.

  19. Computed tomography perfusion evaluation after extracranial-intracranial bypass surgery

    NARCIS (Netherlands)

    Vos, Pieter C.; Riordan, Alan J.; Smit, Ewoud J.; de Jong, Hugo W. A. M.; van der Zwan, Albert; Velthuis, BK; Viergever, Max A.; Dankbaar, Jan Willem

    Objective: Perfusion imaging is increasingly used for postoperative evaluation of extracranial to intracranial (EC-IC) bypass surgery. Altered hemodynamics and delayed arrival of the contrast agent in the area fed by the bypass can influence perfusion measurement. We compared perfusion asymmetry

  20. What to Expect during Coronary Artery Bypass Grafting (United States)

    ... an illustration, go to the Health Topics Heart Surgery article. The surgeon will take an artery or vein from your body—for example, from your chest or leg—to use as the bypass graft. For surgeries with several bypasses, both artery and vein grafts ...

  1. Predicting the need for blood during cardiopulmonary bypass

    African Journals Online (AJOL)


    infections.1 Furthermore, autologous blood transfusions relieve pres- sure on scarce banked-blood ... delivery that occurs on initiation of cardiopulmonary bypass (CPB). In spite of patient cooling during CPB that ... considered prudent to have blood ready in the operating room at the time of going onto bypass in order to ...

  2. A low-loss, continuously tunable microwave notch filter

    DEFF Research Database (Denmark)

    Acar, Öncel; Johansen, Tom Keinicke; Zhurbenko, Vitaliy


    The development in high-end microwave transceiver systems toward the software defined radio has brought about the need for tunable frontend filters. Although the problem is being tackled by the microwave community, there still appears to be an unmet demand for practical tunable filter technologies...

  3. Power and Aging Characterization of Digital FIR Filters Architectures

    DEFF Research Database (Denmark)

    Calimera, Andrea; Liu, Wei; Macii, Enrico


    -variation, temperature and aging induced variations pose new challenges in the fabrication of the next generation of ICs. This work presents a detailed power and aging characterization of digital FIR filters in an industrial 45nm CMOS technology, and a design space exploration of different filter architectures...

  4. Effectiveness of adverse effects search filters: drugs versus medical devices

    Directory of Open Access Journals (Sweden)

    Kelly Farrah, MLIS, AHIP


    Full Text Available Objective: The study tested the performance of adverse effects search filters when searching for safety information on medical devices, procedures, and diagnostic tests in MEDLINE and Embase. Methods: The sensitivity of 3 filters was determined using a sample of 631 references from 131 rapid reviews related to the safety of health technologies. The references were divided into 2 sets by type of intervention: drugs and nondrug health technologies. Keyword and indexing analysis were performed on references from the nondrug testing set that 1 or more of the filters did not retrieve. Results: For all 3 filters, sensitivity was lower for nondrug health technologies (ranging from 53%– 87% than for drugs (88%–93% in both databases. When tested on the nondrug health technologies set, sensitivity was lower in Embase (ranging from 53%–81% than in MEDLINE (67%–87% for all filters. Of the nondrug records that 1 or more of the filters missed, 39% of the missed MEDLINE records and 18% of the missed Embase records did not contain any indexing terms related to adverse events. Analyzing the titles and abstracts of nondrug records that were missed by any 1 filter, the most commonly used keywords related to adverse effects were: risk, complications, mortality, contamination, hemorrhage, and failure. Conclusions: In this study, adverse effects filters were less effective at finding information about the safety of medical devices, procedures, and tests compared to information about the safety of drugs.

  5. Outcomes of coronary artery bypass graft surgery

    Directory of Open Access Journals (Sweden)

    Anna Louise Hawkes


    Full Text Available Anna Louise Hawkes1,3, Madeleine Nowak1, Benjamin Bidstrup2, Richard Speare11School of Public Health, Tropical, Medicine and Rehabilitation Sciences, James Cook University, Townsville, Queensland, Australia (3Currently Queensland Cancer Fund; 2John Flynn Hospital, Gold Coast, Queensland, AustraliaAbstract: This review article summarizes the major studies that have investigated the outcomes of coronary artery bypass graft surgery (CABG. The article includes a review of the literature in the areas of: history of CABG; indications for CABG; and measurement of quality of life following CABG, including prolongation of life, physical functioning (ie, relief from angina and dyspnea, physical activity, as well as complications of surgery and re-hospitalization, psychological functioning, and social functioning. Overall, the literature demonstrates that the outcomes of CABG have historically been measured in terms of mortality and morbidity; however, it has now been well recognized that adjustment to CABG is a multidimensional phenomenon that is not fully explained by medical factors. Therefore, in addition to studying mortality and morbidity outcomes following CABG, many recent studies have identified that it is important to investigate various physical, psychological, and social variables that have a significant impact on post-operative adjustment to CABG. Keywords: coronary artery bypass graft surgery, outcomes, quality of life, recovery

  6. Cardiopulmonary bypass in the pediatric population. (United States)

    Whiting, David; Yuki, Koichi; DiNardo, James A


    Cardiopulmonary bypass (CPB) facilitates the repair of cardiac lesions in adults and children. Surgical mortality has decreased with improvements in technique allowing for the successful repair of complex heart defects in neonates of increasingly low body weight and gestational age. The physiological effects of CPB are more significant in children. The presence of intracardiac shunts and other anatomic variants further complicates CPB in patients with congenital heart disease. Special techniques and monitors are often necessary. Protocols are often established within individual institutions to standardize the approach to CPB. The anesthesiologist caring for the patient must understand the physiology of CPB to facilitate the initiation and separation from bypass, and to be able to treat complications. Evidence supporting a particular technique of CPB in pediatric population is still largely from uncontrolled or nonrandomized trials, observational studies, extrapolation from adult studies, and expert opinion. The heterogeneity of congenital heart disease makes randomized controlled trials or meta-analyses challenging, and thus they are limited in the literature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Strategies to prevent intraoperative lung injury during cardiopulmonary bypass (United States)


    During open heart surgery the influence of a series of factors such as cardiopulmonary bypass (CPB), hypothermia, operation and anaesthesia, as well as medication and transfusion can cause a diffuse trauma in the lungs. This injury leads mostly to a postoperative interstitial pulmonary oedema and abnormal gas exchange. Substantial improvements in all of the above mentioned factors may lead to a better lung function postoperatively. By avoiding CPB, reducing its time, or by minimizing the extracorporeal surface area with the use of miniaturized circuits of CPB, beneficial effects on lung function are reported. In addition, replacement of circuit surface with biocompatible surfaces like heparin-coated, and material-independent sources of blood activation, a better postoperative lung function is observed. Meticulous myocardial protection by using hypothermia and cardioplegia methods during ischemia and reperfusion remain one of the cornerstones of postoperative lung function. The partial restoration of pulmonary artery perfusion during CPB possibly contributes to prevent pulmonary ischemia and lung dysfunction. Using medication such as corticosteroids and aprotinin, which protect the lungs during CPB, and leukocyte depletion filters for operations expected to exceed 90 minutes in CPB-time appear to be protective against the toxic impact of CPB in the lungs. The newer methods of ultrafiltration used to scavenge pro-inflammatory factors seem to be protective for the lung function. In a similar way, reducing the use of cardiotomy suction device, as well as the contact-time between free blood and pericardium, it is expected that the postoperative lung function will be improved. PMID:20064238

  8. Developing metal coated mesh filters for mid-infrared astronomy (United States)

    Sako, Shigeyuki; Miyata, Takashi; Kamizuka, Takafumi; Nakamura, Tomohiko; Asano, Kentaro; Uchiyama, Mizuho; Onaka, Takashi; Sakon, Itsuki; Wada, Takehiko


    A metal mesh filter is appropriate to a band-pass filter for astronomy in the long mid-infrared between 25 and 40 μm, where most of optical materials are opaque. The mesh filter does not require transparent dielectric materials unlike interference filters because the transmission characteristics bare determined by surface plasmon-polariton (SPP) resonances excited on a metal surface with a periodic structure. In this study, we have developed the mesh filters optimized to atmospheric windows at 31.8 and 37.5 μm accessible from the Chajnantor site of 5,640 m altitude. First, mesh filters made of a gold film of 2 μm thickness have been fabricated. Four identical film-type filters are stacked incoherently to suppress leakages at stop-bands. The transmissions of the stacked filters have been measured to be 0.8 at the peaks and below 1 x 10-3 at the stop-bands at 4 K. The ground-based mid-infrared camera MAX38 has been equipped with the stacked filters and successfully obtained diffraction-limited stellar images at the Chajnantor site. The film-type mesh filter does not have sufficient mechanical strength for a larger aperture and for use in space. We have developed mesh filters with higher strength by applying the membrane technology for x-ray optics. The membrane-type mesh filter is made of SiC and coated with a thin gold layer. The optical performance of the mesh filter is independent of internal materials in principle because the SPP resonances are excited only on the metal surface. The fabricated membrane-type mesh filter has been confirmed to provide comparable optical performance to the film-type mesh filter.

  9. Cardiopulmonary bypass: development of John Gibbon's heart-lung machine. (United States)

    Passaroni, Andréia Cristina; Silva, Marcos Augusto de Moraes; Yoshida, Winston Bonetti


    To provide a brief review of the development of cardiopulmonary bypass. A review of the literature on the development of extracorporeal circulation techniques, their essential role in cardiovascular surgery, and the complications associated with their use, including hemolysis and inflammation. The advancement of extracorporeal circulation techniques has played an essential role in minimizing the complications of cardiopulmonary bypass, which can range from various degrees of tissue injury to multiple organ dysfunction syndrome. Investigators have long researched the ways in which cardiopulmonary bypass may insult the human body. Potential solutions arose and laid the groundwork for development of safer postoperative care strategies. Steady progress has been made in cardiopulmonary bypass in the decades since it was first conceived of by Gibbon. Despite the constant evolution of cardiopulmonary bypass techniques and attempts to minimize their complications, it is still essential that clinicians respect the particularities of each patient's physiological function.

  10. Paul Rodgersi filter Kohilas

    Index Scriptorium Estoniae


    28. I Kohila keskkoolis kohaspetsiifiline skulptuur ja performance "Filter". Kooli 130. aastapäeva tähistava ettevõtmise eesotsas oli skulptor Paul Rodgers ja kaks viimase klassi noormeest ئ Marko Heinmäe, Hendrik Karm.

  11. Perspectives on Nonlinear Filtering

    KAUST Repository

    Law, Kody


    The solution to the problem of nonlinear filtering may be given either as an estimate of the signal (and ideally some measure of concentration), or as a full posterior distribution. Similarly, one may evaluate the fidelity of the filter either by its ability to track the signal or its proximity to the posterior filtering distribution. Hence, the field enjoys a lively symbiosis between probability and control theory, and there are plenty of applications which benefit from algorithmic advances, from signal processing, to econometrics, to large-scale ocean, atmosphere, and climate modeling. This talk will survey some recent theoretical results involving accurate signal tracking with noise-free (degenerate) dynamics in high-dimensions (infinite, in principle, but say d between 103 and 108 , depending on the size of your application and your computer), and high-fidelity approximations of the filtering distribution in low dimensions (say d between 1 and several 10s).

  12. Updating the OMERACT filter

    DEFF Research Database (Denmark)

    D'Agostino, Maria-Antonietta; Boers, Maarten; Kirwan, John


    OBJECTIVE: The Outcome Measures in Rheumatology (OMERACT) Filter provides a framework for the validation of outcome measures for use in rheumatology clinical research. However, imaging and biochemical measures may face additional validation challenges because of their technical nature. The Imagin...

  13. Compact photonic spin filters (United States)

    Ke, Yougang; Liu, Zhenxing; Liu, Yachao; Zhou, Junxiao; Shu, Weixing; Luo, Hailu; Wen, Shuangchun


    In this letter, we propose and experimentally demonstrate a compact photonic spin filter formed by integrating a Pancharatnam-Berry phase lens (focal length of ±f ) into a conventional plano-concave lens (focal length of -f). By choosing the input port of the filter, photons with a desired spin state, such as the right-handed component or the left-handed one, propagate alone its original propagation direction, while the unwanted spin component is quickly diverged after passing through the filter. One application of the filter, sorting the spin-dependent components of vector vortex beams on higher-order Poincaré sphere, is also demonstrated. Our scheme provides a simple method to manipulate light, and thereby enables potential applications for photonic devices.

  14. Molecular circuits for dynamic noise filtering. (United States)

    Zechner, Christoph; Seelig, Georg; Rullan, Marc; Khammash, Mustafa


    The invention of the Kalman filter is a crowning achievement of filtering theory-one that has revolutionized technology in countless ways. By dealing effectively with noise, the Kalman filter has enabled various applications in positioning, navigation, control, and telecommunications. In the emerging field of synthetic biology, noise and context dependency are among the key challenges facing the successful implementation of reliable, complex, and scalable synthetic circuits. Although substantial further advancement in the field may very well rely on effectively addressing these issues, a principled protocol to deal with noise-as provided by the Kalman filter-remains completely missing. Here we develop an optimal filtering theory that is suitable for noisy biochemical networks. We show how the resulting filters can be implemented at the molecular level and provide various simulations related to estimation, system identification, and noise cancellation problems. We demonstrate our approach in vitro using DNA strand displacement cascades as well as in vivo using flow cytometry measurements of a light-inducible circuit in Escherichia coli.

  15. Assessment of high-temperature filtering elements

    Energy Technology Data Exchange (ETDEWEB)

    Monica Lupion; Francisco J. Gutierrez Ortiz; Benito Navarrete; Vicente J. Cortes [University of Seville, Seville (Spain). E.T.S. Ingenieros


    A complete experimental campaign has been carried out in a hot gas filtration test facility so as to test several filtering elements and configurations, particularly, three different types of bag filters and one ceramic candle. The facility was designed to operate under a wide range of conditions, thus providing an excellent tool for the investigation of hot gas filtration applications for the advanced electrical power generation industry such as IGCC, PFBC or fuel cell technologies. Relevant parameters for the characterization and optimization of the performance of the filters have been studied for a variety of operation conditions such as filtration velocity, particle concentration, pressure and temperature among others. Pressure drop across the filter, cleaning pulse interval, baseline pressure drop, filtration efficiency and durability of the filter have been investigated for each type considered and dependences on parameters have been established. On top of that, optimal operating conditions and cleaning strategies were determined. The tests results show that bag filters are a suitable alternative for the hot gas filtration due to the better performance and the high efficiency observed, which makes them suitable for industrial applications operating under high temperature high pressure conditions considered within the study (200-370{degree}C and 4-7.5 barg respectively). 7 refs., 7 figs., 10 tabs.

  16. The impact of haemodilution and bypass pump flow on cerebral oxygen desaturation during cardiopulmonary bypass--A comparison of two systems of cardiopulmonary bypass. (United States)

    Bennett, M J; Weatherall, M; Webb, G; Dudnikov, S F; Lloyd, C T


    To determine the influence of haemodilution, bypass flow rates and calculated oxygen delivery during cardiopulmonary bypass (CPB) with either a conventional CPB (C-CPB) circuit or a miniaturised (Mini-CPB) circuit on cerebral oxygen desaturation. The effect of minimal haemodilution with a Mini-CPB was investigated. Eighty patients scheduled for elective cardiac surgery. Oxygenated haemoglobin (O2Hb) and tissue oxygenation index (TOI) were measured with near-infrared spectroscopy (NIRS). The average indexed bypass pump flow was significantly lower with Mini-CPB. When combined with haemoglobin concentration, the average oxygen delivery was the same between groups. Patients in the C-CPB group had a greater duration and severity of cerebral desaturation to a level bypass, whereas desaturation with Mini-CPB was associated with low perioperative haemoglobin concentration. © The Author(s) 2014.

  17. Filtered stochastic calculus


    Lenczewski, Romuald


    By introducing a color filtration to the multiplicity space, we extend the quantum Ito calculus on multiple symmetric Fock space to the framework of filtered adapted biprocesses. In this new notion of adaptedness,``classical'' time filtration makes the integrands similar to adapted processes, whereas ``quantum'' color filtration produces their deviations from adaptedness. An important feature of this calculus, which we call filtered stochastic calculus, is that it provides an explicit interpo...

  18. Impact of a silver layer on the membrane of tap water filters on the microbiological quality of filtered water. (United States)

    Vonberg, Ralf-Peter; Sohr, Dorit; Bruderek, Juliane; Gastmeier, Petra


    Bacteria in the hospital's drinking water system represent a risk for the acquisition of a nosocomial infection in the severely immunocompromised host. Terminal tap water filters may be used to prevent nosocomial Legionnaires' disease. We present data from water samples using an improved kind of tap water filters. In a blinded study on an intermediate care unit of the thoracic surgery department, a modified type of the Germlyser water filter (Aqua-Free Membrane Technology) with a newly-introduced silver layer on the filtration membrane was compared to its preceding type without such a layer on 15 water outlets. We determined growth of Legionella, other pathogenic bacteria, and the total heterotrophic plate count in unfiltered water and filtered water samples after filter usage intervals of 1 through 4 weeks. A total of 299 water samples were tested. Twenty-nine of the 60 unfiltered water samples contained Legionella of various serogroups (baseline value). In contrast, all samples filtered by the original water filter and all but one of the water samples filtered by the modified filter type remained Legionella-free. No other pathogenic bacteria were detected in any filtered sample. The total plate count in water samples increased during use of both kinds of filters over time. However, for the first 7 days of use, there were significantly fewer water samples containing >100 CFU per mL when using the new filter device compared with the older filters or taps with no filter. No advantage was seen thereafter. The use of this type of terminal water filter is an appropriate method to protect immunocompromised patients from water-borne pathogens such as Legionella.

  19. Impact of a silver layer on the membrane of tap water filters on the microbiological quality of filtered water

    Directory of Open Access Journals (Sweden)

    Bruderek Juliane


    Full Text Available Abstract Background Bacteria in the hospital's drinking water system represent a risk for the acquisition of a nosocomial infection in the severely immunocompromised host. Terminal tap water filters may be used to prevent nosocomial Legionnaires' disease. We present data from water samples using an improved kind of tap water filters. Methods In a blinded study on an intermediate care unit of the thoracic surgery department, a modified type of the Germlyser water filter (Aqua-Free Membrane Technology with a newly-introduced silver layer on the filtration membrane was compared to its preceding type without such a layer on 15 water outlets. We determined growth of Legionella, other pathogenic bacteria, and the total heterotrophic plate count in unfiltered water and filtered water samples after filter usage intervals of 1 through 4 weeks. Results A total of 299 water samples were tested. Twenty-nine of the 60 unfiltered water samples contained Legionella of various serogroups (baseline value. In contrast, all samples filtered by the original water filter and all but one of the water samples filtered by the modified filter type remained Legionella-free. No other pathogenic bacteria were detected in any filtered sample. The total plate count in water samples increased during use of both kinds of filters over time. However, for the first 7 days of use, there were significantly fewer water samples containing >100 CFU per mL when using the new filter device compared with the older filters or taps with no filter. No advantage was seen thereafter. Conclusion The use of this type of terminal water filter is an appropriate method to protect immunocompromised patients from water-borne pathogens such as Legionella.

  20. Contactor/filter improvements (United States)

    Stelman, David


    A contactor/filter arrangement for removing particulate contaminants from a gaseous stream includes a housing having a substantially vertically oriented granular material retention member with upstream and downstream faces, a substantially vertically oriented microporous gas filter element, wherein the retention member and the filter element are spaced apart to provide a zone for the passage of granular material therethrough. The housing further includes a gas inlet means, a gas outlet means, and means for moving a body of granular material through the zone. A gaseous stream containing particulate contaminants passes through the gas inlet means as well as through the upstream face of the granular material retention member, passing through the retention member, the body of granular material, the microporous gas filter element, exiting out of the gas outlet means. Disposed on the upstream face of the filter element is a cover screen which isolates the filter element from contact with the moving granular bed and collects a portion of the particulates so as to form a dust cake having openings small enough to exclude the granular material, yet large enough to receive the dust particles. In one embodiment, the granular material is comprised of prous alumina impregnated with CuO, with the cover screen cleaned by the action of the moving granular material as well as by backflow pressure pulses.

  1. Inorganic UV filters

    Directory of Open Access Journals (Sweden)

    Eloísa Berbel Manaia


    Full Text Available Nowadays, concern over skin cancer has been growing more and more, especially in tropical countries where the incidence of UVA/B radiation is higher. The correct use of sunscreen is the most efficient way to prevent the development of this disease. The ingredients of sunscreen can be organic and/or inorganic sun filters. Inorganic filters present some advantages over organic filters, such as photostability, non-irritability and broad spectrum protection. Nevertheless, inorganic filters have a whitening effect in sunscreen formulations owing to the high refractive index, decreasing their esthetic appeal. Many techniques have been developed to overcome this problem and among them, the use of nanotechnology stands out. The estimated amount of nanomaterial in use must increase from 2000 tons in 2004 to a projected 58000 tons in 2020. In this context, this article aims to analyze critically both the different features of the production of inorganic filters (synthesis routes proposed in recent years and the permeability, the safety and other characteristics of the new generation of inorganic filters.

  2. Low Power Systolic Array Based Digital Filter for DSP Applications

    Directory of Open Access Journals (Sweden)

    S. Karthick


    Full Text Available Main concepts in DSP include filtering, averaging, modulating, and correlating the signals in digital form to estimate characteristic parameter of a signal into a desirable form. This paper presents a brief concept of low power datapath impact for Digital Signal Processing (DSP based biomedical application. Systolic array based digital filter used in signal processing of electrocardiogram analysis is presented with datapath architectural innovations in low power consumption perspective. Implementation was done with ASIC design methodology using TSMC 65 nm technological library node. The proposed systolic array filter has reduced leakage power up to 8.5% than the existing filter architectures.

  3. Distributed Kalman-Consensus Filtering for Sparse Signal Estimation

    Directory of Open Access Journals (Sweden)

    Yisha Liu


    Full Text Available A Kalman filtering-based distributed algorithm is proposed to deal with the sparse signal estimation problem. The pseudomeasurement-embedded Kalman filter is rebuilt in the information form, and an improved parameter selection approach is discussed. By introducing the pseudomeasurement technology into Kalman-consensus filter, a distributed estimation algorithm is developed to fuse the measurements from different nodes in the network, such that all filters can reach a consensus on the estimate of sparse signals. Some numerical examples are provided to demonstrate the effectiveness of the proposed approach.

  4. Miniature Microwave Bandpass Filter Based on EBG Structures

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Krozer, Viktor; Meincke, Peter


    as compared to stepped-impedance hairpin (SIH) resonators with similar response. The new bandpass filter has a reduced footprint and can be fabricated in standard thick-film manufacturing technology. Measured and simulated results exhibit good agreement. The measured results show improvement in the filter......A new design of a planar microwave filter, based on rejection band properties of an electrically small electromagnetic bandgap (EBG) structure, is proposed. The proposed EBG structure demonstrates effective impedance manipulation, exhibits a simple analysis, and is about three times smaller...... characteristics in comparison to existing SIH filter design....

