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Sample records for ad contact pratt

  1. 77 FR 65142 - Airworthiness Directives; Pratt & Whitney Canada Corp Turboshaft Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-25

    ... Canada Corp Turboshaft Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of... Pratt & Whitney Canada Corp. (P&WC) PT6C-67C turboshaft engines. This proposed AD was prompted by five... identified in this proposed AD, contact Pratt & Whitney Canada Corp., 1000 Marie-Victorin, Longueuil,...

  2. 75 FR 51657 - Airworthiness Directives; Pratt & Whitney Canada Corp. (P&WC) PW615F-A Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-23

    ...-06] RIN 2120-AA64 Airworthiness Directives; Pratt & Whitney Canada Corp. (P&WC) PW615F-A Turbofan... adding the following new AD: 2010-17-06 Pratt & Whitney Canada Corp. (formerly Pratt & Whitney Canada.... Applicability (c) This AD applies to Pratt & Whitney Canada Corp. PW615F-A turbofan engines with fuel/oil...

  3. 77 FR 30926 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA..., PW4164, PW4168, PW4168A, PW4460, and PW4462 turbofan engines. The existing AD currently requires initial..., Pratt & Whitney has developed a redesigned HPC drum rotor disk assembly for certain affected...

  4. 76 FR 72348 - Airworthiness Directives; Pratt & Whitney Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-23

    ... Directives; Pratt & Whitney Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... Pratt & Whitney JT9D-7R4D, -7R4D1, -7R4E, -7R4E1, -7R4G2, -7R4H1, and - 7R4E4 turbofan engines. This..., P/N 735907, is necessary. We are proposing this AD to prevent critical life-limited rotating...

  5. 75 FR 72653 - Airworthiness Directives; Pratt & Whitney Canada Corp. (P&WC) PW305A and PW305B Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-26

    ... Canada Corp. (P&WC) PW305A and PW305B Turboprop Engines AGENCY: Federal Aviation Administration (FAA... the following new AD: 2010-24-05 Pratt & Whitney Canada Corp. (Formerly Pratt & Whitney Canada, Inc.... Applicability (c) This AD applies to Pratt & Whitney Canada Corp. (P&WC) PW305A and PW305B turboprop...

  6. 77 FR 15939 - Airworthiness Directives; Pratt & Whitney Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are superseding an existing airworthiness directive (AD) for all Pratt & Whitney (PW) JT9D series turbofan engines... the JT9D series engines ALS sections of the manufacturer's ICA. This AD was prompted by the need...

  7. 76 FR 72353 - Airworthiness Directives; Pratt & Whitney Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-23

    ... Directives; Pratt & Whitney Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION...) turbofan engines. This proposed AD was prompted by reports of five engine in-flight shutdowns and seven unplanned engine removals. This proposed AD would require inspections, cleaning, and engine modifications...

  8. 75 FR 27491 - Airworthiness Directives; Pratt & Whitney Canada Corp. PW617F-E Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-17

    ... Canada Corp. PW617F-E Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice... Metering Unit (FMU), resulting in fuel flow drop and subsequent power reduction. Pratt & Whitney Canada... holidays. Fax: (202) 493-2251. Contact Pratt & Whitney Canada Corp., 1000 Marie-Victorin, Longueuil,...

  9. 77 FR 66767 - Airworthiness Directives; Pratt & Whitney Canada Corp. Turboshaft Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-07

    ... & Whitney Canada Corp. Turboshaft Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice... certain serial number Pratt & Whitney Canada Corp. (P&WC) PW206B, PW206B2, PW206C, PW207C, PW207D, PW207D1..., contact Pratt & Whitney Canada Corp., 1000 Marie-Victorin, Longueuil, Quebec, Canada, J4G 1A1; phone...

  10. 77 FR 39624 - Airworthiness Directives; Pratt & Whitney Canada Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-05

    ...-14] RIN 2120-AA64 Airworthiness Directives; Pratt & Whitney Canada Turboprop Engines AGENCY: Federal..., PW126A, PW127, PW127E, PW127F, PW127G, and PW127M turboprop engines. This AD requires initial and...; Web site: www.pwc.ca. You may review copies of the referenced service information at the FAA,...

  11. 76 FR 78526 - Airworthiness Directives; Eclipse Aerospace, Inc. Airplanes Equipped With Pratt & Whitney Canada...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-19

    ...-005-AD; Amendment 39-16890; AD 2011-06-06 R1] RIN 2120-AA64 Airworthiness Directives; Eclipse... directive (AD) that applies to all Eclipse Aerospace, Inc. Model EA500 airplanes equipped with Pratt...: 2011-06-06 R1 Eclipse Aerospace, Inc.: Amendment 39-16890; Docket No. FAA-2011-0199;...

  12. EXTERIOR VIEW, BEE HIVE COKE OVEN DOOR. Pratt Coal ...

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

    EXTERIOR VIEW, BEE HIVE COKE OVEN DOOR. - Pratt Coal & Coke Company, Pratt Mines, Coke Ovens & Railroad, Bounded by First Street, Avenue G, Third Place, Birmingham Southern Railroad, Birmingham, Jefferson County, AL

  13. 13. PRATT STREET BULKHEAD: SECTIONS 2, 3, 4, 5, AND ...

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

    13. PRATT STREET BULKHEAD: SECTIONS 2, 3, 4, 5, AND 6, DRAWER 10, PLAN NO. 1, 1 IN. = 15 FT. AND 1/2 IN. = 1 FT., APRIL 25, 1906, DRAWING SHOWS DESIGN FOR PRATT STREET BULKHEAD BETWEEN PIERS - Baltimore Inner Harbor, Pier 5, South of Pratt Street between Market Place & Concord Street, Baltimore, Independent City, MD

  14. 78 FR 11565 - Airworthiness Directives; Pratt & Whitney Canada Corp. Turboshaft Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-19

    ... Canada Corp. Turboshaft Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule... Canada Corp. PW206B, PW206B2, PW206C, PW207C, PW207D, PW207D1, PW207D2, and PW207E turboshaft engines... amends Sec. 39.13 by adding the following new AD: 2013-03-21 Pratt & Whitney Canada Corp.: Amendment...

  15. 75 FR 50945 - Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, -217C, and -219 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... JT8D-209, -217, -217A, -217C, and -219 Turbofan Engines AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Pratt & Whitney (PW) JT8D-209, -217, -217A, -217C, and -219 turbofan engines. That AD currently requires revisions to the engine manufacturer's time limits section (TLS) to...

  16. 76 FR 77107 - Airworthiness Directives; Pratt & Whitney Corp. (PW) JT9D-7R4H1 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-12

    ... Administration 14 CFR Part 39 [Docket No. FAA-2011-0731; Directorate Identifier 2010-NE-39-AD; Amendment 39-16886; AD 2011-25-10] RIN 2120-AA64 Airworthiness Directives; Pratt & Whitney Corp. (PW) JT9D-7R4H1 Turbofan... new airworthiness directive (AD) for all PW JT9D-7R4H1 turbofan engines. This AD was prompted...

  17. Antifungal activity by vapor contact of essential oils added to amaranth, chitosan, or starch edible films.

    PubMed

    Avila-Sosa, Raúl; Palou, Enrique; Jiménez Munguía, María Teresa; Nevárez-Moorillón, Guadalupe Virginia; Navarro Cruz, Addí Rhode; López-Malo, Aurelio

    2012-02-01

    Antimicrobial agents can be incorporated into edible films to provide microbiological stability, since films can be used as carriers of a variety of additives to extend product shelf life and reduce the risk of microbial growth on food surfaces. Addition of antimicrobial agents to edible films offers advantages such as the use of small antimicrobial concentrations and low diffusion rates. The aim of this study was to evaluate inhibition by vapor contact of Aspergillus niger and Penicillium digitatum by selected concentrations of Mexican oregano (Lippia berlandieri Schauer), cinnamon (Cinnamomum verum) or lemongrass (Cymbopogon citratus) essential oils (EOs) added to amaranth, chitosan, or starch edible films. Essential oils were characterized by gas chromatography-mass spectrometry (GC/MS) analysis. Amaranth, chitosan and starch edible films were formulated with essential oil concentrations of 0.00, 0.25, 0.50, 0.75, 1.00, 2.00, or 4.00%. Antifungal activity was evaluated by determining the mold radial growth on agar media inoculated with A. niger and P. digitatum after exposure to vapors arising from essential oils added to amaranth, chitosan or starch films using the inverted lid technique. The modified Gompertz model adequately described mold growth curves (mean coefficient of determination 0.991 ± 0.05). Chitosan films exhibited better antifungal effectiveness (inhibition of A. niger with 0.25% of Mexican oregano and cinnamon EO; inhibition of P. digitatum with 0.50% EOs) than amaranth films (2.00 and 4.00% of cinnamon and Mexican oregano EO were needed to inhibit the studied molds, respectively). For chitosan and amaranth films a significant increase (p<0.05) of lag phase was observed among film concentrations while a significant decrease (p<0.05) of maximum specific growth was determined. Chitosan edible films incorporating Mexican oregano or cinnamon essential oil could improve the quality of foods by the action of the volatile compounds on surface growth

  18. 7. CONNECTION PIER #4 TO PRATT ST. BULKHEAD WITH HANDWRITTEN ...

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

    7. CONNECTION PIER #4 TO PRATT ST. BULKHEAD WITH HANDWRITTEN CONSTRUCTION CONTRACT BETWEEN O.F. LACKEY AND SANFORD & BROOKS CO, DWG. 144, 1" = 1', MADE BY H.S. - Baltimore Inner Harbor, Pier 4, South side of Pratt Street between Frederick Street & Market Place, Baltimore, Independent City, MD

  19. Professing in the Contact Zone: Bringing Theory and Practice Together.

    ERIC Educational Resources Information Center

    Wolff, Janice M., Ed.

    This collection of essays brings together Mary Louise Pratt's original essay, the 10-year-old "Professing in the Contact Zone," with 14 responses that interpret, extend, and challenge Pratt's work. The essays examine how contact zone dynamics play out in various pedagogical spaces. Following an introduction by the editor, essays in…

  20. Percutaneous Retrieval of a Retained Jackson-Pratt Drain Fragment

    SciTech Connect

    Namyslowski, Jan; Halin, Neil J.; Greenfield, Alan J.

    1996-11-15

    A retained intraabdominal Jackson-Pratt drain fragment was percutaneously retrieved using an inflated angioplasty balloon that had been maneuvered inside of the drain lumen over a hydrophilic-coated steerable guidewire.

  1. 77 FR 16967 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ... field event led Pratt & Whitney to re-evaluate the low- cycle fatigue analysis of the PW2000 engine and..., call 781-238-7125. Issued in Burlington, Massachusetts, on March 14, 2012. Peter A. White,...

  2. 75 FR 52368 - Notice of Inventory Completion: Homer Society of Natural History, Pratt Museum, Homer, AK

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-25

    ... Completion: Homer Society of Natural History, Pratt Museum, Homer, AK AGENCY: National Park Service, Interior... of the Homer Society of Natural History, Pratt Museum, Homer, AK. The human remains were removed...

  3. AERIAL OVERVIEW, LOOKING WEST TOWARD PRATT CITY, WITH EXTRACTION OPERATIONS ...

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

    AERIAL OVERVIEW, LOOKING WEST TOWARD PRATT CITY, WITH EXTRACTION OPERATIONS (BOTTOM LEFT AND CENTER), COKE BY-PRODUCT PLANT (CENTER), AND THE FORMER THOMAS FURNACE COMMUNITY, NOW THE THOMAS NATIONAL REGISTER HISTORIC DISTRICT (CENTER RIGHT). - Wade Sand & Gravel Company, AL 78, Thomas, Jefferson County, AL

  4. Pratt and Whitney cryogenic turbopump bearing experience

    NASA Technical Reports Server (NTRS)

    Poole, W. E.; Bursey, R. W., Jr.

    1988-01-01

    Successful, reusable bearings require lubrication, traditionally, a transfer film from sacrificial cage wear. Early testing included materials screening programs to identify suitable cryogenic cage materials. A specially developed element tester that simulated the function of a ball bearing cage was used. Suitable materials must provide lubrication with an acceptably low wear rate, without abrading contacting surfaces. The most promising materials were tested in full scale bearings at speeds up to 4 MDN. Teflon, filled with 40 percent bronze powder, was the best performing material. A variety of bearings were designed and successfully tested in LH2 and LOX. Bearings with bronze filled Teflon cages were successfully tested for 150 hrs. In overload tests, the same design was tested for 5 hrs at maximum Hertz stresses above 450 ksi and an additional 5 hrs with a maximum Hertz stress exceeding 500 ksi. Four bearings were tested in LOX for 25 hrs, with a maximum time per bearing of 10 hrs.

  5. 75 FR 51659 - Airworthiness Directives; Pratt & Whitney Canada Corp. PW617F-E Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-23

    ...-01] RIN 2120-AA64 Airworthiness Directives; Pratt & Whitney Canada Corp. PW617F-E Turbofan Engines... & Whitney Canada Corp. issued an Alert Service Bulletin (ASB) No. PW600-72-A66019 to inspect and replace any... power reduction. Pratt & Whitney Canada Corp. issued an ASB No. PW600-72-A66019 to inspect and...

  6. 75 FR 27489 - Airworthiness Directives; Pratt & Whitney Canada Corp. PW615F-A Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-17

    ... Canada Corp. PW615F-A Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice... Metering Unit (FMU), resulting in fuel flow drop and subsequent power reduction. Pratt & Whitney Canada... Pratt & Whitney Canada Corp. has confirmed similar dormant failure of worn through poppets of...

  7. The Pratt Center for Community Improvement: A University Urban Action Program.

    ERIC Educational Resources Information Center

    Raymond, George M.; Shiffman, Ronald

    The Pratt Center for Community Improvement was founded in Brooklyn in 1963 by Pratt Institute. Its aim was to help equalize the knowledge level of city and community representatives concerning issues in urban renewal, and to gain the confidence of local residents and enhance their participation in decision making. Participant education and…

  8. Subsidence and flexure along the Pratt-Welker seamount chain

    NASA Astrophysics Data System (ADS)

    Lambeck, K.; Penney, C. L.; Nakiboglu, S. M.; Coleman, R.

