Sample records for starr-edwards ball valve

  1. Structural valve deterioration in a starr-edwards mitral caged-disk valve prosthesis.

    PubMed

    Aoyagi, Shigeaki; Tayama, Kei-Ichiro; Okazaki, Teiji; Shintani, Yusuke; Kono, Michitaka; Wada, Kumiko; Kosuga, Ken-Ichi; Mori, Ryusuke; Tanaka, Hiroyuki

    2013-01-01

    The durability of the Starr-Edwards (SE) mitral caged-disk valve, model 6520, is not clearly known, and structural valve deterioration in the SE disk valve is very rare. Replacement of the SE mitral disk valve was performed in 7 patients 23-40 years after implantation. Macroscopic examination of the removed disk valves showed no structural abnormalities in 3 patients, in whom the disk valves were removed at <26 years after implantation. Localized disk wear was found at the sites where the disk abutted the struts of the cage, in disk valves excised >36 years after implantation in 4 patients. Disk fracture, a longitudinal split in the disk along its circumference at the site of incorporation of the titanium ring, was detected in the valves removed 36 and 40 years after implantation, respectively, and many cracks were also observed on the outflow aspect of the disk removed 40 years after implantation. Disk fracture and localized disk wear were found in the SE mitral disk valves implanted >36 years previously. The present results suggest that SE mitral caged-disk valves implanted >20 years previously should be carefully followed up, and that those implanted >30 years previously should be electively replaced with modern prosthetic valves

  2. Thirty-Seven-Year Durability of a Starr-Edwards Aortic Prosthesis

    PubMed Central

    Ozkokeli, Mehmet; Ates, Mehmet; Ekinci, Abdurrahman; Akcar, Murat

    2005-01-01

    We report the case of a patient who was diagnosed with prosthetic valve endocarditis caused by Staphylococcus aureus. He had undergone aortic valve replacement with a Starr-Edwards prosthesis 37 years earlier. Because of uncontrolled infection despite antibiotic treatment, the patient underwent successful surgical replacement of the prosthetic valve. PMID:15902834

  3. Ball valve extractor

    DOEpatents

    Herndon, Charles; Brown, Roger A.

    2002-01-01

    An apparatus and process for removing a ball valve is provided. The ball valve removal tool provides a handle sliding along the length of a shaft. One end of the shaft is secured within an interior cavity of a ball valve while the opposite end of the shaft defines a stop member. By providing a manual sliding force to the handle, the handle impacts the stop member and transmits the force to the ball valve. The direction of the force is along the shaft of the removal tool and disengages the ball valve from the ball valve housing.

  4. 17. DETAIL, FOURTEENINCH LIQUID OXYGEN BALL VALVE. Looking south southeast. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. DETAIL, FOURTEEN-INCH LIQUID OXYGEN BALL VALVE. Looking south southeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  5. 16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEENINCH BALL VALVE. Looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEEN-INCH BALL VALVE. Looking southwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  6. Stemless Ball Valve

    NASA Technical Reports Server (NTRS)

    Burgess, Robert K.; Yakos, David; Walthall, Bryan

    2012-01-01

    This invention utilizes a new method of opening and closing a ball valve. Instead of rotating the ball with a perpendicular stem (as is the case with standard ball valves), the ball is rotated around a fixed axis by two guide pins. This innovation eliminates the leak point that is present in all standard ball valves due to the penetration of an actuation stem through the valve body. The VOST (Venturi Off-Set-Technology) valve has been developed for commercial applications. The standard version of the valve consists of an off-set venturi flow path through the valve. This path is split at the narrowest portion of the venturi, allowing the section upstream from the venturi to be rotated. As this rotation takes place, the venturi becomes restricted as one face rotates with respect to the other, eventually closing off the flow path. A spring-loaded seal made of resilient material is embedded in the upstream face of the valve, making a leak-proof seal between the faces; thus a valve is formed. The spring-loaded lip seal is the only seal that can provide a class six, or bubble-tight, seal against the opposite face of the valve. Tearing action of the seal by high-velocity gas on this early design required relocation of the seal to the downstream face of the valve. In the stemless embodiment of this valve, inner and outer magnetic cartridges are employed to transfer mechanical torque from the outside of the valve to the inside without the use of a stem. This eliminates the leak path caused by the valve stems in standard valves because the stems penetrate through the bodies of these valves.

  7. Quartz ball valve

    NASA Technical Reports Server (NTRS)

    Goetz, C.; Ingle, W. M. (Inventor)

    1980-01-01

    A ball valve particularly suited for use in the handling of highly corrosive fluids is described. It is characterized by a valve housing formed of communicating segments of quartz tubing, a pair of communicating sockets disposed in coaxial alignment with selected segments of tubing for establishing a pair of inlet ports communicating with a common outlet port, a ball formed of quartz material supported for displacement between the sockets and configured to be received alternately thereby, and a valve actuator including a rod attached to the ball for selectively displacing the ball relative to each of the sockets for controlling fluid flow through the inlet ports.

  8. Results after mitral valve replacement with cloth-covered Starr-Edwards prostheses (models 6300, 6310/6320, and 6400).

    PubMed Central

    Forman, R; Beck, W; Barnard, C N

    1978-01-01

    The actuarial survival and thromboembolic rates for the three types of cloth-covered Starr-Edwards mitral prostheses, models 6300, 6310/6320, and 6400 followed 6, 5, and 2 years, respectively, were not significantly different throughout the years they were followed. The combined cumulative survival and thromboembolic proportion at 5 years for these prostheses were 71 and 66 per cent, respectively. The thromboembolic rates were not different in the following two groups: (a) 238 patients receiving anticoagulants, and (b) 52 patients who had discontinued or who were not receiving anticoagulants. Four patients thrombosed their mitral prostheses. Another 8 per cent had class 3 symptoms after operation, which were attributed to myopathic or restrictive left ventricular dysfunction or other valvular disease. PMID:656234

  9. Latching Solenoid-Operated Ball Valve

    NASA Technical Reports Server (NTRS)

    Brudnicki, Myron

    1994-01-01

    Proposed solenoid-operated ball valve latches in open or closed position until energized to change position. Electrical energy consumed only during opening or closing motion. Valve ball contains central channel through which fluid could flow. Made of highly magnetically permeable steel. When appropriate coil(s) energized by brief pulse (or pulses) of electrical current at appropriate polarity, ball rotates clockwise until permanent magnets come to rest against hard stops in housing, and inlet and outlet ports aligned with central channel so fluid flows through valve. Magnets adhere to stops by magnetic attraction, latching valve in open position. To close valve, appropriate coil(s) energized by pulse (or pulses) of appropriate polarity to generate magnetic forces rotating ball counterclockwise until magnets make contact with hard stops, and inlet and outlet ports sealed.

  10. Stemless ball valve

    NASA Technical Reports Server (NTRS)

    Burgess, Kevin (Inventor); Yakos, David (Inventor); Walthall, Bryan (Inventor)

    2011-01-01

    A stemless ball valve comprising two flanges and a ball with a channel, two axis pins and two travel pins. One end of each axis and travel pin is fixedly attached to the ball, and the other end of each axis pin is lodged into a notch in the first or second flange such that the axis pin is allowed to rotate in the notch. The guide sleeve comprises two channels, and one end of each travel pin is situated within one of the two channels in the guide sleeve. An outer magnetic cartridge causes the inner magnetic cartridge and guide sleeve to rotate, and when the guide sleeve rotates, the travel pins move up and down within the channels in the guide sleeve. The movement of the travel pins within the channels in the guide sleeve causes the ball to rotate, thereby opening and closing the ball valve.

  11. Stemless ball valve

    NASA Technical Reports Server (NTRS)

    Burgess, Kevin (Inventor); Yakos, David (Inventor); Walthall, Bryan (Inventor)

    2012-01-01

    A stemless ball valve comprising: a right flange; left flange; ball with an axis pin and two travel pins; ball seal on either side of the ball; guide sleeve with inner walls comprising two channels; cartridge guide holder; inner magnetic cartridge; and outer magnetic cartridge. The ball is situated inside of the guide sleeve, and a travel pin is located in each of the two channels. The guide sleeve is situated inside of the cartridge guide holder, which is located adjacent to and outside of the inner magnetic cartridge and secured to the inner magnetic cartridge such that when the inner magnetic cartridge rotates, the cartridge guide holder also rotates. The cartridge guide holder is secured to the guide sleeve such that when the cartridge guide holder rotates, the travel pins move within the channels in the inner walls of the guide sleeve, thereby causing the ball to rotate.

  12. Durability Tests of Ball Valve Prototype with Flowmeter Operation

    NASA Astrophysics Data System (ADS)

    Rogula, J.; Romanik, G.

    2018-02-01

    The results of the investigation of the prototypical ball valve are presented in this article. The innovation of the tested valve is a ball with a built-in measuring orifice. The valve has been subjected to durability tests. Leakage under three temperatures: ambient, -30°C and +100°C was analyzed. Sealing elements of the valve were tested for roughness and deviation of shape before and after the cycles of operation. Ball valve operation means cycles of open/close. It was planned to perform 1000 cycles at each temperature condition accordingly. Tests of the valve were performed under gas pressure equal to 10 MPa. The research was carried out under the Operational Program "Intelligent Development" (POIR 01.01.01-00-0013 / 15 "Development of devices for measurement of media flow on industrial trunk-lines".

  13. Whitey SCHe Ball Valves Provide Test Port Isolation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    MISKA, C.R.

    2000-09-15

    These valves are 1/4 inch ball valves fabricated of 316 stainless steel. Packing is TFE (standard). They are used as normally closed isolation valves for test ports in the SCHe System between the gage root valve and the pressure indicator.

  14. Space Shuttle Orbital Maneuvering Subsystem (OMS) Engine Propellant Leakage Ball-Valve Shaft Seals

    NASA Technical Reports Server (NTRS)

    Lueders, Kathy; Buntain, Nick; Fries, Joseph (Technical Monitor)

    1999-01-01

    Evidence of propellant leakage across ball-valve shaft seals has been noted during the disassembly of five flight engines and one test engine at the NASA Lyndon B. Johnson Space Center, White Sands Test Facility. Based on data collected during the disassembly of these five engines, the consequences of propellant leakage across the ball-valve shaft seals can be divided into four primary areas of concern: Damage to the ball-valve pinion shafts, damage to sleeved bearings inside the ball-valve and actuator assemblies, degradation of the synthetic rubber o-rings used in the actuator assemblies, and corrosion and degradation to the interior of the actuator assemblies. The exact time at which leakage across the ball-valve shaft seals occurs has not been determined, however, the leakage most likely occurs during engine firings when, depending on the specification used, ball-valve cavity pressures range as high as 453 to 550 psia. This potential pressure range for the ball-valve cavities greatly exceeds the acceptance leakage test pressure of 332 psia. Since redesign and replacement of the ball-valve shaft seals is unlikely, the near term solution to prevent damage that occurs from shaft-seal leakage is to implement a routine overhaul and maintenance program for engines in the fleet. Recommended repair, verification, and possible preventative maintenance measures are discussed in the paper.

  15. Transfemoral implantation of an Edwards SAPIEN valve in a tricuspid bioprosthesis without fluoroscopic landmarks.

    PubMed

    Calvert, Patrick A; Himbert, Dominique; Brochet, Eric; Radu, Costin; Iung, Bernard; Hvass, Ulrik; Darondel, Jean-Marc; Depoix, Jean-Pol; Nataf, Patrick; Vahanian, Alec

    2012-03-01

    We describe the first report of an Edwards SAPIEN valve implanted in a tricuspid bioprosthesis from the femoral vein. We highlight the feasibility of this previously avoided approach and the techniques involved. A 61-year-old woman with multiple valve replacements for rheumatic heart disease presented with NHYA IV dyspnoea secondary to a severely stenosed tricuspid bioprosthesis. After failed aggressive medical therapy and surgical turn down, an Edwards SAPIEN XT valve was deployed in the tricuspid bioprosthesis via the right femoral vein. Adaptations to the standard transfemoral transcatheter aortic valve implantation (TAVI) technique included: (1) crossing the tricuspid bioprosthesis with a balloon floatation catheter; (2) temporary pacing wire in the coronary sinus rather than the right ventricle; (3) mounting of the SAPIEN XT valve in the reverse orientation to transfemoral TAVI; and (4) fine positioning of the final valve position pre-deployment by 3D transoesophageal echocardiography (3D TOE) alone due to complete radiolucency of the tricuspid bioprosthesis. The procedure was completed without complication and resulted in significant symptomatic improvement. Deployment of an Edwards SAPIEN valve in a tricuspid bioprosthesis via the femoral vein is feasible and, with careful adaptations to established TAVI techniques, can be performed without complications and with good clinical response.

  16. Long-term results of heart valve replacement with the Edwards Duromedics bileaflet prosthesis: a prospective ten-year clinical follow-up.

    PubMed

    Podesser, B K; Khuenl-Brady, G; Eigenbauer, E; Roedler, S; Schmiedberger, A; Wolner, E; Moritz, A

    1998-05-01

    The Edwards Duromedics valve (Baxter Healthcare Corp., Edwards Division, Santa Ana, Calif.) was designed with a self-irrigating hinge mechanism to reduce thromboembolic complications. After good initial clinical results, distribution was suspended in 1988 after reports of valve fracture after 20,000 valves had been implanted. The manufacturer conducted extensive studies to improve the Edwards Duromedics and reintroduced a modified version, which is available as Edwards Tekna. The purpose of the study was the evaluation of long-term results of the original Edwards Duromedics that might be important for the current version, the Edwards Tekna valve. A prospective clinical 10-year follow-up was performed of 508 patients who underwent valve replacement with the Edwards Duromedics valve in the aortic (n = 268), mitral (n = 183), and aortic and mitral (n = 56) position. The perioperative mortality rate was 6.9%; follow-up was 98% complete, comprising 3648 patient-years for a mean follow-up of 86 months (range: 33 to 144 months). The actuarial freedom from complications at the 10-year follow-up and the incidence rate (percent per patient-year) were as follows: late mortality rate, 69.2% +/- 2.4% (3.5% per patient-year); thromboembolism, 90.7% +/- 1.6% (0.96% per patient-year); anticoagulation-related hemorrhage, 87.7% +/- 1.7% (1.34% per patient-year); prosthetic valve endocarditis, 96.7% +/- 0.09% (0.38% per patient-year); valve-related mortality rate, 89.3% +/- 1.6% (1.21% per patient-year); valve failure, 86.2% +/- 1.85% (1.54% per patient-year); and valve-related morbidity and mortality rate, 71.1% +/- 2.3% (3.2% per patient-year). Three leaflet escapes were observed (one lethal, two successful reoperations; 99.1% +/- 0.05% freedom, 0.08% per patient-year). All patients functionally improved (86% in New York Heart Association classes I and II), and incidence of anemia was insignificant. These results confirm that the Edwards Duromedics valve shows excellent performance

  17. Mitral valve pericardioplasty—a long-term follow-up study

    PubMed Central

    Van Der Spuy, J. C.

    1972-01-01

    Posterior (17) and anterior (3) mitral cusp pericardioplasties were performed in 20 patients between 6 December 1961 and 10 July 1963. A long-term follow-up study was done in nine patients. In six of these, mitral valvectomy with Starr-Edwards ball valve replacement was required after intervals varying between two years and three months and seven years and three months. In only one of the six cases did the pericardium macroscopically appear normal. In four it was obviously thickened and in two of the four there was also evidence of calcification in the pericardium only. In one of these, calcification was gross, causing complete immobility of the whole 2 × 0·6 in (5 × 1·7 cm) pericardial inlay. In only one of the six cases had the pericardium become larger and thinner and this also was in the only patient with a dilated mitral ring. Only three patients remain with the pericardium as inserted into the posterior mitral cusp between eight years and eight years and eleven months previously, but in all three there is clinical evidence of progressive pathology in the mitral valve. The progressive mitral valve involvement in this series could well have been caused by progression of the pre-existing pathology in the cusps and chordae tendineae but the involvement of the pericardial inlay was much more extensive than that of the rest of the cusp. Images PMID:5034597

  18. Valve-in-valve using an Edwards Sapien XT into a JenaValve in a patient with a low originating left coronary artery and a heavily calcified aorta.

    PubMed

    Fujita, Buntaro; Scholtz, Smita; Ensminger, Stephan

    2016-04-01

    Coronary obstruction during transcatheter aortic valve implantation is a potentially life-threatening complication. Most of the widely used transcatheter heart valves require a certain distance between the basal aortic annular plane and the origins of the coronary arteries. We report the case of a successful valve-in-valve procedure with an Edwards SAPIEN XT valve into a JenaValve as a bail-out procedure in a patient with a low originating left coronary artery and a heavily calcified aorta. © 2015 Wiley Periodicals, Inc.

  19. Mitral valve replacement with preservation of the subvalvular apparatus.

    PubMed

    Reardon, M J; David, T E

    1999-03-01

    The introduction of the Starr-Edwards valve allowed complete replacement of diseased left-sided heart valves. With improved cardiopulmonary bypass, myocardial protection, and surgical techniques the mortality rate from aortic valve replacement decreased substantially, whereas the mortality rate from mitral valve replacement remained high, largely because of low cardiac output syndrome. Increasing use of mitral valve repair techniques resulted in a marked decrease in short-term and long-term morbidity and mortality when treating patients with mitral regurgitation. Some believed that this resulted from maintenance of the mitral annular papillary muscle continuity during mitral valve repair. Subsequent experimental and clinical studies have validated the positive short-term and long-term effects of maintaining the integrity of the mitral valve subvalvular apparatus. This article considers the history of the clinical use of preservation of the subvalvular apparatus, the physiologic studies examining this concept, and the clinical data available on its use. It also examines the following: 1) mitral stenosis versus mitral regurgitation and the preservation of the subvalvular apparatus; 2) whether the anterior, posterior, or both areas of the subvalvular apparatus should be preserved; and 3) the surgical techniques for the preservation of the subvalvular apparatus and valve implantation.

  20. [Phonomechanocardiography in the evaluation of the functional status of valvular prosthesis].

    PubMed

    Esquivel Avila, J; Molina Zapata, B; Martínez Ríos, M A; Flamand, E

    1975-01-01

    The FMCG in 22 patients with valvular prosthesis is analyzed and its clinical, hemodynamic and surgical correlation are established (11 from the I.N.C. and 11 from the Hospital Infantil I.M.A.N.). The average age of the patients was 15 years old, 18 had a mitral and six aortic valvulopathy, and they all required a valvular replacement. Of the mitral prosthesis, 14 were Starr-Edwards (13 of ball valve and one of disc), three Lillehei-Kaster and one Börck-Shiley. In 5 patients, the FMCG suspected disfunction that was later corroborated by catheterism in three patients and by surgery in all of them. The important differences of the FMCG between the group with good and the one with bad function were: the aparition of a rumble, a decrease in the amplitud of the closing snap, index of closing snap opering snap of less than one, lenghtening of fases PFVP and IVCP, and shortening of IVDRP. In the patients with auricular fibrilation, after long dyastoles; that would represent an adequate atrial emptying; the closing snap was more intense, the PFVP was lennthened the IVDRP was shortened when the prosthesis was not properly functioning. All the aortic prosthesis were ball valve Starr-Edwards type; in one the FMCG suspected disfunction and the patient had a sudden death outside of the Hospital. The significant differences of the FMCG were the decrease in the intensity of the opening snap, with a Hylen index of less than one, lengthening of the PFVP, IVCP and of the expulsive period (EP). The authors conclude that the FMCG is a good method for an early detection of the disfunctions of valvular prosthesis.

  1. Pannus overgrowth after mitral valve replacement with a Carpentier-Edwards pericardial bioprosthesis.

    PubMed

    Oda, Takeshi; Kato, Seiya; Tayama, Eiki; Fukunaga, Shuji; Akashi, Hidetoshi; Aoyagi, Shigeaki

    2009-01-01

    A Carpentier-Edwards pericardial (CEP) bioprosthesis was explanted from an 81-year-old woman due to nonstructural dysfunction 9 years after mitral valve replacement. The nonstructural dysfunction produced severe regurgitation in the mitral position. During the surgery, excessive pannus overgrowth was seen on the left ventricular side of the CEP bioprosthesis. Pannus overgrowth was prominent on one leaflet. That leaflet was stiff and shortened due to the excessive overgrowth of pannus. In this patient, the distortion of one leaflet was the main reason for transvalvular leakage of the CEP bioprosthesis in the mitral position. A new CEP bioprosthesis was implanted in the mitral position. Pathological analysis revealed fibrotic pannus with a small amount of cellular material over the leaflets of the resected CEP valve. This change was marked on the distorted leaflet.

  2. Transapical aortic valve implantation in Rouen: four years' experience with the Edwards transcatheter prosthesis.

    PubMed

    Litzler, Pierre-Yves; Borz, Bogdan; Smail, Hassiba; Baste, Jean-Marc; Nafeh-Bizet, Catherine; Gay, Arnaud; Tron, Christophe; Godin, Matthieu; Caudron, Jerome; Hauville, Camille; Dacher, Jean-Nicolas; Cribier, Alain; Eltchaninoff, Hélène; Bessou, Jean-Paul

    2012-03-01

    The first French transapical transcatheter aortic valve implantation (TAVI) was performed in July 2007 in our department. To report 4-year outcomes of transapical implantation with the Edwards transcatheter bioprosthesis. We prospectively evaluated consecutive patients who underwent transapical implantation with an Edwards transcatheter bioprosthesis between July 2007 and October 2011. Patients were not suitable for conventional surgery (due to severe comorbidities) or transfemoral implantation (due to poor femoral access). Among 61 patients (59.0% men), mean logistic EuroSCORE was 27.5 ± 14.9% and mean age was 81.0 ± 6.8 years. Successful valve implantation was achieved in 59/61 patients (96.7%) of patients. The other two patients required conversion to conventional surgery due to prosthesis embolization and died. Six additional patients died in the postoperative period. Causes of perioperative death were two septic shocks (one of peritonitis), two multi-organ failure, one ventricular fibrillation and one respiratory insufficiency. Intraprocedural stroke was not observed in any patient. The actuarial survival rates at 1, 2 and 4 years were 73.8%, 67.2% and 41.0%. During this 4-year period, four patients died of cardiovascular events, but no impairment of transprosthesis gradient was observed. Our series of 61 patients who underwent transapical implantation of the Edwards transcatheter bioprosthesis shows satisfactory results, similar to other reports, considering the high level of severity of patients referred for this method. Transapical access is a reliable alternative method for patients that cannot benefit from a transfemoral approach. Copyright © 2012. Published by Elsevier Masson SAS.

  3. Late outcomes for aortic valve replacement with the Carpentier-Edwards pericardial bioprosthesis: up to 17-year follow-up in 1,000 patients.

    PubMed

    McClure, R Scott; Narayanasamy, Narendren; Wiegerinck, Esther; Lipsitz, Stuart; Maloney, Ann; Byrne, John G; Aranki, Sary F; Couper, Gregory S; Cohn, Lawrence H

    2010-05-01

    This study reviews a single institution experience with the Carpentier-Edwards pericardial aortic valve bioprosthesis, concentrating on late outcomes. From December 1991 to June 2002, 1,000 patients underwent aortic valve replacement with the Carpentier-Edwards pericardial valve (mean follow-up 6.01 +/- 3.56 years). The institutional database was reviewed. Follow-up data were acquired through telephone interviews and mail-in questionnaires. Time-to-event analyses were performed by the Kaplan-Meier method. Mean age was 74.1 years; 545 patients (54.5%) were male. Mean preoperative ejection fraction was 52.5%. Isolated aortic valve replacement occurred in 372 cases (37.2%). Combined aortic valve replacement with coronary artery bypass grafting occurred in 443 cases (44.3%). The remaining 185 patients (18.5%) underwent complex procedures with concomitant mitral, tricuspid, or arch repair. One hundred forty patients (14.0%) had prior aortic valve surgery. Follow-up was 99.4% complete. Overall operative mortality was 7.2% (72 of 1,000). There were 503 late deaths (50.3%). Age-stratified survival at 15 years was 43.7% for patients less than 65 years of age; 18.2% for patients aged 65 to 75; and 9.4% for patients aged more than 75 years. There were 26 failed bioprostheses (2.6%) requiring reoperation. Structural valve deterioration was the cause in 13 of 26 cases (50%), endocarditis in 11 of 26 (42%), and perivalvular leak in 2 of 26 (7.6%). Age-stratified freedom from reoperation due to structural valve deterioration at 15 years was 34.7% for patients less than 65 years of age; 89.4% for patients aged 65 to 75; and 99.5% for patients aged more than 75 years. The Carpentier-Edwards pericardial bioprosthesis shows long-term durability with low rates of structural failure. Copyright (c) 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  4. [Extracorporeal ventriculoatrial shunt with the use of one-way ball valve].

    PubMed

    Kubo, Shigeki; Takimoto, Hiroshi; Hosoi, Kazuki; Toyota, Shingo; Takakura, Shuji; Hayashi, Yasuhiro; Ueno, Masato; Morisako, Toshitaka; Karasawa, Jun; Ninaga, Hideo; Yoshimine, Toshiki

    2002-04-01

    We developed a simple system of an "extracorporeal" ventriculoatrial (VA) shunt using a one-way ball valve (Acty valve II, Kaneka Medix) to release the patient from postoperative constraint during the ventricular drainage. The system is constructed in such a way that the ventricular drainage tube is connected to the central venous catheter via a one-way valve. The CSF is regulated by using the valve and is diverted into the systemic circulation as in the conventional ventriculoatrial shunt. After 2 or 3 weeks of CSF diversion through the extracorporeal VA shunt, a ventriculoperitoneal shunt is placed if hydrocephalus is apparent by temporary occlusion of the system. We applied this system to 4 patients with hydrocephalus, and we found it useful and free from adverse effects. The patient was freed from physical constraint involved in conventional ventricular drainage and an effective program of early rehabilitation was able to be started.

  5. Validation of continuous-wave Doppler echocardiographic measurements of mitral and tricuspid prosthetic valve gradients: a simultaneous Doppler-catheter study.

    PubMed

    Wilkins, G T; Gillam, L D; Kritzer, G L; Levine, R A; Palacios, I F; Weyman, A E

    1986-10-01

    For patients with stenotic native valves, the modified Bernoulli equation (delta P = 4V2) may be applied to Doppler-measured transvalvular velocities to yield an accurate estimate of transvalvular gradients. Although it would be useful if the same approach could be used for those with stenotic prosthetic valves, no previous study has validated the Doppler technique in this setting. We therefore recorded simultaneous continuous-wave Doppler flow profiles and transvalvular manometric gradients in 12 catheterized patients in whom all atrial and ventricular pressures were directly measured (transseptal left atrial catheterization and transthoracic ventricular puncture were performed where necessary). A total of 13 prostheses were studied: 11 mitral (seven porcine, three Starr-Edwards, and one Björk-Shiley) and two tricuspid (one porcine and one Björk-Shiley). The Doppler-determined mean gradient was calculated as the mean of the instantaneous gradients (delta P = 4V2) at 10 msec intervals throughout diastole. The correlation of simultaneous Doppler (DMG) and manometric mean gradients (MG) for the whole group (n = 13) demonstrated a highly significant relationship (MG = 1.07 DMG + 0.28; r = .96, p = .0001). The correlation was equally good for porcine valves alone (n = 8) (MG = 1.06 DMG + 0.55; r = .96, p = .001) and for mechanical valves alone (n = 5) (MG = 1.06 DMG - 0.04; r = .93, p = .02). In a subset of patients without regurgitation (n = 8), prosthetic valve areas were estimated by two Doppler methods originally described by Holen and Hatle, as well as by the invasive Gorlin method. As expected from theoretical considerations, a close correlation was not demonstrated between results of the Gorlin method and those of either Hatle's Doppler method (r = .65, fp = NS) or Holen's method (r = .14, p = NS). Comparison of the results of the two Doppler methods yielded a somewhat closer correlation (r = .73, p less than or equal to .05). These results suggest that in

  6. Early outcomes of percutaneous pulmonary valve implantation using the Edwards SAPIEN XT transcatheter heart valve system.

    PubMed

    Haas, Nikolaus A; Carere, Ronald Giacomo; Kretschmar, Oliver; Horlick, Eric; Rodés-Cabau, Josep; de Wolf, Daniël; Gewillig, Marc; Mullen, Michael; Lehner, Anja; Deutsch, Cornelia; Bramlage, Peter; Ewert, Peter

    2018-01-01

    Patients with congenital or acquired heart defects affecting the pulmonary valve and right ventricular outflow tract (RVOT) commonly require multiple surgical interventions, resulting in significant morbidity. A less invasive alternative is percutaneous pulmonary valve implantation (PPVI). Though studies have previously reported the safety and efficacy of the early generation transcatheter heart valves (THVs), data on more recent devices are severely lacking. We performed a multinational, multicentre, retrospective, observational registry analysis of patients who underwent PPVI using the Edwards SAPIEN XT THV. Of the 46 patients that were enrolled, the majority had tetralogy of Fallot as the underlying diagnosis (58.7%), and stentless xenograft as the most common RVOT anatomy (34.8%). Procedural success rate was high (93.5%), with a low frequency of periprocedural complications and adverse events (6.5% and 10.9%, respectively). At 30days post-procedure, NYHA class had improved significantly (90.6% were at NYHA I or II). The rate of moderate/severe pulmonary regurgitation had decreased from 76.1% at baseline to 5.0% at 30days, and the calculated peak systolic gradient had decreased from 45.2 (SD±21.3) mmHg to 16.4 (SD±8.0) mmHg, with these values remaining low up to 2years. The data suggest the efficacy and safety of the SAPIEN XT THV in PPVI in common anatomies in patients with conduits, as well as those with native pulmonary valves or transannular patches. Continued data collection is necessary to verify long-term findings. CLINICALTRIALS. NCT02302131. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Short- and long-term need for permanent pacemaker after transcatheter implantation of the Edwards Sapien aortic valve prosthesis.

    PubMed

    Moreno, Raúl; Calvo, Luis; Sánchez-Recalde, Angel; Galeote, Guillermo; Jiménez-Valero, Santiago; López, Teresa; Plaza, Ignacio; González-Davia, Rosa; Ramírez, Ulises; Mesa, Jose Maria; Moreno-Gomez, Isidro; López-Sendón, José-Luis

    2015-11-01

    A permanent pacemaker is frequently needed after transcatheter aortic valve implantation, but the available data are mainly on the CoreValve system. To evaluate the need for new permanent pacemaker after implantation of the Edwards Sapien device, as well as related factors. We included the first 100 patients treated with the Edwards Sapien device at our institution. Of these, 12 had a permanent pacemaker before the procedure, and thus our study population was the remaining 88 patients. A permanent pacemaker was indicated in eight patients (9.1%) during hospitalization or at 30 days. After discharge, another four patients needed a pacemaker (at 42 days and three, 18, and 30 months). Two variables were associated with the need for pacemaker during hospitalization: previous dialysis (13% vs. 1%, p=0.042) and complete right bundle branch block before the procedure (25% vs. 5%, p=0.032). More than one month after the procedure, the characteristics associated with the need for pacemaker were plasma creatinine level (2.5±1.7 vs. 1.3±0.6 mg/dl, p=0.001) and previous myocardial infarction (50% vs. 10%, p=0.013). The rate of pacemaker implantation with the Edwards Sapien device was 9.1%. Right bundle branch block and dialysis were associated with this complication.

  8. A Lifting Ball Valve for cryogenic fluid applications

    NASA Astrophysics Data System (ADS)

    Cardin, Joseph M.; Reinicke, Robert H.; Bruneau, Stephen D.

    1993-11-01

    Marotta Scientific Controls, Inc. has designed a Lifting Ball Valve (LBV) capable of both flow modulation and tight shutoff for cryogenic and other applications. The LBV features a thin-walled visor valving element that lifts off the seal with near axial motion before rotating completely out of the flow path. This is accomplished with a simple, robust mechanism that minimizes cost and weight. Conventional spherical rotating seats ar plagued by leakage due to 'scuffing' as the seal and seat slide against one another while opening. Cryogenic valves, which typically utilize plastic seals, are particularly susceptible to this type of damage. The seat in the LBV lifts off the seal without 'scuffing' making it immune to this failure mode. In addition, the LBV lifting mechanism is capable of applying the very high seating loads required to seal at cryogenic temperatures. These features make the LBV ideally suited for cryogenic valve applications. Another major feature of the LBV is the fact that the visor rotates completely out of the flow path. This allows for a smaller, lighter valve for a given flow capacity, especially for line sizes above one inch. The LBV is operated by a highly integrated 'wetted' DC brushless motor. The motor rotor is 'wetted' ion that it is immersed in the fluid. To ensure compatibility, the motor rotor is encased in a thin-walled CRES weldment. The motor stator is outside the fluid containment weldment and therefore is not in direct contact with the fluid. To preclude the potential for external leakage there are no static or dynamic seals or bellows across the pressure boundary. The power required to do the work of operating the valving mechanism is transmitted across the pressure boundary by electromagnetic interaction between the motor rotor and the stator. Commutation of the motor is accomplished using the output of a special 'wetted' resolver. This paper describes the design, operation, and element testing of the LBV.

  9. Commercial versus PARTNER study experience with the transfemoral Edwards SAPIEN valve for inoperable patients with severe aortic stenosis.

    PubMed

    Pendyala, Lakshmana K; Minha, Sa'ar; Barbash, Israel M; Torguson, Rebecca; Magalhaes, Marco A; Okubagzi, Petros; Loh, Joshua P; Chen, Fang; Satler, Lowell F; Pichard, Augusto D; Waksman, Ron

    2014-01-15

    In patients with aortic stenosis who cannot have surgery, transcatheter aortic valve replacement using the Edwards SAPIEN valve has been shown to improve survival rate and is approved for commercial use in the United States. This study aims to assess the clinical profile, procedural characteristics, and in-hospital complications in patients treated with a commercial SAPIEN valve outside the clinical trial context. We retrospectively analyzed 69 consecutive patients who underwent transcatheter aortic valve replacement with a commercial SAPIEN valve compared with 55 Placement of AoRTic traNscathetER valves (PARTNER) trial patients from cohort B enrolled in the same institution by the same Heart Team. Compared with the commercial group, patients in the PARTNER cohort B had higher mean Society of Thoracic Surgeons score (10 ± 5 vs 9 ± 4, p = 0.04) and a lower rate of peripheral arterial disease (19% vs 44%, p = 0.004). Most patients in the commercial group had the procedure under conscious sedation (83% vs 66%, p = 0.03). Planned surgical cut down for vascular access was rare in the commercial group (1.4% vs 46%, p <0.001). The overall rates of major vascular complications, life-threatening or major bleeding, and blood transfusions were lower in commercial group (7.2% vs 27%, p = 0.003; 2.9% vs 16%, p = 0.01; and 28% vs 60%, p <0.001, respectively). In-hospital all-cause mortality (5.8% vs 9.1%, p = 0.51) and stroke rates (7.2% vs 14.5%, p = 0.19) were not statistically different between groups. The median length of hospitalization (p <0.001) and postprocedural length of stay (p = 0.01) was shorter in the commercial group. In conclusion, transfemoral commercial use of the Edwards SAPIEN valve for inoperable patients shows similar in-hospital mortality and stroke rates compared with PARTNER cohort B. The refinements in the procedure such as more conscious sedation, experience of the operators, and careful vascular planning in the commercial group led to lesser

  10. ULTRA HIGH VACUUM VALVE

    DOEpatents

    Fry, W.A.

    1962-05-29

    A valve for high vacuum applications such as the CStellarator where chamber pressures as low as 2 x 10/sup -10/ mm Hg are necessary is designed with a line-of-sight path through the valve for visual inspection of the contents of reactants in such chambers. The valve comprises a turnable resilient metal ball having an aperture therethrough, means for selectively turning the ball to rotate the axis of its line-of-sight path, and soft, deformable opposing orifices that are movable relatively toward said ball to seal with opposite ball surfaces upon said movement of said axis of said line-of-sight path. The valve also includes a bellows seal connected between said orifices and internal actuating means that eliminates the requirement for gasketed turnable valve closing stems. (AEC)

  11. Conical Seat Shut-Off Valve

    NASA Technical Reports Server (NTRS)

    Farner, Bruce

    2013-01-01

    A moveable valve for controlling flow of a pressurized working fluid was designed. This valve consists of a hollow, moveable floating piston pressed against a stationary solid seat, and can use the working fluid to seal the valve. This open/closed, novel valve is able to use metal-to-metal seats, without requiring seat sliding action; therefore there are no associated damaging effects. During use, existing standard high-pressure ball valve seats tend to become damaged during rotation of the ball. Additionally, forces acting on the ball and stem create large amounts of friction. The combination of these effects can lead to system failure. In an attempt to reduce damaging effects and seat failures, soft seats in the ball valve have been eliminated; however, the sliding action of the ball across the highly loaded seat still tends to scratch the seat, causing failure. Also, in order to operate, ball valves require the use of large actuators. Positioning the metal-to-metal seats requires more loading, which tends to increase the size of the required actuator, and can also lead to other failures in other areas such as the stem and bearing mechanisms, thus increasing cost and maintenance. This novel non-sliding seat surface valve allows metal-to-metal seats without the damaging effects that can lead to failure, and enables large seating forces without damaging the valve. Additionally, this valve design, even when used with large, high-pressure applications, does not require large conventional valve actuators and the valve stem itself is eliminated. Actuation is achieved with the use of a small, simple solenoid valve. This design also eliminates the need for many seals used with existing ball valve and globe valve designs, which commonly cause failure, too. This, coupled with the elimination of the valve stem and conventional valve actuator, improves valve reliability and seat life. Other mechanical liftoff seats have been designed; however, they have only resulted in

  12. IOTA: the array controller for a gigapixel OTCCD camera for Pan-STARRS

    NASA Astrophysics Data System (ADS)

    Onaka, Peter; Tonry, John; Luppino, Gerard; Lockhart, Charles; Lee, Aaron; Ching, Gregory; Isani, Sidik; Uyeshiro, Robin

    2004-09-01

    The PanSTARRS project has undertaken an ambitious effort to develop a completely new array controller architecture that is fundamentally driven by the large 1gigapixel, low noise, high speed OTCCD mosaic requirements as well as the size, power and weight restrictions of the PanSTARRS telescope. The result is a very small form factor next generation controller scalar building block with 1 Gigabit Ethernet interfaces that will be assembled into a system that will readout 512 outputs at ~1 Megapixel sample rates on each output. The paper will also discuss critical technology and fabrication techniques such as greater than 1MHz analog to digital converters (ADCs), multiple fast sampling and digital calculation of multiple correlated samples (DMCS), ball grid array (BGA) packaged circuits, LINUX running on embedded field programmable gate arrays (FPGAs) with hard core microprocessors for the prototype currently being developed.

  13. Electro-Mechanical Coaxial Valve

    NASA Technical Reports Server (NTRS)

    Patterson, Paul R (Inventor)

    2004-01-01

    Coaxial valves usually contain only one moving part. It has not been easy, then, to provide for electric motor actuation. Many actuators being proposed involve designs which lead to bulky packages. The key facing those improving coaxial valves is the provision of suitable linear actuation. The valve herein indudes a valve housing with a flow channel there-through. Arranged in the flow channel is a closing body. In alignment with the closing body is a ball screw actuator which includes a ball nut and a cylindrical screw. The ball nut sounds a threaded portion of the cylindrical screw. The cylindrical screw is provided with a passageway there-through through which fluid flows. The cylindrical screw is disposed in the flow channel to become a control tube adapted to move toward and away from the valve seat. To rotate the ball nut an actuating drive is employed driven by a stepper motor.

  14. The effect of X-ray beam distortion on the Edwards Sapien XT(™) trans-catheter aortic valve replacement prosthesis.

    PubMed

    Crowhurst, James A; Poon, Karl K; Murdoch, Dale; Incani, Alexander; Raffel, Owen C; Liddicoat, Annelise; Walters, Darren

    2015-12-01

    Profiling the Aortic root perpendicular to the fluoroscopic image plane will achieve a more successful implant position for trans-catheter aortic valve replacement (TAVR). This study aimed to investigate whether the divergent nature of the X-ray beam from the C-arm altered the appearance of the TAVR device. Under bench-top testing, a 23, 26 and 29 mm Edwards Sapien XT valve was positioned coaxially at the bottom of a fluoroscopic image utilising 22 and 32 cm fields of view (FOV). The table was then moved so that the valve was positioned at the top of the image. The valve's appearance was scored using a previously published three tier classification tool (excellent, satisfactory and poor) and quantified with measurements. The number of degrees of C-arm rotation that were required to bring the valve back to a coaxial appearance was recorded. When using the 32 cm FOV, the valve's appearance changes from excellent to satisfactory. When a 22 cm FOV was used, the change is less marked. More C-arm rotation is required to bring the appearance back to coaxial with the 32 cm FOV. Not maintaining the valve in the centre of the image can distort the valves appearance. This has the potential to affect the final implantation depth.

  15. Fast closing valve

    DOEpatents

    Hanson, Clark L.

    1984-01-10

    A valve is provided for protecting the high vacuum of a particle accelera in the event of air leakage, wherein the valve provides an axially symmetrical passage to avoid disturbance of the partical beam during normal operation, and yet enables very rapid and tight closure of the beam-carrying pipe in the event of air leakage. The valve includes a ball member (30) which can rotate between a first position wherein a bore (32) in the member is aligned with the beam pipe, and a second position out of line with the pipe. A seal member (38) is flexibly sealed to the pipe, and has a seal end which can move tightly against the ball member after the bore has rotated out of line with the pipe, to thereby assure that the seal member does not retard rapid rotation of the ball valve member. The ball valve member can be rapidly rotated by a conductive arm (40) fixed to it and which is rotated by the discharge of a capacitor bank through coils (44, 45) located adjacent to the arm.

  16. Excessive strut wear allowing ball-poppet embolization in a DeBakey-Surgitool aortic valve prosthesis.

    PubMed

    Sutherland, R D; Guynes, W A; Nichols, C T; Martinez, H E

    1982-01-01

    Excessive cage strut wear allowing ball-poppet embolization caused the sudden death of a 47 year old lady in whom a DeBakey-Surgitool aortic prosthesis had been implanted nine years earlier. Patients with this type of prosthesis should have periodic valvular cine fluoroscopy with image intensification to allow visualization of significant strut wear or fracture, and appropriate prosthetic valve replacement.

  17. Direct Comparison of the Edwards Intuity Elite and Sorin Perceval S Rapid Deployment Aortic Valves.

    PubMed

    Liakopoulos, Oliver J; Gerfer, Stephen; Weider, Simone; Rahmanian, Parwis; Zeriouh, Mohamed; Eghbalzadeh, Kaveh; Sabashnikov, Anton; Choi, Yeong-Hoon; Wippermann, Jens; Wahlers, Thorsten

    2018-01-01

    Rapid deployment aortic valve replacement (RDAVR) has emerged as an attractive alternative to conventional aortic valve replacement. This single-center study directly compared two commercially available rapid deployment valves with regard to clinical outcomes, valve-related complications, and hemodynamic performance. A total of consecutive 156 patients underwent RDAVR with the Intuity Elite (Edwards Lifesciences, Irvine, CA [Intuity group, n = 117] or the Perceval S (Sorin Group Italia Srl, Saluggia, Italy [Perceval group, n = 39]) between September 2012 and March 2016 at our institution. Perioperative data, including 30-day all-cause mortality, and echocardiographic measurements were assessed and retrospectively analyzed from our institutional database. Preoperative variables, including mean age (77 ± 5 years), European System for Cardiac Operative Risk Evaluation (6.8 ± 2.1), and body mass index (27 ± 5 kg/m 2 ), did not differ between groups. More male patients (60% versus 15%) with a higher body surface area (1.9 ± 0.2 m 2 versus 1.7 ± 0.2 m 2 ) and body weight (78 ± 13 kg versus 71 ± 15 kg) were in the Intuity group compared with the Perceval group, respectively (p < 0.05). Implanted RDAVR size (23.3 ± 1.8 mm versus 23.4 ± 1.5 mm), concomitant coronary artery bypass graft surgery (48% versus 33%), number of grafts, cardiopulmonary bypass, and aortic clamp time were comparable between the Intuity group and the Perceval group. Thirty-day mortality (Intuity 2.6% versus Perceval 5.1%) and valve-related complications (Intuity 12.0% versus Perceval 20.5%), including postoperative pacemaker implantation (Intuity 8.5% versus Perceval 12.8%), did not differ between groups. At discharge echocardiography, indexed effective orifice area was higher in the Intuity group, but peak or mean pressure gradients were comparable between groups. Performing RDAVR with the Intuity and Perceval rapid deployment valves provides comparable good clinical outcomes and valve

  18. Bioprosthetic mitral valve replacement in patients aged 65 years or younger: long-term outcomes with the Carpentier-Edwards PERIMOUNT pericardial valve.

    PubMed

    Bourguignon, Thierry; Espitalier, Fabien; Pantaleon, Clémence; Vermes, Emmanuelle; El-Arid, Jean Marc; Loardi, Claudia; Karam, Elias; Candolfi, Pascal; Ivanes, Fabrice; Aupart, Michel

    2018-02-12

    Mitral valve replacement using a bioprosthesis remains controversial in young patients because data on long-term outcomes are missing. This study evaluated the long-term results of the PERIMOUNT pericardial mitral bioprosthesis in patients aged 65 years or younger. From 1984 to 2010, 148 Carpentier-Edwards PERIMOUNT mitral bioprostheses were implanted in 148 patients aged 65 years or younger. Baseline clinical, perioperative and follow-up data were recorded prospectively. Structural valve deterioration (SVD) was defined by strict echocardiographic assessment. The mean follow-up period was 8.6 ± 5.5 years, for a total of 1269 valve-years. Operative mortality rate was 2.0%. Fifty-one late deaths occurred (linearized rate 4.0% per valve-year). Actuarial survival rates averaged 70 ± 4%, 53 ± 6% and 31 ± 7% after 10, 15 and 20 years of follow-up, respectively. Actuarial freedom from SVD at 10, 15 and 20 years was 78 ± 5%, 47 ± 7% and 19 ± 7%, respectively. Reoperation was associated with no operative mortality. Actuarial freedom from reoperation due to SVD at 10, 15 and 20 years was 82 ± 4%, 50 ± 6% and 25 ± 8%, respectively. Competing risk analysis demonstrated an actual risk of explantation secondary to SVD at 20 years of 44 ± 5%. Expected valve durability was 14.2 years for this age group. In the selected patients aged 65 years or younger undergoing mitral valve replacement with a pericardial bioprosthesis, the expected valve durability was 14.2 years. Reoperation for SVD was associated with a low risk of mortality. © The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  19. Bioprosthetic Aortic Valve Durability: A Meta-Regression of Published Studies.

    PubMed

    Wang, Mansen; Furnary, Anthony P; Li, Hsin-Fang; Grunkemeier, Gary L

    2017-09-01

    To compare structural valve deterioration (SVD) among bioprosthetic aortic valve types, a PubMed search found 54 papers containing SVD-free curves extending to at least 10 years. The curves were digitized and fit to Weibull distributions, and the mean times to valve failure (MTTF) were calculated. Twelve valve models were collapsed into four valve types: Medtronic (Medtronic, Minneapolis, MN) and Edwards (Edwards Lifesciences, Irvine, CA) porcine; and Sorin (Sorin Group [now LivaNova], London, United Kingdom) and Edwards pericardial. Meta-regression found MTTF was associated with the patient's age, publication year, SVD definition, and valve type. Sorin pericardial valves had significantly lower risk-adjusted MTTF (higher SVD risk), and there were no significant differences in MTTF among the other three valve types. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Long-term results of aortic valve replacement with Edwards Prima Plus stentless bioprosthesis: eleven years' follow up.

    PubMed

    Auriemma, Stefano; D'Onofrio, Augusto; Brunelli, Massimo; Magagna, Paolo; Paccanaro, Mariemma; Rulfo, Fanny; Fabbri, Alessandro

    2006-09-01

    The Edwards Lifesciences Prima Plus stentless valve (ELSV) is a bioprosthesis manufactured from a porcine aortic root. The study aim was to evaluate late clinical outcomes after aortic valve replacement (AVR) with ELSV implanted as a miniroot in patients with aortic valve disease. Between 1993 and 2004, 318 patients (232 males, 86 females; mean age 69 +/- 9 years; range: 37-83 years) underwent AVR with the ELSV. Preoperatively, 102 patients (32%), 162 (51%) and 54 (17%) were in NYHA classes I/II, III and IV, respectively. Aortic stenosis, aortic regurgitation and combined lesions were present in 124 patients (39%), 114 (36%) and 41 (13%), respectively. Twenty patients (6%) were referred for an acute aortic dissection, 20 (6%) for an aortic root aneurysm, and 139 (44%) had an associated aneurysmal dilatation of the ascending aorta. The ascending aorta was replaced in 159 patients (50%); aortic arch replacement was required in 10 (3%). Coronary artery bypass graft was performed in 86 patients (27%). The follow up was based on clinical data. Operative mortality was 5% (n = 17). There were 49 late deaths (5.2%/pt-yr). Valve-related mortality occurred in 10 patients (1%/pt-yr). Actuarial survival at five and 10 years was 78% and 33%, respectively. Actuarial freedom from valve reoperation and structural valve deterioration at 10 years were 100% and 64%. Actuarial freedom from embolic events and endocarditis at 10 years were 84% and 81%, respectively. The ELSV, when implanted as a miniroot, provided good early and long-term results in terms of survival and freedom from major complications.

  1. Electromechanically Actuated Valve for Controlling Flow Rate

    NASA Technical Reports Server (NTRS)

    Patterson, Paul

    2007-01-01

    A proposed valve for controlling the rate of flow of a fluid would include an electric-motor-driven ball-screw mechanism for adjusting the seating element of the valve to any position between fully closed and fully open. The motor would be of a type that can be electronically controlled to rotate to a specified angular position and to rotate at a specified rate, and the ball screw would enable accurate linear positioning of the seating element as a function of angular position of the motor. Hence, the proposed valve would enable fine electronic control of the rate of flow and the rate of change of flow. The uniqueness of this valve lies in a high degree of integration of the actuation mechanism with the flow-control components into a single, relatively compact unit. A notable feature of this integration is that in addition to being a major part of the actuation mechanism, the ball screw would also be a flow-control component: the ball screw would be hollow so as to contain part of the main flow passage, and one end of the ball screw would be the main seating valve element. The relationships among the components of the valve are best understood by reference to the figure, which presents meridional cross sections of the valve in the fully closed and fully open positions. The motor would be supported by a bracket bolted to the valve body. By means of gears or pulleys and a timing belt, motor drive would be transmitted to a sleeve that would rotate on bearings in the valve body. A ball nut inside the sleeve would be made to rotate with the sleeve by use of a key. The ball screw would pass through and engage the ball nut. A key would prevent rotation of the ball screw in the valve body while allowing the ball screw to translate axially when driven by the ball nut. The outer surface of the ball screw would be threaded only in a mid-length region: the end regions of the outer surface of the ball screw would be polished so that they could act as dynamic sealing surfaces

  2. [Reconstructive surgery of the mitral and tricuspid valves with a Cosgrove-Edwards flexible ring].

    PubMed

    Pugliese, P; Pantani, P; Lusa, A M; Nuti, R; Bongiovanni, M; Conti, F; Biasi, C; Pigini, F; Palmisano, D

    2000-04-01

    Mitral and tricuspid valve asymmetric annular dilation represents the most important mechanism which produces insufficiency. Recent computerized in vitro and in vivo three-dimensional models have been developed in order to better understand the competing factors (annular dilation, displacement of papillary muscles, left and right ventricular geometry). The leading cause of mitral and tricuspid competence is a sphincteric action of both annuli, during systole and diastole, the loss of which produces asymmetric dilation and therefore the absence of cusp coaptation. The Cosgrove-Edwards dynamic ring corrects, alone or in combination with other procedures on the valves, this patho-anatomic feature in a physiological way by restoring the normal annular dimensions and the sphincteric movements during the cardiac cycle. Between June 1998 and May 1999, 30 adult patients underwent mitral (n = 20, Group I) or tricuspid valve repair (n = 10, Group II). Regurgitation was due to a degenerative disease in 13 Group I patients and to ischemic (n = 3), congenital (n = 2) or dilated cardiomyopathy (n = 2) in the others. In Group II the leading cause of insufficiency was functional regurgitation in 7 patients and organic in 3. Associated procedures were carried out in 4 Group I patients and in all Group II patients. Regurgitation was evaluated by transesophageal echocardiography before, during and 3 months after operation. The maximal regurgitant area (MRA) and the grade of insufficiency were evaluated using the equation: MRA < 2 cm2 = grade 0, MRA > 2 < 4 cm2 = 1+, MRA > 4 < 7 cm2 = grade 2+, MRA > 7 < 10 cm2 = 3+, MRA > 10 cm2 = 4+. The operative mortality was 0%. One Group I patient died 3 months after operation due to bronchopneumonia. No patient was reoperated on for plasty failure in both groups during the follow-up. Mitral insufficiency was absent (grade 0) in 17 Group I patients and mild (grade 1+) in 3 at the end of operation. At 3-month postoperative transesophageal

  3. Percutaneous re-revalvulation of the tricuspid valve.

    PubMed

    Gewillig, Marc; Dubois, Christophe

    2011-04-01

    We report a successful percutaneous revalvulation of a dysfunctional tricuspid bioprothesis in an 8-year-old child. Five years after implanting a 25-mm Carpentier-Edwards valve in the tricuspid position, the prosthesis showed significant dysfunction with clinical right heart failure. A 26-mm Edwards-Sapien XT inverted aortic valve was successfully implanted through a 19F sheath using a jugular approach. Such procedure can significantly postpone the need for surgical replacement of a biological valve. Copyright © 2011 Wiley-Liss, Inc.

  4. Precision Photometry and Astrometry from Pan-STARRS

    NASA Astrophysics Data System (ADS)

    Magnier, Eugene A.; Pan-STARRS Team

    2018-01-01

    The Pan-STARRS 3pi Survey has been calibrated with excellent precision for both astrometry and photometry. The Pan-STARRS Data Release 1, opened to the public on 2016 Dec 16, provides photometry in 5 well-calibrated, well-defined bandpasses (grizy) astrometrically registered to the Gaia frame. Comparisons with other surveys illustrate the high quality of the calibration and provide tests of remaining systematic errors in both Pan-STARRS and those external surveys. With photometry and astrometry of roughly 3 billion astronomical objects, the Pan-STARRS DR1 has substantial overlap with Gaia, SDSS, 2MASS and other surveys. I will discuss the astrometric tie between Pan-STARRS DR1 and Gaia and show comparisons between Pan-STARRS and other large-scale surveys.

  5. Early beneficial effect of preservation of papillo-annular continuity in mitral valve replacement on left ventricular function.

    PubMed

    Dilip, D; Chandra, A; Rajashekhar, D; Padmanabhan, M

    2001-05-01

    Impairment of left ventricular (LV) function after mitral valve replacement (MVR) has been the most important factor to determine morbidity and mortality. With this in mind, LV performance in the postoperative period was assessed with and without preservation of papillo-annular continuity in MVR. Between March 1994 and August 1998, a total of 383 valve prostheses (202 MVR, 65 AVR, 58 MVR+AVR) were implanted in 325 patients, 177 of whom underwent MVR with Starr Edwards ball cage prostheses (the study group). Of these 177 patients, 105 had MVR with preservation of the posterior mitral leaflet (group I), and 72 had conventional MVR (group II). Predominant lesions were mitral stenosis in 81, mitral regurgitation in 42, and mixed mitral lesion (MS/MR) in 54. Concomitant tricuspid valve annuloplasty was performed in 13, and atrial septal defect repair in five. Sixteen patients underwent MVR for mitral restenosis. In-vivo performance of the prostheses and LV function was evaluated by M-mode and Doppler echocardiography. At 3-6 months clinical improvement was seen in NYHA class, with reduction in cardiothoracic ratio among patients with preserved papillo-annular continuity, irrespective of lesion type. Significant reductions (p <0.05) were seen in left atrial dimensions (54.10 +/- 8.79 preop. versus 44.64 +/- 8.54 postop.; p <0.05), left ventricular end-diastolic dimensions (LVEDD) (50.84 +/- 10.42 preop. versus 41.21 +/- 7.16 postop.; p <0.05) and end-systolic dimensions (LVESD) (34.76 +/- 7.94 preop. versus 28.81 +/- 5.79 postop.; p <0.05) in patients who had their posterior mitral leaflet preserved with significant improvement in ejection fraction (60.31 +/- 8.22 versus 64.47 +/- 7.93; p <0.05). Further analysis of data in group I patients showed significant reductions in left atrial dimensions, LVESD and peak gradient, along with improved ejection fraction compared with conventional (group II) patients. Deterioration in LV function in patients undergoing conventional

  6. Cracking a tricuspid perimount bioprosthesis to optimize a second transcatheter sapien valve-in-valve placement.

    PubMed

    Brown, Stephen C; Cools, Bjorn; Gewillig, Marc

    2016-09-01

    Bioprosthetic valves degenerate over time. Transcatheter valve-in-valve procedures have become an attractive alternative to surgery. However, every valve increasingly diminishes the diameter of the valvar orifice. We report a 12-year-old female who had a previous transcatheter tricuspid valve-in-valve procedure; cracking the ring of a Carpentier Edwards Perimount valve by means of an ultrahigh pressure balloon allowed implantation of a further larger percutaneous valve. The advantage of this novel approach permits enlarging the inner valve diameter and may facilitate future interventions and prolong time to surgery. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Starr Ranch Renewable Energy Feasibility Study

    EPA Pesticide Factsheets

    Starr Ranch Renewable Energy success story is the summary of a renewable energy study by U.S. EPA Region 6. This publication summarizes the analyses to determine appropriate renewable energy options in Starr Ranch.

  8. Mid-term haemodynamic and clinical results after aortic valve replacement using the Freedom Solo stentless bioprosthesis versus the Carpentier Edwards Perimount stented bioprosthesis.

    PubMed

    van der Straaten, Ellen P J; Rademakers, Leonard M; van Straten, Albert H M; Houterman, Saskia; Tan, M Erwin S H; Soliman Hamad, Mohamed A

    2016-04-01

    The aim of this study was to investigate the mid-term haemodynamic and clinical results after aortic valve replacement (AVR) using the Sorin Freedom Solo (SFS) stentless bioprosthesis, compared with the standard Carpentier Edwards Perimount (CEP) stented bioprosthesis. In this retrospective cohort study of prospectively collected data, 116 patients were included in the SFS group (53 males; median age 74 years, range 56-85 years), and 122 patients in the CEP group (85 males; median age 73 years, range 43-88 years) between July 2007 and January 2013. Echocardiography was performed at 6 weeks after surgery in our centre, and the most recent echocardiography (in our centre or in referring cardiology departments) was requested. Between September 2013 and April 2014, all patients were called by the same researcher to gain clinical follow-up data. Mid-term mortality was 16.4% in the SFS group (19 patients) and 21.3% in the CEP group (26 patients); (P = 0.3). The mean transvalvular gradient was 7.4 ± 3.1 mmHg in the SFS group, and 11.6 ± 3.2 mmHg in the CEP group at 6 weeks postoperatively (P < 0.001). When stratified by labelled valve size, mean gradients were significantly lower in the SFS group for every size (P ≤ 0.03). After 3.3 ± 1.4 years of follow-up, the mean gradient was still significantly lower in the SFS group than that in the CEP group (P < 0.001). Clinical follow-up showed relatively low complication rates. These data suggest that the Sorin Freedom Solo stentless bioprosthesis is as safe as the Carpentier Edwards bioprosthesis, and provides better short- and mid-term haemodynamic performance than the Carpentier Edwards bioprosthesis. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  9. Transcatheter aortic valve implantation in patients with bicuspid aortic valve stenosis.

    PubMed

    Wijesinghe, Namal; Ye, Jian; Rodés-Cabau, Josep; Cheung, Anson; Velianou, James L; Natarajan, Madhu K; Dumont, Eric; Nietlispach, Fabian; Gurvitch, Ronen; Wood, David A; Tay, Edgar; Webb, John G

    2010-11-01

    We evaluated transcatheter aortic valve implantation (TAVI) in high-risk patients with bicuspid aortic valve (BAV) stenosis. TAVI shows promise in the treatment of severe stenosis of triscupid aortic valves, especially in high-risk patients. However, BAV stenosis has been considered a contraindication to TAVI. Eleven patients (age 52 to 90 years) with symptomatic severe BAV stenosis underwent TAVI at 3 Canadian tertiary hospitals between May 2006 and April 2010. All patients were considered high risk for surgical aortic valve replacement. Edwards-SAPIEN transcatheter heart valves (Edwards Lifesciences, Inc., Irvine, California) were used. Transfemoral or transapical access was selected, depending on the adequacy of femoral access. Access was transfemoral in 7 patients and transapical in 4 patients. There were no intraprocedural complications. Significant symptomatic and hemodynamic improvement was observed in 10 of 11 patients. Baseline aortic valve area of 0.65 ± 0.17 cm(2) and mean transaortic pressure gradient of 41 ± 22.4 mm Hg were improved to 1.45 ± 0.3 cm(2) and 13.4 ± 5.7 mm Hg, respectively. Two patients had moderate perivalvular leaks. At the 30-day follow-up there were 2 deaths due to multisystem failure in 2 transapical patients. In 1 patient an undersized, suboptimally positioned, unstable valve required late conversion to open surgery. TAVI in selected high-risk patients with severe BAV stenosis can be successfully performed with acceptable clinical outcomes but will require further evaluation. Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. The Pan-STARRS1 Surveys

    NASA Astrophysics Data System (ADS)

    Chambers, Kenneth C.

    2014-01-01

    Pan-STARRS1 is approaching the completion of the PS1 Science Mission. Operations of the PS1 System include the Observatory, Telescope, 1.4 Gigapixel Camera, Image Processing Pipeline , PSPS relational database and reduced science product software servers. The Pan-STARRS1 Surveys include: (1) A 3pi Steradian Survey, (2) A Medium Deep survey of 10 PS1 footprints spaced around the sky; (3) A solar system survey optimized for Near Earth Objects, (4) a Stellar Transit Survey; and (5) a Deep Survey of M31. The PS1 3pi Survey has now covered the sky north of dec=-30 with more than 12 visits in five bands: g,r,i,z and y or over ~60 epochs per 0.25 arcsec resolution element on the sky. The performance of the PS1 system, sky coverage, cadence, and data quality of the Pan-STARRS1 Surveys will be presented as well as progress in reprocessing of the data taken to date and the plans for the public release of all Pan-STARRS1 data products in the spring of 2015. The Pan-STARRS1 Surveys (PS1) have been made possible through contributions of the Institute for Astronomy, the University of Hawaii, the Pan-STARRS Project Office, the Max-Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns Hopkins University, Durham University, the University of Edinburgh, Queen's University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated, the National Central University of Taiwan, the Space Telescope Science Institute, the National Aeronautics and Space Administration under Grant No. NNX08AR22G issued through the Planetary Science Division of the NASA Science Mission Directorate, the National Science Foundation under Grant No. AST-1238877, the University of Maryland, and Eotvos Lorand University (ELTE).

  11. Bioprosthetic Valve Fracture to Facilitate Transcatheter Valve-in-Valve Implantation.

    PubMed

    Allen, Keith B; Chhatriwalla, Adnan K; Cohen, David J; Saxon, John T; Aggarwal, Sanjeev; Hart, Anthony; Baron, Suzanne; Davis, J Russell; Pak, Alex F; Dvir, Danny; Borkon, A Michael

    2017-11-01

    Valve-in-valve transcatheter aortic valve replacement is less effective in small surgical bioprostheses. We evaluated the feasibility of bioprosthetic valve fracture with a high-pressure balloon to facilitate valve-in-valve transcatheter aortic valve replacement. In vitro bench testing on aortic tissue valves was performed on 19-mm and 21-mm Mitroflow (Sorin, Milan, Italy), Magna and Magna Ease (Edwards Lifesciences, Irvine, CA), Trifecta and Biocor Epic (St. Jude Medical, Minneapolis, MN), and Hancock II and Mosaic (Medtronic, Minneapolis, MN). High-pressure balloons Tru Dilation, Atlas Gold, and Dorado (C.R. Bard, Murray Hill, NJ) were used to determine which valves could be fractured and at what pressure fracture occurred. Mitroflow, Magna, Magna Ease, Mosaic, and Biocor Epic surgical valves were successfully fractured using high-pressures balloon 1 mm larger than the labeled valve size whereas Trifecta and Hancock II surgical valves could not be fractured. Only the internal valve frame was fractured, and the sewing cuff was never disrupted. Manufacturer's rated burst pressures for balloons were exceeded, with fracture pressures ranging from 8 to 24 atmospheres depending on the surgical valve. Testing further demonstrated that fracture facilitated the expansion of previously constrained, underexpanded transcatheter valves (both balloon and self-expanding) to the manufacturer's recommended size. Bench testing demonstrates that the frame of most, but not all, bioprosthetic surgical aortic valves can be fractured using high-pressure balloons. The safety of bioprosthetic valve fracture to optimize valve-in-valve transcatheter aortic valve replacement in small surgical valves requires further clinical investigation. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  12. Transcatheter aortic valve implantation transapical: step by step.

    PubMed

    Walther, Thomas; Möllmann, Helge; van Linden, Arnaud; Kempfert, Jörg

    2011-01-01

    Transcatheter aortic valve implantation (T-AVI) has been introduced into clinical practice to treat high-risk elderly patients with aortic stenosis. T-AVI can be performed by using a retrograde transfemoral (TF), transsubclavian, transaortic, and/or antegrade transapical (TA) approach. For TA-AVI, CE mark approval was granted in 2008 for the Edwards SAPIEN (Edwards Lifesciences, Irvine, CA) prosthesis with the Ascendra delivery system and in 2010 for the second-generation Edwards SAPIEN XT prosthesis and the Ascendra II delivery system, with 23-mm and 26-mm valves. In 2011, CE mark approval has been granted for TA-AVI by using the SAPIEN XT 29-mm prosthesis. Several other devices from different companies (Jenavalve, Jena Valve Inc, Munich, Germany; Embracer, Medtronic Inc, Guilford, CT; Accurate, Symetis Inc, Geneva, Switzerland) have passed "first in man trials" successfully and are being evaluated within multicenter pivotal studies. In this article we will focus on specific aspects of the TA technique for AVI. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Ball feeder for replenishing evaporator feed

    DOEpatents

    Felde, David K.; McKoon, Robert H.

    1993-01-01

    Vapor source material such as uranium, which is to be dropped into a melt in an evaporator, is made into many balls of identical diameters and placed inside a container. An elongated sloping pipe is connected to the container and leads to the evaporator such that these balls can travel sequentially therealong by gravity. A metering valve in this pipe for passing these balls one at a time is opened in response to a signal when it is ascertained by a detector that there is a ball ready to be passed. A gate in the pipe near the evaporator momentarily stops the motion of the traveling ball and is then opened to allow the ball drop into the melt at a reduced speed.

  14. Ball feeder for replenishing evaporator feed

    DOEpatents

    Felde, D.K.; McKoon, R.H.

    1993-03-23

    Vapor source material such as uranium, which is to be dropped into a melt in an evaporator, is made into many balls of identical diameters and placed inside a container. An elongated sloping pipe is connected to the container and leads to the evaporator such that these balls can travel sequentially therealong by gravity. A metering valve in this pipe for passing these balls one at a time is opened in response to a signal when it is ascertained by a detector that there is a ball ready to be passed. A gate in the pipe near the evaporator momentarily stops the motion of the traveling ball and is then opened to allow the ball drop into the melt at a reduced speed.

  15. Bioprosthetic Valve Fracture Improves the Hemodynamic Results of Valve-in-Valve Transcatheter Aortic Valve Replacement.