  5. Modern analog filter analysis and design a practical approach

    CERN Document Server

    Raut, R


    Starting from the fundamentals, the present book describes methods of designing analog electronic filters and illustrates these methods by providing numerical and circuit simulation programs. The subject matters comprise many concepts and techniques that are not available in other text books on the market. To name a few - principle of transposition and its application in directly realizing current mode filters from well known voltage mode filters; an insight into the technological aspect of integrated circuit components used to implement an integrated circuit filter; a careful blending of basi

  6. Can pregnant women be safely placed on cardiopulmonary bypass? (United States)

    Sepehripour, Amir H; Lo, Tammy T; Shipolini, Alex R; McCormack, David J


    A best evidence topic was written according to a structured protocol. The question addressed was whether cardiopulmonary bypass can be used safely with satisfactory maternal and foetal outcomes in pregnant patients undergoing cardiac surgery. A total of 679 papers were found using the reported searches of which 14 represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. Reported measures were maternal and foetal mortality and complications, mode of delivery, cardiopulmonary bypass and aortic cross-clamp times, perfusate flow rate and temperature and maternal NYHA functional class. The most recent of the best evidence studies, a retrospective observational study of 21 pregnant patients reported early and late maternal mortalities of 4.8 and 14.3%, respectively, and a foetal mortality of 14.3%. Median cardiopulmonary bypass and aortic cross-clamp times were 53 and 35 min, respectively, and the median bypass temperature was 37°C. Three larger retrospective reviews of the literature reported maternal mortality rates of 2.9-5.1% and foetal mortality rates of 19-29%. Mean cardiopulmonary bypass times ranged from 50.5 to 77.8 min. Another retrospective observational study reported maternal mortality of 13.3% and foetal mortality of 38.5%. Mean cardiopulmonary bypass and aortic cross-clamp times were 89.1 and 62.8 min, respectively, with a mean bypass temperature of 31.8°C. A retrospective case series reported no maternal mortality and one case of foetal mortality. Median cardiopulmonary bypass and aortic cross-clamp times were 101 and 88 min, respectively. Eight case reports described 10 patients undergoing cardiopulmonary bypass. There were no reports of maternal mortality and one report of foetal mortality. Mean cardiopulmonary bypass and aortic cross-clamp times were 105 and 50 min, respectively. We conclude that while the use of cardiopulmonary bypass

  7. Low serum sodium level during cardiopulmonary bypass predicts increased risk of postoperative stroke after coronary artery bypass graft surgery. (United States)

    Munoz, Elizandro; Briggs, Holly; Tolpin, Daniel A; Lee, Vei-Vei; Crane, Terry; Elayda, Macarthur A; Collard, Charles D; Pan, Wei


    Rapid decreases in serum sodium levels are associated with altered mental status, seizures, and coma. During cardiac surgery, serum sodium levels decrease rapidly when cardiopulmonary bypass is initiated because cardiopulmonary bypass causes hemodilution. However, whether this decrease influences neurologic outcome after cardiac surgery remains unclear. We investigated whether the average serum sodium level during cardiopulmonary bypass is independently predictive of postoperative stroke or 30-day all-cause mortality in patients who undergo primary coronary artery bypass grafting. In a single-institution, retrospective cohort of 2348 consecutive patients who underwent primary, isolated coronary artery bypass grafting, sequential multivariate logistic regression was performed to determine the threshold below which the average serum sodium level during cardiopulmonary bypass independently predicts postoperative stroke or early death. To further test the validity of this threshold and to control for selection bias, stepwise multivariate logistic regression was also performed on propensity score-matched patients (n = 924). An average serum sodium level less than 130 mEq/L during cardiopulmonary bypass was independently predictive of stroke, both in the entire study cohort (1.44% vs 2.92%; odds ratio, 2.09; 95% confidence interval, 1.1-4.1; P = .03) and in the propensity-matched patients (0.9% vs 3.0%; odds ratio, 4.1; 95% confidence interval, 1.3-13.0; P = .02). The average serum sodium level during cardiopulmonary bypass was not independently associated with early death, regardless of what threshold value was used. An average serum sodium level of less than 130 mEq/L during cardiopulmonary bypass is independently associated with an increased risk of postoperative stroke in patients who undergo primary coronary artery bypass grafting. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  8. A New Adaptive H-Infinity Filtering Algorithm for the GPS/INS Integrated Navigation. (United States)

    Jiang, Chen; Zhang, Shu-Bi; Zhang, Qiu-Zhao


    The Kalman filter is an optimal estimator with numerous applications in technology, especially in systems with Gaussian distributed noise. Moreover, the adaptive Kalman filtering algorithms, based on the Kalman filter, can control the influence of dynamic model errors. In contrast to the adaptive Kalman filtering algorithms, the H-infinity filter is able to address the interference of the stochastic model by minimization of the worst-case estimation error. In this paper, a novel adaptive H-infinity filtering algorithm, which integrates the adaptive Kalman filter and the H-infinity filter in order to perform a comprehensive filtering algorithm, is presented. In the proposed algorithm, a robust estimation method is employed to control the influence of outliers. In order to verify the proposed algorithm, experiments with real data of the Global Positioning System (GPS) and Inertial Navigation System (INS) integrated navigation, were conducted. The experimental results have shown that the proposed algorithm has multiple advantages compared to the other filtering algorithms.

  9. Laparoscopic Conversion of One Anastomosis Gastric Bypass to a Standard Roux-en-Y Gastric Bypass. (United States)

    Amor, Imed Ben; Petrucciani, Niccolo; Kassir, Radwan; Al Munifi, Abdullah; Piche, Thierry; Debs, Tarek; Gugenheim, Jean


    One anastomosis gastric bypass (OAGB) demonstrated results similar to traditional Roux-en-Y procedures [1-3], in terms of weight loss and resolution of obesity-related comorbidities. The main controversy regarding OAGB is the concern for an association between biliary alkaline gastritis and esophageal or gastric cancer raised by some studies [4]. We present the case of a 51-year-old woman with a BMI of 41 kg/m2 who underwent a laparoscopic OAGB in 2014. One year later, she consulted for recurrent heartburns. An upper GI endoscopy showed pouchitis and bile reflux in the esophagus. Medical treatment of gastroesophageal reflux disease was ineffective. We decided to convert the OAGB to a Roux-en-Y gastric bypass (RYGB). In this video, we show how to revise an OAGB to treat chronic bile reflux, by converting the procedure to a standard RYGB. The intervention starts by restoring the normal anatomy of the small bowel, with the resection of the gastrojejunal anastomosis, which was located at 250-cm du Treitz's ligament. Then, the gastric pouch is created. A standard Roux-en-Y gastric bypass is performed. The resection of the gastrojejunal anastomosis allows fashioning the Roux-en-Y limb with the classical measures. This technique allows a conversion to a standard RYGB and is effective in treating the biliary reflux.

  10. Effects of a leukocyte depleting arterial line filter on perioperative morbidity in patients undergoing cardiac surgery: a controlled randomized trial. (United States)

    Leal-Noval, Santiago R; Amaya, Rosario; Herruzo, Angel; Hernández, Ana; Ordóñez, Antonio; Marín-Niebla, Ana; Camacho, Pedro


    Activated leukocytes may increase morbidity in cardiac surgery. The objective of this study is to investigate the influence on morbidity of leukocyte-depleting blood filters placed into the arterial line of cardiopulmonary bypass circuits. Simple, blind, prospective, randomized and controlled clinical trial carried out in a cardiac surgery ICU at a university center. We included 159 consecutive low-risk patients (ie, Parsonnet score < 10) undergoing cardiac surgery who were initially stratified in three risk levels according to the Parsonnet score at admission into the hospital (ie, low, < 4; middle, 4 to 7; and high, 8 to 10). Once stratified, all patients were randomized to undergo cardiopulmonary bypass either with a conventional blood filter or with a leukocyte filter (randomization ratio, 2:1). The outcome variable was morbidity. Patients were considered to have a high morbidity if any of the following clinical situations were present (ie, pulmonary dysfunction, cardiac dysfunction, perioperative infections, postoperative hyperthermia, and hyperdynamic states). The leukocyte filter was used in 52 patients and the conventional filter in 107 patients. The morbidity rate was similar in both groups, but patients with leukocyte filter had a lower incidence of perioperative infections, fever, and hyperdynamic states as compared with patients with the conventional filter. Leukocyte filtration in patients undergoing cardiac surgery with extracorporeal perfusion showed no measurable effects on postoperative morbidity. However, although not statistically significant, a decrease was observed in the rates of perioperative infection, fever, and hyperdynamic states.

  11. Transient Diabetes Insipidus Following Cardiopulmonary Bypass. (United States)

    Ekim, Meral; Ekim, Hasan; Yilmaz, Yunus Keser; Bolat, Ali


    Diabetes insipidus (DI) results from inadequate output of Antidiuretic Hormone (ADH) from the pituitary gland (central DI) or the inability of the kidney tubules to respond to ADH (nephrogenic DI). ADH is an octapeptide produced in the supraoptic and paraventricular nuclei of the hypothalamus and stored in the posterior lobe of the pituitary gland. Cardiopulmonary Bypass (CPB) has been shown to cause a six-fold increased circulating ADH levels 12 hours after surgery. However, in some cases, ADH release may be transiently suppressed due to cardioplegia (cardiac standstill) or CPB leading to DI. We present the postoperative course of a 60-year-old man who developed transient DI after CPB. He was successfully treated by applying nasal desmopressin therapy. Relevant biochemical parameters should be monitored closely in patients who produce excessive urine after open heart surgery.

  12. Emergent cardiopulmonary bypass during pectus excavatum repair

    Directory of Open Access Journals (Sweden)

    Ryan Craner


    Full Text Available Pectus excavatum is a chest wall deformity that produces significant cardiopulmonary disability and is typically seen in younger patients. Minimally invasive repair of pectus excavatum or Nuss procedure has become a widely accepted technique for adult and pediatric patients. Although it is carried out through a thoracoscopic approach, the procedure is associated with a number of potential intraoperative and post-operative complications. We present a case of cardiac perforation requiring emergent cardiopulmonary bypass in a 29-year-old male with Marfan syndrome and previous mitral valve repair undergoing a Nuss procedure for pectus excavatum. This case illustrates the importance of vigilance and preparation by the surgeons, anesthesia providers as well as the institution to be prepared with resources to handle the possible complications. This includes available cardiac surgical backup, perfusionist support and adequate blood product availability.

  13. Impact of Norepinephrine on Regional Cerebral Oxygenation During Cardiopulmonary Bypass. (United States)

    Hagen, Ove Andreas; Høiseth, Lars Øivind; Roslin, André; Landsverk, Svein Aslak; Woldbaek, Per Reidar; Pripp, Are Hugo; Hanoa, Rolf; Kirkebøen, Knut Arvid


    Norepinephrine is used to increase mean arterial pressure during cardiopulmonary bypass. However, it has been suggested that norepinephrine could constrict cerebral arteries, reducing cerebral blood flow. The aim of this study, therefore, was to explore whether there was an association between doses of norepinephrine to maintain mean arterial pressure at ≈80 mmHg during cardiopulmonary bypass and cerebral oxygen saturation measured using near-infrared spectroscopy. Observational study. University hospital. Patients undergoing cardiac surgery (n = 45) using cardiopulmonary bypass. Norepinephrine was administered to maintain mean arterial pressure ≈80 mmHg during cardiopulmonary bypass. From initiation of cardiopulmonary bypass to removal of the aortic cross-clamp, norepinephrine dose, mean arterial pressure, partial pressure of arterial carbon dioxide, partial pressure of arterial oxygen, hemoglobin, and pump flow values were averaged over 1 minute, giving a total of 3,460 data points entered as covariates in a linear mixed model for repeated measurements, with cerebral oxygen saturation measured using near-infrared spectroscopy as outcome. There was no statistically significant association between norepinephrine dose to maintain mean arterial pressure and cerebral oxygen saturation (p = 0.46) in this model. Administration of norepinephrine to maintain mean arterial pressure ≈80 mmHg during cardiopulmonary bypass was not associated with statistically significant changes in cerebral oxygen saturation. These results indicated that norepinephrine could be used to increase mean arterial pressure during cardiopulmonary bypass without reducing cerebral oxygen saturation. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Ultrathin Nanostructured Metals for Highly Transmissive Plasmonic Subtractive Color Filters (United States)

    Zeng, Beibei; Gao, Yongkang; Bartoli, Filbert J.


    Plasmonic color filters employing a single optically-thick nanostructured metal layer have recently generated considerable interest as an alternative to colorant-based color filtering technologies, due to their reliability, ease of fabrication, and high color tunability. However, their relatively low transmission efficiency (~30%) needs to be significantly improved for practical applications. The present work reports, for the first time, a novel plasmonic subtractive color filtering scheme that exploits the counter-intuitive phenomenon of extraordinary low transmission (ELT) through an ultrathin nanostructured metal film. This approach relies on a fundamentally different color filtering mechanism than that of existing plasmonic additive color filters, and achieves unusually high transmission efficiencies of 60 ~ 70% for simple architectures. Furthermore, owing to short-range interactions of surface plasmon polaritons at ELT resonances, our design offers high spatial resolution color filtering with compact pixel size close to the optical diffraction limit (~λ/2), creating solid applications ranging from imaging sensors to color displays. PMID:24100869

  15. Choosing and using astronomical filters

    CERN Document Server

    Griffiths, Martin


    As a casual read through any of the major amateur astronomical magazines will demonstrate, there are filters available for all aspects of optical astronomy. This book provides a ready resource on the use of the following filters, among others, for observational astronomy or for imaging: Light pollution filters Planetary filters Solar filters Neutral density filters for Moon observation Deep-sky filters, for such objects as galaxies, nebulae and more Deep-sky objects can be imaged in much greater detail than was possible many years ago. Amateur astronomers can take

  16. Filters for cathodic arc plasmas (United States)

    Anders, Andre; MacGill, Robert A.; Bilek, Marcela M. M.; Brown, Ian G.


    Cathodic arc plasmas are contaminated with macroparticles. A variety of magnetic plasma filters has been used with various success in removing the macroparticles from the plasma. An open-architecture, bent solenoid filter, with additional field coils at the filter entrance and exit, improves macroparticle filtering. In particular, a double-bent filter that is twisted out of plane forms a very compact and efficient filter. The coil turns further have a flat cross-section to promote macroparticle reflection out of the filter volume. An output conditioning system formed of an expander coil, a straightener coil, and a homogenizer, may be used with the magnetic filter for expanding the filtered plasma beam to cover a larger area of the target. A cathodic arc plasma deposition system using this filter can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

  17. The Staphylococcus aureus FASII bypass escape route from FASII inhibitors. (United States)

    Morvan, Claire; Halpern, David; Kénanian, Gérald; Pathania, Amit; Anba-Mondoloni, Jamila; Lamberet, Gilles; Gruss, Alexandra; Gloux, Karine


    Antimicrobials targeting the fatty acid synthesis (FASII) pathway are being developed as alternative treatments for bacterial infections. Emergence of resistance to FASII inhibitors was mainly considered as a consequence of mutations in the FASII target genes. However, an alternative and efficient anti-FASII resistance strategy, called here FASII bypass, was uncovered. Bacteria that bypass FASII incorporate exogenous fatty acids in membrane lipids, and thus dispense with the need for FASII. This strategy is used by numerous Gram-positive low GC % bacteria, including streptococci, enterococci, and staphylococci. Some bacteria repress FASII genes once fatty acids are available, and "constitutively" shift to FASII bypass. Others, such as the major pathogen Staphylococcus aureus, can undergo high frequency mutations that favor FASII bypass. This capacity is particularly relevant during infection, as the host supplies the fatty acids needed for bacteria to bypass FASII and thus become resistant to FASII inhibitors. Screenings for anti-FASII resistance in the presence of exogenous fatty acids confirmed that FASII bypass confers anti-FASII resistance among clinical and veterinary isolates. Polymorphisms in S. aureus FASII initiation enzymes favor FASII bypass, possibly by increasing availability of acyl-carrier protein, a required intermediate. Here we review FASII bypass and consequences in light of proposed uses of anti-FASII to treat infections, with a focus on FASII bypass in S. aureus. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  18. Sensory pollution from bag filters, carbon filters and combinations. (United States)

    Bekö, G; Clausen, G; Weschler, C J


    Used ventilation filters are a major source of sensory pollutants in air handling systems. The objective of the present study was to evaluate the net effect that different combinations of filters had on perceived air quality after 5 months of continuous filtration of outdoor suburban air. A panel of 32 subjects assessed different sets of used filters and identical sets consisting of new filters. Additionally, filter weights and pressure drops were measured at the beginning and end of the operation period. The filter sets included single EU5 and EU7 fiberglass filters, an EU7 filter protected by an upstream pre-filter (changed monthly), an EU7 filter protected by an upstream activated carbon (AC) filter, and EU7 filters with an AC filter either downstream or both upstream and downstream. In addition, two types of stand-alone combination filters were evaluated: a bag-type fiberglass filter that contained AC and a synthetic fiber cartridge filter that contained AC. Air that had passed through used filters was most acceptable for those sets in which an AC filter was used downstream of the particle filter. Comparable air quality was achieved with the stand-alone bag filter that contained AC. Furthermore, its pressure drop changed very little during the 5 months of service, and it had the added benefit of removing a large fraction of ozone from the airstream. If similar results are obtained over a wider variety of soiling conditions, such filters may be a viable solution to a long recognized problem. The present study was designed to address the emission of sensory offending pollutants from loaded ventilation filters. The goal was to find a low-polluting solution from commercially available products. The results indicate that the use of activated carbon (AC) filters downstream of fiberglass bag filters can reduce the degradation of air quality that occurs with increasing particle loading. A more practical solution, yet comparably effective, is a stand-alone particle

  19. Multilevel ensemble Kalman filtering

    KAUST Repository

    Hoel, Haakon


    The ensemble Kalman filter (EnKF) is a sequential filtering method that uses an ensemble of particle paths to estimate the means and covariances required by the Kalman filter by the use of sample moments, i.e., the Monte Carlo method. EnKF is often both robust and efficient, but its performance may suffer in settings where the computational cost of accurate simulations of particles is high. The multilevel Monte Carlo method (MLMC) is an extension of classical Monte Carlo methods which by sampling stochastic realizations on a hierarchy of resolutions may reduce the computational cost of moment approximations by orders of magnitude. In this work we have combined the ideas of MLMC and EnKF to construct the multilevel ensemble Kalman filter (MLEnKF) for the setting of finite dimensional state and observation spaces. The main ideas of this method is to compute particle paths on a hierarchy of resolutions and to apply multilevel estimators on the ensemble hierarchy of particles to compute Kalman filter means and covariances. Theoretical results and a numerical study of the performance gains of MLEnKF over EnKF will be presented. Some ideas on the extension of MLEnKF to settings with infinite dimensional state spaces will also be presented.

  20. Multilevel Mixture Kalman Filter

    Directory of Open Access Journals (Sweden)

    Xiaodong Wang


    Full Text Available The mixture Kalman filter is a general sequential Monte Carlo technique for conditional linear dynamic systems. It generates samples of some indicator variables recursively based on sequential importance sampling (SIS and integrates out the linear and Gaussian state variables conditioned on these indicators. Due to the marginalization process, the complexity of the mixture Kalman filter is quite high if the dimension of the indicator sampling space is high. In this paper, we address this difficulty by developing a new Monte Carlo sampling scheme, namely, the multilevel mixture Kalman filter. The basic idea is to make use of the multilevel or hierarchical structure of the space from which the indicator variables take values. That is, we draw samples in a multilevel fashion, beginning with sampling from the highest-level sampling space and then draw samples from the associate subspace of the newly drawn samples in a lower-level sampling space, until reaching the desired sampling space. Such a multilevel sampling scheme can be used in conjunction with the delayed estimation method, such as the delayed-sample method, resulting in delayed multilevel mixture Kalman filter. Examples in wireless communication, specifically the coherent and noncoherent 16-QAM over flat-fading channels, are provided to demonstrate the performance of the proposed multilevel mixture Kalman filter.

  1. A novel rotary pulsatile flow pump for cardiopulmonary bypass. (United States)

    Teman, Nicholas R; Mazur, Daniel E; Toomasian, John; Jahangir, Emilia; Alghanem, Fares; Goudie, Marcus; Rojas-Peña, Alvaro; Haft, Jonathan W


    It has been suggested that pulsatile blood flow is superior to continuous flow (CF) in cardiopulmonary bypass (CPB). However, adoption of pulsatile flow (PF) technology has been limited because of practicality and complexity of creating a consistent physiologic pulse. A pediatric pulsatile rotary ventricular pump (PRVP) was designed to address this problem. We evaluated the PRVP in an animal model and determined its ability to generate PF during CPB. The PRVP (modified peristaltic pump, with tapering of the outlet of the pump chamber) was tested in four piglets (10-12 kg). Cannulation was performed with right atrial and aortic cannulae, and pressure sensors were inserted into the femoral arteries. Pressure curves were obtained at different levels of flow and compared with both the animal's baseline physiologic function and a CF roller pump. Pressure and flow waveforms demonstrated significant pulsatility in the PRVP setup compared with CF at all tested conditions. Measurement of hemodynamic energy data, including the percentage pulsatile energy and the surplus hydraulic energy, also revealed a significant increase in pulsatility with the PRVP (p < 0.001). The PRVP creates physiologically significant PF, similar to the pulsatility of a native heart, and has the potential to be easily implemented in pediatric CPB.

  2. Present state and future prospect of technology for semipermanent use of lubricating oil and zero wast oil; Junkatsuyu no han`eikyu shiyo/haiyu zero gijutsu no genjo to kongo no tenbo

    Energy Technology Data Exchange (ETDEWEB)

    Azuma, T. [Teikyo Univ., Tokyo (Japan) Sumimoto, M.] Kimura, K. [Sumimoto Science Research Inst., Yokohoma (Japan)


    `Kidney system`, technology for semipermanent use of lubricating oil in marine diesel engines and zero wast oil, has been developed. It is a purification system of keeping lubricating oil clean permanently. It has been actually used for marine main and auxiliary Diesel engines and co-generation Diesel engines. In this paper the purification system is outlined first with figures. Part of lubricating oil, circulating in engines, is by-passed to the nephron filter and continuously purified. The ability of the nephron filter is then described. The results in many fields, e.g. reducing lubricating oil consumption, improving engine reliability, keeping lubricating oil clean, and etc., are described. The development of a new flushing method for used engines is also introduced. The future prospect and problems to be solved are stated. 23 refs., 4 figs.

  3. Filters for Submillimeter Electromagnetic Waves (United States)

    Berdahl, C. M.


    New manufacturing process produces filters strong, yet have small, precise dimensions and smooth surface finish essential for dichroic filtering at submillimeter wavelengths. Many filters, each one essentially wafer containing fine metal grid made at same time. Stacked square wires plated, fused, and etched to form arrays of holes. Grid of nickel and tin held in brass ring. Wall thickness, thickness of filter (hole depth) and lateral hole dimensions all depend upon operating frequency and filter characteristics.