    1984-02-01

    A geophysical examination of the degree of isostatic compensation of guyots in the Pratt-Welker seamount chain in the Gulf of Alaska is presented in order to test the hypothesis of several previous studies that the origin of the Pratt-Welker chain cannot be attributed to a single cause. The test is carried out using GEOS 3 and Seasat altimeter data. The effective flexural rigidity of the lithosphere below all the seamounts in the chain is found to be less than about 10 to the 20th Nm, such that the isostatic state is local rather than regional. This may be the result of all seamounts having formed on an initially weak lithosphere. The subsidence of guyots in the chain is associated with numerous factors including thermal contraction of the seafloor, sediment loading, the flexure of the lithosphere prior to its subduction along the Aleutian Trench, and stress relaxation. The conclusions from the flexure and subsidence analyses are in agreement with the bulk of data from previous studies of the area.

  9. NASA / Pratt and Whitney Collaborative Partnership Research in Ultra High Bypass Cycle Propulsion Concepts

    NASA Technical Reports Server (NTRS)

    Hughes, Chris; Lord, Wed

    2008-01-01

    Current collaborative research with Pratt & Whitney on Ultra High Bypass Engine Cycle noise, performance and emissions improvements as part of the Subsonic Fixed Wing Project Ultra High Bypass Engine Partnership Element is discussed. The Subsonic Fixed Wing Project goals are reviewed, as well as their relative technology level compared to previous NASA noise program goals. Progress toward achieving the Subsonic Fixed Wing Project goals over the 2008 fiscal year by the UHB Partnership in this area of research are reviewed. The current research activity in Ultra High Bypass Engine Cycle technology, specifically the Pratt & Whitney Geared Turbofan, at NASA and Pratt & Whitney are discussed including the contributions each entity bring toward the research project, and technical plans and objectives. Pratt & Whitney Geared Turbofan current and future technology and business plans are also discussed, including the role the NASA SFW UHB partnership plays toward achieving those goals.

  10. Advanced control for airbreathing engines, volume 1: Pratt and Whitney

    NASA Technical Reports Server (NTRS)

    Ralph, J. A.

    1993-01-01

    The application of advanced control concepts to air breathing engines may yield significant improvements in aircraft/engine performance and operability. Screening studies of advanced control concepts for air breathing engines were conducted by three major domestic aircraft engine manufacturers to determine the potential impact of concepts on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed advanced control concepts was formulated and evaluated in a two phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation specific aircraft/engine combinations were considered: a Military High Performance Fighter mission, a High Speed Civil Transport mission, and a Civil Tiltrotor mission. Each of the advanced control concepts considered in the study are defined and described. The concept potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts are determined. Finally, the concepts are ranked with respect to the target aircraft/engine missions. A final report describing the screening studies was prepared by each engine manufacturer. Volume 1 of these reports describes the studies performed by Pratt & Whitney.

  11. 75 FR 14375 - Airworthiness Directives; Pratt & Whitney (PW) PW4000 Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ...) PW4000 Series Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of..., PW4156, PW4156A, PW4158, PW4164, PW4168, PW4168A, PW4460, and PW4462 turbofan engines. This proposed AD... proposed AD. FOR FURTHER INFORMATION CONTACT: Rose Len, Aerospace Engineer, Engine Certification...

  12. 78 FR 49111 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... high-pressure turbine (HPT) air seal part number installed. This AD was prompted by discovery of cracks in second-stage HPT air seals. This AD requires inspection and removal from service of HPT air seals that fail inspection. We are issuing this AD to prevent failure of the second-stage HPT air seal,...

  13. 78 FR 64419 - Airworthiness Directives; Pratt & Whitney Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-29

    ...) case flange. This proposed AD would require a one-time eddy current inspection (ECI) of affected... the effective date of this AD, whichever is earlier, eddy current inspect the diffuser case and the... paragraph (e) of this AD. (g) Credit for Previous Actions If you performed an eddy current inspection of...

  14. Joseph Hersey Pratt (1872-1956): An early proponent of cognitive-behavioural therapy in America.

    PubMed

    Ambrose, Charles T

    2014-02-01

    The treatment of mild psychoneuroses in America began shifting in the 1950s from Freudian psychoanalysis to various forms of psychotherapy that do not delve into patient's subconscious. Some of the new approaches were termed cognitive, behavioural or cognitive behavioural therapy and in America were practised notably by Joseph Wolpe, Albert Ellis and Aaron T Beck. Modern psychiatric literature makes little mention of two prior innovators in this area - the French neurologist Jules Dejerine and his Boston disciple Joseph H Pratt. In the early 1900s, Dejerine treated patients at La Salpêtrière in Paris using techniques adopted subsequently by Pratt during the 1930s and employed by the trio some decades later. This paper revisits the early history of psychotherapy in America and includes a brief summary of Pratt's medical career.

  15. Pratt & Whitney ESCORT derivative for mars surface power

    NASA Astrophysics Data System (ADS)

    Feller, Gerald J.; Joyner, Russell

    1999-01-01

    The purpose of this paper is to address the applicability of a common reactor system design from the Pratt & Whitney ESCORT nuclear thermal rocket engine concept to support current NASA mars surface-based power requirements. The ESCORT is a bimodal engine capable of supporting a wide range of propulsive thermal and vehicle electrical power requirements. The ESCORT engine is powered by a fast-spectrum beryllium-reflected CERMET-fueled nuclear reactor. In addition to an expander cycle propulsive mode, the ESCORT is capable of operating in an electrical power mode. In this mode, the reactor is used to heat a mixture of helium and xenon to drive a closed-loop Brayton cycle in order to generate electrical energy. Recent Design Reference Mission requirements (DRM) from NASA Johnson Space Center and NASA Lewis Research Center studies in 1997 and 1998 have detailed upgraded requirements for potential mars transfer missions. The current NASA DRM requires a nuclear thermal propulsion system capable of delivering total mission requirements of 200170 N (45000 lbf) thrust and 50 kWe of spacecraft electrical power. Additionally, these requirements detailed a surface power system capable of providing approximately 160 kW of electrical energy over an approximate 10 year period within a given weight and volume envelope. Current NASA studies use a SP-100 reactor (0.8 MT) and a NERVA derivative (1.6 MT) as baseline systems. A mobile power cart of approximate dimensions 1.7 m×4.5 m×4.4 m has been conceptualized to transport the reactor power system on the Mars Surface. The 63.25 cm diameter and 80.25 cm height of the ESCORT and its 1.3 MT of weight fit well within the current weight and volume target range of the NASA DRM requirements. The modifications required to the ESCORT reactor system to support this upgraded electrical power requirements along with operation in the Martian atmospheric conditions are addressed in this paper. Sufficient excess reactivity and burnup capability

  16. 77 FR 23637 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-20

    ... stage high-pressure turbine (HPT) seal support, part number (P/N) 55K601 or P/N 50K532, installed. This proposed AD was prompted by 58 reports of cracked 1st stage HPT air seal rings, including 15 in-flight engine shutdowns. This proposed AD would require installation of a redesigned 1st stage HPT seal...

  17. 77 FR 57007 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-17

    ... Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY..., PW4152, PW4156A, PW4158, PW4164, PW4168, PW4168A, PW4460, and PW4462 turbofan engines. That AD currently... rotor disk assembly for certain affected engine models. We are issuing this AD to prevent failure of...

  18. 77 FR 42424 - Airworthiness Directives; Pratt & Whitney Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-19

    ... Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are... turbofan engines. That AD currently requires removing the 15th stage high-pressure compressor (HPC) disk... stage HPC disk, uncontained engine failure, and damage to the airplane. DATES: This AD is...

  19. 77 FR 67763 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-14

    ... by 16 reports of damaged or failed 3rd stage low-pressure turbine (LPT) duct segments. This AD requires removing from service certain part numbers (P/Ns) of 3rd stage LPT duct segments. We are issuing this AD to prevent failure of the 3rd stage LPT duct segments, which could lead to LPT rotor...

  20. 77 FR 2015 - Special Conditions: Pratt and Whitney Canada Model PW210S Turboshaft Engine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 33 Special Conditions: Pratt and Whitney Canada Model PW210S Turboshaft Engine Correction In rule document 2011-14113 appearing on pages 33981-33982 in the issue...

  1. Beyond the Comfort Zone: Betsy Diamant-Cohen--Enoch Pratt Free Library, Baltimore

    ERIC Educational Resources Information Center

    Library Journal, 2004

    2004-01-01

    What have librarians got to do with brain research? Much more than most librarians realize, says Betsy Diamant-Cohen, Children's Programming Specialist at the Enoch Pratt Free Library, Baltimore. Her original plan was to be a social worker, but it was suggested that she could be equally effective in improving lives as a librarian--while having a…

  2. 77 FR 16921 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ..., cleaning, and engine modifications to address coking in the No. 4 bearing compartment and in the oil.... FOR FURTHER INFORMATION CONTACT: James Gray, Aerospace Engineer, Engine & Propeller Directorate, FAA... inspections, cleaning, and engine modifications to address coking in the No. 4 bearing compartment and...

  3. 77 FR 26943 - Airworthiness Directives; Pratt & Whitney Canada Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-08

    ... Canada Turboprop Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule; request... series turboprop engines. This AD requires removal from service of certain part manufacturer approval... which will result in an engine in-flight shut down, possible uncontained engine failure, aircraft...

  4. 77 FR 54791 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-06

    ... Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY...'' and PW4000-100'' turbofan engines having a 1st stage high-pressure turbine (HPT) seal support, part..., including 15 in-flight engine shutdowns. This AD requires removal and replacement of the 1st stage HPT...

  5. 77 FR 12448 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-01

    ... the maintenance planning guide for main fuel pumps, including in the engine manual additional... perform the FMU modification using their normal maintenance program and shop procedures. ] We partially... maintenance program and shop procedures. We changed the AD to IBR the portion of the Hamilton Sundstrand...

  6. Babcock and Wilcox assessment of the Pratt and Whitney XNR2000

    NASA Technical Reports Server (NTRS)

    Westerman, Kurt O.; Scoles, Stephen W.; Jensen, R. R.; Rodes, J. R.; Ales, M. W.

    1993-01-01

    Babcock & Wilcox performed four subtasks related to the assessment of the Pratt & Whitney XNR2000 nuclear reactor as follows: (1) cermet fuel element fabricability assessment; (2) mechanical design review of the reactor system; (3) neutronic analysis review; and (4) safety assessment. The results of the mechanical and physics reviews have been integrated into the reactor design. The results of the fuel and safety assessments are presented.

  7. Combined string searching algorithm based on knuth-morris- pratt and boyer-moore algorithms

    NASA Astrophysics Data System (ADS)

    Tsarev, R. Yu; Chernigovskiy, A. S.; Tsareva, E. A.; Brezitskaya, V. V.; Nikiforov, A. Yu; Smirnov, N. A.

    2016-04-01

    The string searching task can be classified as a classic information processing task. Users either encounter the solution of this task while working with text processors or browsers, employing standard built-in tools, or this task is solved unseen by the users, while they are working with various computer programmes. Nowadays there are many algorithms for solving the string searching problem. The main criterion of these algorithms’ effectiveness is searching speed. The larger the shift of the pattern relative to the string in case of pattern and string characters’ mismatch is, the higher is the algorithm running speed. This article offers a combined algorithm, which has been developed on the basis of well-known Knuth-Morris-Pratt and Boyer-Moore string searching algorithms. These algorithms are based on two different basic principles of pattern matching. Knuth-Morris-Pratt algorithm is based upon forward pattern matching and Boyer-Moore is based upon backward pattern matching. Having united these two algorithms, the combined algorithm allows acquiring the larger shift in case of pattern and string characters’ mismatch. The article provides an example, which illustrates the results of Boyer-Moore and Knuth-Morris- Pratt algorithms and combined algorithm’s work and shows advantage of the latter in solving string searching problem.

  8. 76 FR 41430 - Airworthiness Directives; Pratt & Whitney Division (PW) PW4000 Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-14

    ... available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: James Gray, Aerospace... PW4ENG 73-150, or Engineering Change Number EC92KK322G, H, I, J, and K, as indicated with a (-3), or (-3A...-504, or PW4ENG 72-512, or PW4ENG 72- 572, or PW4ENG 72-588, or PW4ENG 73-150, or Engineering...

  9. Critical Digital Literacies: Following Feminist Composition Theories into Twenty-First Century Contact Zones

    ERIC Educational Resources Information Center

    Blackburn, Jessica B.

    2010-01-01

    This dissertation examines how the interests of feminist composition theory, digital media, and new literacies studies intersect within the research context of the first-year writing classroom. Specifically, this project examines what happens to the "contact zone" (Pratt 1991; Bizzell 1994) of first-year composition when we introduce digital…

  10. 76 FR 39795 - Special Conditions: Pratt and Whitney Canada Model PT6C-67E Turboshaft Engine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ... Whitney Canada Model PT6C-67E Turboshaft Engine AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... Whitney Canada (PWC) model PT6C-67E engines. The engine model will have a novel or unusual design feature... PT6C-67E turboshaft engines. If Pratt and Whitney Canada applies later for a change to the...

  11. Pratt and Whitney Rocketdyne Space Shuttle Main Engine Heritage Commemorative: Powerhead and Ducts, Test and Flight Operations

    NASA Technical Reports Server (NTRS)

    Cook, Jerry R.; Willis, Martha

    2009-01-01

    The videos (Powerhead and Ducts, Test and Flight Operations) review the Space Shuttle Main Engine (SSME) program from Pratt and Whitney Rocketdyne. They include highlights from the engine's development and lifecycle through the engine testing to the deployment in the space shuttle.