    PubMed

    Chhatriwalla, Adnan K; Allen, Keith B; Saxon, John T; Cohen, David J; Aggarwal, Sanjeev; Hart, Anthony J; Baron, Suzanne J; Dvir, Danny; Borkon, A Michael

    2017-07-01

    Valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR) may be less effective in small surgical valves because of patient/prosthesis mismatch. Bioprosthetic valve fracture (BVF) using a high-pressure balloon can be performed to facilitate VIV TAVR. We report data from 20 consecutive clinical cases in which BVF was successfully performed before or after VIV TAVR by inflation of a high-pressure balloon positioned across the valve ring during rapid ventricular pacing. Hemodynamic measurements and calculation of the valve effective orifice area were performed at baseline, immediately after VIV TAVR, and after BVF. BVF was successfully performed in 20 patients undergoing VIV TAVR with balloon-expandable (n=8) or self-expanding (n=12) transcatheter valves in Mitroflow, Carpentier-Edwards Perimount, Magna and Magna Ease, Biocor Epic and Biocor Epic Supra, and Mosaic surgical valves. Successful fracture was noted fluoroscopically when the waist of the balloon released and by a sudden drop in inflation pressure, often accompanied by an audible snap. BVF resulted in a reduction in the mean transvalvular gradient (from 20.5±7.4 to 6.7±3.7 mm Hg, P <0.001) and an increase in valve effective orifice area (from 1.0±0.4 to 1.8±0.6 cm 2 , P <0.001). No procedural complications were reported. BVF can be performed safely in small surgical valves to facilitate VIV TAVR with either balloon-expandable or self-expanding transcatheter valves and results in reduced residual transvalvular gradients and increased valve effective orifice area. © 2017 American Heart Association, Inc.

  16. Transcatheter Aortic Valve Replacement for Native Aortic Valve Regurgitation

    PubMed Central

    Spina, Roberto; Anthony, Chris; Muller, David WM

    2015-01-01

    Transcatheter aortic valve replacement with either the balloon-expandable Edwards SAPIEN XT valve, or the self-expandable CoreValve prosthesis has become the established therapeutic modality for severe aortic valve stenosis in patients who are not deemed suitable for surgical intervention due to excessively high operative risk. Native aortic valve regurgitation, defined as primary aortic incompetence not associated with aortic stenosis or failed valve replacement, on the other hand, is still considered a relative contraindication for transcatheter aortic valve therapies, because of the absence of annular or leaflet calcification required for secure anchoring of the transcatheter heart valve. In addition, severe aortic regurgitation often coexists with aortic root or ascending aorta dilatation, the treatment of which mandates operative intervention. For these reasons, transcatheter aortic valve replacement has been only sporadically used to treat pure aortic incompetence, typically on a compassionate basis and in surgically inoperable patients. More recently, however, transcatheter aortic valve replacement for native aortic valve regurgitation has been trialled with newer-generation heart valves, with encouraging results, and new ancillary devices have emerged that are designed to stabilize the annulus–root complex. In this paper we review the clinical context, technical characteristics and outcomes associated with transcatheter treatment of native aortic valve regurgitation. PMID:29588674

  17. Combined pressure regulator and shutoff valve

    NASA Technical Reports Server (NTRS)

    Koch, E. F. (Inventor)

    1974-01-01

    A remotely operable pressure regulator and shutoff valve particularly suited for achieving high resolution and flow control, and positive shutoff is described. The valve is characterized by a spring-loaded ball coaxially aligned with a fluid port to be sealed, a spring-loaded pintle extended through the port into engagement with the ball, for controlling the position, a spring-loaded diaphragm for controlling the position of the pintle, and an axially displaceable spring supported by a movable stop which, in turn, is repositioned by a selectively operable stepper motor. Thus, the pressure-response characteristics for the valve can be varied through a selective repositioning of the stop.

  18. Valve for abrasive material

    DOEpatents

    Gardner, Harold S.

    1982-01-01

    A ball valve assembly for controlling the flow of abrasive particulates including an enlarged section at the bore inlet and an enlarged section at the bore outlet. A refractory ceramic annular deflector is positioned in each of the enlarged sections, substantially extending the useful life of the valve.

  19. The Pan-STARRS1 Small Area Survey 2

    NASA Astrophysics Data System (ADS)

    Metcalfe, N.; Farrow, D. J.; Cole, S.; Draper, P. W.; Norberg, P.; Burgett, W. S.; Chambers, K. C.; Denneau, L.; Flewelling, H.; Kaiser, N.; Kudritzki, R.; Magnier, E. A.; Morgan, J. S.; Price, P. A.; Sweeney, W.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.

    2013-11-01

    The Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1) survey is acquiring multi-epoch imaging in five bands (gP1, rP1, iP1, zP1, yP1) over the entire sky north of declination -30° (the 3π survey). In 2011 July a test area of about 70 deg2 was observed to the expected final depth of the main survey. In this, the first of a series of papers targeting the galaxy count and clustering properties of the combined multi-epoch test area data, we present a detailed investigation into the depth of the survey and the reliability of the Pan-STARRS1 analysis software. We show that the Pan-STARRS1 reduction software can recover the properties of fake sources, and show good agreement between the magnitudes measured by Pan-STARRS1 and those from Sloan Digital Sky Survey. We also examine the number of false detections apparent in the Pan-STARRS1 data. Our comparisons show that the test area survey is somewhat deeper than the Sloan Digital Sky Survey in all bands, and, in particular, the z band approaches the depth of the stacked Sloan Stripe 82 data.

  20. Transapical Mitral Valve Implantation for Native Mitral Valve Stenosis Using a Balloon-Expandable Prosthesis.

    PubMed

    Kiefer, Philipp; Noack, Thilo; Seeburger, Joerg; Hoyer, Alexandro; Linke, Axel; Mangner, Norman; Lehmkuhl, Lukas; Mohr, Friedrich Wilhelm; Holzhey, David

    2017-12-01

    Transcatheter mitral valve implantation (TMVI) is still in its infancy and is mainly limited to valve-in-valve or valve-in-ring implantations. We present the early experience with TMVI for severe calcified native MV stenosis. Between January 2014 and June 2015, 6 of 11 patients screened (mean age, 77.4 ± 6.3 years; 66% men) with severe native mitral valve (MV) stenosis (mean gradient [Pmean], 11.1 ± 2.1 mm Hg; mean effective orifice area [EOA], 0.9 ± 0.12 cm 2 ) underwent transcatheter MV replacement at our institution as a bailout procedure. Conventional surgical procedures were denied in all patients because of severe annular calcification and extensive comorbidities (mean logistic EuroScore, 31.4% ± 8.3%). The Edwards SAPIEN 3 (29 mm) (Edwards Lifesciences, Irvine, CA) was used in all cases. Procedural access was transapical in 5 cases and concomitant to aortic valve replacement through the left atrium through a sternotomy in 1 case. Initial implantation was successful in 100% of the cases. Because of early migration, 1 patient needed a valve-in-valve procedure. Postoperative echocardiography showed no residual mitral regurgitation in 4 cases (66%) and mild regurgitation in 2 cases (34%). Mean gradients were reduced to 4.2 ± 0.6 mm Hg (mean EOA, 2.8 ± 0.4 cm 2) . No patient had a stroke during hospitalization, and 30-day mortality was seen in 1 patient (17%) resulting from pneumonia. TMV implantation using the SAPIEN 3 aortic prosthesis in patients with heavy annular calcification is feasible and represents a reasonable bailout option for inoperable patients. However, several limitations need to be considered in this special patient population. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  1. Energy conservation with automatic flow control valves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phillips, D.

    Automatic flow control valves are offered in a wide range of sizes starting at 1/2 in. with flow rates of 0.5 gpm and up. They are also provided with materials and end connections to meet virtually any fan-coil system requirement. Among these are copper sweat type valves; ductile iron threaded valves; male/female threaded brass valves; and combination flow control/ball valves with union ends.

  2. The Pan-STARRS1 Survey Data Release

    NASA Astrophysics Data System (ADS)

    Chambers, Kenneth C.; Pan-STARRS Team

    2017-01-01

    The first Pan-STARRS1 Science Mission is complete and an initial Data Release 1, or DR1, including a database of measured attributes, stacked images, and metadata of the 3PI Survey, will be available from the STScI MAST archive. This release will contain all stationary objects with mean and stack photometry registered on the GAIA astrometric frame.The characteristics of the Pan-STARRS1 Surveys will be presented, including image quality, depth, cadence, and coverage. Measured attributes include PSF model magnitudes, aperture magnitudes, Kron Magnitudes, radial moments, Petrosian magnitudes, DeVaucoulers, Exponential, and Sersic magnitudes for extended objects. Images include total intensity, variance, and masks.An overview of both DR1 and the second data release DR2, to follow in the spring of 2017, will be presented. DR2 will add all time domain data and individual warped images. We will also report on the status of the Pan-STARRS2 Observatory and ongoing science with Pan-STARRS. The science from the PS1 surveys has included results in many t fields of astronomy from Near Earth Objects to cosmology.The Pan-STARRS1 Surveys have been made possible through contributions of the Institute for Astronomy of the University of Hawaii; the Pan-STARRS Project Office; the Max-Planck Society and its participating institutes: the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching; The Johns Hopkins University; Durham University; the University of Edinburgh; Queen's University Belfast; the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated; the National Central University of Taiwan; the Space Telescope Science Institute; the National Aeronautics and Space Administration under Grants No. NNX08AR22G, NNX12AR65G, NNX14AM74G issued through the Planetary Science Division of the NASA Science Mission Directorate; the National Science Foundation under Grant No. AST

  3. The Pan-STARRS1 Surveys

    NASA Astrophysics Data System (ADS)

    Chambers, Kenneth; Pan-STARRS Team

    2018-01-01

    The Pan-STARRS1 Surveys are complete and the first data release, DR1, is available from the Mikulski Archive for Space Telescopes (MAST) at the Space Telescope Science Institute. The data include a database of measured attributes of 3 billion objects, stacked images, and metadata of the 3pi Steradian Survey. The DR1 contains all stationary objects with mean and stack photometry registered on the GAIA astrometric frame. DR2 is in preparation and will be released this winter with all the individual epoch images and time domain photometry and forced photometry on the individual epoch images. The characteristics of the Pan-STARRS1 Surveys will be presented, including image quality, depth, cadence, and coverage. Measured attributes include PSF model magnitudes, aperture magnitudes, Kron Magnitudes, radial moments, Petrosian magnitudes, DeVaucoulers, Exponential, and Sersic magnitudes for extended objects. Images include total intensity, variance, and masks.An overview of the Pan-STARRS1 Surveys and data releases will be presented together with a brief description of the data collected since the end of the PS1 Science Consortium surveys, and the plans for the upcoming survey with PS1 and PS2 begining in February 2018.

  4. Dynamic behavior of prosthetic aortic tissue valves as viewed by high-speed cinematography.

    PubMed

    Rainer, W G; Christopher, R A; Sadler, T R; Hilgenberg, A D

    1979-09-01

    Using a valve testing apparatus of our own design and with a high-speed (600 to 800 frames per second) 16 mm movie camera, films were made of Hancock porcine, Carpentier-Edwards porcine, and Ionescu-Shiley bovine pericardial valves mounted in the aortic position and cycled under physiological conditions at 72 to 100 beats per minute. Fresh and explanted valves were observed using saline or 36.5% glycerol as the pumping solution. When fresh valves were studied using saline solution as the pumpint fluid, the Hancock and Carpentier-Edwards porcine valves showed high-frequency leaflet vibration, which increased in frequency with higher cycling rates. Abnormal leaflet motion was decreased when glycerol was used as the blood analogue. The Ionescu-Shiley bovine pericardial valve did not show abnormal leaflet motion under these conditions. Conclusions drawn from tissue valve testing studies that use excessively high pulsing rates and pressures (accelerated testing) and saline or water as pumping solutions cannot be transposed to predict the fate of tissue valves in a clinical setting.

  5. The Pan-STARRS search for Near-Earth Objects

    NASA Astrophysics Data System (ADS)

    Wainscoat, Richard J.; Weryk, Robert; Chambers, Kenneth

    2018-01-01

    The Pan-STARRS1 telescope on Haleakala, Hawaii has become the leading discovery telescope for Near-Earth Objects (NEOs), and is now responsible for discovering almost half of all new NEOs, more than half of all larger NEOs, and more than half of all new comets. The survey routinely reaches depths of V=22 or fainter (in dark sky conditions) over an area of approximately 1,000 square degrees per night. The survey strategy will be described. The survey will soon be augmented by the addition of the Pan-STARRS2 telescope, which has similar optics and an improved camera, and which will roughly double the survey power. A sample of the important recent solar system discoveries made by the Pan-STARRS survey will be summarized.

  6. Analysis of hydrodynamic losses for various types of aortic valves

    NASA Astrophysics Data System (ADS)

    Starobin, I. M.; Lupachev, S. P.; Dolgopolov, R. V.; Zaiko, V. M.; Kas'yanov, V. A.; Mungalov, D. D.; Morov, G. V.

    1985-05-01

    The creation of an automated computer-controlled hydraulic stand made it possible to measure the main hydrodynamic parameters of the flow through the investigated HVP and to determine the coefficients of Eq. (2) of fluid flow in the test chamber of the stand. The coefficients found can serve as a criterion of a comparative assessment of the hydrodynamics of HVPs. An analysis of the coefficients showed that the main contribution to pressure losses across ball and disc valves is made by viscous and convective effects. An analysis of inertial losses confirmed the presence of oscillations of the ball closing elements of the AKCh-3-06 valve around the props of the stroke limiters and made it possible to assess them quantitatively. For leaflet valves the contribution of inertial losses to the total pressure losses is more considerable than in the case of disc and ball valves both in the regime of an increase of power of the output and in the regime of a constant power. The mechanical properties of the material of leaflet valves have an effect on the hydrodynamic characteristics. The advantage of the investigated leaflet valves consists not only in that they have smaller total hydraulic losses compared with the other valves, but also in that they provide a high amplitude of pulsations of the blood stream in the case of insufficient contractility of the heart.

  7. High cleanliness globe valve with sine mechanism drive

    NASA Astrophysics Data System (ADS)

    Luo, Hu

    2018-06-01

    This paper gives a new type of quick-opening globe valve for life support pneumatic control system of the safety cabin at underground coal mine. The valve adopts the sine mechanism to transmit the rotating of the handle in the range of 90° to the reciprocating motion of the spool. The mechanism implements the quick-opening function of the valve through controlling the contact and separation between the O-ring and the end face of the valve. Since there is no relative sliding between the sealing interfaces, the valve solute uncontrollable disadvantage wear particles which produced by package ball valve, to ensure high cleanliness in flow path. Traditional transmission mechanism has a reinforcement effect and reduce handle open torque. By the finite element method, the relationship between the contact force and the compression of O-ring is analyzed to provide the boundary condition for the calculation of the rotational torque. Meanwhile the velocity field and pressure field along the flow path are simulated. The caliber size of the valve and the flow resistance coefficient are obtained. There is higher cleanliness, more reliable sealing, smaller handle open torque advantage compared with existing packing ball valve. The above work presents a new technical approach for the design of pneumatic control valve of the safety cabin.

  8. One-year outcomes after rapid-deployment aortic valve replacement.

    PubMed

    Young, Christopher; Laufer, Günther; Kocher, Alfred; Solinas, Marco; Alamanni, Francesco; Polvani, Gianluca; Podesser, Bruno K; Aramendi, Jose Ignacio; Arribas, Jose; Bouchot, Olivier; Livi, Ugolino; Massetti, Massimo; Terp, Kim; Giot, Christophe; Glauber, Mattia

    2018-02-01

    The goals of rapid-deployment aortic valve replacement include facilitation of minimally invasive surgery and reduced aortic crossclamp time. We report the short-term outcomes of a series of 493 patients undergoing rapid-deployment aortic valve replacement with the EDWARDS INTUITY valve system (Edwards Lifesciences, LLC, Irvine, Calif). Assessing Standard oF Care and Clinical Outcomes UsiNg the EDWARDS INTUITY VAlve SysTem in a European multI-center, Active, pOst-market surveillaNce Study was a prospective, multicenter (n = 26) European registry designed to evaluate the safety and performance of the valve system. During rapid-deployment aortic valve replacement, device technical success and crossclamp time were assessed. Procedural outcomes, hemodynamic performance, and various adverse events and clinical outcomes were evaluated up to 2 years. Between 2012 and 2014, 493 of 517 enrolled patients successfully received implants with the study valve (95.4% technical success). Mean crossclamp times for 163 full sternotomies, 128 mini-upper sternotomies, and 36 right anterior thoracotomies isolated aortic valve replacements were 47.3, 52.0, and 73.3 minutes, respectively. Mean follow-up was 1.8 years, with 870 total patient-years of follow-up. Mean effective orifice area increased from 0.72 (baseline) to 1.88 cm 2 , and mean pressure gradient decreased from 47.6 to 9.6 mm Hg (1 year). Mean effective orifice area index increased (0.39-1.01 cm 2 /m 2 ), and 28 of 287 patients (9.8%) exhibited severe prosthesis-patient mismatch at 1 year. After 1 year, 68.1% and 21.7% of patients were in New York Heart Association class I and II, respectively. Freedom from death, major bleeding, major perivalvular leak, reoperation, and device explant at 1 year were 0.935, 0.939, 0.976, 0.975, and 0.983, respectively. These results demonstrate commendable safety and performance of the test valve system over the short term in a broad European setting. Copyright © 2017 The

  9. Long-Term Durability of Bioprosthetic Aortic Valves: Implications From 12,569 Implants

    PubMed Central

    Johnston, Douglas R.; Soltesz, Edward G.; Vakil, Nakul; Rajeswaran, Jeevanantham; Roselli, Eric E.; Sabik, Joseph F.; Smedira, Nicholas G.; Svensson, Lars G.; Lytle, Bruce W.; Blackstone, Eugene H.

    2016-01-01

    Background Increased life expectancy and younger patients’ desire to avoid lifelong anticoagulation requires a better understanding of bioprosthetic valve failure. This study evaluates risk factors associated with explantation for structural valve deterioration (SVD) in a long-term series of Carpentier-Edwards PERIMOUNT aortic valves (AV). Methods From June 1982 to January 2011, 12,569 patients underwent AV replacement with Edwards Lifesciences Carpentier-Edwards PERIMOUNT stented bovine pericardial prostheses, models 2700PM (n = 310) or 2700 (n = 12,259). Mean age was 71 ± 11 years (range, 18 to 98 years). 93% had native AV disease, 48% underwent concomitant coronary artery bypass grafting, and 26% had additional valve surgery. There were 81,706 patient-years of systematic follow-up data available for analysis. Demographics, intraoperative variables, and 27,386 echocardiographic records were used to identify risks for explant for SVD and assess longitudinal changes in transprosthesis gradients using time-varying covariable analyses. Results Three hundred fifty-four explants were performed, with 41% related to endocarditis and 44% to SVD. Actuarial estimates of explant for SVD at 10 and 20 years were 1.9% and 15% overall, respectively, and in patients younger than 60 years, 5.6% and 46%, respectively. Younger age (p < 0.0001), lipid-lowering drugs (p = 0.002), prosthesis–patient mismatch (p = 0.001), and higher postoperative peak and mean AV gradients were associated with explant for SVD (p < 0.0001). The effect of gradient on SVD was greatest in patients younger than 60 years. Conclusions Durability of the Carpentier-Edwards PERIMOUNT aortic valve is excellent even in younger patients. Explant for SVD is related to gradient at implantation, especially in younger patients. Strategies to reduce early postoperative AV gradients, such as root enlargement or more efficient prostheses, should be considered. PMID:25662439

  10. Heated-Pressure-Ball Monopropellant Rocket Engine

    NASA Technical Reports Server (NTRS)

    Greene, William D.

    2005-01-01

    A recent technology disclosure presents a concept for a monopropellant thermal spacecraft thruster that would feature both the simplicity of a typical prior pressure-fed propellant supply system and the smaller mass and relative compactness of a typical prior pump-fed system. The source of heat for this thruster would likely be a nuclear- fission reactor. The propellant would be a cryogenic fluid (a liquefied low-molecular-weight gas) stored in a tank at a low pressure. The propellant would flow from the tank, through a feedline, into three thick-walled spherical tanks, denoted pressure balls, that would be thermally connected to the reactor. Valves upstream and downstream of the pressure balls would be operated in a three-phase cycle in which propellant would flow into one pressure ball while the fluid underwent pressurization through heating in another ball and pressurized propellant was discharged from the remaining ball into the reactor. After flowing through the reactor, wherein it would be further heated, the propellant would be discharged through an exhaust nozzle to generate thrust. A fraction of the pressurized gas from the pressure balls would be diverted to maintain the desired pressure in the tank.

  11. Left main coronary artery obstruction by dislodged native-valve calculus after transcatheter aortic valve replacement.

    PubMed

    Durmaz, Tahir; Ayhan, Huseyin; Keles, Telat; Aslan, Abdullah Nabi; Erdogan, Kemal Esref; Sari, Cenk; Bilen, Emine; Akcay, Murat; Bozkurt, Engin

    2014-08-01

    Transcatheter aortic valve replacement can be an effective, reliable treatment for severe aortic stenosis in surgically high-risk or ineligible patients. However, various sequelae like coronary artery obstruction can occur, not only in the long term, but also immediately after the procedure. We present the case of a 78-year-old woman whose left main coronary artery became obstructed with calculus 2 hours after the transfemoral implantation of an Edwards Sapien XT aortic valve. Despite percutaneous coronary intervention in that artery, the patient died. This case reminds us that early recognition of acute coronary obstruction and prompt intervention are crucial in patients with aortic stenosis who have undergone transcatheter aortic valve replacement.

  12. Left Main Coronary Artery Obstruction by Dislodged Native-Valve Calculus after Transcatheter Aortic Valve Replacement

    PubMed Central

    Durmaz, Tahir; Keles, Telat; Aslan, Abdullah Nabi; Erdogan, Kemal Esref; Sari, Cenk; Bilen, Emine; Akcay, Murat; Bozkurt, Engin

    2014-01-01

    Transcatheter aortic valve replacement can be an effective, reliable treatment for severe aortic stenosis in surgically high-risk or ineligible patients. However, various sequelae like coronary artery obstruction can occur, not only in the long term, but also immediately after the procedure. We present the case of a 78-year-old woman whose left main coronary artery became obstructed with calculus 2 hours after the transfemoral implantation of an Edwards Sapien XT aortic valve. Despite percutaneous coronary intervention in that artery, the patient died. This case reminds us that early recognition of acute coronary obstruction and prompt intervention are crucial in patients with aortic stenosis who have undergone transcatheter aortic valve replacement. PMID:25120396

  13. Kepler K2 Campaign 14 search for supernovae using Pan-STARRS

    NASA Astrophysics Data System (ADS)

    Smartt, S. J.; Smith, K. W.; Rest, A.; Garnavich, P. M.; Tucker, B. E.; Margheim, S.; Kasen, D.; Olling, R.; Shaya, E.; Zenteno, A.; Chambers, K. C.; Huber, M. E.; Flewelling, H.; Magnier, E. A.; Schultz, A.; Lowe, T.; Tonry, J.; Waters, C.; Wright, D. E.; Young, D. R.

    2017-06-01

    12 transients have been discovered as part of the Kepler K2 Campaign 14 search using the Pan-STARRS telescope augmenting the Pan-STARRS Search for Transients (PSST) http://star.pst.qub.ac.uk/ps1threepi/.

  14. The Pan-STARRS PS1 Image Processing Pipeline

    NASA Astrophysics Data System (ADS)

    Magnier, E.

    The Pan-STARRS PS1 Image Processing Pipeline (IPP) performs the image processing and data analysis tasks needed to enable the scientific use of the images obtained by the Pan-STARRS PS1 prototype telescope. The primary goals of the IPP are to process the science images from the Pan-STARRS telescopes and make the results available to other systems within Pan-STARRS. It also is responsible for combining all of the science images in a given filter into a single representation of the non-variable component of the night sky defined as the "Static Sky". To achieve these goals, the IPP also performs other analysis functions to generate the calibrations needed in the science image processing, and to occasionally use the derived data to generate improved astrometric and photometric reference catalogs. It also provides the infrastructure needed to store the incoming data and the resulting data products. The IPP inherits lessons learned, and in some cases code and prototype code, from several other astronomy image analysis systems, including Imcat (Kaiser), the Sloan Digital Sky Survey (REF), the Elixir system (Magnier & Cuillandre), and Vista (Tonry). Imcat and Vista have a large number of robust image processing functions. SDSS has demonstrated a working analysis pipeline and large-scale databasesystem for a dedicated project. The Elixir system has demonstrated an automatic image processing system and an object database system for operational usage. This talk will present an overview of the IPP architecture, functional flow, code development structure, and selected analysis algorithms. Also discussed is the HW highly parallel HW configuration necessary to support PS1 operational requirements. Finally, results are presented of the processing of images collected during PS1 early commissioning tasks utilizing the Pan-STARRS Test Camera #3.

  15. Design and Development of Sequential Rotary Valve

    NASA Technical Reports Server (NTRS)

    D’Orsi, Nicholas; Castillo, Priscilla

    2017-01-01

    Valves are used to regulate the flow of fluids through systems. This rotary valve's main purpose is to fill, pressurize, empty, and vent three smaller tanks with the supply of one larger tank. Many different designs are being taken into consideration, which are each at different stages of development. The furthest along uses three ball valves on a common shaft to open and close their respective ports as the shaft completes one full rotation or cycle. We were tasked with advancing this design to its first test as a plastic model for flow verification, as well as sizing and ordering the necessary O-rings and fasteners. A motor will also be sized to satisfy the torque requirements, and will then be programmed using a Raspberry Pi to rotate the shaft at the calculated speed and dwelling times needed to fill each tank equally. In addition, we have also been advancing designs that use a camshaft and poppets. These are earlier on in their development, currently being sized to replicate the expected flow patterns of the rotary ball valve. Expected outcomes of this valve include bi-directionality, successful sealing under pressure, and accurate cycling.

  16. Liquid blocking check valve

    DOEpatents

    Merrill, John T.

    1984-01-01

    A liquid blocking check valve useful particularly in a pneumatic system utilizing a pressurized liquid fill chamber. The valve includes a floatable ball disposed within a housing defining a chamber. The housing is provided with an inlet aperture disposed in the top of said chamber, and an outlet aperture disposed in the bottom of said chamber in an offset relation to said inlet aperture and in communication with a cutaway side wall section of said housing.

  17. Fluid mechanics of heart valves.

    PubMed

    Yoganathan, Ajit P; He, Zhaoming; Casey Jones, S

    2004-01-01

    Valvular heart disease is a life-threatening disease that afflicts millions of people worldwide and leads to approximately 250,000 valve repairs and/or replacements each year. Malfunction of a native valve impairs its efficient fluid mechanic/hemodynamic performance. Artificial heart valves have been used since 1960 to replace diseased native valves and have saved millions of lives. Unfortunately, despite four decades of use, these devices are less than ideal and lead to many complications. Many of these complications/problems are directly related to the fluid mechanics associated with the various mechanical and bioprosthetic valve designs. This review focuses on the state-of-the-art experimental and computational fluid mechanics of native and prosthetic heart valves in current clinical use. The fluid dynamic performance characteristics of caged-ball, tilting-disc, bileaflet mechanical valves and porcine and pericardial stented and nonstented bioprostheic valves are reviewed. Other issues related to heart valve performance, such as biomaterials, solid mechanics, tissue mechanics, and durability, are not addressed in this review.

  18. Indication for percutaneous aortic valve implantation

    PubMed Central

    Akin, Ibrahim; Kische, Stephan; Rehders, Tim C.; Nienaber, Christoph A.; Rauchhaus, Mathias; Schneider, Henrik; Liebold, Andreas

    2010-01-01

    The incidence of valvular aortic stenosis has increased over the past decades due to improved life expectancy. Surgical aortic valve replacement is currently the only treatment option for severe symptomatic aortic stenosis that has been shown to improve survival. However, up to one third of patients who require lifesaving surgical aortic valve replacement are denied surgery due to high comorbidities resulting in a higher operative mortality rate. In the past such patients could only be treated with medical therapy or percutaneous aortic valvuloplasty, neither of which has been shown to improve mortality. With advances in interventional cardiology, transcatheter methods have been developed for aortic valve replacement with the goal of offering a therapeutic solution for patients who are unfit for surgical therapy. Currently there are two catheter-based treatment systems in clinical application (the Edwards SAPIEN aortic valve and the CoreValve ReValving System), utilizing either a balloon-expandable or a self-expanding stent platform, respectively. PMID:22371763

  19. System for remotely servicing a top loading captive ball valve

    DOEpatents

    Berry, Stephen M.; Porter, Matthew L.

    1996-01-01

    An attachment for facilitating servicing of a valve, the valve including: an assembly composed of a valve seat defining a flow path, a flow control member movable relative to the valve seat for blocking or unblocking the valve seat, and a control device including a stem coupled to the flow control member and operable for moving the flow control member relative to the valve seat; a housing for receiving the assembly, the housing having an opening via which the assembly can be removed from, and installed in, the housing, and the housing having a plurality of threaded studs which surround the opening and project away from the housing; a valve housing cover for closing and sealing the opening in the housing, the cover having a first bore for passage of the stem of the control device when the assembly is installed in the housing and a plurality of second bores each located for passage of a respective stud when the cover closes the opening in the housing. A plurality of threaded nuts are engageable with the studs for securing the cover to the housing when the cover closes the opening in the housing, wherein the attachment comprises: a plurality of nut guide devices removable from the housing and each operatively associated with a respective stud for retaining a respective nut and guiding the respective nut into alignment with the respective stud to enable the respective nut to be rotated into engagement with the respective stud; and aligning the nut guide devices with the studs.

  20. 49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

  1. 49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

  2. 49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

  3. 49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

  4. 49 CFR 372.237 - Cameron, Hidalgo, Starr, and Willacy Counties, TX.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... REGULATIONS EXEMPTIONS, COMMERCIAL ZONES, AND TERMINAL AREAS Commercial Zones § 372.237 Cameron, Hidalgo, Starr, and Willacy Counties, TX. (a) Transportation within a zone comprised of Cameron, Hidalgo, Starr... common control, management, or arrangement for shipment to or from points beyond such zone, is partially...

  5. Transcatheter aortic valve implantation for failing surgical aortic bioprosthetic valve: from concept to clinical application and evaluation (part 2).

    PubMed

    Piazza, Nicolo; Bleiziffer, Sabine; Brockmann, Gernot; Hendrick, Ruge; Deutsch, Marcus-André; Opitz, Anke; Mazzitelli, Domenico; Tassani-Prell, Peter; Schreiber, Christian; Lange, Rüdiger

    2011-07-01

    This study sought to review the acute procedural outcomes of patients who underwent transcatheter aortic valve (TAV)-in-surgical aortic valve (SAV) implantation at the German Heart Center, Munich, and to summarize the existing literature on TAV-in-SAV implantation (n = 47). There are several case reports and small case series describing transcatheter aortic valve implantation for a failing surgical aortic valve bioprosthesis (TAV-in-SAV implantation). From January 2007 to March 2011, 20 out of 556 patients underwent a TAV-in-SAV implantation at the German Heart Center Munich. Baseline characteristics and clinical outcome data were prospectively entered into a dedicated database. The mean patient age was 75 ± 13 years, and the mean logistic European System for Cardiac Operative Risk Evaluation and Society of Thoracic Surgeons' Risk Model scores were 27 ± 13% and 7 ± 4%, respectively. Of the 20 patients, 14 had stented and 6 had stentless surgical bioprostheses. Most cases (12 of 20) were performed via the transapical route using a 23-mm Edwards Sapien prosthesis (Edwards Lifesciences, Irvine, California). Successful implantation of a TAV in a SAV with the patient leaving the catheterization laboratory alive was achieved in 18 of 20 patients. The mean transaortic valve gradient was 20.0 ± 7.5 mm Hg. None-to-trivial, mild, and mild-to-moderate paravalvular aortic regurgitation was observed in 10, 6, and 2 patients, respectively. We experienced 1 intraprocedural death following pre-implant balloon aortic valvuloplasty ("stone heart") and 2 further in-hospital deaths due to myocardial infarction. TAV-in-SAV implantation is a safe and feasible treatment for high-risk patients with failing aortic bioprosthetic valves and should be considered as part of the armamentarium in the treatment of aortic bioprosthetic valve failure. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  6. Effect of different number of players and training regimes on physiological and technical demands of ball-drills in basketball.

    PubMed

    Conte, Daniele; Favero, Terence G; Niederhausen, Meike; Capranica, Laura; Tessitore, Antonio

    2016-01-01

    This study aimed to analyse the effects of two factors (number of players and training regimes) on players' physiological and technical demands in basketball ball-drills. Twenty-one young basketball players performed four different ball-drills (two levels for each factor). The number of players involved was 2vs2 and 4vs4, while ball-drill regimes were continuous and intermittent. Physiological demand was assessed using the percentage of maximal heart rate (%HRmax), Edwards' training load and rating of perceived exertion (RPE). Furthermore, the following technical actions were collected: dribbles, steals, rebounds, turnovers, passes (total, correct, wrong and % of correct pass) and shots (total, scored, missed and % of made shot). A 2 × 2 (number of players × regime) two-way ANOVA with repeated measures was applied for physiological parameters and technical actions. The 2vs2 condition showed higher %HRmax (P < 0.001), Edwards' training load (P < 0.001), RPE (P < 0.001), number of dribbles (P < 0.001), rebounds (P < 0.001), passes [total (P = 0.005) and correct (P = 0.005)] and shots [total (P < 0.001) scored (P < 0.001) and missed (P < 0.001)] than 4vs4. Moreover, the continuous regime revealed higher %HRmax (P < 0.001), Edwards' training load (P < 0.001), RPE (P = 0.006) and dribbles (P < 0.001) than the intermittent regime. This study showed that both number of players and regime are useful variables able to modify basketball ball-drills workload.

  7. Airborne Remote Sensing of the Plata Plume Using STARRS

    DTIC Science & Technology

    2006-09-01

    marine constructions . www.sea-technoJlav.com .byT. RT O ’A" n. -, Airborne Remote Sensing of the Plata Plume Using STARRS A New Generation Microwave...using possibilities of adapting a Seville, MATLAB®-from The Spain-based Construcciones Aero- Mathworks Inc. (Natick, Mas- nduticas SA (CASA) Aviocar C...34 Simula-STARRS was constructed and flight of smaller coastal areas with a preci- tion, vol. 78, pp. 36-55, 2002.tested in July 2003. Since aircraft

  8. Assessing the safety, effectiveness, and quality of life after the STARR procedure for obstructed defecation: results of the German STARR registry.

    PubMed

    Schwandner, Oliver; Fürst, Alois

    2010-06-01

    Internal rectal prolapse and rectocele are frequent clinical findings in patients with obstructed defecation syndrome (ODS). However, there is still no evidence whether stapled transanal rectal resection (STARR) provides a safe and effective surgical option. Therefore, the German STARR registry was initiated to assess safety, effectiveness, and quality of life. The German STARR registry was designed as an interventional, prospective, multicenter audit. Primary outcomes include safety (morbidity and adverse events), effectiveness (ODS, symptom severity, and incontinence scores), and quality of life (PAC-QoL and EQ-5D) documented at baseline and at 6 and 12 months. Statistical evaluation was performed by an independent research organization of clinical epidemiology. Complete data of 379 patients (78% females, mean age 57.8 years) were entered into the registry database. Mean operative time was 40 min, mean hospitalization was 5.5 days. A total of 103 complications and adverse events were reported in 80 patients (21.1%) including staple line complications (minor bleeding, infection, or partial dehiscence; 7.1%), major bleeding (2.9%), and postsurgical stenosis (2.1%). Comparisons of ODS and symptom severity scores (SSS) demonstrated a significant reduction in ODS score between baseline (mean 11.14) and 6 months (mean 6.43), which was maintained at 12 months (mean 6.45), and SSS at preoperative and at 6- and 12-month follow-up (13.02 vs. 7.34 vs. 6.59; paired t test, p < 0.001). Significant reduction in ODS symptoms was matched by an improvement in quality of life as judged by symptom-specific PAC-QoL and generic ED-5Q (utility and visual analog scale) scores and was not associated with an impairment of incontinence score following STARR (p > 0.05). However, 11 patients (2.9%) showed de novo incontinence, and new-onset symptoms of fecal urgency were observed in 25.3% of patients. These data indicate that STARR is a safe and effective procedure. However, conclusions are

  9. Prosthetic Mitral Valve Leaflet Escape

    PubMed Central

    Kim, Darae; Hun, Sin Sang; Cho, In-Jeong; Shim, Chi-Young; Ha, Jong-Won; Chung, Namsik; Ju, Hyun Chul; Sohn, Jang Won

    2013-01-01

    Leaflet escape of prosthetic valve is rare but potentially life threatening. It is essential to make timely diagnosis in order to avoid mortality. Transesophageal echocardiography and cinefluoroscopy is usually diagnostic and the location of the missing leaflet can be identified by computed tomography (CT). Emergent surgical correction is mandatory. We report a case of fractured escape of Edward-Duromedics mitral valve 27 years after the surgery. The patient presented with symptoms of acute decompensated heart failure and cardiogenic shock. She was instantly intubated and mechanically ventilated. After prompt evaluation including transthoracic echocardiography and CT, the escape of the leaflet was confirmed. The patient underwent emergent surgery for replacement of the damaged prosthetic valves immediately. Eleven days after the surgery, the dislodged leaflet in iliac artery was removed safely and the patient recovered well. PMID:23837121

  10. System for remotely servicing a top loading captive ball valve

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berry, S.M.; Porter, M.L.

    1996-06-25

    An attachment for facilitating servicing of a valve is disclosed including: an assembly composed of a valve seat defining a flow path, a flow control member movable relative to the valve seat for blocking or unblocking the valve seat, and a control device including a stem coupled to the flow control member and operable for moving the flow control member relative to the valve seat; a housing for receiving the assembly, the housing having an opening via which the assembly can be removed from, and installed in, the housing, and the housing having a plurality of threaded studs which surroundmore » the opening and project away from the housing; a valve housing cover for closing and sealing the opening in the housing, the cover having a first bore for passage of the stem of the control device when the assembly is installed in the housing and a plurality of second bores each located for passage of a respective stud when the cover closes the opening in the housing. A plurality of threaded nuts are engageable with the studs for securing the cover to the housing when the cover closes the opening in the housing, wherein the attachment comprises: a plurality of nut guide devices removable from the housing and each operatively associated with a respective stud for retaining a respective nut and guiding the respective nut into alignment with the respective stud to enable the respective nut to be rotated into engagement with the respective stud; and aligning the nut guide devices with the studs. 7 figs.« less

  11. System for remotely servicing a top loading captive ball valve

    DOEpatents

    Berry, S.M.; Porter, M.L.

    1996-06-25

    An attachment for facilitating servicing of a valve is disclosed including: an assembly composed of a valve seat defining a flow path, a flow control member movable relative to the valve seat for blocking or unblocking the valve seat, and a control device including a stem coupled to the flow control member and operable for moving the flow control member relative to the valve seat; a housing for receiving the assembly, the housing having an opening via which the assembly can be removed from, and installed in, the housing, and the housing having a plurality of threaded studs which surround the opening and project away from the housing; a valve housing cover for closing and sealing the opening in the housing, the cover having a first bore for passage of the stem of the control device when the assembly is installed in the housing and a plurality of second bores each located for passage of a respective stud when the cover closes the opening in the housing. A plurality of threaded nuts are engageable with the studs for securing the cover to the housing when the cover closes the opening in the housing, wherein the attachment comprises: a plurality of nut guide devices removable from the housing and each operatively associated with a respective stud for retaining a respective nut and guiding the respective nut into alignment with the respective stud to enable the respective nut to be rotated into engagement with the respective stud; and aligning the nut guide devices with the studs. 7 figs.

  12. Transcatheter Heart Valve Selection and Permanent Pacemaker Implantation in Patients With Pre-Existent Right Bundle Branch Block.

    PubMed

    van Gils, Lennart; Tchetche, Didier; Lhermusier, Thibault; Abawi, Masieh; Dumonteil, Nicolas; Rodriguez Olivares, Ramón; Molina-Martin de Nicolas, Javier; Stella, Pieter R; Carrié, Didier; De Jaegere, Peter P; Van Mieghem, Nicolas M

    2017-03-03

    Right bundle branch block is an established predictor for new conduction disturbances and need for a permanent pacemaker (PPM) after transcatheter aortic valve replacement. The aim of the study was to evaluate the absolute rates of transcatheter aortic valve replacement related PPM implantations in patients with pre-existent right bundle branch block and categorize for different transcatheter heart valves. We pooled data on 306 transcatheter aortic valve replacement patients from 4 high-volume centers in Europe and selected those with right bundle branch block at baseline without a previously implanted PPM. Logistic regression was used to evaluate whether PPM rate differed among transcatheter heart valves after adjustment for confounders. Mean age was 83±7 years and 63% were male. Median Society of Thoracic Surgeons score was 6.3 (interquartile range, 4.1-10.2). The following transcatheter valve designs were used: Medtronic CoreValve (n=130; Medtronic, Minneapolis, MN); Edwards Sapien XT (ES-XT; n=124) and Edwards Sapien 3 (ES-3; n=32; Edwards Lifesciences, Irvine, CA); and Boston Scientific Lotus (n=20; Boston Scientific Corporation, Marlborough, MA). Overall permanent pacemaker implantation rate post-transcatheter aortic valve replacement was 41%, and per valve design: 75% with Lotus, 46% with CoreValve, 32% with ES-XT, and 34% with ES-3. The indication for PPM implantation was total atrioventricular block in 98% of the cases. Lotus was associated with a higher PPM rate than all other valves. PPM rate did not differ between ES-XT and ES-3. Ventricular paced rhythm at 30-day and 1-year follow-up was present in 81% at 89%, respectively. Right bundle branch block at baseline is associated with a high incidence of PPM implantation for all transcatheter heart valves. PPM rate was highest for Lotus and lowest for ES-XT and ES-3. Pacemaker dependency remained high during follow-up. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by

  13. OMS engine shutoff valve and actuation system design and evaluation. [for space shuttles

    NASA Technical Reports Server (NTRS)

    Wichmann, H.

    1974-01-01

    Shutoff valve and actuation system concepts that are most suitable for the Orbital Maneuvering Systems engine application were determined. Emphasis was placed on the ten year and 100 mission life requirement, propellant and propellant residue compatibility and weight. It was found that poppet or ball valves utilizing electric or electropneumatic actuation were most applicable. Preliminary design layouts of a number of valve and actuation concepts were prepared and analyzed to make the optimum concept selection. Pneumatic actuation systems were required to feature their own pneumatic supply so that for the quad redundant valve, it was necessary to include two pneumatic supply systems, one for each of the series legs of the quad redundant package. The requirement for the pneumatic package placed heavy reliability, weight, and maintenance penalties upon electropneumatic actuation systems. The two valve and actuation systems concepts selected featured electric torque motor operation and a poppet as well as a ball valve concept with a retractable seal.

  14. Pump, and earth-testable spacecraft capillary heat transport loop using augmentation pump and check valves

    NASA Technical Reports Server (NTRS)

    Baker, David (Inventor)

    1998-01-01

    A spacecraft includes heat-generating payload equipment, and a heat transport system with a cold plate thermally coupled to the equipment and a capillary-wick evaporator, for evaporating coolant liquid to cool the equipment. The coolant vapor is coupled to a condenser and in a loop back to the evaporator. A heated coolant reservoir is coupled to the loop for pressure control. If the wick is not wetted, heat transfer will not begin or continue. A pair of check valves are coupled in the loop, and the heater is cycled for augmentation pumping of coolant to and from the reservoir. This augmentation pumping, in conjunction with the check valves, wets the wick. The wick liquid storage capacity allows the augmentation pump to provide continuous pulsed liquid flow to assure continuous vapor transport and a continuously operating heat transport system. The check valves are of the ball type to assure maximum reliability. However, any type of check valve can be used, including designs which are preloaded in the closed position. The check valve may use any ball or poppet material which resists corrosion. For optimum performance during testing on Earth, the ball or poppet would have neutral buoyancy or be configured in a closed position when the heat transport system is not operating. The ball may be porous to allow passage of coolant vapor.

  15. Prosthetic valve endocarditis 7 months after transcatheter aortic valve implantation diagnosed with 3D TEE.

    PubMed

    Sarı, Cenk; Durmaz, Tahir; Karaduman, Bilge Duran; Keleş, Telat; Bayram, Hüseyin; Baştuğ, Serdal; Özen, Mehmet Burak; Bayram, Nihal Akar; Bilen, Emine; Ayhan, Hüseyin; Kasapkara, Hacı Ahmet; Bozkurt, Engin

    2016-01-01

    Transcatheter aortic valve implantation (TAVI) was introduced as an alternative treatment for patients with severe symptomatic aortic stenosis for whom surgery would be high-risk. Prosthetic aortic valve endocarditis is a serious complication of surgical AVR (SAVR) with high morbidity and mortality. According to recent cases, post-TAVI prosthetic valve endocarditis (PVE) seems to occur very rarely. We present the case of a 75-year-old woman who underwent TAVI (Edwards Saphien XT) with an uneventful postoperative stay. She was diagnosed with endocarditis using three dimensional (3D) echocardiography on the TAVI device 7 months later and she subsequently underwent surgical aortic valve replacement. Little experience of the interpretation of transoesophageal echocardiography (TEE) and the clinical course and effectiveness of treatment strategies in post-TAVI endocarditis exists. We report a case of PVE in a TAVI patient which was diagnosed with three-dimensional transoesophageal echocardiography (3DTEE). Copyright © 2016 Hellenic Cardiological Society. Published by Elsevier B.V. All rights reserved.

  16. Transfemoral aortic valve implantation in severe aortic stenosis patients with prior mitral valve prosthesis

    PubMed Central

    Sarı, Cenk; Baştuğ, Serdal; Kasapkara, Hacı Ahmet; Durmaz, Tahir; Keleş, Telat; Akçay, Murat; Aslan, Abdullah Nabi; Bayram, Nihal Akar; Bozkurt, Engin

    2015-01-01

    Introduction Transcatheter aortic valve implantation for severe symptomatic aortic stenosis in patients with a previous mitral valve prosthesis is technically challenging, and pre-procedural comprehensive assessment of these patients before transcatheter aortic valve implantation is vital for an uncomplicated and successful procedure. Aim We want to share our experience with transcatheter aortic valve implantation in patients with a preexisting functional mitral valve prosthesis and describe a series of important technical and pre-procedural details. Material and methods At our center, 135 patients with symptomatic severe aortic stenosis were treated with transcatheter aortic valve implantation. Six of them with a preexisting mitral valve prosthesis received an Edwards SAPIEN XT valve through the transfemoral route. Results Transcatheter aortic valve implantation was performed successfully in all 6 patients without any deformation of the cobalt-chromium/steel stents of the aortic valve bioprosthesis. Also no distortion or malfunction in the mitral valve prosthesis was observed after the procedure. There were no complications during the hospitalization period. Post-procedural echocardiography revealed no or mild aortic paravalvular regurgitation and normal valve function in all the patients. In addition, serial echocardiographic examination demonstrated that both the stability and function of the aortic and mitral prosthetic valves were normal without any deterioration in the gradients and the degree of the regurgitation at long-term follow-ups. Conclusions Our experience confirms that transcatheter aortic valve implantation is technically feasible in patients with previous mitral valve replacement but comprehensive evaluation of patients by multimodal imaging techniques such as transesophageal echocardiography and multislice computed tomography is mandatory for a successful and safe procedure. PMID:26677380

  17. Functional assessment of human enhancer activities using whole-genome STARR-sequencing.

    PubMed

    Liu, Yuwen; Yu, Shan; Dhiman, Vineet K; Brunetti, Tonya; Eckart, Heather; White, Kevin P

    2017-11-20

    Genome-wide quantification of enhancer activity in the human genome has proven to be a challenging problem. Recent efforts have led to the development of powerful tools for enhancer quantification. However, because of genome size and complexity, these tools have yet to be applied to the whole human genome.  In the current study, we use a human prostate cancer cell line, LNCaP as a model to perform whole human genome STARR-seq (WHG-STARR-seq) to reliably obtain an assessment of enhancer activity. This approach builds upon previously developed STARR-seq in the fly genome and CapSTARR-seq techniques in targeted human genomic regions. With an improved library preparation strategy, our approach greatly increases the library complexity per unit of starting material, which makes it feasible and cost-effective to explore the landscape of regulatory activity in the much larger human genome. In addition to our ability to identify active, accessible enhancers located in open chromatin regions, we can also detect sequences with the potential for enhancer activity that are located in inaccessible, closed chromatin regions. When treated with the histone deacetylase inhibitor, Trichostatin A, genes nearby this latter class of enhancers are up-regulated, demonstrating the potential for endogenous functionality of these regulatory elements. WHG-STARR-seq provides an improved approach to current pipelines for analysis of high complexity genomes to gain a better understanding of the intricacies of transcriptional regulation.

  18. A thin film nitinol heart valve.

    PubMed

    Stepan, Lenka L; Levi, Daniel S; Carman, Gregory P

    2005-11-01

    In order to create a less thrombogenic heart valve with improved longevity, a prosthetic heart valve was developed using thin film nitinol (NiTi). A "butterfly" valve was constructed using a single, elliptical piece of thin film NiTi and a scaffold made from Teflon tubing and NiTi wire. Flow tests and pressure readings across the valve were performed in vitro in a pulsatile flow loop. Bio-corrosion experiments were conducted on untreated and passivated thin film nitinol. To determine the material's in vivo biocompatibility, thin film nitinol was implanted in pigs using stents covered with thin film NiTi. Flow rates and pressure tracings across the valve were comparable to those through a commercially available 19 mm Perimount Edwards tissue valve. No signs of corrosion were present on thin film nitinol samples after immersion in Hank's solution for one month. Finally, organ and tissue samples explanted from four pigs at 2, 3, 4, and 6 weeks after thin film NiTi implantation appeared without disease, and the thin film nitinol itself was without thrombus formation. Although long term testing is still necessary, thin film NiTi may be very well suited for use in artificial heart valves.

  19. Fracture of the wire stent in a Carpentier-Edwards porcine bioprosthesis.

    PubMed

    Griffin, S; Bouboulis, N; Holden, M P

    1993-05-01

    A 60-year-old woman underwent mitral and aortic valve replacement with Carpentier-Edwards supra-annular bioprosthesis in 1986. Six years later rapidly progressing exercise dyspnea and orthopnea made hospital admission necessary. At chest x-ray and cardiac catheter examination one of the wire struts of the mitral bioprosthesis was found completely broken causing cusp prolapse. Surgical findings at reoperation confirmed the diagnosis. No apparent cause of the stent fracture was found.

  20. Concomitant Transapical Transcatheter Valve Implantations: Edwards Sapien Valve for Severe Mitral Regurgitation in a Patient with Failing Mitral Bioprostheses and JenaValve for the Treatment of Pure Aortic Regurgitation.

    PubMed

    Aydin, Unal; Gul, Mehmet; Aslan, Serkan; Akkaya, Emre; Yildirim, Aydin

    2015-04-28

    Transcatheter valve implantation is a novel interventional technique, which was developed as an  alternative therapy for surgical aortic valve replacement in inoperable patients with severe aortic stenosis. Despite limited experience in using transcatheter valve implantation for mitral and aortic regurgitation, transapical transcatheter aortic valve implantation and valve-in-valve implantation for degenerated mitral valve bioprosthesis can be performed in high-risk patients who are not candidates for conventional replacement surgery. In this case, we present the simultaneous transcatheter valve implantation via transapical approach for both degenerated bioprosthetic mitral valve with severe regurgitation and pure severe aortic regurgitation.

  1. Does Undersizing of Transcatheter Aortic Valve Bioprostheses during Valve-in-Valve Implantation Avoid Coronary Obstruction? An In Vitro Study.

    PubMed

    Stock, Sina; Scharfschwerdt, Michael; Meyer-Saraei, Roza; Richardt, Doreen; Charitos, Efstratios I; Sievers, Hans-Hinrich; Hanke, Thorsten

    2017-04-01

    Background  The transcatheter aortic valve-in-valve implantation (TAViVI) is an evolving treatment strategy for degenerated surgical aortic valve bioprostheses (SAVBs) in patients with high operative risk. Although hemodynamics is excellent, there is some concern regarding coronary obstruction, especially in SAVB with externally mounted leaflet tissue, such as the Trifecta (St. Jude Medical Inc., St. Paul, Minnesota, United States). We investigated coronary flow and hydrodynamics before and after TAViVI in a SAVB with externally mounted leaflet tissue (St. Jude Medical, Trifecta) with an undersized transcatheter aortic valve bioprosthesis (Edwards Sapien XT; Edwards Lifesciences LLC, Irvine, California, United States) in an in vitro study. Materials and Methods  An aortic root model was constructed incorporating geometric dimensions known as risk factors for coronary obstruction. Investigating the validity of this model, we primarily performed recommended TAViVI with the Sapien XT (size 26 mm) in a Trifecta (size 25 mm) in a mock circulation. Thereafter, hydrodynamic performance and coronary flow (left/right coronary diastolic flow [lCF/rCF]) after TAViVI with an undersized Sapien XT (size 23 mm) in a Trifecta (size 25 mm) were investigated at two different coronary ostia heights (COHs, 8 and 10 mm). Results  Validation of the model led to significant coronary obstruction ( p  < 0.001). Undersized TAViVI showed no significant reduction with respect to coronary flow (lCF: COH 8 mm, 0.90-0.87 mL/stroke; COH 10 mm, 0.89-0.82 mL/stroke and rCF: COH 8 mm, 0.64-0.60 mL/stroke; COH 10 mm, 0.62-0.58 mL/stroke). Mean transvalvular gradients (4-5 mm Hg, p  < 0.001) increased significantly after TAViVI. Conclusions  In our in vitro model, undersized TAViVI with the balloon-expandable Sapien XT into a modern generation SAVB (Trifecta) successfully avoided coronary flow obstruction. Georg Thieme Verlag KG Stuttgart · New York.

  2. Modified Skvor/Starr approach in the mechanical-thermal noise analysis of condenser microphone.

    PubMed

    Tan, Chee Wee; Miao, Jianmin

    2009-11-01

    Simple analytical expressions of mechanical resistance, such as those formulated by Skvor/Starr, are widely used to describe the mechanical-thermal noise performance of a condenser microphone. However, the Skvor/Starr approach does not consider the location effect of acoustic holes in the backplate and overestimates the total equivalent mechanical resistance and mechanical-thermal noise. In this paper, a modified form of the Skvor/Starr approach is proposed to address this hole location dependent effect. A mode shape factor, which consists of the zero order Bessel and modified Bessel functions, is included in Skvor's mechanical resistance formulation to consider the effect of the hole location in the backplate. With reference to two B&K microphones, the theoretical results of the A-weighted mechanical-thermal noise obtained by the modified Skvor/Starr approach are in good agreements with those reported experimental ones.

  3. Early Outcomes of Sutureless Aortic Valves.

    PubMed

    Hanedan, Muhammet Onur; Mataracı, İlker; Yürük, Mehmet Ali; Özer, Tanıl; Sayar, Ufuk; Arslan, Ali Kemal; Ziyrek, Uğur; Yücel, Murat

    2016-06-01

    In elderly high-risk surgical patients, sutureless aortic valve replacement (AVR) should be an alternative to standard AVR. The potential advantages of sutureless aortic prostheses include reducing cross-clamping and cardiopulmonary bypass (CPB) time and facilitating minimally invasive surgery and complex cardiac interventions, while maintaining satisfactory hemodynamic outcomes and low rates of paravalvular leakage. The current study reports our single-center experience regarding the early outcomes of sutureless aortic valve implantation. Between October 2012 and June 2015, 65 patients scheduled for surgical valve replacement with symptomatic aortic valve disease and New York Heart Association function of class II or higher were included to this study. Perceval S (Sorin Biomedica Cardio Srl, Sallugia, Italy) and Edwards Intuity (Edwards Lifesciences, Irvine, CA, USA) valves were used. The mean age of the patients was 71.15±8.60 years. Forty-four patients (67.7%) were female. The average preoperative left ventricular ejection fraction was 56.9±9.93. The CPB time was 96.51±41.27 minutes and the cross-clamping time was 60.85±27.08 minutes. The intubation time was 8.95±4.19 hours, and the intensive care unit and hospital stays were 2.89±1.42 days and 7.86±1.42 days, respectively. The mean quantity of drainage from chest tubes was 407.69±149.28 mL. The hospital mortality rate was 3.1%. A total of five patients (7.69%) died during follow-up. The mean follow-up time was 687.24±24.76 days. The one-year survival rate was over 90%. In the last few years, several models of valvular sutureless bioprostheses have been developed. The present study evaluating the single-center early outcomes of sutureless aortic valve implantation presents the results of an innovative surgical technique, finding that it resulted in appropriate hemodynamic conditions with acceptable ischemic time.

  4. Early Outcomes of Sutureless Aortic Valves

    PubMed Central

    Hanedan, Muhammet Onur; Mataracı, İlker; Yürük, Mehmet Ali; Özer, Tanıl; Sayar, Ufuk; Arslan, Ali Kemal; Ziyrek, Uğur; Yücel, Murat

    2016-01-01

    Background In elderly high-risk surgical patients, sutureless aortic valve replacement (AVR) should be an alternative to standard AVR. The potential advantages of sutureless aortic prostheses include reducing cross-clamping and cardiopulmonary bypass (CPB) time and facilitating minimally invasive surgery and complex cardiac interventions, while maintaining satisfactory hemodynamic outcomes and low rates of paravalvular leakage. The current study reports our single-center experience regarding the early outcomes of sutureless aortic valve implantation. Methods Between October 2012 and June 2015, 65 patients scheduled for surgical valve replacement with symptomatic aortic valve disease and New York Heart Association function of class II or higher were included to this study. Perceval S (Sorin Biomedica Cardio Srl, Sallugia, Italy) and Edwards Intuity (Edwards Lifesciences, Irvine, CA, USA) valves were used. Results The mean age of the patients was 71.15±8.60 years. Forty-four patients (67.7%) were female. The average preoperative left ventricular ejection fraction was 56.9±9.93. The CPB time was 96.51±41.27 minutes and the cross-clamping time was 60.85±27.08 minutes. The intubation time was 8.95±4.19 hours, and the intensive care unit and hospital stays were 2.89±1.42 days and 7.86±1.42 days, respectively. The mean quantity of drainage from chest tubes was 407.69±149.28 mL. The hospital mortality rate was 3.1%. A total of five patients (7.69%) died during follow-up. The mean follow-up time was 687.24±24.76 days. The one-year survival rate was over 90%. Conclusion In the last few years, several models of valvular sutureless bioprostheses have been developed. The present study evaluating the single-center early outcomes of sutureless aortic valve implantation presents the results of an innovative surgical technique, finding that it resulted in appropriate hemodynamic conditions with acceptable ischemic time. PMID:27298793

  5. Fault Study of Valve Based on Test Analysis and Comparison

    NASA Astrophysics Data System (ADS)

    Cheng, Li; Yang, Wukui; Liang, Tao; Xu, Yu; Chen, Chao

    2017-10-01

    The valve of a certain type of small engine often has the fault phenomenon of abnormal vibration noise and can’t close under the specified pressure, which may cause the engine automatic stop because of valve incomplete close leading to fuel leakage during test and startup on the bench. By test study compared to imported valve with the same use function and test condition valve, and put forward the thinking of improving valve structure, compared no-improved valve to improved valve by adopting Fluent field simulation software. As a result, improved valve can restore close pressure of valve, restrain abnormal vibration noise phenomenon, and effectively compensate compression value of spring because of steel ball contacting position downward with valve casing.

  6. Performance of stented biological valves for right ventricular outflow tract reconstruction.

    PubMed

    Buchholz, Christian; Mayr, Andreas; Purbojo, Ariawan; Glöckler, Martin; Toka, Okan; Cesnjevar, Robert A; Rüffer, André

    2016-12-01

    This retrospective single-centre review presents mid- and long-term results of stented biological valves (SBVs) in the pulmonary position. Fifty-two SBVs (17 Carpentier-Edwards Supraannular; 13 Carpentier-Edwards Perimount; 12 St. Jude Medical Trifecta; 4 Sorin Mitroflow; 4 Sorin Soprano; 2 Sorin More) were implanted between 2000 and 2015. The median valve size, patient age and weight were 23 mm (range 19-27), 22.8 years (range 5-77) and 62.0 kg (range 14-110), respectively. The main cardiac diagnosis was tetralogy of Fallot in 26 patients (50%). Forty-four patients (85%) had previous cardiac surgery; 12 patients (23%) had previous conduit or biological valve replacement. Valve degeneration was defined as a valvular peak pressure gradient >50 mmHg or pulmonary valve regurgitation more than moderate. The mean follow-up was 7.9 ± 5.5 years. Two patients died after 5.8 and 6.1 years of causes not related to SBVs. Eleven SBVs (21%) had to be replaced surgically (n = 6) or interventionally (n = 5) after 9.0 ± 4.1 years due to valve degeneration (n = 8), endocarditis (n = 2) or right ventricular dysfunction (n = 1). The rates of freedom from valve replacement were 100%, 92% [95% confidence interval (CI) 79-97], 81% (CI 64-91) and 60% (CI 40-78) after 1, 5, 10 and 15 years, respectively. Successful interventional valve-in-valve implantation resulted in 100% freedom from surgical valve replacement in all patients older than 19.1 years. Multivariate analysis identified patient age <19.1 years (P = 0.007) as a risk factor for earlier valve degeneration. SBVs in the pulmonary position showed encouraging long-term results in mature patients. The design of SBVs enables interventional valve implantation, postponing the need for reoperation. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  7. Acquired discrete subaortic stenosis late after mitral valve replacement.

    PubMed

    Mohan, Jagdish C; Shukla, Madhu; Mohan, Vishwas; Sethi, Arvind

    2016-09-01

    Although acquired left ventricular outflow obstruction has been reported in a variety of conditions, there are scant reports of its occurrence following mitral valve replacement (MVR). This study describes two female patients, who developed severe discrete subaortic stenosis, five years following MVR. In both cases, the mitral valve was replaced by a porcine Carpentier-Edwards 27-mm bioprosthesis with preservation of mitral valve leaflets. The risk of very late left ventricular outflow tract obstruction after bio-prosthetic MVR with preservation of subvalvular apparatus needs to be kept in mind in symptomatic patients. Copyright © 2016 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

  8. Actuation and system design and evaluation OMS engine shutoff valve, Volume 1. [space shuttles

    NASA Technical Reports Server (NTRS)

    Dunn, V. B.

    1975-01-01

    A technology program was conducted to identify and verify the optimum valve and actuation system concept for the Space Shuttle Orbit Maneuvering System engine. Of major importance to the valve and actuation system selection was the ten-year, 100-mission, 10,000-cycle life requirement, while maintaining high reliability, low leakage, and low weight. Valve and actuation system concepts were comparatively evaluated against past valve failure reports and potential failure modes due to the shuttle mission profile to aid in the selection of the most optimum concept for design, manufacture and verification testing. Two valve concepts were considered during the preliminary design stage; i.e., the moving seat and lifting ball. Two actuation systems were manufactured and tested. Test results demonstrate the viability of a lifting ball concept as well as the applicability of an ac motor actuation system to best meet the requirements of the shuttle mission.

  9. Std 598, valve inspection and testing, sixth edition, September 1990

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1990-01-01

    This book covers inspection, supplementary examination, and pressure test requirements for both resilient-seated and metal-to-metal-seated gate, globe, plug, ball, check, and butterfly valves for the petroleum refinery service. The inspection requirements pertain to inspection by the purchaser and to any supplementary examinations the purchaser may require at the valve manufacturer's plant. The testing requirements cover both required and optional pressure tests by the valve manufacturer at his plant.

  10. Soil salinity detection. [Starr and Cameron Counties, Texas

    NASA Technical Reports Server (NTRS)

    Wiegand, C. L.; Richardson, A. J.; Gausman, H. W.; Leamer, R. W.; Gerbermann, A. H.; Everitt, J. H.; Cuellar, J. A. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. Growth forms and herbage biomass production varied considerably among saline and nonsaline soil range sites in Starr County. Grasses on saline soil sites were shallow-rooted and short whereas on nonsaline sites there was an intermixture of short and midgrass species. Differentiation between primarily undisturbed saline and nonsaline rangelands, in Starr County, is partially possible using film optical density readings from Skylab imagery. Differentiation among eight saline and nonsaline soil sites in Cameron County, using black and white and color film was not possible according to statistical results from both DMRT and correlation analysis. Linear analysis showed that Bendix 24-band MSS data (aircraft) collected at 1700 m and 4800 m, as well as Skylab and LANDSAT-1 MSS data, were significantly correlated to electrical conductivity readings. In Starr County, the best spectral band for detection of saline soil levels, using black and white SO-022 film, was in the 0.6 to 0.7 micron spectral region. In Cameron County, the best spectral bands for detection of saline soil levels were the 2.3 to 2.43 micron, 0.72 to 0.76 micron, 0.69 to 1.75 micron, and 0.7 to 1.1 micron spectral regions.

  11. Understanding how brass ball valves passing certification testing can cause elevated lead in water when installed.

    PubMed

    Triantafyllidou, Simoni; Raetz, Meredith; Parks, Jeffrey; Edwards, Marc

    2012-06-15

    The lead leaching potential of new brass plumbing devices has come under scrutiny as a significant source of lead in drinking water (>300 μg/L) of new buildings around the world. Experiments were conducted using ball valves that were sold as certified and known to have caused problems in practice, in order to better understand how installed products could create such problems, even if they passed "leaching tests" such as National Sanitation Foundation (NSF) Standard 61 Section 8. Diffusion of lead from within the device into water when installed can increase lead leaching by orders of magnitude relative to results of NSF testing, which once only required exposure of very small volumes of water within the device. "Normalization" of the lead-in-water result tended to produce estimates of lead concentration that were much lower than actual lead measured at the tap. Finally, the presence of flux could also dramatically increase lead leaching, whereas high water velocity had relatively little effect. Copyright © 2012. Published by Elsevier Ltd.

  12. Standardized methodology for transfemoral transcatheter aortic valve replacement with the Edwards Sapien XT valve under fluoroscopy guidance.

    PubMed

    Kasel, Albert M; Shivaraju, Anupama; Schneider, Stephan; Krapf, Stephan; Oertel, Frank; Burgdorf, Christof; Ott, Ilka; Sumer, Christian; Kastrati, Adnan; von Scheidt, Wolfgang; Thilo, Christian

    2014-09-01

    To provide a simplified, standardized methodology for a successful transfemoral transcatheter aortic valve replacement (TAVR) procedure with the Sapien XT valve in patients with severe aortic stenosis (AS). TAVR is currently reserved for patients with severe, symptomatic AS who are inoperable or at high operative risk. In many institutions, TAVR is performed under general anesthesia with intubation or with conscious sedation. In addition, many institutions still use transesophageal echo (TEE) during the procedure for aortic root angulations and positioning of the valve prior to implantation. Methods. We enrolled 100 consecutive patients (mean age, 80 ± 7 years; range, 50-94 years; female n=59) with severe symptomatic AS. Annulus measurements were based on computed tomography angiograms. All patients underwent fluoroscopy-guided transfemoral TAVR with little to no sedation and without simultaneous TEE. TAVR was predominantly performed with the use of local and central analgesics; only 36% of our cohort received conscious sedation. Procedural success of TAVR was 99%. Transthoracic echocardiography before discharge excluded aortic regurgitation (AR) >2 in all patients (AR >1; n=6). In-hospital stroke rate was 6%. The vessel closure system was successfully employed in 96%. Major vascular complication rate was 1%. The 30-day mortality was 2%. Fluoroscopy-guided TAVR with the use of just analgesics with or without conscious sedation is safe and effective, and this potentially enables a more time-effective and cost-effective procedure. This paper provides simplified, stepwise guidance on how to perform transfemoral TAVR with the Sapien XT valve.