  4. New-generation stents compared with coronary bypass surgery for unprotected left main disease: A word of caution. (United States)

    Benedetto, Umberto; Taggart, David P; Sousa-Uva, Miguel; Biondi-Zoccai, Giuseppe; Di Franco, Antonino; Ohmes, Lucas B; Rahouma, Mohamed; Kamel, Mohamed; Caputo, Massimo; Girardi, Leonard N; Angelini, Gianni D; Gaudino, Mario


    With the advent of bare metal stents and drug-eluting stents, percutaneous coronary intervention has emerged as an alternative to coronary artery bypass grafting surgery for unprotected left main disease. However, whether the evolution of stents technology has translated into better results after percutaneous coronary intervention remains unclear. We aimed to compare coronary artery bypass grafting with stents of different generations for left main disease by performing a Bayesian network meta-analysis of available randomized controlled trials. All randomized controlled trials with at least 1 arm randomized to percutaneous coronary intervention with stents or coronary artery bypass grafting for left main disease were included. Bare metal stents and drug-eluting stents of first- and second-generation were compared with coronary artery bypass grafting. Poisson methods and Bayesian framework were used to compute the head-to-head incidence rate ratio and 95% credible intervals. Primary end points were the composite of death/myocardial infarction/stroke and repeat revascularization. Nine randomized controlled trials were included in the final analysis. Six trials compared percutaneous coronary intervention with coronary artery bypass grafting (n = 4654), and 3 trials compared different types of stents (n = 1360). Follow-up ranged from 6 months to 5 years. Second-generation drug-eluting stents (incidence rate ratio, 1.3; 95% credible interval, 1.1-1.6), but not bare metal stents (incidence rate ratio, 0.63; 95% credible interval, 0.27-1.4), and first-generation drug-eluting stents (incidence rate ratio, 0.85; 95% credible interval, 0.65-1.1) were associated with a significantly increased risk of death/myocardial infarction/stroke when compared with coronary artery bypass grafting. When compared with coronary artery bypass grafting, the highest risk of repeat revascularization was observed for bare metal stents (hazard ratio, 5.1; 95% confidence interval, 2

  5. A Study of Hydraulic Resistance of Viscous Bypass Gap in Magnetorheological Damper

    Directory of Open Access Journals (Sweden)

    Michal Kubík


    Full Text Available The paper presents hydraulic resistance of viscous bypass hole in magnetorheological damper. The suitable design of bypass hole is essential for efficient function of MR damper in automotive industry. In the paper analytical hydraulic model of bypass gap is compared with experiments. The commonly used hydraulic model of bypass gap does not agree with experiments.

  6. Off-pump versus on-pump coronary artery bypass grafting for ischaemic heart disease

    DEFF Research Database (Denmark)

    Møller, Christian H; Penninga, Luit; Wetterslev, Jørn


    Coronary artery bypass grafting (CABG) is performed both without and with cardiopulmonary bypass, referred to as off-pump and on-pump CABG respectively. However, the preferable technique is unclear.......Coronary artery bypass grafting (CABG) is performed both without and with cardiopulmonary bypass, referred to as off-pump and on-pump CABG respectively. However, the preferable technique is unclear....

  7. Asendan Desendan Aortic Bypass: Atan Kalpte Mediyan Sternotomi Yoluyla Onarim

    Directory of Open Access Journals (Sweden)

    Muhammet Akyuz


    Full Text Available We report the case of a 9-month-old patient presenting for redo aortic arch surgery because of recoarctation. In present case, ascending-to-descending aortic bypass via median sternotomy was performed without cardiopulmonary bypass with good result. In spite of the fact that the different surgical and intervention treatment options of aortic coarctation are quite satisfactory, a certain group of patients need reoperation because of recoarctation. The recoarctation repair of the aorta with the extra-anatomic aortic bypass is considered a low-risk procedure with high success rate.

  8. Adaptive digital filters

    CERN Document Server

    Kovačević, Branko; Milosavljević, Milan


    “Adaptive Digital Filters” presents an important discipline applied to the domain of speech processing. The book first makes the reader acquainted with the basic terms of filtering and adaptive filtering, before introducing the field of advanced modern algorithms, some of which are contributed by the authors themselves. Working in the field of adaptive signal processing requires the use of complex mathematical tools. The book offers a detailed presentation of the mathematical models that is clear and consistent, an approach that allows everyone with a college level of mathematics knowledge to successfully follow the mathematical derivations and descriptions of algorithms.   The algorithms are presented in flow charts, which facilitates their practical implementation. The book presents many experimental results and treats the aspects of practical application of adaptive filtering in real systems, making it a valuable resource for both undergraduate and graduate students, and for all others interested in m...

  9. Stack filter classifiers

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Reid B [Los Alamos National Laboratory; Hush, Don [Los Alamos National Laboratory


    Just as linear models generalize the sample mean and weighted average, weighted order statistic models generalize the sample median and weighted median. This analogy can be continued informally to generalized additive modeels in the case of the mean, and Stack Filters in the case of the median. Both of these model classes have been extensively studied for signal and image processing but it is surprising to find that for pattern classification, their treatment has been significantly one sided. Generalized additive models are now a major tool in pattern classification and many different learning algorithms have been developed to fit model parameters to finite data. However Stack Filters remain largely confined to signal and image processing and learning algorithms for classification are yet to be seen. This paper is a step towards Stack Filter Classifiers and it shows that the approach is interesting from both a theoretical and a practical perspective.

  10. Automated electronic filter design

    CERN Document Server

    Banerjee, Amal


    This book describes a novel, efficient and powerful scheme for designing and evaluating the performance characteristics of any electronic filter designed with predefined specifications. The author explains techniques that enable readers to eliminate complicated manual, and thus error-prone and time-consuming, steps of traditional design techniques. The presentation includes demonstration of efficient automation, using an ANSI C language program, which accepts any filter design specification (e.g. Chebyschev low-pass filter, cut-off frequency, pass-band ripple etc.) as input and generates as output a SPICE(Simulation Program with Integrated Circuit Emphasis) format netlist. Readers then can use this netlist to run simulations with any version of the popular SPICE simulator, increasing accuracy of the final results, without violating any of the key principles of the traditional design scheme.

  11. Linitis plastica of the bypassed stomach 7 years after Roux-en-Y gastric bypass: a case report. (United States)

    Haenen, Filip Wn; Gys, Ben; Moreels, Tom; Michielsen, Maartje; Gys, Tobie; Lafullarde, Thierry


    Laparoscopic Roux-en-Y gastric bypass (RYGB) is currently the preferred surgical procedure to treat morbid obesity. It has proven its effects on excess weight loss and its positive effect on comorbidities. One of the main issues, however, is the post-operative evaluation of the bypassed gastric remnant. In literature, cancer of the excluded stomach after RYGB is rare. We describe the case of a 52-year-old woman with gastric linitis plastica in the bypassed stomach after Roux-en-Y gastric bypass, diagnosed by means of laparoscopy and Single-Balloon enteroscopy, and it is clinical importance. Linitis plastica of the excluded stomach after RYGB is a very rare entity. This case report shows the importance of long-term post-operative follow-up, and the importance of single-balloon enteroscopy for visualization of the bypassed stomach remnant, when other investigations remain without results. This case report is only the second report of a linitis plastica in the bypassed stomach after Roux-en-Y gastric bypass.

  12. Healthcare failure mode effect analysis of a miniaturized extracorporeal bypass circuit. (United States)

    Overdevest, Ep; van Hees, Jwh; Lagerburg, V; Kloeze, C; van Straten, Ahm


    The introduction of new and more advanced technology in healthcare occurs with an increasing speed. Therefore, more attention is needed for safety evaluation of new devices or techniques from an end-user perspective, especially when (inter-) national perfusion safety standards are lacking. A recently increased awareness of the safety risks as a consequence of technical or human error has provoked interest in optimisation of perfusion methodology and devices. To prevent or reduce the severity or likelihood of failures of new technology, 'failure mode effect analysis' is a proven proactive technique. When it is used as a qualitative analysis for possible hazards in patient treatment associated with the use of medical devices, it's called healthcare failure mode effect analysis (hFMEA). To evaluate the safety of the Extra Corporeal Circulation Optimized (ECCO, Sorin Group, Mirandola, Italy) miniaturized bypass circuit, hFMEA was used. A multi disciplinary team that consisted of two clinical perfusionists, a clinical physicist, a clinical physicist trainee and a technician has performed this analysis. The hFMEA demonstrated that failure of the bubble sensor for the electric remote clamping system on the arterial line (Figure 1), activated by air passing the venous bubble trap, had the highest risk score of all failure modes. This has led to the implementation of an extra low-level sensor in the system to prevent air passing through into the centrifugal pump. The hFMEA has also indicated that extra individual simulation training is needed for handling critical failures during the use of the miniature bypass system. Early identification of possible technology failures in any process or device can avoid adverse patient outcomes. The technique of hFMEA is a valuable tool in evaluating the use of high-risk apparatus, such as an extracorporeal bypass system, in patient treatment in order to increase patient safety. © The Author(s) 2014.

  13. Filters in topology optimization

    DEFF Research Database (Denmark)

    Bourdin, Blaise


    In this article, a modified (``filtered'') version of the minimum compliance topology optimization problem is studied. The direct dependence of the material properties on its pointwise density is replaced by a regularization of the density field using a convolution operator. In this setting...... it is possible to establish the existence of solutions. Moreover, convergence of an approximation by means of finite elements can be obtained. This is illustrated through some numerical experiments. The ``filtering'' technique is also shown to cope with two important numerical problems in topology optimization...

  14. A PC Controlled Filter

    Directory of Open Access Journals (Sweden)

    M. Van Looy


    Full Text Available In this paper we present a switched capacitor filter design using the SC22324 1C, which is fitted with an E2PROM. It contains four digitally programmable switched-capacitor filter sections, in order to obtain different responses. The SC22324 also contains the on-chip RAM. We'd like to explain, how could the on-chip RAM controlled via a PC. In this way the chip may be used afterwards with a menu where the user may select the wanted parameters.

  15. Parzen Particle Filters

    DEFF Research Database (Denmark)

    Lehn-Schiøler, Tue; Erdogmus, Deniz; Principe, Jose C.


    Using a Parzen density estimator any distribution can be approximated arbitrarily close by a sum of kernels. In particle filtering this fact is utilized to estimate a probability density function with Dirac delta kernels; when the distribution is discretized it becomes possible to solve an otherw......Using a Parzen density estimator any distribution can be approximated arbitrarily close by a sum of kernels. In particle filtering this fact is utilized to estimate a probability density function with Dirac delta kernels; when the distribution is discretized it becomes possible to solve...

  16. DC-pass filter design with notch filters superposition for CPW rectenna at low power level (United States)

    Rivière, J.; Douyère, A.; Alicalapa, F.; Luk, J.-D. Lan Sun


    In this paper the challenging coplanar waveguide direct current (DC) pass filter is designed, analysed, fabricated and measured. As the ground plane and the conductive line are etched on the same plane, this technology allows the connection of series and shunt elements to the active devices without via holes through the substrate. Indeed, this study presents the first step in the optimization of a complete rectenna in coplanar waveguide (CPW) technology: key element of a radio frequency (RF) energy harvesting system. The measurement of the proposed filter shows good performance in the rejection of F0=2.45 GHz and F1=4.9 GHz. Additionally, a harmonic balance (HB) simulation of the complete rectenna is performed and shows a maximum RF-to-DC conversion efficiency of 37% with the studied DC-pass filter for an input power of 10 µW at 2.45 GHz.

  17. Treatment of Wastewater from Backwashing Process Sand Filters

    Directory of Open Access Journals (Sweden)

    Miletić, S.


    Full Text Available In the process of raw water treatment for use in the petrochemical industry, one of the most important treatments is the filtration process with process sand filters. A by-product of the filtration process of raw water is wastewater. The wastewater results from the technological process of backwashing process sand filters. Wastewater from backwashing sand filters is unsuitable for further use, since it is contaminated with residual suspended matter and chemical compounds that are added in the process of raw water clarification. To reduce the environmental impact of such wastewater and improve overall system processing of raw water, this paper presents the technological treatment of wastewater from backwashing process sand filters. The selected technological process with subsequent sedimentation of suspended matter from the wastewater enables it to be returned into the process stream. This paper also presents a wastewater treatment system, which consists of a concrete sedimentation tank, pumps, pipelines, and flocculator for the final acceptance of the wastewater. The treatment system of wastewater from backwashing process sand filters includes the wastewater from backwashing sand filters for the filtration of the clarified water after clarification of the raw water, sand filters for the filtration of the cooling water and sand filters for filtration of clarified water prior to ion decarbonatisation. The overall technological process is efficiently sized and fully automated. The treatment of wastewater from backwashing process sand filters allows the successful and continuous return of the water in a volume flow, Q, from 80 m3h-1 to 85 m3 h-1, with no negative impact on the clarification of raw water. The constructed technological solution resulted in 12-percent less use of raw water from the Pakra accumulation lake, as well as 50-percent less discharge of the wastewater into natural watercourses.

  18. Varactor-tuned Substrate Integrated Evanescent Filter

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Acar, Öncel; Dong, Yunfeng

    Evanescent mode waveguides allow for more compact microwave component design in comparison to the traditional fundamental mode waveguide technology. Evanescent waveguides can be integrated into a dielectric substrate in order to further reduce the mass and volume. Unfortunately, traditional reali......, fabricated and tested in order to validate the developed filter models as well as the implemented realization method. The filter structure as well as its tuning are shown in Figure 1....... is considered. In contrast to other methods described in the literature, it avoids etching split ring resonators in the metal layer of the SIW. The filters presented here use varactors as tuning elements. The varactors (as well as DC decoupling circuits) are mounted on the surface of PCB bringing the lower...... metal layer of the waveguide to the top layer with metalized via holes. The present filters are analyzed using models based on impedance matrix representation. The developed models allow computationally efficient and relatively accurate prediction of the filter behavior in a wide frequency range (at...

  19. Renal tubular acidosis secondary to jejunoileal bypass for morbid obesity

    DEFF Research Database (Denmark)

    Schaffalitzky de Muckadell, O B; Ladefoged, Jens; Thorup, Jørgen Mogens


    Renal handling of acid and base was studied in patients with persistent metabolic acidosis 3-9 years after jejunoileal bypass for morbid obesity. Excretion of acid was studied before and after intravenous infusion of NH4Cl and excretion of bicarbonate after infusion of NaHCO3. Bypass patients...... showed impaired capacity for acidification of urine. The lowest urinary pH was 5.53 +/- 0.10 in 10 bypass patients and 4.76 +/- 0.06 in 6 controls. The corresponding values for standard bicarbonate in plasma were 15.0 +/- 0.3 mM and 15.8 +/- 0.3 mM. Glomerular filtration rate was identical in the two...... groups. Fractional loss of bicarbonate in urine was higher in controls than in bypass patients. The renal impairment is classified as distal renal tubular acidosis....

  20. Evaluation of bypass lane safety, operations, and design in Kansas. (United States)


    The construction of bypass lanes at rural intersections has typically been considered a low-cost highway safety : improvement by the transportation community. However, this needs to be quantitatively evaluated so that decisions can be made : on wheth...

  1. Antiplatelet therapy at the time of coronary artery bypass grafting

    DEFF Research Database (Denmark)

    Kremke, Michael; Jensen, Mariann Tang; Bak, Mikkel


    OBJECTIVES: The purpose of this multicentre cohort study was to examine the relationship between antiplatelet therapy (APT) at the time of coronary artery bypass grafting (CABG) and postoperative bleeding complications, transfusion requirements and adverse cardiovascular events. METHODS: A matched...

  2. Subarachnoid-subarachnoid bypass for spinal adhesive arachnoiditis. (United States)

    Tachibana, Toshiya; Moriyama, Tokuhide; Maruo, Keishi; Inoue, Shinichi; Arizumi, Fumihiro; Yoshiya, Shinichi


    The authors report a case of adhesive arachnoiditis (AA) and arachnoid cyst successfully treated by subarachnoid to subarachnoid bypass (S-S bypass). Arachnoid cysts or syringes sometimes compress the spinal cord and cause compressive myelopathy that requires surgical treatment. However, surgical treatment for AA is challenging. A 57-year-old woman developed leg pain and gait disturbance. A dorsal arachnoid cyst compressed the spinal cord at T7-9, the spinal cord was swollen, and a small syrinx was present at T9-10. An S-S bypass was performed from T6-7 to T11-12. The patient's gait disturbance resolved immediately after surgery. Two years later, a small arachnoid cyst developed. However, there was no neurological deterioration. The myelopathy associated with thoracic spinal AA, subarachnoid cyst, and syrinx improved after S-S bypass.

  3. Rodent models of cardiopulmonary bypass: utility in improving perioperative outcomes

    NARCIS (Netherlands)

    de Lange, F.


    Despite advances in surgical and anesthesia techniques, subtle neurologic injury still remains an important complication after cardiac surgery. Because the causes are multifactorial and complex, research in an appropriate small animal model for cardiopulmonary bypass (CPB) is warranted. This thesis

  4. Stressors and anxiety in patients undergoing coronary artery bypass surgery

    National Research Council Canada - National Science Library

    Gallagher, Robyn; McKinley, Sharon


    Patients undergoing coronary artery bypass surgery who have increased anxiety levels have poorer outcomes than patients with lower levels, yet few studies have identified the concerns associated with this anxiety...

  5. Enhanced Optical Filter Design

    CERN Document Server

    Cushing, David


    This book serves as a supplement to the classic texts by Angus Macleod and Philip Baumeister, taking an intuitive approach to the enhancement of optical coating (or filter) performance. Drawing from 40 years of experience in thin film design, Cushing introduces the basics of thin films, the commonly used materials and their deposition, the major coatings and their applications, and improvement methods for each.

  6. The ATLAS event filter

    CERN Document Server

    Beck, H P; Boissat, C; Davis, R; Duval, P Y; Etienne, F; Fede, E; Francis, D; Green, P; Hemmer, F; Jones, R; MacKinnon, J; Mapelli, Livio P; Meessen, C; Mommsen, R K; Mornacchi, Giuseppe; Nacasch, R; Negri, A; Pinfold, James L; Polesello, G; Qian, Z; Rafflin, C; Scannicchio, D A; Stanescu, C; Touchard, F; Vercesi, V


    An overview of the studies for the ATLAS Event Filter is given. The architecture and the high level design of the DAQ-1 prototype is presented. The current status if the prototypes is briefly given. Finally, future plans and milestones are given. (11 refs).

  7. Fast Anisotropic Gauss Filters

    NARCIS (Netherlands)

    Geusebroek, J.M.; Smeulders, A.W.M.; van de Weijer, J.


    We derive the decomposition of the anisotropic Gaussian in a one dimensional Gauss filter in the x-direction phi. So also the anisotropic Gaussian can be decomposed by dimension. This appears to be extremely efficient from a computing perspective. An implementation scheme for normal covolution and

  8. Underwater Sound Filtering

    NARCIS (Netherlands)

    Rutger van Aalst; Ines Simic


    This paper describes a possible solution to the underwater sound filtering problem, using Blind Source Separation. The problem regards splitting sound from a boat engine and the water waves to prove the possibility to extract one sound fragment from the other on the open sea. The illustrations shown

  9. Transfusion requirements in elective cardiopulmonary bypass surgery patients

    DEFF Research Database (Denmark)

    Sivapalan, Praleene; Bäck, Anne Caroline; Ostrowski, Sisse Rye


    Managing haemostasis in patients undergoing cardiopulmonary bypass (CPB) surgery remains a challenge. There is no established laboratory test to predict transfusion requirements in cardiac surgery. We investigated whether preoperative Thromboelastography (TEG) with Platelet Mapping Assay (PMA......) or Multiple Electrode Aggrometry (MEA) could predict transfusion requirements in patients undergoing elective coronary artery bypass grafting (CABG) or combined CABG with aortic or mitral valve replacement. We prospectively investigated 199 patients undergoing elective CABG or combined procedures. PMA and MEA...

  10. Hypoparathyroidism after total thyroidectomy in patients with previous gastric bypass. (United States)

    Droeser, Raoul A; Ottosson, Johan; Muth, Andreas; Hultin, Hella; Lindwall-Åhlander, Karin; Bergenfelz, Anders; Almquist, Martin


    Case reports suggest that patients with previous gastric bypass have an increased risk of severe hypocalcemia after total thyroidectomy, but there are no population-based studies. The prevalence of gastric bypass before thyroidectomy and the risk of hypocalcemia after thyroidectomy in patients with previous gastric bypass were investigated. By cross-linking The Scandinavian Quality Registry for Thyroid, Parathyroid and Adrenal Surgery with the Scandinavian Obesity Surgery Registry patients operated with total thyroidectomy without concurrent or previous surgery for hyperparathyroidism were identified and grouped according to previous gastric bypass. The risk of treatment with intravenous calcium during hospital stay, and with oral calcium and vitamin D at 6 weeks and 6 months postoperatively was calculated by using multiple logistic regression in the overall cohort and in a 1:1 nested case-control analysis. We identified 6115 patients treated with total thyroidectomy. Out of these, 25 (0.4 %) had undergone previous gastric bypass surgery. In logistic regression, previous gastric bypass was not associated with treatment with i.v. calcium (OR 2.05, 95 % CI 0.48-8.74), or calcium and/or vitamin D at 6 weeks (1.14 (0.39-3.35), 1.31 (0.39-4.42)) or 6 months after total thyroidectomy (1.71 (0.40-7.32), 2.28 (0.53-9.75)). In the nested case-control analysis, rates of treatment for hypocalcemia were similar in patients with and without previous gastric bypass. Previous gastric bypass surgery was infrequent in patients undergoing total thyroidectomy and was not associated with an increased risk of postoperative hypocalcemia.

  11. Association of sex with patency of femorodistal bypass grafts

    DEFF Research Database (Denmark)

    Watson, H R; Schroeder, T V; Simms, M H


    There is evidence for superior patency in infra-inguinal bypass procedures in men compared to women. A large, prospectively planned series was investigated in order to confirm this finding and to determine the origin of this difference in outcome.......There is evidence for superior patency in infra-inguinal bypass procedures in men compared to women. A large, prospectively planned series was investigated in order to confirm this finding and to determine the origin of this difference in outcome....

  12. Pharmacological Bypass of Cockayne Syndrome B Function in Neuronal Differentiation


    Wang, Yuming; Jones-Tabah, Jace; Chakravarty, Probir; Stewart, Aengus; Muotri, Alysson; Laposa, Rebecca?R.; Svejstrup, Jesper?Q.


    Summary Cockayne syndrome (CS) is a severe neurodevelopmental disorder characterized by growth abnormalities, premature aging, and photosensitivity. Mutation of Cockayne syndrome B (CSB) affects neuronal gene expression and differentiation, so we attempted to bypass its function by expressing downstream target genes. Intriguingly, ectopic expression of Synaptotagmin 9 (SYT9), a key component of the machinery controlling neurotrophin release, bypasses the need for CSB in neuritogenesis. Import...

  13. Cancer Incidence and Mortality After Gastric Bypass Surgery


    Adams, Ted D.; Stroup, Antoinette M.; Gress, Richard E.; Adams, Kenneth F.; Calle, Eugenia E; Smith, Sherman C.; Halverson, R. Chad; Simper, Steven C.; Hopkins, Paul N; Hunt, Steven C.


    Despite weight loss recommendations to prevent cancer, cancer outcome studies after intentional weight loss are limited. Recently, reduced cancer mortality following bariatric surgery has been reported. This study tested whether reduced cancer mortality following gastric bypass was due to decreased incidence. Cancer incidence and mortality data through 2007 from the Utah Cancer Registry (UCR) were compared between 6,596 Utah patients who had gastric bypass (1984–2002) and 9,442 severely obese...