  12. Systems Engineering Processes at NASA/SR-71 Pratt and Whitney J58 Engine

    NASA Technical Reports Server (NTRS)

    Donastorg, Cristina

    2010-01-01

    This summer I was given several opportunities at NASA's Dryden Flight Research Center (DFRC). The first opportunity was given to me by a Senior Propulsion Engineer, Kurtt Kloesel, to work in a specialized engineering discipline. My task was to research the Pratt & Whitney J58 engine that was used on the SR-71 Blackbird. I entered the data I collected into engine modeling software programs in order to receive certain outputs, such as net thrust. I also had to take a "crash course" in propulsion in order to better understand the research I was performing. To facilitate my understanding of propulsion principals and formulas, I worked many problems out of thermodynamics and propulsion textbooks and entered the given values of various situations into the modeling software.

  13. Contact dermatitis

    MedlinePlus

    Dermatitis - contact; Allergic dermatitis; Dermatitis - allergic; Irritant contact dermatitis; Skin rash - contact dermatitis ... There are 2 types of contact dermatitis. Irritant dermatitis: This ... can be by contact with acids, alkaline materials such as soaps ...

  14. ESCORT: A Pratt & Whitney nuclear thermal propulsion and power system for manned mars missions

    NASA Astrophysics Data System (ADS)

    Feller, Gerald J.; Joyner, Russell

    1999-01-01

    The purpose of this paper is to describe the conceptual design of an upgrade to the Pratt & Whitney ESCORT nuclear thermal rocket engine. The ESCORT is a bimodal engine capable of supporting a wide range of vehicle propulsive and electrical power requirements. The ESCORT engine is powered by a fast-spectrum beryllium-reflected CERMET-fueled nuclear reactor. In propulsive mode, the reactor is used to heat hot hydrogen to approximately 2700 K which is expanded through a converging/diverging nozzle to generate thrust. Heat pickup in the nozzle and the radial beryllium reflectors is used to drive the turbomachinery in the ESCORT expander cycle. In electrical mode, the reactor is used to heat a mixture of helium and xenon to drive a closed-loop Brayton cycle in order to generate electrical energy. This closed loop system has the additional function of a decay heat removal system after the propulsive mode operation is discontinued. The original ESCORT design was capable of delivering 4448.2 N (1000 lbf) of thrust at a vacuum impulse level of approximately 900 s. Design Reference Mission requirements (DRM) from NASA Johnson Space Center and NASA Lewis Research Center studies in 1997 and 1998 have detailed upgraded requirements for potential manned Mars missions. The current NASA DRM requires a nuclear thermal propulsion system capable of delivering total mission requirements of 200170 N (45000 lbf) thrust and 50 kWe of spacecraft electrical power. This is met assuming three engines capable of each delivering 66723 N (15000 lbf) of vacuum thrust and 25 kWe of electrical power. The individual engine requirements were developed assuming three out of three engine reliability for propulsion and two out of three engine reliability for spacecraft electrical power. The approximate target vacuum impulse is 925 s. The Pratt & Whitney ESCORT concept was upgraded to meet these requirements. The hexagonal prismatic fuel elements were modified to address the uprated power requirements

  15. 76 FR 68660 - Airworthiness Directives; Pratt & Whitney Division (PW) PW4000 Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-07

    ... Aviation Administration 14 CFR Part 39 [Docket No. FAA-2011-0944; Directorate Identifier 2011-NE-11-AD] RIN... propose to adopt a new airworthiness directive (AD) for PW4000 series turbofan engines. This proposed AD... after the effective date of this proposed AD. This proposed AD was prompted by an engine overspeed...

  16. Hairy AdS solitons

    NASA Astrophysics Data System (ADS)

    Anabalón, Andrés; Astefanesei, Dumitru; Choque, David

    2016-11-01

    We construct exact hairy AdS soliton solutions in Einstein-dilaton gravity theory. We examine their thermodynamic properties and discuss the role of these solutions for the existence of first order phase transitions for hairy black holes. The negative energy density associated to hairy AdS solitons can be interpreted as the Casimir energy that is generated in the dual filed theory when the fermions are antiperiodic on the compact coordinate.

  17. Pacer Comet 4: Automated Jet Engine Testing of a TF33-P100 Pratt & Whitney Engine

    NASA Astrophysics Data System (ADS)

    Mason, Rex Bolding

    Pacer Comet 4 found its life out of necessity to replace an obsolescent Pacer Comet 3 engine test system at Tinker AFB in Oklahoma City, OK. Pacer Comet 3 (PC3) was created and installed in the early 1980's to test jet engines from a wide range of planes. PC3 had several problems from a maintenance standpoint: contractors designed and installed the system but the contract did not include the OEM data package. Without drawings or design knowledge, fixing the smallest of problems could turn into a multi-day project. In addition to high cost, as the OEM companies of proprietary parts went out of business, it became impossible to find a replacement for a failed part. These issues set the framework for the Pacer Comet 4 (PC4) system. PC4 was created as an organic AF and Department of Defense collaboration to fix the issues with PC3. PC4 provides the customer with a complete data package including multiple drawing sets and data sheets for all parts used, as well as design files for all PCBs created in house. PC4 has a standard to use commercially available off the shelf parts (COTS). The reason for this is sustainability in maintenance. If a part is to fail, it should be able to be purchased from any manufacturer that meets the specs of the original product. No proprietary parts are used, except as directed by the engine's OEM. This thesis will focus on the design and installation of the on-frame data acquisition PC4 system for the Pratt & Whitney TF33-P100A-QEC engine that is currently in use on the E3 Sentry. This thesis will show efficiency improvements for maintenance sustainability (70% cabling reduction) as well as discuss performance improvements in both test and production environments.

  18. Added Sugars

    MedlinePlus

    ... need sugar to function properly. Added sugars contribute zero nutrients but many added calories that can lead to extra pounds or even obesity, thereby reducing heart health. If you think of your daily calorie needs as a budget, you want to “spend” ...

  19. Value Added?

    ERIC Educational Resources Information Center

    UCLA IDEA, 2012

    2012-01-01

    Value added measures (VAM) uses changes in student test scores to determine how much "value" an individual teacher has "added" to student growth during the school year. Some policymakers, school districts, and educational advocates have applauded VAM as a straightforward measure of teacher effectiveness: the better a teacher,…

  20. 77 FR 11017 - Airworthiness Directives; Pratt & Whitney (PW) Models PW4074 and PW4077 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-24

    ... multiple shop findings of cracked 15th stage HPC disks. We issued that AD to prevent cracks from... from multiple shop findings of cracked 15th stage HPC disks. We are issuing this AD to prevent...

  1. 75 FR 55459 - Airworthiness Directives; Pratt & Whitney (PW) PW4000 Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-13

    ...) PW4000 Series Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule... amend 14 CFR part 39 with a proposed AD. The proposed AD applies to PW PW4000 series turbofan...

  2. 76 FR 47056 - Airworthiness Directives; Pratt & Whitney (PW) Models PW4074 and PW4077 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ... borescope inspection (BSI) or eddy current inspection (ECI) of the rim for cracks. This AD was prompted by... exceed 12,000 CSN on the effective date of this AD, perform a borescope inspection (BSI) or eddy...

  3. Design review and analysis for a Pratt and Whitney fluid-film bearing and seal testing rig

    NASA Astrophysics Data System (ADS)

    Childs, Dara W.

    1994-11-01

    A design review has been completed for a Pratt and Whitney (P&W)-designed fluid-film bearing and annular-seal test rig to be manufactured and installed at George C. Marshall Space Flight Center (MSFC). Issues covered in this study include: (1) the capacity requirements of the drive unit; (2) the capacity and configuration of the static loading system; (3) the capacity and configuration of the dynamic excitation system; (4) the capacity, configuration, and rotordynamic stability of a test bearing, support bearings, and shaft; and (5) the characteristics and configuration of the measurement transducers and data channels.

  4. Design review and analysis for a Pratt and Whitney fluid-film bearing and seal testing rig

    NASA Technical Reports Server (NTRS)

    Childs, Dara W.

    1994-01-01

    A design review has been completed for a Pratt and Whitney (P&W)-designed fluid-film bearing and annular-seal test rig to be manufactured and installed at George C. Marshall Space Flight Center (MSFC). Issues covered in this study include: (1) the capacity requirements of the drive unit; (2) the capacity and configuration of the static loading system; (3) the capacity and configuration of the dynamic excitation system; (4) the capacity, configuration, and rotordynamic stability of a test bearing, support bearings, and shaft; and (5) the characteristics and configuration of the measurement transducers and data channels.

  5. 78 FR 2331 - Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-11

    ... propeller shafts for cracks and removal from service if found cracked. This new AD requires the same actions... repetitive inspections. This AD was prompted by reports of two propeller shafts found cracked at time of inspection during maintenance. We are issuing this AD to detect propeller shaft cracks, which could...

  6. 76 FR 63571 - Airworthiness Directives; Eclipse Aerospace, Inc. Airplanes Equipped With Pratt & Whitney Canada...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-13

    ... Part 39 [Docket No. FAA-2011-0199; Directorate Identifier 2011-CE-005-AD] RIN 2120-AA64 Airworthiness...: We propose to revise an existing airworthiness directive (AD) that applies to all Eclipse Aerospace.... The existing AD currently requires incorporating an operating limitation of a maximum...

  7. 78 FR 20503 - Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-05

    .... This proposed AD was prompted by reports of fractures of the 1st stage power turbine (PT) blade. This... proposing this AD to prevent fracture of the 1st stage PT blade, possible engine fire, and damage to the..., dated March 8, 2013. (d) Reason This AD was prompted by reports of fractures of the 1st stage PT...

  8. Adding Value.

    ERIC Educational Resources Information Center

    Orsini, Larry L.; Hudack, Lawrence R.; Zekan, Donald L.

    1999-01-01

    The value-added statement (VAS), relatively unknown in the United States, is used in financial reports by many European companies. Saint Bonaventure University (New York) has adapted a VAS to make it appropriate for not-for-profit universities by identifying stakeholder groups (students, faculty, administrators/support personnel, creditors, the…

  9. 75 FR 78881 - Airworthiness Directives; Pratt & Whitney PW4000 Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-17

    ... PW4000 Series Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule... turbofan engines. This AD requires initial and repetitive borescope inspections (BSI) or fluorescent.... We are issuing this AD to prevent failure of the HPC 10th stage disk, uncontained engine failure,...

  10. 77 FR 11421 - Airworthiness Directives; Pratt & Whitney Canada, Auxiliary Power Units

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-27

    ... separation of the rear gas generator case and release of high energy debris. This proposed AD would require... proposing this AD to prevent separation of the rear gas generator case and release of high energy debris... which have resulted in the separation of the rear gas generator case, exhaust duct support, the...

  11. 77 FR 60288 - Airworthiness Directives; Pratt & Whitney (P&W) Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    .... This AD was prompted by reports of 3rd and 4th stage vane fractures in the low-pressure turbine (LPT... prevent 3rd and 4th stage vane fractures in the LPT, damage to the LPT rotor, uncontained engine failure...) Unsafe Condition This AD was prompted by reports of 3rd and 4th stage vane fractures in the...

  12. 78 FR 49109 - Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ..., and PW127M turboprop engines. This AD was prompted by reports of fractures of the first-stage power.... We are issuing this AD to prevent fracture of the first-stage PT blade, possible engine fire, and... report revealed that the fracture of one low-pressure turbine (LPT) blade near the platform was...

  13. 76 FR 72130 - Airworthiness Directives; Pratt & Whitney JT9D Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ... revisions to the Airworthiness Limitations Section (ALS) of the manufacturer's Instructions for Continued... life-limited parts. This proposed AD would require additional revisions to the JT9D series engines ALS... all PW JT9D series turbofan engines. That AD requires revisions to the ALS of the manufacturer's...

  14. Pratt & Whitney Two Dimensional HSR Nozzle Test in the NASA Lewis 9- By 15- Foot Low Speed Wind Tunnel: Aerodynamic Results

    NASA Technical Reports Server (NTRS)

    Wolter, John D.; Jones, Christopher W.

    1999-01-01

    This paper discusses a test that was conducted jointly by Pratt & Whitney Aircraft Engines and NASA Lewis Research Center. The test was conducted in NASA's 9- by 15-Foot Low Speed Wind Tunnel (9x15 LSWT). The test setup, methods, and aerodynamic results of this test are discussed. Acoustical results are discussed in a separate paper by J. Bridges and J. Marino.

  15. 78 FR 11563 - Airworthiness Directives; Pratt & Whitney Canada Corp Turboshaft Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-19

    ... root cause for the PT baffle displacement and the resultant PT disk damage was due to the failure of... estimate that it will take about six hours per engine to comply with this AD. The average labor rate is...

  16. 75 FR 67253 - Airworthiness Directives; Pratt & Whitney (PW) Models PW4074 and PW4077 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... effective date of this AD using a drawdown plan that includes a borescope inspection (BSI) or eddy current... installed in the engine and exceed 12,000 CSN, perform a borescope inspection (BSI) or eddy...

  17. Contact Dermatitis

    MedlinePlus

    ... Us Media contacts Advertising contacts AAD logo Advertising, marketing and sponsorships Legal notice Copyright © 2017 American Academy ... prohibited without prior written permission. AAD logo Advertising, marketing and sponsorships Legal notice Copyright © 2017 American Academy ...

  18. Telocyte's contacts.

    PubMed

    Faussone-Pellegrini, Maria-Simonetta; Gherghiceanu, Mihaela

    2016-07-01

    Telocytes (TC) are an interstitial cell type located in the connective tissue of many organs of humans and laboratory mammals. By means of homocellular contacts, TC build a scaffold whose meshes integrity and continuity are guaranteed by those contacts having a mechanical function; those contacts acting as sites of intercellular communication allow exchanging information and spreading signals. Heterocellular contacts between TC and a great variety of cell types give origin to mixed networks. TC, by means of all these types of contacts, their interaction with the extracellular matrix and their vicinity to nerve endings, are part of an integrated system playing tissue/organ-specific roles.