  13. The Pan-STARRS data server and integrated data query tool

    NASA Astrophysics Data System (ADS)

    Guo, Jhen-Kuei; Chen, Wen-Ping; Lin, Chien-Cheng; Chen, Ying-Tung; Lin, Hsing-Wen

    2013-06-01

    The Pan-STARRS project is operated by an international consortium. Located in Haleakala, Hawaii, the Pan-STARRS telescope system patrols the entire visible sky several times a month, with an aim to identify and characterize varying celestial objects of phenomena or in brightness (supernovae, novae, variable stars, etc) or in position (comets, asteroids, near-earth objects, X-planet etc.) PS1 science mission has started officially from May, 2010 and expects to end in the end of 2013. As of early 2012, every patch of sky observable from Hawaii has been observed in at least 5 bands (g', r', i', z', y') for 5 to 40 epochs. We have set up a data depository at NCU to serve the users in Taiwan. The massive amounts of Pan-STARRS data are downloaded via Internet from the Institute for Astronomy, University of Hawaii whenever new observations are obtained and processed. So far we have stored a total of 200 TB worth of data. In addition to star/galaxy catalogs, a postage stamp server provides access to FITS images. The Pan-STARRS Published Science Products Subsystem (PSPS) has recently passed its operational readiness, that provides users to query individual PS1 measurements. Here we present the data query tool to interface with the PS1 catalogs and postage stamp images, together with other complementary databases such as 2MASS and other data at IRSA (NASA/IPAC Infrared Science Archive).

  14. Recently patented transcatheter aortic valves in clinical trials.

    PubMed

    Neragi-Miandoab, Siyamek; Skripochnik, Edvard; Salemi, Arash; Girardi, Leonard

    2013-12-01

    The most widely used heart valve worldwide is the Edwards Sapien, which currently has 60% of the worldwide transcatheter aortic valve implantation (TAVI) market. The CoreValve is next in line in popularity, encompassing 35% of the worldwide TAVI market. Although these two valves dominate the TAVI market, a number of newer transcatheter valves have been introduced and others are in early clinical evaluation. The new valves are designed to reduce catheter delivery diameter, improve ease of positioning and sealing, and facilitate repositioning or removal. The most recent transcatheter valves for transapical use include Acurate TA (Symetis), Engager (Medtronic), and JenaValve the Portico (St Jude), Sadra Lotus Medical (Boston Scientific), and the Direct Flow Medical. These new inventions may introduce more effective treatment options for high-risk patients with severe aortic stenosis. Improvements in transcatheter valves and the developing variability among them may allow for more tailored approaches with respect to patient's anatomy, while giving operators the opportunity to choose devices they feel more comfortable with. Moreover, introducing new devices to the market will create a competitive environment among producers that will reduce high prices and expand availability. The present review article includes a discussion of recent patents related to Transcatheter Aortic Valves.

  15. Magnetically driven cold valve for 4He

    NASA Astrophysics Data System (ADS)

    Bueno, J.; Blaauwgeers, R.; Partapsing, R.; Taminiau, I.; Jochemsen, R.

    2006-08-01

    We have designed a low temperature valve for liquid helium, which uses a magnetic field gradient and a permanent magnet to close. For closing, it presses a small ruby ball onto a Torlon seat. We present a small valve that is easy to build and easily controlled via two wires. It has a fast response, reliable, and has the advantage that there is no dead volume change on closing and no additional helium line is required to operate.

  16. CT predictors of post-procedural aortic regurgitation in patients referred for transcatheter aortic valve implantation: an analysis of 105 patients.

    PubMed

    Marwan, Mohamed; Achenbach, Stephan; Ensminger, Stefan M; Pflederer, Tobias; Ropers, Dieter; Ludwig, Josef; Weyand, Michael; Daniel, Werner G; Arnold, Martin

    2013-06-01

    Cardiac computed tomography (CT) allows accurate and detailed analysis of the anatomy of the aortic root and valve, including quantification of calcium. We evaluated the correlation between different CT parameters and the degree of post-procedural aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) using the balloon-expandable Edwards Sapien prosthesis. Pre-intervention contrast-enhanced dual source CT data sets of 105 consecutive patients (48 males, mean age 81 ± 6 years, mean logEuroSCORE 34 ± 13%) with symptomatic severe aortic valve stenosis referred for TAVI using the Edwards Sapien prosthesis (Edwards lifesciences, Inc., CA, USA) were analysed. The degrees of aortic valve commissural calcification and annular calcification were visually assessed on a scale from 0 to 3. Furthermore, the degree of aortic valve calcification as quantified by the Agatston score, aortic annulus eccentricity, aortic diameter at the level of the sinus of valsalva and at the sinotubular junction were assessed. Early post-procedural AR was assessed using aortography. Significant AR was defined as angiographic AR of at least moderate degree (AR ≥ 2). Visual assessment of the degree of aortic annular calcification as well as the Agatston score of aortic valve calcium correlated weakly, yet significantly with the degree of post-procedural AR (r = 0.31 and 0.24, p = 0.001 and 0.013, respectively). Compared to patients with AR < 2, patients with AR ≥ 2 showed more severe calcification of the aortic annulus (mean visual scores 1.9 ± 0.6 vs. 1.5 ± 0.6, p = 0.003) as well as higher aortic valve Agatston scores (1,517 ± 861 vs. 1,062 ± 688, p = 0.005). Visual score for commissural calcification did not differ significantly between both groups (mean scores 2.4 ± 0.5 vs. 2.5 ± 0.5, respectively, p = 0.117). No significant correlation was observed between the degree of AR and commissural calcification, aortic annulus eccentricity index or aortic diameters

  17. Vent-induced prosthetic leaflet thrombosis treated by open-heart valve-in-valve implantation.

    PubMed

    Stamm, Christof; Pasic, Miralem; Buz, Semih; Hetzer, Roland

    2015-09-01

    A patient required emergency mitral valve replacement and extracorporeal membrane oxygenation (ECMO) support for acute biventricular failure. The left ventricular (LV) vent inserted via the left upper pulmonary vein induced thrombotic immobilization of a prosthetic valve leaflet, with significant intra-prosthesis regurgitation after ECMO explantation. Therefore, the left atrium was opened on the beating heart during conventional extracorporeal circulation, all prosthesis leaflets were excised and a 29-mm expandable Edwards Sapien prosthesis was inserted within the scaffold of the original prosthesis under direct vision. This case illustrates the benefits and potential problems of LV venting on ECMO support, and a rapid and safe way of replacing the prosthesis leaflets in a critical situation. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  18. Worcester 1 Inch Solenoid Actuated Gas Operated SCHe System Valves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    MISKA, C.R.

    1 inch gas-operated full-port ball valves incorporate a solenoid and limit switches as integral parts of the actuator. These valves are normally open and fail safe to the open position (GOV-1*02 and 1*06 fail closed) to provide a flow path of helium gas to the MCO under helium purge and off-normal conditions when the MCO is isolated.

  19. Worcester 1 Inch Solenoid Actuated Gas Operated SCHe System Valves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    VAN KATWIJK, C.

    1 inch Gas-operated full-port ball valves incorporate a solenoid and limit switches as integral parts of the actuator. These valves are normally open and fail safe to the open position (GOV-1*02 and 1*06 fall closed) to provide a flow path of helium gas to the MCO under helium purge and off-normal conditions when the MCO is isolated.

  20. Worcester 1 Inch Solenoid Actuated Gas Operated SCHe System Valves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    VAN KATWIJK, C.

    1 inch Gas-operated full-port ball valves incorporate a solenoid and limit switches as integral parts of the actuator. These valves are normally open and fail safe to the open position (GOV-1*02 and 1*06 fail closed) to provide a flow path of helium gas to the MCO under helium purge and off-normal conditions when the MCO is isolated.

  1. Optimizing Performance of a Microwave Salinity Mapper: STARRS L-Band Radiometer Enhancements

    DTIC Science & Technology

    2007-05-04

    Contribution Number NRL/JA/ setts at Amherst, along with Quadrant Engineering Inc. 7330-05-5313. (now ProSensing Inc.) and funding from the National...Thus, sampling schemes development of STARRS by Quadrant Engineering can be optimized for particular applications. STARRS began under Naval Research...performance to be optimized. As we show later, a draw- ture, computed as the mean temperature from four back of this approach not found in analog

  2. Total prosthetic replacement of atrioventricular valves in the dog

    PubMed Central

    Den Otter, G.

    1968-01-01

    The free-floating cone and cage valve, described in a previous study as being successful as a substitute for the right atrioventricular valve, does not perform well when it is inserted in the mitral ostium. A tilting cone or disc was constructed and tested in a series of 15 dogs. This prosthesis gave excellent results in 12 animals. The reasons for its failure in the remaining three is discussed. The prosthesis presented has advantages over any ball and cage valve, mainly because of its smaller volume. Images PMID:5654076

  3. Pan-STARRS Data Release 1

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather

    2017-01-01

    We present an overview of the first and second Pan-STARRS data release (DR1 and DR2), and how to use the Published Science Products Subsystem (PSPS) and the Pan-STARRS Science Interface (PSI) to access the images and the catalogs. The data will be available from the STScI MAST archive. The PSPS is an SQLServer database that can be queried via script or web interface. This database has relative photometry and astrometry and object associations, making it easy to do searches across the entire sky as well as tools to generate lightcurves of individual objects as a function of time. Both releases of data use the 3pi survey, which has 5 filters (g,r,i,z,y), roughly 60 epochs (12 per filter) and covers 3/4 of the sky and everything north of -30 degrees declination. The first release of data (DR1) will contain stack images, mean attribute catalogs and static sky catalogs based off of the stacks. The second release of data (DR2) will contain the time domain data. For the images, this will include single exposures that have been detrended and warped. For the catalogs, this will include catalogs of all exposures as well as forced photometry.

  4. In Vitro Hydrodynamic Assessment of a New Transcatheter Heart Valve Concept (the TRISKELE).

    PubMed

    Rahmani, Benyamin; Tzamtzis, Spyros; Sheridan, Rose; Mullen, Michael J; Yap, John; Seifalian, Alexander M; Burriesci, Gaetano

    2017-04-01

    This study presents the in vitro hydrodynamic assessment of the TRISKELE, a new system suitable for transcatheter aortic valve implantation (TAVI), aiming to mitigate the procedural challenges experienced with current technologies. The TRISKELE valve comprises three polymeric leaflet and an adaptive sealing cuff, supported by a novel fully retrievable self-expanding nitinol wire frame. Valve prototypes were manufactured in three sizes of 23, 26, and 29 mm by automated dip-coating of a biostable polymer, and tested in a hydrodynamic bench setup in mock aortic roots of 21, 23, 25, and 27 mm annulus, and compared to two reference valves suitable for equivalent implantation ranges: Edwards SAPIEN XT and Medtronic CoreValve. The TRISKELE valves demonstrated a global hydrodynamic performance comparable or superior to the controls with significant reduction in paravalvular leakage. The TRISKELE valve exhibits enhanced anchoring and improved sealing. The valve is currently under preclinical investigation.

  5. FLUID MECHANICS OF ARTIFICIAL HEART VALVES

    PubMed Central

    Dasi, Lakshmi P; Simon, Helene A; Sucosky, Philippe; Yoganathan, Ajit P

    2009-01-01

    SUMMARY 1. Artificial heart valves have been in use for over five decades to replace diseased heart valves. Since the first heart valve replacement performed with a caged-ball valve, more than 50 valve designs have been developed, differing principally in valve geometry, number of leaflets and material. To date, all artificial heart valves are plagued with complications associated with haemolysis, coagulation for mechanical heart valves and leaflet tearing for tissue-based valve prosthesis. For mechanical heart valves, these complications are believed to be associated with non-physiological blood flow patterns. 2. In the present review, we provide a bird’s-eye view of fluid mechanics for the major artificial heart valve types and highlight how the engineering approach has shaped this rapidly diversifying area of research. 3. Mechanical heart valve designs have evolved significantly, with the most recent designs providing relatively superior haemodynamics with very low aerodynamic resistance. However, high shearing of blood cells and platelets still pose significant design challenges and patients must undergo life-long anticoagulation therapy. Bioprosthetic or tissue valves do not require anticoagulants due to their distinct similarity to the native valve geometry and haemodynamics, but many of these valves fail structurally within the first 10–15 years of implantation. 4. These shortcomings have directed present and future research in three main directions in attempts to design superior artificial valves: (i) engineering living tissue heart valves; (ii) development of advanced computational tools; and (iii) blood experiments to establish the link between flow and blood damage. PMID:19220329

  6. Fluid mechanics of artificial heart valves.

    PubMed

    Dasi, Lakshmi P; Simon, Helene A; Sucosky, Philippe; Yoganathan, Ajit P

    2009-02-01

    1. Artificial heart valves have been in use for over five decades to replace diseased heart valves. Since the first heart valve replacement performed with a caged-ball valve, more than 50 valve designs have been developed, differing principally in valve geometry, number of leaflets and material. To date, all artificial heart valves are plagued with complications associated with haemolysis, coagulation for mechanical heart valves and leaflet tearing for tissue-based valve prosthesis. For mechanical heart valves, these complications are believed to be associated with non-physiological blood flow patterns. 2. In the present review, we provide a bird's-eye view of fluid mechanics for the major artificial heart valve types and highlight how the engineering approach has shaped this rapidly diversifying area of research. 3. Mechanical heart valve designs have evolved significantly, with the most recent designs providing relatively superior haemodynamics with very low aerodynamic resistance. However, high shearing of blood cells and platelets still pose significant design challenges and patients must undergo life-long anticoagulation therapy. Bioprosthetic or tissue valves do not require anticoagulants due to their distinct similarity to the native valve geometry and haemodynamics, but many of these valves fail structurally within the first 10-15 years of implantation. 4. These shortcomings have directed present and future research in three main directions in attempts to design superior artificial valves: (i) engineering living tissue heart valves; (ii) development of advanced computational tools; and (iii) blood experiments to establish the link between flow and blood damage.

  7. Technical pitfalls and tips for the valve-in-valve procedure

    PubMed Central

    2017-01-01

    Transcatheter aortic valve implantation (TAVI) has emerged as a viable treatment modality for patients with severe aortic valve stenosis and multiple co-morbidities. More recent indications include the use of transcatheter heart valves (THV) to treat degenerated bioprosthetic surgical heart valves (SHV), which are failing due to stenosis or regurgitation. Valve-in-valve (VIV) procedures in the aortic position have been performed with a variety of THV devices, although the balloon-expandable SAPIEN valve platform (Edwards Lifesciences Ltd, Irvine, CA, USA) and self-expandable CoreValve platform (Medtronic Inc., MN, USA) have been used in majority of the patients. VIV treatment is appealing as it is less invasive than conventional surgery but optimal patient selection is vital to avoid complications such as malposition, residual high gradients and coronary obstruction. To minimize the risk of complications, thorough procedural planning is critical. The first step is identification of the degenerated SHV, including its model, size, fluoroscopic appearance. Although label size and stent internal diameter (ID) are provided by the manufacturer, it is important to note the true ID. The true ID is the ID of a SHV after the leaflets are mounted and helps determine the optimal size of THV. The second step is to determine the type and size of the THV. Although this is determined in the majority of the cases by user preference, in certain situations one THV may be more suitable than another. As the procedure is performed under fluoroscopy, the third step is to become familiarized with the fluoroscopic appearance of both the SHV and THV. This helps to determine the landmarks for optimal positioning, which in turn determines the gradients and fixation. The fourth step is to assess the risk of coronary obstruction. This is performed with either aortic root angiography or ECG-gated computerised tomography (CT). Finally, the route of approach must be carefully planned. Once these

  8. Science of Ball Lightning (Fire Ball)

    NASA Astrophysics Data System (ADS)

    Ohtsuki, Yoshi-Hiko

    1989-08-01

    The Table of Contents for the full book PDF is as follows: * Organizing Committee * Preface * Ball Lightning -- The Continuing Challenge * Hungarian Ball Lightning Observations in 1987 * Nature of Ball Lightning in Japan * Phenomenological and Psychological Analysis of 150 Austrian Ball Lightning Reports * Physical Problems and Physical Properties of Ball Lightning * Statistical Analysis of the Ball Lightning Properties * A Fluid-Dynamical Model for Ball Lightning and Bead Lightning * The Lifetime of Hill's Vortex * Electrical and Radiative Properties of Ball Lightning * The Candle Flame as a Model of Ball Lightning * A Model for Ball Lightning * The High-Temperature Physico-Chemical Processes in the Lightning Storm Atmosphere (A Physico-Chemical Model of Ball Lightning) * New Approach to Ball Lightning * A Calculation of Electric Field of Ball Lightning * The Physical Explanation to the UFO over Xinjiang, Northern West China * Electric Reconnection, Critical Ionization Velocity, Ponderomotive Force, and Their Applications to Triggered and Ball Lightning * The PLASMAK™ Configuration and Ball Lightning * Experimental Research on Ball Lightning * Performance of High-Voltage Test Facility Designed for Investigation of Ball Lightning * List of Participants

  9. 21. VALVES, GAUGES, AND SEVERAL TYPES OF LIGHTING ALONG ROAD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. VALVES, GAUGES, AND SEVERAL TYPES OF LIGHTING ALONG ROAD AT SOUTH REAR OF TEST STAND 1-A. RP1 TANK FARM IN MIDDLE DISTANCE. Looking northeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  10. The First Pan-Starrs Medium Deep Field Variable Star Catalog

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather

    2013-01-01

    We present the first Pan-Starrs 1 Medium Deep Field Variable Star Catalog (PS1-MDF-VSC). The Pan-Starrs 1 (PS1) telescope is a 1.8 meter survey telescope with a 1.4 Gigapixel camera, and is located in Haleakala, Hawaii. The Medium Deep survey, which consists of 10 fields located uniformly across the sky, totalling 70 square degrees, is observed each night, in 2-3 filters per field, with 8 exposures per filter. We have located and classified several hundred periodic variable stars within the Medium Deep fields, and we present the first catalog listing the properties of these variable stars.

  11. Stentless vs. stented bioprosthesis for aortic valve replacement: A case matched comparison of long-term follow-up and subgroup analysis of patients with native valve endocarditis.

    PubMed

    Schaefer, Andreas; Dickow, Jannis; Schoen, Gerhard; Westhofen, Sumi; Kloss, Lisa; Al-Saydali, Tarik; Reichenspurner, Hermann; Philipp, Sebastian A; Detter, Christian

    2018-01-01

    Current retrospective evidence suggests similar clinical and superior hemodynamic outcomes of the Sorin Freedom Solo stentless aortic valve (SFS) (LivaNova PLC, London, UK) compared to the Carpentier Edwards Perimount stented aortic valve (CEP) (Edwards Lifesciences Inc., Irvine, California, USA). To date, no reports exist describing case-matched long-term outcomes and analysis for treatment of native valve endocarditis (NVE). From 2004 through 2014, 77 consecutive patients (study group, 59.7% male, 68.9 ± 12.5 years, logEuroSCORE II 7.6 ± 12.3%) received surgical aortic valve replacement (SAVR) with the SFS. A control group of patients after SAVR with the CEP was retrieved from our database and matched to the study group regarding 15 parameters including preoperative endocarditis. Acute perioperative outcomes and follow-up data (mean follow-up time 48.7±29.8 months, 95% complete) were retrospectively analyzed. No differences in early mortality occurred during 30-day follow up (3/77; 3.9% vs. 4/77; 5.2%; p = 0.699). Echocardiographic findings revealed lower postprocedural transvalvular pressure gradients (max. 17.0 ± 8.2 vs. 24.5 ± 9.2 mmHg, p< 0.001/ mean pressure of 8.4 ± 4.1 vs. 13.1 ± 5.9 mmHg, p< 0.001) in the SFS group. Structural valve degeneration (SVD) (5.2% vs. 0%; p = 0.04) and valve explantation due to SVD or prosthetic valve endocarditis (PVE) (9.1% vs. 1.3%; p = 0.04) was more frequent in the SFS group. All-cause mortality during follow-up was 20.8% vs. 14.3% (p = 0.397). When patients were divided into subgroups of NVE and respective utilized bioprosthesis, the SFS presented impaired outcomes regarding mortality in NVE cases (p = 0.031). The hemodynamic superiority of the SFS was confirmed in this comparison. However, clinical outcomes in terms of SVD and PVE rates, as well as survival after NVE, were inferior in this study. Therefore, we are reluctant to recommend utilization of the SFS for treatment of NVE.

  12. Pelvic floor function following ventral rectopexy versus STARR in the treatment of obstructed defecation.

    PubMed

    Altomare, D F; Picciariello, A; Memeo, R; Fanelli, M; Digennaro, R; Chetta, N; De Fazio, M

    2018-04-01

    Obstructed defecation syndrome (ODS), most commonly found in females, can be treated by a transanal or abdominal approach with good success rate. Nevertheless, patients may experience de novo or persisting pelvic floor dysfunctions after surgery. The aim of this study was to compare the functional outcome of stapled transanal rectal resection (STARR) and ventral rectopexy (VRP) in a series of ODS patients. Forty-nine female patients who had surgery for ODS between 2006 and 2016 were retrospectively evaluated: 28 (median age 60 years, IQR 54-69 years) had VRP and 21 (median age 58 years, IQR 51-66 years) had STARR. ODS was scored with the ODS score while the overall pelvic floor function was assessed with the three axial perineal evaluation (TAPE) score. Quality-of-life was evaluated by the patient assessment of constipation quality-of-life (PAC-Qol) questionnaire administered preoperatively and after 1 year of follow-up. The preoperative median ODS score and TAPE score were comparable in both groups. After a median follow-up of 12 months (range 12-18 months), the median ODS score was 12 (range 10-20) in the STARR group and 9 (range 3-15) in the VRP one (p = 0.02), while the median TAPE score was 70.5 (IQR 60.6-77.3) in the former and 76.8 (IQR 70.2-89.7) in the latter (p = 0.01). Postoperatively the physical domain of the PAC-QoL score had a median value of 2.74 (IQR 1.7-3.75) in the STARR group compared to 1.5 (IQR 1-2.5) in the VRP group (p = 0.03). No major complications were recorded in either group. VRP and STARR can improve defecation in patients with ODS with minimal complications, but the overall pelvic wellness evaluated by the TAPE score improves significantly only after VRP, suggesting a better performance of VRP than STARR when overall pelvic floor function is concerned.

  13. Transapical tricuspid valve-in-ring implantation: An alternative approach to a challenging clinical scenario.

    PubMed

    Girdauskas, Evaldas; Lauer, Bernward; Kuntze, Thomas

    2018-04-01

    We report on a transapical tricuspid valve-in-ring implantation performed via right ventricular apex using the Sapien-XT-prosthesis. A 57-year-old woman with recurrent episodes of right heart failure and three previous sternotomies, including tricuspid valve repair with a 32 mm Carpentier-Edwards-Classic annuloplasty ring was admitted due to recurrent severe tricuspid regurgitation. Given the excessive surgical risk, a 29 mm Sapien-XT-prosthesis was selected for valve-in-ring implantation. Transapical valve-in-ring implantation procedure was uneventful. Predischarge echocardiography showed only trace paravalvular tricuspid regurgitation in the septal region. Transapical approach via right ventricular apex is a viable alternative for tricuspid valve-in-ring implantation in selected high-risk patients. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. The Ship Tethered Aerostat Remote Sensing System (STARRS): Observations of Small-Scale Surface Lateral Transport During the LAgrangian Submesoscale ExpeRiment (LASER)

    NASA Astrophysics Data System (ADS)

    Carlson, D. F.; Novelli, G.; Guigand, C.; Özgökmen, T.; Fox-Kemper, B.; Molemaker, M. J.

    2016-02-01

    The Consortium for Advanced Research on the Transport of Hydrocarbon in the Environment (CARTHE) will carry out the LAgrangian Submesoscale ExpeRiment (LASER) to study the role of small-scale processes in the transport and dispersion of oil and passive tracers. The Ship-Tethered Aerostat Remote Sensing System (STARRS) will observe small-scale surface dispersion in the open ocean. STARRS is built around a high-lift-capacity (30 kg) helium-filled aerostat. STARRS is equipped with a high resolution digital camera. An integrated GNSS receiver and inertial navigation system permit direct geo-rectification of the imagery. Consortium for Advanced Research on the Transport of Hydrocarbon in the Environment (CARTHE) will carry out the LAgrangian Submesoscale ExpeRiment (LASER) to study the role of small-scale processes in the transport and dispersion of oil and passive tracers. The Ship-Tethered Aerostat Remote Sensing System (STARRS) was developed to produce observational estimates of small-scale surface dispersion in the open ocean. STARRS is built around a high-lift-capacity (30 kg) helium-filled aerostat. STARRS is equipped with a high resolution digital camera. An integrated GNSS receiver and inertial navigation system permit direct geo-rectification of the imagery. Thousands of drift cards deployed in the field of view of STARRS and tracked over time provide the first observational estimates of small-scale (1-500 m) surface dispersion in the open ocean. The STARRS imagery will be combined with GPS-tracked surface drifter trajectories, shipboard observations, and aerial surveys of sea surface temperature in the DeSoto Canyon. In addition to obvious applications to oil spill modelling, the STARRS observations will provide essential benchmarks for high resolution numerical modelsDrift cards deployed in the field of view of STARRS and tracked over time provide the first observational estimates of small-scale (1-100 m) surface dispersion in the open ocean. The STARRS

  15. Charge Diffusion Variations in Pan-STARRS1 CCDs

    NASA Astrophysics Data System (ADS)

    Magnier, Eugene A.; Tonry, J. L.; Finkbeiner, D.; Schlafly, E.; Burgett, W. S.; Chambers, K. C.; Flewelling, H. A.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Metcalfe, N.; Wainscoat, R. J.; Waters, C. Z.

    2018-06-01

    Thick back-illuminated deep-depletion CCDs have superior quantum efficiency over previous generations of thinned and traditional thick CCDs. As a result, they are being used for wide-field imaging cameras in several major projects. We use observations from the Pan-STARRS 3π survey to characterize the behavior of the deep-depletion devices used in the Pan-STARRS 1 Gigapixel Camera. We have identified systematic spatial variations in the photometric measurements and stellar profiles that are similar in pattern to the so-called “tree rings” identified in devices used by other wide-field cameras (e.g., DECam and Hypersuprime Camera). The tree-ring features identified in these other cameras result from lateral electric fields that displace the electrons as they are transported in the silicon to the pixel location. In contrast, we show that the photometric and morphological modifications observed in the GPC1 detectors are caused by variations in the vertical charge transportation rate and resulting charge diffusion variations.

  16. Millisecond Pulsar Companions in SDSS and Pan-Starrs

    NASA Astrophysics Data System (ADS)

    McMann, Natasha; Holley-Bockelmann, Kelly; McLaughlin, Maura; Kaplan, David; NANOGrav

    2018-01-01

    Millisecond pulsars (MSPs) are being timed precisely in hopes of detecting gravitational waves (GWs). In order to detect GWs, pulsars must be studied in great detail. The perturbations in timing caused by binaries must be determined so as not to confuse them with a GW perturbation. This study used a list of published MSPs to determine if any known MSP’s white dwarf companions are located and visible in the Sloan Digital Sky Survey (SDSS) and the Panoramic Survey Telescope and Rapid Response System (Pan-Starrs) Footprints. No new possible companions were discovered but five objects were found in the SDSS and 18, including the same five from SDSS, were found in Pan-Starrs that could be the companion to an MSP. All objects are less than 1.5 arcseconds away from the MSP’s position. In order to verify the object as the companion, the color magnitudes must be compared to those previously published.

  17. VizieR Online Data Catalog: Companions to nearby stars from Pan-STARRS 1 (Deacon+, 2014)

    NASA Astrophysics Data System (ADS)

    Deacon, N. R.; Liu, M. C.; Magnier, E. A.; Aller, K. M.; Best, W. M. J.; Dupuy, T.; Bowler, B. P.; Mann, A. W.; Redstone, J. A.; Burgett, W. S.; Chambers, K. C.; Draper, P. W.; Flewelling, H.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Morgan, J. S.; Metcalfe, N.; Price, P. A.; Tonry, J. L.; Wainscoat, R. J.

    2017-04-01

    Pan-STARRS 1 is a wide-field 1.8m telescope situated on Haleakala on Maui in the Hawaiian Islands. Run by a consortium of astronomical research institutions, it has been surveying the sky north of δ=-30° since 2010 May. Just over half of the telescope's operating time is reserved for the 3π Survey, a multi-filter, multi-epoch survey of three-fourths of the sky (~30,000 deg2). We conducted our search over several iterations of the Pan-STARRS 1 3π database. In all our searches we queried the most up-to-date Pan-STARRS 1 3π database using the Desktop Virtual Observatory software (Magnier et al. 2008, IAU Symp. 248, A Giant Step: from Milli- to Micro-arcsecond Astrometry (Cambridge: Cambridge Univ. Press), 553). Initially, our search involved combining 2MASS and Pan-STARRS 1 data to calculate proper motions in a similar process to that used by Deacon et al. (2011, J/AJ/142/77). For this PS1 + 2MASS search, we required that objects had more than one detection in the yP1 band. PS1 detections were required to have a significance greater than 5σ to be included in the astrometric and photometric solutions of their parent object. We also required that the objects be classified as good quality, point-source detections in both Pan-STARRS 1 and 2MASS. (10 data files).

  18. Successful transfemoral aortic Edwards(®) SAPIEN(®) bioprosthesis implantation without using iodinated contrast media in a woman with severe allergy to contrast agent.

    PubMed

    Leroux, Lionel; Dijos, Marina; Dos Santos, Pierre

    2013-12-01

    Severe anaphylactoid reaction after the use of iodinated contrast media are rare but can contraindicate the use of contrast agent. It was the case of a 53-year-old woman suffering from symptomatic severe aortic stenosis, recused for cardiac surgery because of deleterious effects of chest-wall irradiation, with porcelain aorta. We decided to implant a 23-mm Edwards(®) SAPIEN(®) transcatheter aortic valve via a femoral route without using any contrast media. The implantation was successful after surgical approach of the femoral artery, transesophageal echocardiography guiding, and localization of native leaflets and coronary trunk with catheters. Immediate and one month post-interventional follow-up was favorable and echocardiography showed a good functioning of the aortic bioprosthesis. Although conventional angiography is the best way to visualize the good positioning of the valve before deployment, our case suggests that, in special situations, transfemoral implantation of an Edwards(®) SAPIEN(®) aortic bioprosthesis is feasible without any contrast injection. Copyright © 2012 Wiley Periodicals, Inc.

  19. Optimal design of solenoid valve to minimize cavitation by numerical analysis

    NASA Astrophysics Data System (ADS)

    Ko, Seungbin; Jang, Ilhoon; Song, Simon

    2012-11-01

    Keeping pace with the development of clean energy, hybrid cars and electric vehicles are getting extensive attention recently. In an electronic-control brake system which is essential to those vehicles, a solenoid valve is used to control external hydraulic pressure that boosts up the driver's braking force. However, strong cavitation occurs at the narrow passage between the ball and seat of a solenoid valve due to sudden decrease in pressure, leading to severe damage to the valve. In this study, we investigate the cavitation numerically to discover geometric parameters to affect the cavitation, and an optimal design to minimize the cavitation using optimization technique. As a result, we found four parameters: seat inner radius, seat angle, seat length, and ball radius. Among them, the seat inner radius affects the cavitation most. Also, we found that preventing a sudden reduction in a flow passage is important to reduce cavitation. Finally using an evolutionary algorithm for optimization we minimized cavitation. The optimal design resulted in the maximum vapor volume of fraction of 0.04 while it was 0.7 for reference geometry.

  20. Means for positively seating a piezoceramic element in a piezoelectric valve during inlet gas injection

    DOEpatents

    Wright, Kenneth E.

    1994-01-01

    A piezoelectric valve in a gas delivery system includes a piezoceramic element bonded to a valve seal and disposed over a valve seat, and retained in position by an O-ring and a retainer; an insulating ball normally biased by a preload spring against the piezoceramic element; an inlet gas port positioned such that upon admission of inlet gas into the valve, the piezoceramic element is positively seated. The inlet gas port is located only on the side of the piezoceramic element opposite the seal.

  1. The utility of trans-catheter aortic valve replacement after commercialization: does the European experience provide a glimpse into the future use of this technology in the United States?

    PubMed

    Linke, Axel; Walther, Thomas; Schuler, Gerhard

    2010-03-01

    Treatment of aortic stenosis remains challenging in older individuals, as their perioperative mortality for open heart surgery is increased due to comorbidities. Transcatheter aortic valve implantation using the CoreValve ReValving System (Medtronic, Minneapolis, USA) and the Edwards SAPIEN transcatheter heart valve (THV; Edwards Lifescience, Irvine, California, USA) represents an alternative to conventional valve replacement in elderly patients that have a high risk for conventional surgery. This article summarizes the evidence-base from recent clinical trials. The early results of these landmark studies suggest that transcatheter aortic valve implantation with either one of the prosthesis is feasible, safe, improves hemodynamics and, therefore, might be an alternative to conventional aortic valve replacement in very high-risk patients. However, all of the available transcatheter heart valves have certain disadvantages, limiting their use in daily clinical practice. The process of decision making, which valve to use and which access route to choose is illustrated in this article through clinical case scenarios. Additionally, the lessons learned thus far from the European perspective and the potential impact on the future use in the US are discussed. Despite of the progress in this field, we are still lacking an optimal transcatheter heart valve. Once it is available, we can take the plunge to compare transcatheter valve implantation with convention surgery in severe aortic stenosis!

  2. The Pan-STARRS Survey for Transients (PSST)

    NASA Astrophysics Data System (ADS)

    Huber, Mark; Carter Chambers, Kenneth; Flewelling, Heather; Smartt, Stephen J.; Smith, Ken; Wright, Darryl

    2015-08-01

    The Pan-STARRS1 (PS1) Science Consortium finished the 3Pi survey of the whole sky north of -30 degrees between 2010-2014 in grizy (PS1 specific filters) and the PS1 telescope has been running a wide-field survey for near earth objects, funded by NASA through the NEO Observation Program. This survey takes data in a w-band (wide-band filter spanning g,r,i) in dark time, and combinations of r, i, z and y during bright time. We are now processing these data through the Pan-STARRS IPP difference imaging pipeline and recovering stationary transients. Effectively the 3Pi survey for transients that started during the PS1 Science Consortium is being continued under the new NEO optimized operations mode. The observing procedure in this case is to take a quad of exposures, typically 30-45 seconds separated by 10-20 minutes each, typically revealing high confidence transients (greater than 5-sigma) to depths of i~ 20.7, y~18.3 (AB mags). This cadence may be repeated on subsequent nights in a return pointing.Continuing the public release of the first 880 transients from the PS1 3Pi survey during the search period September 2013 - January 2014, beginning February 2015, the transient events using the data from the the Pan-STARRS NEO Science Consortium are now regularly added. These are mostly supernova candidates, but the list also contains some variable stars, AGN, and nuclear transients. The light curves are too sparsely sampled to be of standalone use, but they may be of use to the community in combining with existing data (e.g. Fraser et al. 2013, ApJ, 779, L8), constraining explosion and rise times (e.g. Nicholl et al. 2013, Nature, 502, 346) as well as many being new discoveries.For additional details visit http://star.pst.qub.ac.uk/ps1threepi/

  3. Comparative study of Contour Transtar and STARR procedure for the treatment of obstructed defecation syndrome (ODS)--feasibility, morbidity and early functional results.

    PubMed

    Isbert, C; Reibetanz, J; Jayne, D G; Kim, M; Germer, C-T; Boenicke, L

    2010-09-01

    Stapled transanal rectal resection (STARR) is a promising new treatment for obstructed defecation syndrome (ODS). It may be performed using either a double-stapling technique (PPH-STARR) or with the new Contour Transtar (CT) device. The aim of this study was to evaluate the two techniques with respect to morbidity and functional outcomes. Patients presenting with ODS were evaluated using standardized clinical and radiological investigations and prospectively entered into a database. A total of 150 Patients were treated with either PPH-STARR (n = 68) or CT (n = 82) and further evaluated at 12 month postoperatively. The mean size of the resected specimen was 27 cm(2) (SD +/-4.86 cm(2)) in the PPH-STARR group and 46 cm(2) (SD +/-10.6 cm(2)) in the CT group [P < 0.001]. Morbidity was 7.3% (n = 5) in the PPH-STARR group and 7.5% (n = 6) in the CT group. The most common complication was minor postoperative bleeding in both groups (PPH-STARR: n = 2, 2.9%; CT: n = 2, 2.4%) Overall there were no septic complications and no surgical re-interventions. There was a tendency for more postoperative pain following CT (n = 3, 3.6%) as compared with PPH-STARR (n = 1, 1.4%). Constipation Scores (CCS) were 15.50 +/- 5.71 in the PPH-STARR group and 15.70 +/- 5.84 in the CT group preoperatively and decreased significantly to 8.25 (SD +/-1.45) and 8.01 (SD +/-2.31) 12-months after surgery. Values did not differ significantly between the two groups. Contour Transtar is as safe and effective as PPH-STARR and provides a true circumferential resection of rectal intussusception. This may benefit selected patients and result in improved long-term durability of the technique.

  4. Detectability of Chelyabinsk-like impactors with Pan-STARRS

    NASA Astrophysics Data System (ADS)

    Micheli, Marco; Wainscoat, Richard J.; Denneau, Larry

    2018-03-01

    In this work we present the results of our analysis of the detectability of an object in the size range of the recent Chelyabinsk impactor under the current discovery and follow-up capabilities, using the specific observational strategy of the Pan-STARRS survey as a reference point. We first discuss the observability of real-life cases inspired by the impact trajectories of 2008 TC3, 2014 AA, the past Earth encounters with 2014 RC and 2015 TB145, the upcoming fly-by of 2012 TC4 and the Chelyabinsk event. We then expand our analysis with the investigation of synthetic impactors with realistic orbital distributions. Among the various conclusions of our analysis, we discuss how the time of first detectability of an object does not necessarily correspond to the moment when that same object can be recognized as an impactor. We also point out how objects discovered only a few days before impact can be immediately identified as impactors, partly thanks to the good astrometric quality that telescopes like Pan-STARRS currently achieve.

  5. Implementation of the Pan-STARRS Image Processing Pipeline

    NASA Astrophysics Data System (ADS)

    Fang, Julia; Aspin, C.

    2007-12-01

    Pan-STARRS, or Panoramic Survey Telescope and Rapid Response System, is a wide-field imaging facility that combines small mirrors with gigapixel cameras. It surveys the entire available sky several times a month, which ultimately requires large amounts of data to be processed and stored right away. Accordingly, the Image Processing Pipeline--the IPP--is a collection of software tools that is responsible for the primary image analysis for Pan-STARRS. It includes data registration, basic image analysis such as obtaining master images and detrending the exposures, mosaic calibration when applicable, and lastly, image sum and difference. In this paper I present my work of the installation of IPP 2.1 and 2.2 on a Linux machine, running the Simtest, which is simulated data to test your installation, and finally applying the IPP to two different sets of UH 2.2m Tek data. This work was conducted by a Research Experience for Undergraduates (REU) position at the University of Hawaii's Institute for Astronomy and funded by the NSF.

  6. Asymptomatic strut fracture in DeBakey-Surgitool aortic valves: incidence, management, and metallurgic aspects.

    PubMed

    Von Der Emde J, J; Eberlein, U; Breme J, J

    1990-01-01

    From August 1971 through November 1972, we implanted 62 Model 2 DeBakey-Surgitool aortic valve prostheses in 62 patients, 4 of whom later had clinically asymptomatic strut fractures. In 1 case, the patient died suddenly, and autopsy revealed detachment of the ball-cage; in each of the other 3 cases, fractures of 2 struts close to the base of the prosthesis were diagnosed fluoroscopically, and the patients underwent successful reoperation. The interval between implantation and reoperation ranged from 11 months to 16 years, 9 months. In 1 patient, retrospective study of chest radiographs revealed that the fracture had been present for 2(1/2) years. Larger valves (>/= A6) were affected significantly more often than smaller ones. We performed metallurgic analysis of 1 prosthesis: results revealed strut wear from fatigue cracking and secondary abrasion. Strut fracture was also promoted by suspension of the cage at right angles to the prosthetic ring and by use of a pyrolytic carbon ball in a titanium cage (i.e., an occluder harder than its holder). Patients with DeBakey-Surgitool aortic valve prostheses should undergo annual radiologic examinations to enable early detection of strut fractures. Prophylactic valve replacement is not indicated.

  7. Ball Screw Actuator Including a Compliant Ball Screw Stop

    NASA Technical Reports Server (NTRS)

    Wingett, Paul T. (Inventor); Hanlon, Casey (Inventor)

    2015-01-01

    An actuator includes a ball nut, a ball screw, and a ball screw stop. The ball nut is adapted to receive an input torque and in response rotates and supplies a drive force. The ball screw extends through the ball nut and has a first end and a second end. The ball screw receives the drive force from the ball nut and in response selectively translates between a retract position and a extend position. The ball screw stop is mounted on the ball screw proximate the first end to translate therewith. The ball screw stop engages the ball nut when the ball screw is in the extend position, translates, with compliance, a predetermined distance toward the first end upon engaging the ball nut, and prevents further rotation of the ball screw upon translating the predetermined distance.

  8. Ball Screw Actuator Including a Compliant Ball Screw Stop

    NASA Technical Reports Server (NTRS)

    Wingett, Paul T. (Inventor); Hanlon, Casey (Inventor)

    2017-01-01

    An actuator includes a ball nut, a ball screw, and a ball screw stop. The ball nut is adapted to receive an input torque and in response rotates and supplies a drive force. The ball screw extends through the ball nut and has a first end and a second end. The ball screw receives the drive force from the ball nut and in response selectively translates between a retract position and a extend position. The ball screw stop is mounted on the ball screw proximate the first end to translate therewith. The ball screw stop engages the ball nut when the ball screw is in the extend position, translates, with compliance, a predetermined distance toward the first end upon engaging the ball nut, and prevents further rotation of the ball screw upon translating the predetermined distance.

  9. Is valve choice a significant determinant of paravalular leak post-transcatheter aortic valve implantation? A systematic review and meta-analysis.

    PubMed

    O'Sullivan, Katie E; Gough, Aideen; Segurado, Ricardo; Barry, Mitchel; Sugrue, Declan; Hurley, John

    2014-05-01

    Paravalvular regurgitation (PVR) following transcatheter aortic valve implantation (TAVI) is associated with poor survival. The two main valve delivery systems used to date differ significantly in both structure and deployment technique. The primary objective of this study was to perform a systematic review and meta-analysis of studies identifying PVR in patients post-TAVI using Medtronic CoreValve (MCV) and Edward Sapien (ES) valves in order to identify whether a significant difference exists between valve types. The secondary objective was to identify additional factors predisposing to PVR to provide an overview of the other associated considerations. A systematic review and meta-analysis of the current literature to identify PVR rate in patients with MCV and ES valves was performed. We also sought to examine other factors predisposing to PVR. A total of 5910 patients were identified from 9 studies. PVR rates for MCV and ES were analysed. MCV was associated with a higher PVR rate of 15.75% [95% confidence interval (CI) 12.48-19.32] compared with ES 3.93% [95% CI 1.05-8.38]. We separately reviewed predisposing factors associated with PVR. A formal comparison of the MCV and ES valve leakage rates by mixed-effects meta-regression with a fixed-effect moderator variable for valve type (MCV or ES) suggested a statistically significant difference in leakage rate between the two valve types (P = 0.0002). Unfavourable anatomical and pathological factors as well as valve choice have an impact on rates of PVR. Additionally, certain anatomical features dictate valve choice. A direct comparison of all the predisposing factors at this time is not possible and will require prospective multivariate analysis. There is, however, a significant difference in the PVR rates between valves based on the published observational data available to date. The ES valve associated with a lower incidence of PVR overall; therefore, we conclude that valve choice is indeed a significant

  10. Registry of transcatheter aortic-valve implantation in high-risk patients.

    PubMed

    Gilard, Martine; Eltchaninoff, Hélène; Iung, Bernard; Donzeau-Gouge, Patrick; Chevreul, Karine; Fajadet, Jean; Leprince, Pascal; Leguerrier, Alain; Lievre, Michel; Prat, Alain; Teiger, Emmanuel; Lefevre, Thierry; Himbert, Dominique; Tchetche, Didier; Carrié, Didier; Albat, Bernard; Cribier, Alain; Rioufol, Gilles; Sudre, Arnaud; Blanchard, Didier; Collet, Frederic; Dos Santos, Pierre; Meneveau, Nicolas; Tirouvanziam, Ashok; Caussin, Christophe; Guyon, Philippe; Boschat, Jacques; Le Breton, Herve; Collart, Frederic; Houel, Remi; Delpine, Stephane; Souteyrand, Geraud; Favereau, Xavier; Ohlmann, Patrick; Doisy, Vincent; Grollier, Gilles; Gommeaux, Antoine; Claudel, Jean-Philippe; Bourlon, Francois; Bertrand, Bernard; Van Belle, Eric; Laskar, Marc

    2012-05-03

    Transcatheter aortic-valve implantation (TAVI) is an emerging intervention for the treatment of high-risk patients with severe aortic stenosis and coexisting illnesses. We report the results of a prospective multicenter study of the French national transcatheter aortic-valve implantation registry, FRANCE 2. All TAVIs performed in France, as listed in the FRANCE 2 registry, were prospectively included in the study. The primary end point was death from any cause. A total of 3195 patients were enrolled between January 2010 and October 2011 at 34 centers. The mean (±SD) age was 82.7±7.2 years; 49% of the patients were women. All patients were highly symptomatic and were at high surgical risk for aortic-valve replacement. Edwards SAPIEN and Medtronic CoreValve devices were implanted in 66.9% and 33.1% of patients, respectively. Approaches were either transarterial (transfemoral, 74.6%; subclavian, 5.8%; and other, 1.8%) or transapical (17.8%). The procedural success rate was 96.9%. Rates of death at 30 days and 1 year were 9.7% and 24.0%, respectively. At 1 year, the incidence of stroke was 4.1%, and the incidence of periprosthetic aortic regurgitation was 64.5%. In a multivariate model, a higher logistic risk score on the European System for Cardiac Operative Risk Evaluation (EuroSCORE), New York Heart Association functional class III or IV symptoms, the use of a transapical TAVI approach, and a higher amount of periprosthetic regurgitation were significantly associated with reduced survival. This prospective registry study reflected real-life TAVI experience in high-risk elderly patients with aortic stenosis, in whom TAVI appeared to be a reasonable option. (Funded by Edwards Lifesciences and Medtronic.).

  11. High-pressure cryogenic valves for the Vulcain rocket motor

    NASA Astrophysics Data System (ADS)

    Garceau, P.; Meyer, F.

    The high-pressure valve developed to control the flow of liquid oxygen or hydrogen into the gas generator of the ESA Vulcain rocket motor is described. The spherical ball-seal design employed provides high reliability over a service lifetime of 5000 on-off actuations at temperatures 20-350 K and pressures up to 200 bar. Leakage is limited to a few cu cm/sec of hydrogen at 20 K. The steps in the development process, from the definition of the valve specifications to the fabrication and testing phase are reviewed, and the final design is shown in drawings, diagrams, and photographs.

  12. Successful simultaneous ipsilateral stenting of common iliac artery stenosis and transfemoral aortic valve replacement.

    PubMed

    Aslan, Abdullah Nabi; Kasapkara, Hacı Ahmet; Sivri, Serkan; Güney, Murat Can; Bozkurt, Engin

    2017-01-01

    Transcatheter aortic valve replacement (TAVR) was designed to treat elderly patients with severe aortic stenosis at high risk for surgery, and is most commonly performed with retrograde approach through femoral arteries. However, in up to 30% of cases, it is either not possible to use this access route or it is considered to have high risk of vascular injury. Alternative approaches have been described for patients with no suitable femoral access: trans-subclavian, transaortic, or direct aortic access; however, since the introduction of new valves deployed with low-profile delivery systems, another alternative transcatheter approach has been discovered. Presently described is experience in 2 cases in which patients were treated with transfemoral TAVR using Edwards SAPIEN 3 transcatheter heart valves immediately following ipsilateral common iliac artery stenting.

  13. Debiasing the Distant Solar System Populations Using Pan-STARRS1

    NASA Astrophysics Data System (ADS)

    Lilly Schunova, Eva; Weryk, Robert J.; Chastel, Serge; Denneau, Larry; Jedicke, Robert; Wainscoat, Richard J.; Chambers, Kenneth C.

    2017-10-01

    We discuss our on-going effort to identify Trans-Neptunian Objects (TNOs) in the Pan-STARRS1 dataset, and to debias the size-frequency distributions (SFD) of detected TNO sub-populations in order to estimate their true population sizes. To measure our detection efficiency we used the model of Grav et al. (2011)[1], which includes Kuiper belt Objects (KBOs), Scattered Disc Objects (SDOs), and Centaurs. Our debiasing method accounts for the per-chip CCD sensitivity as well as CCD cell gaps. The search method for finding distant Solar System objects, which was developed for our initial work (Weryk et al., 2016)[2], led to discovery of 29 Centaurs, 243 KBOs and 61 SDOs from Pan-STARRS data spanning years 2010-2015. Our work is extended using more recent PS1 data.[1] Grav, T., et al. (2011), Publications of the Astronomical Society of Pacific, Volume 123, Issue 902, pp. 423.[2] Weryk, R.J., et al. (2016), eprint arXiv:1607.04895.

  14. Transcatheter aortic valve-in-valve implantation for severe bioprosthetic stenosis after Bentall operation using a homograft in a patient with Behçet's disease.

    PubMed

    Joo, Hyung Joon; Hong, Soon Jun; Yu, Cheol Woong

    2015-03-01

    A 43-year-old man presented with severe aortic stenosis. Eight years previously, he had undergone primary surgical aortic valve replacement (AVR) for severe aortic regurgitation, but one year later developed cardiac arrest and complete atrioventricular block as a result of non-bacterial thrombotic endocarditis with severe valvular dehiscence. Following the diagnosis of prosthetic valve failure caused by Behçet's disease, the patient underwent a Bentall operation using 23 mm aortic homograft with permanent pacemaker implantation and coronary artery bypass grafting. Subsequently, he was stable with steroid administration and azathioprine for seven years after the second operation, but recently suffered from severe dyspnea and chest pain. Echocardiography revealed the development of severe aortic stenosis. A preprocedural evaluation demonstrated a porcelain aorta with severe calcification in the previous homograft valve on computed tomography, and critical stenosis at the ostium of the left circumflex artery on coronary angiography. After percutaneous coronary intervention for the ostium of the left circumflex artery, a transcatheter AVR was successfully performed using a 26 mm Edwards SAPIEN XT valve. The patient recovered without any complications after the procedure. This is the first report of a successful transcatheter aortic valve-in valve implantation for severe homograft aortic stenosis after a Bentall operation, using a homograft, in a patient with Behçet's disease.

  15. Aperture Valve for the Mars Organic Molecule Analyzer (MOMA)

    NASA Technical Reports Server (NTRS)

    Engler, Charles; Canham, John

    2014-01-01

    NASA's participation in the multi-nation ExoMars 2018 Rover mission includes a critical astrobiology Mass Spectrometer Instrument on the Rover called the Mars Organic Molecule Analyzer (MOMA). The Aperture Valve is a critical electromechanical valve used by the Mass Spectrometer to facilitate the transfer of ions from Martian soil to the Mass Spectrometer for analysis. The MOMA Aperture Valve development program will be discussed in terms of the initial valve design and subsequent improvements that resulted from prototype testing. The initial Aperture Valve concept seemed promising, based on calculations and perceived merits. However, performance results of this design were disappointing, due to delamination of TiN and DLC coatings applied to the titanium base metals, causing debris from the coatings to seize the valve. While peer reviews and design trade studies are important forums to vet a concept design, results from testing should not be underestimated. Despite the lack of development progress to meet requirements, valuable information from weakness discovered in the initial Valve design was used to develop a second, more robust Aperture Valve. Based on a check-ball design, the ETU / flight valve design resulted in significantly less surface area to create the seal. Moreover, PVD coatings were eliminated in favor of hardened, non-magnetic corrosion resistant alloys. Test results were impressive, with the valve achieving five orders of magnitude better sealing leak rate over end of life requirements. Cycle life was equally impressive, achieving 280,000 cycles without failure.

  16. Aperture Valve for the Mars Organic Molecule Analyzer (MOMA)

    NASA Technical Reports Server (NTRS)

    Hakun, Claef F.; Engler, Charles D.; Barber, Willie E.; Canham, John S.

    2014-01-01

    NASA's participation in the multi-nation ExoMars 2018 Rover mission includes a critical astrobiology Mass Spectrometer Instrument on the Rover called the Mars Organic Molecule Analyzer (MOMA). The Aperture Valve is a critical electromechanical valve used by the Mass Spectrometer to facilitate the transfer of ions from Martian soil to the Mass Spectrometer for analysis. The MOMA Aperture Valve development program will be discussed in terms of the Initial valve design and subsequent improvements that resulted from prototype testing. The Initial Aperture Valve concept seemed promising, based on calculations and perceived merits. However, performance results of this design were disappointing, due to delamination of TiN and DLC coatings applied to the Titanium base metals, causing debris from the coatings to seize the valve. While peer reviews and design trade studies are important forums to vet a concept design, results from testing should not be underestimated.Despite the lack of development progress to meet requirements, valuable information from weakness discovered in the Initial Valve design was used to develop a second, more robust Aperture valve. Based on a check-ball design, the ETU flight valve design resulted in significantly less surface area to create the seal. Moreover, PVD coatings were eliminated in favor of hardened, nonmagnetic corrosion resistant alloys. Test results were impressive, with the valve achieving five orders of magnitude better sealing leak rate over end of life requirements. Cycle life was equally impressive, achieving 280,000 cycles without failure.

  17. Aperture Valve for the Mars Organic Molecule Analyzer (MOMA)

    NASA Technical Reports Server (NTRS)

    Engler, Charles D.; Canham, John S.

    2014-01-01

    NASA's participation in the multi-nation ExoMars 2018 Rover mission includes a critical astrobiology Mass Spectrometer Instrument on the Rover called the Mars Organic Molecule Analyzer (MOMA). The Aperture Valve is a critical electromechanical valve used by the Mass Spectrometer to facilitate the transfer of ions from Martian soil to the Mass Spectrometer for analysis. The MOMA Aperture Valve development program will be discussed in terms of the Initial valve design and subsequent improvements that resulted from prototype testing. The Initial Aperture Valve concept seemed promising, based on calculations and perceived merits. However, performance results of this design were disappointing, due to delamination of TiN and DLC coatings applied to the Titanium base metals, causing debris from the coatings to seize the valve. While peer reviews and design trade studies are important forums to vet a concept design, results from testing should not be underestimated. Despite the lack of development progress to meet requirements, valuable information from weakness discovered in the Initial Valve design was used to develop a second, more robust Aperture valve. Based on a check-ball design, the ETU /flight valve design resulted in significantly less surface area to create the seal. Moreover, PVD coatings were eliminated in favor of hardened, nonmagnetic corrosion resistant alloys. Test results were impressive, with the valve achieving five orders of magnitude better sealing leak rate over end of life requirements. Cycle life was equally impressive, achieving 280,000 cycles without failure.

  18. Public Release of Pan-STARRS Data

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather; Consortium, panstarrs

    2015-08-01

    Pan-STARRS 1 is a 1.8 meter survey telescope, located on Haleakala, Hawaii, with a 1.4 Gigapixel camera, a 7 square degree field of view, and 5 filters (g,r,i,z,y). The public release of data, which is available to everyone, consists of 4 years of data taken between May 2010 and April 2014. Two of the surveys available in the public release are the 3pi survey and the Medium Deep (MD) survey. The 3pi survey has roughly 60 epochs (12 per filter) covering 3/4 of the sky and everything north of -30 degrees declination. The MD survey consists of 10 fields, observed in a couple of filters each night, usually 8 exposures per filter per field, for about 4000 epochs per MD field. The available data product are accessed through the “Postage Stamp Server” and through the Published Science Products Subsystem (PSPS), both of these are available through the Pan-STARRS Science Interface (PSI). The Postage Stamp Server provides images and catalogs for different stages of processing on single exposures, stack images, difference images, and forced photometry. The PSPS is a SQLServer database that can be queried via script or web interface, with a database for each MD field and a large database for the 3pi survey. This database has relative photometry and astrometry and object associations, making it easy to do searches across the entire sky as well as tools to generate lightcurves of individual objects as a function of time.

  19. Long-term outcome of stapled transanal rectal resection (STARR) versus stapled hemorrhoidopexys (STH) for grade III-IV hemorrhoids: preliminary results.

    PubMed

    Zanella, Simone; Spirch, Saverio; Scarpa, Marco; Ricci, Francesco; Lumachi, Franco

    2014-01-01

    Circular stapled transanal hemorrhoidopexy (STH) was first introduced by A. Longo for the correction of internal mucosal prolapse and obstructed defecation and in 1998, was proposed as alternative to conventional excisional hemorrhoidectomy. More recently, stapled transanal rectal resection (STARR) has gradually gained popularity, as the Longo procedure, in the treatment of hemorrhoids. The aim of our study was to evaluate the usefulness of STARR as alternative to STH in patients with grade III (n=218, 68.1%) and IV (n=102, 31.9%) hemorrhoids. A group of 320 consecutive patients (median age=51 years; range=16-85) underwent STH (n=281) or STARR (n=39) procedure. The rate of postoperative bleeding (53.8% vs. 74.4%, p<0.01) was significantly reduced in patients who underwent STARR procedure, which required a longer (45 ± 22 vs. 26 ± 11 min, p<0.01) operative time. There were no differences between groups with regard to use of painkillers, postoperative pain intensity, short- (three months) and long-term (one and three years) residual pain, soiling, incontinence and urgency. Patients treated with the STARR procedure had lower recurrence rate of hemorrhoids and a lower incidence of prolapse, both at one year (none vs. 1.4%, p=0.593 and 2.6% vs. 5.3%, p=0.396, respectively) and at two years (none vs. 6.8%, p=0.078 and none vs. 13.2%, p=0.012, respectively). The one-year (9.0 ± 1.8 vs. 9.4 ± 0.7, p=0.171) and two-year (9.6 ± 0.8 vs. 9.1 ± 1.7, p=0.072) general satisfaction was similar but higher in STARR patients than in the STH group. In conclusion, according to our preliminary results, the STARR procedure leads to a lower incidence of complications and recurrences and should be considered for patients with grade III or IV hemorrhoids previously selected for stapled hemorrhoidectomy, as a promising alternative to STH. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  20. KEGS Discovery of 9 Supernova Candidates in the K2 Campaign 17 field with Pan-STARRS PS1

    NASA Astrophysics Data System (ADS)

    Smith, K. W.; Rest, A.; Tucker, B. E.; Garnavich, P. M.; Margheim, S.; Kasen, D.; Olling, R.; Shaya, E.; Narayan, G.; Villar, A.; Forster, F.; Mushotzky, R.; Zenteno, A.; James, D.; Smith, R. Chris; Dotson, J. L.; Barentsen, G.; Gully-Santiago, M.; Smartt, S. J.; Wright, D. E.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Schultz, A.; Magnier, E.; Waters, C.; Bulger, J.; Wainscoat, R. J.

    2018-05-01

    We report the following transients discovered by Pan-STARRS1 during a targeted search of the Kepler Campaign 17 field as part of the K2 Extragalactic Survey (KEGS) for Transients (see http://www.mso.anu.edu.au/kegs/ ) Information on the Pan-STARRS Survey for Transients is available at http://star.pst.qub.ac.uk/ps1threepi/ (see Huber et al. ATel #7153).

  1. Repeat transcatheter aortic valve implantation using a latest generation balloon-expandable device for treatment of failing transcatheter heart valves.

    PubMed

    Schaefer, Andreas; Treede, Hendrik; Seiffert, Moritz; Deuschl, Florian; Schofer, Niklas; Schneeberger, Yvonne; Blankenberg, Stefan; Reichenspurner, Hermann; Schaefer, Ulrich; Conradi, Lenard

    2016-01-15

    Paravalvular leakage (PVL) is a known complication of transcatheter aortic valve implantation (TAVI) and is associated with poor outcome. Besides balloon-post-dilatation, valve-in-valve (ViV) procedures can be taken into consideration to control this complication. Herein we present initial experience with use of the latest generation balloon-expandable Edwards Sapien 3® (S3) transcatheter heart valve (THV) for treatment of failing THVs. Between 01/2014 and 12/2014 three patients (two male, age: 71-80 y, log EUROScore I: 11.89 - 32.63) with failing THVs were refered to our institution for further treatment. THV approach with secondary implantation of an S3 was chosen after mutual agreement of the local interdisciplinary heart team at an interval of 533-1119 days from the index procedure. The performed procedures consisted of: S3 in Sapien XT, JenaValve and CoreValve. Successful transfemoral implantation with significant reduction of PVL was achieved in all cases. No intraprocedural complications occurred regarding placement of the S3 with a postprocedural effective orifice area (EOA) of 1.5-2.5 cm(2) and pressure gradients of max/mean 14/6-36/16 mmHg. 30-day mortality was 0%. At the latest follow-up of 90-530 days, all patients are alive and well with satisfactory THV function. Regarding VARC-2 criteria one major bleeding and one TIA was reported. In the instance of moderate or severe aortic regurgitation after TAVI, S3 ViV deployment is an excellent option to reduce residual regurgitation to none or mild. For further assertions concerning functional outcomes long-term results have to be awaited.

  2. Transcatheter heart valves for the treatment of aortic stenosis: state-of-the-art.

    PubMed

    Del Valle-Fernández, R; Ruiz, C E

    2008-10-01

    Degenerative aortic stenosis is the most frequent heart valve disease. As an alternative to surgical aortic valve replacement, several companies are working on the development of new prosthesis designed to be deployed by transcatheter approaches. Both transfemoral and transapical techniques are feasible, and initial trials in high-risk patients show good procedural outcomes and mid-term (up to 2 years) functionality. Two first-generation prosthesis (Edwards-SAPIEN and CoreValve Revalving System) are commercially available in Europe, and a number of other second-generation valves (with the capabilities of repositioning and retrievability) are under evaluation. Among them, the Sadra-Lotus Valve, The Direct Flow Medical valve and the Paniagua Heart Valve have published first-in-man results; the JenaValve and AorTx devices have also been temporarily implanted in humans. The development of repositionable and retrievable prosthesis with improved profile is mandatory, and it is the main focus of current projects. Not only technical improvements but also operators specialization and an optimal patient selection are essential to improve these initial Some procedural challenges need to be overcome prior to the expansion of these techniques to lower risk groups, and time is needed for detailed long-term outcomes and risk estimations. Only with a close collaboration among different specialists, basic researchers and the industry will the future development of transcatheter aortic implantation techniques be ensured.

  3. Results from the Pan-STARRS1 Sky Surveys

    NASA Astrophysics Data System (ADS)

    Chambers, Kenneth C.; PS1 Science Consortium

    2015-01-01

    Results from the Pan-STARRS1 Sky Surveys spanning the field of astronomy from Near Earth Objects to Cosmology will be presented.Scientific highlights from the PS1 Sky Surveys include: the photometric and astrometric reference catalog with unprecedented size, accuracy, and dynamic range discovery of 1200 NEO's, 120 PHAs, 60 comets; discovery of rotational break up as the origin of catastrophic disruption of solar system bodies; first free floating planet PSO 318-22 and other ultra-cool objects; first 3-dimensional map of dust in the Milky Way; new distances to molecular clouds; new stellar streams in the Milky Way and new globular clusters; new satellite galaxies of M31; eclipsing binaries in M31 - an important step for the distance ladder; micro-lensing events and other variables in M31: super-luminous and under-luminous stellar explosions; first clear tidal disruption of star by supermassive black hole; many new high redshift quasars; and a new determination of the dark energy equation of state from SnIa photometry.The nearly 4 year Pan-STARRS1 Science Mission has now completed. The reprocessing of the entire data set is underway. The Public Release of the entire image, catalog and metadata set of the PS1 Sky Surveys is scheduled for April 1, 2015 from the STScI MAST archive. It is expected that a great many more scientific results will come with community access to the data set.The Pan-STARRS1 Surveys have been made possible through contributions of the Institute for Astronomy of the University of Hawaii; the Max-Planck Society and its participating institutes: the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching; The Johns Hopkins University; Durham University; the University of Edinburgh; Queen's University Belfast; the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated; the National Central University of Taiwan; the Space Telescope

  4. Traditional Native American Ball Games in the Early 20th Century Recorded by Edward S. Curtis, Artist with a Camera.

    ERIC Educational Resources Information Center

    Pesavento, Wilma J.

    The work of Edward S. Curtis, who studied and recorded American Indian culture with a camera, is described in this paper. Curtis recorded on film, with explanatory text, a photo-history of eighty tribes west of the Missouri River. The role of games and their accompanying mythology was one of the salient features of Curtis's work. The general…

  5. [Prevention of post-operative pain and haemorrhage in PPH (Procedure for Prolapse and Hemorrhoids) and STARR (Stapled Trans-Anal Rectal Resection). Preliminary results in 261 cases].

    PubMed

    Mongardini, M; Custureri, F; Schillaci, F; Cola, A; Maturo, A; Fanello, G; Corelli, S; Pappalardo, G

    2005-04-01

    Intra- and early (first week) post-operative haemorrhages are the most common complications in stapled hemorrhoidectomy PPH (Procedure for Prolapse and Hemorrhoids) and in circumferential resection of the rectal prolapse STARR (Stapled Trans Anal Rectal Resection). Performing PPH and STARR we employed a gelatin based haemostatic sealant with thrombin component (FloSeal) to control intra-operative bleeding and to reduce post-operative bleeding avoiding haemostatic stitches on suture line. We report the preliminary results on 197 PPH and 64 STARR; 44 PPH (22.4%) and 27 STARR (42.2%) were treated by FloSeal. No major post-operative bleeding was observed in all patients treated by FloSeal, compared to 1.3% and 2.7% of hemorrhage respectively in PPH and STARR patients treated without sealant. Post-operative pain was less severe in patients treated by FloSeal, without a difference statistically significant. The data are preliminary and must be confirmed in prospective randomized trials in larger series.

  6. The economic value of rapid deployment aortic valve replacement via full sternotomy.

    PubMed

    Moore, Matt; Barnhart, Glenn R; Chitwood, W Randolph; Rizzo, John A; Gunnarsson, Candace; Palli, Swetha R; Grossi, Eugene A

    2017-06-01

    To compare the economic value of EDWARDS INTUITY Elite™ (EIE) valve system for rapid-deployment aortic valve replacement (RDAVR) in a full sternotomy (FS) approach (EIE-FS-RDAVR) versus FS-AVR using conventional stented bioprosthesis. A simulation model to compare each treatment's 30-day inpatient utilization and complication rates utilized: clinical end points obtained from the TRANSFORM trial patient subset (EIE-FS-RDAVR) and a best evidence review of the published literature (FS-AVR); and costs from the Premier database and published literature. EIE-FS-RDAVR costs $800 less than FS-AVR per surgery episode attributable to lowered complication rates and utilization. Combined with the lower mortality, EIE-FS-RDAVR was a superior (dominant) technology versus FS-AVR. This preliminary investigation of EIE-FS-RDAVR versus conventional FS-AVR found the EIE valve offered superior economic value over a 30-day period. Real-world analyses with additional long-term follow-up are needed to evaluate if this result can be replicated over a longer timeframe.