  14. Boundary-Layer Bypass Transition Over Large-Scale Bodies (United States)


    AFRL-AFOSR-UK-TR-2017-0007 Boundary - layer bypass transition over large-scale bodies Pierre Ricco UNIVERSITY OF SHEFFIELD, DEPARTMENT OF PSYCHOLOGY...REPORT TYPE Final 3. DATES COVERED (From - To) 01 Sep 2013 to 31 Aug 2016 4. TITLE AND SUBTITLE Boundary - layer bypass transition over large-scale...shape of the streamwise velocity profile compared to the flat-plate boundary layer . The research showed that the streamwise wavenumber plays a key role

  15. Combined coronary artery bypass surgery and abdominal aortic aneurysm repair.


    Black, J J; Desai, J B


    The proper management of patients with asymptomatic abdominal aortic aneurysms and significant coexistent coronary artery disease is still debatable. The most common approach has been to perform the coronary artery bypass surgery some weeks before the abdominal aortic aneurysm repair in the hope of reducing the cardiac morbidity and mortality. We report our initial experience of three consecutive elective cases where the coronary artery bypass surgery and the abdominal aortic aneurysm repair ...

  16. Robotically assisted totally endoscopic coronary artery bypass surgery


    Canale, Leonardo Secchin; Mick, Stephanie; Mihaljevic, Tomislav; Nair, Ravi; Bonatti, Johannes


    Robotically assisted totally endoscopic coronary artery bypass surgery has emerged as a feasible and efficient alternative to conventional full sternotomy coronary artery bypass graft surgery in selected patients. This minimally invasive approach using the daVinci robotic system allows fine intrathoracic maneuvers and excellent view of the coronary arteries. Both on-pump and off-pump operations can be performed to treat single and multivessel disease. Hybrid approaches have the potential of o...

  17. One-dimensional Arterial Network Model for Bypass Grafts Assessment

    CERN Document Server

    Ghigo, Arthur; Wang, Xiaofei; Lagrée, Pierre-Yves; Fullana, Jose-Maria


    We propose an arterial network model based on 1D blood hemodynamic equations to study the behavior of different vascular surgical bypass grafts in case of an arterial occlusive pathology: an obliteration or stenosis of the iliac artery. We investigate the performances of three different bypass grafts (Aorto-Femoral, Axillo-Femoral and cross-over Femoral) depending on the degree of obliteration of the stenosis. Numerical simulations show that all bypass grafts are efficient since we retrieve in all cases the normal hemodynamics in the stenosed region while ensuring at the same time a global healthy circulation. We analyze in particular the Axillo-Femoral bypass graft by performing hundreds of simulations by varying the values of the Young's modulus [0.1--50 MPa] and the radius [0.01--5 cm] of the bypass graft. We show that the Young's modulus and radius of commercial bypass grafts are optimal in terms of hemodynamic considerations. The numerical findings prove that this approach could be used to optimize or pl...

  18. Progress on Complications of Direct Bypass for Moyamoya Disease. (United States)

    Yu, Jinlu; Shi, Lei; Guo, Yunbao; Xu, Baofeng; Xu, Kan


    Moyamoya disease (MMD) involves progressive occlusion of the intracranial internal carotid artery resulting in formation of moyamoya-like vessels at the base of the brain. It can be characterized by hemorrhage or ischemia. Direct vascular bypass is the main and most effective treatment of MMD. However, patients with MMD differ from those with normal cerebral vessels. MMD patients have unstable intracranial artery hemodynamics and a poor blood flow reserve; therefore, during the direct bypass of superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis, perioperative risk factors and anesthesia can affect the hemodynamics of these patients. When brain tissue cannot tolerate a high blood flow rate, it becomes prone to hyperperfusion syndrome, which leads to neurological function defects and can even cause intracranial hemorrhage in severe cases. The brain tissue is prone to infarction when hemodynamic equilibrium is affected. In addition, bypass vessels become susceptible to occlusion or atrophy when blood resistance increases. Even compression of the temporalis affects bypass vessels. Because the STA is used in MMD surgery, the scalp becomes ischemic and is likely to develop necrosis and infection. These complications of MMD surgery are difficult to manage and are not well understood. To date, no systematic studies of the complications that occur after direct bypass in MMD have been performed, and reported complications are hidden among various case studies; therefore, this paper presents a review and summary of the literature in PubMed on the complications of direct bypass in MMD.

  19. Variations in dietary intake after bypass surgery for obesity. Possible relation to development of fatty liver after jejunoileal bypass

    Energy Technology Data Exchange (ETDEWEB)

    Rogus, J.; Blumenthal, S.A.


    Consumption of nutrients and food energy was compared, with concomitant chemical and radiologic measurements of hepatic fat content, preoperatively and postoperatively in 25 patients who underwent gastric or jejunoileal bypass for obesity. Patients in the two operative groups ingested similar quantities of food before surgery. After surgery, caloric intake from all sources decreased in both groups but to a significantly greater extent in the gastric bypass patients. During the first six months postoperatively, the 13 gastric bypass patients showed no changes in hepatic fat content, whereas substantial increases in liver fat uniformly occurred in the 12 patients who had jejunoileal bypasses. It is suggested that dietary carbohydrate may have contributed to the accretion of liver fat in these 12 patients.

  20. Numerical study of canister filters with alternatives filter cap configurations (United States)

    Mohammed, A. N.; Daud, A. R.; Abdullah, K.; Seri, S. M.; Razali, M. A.; Hushim, M. F.; Khalid, A.


    Air filtration system and filter play an important role in getting a good quality air into turbo machinery such as gas turbine. The filtration system and filter has improved the quality of air and protect the gas turbine part from contaminants which could bring damage. During separation of contaminants from the air, pressure drop cannot be avoided but it can be minimized thus helps to reduce the intake losses of the engine [1]. This study is focused on the configuration of the filter in order to obtain the minimal pressure drop along the filter. The configuration used is the basic filter geometry provided by Salutary Avenue Manufacturing Sdn Bhd. and two modified canister filter cap which is designed based on the basic filter model. The geometries of the filter are generated by using SOLIDWORKS software and Computational Fluid Dynamics (CFD) software is used to analyse and simulates the flow through the filter. In this study, the parameters of the inlet velocity are 0.032 m/s, 0.063 m/s, 0.094 m/s and 0.126 m/s. The total pressure drop produce by basic, modified filter 1 and 2 is 292.3 Pa, 251.11 Pa and 274.7 Pa. The pressure drop reduction for the modified filter 1 is 41.19 Pa and 14.1% lower compared to basic filter and the pressure drop reduction for modified filter 2 is 17.6 Pa and 6.02% lower compared to the basic filter. The pressure drops for the basic filter are slightly different with the Salutary Avenue filter due to limited data and experiment details. CFD software are very reliable in running a simulation rather than produces the prototypes and conduct the experiment thus reducing overall time and cost in this study.

  1. FPGA implementation of filtered image using 2D Gaussian filter


    Leila kabbai; Anissa Sghaier; Ali Douik; Mohsen Machhout


    Image filtering is one of the very useful techniques in image processing and computer vision. It is used to eliminate useless details and noise from an image. In this paper, a hardware implementation of image filtered using 2D Gaussian Filter will be present. The Gaussian filter architecture will be described using a different way to implement convolution module. Thus, multiplication is in the heart of convolution module, for this reason, three different ways to implement multiplication opera...

  2. NEMS-based MIM plasmonics tunable filter (United States)

    Khirallah, Kareem; Swillam, Mohamed A.


    Designing a miniaturized and efficient optical filter which can be actively tuned is a modern engineering challenge. This paper propose a design of a device with a nano scale size for active tuning the resonance frequency of a metal-insulator-metal plasmonics optical filter. The design is based on controlling the relative position between two stubs in metal-Insulator-metal plasmonics waveguide using NEMS technology. The mechanical design parameter is chosen carefully to be compatible with modern fabrication technology and a reasonable fabrication process of the device is proposed. The analysis of the mechanical and optical design is done and shows a promising performance. For the chosen mechanical design parameters, the optical resonance wavelength can be tuned from 1.45μm to 1.65μm using 7VDC actuation voltage.

  3. Generalized Selection Weighted Vector Filters

    Directory of Open Access Journals (Sweden)

    Rastislav Lukac


    Full Text Available This paper introduces a class of nonlinear multichannel filters capable of removing impulsive noise in color images. The here-proposed generalized selection weighted vector filter class constitutes a powerful filtering framework for multichannel signal processing. Previously defined multichannel filters such as vector median filter, basic vector directional filter, directional-distance filter, weighted vector median filters, and weighted vector directional filters are treated from a global viewpoint using the proposed framework. Robust order-statistic concepts and increased degree of freedom in filter design make the proposed method attractive for a variety of applications. Introduced multichannel sigmoidal adaptation of the filter parameters and its modifications allow to accommodate the filter parameters to varying signal and noise statistics. Simulation studies reported in this paper indicate that the proposed filter class is computationally attractive, yields excellent performance, and is able to preserve fine details and color information while efficiently suppressing impulsive noise. This paper is an extended version of the paper by Lukac et al. presented at the 2003 IEEE-EURASIP Workshop on Nonlinear Signal and Image Processing (NSIP '03 in Grado, Italy.

  4. Cardiopulmonary bypass increases the risk of vasoplegic syndrome after coronary artery bypass grafting in patients with dialysis-dependent chronic renal failure. (United States)

    Hossne Junior, Nelson Américo; Miranda, Matheus; Monteiro, Marcus Rodrigo; Branco, João Nelson Rodrigues; Vargas, Guilherme Flora; Pestana, José Osmar Medina de Abreu; Gomes, Walter José


    Coronary artery bypass grafting is currently the best treatment for dialysis patients with multivessel coronary artery involvement. Vasoplegic syndrome of inflammatory etiology constitutes an important postoperative complication, with highly negative impact on prognosis. Considering that these patients have an intrinsic inflammatory response exacerbation, our goal was to evaluate the incidence and mortality of vasoplegic syndrome after myocardial revascularization in this group. A retrospective, single-center study of 50 consecutive and non-selected dialysis patients who underwent myocardial revascularization in a tertiary university hospital, from 2007 to 2012. The patients were divided into 2 groups, according to the use of cardiopulmonary bypass or not (off-pump coronary artery bypass). The incidence and mortality of vasoplegic syndrome were analyzed. The subgroup of vasoplegic patients was studied separately. There were no preoperative demographic differences between the cardiopulmonary bypass (n=20) and off-pump coronary artery bypass (n=30) group. Intraoperative data showed a greater number of distal coronary arteries anastomosis (2.8 vs. 1.8, Pcardiopulmonary bypass group. Vasoplegia incidence was statistically higher (P=0.0124) in the cardiopulmonary bypass group (30%) compared to the off-pump coronary artery bypass group (3%). Vasoplegia mortality was 50% in the cardiopulmonary bypass group and 0% in the off-pump coronary artery bypass group. The vasoplegic subgroup analysis showed no statistically significant clinical differences. Cardiopulmonary bypass increased the risk for developing postoperative vasoplegic syndrome after coronary artery bypass grafting in patients with dialysis-dependent chronic renal failure.

  5. Coronary artery bypass grafting in octogenarians. (United States)

    Sakamoto, S; Matsubara, J; Matsubara, T; Nagayoshi, Y; Nishizawa, H; Shouno, S; Kouno, M; Takeuchi, K; Nonaka, T


    Preoperative profiles, postoperative complications, and the early and late results in 32 patients 80 yrs. of age and older (elderly group) who underwent coronary artery bypass grafting were compared with those in patients under 80 yrs. of age (control group). In the elderly group, the prevalence of patients with preoperative creatinine clearance (Ccr.) <50 l/day (34.4%), unstable angina pectoris (78.1%) and left main trunk disease (40.1%) was significantly higher than those in the control group. The incidences of arrhythmia and intensive care unit(ICU) syndrome were also significantly higher in the elderly group than in the control group, however, there was no death due to these complications. In the elderly group, one patient (3.1%) died in the hospital due to low cardiac output syndrome (LOS), while three patients (2.4%) of the control group died in the hospital. As for the long-term results, the 5-yr. survival rates for the elderly group and the control group were 82.6% and 85.2%, respectively, and the effectiveness of surgery was remarkable, with improved postoperative activity in 96.9% of the elderly group. These findings indicate that although the elderly patients have higher risks by undergoing surgery and have a disadvantage in the rate of postoperative complications, the postoperative improvement in activity and survival rate can be similar to those in the younger patients.

  6. Stabilizing family life after gastric bypass surgery. (United States)

    Bylund, Ami; Benzein, Eva; Sandgren, Anna


    Weight-loss surgery requires lifelong lifestyle modifications for the maintenance of weight loss and health effects, and can affect both the individual and family. Earlier research indicates that the quality of social relationships has positive and negative influences on wellbeing and health. There is little research on family-life after a member has undergone gastric bypass (GBP) against obesity. Thus, this study aimed to develop a classic grounded theory about families with a member treated with GBP against obesity. The study design used classic grounded theory and included data from 16 interviews. Families' shared a main concern of unexpected changes after GBP, resulting in the theory Stabilizing family life, explained as a social process to decrease uncertainty and find stability and well-being in family interactions. The social process develops differently which entail families: attaining unity, returning to old patterns, or disconnecting to find stability, depending on the discrepancy in expectations and knowledge. This is affected by the overall life situation, life-stage and relationship quality. The theory highlights unexpected change as a potential challenge for the family, as well as how they resolve this. Hence, the theory can be applied in care strategies for families. Identification of families needing support to stabilize family life after GBP requires further research.

  7. Cardiopulmonary bypass and edema: physiology and pathophysiology. (United States)

    Hirleman, E; Larson, D F


    Edema is a common morbidity following cardiopulmonary bypass (CPB) and can result in injury to many organs, including the heart, lungs, and brain. Generalized edema is also common and can lead to increased post-operative hospital stay and other morbidities. Pediatric patients are more susceptible to post-CPB edema and the consequences are more severe for this population. Hemodilution and systemic inflammatory responses are two suspected causes of CPB-related edema; however, the mechanisms involved are far from understood. Also, the common strategies to improve edema have not been completely successful and there is a need for new strategies at maintaining a fluid balance of patients as close to physiological as possible, especially for pediatric patients. An integrative approach to understanding edema is necessary as the forces involved in fluid homeostasis are dynamic and interdependent. Therefore, this review will focus on the physiology of fluid homeostasis and the pathologies of fluid shifts during CPB which lead to general edema as well as tissue-specific edema.

  8. Hydrodynamics of microbial filter feeding

    DEFF Research Database (Denmark)

    Nielsen, Lasse Tor; Asadzadeh, Seyed Saeed; Dölger, Julia


    Microbial filter feeders are an important group of grazers, significant to the microbial loop, aquatic food webs, and biogeochemical cycling. Our understanding of microbial filter feeding is poor, and, importantly, it is unknown what force microbial filter feeders must generate to process adequate...... amounts of water. Also, the trade-off in the filter spacing remains unexplored, despite its simple formulation: A filter too coarse will allow suitably sized prey to pass unintercepted, whereas a filter too fine will cause strong flow resistance. We quantify the feeding flow of the filter......-feeding choanoflagellate Diaphanoeca grandis using particle tracking, and demonstrate that the current understanding of microbial filter feeding is inconsistent with computational fluid dynamics (CFD) and analytical estimates. Both approaches underestimate observed filtration rates by more than an order of magnitude...

  9. Analog filters in nanometer CMOS

    CERN Document Server

    Uhrmann, Heimo; Zimmermann, Horst


    Starting from the basics of analog filters and the poor transistor characteristics in nanometer CMOS 10 high-performance analog filters developed by the authors in 120 nm and 65 nm CMOS are described extensively. Among them are gm-C filters, current-mode filters, and active filters for system-on-chip realization for Bluetooth, WCDMA, UWB, DVB-H, and LTE applications. For the active filters several operational amplifier designs are described. The book, furthermore, contains a review of the newest state of research on low-voltage low-power analog filters. To cover the topic of the book comprehensively, linearization issues and measurement methods for the characterization of advanced analog filters are introduced in addition. Numerous elaborate illustrations promote an easy comprehension. This book will be of value to engineers and researchers in industry as well as scientists and Ph.D students at universities. The book is also recommendable to graduate students specializing on nanoelectronics, microelectronics ...

  10. The Rao-Blackwellized Particle Filter: A Filter Bank Implementation

    Directory of Open Access Journals (Sweden)

    Karlsson Rickard


    Full Text Available For computational efficiency, it is important to utilize model structure in particle filtering. One of the most important cases occurs when there exists a linear Gaussian substructure, which can be efficiently handled by Kalman filters. This is the standard formulation of the Rao-Blackwellized particle filter (RBPF. This contribution suggests an alternative formulation of this well-known result that facilitates reuse of standard filtering components and which is also suitable for object-oriented programming. Our RBPF formulation can be seen as a Kalman filter bank with stochastic branching and pruning.

  11. Multilevel particle filter

    KAUST Repository

    Law, Kody


    This talk will pertain to the filtering of partially observed diffusions, with discrete-time observations. It is assumed that only biased approximations of the diffusion can be obtained, for choice of an accuracy parameter indexed by l. A multilevel estimator is proposed, consisting of a telescopic sum of increment estimators associated to the successive levels. The work associated to O( 2) mean-square error between the multilevel estimator and average with respect to the filtering distribution is shown to scale optimally, for example as O( 2) for optimal rates of convergence of the underlying diffusion approximation. The method is illustrated on some toy examples as well as estimation of interest rate based on real S&P 500 stock price data.

  12. Particle flow superpositional GLMB filter (United States)

    Saucan, Augustin-Alexandru; Li, Yunpeng; Coates, Mark


    In this paper we propose a Superpositional Marginalized δ-GLMB (SMδ-GLMB) filter for multi-target tracking and we provide bootstrap and particle flow particle filter implementations. Particle filter implementations of the marginalized δ-GLMB filter are computationally demanding. As a first contribution we show that for the specific case of superpositional observation models, a reduced complexity update step can be achieved by employing a superpositional change of variables. The resulting SMδ-GLMB filter can be readily implemented using the unscented Kalman filter or particle filtering methods. As a second contribution, we employ particle flow to produce a measurement-driven importance distribution that serves as a proposal in the SMδ-GLMB particle filter. In high-dimensional state systems or for highly- informative observations the generic particle filter often suffers from weight degeneracy or otherwise requires a prohibitively large number of particles. Particle flow avoids particle weight degeneracy by guiding particles to regions where the posterior is significant. Numerical simulations showcase the reduced complexity and improved performance of the bootstrap SMδ-GLMB filter with respect to the bootstrap Mδ-GLMB filter. The particle flow SMδ-GLMB filter further improves the accuracy of track estimates for highly informative measurements.

  13. Manipulation Robustness of Collaborative Filtering


    Benjamin Van Roy; Xiang Yan


    A collaborative filtering system recommends to users products that similar users like. Collaborative filtering systems influence purchase decisions and hence have become targets of manipulation by unscrupulous vendors. We demonstrate that nearest neighbors algorithms, which are widely used in commercial systems, are highly susceptible to manipulation and introduce new collaborative filtering algorithms that are relatively robust.

  14. Popping the filter bubble


    Hughes, Katie; Cronin, G; Welch, L


    So-called “fake news” is everywhere and is having a major impact on daily life from politics to education. The rapid growth of information and the numbers of people who can create it means that we need more sophisticated tools to process the news we receive. Join us to learn about different methods you can use to be your own fact checker and pop your filter bubble.

  15. Offsetting the Affective Filter

    Directory of Open Access Journals (Sweden)

    Barry Chametzky, PhD


    Full Text Available When forced to deal with a stressful, unfamiliar situation, how do people react? People are familiar, in a traditional setting, with sensory overload. But in an online environment, when learners are anxious, they exhibit different behaviors to help mediate their anxiety. Additionally, in an online environment, since visual clues are often lacking, how do these behaviors manifest themselves? People navigate stressful and/or unfamiliar situations by offsetting their affective filter.

  16. Filter Bank Fusion Frames


    Chebira, Amina; Fickus, Matthew; Mixon, Dustin G.


    In this paper we characterize and construct novel oversampled filter banks implementing fusion frames. A fusion frame is a sequence of orthogonal projection operators whose sum can be inverted in a numerically stable way. When properly designed, fusion frames can provide redundant encodings of signals which are optimally robust against certain types of noise and erasures. However, up to this point, few implementable constructions of such frames were known; we show how to construct them using ...

  17. Application of RPF in MEMS gyro random drift filtering (United States)

    Guowei, GAO; Yan, XIE


    With the development of micro-mechanical inertial technology, how to suppress the MEMS gyro’s random drift increasingly become a hot topic. In order to filter a certain type of MEMS gyro’s random drift, this paper introduces the regularized particle filter algorithm. The derivation of the algorithm and its application in MEMS gyro’s filtering process are described in detail in this paper: First, acquiring MEMS gyro’s static drift data and conducting data pre-treatment; then establishing the AR model by using time series analysis method, and transforming it into the corresponding state space model; finally, executing the estimation and compensation for MEMS gyro’s random drift with regular particle filter algorithm, and comparing it with other common methods in engineering. Tests and simulation results show that the regularized particle filter algorithm could achieve a good effect on the suppression of MEMS gyro’s random drift, it has a higher practical application value.

  18. Load compensation for single phase system using series active filter

    African Journals Online (AJOL)


    Load compensation for single phase system using series active filter. Kamala Kant Mishra. 1, Rajesh Gupta. 2. 1*Department of Electrical and Electronics Engineering, Kanpur Institute of Technology Kanpur, INDIA. 2 Department of Electrical Engineering, Motilal Nehru National Institute of Technology Allahabad, INDIA.