  19. 77 FR 56794 - Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-14

    ... after receipt. FOR FURTHER INFORMATION CONTACT: James Lawrence, Aerospace Engineer, Engine Certification... for cracks in the inner bore of the propeller shafts identified by S/N in Tables 1 and 2 of that ASB... James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate,...

  20. 78 FR 64421 - Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-29

    ... several incidents of compressor turbine (CT) blade failure, including two fatalities, resulting in power... borescope inspections (BSIs) of CT blades, and the removal from service of blades that fail inspection. We are proposing this AD to prevent failure of CT blades, which could lead to damage to the engine or...

  1. 75 FR 71351 - Airworthiness Directives; Pratt & Whitney PW4000 Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-23

    ... removals, and one report of a test cell event from a repaired tube that cracked. We are issuing this AD to prevent cracking of No. 3 bearing oil pressure tubes, which could result in internal oil fire, failure of..., one report of a test cell event, and seven reports since 2007, of repaired No. 3 bearing oil...

  2. 77 FR 57001 - Airworthiness Directives; Pratt & Whitney Canada, Auxiliary Power Units

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-17

    ... by several events of high-pressure turbine blade fracture leading to separation of the rear gas generator case and release of high energy debris. We are issuing this AD to prevent separation of the rear... (HPT) blade fracture, some of which have resulted in the separation of the rear gas generator...

  3. 77 FR 12755 - Airworthiness Directives; Pratt & Whitney (PW) Division Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ... turbofan engines. This proposed AD was prompted by reports of 3rd and 4th stage vane fractures in the low pressure turbine (LPT) of certain PW4000-94'' and PW4000-100'' turbofan engines. These fractures caused an... to prevent 3rd and 4th stage vane fractures in the LPT, which could damage the LPT rotor and lead...

  4. Orientifolded locally AdS3 geometries

    NASA Astrophysics Data System (ADS)

    Loran, F.; Sheikh-Jabbari, M. M.

    2011-01-01

    Continuing the analysis of [Loran F and Sheikh-Jabbari M M 2010 Phys. Lett. B 693 184-7], we classify all locally AdS3 stationary axi-symmetric unorientable solutions to AdS3 Einstein gravity and show that they are obtained by applying certain orientifold projection on AdS3, BTZ or AdS3 self-dual orbifold, respectively, O-AdS3, O-BTZ and O-SDO geometries. Depending on the orientifold fixed surface, the O-surface, which is either a space-like 2D plane or a cylinder, or a light-like 2D plane or a cylinder, one can distinguish four distinct cases. For the space-like orientifold plane or cylinder cases, these geometries solve AdS3 Einstein equations and are hence locally AdS3 everywhere except at the O-surface, where there is a delta-function source. For the light-like cases, the geometry is a solution to Einstein equations even at the O-surface. We discuss the causal structure for static, extremal and general rotating O-BTZ and O-SDO cases as well as the geodesic motion on these geometries. We also discuss orientifolding Poincaré patch AdS3 and AdS2 geometries as a way to geodesic completion of these spaces and comment on the 2D CFT dual to the O-geometries.

  5. Warped AdS3 black holes

    NASA Astrophysics Data System (ADS)

    Anninos, Dionysios; Li, Wei; Padi, Megha; Song, Wei; Strominger, Andrew

    2009-03-01

    Three dimensional topologically massive gravity (TMG) with a negative cosmological constant -l-2 and positive Newton constant G admits an AdS3 vacuum solution for any value of the graviton mass μ. These are all known to be perturbatively unstable except at the recently explored chiral point μl = 1. However we show herein that for every value of μl ≠ 3 there are two other (potentially stable) vacuum solutions given by SL(2,Bbb R) × U(1)-invariant warped AdS3 geometries, with a timelike or spacelike U(1) isometry. Critical behavior occurs at μl = 3, where the warping transitions from a stretching to a squashing, and there are a pair of warped solutions with a null U(1) isometry. For μl > 3, there are known warped black hole solutions which are asymptotic to warped AdS3. We show that these black holes are discrete quotients of warped AdS3 just as BTZ black holes are discrete quotients of ordinary AdS3. Moreover new solutions of this type, relevant to any theory with warped AdS3 solutions, are exhibited. Finally we note that the black hole thermodynamics is consistent with the hypothesis that, for μl > 3, the warped AdS3 ground state of TMG is holographically dual to a 2D boundary CFT with central charges c_R-formula and c_L-formula.

  6. Warped AdS3 black holes

    NASA Astrophysics Data System (ADS)

    Song, Wei; Anninos, Dionysios; Li, Wei; Padi, Megha; Strominger, Andrew

    2009-03-01

    Three dimensional topologically massive gravity (TMG) with a negative cosmological constant -ell-2 and positive Newton constant G admits an AdS3 vacuum solution for any value of the graviton mass μ. These are all known to be perturbatively unstable except at the recently explored chiral point μell = 1. However we show herein that for every value of μell ≠ 3 there are two other (potentially stable) vacuum solutions given by SL(2,Bbb R) × U(1)-invariant warped AdS3 geometries, with a timelike or spacelike U(1) isometry. Critical behavior occurs at μell = 3, where the warping transitions from a stretching to a squashing, and there are a pair of warped solutions with a null U(1) isometry. For μell > 3, there are known warped black hole solutions which are asymptotic to warped AdS3. We show that these black holes are discrete quotients of warped AdS3 just as BTZ black holes are discrete quotients of ordinary AdS3. Moreover new solutions of this type, relevant to any theory with warped AdS3 solutions, are exhibited. Finally we note that the black hole thermodynamics is consistent with the hypothesis that, for μell > 3, the warped AdS3 ground state of TMG is holographically dual to a 2D boundary CFT with central charges c_R-formula and c_L-formula.

  7. Development of a cAdVax-Based Bivalent Ebola Virus Vaccine that Induces Immune Responses Against Both the Sudan and Zaire Species of Ebola Virus, Journal of Virology

    DTIC Science & Technology

    2005-12-27

    Society for Microbiology. All Rights Reserved. Development of a cAdVax-Based Bivalent Ebola Virus Vaccine That Induces Immune Responses against both the...B. Deitz,1 Hong Yu,3 Benjamin M. Swain,1 Kevin M. Moore,1 William D. Pratt,2 Mary Kate Hart,2 and John Y. Dong1,3* Division of Biodefense Vaccines ...currently no vaccines or effective treatments. While lethal human outbreaks have so far been restricted to sub-Saharan Africa, the potential exploitation

  8. Contact hysteroscopy.

    PubMed

    Baggish, M S; Barbot, J

    1983-06-01

    In 1907 innovations in optics and illumination made by Maximilian Nitze were applied to hysteroscopy by Charles David, who wrote a treatise of hysteroscopy. David improved illumination by placing an electric incandescent bulb at the intrauterine end of his endoscope and also sealed the distal end of the tube with a piece of glass. The history of the contact endoscope that the authors personally used is connected to the invention by Vulmiere (1952) of a revolutionary illumination process in endoscopy--the "cold light" process. The components of cold light consist of a powerful external light source that is transmitted via a special optical guide into the endometrial cavity. The 1st application of his principle (1963) was an optical trochar contained in a metallic sheath. This simple endoscope was perfected, and in 1973 Barbot and Parent, in France, began to use it to examine the uterine cavity. Discussion focuses on methods, instrumentation, method for examination (grasping the instrument, setup, light source, anesthesia, dilatation, technique, and normal endometrium); cervical neoplasia; nonneoplastic lesions of the endometrium (endometrial polyp, submucous myoma, endometrial hyperplasia); intrauterine device localization; neoplastic lesions of the endometrium; precursors (adenocarcinoma); hysteroscopy in pregnancy (embryoscopy, hydatidiform mole, postpartum hemorrhage, incomplete abortion, spontaneous abortion, induced abortions, and amnioscopy); and examinations of children and infants. The contact endoscope must make light contact with the structure to be viewed. The principles of contact endoscopy depend on an interpretation of color, contour, vascular pattern, and a sense of touch. These are computed together and a diagnosis is made on the basis of previously learned clinical pathologic correlations. The contact endoscope is composed of 3 parts: an optical guide; a cylindric chamber that collects and traps ambient light; and a magnifying eyepiece. The phase of

  9. Segmented strings in AdS 3

    NASA Astrophysics Data System (ADS)

    Callebaut, Nele; Gubser, Steven S.; Samberg, Andreas; Toldo, Chiara

    2015-11-01

    We study segmented strings in flat space and in AdS 3. In flat space, these well known classical motions describe strings which at any instant of time are piecewise linear. In AdS 3, the worldsheet is composed of faces each of which is a region bounded by null geodesics in an AdS 2 subspace of AdS 3. The time evolution can be described by specifying the null geodesic motion of kinks in the string at which two segments are joined. The outcome of collisions of kinks on the worldsheet can be worked out essentially using considerations of causality. We study several examples of closed segmented strings in AdS 3 and find an unexpected quasi-periodic behavior. We also work out a WKB analysis of quantum states of yo-yo strings in AdS 5 and find a logarithmic term reminiscent of the logarithmic twist of string states on the leading Regge trajectory.

  10. Geohydrology and saline ground-water discharge to the South Fork Ninnescah River in Pratt and Kingman Counties, south-central Kansas

    USGS Publications Warehouse

    Gillespie, Joe B.; Hargadine, G.D.

    1994-01-01

    Saline ground water discharges to the South Fork Ninnescah River in Pratt and Kingman Counties from the adjacent alluvial aquifer. Electromagnetic terrain surveys in this area indicated that the saline ground water is entering the river in intermittent reaches along the channel. The chloride concentration in the river near Murdock exceeds 250 milligrams per liter 75 percent of the time. During base flow in November 1988, stream discharge increased 67 cubic feet per second, and the chloride concentration increased 360 milligrams per liter from Pratt to the Pratt-Kingman County line. The chloride load to the river along this reach was 82 tons per day. The source of saline water probably is dissolution of salt in the Permian rocks, about 600 feet below land surface. Subsequent subsidence and collapse of Permian rocks into salt-dissolution cavities probably has caused fracturing in overlying Permian rocks. Brine moves upward through the Permian rocks and discharges into the alluvial aquifer. The brine discharge to the alluvium is about 0.7 cubic foot per second. In the area of major saline-water discharge to the river, the fluid-potential levels in the Permian rocks are higher than fluid-potential levels in the alluvial aquifer. Several methods for reducing the saline ground-water discharge to the South Fork Ninnescah River have been considered. The most effective of these methods appears to be interception of brine flow in the Permian rocks by pumping of relief wells. Brine could be disposed by injection into deeper formations, by storage in evaporation reservoirs, or by desalinization.

  11. 76 FR 16526 - Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, -217C, and -219 Series Turbofan...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-24

    ... with bolts and nuts made of Tinidur material. This new AD requires the same torque inspection, blade... longer bolts made of Tinidur material. This AD also requires installation of crushable sleeve spacers on the bolts. This AD was prompted by nine reports of failure of Tinidur material LPT-to-exhaust...

  12. Types of Contact Lenses

    MedlinePlus

    ... Consumer Devices Consumer Products Contact Lenses Types of Contact Lenses Share Tweet Linkedin Pin it More sharing ... Orthokeratology (Ortho-K) Decorative (Plano) Contact Lenses Soft Contact Lenses Soft contact lenses are made of soft, ...

  13. Prioritized Contact Transport Stream

    NASA Technical Reports Server (NTRS)

    Hunt, Walter Lee, Jr. (Inventor)

    2015-01-01

    A detection process, contact recognition process, classification process, and identification process are applied to raw sensor data to produce an identified contact record set containing one or more identified contact records. A prioritization process is applied to the identified contact record set to assign a contact priority to each contact record in the identified contact record set. Data are removed from the contact records in the identified contact record set based on the contact priorities assigned to those contact records. A first contact stream is produced from the resulting contact records. The first contact stream is streamed in a contact transport stream. The contact transport stream may include and stream additional contact streams. The contact transport stream may be varied dynamically over time based on parameters such as available bandwidth, contact priority, presence/absence of contacts, system state, and configuration parameters.

  14. Pratt and Whitney Activities

    NASA Technical Reports Server (NTRS)

    Syed, Saadat A.

    1991-01-01

    An example of Computational Fluid Dynamics (CFD) application in the seal area is described. This effort consisted of optimizing specific seals in the Space Shuttle Main Engine Alternate Turbopump Development (SSME ATD) and resulted in design of a seal tested which demonstrated 30 percent lower leakage than the standard design at the same clearance. This example shows the potential of identifying seal geometry parameters which reduce internal flow leakages detrimental to component and turbopump efficiencies. This information can than be used to develop an analytical design procedure for controlling leakage in any given application or environment.

  15. AdS duals of matrix strings

    NASA Astrophysics Data System (ADS)

    Morales, Jose F.; Samtleben, Henning

    2003-06-01

    We review recent work on the holographic duals of type II and heterotic matrix string theories described by warped AdS3 supergravities. In particular, we compute the spectra of Kaluza-Klein primaries for type I, II supergravities on warped AdS3 × S7 and match them with the primary operators in the dual two-dimensional gauge theories. The presence of non-trivial warp factors and dilaton profiles requires a modification of the familiar dictionary between masses and 'scaling' dimensions of fields and operators. We present these modifications for the general case of domain wall/QFT correspondences between supergravities on warped AdSd+1 × Sq geometries and super Yang-Mills theories with 16 supercharges.

  16. 76 FR 41144 - Airworthiness Directives; Pratt & Whitney Corp. (PW) JT9D-7R4H1 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ... life limits, and establishes a new, lower life-limit for these parts. This proposed AD was prompted by...-2011-0731; Directorate Identifier 2010-NE-39-AD'' at the beginning of your comments. We specifically... operating metal ] temperatures impose a greater low-cycle fatigue life debit for each operating...