  7. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2001-01-01

    Part of the 2000 annual review of the industrial minerals sector. A general overview of the ball clay industry is provided. In 2000, sales of ball clay reached record levels, with sanitary ware and tile applications accounting for the largest sales. Ball clay production, consumption, prices, foreign trade, and industry news are summarized. The outlook for the ball clay industry is also outlined.

  8. The Pan-STARRS pipeline and data products

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather

    2018-01-01

    I will give a brief overview of the pipeline, database, and dataproducts for Pan-STARRS1 data release 1 (DR1) and data release 2 (DR2). DR1 and DR2 provides access to data from the Pan-STARRS1 3pi survey, a survey which covers ¾ of the sky over 4 years (2010-2014), everything with a declination greater than -30, in 5 filters (g,r,i,z,y), with at least 12 epochs per filter per area of sky. DR1, released in December 2016, and available to the public at http://stsci.panstarrs.edu, consists of two parts: the stacked images with a 5 sigma depth of (23.3,23.2,23.1,22.3,21.3) for (g,r,i,z,y), and the catalog database, which consists of 10 billion distinct objects, their mean properties from single exposures, and stack photometry. DR2, to be released early 2108, will contain the individual exposure images, with a 5 sigma depth of (22.0,21.8,21.5,20.9,19.7) for (g,r,i,z,y), and the time domain catalogs, from the 374k individual exposures taken for the 3pi survey. I will primarily focus on the catalog database, describing a subset of the tables and different use cases for them. Specifically, I will describe the major tables and metadata of DR1 - objects, their mean properties, and stack photometry, when different tables should be used, and basics on how to filter the data.

  9. Balloon expandable transcatheter aortic valve implantation with or without pre-dilation of the aortic valve - rationale and design of a multicenter registry (EASE-IT).

    PubMed

    Bramlage, Peter; Strauch, Justus; Schröfel, Holger

    2014-11-18

    In patients with severe calcific aortic stenosis, balloon aortic valvuloplasty (BAV) is routinely performed in order to pre-dilate the stenosed aortic valve prior to transcatheter aortic valve implantation (TAVI). Although pre-dilation is considered to be essential for the preparation of the valve landing zone, there is no clear evidence to support its clinical value. In contrast, BAV has been suggested to be linked to several complications. Notably, while preliminary evidence has supported the feasibility and safety of TAVI without pre-dilation, larger studies directly comparing the benefit/risk profile of TAVI in the presence and absence of pre-dilation are required. Therefore, a prospective, two-armed, multicenter registry (EASE-IT) was designed to obtain essential data concerning procedural success rates, adverse events, and mortality in a large cohort of patients undergoing transapical (TA)-TAVI using the Edwards SAPIEN 3 balloon expandable heart valves with and without pre-ballooning. Data provided by EASE-IT will be used to assess the relevance of BAV during the TAVI procedure and to investigate associations between patient characteristics and outcomes. Therefore, results obtained from the EASE-IT registry could contribute to reduced rates of TAVI-associated morbidity and mortality in patients with severe, calcific aortic stenosis. ClinicalTrials.gov Identifier: NCT02127580.

  10. Mitral Valve Stenosis after Open Repair Surgery for Non-rheumatic Mitral Valve Regurgitation: A Review.

    PubMed

    Shabsigh, Muhammad; Lawrence, Cassidy; Rosero-Britton, Byron R; Kumar, Nicolas; Kimura, Satoshi; Durda, Michael Andrew; Essandoh, Michael

    2016-01-01

    Mitral stenosis (MS) after mitral valve (MV) repair is a slowly progressive condition, usually detected many years after the index MV surgery. It is defined as a mean transmitral pressure gradient (TMPG) >5 mmHg or a mitral valve area (MVA) <1.5 cm(2). Pannus formation around the mitral annulus or extending to the mitral leaflets is suggested as the main mechanism for developing delayed MS after MV repair. On the other hand, early stenosis is thought to be a direct result of an undersized annuloplasty ring. Furthermore, in MS following ischemic mitral regurgitation (MR) repair, subvalvular tethering is the hypothesized pathophysiology. MS after MV repair has an incidence of 9-54%. Several factors have been associated with a higher risk for developing MS after MV repair, including the use of flexible Duran annuloplasty rings versus rigid Carpentier-Edwards rings, complete annuloplasty rings versus partial bands, small versus large anterior leaflet opening angle, and anterior leaflet tip opening length. Intraoperative echocardiography can measure the anterior leaflet opening angle, the anterior leaflet tip opening dimension, the MVA and the mean TMPG, and may help identify patients at risk for developing MS after MV repair.

  11. Mitral Valve Stenosis after Open Repair Surgery for Non-rheumatic Mitral Valve Regurgitation: A Review

    PubMed Central

    Shabsigh, Muhammad; Lawrence, Cassidy; Rosero-Britton, Byron R.; Kumar, Nicolas; Kimura, Satoshi; Durda, Michael Andrew; Essandoh, Michael

    2016-01-01

    Mitral stenosis (MS) after mitral valve (MV) repair is a slowly progressive condition, usually detected many years after the index MV surgery. It is defined as a mean transmitral pressure gradient (TMPG) >5 mmHg or a mitral valve area (MVA) <1.5 cm2. Pannus formation around the mitral annulus or extending to the mitral leaflets is suggested as the main mechanism for developing delayed MS after MV repair. On the other hand, early stenosis is thought to be a direct result of an undersized annuloplasty ring. Furthermore, in MS following ischemic mitral regurgitation (MR) repair, subvalvular tethering is the hypothesized pathophysiology. MS after MV repair has an incidence of 9–54%. Several factors have been associated with a higher risk for developing MS after MV repair, including the use of flexible Duran annuloplasty rings versus rigid Carpentier–Edwards rings, complete annuloplasty rings versus partial bands, small versus large anterior leaflet opening angle, and anterior leaflet tip opening length. Intraoperative echocardiography can measure the anterior leaflet opening angle, the anterior leaflet tip opening dimension, the MVA and the mean TMPG, and may help identify patients at risk for developing MS after MV repair. PMID:27148540

  12. Association of aortic valve calcification severity with the degree of aortic regurgitation after transcatheter aortic valve implantation.

    PubMed

    Koos, Ralf; Mahnken, Andreas Horst; Dohmen, Guido; Brehmer, Kathrin; Günther, Rolf W; Autschbach, Rüdiger; Marx, Nikolaus; Hoffmann, Rainer

    2011-07-15

    This study sought to examine a possible relationship between the severity of aortic valve calcification (AVC), the distribution of AVC and the degree of aortic valve regurgitation (AR) after transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS). 57 patients (22 men, 81 ± 5 years) with symptomatic AS and with a logistic EuroSCORE of 24 ± 12 were included. 38 patients (67%) received a third (18F)-generation CoreValve® aortic valve prosthesis, in 19 patients (33%) an Edwards SAPIEN™ prosthesis was implanted. Prior to TAVI dual-source computed tomography for assessment of AVC was performed. To determine the distribution of AVC the percentage of the calcium load of the most severely calcified cusp was calculated. After TAVI the degree of AR was determined by angiography and echocardiography. The severity of AR after TAVI was related to the severity and distribution of AVC. There was no association between the distribution of AVC and the degree of paravalvular AR after TAVI as assessed by angiography (r = -0.02, p = 0.88). Agatston AVC scores were significantly higher in patients with AR grade ≥ 3 (5055 ± 1753, n = 3) than in patients with AR grade < 3 (1723 ± 967, p = 0.03, n = 54). Agatston AVC scores > 3000 were associated with a relevant paravalvular AR and showed a trend for increased need for second manoeuvres. There was a significant correlation between the severity of AVC and the degree of AR after AVR (r = 0.50, p < 0.001). Patients with severe AVC have an increased risk for a relevant AR after TAVI as well as a trend for increased need for additional procedures. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  13. Traumatic rupture of the tricuspid valve and multi-modality imaging

    PubMed Central

    Corneli, Mariana; Conde, Diego; Ronderos, Ricardo

    2014-01-01

    Introduction Motor vehicle accident (MVA) account for most cases of traumatic rupture of the tricuspid valve. Valve rupture during an MVA is generated by an abrupt deceleration coupled with an increase in right-side cardiac pressures (Valsalva maneuver and thorax compression). Case A 39-year-old asymptomatic man was referred for an echocardiogram due to the presence of a systolic murmur. He had no prior significant medical history, except for a remote MVA 3 years ago. Real-time 3D echocardiography (RT3DE) showed a tear in the body of the anterior leaflet and not at the cord, as was suggested by two-dimensional transthoracic echocardiography (2D-TTE). Based on these findings, the mechanism was considered anterior leaflet rupture of the tricuspid valve, secondary to chest blunt trauma. The anterior leaflet was repaired using two polytetrafluoroethylene sutures, and tricuspid annuloplasty with an Edwards ring was performed. Conclusions Multimodality imaging helps to determine timing of surgery in asymptomatic traumatic tricuspid rupture. The combination of echocardiography and magnetic resonance imaging provide information of volumetric data and contractility of the right ventricle (RV) during follow-up. RT3DE gives information relevant to the morphological and functional characterization of the valve, allowing the planning of appropriate surgical procedure. PMID:25414827

  14. The Pan-STARRS 1 Medium Deep Field Variable Star Catalog

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather

    2015-01-01

    We present the first Pan-STARRS 1 Medium Deep Field Variable Star Catalog (PS1-MDF-VSC). The Pan-STARRS 1 (PS1) telescope is a 1.8 meter survey telescope with a 1.4 Gigapixel camera, located in Haleakala, Hawaii. The Medium Deep survey, which consists of 10 fields located uniformly across the sky, totalling 70 square degrees, is observed each night, in 2-3 filters per field, with 8 exposures per filter, resulting in 3000-4000 data points per star over a time span of 3.5 years. To find the variables, we select the stars with > 200 detections, between 16th and 21st magnitude. There are approximately 500k stars that fit this criteria, they then go through a lomb-scargle fitting routine to determine periodicity. After a periodicity cut, the ~400 candidates are classified by eye into different types of variable stars. We have identified several hundred variable stars, with periods ranging between a few minutes to a few days, and about half are not previously identified in the literature. We compare our results to the stripe 82 variable catalog, which overlaps part of the sky with the PS1 catalog.

  15. The Pan-STARRS 1 Medium Deep Field Variable Star Catalog

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather

    2015-08-01

    We present the first Pan-STARRS 1 Medium Deep Field Variable Star Catalog (PS1-MDF-VSC). The Pan-STARRS 1 (PS1) telescope is a 1.8 meter survey telescope with a 1.4 Gigapixel camera, located in Haleakala, Hawaii. The Medium Deep survey, which consists of 10 fields located uniformly across the sky, totalling 70 square degrees, is observed each night, in 2-3 filters per field, with 8 exposures per filter, resulting in 3000-4000 data points per star over a time span of 3.5 years. To find the variables, we select the stars with > 200 detections, between 16th and 21st magnitude. There are approximately 500k stars that fit this criteria, they then go through a lomb-scargle fitting routine to determine periodicity. After a periodicity cut, the ~400 candidates are classified by eye into different types of variable stars. We have identified several hundred variable stars, with periods ranging between a few minutes to a few days, and about half are not previously identified in the literature. We compare our results to the stripe 82 variable catalog, which overlaps part of the sky with the PS1 catalog.

  16. Reexamination of Ball-Race Conformity Effects on Ball Bearing Life

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.; Poplawski, Joseph V.; Root, Lawrence E.

    2007-01-01

    The analysis in this report considers the life of the ball set as well as the respective lives of the races to reassess the effect of ball-race conformity on ball bearing life. The related changes in ball bearing life are incorporated in life factors that can be used to modify the bearing predicted life using the Lundberg-Palmgren equations and the ANSI/ABMA and ISO Standards. Two simple algebraic relationships were established to calculate life factors LF(sub c) to determine the effect of inner- and outer-race conformity combinations on bearing L(sub 10) life for deepgroove and angular-contact ball bearings, respectively. Depending on the bearing type and series as well as conformity combinations, the calculated life for deep-groove ball bearings can be over 40 percent less than that calculated by the Lundberg-Palmgren equations. For angular-contact ball bearings, the life can vary between +16 and -39 percent from that calculated by the Lundberg-Palmgren equations. Comparing the two ball bearing types, the life factors LF(sub c) for the deep-groove bearings can be as much as 40 percent lower than that for angular-contact ball bearings.

  17. Design of the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS)

    PubMed Central

    Kessler, Ronald C.; Colpe, Lisa J.; Fullerton, Carol S.; Gebler, Nancy; Naifeh, James A.; Nock, Matthew K.; Sampson, Nancy A.; Schoenbaum, Michael; Zaslavsky, Alan M.; Stein, Murray B.; Ursano, Robert J.; Heeringa, Steven G.

    2014-01-01

    The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) is a multi-component epidemiological and neurobiological study designed to generate actionable evidence-based recommendations to reduce U.S. Army suicides and increase basic knowledge about the determinants of suicidality. This report presents an overview of the designs of the six component Army STARRS studies. These include: an integrated study of historical administrative data systems (HADS) designed to provide data on significant administrative predictors of suicides among the more than 1.6 million soldiers on active duty in 2004–2009; retrospective case-control studies of suicide attempts and fatalities; separate large-scale cross-sectional studies of new soldiers (i.e., those just beginning Basic Combat Training [BCT], who completed self-administered questionnaires [SAQ] and neurocognitive tests and provided blood samples) and soldiers exclusive of those in BCT (who completed SAQs); a pre-post deployment study of soldiers in three Brigade Combat Teams about to deploy to Afghanistan (who completed SAQs and provided blood samples) followed multiple times after returning from deployment; and a platform for following up Army STARRS participants who have returned to civilian life. DoD/Army administrative data records are linked with SAQ data to examine prospective associations between self-reports and subsequent suicidality. The presentation closes with a discussion of the methodological advantages of cross-component coordination. PMID:24318217

  18. Complications of the access during aortic valve implantation through transfemoral access.

    PubMed

    Alsac, Jean-Marc; Zegdi, Rachid; Blanchard, Didier; Achouh, Paul; Cholley, Bernard; Berrebi, Alain; Julia, Pierre; Fabiani, Jean-Noël

    2011-08-01

    Aortic valve implantation (AVI) is a booming therapeutic option in high-risk patients with calcific aortic stenosis. Retrograde femoral approach drawbacks include vascular complications owing to the size of the introduction system (22- and 24-F).The aim of this study was to retrospectively analyze the incidence and the treatment of vascular complications in the first 2 years of transfemoral AVI experience with the first generation of Edwards SAPIEN transcatheter heart valves. Since December 2007, AVI has been performed in 71 patients, 21 times by the transapical route and 50 times by the transfemoral route through an inguinal approach with the first generation of Edwards SAPIEN transcatheter heart valves (23 and 26 mm). The incidence and the treatment of vascular complications were evaluated as main criteria for transfemoral AVI. All the procedures could be successfully performed by a femoral route, except for three cases when the introducing device could not be fixed on the thoracic aorta because of vascular access problems. Vascular access-related complications occurred in nine patients (18%), including three iliac dissections, two aortic dissections, three femoral lesions, and one thoracic aorta rupture. These complications were treated either in a conservative way (n = 2), or in an endovascular way using a contralateral approach (n = 3), or surgically through an inguinal approach (n = 3). A traumatic rupture of the thoracic aorta resulted in the death of a female patient. In our experience, transfemoral AVI gives a satisfying technical success rate in the selected patients. The incidence of complications involving the vascular access remains an important limitation of this new technique. Although a conservative or endovascular treatment can be applied in most cases, improving the introduction devices is highly expected because it would reduce the complications rate of vascular access. Copyright © 2011 Annals of Vascular Surgery Inc. Published by Elsevier Inc

  19. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2013-01-01

    Four companies — H.C. Spinks Clay Co., Inc., Imerys, Old Hickory Clay Co. and Unimin Corp. — mined ball clay in five U.S. states in 2012. Production, on the basis of preliminary data, was 900 kt (992,000 st), with an estimated value of $42.3 million. This was a slight increase in tonnage from 886 kt (977,000 st), with a value of $40.9 million in 2011. Tennessee was the leading ball clay producing state, with 63 percent of domestic production, followed by Texas, Mississippi, Kentucky and Indiana. Reported ball clay production from Indiana probably was fire clay rather than ball clay. About 69 percent of total ball clay production was airfloat, 20 percent was crude and 11 percent was water-slurried.

  20. Discovery of Main-Belt Comet P/2006 VW139 by Pan-STARRS1

    NASA Astrophysics Data System (ADS)

    Hsieh, H. H.; Yang, B.; Haghighipour, N.; Kaluna, H. M.; Fitzsimmons, A.; Denneau, L.; Novakovic, B.; Jedicke, R.; Wainscoat, R. J.; Armstrong, J. D.; Duddy, S. R.; Lowry, S. C.; Trujillo, C. A.; Micheli, M.; Keane, J. V.; Urban, L.; Riesen, T.; Meech, K. J.; Abe, S.; Cheng, Y. C.; Chen, W. P.; Granvik, M.; Grav, T.; Ip, W. H.; Kinoshita, D.; Kleyna, J.; Lacerda, P.; Lister, T.; Milani, A.; Tholen, D. J.; Veres, P.; Lisse, C. M.; Kelley, M. S.; Fernandez, Y. R.; Bhatt, B. C.; Sahu, D. K.; Kaiser, N.; Chambers, K. C.; Hodapp, K. W.; Magnier, E. A.; Price, P. A.; Tonry, J. L.

    2012-05-01

    We describe the discovery of comet-like activity in main-belt asteroid (300163) 2006 VW139 (later re-designated as Comet P/2006 VW139) by Pan-STARRS1. We also detail follow-up photometric, spectroscopic, and dynamical analyses of the object.

  1. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2000-01-01

    Part of the 1999 Industrial Minerals Review. The state of the ball clay industry in 1999 is presented. Record highs in the sales and use of ball clay were attained in 1999 due to the continued strength of the U.S. economy. U.S. production was estimated at 1.25 million st for the year, with more than half of that amount mined in Tennessee. Details of the consumption, price, imports, and exports of ball clay in 1999 and the outlook for ball clay over the next few years are provided.

  2. Sky-plane discovery rates for Near Earth Object discoveries from Pan-STARRS1 - implications for future search strategies

    NASA Astrophysics Data System (ADS)

    Wainscoat, Richard J.; Chambers, Kenneth C.; Chastel, Serge; Denneau, Larry; Lilly Schunova, Eva; Micheli, Marco; Weryk, Robert J.

    2016-10-01

    The Pan-STARRS1 telescope has been spending most of its time for the last 2.5 years searching the sky for Near Earth Objects (NEOs). The surveyed area covers the entire northern sky and extends south to -49 degrees declination. Because Pan-STARRS1 has a large field-of-view, it has been able survey large areas of the sky, and we are now able to examine NEO discovery rates relative to ecliptic latitude.Most contemporary searches, including Pan-STARRS1, have been spending large amounts of their observing time during the dark moon period searching for NEOs close to the ecliptic. The rationale for this is that many objects have low inclination, and all objects in orbit around the Sun must cross the ecliptic. New search capabilities are now available, including Pan-STARRS2, and the upgraded camera in Catalina Sky Survey's G96 telescope. These allow NEO searches to be conducted over wider areas of the sky, and to extend further from the ecliptic.We have examined the discovery rates relative to location on the sky for new NEOs from Pan-STARRS1, and find that the new NEO discoveries are less concentrated on the ecliptic than might be expected. This finding also holds for larger objects. The southern sky has proven to be very productive in new NEO discoveries - this is a direct consequence of the major NEO surveys being located in the northern hemisphere.Our preliminary findings suggest that NEO searches should extend to at least 30 degrees from the ecliptic during the more sensitive dark moon period. At least 6,000 deg2 should therefore be searched each lunation. This is possible with the newly augmented NEO search assets, and repeat coverage will be needed in order to recover most of the NEO candidates found. However, weather challenges will likely make full and repeated coverage of such a large area of sky difficult to achieve. Some simple coordination between observing sites will likely lead to improvement in efficiency.

  3. The valve choice in tricuspid valve replacement: 25 years of experience.

    PubMed

    Van Nooten, G J; Caes, F L; François, K J; Taeymans, Y; Primo, G; Wellens, F; Leclerq, J L; Deuvaert, F E

    1995-01-01

    This study reviews 146 consecutive patients who underwent tricuspid valve replacement (TVR) with 69 bioprostheses (porcine and bovine pericardial) and 77 mechanical ball, disc or bileaflet valves between 1967 and 1987. The mean age was 51.4 +/- 12.1 years. Preoperatively, 97% were in New York Heart Association (NYHA) functional class III or more and over 40% had undergone previous cardiac surgery. Hospital mortality was high (16.1%). Incremental risk factors for hospital death were preoperative icterus (P < 0.01), hepatomegaly (P = 0.02), NYHA functional class IV (P = 0.02) and male sex (P = 0.04) (univariate analysis). Ninety-eight percent of the hospital survivors were followed up for a mean of 92 months. Cumulative follow-up added up to 955 patient-years. There were 70 late deaths. The actuarial survival rate was 74% at 60 months and less than 25% at 14 years. Incremental risk factors for late death indicated by univariate analysis were the type of tricuspid prosthesis (Smel-off-Cutter and Kay-Shiley prostheses) (P = 0.04), the type of operative myocardial protection (normothermia and coronary perfusion) (P = 0.05) and preoperative NYHA functional class IV (P = 0.05). We conclude that TVR carries a high operative risk and poor long-term survival, both influenced by preoperative and perioperative variables. Bearing in mind the poor prognosis for TVR, we prefer a large-sized bioprosthesis, in view of its initial good durability and low risk of valve-related events. However, in patients with good life expectancy, a bileaflet mechanical prosthesis may be an acceptable alternative.

  4. Design of the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS).

    PubMed

    Kessler, Ronald C; Colpe, Lisa J; Fullerton, Carol S; Gebler, Nancy; Naifeh, James A; Nock, Matthew K; Sampson, Nancy A; Schoenbaum, Michael; Zaslavsky, Alan M; Stein, Murray B; Ursano, Robert J; Heeringa, Steven G

    2013-12-01

    The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) is a multi-component epidemiological and neurobiological study designed to generate actionable evidence-based recommendations to reduce US Army suicides and increase basic knowledge about the determinants of suicidality. This report presents an overview of the designs of the six components of the Army STARRS. These include: an integrated analysis of the Historical Administrative Data Study (HADS) designed to provide data on significant administrative predictors of suicides among the more than 1.6 million soldiers on active duty in 2004-2009; retrospective case-control studies of suicide attempts and fatalities; separate large-scale cross-sectional studies of new soldiers (i.e. those just beginning Basic Combat Training [BCT], who completed self-administered questionnaires [SAQs] and neurocognitive tests and provided blood samples) and soldiers exclusive of those in BCT (who completed SAQs); a pre-post deployment study of soldiers in three Brigade Combat Teams about to deploy to Afghanistan (who completed SAQs and provided blood samples) followed multiple times after returning from deployment; and a platform for following up Army STARRS participants who have returned to civilian life. Department of Defense/Army administrative data records are linked with SAQ data to examine prospective associations between self-reports and subsequent suicidality. The presentation closes with a discussion of the methodological advantages of cross-component coordination. Copyright © 2013 John Wiley & Sons, Ltd.

  5. Ball clay

    USGS Publications Warehouse

    Virta, Robert L.

    2010-01-01

    The article reports on the global market performance of ball clay in 2009 and presents an outlook for its 2010 performance. Several companies mined ball call in the country including Old Hickey Clay Co., Kentucky-Tennessee Clay Co., and H.C. Spinks Clay Co. Information on the decline in ball clay imports and exports is also presented.

  6. Having a Ball with Fitness Balls

    ERIC Educational Resources Information Center

    McNulty, Betty

    2011-01-01

    Fitness programs can be greatly enhanced with the addition of fitness balls. They are a fun, challenging, economical, and safe way to incorporate a cardiovascular, strength, and stretching program for all fitness levels in a physical education setting. The use of these balls has become more popular during the last decade, and their benefits and…

  7. One-year multicentre outcomes of transapical aortic valve implantation using the SAPIEN XT™ valve: the PREVAIL transapical study.

    PubMed

    Walther, Thomas; Thielmann, Matthias; Kempfert, Joerg; Schroefel, Holger; Wimmer-Greinecker, Gerhard; Treede, Hendrik; Wahlers, Thorsten; Wendler, Olaf

    2013-05-01

    The study aimed to evaluate 1-year outcomes of the multicentre PREVAIL transapical (TA) study of TA-aortic valve implantation (AVI) in high-risk patients. From September 2009 to August 2010, a total of 150 patients, aged 81.6 ± 5.8 years, 40.7% female, were included at 12 European TA-AVI experienced sites. Patients received 23 (n = 36), 26 (n = 57) and 29 mm (n = 57) second-generation SAPIEN XT™ (Edwards Lifesciences, Irvine, CA, USA) valves. The mean logistic EuroSCORE was 24.3 ± 7.0, and mean Society Thoracic Surgeons score was 7.5 ± 4.4%. Survival was 91.3% at 30 days and 77.9% at 1 year. Subgroup analysis revealed survivals of 91.7/88.9, 86.0/70.2, 96.55/91.2% for patients receiving 23-, 26- and 29-mm valves at 30 days and at 1 year, respectively. Transthoracic echocardiography revealed preserved left ventricular ejection fraction and low gradients. Aortic incompetence was none in 41/48, trace 30/36, mild 22/12 and moderate in 7/4% at discharge and 1 year. Walking distance increased from 221 (postimplant) to 284 m (at 1 year, P = 0.0004). Three patients required reoperation due to increasing aortic incompetence during follow-up. Causes of mortality at 1 year were cardiac (n = 7), stroke (n = 1) and others (n = 5). The European PREVAIL multicentre trial demonstrates good functionality and good outcomes for TA-AVI using the second-generation SAPIEN XT prosthesis and the ASCENDRA-II delivery system. The 29-mm SAPIEN XT valve was successfully introduced and showed excellent results.

  8. Pilot Edwards reads a rendezvous timeline

    NASA Image and Video Library

    1998-03-03

    STS089-385-004 (22-31 Jan. 1998) --- Astronaut Joe F. Edwards Jr., STS-89 pilot, highlights important data on a checklist while temporarily occupying the commander's station on the port side of the space shuttle Endeavour's flight deck. Edwards, making his first spaceflight, is an alumnus of the 1995 class of astronaut candidates (ASCAN). Photo credit: NASA

  9. Early outcomes of transcatheter aortic valve replacement in patients with severe aortic stenosis: single center experience

    PubMed Central

    Bozkurt, Engin; Keleş, Telat; Durmaz, Tahir; Akçay, Murat; Ayhan, Hüseyin; Bayram, Nihal Akar; Aslan, Abdullah Nabi; Baştuğ, Serdal; Bilen, Emine

    2014-01-01

    Introduction Transcatheter aortic valve implantation is a promising alternative to high risk surgical aortic valve replacement. The procedure is mainly indicated in patients with severe symptomatic aortic stenosis who cannot undergo surgery or who are at very high surgical risk. Aim Description early results of our single-center experience with balloon expandable aortic valve implantation. Material and methods Between July 2011 and August 2012, we screened in total 75 consecutive patients with severe aortic stenosis and high risk for surgery. Twenty-one of them were found ineligible for transcatheter aortic valve implantation (TAVI) because of various reasons, and finally we treated a total of 54 patients with symptomatic severe aortic stenosis (AS) who could not be treated by open heart surgery (inoperable) because of high-risk criteria. The average age of the patients was 77.4 ±7.1; 27.8% were male and 72.2% were female. The number of patients in NYHA class II was 7 while the number of patients in class III and class IV was 47. Results The average mortality score of patients according to the STS scoring system was 8.5%. Pre-implantation mean and maximal aortic valve gradients were measured as 53.2 ±14.1 mm Hg and 85.5 ±18.9 mm Hg, respectively. Post-implantation mean and maximal aortic valve gradients were 9.0 ±3.0 and 18.2 ±5.6, respectively (p < 0.0001). The left ventricular ejection fraction was calculated as 54.7 ±14.4% before the operation and 58.0 ±11.1% after the operation (p < 0.0001). The duration of discharge after the operation was 5.29 days, and a statistically significant correlation between the duration of discharge after the operation and STS was found (r = 0385, p = 0.004). Conclusions We consider that with decreasing cost and increasing treatment experience, TAVI will be used more frequently in broader indications. Our experience with TAVI using the Edwards-Sapien XT (Edwards Lifesciences, Irvine, CA) devices suggests that this is an

  10. Trans-apical aortic valve implantation in patients with severe calcification of the ascending aorta.

    PubMed

    Buz, Semih; Pasic, Miralem; Unbehaun, Axel; Drews, Thorsten; Dreysse, Stephan; Kukucka, Marian; Mladenow, Alexander; Hetzer, Roland

    2011-08-01

    In patients with calcification of the ascending aorta, postoperative stroke and mortality rates remain high after conventional aortic valve replacement, but the results of trans-apical aortic valve implantation in these patients are not known. We evaluate the outcome of trans-apical aortic valve implantation in patients with severely calcified ascending aorta in a single center with expanded procedural experience. Between April 2008 and July 2010, 258 patients underwent trans-apical aortic valve implantation using Edwards Sapien valve. By computed tomography (CT) scan, we identified 46 (18%) patients with severe calcification of the ascending aorta (16 with porcelain aorta and 30 with severe, but not complete, calcification). Of 46 patients (mean age 77 ± 10 years, range 63-90 years; EuroSCORE (European System for Cardiac Operative Risk Evaluation) 45 ± 22%; STS (Society of Thoracic Surgeons) score 23 ± 13) with calcified aorta, 15 received 23-mm valves and 31 patients 26-mm valves. Primary valve implantation was successful in 44 patients and a second valve was implanted (valve-in-valve) in two. Six patients underwent concomitant interventions (three elective percutaneous coronary intervention (PCI), one off-pump coronary artery bypass (OPCAB), one tricuspid valve reconstruction, and one left-ventricular (LV) aneurysmectomy). The final procedural results showed valve incompetence (trace or grade 1) in 17 (37%) patients and paravalvular leak in 15 (32.6%) (trace in 10 and grade 1 in five). There was no 30-day mortality. Postoperatively, cranial CT showed new cerebral ischemia areas in three patients (6.2%), but only one patient (2.1%) experienced postoperative neurological deficit (temporary aphasia). Survival at 6 and 12 months was 88% and 85.2%, respectively. Trans-apical aortic valve implantation can be performed safely in patients with aortic valve stenosis and severe calcification of the ascending aorta. Copyright © 2010 European Association for Cardio

  11. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2011-01-01

    The article discusses the latest developments in the global ball clay mining industry, particularly in the U.S., as of June 2011. It cites several firms that are involved in ball clay mining in the U.S., including HC Spins Clay Co. Inc., the Imerys Group and Old Hickory Clay Co. Among the products made from ball clay are ceramic tiles, sanitaryware, as well as fillers, extenders and binders.

  12. Ball Machine Usage in Tennis: Movement Initiation and Swing Timing While Returning Balls from a Ball Machine and from a Real Server

    PubMed Central

    Carboch, Jan; Süss, Vladimir; Kocib, Tomas

    2014-01-01

    Practicing with the use of a ball machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a ball projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a ball machine or by a real server). Receivers’ movements were measured on a tennis court. In spite of using a serving ball speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a ball machine and serves received from a real server. Players had shorter movement initiation when they faced a ball machine. Backswing duration was longer for the group using a ball machine. That demonstrates different movement timing of tennis returns when players face a ball machine. Use of ball machines in tennis practice should be limited as it may disrupt stroke timing. Key points Players have shorter initial move time when they are facing the ball machine. Using the ball machine results in different swing timing and movement coordination. The use of the ball machine should be limited. PMID:24790483

  13. Ball machine usage in tennis: movement initiation and swing timing while returning balls from a ball machine and from a real server.

    PubMed

    Carboch, Jan; Süss, Vladimir; Kocib, Tomas

    2014-05-01

    Practicing with the use of a ball machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a ball projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a ball machine or by a real server). Receivers' movements were measured on a tennis court. In spite of using a serving ball speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a ball machine and serves received from a real server. Players had shorter movement initiation when they faced a ball machine. Backswing duration was longer for the group using a ball machine. That demonstrates different movement timing of tennis returns when players face a ball machine. Use of ball machines in tennis practice should be limited as it may disrupt stroke timing. Key pointsPlayers have shorter initial move time when they are facing the ball machine.Using the ball machine results in different swing timing and movement coordination.The use of the ball machine should be limited.

  14. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall be...

  15. Testing solar system formation models using Pan-STARRS1 detections of nearly inactive Manx comets

    NASA Astrophysics Data System (ADS)

    Boe, Benjamin; Jedicke, Robert; Meech, Karen Jean; Morbidelli, Alessandro; Wiegert, Paul

    2016-10-01

    Newly discovered Manx comets show low levels of sublimation at perihelion indicating significantly lower volatile abundance compared to typical long period comets. The S-class spectrum of Manx comet C/2014 S3 (PANSTARRS) indicates that they may have formed in the inner solar system and were later perturbed to the highly eccentric orbits observed today (Meech et al. 2016). We used the Pan-STARRS1 observation history and its Moving Object Processing System (MOPS) (Denneau et al. 2013) to model Manx detections since Pan-STARRS has been the primary discovery source of Manx comets. A synthetic Manx population was generated according to the Wiegert and Tremaine (1999) model and processed through MOPS to determine the expected Pan-STARRS1 detections and the corresponding detection efficiencies for Manx comets as a function of each orbital parameter and object size. The population of normal long period comets (LPCs) was modeled in the same fashion. Unbiased populations for LPCs and Manx comets were computed by correcting the real comet populations with the detection efficiencies. Finally, the ratio of the bias corrected number of Manx comets to LPCs is compared to the predictions of various solar system formation models.References:Meech, K. J. et al. (2016), Science Advances 2, 4, id. E1600038.Denneau, L. et al. (2013), Publications of the Astronomical Society of the Pacific, 125, 926, 357-395Wiegert, P. and Tremaine, S. (1999), Icarus, 137, 1, 84-121.

  16. The Pan-STARRS 1 Medium Deep Field Variable Star Catalog

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather

    2016-01-01

    We present the first Pan-STARRS 1 Medium Deep Field Variable Star Catalog (PS1-MDF-VSC). The Pan-STARRS 1 (PS1) telescope is a 1.8 meter survey telescope with a 1.4 Gigapixel camera, located in Haleakala, Hawaii. The Medium Deep survey, which consists of 10 fields located uniformly across the sky, totaling 70 square degrees, is observed each night, in 2-3 filters per field, with 8 exposures per filter, resulting in 3000-4000 data points per star over a time span of 3.5 years. To find the variables, we select objects with > 200 detections, and remove those flagged as saturated. No other cuts are used. There are approximately 2.4 million objects that fit this criteria, with magnitudes between 13th and 24th. These objects are then passed through a lomb-scargle fitting routine to determine periodicity. After a periodicity cut, the candidates are classified by eye into different types of variable stars. We have identified several thousand periodic variable stars, with periods ranging between a few minutes to a few days. We compare our findings to the variable star catalogs within Vizier and AAVSO. In particular, for field MD02, we recover all the variables that are faint in Vizier, and we find good agreement with the periods reported in Vizier.

  17. Edward S. Curtis's The North American Indian

    Science.gov Websites

    Northwestern University Digital Library Collections Edward S. Curtis's The North American Indian , supported largely by funds from the Institute for Museum and Library Services. Edward S. Curtis ca.1899 special.collections@northwestern.edu Northwestern University seal NUcat | Electronic Resources | Library Home | Search

  18. Immediate Outcomes of Aortic Valve Replacement with Sutureless versus Stentless Bioprosthesis.

    PubMed

    Ihsan Parlar, Ali; Onur Hanedan, Muhammet; Mataraci, Ilker; Ali Yuruk, Mehmet; Sayar, Ufuk; Kemal Arslan, Ali; Ozer, Tanil

    2016-01-01

    Aortic valve replacement (AVR) with a sutureless valve is an innovative therapy in high-risk elderly patients. The study aim was to compare the early results of AVR using sutureless aortic valves or stentless aortic bioprostheses. A retrospective analysis was conducted of 55 patients who underwent AVR with either a sutureless valve (Perceval S; n = 24 or Edwards Intuity; n = 9) or a stentless valve (Sorin Freedom SOLO™; n = 22). Baseline patient characteristics were similar in both groups, except for NYHA class. Concomitant procedures were performed in 17 patients (51.5%) of the sutureless group and in nine patients (40.9%) of the stentless group (p = 0.44). The aortic cross-clamp time was 55 ± 23 min in the sutureless group and 102 ± 36 min in the stentless group (p <0.0001), while the postoperative peak aortic gradient was 19.5 ± 5.0 mmHg and 29.3 ± 15.4 mmHg for the sutureless group and stentless group, respectively (p = 0.037). The postoperative mean gradient was 9.3 ± 3.4 mmHg for the sutureless group and 15.1 ± 10.5 mmHg for the stentless group (p = 0.06). Blood product transfusion was required less frequently by the sutureless group, but drainage and bleeding was similar in both groups. The intensive care unit and hospital stays were significantly shorter in favor of the sutureless group. One sutureless patient (3.0%) and two stentless patients (9.1%) died in hospital (p = 0.557). Early results of the present study suggested that surgical AVR with a sutureless valve is associated with a good hemodynamic performance and an improved early outcome.

  19. KEGS Transients Discovered by a Pan-STARRS1 Search of the Kepler Campaign 16 Field

    NASA Astrophysics Data System (ADS)

    Smith, K. W.; Rest, A.; Tucker, B. E.; Garnavich, P. M.; Margheim, S.; Kasen, D.; Olling, R.; Shaya, E.; Narayan, G.; Villar, A.; Forster, F.; Mushotzky, R.; Zenteno, A.; James, D.; Smith, R. Chris; Dotson, J. L.; Barentsen, G.; Gully-Santiago, M.; Smartt, S. J.; Wright, D. E.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Schultz, A.; Magnier, E.; Waters, C.; Bulger, J.; Wainscoat, R. J.

    2018-01-01

    We report the following transients discovered by Pan-STARRS1 during a targeted search of the Kepler Campaign 16 field as part of the K2 Extragalactic Survey (KEGS) for Transients (see http://www.mso.anu.edu.au/kegs/).

  20. Griffith Edwards' rigorous sympathy with Alcoholics Anonymous.

    PubMed

    Humphreys, Keith

    2015-07-01

    Griffith Edwards made empirical contributions early in his career to the literature on Alcoholics Anonymous (AA), but the attitude he adopted towards AA and other peer-led mutual help initiatives constitutes an even more important legacy. Unlike many treatment professionals who dismissed the value of AA or were threatened by its non-professional approach, Edwards was consistently respectful of the organization. However, he never became an uncritical booster of AA or overgeneralized what could be learnt from it. Future scholarly and clinical endeavors concerning addiction-related mutual help initiatives will benefit by continuing Edwards' tradition of 'rigorous sympathy'. © 2015 Society for the Study of Addiction.

  1. Measuring Dark Energy Properties with Photometrically Classified Pan-STARRS Supernovae. II. Cosmological Parameters

    NASA Astrophysics Data System (ADS)

    Jones, D. O.; Scolnic, D. M.; Riess, A. G.; Rest, A.; Kirshner, R. P.; Berger, E.; Kessler, R.; Pan, Y.-C.; Foley, R. J.; Chornock, R.; Ortega, C. A.; Challis, P. J.; Burgett, W. S.; Chambers, K. C.; Draper, P. W.; Flewelling, H.; Huber, M. E.; Kaiser, N.; Kudritzki, R.-P.; Metcalfe, N.; Tonry, J.; Wainscoat, R. J.; Waters, C.; Gall, E. E. E.; Kotak, R.; McCrum, M.; Smartt, S. J.; Smith, K. W.

    2018-04-01

    We use 1169 Pan-STARRS supernovae (SNe) and 195 low-z (z < 0.1) SNe Ia to measure cosmological parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can be used to infer unbiased cosmological parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with cosmic microwave background (CMB) constraints from Planck, we measure the dark energy equation-of-state parameter w to be ‑0.989 ± 0.057 (stat+sys). If w evolves with redshift as w(a) = w 0 + w a (1 ‑ a), we find w 0 = ‑0.912 ± 0.149 and w a = ‑0.513 ± 0.826. These results are consistent with cosmological parameters from the Joint Light-curve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a w differing by more than 2% from the baseline measurement. The systematic uncertainty on w due to marginalizing over CC SN contamination, {σ }wCC}=0.012, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6σ) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-z analyses. Our data provide one of the best current constraints on w, demonstrating that samples with ∼5% CC SN contamination can give competitive cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.

  2. Measuring M Dwarf Rotation in the Pan-STARRS 1 Medium Deep Survey

    NASA Astrophysics Data System (ADS)

    Fong, Erin R.; Williams, Peter K. G.; Berger, Edo

    2016-01-01

    The rise of large-format CCDs and automated detection methods has greatly increased the tractability of large-scale studies of stellar rotation. Studies of the relationship between stellar rotation and magnetic activity show a strong correlation, supporting the concept of a rotationally-driven dynamo. However, the number of confirmed rotation periods for stars in the fully convective regime, whose magnetic dynamos are less well understood, remains low. Here we report on ongoing work to measure rotation periods for the M dwarf stellar population observed by the Pan-STARRS 1 Medium Deep Survey (PS1/MDS). We refine an initial sample of around 4.3 million sources using color cuts in each of the five Pan-STARRS 1 filters. Of these sources, we estimate there to be around 135,000 sources which are candidate M dwarfs with a spectral type of M1 or higher. We discuss the outcomes of various rotation period detection methods and present preliminary results. This work is supported in part by the National Science Foundation REU and Department of Defense ASSURE programs under NSF Grant no. 1262851 and by the Smithsonian Institution.

  3. A map of dust reddening to 4.5 kpc from Pan-STARRS1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schlafly, E. F.; Rix, H.-W.; Martin, N. F.

    2014-07-01

    We present a map of the dust reddening to 4.5 kpc derived from Pan-STARRS1 stellar photometry. The map covers almost the entire sky north of declination –30° at a resolution of 7'-14', and is based on the estimated distances and reddenings to more than 500 million stars. The technique is designed to map dust in the Galactic plane, where many other techniques are stymied by the presence of multiple dust clouds at different distances along each line of sight. This reddening-based dust map agrees closely with the Schlegel et al. (SFD) far-infrared emission-based dust map away from the Galactic plane,more » and the most prominent differences between the two maps stem from known limitations of SFD in the plane. We also compare the map with Planck, finding likewise good agreement in general at high latitudes. The use of optical data from Pan-STARRS1 yields reddening uncertainty as low as 25 mmag E(B – V).« less

  4. Fatigue life of high-speed ball bearings with silicon nitride balls

    NASA Technical Reports Server (NTRS)

    Parker, R. J.; Zaretsky, E. V.

    1974-01-01

    Hot-pressed silicon nitride was evaluated as a rolling-element bearing material. The five-ball fatigue tester was used to test 12.7-mm- diameter silicon nitride balls at maximum Hertz stresses ranging from 4.27 x 10 to the 9th power n/sq m to 6.21 x 10 to the 9th power n/sq m at a race temperature of 328K. The fatigue life of NC-132 hot-pressed silicon nitride was found to be equal to typical bearing steels and much greater than other ceramic or cermet materials at the same stress levels. A digital computer program was used to predict the fatigue life of 120-mm- bore angular-contact ball bearings containing either steel or silicon nitride balls. The analysis indicates that there is no improvement in the lives of bearings of the same geometry operating at DN values from 2 to 4 million where silicon nitride balls are used in place of steel balls.

  5. In-Graft Endovascular Stenting Repair for Supravalvular Stenosis From Aortic Rupture After Balloon-Expanding Transcatheter Aortic Valve Implantation.

    PubMed

    Furukawa, Nobuyuki; Scholtz, Werner; Haas, Nikolaus; Ensminger, Stephan; Gummert, Jan; Börgermann, Jochen

    2015-01-01

    An 81-year-old man with high-grade aortic valve stenosis and status post-coronary artery bypass grafting and supracoronary replacement of the ascending aorta was referred for transcatheter aortic valve implantation. He was in New York Heart Association class III and had dyspnea. After appropriate screening, we implanted a 29-mm SAPIEN XT valve (Edwards Lifesciences, Irvine, CA USA) through a transapical approach because of severe peripheral arterial occlusive disease. Postinterventional aortography revealed correct positioning and function of the valve and free coronary ostia but contrast extravasation in the vicinity of the interposed vascular prosthesis, resulting in severe luminal narrowing. We chose to manage the stenosis with an endovascular stent. After stenting, extravascular compression was markedly reduced, and the pressure gradient disappeared. The patient was discharged home on the 20th postoperative day. Three months later, computed tomography depicted correct positioning of both grafts. The patient's general health is good, and he is now in New York Heart Association class II. This case illustrates a complication of transcatheter aortic valve implantation specific for patients with an ascending aortic graft. Although stenting may be a good solution, as depicted by this case, self-expanding transcatheter aortic valves should be preferred in patients with ascending aortic grafts to avoid the described complication.

  6. 1-Year Outcomes After Transcatheter Aortic Valve Replacement With Balloon-Expandable Versus Self-Expandable Valves: Results From the CHOICE Randomized Clinical Trial.

    PubMed

    Abdel-Wahab, Mohamed; Neumann, Franz-Josef; Mehilli, Julinda; Frerker, Christian; Richardt, Doreen; Landt, Martin; Jose, John; Toelg, Ralph; Kuck, Karl-Heinz; Massberg, Steffen; Robinson, Derek R; El-Mawardy, Mohamed; Richardt, Gert

    2015-08-18

    The use of a balloon-expandable transcatheter heart valve previously resulted in a greater rate of device success compared with a self-expandable transcatheter heart valve. The aim of this study was to evaluate clinical and echocardiographic outcome data at longer term follow-up. The investigator-initiated trial randomized 241 high-risk patients with symptomatic severe aortic stenosis and anatomy suitable for treatment with both balloon- and self-expandable transcatheter heart valves to transfemoral transcatheter aortic valve replacement with either device. Patients were followed-up for 1 year, with assessment of clinical outcomes and echocardiographic evaluation of valve function. At 1 year, the rates of death of any cause (17.4% vs. 12.8%; relative risk [RR]: 1.35; 95% confidence interval [CI]: 0.73 to 2.50; p = 0.37) and of cardiovascular causes (12.4% vs. 9.4%; RR: 1.32; 95% CI: 0.63 to 2.75; p = 0.54) were not statistically significantly different in the balloon- and self-expandable groups, respectively. The frequencies of all strokes (9.1% vs. 3.4%; RR: 2.66; 95% CI: 0.87 to 8.12; p = 0.11) and repeat hospitalization for heart failure (7.4% vs. 12.8%; RR: 0.58; 95% CI: 0.26 to 1.27; p = 0.19) did not statistically significantly differ between the 2 groups. Elevated transvalvular gradients during follow-up were observed in 4 patients in the balloon-expandable group (3.4% vs. 0%; p = 0.12); all were resolved with anticoagulant therapy, suggesting a thrombotic etiology. More than mild paravalvular regurgitation was more frequent in the self-expandable group (1.1% vs. 12.1%; p = 0.005). Despite the higher device success rate with the balloon-expandable valve, 1-year follow-up of patients in CHOICE (Randomized Comparison of Transcatheter Heart Valves in High Risk Patients With Severe Aortic Stenosis: Medtronic CoreValve Versus Edwards SAPIEN XT Trial), with limited statistical power, revealed clinical outcomes after transfemoral transcatheter aortic valve

  7. First data from the Pan-STARRS survey and how to use it

    NASA Astrophysics Data System (ADS)

    Soderblom, David; Pan-STARRS team

    2018-01-01

    Program for this Special Session:Ken ChambersIntroduction to the Pan-STARRS surveyHeather FlewellingThe PS-1 pipeline and data productsEugene MagnierA 3-D view of dust in the GalaxyEddie SchaflyThe PS-1 "ubercal"Dan ScolnicSupernovae in PS-1Suvi GezariTidal disruption events in PS-1Maria DroutTransient events in PS-1Karen MeechMoving targets in PS-1

  8. Golf Ball

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Ultra 500 Series golf balls, introduced in 1995 by Wilson Sporting Goods Company, has 500 dimples arranged in a pattern of 60 spherical triangles. The design employs NASA's aerodynamics technology analysis of air loads of the tank and Shuttle orbiter that was performed under the Space Shuttle External Tank program. According to Wilson, this technology provides 'the most symmetrical ball surface available, sustaining initial velocity longer and producing the most stable ball flight for unmatched accuracy and distance.' The dimples are in three sizes, shapes and depths mathematically positioned for the best effect. The selection of dimples and their placement optimizes the interaction of opposing forces of lift and drag. Large dimples reduce air drag, enhance lift, and maintain spin for distance. Small dimples prevent excessive lift that destabilizes the ball flight and the medium size dimples blend the other two.

  9. STS-4 landing at Edwards Air Foce Base, California

    NASA Technical Reports Server (NTRS)

    1982-01-01

    STS-4 landing at Edwards Air Foce Base, California. Actor Roy Rogers with Astronauts Jerry L. Ross, left, and Guy S. Gardner at Edwards for the STS-4 landing on July 1, 1982. Also present (behind Gardner at extreme right) was former Astronaut Edwin E. Aldrin, Jr. (33226); President Ronald Reagan and First Lady Nancy Reagan meet Astronauts Thomas K. Mattingly, II., right, and Henry W. Hartsfield, Jr., after the landing of the Columbia at Edwards (33227,33230); Space Shuttle Columbia, followed by two T-38 chase planes, touches down on Edwards Air Force Base's Runway 22 to complete mission. In this view, one chase plane appears to be directly above and behind the Columbia, whose nose wheels have not yet touched ground. The other plane appears to be further up front (33228); The rear wheels of the Columbia touch down on the Edwards AFB runway. There are no chase planes in sight in this photo (33229).

  10. Transformation of Pan-STARRS1 gri to Stetson BVRI magnitudes. Photometry of small bodies observations.

    NASA Astrophysics Data System (ADS)

    Kostov, A.; Bonev, T.

    2018-02-01

    The UBVRI broad band photometric system is widely used in CCD astronomy. There are a lot of sets of standard stars for this photometric system, the Landolt's and Stetson's catalogues being the most precise and reliable. Another photometric system, recently considerably spread in CCD observations is ugriz, which originates from the Sloan Digital Sky Survey (SDSS) and has now many variations based on its 5 broad-band filters. One of the photometric systems based on it is The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). In this paper we compare the BVRI magnitudes in the Stetson catalogue of standard stars with the magnitudes of the corresponding stars in the Pan-STARRS1 (PS1) grizyw catalogue. Transformations between these two systems are presented and discussed. An algorithm for data reduction and calibration is developed and its functionality is demonstrated in the magnitude determination of an asteroid.

  11. Effect of ball geometry on endurance limit in bending of drilled balls

    NASA Technical Reports Server (NTRS)

    Munson, H. E.

    1975-01-01

    Four designs of drilled (cylindrically hollow) balls were tested for resistance to bending fatigue. Bending fatigue has been demonstrated to be a limiting factor in previous evaluations of the drilled ball concept. A web reinforced drilled ball was most successful in resisting bending fatigue. Another design of through drilled design, involving a heavier wall than the standard reference ball, also showed significant improvement in resistance to bending fatigue.

  12. Fizz-Ball Fizzics

    ERIC Educational Resources Information Center

    Moinester, Murray; Gerland, Lars; Liger-Belair, Gerard; Ocherashvili, Aharon

    2012-01-01

    We describe the fluid dynamics principles governing the up-down oscillatory cycling of a bubble-covered, low-density, low-mass ball of material (referred to henceforth as a "fizz-ball") immersed inside a glass of bubbling (super-saturated) carbonated liquid. The bubbles serve to desaturate the liquid of excess CO[subscript 2]. The fizz-ball acts…

  13. Ball Bearing Mechanics

    NASA Technical Reports Server (NTRS)

    Hamrock, Bernard J.; Dowson, Duncan

    1981-01-01

    Load-deflection relationships for different types of elliptical contacts such as those found in a ball bearing are developed. Simplified expressions that allow quick calculations of deformation to be made simply from a knowledge of the applied load, the material properties, and the geometry of the contacting elements are presented. Ball bearings subjected to radial, thrust and combined ball loads are analyzed. A design criterion for fatigue life of ball bearings is developed. The section of a satisfactory lubricant, as well as describing systems that provide a constant flow of lubricant to the contact, is considered.

  14. Edward Everett Hale

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The first known proposal for a marned-satellite appeared in a story by Edward Everett Hale entitled The Brick Moon. The story involved a group of young Bostonians who planned to put an artificial satellite into polar orbit for sailors to use to determine longitude accurately and easily.

  15. Measurement and reconstruction of the leaflet geometry for a pericardial artificial heart valve.

    PubMed

    Jiang, Hongjun; Campbell, Gord; Xi, Fengfeng

    2005-03-01

    This paper describes the measurement and reconstruction of the leaflet geometry for a pericardial heart valve. Tasks involved include mapping the leaflet geometries by laser digitizing and reconstructing the 3D freeform leaflet surface based on a laser scanned profile. The challenge is to design a prosthetic valve that maximizes the benefits offered to the recipient as compared to the normally operating naturally-occurring valve. This research was prompted by the fact that artificial heart valve bioprostheses do not provide long life durability comparable to the natural heart valve, together with the anticipated benefits associated with defining the valve geometries, especially the leaflet geometries for the bioprosthetic and human valves, in order to create a replicate valve fabricated from synthetic materials. Our method applies the concept of reverse engineering in order to reconstruct the freeform surface geometry. A Brown & Shape coordinate measuring machine (CMM) equipped with a HyMARC laser-digitizing system was used to measure the leaflet profiles of a Baxter Carpentier-Edwards pericardial heart valve. The computer software, Polyworks was used to pre-process the raw data obtained from the scanning, which included merging images, eliminating duplicate points, and adding interpolated points. Three methods, creating a mesh model from cloud points, creating a freeform surface from cloud points, and generating a freeform surface by B-splines are presented in this paper to reconstruct the freeform leaflet surface. The mesh model created using Polyworks can be used for rapid prototyping and visualization. To fit a freeform surface to cloud points is straightforward but the rendering of a smooth surface is usually unpredictable. A surface fitted by a group of B-splines fitted to cloud points was found to be much smoother. This method offers the possibility of manually adjusting the surface curvature, locally. However, the process is complex and requires additional

  16. A Comparative Study of Two Types of Ball-on-Ball Collision

    ERIC Educational Resources Information Center

    White, Colin

    2017-01-01

    This paper describes three methods of measuring the coefficient of restitution (CoR) for two different types of ball-on-ball collision. The first collision type (for which two different CoR measurement procedures are described) is a static, hanging steel ball forming part of a Newton's cradle arrangement, which is then hit by its adjacent…

  17. Long-Term Survival and Freedom From Reoperation After Placement of a Pulmonary Xenograft Valved Conduit.

    PubMed

    Alfieris, George M; Swartz, Michael F; Lehoux, Juan; Bove, Edward L

    2016-08-01

    The optimal choice for pulmonary valve replacement (PVR) remains controversial. This study hypothesized that xenografts used for PVR would result in prolonged long-term survival and freedom from reoperation. Children and adults with congenital heart disease requiring PVR using a xenograft from 1980 to 1985 were reviewed. In all cases, the xenograft valve was either sewn or manufactured into a Dacron conduit, and the conduit was sewn to the pulmonary artery bifurcation. Clinical data were analyzed, and survival and freedom from reoperation were determined using Kaplan-Meier analysis. Twenty-four patients received a xenograft for PVR at 14.6 ± 5.6 years. Conduit size ranged from 21 to 27 mm. Most patients received a Carpentier-Edwards valved conduit (n = 17), followed by a Hancock valved conduit (n = 5) and an Ionescu-Shiley valve sewn into a Dacron graft (n = 2). No perioperative deaths occurred. Reoperation was required mainly for pulmonary stenosis (72.7%), followed by pulmonary insufficiency (18.2%), or both stenosis and insufficiency (9%). Freedom from reoperation was 90%, 56%, 43%, and 14% at 10, 20, 25, and 30 years, respectively. At most recent follow-up the was only death, which was related to severe biventricular failure 25 years after conduit implant. PVR using a xenograft valved conduit results in prolonged freedom from reoperation and excellent long-term survival. These data, which provide long-term follow-up information on xenograft valves after PVR. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Transcatheter aortic valve replacement: historical perspectives, current evidence, and future directions.

    PubMed

    Horne, Aaron; Reineck, Elizabeth A; Hasan, Rani K; Resar, Jon R; Chacko, Matthews

    2014-10-01

    Severe aortic stenosis (AS) results in considerable morbidity and mortality without aortic valve replacement and is expected to increase in prevalence with the aging population. Because AS primarily affects the elderly, many patients with comorbidities are poor candidates for surgical aortic valve replacement (SAVR) and may not be referred. Transcatheter aortic valve replacement (TAVR) has emerged as transformative technology for the management of AS over the past decade. Randomized trials have established the safety and efficacy of TAVR with improved mortality and quality of life compared with medical therapy in inoperable patients, while demonstrating noninferiority and even superiority to SAVR among high-risk operative candidates. However, early studies demonstrated an early penalty of stroke and vascular complications with TAVR as well as increased paravalvular leak as compared with SAVR. Two device platforms have been evaluated and approved for use in the United States: the Edwards SAPIEN and the Medtronic CoreValve. Early studies also suggest cost-effectiveness for TAVR. Ongoing studies are evaluating new iterations of the aforementioned TAVR devices, novel device designs, and applications of TAVR in expanded populations of patients including those with lower risk profiles as well as those with comorbidities that were excluded from early clinical trials. Future improvements in TAVR technology will likely reduce periprocedural and long-term complications. Further studies are needed to confirm device durability over long-term follow-up and explore the applicability of TAVR to broader AS patient populations. Copyright © 2014 Mosby, Inc. All rights reserved.

  19. Individual ball possession in soccer

    PubMed Central

    Hoernig, Martin

    2017-01-01

    This paper describes models for detecting individual and team ball possession in soccer based on position data. The types of ball possession are classified as Individual Ball Possession (IBC), Individual Ball Action (IBA), Individual Ball Control (IBC), Team Ball Possession (TBP), Team Ball Control (TBC) und Team Playmaking (TPM) according to different starting points and endpoints and the type of ball control involved. The machine learning approach used is able to determine how long the ball spends in the sphere of influence of a player based on the distance between the players and the ball together with their direction of motion, speed and the acceleration of the ball. The degree of ball control exhibited during this phase is classified based on the spatio-temporal configuration of the player controlling the ball, the ball itself and opposing players using a Bayesian network. The evaluation and application of this approach uses data from 60 matches in the German Bundesliga season of 2013/14, including 69,667 IBA intervals. The identification rate was F = .88 for IBA and F = .83 for IBP, and the classification rate for IBC was κ = .67. Match analysis showed the following mean values per match: TBP 56:04 ± 5:12 min, TPM 50:01 ± 7:05 min and TBC 17:49 ± 8:13 min. There were 836 ± 424 IBC intervals per match and their number was significantly reduced by -5.1% from the 1st to 2nd half. The analysis of ball possession at the player level indicates shortest accumulated IBC times for the central forwards (0:49 ± 0:43 min) and the longest for goalkeepers (1:38 ± 0:58 min), central defenders (1:38 ± 1:09 min) and central midfielders (1:27 ± 1:08 min). The results could improve performance analysis in soccer, help to detect match events automatically, and allow discernment of higher value tactical structures, which is based on individual ball possession. PMID:28692649

  20. Ban Deodorant Ball Mortar.

    ERIC Educational Resources Information Center

    Carpenter, D. Rae, Jr.; And Others

    1988-01-01

    Discusses a demonstration of vertical collision of two balls. Shows the theoretical height ratio using mathematical expression and diagrams. Compares it with researchers' experimental results. Expands the two-ball collision to multi-ball system. (YP)

  1. Culturally Competent Diabetes Self-Management Education for Mexican Americans: The Starr County Border Health Initiative.

    ERIC Educational Resources Information Center

    Brown, Sharon A.; Garcia, Alexandra A.; Kouzekanani, Kamiar; Hanis, Craig L.

    2002-01-01

    In a culturally competent diabetes self-management intervention in Starr County, Texas, bilingual Mexican American nurses, dieticians, and community workers provided weekly instruction on nutrition, self-monitoring, exercise and other self-care topics. A biweekly support group promoted behavior change. Interviews and examinations with 256 Mexican…

  2. Stent and leaflet stresses in a 26-mm first-generation balloon-expandable transcatheter aortic valve.

    PubMed

    Xuan, Yue; Krishnan, Kapil; Ye, Jian; Dvir, Danny; Guccione, Julius M; Ge, Liang; Tseng, Elaine E

    2017-05-01

    Transcatheter aortic valve replacement is established therapy for high-risk and inoperable patients with severe aortic stenosis, but questions remain regarding long-term durability. Valve design influences durability. Increased leaflet stresses in surgical bioprostheses have been correlated with degeneration; however, transcatheter valve leaflet stresses are unknown. From 2007 to 2014, a majority of US patients received first-generation balloon-expandable transcatheter valves. Our goal was to determine stent and leaflet stresses in this valve design using finite element analyses. A 26-mm Sapien Transcatheter Heart Valve (Edwards Lifesciences, Inc, Irvine, Calif) underwent high-resolution microcomputed tomography scanning to develop precise 3-dimensional geometry of the leaflets, the stent, and the polyethylene terephthalate elements. The stent was modeled using 3-dimensional elements and the leaflets were modeled using shell elements. Stent material properties were based on stainless steel, whereas those for leaflets were obtained from surgical bioprostheses. Noncylindrical Sapien valve geometry was also simulated. Pressure loading to 80 mm Hg and 120 mm Hg was performed using ABAQUS finite element software (Dassault Systèmes, Waltham, Mass). At 80 mm Hg, maximum principal stresses on Sapien leaflets were 1.31 megaspascals (MPa). Peak leaflet stress was observed at commissural tips where leaflets connected to the stent. Maximum principal stresses for the stent were 188.91 MPa and located at stent tips where leaflet commissures were attached. Noncylindrical geometry increased peak principal leaflet stresses by 16%. Using exact geometry from high-resolution scans, the 26-mm Sapien Transcatheter Heart Valve showed that peak stresses for both stent and leaflets were present at commissural tips where leaflets were attached. These regions would be prone to leaflet degeneration. Understanding stresses in first-generation transcatheter valves allows comparison to

  3. Edwards statistical mechanics for jammed granular matter

    NASA Astrophysics Data System (ADS)

    Baule, Adrian; Morone, Flaviano; Herrmann, Hans J.; Makse, Hernán A.

    2018-01-01

    In 1989, Sir Sam Edwards made the visionary proposition to treat jammed granular materials using a volume ensemble of equiprobable jammed states in analogy to thermal equilibrium statistical mechanics, despite their inherent athermal features. Since then, the statistical mechanics approach for jammed matter—one of the very few generalizations of Gibbs-Boltzmann statistical mechanics to out-of-equilibrium matter—has garnered an extraordinary amount of attention by both theorists and experimentalists. Its importance stems from the fact that jammed states of matter are ubiquitous in nature appearing in a broad range of granular and soft materials such as colloids, emulsions, glasses, and biomatter. Indeed, despite being one of the simplest states of matter—primarily governed by the steric interactions between the constitutive particles—a theoretical understanding based on first principles has proved exceedingly challenging. Here a systematic approach to jammed matter based on the Edwards statistical mechanical ensemble is reviewed. The construction of microcanonical and canonical ensembles based on the volume function, which replaces the Hamiltonian in jammed systems, is discussed. The importance of approximation schemes at various levels is emphasized leading to quantitative predictions for ensemble averaged quantities such as packing fractions and contact force distributions. An overview of the phenomenology of jammed states and experiments, simulations, and theoretical models scrutinizing the strong assumptions underlying Edwards approach is given including recent results suggesting the validity of Edwards ergodic hypothesis for jammed states. A theoretical framework for packings whose constitutive particles range from spherical to nonspherical shapes such as dimers, polymers, ellipsoids, spherocylinders or tetrahedra, hard and soft, frictional, frictionless and adhesive, monodisperse, and polydisperse particles in any dimensions is discussed providing

  4. Ceramic Rail-Race Ball Bearings

    NASA Technical Reports Server (NTRS)

    Balzer, Mark A.; Mungas, Greg S.; Peters, Gregory H.

    2010-01-01

    Non-lubricated ball bearings featuring rail races have been proposed for use in mechanisms that are required to function in the presence of mineral dust particles in very low-pressure, dry environments with extended life. Like a conventional ball bearing, the proposed bearing would include an inner and an outer ring separated by balls in rolling contact with the races. However, unlike a conventional ball bearing, the balls would not roll in semi-circular or gothic arch race grooves in the rings: instead, the races would be shaped to form two or more rails (see figure). During operation, the motion of the balls would push dust particles into the spaces between the rails where the particles could not generate rolling resistance for the balls

  5. Hazardous Waste Cleanup: General Electric - Fort Edward in Fort Edward, New York

    EPA Pesticide Factsheets

    This 32-acre General Electric (GE) facility is located approximately 800 feet east of the Hudson River between the Villages of Fort Edward to the south and Hudson Falls to the north. A 200-foot-wide parcel west of the main portion of the site, between Alle

  6. Detonator-activated ball shutter

    DOEpatents

    McWilliams, Roy A.; von Holle, William G.

    1983-01-01

    A detonator-activated ball shutter for closing an aperture in about 300.mu. seconds. The ball shutter containing an aperture through which light, etc., passes, is closed by firing a detonator which propels a projectile for rotating the ball shutter, thereby blocking passage through the aperture.

  7. Transcatheter valve-in-valve therapy using 6 different devices in 4 anatomic positions: Clinical outcomes and technical considerations.