  19. Bypass surgery for complex middle cerebral artery aneurysms: an algorithmic approach to revascularization. (United States)

    Tayebi Meybodi, Ali; Huang, Wendy; Benet, Arnau; Kola, Olivia; Lawton, Michael T


    OBJECT Management of complex aneurysms of the middle cerebral artery (MCA) can be challenging. Lesions not amenable to endovascular techniques or direct clipping might require a bypass procedure with aneurysm obliteration. Various bypass techniques are available, but an algorithmic approach to classifying these lesions and determining the optimal bypass strategy has not been developed. The objective of this study was to propose a comprehensive and flexible algorithm based on MCA aneurysm location for selecting the best of multiple bypass options. METHODS Aneurysms of the MCA that required bypass as part of treatment were identified from a large prospectively maintained database of vascular neurosurgeries. According to its location relative to the bifurcation, each aneurysm was classified as a prebifurcation, bifurcation, or postbifurcation aneurysm. RESULTS Between 1998 and 2015, 30 patients were treated for 30 complex MCA aneurysms in 8 (27%) prebifurcation, 5 (17%) bifurcation, and 17 (56%) postbifurcation locations. Bypasses included 8 superficial temporal artery-MCA bypasses, 4 high-flow extracranial-to-intracranial (EC-IC) bypasses, 13 IC-IC bypasses (6 reanastomoses, 3 reimplantations, 3 interpositional grafts, and 1 in situ bypass), and 5 combination bypasses. The bypass strategy for prebifurcation aneurysms was determined by the involvement of lenticulostriate arteries, whereas the bypass strategy for bifurcation aneurysms was determined by rupture status. The location of the MCA aneurysm in the candelabra (Sylvian, insular, or opercular) determined the bypass strategy for postbifurcation aneurysms. No deaths that resulted from surgery were found, bypass patency was 90%, and the condition of 90% of the patients was improved or unchanged at the most recent follow-up. CONCLUSIONS The bypass strategy used for an MCA aneurysm depends on the aneurysm location, lenticulostriate anatomy, and rupture status. A uniform bypass strategy for all MCA aneurysms does not

  20. Iterative deblending using shaping regularization with a combined PNMO-MF-FK coherency filter (United States)

    Chen, Yangkang; Jin, Zhaoyu; Gan, Shuwei; Yang, Wencheng; Xiang, Kui; Bai, Min; Huang, Weilin


    Simultaneous shooting achieves a much faster acquisition but poses a challenging problem for subsequent processing because of the interference from the neighbor crews. Separation of different sources, also called deblending, becomes important for the overall success of the new acquisition technology. In this paper, we propose a novel deblending approach following the shaping regularization framework. The shaping operator is chosen as an effective filter, combining pseudo normal-moveout, median filtering, and frequency wavenumber filtering (PNMO-MF-FK). We combine the median-filter based deblending approaches and the FK filter based deblending approach within the proposed framework. Instead of simply using the median filter to remove blending noise, we apply a pseudo NMO (PNMO) to prepare a relatively flatter profile in advance, which can make the median filter more effective. It is the first time that the PNMO, median filtering, and FK filtering are combined to form a powerful coherency filter in order to improve the performance of iterative deblending. The proposed deblending approach with the PNMO-MF-FK filter can obtain successful performance within small number of iterations. Compared with the alternative MF-FK filter and FK filter, the PNMO-MF-FK filter can obtain obviously better deblending results. We use both simulated synthetic and field data examples to demonstrate the performance of the proposed approach.

  1. Experimental comparison of point-of-use filters for drinking water ultrafiltration. (United States)

    Totaro, M; Valentini, P; Casini, B; Miccoli, M; Costa, A L; Baggiani, A


    Waterborne pathogens such as Pseudomonas spp. and Legionella spp. may persist in hospital water networks despite chemical disinfection. Point-of-use filtration represents a physical control measure that can be applied in high-risk areas to contain the exposure to such pathogens. New technologies have enabled an extension of filters' lifetimes and have made available faucet hollow-fibre filters for water ultrafiltration. To compare point-of-use filters applied to cold water within their period of validity. Faucet hollow-fibre filters (filter A), shower hollow-fibre filters (filter B) and faucet membrane filters (filter C) were contaminated in two different sets of tests with standard bacterial strains (Pseudomonas aeruginosa DSM 939 and Brevundimonas diminuta ATCC 19146) and installed at points-of-use. Every day, from each faucet, 100 L of water was flushed. Before and after flushing, 250 mL of water was collected and analysed for microbiology. There was a high capacity of microbial retention from filter C; filter B released only low Brevundimonas spp. counts; filter A showed poor retention of both micro-organisms. Hollow-fibre filters did not show good micro-organism retention. All point-of-use filters require an appropriate maintenance of structural parameters to ensure their efficiency. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  2. Annular MHD Physics for Turbojet Energy Bypass (United States)

    Schneider, Steven J.


    The use of annular Hall type MHD generator/accelerator ducts for turbojet energy bypass is evaluated assuming weakly ionized flows obtained from pulsed nanosecond discharges. The equations for a 1-D, axisymmetric MHD generator/accelerator are derived and numerically integrated to determine the generator/accelerator performance characteristics. The concept offers a shockless means of interacting with high speed inlet flows and potentially offers variable inlet geometry performance without the complexity of moving parts simply by varying the generator loading parameter. The cycle analysis conducted iteratively with a spike inlet and turbojet flying at M = 7 at 30 km altitude is estimated to have a positive thrust per unit mass flow of 185 N-s/kg. The turbojet allowable combustor temperature is set at an aggressive 2200 deg K. The annular MHD Hall generator/accelerator is L = 3 m in length with a B(sub r) = 5 Tesla magnetic field and a conductivity of sigma = 5 mho/m for the generator and sigma= 1.0 mho/m for the accelerator. The calculated isentropic efficiency for the generator is eta(sub sg) = 84 percent at an enthalpy extraction ratio, eta(sub Ng) = 0.63. The calculated isentropic efficiency for the accelerator is eta(sub sa) = 81 percent at an enthalpy addition ratio, eta(sub Na) = 0.62. An assessment of the ionization fraction necessary to achieve a conductivity of sigma = 1.0 mho/m is n(sub e)/n = 1.90 X 10(exp -6), and for sigma = 5.0 mho/m is n(sub e)/n = 9.52 X 10(exp -6).

  3. Tricarboxylic Acid Cycle and Glyoxylate Bypass. (United States)

    Cronan, John E; Laporte, David


    The tricarboxylic acid (TCA) cycle plays two essential roles in metabolism. First, under aerobic conditions the cycle is responsible for the total oxidation of acetyl-CoA that is derived mainly from the pyruvate produced by glycolysis. Second, TCA cycle intermediates are required in the biosynthesis of several amino acids. Although the TCA cycle has long been considered a "housekeeping" pathway in Escherichia coli and Salmonella enterica, the pathway is highly regulated at the transcriptional level. Much of this control is exerted in response to respiratory conditions. The TCA cycle gene-protein relationship and mutant phenotypes have been well studied, although a few loose ends remain. The realization that a "shadow" TCA cycle exists that proceeds through methylcitrate has cleared up prior ambiguities. The glyoxylate bypass has long been known to be essential for growth on carbon sources such as acetate or fatty acids because this pathway allowsnet conversion of acetyl-CoA to metabolic intermediates. Strains lacking this pathway fail to grow on these carbon sources, since acetate carbon entering the TCA cycle is quantitatively lost as CO2 resulting in the lack of a means to replenish the dicarboxylic acids consumed in amino acid biosynthesis. The TCA cycle gene-protein relationship and mutant phenotypes have been well studied, although the identity of the small molecule ligand that modulates transcriptional control of the glyoxylate cycle genes by binding to the IclR repressor remains unknown. The activity of the cycle is also exerted at the enzyme level by the reversible phosphorylation of the TCA cycle enzyme isocitrate dehydrogenase catalyzed by a specific kinase/phosphatase to allow isocitratelyase to compete for isocitrate and cleave this intermediate to glyoxylate and succinate.

  4. Comparison of filter with Prairie and European Network data

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.


    Earlier notes derived a model for the hydrodynamics, ablation, and radiation of meteor impacts at the level needed to infer meteor parameters from observations and extended it to objects that fragment during entry, using models based on related cometary studies. This note completes the comparison of the resulting filter model to European and Prairie Network (EN and PN) data and models of meteor impact. In cases of mutual applicability, US and European models give broadly consistent results. The quantitative analysis of the EN and PN data is best discussed in conjunction with the Russian program of its analysis, because the Russian program has bypassed the large reported photometrically based masses to derive more plausible estimates of sizes, masses, and radiation efficiencies, which are the primary quantities of concern here. This note completes the discussion of the PN and EN data begun earlier, uses the data to produce filter predictions, and compares it with observations and the predictions of the Russian analytic effort. The overall agreement is useful in that the Russian efforts have employed more complex models that use observational data directly, while the filter model is at a level of simplification much better suited to data inversion.


    Energy Technology Data Exchange (ETDEWEB)

    John P. Hurley; Ann K. Henderson; Jan W. Nowok; Michael L. Swanson


    In order to reach the highest possible efficiencies in a coal-fired turbine-based power system, the turbine should be directly fired with the products of coal conversion. Two main types of systems employ these turbines: those based on pressurized fluidized-bed combustors and those based on integrated gasification combined cycles. In both systems, suspended particulates must be cleaned from the gas stream before it enters the turbine so as to prevent fouling and erosion of the turbine blades. To produce the cleanest gas, barrier filters are being developed and are in use in several facilities. Barrier filters are composed of porous, high-temperature materials that allow the hot gas to pass but collect the particulates on the surface. The three main configurations of the barrier filters are candle, cross-flow, and tube filters. Both candle and tube filters have been tested extensively. They are composed of coarsely porous ceramic that serves as a structural support, overlain with a thin, microporous ceramic layer on the dirty gas side that serves as the primary filter surface. They are highly efficient at removing particulate matter from the gas stream and, because of their ceramic construction, are resistant to gas and ash corrosion. However, ceramics are brittle and individual elements can fail, allowing particulates to pass through the hole left by the filter element and erode the turbine. Preventing all failure of individual ceramic filter elements is not possible at the present state of development of the technology. Therefore, safeguard devices (SGDs) must be employed to prevent the particulates streaming through occasional broken filters from reaching the turbine. However, the SGD must allow for the free passage of gas when it is not activated. Upon breaking of a filter, the SGD must either mechanically close or quickly plug with filter dust to prevent additional dust from reaching the turbine. Production of a dependable rapidly closing autonomous mechanical

  6. Ceramic water filters impregnated with silver nanoparticles as a point-of-use water-treatment intervention for HIV-positive individuals in Limpopo Province, South Africa: a pilot study of technological performance and human health benefits. (United States)

    Abebe, Lydia Shawel; Smith, James A; Narkiewicz, Sophia; Oyanedel-Craver, Vinka; Conaway, Mark; Singo, Alukhethi; Amidou, Samie; Mojapelo, Paul; Brant, Julia; Dillingham, Rebecca


    Waterborne pathogens present a significant threat to people living with the human immunodeficiency virus (PLWH). This study presents a randomized, controlled trial that evaluates whether a household-level ceramic water filter (CWF) intervention can improve drinking water quality and decrease days of diarrhea in PLWH in rural South Africa. Seventy-four participants were randomized in an intervention group with CWFs and a control group without filters. Participants in the CWF arm received CWFs impregnated with silver nanoparticles and associated safe-storage containers. Water and stool samples were collected at baseline and 12 months. Diarrhea incidence was self-reported weekly for 12 months. The average diarrhea rate in the control group was 0.064 days/week compared to 0.015 days/week in the intervention group (p water and decrease days of diarrhea for PLWH in rural South Africa.

  7. An Experimental Design of Bypass Magneto-Rheological (MR) damper (United States)

    Rashid, MM; Aziz, Mohammad Abdul; Raisuddin Khan, Md.


    The magnetorheological (MR) fluid bypass damper fluid flow through a bypass by utilizing an external channel which allows the controllability of MR fluid in the channel. The Bypass MR damper (BMRD) contains a rectangular bypass flow channel, current controlled movable piston shaft arrangement and MR fluid. The static piston coil case is winding by a coil which is used inside the piston head arrangement. The current controlled coil case provides a magnetic flux through the BMRD cylinder for controllability. The high strength of alloy steel materials are used for making piston shaft which allows magnetic flux propagation throughout the BMRD cylinder. Using the above design materials, a Bypass MR damper is designed and tested. An excitation of current is applied during the experiment which characterizes the BMRD controllability. It is shown that the BMRD with external flow channel allows a high controllable damping force using an excitation current. The experimental result of damping force-displacement characteristics with current excitation and without current excitation are compared in this research. The BMRD model is validated by the experimental result at various frequencies and applied excitation current.

  8. Natural Product Screening Reveals Naphthoquinone Complex I Bypass Factors.

    Directory of Open Access Journals (Sweden)

    Scott B Vafai

    Full Text Available Deficiency of mitochondrial complex I is encountered in both rare and common diseases, but we have limited therapeutic options to treat this lesion to the oxidative phosphorylation system (OXPHOS. Idebenone and menadione are redox-active molecules capable of rescuing OXPHOS activity by engaging complex I-independent pathways of entry, often referred to as "complex I bypass." In the present study, we created a cellular model of complex I deficiency by using CRISPR genome editing to knock out Ndufa9 in mouse myoblasts, and utilized this cell line to develop a high-throughput screening platform for novel complex I bypass factors. We screened a library of ~40,000 natural product extracts and performed bioassay-guided fractionation on a subset of the top scoring hits. We isolated four plant-derived 1,4-naphthoquinone complex I bypass factors with structural similarity to menadione: chimaphilin and 3-chloro-chimaphilin from Chimaphila umbellata and dehydro-α-lapachone and dehydroiso-α-lapachone from Stereospermum euphoroides. We also tested a small number of structurally related naphthoquinones from commercial sources and identified two additional compounds with complex I bypass activity: 2-methoxy-1,4-naphthoquinone and 2-methoxy-3-methyl-1,4,-naphthoquinone. The six novel complex I bypass factors reported here expand this class of molecules and will be useful as tool compounds for investigating complex I disease biology.

  9. Thermal activation of dislocations in large scale obstacle bypass (United States)

    Sobie, Cameron; Capolungo, Laurent; McDowell, David L.; Martinez, Enrique


    Dislocation dynamics simulations have been used extensively to predict hardening caused by dislocation-obstacle interactions, including irradiation defect hardening in the athermal case. Incorporating the role of thermal energy on these interactions is possible with a framework provided by harmonic transition state theory (HTST) enabling direct access to thermally activated reaction rates using the Arrhenius equation, including rates of dislocation-obstacle bypass processes. Moving beyond unit dislocation-defect reactions to a representative environment containing a large number of defects requires coarse-graining the activation energy barriers of a population of obstacles into an effective energy barrier that accurately represents the large scale collective process. The work presented here investigates the relationship between unit dislocation-defect bypass processes and the distribution of activation energy barriers calculated for ensemble bypass processes. A significant difference between these cases is observed, which is attributed to the inherent cooperative nature of dislocation bypass processes. In addition to the dislocation-defect interaction, the morphology of the dislocation segments pinned to the defects play an important role on the activation energies for bypass. A phenomenological model for activation energy stress dependence is shown to describe well the effect of a distribution of activation energies, and a probabilistic activation energy model incorporating the stress distribution in a material is presented.

  10. Photovoltaic-module bypass-diode encapsulation. Annual report

    Energy Technology Data Exchange (ETDEWEB)


    The design and processing techniques necessary to incorporate bypass diodes within the module encapsulant are presented in this annual report. A comprehensive survey of available pad-mounted PN junction and Schottky diodes led to the selection of Semicon PN junction diode cells for this application. Diode junction-to-heat spreader thermal resistance measurements, performed on a variety of mounted diode chip types and sizes, have yielded values which are consistently below 1/sup 0/C per watt, but show some instability when thermally cycled over the temperature range from -40 to 150/sup 0/C. Based on the results of a detailed thermal analysis, which covered the range of bypass currents from 2 to 20 amperes, three representative experimental modules, each incorporating integral bypass diode/heat spreader assemblies of various sizes, were designed and fabricated. Thermal testing of these modules has enabled the formation of a recommended heat spreader plate sizing relationship. The production cost of three encapsulated bypass diode/heat spreader assemblies were compared with similarly rated externally-mounted packaged diodes. An assessment of bypass diode reliability, which relies heavily on rectifying diode failure rate data, leads to the general conclusion that, when proper designed and installed, these devices will improve the overall reliability of a terrestrial array over a 20 year design lifetime.

  11. Atrial Fibrillation, Neurocognitive Decline and Gene Expression After Cardiopulmonary Bypass. (United States)

    Dalal, Rahul S; Sabe, Ashraf A; Elmadhun, Nassrene Y; Ramlawi, Basel; Sellke, Frank W


    Atrial fibrillation and neurocognitive decline are common complications after cardiopulmonary bypass. By utilizing genomic microarrays we investigate whether gene expression is associated with postoperative atrial fibrillation and neurocognitive decline. Twenty one cardiac surgery patients were prospectively matched and underwent neurocognitive assessments pre-operatively and four days postoperatively. The whole blood collected in the pre-cardiopulmonary bypass, 6 hours after-cardiopulmonary bypass, and on the 4th postoperative day was hybridized to Affymetrix Gene Chip U133 Plus 2.0 Microarrays. Gene expression in patients who developed postoperative atrial fibrillation and neurocognitive decline (n=6; POAF+NCD) was compared with gene expression in patients with postoperative atrial fibrillation and normal cognitive function (n=5; POAF+NORM) and patients with sinus rhythm and normal cognitive function (n=10; SR+NORM). Regulated genes were identified using JMP Genomics 4.0 with a false discovery rate of 0.05 and fold change of >1.5 or cardiopulmonary bypass, and 34 named genes four days postoperatively (Pcardiopulmonary bypass may have differential genomic responses compared to normal patients and patients with only postoperative atrial fibrillation, suggesting common pathophysiology for these conditions. Further exploration of these genes may provide insight into the etiology and improvements of these morbid outcomes.

  12. An Improved Sequential Smoothing Particle Filtering Method

    Directory of Open Access Journals (Sweden)

    Cao Shijie


    Full Text Available In order to cope with the challenges of non-cooperative targets such as stealth targets to modern radar, especially when traditional threshold detection and tracking methods can hardly detect fast-moving stealth targets, technological innovation has long been required. In this paper we have proposed a new algorithm which can reduce computational cost and improve tracking accuracy. Firstly, the number of particles in the traditional particle filter is reduced and a small number of sampling points are derived from the possible distribution of the target to be tracked, each given a proper weight. Then, the transformed sampling points are sequentially smoothed. And finally, the target positions are estimated. The simulation results show that the proposed algorithm is more accurate than the traditional particle filter algorithm and has lower computational complexity. In the case when SNR is between 0dB to 15dB, a total of 100 Monte Carlo simulations are carried out, obtaining a high detection probability. The detection probability of the improved algorithm is higher than that of the existing particle filter at 7dB. Also, the computational cost is lower than the existing particle filter algorithm.


    Energy Technology Data Exchange (ETDEWEB)

    M.A. Alvin


    Through sponsorship from the Department of Energy's National Energy Technology Laboratory (DOE/NETL), development and manufacture of advanced second generation candle filters was undertaken in the early 1990's. Efforts were primarily focused on the manufacture of fracture toughened, 1.5 m, continuous fiber ceramic composite (CFCC) and filament wound candle filters by 3M, McDermott, DuPont Lanxide Composites, and Techniweave. In order to demonstrate long-term thermal, chemical, and mechanical stability of the advanced second generation candle filter materials, Siemens Westinghouse initiated high temperature, bench-scale, corrosion testing of 3M's CVI-SiC and DuPont's PRD-66 mini-candles, and DuPont's CFCC SiC-SiC and IF&P Fibrosic{sup TM} coupons under simulated, pressurized fluidized-bed combustion (PFBC) conditions. This effort was followed by an evaluation of the mechanical and filtration performance of the advanced second generation filter elements in Siemens Westinghouse's bench-scale PFBC test facility in Pittsburgh, Pennsylvania. Arrays of 1.4-1.5 m 3M CVI-SiC, DuPont PRD-66, DuPont SiC-SiC, and IF&P Fibrosic{sup TM} candles were subjected to steady state process operating conditions, increased severity thermal transients, and accelerated pulse cycling test campaigns which represented {approx}1760 hours of equivalent filter operating life. Siemens Westinghouse subsequently participated in early material surveillance programs which marked entry of the 3M CVI-SiC and DuPont PRD-66 candle filters in Siemens Westinghouse Advanced Particulate Filtration (APF) system at the American Electric Power (AEP) Tidd Demonstration Plant in Brilliant, Ohio. Siemens Westinghouse then conducted an extended, accelerated life, qualification program, evaluating the performance of the 3M, McDermott, and Techniweave oxide-based CFCC filter elements, modified DuPont PRD-66 elements, and the Blasch, Scapa Cerafil{sup TM}, and Specific Surface monolithic

  14. Wiener filter for filtered back projection in digital breast tomosynthesis (United States)

    Wang, Xinying; Mainprize, James G.; Wu, Gang; Yaffe, Martin J.


    Conventional filtered back projection (FBP) reconstruction for digital breast tomosynthesis (DBT) can suffer from a low signal to noise ratio. Because of the strong amplification by the reconstruction filters (ramp, apodization and slice thickness), noise at high spatial frequencies can be greatly increased. Image enhancement by Wiener filtering is investigated as a possible method to improve image quality. A neighborhood wavelet coefficient window technique is used to estimate the noise content of projection images and a Wiener filter is applied to the projection images. The neighborhood wavelet coefficient window is a non-linear technique, which may cause the Wiener filters estimated before and after the application of the reconstruction filters to be different. Image quality of a FBP reconstruction with and without Wiener filtering is investigated using a Fourier-based observer detectability metric ( d' ) for evaluation. Simulations of tomosynthesis are performed in both homogeneous and anatomic textured backgrounds containing lowcontrast masses or small microcalcifications. Initial results suggest that improvements in detectability can be achieved when the Wiener filter is applied, especially when the Wiener filter is estimated for the reconstruction filtered projections.

  15. Are laparoscopic gastric bypass after gastroplasty and primary laparoscopic gastric bypass similar in terms of results? (United States)

    Cadière, Guy-Bernard; Himpens, Jacques; Bazi, Michel; Cadière, Benjamin; Vouche, Michael; Capelluto, Elie; Dapri, Giovanni


    This retrospective study compares the results of primary gastric bypass (PGB) versus secondary gastric bypass (SGB) performed after gastroplasty. Between January 2004 and August 2008, 576 consecutive patients benefited from laparoscopic gastric bypass (LGB) in our hospital. Four hundred seventy patients (81.6%) were available for full evaluation. Primary outcome measures were operative time, conversion to open surgery and mortality, hospital stay, early and late complications, reoperations, efficacy, and patient satisfaction. Three hundred sixty-two patients benefited from a PGB and 108 from SGB. Median preoperative BMI was 42 kg/m2 (34.8-63.5; PGB) and 39 kg/m2 (20.9-64.5; SGB; p = 0.002). Median operative time was 109 min (40-436; PGB) and 194 min (80-430; SGB; p < 0.001). There was no conversion to open surgery or mortality in either group. Median hospital stay was 4 days (3-95; PGB) and 5 days (2-114; SGB; p < 0.001). Early complications were recorded in 37 patients (10.2%) after PGB and in 24 patients (22.2%) after SGB (p < 0.001). Reoperation was necessary in 12 patients (3.3%) after PGB and in 9 patients (8.3%) after SGB (p = 0.03). Median follow-up was 35 months (12-66; PGB), and 34 months (12-66; SGB; NS). Late complications were achieved in 46 patients (12.7%) after PGB and in 33 patients (30.6%) after SGB (p < 0.001). Reoperation was necessary in 17 patients (4.7%) after PGB and in 11 patients (10.2%) after SGB (p = 0.03). Mean % EWL was 74.2% after PGB and 69.9% after SGB (NS). After PGB, 89% of the patients was satisfied, 4% neutral, and 6% unsatisfied; after SGB, 79% was satisfied, 10% neutral, and 11% unsatisfied (p = 001). Weight loss after PGB and SGB is not statistically significantly different. Otherwise, operative time, hospital stay, complications, and revision rate are statistically significantly higher after SGB (p < 0.001).