  17. EDITORIAL: Close contact Close contact

    NASA Astrophysics Data System (ADS)

    Demming, Anna

    2010-07-01

    The development of scanning probe techniques, such as scanning tunnelling microscopy [1], has often been touted as the catalyst for the surge in activity and progress in nanoscale science and technology. Images of nanoscale structural detail have served as an invaluable investigative resource and continue to fascinate with the fantastical reality of an intricate nether world existing all around us, but hidden from view of the naked eye by a disparity in scale. As is so often the case, the invention of the scanning tunnelling microscope heralded far more than just a useful new apparatus, it demonstrated the scope for exploiting the subtleties of electronic contact. The shrinking of electronic devices has been a driving force for research into molecular electronics, in which an understanding of the nature of electronic contact at junctions is crucial. In response, the number of experimental techniques in molecular electronics has increased rapidly in recent years. Scanning tunnelling microscopes have been used to study electron transfer through molecular films on a conducting substrate, and the need to monitor the contact force of scanning tunnelling electrodes led to the use of atomic force microscopy probes coated in a conducting layer as studied by Cui and colleagues in Arizona [2]. In this issue a collaboration of researchers at Delft University and Leiden University in the Netherlands report a new device architecture for the independent mechanical and electrostatic tuning of nanoscale charge transport, which will enable thorough studies of molecular transport in the future [3]. Scanning probes can also be used to pattern surfaces, such as through spatially-localized Suzuki and Heck reactions in chemical scanning probe lithography. Mechanistic aspects of spatially confined Suzuki and Heck chemistry are also reported in this issue by researchers in Oxford [4]. All these developments in molecular electronics fabrication and characterization provide alternative

  18. Strings on AdS wormholes and nonsingular black holes

    NASA Astrophysics Data System (ADS)

    Lü, H.; Vázquez-Poritz, Justin F.; Zhang, Zhibai

    2015-01-01

    Certain AdS black holes in the STU model can be conformally scaled to wormhole and black hole backgrounds which have two asymptotically AdS regions and are completely free of curvature singularities. While there is a delta-function source for the dilaton, classical string probes are not sensitive to this singularity. According to the AdS/CFT correspondence, the dual field theory lives on the union of the disjoint boundaries. For the wormhole background, causal contact exists between the two boundaries and the structure of certain correlation functions is indicative of an interacting phase for which there is a coupling between the degrees of freedom living at each boundary. The nonsingular black hole describes an entangled state in two non-interacting identical conformal field theories. By studying the behavior of open strings on these backgrounds, we extract a number of features of the ‘quarks’ and ‘anti-quarks’ that live in the field theories. In the interacting phase, we find that there is a maximum speed with which the quarks can move without losing energy, beyond which energy is transferred from a quark in one field theory to a quark in the other. We also compute the rate at which moving quarks within entangled states lose energy to the two surrounding plasmas. While a quark-antiquark pair within a single field theory exhibits Coulomb interaction for small separation, a quark in one field theory exhibits spring-like confinement with an anti-quark in the other field theory. For the entangled states, we study how the quark-antiquark screening length depends on temperature and chemical potential.

  19. Application of fibrin sealant at the urethrovesical anastomosis in robotic assisted radical prostatectomy: does it enable earlier Foley catheter and Jackson-Pratt drain removal?

    PubMed

    Flury, Sarah C; Starnes, Danielle N; Steers, William D

    2008-01-01

    Leakage at the urethrovesical anastomosis in the post-operative period can result in morbidity including ileus. We examined the effectiveness of using a fibrin sealant at the anastomosis to limit urine leakage thereby facilitating earlier Jackson-Pratt drain and Foley catheter removal following robotic assisted laparoscopic prostatectomy (RALRP). Forty consecutive patients underwent RALRP by one surgeon at our institution. The first 20 patients underwent standard operation and served as the control group. The subsequent 20 patients underwent the same operation with addition of fibrin sealant following a running absorbable sutured urethrovesical anastomosis. The two groups were compared for age (60.5 vs. 58.2 years), pre-operative PSA (5.23 vs. 4.71), Gleason score (6.3 vs. 6.5), stage at resection, and prostate size at resection (51.7 vs. 47.7 g). Wilcoxon rank sum test determined no statistically significant differences in the groups. Patients in the fibrin sealant group had 1.3 versus 2.1 days with a Jackson-Pratt drain, 9.75 versus 12.1 days with a catheter, and an average of 38.6 versus 63.2 cc of drainage per shift. Catheters were removed when a cystogram demonstrated no extravasation of contrast. Two patients in the control group and no patients in the fibrin sealant group had large-volume leakage and ileus post-operatively. In patients undergoing RALRP, application of fibrin sealant at the urethrovesical anastomosis appears to facilitate sealing, thereby allowing earlier removal of the JP drain, by 0.8 days, and the Foley catheter, by 2.35 days, than in controls. No patients in the fibrin sealant group suffered post-operative ileus. This adjunct may be especially useful early in the learning process to reduce morbidity.

  20. An AdS Crunch in Supergravity

    NASA Astrophysics Data System (ADS)

    Hertog, Thomas

    2004-12-01

    We review some properties of N=8 gauged supergravity in four dimensions with modified, but AdS invariant boundary conditions on the m2 = -2 scalars. There is a one-parameter class of asymptotic conditions on these fields and the metric components, for which the full AdS symmetry group is preserved. The generators of the asymptotic symmetries are finite, but acquire a contribution from the scalar fields. For a large class of such boundary conditions, we find there exist black holes with scalar hair that are specified by a single conserved charge. Since Schwarschild-AdS is a solution too for all boundary conditions, this provides an example of black hole non-uniqueness. We also show there exist solutions where smooth initial data evolve to a big crunch singularity. This opens up the possibility of using the dual conformal field theory to obtain a fully quantum description of the cosmological singularity, and we report on a preliminary study of this.

  1. Allergic Contact Dermatitis

    PubMed Central

    Nelson, Jenny L.

    2010-01-01

    Epicutaneous patch testing is the gold standard method for the diagnosis of allergic contact dermatitis. Despite this knowledge, many clinical dermatologists do not offer patch testing in their offices or offer testing with only a limited number of allergens. Introduced in 1995, the Thin-Layer Rapid Use Epicutaneous Test originally contained 23 allergens and one control. In 2007, five additional allergens were added. This United States Food and Drug Administration-approved patch testing system made patch testing more convenient, and after its introduction, more dermatologists offered patch testing services. However, the number of allergens in the Thin-Layer Rapid Use Epicutaneous Test remains relatively low. Every two years, the North American Contact Dermatitis Group collects and reports the data from patch testing among its members to a standardized series of allergens. In 2005-2006, the Group used a series of 65 allergens. Of the top 30 allergens reported in 2005-2006, 10 were not included in the Thin-Layer Rapid Use Epicutaneous Test. Knowledge of and testing for additional allergens such as these may increase patch testing yield. PMID:20967194

  2. Contact Formation (Hg, CD)Te

    DTIC Science & Technology

    1989-12-01

    AD-A21 7 088 0 a CONTACT FORMATION ON (HG, CD )TE FINAL REPORT W.A. BECK AND G.D. DAVIS V C ELECTE , I DECEMBER 1989 JAN22 1990 U.S. ARMY RESEARCH...27709-2211 I N I 11. TITLE (Include Security Clasification) Contact Formation on (Hg, CD )Te (u) 12. PERSONAL AUTHOR(S) W.A. Beck and G.D. Davis 13a...whereas the 1/f noise of the Au contacts originated at th i/" Cd )Te interface or in the underlying (Hg, Cd )Te, the 1/f noise of the Al contacts orig.L

  3. 76 FR 13078 - Airworthiness Directives; Eclipse Aerospace, Inc. Model EA500 Airplanes Equipped With a Pratt and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-10

    ... carbon buildup on the static vane, which could result in engine surges. Engine surges may result in a... issued that AD to prevent hard carbon buildup on the static vane, which could result in engine surges... build up blocking the static vanes has continued to occur at 37,000 feet altitude and lower. Six...

  4. 75 FR 38052 - Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, -217C, and -219 Series Turbofan...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ... and nuts made of Tinidur material. This proposed AD would require the same actions but would require replacement of the LPT-to-exhaust case bolts and nuts with longer bolts made of Tinidur material, with nuts made of Tinidur material, and installation of crushable sleeve spacers on the bolts. This proposed...

  5. 75 FR 14377 - Airworthiness Directives; Pratt & Whitney (PW) Model PW2037, PW2037(M), and PW2040 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ... removing erosion damage on fan blades with cutback leading edges and restoring the leading edge contour. This proposed AD results from reports from PW that fan blade leading edge erosion can result in a fan... receipt. Discussion We have received reports from PW of leading edge erosion on PW2000 fan blades (LPC...

  6. AdS3: the NHEK generation

    NASA Astrophysics Data System (ADS)

    Bena, Iosif; Heurtier, Lucien; Puhm, Andrea

    2016-05-01

    It was argued in [1] that the five-dimensional near-horizon extremal Kerr (NHEK) geometry can be embedded in String Theory as the infrared region of an infinite family of non-supersymmetric geometries that have D1, D5, momentum and KK monopole charges. We show that there exists a method to embed these geometries into asymptotically- {AdS}_3× {S}^3/{{Z}}_N solutions, and hence to obtain infinite families of flows whose infrared is NHEK. This indicates that the CFT dual to the NHEK geometry is the IR fixed point of a Renormalization Group flow from a known local UV CFT and opens the door to its explicit construction.

  7. AdS2 holographic dictionary

    NASA Astrophysics Data System (ADS)

    Cvetič, Mirjam; Papadimitriou, Ioannis

    2016-12-01

    We construct the holographic dictionary for both running and constant dilaton solutions of the two dimensional Einstein-Maxwell-Dilaton theory that is obtained by a circle reduction from Einstein-Hilbert gravity with negative cosmological constant in three dimensions. This specific model ensures that the dual theory has a well defined ultraviolet completion in terms of a two dimensional conformal field theory, but our results apply qualitatively to a wider class of two dimensional dilaton gravity theories. For each type of solutions we perform holographic renormalization, compute the exact renormalized one-point functions in the presence of arbitrary sources, and derive the asymptotic symmetries and the corresponding conserved charges. In both cases we find that the scalar operator dual to the dilaton plays a crucial role in the description of the dynamics. Its source gives rise to a matter conformal anomaly for the running dilaton solutions, while its expectation value is the only non trivial observable for constant dilaton solutions. The role of this operator has been largely overlooked in the literature. We further show that the only non trivial conserved charges for running dilaton solutions are the mass and the electric charge, while for constant dilaton solutions only the electric charge is non zero. However, by uplifting the solutions to three dimensions we show that constant dilaton solutions can support non trivial extended symmetry algebras, including the one found by Compère, Song and Strominger [1], in agreement with the results of Castro and Song [2]. Finally, we demonstrate that any solution of this specific dilaton gravity model can be uplifted to a family of asymptotically AdS2 × S 2 or conformally AdS2 × S 2 solutions of the STU model in four dimensions, including non extremal black holes. The four dimensional solutions obtained by uplifting the running dilaton solutions coincide with the so called `subtracted geometries', while those obtained

  8. Contact Lens Risks

    MedlinePlus

    ... Health and Consumer Devices Consumer Products Contact Lenses Contact Lens Risks Share Tweet Linkedin Pin it More ... redness blurred vision swelling pain Serious Hazards of Contact Lenses Symptoms of eye irritation can indicate a ...

  9. Contact Lens Care

    MedlinePlus

    ... For Consumers Consumer Information by Audience For Women Contact Lens Care Share Tweet Linkedin Pin it More ... 1088, www.fda.gov/medwatch Learn More about Contact Lens Care Other Tips on Contact Lenses Decorative ...

  10. Contact Lenses for Vision Correction

    MedlinePlus

    ... Ophthalmologist Patient Stories Español Eye Health / Glasses & Contacts Contact Lenses Sections Contact Lenses for Vision Correction Proper ... to Know About Contact Lenses Colored Contact Lenses Contact Lenses for Vision Correction Written by: Kierstan Boyd ...

  11. AD(H)D.

    PubMed

    Harrison, Christopher; Charles, Janice; Britt, Helena

    2008-06-01

    The BEACH program (Bettering the Evaluation and Care of Health) shows that management of attention deficit (hyperactivity) disorder (AD(H)D) was rare in general practice, occurring only six times per 1,000 encounters with children aged 5-17 years, between April 2000 and December 2007. This suggests that general practitioners manage AD(H)D about 46,000 times for this age group nationally each year.

  12. ADS pilot program Plan

    NASA Technical Reports Server (NTRS)

    Clauson, J.; Heuser, J.

    1981-01-01

    The Applications Data Service (ADS) is a system based on an electronic data communications network which will permit scientists to share the data stored in data bases at universities and at government and private installations. It is designed to allow users to readily locate and access high quality, timely data from multiple sources. The ADS Pilot program objectives and the current plans for accomplishing those objectives are described.

  13. Specific Contact Resistance Measurements of Ohmic Contacts to Diamond

    DTIC Science & Technology

    1991-01-01

    AD-A262 818 a.vi tm te (11o ckiaa AGENCY USE CNLY re.j. b"IAI 2 REPORT DATS 3 i4 ý’ * : ..... .. February 1993 l , qf-r 4 T71 a AND SUBT’LE. SPECIFIC...rectify rnq and :1 i diamondi tl- ’o *been reported in the- literature 1-I paper measurements, of the specitic conatact inccc o.f ohmic ln tacts to...conducting layer. The contact resistance in these struc- tures is analyzed using the transmission line model [15. The primary drawback to

  14. Contact dermatitis caused by preservatives.

    PubMed

    Yim, Elizabeth; Baquerizo Nole, Katherine L; Tosti, Antonella

    2014-01-01

    Preservatives are biocidal chemicals added to food, cosmetics, and industrial products to prevent the growth of microorganisms. They are usually nontoxic and inexpensive and have a long shelf life. Unfortunately, they commonly cause contact dermatitis. This article reviews the most important classes of preservatives physicians are most likely to encounter in their daily practice, specifically isothiazolinones, formaldehyde and formaldehyde-releasers, iodopropynyl butylcarbamate, methyldibromoglutaronitrile, and parabens. For each preservative mentioned, the prevalence of sensitization, clinical presentation of contact dermatitis, patch testing concentrations, cross reactions, and related legislation will be discussed. Mandatory labeling of preservatives is required in some countries, but not required in others. Until policies are made, physicians and patients must be proactive in identifying potential sensitizers and removing their use. We hope that this article will serve as a guide for policy makers in creating legislation and future regulations on the use and concentration of certain preservatives in cosmetics and industrial products.