    PubMed

    Conradi, Lenard; Silaschi, Miriam; Seiffert, Moritz; Lubos, Edith; Blankenberg, Stefan; Reichenspurner, Hermann; Schaefer, Ulrich; Treede, Hendrik

    2015-12-01

    Transcatheter valve-in-valve implantation (ViV) is emerging as a novel treatment option for patients with deteriorated bioprostheses. We report our cumulative experience using 6 types of transcatheter heart valves (THVs) in all anatomic positions. Seventy-five consecutive patients (74.1 ± 12.9 years, 50.7% male (38/75), logEuroSCORE I 26.2% ± 17.8%, STS-PROM 8.8% ± 7.4%) receiving ViV procedures from 2008 to 2014 were included for analysis. Data were prospectively gathered and retrospectively analyzed. ViV was performed in aortic (72.0%, 54/75), mitral (22.7%, 17/75), tricuspid (2.7%, 2/75), and pulmonary (2.7%, 2/75) positions. THVs used were Edwards SAPIEN (XT)/SAPIEN3 (52.0%, 39/75), Medtronic Core Valve/Core Valve Evolut(R) (34.7%, 26/75), St Jude Portico (4.0%, 3/75), Boston Scientific Lotus (4.0%, 3/75), Jena Valve (2.7%, 2/75), and Medtronic Engager (2.7%, 2/75). Interval from index procedure to ViV was 9.3 ± 4.9 years. Access was transapical in 53.3% (40/75), transfemoral (transarterial or transvenous) in 42.7% (32/75), transaortic in 2.7% (2/75), and transjugular in 1.3% (1/75). ViV was successful in 97.3% (73/75) with 2 patients requiring sequential THV implantation for initial malpositioning. Overall immediate procedural (≤72 hours) and all-cause 30-day mortality were 2.7% (2/75) and 8.0% (6/75). Corresponding values after aortic ViV were 1.9% (1/54) and 5.6% (3/54). No periprocedural strokes or cases of coronary obstruction occurred. Paravalvular leakage was less than or equal to mild in all cases. After aortic ViV, gradients were max/mean 34.1 ± 14.2/20.1 ± 7.1 mm Hg and effective orifice area (EOA) was 1.5 ± 1.4 cm(2). Corresponding values after mitral ViV were gradients max/mean 14.2 ± 8.2/4.7 ± 3.1 mm Hg and EOA 2.4 ± 0.9 cm(2). ViV can be performed in all anatomic positions with acceptable hemodynamic and clinical outcome in high-risk patients. Increasing importance of ViV can be anticipated considering growing use of surgical

  8. Pan-STARRS Data Release 2

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather

    2018-01-01

    On December 19, 2016, Pan-STARRS released the stacked images, mean attributes catalogs, and static sky catalogs for the 3pi survey, in 5 filters (g,r,i,z,y), covering 3/4 of the sky, everything north of -30 in declination. This set of data is called Data Release 1 (DR1), and it is available to all at http://panstarrs.stsci.edu. It contains more than 10 billion objects, 3 billion of those objects have stack photometry. We give an update on the progress of the forthcoming Data Release (DR2) database, which will provide time domain catalogs and single exposures for the 3pi survey. This includes 3pi data taken between 2010 and 2014, covering approximately 60 epochs per patch of sky, and includes measurements detected in the single exposures as well as forced photometry measurements (photometry measured on single exposures using the positions from sources detected in the stacks). We also provide informations on futures releases (DR3 and beyond), which will contain the rest of the 3pi database (specifically, the data products related to difference imaging), as well as the data products for the Medium Deep (MD) survey.

  9. Detonator-activated ball shutter

    DOEpatents

    McWilliams, R.A.; Holle, W.G. von.

    1983-08-16

    A detonator-activated ball shutter for closing an aperture in about 300[mu] seconds. The ball shutter containing an aperture through which light, etc., passes, is closed by firing a detonator which propels a projectile for rotating the ball shutter, thereby blocking passage through the aperture. 3 figs.

  10. Inserts Automatically Lubricate Ball Bearings

    NASA Technical Reports Server (NTRS)

    Hager, J. A.

    1983-01-01

    Inserts on ball-separator ring of ball bearings provide continuous film of lubricant on ball surfaces. Inserts are machined or molded. Small inserts in ball pockets provide steady supply of lubricant. Technique is utilized on equipment for which maintenance is often poor and lubrication interval is uncertain, such as household appliances, automobiles, and marine engines.

  11. The flaws in the detail of an observational study on transcatheter aortic valve implantation versus surgical aortic valve replacement in intermediate-risks patients.

    PubMed

    Barili, Fabio; Freemantle, Nick; Folliguet, Thierry; Muneretto, Claudio; De Bonis, Michele; Czerny, Martin; Obadia, Jean Francois; Al-Attar, Nawwar; Bonaros, Nikolaos; Kluin, Jolanda; Lorusso, Roberto; Punjabi, Prakash; Sadaba, Rafael; Suwalski, Piotr; Benedetto, Umberto; Böning, Andreas; Falk, Volkmar; Sousa-Uva, Miguel; Kappetein, Pieter A; Menicanti, Lorenzo

    2017-06-01

    The PARTNER group recently published a comparison between the latest generation SAPIEN 3 transcatheter aortic valve implantation (TAVI) system (Edwards Lifesciences, Irvine, CA, USA) and surgical aortic valve replacement (SAVR) in intermediate-risk patients, apparently demonstrating superiority of the TAVI and suggesting that TAVI might be the preferred treatment method in this risk class of patients. Nonetheless, assessment of the non-randomized methodology used in this comparison reveals challenges that should be addressed in order to elucidate the validity of the results. The study by Thourani and colleagues showed several major methodological concerns: suboptimal methods in propensity score analysis with evident misspecification of the propensity scores (PS; no adjustment for the most significantly different covariates: left ventricular ejection fraction, moderate-severe mitral regurgitation and associated procedures); use of PS quintiles rather than matching; inference on not-adjusted Kaplan-Meier curves, although the authors correctly claimed for the need of balancing score adjusting for confounding factors in order to have unbiased estimates of the treatment effect; evidence of poor fit; lack of data on valve-related death.These methodological flaws invalidate direct comparison between treatments and cannot support authors' conclusions that TAVI with SAPIEN 3 in intermediate-risk patients is superior to surgery and might be the preferred treatment alternative to surgery. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  12. Measuring Cosmological Parameters with Photometrically Classified Pan-STARRS Supernovae

    NASA Astrophysics Data System (ADS)

    Jones, David; Scolnic, Daniel; Riess, Adam; Rest, Armin; Kirshner, Robert; Berger, Edo; Kessler, Rick; Pan, Yen-Chen; Foley, Ryan; Chornock, Ryan; Ortega, Carolyn; Challis, Peter; Burgett, William; Chambers, Kenneth; Draper, Peter; Flewelling, Heather; Huber, Mark; Kaiser, Nick; Kudritzki, Rolf; Metcalfe, Nigel; Tonry, John; Wainscoat, Richard J.; Waters, Chris; Gall, E. E. E.; Kotak, Rubina; McCrum, Matt; Smartt, Stephen; Smith, Ken

    2018-01-01

    We use nearly 1,200 supernovae (SNe) from Pan-STARRS and ~200 low-z (z < 0.1) SNe Ia to measure cosmological parameters. Though most of these SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can still be used to infer unbiased cosmological parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous compilation of SNe Ia. Combining SNe with Cosmic Microwave Background (CMB) constraints from the Planck satellite, we measure the dark energy equation of state parameter w to be -0.986±0.058 (stat+sys). If we allow w to evolve with redshift as w(a) = w0 + wa(1-a), we find w0 = -0.923±0.148 and wa = -0.404±0.797. These results are consistent with measurements of cosmological parameters from the JLA and from a new analysis of 1049 spectroscopically confirmed SNe Ia (Scolnic et al. 2017). We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling the CC SN contamination, finding that none of these variants gives a w that differs by more than 1% from the baseline measurement. The systematic uncertainty on w due to marginalizing over the CC SN contamination, σwCC = 0.019, is approximately equal to the photometric calibration uncertainty and is lower than the systematic uncertainty in the SN\\,Ia dispersion model (σwdisp = 0.024). Our data provide one of the best current constraints on w, demonstrating that samples with ~5% CC SN contamination can give competitive cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.

  13. The CO2 Abundance in Comets C2012 K1 (PanSTARRS), C2012 K5 (LINEAR), and 290P Jager as Measured with Spitzer

    NASA Technical Reports Server (NTRS)

    McKay, Adam J.; Kelley, Michael S.P.; Cochran, Anita L.; Bodewits, Dennis; DiSanti, Michael A.; Dello Russo, Neil; Lisse, Carey M.

    2015-01-01

    Carbon dioxide is one of the most abundant ices present in comets and is therefore important for understanding cometary composition and activity. We present analysis of observations of CO2 and [O I] emission in three comets to measure the CO2 abundance and evaluate the possibility of employing observations of [O I] emission in comets as a proxy for CO2. We obtained NIR imaging sensitive to CO2 of comets C/2012 K1 (PanSTARRS), C/2012 K5 (LINEAR), and 290P/Jager with the IRAC instrument on Spitzer. We acquired observations of [O I] emission in these comets with the ARCES echelle spectrometer mounted on the 3.5-m telescope at Apache Point Observatory and observations of OH with the Swift observatory (PanSTARRS) and with Keck HIRES (Jager). The CO2/H2O ratios derived from the Spitzer images are 12.6 +/- 1.3% (PanSTARRS), 28.9 +/- 3.6% (LINEAR), and 31.3 +/- 4.2% (Jager). These abundances are derived under the assumption that contamination from CO emission is negligible. The CO2 abundance for PanSTARRS is close to the average abundance measured in comets at similar heliocentric distance to date, while the abundances measured for LINEAR and Jager are significantly larger than the average abundance. From the coma morphology observed in PanSTARRS and the assumed gas expansion velocity, we derive a rotation period for the nucleus of about 9.2 h. Comparison of H2O production rates derived from ARCES and Swift data, as well as other observations, suggest the possibility of sublimation from icy grains in the inner coma. We evaluate the possibility that the [O I] emission can be employed as a proxy for CO2 by comparing CO2/H2O ratios inferred from the [O I] lines to those measured directly by Spitzer. We find that for PanSTARRS we can reproduce the observed CO2 abundance to an accuracy of approximately 20%. For LINEAR and Jager, we were only able to obtain upper limits on the CO2 abundance inferred from the [O I] lines. These upper limits are consistent with the CO2 abundances

  14. Transcatheter Aortic Valve-in-Valve Procedure in Patients with Bioprosthetic Structural Valve Deterioration

    PubMed Central

    Reul, Ross M.; Ramchandani, Mahesh K.; Reardon, Michael J.

    2017-01-01

    Surgical aortic valve replacement is the gold standard procedure to treat patients with severe, symptomatic aortic valve stenosis or insufficiency. Bioprosthetic valves are used for surgical aortic valve replacement with a much greater prevalence than mechanical valves. However, bioprosthetic valves may fail over time because of structural valve deterioration; this often requires intervention due to severe bioprosthetic valve stenosis or regurgitation or a combination of both. In select patients, transcatheter aortic valve replacement is an alternative to surgical aortic valve replacement. Transcatheter valve-in-valve (ViV) replacement is performed by implanting a transcatheter heart valve within a failing bioprosthetic valve. The transcatheter ViV operation is a less invasive procedure compared with reoperative surgical aortic valve replacement, but it has been associated with specific complications and requires extensive preoperative work-up and planning by the heart team. Data from experimental studies and analyses of results from clinical procedures have led to strategies to improve outcomes of these procedures. The type, size, and implant position of the transcatheter valve can be optimized for individual patients with knowledge of detailed dimensions of the surgical valve and radiographic and echocardiographic measurements of the patient's anatomy. Understanding the complexities of the ViV procedure can lead surgeons to make choices during the original surgical valve implantation that can make a future ViV operation more technically feasible years before it is required. PMID:29743998

  15. Optical and Acoustic Sensor-Based 3D Ball Motion Estimation for Ball Sport Simulators †.

    PubMed

    Seo, Sang-Woo; Kim, Myunggyu; Kim, Yejin

    2018-04-25

    Estimation of the motion of ball-shaped objects is essential for the operation of ball sport simulators. In this paper, we propose an estimation system for 3D ball motion, including speed and angle of projection, by using acoustic vector and infrared (IR) scanning sensors. Our system is comprised of three steps to estimate a ball motion: sound-based ball firing detection, sound source localization, and IR scanning for motion analysis. First, an impulsive sound classification based on the mel-frequency cepstrum and feed-forward neural network is introduced to detect the ball launch sound. An impulsive sound source localization using a 2D microelectromechanical system (MEMS) microphones and delay-and-sum beamforming is presented to estimate the firing position. The time and position of a ball in 3D space is determined from a high-speed infrared scanning method. Our experimental results demonstrate that the estimation of ball motion based on sound allows a wider activity area than similar camera-based methods. Thus, it can be practically applied to various simulations in sports such as soccer and baseball.

  16. [Stapled transanal rectal resection (STARR) in the treatment of rectocele: personal experience].

    PubMed

    Guarnieri, Alfredo; Cesaretti, Manuela; Tirone, Andrea; Vuolo, Giuseppe; Verre, Luigi; Savelli, Vinno; Piccolomini, Alessandro; Di Cosmo, Leonardo; Carli, Anton Ferdinando; Burroni, Mariagrazia; Pitzalis, Marcella

    2008-01-01

    Rectocele is an organic cause of chronic constipation, with a prevalence ranging from 8.95% to 12% in Europe and United States. Necessarily, the approach for rectocele repair is a surgical operation. Stapled transanal rectal resection (STARR) is safe and effective in the treatment of obstructed defecation syndrome. The authors' experience suggests that the surgical operation needs to be combined to rehabilitation exercises, before and after the surgical treatment, in order to strengthen the muscles of the pelvic pavement. From January 2005 to January 2007, 20 patients with outlet obstruction underwent STARR. Patients were selected for operation based on a strict diagnostic protocol: anamnesis, clinical examination, coloproctological and urogynaecological examinations, defecography, anorectal manometry, transrectal ultrasonography and peritoneal electromyography. The therapeutic protocol consists of 3 parts: phase I: rehabilitation of the pelvic pavement; phase II: surgical operation; III phase: post-surgical rehabilitation of the pelvic pavement; The clinical result was classified into: excellent (6 patients), when all constipation symptoms disappeared, good (11 patients), when patient has 1 or 2 obstructed defecation episodes treated with a laxative, fairly good (2 patients), more than 2 episodes, and poor (1 patient), when surgical operation doesn't improve any of the symptoms. Our results, confirmed by the literature, suggest that Longo's technique should be considered as gold standard for rectocele treatment.

  17. Integrating bio-prosthetic valves in the Fontan operation - Novel treatment to control retrograde flow in caval veins

    NASA Astrophysics Data System (ADS)

    Vukicevic, Marija; Conover, Timothy; Zhou, Jian; Hsia, Tain-Yen; Figliola, Richard

    2012-11-01

    For a child born with only one functional heart ventricle, the sequence of palliative surgeries typically culminates in the Fontan operation. This procedure is usually successful initially, but leads to later complications, for reasons not fully understood. Examples are respiratory-dependent retrograde flows in the caval and hepatic veins, and increased pulmonary vascular resistance (PVR), hypothesized to be responsible for elevated pressure in the liver and disease of the liver and intestines. Here we study the parameters responsible for retrograde flows in the inferior vena cava (IVC) and hepatic vein (HV), and investigate two novel interventions to control retrograde flow: implanting either a Medtronic Contegra valved conduit or an Edwards lifescience pericardial aortic valve in the IVC or HV. We performed the experiments in a multi-scale, patient specific mock circuit, with normal and elevated PVR, towards the optimization of the Fontan circulation. The results show that both valves can significantly reduce retrograde flows in the veins, suggesting potential advantages in the treatment of the patients with congenital heart diseases. Fondation Leducq

  18. Response bias, weighting adjustments, and design effects in the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS)

    PubMed Central

    Kessler, Ronald C.; Heeringa, Steven G.; Colpe, Lisa J.; Fullerton, Carol S.; Gebler, Nancy; Hwang, Irving; Naifeh, James A.; Nock, Matthew K.; Sampson, Nancy A.; Schoenbaum, Michael; Zaslavsky, Alan M.; Stein, Murray B.; Ursano, Robert J.

    2014-01-01

    The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) is a multi-component epidemiological and neurobiological study designed to generate actionable recommendations to reduce U.S. Army suicides and increase knowledge about determinants of suicidality. Three Army STARRS component studies are large-scale surveys: one of new soldiers prior to beginning Basic Combat Training (BCT; n=50,765 completed self-administered questionnaires); another of other soldiers exclusive of those in BCT (n=35,372); and a third of three Brigade Combat Teams about to deploy to Afghanistan who are being followed multiple times after returning from deployment (n= 9,421). Although the response rates in these surveys are quite good (72.0-90.8%), questions can be raised about sample biases in estimating prevalence of mental disorders and suicidality, the main outcomes of the surveys based on evidence that people in the general population with mental disorders are under-represented in community surveys. This paper presents the results of analyses designed to determine whether such bias exists in the Army STARRS surveys and, if so, to develop weights to correct for these biases. Data are also presented on sample inefficiencies introduced by weighting and sample clustering and on analyses of the trade-off between bias and efficiency in weight trimming. PMID:24318218

  19. 02-NIF Dedication: Edward Moses

    ScienceCinema

    Edward Moses

    2017-12-09

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by NIF Director Edward Moses.

  20. Comparison of outcomes of tricuspid annuloplasty with 3D-rigid versus flexible prosthetic ring for functional tricuspid regurgitation secondary to rheumatic mitral valve disease.

    PubMed

    Wang, Haiping; Liu, Xiancheng; Wang, Xin; Lv, Zhenqian; Liu, Xiaojun; Xu, Ping

    2016-11-01

    Annuloplasty bands and rings are widely used for repairing functional tricuspid regurgitation (FTR). However, the question regarding which is the ideal annuloplasty device remains unclear. The aim of this study was to compare the efficacy and mid-term durability of tricuspid ring annuloplasty for FTR secondary to rheumatic mitral valve disease using flexible Cosgrove-Edwards band and the rigid Edwards MC3 ring (Edwards Lifesciences, LLC, Irvine, CA, USA). We retrospectively collected the clinical data of those who underwent mitral valve replacement (MVR) in concomitant with tricuspid ring annuloplasty from 2009 to 2013. The flexible band was used in 46 patients (flexible group), and the 3D rigid ring was used in 60 patients (rigid group). Echocardiographic evaluation of tricuspid function was performed preoperatively and postoperatively. The grade of TR was significantly improved compared to preoperative values in two groups. There was no significant difference regarding postoperative TR grade between the two groups at 1 week and 2-3 months but there was statistical significant difference at postoperative 6-12 months, and 2-3 years. During the follow up period, 25 of 46 patients (54.3%) in flexible group and 22 of 60 patients (30.3%) in rigid group developed recurrent TR. Freedom from recurrent TR in flexible group is significant lower than rigid group in each postoperative follow up period. These findings suggest that 3D rigid ring annuloplasty might be more effective for tricuspid ring annuloplasty in FTR in mid-term postoperative periods when compared to flexible band.

  1. Comparison of outcomes of tricuspid annuloplasty with 3D-rigid versus flexible prosthetic ring for functional tricuspid regurgitation secondary to rheumatic mitral valve disease

    PubMed Central

    Wang, Haiping; Wang, Xin; Lv, Zhenqian; Liu, Xiaojun

    2016-01-01

    Background Annuloplasty bands and rings are widely used for repairing functional tricuspid regurgitation (FTR). However, the question regarding which is the ideal annuloplasty device remains unclear. The aim of this study was to compare the efficacy and mid-term durability of tricuspid ring annuloplasty for FTR secondary to rheumatic mitral valve disease using flexible Cosgrove-Edwards band and the rigid Edwards MC3 ring (Edwards Lifesciences, LLC, Irvine, CA, USA). Methods We retrospectively collected the clinical data of those who underwent mitral valve replacement (MVR) in concomitant with tricuspid ring annuloplasty from 2009 to 2013. The flexible band was used in 46 patients (flexible group), and the 3D rigid ring was used in 60 patients (rigid group). Echocardiographic evaluation of tricuspid function was performed preoperatively and postoperatively. Results The grade of TR was significantly improved compared to preoperative values in two groups. There was no significant difference regarding postoperative TR grade between the two groups at 1 week and 2–3 months but there was statistical significant difference at postoperative 6–12 months, and 2–3 years. During the follow up period, 25 of 46 patients (54.3%) in flexible group and 22 of 60 patients (30.3%) in rigid group developed recurrent TR. Freedom from recurrent TR in flexible group is significant lower than rigid group in each postoperative follow up period. Conclusions These findings suggest that 3D rigid ring annuloplasty might be more effective for tricuspid ring annuloplasty in FTR in mid-term postoperative periods when compared to flexible band. PMID:28066587

  2. CHANDRA OBSERVATIONS OF COMETS C/2012 S1 (ISON) AND C/2011 L4 (PanSTARRS)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Snios, Bradford; Kharchenko, Vasili; Lisse, Carey M.

    2016-02-20

    We present our results on the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer (ACIS) observations of the bright Oort Cloud comets C/2012 S1 (ISON) and C/2011 L4 (PanSTARRS). ISON was observed between 2013 October 31–November 06 during variable speed solar wind (SW), and PanSTARRS was observed between 2013 April 17–23 during fast SW. ISON produced an extended parabolic X-ray morphology consistent with a collisionally thick coma, while PanSTARRS demonstrated only a diffuse X-ray-emitting region. We consider these emissions to be from charge exchange (CX) and model each comet's emission spectrum from first principles accordingly. Our model agrees with the observationalmore » spectra and also generates composition ratios for heavy, highly charged SW ions interacting with the cometary atmosphere. We compare our derived SW ion compositions to observational data and find a strong agreement between them. These results further demonstrate the utility of CX emissions as a remote diagnostics tool of both astrophysical plasma interaction and SW composition. In addition, we observe potential soft X-ray emissions via ACIS around 0.2 keV from both comets that are correlated in intensity to the hard X-ray emissions between 0.4–1.0 keV. We fit our CX model to these emissions, but our lack of a unique solution at low energies makes it impossible to conclude if they are cometary CX in origin. Finally, we discuss probable emission mechanism sources for the soft X-rays and explore new opportunities these findings present in understanding cometary emission processes via Chandra.« less

  3. The President Clinton crisis and the Starr report: children's perceptions and parents' awareness.

    PubMed

    Kelley, B R; Beauchesne, M A; Babington, L M; Christensen, M H; Patsdaughter, C A

    1999-01-01

    The media have suggested that the President Clinton crisis, as publicized by the Starr Report, has had detrimental effects on school-age children. Parents, too, have been concerned that their children are confused about the presidential controversies involving dishonesty, mistrust, betrayal, infidelity, and misuse of authority. The purpose of this study was to explore the perceptions and reactions of school-age children to information surrounding the President Clinton situation, as well as parents' perceptions of their children's knowledge and reactions. A descriptive, qualitative design was used in this study. Data collection took place during the 2-week period following publication of the 1998 Starr Report. Fifty-one parents and 67 school-age children were interviewed using semi-structured interview guides with 5 open-ended questions addressing the President Clinton situation. Major themes that emerged from children's interviews were lying, getting caught, infidelity, and role modeling. Parents' awareness of their children's knowledge regarding the President Clinton situation varied; few were aware of the depth of knowledge their children had, nor had they discussed this situation with their children. Findings have relevance for nurse practitioners as they support parents in listening to and talking with their children about tough issues such as morality and sexuality in the context of real life events.

  4. Flapper Valve and Hayfork: Functional anatomy and taxonomic potential of the Gastric Mill of Bairdioidea (Ostracoda, Podocopida).

    PubMed

    Maddocks, Rosalie F

    2018-02-07

    The chewing apparatus of the Bairdioidea has been described just once and is rarely illustrated, but it might have more taxonomic significance than commonly supposed. It is constructed as a flapper valve (hinged check valve), which is unique among Ostracoda and unusual among animals. It projects into the midgut and is substantially enveloped by it. It serves three functions: to move bites of food into the stomach, to close the esophagus against back-flow, and to pack strands of food and mucus onto the rotating food ball. It is probably less effective for macerating the food to reduce particle size. Two braces anchor this structure to the lateral wall of the forehead. It is lined by cuticle that is shed at each molt, and the formation of food balls is interrupted during molting. In its construction and action, this apparatus is quite unlike the gastric mill of decapod crustaceans, and it shows only distant homology to the dorsal Wulst of Cypridoidea. Some architectural details differ among families and genera. The well-sclerotized plate has some potential for fossil preservation in exceptional circumstances. A revised anatomical analysis is presented, together with an annotated glossary of terms.

  5. Development and Characterization Testing of an Air Pulsation Valve for a Pulse Detonation Engine Supersonic Parametric Inlet Test Section

    NASA Technical Reports Server (NTRS)

    Tornabene, Robert

    2005-01-01

    In pulse detonation engines, the potential exists for gas pulses from the combustor to travel upstream and adversely affect the inlet performance of the engine. In order to determine the effect of these high frequency pulses on the inlet performance, an air pulsation valve was developed to provide air pulses downstream of a supersonic parametric inlet test section. The purpose of this report is to document the design and characterization tests that were performed on a pulsation valve that was tested at the NASA Glenn Research Center 1x1 Supersonic Wind Tunnel (SWT) test facility. The high air flow pulsation valve design philosophy and analyses performed are discussed and characterization test results are presented. The pulsation valve model was devised based on the concept of using a free spinning ball valve driven from a variable speed electric motor to generate air flow pulses at preset frequencies. In order to deliver the proper flow rate, the flow port was contoured to maximize flow rate and minimize pressure drop. To obtain sharp pressure spikes the valve flow port was designed to be as narrow as possible to minimize port dwell time.

  6. 76 FR 76710 - Baine, Edward H.; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-08

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ID-6541-001] Baine, Edward H.; Notice of Filing Take notice that on December 1, 2011, Edward H. Baine submitted for filing, an application for authority to hold interlocking positions, pursuant to section 305(b) of the Federal Power Act...

  7. Enhancing the Bounce of a Ball

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2010-10-01

    In sports such as baseball, softball, golf, and tennis, a common objective is to hit the ball as fast or as far as possible. Another common objective is to hit the ball so that it spins as fast as possible, since the trajectory of the ball through the air is strongly affected by ball spin. In an attempt to enhance both the coefficient of restitution (COR) and the spin of a golf ball, I conducted several experiments to see what would happen when a 45-g, 42.8-mm diameter golf ball bounced on: (a) a 58-mm diameter, 103-g Super Ball®; (b) an 8-mm thick, 56-mm diameter circular disk of Super Ball material cut from a large Super Ball and glued to a 3.4-kg lead brick; and (c) a 3-mm thick sheet of rubber glued to a 3.4-kg lead brick. (See Fig. 1.)

  8. Rotary Valve FY 2016 Highlights

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fitsos, P.

    The fiscal year started with the Rotary Valve (RV) being reassembled after having crashed in June of 2015. The crash occurred when the RV inner surface contacted the housing. The cause of the crash was never confirmed. No particles were found in the 2.5 thousandths of an inch gap and the filters the helium gas passed through were all clean. There were marks on the bearings that looked like electrostatic discharge as shown below in Figure 1. These marks hadn’t been seen before and there were similar discharge marks on some of the ball bearings. Examples of this were foundmore » in a literature search of bearing failures. This leads to a possible cause due to this arcing affecting the rotational accuracy of the bearings driving the RV into the housing.« less

  9. Efficacy of Edwards' Cognitive Shift Approach to Art Education.

    ERIC Educational Resources Information Center

    Chambliss, Catherine A.; Hartl, Alan J.

    1987-01-01

    Noting the lack of experimental evidence substantiating the efficacy of educational strategies designed to exploit the right hemisphere of the brain, a study was designed to assess the cognitive shift model of the Edwards' training procedure. Results showed no difference between the Edwards' procedure and a placebo procedure. Implications for the…

  10. Ball Collision Experiments

    ERIC Educational Resources Information Center

    Cross, R.

    2015-01-01

    Experiments are described on collisions between two billiard balls and between a bat and a ball. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.

  11. Stress Analysis of Transcatheter Aortic Valve Leaflets Under Dynamic Loading: Effect of Reduced Tissue Thickness.

    PubMed

    Abbasi, Mostafa; Azadani, Ali N

    2017-07-01

    In order to accommodate transcatheter valves to miniaturized catheters, the leaflet thickness must be reduced to a value which is typically less than that of surgical bioprostheses. The study aim was to use finite-element simulations to determine the impact of the thickness reduction on stress and strain distribution. A 23 mm transcatheter aortic valve (TAV) was modelled based on the Edwards SAPIEN XT (Edwards Lifesciences, Irvine, CA, USA). Finite-element (FE) analysis was performed using the ABAQUS/Explicit solver. An ensemble-averaged transvalvular pressure waveform measured from in-vitro tests conducted in a pulse duplicator was applied to the leaflets. Through a parametric study, uniform TAV leaflet thickness was reduced from 0.5 to 0.18 mm. By reducing leaflet thickness, significantly higher stress values were found in the leaflet's fixed edge during systole, and in the commissures during diastole. Through dynamic FE simulations, the highest stress values were found during systole in the leaflet fixed edge. In contrast, at the peak of diastole high-stress regions were mainly observed in the commissures. The peak stress was increased by 178% and 507% within the leaflets after reducing the thickness of 0.5 mm to 0.18 mm at the peak of systole and diastole, respectively. The study results indicated that, the smaller the leaflet thickness, the higher the maximum principal stress. Increased mechanical stress on TAV leaflets may lead to accelerated tissue degeneration. By using a thinner leaflet, TAV durability may not atch with that of surgical bioprostheses.

  12. Flow in prosthetic heart valves: state-of-the-art and future directions.

    PubMed

    Yoganathan, Ajit P; Chandran, K B; Sotiropoulos, Fotis

    2005-12-01

    Since the first successful implantation of a prosthetic heart valve four decades ago, over 50 different designs have been developed including both mechanical and bioprosthetic valves. Today, the most widely implanted design is the mechanical bileaflet, with over 170,000 implants worldwide each year. Several different mechanical valves are currently available and many of them have good bulk forward flow hemodynamics, with lower transvalvular pressure drops, larger effective orifice areas, and fewer regions of forward flow stasis than their earlier-generation counterparts such as the ball-and-cage and tilting-disc valves. However, mechanical valve implants suffer from complications resulting from thrombus deposition and patients implanted with these valves need to be under long-term anti-coagulant therapy. In general, blood thinners are not needed with bioprosthetic implants, but tissue valves suffer from structural failure with, an average life-time of 10-12 years, before replacement is needed. Flow-induced stresses on the formed elements in blood have been implicated in thrombus initiation within the mechanical valve prostheses. Regions of stress concentration on the leaflets during the complex motion of the leaflets have been implicated with structural failure of the leaflets with bioprosthetic valves. In vivo and in vitro experimental studies have yielded valuable information on the relationship between hemodynamic stresses and the problems associated with the implants. More recently, Computational Fluid Dynamics (CFD) has emerged as a promising tool, which, alongside experimentation, can yield insights of unprecedented detail into the hemodynamics of prosthetic heart valves. For CFD to realize its full potential, however, it must rely on numerical techniques that can handle the enormous geometrical complexities of prosthetic devices with spatial and temporal resolution sufficiently high to accurately capture all hemodynamically relevant scales of motion. Such

  13. Aerodynamics of sports balls

    NASA Astrophysics Data System (ADS)

    Mehta, R. D.

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  14. Aerodynamics of sports balls

    NASA Technical Reports Server (NTRS)

    Mehta, R. D.

    1985-01-01

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  15. Ground winds and winds aloft for Edwards AFB, California (1978 revision)

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Brown, S. C.

    1978-01-01

    Ground level runway wind statistics for the Edwards AFB, California area are presented. Crosswind, headwind, tailwind, and headwind reversal percentage frequencies are given with respect to month and hour for the two major Edwards AFB runways. Also presented are Edwards AFB bivariate normal wind statistics for a 90 degree flight azimuth for altitudes 0 through 27 km. Wind probability distributions and statistics for any rotation of axes can be computed from the five given parameters.

  16. Robert Edwards: the path to IVF☆

    PubMed Central

    Johnson, Martin H

    2011-01-01

    The early influences on Robert Edwards’ approach to the scientific research that led to human IVF are described. His interest as a graduate student in the genetics of early mammalian development stimulated him later to investigate whether the origins of human genetic diseases such as Down, Klinefelter and Turner syndromes might be explained by events during egg maturation. This clinical problem provided the most powerful stimulus to achieve both oocyte maturation and fertilization in vitro in humans. Indeed, preimplantation genetic diagnosis was his main goal until he met Patrick Steptoe in 1968. A re-evaluation of his meeting with Steptoe suggests that initially Steptoe’s laparoscopic skill was of interest for its potential to solve the sperm capacitation problem. Steptoe’s impact on Edwards was twofold. First, Steptoe’s long-held interest in infertility raised this application of IVF higher in Edwards’ priorities. Second, Steptoe offered a long-term partnership, in which oocyte collection without in-vitro maturation was a possibility. The professional criticism generated by their work together encouraged Edwards to pursue a deliberate programme of public education about the issues raised and to challenge and develop professional bioethical thought and discourse about reproduction. The early life and career of Robert Edwards are described and re-evaluated in the light of documentary evidence. His early interest in the genetics of development provided the major motivation behind his goal of achieving IVF in humans. Through this work, he aimed to understand and hopefully to reduce the transmission of genetic disease in humans. His meeting with Patrick Steptoe, the details of which are re-examined, increased the significance for Edwards of infertility as an outcome of IVF. It also led to a creative long-term research partnership, initiated a long-term programme of public education in the UK about reproductive science and stimulated the development of

  17. Trans-apical aortic valve implantation using a new self-expandable bioprosthesis: initial outcomes.

    PubMed

    Kempfert, Jörg; Rastan, Ardawan J; Beyersdorf, Friedhelm; Schönburg, Markus; Schuler, Gerhard; Sorg, Stefan; Mohr, Friedrich-W; Walther, Thomas

    2011-11-01

    Trans-apical aortic valve implantation (TA-AVI) has evolved into a standard approach for high-risk, elderly patients using the balloon-expandable Edwards SAPIEN™ prosthesis. As an alternative device, a self-expanding sub-coronary trans-apical bioprosthesis was evaluated. The Symetis Acurate™ trans-catheter heart valve is composed of a porcine biologic valve attached to a self-expandable nitinol stent. It allows for anatomical orientation, and facilitates intuitive implantation providing tactile feedback. Three valves sizes were available to treat patients with an annular diameter between 21 and 27mm. Since November 2009, a total of 40 patients have been treated at three sites. Patient age was 82.8±4 years, 60% were female, logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) was 21.5±10.9% and Society of Thoracic Surgeons (STS) Score was 9.0±4.6%. All implants were delivered successfully in the intra-annular and sub-coronary position off pump. One patient was converted to conventional surgery due to coronary impingement; post-dilatation was performed in 45% of patients; and two patients required the SAPIEN™ valve in valve implantation. Echocardiographic and angiographic control revealed no/trivial aortic incompetence (AI) in 59%, mild AI in 33.3%, and moderate AI in 7.7% of the patients. Three patients died within 30 days from a non-valve-related cause (respiratory), the patient converted did not recover from right-heart failure, and one patient died on day 19 due to unclear reasons. There was one incidence of new-onset atrioventricular (AV) block requiring pacemaker implantation. Two patients suffered a stroke (one secondary and the other intraprocedural). Transvalvular gradients were maximum 29.4±10.7mmHg and mean 14.3±6.8mmHg. The initial clinical results indicate a relatively straightforward implantation procedure and good functional results after trans-apical implantation of the Symetis Acurate™ device. Copyright © 2011

  18. Effect of Practicing Soccer Juggling With Different Sized Balls Upon Performance, Retention, and Transfer to Ball Reception.

    PubMed

    Raastad, Olav; Aune, Tore Kristian; van den Tillaar, Roland

    2016-10-01

    The aim of this study was to investigate if making the skill acquisition phase more difficult or easier would enhance performance in soccer juggling, and if this practice has a positive intertask transfer effect to ball reception performance. Twenty-two adolescent soccer players were tested in juggling a soccer ball and in the control of an approaching ball at a pre, post and retention test. The participants were randomly divided in a small ball size and bigger ball size training group that both trained four times per week for 6 weeks. At the post and retention test both groups enhanced performance in soccer juggling test with no difference between groups and no increase in ball reception performance at these tests. It was concluded that about intra task transfer and retention of soccer juggling skills, it does not matter if you increase (small balls) or decrease the difficulty (larger balls) when using the same amount of practice time within the skill acquisition phase in soccer juggling. In addition that for ball juggling and ball reception (inter task) these two tasks differ too much in afferent information and movement characteristics that no positive transfer between these two skills no positive intertask transfer can be expected.

  19. Tailored prolapse surgery for the treatment of hemorrhoids with a new dedicated device: TST Starr plus.

    PubMed

    Naldini, G; Fabiani, B; Menconi, C; Giani, I; Toniolo, G; Martellucci, J

    2015-12-01

    The aim of the study was to assess the results of the stapled transanal procedure in the treatment of hemorrhoidal prolapse in terms of postoperative complications and recurrence rate using a new dedicated device, TST Starr plus. Patients affected by III-IV degree hemorrhoidal prolapsed that underwent stapled transanal resection with the TST Starr plus were included in the present study. Results of the procedure with perioperative complications, postoperative complications, and recurrence rate were reported. From November 2012 to October 2014, 52 patients (19 females) were enrolled in the study. The main symptoms were prolapse (100 %) and bleeding (28.8 %). Transanal rectal resection was performed with parachute technique in 24 patients (46.2 %) and purse string technique in 23 patients (53.8 %). A mild hematoma at the suture line occurred in one patient (1.9 %). Postoperative bleeding was reported in three patients (5.7 %), in one of which, reoperation was necessary (1.9 %). Tenesmus occurred in one patient (1.9 %), and it was resolved with medical therapy. Urgency was reported in nine patients (17.1 %) at 7 days after surgery. Of these, three patients (5.7 %) complained urgency at the median follow-up of 14.5 months. Reoperation was performed in one patient (1.9 %) for chronic anal pain for rigid suture fixed on the deep plans. Occasional bleeding was reported in four patients (7.7 %). No recurrence of prolapse was reported at a median of 14.5 months after surgery, even if one patient (1.9 %) had a partial recurrent prolapse of a downstaged single pile. TST Starr plus seems to be safe and effective for a tailored transanal stapled surgery for the treatment of III-IV degree hemorrhoidal prolapse. The new conformation and innovative technology of the stapler seems to reduce some postoperative complications and recurrence rate.

  20. Transcatheter aortic valve-in-valve implantation of a CoreValve in a JenaValve prosthesis: a case report.

    PubMed

    Lotfi, Shahram; Becker, Michael; Moza, Ajay; Autschbach, Rüdiger; Marx, Nikolaus; Schröder, Jörg

    2017-09-10

    Transcatheter aortic valve implantation has become an accepted treatment modality for inoperable or high-risk surgical patients with symptomatic severe aortic stenosis. We report the case of a 70-year-old white man who was treated for severe symptomatic aortic regurgitation using transcatheter aortic valve implantation from the apical approach. Because of recurrent cardiac decompensation 4 weeks after implantation he underwent the implantation of a left ventricular assist device system. A year later echocardiography showed a severe transvalvular central insufficiency. Our heart team decided to choose a valve-in-valve approach while reducing the flow rate of left ventricular assist device to minimum and pacing with a frequency of 140 beats/minute. There was an excellent result and our patient is doing well with no relevant insufficiency of the aortic valve at 12-month follow-up. This is the first report about a successful treatment of a stenotic JenaValve using a CoreValve Evolut R; the use of a CoreValve Evolut R prosthesis may be an optimal option for valve-in-valve procedures.

  1. Experimental evaluation of 150-millimeter bore ball bearing to 3 million DN using either solid or drilled balls

    NASA Technical Reports Server (NTRS)

    Scibbe, H. W.; Munson, H. E.

    1973-01-01

    Seven 150-mm bore ball bearings were run under 8900 Newton (2000 lb) thrust load at speeds from 6670 to 20,000 rpm (1 to 3 million DN). Four of the bearings had conventional solid balls and three bearing had drilled (cylindrically hollow) balls with 50 percent mass reduction. The bearings were under-race cooled and slot-lubricated with Type 2 ester oil at flow rates from 4.35 to 5.80 liters per minute (1.15 to 1.57 gal min). Friction torque and temperatures were measured on all bearings. No significant difference in torque was noted, between the solid and drilled ball bearings. One bearing of each type was rerun at 17,800 Newtons (4000 lb) thrust load. The solid ball bearings performed satisfactorily at 3 million DN. However, at about 2 million DN the drilled ball bearing experienced a broken ball and cracks appeared in two other balls as the result of flexure fatigue. Metallurgical examination of the cracked balls indicated a brittle structure in the bore of the drilled balls.

  2. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2007-01-01

    The article offers information on ball clay. Among the companies that mine ball clay in the U.S. are H.C. Spinks Clay, Kentucky-Tennessee Clay and Old Hickory Clay. In 2006, an estimated 1.2 million tons of the mineral was sold or used domestically and exported. Forty-percent of the total sales is accounted for ceramic floor and wall tile followed by sanitaryware and miscellaneous ceramics. Its average value was $ 45 per ton in 2006.

  3. Edward Said and "Orientalism"

    ERIC Educational Resources Information Center

    Chronicle of Higher Education, 2007

    2007-01-01

    In the nearly 30 years since Edward Said published the hugely influential Orientalism, his indictment of racism and imperialism in Western scholarship on the Orient has had its share of plaudits and condemnations. Now Robert Irwin, the Middle East editor of The Times Literary Supplement, has reignited the controversy with his broadside against the…

  4. The challenge of valve-in-valve procedures in degenerated Mitroflow bioprostheses and the advantage of using the JenaValve transcatheter heart valve.

    PubMed

    Conradi, Lenard; Kloth, Benjamin; Seiffert, Moritz; Schirmer, Johannes; Koschyk, Dietmar; Blankenberg, Stefan; Reichenspurner, Hermann; Diemert, Patrick; Treede, Hendrik

    2014-12-01

    Recently, the feasibility of valve-in-valve procedures using current first-generation transcatheter heart valves (THV) in cases of structural valve degeneration has been reported as an alternative to conventional open repeat valve replacement. By design, certain biological valve xenografts carry a high risk of coronary ostia occlusion due to lateral displacement of leaflets after valve-in-valve procedures. In the present report we aimed to prove feasibility and safety of transapical valve-in-valve implantation of the JenaValve THV in two cases of degenerated Mitroflow bioprostheses. We herein report two cases of successful transapical valve-in-valve procedures using a JenaValve THV implanted in Sorin Mitroflow bioprostheses for structural valve degeneration. Both patients were alive and in good clinical condition at 30 days from the procedure. However, increased transvalvular gradients were noted in both cases. Transcatheter valve-in-valve implantation of a JenaValve THV is a valid alternative for patients with degenerated Mitroflow bioprostheses of sufficient size and in the presence of short distances to the coronary ostia who are too ill for conventional repeat open heart surgery. Increased pressure gradients have to be expected and weighed against the disadvantages of other treatment options when planning such a procedure.

  5. Geologic framework and hydrogeologic characteristics of the Edwards Aquifer outcrop, Medina County, Texas

    USGS Publications Warehouse

    Small, Ted A.; Clark, Allan K.

    2000-01-01

    The hydrogeologic subdivisions of the Edwards aquifer outcrop in Medina County generally are porous and permeable. The most porous and permeable appear to be hydrogeologic subdivision VI, the Kirschberg evaporite member of the Kainer Formation; and hydrogeologic subdivision III, the leached and collapsed members, undivided, of the Person Formation. The most porous and permeable rocks of the Devils River Formation in Medina County appear to be in the top layer. The upper member of the Glen Rose Limestone, the lower confining unit, has much less porosity and permeability than that observed in the Edwards aquifer.The Edwards aquifer has relatively large porosity and permeability resulting, in part, from the development or redistribution of secondary porosity. Lithology, stratigraphy, diagenesis, and karstification account for the effective porosity and permeability in the Edwards aquifer outcrop. Karst features that can greatly enhance effective porosity and permeability in the Edwards aquifer outcrop include sinkholes, dolines, and caves. The Edwards aquifer rocks in Medina County change from the eight-member Edwards Group to the essentially indivisible Devils River Formation. The facies change occurs along a line extending northwestward from just south of Medina Lake.

  6. Searching for Solar System Wide Binaries with Pan-STARRS-1

    NASA Astrophysics Data System (ADS)

    Holman, Matthew J.; Protopapas, P.; Tholen, D. J.

    2007-10-01

    Roughly 60% of the observing time of the Pan-STARRS-1 (PS1) telescope will be dedicated to a "3pi steradian" survey with an observing cadence that is designed for the detection of near-Earth asteroids and slow-moving solar system bodies. Over this course of its 3.5 year cience mission, this unprecedented survey will discover nearly every asteroid, Trojan, Centaur, long-period comet, short-period comet, and trans-neptunian object (TNO) brighter than magnitude R=23. This census will be used to address a large number of questions regarding the physical and dynamical properties of the various small body populations of the solar system. Roughly 1-2% of TNOs are wide binaries with companions at separations greater than 1 arcsec and brightness differences less than 2 magnitudes (Kern & Elliot 2006; Noll et al 2007). These can be readily detected by PS1; we will carry out such a search with PS1 data. To do so, we will modify the Pan-STARRS Moving Object Processing System (MOPS) such that it will associate the components of resolved or marginally resolved binaries, link such pairs of detections obtained at different epochs, and the estimate the relative orbit of the binary. We will also determine the efficiency with which such binaries are detected as a function of the binary's relative orbit and the relative magnitudes of the components. Based on an estimated 7000 TNOs that PS1 will discover, we anticipate finding 70-140 wide binaries. The PS1 data, 60 epochs over three years, is naturally suited to determining the orbits of these objects. Our search will accurately determine the binary fraction for a variety of subclasses of TNOs.

  7. Ball motion and sliding friction in an arched outer-race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1974-01-01

    The motion of the ball and sliding friction in an arched outer-race ball bearing under thrust load is analyzed. Fatigue life evaluations were made. The analysis is applied to a 150-millimeter-bore ball bearing. The results indicated that for high-speed light-load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be optimal. Also, for an arched bearing a considerable amount of spinning occurs at the outer-race contacts.

  8. Valve Health Monitoring System Utilizing Smart Instrumentation

    NASA Technical Reports Server (NTRS)

    Jensen, Scott L.; Drouant, George J.

    2006-01-01

    The valve monitoring system is a stand alone unit with network capabilities for integration into a higher level health management system. The system is designed for aiding in failure predictions of high-geared ball valves and linearly actuated valves. It performs data tracking and archiving for identifying degraded performance. The data collection types are cryogenic cycles, total cycles, inlet temperature, body temperature torsional strain, linear bonnet strain, preload position, total travel and total directional changes. Events are recorded and time stamped in accordance with the IRIG B True Time. The monitoring system is designed for use in a Class 1 Division II explosive environment. The basic configuration consists of several instrumentation sensor units and a base station. The sensor units are self contained microprocessor controlled and remotely mountable in three by three by two inches. Each unit is potted in a fire retardant substance without any cavities and limited to low operating power for maintaining safe operation in a hydrogen environment. The units are temperature monitored to safeguard against operation outside temperature limitations. Each contains 902-928 MHz band digital transmitters which meet Federal Communication Commission's requirements and are limited to a 35 foot transmission radius for preserving data security. The base-station controller correlates data from the sensor units and generates data event logs on a compact flash memory module for database uploading. The entries are also broadcast over an Ethernet network. Nitrogen purged National Electrical Manufactures Association (NEMA) Class 4 enclosures are used to house the base-station

  9. Valve health monitoring system utilizing smart instrumentation

    NASA Astrophysics Data System (ADS)

    Jensen, Scott L.; Drouant, George J.

    2006-05-01

    The valve monitoring system is a stand alone unit with network capabilities for integration into a higher level health management system. The system is designed for aiding in failure predictions of high-geared ball valves and linearly actuated valves. It performs data tracking and archiving for identifying degraded performance. The data collection types are: cryogenic cycles, total cycles, inlet temperature, outlet temperature, body temperature, torsional strain, linear bonnet strain, preload position, total travel, and total directional changes. Events are recorded and time stamped in accordance with the IRIG B True Time. The monitoring system is designed for use in a Class 1 Division II explosive environment. The basic configuration consists of several instrumentation sensor units and a base station. The sensor units are self contained microprocessor controlled and remotely mountable in three by three by two inches. Each unit is potted in a fire retardant substance without any cavities and limited to low operating power for maintaining safe operation in a hydrogen environment. The units are temperature monitored to safeguard against operation outside temperature limitations. Each contains 902-928 MHz band digital transmitters which meet Federal Communication Commissions requirements and are limited to a 35 foot transmission radius for preserving data security. The base-station controller correlates related data from the sensor units and generates data event logs on a compact flash memory module for database uploading. The entries are also broadcast over an Ethernet network. Nitrogen purged National Electrical Manufactures Association (NEMA) Class 4 Enclosures are used to house the base-station.

  10. Telescoping magnetic ball bar test gage

    DOEpatents

    Bryan, J.B.

    1984-03-13

    A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengageable servo drives which cannot be clutched out is disclosed. Two gage balls are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit and a rigid member. One gage ball is secured by a magnetic socket knuckle assembly which fixes its center with respect to the machine being tested. The other gage ball is secured by another magnetic socket knuckle assembly which is engaged or held by the machine in such manner that the center of that ball is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball. As the moving ball executes its trajectory, changes in the radial distance between the centers of the two balls caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly actuated by the parallel reed flexure unit. Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball locations, thereby determining the accuracy of the machine. 3 figs.

  11. Telescoping magnetic ball bar test gage

    DOEpatents

    Bryan, J.B.

    1982-03-15

    A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengagable servo drives which cannot be clutched out. Two gage balls are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit and a rigid member. One gage ball is secured by a magnetic socket knuckle assembly which fixes its center with respect to the machine being tested. The other gage ball is secured by another magnetic socket knuckle assembly which is engaged or held by the machine in such manner that the center of that ball is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball. As the moving ball executes its trajectory, changes in the radial distance between the centers of the two balls caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly actuated by the parallel reed flexure unit. Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball locations, thereby determining the accuracy of the machine.

  12. Determinants of image quality of rotational angiography for on-line assessment of frame geometry after transcatheter aortic valve implantation.

    PubMed

    Rodríguez-Olivares, Ramón; El Faquir, Nahid; Rahhab, Zouhair; Maugenest, Anne-Marie; Van Mieghem, Nicolas M; Schultz, Carl; Lauritsch, Guenter; de Jaegere, Peter P T

    2016-07-01

    To study the determinants of image quality of rotational angiography using dedicated research prototype software for motion compensation without rapid ventricular pacing after the implantation of four commercially available catheter-based valves. Prospective observational study including 179 consecutive patients who underwent transcatheter aortic valve implantation (TAVI) with either the Medtronic CoreValve (MCS), Edward-SAPIEN Valve (ESV), Boston Sadra Lotus (BSL) or Saint-Jude Portico Valve (SJP) in whom rotational angiography (R-angio) with motion compensation 3D image reconstruction was performed. Image quality was evaluated from grade 1 (excellent image quality) to grade 5 (strongly degraded). Distinction was made between good (grades 1, 2) and poor image quality (grades 3-5). Clinical (gender, body mass index, Agatston score, heart rate and rhythm, artifacts), procedural (valve type) and technical variables (isocentricity) were related with the image quality assessment. Image quality was good in 128 (72 %) and poor in 51 (28 %) patients. By univariable analysis only valve type (BSL) and the presence of an artefact negatively affected image quality. By multivariate analysis (in which BMI was forced into the model) BSL valve (Odds 3.5, 95 % CI [1.3-9.6], p = 0.02), presence of an artifact (Odds 2.5, 95 % CI [1.2-5.4], p = 0.02) and BMI (Odds 1.1, 95 % CI [1.0-1.2], p = 0.04) were independent predictors of poor image quality. Rotational angiography with motion compensation 3D image reconstruction using a dedicated research prototype software offers good image quality for the evaluation of frame geometry after TAVI in the majority of patients. Valve type, presence of artifacts and higher BMI negatively affect image quality.

  13. Safety valve

    DOEpatents

    Bergman, Ulf C.

    1984-01-01

    The safety valve contains a resilient gland to be held between a valve seat and a valve member and is secured to the valve member by a sleeve surrounding the end of the valve member adjacent to the valve seat. The sleeve is movable relative to the valve member through a limited axial distance and a gap exists between said valve member and said sleeve.

  14. Occasional Addresses by Edward Teller at Conferences of Laser Interaction and Related Plasma Phenomena (LIRPP)

    NASA Astrophysics Data System (ADS)

    Hora, Heinrich; Miley, George H.

    2016-10-01

    The following sections are included: * Futurology of High Intensity Lasers (LIRPP Vol. 3A) * Lecture in Connection with the Edward Teller Medal Award (LIRPP Vol. 10) * Photo of the First Recipients of the Edward Teller Medal in 1991 * Photos from the Edward Teller Medal Celebration in 1997 * Photo with Participants of the LIRPP No. 12 Conference, 1995 * Photo with Edward Teller Medalists at IFSA01, Kyoto, 2001 * Keynote Address: The Edward Teller Lecture (LIRPP Vol. 11) * Keynote Address: Dr. Edward Teller (LIRPP Vol. 12) * Teller Award Presentation and Keynote Address (LIRPP Vol. 13) * Laudations of Awardees 1991-1995 (LIRPP Vol. 13) * Laudations of Awardees 1999-2003

  15. IVF endocrinology: the Edwards era.

    PubMed

    Hillier, Stephen G

    2013-12-01

    Through pioneering human IVF as a global infertility treatment, Robert Edwards and his clinical partner Patrick Steptoe launched the field of IVF endocrinology. Following repeated failures with oocytes collected in human menopausal gonadotrophin (HMG) primed cycles timed to injection of human chorionic gonadotrophin (HCG), the first successful IVF pregnancy came from a spontaneous menstrual cycle. Intensive endocrine monitoring was used to track pre-ovulatory follicular development and collect a single ripe egg timed to the natural LH surge. Despite this groundbreaking achievement, ovulation induction was clearly required to make IVF treatment clinically robust and reliable. Ovarian stimulation with clomiphene citrate was used to achieve the first maternity from a superovulated human IVF cycle in 1980. HMG/HCG regimens were then successfully introduced-including substitution of 'pure' follicle-stimulating hormone as the principal ovarian stimulant. The application and success of IVF treatment were dramatically enhanced by the introduction of gonadotrophin-releasing hormone analogues that enabled elective control of endogenous gonadotrophin release during ovarian stimulation. Programmed gonadotrophin regimes yielding double-digit oocyte numbers became normal: 'more is better' was the ethos. Bob Edwards expressed increasing concern over the cost, complexity and potential long-term health risks of such high-order ovarian stimulation. In later life he repeatedly called for a return to minimalist approaches based on the natural menstrual cycle to improve oocyte quality over quantity. This article reviews the application of ovulation induction to human IVF and celebrates Edwards' abiding impact on the field, which firmly grounds him in the reproductive endocrinology pantheon.

  16. The Goldenrod Ball Gall

    ERIC Educational Resources Information Center

    Fischer, Richard B.

    1974-01-01

    The paper presents a generalized life history of the goldenrod ball gall, a ball-shaped swelling found almost exclusively on the Canada goldenrod, Solidago canadensis, and caused by a peacock fly know as Eurosta soldiaginis. (KM)

  17. Ball motion and sliding friction in an arched outer race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1973-01-01

    The motion of the ball and sliding friction in an arched outer race ball bearing under thrust loads is determined. Fatigue life evaluations were made. The analysis is applied to a 150 millimeter bore ball bearing. The results indicated that for high speed-light load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be an optimal. For an arched bearing it was also found that a considerable amount of spinning occurs at the outer race contacts.

  18. Ball motion and sliding friction in an arched outer race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1974-01-01

    The motion of the ball and sliding friction in an arched outer-race ball bearing under thrust load is determined. Fatigue life evaluations were made. The analysis is applied to a 150 millimeter bore ball bearing. The results indicated that for high speed-light load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be an optimal. For an arched bearing it was also found that a considerable amount of spinning occurs at the outer race contacts.

  19. A second prosthesis as a procedural rescue option in trans-apical aortic valve implantation.

    PubMed

    Kempfert, Jörg; Rastan, Ardawan J; Schuler, Gerhard; Linke, Axel; Holzhey, David; van Linden, Arnaud; Mohr, Friedrich-W; Walther, Thomas

    2011-07-01

    Trans-apical aortic valve implantation (TA-AVI) using the Edwards SAPIEN™ prosthesis has evolved to a routine procedure for selected high-risk elderly patients. In rare cases, misplacement of the SAPIEN™ valve (too low a position), dysfunction of the leaflets or perforation of the interventricular septum (ventricular septal defect, VSD) occurs and requires immediate implantation of a second prosthesis within the first one. Results of this 'bailout' maneuver have not been reported yet. Of 305 TA-AVI procedures, 15 patients required a second prosthesis due to dysfunctional leaflets (n = 6), low position (n = 7), or VSD (n = 2). Mean age was 82.5 ± 1.3 years, mean logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) was 45.5 ± 5.4, and Society of Thoracic Surgeons (STS) Score was 13.5 ± 1.5. All second SAPIEN™ valves could be implanted successfully within the first one. The second prosthesis solved leaflet dysfunction, sealed the VSD (lower position of the second prosthesis), or corrected the initial misplacement (higher position of the second prosthesis) in all patients. Within 30 days, four patients died (low cardiac output n = 3, all with preoperative ejection fraction (EF) <35%; intestinal ischemia n = 1). Intra-operative echocardiogram and angiogram revealed mild paravalvular leak in three and none/trace in 12 patients. Transvalvular gradients were low despite the implantation of the second valve (P(max)/mean 13.7 ± 4.3/6.4 ± 2.0). Placement of a second SAPIEN™ valve is a valuable 'bailout' technique in case of VSD, dysfunctional leaflets, or too low placement of the first prosthesis. The technique leads to an excellent functional result with low transvalvular gradients. The simple, straight, tubular stent design of the SAPIEN™ prosthesis may be the ideal design for such valve-in-valve procedures. Copyright © 2011 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

  20. Fluid Mechanics of Cricket and Tennis Balls

    NASA Astrophysics Data System (ADS)

    Mehta, Rabindra D.

    2009-11-01

    Aerodynamics plays a prominent role in defining the flight of a ball that is struck or thrown through the air in almost all ball sports. The main interest is in the fact that the ball can often deviate from its initial straight path, resulting in a curved, or sometimes an unpredictable, flight path. It is particularly fascinating that that not all the parameters that affect the flight of a ball are always under human influence. Lateral deflection in flight, commonly known as swing, swerve or curve, is well recognized in cricket and tennis. In tennis, the lateral deflection is produced by spinning the ball about an axis perpendicular to the line of flight, which gives rise to what is commonly known as the Magnus effect. It is now well recognized that the aerodynamics of sports balls are strongly dependent on the detailed development and behavior of the boundary layer on the ball's surface. A side force, which makes a ball curve through the air, can also be generated in the absence of the Magnus effect. In one of the cricket deliveries, the ball is released with the seam angled, which trips the laminar boundary layer into a turbulent state on that side. The turbulent boundary layer separates relatively late compared to the laminar layer on the other side, thereby creating a pressure difference and hence side force. The fluid mechanics of a cricket ball become very interesting at the higher Reynolds numbers and this will be discussed in detail. Of all the round sports balls, a tennis ball has the highest drag coefficient. This will be explained in terms of the contribution of the ``fuzz" drag and how that changes with Reynolds number and ball surface wear. It is particularly fascinating that, purely through historical accidents, small disturbances on the ball surface, such as the stitching on cricket balls and the felt cover on tennis balls are all about the right size to affect boundary layer transition and development in the Reynolds numbers of interest. The fluid

  1. Fracturing mechanics before valve-in-valve therapy of small aortic bioprosthetic heart valves.

    PubMed

    Johansen, Peter; Engholt, Henrik; Tang, Mariann; Nybo, Rasmus F; Rasmussen, Per D; Nielsen-Kudsk, Jens Erik

    2017-10-13

    Patients with degraded bioprosthetic heart valves (BHV) who are not candidates for valve replacement may benefit from transcatheter valve-in-valve (VIV) therapy. However, in smaller-sized surgical BHV the resultant orifice may become too narrow. To overcome this, the valve frame can be fractured by a high-pressure balloon prior to VIV. However, knowledge on fracture pressures and mechanics are prerequisites. The aim of this study was to identify the fracture pressures needed in BHV, and to describe the fracture mechanics. Commonly used BHV of small sizes were mounted on a high-pressure balloon situated in a biplane fluoroscopic system with a high-speed camera. The instant of fracture was captured along with the balloon pressure. The valves were inspected for material protrusion and later dissected for fracture zone investigation and description. The valves with a polymer frame fractured at a lower pressure (8-10 atm) than those with a metal stent (19-26 atm). None of the fractured valves had elements protruding. VIV procedures in small-sized BHV may be performed after prior fracture of the valve frame by high-pressure balloon dilatation. This study provides tentative guidelines for expected balloon sizes and pressures for valve fracturing.

  2. Enhancing the Bounce of a Ball

    ERIC Educational Resources Information Center

    Cross, Rod

    2010-01-01

    In sports such as baseball, softball, golf, and tennis, a common objective is to hit the ball as fast or as far as possible. Another common objective is to hit the ball so that it spins as fast as possible, since the trajectory of the ball through the air is strongly affected by ball spin. In an attempt to enhance both the coefficient of…

  3. Water production in comets C/2011 L4 (PanSTARRS) and C/2012 F6 (Lemmon) from observations with Soho/Swan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Combi, M. R.; Aptekar, G.; Bertaux, J.-L.

    2014-06-01

    Comets C/2011 L4 (PanSTARRS) and C/2012 F6 (Lemmon) were observed throughout their 2012-2013 apparitions with the Solar Wind Anisotropies (SWAN) all-sky hydrogen Lyα camera on board the Solar and Heliosphere Observatory (SOHO) satellite. SOHO has been in a halo orbit around the L1 Earth-Sun Lagrange point since early 1996 and has been observing the interplanetary medium and comets beginning with C/1996 B2 (Hyakutake). The global water production from these comets was determined from an analysis of the SWAN Lyα camera observations. Comet C/2011 L4 (PanSTARRS), which reached its perihelion distance of 0.302 AU on 2013 March 10.17, was observed onmore » 50 days between 2013 January 29 and April 30. Comet C/2012 F6 (Lemmon), which reached its perihelion distance of 0.731 AU on 2013 March 24.51, was observed on 109 days between 2012 November 29 and 2013 June 31. The maximum water production rates were ∼1 × 10{sup 30} molecules s{sup –1} for both comets. The activities of both comets were asymmetric about perihelion. C/2011 L4 (PanSTARRS) was more active before perihelion than after, but C/2012 F6 (Lemmon) was more active after perihelion than before.« less

  4. Clinical Outcomes Following Transcatheter Aortic Valve Replacement in Asian Population.

    PubMed

    Yoon, Sung-Han; Ahn, Jung-Min; Hayashida, Kentaro; Watanabe, Yusuke; Shirai, Shinichi; Kao, Hsien-Li; Yin, Wei-Hsian; Lee, Michael Kang-Yin; Tay, Edgar; Araki, Motoharu; Yamanaka, Futoshi; Arai, Takahide; Lin, Mao-Shin; Park, Jun-Bean; Park, Duk-Woo; Kang, Soo-Jin; Lee, Seung-Whan; Kim, Young-Hak; Lee, Cheol Whan; Park, Seong-Wook; Muramatsu, Toshiya; Hanyu, Michiya; Kozuma, Ken; Kim, Hyo-Soo; Saito, Shigeru; Park, Seung-Jung

    2016-05-09

    This study describes the characteristics of a real-world Asian patient population treated with transcatheter aortic valve replacement (TAVR) and evaluates their clinical outcomes. No previously reported randomized or observational studies adequately assess the safety and efficacy of TAVR in an Asian population. The Asian TAVR registry is an international multicenter study that enrolled patients with aortic stenosis who underwent TAVR in Asian countries. In total, 848 patients with mean STS score of 5.2 ± 3.8% were enrolled between March 2010 and September 2014 at 11 centers in 5 countries. The Edwards Sapien or Medtronic CoreValve was implanted in 64.7% and 35.3% of patients, respectively. The procedural success rate was 97.5%. The 30-day and 1-year mortality rates were 2.5% and 10.8%, respectively. There was no difference in 1-year mortality between devices (Sapien: 9.4%; CoreValve: 12.2%; log-rank p = 0.40). The rates of stroke, life-threatening bleeding, major vascular complications and acute kidney injury (stage 2 to 3) were 3.8%, 6.4%, 5.0% and 3.3%, respectively. Moderate or severe paravalvular leakage was significantly more common with the CoreValve than Sapien (14.4% vs. 7.3%; p = 0.001). According to the multivariate model, a higher STS score, lower body mass index, New York Heart Association functional class III-IV symptoms, diabetes mellitus, prior cerebrovascular accident, low mean gradient at baseline, and moderate or severe paravalvular leakage were significantly associated with reduced survival. Despite anatomical features of concern, the clinical outcomes of TAVR in our Asian population were favorable in comparison with those of previously published trials and observational studies. (The Asian Transcatheter Aortic Valve Replacement Registry [Asian TAVR]; NCT02308150). Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  5. Geohydrologic Framework of the Edwards and Trinity Aquifers, South-Central Texas

    USGS Publications Warehouse

    Blome, Charles D.; Faith, Jason R.; Ozuna, George B.

    2007-01-01

    This five-year USGS project, funded by the National Cooperative Geologic Mapping Program, is using multidisciplinary approaches to reveal the surface and subsurface geologic architecture of two important Texas aquifers: (1) the Edwards aquifer that extends from south of Austin to west of San Antonio and (2) the southern part of the Trinity aquifer in the Texas Hill Country west and south of Austin. The project's principal areas of research include: Geologic Mapping, Geophysical Surveys, Geochronology, Three-dimensional Modeling, and Noble Gas Geochemistry. The Edwards aquifer is one of the most productive carbonate aquifers in the United States. It also has been designated a sole source aquifer by the U.S. Environmental Protection Agency and is the primary source of water for San Antonio, America's eighth largest city. The Trinity aquifer forms the catchment area for the Edwards aquifer and it intercepts some surface flow above the Edwards recharge zone. The Trinity may also contribute to the Edwards water budget by subsurface flow across formation boundaries at considerable depths. Dissolution, karst development, and faulting and fracturing in both aquifers directly control aquifer geometry by compartmentalizing the aquifer and creating unique ground-water flow paths.

  6. Ceramic ball grid array package stress analysis

    NASA Astrophysics Data System (ADS)

    Badri, S. H. B. S.; Aziz, M. H. A.; Ong, N. R.; Sauli, Z.; Alcain, J. B.; Retnasamy, V.

    2017-09-01

    The ball grid array (BGA), a form of chip scale package (CSP), was developed as one of the most advanced surface mount devices, which may be assembled by an ordinary surface ball bumps are used instead of plated nickel and gold (Ni/Au) bumps. Assembly and reliability of the BGA's printed circuit board (PCB), which is soldered by conventional surface mount technology is considered in this study. The Ceramic Ball Grid Array (CBGA) is a rectangular ceramic package or square-shaped that will use the solder ball for external electrical connections instead of leads or wire for connections. The solder balls will be arranged in an array or grid at the bottom of the ceramic package body. In this study, ANSYS software is used to investigate the stress on the package for 2 balls and 4 balls of the CBGA package with the various force range of 1-3 Newton applied to the top of the die, top of the substrate and side of the substrate. The highest maximum stress was analyzed and the maximum equivalent stress was observed on the solder ball and the die. From the simulation result, the CBGA package with less solder balls experience higher stress compared to the package with many solder balls. Therefore, less number of solder ball on the CBGA package results higher stress and critically affect the reliability of the solder balls itself, substrate and die which can lead to the solder crack and also die crack.

  7. The extent of aortic annulus calcification is a predictor of postprocedural eccentricity and paravalvular regurgitation: a pre- and postinterventional cardiac computed tomography angiography study.