  16. Superconducting notch filter

    Energy Technology Data Exchange (ETDEWEB)

    Pang, C S; Falco, C M; Kampwirth, R T; Schuller, I K; Hudak, J J; Anastasio, T A


    Results of a preliminary investigation of a superconducting notch filter for possible application in the 2 to 30 MHz high frequency (HF) communication band are presented. The circuit was successfully implemented using planar geometry so that closed cycle refrigeration could be used to cool circuits fabricated from high T/sub c/ Nb/sub 3/Sn or Nb/sub 3/Ge thin films. In the present design, circuit Q's of about 2 x 10/sup 3/ were obtained with 50-ohm source and output impedance. (TFD)

  17. Spindoktorer et politisk filter


    Talic, Elvedin; Bernt, Rune; Mortensen, Mass Holmegård


    Through the TV and other media, many rumors about what a spin-doctor does and the nature of his services have spread. We would like to clarify the function; role and influence the spin-doctor have on Danish politics. We will look specifically at the relationship of power between the Ministers and spin-doctors, and the spin-doctors and media, as some believe that the spin-doctor sometimes will rise to power. We will also take look at the filter function between spin-doctors and media, as it is...

  18. Advances in Collaborative Filtering (United States)

    Koren, Yehuda; Bell, Robert

    The collaborative filtering (CF) approach to recommenders has recently enjoyed much interest and progress. The fact that it played a central role within the recently completed Netflix competition has contributed to its popularity. This chapter surveys the recent progress in the field. Matrix factorization techniques, which became a first choice for implementing CF, are described together with recent innovations. We also describe several extensions that bring competitive accuracy into neighborhood methods, which used to dominate the field. The chapter demonstrates how to utilize temporal models and implicit feedback to extend models accuracy. In passing, we include detailed descriptions of some the central methods developed for tackling the challenge of the Netflix Prize competition.

  19. Multilevel ensemble Kalman filtering

    KAUST Repository

    Hoel, Hakon


    This work embeds a multilevel Monte Carlo sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF) in the setting of finite dimensional signal evolution and noisy discrete-time observations. The signal dynamics is assumed to be governed by a stochastic differential equation (SDE), and a hierarchy of time grids is introduced for multilevel numerical integration of that SDE. The resulting multilevel EnKF is proved to asymptotically outperform EnKF in terms of computational cost versus approximation accuracy. The theoretical results are illustrated numerically.

  20. Charcoal filter testing

    Energy Technology Data Exchange (ETDEWEB)

    Lyons, J. [Nuclear Regulatory Commission, Washington, DC (United States)


    In this very brief, informal presentation, a representative of the US Nuclear Regulatory Commission outlines some problems with charcoal filter testing procedures and actions being taken to correct the problems. Two primary concerns are addressed: (1) the process to find the test method is confusing, and (2) the requirements of the reference test procedures result in condensation on the charcoal and causes the test to fail. To address these problems, emergency technical specifications were processed for three nuclear plants. A generic or an administrative letter is proposed as a more permanent solution. 1 fig.

  1. The optimum sunglass filter? (United States)

    Soederberg, Per G.; Michael, Ralph; Ayala, Marcelo; Wu, Jiangmei; Loefgren, Stefan; Merriam, John; Chen, Enping


    It is concluded that sunglasses shall block UVR and toxic blue light, allow transmittance of signal light and bring luminous intensity behind the filters to a comfortable level. It was found that some commercially available sunglasses, apart from one pair of photochromatic dark state lenses tested, block ultraviolet radiation (UVR) adequately. Further, it was found that it is possible to block the toxic blue radiation without interfering substantially on blue signal light perception. However, none of the sunglasses tested blocked the toxic blue light enough.

  2. Digital Filters for Low Frequency Equalization

    DEFF Research Database (Denmark)

    Tyril, Marni; Abildgaard, J.; Rubak, Per


    Digital filters with high resolution in the low-frequency range are studied. Specifically, for a given computational power, traditional IIR filters are compared with warped FIR filters, warped IIR filters, and modified warped FIR filters termed warped individual z FIR filters (WizFIR). The results...

  3. Rankine cycle load limiting through use of a recuperator bypass (United States)

    Ernst, Timothy C.


    A system for converting heat from an engine into work includes a boiler coupled to a heat source for transferring heat to a working fluid, a turbine that transforms the heat into work, a condenser that transforms the working fluid into liquid, a recuperator with one flow path that routes working fluid from the turbine to the condenser, and another flow path that routes liquid working fluid from the condenser to the boiler, the recuperator being configured to transfer heat to the liquid working fluid, and a bypass valve in parallel with the second flow path. The bypass valve is movable between a closed position, permitting flow through the second flow path and an opened position, under high engine load conditions, bypassing the second flow path.

  4. Severe hypoglycaemia post-gastric bypass requiring partial pancreatectomy

    DEFF Research Database (Denmark)

    Patti, M E; McMahon, G; Mun, E C


    AIMS/HYPOTHESIS: Postprandial hypoglycaemia following gastric bypass for obesity is considered a late manifestation of the dumping syndrome and can usually be managed with dietary modification. We investigated three patients with severe postprandial hypoglycaemia and hyperinsulinaemia unresponsive...... was assessed in all three patients. RESULTS: All three patients had evidence of severe postprandial hyperinsulinaemia and hypoglycaemia. In one patient, reversal of gastric bypass was ineffective in reversing hypoglycaemia. All three patients ultimately required partial pancreatectomy for control...... of neuroglycopenia; pancreas pathology of all patients revealed diffuse islet hyperplasia and expansion of beta cell mass. CONCLUSIONS/INTERPRETATION: These findings suggest that gastric bypass-induced weight loss may unmask an underlying beta cell defect or contribute to pathological islet hyperplasia, perhaps via...

  5. Miller-Fisher syndrome after coronary artery bypass surgery. (United States)

    Aldag, Mustafa; Albeyoglu, Sebnem; Ciloglu, Ufuk; Kutlu, Hakan; Ceylan, Levent


    Miller-Fisher syndrome (MFS) is an uncommon neurological disorder that is considered a variant of the Guillain-Barre syndrome (GBS). It is clinically defined by a triad of symptoms, namely ataxia, areflexia and ophthalmoplegia. These acute inflammatory polyradiculopathic syndromes can be triggered by viral infections, major surgery, pregnancy or vaccination. While the overall incidence of GBS is 1.2-2.3 per 100 000 per year, MFS is a relatively rare disorder. Only six cases of GBS after cardiac surgery have been reported, and to our knowledge, we describe the first case of MFS after coronary artery bypass surgery. Although cardiac surgery with cardiopulmonary bypass may increase the incidence of MFS and GBS, the pathological mechanism is unclear. Cardiac surgery may be a trigger for the immune-mediated response and may cause devastating complications. It is also important to be alert to de novo autoimmune and unexpected neurological disorders such as MFS after coronary bypass surgery.

  6. Neuroprotective Strategies during Cardiac Surgery with Cardiopulmonary Bypass (United States)

    Salameh, Aida; Dhein, Stefan; Dähnert, Ingo; Klein, Norbert


    Aortocoronary bypass or valve surgery usually require cardiac arrest using cardioplegic solutions. Although, in principle, in a number of cases beating heart surgery (so-called off-pump technique) is possible, aortic or valve surgery or correction of congenital heart diseases mostly require cardiopulmonary arrest. During this condition, the heart-lung machine also named cardiopulmonary bypass (CPB) has to take over the circulation. It is noteworthy that the invention of a machine bypassing the heart and lungs enabled complex cardiac operations, but possible negative effects of the CPB on other organs, especially the brain, cannot be neglected. Thus, neuroprotection during CPB is still a matter of great interest. In this review, we will describe the impact of CPB on the brain and focus on pharmacological and non-pharmacological strategies to protect the brain. PMID:27879647

  7. Robotically assisted totally endoscopic coronary artery bypass surgery (United States)

    Canale, Leonardo Secchin; Mick, Stephanie; Mihaljevic, Tomislav; Nair, Ravi


    Robotically assisted totally endoscopic coronary artery bypass surgery has emerged as a feasible and efficient alternative to conventional full sternotomy coronary artery bypass graft surgery in selected patients. This minimally invasive approach using the daVinci robotic system allows fine intrathoracic maneuvers and excellent view of the coronary arteries. Both on-pump and off-pump operations can be performed to treat single and multivessel disease. Hybrid approaches have the potential of offering complete revascularization with the “best of both worlds” from surgery (internal mammary artery anastomosis in less invasive fashion) and percutaneous coronary intervention (least invasive approach). In this article we review the indications, techniques, short and long term results, as well as current developments in totally endoscopic robotic coronary artery bypass operations. PMID:24251021

  8. Surgical resident training using real-time simulation of cardiopulmonary bypass physiology with echocardiography. (United States)

    Martin, Jeremiah T; Reda, Hassan; Dority, Jeremy S; Zwischenberger, Joseph B; Hassan, Zaki-Udin


    With increasing complexity of medical care and continuing limitations on medical education, the use of simulation is becoming ever more important. Several simulators have been developed to teach procedural-based surgical tasks. The care of the cardiac surgical patient requires an in-depth understanding of physiology, particularly as pertains to cardiopulmonary bypass. We describe the use of the Human Patient Simulator (HPS) to teach perioperative fundamentals to surgical residents. General surgery residents from the University of Kentucky participated in an interactive simulation pilot program. The METI (Medical Education Technology, Inc, Sarasota, Florida) HPS was used with custom programming to demonstrate simulated intraoperative and postoperative physiology related to cardiopulmonary bypass. Didactics, in addition to intraoperative echocardiographic images, were provided. Fund of knowledge was assessed by a computerized pre- and posttest that was administered to the trainees, and self-assessment data were collected using a Likert scale. Nineteen general surgery residents participated. An overall improvement in performance on the test was demonstrated from 63% correct to 85% correct. In general, residents found the simulation useful, appreciated the opportunity to treat crisis situations without risk of harm to a patient, and felt they could apply the knowledge gained from this program in their future practice. Simulation serves as a useful adjunct to medical education. We have demonstrated the use of the HPS to provide a real-time simulation of the physiology of cardiopulmonary bypass and postoperative care. We plan to use this system as part of our standard curriculum of training rotating residents and junior fellows and anticipate this system could be used as part of future cardiothoracic simulations. Copyright © 2011 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  9. Right ventricle contractility during early postoperative period after coronary artery bypass grafting with cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    А. Е. Баутин


    Full Text Available Emphasis in this research was placed on contractility of the right ventricle with regard to its relationship with systemic hemodynamics in patients undergoing coronary artery bypass grafting (CABG under cardiopulmonary bypass (CPB. The study included 25 patients (14 males, 11 females, mean age was 587 years admitted to ICU after CABG under CPB. All patients required inotropic therapy. The criterion for prescribing inotropic support in the postoperative period was a drop of the stroke volume index of the left ventricle below 35 ml/m 2 provided that the values of this indicator were normal before the perfusion period. Patients with previous pathology of the right ventricle or right coronary artery were excluded from the study. To evaluate the right ventricular function and systemic hemodynamics indicators, use was made of the PiCCO plus system and VoLEF addon device. It was found out that reduced contractility of the right ventricle may cause the reduction in stroke volume of the left ventricle with normal contractility. It was also observed that the increase of preload in patients with right ventricular ejection fraction less than 30% does not improve its function but leads to the increase of its end-diastolic volume. In 68% of cases, the need in inotropic agents in the early postoperative period after CABG was associated with the drop in right ventricle contractility, in 40% - with isolated right ven-tricular dysfunction. Patients with isolated reduction in right ventricle contractility required a longer period of inotropic support and ICU stay as compared with those with left ventricular failure.

  10. Diabetes resolution after one anastomosis gastric bypass. (United States)

    Abu-Abeid, Adam; Lessing, Yonatan; Pencovich, Niv; Dayan, Danit; Klausner, Joseph M; Abu-Abeid, Subhi


    Diabetes and other obesity-related diseases are a worldwide pandemic that transcends geographic borders as well as socioeconomic levels. Currently, it is well known that medical treatment alone is insufficient to ensure adequate and sustainable weight loss and co-morbidity resolution. It has been well proven that bariatric surgery can produce almost immediate resolution of diabetes and other co-morbidities as well as long-term weight loss. Here, we present our experience with the one anastomosis gastric bypass (OAGB) in terms of weight loss and diabetes resolution with 1 year of follow-up. Large, metropolitan, tertiary, university hospital. A retrospective analysis of all patients who underwent OAGB between March 2015 and March 2016 was performed. Patient demographic characteristics, co-morbidities, operative and postoperative data, as well as first year outcomes were collected and analyzed. There were 407 patients who underwent OAGB (254 females, average age 41.8 ± 12.05 yr, body mass index = 41.7 ± 5.77 kg/m 2 ). Of patients, 102 (25.1%) had diabetes with average glycosylated hemoglobin of 8.64 ± 1.94 g%, 93 (22.8%) had hypertension, 123 (28.8%) had hyperlipidemia, and 35 patients (8.6%) had obstructive sleep apnea. The average length of hospital stay was 2.2 ± .84 days (range, 2-10 d). The average excess weight loss 1 year after surgery was 88.9 ± 27.3. After 1 year, follow-up data were available for more than 85% of the study's general population. Of 102 diabetic patients, only 8 (7.8%) were still considered diabetic and taking antidiabetic medication, with an average glycosylated hemoglobin of 5.4 ± 0.6. OAGB may be performed safely and with promising efficacy as both a primary and a revisional bariatric surgery, and it offers excellent resolution of diabetes. Copyright © 2018 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  11. Acetaminophen attenuates lipid peroxidation in children undergoing cardiopulmonary bypass. (United States)

    Simpson, Scott A; Zaccagni, Hayden; Bichell, David P; Christian, Karla G; Mettler, Bret A; Donahue, Brian S; Roberts, L Jackson; Pretorius, Mias


    Hemolysis, occurring during cardiopulmonary bypass, is associated with lipid peroxidation and postoperative acute kidney injury. Acetaminophen inhibits lipid peroxidation catalyzed by hemeproteins and in an animal model attenuated rhabdomyolysis-induced acute kidney injury. This pilot study tests the hypothesis that acetaminophen attenuates lipid peroxidation in children undergoing cardiopulmonary bypass. Single-center prospective randomized double-blinded study. University-affiliated pediatric hospital. Thirty children undergoing elective surgical correction of a congenital heart defect. Patients were randomized to acetaminophen (OFIRMEV [acetaminophen] injection; Cadence Pharmaceuticals, San Diego, CA) or placebo every 6 hours for four doses starting before the onset of cardiopulmonary bypass. Markers of hemolysis, lipid peroxidation (isofurans and F2-isoprostanes), and acute kidney injury were measured throughout the perioperative period. Cardiopulmonary bypass was associated with a significant increase in free hemoglobin (from a prebypass level of 9.8 ± 6.2 mg/dL to a peak of 201.5 ± 42.6 mg/dL postbypass). Plasma and urine isofuran and F2-isoprostane concentrations increased significantly during surgery. The magnitude of increase in plasma isofurans was greater than the magnitude in increase in plasma F2-isoprostanes. Acetaminophen attenuated the increase in plasma isofurans compared with placebo (p = 0.02 for effect of study drug). There was no significant effect of acetaminophen on plasma F2-isoprostanes or urinary makers of lipid peroxidation. Acetaminophen did not affect postoperative creatinine, urinary neutrophil gelatinase-associated lipocalin, or prevalence of acute kidney injury. Cardiopulmonary bypass in children is associated with hemolysis and lipid peroxidation. Acetaminophen attenuated the increase in plasma isofuran concentrations. Future studies are needed to establish whether other therapies that attenuate or prevent the effects of free

  12. From Microwave Filter to Digital Filter and Back Again

    DEFF Research Database (Denmark)

    Dalby, Arne Brejning


    A new very simple state variable flow graph representation for interdigital transmission line bandpass filters is presented, which has led to two important results: 1) A new type of digital filter with properties, that surpass the properties of most other (all pole) digital filtertypes. 2......) The study of the new digital filtertype has led to design formulas for interdigital transmission line filters that are very simple compared to the hitherto known formulas. The accuracy is the same or better....

  13. A Bypass Program of Supportive Instruction for Secondary Students with Learning Disabilities. (United States)

    Mosby, Robert J.


    The developmental bypass teaching technique (which provides students an opportunity to bypass their learning deficits) was studied with regard to social studies achievement and classroom behaviors in 50 learning disabled junior high school students. (Author/PHR)

  14. Reduced complement activation during cardiopulmonary bypass does not affect the postoperative acute phase response

    NARCIS (Netherlands)

    van den Goor, J.; Nieuwland, R.; van den Brink, A.; van Oeveren, W.; Rutten, P.; Tijssen, J.; Eijsman, L.


    Objective: In the present study the relationship was evaluated between perioperative inflammation and the postoperative acute phase response in patients undergoing elective coronary artery bypass grafting (CABG) assisted by cardiopulmonary bypass (CPB). CPB circuits contained either non-coated-

  15. History and Current Status of Robotic Totally Endoscopic Coronary Artery Bypass

    National Research Council Canada - National Science Library

    Lee, Jeffrey D; Srivastava, Mukta; Bonatti, Johannes


    Robotic totally endoscopic coronary artery bypass (TECAB) is a minimally invasive endoscopic surgical approach using the daVinci robotic telemanipulation system to perform coronary artery bypass grafting on the arrested or beating heart...

  16. DSP Control of Line Hybrid Active Filter

    DEFF Research Database (Denmark)

    Dan, Stan George; Benjamin, Doniga Daniel; Magureanu, R.


    Active Power Filters have been intensively explored in the past decade. Hybrid active filters inherit the efficiency of passive filters and the improved performance of active filters, and thus constitute a viable improved approach for harmonic compensation. In this paper a parallel hybrid filter ...... active filter. Simulation and experimental results obtained in laboratory confirmed the validity and effectiveness of the control.......Active Power Filters have been intensively explored in the past decade. Hybrid active filters inherit the efficiency of passive filters and the improved performance of active filters, and thus constitute a viable improved approach for harmonic compensation. In this paper a parallel hybrid filter...... is studied for current harmonic compensation. The hybrid filter is formed by a single tuned Le filter and a small-rated power active filter, which are directly connected in series without any matching transformer. Thus the required rating of the active filter is much smaller than a conventional standalone...

  17. Mechanical behavior of ceramic composite hot-gas filters after exposure to severe environments

    Energy Technology Data Exchange (ETDEWEB)

    Pysher, D.J.; Weaver, B.L.; Smith, R.G. [Ceramic Technology Center, St. Paul, MN (United States)] [and others


    A novel type of hot-gas filter based on a ceramic fiber reinforced ceramic matrix has been developed, as reported at previous Fossil Energy Materials Conferences, through research activities at Oak Ridge National Laboratory (ORNL) and at the 3M Company. Simulated testing has been done at the Westinghouse Science and Technology Center. This filter technology has been extended to full size, 60 mm OD by 1.5 meter long candle filters and a commercially viable process for producing the filters has been developed filters are undergoing testing and demonstration use throughout the world for applications in pressurized fluidized-bed combustion (PFBC) and integrated gasification combined cycle (IGCC) plants. Demonstration tests of this ceramic composite filter along with other filters are in progress at the Tidd PFBC plant Mechanical tests were performed on the 3 M brand Ceramic Composite Candle Filter after exposure to various corrosive environments in order to assess its ability to function as a hot gas filter in coal-fired applications. Due to the different construction of ceramic composite filters and the thin composite wall versus the typical thick-walled monolithic filter, standard mechanical property tests had to be refined or modified to accurately determine the filters properties. These tests and filter property results will be described Longitudinal tensile and diametral O-ring compression tests were performed on as-produced candle filters as well as on filters which had been exposed to various environments. The exposures were for 1000 hrs at 850{degrees}C in wet air, in wet air containing Na{sub 2}CO{sub 3}, and in wet air containing NaCl. In addition, a filter which bad been coated with ash (Old Grimethorpe) was exposed to wet air at 850{degrees}C for 1000 hours.

  18. Filter and Filter Bank Design for Image Texture Recognition

    Energy Technology Data Exchange (ETDEWEB)

    Randen, Trygve


    The relevance of this thesis to energy and environment lies in its application to remote sensing such as for instance sea floor mapping and seismic pattern recognition. The focus is on the design of two-dimensional filters for feature extraction, segmentation, and classification of digital images with textural content. The features are extracted by filtering with a linear filter and estimating the local energy in the filter response. The thesis gives a review covering broadly most previous approaches to texture feature extraction and continues with proposals of some new techniques. 143 refs., 59 figs., 7 tabs.

  19. Leukodepletion blood filters: filter design and mechanisms of leukocyte removal. (United States)

    Dzik, S


    Modern leukocyte removal filters have been developed after years of refinement in design. Current filters are composite filters in which synthetic microfiber material is prepared as a nonwoven web. The filter material may be surface modified to alter surface tension or charge to improve performance. The housing design promotes effective contact of blood with the filter material and decreases shear forces. The exact mechanisms by which these filters remove leukocytes from blood components are uncertain, but likely represent a combination of both physical and biological processes whose contributions to leukocyte removal are interdependent. Small-pore microfiber webs result in barrier phenomena that permit retention of individual cells and increase the total adsorptive area of the filter. Modifications in surface charge can increase or decrease cell attraction to the fibers. Optimum interfacial surface tensions between blood cells, plasma, and filter fibers not only permit effective blood flow through small fiber pores, but also facilitate cell contact with the material. Barrier retention is a common mechanism for all modern leukocyte-removal filters and applies to all leukocyte subtypes. Because barrier retention does not depend on cell viability, it is operative for cells of any age and will retain any nondeformable cell, including whole nuclei from lymphocytes or monocytes. Barrier retention is supplemented by retention by adhesion. RBCs, lymphocytes, monocytes, granulocytes, and platelets differ in their relative adhesiveness to filter fibers. Different adhesive mechanisms are used in filters designed for RBCs compared with filters designed for platelets. Although lymphocytes, monocytes, and granulocytes can adhere directly to filter fibers, the biological mechanisms underlying cell adhesion may differ for these cell types. These differences may depend on expression of cell adhesion molecules. In the case of filtration of fresh RBCs, platelet-leukocyte interaction

  20. Tandem HEPA filter tests. (United States)

    Schuster, B G; Osetek, D J


    Current methods for evaluating the performance and reliability of high-efficiency air cleaning systems use forward light-scattering photometers and DOP aerosol. This method is limited to measuring protection factors of 10(4) or 10(5) and has poor sensitivity to particles less than .3 micron. More accurate determination of system performance could be made by measuring two filter stages with a single test. Because of the large protection factors of a two-stage system, it is necessary to use high challenge aerosol concentrations and long downstream sampling times. Concentrations were measured using an intra-cavity laser light-scattering aerosol spectrometer which is capable of detection of single particles ranging in size from 0.07 to 3.00 micron diameter. The results of several tests with challenge aerosols of both NaCl and DOP yielded protection factors ranging from 1.4 x 10(7) to 3.0 x 10(9) for two HEPA filters in series.

  1. [Prevalence of early and late dumping after gastric bypass]. (United States)

    Héraïef, R; Giusti, V


    Gastric bypass surgery is an effective treatment of obesity, bringing a significant weight loss and a major improvement of carbohydrate profile. However, in some patients, a deregulation in carbohydrate metabolism between insulin secretion and sensitivity is observed, whereupon early and late dumping happen. Their prevalence isn't well studied, although it seems that 10 to 20% of patients are affected. We've studied a cohort of 70 patients who undergone gastric bypass surgery at the CHUV. 18 (25.7%) patients have a positive anamnesis for early dumping and 10 (14.3%) for late dumping, being it superior as what is described in the literature.