  15. Contact Us about Asbestos

    EPA Pesticide Factsheets

    How to contact EPA for more information on asbestos, including state and regional contacts, EPA’s Asbestos Abatement/Management Ombudsman and the Toxic Substances Control Act (TSCA) Assistance Information Service (TSCA Hotline).

  16. Colored Contact Lens Dangers

    MedlinePlus

    ... Halloween Hazard: The Hidden Dangers of Buying Decorative Contact Lenses Without a Prescription Sep. 26, 2013 It ... the truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager Blinded In One Eye By ...

  17. Contact sensitization to Compositae mix in children.

    PubMed

    Belloni Fortina, Anna; Romano, Ilaria; Peserico, Andrea

    2005-11-01

    The prevalence of contact sensitization to Compositae mix was investigated in 641 consecutive children. Seventeen children (12 with atopic dermatitis) tested positive for Compositae mix. We suggest adding Compositae mix to a pediatric screening series when investigating airborne dermatitis in children with atopic dermatitis.

  18. Adding and Deleting Images

    EPA Pesticide Factsheets

    Images are added via the Drupal WebCMS Editor. Once an image is uploaded onto a page, it is available via the Library and your files. You can edit the metadata, delete the image permanently, and/or replace images on the Files tab.

  19. What Value "Value Added"?

    ERIC Educational Resources Information Center

    Richards, Andrew

    2015-01-01

    Two quantitative measures of school performance are currently used, the average points score (APS) at Key Stage 2 and value-added (VA), which measures the rate of academic improvement between Key Stage 1 and 2. These figures are used by parents and the Office for Standards in Education to make judgements and comparisons. However, simple…

  20. Contact Lenses on Submarines

    DTIC Science & Technology

    2014-09-26

    NAVAL SUBMARINE MEDICAL RESEARCH LABORATORY SUBMARINE BASE, GROTON, CONN. REPORT NUMBER 1048 CONTACT LENSES ON SUBMARINES... CONTACT LENSES ON SUBMARINES by James F. Socks, CDR, MSC, USN NAVAL SUBMARINE MEDICAL RESEARCH LABORATORY REPORT NUMBER 1048 NAVAL MEDICAL RESEARCH...DRSCHLAB Approved for public release; distribution unlimited SUMMARY PAGE PROBLEM To determine the feasibility of wearing contact lenses aboard

  1. Glasses and Contact Lenses

    MedlinePlus

    ... dientes Video: Getting an X-ray Glasses and Contact Lenses KidsHealth > For Kids > Glasses and Contact Lenses Print A A A What's in this ... together the way they should. But eyeglasses or contact lenses, also called corrective lenses, can help most ...

  2. ADS in a Nutshell

    NASA Astrophysics Data System (ADS)

    Demleitner, M.; Eichhorn, G.; Grant, C. S.; Accomazzi, A.; Murray, S. S.; Kurtz, M. J.

    1999-05-01

    The bibliographic databases maintained by the NASA Astrophysics Data System are updated approximately biweekly with records gathered from over 125 sources all over the world. Data are either sent to us electronically, retrieved by our staff via semi-automated procedures, or entered in our databases through supervised OCR procedures. PERL scripts are run on the data to convert them from their incoming format to our standard format so that they can be added to the master database at SAO. Once new data has been added, separate index files are created for authors, objects, title words, and text word, allowing these fields to be searched for individually or in combination with each other. During the indexing procedure, discipline-specific knowledge is taken into account through the use of rule-based procedures performing string normalization, context-sensitive word translation, and synonym and stop word replacement. Once the master text and index files have been updated at SAO, an automated procedure mirrors the changes in the database to the ADS mirror site via a secure network connection. The use of a public domain software tool called rsync allows incremental updating of the database files, with significant savings in the amount of data being transferred. In the past year, the ADS Abstract Service databases have grown by approximately 30%, including 50% growth in Physics, 25% growth in Astronomy and 10% growth in the Instrumentation datasets. The ADS Abstract Service now contains over 1.4 million abstracts (475K in Astronomy, 430K in Physics, 510K in Instrumentation, and 3K in Preprints), 175,000 journal abstracts, and 115,000 full text articles. In addition, we provide links to over 40,000 electronic HTML articles at other sites, 20,000 PDF articles, and 10,000 postscript articles, as well as many links to other external data sources.

  3. Contact micromechanics in granular media with clay

    SciTech Connect

    Ita, Stacey Leigh

    1994-08-01

    Many granular materials, including sedimentary rocks and soils, contain clay particles in the pores, grain contacts, or matrix. The amount and location of the clays and fluids can influence the mechanical and hydraulic properties of the granular material. This research investigated the mechanical effects of clay at grain-to-grain contacts in the presence of different fluids. Laboratory seismic wave propagation tests were conducted at ultrasonic frequencies using spherical glass beads coated with Montmorillonite clay (SWy-1) onto which different fluids were adsorbed. For all bead samples, seismic velocity increased and attenuation decreased as the contact stiffnesses increased with increasing stress demonstrating that grain contacts control seismic transmission in poorly consolidated and unconsolidated granular material. Coating the beads with clay added stiffness and introduced viscosity to the mechanical contact properties that increased the velocity and attenuation of the propagating seismic wave. Clay-fluid interactions were studied by allowing the clay coating to absorb water, ethyl alcohol, and hexadecane. Increasing water amounts initially increased seismic attenuation due to clay swelling at the contacts. Attenuation decreased for higher water amounts where the clay exceeded the plastic limit and was forced from the contact areas into the surrounding open pore space during sample consolidation. This work investigates how clay located at grain contacts affects the micromechanical, particularly seismic, behavior of granular materials. The need for this work is shown by a review of the effects of clays on seismic wave propagation, laboratory measurements of attenuation in granular media, and proposed mechanisms for attenuation in granular media.

  4. Contact lens in keratoconus

    PubMed Central

    Rathi, Varsha M; Mandathara, Preeji S; Dumpati, Srikanth

    2013-01-01

    Contact lenses are required for the visual improvement in patients with keratoconus. Various contact lens options, such as rigid gas permeable (RGP) lenses, soft and soft toric lenses, piggy back contact lenses (PBCL), hybrid lenses and scleral lenses are availble. This article discusses about selection of a lens depending on the type of keratoconus and the fitting philosophies of various contact lenses including the starting trial lens. A Medline search was carried out for articles in the English language with the keywords keratoconus and various contact lenses such as Rose k lens, RGP lens, hybrid lens, scleral lens and PBCL. PMID:23925325

  5. [Immunology of contact allergy].

    PubMed

    Martin, S F

    2011-10-01

    Contact allergy is a skin disease that is caused by the reaction of the immune system to low molecular weight chemicals. A hallmark of contact allergens is their chemical reactivity, which is not exhibited by toxic irritants. Covalent binding of contact allergens to or complex formation with proteins is essential for the activation of the immune system. As a consequence antigenic epitopes are formed, which are recognized by contact allergen-specific T cells. The generation of effector and memory T cells causes the high antigen specificity and the repeated antigen-specific skin reaction of contact allergy. New findings reveal that the less specific reaction of the innate immune system to contact allergens closely resembles the reaction to an infection. Therefore, contact allergy can be viewed as an immunologic misunderstanding since the skin contact with chemical allergens is interpreted as an infection. The growing understanding of the molecular and cellular pathologic mechanisms of contact allergy can aid the development of specific therapies and of in vitro alternatives to animal testing for the identification of contact allergens.

  6. Non-contact measurement of contact wire

    NASA Astrophysics Data System (ADS)

    Yi, Yaxing; Ye, Xuemei; Li, Zhongke; Yue, Kaiduan

    2008-12-01

    The overhead contact system is the power supply unit of the electric locomotive. This article is to introduce our newly developed method to measure the height and pull out value of the contact wire. A carema dolly which can move on railway is applied to bear the weight of the measure equipment; two linear CCD cameras are installed on the dolly symmetrically about the midline of two rails. While the dolly move along the railway, two CCD cameras grasp the image synchronously, and a computer real-time process the images, the height and pull out value can be calculate out from the images.

  7. 75 FR 27972 - Airworthiness Directives; Pratt & Whitney JT8D-9, -9A, -11, -15, -17, and -17R Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-19

    .... This proposed AD would require overhauling fan blade leading edges at the first shop visit after 4,000 cycles-in-service (CIS) since the last total fan blade overhaul was performed. This proposed AD results from reports of failed fan blades. We are proposing this AD to prevent high-cycle fatigue cracking...

  8. [Periorbital contact eczema].

    PubMed

    Worm, M; Sterry, W

    2005-11-01

    Periorbital contact eczema is most commonly the result of an allergic contact dermatitis whereas other eczematous skin diseases like atopic eczema or seborrheic eczema occur less frequently. Also, other diseases like autoimmune disorders or rosacea need to be considered. Allergic contact dermatitis is a T-cell-mediated immunological response towards ubiquitous contact allergens. Activated T-cells migrate through the vessels into the skin and produce several inflammatory mediators. Epicutaneous patch testing is an important tool for the diagnosis of contact allergy whereby the allergens are analysed in terms of their ability to induce eczematous skin reaction. Until now the short-term use of corticosteroids are is employed for the treatment of allergic contact eczema. Modern substances with an optimal therapeutic index should rather be used.

  9. Contact angle hysteresis explained.

    PubMed

    Gao, Lichao; McCarthy, Thomas J

    2006-07-04

    A view of contact angle hysteresis from the perspectives of the three-phase contact line and of the kinetics of contact line motion is given. Arguments are made that advancing and receding are discrete events that have different activation energies. That hysteresis can be quantified as an activation energy by the changes in interfacial area is argued. That this is an appropriate way of viewing hysteresis is demonstrated with examples.

  10. Soft contact lenses

    PubMed Central

    Sutherland, R. L.; VanLeeuwen, Wm. N.

    1972-01-01

    A series of 55 patients were fitted with a new type of hydrophilic soft contact lens. These were found more comfortable than hard contact lenses and they had a protective and pain-relieving action in cases of chronic corneal disease. Vision was not as good as with hard contact lenses and a greater potential danger of infection was found. They are preferred by many patients despite the noticeable thick edge and the difficulty of obtaining an identical replacement. PMID:5042887

  11. Optical contact micrometer

    DOEpatents

    Jacobson, Steven D.

    2014-08-19

    Certain examples provide optical contact micrometers and methods of use. An example optical contact micrometer includes a pair of opposable lenses to receive an object and immobilize the object in a position. The example optical contact micrometer includes a pair of opposable mirrors positioned with respect to the pair of lenses to facilitate viewing of the object through the lenses. The example optical contact micrometer includes a microscope to facilitate viewing of the object through the lenses via the mirrors; and an interferometer to obtain one or more measurements of the object.

  12. Colors and contact dermatitis.

    PubMed

    Bonamonte, Domenico; Foti, Caterina; Romita, Paolo; Vestita, Michelangelo; Angelini, Gianni

    2014-01-01

    The diagnosis of skin diseases relies on several clinical signs, among which color is of paramount importance. In this review, we consider certain clinical presentations of both eczematous and noneczematous contact dermatitis in which color plays a peculiar role orientating toward the right diagnosis. The conditions that will be discussed include specific clinical-morphologic subtypes of eczematous contact dermatitis, primary melanocytic, and nonmelanocytic contact hyperchromia, black dermographism, contact chemical leukoderma, and others. Based on the physical, chemical, and biologic factors underlying a healthy skin color, the various skin shades drawing a disease picture are thoroughly debated, stressing their etiopathogenic origins and histopathologic aspects.

  13. Contact Noise in Sodium Beta Alumina.

    DTIC Science & Technology

    1987-05-01

    AD-Al~i 128 CONTACT NOISE IN SODIUM BETA ALUMINA(U) UTANHUNIV SALT i/i LAKE CITY DEPT OF PHYSICS C K KUD ET AL MAY 87 UN SLR55IF IED FG 1,b2 NL UN...by Chu Kun Kuo* and James J. Brophy Physics Department University of Utah Salt Lake City, Utah 84112 ABSTRACT/ Contact noise in sodium 0alumina cells...ZIPCo*I) UNIVERSITY OF UTAH UNIVERISTY OF NEW MEXICO SALT LAKE CITY UT 84112 Bandelier Hall West Alhkq..u u. m (1 71-11 so NAME of FUNDING /SPONSORING Sb

  14. Factor XII Contact Activation.

    PubMed

    Naudin, Clément; Burillo, Elena; Blankenberg, Stefan; Butler, Lynn; Renné, Thomas

    2017-03-27

    Contact activation is the surface-induced conversion of factor XII (FXII) zymogen to the serine protease FXIIa. Blood-circulating FXII binds to negatively charged surfaces and this contact to surfaces triggers a conformational change in the zymogen inducing autoactivation. Several surfaces that have the capacity for initiating FXII contact activation have been identified, including misfolded protein aggregates, collagen, nucleic acids, and platelet and microbial polyphosphate. Activated FXII initiates the proinflammatory kallikrein-kinin system and the intrinsic coagulation pathway, leading to formation of bradykinin and thrombin, respectively. FXII contact activation is well characterized in vitro and provides the mechanistic basis for the diagnostic clotting assay, activated partial thromboplastin time. However, only in the past decade has the critical role of FXII contact activation in pathological thrombosis been appreciated. While defective FXII contact activation provides thromboprotection, excess activation underlies the swelling disorder hereditary angioedema type III. This review provides an overview of the molecular basis of FXII contact activation and FXII contact activation-associated disease states.