    PubMed

    Bekeredjian, Raffi; Bodingbauer, Dorothea; Hofmann, Nina P; Greiner, Sebastian; Schuetz, Moritz; Geis, Nicolas A; Kauczor, Hans U; Bryant, Mark; Chorianopoulos, Emmanuel; Pleger, Sven T; Mereles, Derliz; Katus, Hugo A; Korosoglou, Grigorios

    2015-03-01

    To investigate if the extent of aortic valve calcification is associated with postprocedural prosthesis eccentricity and paravalvular regurgitation (PAR) in patients undergoing transcatheter aortic valve implantation (TAVI). Cardiac computed tomography angiography (CCTA) was performed before and 3 months after TAVI in 46 patients who received the self-expanding CoreValve and in 22 patients who underwent balloon-expandable Edwards Sapien XT implantation. Aortic annulus calcification was measured with CCTA prior to TAVI and prosthesis eccentricity was assessed with post-TAVI CCTA. Standard echocardiography was also performed in all patients at 3-month follow-up exam. Annulus eccentricity was reduced during TAVI using both implantation systems (from 0.23 ± 0.06 to 0.18 ± 0.07 using CoreValve and from 0.20 ± 0.07 to 0.05 ± 0.03 using Edwards Sapien XT; P<.001 for both). With Edwards Sapien XT, eccentricity reduction at the level of the aortic annulus was significantly higher compared with CoreValve (P<.001). Annulus eccentricity after CoreValve use was significantly related to absolute valve calcification and to valve calcification indexed to body surface area (BSA) (r = 0.48 and 0.50, respectively; P<.001 for both). Furthermore, a significant association was observed between aortic valve calcification and PAR (P<.01 by ANOVA) in patients who received CoreValve. Using ROC analysis, a cut-off value over 913 mm² aortic valve calcification predicted the occurrence of moderate or severe PAR with a sensitivity of 92% and a specificity of 63% (area under the curve = 0.75). Furthermore, multivariable analysis showed that aortic valve calcification was a robust predictor of postprocedural eccentricity and PAR, independent of the aortic annulus size and native valve eccentricity and of CoreValve prosthesis size (adjusted r = 0.46 and 0.50, respectively; P<.01 for both). Such associations were not present with the Edwards Sapien XT system. The extent of native aortic

  8. Tidal Disruption Events in Pan-STARRS1

    NASA Astrophysics Data System (ADS)

    Gezari, Suvi

    2018-01-01

    The Pan-STARRS1 (PS1) Medium Deep Survey made an important contribution to the study of tidal disruption events (TDEs) by discovering TDEs on the rise to peak and enabling prompt spectroscopic follow-up observations. The two PS1 TDEs, PS1-10jh and PS1-11af, were the first TDEs to have detailed light curves and transient broad line features in their spectra, both of which could be used to constrain the physical parameters of the events. I will describe how cotemporal NUV observations from the GALEX Time Domain Survey were critical in the identification of these relatively rare events as bonifide TDEs among the PS1 transient alert stream. I will also show how we can use the PS1+GALEX data set as a training set to prepare for culling TDEs from the deluge of transients to be produced by the next generation of optical time domain surveys, in order that they may be used as effective probes of supermassive black hole demographics and accretion physics.

  9. Diffuse-flow conceptualization and simulation of the Edwards aquifer, San Antonio region, Texas

    USGS Publications Warehouse

    Lindgren, R.J.

    2006-01-01

    A numerical ground-water-flow model (hereinafter, the conduit-flow Edwards aquifer model) of the karstic Edwards aquifer in south-central Texas was developed for a previous study on the basis of a conceptualization emphasizing conduit development and conduit flow, and included simulating conduits as one-cell-wide, continuously connected features. Uncertainties regarding the degree to which conduits pervade the Edwards aquifer and influence ground-water flow, as well as other uncertainties inherent in simulating conduits, raised the question of whether a model based on the conduit-flow conceptualization was the optimum model for the Edwards aquifer. Accordingly, a model with an alternative hydraulic conductivity distribution without conduits was developed in a study conducted during 2004-05 by the U.S. Geological Survey, in cooperation with the San Antonio Water System. The hydraulic conductivity distribution for the modified Edwards aquifer model (hereinafter, the diffuse-flow Edwards aquifer model), based primarily on a conceptualization in which flow in the aquifer predominantly is through a network of numerous small fractures and openings, includes 38 zones, with hydraulic conductivities ranging from 3 to 50,000 feet per day. Revision of model input data for the diffuse-flow Edwards aquifer model was limited to changes in the simulated hydraulic conductivity distribution. The root-mean-square error for 144 target wells for the calibrated steady-state simulation for the diffuse-flow Edwards aquifer model is 20.9 feet. This error represents about 3 percent of the total head difference across the model area. The simulated springflows for Comal and San Marcos Springs for the calibrated steady-state simulation were within 2.4 and 15 percent of the median springflows for the two springs, respectively. The transient calibration period for the diffuse-flow Edwards aquifer model was 1947-2000, with 648 monthly stress periods, the same as for the conduit-flow Edwards

  10. Telescoping magnetic ball bar test gage

    DOEpatents

    Bryan, James B.

    1984-01-01

    A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengageable servo drives which cannot be clutched out. Two gage balls (10, 12) are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit (14) and a rigid member (16, 18, 20, 22, 24). One gage ball (10) is secured by a magnetic socket knuckle assembly (34) which fixes its center with respect to the machine being tested. The other gage ball (12) is secured by another magnetic socket knuckle assembly (38) which is engaged or held by the machine in such manner that the center of that ball (12) is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball (10). As the moving ball (12) executes its trajectory, changes in the radial distance between the centers of the two balls (10, 12) caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly (50, 52, 54, 56, 58, 60) actuated by the parallel reed flexure unit (14). Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball (10) locations, thereby determining the accuracy of the machine.

  11. Process engineering with planetary ball mills.

    PubMed

    Burmeister, Christine Friederike; Kwade, Arno

    2013-09-21

    Planetary ball mills are well known and used for particle size reduction on laboratory and pilot scales for decades while during the last few years the application of planetary ball mills has extended to mechanochemical approaches. Processes inside planetary ball mills are complex and strongly depend on the processed material and synthesis and, thus, the optimum milling conditions have to be assessed for each individual system. The present review focuses on the insight into several parameters like properties of grinding balls, the filling ratio or revolution speed. It gives examples of the aspects of grinding and illustrates some general guidelines to follow for modelling processes in planetary ball mills in terms of refinement, synthesis' yield and contamination from wear. The amount of energy transferred from the milling tools to the powder is significant and hardly measurable for processes in planetary ball mills. Thus numerical simulations based on a discrete-element-method are used to describe the energy transfer to give an adequate description of the process by correlation with experiments. The simulations illustrate the effect of the geometry of planetary ball mills on the energy entry. In addition the imaging of motion patterns inside a planetary ball mill from simulations and video recordings is shown.

  12. Cricket Ball Aerodynamics: Myth Versus Science

    NASA Technical Reports Server (NTRS)

    Mehta, Rabindra D.; Koga, Demmis J. (Technical Monitor)

    2000-01-01

    Aerodynamics plays a prominent role in the flight of a cricket ball released by a bowler. The main interest is in the fact that the ball can follow a curved flight path that is not always under the control of the bowler. ne basic aerodynamic principles responsible for the nonlinear flight or "swing" of a cricket ball were identified several years ago and many papers have been published on the subject. In the last 20 years or so, several experimental investigations have been conducted on cricket ball swing, which revealed the amount of attainable swing, and the parameters that affect it. A general overview of these findings is presented with emphasis on the concept of late swing and the effects of meteorological conditions on swing. In addition, the relatively new concept of "reverse" swing, how it can be achieved in practice and the role in it of ball "tampering", are discussed in detail. A discussion of the "white" cricket ball used in last year's World Cup, which supposedly possesses different swing properties compared to a conventional red ball, is also presented.

  13. Using Geophysics to Define Hydrostratigraphic Units in the Edwards and Trinity Aquifers, Texas

    NASA Astrophysics Data System (ADS)

    Smith, B. D.; Blome, C. D.; Clark, A. K.; Kress, W.; Smith, D. V.

    2007-05-01

    Airborne and ground geophysical surveys conducted in Uvalde, Medina, and northern Bexar counties, Texas, can be used to define and characterize hydrostratigraphic units of the Edwards and Trinity aquifers. Airborne magnetic surveys have defined numerous Cretaceous intrusive stocks and laccoliths, mainly in Uvalde County, that influence local hydrology and perhaps regional ground-water flow paths. Depositional environments in the aquifers can be classified as shallow water platforms (San Marcos Platform, Edwards Group), shoal and reef facies (Devils River Trend, Devils River Formation), and deeper water basins (Maverick Basin, West Nueces, McKnight, and Salmon Peak Formations). Detailed airborne and ground electromagnetic surveys have been conducted over the Edwards aquifer catchment zone (exposed Trinity aquifer rocks), recharge zone (exposed Edwards aquifer rocks), and artesian zone (confined Edwards) in the Seco Creek area (northeast Uvalde and Medina Counties; Devils River Trend). These geophysical survey data have been used to divide the Edwards exposed within the Balcones fault zone into upper and lower hydrostratigraphic units. Although both units are high electrical resistivity, the upper unit has slightly lower resistivity than the lower unit. The Georgetown Formation, at the top of the Edwards Group has a moderate resistivity. The formations that comprise the upper confining units to the Edwards aquifer rocks have varying resistivities. The Eagleford and Del Rio Groups (mainly clays) have very low resistivities and are excellent electrical marker beds in the Seco Creek area. The Buda Limestone is characterized by high resistivities. Moderate resistivities characterize the Austin Group rocks (mainly chalk). The older Trinity aquifer, underlying the Edwards aquifer rocks, is characterized by less limestone (electrically resistive or low conductivity units) and greater quantities of mudstones (electrically conductive or low resistivity units). In the western

  14. Check valve

    DOEpatents

    Upton, Hubert Allen; Garcia, Pablo

    1999-08-24

    A check valve for use in a GDCS of a nuclear reactor and having a motor driven disk including a rotatable armature for rotating the check valve disk over its entire range of motion is described. In one embodiment, the check valve includes a valve body having a coolant flow channel extending therethrough. The coolant flow channel includes an inlet end and an outlet end. A valve body seat is located on an inner surface of the valve body. The check valve further includes a disk assembly, sometimes referred to as the motor driven disc, having a counterweight and a disk shaped valve. The disk valve includes a disk base having a seat for seating with the valve body seat. The disk assembly further includes a first hinge pin member which extends at least partially through the disk assembly and is engaged to the disk. The disk valve is rotatable relative to the first hinge pin member. The check valve also includes a motor having a stator frame with a stator bore therein. An armature is rotatably positioned within the stator bore and the armature is coupled to the disk valve to cause the disk valve to rotate about its full range of motion.

  15. Check valve

    DOEpatents

    Upton, H.A.; Garcia, P.

    1999-08-24

    A check valve for use in a GDCS of a nuclear reactor and having a motor driven disk including a rotatable armature for rotating the check valve disk over its entire range of motion is described. In one embodiment, the check valve includes a valve body having a coolant flow channel extending therethrough. The coolant flow channel includes an inlet end and an outlet end. A valve body seat is located on an inner surface of the valve body. The check valve further includes a disk assembly, sometimes referred to as the motor driven disc, having a counterweight and a disk shaped valve. The disk valve includes a disk base having a seat for seating with the valve body seat. The disk assembly further includes a first hinge pin member which extends at least partially through the disk assembly and is engaged to the disk. The disk valve is rotatable relative to the first hinge pin member. The check valve also includes a motor having a stator frame with a stator bore therein. An armature is rotatably positioned within the stator bore and the armature is coupled to the disk valve to cause the disk valve to rotate about its full range of motion. 5 figs.

  16. 2012 Problem 15: Frustrating Golf Ball

    NASA Astrophysics Data System (ADS)

    Huang, Shan; Zhu, Zheyuan; Gao, Wenli; Wang, Sihui

    2015-10-01

    This paper studies the condition for a golf ball to escape from a hole. The two determining factors are the ball's initial velocity v0 and its deviation from the center of the hole d. There is a critical escaping velocity vc for every deviation d. The ball's motion is analyzed by calculating the change of velocity whenever the ball collides with the hole. The critical conditions predicted by our theory are verified through experiment.

  17. Geologic framework of the Edwards Aquifer and upper confining unit, and hydrogeologic characteristics of the Edwards Aquifer, south-central Uvalde County, Texas

    USGS Publications Warehouse

    Clark, Allan K.; Small, Ted A.

    1997-01-01

    The stratigraphic units of the Edwards aquifer in south-central Uvalde County generally are porous and permeable. The stratigraphic units that compose the Edwards aquifer in south-central Uvalde County are the Devils River Formation in the Devils River trend; and the West Nueces, McKnight, and Salmon Peak Formations in the Maverick Basin. The Balcones fault zone is the principal structural feature in Uvalde County; however, the displacement along the fault zone is less in Uvalde County than in adjacent Medina and Bexar Counties to the east. The Uvalde Salient is a structural high in south-central Uvalde County, and consists of several closely connected crustal uplifts that bring Edwards aquifer strata to the surface generally forming prominent hills. The crustal uplifts forming this structural high are the remnants of intrusive and extrusive magnatic activity. Six primary faults—Cooks, Black Mountain, Blue Mountain, Uvalde, Agape, and Connor—cross the length of the study area from the southwest to the northeast juxtaposing the Lower Cretaceous Salmon Peak Formation at the surface in the northwestern part of the study area against Upper Cretaceous formations in the central part of the study area. In the study area, the porosity of the rocks in the Edwards aquifer is related to depositional or diagenetic elements along specific stratigraphic horizons (fabric selective) and to dissolution and structural elements that can occur in any lithostratigraphic horizon (not fabric selective). Permeability depends on the physical properties of the rock such as size, shape, distribution of pores, and fissuring and dissolution. The middle 185 feet of the lower part of the Devils River Formation, the upper part of the Devils River Formation, and the upper unit of the Salmon Peak Formation probably are the most porous and permeable stratigraphic zones of the Edwards aquifer in south-central Uvalde County.

  18. Great (Flame) Balls of Fire! Structure of Flame Balls at Low Lewis-number-2 (SOFBALL-2)

    NASA Technical Reports Server (NTRS)

    Ronney, Paul; Weiland, Karen J.; Over, Ann (Technical Monitor)

    2002-01-01

    Everyone knows that an automobile engine wastes fuel and energy when it runs with a fuel-rich mixture. 'Lean' burning, mixing in more air and less fuel, is better for the environment. But lean mixtures also lead to engine misfiring and rough operation. No one knows the ultimate limits for lean operation, for 'weak' combustion that is friendly to the environment while still moving us around. This is where the accidental verification of a decades-old prediction may have strong implications for designing and running low-emissions engines in the 21st century. In 1944, Soviet physicist Yakov Zeldovich predicted that stationary, spherical flames are possible under limited conditions in lean fuel-air mixtures. Dr. Paul Ronney of the University of Southern California accidentally discovered such 'flame balls' in experiments with lean hydrogen-air mixtures in 1984 during drop-tower experiments that provided just 2.2 seconds of near weightlessness. Experiments aboard NASA's low-g aircraft confirmed the results, but a thorough investigation was hampered by the aircraft's bumpy ride. And stable flame balls can only exist in microgravity. The potential for investigating combustion at the limits of flammability, and the implications for spacecraft fire safety, led to the Structure of Flame Balls at Low Lewis-number (SOFBALL) experiment flown twice aboard the Space Shuttle on the Microgravity Sciences Laboratory-1 (MSL-1) in 1997. Success there led to the planned reflight on STS-107. Flame balls are the weakest fires yet produced in space or on Earth. Typically each flame ball produced only 1 watt of thermal power. By comparison, a birthday candle produces 50 watts. The Lewis-number measures the rate of diffusion of fuel into the flame ball relative to the rate of diffusion of heat away from the flame ball. Lewis-number mixtures conduct heat poorly. Hydrogen and methane are the only fuels that provide low enough Lewis-numbers to produce stable flame balls, and even then only for

  19. Discovering Cepheid and RR Lyrae Stars: Pan-STARRS Science Archive @ STScI and Robotically Controlled Telescopes

    NASA Astrophysics Data System (ADS)

    Johnson, Elizabeth; Strolger, Louis-Gregory; Engle, Scott G.; Anderson, Richard I.; Rest, Armin; Calamida, Annalisa; Dosovitz Fox, Ori; Laney, David

    2017-01-01

    Cepheid and RR Lyrae stars are an integral part of the cosmic distance ladder and are also useful for studying galactic structure and stellar ages. This project aims to greatly expand the number of known periodic variables in our galaxy by identifying candidates in the PanSTARRS-1 3pi catalog, and carrying out systematically targeted characterization with robotically controlled telescopes. Candidate targets are selected from available detection tables based on color and variability indices and are then fully vetted using robotic telescopes: the RCT 1.3 meter (Kitt Peak National Observatory) and RATIR 1.5 meter (Mexico). Here we present work to develop a full, semi-automated prescription for candidate selection, targeted follow-up photometry, cataloging, and classification, which allows the review of approximately 25 variable candidates every two weeks. We make comparisons of our sample selection and purity from a similar study based on Pan-STARRS data (Hernitschek et al. 2016), as well as candidates identified in Gaia DR1. The goal, through continued observation and analysis, is to identify at least 10,000 new variables, hundreds of which will be new Cepheid and RR Lyrae stars.

  20. Corrosion-Resistant Ball Bearings

    NASA Technical Reports Server (NTRS)

    Zdankiewicz, E. M.; Linaburg, E. L.; Lytle, L. J.

    1990-01-01

    Self-lubricating bearing system withstands highly corrosive environment of wastewater-recycling unit. New bearings contain cobalt-based-alloy balls and races, graphite/polyimide polymer ball cages, and single integral polytetrafluoroethylene seals on wet sides. Materials and design prevent corrosion by acids and provide lubrication.

  1. Device Rotates Bearing Balls For Inspection

    NASA Technical Reports Server (NTRS)

    Burley, R. K.

    1988-01-01

    Entire surface of ball inspected automatically and quickly. Device holds and rotates bearing ball for inspection by optical or mechanical surface-quality probe, eddy-current probe for detection of surface or subsurface defects, or circumference-measuring tool. Ensures entire surface of ball moves past inspection head quickly. New device saves time and increases reliability of inspections of spherical surfaces. Simple to operate and provides quick and easy access for loading and unloading of balls during inspection.

  2. Physics in a Glitter Ball

    ERIC Educational Resources Information Center

    Trikosko, Walter

    2011-01-01

    Maui Toys' Water Bouncer (Fig. 1) is a water-filled ball containing glitter. Buy one and put it on your desk and students can't keep their hands off of it. Pitch the ball in the air giving it a quick spin. When you catch it you will see a sparkling vortex. Twist the ball around different ways and the angular momentum of the fluid keeps the axis of…

  3. Playing Ball in a Space Station

    ERIC Educational Resources Information Center

    Simoson, Andrew J.

    2006-01-01

    How does artificial gravity affect the path of a thrown ball? This paper contrasts ball trajectories on the Little Prince's asteroid planet B-612 and Arthur C. Clarke's rotating-drum spacecraft of 2001, and demonstrates curve balls with multiple loops in the latter environment.

  4. PEPC LRU: Ball Support Assembly

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alger, T

    1999-05-14

    The PEPC LRU upper ball support assembly consists of a ball and a pneumatic air cylinder/conical seat latching mechanism to be attached to the optics support frame,and a ball attached to the PEPC LRU. Both components are designed to allow manual positioning in three axes. Upon insertion of the PEPC LRU into the structure, the upper pneumatic cylinder is actuated to latch the two assemblies together through the conical seat device to grab the lower ball to support the LRU weight. To be conservative, the design load for the assembly is 1500 pounds (the prototype PEPC LRU weight was measuredmore » to be near 1380 pounds).« less

  5. Introduction to ball bearings

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1981-01-01

    The purpose of a ball bearing is to provide a relative positioning and rotational freedom while transmitting a load between two structures, usually a shaft and a housing. For high rotational speeds (e.g., in gyroscope ball bearings) the purpose can be expanded to include rotational freedom with practically no wear in the bearing. This condition can be achieved by separating the bearing parts with a coherent film of fluid known as an elastohydrodynamic film. This film can be maintained not only when the bearing carries the load on a shaft, but also when the bearing is preloaded to position the shaft to within micro- or nano-inch accuracy and stability. Background information on ball bearings is provided, different types of ball bearings and their geometry and kinematics are defined, bearing materials, manufacturing processes, and separators are discussed. It is assumed, for the purposes of analysis, that the bearing carries no load.

  6. Laboratory-produced ball lightning

    NASA Astrophysics Data System (ADS)

    Golka, Robert K., Jr.

    1994-05-01

    For 25 years I have actively been searching for the true nature of ball lightning and attempting to reproduce it at will in the laboratory. As one might expect, many unidentified lights in the atmosphere have been called ball lightning, including Texas Maffa lights (automobile headlights), flying saucers (UFOs), swamp gas in Ann Arbor, Michigan, etc. For 15 years I thought ball lightning was strictly a high-voltage phenomenon. It was not until 1984 when I was short-circuiting the electrical output of a diesel electric railroad locomotive that I realized that the phenomenon was related more to a high current. Although I am hoping for some other types of ball lightning to emerge such as strictly electrostatic-electromagnetic manifestations, I have been unlucky in finding laboratory provable evidence. Cavity-formed plasmodes can be made by putting a 2-inch burning candle in a home kitchen microwave oven. The plasmodes float around for as long as the microwave energy is present.

  7. Percutaneous pulmonary valve implantation for free pulmonary regurgitation following conduit-free surgery of the right ventricular outflow tract.

    PubMed

    Cools, Bjorn; Brown, Stephen C; Heying, Ruth; Jansen, Katrijn; Boshoff, Derize E; Budts, Werner; Gewillig, Marc

    2015-01-01

    Pulmonary regurgitation (PR) following surgery of the right ventricular outflow tract (RVOT) is not innocent and leads to significant right heart dysfunction over time. Recent studies have demonstrated that percutaneous valves can be implanted in conduit free outflow tracts with good outcomes. To evaluate in patients with severe PR--anticipated to require future pulmonary valve replacement--the feasibility and safety of pre-stenting dilated non-stenotic patched conduit-free right ventricular outflow tracts before excessive dilation occurs, followed by percutaneous pulmonary valve implantation (PPVI). Twenty seven patients were evaluated, but only 23 were deemed suitable based on the presence of an adequate retention zone ≤ 24 mm defined by semi-compliant balloon interrogation of the RVOT. A 2 step procedure was performed: first the landing zone was prepared by deploying a bare stent, followed 2 months later by valve implantation. RVOT pre-stenting with an open cell bare metal stent (Andrastent XXL range) was performed at a median age of 13.0 years (range: 6.0-44.9) with a median weight of 44.3 kg (range: 20.0-88.0). Ninety six percent (22/23) of patients proceeded to PPVI a median of 2.4 months (range: 1.4-3.4) after initial pre-stent placement. Twenty one Melody valves and one 26 mm Edwards SAPIEN™ valve were implanted. Complications consisted of embolization of prestent (n = 1), scrunching (n = 4) and mild stent dislocation (n = 2). During follow-up, no stent fractures were observed and right ventricular dimensions decreased significantly. Post-surgical conduit-free non-stenotic RVOT with free pulmonary regurgitation can be treated percutaneously with a valved stent if anatomical (predominantly size) criteria are met. In experienced hands, the technique is feasible with low morbidity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Flare angles measured with ball gage

    NASA Technical Reports Server (NTRS)

    Cleghorn, D.; Wall, W. A.

    1968-01-01

    Precision tungsten carbide balls measure the internal angle of flared joints. Measurements from small and large balls in the flare throat to an external reference point are made. The difference in distances and diameters determine the average slope of the flare between the points of ball contact.

  9. Ball mounting fixture for a roundness gage

    DOEpatents

    Gauler, Allen L.; Pasieka, Donald F.

    1983-01-01

    A ball mounting fixture for a roundness gage is disclosed. The fixture includes a pair of chuck assemblies oriented substantially transversely with respect to one another and mounted on a common base. Each chuck assembly preferably includes a rotary stage and a wobble plate affixed thereto. A ball chuck affixed to each wobble plate is operable to selectively support a ball to be measured for roundness, with the wobble plate permitting the ball chuck to be tilted to center the ball on the axis of rotation of the rotary stage. In a preferred embodiment, each chuck assembly includes a vacuum chuck operable to selectively support the ball to be measured for roundness. The mounting fixture enables a series of roundness measurements to be taken with a conventional rotating gagehead roundness instrument, which measurements can be utilized to determine the sphericity of the ball.

  10. Edward Wheeler Hones Jr. (1922-2012)

    NASA Astrophysics Data System (ADS)

    Baker, Daniel N.; McPherron, Robert L.; Birn, Joachim

    2013-02-01

    Space physicist Edward Wheeler Hones Jr. died on 17 September 2012 at his home in Los Alamos, N. M. He was 90 years old. The cause of death was a heart attack that came following a brief hospitalization.

  11. Polyurethane retainers for ball bearings

    NASA Technical Reports Server (NTRS)

    Christy, R. I.

    1973-01-01

    Evaluation of a new ball bearing retainer material is reported. A special composite polyurethane foam ball retainer has been developed that has virtually zero wear, is chemically inert to hydrocarbon lubricants, and stores up to 60 times as much lubricant per unit volume as the most commonly used retainer material, cotton phenolic. This new retainer concept shows promise of years of ball bearing operation without reoiling, based on life testing in high vacuum.

  12. Borner Ball Neutron Detector

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Bonner Ball Neutron Detector measures neutron radiation. Neutrons are uncharged atomic particles that have the ability to penetrate living tissues, harming human beings in space. The Bonner Ball Neutron Detector is one of three radiation experiments during Expedition Two. The others are the Phantom Torso and Dosimetric Mapping.

  13. Modeling of the Edwards pipe experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tiselj, I.; Petelin, S.

    1995-12-31

    The Edwards pipe experiment is used as one of the basic benchmarks for the two-phase flow codes due to its simple geometry and the wide range of phenomena that it covers. Edwards and O`Brien filled 4-m-long pipe with liquid water at 7 MPa and 502 K and ruptured one end of the tube. They measured pressure and void fraction during the blowdown. Important phenomena observed were pressure rarefaction wave, flashing onset, critical two-phase flow, and void fraction wave. Experimental data were used to analyze the capabilities of the RELAP5/MOD3.1 six-equation two-phase flow model and to examine two different numerical schemes:more » one from the RELAP5/MOD3.1 code and one from our own code, which was based on characteristic upwind discretization.« less

  14. Respiratory disease in ball pythons (Python regius) experimentally infected with ball python nidovirus.

    PubMed

    Hoon-Hanks, Laura L; Layton, Marylee L; Ossiboff, Robert J; Parker, John S L; Dubovi, Edward J; Stenglein, Mark D

    2018-04-01

    Circumstantial evidence has linked a new group of nidoviruses with respiratory disease in pythons, lizards, and cattle. We conducted experimental infections in ball pythons (Python regius) to test the hypothesis that ball python nidovirus (BPNV) infection results in respiratory disease. Three ball pythons were inoculated orally and intratracheally with cell culture isolated BPNV and two were sham inoculated. Antemortem choanal, oroesophageal, and cloacal swabs and postmortem tissues of infected snakes were positive for viral RNA, protein, and infectious virus by qRT-PCR, immunohistochemistry, western blot and virus isolation. Clinical signs included oral mucosal reddening, abundant mucus secretions, open-mouthed breathing, and anorexia. Histologic lesions included chronic-active mucinous rhinitis, stomatitis, tracheitis, esophagitis and proliferative interstitial pneumonia. Control snakes remained negative and free of clinical signs throughout the experiment. Our findings establish a causal relationship between nidovirus infection and respiratory disease in ball pythons and shed light on disease progression and transmission. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Fast-Acting Valve

    NASA Technical Reports Server (NTRS)

    Wojciechowski, Bogdan V. (Inventor); Pegg, Robert J. (Inventor)

    2003-01-01

    A fast-acting valve includes an annular valve seat that defines an annular valve orifice between the edges of the annular valve seat, an annular valve plug sized to cover the valve orifice when the valve is closed, and a valve-plug holder for moving the annular valve plug on and off the annular valve seat. The use of an annular orifice reduces the characteristic distance between the edges of the valve seat. Rather than this distance being equal to the diameter of the orifice, as it is for a conventional circular orifice, the characteristic distance equals the distance between the inner and outer radii (for a circular annulus). The reduced characteristic distance greatly reduces the gap required between the annular valve plug and the annular valve seat for the valve to be fully open, thereby greatly reducing the required stroke and corresponding speed and acceleration of the annular valve plug. The use of a valve-plug holder that is under independent control to move the annular valve plug between its open and closed positions is important for achieving controllable fast operation of the valve.

  16. Ball mounting fixture for a roundness gage

    DOEpatents

    Gauler, A.L.; Pasieka, D.F.

    1983-11-15

    A ball mounting fixture for a roundness gage is disclosed. The fixture includes a pair of chuck assemblies oriented substantially transversely with respect to one another and mounted on a common base. Each chuck assembly preferably includes a rotary stage and a wobble plate affixed thereto. A ball chuck affixed to each wobble plate is operable to selectively support a ball to be measured for roundness, with the wobble plate permitting the ball chuck to be tilted to center the ball on the axis of rotation of the rotary stage. In a preferred embodiment, each chuck assembly includes a vacuum chuck operable to selectively support the ball to be measured for roundness. The mounting fixture enables a series of roundness measurements to be taken with a conventional rotating gagehead roundness instrument, which measurements can be utilized to determine the sphericity of the ball. 6 figs.

  17. Automatic ball bar for a coordinate measuring machine

    DOEpatents

    Jostlein, H.

    1997-07-15

    An automatic ball bar for a coordinate measuring machine determines the accuracy of a coordinate measuring machine having at least one servo drive. The apparatus comprises a first and second gauge ball connected by a telescoping rigid member. The rigid member includes a switch such that inward radial movement of the second gauge ball relative to the first gauge ball causes activation of the switch. The first gauge ball is secured in a first magnetic socket assembly in order to maintain the first gauge ball at a fixed location with respect to the coordinate measuring machine. A second magnetic socket assembly secures the second gauge ball to the arm or probe holder of the coordinate measuring machine. The second gauge ball is then directed by the coordinate measuring machine to move radially inward from a point just beyond the length of the ball bar until the switch is activated. Upon switch activation, the position of the coordinate measuring machine is determined and compared to known ball bar length such that the accuracy of the coordinate measuring machine can be determined. 5 figs.

  18. Automatic ball bar for a coordinate measuring machine

    DOEpatents

    Jostlein, Hans

    1997-01-01

    An automatic ball bar for a coordinate measuring machine determines the accuracy of a coordinate measuring machine having at least one servo drive. The apparatus comprises a first and second gauge ball connected by a telescoping rigid member. The rigid member includes a switch such that inward radial movement of the second gauge ball relative to the first gauge ball causes activation of the switch. The first gauge ball is secured in a first magnetic socket assembly in order to maintain the first gauge ball at a fixed location with respect to the coordinate measuring machine. A second magnetic socket assembly secures the second gauge ball to the arm or probe holder of the coordinate measuring machine. The second gauge ball is then directed by the coordinate measuring machine to move radially inward from a point just beyond the length of the ball bar until the switch is activated. Upon switch activation, the position of the coordinate measuring machine is determined and compared to known ball bar length such that the accuracy of the coordinate measuring machine can be determined.

  19. Clinical outcomes of stapled transanal rectal resection (STARR) for obstructed defecation syndrome (ODS): a single institution experience in South Korea.

    PubMed

    Song, Kee Ho; Lee, Du Seok; Shin, Jong Keun; Lee, So Jin; Lee, Jae Bum; Yook, Eui Gon; Lee, Doo Han; Kim, Do Sun

    2011-06-01

    The purpose of this study was to assess both the short- and long-term functional outcomes of stapled transanal rectal resection (STARR) in ODS patients. We performed a retrospective review of data that were collected from January 2005 to October 2008. Between January 2005 to June 2006, 58 patients who underwent STARR were enrolled in this study. Follow-up was scheduled for 3 months and 1 year after surgery with the Cleveland Clinic Florida (CCF) constipation score and satisfaction grade. To evaluate the long-term functional outcome, we interviewed the patients by telephone using questionnaires for the CCF score and satisfaction grade on October 2008. The median follow-up period was 34 months (range, 27-46 months). The mean age and sex ratio were 54 years (range, 19-85 years) and 8:50 (M/F). The mean CCF constipation scores were 17.6 before the surgery, 9.5 at 3 months, 9.6 at 12 months, and 10.3 at the time of the latest interview. The satisfaction grade, which was rated as excellent and good by 63.4% of the patients at the time of the latest interview, was worse than that at 3 months (37.8%). Among the cases of the excellent group (19 cases) at postoperative 3 months, 13 cases (68.4%) were classified as excellent or good at the time of the latest interview. The STARR is a safe and effective surgical procedure for restoring the anatomy and function in ODS patients. Strict selection of patients is needed in enhancing and maintaining the patients' satisfaction after the procedure.

  20. Tricuspid Valve Repair for the Poor Right Ventricle: Tricuspid Valve Repair in Patients with Mild-to-Moderate Tricuspid Regurgitation Undergoing Mitral Valve Repair Improves In-Hospital Outcome.

    PubMed

    Zientara, Alicja; Genoni, Michele; Graves, Kirk; Odavic, Dragan; Löblein, Helen; Häussler, Achim; Dzemali, Omer

    2017-12-01

    Background  Tricuspid regurgitation (TR) in patients undergoing surgery for mitral valve (MV) increases morbidity and mortality, especially in case of a poor right ventricle. Does repair of mild-to-moderate insufficiency of the tricuspid valve (TV) in patients undergoing MV surgery lead to a benefit in early postoperative outcome? Methods  A total of 22 patients with mild-to-moderate TR underwent MV repair and concomitant TV repair with Tri-Ad (Medtronic ATS Medical Inc., Minneapolis, Minnesota, United States) and Edwards Cosgrove (Edwards Lifesciences Irvine, California, United States) rings. The severity of TR was assessed echocardiographically by using color-Doppler flow images. The tricuspid annular plane systolic excursion (TAPSE) was under 1.7 cm. Additional procedures included coronary artery bypass ( n  = 9) and maze procedure ( n  = 15). The following parameters were compared: postoperative and peak dose of noradrenaline (NA), pre/postoperative systolic pulmonary pressure (sPAP), extubation time, operation time, cross-clamp time, cardiopulmonary bypass (CPB) time, pre/postoperative ejection fraction (EF), intensive care unit (ICU)-stay, hospital stay, cell saver blood transfusion, intra/postoperative blood transfusion, and postoperative TR. Results  The mean age was 67 ± 14.8 years, 45% were male. Mean EF was 47 ± 16.2%, postoperative 52 ± 12.4%. sPAP was 46 ± 20.1 mm Hg preoperatively, sPAP was 40.6 ± 9.4 mm Hg postoperatively, NA postoperatively was 12 ± 10 μg/min, NA peak was 18 ± 11 μg/min, operation time was 275 ± 92 minutes, CPB was 145 ± 49 minutes, ICU stay was 2.4 ± 2.4 days, hospital stay was 10.8 ± 3.5 days, cell saver blood transfusion was 736 ± 346 mL, intraoperative transfusions were 2.5 ± 1.6. Two patients needed postoperative transfusions. A total of 19 patients were extubated at the 1st postoperative day, 2 patients at the 2nd day, and 1 at the 4th

  1. STS-64 Landing at Edwards

    NASA Image and Video Library

    1994-09-20

    The Space Shuttle Discovery settles to the main runway at Edwards, California, at 2:13 p.m. (PDT) 20 September 1994, to conclude mission STS-64. The spacecraft, with a crew of six, was launched into a 57-degree high inclination orbit from the Kennedy Space Center, Florida, at 3:23 p.m. (PDT), 9 September 1994. The mission featured the study of clouds and the atmosphere with a laser beaming system called Lidar In-Space Technology Experiment (LITE), and the first untethered space walk in over ten years. A Spartan satellite was also deployed and later retrieved in the study of the sun's corona and the solar wind. The mission was scheduled to end Sunday, 18 September, but was extended one day to continue science work. Bad weather at the Kennedy Space Center on September 19, forced a one-day delay to September 20, with a weather divert that day to Edwards. Mission commander was Richard Richards, the pilot Blaine Hammond, while mission specialists were Jerry Linenger, Susan Helms, Carl Meade, and Mark Lee.

  2. The relationships between impact location and post-impact ball speed, bat torsion, and ball direction in cricket batting.

    PubMed

    Peploe, C; McErlain-Naylor, S A; Harland, A R; King, M A

    2018-06-01

    Three-dimensional kinematic data of bat and ball were recorded for 239 individual shots performed by twenty batsmen ranging from club to international standard. The impact location of the ball on the bat face was determined and assessed against the resultant instantaneous post-impact ball speed and measures of post-impact bat torsion and ball direction. Significant negative linear relationships were found between post-impact ball speed and the absolute distance of impact from the midline medio-laterally and sweetspot longitudinally. Significant cubic relationships were found between the distance of impact from the midline of the bat medio-laterally and both a measure of bat torsion and the post-impact ball direction. A "sweet region" on the bat face was identified whereby impacts within 2 cm of the sweetspot in the medio-lateral direction, and 4.5 cm in the longitudinal direction, caused reductions in ball speed of less than 6% from the optimal value, and deviations in ball direction of less than 10° from the intended target. This study provides a greater understanding of the margin for error afforded to batsmen, allowing researchers to assess shot success in more detail, and highlights the importance of players generating consistently central impact locations when hitting for optimal performance.

  3. Thin coatings for heavy industry: Advanced coatings for pipes and valves

    NASA Astrophysics Data System (ADS)

    Vernhes, Luc

    characteristics suitable for applications such as pipes and valves. From these general objectives, three specific objectives were derived: 1) to select and assess the best candidates for alternatives to hard chromium electroplating, which has been classified by the U.S. Environmental Protection Agency (EPA) as an environmentally unfriendly process; 2) to investigate recurrent failures occurring in the field with thermal sprayed HVOF Cr3C 2-NiCr coating applied to Inconel 718 PH when exposed to supercritical steam lines and thermal shocks in supercritical power plants (determining the root causes of coating failures and assessing potential coating alternatives to alleviate these issues); and 3) to develop new coating architectures, including complex microstructures and interfaces, and to better understand and optimize complex tribomechanical properties. The main results are presented in the form of articles in peer-reviewed journals. In the first article, a variety of chromium-free protective coatings were assessed as alternatives to hard chromium (HC) electroplating, such as nanostructured cobalt-phosphor (NCP) deposited by electroplating and tungsten/tungsten carbide (W/WC) applied by chemical vapor deposition. In order to compare performance across the coatings, a series of laboratory tests were performed, including hardness, microscratch, pin-on-disk, and electrochemical polarization measurements. Mechanical and fatigue resistance were also determined using prototype valves with coated ball under severe tribocorrosion conditions. It was found that W/WC coating exhibits superior wear and corrosion resistance due to high hardness and high pitting resistance, respectively, whereas NCP exhibits better wear resistance than HC with alumina ball as well as low corrosion potential, making it suitable for use as sacrificial protective coating. Both nanostructured coatings exhibited superior tribomechanical and functional characteristics compared to HC. The second article presents an

  4. Thickness dependence and the role of spin transfer torque in nonlinear giant magnetoresistance of permalloy dual spin valves

    NASA Astrophysics Data System (ADS)

    Banerjee, N.; Aziz, A.; Ali, M.; Robinson, J. W. A.; Hickey, B. J.; Blamire, M. G.

    2010-12-01

    The recent discovery of nonlinear current-dependent magnetoresistance in dual spin valve devices [A. Aziz, O. P. Wessely, M. Ali, D. M. Edwards, C. H. Marrows, B. J. Hickey, and M. G. Blamire, Phys. Rev. Lett. 103, 237203 (2009)10.1103/PhysRevLett.103.237203] opens up the possibility for distinct physics which extends the standard model of giant magnetoresistance. When the outer ferromagnetic layers of a dual spin valve are antiparallel, the resulting accumulation of spin in the middle ferromagnetic layer strongly modifies its bulk and interfacial spin asymmetry and resistance. Here, we report experimental evidence of the role of bulk spin accumulation in this nonlinear effect and show that interfacial spin accumulation alone cannot account for the observed dependence of the effect on the thickness of the middle ferromagnetic layer. It is also shown that spin torque acting on the middle ferromagnetic layer combined with the nonlinear effect might be useful in understanding the dynamical features associated with the nonlinear behavior.

  5. Eddy-Current Inspection of Ball Bearings

    NASA Technical Reports Server (NTRS)

    Bankston, B.

    1985-01-01

    Custom eddy-current probe locates surface anomalies. Low friction air cushion within cone allows ball to roll easily. Eddy current probe reliably detects surface and near-surface cracks, voids, and material anomalies in bearing balls or other spherical objects. Defects in ball surface detected by probe displayed on CRT and recorded on strip-chart recorder.

  6. Relation Between Hertz Stress-Life Exponent, Ball-Race Conformity, and Ball Bearing Life

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.; Poplawski, Joseph V.; Root, Lawrence E.

    2008-01-01

    ANSI/ABMA and ISO standards based on Lundberg-Palmgren bearing life theory are normalized for ball bearings having inner- and outerrace conformities of 52 percent (0.52) and made from pre-1940 bearing steel. The Lundberg-Palmgren theory incorporates an inverse 9th power relation between Hertz stress and fatigue life for ball bearings. The effect of race conformity on ball set life independent of race life is not incorporated into the Lundberg-Palmgren theory. In addition, post-1960 vacuum-processed bearing steel exhibits a 12th power relation between Hertz stress and life. The work reported extends the previous work of Zaretsky, Poplawski, and Root to calculate changes in bearing life--that includes the life of the ball set--caused by race conformity, Hertz stress-life exponent, ball bearing type and bearing series. The bearing fatigue life in actual application will usually be equal to or greater than that calculated using the ANSI/ABMA and ISO standards that incorporate the Lundberg-Palmgren theory. The relative fatigue life of an individual race is more sensitive to changes in race conformity for Hertz stress-life exponent n of 12 than where n = 9. However, when the effects are combined to predict actual bearing life for a specified set of conditions and bearing geometry, the predicted life of the bearing will be greater for a value of n = 12 than n = 9.

  7. Relation between Hertz Stress-Life Exponent, Ball-Race Conformity, and Ball Bearing Life

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.; Poplawski, Joseph V.; Root, Lawrence E.

    2006-01-01

    ANSI/ABMA and ISO standards based on Lundberg-Palmgren bearing life theory are normalized for ball bearings having inner- and outer-race conformities of 52 percent (0.52) and made from pre-1940 bearing steel. The Lundberg-Palmgren theory incorporates an inverse 9th power relation between Hertz stress and fatigue life for ball bearings. The effect of race conformity on ball set life independent of race life is not incorporated into the Lundberg-Palmgren theory. In addition, post-1960 vacuum-processed bearing steel exhibits a 12th power relation between Hertz stress and life. The work reported extends the previous work of Zaretsky, Poplawski, and Root to calculate changes in bearing life, that includes the life of the ball set, caused by race conformity, Hertz stress-life exponent, ball bearing type and bearing series. The bearing fatigue life in actual application will usually be equal to or greater than that calculated using the ANSI/ABMA and ISO standards that incorporate the Lundberg-Palmgren theory. The relative fatigue life of an individual race is more sensitive to changes in race conformity for Hertz stress-life exponent n of 12 than where n = 9. However, when the effects are combined to predict actual bearing life for a specified set of conditions and bearing geometry, the predicted life of the bearing will be greater for a value of n = 12 than n = 9.

  8. Shock-Absorbent Ball-Screw Mechanism

    NASA Technical Reports Server (NTRS)

    Hirr, Otto A., Jr.; Meneely, R. W.

    1986-01-01

    Actuator containing two ball screws in series employs Belleville springs to reduce impact loads, thereby increasing life expectancy. New application of springs increases reliability of equipment in which ball screws commonly used. Set of three springs within lower screw of ball-screw mechanism absorbs impacts that result when parts reach their upper and lower limits of movement. Mechanism designed with Belleville springs as shock-absorbing elements because springs have good energy-to-volume ratio and easily stacked to attain any stiffness and travel.

  9. Optimal prosthesis sizing in transcatheter aortic valve implantation by exclusive use of three-dimensional transoesophageal echocardiography.

    PubMed

    Kretzschmar, Daniel; Lauten, Alexander; Goebel, Bjoern; Doenst, Torsten; Poerner, Tudor C; Ferrari, Markus; Figulla, Hans R; Hamadanchi, Ali

    2016-03-01

    The assessment of aortic annular size is critical, and inappropriate sizing is thought to be a main reason of paravalvular aortic regurgitation. Multidetector computed tomograph is associated with the risk of contrast nephropathy. For optimal evaluation of the complex structure of the aortic annulus, three-dimensional (3D)-methods should be used. We therefore sought to determine the value of 3D-transoesophageal echocardiography (3D-TEE) for appropriate sizing. Hundred and one patients (mean age 81·4 years) with symptomatic aortic valve stenosis (AS) and high surgical risk profile (mean log. EuroScore 28·8%) being scheduled for transcatheter aortic valve implantation (TAVI) were included. 2D- and 3D-TEE were performed before the procedure to evaluate the aortic annulus diameter. Maximum, minimum and mean (max diameter + min diameter/2) annulus diameters were 24·7, 23·1 and 23. 9 mm in 3D-TEE and compared to 22·6 mm in 2D-TEE (P<0·001; 0·07; <0·001). The interobserver variability for 3D-TEE was low with a mean difference of 0·18 mm compared to 2D-TEE with 0·59 mm. The application of 3D-TEE caused a change of prosthesis size selection in 40% of patients compared to 2D-TEE. In this study, we implanted three different types of catheter-mounted valves (Edwards-SAPIEN(™) XT valve, CoreValve(™) and JenaValve(™) ). Final angiography confirmed valve competence (mild insufficiency) in 91%, and there was no aortic regurgitation greater than moderate in the follow-up echocardiographic evaluation. Assessment of aortic annulus dimensions for TAVI size selection can safely be performed with 3D-TEE only. Based on our results with significantly higher annulus diameter compared to 2D-TEE, we recommend 3D-TEE to reduce prosthesis undersizing. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  10. Dual load path ball screw with rod end swivel

    NASA Technical Reports Server (NTRS)

    Wngett, Paul (Inventor)

    2002-01-01

    A dual drive ball has a ball screw shaft coupled at one end to a gear train and coupled at the other end to a ball screw nut. The ball screw shaft and ball screw nut are connected through complementary helical grooves filled with ball bearing balls. The outer surface of the ball screw nut is plined and can be driven by a second gear train. An output tube is coupled at one end to the ball screw nut and at its opposite end has a connector portion with a groove on its inner surface. A rod end has a coupling member for coupling to a surface to be actuated and a shaft portion with a groobe on its outer surface. This shaft portion is received with in the outputtube portion and the corresponding grooves are coupled through the use of a plurality of ball bearing balls.

  11. The principal time balls of New Zealand

    NASA Astrophysics Data System (ADS)

    Kinns, Roger

    2017-04-01

    Accurate time signals in New Zealand were important for navigation in the Pacific. Time balls at Wellington and Lyttelton were noted in the 1880 Admiralty list of time signals, with later addition of Otago. The time ball service at Wellington started in March 1864 using the first official observatory in New Zealand, but there was no Wellington time ball service during a long period of waterfront redevelopment during the 1880s. The time ball service restarted in November 1888 at a different harbour location. The original mechanical apparatus was used with a new ball, but the system was destroyed by fire in March 1909 and was never replaced. Instead, a time light service was inaugurated in 1912. The service at Lyttelton, near Christchurch, began in December 1876 after construction of the signal station there. It used telegraph signals from Wellington to regulate the time ball. By the end of 1909, it was the only official time ball in New Zealand, providing a service that lasted until 1934. The Lyttelton time ball tower was an iconic landmark in New Zealand that had been carefully restored. Tragically, the tower collapsed in the 2011 earthquakes and aftershocks that devastated Christchurch. A daily time ball service at Port Chalmers, near Dunedin, started in June 1867, initially using local observatory facilities. The service appears to have been discontinued in October 1877, but was re-established in April 1882 as a weekly service, with control by telegraph from Wellington. The service had been withdrawn altogether by the end of 1909. Auckland never established a reliable time ball service, despite provision of a weekly service for mariners by a public-spirited citizen between August 1864 and June 1866. A time ball was finally installed on the Harbour Board building in 1901, but the signal was unreliable and it ceased in 1902. Complaints from ships' masters led to various proposals to re-establish a service. These concluded with erection of a time ball on the new

  12. The dynamics of hurricane balls

    NASA Astrophysics Data System (ADS)

    Andersen, W. L.; Werner, Steven

    2015-09-01

    We examine the theory of the hurricane balls toy. This toy consists of two steel balls, welded together that are sent spinning on a horizontal surface somewhat like a top. Unlike a top, at high frequency the symmetry axis approaches a limiting inclination that is not perpendicular to the surface. We calculate (and experimentally verify) the limiting inclinations for three toy geometries. We find that at high frequencies, hurricane balls provide an easily realized and testable example of the Poinsot theory of freely rotating symmetrical bodies.

  13. Bioprosthetic Valve Fracture During Valve-in-valve TAVR: Bench to Bedside

    PubMed Central

    Saxon, John T; Allen, Keith B; Cohen, David J

    2018-01-01

    Valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR) has been established as a safe and effective means of treating failed surgical bioprosthetic valves (BPVs) in patients at high risk for complications related to reoperation. Patients who undergo VIV TAVR are at risk of patient–prosthesis mismatch, as the transcatheter heart valve (THV) is implanted within the ring of the existing BPV, limiting full expansion and reducing the maximum achievable effective orifice area of the THV. Importantly, patient–prosthesis mismatch and high residual transvalvular gradients are associated with reduced survival following VIV TAVR. Bioprosthetic valve fracture (BVF) is as a novel technique to address this problem. During BPV, a non-compliant valvuloplasty balloon is positioned within the BPV frame, and a highpressure balloon inflation is performed to fracture the surgical sewing ring of the BPV. This allows for further expansion of the BPV as well as the implanted THV, thus increasing the maximum effective orifice area that can be achieved after VIV TAVR. This review focuses on the current evidence base for BVF to facilitate VIV TAVR, including initial bench testing, procedural technique, clinical experience and future directions. PMID:29593832

  14. Bioprosthetic Valve Fracture During Valve-in-valve TAVR: Bench to Bedside.

    PubMed

    Saxon, John T; Allen, Keith B; Cohen, David J; Chhatriwalla, Adnan K

    2018-01-01

    Valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR) has been established as a safe and effective means of treating failed surgical bioprosthetic valves (BPVs) in patients at high risk for complications related to reoperation. Patients who undergo VIV TAVR are at risk of patient-prosthesis mismatch, as the transcatheter heart valve (THV) is implanted within the ring of the existing BPV, limiting full expansion and reducing the maximum achievable effective orifice area of the THV. Importantly, patient-prosthesis mismatch and high residual transvalvular gradients are associated with reduced survival following VIV TAVR. Bioprosthetic valve fracture (BVF) is as a novel technique to address this problem. During BPV, a non-compliant valvuloplasty balloon is positioned within the BPV frame, and a highpressure balloon inflation is performed to fracture the surgical sewing ring of the BPV. This allows for further expansion of the BPV as well as the implanted THV, thus increasing the maximum effective orifice area that can be achieved after VIV TAVR. This review focuses on the current evidence base for BVF to facilitate VIV TAVR, including initial bench testing, procedural technique, clinical experience and future directions.

  15. Simulations of flow in the Edwards-Trinity aquifer system and contiguous hydraulically connected units, west-central Texas

    USGS Publications Warehouse

    Kuniansky, E.L.; Holligan, K.Q.

    1994-01-01

    The transmissivity values used in the simulations were within estimated ranges and generally are: 1,000 to 10,000 ft2/d (feet squared per day) for the Edwards-Trinity and Trinity aquifers; 100,000 to greater than 1 million ft2/d for the Edwards aquifer; and less than 500 to 10,000 ft2/d in contiguous hydraulically connected units. Simulated flow through the Edwards-Trinity aquifer system and contiguous hydraulically connected units is about 3 million acre-feet per year. Estimates of areally distributed recharge from the simulations range from 0.1 to 1 inch per year for the Edwards-Trinity aquifer and increase to 4 inches per year for the Trinity aquifer. Recharge to the Edwards aquifer occurs along streambeds that cross outcropped high-permeability rocks of the Edwards Group through joints and faults. Many of the streams are diverted completely underground during periods of no precipitation. The movement of a substantial quantity of water (about 400 cubic feet per second) from the Trinity and Edwards-Trinity aquifers into the Edwards aquifer was simulated. Results of the simulations indicate that anisotropy strongly influences flow in the Edwards aquifer. In the San Antonio and Austin areas, the Edwards aquifer is the most active part of the ground-water flow system with one-third of ground-water discharge occurring in 5 percent of the modeled area for both simulations.

  16. Water ball collision

    NASA Technical Reports Server (NTRS)

    Fujimoto, K.

    1986-01-01

    What happens if a stainless steel ball hits a water ball in the weightless space ot the Universe? In other words, it was the objective of our experiments in the Space to observe the surface tension of liquid by means of making a solid collide with a liquid. Place a small volume of water between 2 glass sheets to make a thin water membrane: the 2 glass sheets cannot be separated unless an enormous force is applied. It is obvious from this phenomenom that the surface tension of water is far greater than presumed. On Earth, however, it is impossible in most cases to observe only the surface tension of liquid, because gravity always acts on the surface tension. Water and stainless steel balls were chosen the liquid and solids for the experiments. Because water is the liquid most familiar to us, its properties are well known. And it is also of great interest to compare its properties on the Earth with those in the weightless space.

  17. Ball Screw Actuator Including a Stop with an Integral Guide

    NASA Technical Reports Server (NTRS)

    Wingett, Paul T. (Inventor); Perek, John (Inventor); Geck, Kellan (Inventor)

    2015-01-01

    An actuator includes a housing assembly, a ball nut, a ball screw, and a ball screw stop. The ball nut is rotationally mounted in the housing assembly, is adapted to receive an input torque, and is configured, upon receipt thereof, to rotate and supply a drive force. The ball screw is mounted within the housing assembly and extends through the ball nut. The ball screw has a first end and a second end, and is coupled to receive the drive force from the ball nut. The ball screw is configured, upon receipt of the drive force, to selectively translate between a stow position and a deploy position. The ball screw stop is mounted on the ball screw to translate therewith and is configured to at selectively engage the housing assembly while the ball screw is translating, and engage the ball nut when the ball screw is in the deploy position.

  18. Transcatheter or Surgical Aortic-Valve Replacement in Intermediate-Risk Patients.

    PubMed

    Leon, Martin B; Smith, Craig R; Mack, Michael J; Makkar, Raj R; Svensson, Lars G; Kodali, Susheel K; Thourani, Vinod H; Tuzcu, E Murat; Miller, D Craig; Herrmann, Howard C; Doshi, Darshan; Cohen, David J; Pichard, Augusto D; Kapadia, Samir; Dewey, Todd; Babaliaros, Vasilis; Szeto, Wilson Y; Williams, Mathew R; Kereiakes, Dean; Zajarias, Alan; Greason, Kevin L; Whisenant, Brian K; Hodson, Robert W; Moses, Jeffrey W; Trento, Alfredo; Brown, David L; Fearon, William F; Pibarot, Philippe; Hahn, Rebecca T; Jaber, Wael A; Anderson, William N; Alu, Maria C; Webb, John G

    2016-04-28

    Previous trials have shown that among high-risk patients with aortic stenosis, survival rates are similar with transcatheter aortic-valve replacement (TAVR) and surgical aortic-valve replacement. We evaluated the two procedures in a randomized trial involving intermediate-risk patients. We randomly assigned 2032 intermediate-risk patients with severe aortic stenosis, at 57 centers, to undergo either TAVR or surgical replacement. The primary end point was death from any cause or disabling stroke at 2 years. The primary hypothesis was that TAVR would not be inferior to surgical replacement. Before randomization, patients were entered into one of two cohorts on the basis of clinical and imaging findings; 76.3% of the patients were included in the transfemoral-access cohort and 23.7% in the transthoracic-access cohort. The rate of death from any cause or disabling stroke was similar in the TAVR group and the surgery group (P=0.001 for noninferiority). At 2 years, the Kaplan-Meier event rates were 19.3% in the TAVR group and 21.1% in the surgery group (hazard ratio in the TAVR group, 0.89; 95% confidence interval [CI], 0.73 to 1.09; P=0.25). In the transfemoral-access cohort, TAVR resulted in a lower rate of death or disabling stroke than surgery (hazard ratio, 0.79; 95% CI, 0.62 to 1.00; P=0.05), whereas in the transthoracic-access cohort, outcomes were similar in the two groups. TAVR resulted in larger aortic-valve areas than did surgery and also resulted in lower rates of acute kidney injury, severe bleeding, and new-onset atrial fibrillation; surgery resulted in fewer major vascular complications and less paravalvular aortic regurgitation. In intermediate-risk patients, TAVR was similar to surgical aortic-valve replacement with respect to the primary end point of death or disabling stroke. (Funded by Edwards Lifesciences; PARTNER 2 ClinicalTrials.gov number, NCT01314313.).

  19. Promoting ball skills in preschool-age girls.

    PubMed

    Veldman, Sanne L C; Palmer, Kara K; Okely, Anthony D; Robinson, Leah E

    2017-01-01

    Evidence supports that girls are less proficient than boys at performing ball skills. This study examined the immediate and long-term effects of a ball skill intervention on preschool-age girls' ball skill performance. Randomized controlled trial. Girls (M age =47.24±7.38 months) were randomly assigned to a high autonomy, mastery-based 9-week motor skill intervention (the Children's Health Activity Motor Program; CHAMP, 540min; n=38) or a control group (free-play; n=16). Ball skill proficiency was assessed at pretest, posttest, and retention test (after 9 weeks) using the object control subscale of the Test of Gross Motor Development - 2nd Edition. Treatment efficacy was examined using linear mixed models. Two models were fit: one for short-term changes (pretest to posttest) and one for long-term changes (pretest to retention). Linear mixed models revealed a significantly time*treatment interaction for both models. Post hoc analysis confirmed that girls in CHAMP experienced significant gains in ball skills from pretest to posttest (p<.001) and pretest to retention (p<.001). Moreover, girls in CHAMP were no different from the control group at pretest (p>.05) but had significantly higher ball skills scores at both posttest (p<.001) and retention (p<.001). This study demonstrates the positive effects of a ball skill intervention (i.e., CHAMP) on improving girls' ball skills both short- and long-term. Findings suggest that early childhood interventions that focus on the development of ball skills in young girls might be an avenue to improve girls' ball skill performance. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  20. A formula for comparison of selected sport ball compressibility.

    PubMed Central

    Dowell, L J; Krebs, G

    1991-01-01

    The purpose of this study was to develop a formula to determine and compare the compressibility of selected sport balls. Six balls (basketball, volleyball, soccer ball, baseball, handball, golf ball) were dropped ten times from each of four different heights onto a smooth solid surface overlaid with a white sheet of typing paper, overlaid with a sheet of carbon paper. The diameter of the area of contact of each ball imprinted onto the typing paper was measured in millimetres with calipers. From the data, the distance (d) that each ball compressed for each velocity (v) was calculated. It was found that a linear relationship existed between velocity at impact and the distance for each ball studied. The compressibility coefficient (c) for each ball was calculated and a formula was developed to determine the distance each ball would compress at a given velocity. When velocity is measured in metres per second and the distance a ball compresses is measured in millimetres, the formula to determine d for selected balls, in order of compressibility is: basketball d = 3.07v, volleyball d = 2.90v, soccer ball d = 2.80v, baseball d = 0.77v, handball d = 0.53v, and golf ball d = 0.17v. PMID:1913029

  1. Geologic framework and hydrogeologic characteristics of the Edwards Aquifer outcrop, Hays County, Texas

    USGS Publications Warehouse

    Hanson, John A.; Small, Ted A.

    1995-01-01

    All of the hydrogeologic subdivisions within the Edwards aquifer outcrop in Hays County have some porosity and permeability. The most porous and permeable appear to be hydrogeologic subdivision VI, the Kirschberg evaporite member of the Kainer Formation; hydrogeologic subdivision III, the leached and collapsed members, undivided; and hydrogeologic subdivision II, the cyclic and marine members, undivided, of the Person Formation. The two types of porosity in the Edwards aquifer outcrop are fabric selective, which is related to depositional or diagenetic elements and typically exists in specific stratigraphic horizons; and not fabric selective, which can exist in any lithostratigraphic horizon. Permeability, the capacity of porous rock to transmit water, depends on the physical properties of the rock such as size, shape, and distribution of pores, and fissuring and dissolution. Two faults, San Marcos Springs and Mustang Branch, completely, or almost completely, offset the Edwards aquifer by juxtaposing Edwards aquifer limestone against nearly impermeable upper confining units along parts of their traces across Hays County. These faults are thought to be barriers, or partial barriers, to groundwater flow where the beds are juxtaposed. In Hays County, the Edwards aquifer probably is most vulnerable to surface contamination in the rapidly urbanizing areas on the Edwards aquifer outcrop. Contamination can result from spills or leakage of hazardous materials; or runoff on the intensely faulted and fractured, karstic limestone outcrops characteristic of the recharge zone.

  2. Quality of water in the Trinity and Edwards aquifers, south-central Texas, 1996-98

    USGS Publications Warehouse

    Fahlquist, Lynne; Ardis, Ann F.

    2004-01-01

    During 1996–98, the U.S. Geological Survey studied surface- and ground-water quality in south-central Texas. The ground-water components included the upper and middle zones (undifferentiated) of the Trinity aquifer in the Hill Country and the unconfined part (recharge zone) and confined part (artesian zone) of the Edwards aquifer in the Balcones fault zone of the San Antonio region. The study was supplemented by information compiled from four ground-water-quality studies done during 1996–98.Trinity aquifer waters are more mineralized and contain larger dissolved solids, sulfate, and chloride concentrations compared to Edwards aquifer waters. Greater variability in water chemistry in the Trinity aquifer likely reflects the more variable lithology of the host rock. Trace elements were widely detected, mostly at small concentrations. Median total nitrogen was larger in the Edwards aquifer than in the Trinity aquifer. Ammonia nitrogen was detected more frequently and at larger concentrations in the Trinity aquifer than in the Edwards aquifer. Although some nitrate nitrogen concentrations in the Edwards aquifer exceeded a U.S. Geological Survey national background threshold concentration, no concentrations exceeded the U.S. Environmental Protection Agency public drinking-water standard.Synthetic organic compounds, such as pesticides and volatile organic compounds, were detected in the Edwards aquifer and less frequently in the Trinity aquifer, mostly at very small concentrations (less than 1 microgram per liter). These compounds were detected most frequently in urban unconfined Edwards aquifer samples. Atrazine and its breakdown product deethylatrazine were the most frequently detected pesticides, and trihalomethanes were the most frequently detected volatile organic compounds. Widespread detections of these compounds, although at small concentrations, indicate that anthropogenic activities affect ground-water quality.Radon gas was detected throughout the Trinity

  3. Ball bearing heat analysis program (BABHAP)

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The Ball Bearing Heat Analysis Program (BABHAP) is an attempt to assemble a series of equations, some of which are non-linear algebraic systems, in a logical order, which when solved, provide a complex analysis of load distribution among the balls, ball velocities, heat generation resulting from friction, applied load, and ball spinning, minimum lubricant film thickness, and many additional characteristics of ball bearing systems. Although initial design requirements for BABHAP were dictated by the core limitations of the PDP 11/45 computer, (approximately 8K of real words with limited number of instructions) the program dimensions can easily be expanded for large core computers such as the UNIVAC 1108. The PDP version of BABHAP is also operational on the UNIVAC system with the exception that the PDP uses 029 punch and the UNIVAC uses 026. A conversion program was written to allow transfer between machines.

  4. Assessing methods of enhancing older driver performance.

    DOT National Transportation Integrated Search

    2013-05-01

    Research has demonstrated improvements in neuropsychological measuresfollowing participation in : cognitive training programs in normal aging individuals (Ball, et al., 2002; Ball, Edwards, & Ross, 2007; : Willis, et al., 2006; Wolinsky, et al., 2006...

  5. Prince Edward Island's School Psychology Report

    ERIC Educational Resources Information Center

    Matters, Rhonda

    2016-01-01

    The Prince Edward Island (PEI) school system has been struggling with issues of recruitment and particularly retention for psychologists. Reasons include concerns about professional autonomy; having more limited roles, which are heavily assessment focused; reduced job satisfaction; and restrictions on additional private practice work. The waiting…

  6. PORTRAIT - ASTRONAUT WHITE, EDWARD H. - MSC

    NASA Image and Video Library

    1966-05-12

    S66-35219 (1966) --- Astronaut Edward H. White II (United States Air Force Lieutenant Colonel), Gemini 4 pilot. Editor's Note: Since this portrait was taken astronaut White lost his life on Jan. 27, 1967, in the Apollo 1/Saturn 204 fire at Cape Kennedy, KSC, Florida.

  7. Control Valve

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moore, Wayne R.

    A control valve includes a first conduit having a first inlet and a first outlet and defining a first passage; a second conduit having a second inlet and a second outlet and defining a second passage, the second conduit extending into the first passage such that the second inlet is located within the first passage; and a valve plate disposed pivotably within the first passage, the valve plate defining a valve plate surface. Pivoting of the valve plate within the first passage varies flow from the first inlet to the first outlet and the valve plate is pivotal between amore » first position and a second position such that in the first position the valve plate substantially prevents fluid communication between the first passage and the second passage and such that in the second position the valve plate permits fluid communication between the first passage and the second passage.« less

  8. Flight trajectory of a rotating golf ball with grooves

    NASA Astrophysics Data System (ADS)

    Baek, Moonheum; Kim, Jooha; Choi, Haecheon

    2014-11-01

    Dimples are known to reduce drag on a sphere by the amount of 50% as compared to a smooth surface. Despite the advantage of reducing drag, dimples deteriorate the putting accuracy owing to their sharp edges. To minimize this putting error but maintain the same flight distance, we have devised a grooved golf ball (called G ball hereafter) for several years. In this study, we modify the shape and pattern of grooves, and investigate the flow characteristics of the G ball by performing wind-tunnel experiments at the Reynolds numbers of 0 . 5 ×105 - 2 . 5 ×105 and the spin ratios (ratio of surface velocity to the free-stream velocity) of 0 - 0.6 that include the real golf-ball velocity and rotational speed. We measure the drag and lift forces on the rotating G ball and compare them with those of a smooth ball and two well-known dimpled balls. The lift-to-drag ratio of the G ball is much higher than that of a smooth ball and is in between those of the two dimpled balls. The trajectories of flying golf balls are computed. The flight distance of G ball is almost the same as that of one dimpled ball but slightly shorter than that of the other dimpled ball. The fluid-dynamic aspects of these differences will be discussed at the talk. Supported by 2011-0028032, 2014M3C1B1033980.

  9. Acting Administrator Lightfoot Visits Ball Aerospace

    NASA Image and Video Library

    2017-04-06

    Acting NASA Deputy Administrator Lesa Roe, second from left, and acting NASA Administrator Robert Lightfoot, second from left, are seen with Mike Gazarik, vice president of Engineering at Ball Aerospace, left and Shawn Conley, test operations manager at Ball Aerospace, left, in front of the large semi-anechoic chamber, Thursday, April 6, 2017 during a visit to Ball Aerospace in Boulder, Colo. Photo Credit: (NASA/Joel Kowsky)

  10. Ball-morph: definition, implementation, and comparative evaluation.

    PubMed

    Whited, Brian; Rossignac, Jaroslaw Jarek

    2011-06-01

    We define b-compatibility for planar curves and propose three ball morphing techniques between pairs of b-compatible curves. Ball-morphs use the automatic ball-map correspondence, proposed by Chazal et al., from which we derive different vertex trajectories (linear, circular, and parabolic). All three morphs are symmetric, meeting both curves with the same angle, which is a right angle for the circular and parabolic. We provide simple constructions for these ball-morphs and compare them to each other and other simple morphs (linear-interpolation, closest-projection, curvature-interpolation, Laplace-blending, and heat-propagation) using six cost measures (travel-distance, distortion, stretch, local acceleration, average squared mean curvature, and maximum squared mean curvature). The results depend heavily on the input curves. Nevertheless, we found that the linear ball-morph has consistently the shortest travel-distance and the circular ball-morph has the least amount of distortion.