  2. Arteriovenous fistulas aggravate the hemodynamic effect of vein bypass stenoses

    DEFF Research Database (Denmark)

    Nielsen, Tina G; Djurhuus, Christian Born; Morre-Pedersen, Erik


    Doppler spectra obtained 10 cm downstream of the fistula. All measurements were carried out with open and clamped fistula. RESULTS: At 30% diameter reducing stenosis opening of the fistula induced a 12% systolic pressure drop across the stenosis but had no adverse effect on the Doppler waveform parameters......PURPOSE: The purpose of this study was to assess the impact of arteriovenous fistulas combined with varying degrees of stenosis on distal bypass hemodynamics and Doppler spectral parameters. METHODS: In an in vitro flow model bypass stenoses causing 30%, 55%, and 70% diameter reduction were induced...

  3. Dextrocardia with situs inversus totalis: coronary artery bypass grafting. (United States)

    Hashmi, Salila; Anis, Mariam; Darr, Umer


    Dextrocardia with situs inversus is a rare congenital abnormality involving a left-handed mal rotation of the visceral organs. The incidence of coronary artery disease is the same as that in the general population. Performing coronary artery bypass surgery on patients with dextrocardia poses a more challenging task. It is recommended that the right internal mammary artery be the first choice of graft for the anterior descending artery for a "situs inversus" situation. We report 2 cases of patients with Dextrocardia who developed coronary artery disease and underwent coronary artery bypass grafting. Also mentioned is the slight difference in our technique.

  4. Transparent graphene microstrip filters for wireless communications (United States)

    Wang, Jinchen; Guan, Yifei; Yu, Hua; Li, Na; Wang, Shuopei; Shen, Cheng; Dai, Zhijiang; Gan, Decheng; Yang, Rong; He, Songbai; Zhang, Guangyu


    A microstrip is an indispensable component for wireless communication circuits. With the development of 5G technology, optically transparent microstrip filters urgently need to be developed. In this work, we have theoretically and experimentally demonstrated the immense potential of graphene microstrips for transparent wireless communication circuits in the 5G era. Both wideband and dual-band transparent graphene microstrip filters have shown more than 80% optical transmissivity in the region from 250 nm to 2000 nm with good frequency responses. S and C band microwave signals can transmit along the graphene microstrip lines effectively while coupling excitations produce relatively large insertion losses. Our results show that transparent microstrips designed with high-quality graphene will largely scale down the size of the wireless devices and thus play an irreplaceable role in the 5G era.

  5. Spatial filters for high average power lasers (United States)

    Erlandson, Alvin C


    A spatial filter includes a first filter element and a second filter element overlapping with the first filter element. The first filter element includes a first pair of cylindrical lenses separated by a first distance. Each of the first pair of cylindrical lenses has a first focal length. The first filter element also includes a first slit filter positioned between the first pair of cylindrical lenses. The second filter element includes a second pair of cylindrical lenses separated by a second distance. Each of the second pair of cylindrical lenses has a second focal length. The second filter element also includes a second slit filter positioned between the second pair of cylindrical lenses.

  6. Note: cryogenic coaxial microwave filters. (United States)

    Tancredi, G; Schmidlin, S; Meeson, P J


    The careful filtering of microwave electromagnetic radiation is critical for controlling the electromagnetic environment for experiments in solid-state quantum information processing and quantum metrology at millikelvin temperatures. We describe the design and fabrication of a coaxial filter assembly and demonstrate that its performance is in excellent agreement with theoretical modelling. We further perform an indicative test of the operation of the filters by making current-voltage measurements of small, underdamped Josephson junctions at 15 mK.

  7. Multi-filter spectrophotometry simulations (United States)

    Callaghan, Kim A. S.; Gibson, Brad K.; Hickson, Paul


    To complement both the multi-filter observations of quasar environments described in these proceedings, as well as the proposed UBC 2.7 m Liquid Mirror Telescope (LMT) redshift survey, we have initiated a program of simulated multi-filter spectrophotometry. The goal of this work, still very much in progress, is a better quantitative assessment of the multiband technique as a viable mechanism for obtaining useful redshift and morphological class information from large scale multi-filter surveys.

  8. Faraday anomalous dispersion optical filters (United States)

    Shay, T. M.; Yin, B.; Alvarez, L. S.


    The effect of Faraday anomalous dispersion optical filters on infrared and blue transitions of some alkali atoms is calculated. A composite system is designed to further increase the background noise rejection. The measured results of the solar background rejection and image quality through the filter are presented. The results show that the filter may provide high transmission and high background noise rejection with excellent image quality.

  9. On-pump versus off-pump coronary artery bypass surgery

    DEFF Research Database (Denmark)

    Houlind, Kim Christian


    Off pump coronary artery bypass surgery has been purported to be safer than conventional coronary artery bypass surgery performed using cardiopulmonary bypass. This theory was supported by a number of early series, but failed to be confirmed by a number of small, randomized controlled trials...

  10. On-Pump Versus Off-Pump Coronary Artery Bypass Surgery in Elderly Patients

    DEFF Research Database (Denmark)

    Houlind, Kim; Kjeldsen, Bo Juul; Madsen, Susanne Nørgaard


    Conventional coronary artery bypass grafting performed with the use of cardiopulmonary bypass is a well-validated treatment for patients with ischemic heart disease. Off-pump coronary artery bypass grafting (OPCAB) has been suggested to reduce the number of perioperative complications, especially...

  11. Fabrication of nanofiber non-wovens on the melt blowing die with air by-passes


    Chen Ting; Yang Kang; Wu Li-Li


    The air flow field of the melt blowing die with air by-passes is simulated. The results show that fibers fabricated on the die with air by-passes are much finer than those without air by-passes, which indicates an energy-saving approach to fabricating nanofibers on the melt blowing equipment.

  12. Fabrication of nanofiber non-wovens on the melt blowing die with air by-passes

    Directory of Open Access Journals (Sweden)

    Chen Ting


    Full Text Available The air flow field of the melt blowing die with air by-passes is simulated. The results show that fibers fabricated on the die with air by-passes are much finer than those without air by-passes, which indicates an energy-saving approach to fabricating nanofibers on the melt blowing equipment.

  13. Natural headland sand bypassing; towards identifying and modelling the mechanisms and processes

    NARCIS (Netherlands)

    Bin Ab Razak, M.S.


    Natural headland sand bypassing: Towards identifying and modelling the mechanisms and processes contributes to the understanding of the mechanisms and processes of sand bypassing in artificial and non-artificial coastal environments through a numerical modelling study. Sand bypassing processes in

  14. 21 CFR 870.4210 - Cardiopulmonary bypass vascular catheter, cannula, or tubing. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass vascular catheter, cannula... Devices § 870.4210 Cardiopulmonary bypass vascular catheter, cannula, or tubing. (a) Identification. A cardiopulmonary bypass vascular catheter, cannula, or tubing is a device used in cardiopulmonary surgery to...

  15. 21 CFR 870.4290 - Cardiopulmonary bypass adaptor, stopcock, manifold, or fitting. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass adaptor, stopcock, manifold... Devices § 870.4290 Cardiopulmonary bypass adaptor, stopcock, manifold, or fitting. (a) Identification. A cardiopulmonary bypass adaptor, stopcock, manifold, or fitting is a device used in cardiovascular diagnostic...

  16. 21 CFR 870.4340 - Cardiopulmonary bypass level sensing monitor and/or control. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass level sensing monitor and... Devices § 870.4340 Cardiopulmonary bypass level sensing monitor and/or control. (a) Identification. A cardiopulmonary bypass level sensing monitor and/or control is a device used to monitor and/or control the level...

  17. 21 CFR 870.4330 - Cardiopulmonary bypass on-line blood gas monitor. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass on-line blood gas monitor. 870.4330 Section 870.4330 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Cardiopulmonary bypass on-line blood gas monitor. (a) Identification. A cardiopulmonary bypass on-line blood gas...

  18. 21 CFR 870.4220 - Cardiopulmonary bypass heart-lung machine console. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass heart-lung machine console. 870.4220 Section 870.4220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Cardiopulmonary bypass heart-lung machine console. (a) Identification. A cardiopulmonary bypass heart-lung machine...

  19. 21 CFR 870.4360 - Nonroller-type cardiopulmonary bypass blood pump. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nonroller-type cardiopulmonary bypass blood pump... Nonroller-type cardiopulmonary bypass blood pump. (a) Identification. A nonroller-type cardiopulmonary bypass blood pump is a device that uses a method other than revolving rollers to pump the blood through...

  20. 21 CFR 870.4370 - Roller-type cardiopulmonary bypass blood pump. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Roller-type cardiopulmonary bypass blood pump. 870... Roller-type cardiopulmonary bypass blood pump. (a) Identification. A roller-type cardiopulmonary bypass blood pump is a device that uses a revolving roller mechanism to pump the blood through the...

  1. 21 CFR 870.4410 - Cardiopulmonary bypass in-line blood gas sensor. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass in-line blood gas sensor... Cardiopulmonary bypass in-line blood gas sensor. (a) Identification. A cardiopulmonary bypass in-line blood gas sensor is a transducer that measures the level of gases in the blood. (b) Classification. Class II...

  2. Bowtie filters for dedicated breast CT: Analysis of bowtie filter material selection

    Energy Technology Data Exchange (ETDEWEB)

    Kontson, Kimberly, E-mail:; Jennings, Robert J. [Department of Bioengineering, University of Maryland, College Park, Maryland 20742 and Division of Imaging and Applied Mathematics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993 (United States)


    , and scatter were investigated. Results: Analytical calculations with and without each bowtie filter show that some materials for a given design produce bowtie filters that are too large for implementation in breast CT scanners or too small to accurately manufacture. Results also demonstrate the ability to manipulate the energy fluence distribution (dynamic range) by using different materials, or different combinations of materials, for a given bowtie filter design. This feature is especially advantageous when using photon counting detector technology. Monte Carlo simulation results from PENELOPE show that all studied material choices for bowtie design #2 achieve nearly uniform dose distribution, noise uniformity index less than 5%, and nearly uniform scatter-to-primary ratio. These same features can also be obtained using certain materials with bowtie designs #1 and #3. Conclusions: With the three bowtie filter designs used in this work, the selection of material is an important design consideration. An appropriate material choice can improve image quality, dose uniformity, and dynamic range.

  3. Adaptive filtering and change detection

    CERN Document Server

    Gustafsson, Fredrik


    Adaptive filtering is a classical branch of digital signal processing (DSP). Industrial interest in adaptive filtering grows continuously with the increase in computer performance that allows ever more conplex algorithms to be run in real-time. Change detection is a type of adaptive filtering for non-stationary signals and is also the basic tool in fault detection and diagnosis. Often considered as separate subjects Adaptive Filtering and Change Detection bridges a gap in the literature with a unified treatment of these areas, emphasizing that change detection is a natural extensi

  4. Limits of search filter development. (United States)

    Wilczynski, Nancy L; Lokker, Cynthia; McKibbon, Kathleen Ann; Hobson, Nicholas; Haynes, R Brian


    The research attempted to develop search filters for biomedical literature databases that improve retrieval of studies of clinical relevance for the nursing and rehabilitation professions. Diagnostic testing framework compared machine-culled and practitioner-nominated search terms with a hand-tagged clinical literature database. We were unable to: (1) develop filters for nursing, likely because of the overlapping and expanding scope of practice for nurses in comparison with medical professionals, or (2) develop filters for rehabilitation, because of its broad scope and the profession's multifaceted understanding of "health and ability." We found limitations on search filter development for these health professions: nursing and rehabilitation.

  5. The intractable cigarette 'filter problem'. (United States)

    Harris, Bradford


    When lung cancer fears emerged in the 1950s, cigarette companies initiated a shift in cigarette design from unfiltered to filtered cigarettes. Both the ineffectiveness of cigarette filters and the tobacco industry's misleading marketing of the benefits of filtered cigarettes have been well documented. However, during the 1950s and 1960s, American cigarette companies spent millions of dollars to solve what the industry identified as the 'filter problem'. These extensive filter research and development efforts suggest a phase of genuine optimism among cigarette designers that cigarette filters could be engineered to mitigate the health hazards of smoking. This paper explores the early history of cigarette filter research and development in order to elucidate why and when seemingly sincere filter engineering efforts devolved into manipulations in cigarette design to sustain cigarette marketing and mitigate consumers' concerns about the health consequences of smoking. Relevant word and phrase searches were conducted in the Legacy Tobacco Documents Library online database, Google Patents, and media and medical databases including ProQuest, JSTOR, Medline and PubMed. 13 tobacco industry documents were identified that track prominent developments involved in what the industry referred to as the 'filter problem'. These reveal a period of intense focus on the 'filter problem' that persisted from the mid-1950s to the mid-1960s, featuring collaborations between cigarette producers and large American chemical and textile companies to develop effective filters. In addition, the documents reveal how cigarette filter researchers' growing scientific knowledge of smoke chemistry led to increasing recognition that filters were unlikely to offer significant health protection. One of the primary concerns of cigarette producers was to design cigarette filters that could be economically incorporated into the massive scale of cigarette production. The synthetic plastic cellulose acetate


    The Wet-Weather Flow Technologies Pilot of the EPA's Technology Verification (ETV) Program under a partnership with NSF International has verified the performawnce of the USFilter/Stranco Products chemical induction mixer used for disinfection of wet-weather flows. The USFilter t...

  7. Reconfigurable RF Filters Project (United States)

    National Aeronautics and Space Administration — Space Micro proposes to build upon our existing space microelectronics and hardening technologies and products, to research and develop a novel rad hard/tolerant RF...

  8. Bridging the ensemble Kalman filter and particle filters

    Energy Technology Data Exchange (ETDEWEB)

    Stordal, Andreas Stoerksen; Karlsen, Hans A.; Naevdal, Geir; Skaug, Hans J.; Valles, Brice


    The nonlinear filtering problem occurs in many scientific areas. Sequential Monte Carlo solutions with the correct asymptotic behavior such as particle filters exist but they are computationally too expensive when working with high-dimensional systems. The ensemble Kalman filter is a more robust method that has shown promising results with a small sample size but the samples are not guaranteed to come from the true posterior distribution. By approximating the model error with Gaussian kernels we get the advantage of both a Kalman correction and a weighting step. The resulting Gaussian mixture filter has the advantage of both a local Kalman type correction and the weighting/re sampling step of a particle filter. The Gaussian mixture approximation relies on a tunable bandwidth parameter which often has to be kept quite large in order to avoid weight collapse in high dimensions. As a result, the Kalman correction is too large to capture highly non-Gaussian posterior distributions. In this paper we have extended the Gaussian mixture filter (Hoteit et al., 2008b) and also made the connection to particle filters more transparent. In particular we introduce a tuning parameter for the importance weights. In the last part of the paper we have performed a simulation experiment with the Lorenz40 model where our method has been compared to the EnKF and a full implementation of a particle filter. The results clearly indicate that the new method has advantages compared to the standard EnKF. (Author)

  9. Kalman Filter Desing, Smoothing and Analysis


    Cederkvist, Henrik Rene


    Thesis is based on three different aspects of Kalman filtering. >Kalman filters for navigation. Investigate the difference between a Extended Kalman Filter and a Linearized Kalman Filter with feedback. And show how different system models relate to these Kalman Filters when implemented in a filter. >Smoothing. Investigate how much there is to be gained from smoothing. We will only look at the fixed-interval smoother, using the method of forward and backward filtering. ...

  10. Manufacturing a low-cost ceramic water filter and filter system for the elimination of common pathogenic bacteria (United States)

    Simonis, J. J.; Basson, A. K.

    Africa is one of the most water-scarce continents in the world but it is the lack of potable water which results in diarrhoea being the leading cause of death amongst children under the age of five in Africa (696 million children under 5 years old in Africa contract diarrhoea resulting in 2000 deaths per day: WHO and UNICEF, 2009). Most potable water treatment methods use bulk water treatment not suitable or available to the majority of rural poor in Sub-Saharan Africa. One simple but effective way of making sure that water is of good quality is by purifying it by means of a household ceramic water filter. The making and supply of water filters suitable for the removal of suspended solids, pathogenic bacteria and other toxins from drinking water is therefore critical. A micro-porous ceramic water filter with micron-sized pores was developed using the traditional slip casting process. This locally produced filter has the advantage of making use of less raw materials, cost, labour, energy and expertise and being more effective and efficient than other low cost produced filters. The filter is fitted with a silicone tube inserted into a collapsible bag that acts as container and protection for the filter. Enhanced flow is obtained through this filter system. The product was tested using water inoculated with high concentrations of different bacterial cultures as well as with locally polluted stream water. The filter is highly effective (log10 > 4 with 99.99% reduction efficiency) in providing protection from bacteria and suspended solids found in natural water. With correct cleaning and basic maintenance this filter technology can effectively provide drinking water to rural families affected by polluted surface water sources. This is an African solution for the more than 340 million people in Africa without access to clean drinking water (WHO and UNICEF, 2008).

  11. Myocardial ischaemia during coronary artery bypass graft surgery: a ...

    African Journals Online (AJOL)

    Multiorgan dysfunction as a result of the effects of the neurohumoral system, triggered by surgery, anaesthesia, cardiopulmonary bypass, hypothermia and blood transfusion, can lead to prolonged intensive care unit and hospital stay. In this article, a literature review was embarked upon, to understand the pathophysiology ...

  12. Return to the workforce following coronary artery bypass grafting

    DEFF Research Database (Denmark)

    Butt, Jawad H; Rørth, Rasmus; Kragholm, Kristian


    BACKGROUND: Returning to the workforce after coronary artery bypass grafting (CABG) holds important socioeconomic consequences not only for patients, but the society as well. Yet data on this issue are limited. We examined return to the workforce and associated factors in patients of working age...

  13. The effect of bypass protein supplementation on the reproductive ...

    African Journals Online (AJOL)


    Short paper and poster abstracts: 38th Congress of the South African Society of Animal Science. The South African Journal of Animal Science is available online at 60. The effect of bypass protein supplementation on the reproductive performance of. Merino sheep grazing mixed karoo veld.

  14. Blood concentrations of cefuroxime in cardiopulmonary bypass surgery

    NARCIS (Netherlands)

    Bertholee, Daphne; ter Horst, Peter G. J.; Hijmering, Michel L.; Spanjersberg, Alexander J.; Hospes, Wobbe; Wilffert, Bob


    Objectives Patients with coronary artery bypass graft (CABG) surgery are at risk for severe postoperative infections. Prophylactic cefuroxime may help to reduce this risk, however sufficient concentrations, i.e. above the breakpoint (32 mg/L), are mandatory. The aim of this study is to evaluate the

  15. Angina pectoris, one to 10 years after aortocoronary bypass surgery

    NARCIS (Netherlands)

    K. Laird-Meeter; H.J. ten Katen (Harald); R.W. Brower (Ronald); M.J.B.M. van den Brand (Marcel); P.W.J.C. Serruys (Patrick); M.M.P. Haalebos (Max); E. Bos (Egbert); P.G. Hugenholtz (Paul)


    textabstractThe incidence of angina pectoris (AP) after bypass surgery was assessed in 1041 patients operated on consecutively between 1971 and 1980. Of the 977 survivors, 920 (94%) participated in the study with a followup time varying from 1 to 10 years (mean 3.5 years). Post-operative angina

  16. Positive maternal and foetal outcomes after cardiopulmonary bypass ...

    African Journals Online (AJOL)

    This case study describes the successful management of a parturient with severe mitral stenosis and moderate mitral regurgitation who underwent cardiopulmonary bypass (CPB) surgery. A healthy baby was delivered by Caesarean section 11 days later. The effects of CPB surgery and mitral valve replacement on ...

  17. Emergency bypass post percutaneous atrial ablation: a case report.

    LENUS (Irish Health Repository)

    Hargrove, M


    A 34-year-old male undergoing percutaneous atrial ablation procedure for paroxysmal fibrillation required emergency sternotomy for cardiac tamponade. The patient had been anticoagulated and had received plavix and aspirin prior to and during the ablation procedure. Seven units of red cell concentrate had been transfused in the cardiac catherisation laboratory. On arrival in theatre, the patient was hypotensive, but was awake on induction of anaesthesia. No recordable blood pressure with non-invasive monitoring was observed. A sternotomy was immediately performed and, on evacuation of the pericardium, a bleeding site was not visible. The patient was commenced on cardiopulmonary bypass. Bleeding site was identified and the defect closed. The patient was weaned from cardiopulmonary bypass with minimal inotropic support and made an uneventful recovery. Bypass time was 38 minutes. A literature review showed a 1% incidence of post-ablation bleeding(1). The incidence of reverting to bypass for such an event has not been reported previously. During these procedures, it might be wise to have the cardiothoracic team notified while atrial ablation procedures are being performed in the cardiac catheterization laboratory.

  18. Incidence and aetiology of a raised hemidiaphragm after cardiopulmonary bypass. (United States)

    Large, S R; Heywood, L J; Flower, C D; Cory-Pearce, R; Wallwork, J; English, T A


    A raised hemidiaphragm has been reported as an uncommon complication of cardiopulmonary bypass, possibly resulting from cold injury to the phrenic nerve. At Papworth Hospital myocardial protection during cardiac arrest relies in part on irrigation of the pericardial cavity with large volumes of Hartmann's solution at 4 degrees C. Retrospective review of the chest radiographs of 100 consecutive patients undergoing cardiopulmonary bypass showed that 31 had a raised left hemidiaphragm soon after operation. The only significant correlation was with aortic cross clamp time (p less than 0.03). A prospective study of 36 consecutive patients undergoing cardiopulmonary bypass was then undertaken with diaphragmatic screening and chest radiography. Preoperative screening gave normal results in all patients. In the early postoperative period 16 (44%) had left diaphragmatic weakness or paralysis, two (5.5%) right sided weakness, and two (5.5%) bilateral weakness. Repeat screening of these patients showed resolution in all but four cases (80%) at six months and in all but two (90%) at one year. The greater number of left sided lesions than of right (8:1) is probably due to the fact that the cold jet of irrigating fluid is directed towards the left phrenic nerve. These findings have implications with regard to the optimum temperature of the irrigant fluid for myocardial protection during cardiopulmonary bypass. PMID:4024004

  19. Difficult Tracheal Intubation in Obese Gastric Bypass patients

    DEFF Research Database (Denmark)

    Dohrn, Niclas; Sommer, Thorbjørn; Bisgaard, J.


    undergoing gastric bypass. Tracheal intubation was done preoperatively together with scoring of Intubation Score (IS), Mallampati (MLP), and Cormack-Lehane classification (CLC) and registration of the quantities of anesthetics and total attempts on cannulation. The overall proportion of patients with DTI...

  20. Bypassing of a barrier by dissociated and superlattice dislocations

    DEFF Research Database (Denmark)

    Bhushan, Karihaloo


    Very simple procedures are used to calculate the upper and lower bounds for the applied stress required for the leading extended (superlattice) dislocation in a group of n coplanar screw dislocations of like sign with Burgers vector b to bypass a noncoplanar perfect screw dislocation with Burgers...