  15. Noneczematous Contact Dermatitis

    PubMed Central

    Foti, Caterina; Vestita, Michelangelo; Angelini, Gianni

    2013-01-01

    Irritant or allergic contact dermatitis usually presents as an eczematous process, clinically characterized by erythematoedematovesicous lesions with intense itching in the acute phase. Such manifestations become erythematous-scaly as the condition progresses to the subacute phase and papular-hyperkeratotic in the chronic phase. Not infrequently, however, contact dermatitis presents with noneczematous features. The reasons underlying this clinical polymorphism lie in the different noxae and contact modalities, as well as in the individual susceptibility and the various targeted cutaneous structures. The most represented forms of non-eczematous contact dermatitis include the erythema multiforme-like, the purpuric, the lichenoid, and the pigmented kinds. These clinical entities must obviously be discerned from the corresponding “pure” dermatitis, which are not associated with contact with exogenous agents. PMID:24109520

  16. Historical Literature in the ADS

    NASA Astrophysics Data System (ADS)

    Eichhorn, G.; Kurtz, M. J.; Accomazzi, A.; Grant, C. S.

    1997-12-01

    The Astrophysics Data System at http://adswww.harvard.edu is in the process of scanning the historical astronomical literature and making it available through the World Wide Web. We have scanned several volumes from the early 1800's of the "Astronomische Nachrichten", and the "Monthly Notices of the Royal Astronomical Society", the two oldest astronomical journals. We also have several of the early volumes of the "Astrophysical Journal" and the "Astronomical Journal" available. For all the journals that we cover, we have scanned volume 1. These early volumes can be accessed on a page-by-page basis. We plan to continue to scan this historical literature and complete these journals within the next year. We are also collaborating with a preservation project at Harvard University. This project will microfilm selected parts of astronomical Observatory reports. We plan to scan these microfilms to produce electronic images of these reports and put them on-line in the ADS. We hope to eventually cover most of the astronomical literature. In order to organize the scanned pages into articles, we need tables of contents (ToC). The early issues of the journals did not have printed ToC pages, so this needs to be done by hand. We do not have the financial resources to build these ToCs. We are looking for collaborators who would be willing to work with us in building these ToCs for the older journals and observatory reports. If you are interested in such a project, please contact the first author at gei@cfa.harvard.edu.

  17. Supersymmetry of AdS and flat IIB backgrounds

    NASA Astrophysics Data System (ADS)

    Beck, S.; Gutowski, J.; Papadopoulos, G.

    2015-02-01

    We present a systematic description of all warped AdS n × w M 10- n and IIB backgrounds and identify the a priori number of supersymmetries N preserved by these solutions. In particular, we find that the AdS n backgrounds preserve for n ≤ 4 and for 4 < n ≤ 6 supersymmetries and for suitably restricted. In addition under some assumptions required for the applicability of the maximum principle, we demonstrate that the Killing spinors of AdS n backgrounds can be identified with the zero modes of Dirac-like operators on M 10- n establishing a new class of Lichnerowicz type theorems. Furthermore, we adapt some of these results to backgrounds with fluxes by taking the AdS radius to infinity. We find that these backgrounds preserve for 2 < n ≤ 4 and for 4 < n ≤ 7 supersymmetries. We also demonstrate that the Killing spinors of AdS n × w M 10- n do not factorize into Killing spinors on AdS n and Killing spinors on M 10- n .

  18. [Value-Added--Adding Economic Value in the Food Industry].

    ERIC Educational Resources Information Center

    Welch, Mary A., Ed.

    1989-01-01

    This booklet focuses on the economic concept of "value added" to goods and services. A student activity worksheet illustrates how the steps involved in processing food are examples of the concept of value added. The booklet further links food processing to the idea of value added to the Gross National Product (GNP). Discussion questions,…

  19. Pratt & Whitney thermal barrier coatings

    SciTech Connect

    Bornstein, N.; Marcin, J.

    1995-10-01

    The objective of the Advanced Turbine Systems (ATS) Program is to develop ultra-high efficient, environmentally superior, and cost competitive gas turbine systems. The operating profiles of these industrial gas turbines are long, less cyclic with fewer transients-compared with those for aircraft gas turbine engines. Therefore, creep rather than thermal fatigue, becomes primary life-limiting for hot section components. Thermal barrier coatings (TBCs) will be used to achieve the objectives of the program. TBCs allow surface temperatures to increase without compromising the structural properties of the alloy. TBCs typically consist of a ceramic insulating layer, deposited onto the substrate with an intervening metallic layer, which imparts oxidation protection to the substrate and provides a surface to which the ceramic layer can adhere.

  20. Allergic contact dermatitis.

    PubMed

    Becker, Detlef

    2013-07-01

    Allergic contact dermatitis is a frequent inflammatory skin disease. The suspected diagnosis is based on clinical symptoms, a plausible contact to allergens and a suitable history of dermatitis. Differential diagnoses should be considered only after careful exclusion of any causal contact sensitization. Hence, careful diagnosis by patch testing is of great importance. Modifications of the standardized test procedure are the strip patch test and the repeated open application test. The interpretation of the SLS (sodium lauryl sulfate) patch test as well as testing with the patients' own products and working materials are potential sources of error. Accurate patch test reading is affected in particular by the experience and individual factors of the examiner. Therefore, a high degree of standardization and continuous quality control is necessary and may be supported by use of an online patch test reading course made available by the German Contact Dermatitis Research Group. A critical relevance assessment of allergic patch test reactions helps to avoid relapses and the consideration of differential diagnoses. Any allergic test reaction should be documented in an allergy ID card including the INCI name, if appropriate. The diagnostics of allergic contact dermatitis is endangered by a seriously reduced financing of patch testing by the German statutory health insurances. Restrictive regulations by the German Drug Law block the approval of new contact allergens for routine patch testing. Beside the consistent avoidance of allergen contact, temporary use of systemic and topical corticosteroids is the therapy of first choice.

  1. Telescopic vision contact lens

    NASA Astrophysics Data System (ADS)

    Tremblay, Eric J.; Beer, R. Dirk; Arianpour, Ashkan; Ford, Joseph E.

    2011-03-01

    We present the concept, optical design, and first proof of principle experimental results for a telescopic contact lens intended to become a visual aid for age-related macular degeneration (AMD), providing magnification to the user without surgery or external head-mounted optics. Our contact lens optical system can provide a combination of telescopic and non-magnified vision through two independent optical paths through the contact lens. The magnified optical path incorporates a telescopic arrangement of positive and negative annular concentric reflectors to achieve 2.8x - 3x magnification on the eye, while light passing through a central clear aperture provides unmagnified vision.

  2. Optical contacting of quartz

    NASA Technical Reports Server (NTRS)

    Payne, L. L.

    1982-01-01

    The strength of the bond between optically contacted quartz surfaces was investigated. The Gravity Probe-B (GP-B) experiment to test the theories of general relativity requires extremely precise measurements. The quartz components of the instruments to make these measurements must be held together in a very stable unit. Optical contacting is suggested as a possible method of joining these components. The fundamental forces involved in optical contacting are reviewed and relates calculations of these forces to the results obtained in experiments.

  3. AdS3 Solutions of IIB Supergravity

    SciTech Connect

    Kim, Nakwoo

    2005-12-02

    We consider pure D3-brane configurations of IIB string theory which lead to supergravity solutions containing an AdS3 factor. They can provide new examples of AdS3/CFT2 examples on D3-branes whose worldvolume is partially compactified. When the internal 7 dimensional space is non-compact, they are related to fluctuations of higher dimensional AdS/CFT duality examples, thus dual to the BPS operators of D = 4 superconformal field theories. We find that supersymmetry requires the 7 dimensional space is warped Hopf-fibration of (real) 6 dimensional Kahler manifolds.

  4. Action growth for AdS black holes

    NASA Astrophysics Data System (ADS)

    Cai, Rong-Gen; Ruan, Shan-Ming; Wang, Shao-Jiang; Yang, Run-Qiu; Peng, Rong-Hui

    2016-09-01

    Recently a Complexity-Action (CA) duality conjecture has been proposed, which relates the quantum complexity of a holographic boundary state to the action of a Wheeler-DeWitt (WDW) patch in the anti-de Sitter (AdS) bulk. In this paper we further investigate the duality conjecture for stationary AdS black holes and derive some exact results for the growth rate of action within the Wheeler-DeWitt (WDW) patch at late time approximation, which is supposed to be dual to the growth rate of quantum complexity of holographic state. Based on the results from the general D-dimensional Reissner-Nordström (RN)-AdS black hole, rotating/charged Bañados-Teitelboim-Zanelli (BTZ) black hole, Kerr-AdS black hole and charged Gauss-Bonnet-AdS black hole, we present a universal formula for the action growth expressed in terms of some thermodynamical quantities associated with the outer and inner horizons of the AdS black holes. And we leave the conjecture unchanged that the stationary AdS black hole in Einstein gravity is the fastest computer in nature.

  5. Value Added in English Schools

    ERIC Educational Resources Information Center

    Ray, Andrew; McCormack, Tanya; Evans, Helen

    2009-01-01

    Value-added indicators are now a central part of school accountability in England, and value-added information is routinely used in school improvement at both the national and the local levels. This article describes the value-added models that are being used in the academic year 2007-8 by schools, parents, school inspectors, and other…

  6. Constructing the AdS dual of a Fermi liquid: AdS black holes with Dirac hair

    NASA Astrophysics Data System (ADS)

    Čubrović, Mihailo; Zaanen, Jan; Schalm, Koenraad

    2011-10-01

    We provide evidence that the holographic dual to a strongly coupled charged Fermi liquid has a non-zero fermion density in the bulk. We show that the pole-strength of the stable quasiparticle characterizing the Fermi surface is encoded in the AdS probability density of a single normalizable fermion wavefunction in AdS. Recalling Migdal's theorem which relates the pole strength to the Fermi-Dirac characteristic discontinuity in the number density at ω F , we conclude that the AdS dual of a Fermi liquid is described by occupied on-shell fermionic modes in AdS. Encoding the occupied levels in the total spatially averaged probability density of the fermion field directly, we show that an AdS Reissner-Nordström black holein a theory with charged fermions has a critical temperature, at which the system undergoes a first-order transition to a black hole with a non-vanishing profile for the bulk fermion field. Thermodynamics and spectral analysis support that the solution with non-zero AdS fermion-profile is the preferred ground state at low temperatures.

  7. Occupational Contact Dermatitis

    PubMed Central

    2008-01-01

    Occupational contact dermatitis accounts for 90% of all cases of work-related cutaneous disorders. It can be divided into irritant contact dermatitis, which occurs in 80% of cases, and allergic contact dermatitis. In most cases, both types will present as eczematous lesions on exposed parts of the body, notably the hands. Accurate diagnosis relies on meticulous history taking, thorough physical examination, careful reading of Material Safety Data Sheets to distinguish between irritants and allergens, and comprehensive patch testing to confirm or rule out allergic sensitization. This article reviews the pathogenesis and clinical manifestations of occupational contact dermatitis and provides diagnostic guidelines and a rational approach to management of these often frustrating cases. PMID:20525126

  8. SAM Technical Contacts

    EPA Pesticide Factsheets

    These technical contacts are available to help with questions regarding method deviations, modifications, sample problems or interferences, quality control requirements, the use of alternative methods, or the need to address analytes or sample types.

  9. Fragrance allergic contact dermatitis.

    PubMed

    Cheng, Judy; Zug, Kathryn A

    2014-01-01

    Fragrances are a common cause of allergic contact dermatitis in Europe and in North America. They can affect individuals at any age and elicit a spectrum of reactions from contact urticaria to systemic contact dermatitis. Growing recognition of the widespread use of fragrances in modern society has fueled attempts to prevent sensitization through improved allergen identification, labeling, and consumer education. This review provides an overview and update on fragrance allergy. Part 1 discusses the epidemiology and evaluation of suspected fragrance allergy. Part 2 reviews screening methods, emerging fragrance allergens, and management of patients with fragrance contact allergy. This review concludes by examining recent legislation on fragrances and suggesting potential additions to screening series to help prevent and detect fragrance allergy.

  10. Contact air abrasion.

    PubMed

    Porth, R

    1999-05-01

    The advantages of contact air abrasion techniques are readily apparent. The first, of course, is the greatly increased ease of use. Working with contact also tends to speed the learning curve by giving the process a more natural dental feel. In addition, as one becomes familiar with working with a dust stream, the potential for misdirecting the air flow is decreased. The future use of air abrasion for deep decay removal will make this the treatment of choice for the next millennium.

  11. Contact dermatitis complicating pinnaplasty.

    PubMed

    Singh-Ranger, G; Britto, J A; Sommerlad, B C

    2001-04-01

    Proflavine allergy is uncommon, occurring in approximately 6% of patients attending contact dermatitis clinics. Proflavine wool is used by many surgeons in the UK as a dressing that can be moulded to conform to the contours of a corrected prominent ear. It may have bacteriostatic properties. We present a case where contact dermatitis in response to proflavine developed after pinnaplasty. This caused diagnostic confusion, a lengthened hospital stay and an unsightly hypertrophic scar.

  12. The impact of contact

    NASA Astrophysics Data System (ADS)

    Finney, B.

    1986-10-01

    Scenarios of the impact on human society of radio contact with an extraterrestrial civilization are presented. Some believe that contact with advanced extraterrestrials would quickly devastate the human spirit, while others believe that these super-intelligent beings would show the inhabitants of the earth how to live in peace. It is proposed that the possible existence of extraterrestrial civilizations and the development of means of studying and communicating with them need to be considered.

  13. ELECTRIC CONTACT MEANS

    DOEpatents

    Grear, J.W. Jr.