  11. Rolling-element fatigue life of AMS 5900 balls

    NASA Technical Reports Server (NTRS)

    Parker, R. J.

    1983-01-01

    The rolling-element fatigue life of AMS 5900 12.7-mm (1/2-in.) dia was determined in five-ball fatigue testers. The 10% life with the warm headed AMS 5900 balls was equivalent to that of AMS 5749 and over eight times that of AISI M-50. The AMS balls fabricated by cold heading had small surface cracks which initiated fatigue spalls where these cracks were crossed by running tracks. The cold-headed AMS 5900 balls had a 10% fatigue life an order of magnitude less than that of the warm headed balls even when failures on the cold headed balls at visible surface cracks were omitted.

  12. Measurements of drag and lift on smooth balls in flight

    NASA Astrophysics Data System (ADS)

    Cross, Rod; Lindsey, Crawford

    2017-07-01

    Measurements are presented on the drag and lift coefficients for three relatively smooth balls launched in air and tracked with two cameras separated horizontally by 6.4 m. The ball spin was varied in order to investigate whether the Magnus force would increase or decrease when the ball spin was increased. For one ball, the Magnus force increased. For another ball, the Magnus force decreased almost to zero after reaching a maximum. For the third ball, the Magnus force was negative at low ball spins and positive at high ball spins. For one of the balls, the ball spin increased with time as it travelled through the air.

  13. Nuclear radiation actuated valve

    DOEpatents

    Christiansen, David W.; Schively, Dixon P.

    1985-01-01

    A nuclear radiation actuated valve for a nuclear reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

  14. Ball-joint grounding ring

    NASA Technical Reports Server (NTRS)

    Aperlo, P. J. A.; Buck, P. A.; Weldon, V. A.

    1981-01-01

    In ball and socket joint where electrical insulator such as polytetrafluoroethylene is used as line to minimize friction, good electrical contact across joint may be needed for lightning protection or to prevent static-charge build-up. Electrical contact is maintained by ring of spring-loaded fingers mounted in socket. It may be useful in industry for cranes, trailers, and other applications requiring ball and socket joint.

  15. SOFIA (+FORCAST) Infrared Spectrophotometry of Comet C/2012 K1 (PanStarrs)

    NASA Astrophysics Data System (ADS)

    Woodward, Charles E.; Kelley, Michael S.P.; Wooden, Diane H.; Harker, David E.; De Buizer, James M.; Gicquel, Adeline

    2014-11-01

    Observing and modeling the properties of small, primitive bodies in the solar system whose origins lie beyond the frost line (> 5 AU) provides critical insight into the formation of the first Solar System solids and establishes observation constraints for planetary system formation invoking migration - the ‘Grand Tack’ epoch followed by the ‘Nice Model’ events - that yielded terrestrial planets in the habitable zone. The characteristics of comet dust can provide evidence to validate the new, emerging picture of small body populations - including comet families - resulting from planetary migration in the early Solar System. Here we present preliminary results of infrared 8 to 27 micron spectrophotometric observations of comet C/2012 K1 (PanStarrs), a dynamically new (1/a0 < 50e-6) Oort Cloud comet, conducted with the NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) facility during a series of three flights over the period from 2014 June 06-11 UT. During this interval comet C/2012 K1 (PanStarrs) was at a heliocentric distance of ~1.64 AU and a geocentric distance of ~1.74 AU (pre-perihelion). As a "new" comet (first inner solar system passage), the coma grain population may be extremely pristine, unencumbered by a rime and insufficiently irradiated by the Sun to carbonize its surface organics. We will discuss the derived coma grain properties inferred from modeling of the spectral energy distribution derived from the SOFIA (+FORCAST) data and highlight our preliminary conclusions. Continued observations of comets, especially dynamically young Oort Cloud targets, in the 5-37 micron infrared spectral range accessible with SOFIA (+FORCAST) will provide key observational clues to ascertaining the origins of silicates within our protoplanetary disk, and will serve to place our early disk evolution within the context of other circumstellar disks observed today that may contain the seeds of rocky, terrestrial planets.

  16. Measuring the rebound resilience of a bouncing ball

    NASA Astrophysics Data System (ADS)

    Wadhwa, Ajay

    2012-09-01

    Some balls which are made of high-quality rubber (an elastomeric) material, such as tennis or squash balls, could be used for the determination of an important property of such materials called resilience. Since a bouncing ball involves a single impact we call this property 'rebound resilience' and express it as the ratio of the rebound height to the initial drop height of the ball. We determine the rebound resilience for three different types of ball by calculating the coefficient of restitution of the ball-surface combination from the experimentally measurable physical quantities, such as initial drop height and time interval between successive bounces. Using these we also determine the contact time of balls with the surface of impact. For measurements we have used audio, motion and surface-temperature sensors that were interfaced through a USB port with a computer.

  17. Carbon nanotube balls and their application in supercapacitors.

    PubMed

    Kang, Da-Young; Moon, Jun Hyuk

    2014-01-08

    We have provided a design of the macroscopic morphology of carbon nanotubes (CNTs) using emulsion droplet confinement. The evaporation of CNT-dispersed aqueous emulsion droplets in oil produces spherical CNT assemblies, i.e., CNT balls. In this emulsion-assisted method, compact packing of CNT was obtained by the presence of capillary pressure during droplet evaporation. The size of the CNT balls could be controlled by changing the concentration of the CNT dispersion solution; typically, CNT balls with an average size in the range of 8-12 μm were obtained with a Brunauer-Emmett-Teller (BET) specific area of 200 m(2)/g. Heat treatment of the CNT balls, which was required to remove residual solvent, and cement CNTs was followed, and their effect has been characterized; the heat treatment at high temperature desorbed surface oxygenated groups of CNTs and created defective carbon structures, but did not change pore structure. The dispersion of CNT balls was applied to form CNT ball-assembled film for a supercapacitor electrode. The specific capacitance of 80 F/g was obtained at 500 °C heat treatment, but the CNT balls prepared at a higher temperature actually decreased the capacitance, because of the removal of surface oxygenated groups, thereby decreasing the pseudo-capacitance. The capacitive properties of CNT ball-assembled electrodes were compared to CNT films; the CNT ball electrodes showed 40% higher specific electrochemical capacitance and higher rate performance, which is attributed to the compact packing of CNTs in the CNT ball and the hierarchical porous structures in the ball assemblies.

  18. Q-balls in flat potentials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Copeland, Edmund J.; Tsumagari, Mitsuo I.

    2009-07-15

    We study the classical and absolute stability of Q-balls in scalar field theories with flat potentials arising in both gravity-mediated and gauge-mediated models. We show that the associated Q-matter formed in gravity-mediated potentials can be stable against decay into their own free particles as long as the coupling constant of the nonrenormalizable term is small, and that all of the possible three-dimensional Q-ball configurations are classically stable against linear fluctuations. Three-dimensional gauge-mediated Q-balls can be absolutely stable in the thin-wall limit, but are completely unstable in the thick-wall limit.

  19. Hex ball torque test

    NASA Technical Reports Server (NTRS)

    Robinson, B. A.; Foster, C. L.

    1986-01-01

    A series of torque tests were performed on four flight-type hex ball universal joints in order to characterize and determine the actual load-carrying capability of this device. The universal joint is a part of manual actuation rods for scientific instruments within the Hubble Space Telescope. It was found that the hex ball will bind slightly during the initial load application. This binding did not affect the function of the universal joint, and the units would wear-in after a few additional loading cycles. The torsional yield load was approximately 50 ft-lb, and was consistent among the four test specimens. Also, the torque required to cause complete failure exceeded 80 ft-lb. It is concluded that the hex ball universal joint is suitable for its intended applications.

  20. Valve thrombosis following transcatheter aortic valve implantation: a systematic review.

    PubMed

    Córdoba-Soriano, Juan G; Puri, Rishi; Amat-Santos, Ignacio; Ribeiro, Henrique B; Abdul-Jawad Altisent, Omar; del Trigo, María; Paradis, Jean-Michel; Dumont, Eric; Urena, Marina; Rodés-Cabau, Josep

    2015-03-01

    Despite the rapid global uptake of transcatheter aortic valve implantation, valve trombosis has yet to be systematically evaluated in this field. The aim of this study was to determine the clinical characteristics, diagnostic criteria, and treatment outcomes of patients diagnosed with valve thrombosis following transcatheter aortic valve implantation through a systematic review of published data. Literature published between 2002 and 2012 on valve thrombosis as a complication of transcatheter aortic valve implantation was identified through a systematic electronic search. A total of 11 publications were identified, describing 16 patients (mean age, 80 [5] years, 65% men). All but 1 patient (94%) received a balloon-expandable valve. All patients received dual antiplatelet therapy immediately following the procedure and continued to take either mono- or dual antiplatelet therapy at the time of valve thrombosis diagnosis. Valve thrombosis was diagnosed at a median of 6 months post-procedure, with progressive dyspnea being the most common symptom. A significant increase in transvalvular gradient (from 10 [4] to 40 [12] mmHg) was the most common echocardiographic feature, in addition to leaflet thickening. Thrombus was not directly visualized with echocardiography. Three patients underwent valve explantation, and the remaining received warfarin, which effectively restored the mean transvalvular gradient to baseline within 2 months. Systemic embolism was not a feature of valve thrombosis post-transcatheter aortic valve implantation. Although a rare, yet likely under-reported complication of post-transcatheter aortic valve implantation, progressive dyspnea coupled with an increasing transvalvular gradient on echocardiography within the months following the intervention likely signifies valve thrombosis. While direct thrombus visualization appears difficult, prompt initiation of oral anticoagulation therapy effectively restores baseline valve function. Copyright © 2014

  1. JenaValve.

    PubMed

    Treede, Hendrik; Rastan, Ardawan; Ferrari, Markus; Ensminger, Stephan; Figulla, Hans-Reiner; Mohr, Friedrich-Wilhelm

    2012-09-01

    The JenaValve is a next-generation TAVI device which consists of a well-proven porcine root valve mounted on a low-profile nitinol stent. Feeler guided positioning and clip fixation on the diseased leaflets allow for anatomically correct implantation of the device without rapid pacing. Safety and efficacy of transapical aortic valve implantation using the JenaValve were evaluated in a multicentre prospective study that showed good short and midterm results. The valve was CE-mark released in Europe in September 2011. A post-market registry ensures on-going and prospective data collection in "real-world" patients. The transfemoral JenaValve delivery system will be evaluated in a first-in-man study in the near future.

  2. Depressurization valve

    DOEpatents

    Skoda, G.I.

    1989-03-28

    A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring-preferably of the Belleville variety-acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion.

  3. Novel mathematical model to estimate ball impact force in soccer.

    PubMed

    Iga, Takahito; Nunome, Hiroyuki; Sano, Shinya; Sato, Nahoko; Ikegami, Yasuo

    2017-11-22

    To assess ball impact force during soccer kicking is important to quantify from both performance and chronic injury prevention perspectives. We aimed to verify the appropriateness of previous models used to estimate ball impact force and to propose an improved model to better capture the time history of ball impact force. A soccer ball was fired directly onto a force platform (10 kHz) at five realistic kicking ball velocities and ball behaviour was captured by a high-speed camera (5,000 Hz). The time history of ball impact force was estimated using three existing models and two new models. A new mathematical model that took into account a rapid change in ball surface area and heterogeneous ball deformation showed a distinctive advantage to estimate the peak forces and its occurrence times and to reproduce time history of ball impact forces more precisely, thereby reinforcing the possible mechanics of 'footballer's ankle'. Ball impact time was also systematically shortened when ball velocity increases in contrast to practical understanding for producing faster ball velocity, however, the aspect of ball contact time must be considered carefully from practical point of view.

  4. Geologic framework and hydrogeologic characteristics of the outcrops of the Edwards and Trinity aquifers, Medina Lake area, Texas

    USGS Publications Warehouse

    Small, Ted A.; Lambert, Rebecca B.

    1998-01-01

    The Trinity aquifer, which crops out in the northern part of the Medina Lake area and underlies the Edwards aquifer in the southern part, is much less permeable and productive than the Edwards aquifer. Where the Trinity aquifer underlies the Edwards, the Trinity acts as a lower confining unit on the Edwards.

  5. Fast valve

    DOEpatents

    Van Dyke, W.J.

    1992-04-07

    A fast valve is disclosed that can close on the order of 7 milliseconds. It is closed by the force of a compressed air spring with the moving parts of the valve designed to be of very light weight and the valve gate being of wedge shaped with O-ring sealed faces to provide sealing contact without metal to metal contact. The combination of the O-ring seal and an air cushion create a soft final movement of the valve closure to prevent the fast air acting valve from having a harsh closing. 4 figs.

  6. Fast valve

    DOEpatents

    Van Dyke, William J.

    1992-01-01

    A fast valve is disclosed that can close on the order of 7 milliseconds. It is closed by the force of a compressed air spring with the moving parts of the valve designed to be of very light weight and the valve gate being of wedge shaped with O-ring sealed faces to provide sealing contact without metal to metal contact. The combination of the O-ring seal and an air cushion create a soft final movement of the valve closure to prevent the fast air acting valve from having a harsh closing.

  7. How does gravity save or kill Q-balls?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tamaki, Takashi; Sakai, Nobuyuki; Department of Education, Yamagata University, Yamagata 990-8560

    2011-02-15

    We explore stability of gravitating Q-balls with potential V{sub 4}({phi})=(m{sup 2}/2){phi}{sup 2}-{lambda}{phi}{sup 4}+({phi}{sup 6}/M{sup 2}) via catastrophe theory, as an extension of our previous work on Q-balls with potential V{sub 3}({phi})=(m{sup 2}/2){phi}{sup 2}-{mu}{phi}{sup 3}+{lambda}{phi}{sup 4}. In flat spacetime Q-balls with V{sub 4} in the thick-wall limit are unstable and there is a minimum charge Q{sub min}, where Q-balls with Qballs with arbitrarily small charge, no matter how weak gravity is. That is, gravity saves Q-balls with small charge. We also show how stabilitymore » of Q-balls changes as gravity becomes strong.« less

  8. Distribution of shape elongations of main belt asteroids derived from Pan-STARRS1 photometry

    NASA Astrophysics Data System (ADS)

    Cibulková, H.; Nortunen, H.; Ďurech, J.; Kaasalainen, M.; Vereš, P.; Jedicke, R.; Wainscoat, R. J.; Mommert, M.; Trilling, D. E.; Schunová-Lilly, E.; Magnier, E. A.; Waters, C.; Flewelling, H.

    2018-04-01

    Context. A considerable amount of photometric data is produced by surveys such as Pan-STARRS, LONEOS, WISE, or Catalina. These data are a rich source of information about the physical properties of asteroids. There are several possible approaches for using these data. Light curve inversion is a typical method that works with individual asteroids. Our approach in focusing on large groups of asteroids, such as dynamical families and taxonomic classes, is statistical; the data are not sufficient for individual models. Aim. Our aim is to study the distributions of shape elongation b/a and the spin axis latitude β for various subpopulations of asteroids and to compare our results, based on Pan-STARRS1 survey, with statistics previously carried out using various photometric databases, such as Lowell and WISE. Methods: We used the LEADER algorithm to compare the b/a and β distributions for various subpopulations of asteroids. The algorithm creates a cumulative distributive function (CDF) of observed brightness variations, and computes the b/a and β distributions with analytical basis functions that yield the observed CDF. A variant of LEADER is used to solve the joint distributions for synthetic populations to test the validity of the method. Results: When comparing distributions of shape elongation for groups of asteroids with different diameters D, we found that there are no differences for D < 25 km. We also constructed distributions for asteroids with different rotation periods and revealed that the fastest rotators with P = 0 - 4 h are more spheroidal than the population with P = 4-8 h.

  9. Photographic copy of photograph, view looking northeast of JPL Edwards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Photographic copy of photograph, view looking northeast of JPL Edwards Test Station as it looked in 1945. To the immediate right of the Test Stand 'A' tower stands a concrete monitor building or blockhouse (now Building 4203/E-4) for observation and control of tests. Other frame buildings housed workshop and administrative functions. Long structure behind automobiles was designated 4207/E-8 and was used for instrument repair and storage, a cafeteria, machine and welding shops. To the immediate south of 4207/E-8 were 4200/E-1 (used as an office and photographic laboratory) and 4205/E-6 (guardhouse, with fire extinguisher mounted on it). To the northeast of 4205/E-6 was 4204/E-5 (a propellant storage dock, with shed roof). Buildings 4200/E-1, 4205/E-6 and 4207/E-8 were demolished in 1983. Note the absence of trees. (JPL negative no. 383-1297, July 1946) - Jet Propulsion Laboratory Edwards Facility, Edwards Air Force Base, Boron, Kern County, CA

  10. The silent and apparent neurological injury in transcatheter aortic valve implantation study (SANITY): concept, design and rationale.

    PubMed

    Fanning, Jonathon P; Wesley, Allan J; Platts, David G; Walters, Darren L; Eeles, Eamonn M; Seco, Michael; Tronstad, Oystein; Strugnell, Wendy; Barnett, Adrian G; Clarke, Andrew J; Bellapart, Judith; Vallely, Michael P; Tesar, Peter J; Fraser, John F

    2014-04-05

    The incidence of clinically apparent stroke in transcatheter aortic valve implantation (TAVI) exceeds that of any other procedure performed by interventional cardiologists and, in the index admission, occurs more than twice as frequently with TAVI than with surgical aortic valve replacement (SAVR). However, this represents only a small component of the vast burden of neurological injury that occurs during TAVI, with recent evidence suggesting that many strokes are clinically silent or only subtly apparent. Additionally, insult may manifest as slight neurocognitive dysfunction rather than overt neurological deficits. Characterisation of the incidence and underlying aetiology of these neurological events may lead to identification of currently unrecognised neuroprotective strategies. The Silent and Apparent Neurological Injury in TAVI (SANITY) Study is a prospective, multicentre, observational study comparing the incidence of neurological injury after TAVI versus SAVR. It introduces an intensive, standardised, formal neurologic and neurocognitive disease assessment for all aortic valve recipients, regardless of intervention (SAVR, TAVI), valve-type (bioprosthetic, Edwards SAPIEN-XT) or access route (sternotomy, transfemoral, transapical or transaortic). Comprehensive monitoring of neurological insult will also be recorded to more fully define and compare the neurological burden of the procedures and identify targets for harm minimisation strategies. The SANITY study undertakes the most rigorous assessment of neurological injury reported in the literature to date. It attempts to accurately characterise the insult and sustained injury associated with both TAVI and SAVR in an attempt to advance understanding of this complication and associations thus allowing for improved patient selection and procedural modification.

  11. The silent and apparent neurological injury in transcatheter aortic valve implantation study (SANITY): concept, design and rationale

    PubMed Central

    2014-01-01

    Background The incidence of clinically apparent stroke in transcatheter aortic valve implantation (TAVI) exceeds that of any other procedure performed by interventional cardiologists and, in the index admission, occurs more than twice as frequently with TAVI than with surgical aortic valve replacement (SAVR). However, this represents only a small component of the vast burden of neurological injury that occurs during TAVI, with recent evidence suggesting that many strokes are clinically silent or only subtly apparent. Additionally, insult may manifest as slight neurocognitive dysfunction rather than overt neurological deficits. Characterisation of the incidence and underlying aetiology of these neurological events may lead to identification of currently unrecognised neuroprotective strategies. Methods The Silent and Apparent Neurological Injury in TAVI (SANITY) Study is a prospective, multicentre, observational study comparing the incidence of neurological injury after TAVI versus SAVR. It introduces an intensive, standardised, formal neurologic and neurocognitive disease assessment for all aortic valve recipients, regardless of intervention (SAVR, TAVI), valve-type (bioprosthetic, Edwards SAPIEN-XT) or access route (sternotomy, transfemoral, transapical or transaortic). Comprehensive monitoring of neurological insult will also be recorded to more fully define and compare the neurological burden of the procedures and identify targets for harm minimisation strategies. Discussion The SANITY study undertakes the most rigorous assessment of neurological injury reported in the literature to date. It attempts to accurately characterise the insult and sustained injury associated with both TAVI and SAVR in an attempt to advance understanding of this complication and associations thus allowing for improved patient selection and procedural modification. PMID:24708720

  12. Tricuspid valve and percutaneous approach: No longer the forgotten valve!

    PubMed

    Bouleti, Claire; Juliard, Jean-Michel; Himbert, Dominique; Iung, Bernard; Brochet, Eric; Urena, Marina; Dilly, Marie-Pierre; Ou, Phalla; Nataf, Patrick; Vahanian, Alec

    2016-01-01

    Tricuspid valve disease is mainly represented by tricuspid regurgitation (TR), which is a predictor of poor outcome. TR is usually secondary, caused by right ventricle pressure or volume overload, the leading cause being left-sided heart valve diseases. Tricuspid surgery for severe TR is recommended during left valve surgery, and consists of either a valve replacement or, most often, a tricuspid repair with or without prosthetic annuloplasty. When TR persists or worsens after left valvular surgery, redo isolated tricuspid surgery is associated with high mortality. In addition, a sizeable proportion of patients present with tricuspid surgery deterioration over time, and need a reintervention, which is associated with high morbi-mortality rates. In this context, and given the recent major breakthrough in the percutaneous treatment of aortic and mitral valve diseases, the tricuspid valve appears an appealing challenge, although it raises specific issues. The first applications of transcatheter techniques for tricuspid valve disease were valve-in-valve and valve-in-ring implantation for degenerated bioprosthesis or ring annuloplasty. Some concerns remain regarding prosthesis sizing, rapid ventricular pacing and the best approach, but these procedures appear to be safe and effective. More recently, bicuspidization using a transcatheter approach for the treatment of native tricuspid valve has been published, in two patients. Finally, other devices are in preclinical development. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  13. Depressurization valve

    DOEpatents

    Skoda, George I.

    1989-01-01

    A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring--preferably of the Belleville variety--acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion. The latch plate in surrounding the stem is limited in its outward movement by a boss attached to the stem at the end of

  14. Acting Administrator Lightfoot Visits Ball Aerospace

    NASA Image and Video Library

    2017-04-06

    Acting NASA Deputy Administrator Lesa Roe, right, speaks with Rob Strain, president of Ball Aerospace, Thursday, April 6, 2017 during a visit to Ball Aerospace in Boulder, Colo. Photo Credit: (NASA/Joel Kowsky)

  15. Application of coordinate transform on ball plate calibration

    NASA Astrophysics Data System (ADS)

    Wei, Hengzheng; Wang, Weinong; Ren, Guoying; Pei, Limei

    2015-02-01

    For the ball plate calibration method with coordinate measurement machine (CMM) equipped with laser interferometer, it is essential to adjust the ball plate parallel to the direction of laser beam. It is very time-consuming. To solve this problem, a method based on coordinate transformation between machine system and object system is presented. With the fixed points' coordinates of the ball plate measured in the object system and machine system, the transformation matrix between the coordinate systems is calculated. The laser interferometer measurement data error due to the placement of ball plate can be corrected with this transformation matrix. Experimental results indicate that this method is consistent with the handy adjustment method. It avoids the complexity of ball plate adjustment. It also can be applied to the ball beam calibration.

  16. Aerodynamic drag of modern soccer balls.

    PubMed

    Asai, Takeshi; Seo, Kazuya

    2013-12-01

    Soccer balls such as the Adidas Roteiro that have been used in soccer tournaments thus far had 32 pentagonal and hexagonal panels. Recently, the Adidas Teamgeist II and Adidas Jabulani, respectively having 14 and 8 panels, have been used at tournaments; the aerodynamic characteristics of these balls have not yet been verified. Now, the Adidas Tango 12, having 32 panels, has been developed for use at tournaments; therefore, it is necessary to understand its aerodynamic characteristics. Through a wind tunnel test and ball trajectory simulations, this study shows that the aerodynamic resistance of the new 32-panel soccer ball is larger in the high-speed region and lower in the middle-speed region than that of the previous 14- and 8-panel balls. The critical Reynolds number of the Roteiro, Teamgeist II, Jabulani, and Tango 12 was ~2.2 × 10(5) (drag coefficient, C d  ≈ 0.12), ~2.8 × 10(5) (C d  ≈ 0.13), ~3.3 × 10(5) (C d  ≈ 0.13), and ~2.4 × 10(5) (C d  ≈ 0.15), respectively. The flight trajectory simulation suggested that the Tango 12, one of the newest soccer balls, has less air resistance in the medium-speed region than the Jabulani and can thus easily acquire large initial velocity in this region. It is considered that the critical Reynolds number of a soccer ball, as considered within the scope of this experiment, depends on the extended total distance of the panel bonds rather than the small designs on the panel surfaces.

  17. Timing of anticoagulant re-initiation following intracerebral hemorrhage in mechanical heart valves: Survey of neurosurgeons and thrombosis experts.

    PubMed

    AlKherayf, Fahad; Xu, Yan; Westwick, Harrison; Moldovan, Ioana Doina; Wells, Philip S

    2017-03-01

    While oral anticoagulation (OAC) is universally indicated for patients with mechanical heart valves (MHVs), OAC resumption following anticoagulant-associated intracerebral hemorrhage (ICH) is an area of uncertainty. We sought to determine the practice preferences of North American neurosurgeons and thrombosis experts on optimal timing of OAC re-initiation. A cross-sectional survey was disseminated to North American members of the American Association of Neurological Surgeons and the International Society for Thrombosis and Haemostasis. Demographic factors, as well as a clinical scenario with 14 modifiable clinical risk factors were included in the survey. 504 physicians completed our survey (response rate 34.3%). Majority of participants were affiliated with academic centres, and managed≤10 ICH patients with MHV per year. There was wide distribution in response in optimal timing for OAC resumption following an ICH: 59% and 60% preferred to re-start OAC between 3 and 14 days following the hemorrhagic event (median of 6-7 days). Smaller hemorrhages (<30cm 2 ). CHADS 2 score ≥2, concomitant venous thromboembolism, mitral valve prosthesis, caged-ball valves and multiple valves prompted earlier OAC resumption. Wide variation in the current practice of neurosurgeons and thrombosis specialists exist when they encounter patients with ICH and MHV, though decisions were influenced by patient- and valve-related factors. As our observed variation likely reflects the immense gap in current evidence, prospective randomized trials in this population are therefore urgently needed. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Kinetic study of ferronickel slag grinding at variation of ball filling and ratio of feed to grinding balls

    NASA Astrophysics Data System (ADS)

    Sanwani, Edy; Ikhwanto, Muhammad

    2017-01-01

    The objective of this paper is to investigate the effect of ball filling and ratio of feed to grinding balls on the kinetic of grinding of ferronickel slag in a laboratory scale ball mill. The experiments were started by crushing the ferronickel slag samples using a roll crusher to produce -3 mesh (-6.7 mm) product. This product, after sampling and sample dividing processes, was then used as feed for grinding process. The grinding was performed with variations of ball filling and ratio of feed to grinding balls for 150 minutes. At every certain time interval, particle size analysis was carried out on the grinding product. The results of the experiments were also used to develop linear regression model of the effect of grinding variables on the P80 of the product. Based on this study, it was shown that P80 values of the grinding products declined sharply until 70 minutes of grinding time due to the dominant mechanism of impact breakage and then decreased slowly after 70 minutes until 150 minutes of grinding time due to dominant mechanism of attrition breakage. Kinetics study of the grinding process on variations of grinding ball filling showed that the optimum rate of formation of fine particles for 20%, 30%, 40% and 50% mill volume was achieved at a particle size of 400 µm in which the best initial rate of formation occurred at 50% volume of mill. At the variations of ratio of feed to grinding balls it was shown that the optimum rate of grinding for the ratio of 1:10, 1: 8 and 1: 6 was achieved at a particle size of 400 µm and for the ratio of 1: 4 was at 841 µm in which the best initial rate of formation occurred at a 1:10 ratio. In this study, it was also produced two regression models that can predict the P80 value of the grinding product as a function of the variables of grinding time, ball filling and the ratio of the feed to grinding balls.

  19. Biomechanical Analysis of Weighted-Ball Exercises for Baseball Pitchers.

    PubMed

    Fleisig, Glenn S; Diffendaffer, Alek Z; Aune, Kyle T; Ivey, Brett; Laughlin, Walter A

    Weighted-ball throwing programs are commonly used in training baseball pitchers to increase ball velocity. The purpose of this study was to compare kinematics and kinetics among weighted-ball exercises with values from standard pitching (ie, pitching standard 5-oz baseballs from a mound). Ball and arm velocities would be greater with lighter balls and joint kinetics would be greater with heavier balls. Controlled laboratory study. Twenty-five high school and collegiate baseball pitchers experienced with weighted-ball throwing were tested with an automated motion capture system. Each participant performed 3 trials of 10 different exercises: pitching 4-, 5-, 6-, and 7-oz baseballs from a mound; flat-ground crow hop throws with 4-, 5-, 6-, and 7-oz baseballs; and flat-ground hold exercises with 14- and 32-oz balls. Twenty-six biomechanical parameters were computed for each trial. Data among the 10 exercises were compared with repeated measures analysis of variance and post hoc paired t tests against the standard pitching data. Ball velocity increased as ball mass decreased. There were no differences in arm and trunk velocities between throwing a standard baseball and an underweight baseball (4 oz), while arm and trunk velocities steadily decreased as ball weight increased from 5 to 32 oz. Compared with values pitching from a mound, velocities of the pelvis, shoulder, and ball were increased for flat-ground throws. In general, as ball mass increased arm torques and forces decreased; the exception was elbow flexion torque, which was significantly greater for the flat-ground holds. There were significant differences in body positions when pitching on the mound, flat-ground throws, and holds. While ball velocity was greatest throwing underweight baseballs, results from the study did not support the rest of the hypothesis. Kinematics and kinetics were similar between underweight and standard baseballs, while overweight balls correlated with decreased arm forces, torques

  20. Bending stresses in spherically hollow ball bearing and fatigue experiments

    NASA Technical Reports Server (NTRS)

    Nypan, L. J.; Coe, H. H.; Parker, R. J.

    1975-01-01

    Spherically hollow balls of 21.7, 50.0, and 56.5 percent mass reduction were operated in ball bearings and in a five-ball fatigue tester with differing outcomes. Available theoretical and experimental treatments of stresses in spherically hollow balls are reviewed and compared. Bending stresses are estimated for these spherically hollow balls to better understand the differences in ball bearing and fatigue test experience.

  1. Bending stresses in spherically hollow ball bearing and fatigue experiments

    NASA Technical Reports Server (NTRS)

    Nypan, L. J.; Coe, H. H.; Parker, R. J.

    1975-01-01

    Spherically hollow balls of 21.7, 50.0 and 56.5 per cent mass reduction have been operated in ball bearings and in a 5-ball fatigue tester with differing outcomes. Available theoretical and experimental treatments of stresses in spherically hollow balls are reviewed and compared. Bending stresses are estimated for these spherically hollow balls to better understand the differences in ball bearing and fatigue test experience.

  2. Excess flow shutoff valve

    DOEpatents

    Kiffer, Micah S.; Tentarelli, Stephen Clyde

    2016-02-09

    Excess flow shutoff valve comprising a valve body, a valve plug, a partition, and an activation component where the valve plug, the partition, and activation component are disposed within the valve body. A suitable flow restriction is provided to create a pressure difference between the upstream end of the valve plug and the downstream end of the valve plug when fluid flows through the valve body. The pressure difference exceeds a target pressure difference needed to activate the activation component when fluid flow through the valve body is higher than a desired rate, and thereby closes the valve.

  3. Ball to separator contact forces in angular contact ball bearings under thrust and radial loads

    NASA Technical Reports Server (NTRS)

    Nypan, L. J.

    1978-01-01

    Experimental data are reported on ball to cage contact forces in a 110 mm bore ball bearing operating at speeds to 12,000 rpm under radial and thrust loads. Information is also reported on cage to inner race land contact force, cage to inner race land clearance, and cage to shaft speed ratios.

  4. Ball to separator contact forces in angular contact ball bearings under thrust and radial loads

    NASA Technical Reports Server (NTRS)

    Nypan, L. J.

    1977-01-01

    Experimental data is reported on ball to cage contact forces in a 110 mm bore ball bearing operating at speeds to 12000 rpm under radial and thrust loads. Information is also reported on cage to inner race land contact force, cage to inner race land clearance, and cage to shaft speed ratios.

  5. Ball Lightning in Zero Gravity in the Laboratory

    NASA Astrophysics Data System (ADS)

    Alexeff, Igor; Parameswaran, Sriram; Grace, Michael

    2004-11-01

    We have created balls of orange plasma in atmospheric - pressure air that survive for over 1/2 second without power input. The technique used was to create a pulsed horizontal electric arc in a zero - gravity environment using 6 neon - sign transformers in parallel, each producing 16,000 V at 60 mA. The zero - gravity environment reduces heat losses by reducing thermal convection, creating a larger ball. Previous work (1) suggests that the ball lifetime scales as the square of the ball radius. The balls were photographed after power turnoff with a high - speed 16 mm movie camera. Movies of the balls being formed and decaying will be shown. We suggest that there are several other forms of ball lightning (2). 1.Igor Alexeff et. al. International Conference On Plasma Science, Jeju, Korea, June 2-5, 2003, Conference Record, p 254. 2. Igor Alexeff and Mark Rader, IEEE Transactions on Plasma Science, Vol. 20, No. 6, Dec. 1992, pp.669-671. Igor Alexeff and Mark Rader, Fusion Technology, Vol. 27, May 1995, p. 271.

  6. Apparatus and method for inspecting a bearing ball

    NASA Technical Reports Server (NTRS)

    Bankston, B. F. (Inventor)

    1985-01-01

    A method and apparatus for inspecting the surface of a ball bearing is disclosed which includes a base having a high friction non-abrasive base scanning surface. A holding device includes a cone-shaped cup recess in which a ball element is received. Air is introduced through a passage to relieve friction between the wall of the recess and the ball element and facilitate rolling of the ball over the high friction base surface. The holding device is moved over the base scanning surface in a predetermined pattern such that the entire surface of the ball element is inspected byan eddy current probe which detects any surface defects.

  7. Experimental evaluation of stresses in spherically hollow balls

    NASA Technical Reports Server (NTRS)

    Nypan, L. J.

    1974-01-01

    An analysis was undertaken to evaluate stresses within spherically hollow ball bearings proportioned for 40, 50, and 60% mass reductions. Strain gage rosettes were used to determine principal strains and stresses in the steel ball models statically loaded in various orientations. Dimensionless results are reported for the balls under flate plate contact loads. Similitude considerations permit these results to be applied to calculate stresses in hollow ball bearings proportioned to these mass reductions.

  8. Behaviour of a Bouncing Ball

    ERIC Educational Resources Information Center

    Cross, Rod

    2015-01-01

    The bounce of a ball is a seemingly innocuous event that can be used to illustrate many aspects of elementary and even advanced mechanics. Both normal and oblique bounces on a rigid surface are considered in this article, emphasizing qualitative features of the bounce process. If the ball bounces at an oblique angle then it can slide throughout…

  9. Reflections on a Bouncing Ball

    ERIC Educational Resources Information Center

    Rohr, Jim; Lopez, Veronica; Rohr, Tyler

    2014-01-01

    While observing the bounce heights of various kinds of sports balls dropped from different heights onto a variety of surfaces, we thought of the following question: Could measurements of drop and bounce heights of balls of different diameters, but of the same material, falling from different heights, but on the same surface, be expressed by a…

  10. Accuracy and Reliability of a New Tennis Ball Machine

    PubMed Central

    Brechbuhl, Cyril; Millet, Grégoire; Schmitt, Laurent

    2016-01-01

    The aim was to evaluate the reliability of a newly-developed ball machine named 'Hightof', on the field and to assess its accuracy. The experiment was conducted in the collaboration of the 'Hawk-Eye' technology. The accuracy and reliability of this ball machine were assessed during an incremental test, with 1 min of exercise and 30 sec of recovery, where the frequency of the balls increased from 10 to 30 balls·min-1. The initial frequency was 10 and increased by 2 until 22, then by 1 until 30 balls·min-1. The reference points for the impact were 8.39m from the net and 2.70m from lateral line for the right side and 2.83m for the left side. The precision of the machine was similar on the right and left sides (0.63 ± 0.39 vs 0.63 ± 0.34 m). The distances to the reference point were 0.52 ± 0.42, 0.26 ± 0.19, 0.52 ± 0.37, 0.28 ± 0.19 m for the Y-right, X-right, Y-left and X-left impacts. The precision was constant and did not increase with the intensity. (e.g ball frequency). The ball velocity was 86.3 ± 1.5 and 86.5 ± 1.3 km·h-1 for the right and the left side, respectively. The coefficient of variation for the velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min-1). Conclusion: both the accuracy and the reliability of this new ball machine appear satisfying enough for field testing and training. Key points The reliability and accuracy of a new ball machine named 'Hightof' were assessed. The impact point was reproducible and similar on the right and left sides (±0.63 m). The precision was constant and did not increase with the intensity (e.g ball frequency). The coefficient of variation of the ball velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min-1). PMID:27274663

  11. Accuracy and Reliability of a New Tennis Ball Machine.

    PubMed

    Brechbuhl, Cyril; Millet, Grégoire; Schmitt, Laurent

    2016-06-01

    The aim was to evaluate the reliability of a newly-developed ball machine named 'Hightof', on the field and to assess its accuracy. The experiment was conducted in the collaboration of the 'Hawk-Eye' technology. The accuracy and reliability of this ball machine were assessed during an incremental test, with 1 min of exercise and 30 sec of recovery, where the frequency of the balls increased from 10 to 30 balls·min(-1). The initial frequency was 10 and increased by 2 until 22, then by 1 until 30 balls·min(-1). The reference points for the impact were 8.39m from the net and 2.70m from lateral line for the right side and 2.83m for the left side. The precision of the machine was similar on the right and left sides (0.63 ± 0.39 vs 0.63 ± 0.34 m). The distances to the reference point were 0.52 ± 0.42, 0.26 ± 0.19, 0.52 ± 0.37, 0.28 ± 0.19 m for the Y-right, X-right, Y-left and X-left impacts. The precision was constant and did not increase with the intensity. (e.g ball frequency). The ball velocity was 86.3 ± 1.5 and 86.5 ± 1.3 km·h(-1) for the right and the left side, respectively. The coefficient of variation for the velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min(-1)). both the accuracy and the reliability of this new ball machine appear satisfying enough for field testing and training. Key pointsThe reliability and accuracy of a new ball machine named 'Hightof' were assessed.The impact point was reproducible and similar on the right and left sides (±0.63 m).The precision was constant and did not increase with the intensity (e.g ball frequency).The coefficient of variation of the ball velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min(-1)).

  12. Geologic framework and hydrogeologic characteristics of the Edwards Aquifer outcrop, Comal County, Texas

    USGS Publications Warehouse

    Small, T.A.; Hanson, J.A.

    1994-01-01

    In Comal County, the Edwards aquifer is probably most vulnerable to surface contamination in the rapidly urbanizing areas on the Edwards aquifer outcrop. Possible contamination can result from spills, leakage of hazardous materials, or runoff onto the intensely faulted and fractured, karstic limestone outcrops characteristic of the recharge zone.

  13. Absence of posterior tricuspid valve leaflet and valve reconstruction

    PubMed Central

    Komoda, Takeshi; Stamm, Christof; Fleck, Eckart; Hetzer, Roland

    2012-01-01

    We report a rare case of the absence of a posterior tricuspid valve leaflet. A male patient, aged 46, suffering from severe tricuspid valve regurgitation (TR) of unknown aetiology and atrial septal aneurysm was referred to our hospital for surgery. On surgical inspection, the posterior tricuspid valve leaflet and its subvalvular apparatus were completely absent and only the valve annulus was seen in the corresponding position. The anterior and septal leaflets were normal. We successfully reconstructed the tricuspid valve as follows: the head of an anterior papillary muscle was approximated to the ventricular septum (Sebening stitch). After the approximation of the centre of the tricuspid annulus of the anterior leaflet to the tricuspid annulus on the opposite side, a sizer of 29 mm in diameter was easily passed through the anterior orifice. The posterior orifice was closed with running sutures (posterior annulorrhaphy after Hetzer). Before these procedures, we attempted to reconstruct the tricuspid valve with a posterior annulorrhaphy alone; however, valve competence was insufficient. A Sebening stitch was necessary to improve the valve competence. Echocardiography showed TR grade 1 at the patient's discharge from hospital and TR grade 1 to 2 at the follow-up, 10 months after the operation. PMID:22419794

  14. [Percutaneously implantable aortic valve: the JenaValve concept evolution].

    PubMed

    Figulla, Hans R; Ferrari, Markus

    2006-10-01

    Due to the increasing incidence of severe aortic stenosis in old and multimorbid patients, the percutaneous implantation of aortic valve-carrying stents has become an alternative to the surgical replacement of aortic valves. Starting in 1995, the authors developed a self-expanding stent which transferred the necessary forces for anchoring up to the aorta ascendens-a conception taken over from CoreValve. The further improvement of this idea over the past 11 years has led to a self-expanding, relatively short stent-valve system that is reliably positioned in the cusps of the old aortic valve and holds the old valve like a paper clip, thus transferring the holding forces physiologically. As compared to conventional systems, the sophisticated insertion catheter requires further chronic animal tests so as to represent a true alternative to the conventional surgical procedure.

  15. Effects of BOSU ball(s) during sit-ups with body weight and added resistance on core muscle activation.

    PubMed

    Saeterbakken, Atle H; Andersen, Vidar; Jansson, June; Kvellestad, Ann C; Fimland, Marius S

    2014-12-01

    The objective of this study was to assess the electromyographic activity of the rectus abdominis (upper and lower part) and external oblique during sit-ups performed on BOSU ball(s). Twenty-four men participated in a familiarization session, and in the next session, they performed the experimental tests in randomized order. The sit-ups were performed with 10 repetitions with body weight and with 10 repetition maximum (10RM) using elastic bands as external resistance under 4 different conditions: (a) on a stable surface, (b) with the BOSU ball under their feet (dome side down, lower-body instability), (c) BOSU ball under the low back (dome side up, upper-body instability), and (d) with BOSU balls under both feet and the low back (dual instability). The feet were not attached to the surface. We observed that with body weight, external oblique activation was decreased by upper-body instability and dual instability by 22-24% (p = 0.002-0.006), whereas the rectus abdominis was not affected by the surface. Using 10RM loads, the upper and lower rectus abdominis activities were increased by upper body and dual instability by 21-24% compared with that for a stable surface (P ≤ 0.001-0.036). Further, lower-body instability did not affect muscle activities significantly with either load for any condition. Hence, BOSU balls under the low back can increase and decrease abdominal muscle activation depending on the load, whereas placing a BOSU ball under the feet with the dome side down had little impact.

  16. Prince Edward Island Heart Health Dissemination Research Project: establishing a sustainable community mobilization initiative.

    PubMed

    White, R; Mitchell, T; Gyorfi-Dyke, E; Sweet, L; Hebert, R; Moase, O; MacPhee, R; MacDonald, B

    2001-01-01

    This paper provides an overview of the Prince Edward Island Heart Health Program (PEIHHP) Dissemination Research Project. Prince Edward Island (PEI) is a small province in the Atlantic region of Canada with a population of 137,980. The Island's economy is dependent on the fishery, agriculture, and tourism industries. Although unemployment rates are high (14.4%), Prince Edward Island has the lowest poverty rate in the country at 15.2%, high levels of social support (86%), and the second lowest rate of high chronic stress (Report on the Health of Canadians, 1996, 1999).

  17. The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS)

    PubMed Central

    Ursano, Robert J.; Colpe, Lisa J.; Heeringa, Steven G.; Kessler, Ronald C.; Schoenbaum, Michael; Stein, Murray B.

    2014-01-01

    Importance/Objective Although the suicide rate in the U.S. Army has traditionally been below age-gender matched civilian rates, it has climbed steadily since the beginning of the Iraq and Afghanistan conflicts and since 2008 has exceeded the demographically matched civilian rate. The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) is a multicomponent epidemiological and neurobiological study designed to generate actionable evidence-based recommendations to reduce Army suicides and increase knowledge about risk and resilience factors for suicidality and its psychopathological correlates. This paper presents an overview of the Army STARRS component study designs and of recent findings. Design/Setting/Participants/Intervention Army STARRS includes six main component studies: (1) the Historical Administrative Data Study (HADS) of Army and Department of Defense (DoD) administrative data systems (including records of suicidal behaviors) for all soldiers on active duty 2004–2009 aimed at finding administrative record predictors of suicides; (2) retrospective case-control studies of fatal and nonfatal suicidal behaviors (each planned to have n = 150 cases and n = 300 controls); (3) a study of new soldiers (n = 50,765 completed surveys) assessed just before beginning basic combat training (BCT) with self-administered questionnaires (SAQ), neurocognitive tests, and blood samples; (4) a cross-sectional study of approximately 35,000 (completed SAQs) soldiers representative of all other (i.e., exclusive of BCT) active duty soldiers; (5) a pre-post deployment study (with blood samples) of soldiers in brigade combat teams about to deploy to Afghanistan (n = 9,421 completed baseline surveys), with sub-samples assessed again one, three, and nine months after returning from deployment; and (6) a pilot study to follow-up SAQ respondents transitioning to civilian life. Army/DoD administrative data are being linked prospectively to the large-scale survey

  18. The Army study to assess risk and resilience in servicemembers (Army STARRS).

    PubMed

    Ursano, Robert J; Colpe, Lisa J; Heeringa, Steven G; Kessler, Ronald C; Schoenbaum, Michael; Stein, Murray B

    2014-01-01

    IMPORTANCE/OBJECTIVE: Although the suicide rate in the U.S. Army has traditionally been below age-gender matched civilian rates, it has climbed steadily since the beginning of the Iraq and Afghanistan conflicts and since 2008 has exceeded the demographically matched civilian rate. The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) is a multicomponent epidemiological and neurobiological study designed to generate actionable evidence-based recommendations to reduce Army suicides and increase knowledge about risk and resilience factors for suicidality and its psychopathological correlates. This paper presents an overview of the Army STARRS component study designs and of recent findings. DESIGN/SETTING/PARTICIPANTS/INTERVENTION: Army STARRS includes six main component studies: (1) the Historical Administrative Data Study (HADS) of Army and Department of Defense (DoD) administrative data systems (including records of suicidal behaviors) for all soldiers on active duty 2004-2009 aimed at finding administrative record predictors of suicides; (2) retrospective case-control studies of fatal and nonfatal suicidal behaviors (each planned to have n = 150 cases and n = 300 controls); (3) a study of new soldiers (n = 50,765 completed surveys) assessed just before beginning basic combat training (BCT) with self-administered questionnaires (SAQ), neurocognitive tests, and blood samples; (4) a cross-sectional study of approximately 35,000 (completed SAQs) soldiers representative of all other (i.e., exclusive of BCT) active duty soldiers; (5) a pre-post deployment study (with blood samples) of soldiers in brigade combat teams about to deploy to Afghanistan (n = 9,421 completed baseline surveys), with sub-samples assessed again one, three, and nine months after returning from deployment; and (6) a pilot study to follow-up SAQ respondents transitioning to civilian life. Army/DoD administrative data are being linked prospectively to the large-scale survey

  19. Astronaut Edward Gibson sails through airlock module hatch

    NASA Image and Video Library

    1974-02-01

    SL4-150-5074 (February 1974) --- Scientist-astronaut Edward G. Gibson, science pilot for the Skylab 4 mission, demonstrates the effects of zero-gravity as he sails through airlock module hatch. Photo credit: NASA

  20. Brenda K. Edwards, PhD | DCCPS/NCI/NIH

    Cancer.gov

    Brenda K. Edwards, PhD, has been with the Surveillance Research Program (SRP) and its predecessor organizations at the National Cancer Institute (NCI) since 1989, serving as SRP’s Associate Director from 1990-2011.

  1. Ball Screw Actuator Including an Axial Soft Stop

    NASA Technical Reports Server (NTRS)

    Forrest, Steven Talbert (Inventor); Woessner, George (Inventor); Abel, Steve (Inventor); Wingett, Paul T. (Inventor); Hanlon, Casey (Inventor)

    2016-01-01

    An actuator includes an actuator housing, a ball screw, and an axial soft stop assembly. The ball screw extends through the actuator housing and has a first end and a second end. The ball screw is coupled to receive a drive force and is configured, upon receipt of the drive force, to selectively move in a retract direction and an extend direction. The axial soft stop assembly is disposed within the actuator housing. The axial soft stop assembly is configured to be selectively engaged by the ball screw and, upon being engaged thereby, to translate, with compliance, a predetermined distance in the extend direction, and to prevent further movement of the ball screw upon translating the predetermined distance.

  2. Outcome of bioprosthetic valve replacement in dogs with tricuspid valve dysplasia.

    PubMed

    Bristow, P; Sargent, J; Luis Fuentes, V; Brockman, D

    2017-04-01

    To describe the short-term and long-term outcome in dogs with tricuspid valve dysplasia undergoing tricuspid valve replacement under cardiopulmonary bypass. Data were collected from the hospital records of all dogs that had undergone tricuspid valve replacement under cardiopulmonary bypass between 2006 and 2012. Dogs were considered candidates for tricuspid valve replacement if they had severe tricuspid valve regurgitation associated with clinical signs of cardiac compromise. Nine dogs of six different breeds were presented. Median age was 13 months (range 7 to 61 months), median weight 26·5 kg (range 9·7 to 59 kg). Eight bovine pericardial valves and one porcine aortic valve were used. One non-fatal intraoperative complication occurred. Complications during hospitalisation occurred in six dogs, four of which were fatal. Of the five dogs discharged, one presented dead due to haemothorax after minor trauma seven days later. The four remaining dogs survived a median of 533 days; all of these dogs received a bovine pericardial valve. Based on our results, tricuspid valve replacement with bovine or porcine prosthetic valves is associated with a high incidence of complications. © 2017 British Small Animal Veterinary Association.

  3. Environmental Assessment of Lead at Camp Edwards, Massachusetts, Small Arms Ranges

    DTIC Science & Technology

    2007-08-01

    phosphates in soils as a method to immobilize lead. Environmental Science and Technology. 28(4):646–654. Rühling, A., and G. Tyler. 1973. Heavy metal ...control of heavy metals in a sandy soil . Environmental Science and Technology. 36(22):4804– 4810. Xia, K., W. Bleam, and P. A. Helmke. 1997. Studies...Military Training Sources of Lead and Soil Distribution at Camp Edwards ..............38 3.3 Projects Specific to Camp Edwards Small Arms Ranges

  4. Giddings Edwards (Cretaceous) field, south Texas: carbonate channel or elongate buildup

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lomando, A.J.; Mazzullo, S.J.

    1989-03-01

    Giddings Edwards field, located in Fayette County, Texas, is situated on the broad Cretaceous (Albian) shallow shelf, approximately 20 mi north of the main Edwards shelf-margin reef trend. The Giddings field produces gas from an elongate stratigraphic trap approximately 9.5 mi long and 1.8 mi wide, encased in argillaceous lime mudstones and shales; the field is oriented normal to the contiguous Edwards reef trend. Available cores and cuttings samples from the central portion of the field indicate that the field reservoir is composed of biopackstones and grainstones interpreted to have been deposited in a high-energy shelf environment. The facies systemmore » is characterized by stacked reservoirs having a maximum gross pay thickness of over 100 ft, containing primary interparticle and secondary biomoldic porosity, both of which have been modified slightly by chemical compaction and partial occlusion by sparry calcite and saddle dolomite cements. Despite reasonable subsurface sample and mechanical log control within and surrounding the field, its depositional origin remains equivocal. Such uncertainty has important bearing on predictive models for the exploration for additional Edwards shelfal hydrocarbon reservoirs. The elongate, biconvex geometry of the productive carbonate sands, their northward thinning, and apparent updip bifurcation suggest deposition in a shallow-shelf channel system. By contrast, an alternative correlation and interpretation based on geometry and facies is that of an elongate in-situ carbonate buildup. A number of modern analogs of elongate buildups normal to major reef systems are available from which to compare and model the depositional system of Giddings Edwards field. The evaluation of this field serves as an example of using a multiple working hypothesis to develop an accurate exploration model.« less

  5. Early Outcomes for Valve-in-valve Transcatheter Aortic Valve Replacement in Degenerative Freestyle Bioprostheses.

    PubMed

    Sang, Stephane Leung Wai; Beute, Tyler; Heiser, John; Berkompas, Duane; Fanning, Justin; Merhi, William

    2017-11-20

    Transcatheter aortic valve replacement (TAVR) is used increasingly to treat bioprosthetic valve failure. A paucity of data exists regarding valve-in-valve (ViV) TAVR in degenerated Freestyle stentless bioprostheses (FSBs). This study sought to evaluate the feasibility and short-term outcomes of ViV TAVR in previously placed FSB. From October 2014 to September 2016, 22 patients at a single institution underwent ViV TAVR with a self-expanding transcatheter valve for a failing FSB. Patient baseline characteristics and clinical outcomes data were collected retrospectively and entered into a dedicated database. The mean patient age was 74 ± 9years, and the mean Society of Thoracic Surgeons' Risk score was 9.0 ± 7.4%. Ten patients presented with acute heart failure requiring urgent intervention. The most common mode of failure of the FSB was regurgitation caused by a flail or malcoapting leaflet. Seventeen (77%) patients had a modified subcoronary implantation, 3 (14%) had a full root replacement, and 2 (9%) had a root inclusion. Device success using a self-expanding transcatheter valve was 95%, all via transfemoral approach. The mean implant depth was 7 ± 3 mm. Thirty-day survival was 100%. No patient had more than mild paravalvular regurgitation at 30days, and the permanent pacemaker rate was 9%. The mean hospital stay after intervention was 5 ± 2days. ViV TAVR using a self-expanding transcatheter valve is safe, feasible, and can be used successfully to treat a failed FSB. Procedural challenges suggest referral to valve centers of excellence. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Prince Edward Island. Reference Series No. 33.

    ERIC Educational Resources Information Center

    Department of External Affairs, Ottawa (Ontario).

    This booklet, one of a series featuring the Canadian provinces, presents a brief overview of Prince Edward Island and is suitable for teacher reference or student reading. Separate sections discuss geography, climate, history, early trade, development, agriculture, the potato industry, forests, fisheries, aquaculture, industry, tourism, energy,…

  7. Geologic Map of the Edwards Aquifer In Northern Medina and Northeastern Uvalde Counties, South-central Texas

    USGS Publications Warehouse

    Clark, Allan K.; Faith, Jason R.; Blome, Charles D.; Pedraza, Diana E.

    2006-01-01

    The southern segment of the Edwards aquifer in south-central Texas is one of the most productive subsurface reservoirs of potable water in the world, providing water of excellent quality to more than a million people in the San Antonio region, where the Environmental Protection Agency (EPA) has declared it to be a sole-source aquifer (van der Leeden and others, 1990). Depending on the depositional province within which the associated carbonate rocks originated (Maclay and Small, 1984), the Edwards aquifer is composed of several geologic formations (primarily limestone and dolostone) of Early Cretaceous age. Most water pumped from the Edwards aquifer comes form the Person and Kainer Formations, which were deposited over the San Marcos Platform. The principal source of ground water in study area is the Devils River Formation, which was deposited in the Devils River trend. The Devils River Formation provides large quantities of irrigation water to fertile bottomland areas of Medina and Uvalde Counties, where the success of farming and ranching activities has long depended upon water from the Edwards aquifer. The study area includes all of the Edwards aquifer recharge zone between the Sabinal River (on the west) and the Medina River (on the east) plus an updip fringe of the confined zone in east-central Uvalde and central Medina Counties. Over about ninety percent of the study area--within the Devils River trend--the Edwards aquifer is composed of the Georgetown Formation plus the underlying Devils River Formation. Over the remaining area--over the southwestern margin of the San Marcos platform--the Edwards aquifer consists of the Georgetown Formation plus the underlying Edwards Group (Rose, 1972), which comprises the Kainer and Person Formations.

  8. Antenatal detection of Edwards (Trisomy 18) and Patau (Trisomy 13) syndrome: England and Wales 2005-2012.

    PubMed

    Springett, Anna L; Morris, Joan K

    2014-09-01

    Pregnancies with Edwards or Patau syndrome are often detected through screening for Down's syndrome. We aimed to evaluate the impact of screening for Down's syndrome on the prevalence of live births and antenatal diagnoses of Edwards and Patau syndrome. England and Wales, 2005 to 2012. Data from the National Down Syndrome Cytogenetic Register, which contains information on nearly all ante- or postnatally diagnosed cases of Edwards or Patau syndrome in which a karyotype was confirmed, were analysed. From 2005 to 2012, 3,941 diagnoses of Edwards syndrome and 1,567 diagnoses of Patau syndrome were recorded (prevalence of 7.0 and 2.8 per 10,000 births respectively). Only 11% (95% confidence interval [CI]: 10-12) of diagnoses of Edwards syndrome and 13% (95% CI: 11-14) of Patau syndrome were live births, resulting in live birth prevalences of 0.8 (95% CI: 0.7-0.8) and 0.4 (95% CI: 0.3-0.4) per 10,000 live births respectively. About 90% of pregnancies with Edwards or Patau syndrome were diagnosed antenatally, and this proportion remained constant over time. The proportion of diagnoses detected before 15 weeks increased from 50% in 2005 to 53% in 2012 for Edwards syndrome, and from 41% in 2005 to 63% in 2012 for Patau syndrome. Almost 700 women per year had a pregnancy with Edwards or Patau syndrome. Over 90% of these pregnancies were detected antenatally, with the increased use of first trimester screening for Down's syndrome resulting in the reduction in the mean gestational age at diagnosis of these syndromes. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  9. Quickly Removable Valve

    NASA Technical Reports Server (NTRS)

    Robbins, John S.

    1988-01-01

    Unit removed with minimal disturbance. Valve inlet and outlet ports adjacent to each other on same side of valve body. Ports inserted into special manifold on fluid line. Valve body attached to manifold by four bolts or, alternatively, by toggle clamps. Electromechanical actuator moves in direction parallel to fluid line to open and close valve. When necessary to clean valve, removed simply by opening bolts or toggle clamps. No need to move or separate ports of fluid line. Valve useful where disturbance of fluid line detrimental or where fast maintenance essential - in oil and chemical industries, automotive vehicles, aircraft, and powerplants.

  10. Bellows sealed plug valve

    DOEpatents

    Dukas, Jr., Stephen J.

    1990-01-01

    A bellows sealed plug valve includes a valve body having an inlet passage and an outlet passage, a valve chamber between the inlet and outlet passages. A valve plug has substantially the same shape as the valve chamber and is rotatably disposed therein. A shaft is movable linearly in response to a signal from a valve actuator. A bellows is sealingly disposed between the valve chamber and the valve actuator and means are located between the bellows and the valve plug for converting linear movement of the shaft connected to the valve actuator to rotational movement of the plug. Various means are disclosed including helical thread mechanism, clevis mechanism and rack and pinion mechanism, all for converting linear motion to rotational motion.

  11. Check valve installation in pilot operated relief valve prevents reverse pressurization

    NASA Technical Reports Server (NTRS)

    Oswalt, L.

    1966-01-01

    Two check valves prevent reverse flow through pilot-operated relief valves of differential area piston design. Title valves control pressure flow to ensure that the piston dome pressure is always at least as great as the main relief valve discharge pressure.

  12. Radiographic findings of post-operative double stapled trans anal rectal resection (STARR) in patient with obstructed defecation syndrome (ODS).

    PubMed

    Grassi, Roberto; Romano, Stefania; Micera, Osvaldo; Fioroni, Claudio; Boller, Brigitta

    2005-03-01

    Longo's procedure of double stapled trans anal rectal resection (STARR) has been evocated as surgical treatment of the obstructed defecation syndrome (ODS) in patients with rectal mucosal prolapse. The aim of this study was to investigate the post-interventional findings of this technique, to help radiologist in knowledge of the changed morphology of the rectal lumen, also in attempt to recognize some potential related complications.

  13. Device landing zone calcification and its impact on residual regurgitation after transcatheter aortic valve implantation with different devices.

    PubMed

    Seiffert, Moritz; Fujita, Buntaro; Avanesov, Maxim; Lunau, Clemens; Schön, Gerhard; Conradi, Lenard; Prashovikj, Emir; Scholtz, Smita; Börgermann, Jochen; Scholtz, Werner; Schäfer, Ulrich; Lund, Gunnar; Ensminger, Stephan; Treede, Hendrik

    2016-05-01

    Calcification of the device landing zone is linked to paravalvular regurgitation after transcatheter aortic valve implantation (TAVI). The mechanisms remain incompletely understood and the performance of next-generation transcatheter heart valves (THV) has not been investigated. We evaluated the impact of calcification patterns on residual aortic regurgitation (AR) after TAVI with different THV in patients with severe aortic stenosis. TAVI was performed in 537 patients at two centres. Devices implanted were the Edwards Sapien XT (n = 254), Medtronic CoreValve (n = 123), JenaValve (n = 62), Medtronic Engager (n = 56), and Symetis Acurate (n = 42) prostheses. Calcification of the device landing zone was retrospectively assessed from contrast-enhanced multidetector computed tomography data and correlated with echocardiographic and clinical data. Calcium volumes of the aortic valve and left-ventricular outflow tract were associated with residual AR: No AR, 604 mm(3) (inter-quartile range, IQR 349-916); trace AR, 639 mm(3) (IQR 368-948); mild AR, 710 mm(3) (IQR 412-2078); ≥moderate AR, 1041 mm(3) (IQR 791-1417, P = 0.001). Device landing zone calcium, particularly if located in the left-ventricular outflow tract, and a low cover index were predictive of AR. Differences in the incidence of AR were observed with regard to THV type. Higher calcium volume was associated with the need for post-dilation (n = 134, median 852 [IQR 342-945] vs. 604 [IQR 542-1207] mm(3), P < 0.001). Calcification of the device landing zone, particularly if located inferior to the annulus, was independently associated with residual AR after TAVI with all evaluated THV; however, the incidence of paravalvular leakage differed significantly between the devices implanted. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  14. Acting Administrator Lightfoot Visits Ball Aerospace

    NASA Image and Video Library

    2017-04-06

    Acting NASA Administrator Robert Lightfoot, left, views a clean room with Tim Schoenweis, senior project engineer for the Ozone Mapping Profiler Suite (OMPS) at Ball Aerospace, right, Thursday, April 6, 2017 at Ball Aerospace in Boulder, Colo. Photo Credit: (NASA/Joel Kowsky)

  15. Acting Administrator Lightfoot Visits Ball Aerospace

    NASA Image and Video Library

    2017-04-06

    Acting NASA Deputy Administrator Lesa Roe, center, views a clean room with Tim Schoenweis, senior project engineer for the Ozone Mapping Profiler Suite (OMPS) at Ball Aerospace, left, Thursday, April 6, 2017 at Ball Aerospace in Boulder, Colo. Photo Credit: (NASA/Joel Kowsky)

  16. How Magnus Bends the Flying Ball--Experimenting and Modeling

    ERIC Educational Resources Information Center

    Timková, V.; Ješková, Z.

    2017-01-01

    Students are well aware of the effect of the deflection of sports balls when they have been given a spin. A volleyball, tennis, or table tennis ball served with topspin results in an additional downward force that makes the ball difficult to catch and return. In soccer, the effect of sidespin causes the ball to curve unexpectedly sideways,…

  17. Mucormycosis (Mucor fungus ball) of the maxillary sinus.

    PubMed

    Cho, Hang Sun; Yang, Hoon Shik; Kim, Kyung Soo

    2014-01-01

    A fungus ball is an extramucosal fungal proliferation that completely fills one or more paranasal sinuses and usually occurs as a unilateral infection. It is mainly caused by Aspergillus spp in an immunocompetent host, but some cases of paranasal fungal balls reportedly have been caused by Mucor spp. A Mucor fungus ball is usually found in the maxillary sinus and/or the sphenoid sinus and may be black in color. Patients with mucormycosis, or a Mucor fungal ball infection, usually present with facial pain or headache. On computed tomography, there are no pathognomonic findings that are conclusive for a diagnosis of mucormycosis. In this article we report a case of mucormycosis in a 56-year-old woman and provide a comprehensive review of the literature on the "Mucor fungus ball." To the best of our knowledge, 5 case reports (8 patients) have been published in which the fungus ball was thought to be caused by Mucor spp.

  18. The strange flight behaviour of slowly spinning soccer balls

    NASA Astrophysics Data System (ADS)

    Mizota, Taketo; Kurogi, Kouhei; Ohya, Yuji; Okajima, Atsushi; Naruo, Takeshi; Kawamura, Yoshiyuki

    2013-05-01

    The strange three-dimensional flight behaviour of slowly spinning soccer balls is one of the most interesting and unknown phenomenon associated with the trajectories of sports balls. Many spectators have experienced numerous exciting and emotional instances while observing the curious flight behaviour of these balls. We examine the aerodynamic mechanisms of erratic ball behaviours through real flight observations, unsteady force measurements and flow pattern visualisations. The strange behaviour is elucidated by the relationship between the unsteady forces on the ball and the wake flow. The irregular changes in position for twin longitudinal vortices have already been discovered in the supercritical Reynolds number region of a sphere with a smooth surface. This finding is applicable to the strange behaviour of the flight of soccer balls with this supercritical flow. The players, spectators, and television viewers will gain greater insight into the effects of soccer ball flights.

  19. Aerodynamics in the classroom and at the ball park

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2012-04-01

    Experiments suitable for classroom projects or demonstrations are described concerning the aerodynamics of polystyrene balls. A light ball with sufficient backspin can curve vertically upward through the air, defying gravity and providing a dramatic visual demonstration of the Magnus effect. A ball projected with backspin can also curve downward with a vertical acceleration greater than that due to gravity if the Magnus force is negative. These effects were investigated by filming the flight of balls projected in an approximately horizontal direction so that the lift and drag forces could be easily measured. The balls were also fitted with artificial raised seams and projected with backspin toward a vertical target in order to measure the sideways deflection over a known horizontal distance. It was found that (a) a ball with a seam on one side can deflect either left or right depending on its launch speed and (b) a ball with a baseball seam can also deflect sideways even when there is no sideways component of the drag or lift forces acting on the ball. Depending on the orientations of the seam and the spin axis, a sideways force on a baseball can arise either if there is rough patch on one side of the ball or if there is a smooth patch. A scuff ball with a rough patch on one side is illegal in baseball. The effect of a smooth patch is a surprising new observation.

  20. Effect of soccer shoe upper on ball behaviour in curve kicks

    PubMed Central

    Ishii, Hideyuki; Sakurai, Yoshihisa; Maruyama, Takeo

    2014-01-01

    New soccer shoes have been developed by considering various concepts related to kicking, such as curving a soccer ball. However, the effects of shoes on ball behaviour remain unclear. In this study, by using a finite element simulation, we investigated the factors that affect ball behaviour immediately after impact in a curve kick. Five experienced male university soccer players performed one curve kick. We developed a finite element model of the foot and ball and evaluated the validity of the model by comparing the finite element results for the ball behaviour immediately after impact with the experimental results. The launch angle, ball velocity, and ball rotation in the finite element analysis were all in general agreement with the experimental results. Using the validated finite element model, we simulated the ball behaviour. The simulation results indicated that the larger the foot velocity immediately before impact, the larger the ball velocity and ball rotation. Furthermore, the Young's modulus of the shoe upper and the coefficient of friction between the shoe upper and the ball had little effect on the launch angle, ball velocity, and ball rotation. The results of this study suggest that the shoe upper does not significantly influence ball behaviour. PMID:25266788

  1. Effect of soccer shoe upper on ball behaviour in curve kicks

    NASA Astrophysics Data System (ADS)

    Ishii, Hideyuki; Sakurai, Yoshihisa; Maruyama, Takeo

    2014-08-01

    New soccer shoes have been developed by considering various concepts related to kicking, such as curving a soccer ball. However, the effects of shoes on ball behaviour remain unclear. In this study, by using a finite element simulation, we investigated the factors that affect ball behaviour immediately after impact in a curve kick. Five experienced male university soccer players performed one curve kick. We developed a finite element model of the foot and ball and evaluated the validity of the model by comparing the finite element results for the ball behaviour immediately after impact with the experimental results. The launch angle, ball velocity, and ball rotation in the finite element analysis were all in general agreement with the experimental results. Using the validated finite element model, we simulated the ball behaviour. The simulation results indicated that the larger the foot velocity immediately before impact, the larger the ball velocity and ball rotation. Furthermore, the Young's modulus of the shoe upper and the coefficient of friction between the shoe upper and the ball had little effect on the launch angle, ball velocity, and ball rotation. The results of this study suggest that the shoe upper does not significantly influence ball behaviour.