  1. Gastrointestinal motility during cardiopulmonary bypass : A sonomicrometric study

    NARCIS (Netherlands)

    Gu, YJ; de Kroon, TL; Elstrodt, JM; Rakhorst, G

    Cardiopulmonary bypass (CPB) is known to impair the integrity of the gastrointestinal tract. However, little is known about the movement behavior of the gastrointestinal tract during CPB. This study was aimed to assess the gastrointestinal motility with sonomicrometry, a distance measurement using

  2. Differential effects of gastric bypass and banding on the ...

    African Journals Online (AJOL)

    Hala Mourad Demerdash


    Sep 1, 2012 ... Abstract Background: Weight loss (5–10%) improves obesity-associated cardiovascular risk factors. The aim of this work was to study the effect of 2 commonly performed bariatric surgical procedures; laparoscopic Roux-en-Y gastric bypass (RYGBP) and laparoscopic gastric band. (BAND), on the ...

  3. Differential effects of gastric bypass and banding on the ...

    African Journals Online (AJOL)

    Background: Weight loss (5–10%) improves obesity-associated cardiovascular risk factors. The aim of this work was to study the effect of 2 commonly performed bariatric surgical procedures; laparoscopic Roux-en-Y gastric bypass (RYGBP) and laparoscopic gastric band (BAND), on the cardiovascular risk profile in ...

  4. Combined Open-Heart Coronary Artery Bypass Surgery and ...

    African Journals Online (AJOL)

    CASE DETAILS: A 54-year-old woman suffering from dyspnea, chest pain and decreased left ventricular function (EF=40%) was diagnosed with coronary artery disease (3 vessel disease) and became candidate for coronary artery bypass grafting (CABG). Also, she had multinodular goiter with normal thyroid function test.

  5. Predicting the need for blood during cardiopulmonary bypass ...

    African Journals Online (AJOL)

    Methods: An equation for prediction of HctCPB (Hctpred), based on weight and pre-operative haemoglobin concentration was used to forecast which patients would develop HctCPB < 20%. ... Key Words: Haematocrit, Blood transfusion, Autologous, Cardiopulmonary bypass, ROC curve, Predictive value of tests. Southern ...

  6. Particle Kalman Filtering: A Nonlinear Framework for Ensemble Kalman Filters

    KAUST Repository

    Hoteit, Ibrahim


    Optimal nonlinear filtering consists of sequentially determining the conditional probability distribution functions (pdf) of the system state, given the information of the dynamical and measurement processes and the previous measurements. Once the pdfs are obtained, one can determine different estimates, for instance, the minimum variance estimate, or the maximum a posteriori estimate, of the system state. It can be shown that, many filters, including the Kalman filter (KF) and the particle filter (PF), can be derived based on this sequential Bayesian estimation framework. In this contribution, we present a Gaussian mixture‐based framework, called the particle Kalman filter (PKF), and discuss how the different EnKF methods can be derived as simplified variants of the PKF. We also discuss approaches to reducing the computational burden of the PKF in order to make it suitable for complex geosciences applications. We use the strongly nonlinear Lorenz‐96 model to illustrate the performance of the PKF.

  7. The ecological filter system for treatment of decentralized wastewater. (United States)

    Zhong, Kun; Luo, Yi-Yong; Wu, Zheng-Song; He, Qiang; Hu, Xue-Bin; Jie, Qi-Wu; Li, Yan-Ting; Wang, Shao-Jie


    A vertical flow constructed wetland was combined with a biological aerated filter to develop an ecological filter, and to obtain the optimal operating parameters: The hydraulic loading was 1.55 m3/(m2·d), carbon-nitrogen ratio was 10, and gas-water ratio was 6. The experimental results demonstrated considerable removal efficiency of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), total nitrogen (TN), and total phosphorus (TP) in wastewater by the ecological filter, with average removal rates of 83.79%, 93.10%, 52.90%, and 79.07%, respectively. Concentration of NH4+-N after treatment met the level-A discharge standard of GB18918-2002. Compared with non-plant filter, the ecological filter improved average removal efficiency of COD, NH4+-N, TN, and TP by 13.03%, 25.30%, 14.80%, and 2.32%, respectively: thus, plants significantly contribute to the removal of organic pollutants and nitrogen. Through microporous aeration and O2 secretion of plants, the ecological filter formed an aerobic-anaerobic-aerobic alternating environment; thus aerobic and anaerobic microbes were active and effectively removed organic pollutants. Meanwhile, nitrogen and phosphorus were directly assimilated by plants and as nutrients of microorganisms. Meanwhile, pollutants were removed through nitrification, denitrification, filtration, adsorption, and interception by the filler. High removal rates of pollutants on the ecological filter proved that it is an effective wastewater-treatment technology for decentralized wastewater of mountainous towns.

  8. Oriented diffusion filtering for enhancing low-quality fingerprint images

    KAUST Repository

    Gottschlich, C.


    To enhance low-quality fingerprint images, we present a novel method that first estimates the local orientation of the fingerprint ridge and valley flow and next performs oriented diffusion filtering, followed by a locally adaptive contrast enhancement step. By applying the authors\\' new approach to low-quality images of the FVC2004 fingerprint databases, the authors are able to show its competitiveness with other state-of-the-art enhancement methods for fingerprints like curved Gabor filtering. A major advantage of oriented diffusion filtering over those is its computational efficiency. Combining oriented diffusion filtering with curved Gabor filters led to additional improvements and, to the best of the authors\\' knowledge, the lowest equal error rates achieved so far using MINDTCT and BOZORTH3 on the FVC2004 databases. The recognition performance and the computational efficiency of the method suggest to include oriented diffusion filtering as a standard image enhancement add-on module for real-time fingerprint recognition systems. In order to facilitate the reproduction of these results, an implementation of the oriented diffusion filtering for Matlab and GNU Octave is made available for download. © 2012 The Institution of Engineering and Technology.

  9. Development of particle filters for ships; Udvikling af partikelfiltre til skibe

    Energy Technology Data Exchange (ETDEWEB)

    Jakobsen, O.; Norre Holm, J.; Koecks, M. [Teknologisk Institut, Aarhus (Denmark)


    The project has resulted in a solution with a well-functioning maritime particle filter which reduces the particle emission significantly. The visible smoke from the vessels funnel, which typically is seen while manoeuvring in the harbour, is also reduced to a minimum. The system is constructed in such a way that the exhaust gases can be bypassed around the filter unit, in this situation to ensure the engines operation in case of filter clogging. The system has been provided with safety functions to prevent an excessive exhaust gas back-pressure and there are fitted remote controlled exhaust valves. Some of the challenges in the project have been the requirement from the engine manufacturer of keeping a low turbocharger back-pressure, besides the space conditions aboard the test vessel and the achievement of sufficient temperatures for regeneration of the particle filter. To oppose the requirement of low exhaust gas back-pressure, the filter housing was designed with space for twice as many monoliths as originally planned. In the funnel casing the original installations were removed to make space for the filter housing, and the system was enlarged with electrically controlled exhaust valves to improve the daily operation of the crew. The regeneration issue was solved by mounting electric automatically controlled heating elements in the filter housing and by an ash exhaust system. Regeneration is carried out by the crew when the vessel lies in harbour in the evening after the last tour of the day. Before mounting the particle filter, measurements were carried out aboard, showing a compound of particle emissions with an expected high NO{sub x}-level of 8.33 g/kW, whereas the other emissions were lower than expected at first. Especially HC and CO were very low, but also the particle mass (PM) had a relatively low value of 0.22 g/kWh. After commissioning the particle filter, a significant reduction of 93% of the particle number (N) was observed. A reduction in N was

  10. Evolution of the concept of oxygen transport in the critically ill, with a focus on children after cardiopulmonary bypass. (United States)

    Li, Jia


    The concept of oxygen transport, defined as the relation between oxygen consumption (VO2) and delivery (DO2), is of fundamental importance in critically ill patients. The past 200 years have witnessed a stepwise progressive improvement in the understanding of pathophysiological disturbances in the balance of DO2 and VO2 in critically ill patients including those after cardiopulmonary bypass surgery. Intermittent spectacular technological achievements have accelerated the rate of progress. Therapeutic advances have been particularly impressive during the recent decades. Examination of the relation between DO2 and VO2 provides a useful framework around which the care of the critically ill may be developed. Until now, only a few groups have used this framework to examine children after cardiopulmonary bypass. The key topics that will be covered in this review article are the evolution of the concept from its early development to its present, increasingly sophisticated, role in the management of critically ill patients, with a focus on children after cardiopulmonary bypass surgery.

  11. Bypass Surgery after Endovascular Therapy for Infrapopliteal Lesion Is Not a Poor Outcome Compared with Initial Bypass Surgery by Vascular Surgeons. (United States)

    Morisaki, Koichi; Yamaoka, Terutoshi; Iwasa, Kazuomi; Ohmine, Takahiro


    It is unclear whether prior endovascular therapy (EVT) adversely affects bypass surgery. The aim of this study is to investigate treatment outcomes between initial bypass (bypass-first) and bypass surgery after EVT (EVT-first). We conducted a retrospective analysis of critical limb ischemia patients undergoing infrapopliteal bypass between November 2006 and December 2015. Graft patency, limb salvage (LS), amputation-free survival (AFS), and overall survival (OS) were examined between bypass-first and EVT-first groups. The subjects in this study were 75 patients and 82 limbs in the bypass-first group and 24 patients and 24 limbs in the EVT-first group. The average age was higher in EVT-first group (P = 0.03). The percentage of inframalleolar bypass was higher in the EVT-first group (P = 0.002). Primary patency at 1 and 2 years was 72.0% and 67.5% for the bypass-first group and 53.1% and 47.2% for the EVT-first group, respectively (P = 0.04). Inframalleolar bypass was a risk factor for lower primary patency (hazard ratio 3.07, 95% confidence interval 1.18-8.51, P = 0.02) in multivariate analysis, while there were no differences in secondary patency, LS, AFS, and OS. Bypass surgery after EVT has lower primary patency rates in comparison with primary bypass in patients submitted to infrapopliteal revascularization. Although very heterogeneous study population with a lot of bias in the indication of the revascularization, LS, OS and AFS are not affected by previous EVT. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Cardiopulmonary bypass increases the risk of vasoplegic syndrome after coronary artery bypass grafting in patients with dialysis-dependent chronic renal failure

    Directory of Open Access Journals (Sweden)

    Nelson Américo Hossne Junior


    Full Text Available Abstract Objective: Coronary artery bypass grafting is currently the best treatment for dialysis patients with multivessel coronary artery involvement. Vasoplegic syndrome of inflammatory etiology constitutes an important postoperative complication, with highly negative impact on prognosis. Considering that these patients have an intrinsic inflammatory response exacerbation, our goal was to evaluate the incidence and mortality of vasoplegic syndrome after myocardial revascularization in this group. Methods: A retrospective, single-center study of 50 consecutive and non-selected dialysis patients who underwent myocardial revascularization in a tertiary university hospital, from 2007 to 2012. The patients were divided into 2 groups, according to the use of cardiopulmonary bypass or not (off-pump coronary artery bypass. The incidence and mortality of vasoplegic syndrome were analyzed. The subgroup of vasoplegic patients was studied separately. Results: There were no preoperative demographic differences between the cardiopulmonary bypass (n=20 and off-pump coronary artery bypass (n=30 group. Intraoperative data showed a greater number of distal coronary arteries anastomosis (2.8 vs. 1.8, P<0.0001 and higher transfusion rates (65% vs. 23%, P=0.008 in the cardiopulmonary bypass group. Vasoplegia incidence was statistically higher (P=0.0124 in the cardiopulmonary bypass group (30% compared to the off-pump coronary artery bypass group (3%. Vasoplegia mortality was 50% in the cardiopulmonary bypass group and 0% in the off-pump coronary artery bypass group. The vasoplegic subgroup analysis showed no statistically significant clinical differences. Conclusion: Cardiopulmonary bypass increased the risk for developing postoperative vasoplegic syndrome after coronary artery bypass grafting in patients with dialysis-dependent chronic renal failure.

  13. Comparison of 4% Succinylated Gelatin with 6% Hydroxyethyl Starch 130/0.4 for Preloading Prior to Cardiopulmonary Bypass in Coronary Artery Bypass Grafting Patients


    Deshmukh, Amit; Dave, Sona; Gujjar, Pinakin


    Aims and Objective: The present study was carried out with an objective to compare 4% succinylated gelatin with 6% hydroxyethyl starch 130/0.4 for preloading prior to cardiopulmonary bypass in coronary artery bypass grafting patients with respect to haemodynamics status, blood loss, transfusion requirement, ICU stay and complication. Methods: The study enrolling 60 patients of either sex, aged between 30-70 years undergoing elective coronary artery bypass grafting. These patients were randoml...

  14. Aquatic Plant/microbial Filters for Treating Septic Tank Effluent (United States)

    Wolverton, B. C.


    The use of natural biological processes for treating many types of wastewater have been developed by NASA at the John C. Stennis Space Center, NSTL, Mississippi, during the past 15 years. The simplest form of this technology involves the use of aquatic plant/marsh filters for treatment of septic tank effluent. Septic tank effluent from single home units can be treated to advanced secondary levels and beyond by using a 37.2 sq m (400 sq ft) surface area washed gravel filter. This filter is generally 0.3 m (1 ft) deep with a surface cover of approximately 0.15 m (6 in.) of gravel. The plants in this filter are usually aesthetic or ornamental such as calla lily (Zantedeschia aethiopica), canna lily (Canna flaccida), elephant ear (Colocasia esculenta), and water iris (Iris pseudacorus).

  15. Filter Media Tests Under Simulated Martian Atmospheric Conditions (United States)

    Agui, Juan H.


    Human exploration of Mars will require the optimal utilization of planetary resources. One of its abundant resources is the Martian atmosphere that can be harvested through filtration and chemical processes that purify and separate it into its gaseous and elemental constituents. Effective filtration needs to be part of the suite of resource utilization technologies. A unique testing platform is being used which provides the relevant operational and instrumental capabilities to test articles under the proper simulated Martian conditions. A series of tests were conducted to assess the performance of filter media. Light sheet imaging of the particle flow provided a means of detecting and quantifying particle concentrations to determine capturing efficiencies. The media's efficiency was also evaluated by gravimetric means through a by-layer filter media configuration. These tests will help to establish techniques and methods for measuring capturing efficiency and arrestance of conventional fibrous filter media. This paper will describe initial test results on different filter media.

  16. Shoulder arthroplasty following gastric bypass, do complications follow? (United States)

    Schoch, Bradley S; Aibinder, William R; Werthel, Jean-David; Sperling, John W; Sanchez-Sotelo, Joaquin; Cofield, Robert H


    Previous reports have shown an increased risk of complications after arthroplasty in the obese population. It remains unclear if gastric bypass surgery prior to shoulder arthroplasty modifies the complication and failure rate. The purpose of this study is to assess the complication and re-operation rates following shoulder arthroplasty in this population. Between 2002 and 2012, 39 shoulders with prior gastric bypass underwent shoulder arthroplasty (3 HA, 16 TSA, 20 RSA). The mean time from the gastric bypass to arthroplasty was 13 years (range, 0.7-32). Shoulders were followed for a minimum of two years (mean, 3.8 years) or until re-operation. Outcome measures included pain, range of motion, satisfaction, modified Neer ratings, and ASES scores. Complications occurred in seven shoulders (18%), with five requiring re-operation. There was no common failure mechanism. Re-operations occurred for aseptic glenoid loosening, periprosthetic fracture, and unexplained pain. Those shoulders with complications were similar to those without in regard to age, sex, and BMI. Complications were more common following anatomic arthroplasty compared to reverse arthroplasty (5 vs 1, p = 0.06); however, complications were not improved compared to historical controls with morbid obesity. Overall, pain improved significantly from 4.8 pre-operatively to 2.3 postoperatively (p bypass surgery prior to shoulder arthroplasty leads to clinical improvement in both pain and range of motion. Prior gastric bypass surgery does not result in a lower surgical complication rate compared to previously published reports in the morbidly obese population. Level 4, case series.

  17. Cancer incidence and mortality after gastric bypass surgery. (United States)

    Adams, Ted D; Stroup, Antoinette M; Gress, Richard E; Adams, Kenneth F; Calle, Eugenia E; Smith, Sherman C; Halverson, R Chad; Simper, Steven C; Hopkins, Paul N; Hunt, Steven C


    Despite weight loss recommendations to prevent cancer, cancer outcome studies after intentional weight loss are limited. Recently, reduced cancer mortality following bariatric surgery has been reported. This study tested whether reduced cancer mortality following gastric bypass was due to decreased incidence. Cancer incidence and mortality data through 2007 from the Utah Cancer Registry (UCR) were compared between 6,596 Utah patients who had gastric bypass (1984-2002) and 9,442 severely obese persons who had applied for Utah Driver's Licenses (1984-2002). Study outcomes included incidence, case-fatality, and mortality for cancer by site and stage at diagnosis of all gastric bypass patients, compared to nonoperated severely obese controls. Follow-up was over a 24-year period (mean 12.5 years). Total cancer incidence was significantly lower in the surgical group compared to controls (hazard ratio (HR) = 0.76; confidence interval (CI) 95%, 0.65-0.89; P = 0.0006). Lower incidence in surgery patients vs. controls was primarily due to decreased incidence of cancer diagnosed at regional or distant stages. Cancer mortality was 46% lower in the surgery group compared to controls (HR = 0.54; CI 95%, 0.37-0.78; P = 0.001). Although the apparent protective effect of surgery on risk of developing cancer was limited to cancers likely known to be obesity related, the inverse association for mortality was seen for all cancers. Significant reduction in total cancer mortality in gastric bypass patients compared with severely obese controls was associated with decreased incidence, primarily among subjects with advanced cancers. These findings suggest gastric bypass results in lower cancer risk, presumably related to weight loss, supporting recommendations for reducing weight to lower cancer risk.

  18. Intraoperative Eptifibatide Administration During Urgent Arterial Bypass in Neurosurgery. (United States)

    Stambolija, Vasilije; Mrak, Goran; Lozic, Marin; Ljevak, Josip; Miklic Bublic, Martina; Scap, Miroslav


    In some cases when risk of occlusion of a blood vessel is greater than risk of bleeding when patients undergo urgent or unplanned bypass during neurosurgery, the use of eptifibatide may be an option. We describe 2 patients who underwent arterial bypass in whom eptifibatide was used successfully intraoperatively during neurosurgery for prevention of bypass occlusion. The first patient presented with a right middle cerebral artery (MCA) aneurysm with subocclusive stenosis of the M1 branch. After right-sided osteoplastic frontotemporal craniotomy, the MCA bifurcation was exposed with a bifurcational 6-mm aneurysm with a wide neck. Prebifurcation stenosis was found, with yellow calcification of the vessel wall, and postbifurcation calcification was found on the upper M2 branch. Superficial temporal artery-MCA bypass and occlusion of the MCA aneurysm was done. Before the bypass, continuous intravenous infusion of eptifibatide 1 μg/kg/minute was administered. The patient recovered normally without hemorrhage or neurologic deficit. The second patient presented with a left-sided lateral sphenoid wing meningioma. Left-sided frontotemporal craniotomy was performed, and the tumor was completely removed from the arachnoid layer. The temporal M3 branch was invaded by the meningioma. As there was no flow through the invaded segment of the aforementioned artery, termino-terminal M3 arterial anastomosis was done. Continuous intravenous infusion of eptifibatide 1 μg/kg/minute was administered. Indocyanine green angiography showed normal flow through the anastomosis, and the patient recovered normally. Future studies are needed to test the safety and potential efficacy of eptifibatide in intraoperative settings. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Validation of viscoelastic coagulation tests during cardiopulmonary bypass. (United States)

    Ortmann, E; Rubino, A; Altemimi, B; Collier, T; Besser, M W; Klein, A A


    Viscoelastic point-of-care tests such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM) are increasingly used to guide hemostatic therapy after cardiac surgery. The aim of this study was to assess their clinical utility during cardiopulmonary bypass to predict postbypass coagulation status and to guide therapy. In this prospective study, TEG and ROTEM tests were performed in 52 adult patients undergoing elective cardiac surgery at two time points: near the end of cardiopulmonary bypass and after heparin reversal with protamine. The 95% confidence intervals of the mean difference were compared with a prespecified clinically relevant limit of ± 20% of the value after protamine. Both viscoelastic fibrinogen assays were well within the prespecified clinically relevant limit (≥ 79% of patients). The laboratory Clauss fibrinogen was much lower during cardiopulmonary bypass than after protamine (mean difference 1.2 g L(-1) , 95% CI 1.03-1.4, which was outside a clinically acceptable difference. For intrinsically activated tests, clotting times (CT) were different and outside the prespecified limit on TEG (mean difference -1.2 min, 95% CI -1.8 to -0.6) but not on ROTEM (mean difference 2.3 sec, 95% CI -8.6 to 13.2), while clot strength was well within the clinical limit on both devices (≥ 94% of patients). For extrinsically activated tests, clot strength on both TEG and ROTEM was within the pre-specified limit in 98% of patients. Results from TEG and ROTEM tests performed toward the end of cardiopulmonary bypass are similar to results after reversal of heparin. Amplitudes indicating clot strength were the most stable parameters across all tests, whereas CT showed more variability. In contrast, laboratory testing of fibrinogen using the Clauss assay was essentially invalid during cardiopulmonary bypass. © 2015 International Society on Thrombosis and Haemostasis.

  20. Cold agglutinins in patients undergoing cardiac surgery requiring cardiopulmonary bypass. (United States)

    Barbara, David W; Mauermann, William J; Neal, James R; Abel, Martin D; Schaff, Hartzell V; Winters, Jeffrey L


    Cold agglutinins (CA) are circulating autoantibodies present in most humans. They are active below normal body temperatures. Cold hemagglutinin disease involves the presence of CA sufficiently active at temperatures in the periphery to produce hemolysis or agglutination. Systemic hypothermia and cold cardioplegia may result in agglutination or hemolysis. We reviewed the experience of a large referral center in managing patients with CA and cold hemagglutinin disease undergoing cardiac surgery requiring cardiopulmonary bypass. The electronic medical records from 2002 to 2010 were searched to identify patients with CA or cold hemagglutinin disease who underwent cardiac surgery requiring cardiopulmonary bypass. Information related to preoperative CA testing and treatment, surgery, cardiopulmonary bypass, postoperative complications, and mortality was recorded. Sixteen patients underwent 19 procedures requiring cardiopulmonary bypass. Six patients had cold hemagglutinin disease. The identification of CA was made intraoperatively in 3 patients. One patient underwent preoperative plasma exchange. Cold blood cardioplegia was used in 2 of 16 procedures using cardioplegia, with the remaining using warmer blood cardioplegia. The lowest recorded intraoperative core temperature was less than 34 °C in 1 case. CA-related postoperative hemolysis requiring transfusion was present in 1 patient, which was resolved with active warming. No patient had evidence of permanent myocardial dysfunction, had a neurologic event, required dialysis, or died within 30 days. All patients with CA/cold hemagglutinin disease at the Mayo Clinic College of Medicine safely underwent cardiac surgery without major adverse morbidity or mortality. Patients with CA but without evidence of cold hemagglutinin disease can safely undergo normothermic cardiopulmonary bypass at 37°C and warm cardioplegia without further testing. Patients with cold hemagglutinin disease should undergo laboratory testing including