  2. Globe stability during simulated vitrectomy with valved and non-valved trocar cannulas

    PubMed Central

    Abulon, Dina Joy; Charles, Martin; Charles, Daniel E

    2015-01-01

    Purpose To compare the effects of valved and non-valved cannulas on intraocular pressure (IOP), fluid leakage, and vitreous incarceration during simulated vitrectomy. Methods Three-port pars plana incisions were generated in six rubber eyes using 23-, 25-, and 27-gauge valved and non-valved trocar cannulas. The models were filled with air and IOP was measured. Similar procedures were followed for 36 acrylic eyes filled with saline solution. Vitreous incarceration was analyzed in eleven rabbit and twelve porcine cadaver eyes. Results In the air-filled model, IOP loss was 89%–94% when two non-valved cannulas were unoccupied versus 1%–5% when two valved cannulas were unoccupied. In the fluid-filled model, with non-valved cannulas, IOP dropped while fluid leaked from the open ports. With two open ports, the IOP dropped to 20%–30% of set infusion pressure, regardless of infusion pressure and IOP compensation. The IOP was maintained in valved cannulas when one or two ports were left open, regardless of IOP compensation settings. There was no or minimal fluid leakage through open ports at any infusion pressure. Direct microscopic analysis of rabbit eyes showed that vitreous incarceration was significantly greater with 23-gauge non-valved than valved cannulas (P<0.005), and endoscopy of porcine eyes showed that vitreous incarceration was significantly greater with 23-gauge (P<0.05) and 27-gauge (P<0.05) non-valved cannulas. External observation of rabbit eyes showed vitreous prolapse through non-valved, but not valved, cannulas. Conclusion Valved cannulas surpassed non-valved cannulas in maintaining IOP, preventing fluid leakage, and reducing vitreous incarceration during simulated vitrectomy. PMID:26445520

  3. Microfluidic sieve valves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Quake, Stephen R; Marcus, Joshua S; Hansen, Carl L

    2015-01-13

    Sieve valves for use in microfluidic device are provided. The valves are useful for impeding the flow of particles, such as chromatography beads or cells, in a microfluidic channel while allowing liquid solution to pass through the valve. The valves find particular use in making microfluidic chromatography modules.

  4. Friction torque in thrust ball bearings grease lubricated

    NASA Astrophysics Data System (ADS)

    Ianuş, G.; Dumitraşcu, A. C.; Cârlescu, V.; Olaru, D. N.

    2016-08-01

    The authors investigated experimentally and theoretically the friction torque in a modified thrust ball bearing having only 3 balls operating at low axial load and lubricated with NGLI-00 and NGLI-2 greases. The experiments were made by using spin-down methodology and the results were compared with the theoretical values based on Biboulet&Houpert's rolling friction equations. Also, the results were compared with the theoretical values obtained with SKF friction model adapted for 3 balls. A very good correlation between experiments and Biboulet_&_Houpert's predicted results was obtained for the two greases. Also was observed that the theoretical values for the friction torque calculated with SKF model adapted for a thrust ball bearing having only 3 balls are smaller that the experimental values.

  5. Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results

    NASA Astrophysics Data System (ADS)

    Vereš, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; Chastel, Serge; Wainscoat, Richard J.; Burgett, William S.; Chambers, Kenneth C.; Flewelling, Heather; Kaiser, Nick; Magnier, Eugen A.; Morgan, Jeff S.; Price, Paul A.; Tonry, John L.; Waters, Christopher

    2015-11-01

    We present the results of a Monte Carlo technique to calculate the absolute magnitudes (H) and slope parameters (G) of ∼240,000 asteroids observed by the Pan-STARRS1 telescope during the first 15 months of its 3-year all-sky survey mission. The system's exquisite photometry with photometric errors ≲ 0.04mag , and well-defined filter and photometric system, allowed us to derive accurate H and G even with a limited number of observations and restricted range in phase angles. Our Monte Carlo method simulates each asteroid's rotation period, amplitude and color to derive the most-likely H and G, but its major advantage is in estimating realistic statistical + systematic uncertainties and errors on each parameter. The method was tested by comparison with the well-established and accurate results for about 500 asteroids provided by Pravec et al. (Pravec, P. et al. [2012]. Icarus 221, 365-387) and then applied to determining H and G for the Pan-STARRS1 asteroids using both the Muinonen et al. (Muinonen, K. et al. [2010]. Icarus 209, 542-555) and Bowell et al. (Bowell, E. et al. [1989]. Asteroids III, Chapter Application of Photometric Models to Asteroids. University of Arizona Press, pp. 524-555) phase functions. Our results confirm the bias in MPC photometry discovered by Jurić et al. (Jurić, M. et al. [2002]. Astrophys. J. 124, 1776-1787).

  6. Landing, Edwards AFB, CA

    NASA Image and Video Library

    1983-04-09

    STS006-46-667 (9 April 1983) --- One of the final pictures taken aboard the space shuttle Challenger is this 35mm frame of Landing Strip 22 at Edwards Air Force Base as the reusable spacecraft was lined up for its landing only seconds later. The frame was exposed by astronaut Donald H. Peterson, STS-6 mission specialist, who was stretching behind the commander’s seat occupied by astronaut Paul J. Weitz on the flight deck. Also onboard the spacecraft for the five-day flight were astronauts Karol J. Bobko, pilot, and Dr. F. Story Musgrave, mission specialist. Photo credit: NASA

  7. Sequential transcatheter aortic valve implantation due to valve dislodgement - a Portico valve implanted over a CoreValve bioprosthesis.

    PubMed

    Campante Teles, Rui; Costa, Cátia; Almeida, Manuel; Brito, João; Sondergaard, Lars; Neves, José P; Abecasis, João; M Gabriel, Henrique

    2017-03-01

    Transcatheter aortic valve implantation (TAVI) has become an important treatment in high surgical risk patients with severe aortic stenosis (AS), whose complications need to be managed promptly. The authors report the case of an 86-year-old woman presenting with severe symptomatic AS, rejected for surgery due to advanced age and comorbidities. The patient underwent a first TAVI, with implantation of a Medtronic CoreValve ® , which became dislodged and migrated to the ascending aorta. Due to the previous balloon valvuloplasty, the patient's AS became moderate, and her symptoms improved. After several months, she required another intervention, performed with a St. Jude Portico ® repositionable self-expanding transcatheter aortic valve. There was a good clinical response that was maintained at one-year follow-up. The use of a self-expanding transcatheter bioprosthesis with repositioning features is a solution in cases of valve dislocation to avoid suboptimal positioning of a second implant, especially when the two valves have to be positioned overlapping or partially overlapping each other. Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. Compliance through pollution prevention opportunity assessments at Edwards AFB -- Development, results and lessons learned

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beutelman, H.P.; Lawrence, A.

    1999-07-01

    Edwards Air Force Base (AFB), located in the Mojave Desert of southern California, is required to comply with environmental requirements for air pollution emissions, hazardous waste disposal, and clean water. The resources required to meet these many compliance requirements represents an ever increasing financial burden to the base, and to the Department of Defense. A recognized superior approach to environmental management is to achieve compliance through a proactive pollution prevention (P2) program which mitigates, and when possible, eliminates compliance requirements and costs, while at the same time reducing pollution released to the environment. At Edwards AFB, the Environmental Management Officemore » P2 Branch developed and implemented a strategy that addresses this concept, better known as Compliance Through Pollution Prevention (CTP2). At the 91st AWMA Annual Meeting and Exhibition, Edwards AFB presented a paper on its strategy and implementation of its CTP2 concept. Part of that strategy and implementation included accomplishment of process specific focused P2 opportunity assessments (OAs). Starting in 1998, Edwards AFB initiated a CTP2 OA project where OAs were targeted on those operational processes, identified as compliance sites, that contributed most to the compliance requirements and costs at Edwards AFB. The targeting of these compliance sites was accomplished by developing a compliance matrix that prioritized processes in accordance with an operational risk management approach. The Edwards AFB CTP2 PPOA project is the first of its kind within the Air Force Material Command, and is serving as a benchmark for establishment of the CTP2 OA process.« less

  9. Problem: Heart Valve Stenosis

    MedlinePlus

    ... valve . Learn about the different types of stenosis: Aortic stenosis Tricuspid stenosis Pulmonary stenosis Mitral stenosis Outlook for ... Disease "Innocent" Heart Murmur Problem: Valve Stenosis - Problem: Aortic Valve Stenosis - Problem: Mitral Valve Stenosis - Problem: Tricuspid Valve Stenosis - ...

  10. Laser Sintering Technology and Balling Phenomenon.

    PubMed

    Oyar, Perihan

    2018-02-01

    The aim of this review was to evaluate the balling phenomenon which occurs typically in Selective Laser Sintering (SLS). The balling phenomenon is a typical SLS defect, and observed in laser sintered powder, significantly reduces the quality of SLS, and hinders the further development of SLS Technology. Electronic database searches were performed using Google Scholar. The keywords "laser sintering, selective laser sintering, direct metal laser melting, and balling phenomenon" were searched in title/abstract of publications, limited to December 31, 2016. The inclusion criteria were SLS, balling phenomenon, some alloys (such as Cr-Co, iron, stainless steel, and Cu-based alloys) mechanical properties, microstructure and bond strength between metal-ceramic crown, laboratory studies, full text, and in English language. A total of 100 articles were found the initial search and yielded a total of 50 studies, 30 of which did not fulfill the inclusion criteria and were therefore excluded. In addition, 20 studies were found by screening the reference list of all included publications. Finally, 40 studies were selected for this review. The method in question is regulated by powder material characteristics and the conditions of laser processing. The procedure of formation, affecting factors, and the mechanism of the balling effect are very complex.

  11. Silicon ball grid array chip carrier

    DOEpatents

    Palmer, David W.; Gassman, Richard A.; Chu, Dahwey

    2000-01-01

    A ball-grid-array integrated circuit (IC) chip carrier formed from a silicon substrate is disclosed. The silicon ball-grid-array chip carrier is of particular use with ICs having peripheral bond pads which can be reconfigured to a ball-grid-array. The use of a semiconductor substrate such as silicon for forming the ball-grid-array chip carrier allows the chip carrier to be fabricated on an IC process line with, at least in part, standard IC processes. Additionally, the silicon chip carrier can include components such as transistors, resistors, capacitors, inductors and sensors to form a "smart" chip carrier which can provide added functionality and testability to one or more ICs mounted on the chip carrier. Types of functionality that can be provided on the "smart" chip carrier include boundary-scan cells, built-in test structures, signal conditioning circuitry, power conditioning circuitry, and a reconfiguration capability. The "smart" chip carrier can also be used to form specialized or application-specific ICs (ASICs) from conventional ICs. Types of sensors that can be included on the silicon ball-grid-array chip carrier include temperature sensors, pressure sensors, stress sensors, inertia or acceleration sensors, and/or chemical sensors. These sensors can be fabricated by IC processes and can include microelectromechanical (MEM) devices.

  12. Modified Ball and Socket Coupling

    DOEpatents

    Conley, Jr, W. R.; Pitman, R. W.

    1961-05-23

    A ball and socket coupling arrangement is given in which the male and female members may be engaged or disengaged without visual aid. The female member has an internal spherical seat through which slots are provided to accommodate appropriately arranged and shaped ribs in the male ball member. After engagement of the members, one or both are rotated to lock them together to prevent accidental disengagement.

  13. MODIFIED BALL AND SOCKET COUPLING

    DOEpatents

    Kalen, D.D.

    1961-05-23

    A ball and socket coupling arrangement is described in which the male and female members may be engaged or disengaged without visual aid. The female member has an internal spherical seat through which slots are provided to accommodate appropriately arranged and shaped ribs in the ball member. After engagement of the members, one or both are rotated to lock them together to prevent accidental disengagement. (AEC)

  14. Chronic back pain and associated work and non-work variables among farmworkers from Starr County, Texas.

    PubMed

    Shipp, Eva M; Cooper, Sharon P; del Junco, Deborah J; Delclos, George L; Burau, Keith D; Tortolero, Susan; Whitworth, Ryan E

    2009-01-01

    This study estimated the prevalence of chronic back pain among migrant farmworker family members and identified associated work and non-work variables. Migrant farmworkers (n = 390 from 267 families) from Starr County, Texas were interviewed in their home once a year for 2 years. The original survey included items measuring demographics, smoking, sleep, farm work, and chronic back pain. For this cross-sectional analysis, multi-level logistic regression was used to identify associated work and other variables associated with chronic back pain while accounting for intraclass correlations due to repeated measures and multiple family members. The prevalence of chronic back pain during the last migration season ranged from 9.5% among the youngest children to 33.3% among mothers. Variables significantly associated with chronic back pain were age (odds ratio [OR], 1.03, per year increase), depressive symptoms while migrating (OR, 8.72), fewer than 8 hours of sleep at home in Starr County (OR, 2.26), fairly bad/very bad quality of sleep while migrating (OR, 3.25), sorting crops at work (OR, 0.18), and working tree crops (OR, 11.72). The role of work exposures, depressive symptoms, and sleep in chronic back pain among farmworkers warrants further examination. Refinements in outcome and exposure assessments are also needed given the lack of a standardized case definition and the variety of tasks and crops involved in farm work in the United States.

  15. Vacuum breaker valve assembly

    DOEpatents

    Thompson, J.L.; Upton, H.A.

    1999-04-27

    Breaker valve assemblies for a simplified boiling water nuclear reactor are described. The breaker valve assembly, in one form, includes a valve body and a breaker valve. The valve body includes an interior chamber, and an inlet passage extends from the chamber and through an inlet opening to facilitate transporting particles from outside of the valve body to the interior chamber. The breaker valve is positioned in the chamber and is configured to substantially seal the inlet opening. Particularly, the breaker valve includes a disk which is sized to cover the inlet opening. The disk is movably coupled to the valve body and is configured to move substantially concentrically with respect to the valve opening between a first position, where the disk completely covers the inlet opening, and a second position, where the disk does not completely cover the inlet opening. 1 fig.

  16. Vacuum breaker valve assembly

    DOEpatents

    Thompson, Jeffrey L.; Upton, Hubert Allen

    1999-04-27

    Breaker valve assemblies for a simplified boiling water nuclear reactor are described. The breaker valve assembly, in one form, includes a valve body and a breaker valve. The valve body includes an interior chamber, and an inlet passage extends from the chamber and through an inlet opening to facilitate transporting particles from outside of the valve body to the interior chamber. The breaker valve is positioned in the chamber and is configured to substantially seal the inlet opening. Particularly, the breaker valve includes a disk which is sized to cover the inlet opening. The disk is movably coupled to the valve body and is configured to move substantially concentrically with respect to the valve opening between a first position, where the disk completely covers the inlet opening, and a second position, where the disk does not completely cover the inlet opening.

  17. The effects of ball size distribution on attritor efficiency

    NASA Astrophysics Data System (ADS)

    Cook, T. M.; Courtney, T. H.

    1995-09-01

    A study was undertaken to determine how media dynamics are altered when differently sized grinding balls are used in an attritor. Cinematographic techniques identify the extent of segregation/mixing of the differently sized balls within the attritor as a function of impeller rotational velocity and small ball number fraction. This permits determination of rotational velocities needed to most efficiently use the tactic of milling with differently sized media. Cinematographic observations show that the close-packed media array, assumed when balls of the same size are used for milling, is disrupted when differently sized balls are used. Monitoring powder particle numbers as a function of milling time for the situations when the same and differently sized balls are used can be used to assess relative milling efficiencies. Results indicate powder deformation, fracture, and welding are enhanced through employment of differently sized balls. This conclusion is reinforced by observations of microstructural characteristics of powder processed with the different type of media.

  18. Wide cool and ultracool companions to nearby stars from Pan-STARRS 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deacon, Niall R.; Liu, Michael C.; Magnier, Eugene A.

    2014-09-10

    We present the discovery of 57 wide (>5'') separation, low-mass (stellar and substellar) companions to stars in the solar neighborhood identified from Pan-STARRS 1 (PS1) data and the spectral classification of 31 previously known companions. Our companions represent a selective subsample of promising candidates and span a range in spectral type of K7-L9 with the addition of one DA white dwarf. These were identified primarily from a dedicated common proper motion search around nearby stars, along with a few as serendipitous discoveries from our Pan-STARRS 1 brown dwarf search. Our discoveries include 23 new L dwarf companions and one knownmore » L dwarf not previously identified as a companion. The primary stars around which we searched for companions come from a list of bright stars with well-measured parallaxes and large proper motions from the Hipparcos catalog (8583 stars, mostly A-K dwarfs) and fainter stars from other proper motion catalogs (79170 stars, mostly M dwarfs). We examine the likelihood that our companions are chance alignments between unrelated stars and conclude that this is unlikely for the majority of the objects that we have followed-up spectroscopically. We also examine the entire population of ultracool (>M7) dwarf companions and conclude that while some are loosely bound, most are unlikely to be disrupted over the course of ∼10 Gyr. Our search increases the number of ultracool M dwarf companions wider than 300 AU by 88% and increases the number of L dwarf companions in the same separation range by 82%. Finally, we resolve our new L dwarf companion to HIP 6407 into a tight (0.''13, 7.4 AU) L1+T3 binary, making the system a hierarchical triple. Our search for these key benchmarks against which brown dwarf and exoplanet atmosphere models are tested has yielded the largest number of discoveries to date.« less

  19. A not-so-funny thing happened on the way to relicensing the Edwards Dam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ayer, F.J.; Isaacson, M.

    1995-12-31

    What started out as a seemingly straightforward and simple exercise, obtaining a new FERC license for the Edwards Dam in Augusta, Maine, turned out to be anything but straightforward and far from simple. This article tells the story of one of the more interesting and possibly precedent setting cases in the {open_quotes}class of 93{close_quotes} and is presented in three sections: (1) the history of the Edwards Dam and the FERC regulatory process through the spring of 1995; (2) Edwards` response to the dam removal campaign; and (3) recommendations for FERC licensees threatened by dam removal during relicensing.

  20. Zero-leak valve

    NASA Technical Reports Server (NTRS)

    Macglashan, W. F., Jr.

    1980-01-01

    Zero-leakage valve has fluid-sealing diaphragm support and flat sievelike sealing surface. Diaphragm-support valve is easy to fabricate and requires minimum maintenance. Potential applications include isolation valve for waste systems and remote air-actuated valve. Device is also useful in controlling flow of liquid fluorine and corrosive fluids at high pressures.

  1. Redo aortic valve surgery versus transcatheter valve-in-valve implantation for failing surgical bioprosthetic valves: consecutive patients in a single-center setting

    PubMed Central

    Wottke, Michael; Deutsch, Marcus-André; Krane, Markus; Piazza, Nicolo; Lange, Ruediger; Bleiziffer, Sabine

    2015-01-01

    Background Due to a considerable rise in bioprosthetic as opposed to mechanical valve implantations, an increase of patients presenting with failing bioprosthetic surgical valves in need of a reoperation is to be expected. Redo surgery may pose a high-risk procedure. Transcatheter aortic valve-in-valve implantation is an innovative, less-invasive treatment alternative for these patients. However, a comprehensive evaluation of the outcome of consecutive patients after a valve-in-valve TAVI [transcatheter aortic valve-in-surgical aortic valve (TAV-in-SAV)] as compared to a standard reoperation [surgical aortic valve redo-operation (SAV-in-SAV)] has not yet been performed. The goal of this study was to compare postoperative outcomes after TAV-in-SAV and SAV-in-SAV in a single center setting. Methods All SAV-in-SAV and TAV-in-SAV patients from January 2001 to October 2014 were retrospectively reviewed. Patients with previous mechanical or transcatheter valves, active endocarditis and concomitant cardiac procedures were excluded. Patient characteristics, preoperative data, post-procedural complications, and 30-day mortality were collected from a designated database. Mean values ± SD were calculated for all continuous variables. Counts and percentages were calculated for categorical variables. The Chi-square and Fisher exact tests were used to compare categorical variables. Continuous variables were compared using the t-test for independent samples. A 2-sided P value <0.05 was considered statistically significant. Results A total of 102 patients fulfilled the inclusion criteria, 50 patients (49%) underwent a transcatheter valve-in-valve procedure, while 52 patients (51%) underwent redo-surgery. Patients in the TAV-in-SAV group were significantly older, had a higher mean logistic EuroSCORE and exhibited a lower mean left ventricular ejection fraction than patients in the SAV-in-SAV group (78.1±6.7 vs. 66.2±13.1, P<0.001; 27.4±18.7 vs. 14.4±10, P<0.001; and 49.8±13

  2. Two Balls' Collision of Mass Ratio 3:1

    NASA Astrophysics Data System (ADS)

    Ogawara, Yasuo; Hull, Michael M.

    2018-04-01

    Students will sometimes ask why momentum and kinetic energy concepts are both necessary. When physics teachers demonstrate situations that require both an understanding of kinetic energy and momentum, a favorite is Newton's cradle, or a comparable demonstration of two balls of equal mass hitting each other. However, in addition to the case of two balls of equal mass, if a ball hits another ball of three times the mass with equal speed, the results are also interesting, and, like the equal-mass demonstration, both kinetic energy and momentum are critical for understanding the motion.

  3. Dynamics of a bouncing ball

    NASA Astrophysics Data System (ADS)

    Chastaing, J.-Y.; Bertin, E.; Géminard, J.-C.

    2015-06-01

    We describe an experiment dedicated to the study of the trajectories of a ball bouncing on a vibrating plate. Using an experimental device of our own design, it is possible to impose arbitrary trajectories on the plate and we show that the entire trajectory of the ball can be reconstructed solely from measurement of the times the ball hits the plate. In this paper, we make use of our apparatus to introduce the notion of dissipative collisions and to propose three different ways to measure the associated restitution coefficient. We then report on correlations in the chaotic regime and theoretically discuss the complex patterns that are exhibited in the case of a sinusoidal vibration. Lastly, we show that the use of an aperiodic driving vibration makes it possible to minimize part of these correlations.

  4. Rotary pneumatic valve

    DOEpatents

    Hardee, Harry C.

    1991-01-01

    A rotary pneumatic valve which is thrust balanced and the pneumatic pressure developed produces only radial loads on the valve cylinder producing negligible resistance and thus minimal torque on the bearings of the valve. The valve is multiplexed such that at least two complete switching cycles occur for each revolution of the cylinder spindle.

  5. Overdrainage and shunt technology. A critical comparison of programmable, hydrostatic and variable-resistance valves and flow-reducing devices.

    PubMed

    Aschoff, A; Kremer, P; Benesch, C; Fruh, K; Klank, A; Kunze, S

    1995-04-01

    When vertical body position is simulated, conventional differential pressure valves show an absolutely unphysiological flow, which is 2-170 times the normal liquor production rate. Although this is compensated in part by the resistance of the silicon tubes, which may produce up to 94% of the resistance of the complete shunt system, a negative intracranial pressure (ICP) of up to 30-44 cmH2O is an unavoidable consequence, which can be followed by subdural hematomas, slit ventricles, and other well-known complications. Modern shunt technology offers programmable, hydrostatic, and "flow-controlled" valves and anti-siphon devices; we have tested 13 different designs from 7 manufacturers (56 specimens), using the "Heidelberg Valve Test Inventory" with 16 subtests. "Programmable" valves reduce, but cannot exclude, unphysiological flow rates: even in the highest position and in combination with a standard catheter typical programmable Medos-Hakim valves allow a flow of 93-232 ml/h, Sophy SU-8-valves 86-168 ml/h with 30 cmH2O. The effect of hydrostatic valves (Hakim-Lumbar, Chhabra) can be inactivated by movements of daily life. The weight of the metal balls in most valves was too low for adequate flow reduction. Antisiphon devices are highly dependent on external, i.e. subcutaneous, pressure which has unpredictable influences on shunt function, and clinically is sometimes followed by shunt insufficiency. Two new Orbis-Sigma valves showed relatively physiological flow rates even when the vertical position (30 cmH2O) was simulated. One showed an insufficient flow (5.7 ml/h), and one was primarily obstructed. These have by far the smallest outlet of all valves. Additionally, the ruby pin tends to stick. Therefore, a high susceptibility to obliterations and blockade is unavoidable. Encouraging results obtained in pediatric patients contrast with disappointing experiences in some German and Swedish hospitals, which suggests that our laboratory findings are confirmed by

  6. STS-58 Landing at Edwards with Drag Chute

    NASA Image and Video Library

    1993-11-01

    A drag chute slows the space shuttle Columbia as it rolls to a perfect landing concluding NASA's longest mission at that time, STS-58, at the Ames-Dryden Flight Research Facility (later redesignated the Dryden Flight Research Center), Edwards, California, with a 8:06 a.m. (PST) touchdown 1 November 1993 on Edward's concrete runway 22. The planned 14 day mission, which began with a launch from Kennedy Space Center, Florida, at 7:53 a.m. (PDT), October 18, was the second spacelab flight dedicated to life sciences research. Seven Columbia crewmembers performed a series of experiments to gain more knowledge on how the human body adapts to the weightless environment of space. Crewmembers on this flight included: John Blaha, commander; Rick Searfoss, pilot; payload commander Rhea Seddon; mission specialists Bill MacArthur, David Wolf, and Shannon Lucid; and payload specialist Martin Fettman.

  7. Scissor thrust valve actuator

    DOEpatents

    DeWall, Kevin G.; Watkins, John C; Nitzel, Michael E.

    2006-08-29

    Apparatus for actuating a valve includes a support frame and at least one valve driving linkage arm, one end of which is rotatably connected to a valve stem of the valve and the other end of which is rotatably connected to a screw block. A motor connected to the frame is operatively connected to a motor driven shaft which is in threaded screw driving relationship with the screw block. The motor rotates the motor driven shaft which drives translational movement of the screw block which drives rotatable movement of the valve driving linkage arm which drives translational movement of the valve stem. The valve actuator may further include a sensory control element disposed in operative relationship with the valve stem, the sensory control element being adapted to provide control over the position of the valve stem by at least sensing the travel and/or position of the valve stem.

  8. Services for Children with Special Needs in Prince Edward Island over the Last Decade.

    ERIC Educational Resources Information Center

    Timmons, Vianne

    2001-01-01

    This article describes legislative and policy provisions that support educational services for children with disabilities in Prince Edward Island. It begins with some general information on Prince Edward Island and then explores recent teacher education and inclusion initiatives that have affected the service delivery for children with…

  9. Recellularization of decellularized heart valves: Progress toward the tissue-engineered heart valve

    PubMed Central

    VeDepo, Mitchell C; Detamore, Michael S; Hopkins, Richard A; Converse, Gabriel L

    2017-01-01

    The tissue-engineered heart valve portends a new era in the field of valve replacement. Decellularized heart valves are of great interest as a scaffold for the tissue-engineered heart valve due to their naturally bioactive composition, clinical relevance as a stand-alone implant, and partial recellularization in vivo. However, a significant challenge remains in realizing the tissue-engineered heart valve: assuring consistent recellularization of the entire valve leaflets by phenotypically appropriate cells. Many creative strategies have pursued complete biological valve recellularization; however, identifying the optimal recellularization method, including in situ or in vitro recellularization and chemical and/or mechanical conditioning, has proven difficult. Furthermore, while many studies have focused on individual parameters for increasing valve interstitial recellularization, a general understanding of the interacting dynamics is likely necessary to achieve success. Therefore, the purpose of this review is to explore and compare the various processing strategies used for the decellularization and subsequent recellularization of tissue-engineered heart valves. PMID:28890780

  10. Detecting Wear In Ball Bearings During Operation

    NASA Technical Reports Server (NTRS)

    Hine, Michael J.

    1988-01-01

    Strain-gauge signals at harmonics of ball-bearing-cage frequencies signify wear. Brief report describes experiments in continuing effort to interpret vibrations of machinery in terms of wear in ball bearing.

  11. STS-92 - Landing at Edwards Air Force Base

    NASA Image and Video Library

    2000-10-24

    With its drag parachute deployed to help slow it down, the Space Shuttle Discovery rolls down the runway after landing at Edwards Air Force Base in Southern California at the conclusion of mission STS-92 on October 24, 2000.

  12. Edward Mills Purcell, August 30, 1912-March 7, 1997

    NASA Astrophysics Data System (ADS)

    Rigden, John S.

    2011-03-01

    I discuss the life, education, personality, and contributions of Edward Mills Purcell (1912-1997) to physics, radio astronomy, astrophysics, biological physics, physics teaching and education, and to the nation.

  13. A general theory for ball lightning structure and light output

    NASA Astrophysics Data System (ADS)

    Morrow, R.

    2018-03-01

    A general theory for free-floating ball lightning is presented which unifies the phantom plasma ball theory involving the production of very little light, with theories for ball lightning involving light output produced by burning particles from the soil. The mechanism for the formation of plasma balls is shown to be quite general, producing very similar plasma balls independent of initial ion densities over four orders of magnitude. All that is required is an excess of positive ions in the initial ball of ions. The central plasma density after 1 s is shown to be the reciprocal of the ion neutralization coefficient for all cases, both analytically and computationally. Further, the plasma region has zero electric field in all cases. Surrounding the plasma ball is a sphere of positive ions moving away from the centre via their own space-charge field; this space-charge field, which is the same in all cases near the plasma ball, drives negative ions and negative particles towards the plasma centre. The connection with burning particle theories is the proposition that the burning particles are highly-charged which is very likely after a lightning strike. Burning negatively charged particles would be driven into the plasma ball region and trapped while any positively charged particles would be driven away. The plasma ball structure is shown to last more than 10 s and the ‘burnout time’ for a typical coal particle (as an example) has been measured at 5-10 s this is comparable with the lifetimes observed for ball lightning. The light output from a few hundred particles is estimated to be ~1 W, a typical output for ball lightning. Finally, suggestions are made for the generation of ball lightning in the laboratory.

  14. Magnetically Operated Holding Plate And Ball-Lock Pin

    NASA Technical Reports Server (NTRS)

    Monford, Leo G., Jr.

    1992-01-01

    Magnetically operated holding plate and ball-locking-pin mechanism part of object attached to, or detached from second object. Mechanism includes tubular housing inserted in hole in second object. Plunger moves inside tube forcing balls to protrude from sides. Balls prevent tube from sliding out of second object. Simpler, less expensive than motorized latches; suitable for robotics applications.

  15. Measuring the Rebound Resilience of a Bouncing Ball

    ERIC Educational Resources Information Center

    Wadhwa, Ajay

    2012-01-01

    Some balls which are made of high-quality rubber (an elastomeric) material, such as tennis or squash balls, could be used for the determination of an important property of such materials called resilience. Since a bouncing ball involves a single impact we call this property "rebound resilience" and express it as the ratio of the rebound height to…

  16. Aortic valve repair leads to a low incidence of valve-related complications.

    PubMed

    Aicher, Diana; Fries, Roland; Rodionycheva, Svetlana; Schmidt, Kathrin; Langer, Frank; Schäfers, Hans-Joachim

    2010-01-01

    Aortic valve replacement for aortic regurgitation (AR) has been established as a standard treatment but implies prosthesis-related complications. Aortic valve repair is an alternative approach, but its mid- to long-term results still need to be defined. Over a 12-year period, 640 patients underwent aortic valve repair for regurgitation of a unicuspid (n=21), bicuspid (n=205), tricuspid (n=411) or quadricuspid (n=3) aortic valve. The mechanism of regurgitation involved prolapse (n=469) or retraction (n=20) of the cusps, and dilatation of the root (n=323) or combined pathologies. Treatment consisted of cusp repair (n=529), root repair (n=323) or a combination of both (n=208). The patients were followed clinically and echocardiographically; follow-up was complete in 98.5% (cumulative follow-up: 3035 patient years). Hospital mortality was 3.4% in the total patient cohort and 0.8% for isolated aortic valve repair. The incidences of thrombo-embolism (0.2% per patient per year) and endocarditis (0.16%per patient per year) were low. Freedom from re-operation at 5 and 10 years was 88% and 81% in bicuspid and 97% and 93% in tricuspid aortic valves (p=0.0013). At re-operation, 13 out of 36 valves could be re-repaired. Freedom from valve replacement was 95% and 90% in bicuspid and 97% and 94% in tricuspid aortic valves (p=0.36). Freedom from all valve-related complications at 10 years was 88%. Reconstructive surgery of the aortic valve is feasible with low mortality in many individuals with aortic regurgitation. Freedom from valve-related complications after valve repair seems superior compared to available data on standard aortic valve replacement. Copyright 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

  17. Improved Ball-and-Socket Docking Mechanism

    NASA Technical Reports Server (NTRS)

    Cloyd, Richard; Bryan, Tom

    2004-01-01

    A proposed docking mechanism would form a ball-and-socket joint in the docked condition. The mechanism could tolerate significant initial misalignment because it would include an alignment cone that would guide the ball into the socket. Like other ball-and-socket joints, the joint would have three rotational degrees of freedom. This docking mechanism would be a successor to the one described in Passive Capture Joint With Three Degrees of Freedom (MFS-31146), NASA Tech Briefs, Vol. 22, No. 7 (July 1998), page 65. It would contain most of the components of the prior mechanism, plus some additional components that would expand its capabilities.

  18. Designing Hollow Nano Gold Golf Balls

    PubMed Central

    2015-01-01

    Hollow/porous nanoparticles, including nanocarriers, nanoshells, and mesoporous materials have applications in catalysis, photonics, biosensing, and delivery of theranostic agents. Using a hierarchical template synthesis scheme, we have synthesized a nanocarrier mimicking a golf ball, consisting of (i) solid silica core with a pitted gold surface and (ii) a hollow/porous gold shell without silica. The template consisted of 100 nm polystyrene beads attached to a larger silica core. Selective gold plating of the core followed by removal of the polystyrene beads produced a golf ball-like nanostructure with 100 nm pits. Dissolution of the silica core produced a hollow/porous golf ball-like nanostructure. PMID:24937196

  19. Valve

    DOEpatents

    Cho, Nakwon

    1980-01-01

    A positive acting valve suitable for operation in a corrosive environment is provided. The valve includes a hollow valve body defining an open-ended bore for receiving two, axially aligned, spaced-apart, cylindrical inserts. One insert, designated the seat insert, terminates inside the valve body in an annular face which lies within plane normal to the axis of the two inserts. An elastomeric O-ring seal is disposed in a groove extending about the annular face. The other insert, designated the wedge insert, terminates inside the valve body in at least two surfaces oppositely inclined with respect to each other and with respect to a plane normal to the axis of the two inserts. An elongated reciprocable gate, movable between the two inserts along a path normal to the axis of the two inserts, has a first flat face portion disposed adjacent and parallel to the annular face of the seat insert. The gate has a second face portion opposite to the first face portion provided with at least two oppositely inclined surfaces for mating with respective inclined surfaces of the wedge insert. An opening is provided through the gate which registers with a flow passage through the two inserts when the valve is open. Interaction of the respective inclined surfaces of the gate and wedge insert act to force the first flat face portion of the gate against the O-ring seal in the seat insert at the limits of gate displacement where it reaches its respective fully open and fully closed positions.

  20. How Magnus Bends the Flying Ball - Experimenting and Modeling

    NASA Astrophysics Data System (ADS)

    Timková, V.; Ješková, Z.

    2017-02-01

    Students are well aware of the effect of the deflection of sports balls when they have been given a spin. A volleyball, tennis, or table tennis ball served with topspin results in an additional downward force that makes the ball difficult to catch and return. In soccer, the effect of sidespin causes the ball to curve unexpectedly sideways, resulting in a so-called banana kick that can confuse the goalkeeper. These surprising effects attract students' attention such that the motion of sports balls can be used to capture the interest of students towards the physics behind it. However, to study and analyze the motion of a real ball kicked in a playfield is not an easy task. Instead of the large-scale full-size sports ball motion, there can be designed and studied simpler experiments that can be carried out in the classroom. Moreover, digital technologies that are available at schools enable students to collect data from the experiment easily in a reasonable time. The mathematical model based on the analysis of forces acting on the ball flying in the air can be used to simulate the motion in order to understand the basic physical principles of the motion so that the best correspondence may be found.

  1. The geometrical effect of different annuloplasty rings on mitral valve annulus.

    PubMed

    Al-Maisary, Sameer; Graser, Bastian; Engelhardt, Sandy; Wolf, Ivo; Karck, Matthias; DE Simone, Raffaele

    2017-06-01

    Different types of mitral annuloplasty rings are commercially available. The aim of this study was to investigate the effect of implantation of six types of annuloplasty rings on the geometry and dynamics of the mitral valve. Three-dimensional echocardiography images of 42 patients were acquired to visualize the mitral valve annulus. Virtual representations of six commercially available annuloplasty rings were matched to anatomical mitral annuli of each patient according to anterolateral-posteromedial diameter. The virtual displacement of each annuloplasty ring after the implantation was measured and compared with the other rings. Patients with severe mitral regurgitation had significantly dilated annuli according to anterolateral-posteromedial diameter, anterior-posterior diameter and to annulus circumference. Anterior and posterior heights of the mitral annuli and non-planarity angle showed no significant differences among different patients with different degree of mitral regurgitation. The ratio of anterior-posterior to anterolateral-posteromedial diameter was almost identical in all groups with identical annular shapes. The implantation of the Carpentier-Edwards Classic Annuloplasty Ring™ led to maximal displacement of mitral annulus, followed by the IM-Ring™, without a statistical significance. In contrary, the implantation of a MyxoETlogix Ring™ was associated with minimal displacement of mitral annulus throughout the groups, but without statistical significance. The implantation of different ring types in patients with different annuli shapes and dimensions did not lead to any significant change in the configuration of mitral annuli after the virtual implantation of the tested annuloplasty rings.

  2. Finite element analysis of the axial stiffness of a ball screw

    NASA Astrophysics Data System (ADS)

    Zhou, L.-X.; Li, P.-Y.

    2018-06-01

    The ball screw was developed for high speed and high precision operation; therefore, increasingly greater demands have been placed on the stiffness of the ball screw. Firstly, ANSYS software was used to compare the axial stiffness of a single-nut and single-arc ball screw and a single-nut and double-arc ball screw when the spiral angle is not considered. On this basis, the model of a single-nut ball screw was established taking into consideration the spiral lead angle, and then the variations in displacement and stiffness when the ball screw pair was subjected to an axial force were determined. The axial contact stiffness of the double-nut ball screw pair, subject to a pre-tightening force, was analyzed, according to the above-mentioned steps. The simulation results demonstrated that under the same working conditions, the stiffness of the double-arc ball screw was larger by between 5∼100 N/um than that of the single-arc ball screw. The spiral lead angle increased the axial stiffness of the ball screw pair, and the axial stiffness of the double-nut ball screw pair subject to a pre-tightening force was larger by between 790∼1360 N/um than that of the axial stiffness of the single-nut ball screw pair.

  3. Transseptal antegrade transcatheter aortic valve replacement for patients with no other access approach - a contemporary experience.

    PubMed

    Cohen, Mauricio G; Singh, Vikas; Martinez, Claudia A; O'Neill, Brian P; Alfonso, Carlos E; Martinezclark, Pedro O; Heldman, Alan W; O'Neill, William W

    2013-11-15

    To assess the feasibility and outcomes in patients undergoing transvenous transseptal (TS) transcatheter aortic valve replacement (TAVR). TS approach for TAVR was abandoned in favor of retrograde transfemoral, transaortic, or transapical approaches. TS TAVR may still be warranted in patients for whom no other approach is feasible. Observational consecutive case series at a single center, to evaluate technical outcomes in inoperable patients with aortic stenosis who had contraindications for other approaches and who underwent TAVR via a transvenous TS antegrade approach using the Edwards-Sapien (ES) valve. Over a 4-month period, 9 patients underwent TS TAVR with 26 mm (n = 4) and 23 mm (n = 5) ES valves. Mean age was 84.5 ± 6.6 years and Society of Thoracic Surgeons predicted risk of mortality was 7.8 ± 2.8%. Specific contraindications for other access included iliofemoral arterial diameter <7 mm in 9 (100%), porcelain aorta in 6 (66%) patients, multiple (≥2) sternotomies in 2 (22%) patients, severe pulmonary disease in 3 (33%), extreme frailty in 1 (11%), spinal stenosis with impaired ability to rehabilitate postsurgery in 1 (11%) and apical left ventricular thrombus in 1 (11%) patient. Antegrade deployment of the ES prosthetic valve was technically feasible in 8 patients. Major bleeding occurred in 4 patients, two patients suffered acute kidney injury without need for dialysis and one patient required a permanent pacemaker. The median (25th, 75th percentiles) fluoroscopy time was 49 (34, 81) minutes and contrast volume was 150 (120, 225) ml. No patient had hemodynamically significant post-TAVR aortic insufficiency nor damage to the mitral valve. At 6 months follow-up, there were no cerebrovascular events or rehospitalizations and mean NYHA Class improved from 3.4 to 1.7. The antegrade TS approach to TAVR is a technically feasible option for "no-access" patients. Prospective assessment of the safety and efficacy of this approach in the current era warrants

  4. Multi-port valve assembly

    DOEpatents

    Guggenheim, S. Frederic

    1986-01-01

    A multi-port fluid valve apparatus is used to control the flow of fluids through a plurality of valves and includes a web, which preferably is a stainless steel endless belt. The belt has an aperture therethrough and is progressed, under motor drive and control, so that its aperture is moved from one valve mechanism to another. Each of the valve mechanisms comprises a pair of valve blocks which are held in fluid-tight relationship against the belt. Each valve block consists of a block having a bore through which the fluid flows, a first seal surrounding the bore and a second seal surrounding the first seal, with the distance between the first and second seals being greater than the size of the belt aperture. In order to open a valve, the motor progresses the belt aperture to where it is aligned with the two bores of a pair of valve blocks, such alignment permitting a flow of the fluid through the valve. The valve is closed by movement of the belt aperture and its replacement, within the pair of valve blocks, by a solid portion of the belt.

  5. SOUTHEAST AND NORTHEAST SIDES. Looking west Edwards Air Force ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SOUTHEAST AND NORTHEAST SIDES. Looking west - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Fuel & Water Tank, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  6. SOUTH FRONT AND EAST SIDE. January, 1998 Edwards Air ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SOUTH FRONT AND EAST SIDE. January, 1998 - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Electrical Substation, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  7. Valve in valve transcatheter aortic valve implantation (ViV-TAVI) versus redo-Surgical aortic valve replacement (redo-SAVR): A systematic review and meta-analysis.

    PubMed

    Nalluri, Nikhil; Atti, Varunsiri; Munir, Abdullah B; Karam, Boutros; Patel, Nileshkumar J; Kumar, Varun; Vemula, Praveen; Edla, Sushruth; Asti, Deepak; Paturu, Amrutha; Gayam, Sriramya; Spagnola, Jonathan; Barsoum, Emad; Maniatis, Gregory A; Tamburrino, Frank; Kandov, Ruben; Lafferty, James; Kliger, Chad

    2018-05-20

    Bioprosthetic (BP) valves have been increasingly used for aortic valve replacement over the last decade. Due to their limited durability, patients presenting with failed BP valves are rising. Valve in Valve - Transcatheter Aortic Valve Implantation (ViV-TAVI) emerged as an alternative to the gold standard redo-Surgical Aortic Valve Replacement (redo-SAVR). However, the utility of ViV-TAVI is poorly understood. A systematic electronic search of the scientific literature was done in PubMed, EMBASE, SCOPUS, Google Scholar, and ClinicalTrials.gov. Only studies which compared the safety and efficacy of ViV-TAVI and redo-SAVR head to head in failed BP valves were included. Six observational studies were eligible and included 594 patients, of whom 255 underwent ViV- TAVI and 339 underwent redo-SAVR. There was no significant difference between ViV-TAVI and redo- SAVR for procedural, 30 day and 1 year mortality rates. ViV-TAVI was associated with lower risk of permanent pacemaker implantation (PPI) (OR: 0.43, CI: 0.21-0.89; P = 0.02) and a trend toward increased risk of paravalvular leak (PVL) (OR: 5.45, CI: 0.94-31.58; P = 0.06). There was no significant difference for stroke, major bleeding, vascular complications and postprocedural aortic valvular gradients more than 20 mm-hg. Our results reiterate the safety and feasibility of ViV-TAVI for failed aortic BP valves in patients deemed to be at high risk for surgery. VIV-TAVI was associated with lower risk of permanent pacemaker implantation with a trend toward increased risk of paravalvular leak. © 2018, Wiley Periodicals, Inc.

  8. Thrombocytopenia after aortic valve replacement with freedom solo bioprosthesis: a propensity study.

    PubMed

    Piccardo, Alessandro; Rusinaru, Dan; Petitprez, Benoit; Marticho, Paul; Vaida, Ioana; Tribouilloy, Christophe; Caus, Thierry

    2010-05-01

    The incidence of postoperative thrombocytopenia after aortic valve replacement with the Freedom Solo bioprosthesis remains unclear. This propensity-matched study was carried out to evaluate the incidence and clinical impact of thrombocytopenia in patients receiving the Freedom Solo bioprosthesis. Patients who underwent aortic valve replacement with a Freedom Solo or Carpentier-Edwards Perimount pericardial prosthesis at our institution between 2006 and 2008 were screened retrospectively. Exclusion criteria included double valve replacement, redo surgery, and active endocarditis. Two hundred six patients were considered eligible for this analysis. Using propensity scores 36 matched pairs of patients with a Freedom Solo or Perimount bioprosthesis were obtained. The primary end point was the occurrence of postoperative thrombocytopenia. Secondary end points were postoperative thromboembolic or hemorrhagic events and 30-day mortality. Before matching, severe thrombocytopenia (<30 x 10(9) platelets/L) occurred in 22% of patients with a Freedom Solo bioprosthesis and 1% with a Perimount bioprosthesis (p < 0.0001), thromboembolic or hemorrhagic events occurred in 3% and 2%, respectively (p = 0.37), and 30-day mortality was 4% and 6%, respectively (p = 0.48). Multivariate analysis identified preoperative platelet count (p = 0.01) and Freedom Solo (p < 0.0001) as independent risk factors for severe postoperative thrombocytopenia. After matching, severe thrombocytopenia occurred in 25% and 3% of patients with Freedom Solo and Perimount bioprostheses, respectively (p < 0.0001), thromboembolic or hemorrhagic events occurred in 0%, and 30-day mortality was 3% and 6%, respectively (p = 0.99). The risk of thrombocytopenia was high after Freedom Solo implantation. However, this complication was not related to any deleterious events in our study population. Copyright (c) 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  9. Force measuring valve assemblies, systems including such valve assemblies and related methods

    DOEpatents

    DeWall, Kevin George [Pocatello, ID; Garcia, Humberto Enrique [Idaho Falls, ID; McKellar, Michael George [Idaho Falls, ID

    2012-04-17

    Methods of evaluating a fluid condition may include stroking a valve member and measuring a force acting on the valve member during the stroke. Methods of evaluating a fluid condition may include measuring a force acting on a valve member in the presence of fluid flow over a period of time and evaluating at least one of the frequency of changes in the measured force over the period of time and the magnitude of the changes in the measured force over the period of time to identify the presence of an anomaly in a fluid flow and, optionally, its estimated location. Methods of evaluating a valve condition may include directing a fluid flow through a valve while stroking a valve member, measuring a force acting on the valve member during the stroke, and comparing the measured force to a reference force. Valve assemblies and related systems are also disclosed.

  10. Magnetically operated check valve

    NASA Technical Reports Server (NTRS)

    Morris, Brian G. (Inventor); Bozeman, Richard J., Jr. (Inventor)

    1994-01-01

    A magnetically operated check valve is disclosed. The valve is comprised of a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  11. Magnetically operated check valve

    NASA Astrophysics Data System (ADS)

    Morris, Brian G.; Bozeman, Richard J., Jr.

    1994-06-01

    A magnetically operated check valve is disclosed. The valve is comprised of a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  12. Edward Weston and the "Modern" Galvanometer Movement

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    2008-01-01

    One of my favorite 19th century electrical scientists is Edward Weston, and one of my favorite devices for teaching the topics of electromagnetic forces and torques is the D'Arsonval galvanometer. The junction of these two topics is Weston's improved meter movement that has been used in analog meters for the past 125 years.

  13. PRINCE EDWARD COUNTY, AV HELPS VIRGINIA'S DEPRIVED.

    ERIC Educational Resources Information Center

    EDGERTON, WILBERT D.

    DISCUSSED IS THE ESTABLISHMENT OF THE PRINCE EDWARD COUNTY FREE SCHOOLS IN VIRGINIA. MANY OF THE CHILDREN HAD NOT ATTENDED SCHOOLS FOR 4 YEARS FOLLOWING THE CLOSURE OF THE PUBLIC SCHOOLS AND, THEREFORE, THE TRADITIONAL EDUCATIONAL PROGRAM WAS FELT TO BE INADEQUATE FOR THESE STUDENTS. THE FREE SCHOOLS INITIATED UNGRADED CLASSES, TEAM TEACHING, AN…

  14. 4. NORTHWEST FRONT, WITH FOUR BULLET GLASS WINDOWS. Edwards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. NORTHWEST FRONT, WITH FOUR BULLET GLASS WINDOWS. - Edwards Air Force Base, South Base Sled Track, Observation Block House, Station "O" area, east end of Sled Track, Lancaster, Los Angeles County, CA

  15. Supersymmetric Q-balls: A numerical study

    NASA Astrophysics Data System (ADS)

    Campanelli, L.; Ruggieri, M.

    2008-02-01

    We study numerically a class of nontopological solitons, the Q-balls, arising in a supersymmetric extension of the standard model with low-energy, gauge-mediated symmetry breaking. Taking into account the exact form of the supersymmetric potential giving rise to Q-balls, we find that there is a lower limit on the value of the charge Q in order to make them classically stable: Q≳5×102Qcr, where Qcr is constant depending on the parameters defining the potential and can be in the range 1≲Qcr≲108÷16. If Q is the baryon number, stability with respect to the decay into protons requires Q≳1017Qcr, while if the gravitino mass is greater then m3/2≳61MeV, no stable gauge-mediation supersymmetric Q-balls exist. Finally, we find that energy and radius of Q-balls can be parametrized as E˜ξEQ3/4 and R˜ξRQ1/4, where ξE and ξR are slowly varying functions of the charge.

  16. Aortic valve insufficiency in the teenager and young adult: the role of prosthetic valve replacement.

    PubMed

    Bradley, Scott M

    2013-10-01

    The contents of this article were presented in the session "Aortic insufficiency in the teenager" at the congenital parallel symposium of the 2013 Society of Thoracic Surgeons (STS) annual meeting. The accompanying articles detail the approaches of aortic valve repair and the Ross procedure.(1,2) The current article focuses on prosthetic valve replacement. For many young patients requiring aortic valve surgery, either aortic valve repair or a Ross procedure provides a good option. The advantages include avoidance of anticoagulation and potential for growth. In other patients, a prosthetic valve is an appropriate alternative. This article discusses the current state of knowledge regarding mechanical and bioprosthetic valve prostheses and their specific advantages relative to valve repair or a Ross procedure. In current practice, young patients requiring aortic valve surgery frequently undergo valve replacement with a prosthetic valve. In STS adult cardiac database, among patients ≤30 years of age undergoing aortic valve surgery, 34% had placement of a mechanical valve, 51% had placement of a bioprosthetic valve, 9% had aortic valve repair, and 2% had a Ross procedure. In the STS congenital database, among patients 12 to 30 years of age undergoing aortic valve surgery, 21% had placement of a mechanical valve, 18% had placement of a bioprosthetic valve, 30% had aortic valve repair, and 24% had a Ross procedure. In the future, the balance among these options may be altered by design improvements in prosthetic valves, alternatives to warfarin, the development of new patch materials for valve repair, and techniques to avoid Ross autograft failure.

  17. 7. DETAIL SHOWING BLAST SHIELDED WINDOWS, WEST SIDE. Edwards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. DETAIL SHOWING BLAST SHIELDED WINDOWS, WEST SIDE. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  18. CONTROL BUILDING, WEST FRONT SHOWING ENTRANCE Edwards Air Force ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CONTROL BUILDING, WEST FRONT SHOWING ENTRANCE - Edwards Air Force Base, X-15 Engine Test Complex, Firing Control Building, Rogers Dry Lake, east of runway between North Base & South Base, Boron, Kern County, CA

  19. 7. INTERIOR, STEEL BLAST DOORS, INSTRUMENTATION ROOM. Edwards Air ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. INTERIOR, STEEL BLAST DOORS, INSTRUMENTATION ROOM. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-4, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  20. 4. DETAIL SHOWING FLAME DEFLECTOR. Looking southeast. Edwards Air ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. DETAIL SHOWING FLAME DEFLECTOR. Looking southeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  1. Embolic capture with updated intra-aortic filter during coronary artery bypass grafting and transaortic transcatheter aortic valve implantation: first-in-human experience.

    PubMed

    Ye, Jian; Webb, John G

    2014-12-01

    We report our first-in-human clinical experience in the use of the new version of the EMBOL-X intra-aortic filter (Edwards Lifesciences Corporation, Irvine, Calif) to capture embolic material during transaortic transcatheter aortic valve implantation and cardiac surgery. Five patients were enrolled into the first-in-human clinical assessment of the new version of the EMBOL-X intra-aortic filter. Three patients underwent coronary artery bypass grafting, and 2 patients underwent transaortic transcatheter aortic valve implantation. During coronary artery bypass grafting, the filter was deployed before clamping of the aorta and removal of the aortic clamp. In contrast, the filter was deployed before aortic puncture for transaortic transcatheter aortic valve implantation and kept in the aorta throughout the entire procedure. The filter introducer sheath and filter were easily placed and removed without difficulty. There were no complications related to the use of the filter. Postoperative examination of the retrieved filters revealed the presence of multiple microemboli in the filters from all 5 cases. Histologic study revealed various kinds of tissue and thrombus. This first-in-human clinical experience has demonstrated the safety and feasibility of using the new version of the EMBOL-X intra-aortic filter during either cardiac surgery or transaortic transcatheter aortic valve implantation. We believe that the combination of the transaortic approach without aortic arch manipulation and the use of the EMBOL-X filter with a high capture rate is a promising strategy to reduce the incidence of embolic complications during transcatheter aortic valve implantation. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  2. NCI and Leidos Play Ball | Poster

    Cancer.gov

    By Carolynne Keenan, Contributing Writer The ping of an aluminum bat off a ball or the thump of a pop-up fly ball caught in a glove are two sounds familiar to baseball fans. Slow-pitch softball sounds—like those in the August game between mixed teams of NCI and Leidos Biomedical Research (formerly SAIC-Frederick) players—are similar.

  3. Automatic shutoff valve

    NASA Technical Reports Server (NTRS)

    Hawkins, S. F.; Overbey, C. W.

    1980-01-01

    Cellulose-sponge disk absorbs incoming water and expands with enough force to shut valve. When water recedes, valve opens by squeezing sponge dry to its original size. This direct mechanical action is considered more reliable than solenoid valve.

  4. Transcatheter aortic valve-in-valve treatment of degenerative stentless supra-annular Freedom Solo valves: A single centre experience.

    PubMed

    Cockburn, James; Dooley, Maureen; Parker, Jessica; Hill, Andrew; Hutchinson, Nevil; de Belder, Adam; Trivedi, Uday; Hildick-Smith, David

    2017-02-15

    Redo surgery for degenerative bioprosthetic aortic valves is associated with significant morbidity and mortality. Report results of valve-in-valve therapy (ViV-TAVI) in failed supra-annular stentless Freedom Solo (FS) bioprostheses, which are the highest risk for coronary occlusion. Six patients with FS valves (mean age 78.5 years, 50% males). Five had valvular restenosis (peak gradient 87.2 mm Hg, valve area 0.63 cm 2 ), one had severe regurgitation (AR). Median time to failure was 7 years. Patients were high risk (mean STS/Logistic EuroScore 10.6 15.8, respectively). FS valves ranged from 21 to 25 mm. Successful ViV-TAVI was achieved in 4/6 patients (67%). Of the unsuccessful cases, (patient 1 and 2 of series) patient 1 underwent BAV with simultaneous aortography which revealed left main stem occlusion. The procedure was stopped and the patient went forward for repeat surgery. Patient 2 underwent successful ViV-TAVI with a 26-mm CoreValve with a guide catheter in the left main, but on removal coronary obstruction occurred, necessitating valve snaring into the aorta. Among the successful cases, (patients 3, 4, 5, 6) the TAVIs used were CoreValve Evolut R 23 mm (n = 3), and Lotus 23 mm (n = 1). In the successful cases the peak gradient fell from 83.0 to 38.3 mm Hg. No patient was left with >1+ AR. One patient had a stroke on Day 2, with full neurological recovery. Two patients underwent semi-elective pacing for LBBB and PR >280 ms. ViV-TAVI in stentless Freedom Solo valves is high risk. The risk of coronary occlusion is high. The smallest possible prosthesis (1:1 sizing) should be used, and strategies to protect the coronary vessels must be considered. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. CFD Analysis of Swing of Cricket Ball and Trajectory Prediction

    NASA Astrophysics Data System (ADS)

    G, Jithin; Tom, Josin; Ruishikesh, Kamat; Jose, Jyothish; Kumar, Sanjay

    2013-11-01

    This work aims to understand the aerodynamics associated with the flight and swing of a cricket ball and predict its flight trajectory over the course of the game: at start (smooth ball) and as the game progresses (rough ball). Asymmetric airflow over the ball due to seam orientation and surface roughness can cause flight deviation (swing). The values of Drag, Lift and Side forces which are crucial for determining the trajectory of the ball were found with the help of FLUENT using the standard K- ɛ model. Analysis was done to study how the ball velocity, spin imparted to be ball and the tilt of the seam affects the movement of the ball through air. The governing force balance equations in 3 dimensions in combination a MATLAB code which used Heun's method was used for obtaining the trajectory of the ball. The conditions for the conventional swing and reverse swing to occur were deduced from the analysis and found to be in alignment with the real life situation. Critical seam angle for maximum swing and transition speed for normal to reverse swing were found out. The obtained trajectories were compared to real life hawk eye trajectories for validation. The analysis results were in good agreement with the real life situation.

  6. 5. NORTHEAST CORNER. View to southwest from below. Edwards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. NORTHEAST CORNER. View to southwest from below. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-5, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  7. NORTHWEST FRONT AND SOUTHWEST SIDE, BUILDING 1933 Edwards Air ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    NORTHWEST FRONT AND SOUTHWEST SIDE, BUILDING 1933 - Edwards Air Force Base, X-15 Engine Test Complex, Observation Bunker Types, Rogers Dry Lake, east of runway between North Base & South Base, Boron, Kern County, CA

  8. 5. EAST SIDE, TEST STAND AND ITS SUPERSTRUCTURE. Edwards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. EAST SIDE, TEST STAND AND ITS SUPERSTRUCTURE. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  9. 8. SOUTH REAR, SUPERSTRUCTURE. Looking north from deck. Edwards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. SOUTH REAR, SUPERSTRUCTURE. Looking north from deck. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  10. Overflow control valve

    DOEpatents

    Hundal, Rolv; Kessinger, Boyd A.; Parlak, Edward A.

    1984-07-24

    An overflow control valve for use in a liquid sodium coolant pump tank which valve can be extended to create a seal with the pump tank wall or retracted to break the seal thereby accommodating valve removal. An actuating shaft which controls valve disc position also has cams which bear on roller surfaces to force retraction of a sliding cylinder against spring tension to retract the cylinder from sealing contact with the pump tank.

  11. Aerodynamic Shutoff Valve

    NASA Technical Reports Server (NTRS)

    Horstman, Raymond H.

    1992-01-01

    Aerodynamic flow achieved by adding fixed fairings to butterfly valve. When valve fully open, fairings align with butterfly and reduce wake. Butterfly free to turn, so valve can be closed, while fairings remain fixed. Design reduces turbulence in flow of air in internal suction system. Valve aids in development of improved porous-surface boundary-layer control system to reduce aerodynamic drag. Applications primarily aerospace. System adapted to boundary-layer control on high-speed land vehicles.

  12. Mesofluidic two stage digital valve

    DOEpatents

    Jansen, John F; Love, Lonnie J; Lind, Randall F; Richardson, Bradley S

    2013-12-31

    A mesofluidic scale digital valve system includes a first mesofluidic scale valve having a valve body including a bore, wherein the valve body is configured to cooperate with a solenoid disposed substantially adjacent to the valve body to translate a poppet carried within the bore. The mesofluidic scale digital valve system also includes a second mesofluidic scale valve disposed substantially perpendicular to the first mesofluidic scale valve. The mesofluidic scale digital valve system further includes a control element in communication with the solenoid, wherein the control element is configured to maintain the solenoid in an energized state for a fixed period of time to provide a desired flow rate through an orifice of the second mesofluidic valve.

  13. Main Oxidizer Valve Design

    NASA Technical Reports Server (NTRS)

    Addona, Brad; Eddleman, David

    2015-01-01

    A developmental Main Oxidizer Valve (MOV) was designed by NASA-MSFC using additive manufacturing processes. The MOV is a pneumatically actuated poppet valve to control the flow of liquid oxygen to an engine's injector. A compression spring is used to return the valve to the closed state when pneumatic pressure is removed from the valve. The valve internal parts are cylindrical in shape, which lends itself to traditional lathe and milling operations. However, the valve body represents a complicated shape and contains the majority of the mass of the valve. Additive manufacturing techniques were used to produce a part that optimized mass and allowed for design features not practical with traditional machining processes.

  14. Effect of Hoop Stress on Ball Bearing Life Prediction

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.; August, Richard; Coe, Harold H.

    1995-01-01

    A finite-element analysis (FEA) of a generic, dimensionally normalized inner race of an angular-contact ball bearing was performed under varying conditions of speed and the press (or interference) fit of the inner-race bore on a journal. The FEA results at the ball-race contact were used to derive an equation from which was obtained the radius of an equivalent cylindrical bearing race with the same or similar hoop stress. The radius of the equivalent cylinder was used to obtain a generalized closed-form approximation of the hoop stresses at the ball-inner-race contact in an angular-contact ball bearing. A life analysis was performed on both a 45- and a 120-mm-bore, angular-contact ball bearing. The predicted lives with and without hoop stress were compared with experimental endurance results obtained at 12000 and 25000 rpm with the 120-mm-bore ball bearing. A life factor equation based on hoop stress is presented.

  15. Fabrication of nanoscale Ga balls via a Coulomb explosion of microscale silica-covered Ga balls by TEM electron-beam irradiation

    PubMed Central

    Chen, Ying; Huang, Yanli; Liu, Nishuang; Su, Jun; Li, Luying; Gao, Yihua

    2015-01-01

    Nanoscale Ga particles down to 5 nm were fabricated by an explosion via an in situ electron-beam irradiation on microscale silica-covered Ga balls in a transmission electron microscope. The explosion is confirmed to be a Coulomb explosion because it occurs on the surface rather than in the whole body of the insulating silica-covered Ga micro–balls, and on the pure Ga nano-balls on the edge of carbon film. The ejected particles in the explosion increase their sizes with increasing irradiation time until the stop of the explosion, but decrease their sizes with increasing distance from the original ball. The Coulomb explosion suggests a novel method to fabricate nanoscale metal particles with low melting point. PMID:26100238

  16. Heat-balling wasps by honeybees

    NASA Astrophysics Data System (ADS)

    Ken, Tan; Hepburn, H. R.; Radloff, S. E.; Yusheng, Yu; Yiqiu, Liu; Danyin, Zhou; Neumann, P.

    2005-10-01

    Defensiveness of honeybee colonies of Apis cerana and Apis mellifera (actively balling the wasps but reduction of foraging) against predatory wasps, Vespa velutina, and false wasps was assessed. There were significantly more worker bees in balls of the former than latter. Core temperatures in a ball around a live wasp of A. cerana were significantly higher than those of A. mellifera, and also significantly more when exposed to false wasps. Core temperatures of bee balls exposed to false wasps were significantly lower than those exposed to V. velutina for both A. cerana and for A. mellifera. The lethal thermal limits for V. velutina, A. cerana and A. mellifera were significantly different, so that both species of honeybees have a thermal safety factor in heat-killing such wasp predators. During wasps attacks at the hives measured at 3, 6 and 12 min, the numbers of Apis cerana cerana and Apis cerana indica bees continuing to forage were significantly reduced with increased wasp attack time. Tropical lowland A. c. indica reduced foraging rates significantly more than the highland A. c. cerana bees; but, there was no significant effect on foraging by A. mellifera. The latency to recovery of honeybee foraging was significantly greater the longer the duration of wasp attacks. The results show remarkable thermal fine-tuning in a co-evolving predator prey relationship.

  17. Slow opening valve. [valve design for shuttle portable oxygen system

    NASA Technical Reports Server (NTRS)

    Drapeau, D. F. (Inventor)

    1984-01-01

    A valve control is described having a valve body with an actuator stem and a rotating handle connected to the actuator stem by a differential drive mechanism which, during uniform movement of the handle in one direction, initially opens the valve at a relatively slow rate and, thereafter, complete the valve movement at a substantially faster rate. A series of stop rings are received about the body in frictional abutting relationship and serially rotated by the handle to uniformly resist handle movement independently of the extent of handle movement.

  18. The F-18 simulator at NASA's Dryden Flight Research Center, Edwards, California

    NASA Image and Video Library

    2004-10-04

    The F-18 simulator at NASA's Dryden Flight Research Center, Edwards, California. Simulators offer a safe and economical alternative to actual flights to gather data, as well as being excellent facilities for pilot practice and training. The F-18 Hornet is used primarily as a safety chase and mission support aircraft at NASA's Dryden Flight Research Center, Edwards, California. As support aircraft, the F-18's are used for safety chase, pilot proficiency, aerial photography and other mission support functions.

  19. 4. BUILDING 8767, INTERIOR. Looking west. Edwards Air Force ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. BUILDING 8767, INTERIOR. Looking west. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  20. Recent Advances in Transcatheter Aortic Valve Implantation: Novel Devices and Potential Shortcomings

    PubMed Central

    Blumenstein, J.; Liebetrau, C.; Linden, A. Van; Moellmann, H.; Walther, T.; Kempfert, J.

    2013-01-01

    During the past years transcatheter aortic valve implantation (TAVI) has evolved to a standard technique for the treatment of high risk patients suffering from severe aortic stenosis. Worldwide the number of TAVI procedures is increasing exponentially. In this context both the transapical antegrade (TA) and the transfemoral retrograde (TF) approach are predominantly used and can be considered as safe and reproducible access sites for TAVI interventions. As a new technology TAVI is in a constant progress regarding the development of new devices. While in the first years only the Edwards SAPIEN™ and the Medtronic CoreValve™ prostheses were commercial available, recently additional devices obtained CE-mark approval and others have entered initial clinical trials. In addition to enhance the treatment options in general, the main driving factor to further develop new device iterations is to solve the drawbacks of the current TAVI systems: paravalvular leaks, occurrence of AV-blocks and the lack of full repositionability. PMID:24313644