    1959-03-10

    A switch adapted to maintain electrical connections under conditions of vibration or acceleration is described. According to the invention, thc switch includes a rotatable arm carrying a conductive bar arranged to close against two contacts spaced in the same plane. The firm and continuous engagement of the conductive bar with the contacts is acheived by utilizeing a spring located betwenn the vbar and athe a rem frzme and slidable mounting the bar in channel between two arms suspendef from the arm frame.

  14. Lettuce contact allergy.

    PubMed

    Paulsen, Evy; Andersen, Klaus E

    2016-02-01

    Lettuce (Lactuca sativa L.) and its varieties are important vegetable crops worldwide. They are also well-known, rarely reported, causes of contact allergy. As lettuce allergens and extracts are not commercially available, the allergy may be underdiagnosed. The aims of this article are to present new data on lettuce contact allergy and review the literature. Lettuce is weakly allergenic, and occupational cases are mainly reported. Using aimed patch testing in Compositae-allergic patients, two recent Danish studies showed prevalence rates of positive lettuce reactions of 11% and 22%. The majority of cases are non-occupational, and may partly be caused by cross-reactivity. The sesquiterpene lactone mix seems to be a poor screening agent for lettuce contact allergy, as the prevalence of positive reactions is significantly higher in non-occupationally sensitized patients. Because of the easy degradability of lettuce allergens, it is recommended to patch test with freshly cut lettuce stem and supplement this with Compositae mix. As contact urticaria and protein contact dermatitis may present as dermatitis, it is important to perform prick-to-prick tests, and possibly scratch patch tests as well. Any person who is occupationally exposed to lettuce for longer periods, especially atopics, amateur gardeners, and persons keeping lettuce-eating pets, is potentially at risk of developing lettuce contact allergy.

  15. AdS-Carroll branes

    NASA Astrophysics Data System (ADS)

    Clark, T. E.; ter Veldhuis, T.

    2016-11-01

    Coset methods are used to determine the action of a co-dimension one brane (domain wall) embedded in (d + 1)-dimensional AdS space in the Carroll limit in which the speed of light goes to zero. The action is invariant under the non-linearly realized symmetries of the AdS-Carroll spacetime. The Nambu-Goldstone field exhibits a static spatial distribution for the brane with a time varying momentum density related to the brane's spatial shape as well as the AdS-C geometry. The AdS-C vector field dual theory is obtained.

  16. ADS Based on Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Pan, Weimin; Dai, Jianping

    An accelerator-driven system (ADS), which combines a particle accelerator with a subcritical core, is commonly regarded as a promising device for the transmutation of nuclear waste, as well as a potential scheme for thorium-based energy production. So far the predominant choice of the accelerator for ADS is a superconducting linear accelerator (linac). This article gives a brief overview of ADS based on linacs, including the motivation, principle, challenges and research activities around the world. The status and future plan of the Chinease ADS (C-ADS) project will be highlighted and discussed in depth as an example.

  17. AdS spacetimes from wrapped D3-branes

    NASA Astrophysics Data System (ADS)

    Gauntlett, Jerome P.; MacConamhna, Oisín A. P.

    2007-12-01

    We derive a geometrical characterization of a large class of AdS3 and AdS2 supersymmetric spacetimes in type IIB supergravity with non-vanishing five-form flux using G-structures. These are obtained as special cases of a class of supersymmetric spacetimes with an {{\\bb R}}^{1,1} or {{\\bb R}} (time) factor that are associated with D3 branes wrapping calibrated two or three cycles, respectively, in manifolds with SU(2), SU(3), SU(4) and G2 holonomy. We show how two explicit AdS solutions, previously constructed in gauged supergravity, satisfy our more general G-structure conditions. For each explicit solution, we also derive a special holonomy metric which, although singular, has an appropriate calibrated cycle. After analytic continuation, some of the classes of AdS spacetimes give rise to known classes of BPS bubble solutions with {{\\bb R}}\\times {\\it SO}(4)\\times {\\it SO}(4), {{\\bb R}}\\times {\\it SO}(4)\\times U(1) and {{\\bb R}}\\times {\\it SO}(4) symmetry. These have 1/2, 1/4 and 1/8 supersymmetry, respectively. We present a new class of 1/8 BPS geometries with {{\\bb R}}\\times {\\it SU}(2) symmetry, obtained by analytic continuation of the class of AdS spacetimes associated with D3-brane wrapped on associative three cycles.

  18. Revisiting the thermodynamic relations in AdS /CMT models

    NASA Astrophysics Data System (ADS)

    Hyun, Seungjoon; Park, Sang-A.; Yi, Sang-Heon

    2017-03-01

    Motivated by the recent unified approach to the Smarr-like relation of anti-de Sitter (AdS) planar black holes in conjunction with the quasilocal formalism on conserved charges, we revisit the quantum statistical and thermodynamic relations of hairy AdS planar black holes. By extending the previous results, we identify the hairy contribution in the bulk and show that the holographic computation can be improved so that it is consistent with the bulk computation. We argue that the first law can be retained in its universal form and that the relation between the on-shell renormalized Euclidean action and its free energy interpretation in gravity may also be undeformed even with the hairy contribution in hairy AdS black holes.

  19. Entanglement entropy for free scalar fields in AdS

    NASA Astrophysics Data System (ADS)

    Sugishita, Sotaro

    2016-09-01

    We compute entanglement entropy for free massive scalar fields in anti-de Sitter (AdS) space. The entangling surface is a minimal surface whose boundary is a sphere at the boundary of AdS. The entropy can be evaluated from the thermal free energy of the fields on a topological black hole by using the replica method. In odd-dimensional AdS, exact expressions of the Rényi entropy S n are obtained for arbitrary n. We also evaluate 1-loop corrections coming from the scalar fields to holographic entanglement entropy. Applying the results, we compute the leading difference of entanglement entropy between two holographic CFTs related by a renormalization group flow triggered by a double trace deformation. The difference is proportional to the shift of a central charge under the flow.

  20. Solutions of free higher spins in AdS

    NASA Astrophysics Data System (ADS)

    Lü, H.; Shao, Kai-Nan

    2011-11-01

    We consider free massive and massless higher integer spins in AdS backgrounds in general D dimensions. We obtain the solutions corresponding to the highest-weight state of the spin-ℓ representations of the SO (2 , D - 1) isometry groups. The solution for the spin-ℓ field is expressed recursively in terms of that for the spin- (ℓ - 1). Thus starting from the explicit spin-0, all the higher-spin solutions can be obtained. These solutions allow us to derive the generalized Breitenlohner-Freedman bound, and analyze the asymptotic falloffs. In particular, solutions with negative mass square in general have falloffs slower than those of the Schwarzschild AdS black holes in the AdS boundaries.

  1. The contact caveat: negative contact predicts increased prejudice more than positive contact predicts reduced prejudice.

    PubMed

    Barlow, Fiona Kate; Paolini, Stefania; Pedersen, Anne; Hornsey, Matthew J; Radke, Helena R M; Harwood, Jake; Rubin, Mark; Sibley, Chris G

    2012-12-01

    Contact researchers have largely overlooked the potential for negative intergroup contact to increase prejudice. In Study 1, we tested the interaction between contact quantity and valence on prejudice toward Black Australians (n = 1,476), Muslim Australians (n = 173), and asylum seekers (n = 293). In all cases, the association between contact quantity and prejudice was moderated by its valence, with negative contact emerging as a stronger and more consistent predictor than positive contact. In Study 2, White Americans (n = 441) indicated how much positive and negative contact they had with Black Americans on separate measures. Although both quantity of positive and negative contact predicted racism and avoidance, negative contact was the stronger predictor. Furthermore, negative (but not positive) contact independently predicted suspicion about Barack Obama's birthplace. These results extend the contact hypothesis by issuing an important caveat: Negative contact may be more strongly associated with increased racism and discrimination than positive contact is with its reduction.

  2. Improvements in contact resistivity and thermal stability of Au-contacted InP solar cells

    NASA Technical Reports Server (NTRS)

    Fatemi, Navid S.; Weizer, Victor G.

    1991-01-01

    Specific contact resistivities for as-fabricated Au contacts on n-p InP solar cells are typically in the 10(exp -3) ohm/sq cm range, but contact resistivities in the 10(exp -6) ohm/sq cm range can be obtained if the cells are heat treated at 400 C for a few minutes. This heat treatment, however, results in a dramatic drop in the open circuit voltage of the cell due to excessive dissolution of the emitter into the metallization. It was found that low values of contact resistivity can be secured without the accompanying drop in the open circuit voltage by adding Ga and In in the Au metallization. It is shown that Au contacts containing as little as 1 percent atomic Ga can suppress the reaction that takes place at the metal-InP interface during heat treatment, while exhibiting contact resistivity values in the low 10(exp -5) ohm/sq cm. Detailed explanations for the observed superior thermal stability of these contacts are presented.

  3. Focusing on Contact Lens Safety

    MedlinePlus

    ... Consumers Home For Consumers Consumer Updates Focusing on Contact Lens Safety Share Tweet Linkedin Pin it More ... substantial consumer injury. Back to top Types of Contact Lenses General categories Soft contact lenses. These are ...

  4. Diffusion and chaos from near AdS2 horizons

    NASA Astrophysics Data System (ADS)

    Blake, Mike; Donos, Aristomenis

    2017-02-01

    We calculate the thermal diffusivity D = κ/c ρ and butterfly velocity v B in holographic models that flow to AdS2 × R d fixed points in the infra-red. We show that both these quantities are governed by the same irrelevant deformation of AdS2 and hence establish a simple relationship between them. When this deformation corresponds to a universal dilaton mode of dimension Δ = 2 then this relationship is always given by D = v B 2 /(2 πT).

  5. Reply to “Comment on ‘Near-surface location, geometry, and velocities of the Santa Monica fault zone, Los Angeles, California’ by R. D. Catchings, G. Gandhok, M. R. Goldman, D. Okaya, M. J. Rymer, and G. W. Bawden” by T. L. Pratt and J. F. Dolan

    USGS Publications Warehouse

    Catchings, Rufus D.; Rymer, Michael J.; Goldman, Mark R.; Bawden, Gerald W.

    2010-01-01

    In a comment on our 2008 paper (Catchings, Gandhok, et al., 2008) on the Santa Monica fault in Los Angeles, California, Pratt and Dolan (2010) (herein referred to as P&D) cite numerous objections to our work, inferring that our study is flawed. However, as shown in our reply, their objections contradict their own published works, published works of others, and proven seismic methodologies. Rather than responding to each repeated invalid objection, we address their objections by topic in the subsequent sections.In Catchings, Gandhok, et al. (2008), we presented high-resolution seismic-reflection images that showed two near-surface faults in the upper 50 m beneath the grounds of the Wadsworth Veterans Administration Hospital (WVAH). Although P&D suggest we effectively duplicated their seismic acquisition, our survey was not a duplication of their efforts. Rather, we conducted a seismic-imaging survey over a similar profile as Pratt et al. (1998) but used a different data acquisition system and different data processing methods to evaluate methods of seismically imaging blind faults in the wake of the 17 January 1994 M 6.7 Northridge earthquake. We used an acquisition method that provides both tomographic seismic velocities and reflection images. Our combined-data approach allowed for shallower imaging (∼2.5 m minimum) than the ∼20-m minimum of Pratt et al. (1998), clearer images of the fault zone, and more accurate depth determinations (rather than time images). In processing the reflection images, we used prestack depth migration, which is generally accepted as the only proper imaging method for imaging subsurface structures with strong lateral velocity variations (Versteeg, 1993), a condition shown to exist at the WVAH site. We correlated our reflection images with refraction tomography images, borehole lithology, and velocity data, Interferometric Synthetic Aperture Radar images, and changes in groundwater depths. Except for some minor differences, our

  6. Allergic contact dermatitis.

    PubMed

    Alikhan, Ali; Maibach, Howard I

    2014-01-01

    Allergic contact dermatitis is one of the most important dermatologic disorders worldwide - it can cause significant morbidity and decreased quality of life, as well as having major economic implications and loss of vocational productivity. Patch testing is the most important discovery in allergic contact dermatitis and the best diagnostic modality to date; the thin-layer rapid- use epicutaneous (TRUE) test is a more recent patch test development which has improved the convenience and feasibility of the test. The future of allergic contact dermatitis is bright as we continue to learn more about the science of the disorder, as well as ways to improve diagnosis and patient care. Furthermore, it is important to remember, in this global age, that cooperation between health care providers worldwide is essential.

  7. [Contact glass tonometer].

    PubMed

    Kanngiesser, H; Robert, Y; Dekker, P

    1996-10-01

    This paper present a tonometer incorporated in a contact lens, which allows simultaneous measurement of intraocular pressure and performance ophthalmoscopy. The tonometer can record the pulse curve continuously, which can give us an indication of any circulatory problem. The device is therefore expected to yield additional information useful for the diagnosis of early glaucoma. Te device has three force sensors built in, which allow continuous measurement of the force exerted on the eye surface by the contact lens. The force of the contact lens on the eye can be altered and makes the adjustment of different eye pressures possible. These induced changes of the eye pressure and their influence on the fundus can be checked. We have taken some measurements on enucleated human eyes to compare our device with a Statham tansducer in the vitreous. We found a good correlation. We are currently taking measurements in volunteers. The clinical relevance of these observations and measurements will be examined in a future study.

  8. Shoe allergic contact dermatitis.

    PubMed

    Matthys, Erin; Zahir, Amir; Ehrlich, Alison

    2014-01-01

    Foot dermatitis is a widespread condition, affecting men and women of all ages. Because of the location, this condition may present as a debilitating problem to those who have it. Allergic contact dermatitis involving the feet is frequently due to shoes or socks. The allergens that cause shoe dermatitis can be found in any constituent of footwear, including rubber, adhesives, leather, dyes, metals, and medicaments. The goal of treatment is to identify and minimize contact with the offending allergen(s). The lack of product information released from shoe manufacturers and the continually changing trends in footwear present a challenge in treating this condition. The aim of this study is to review the current literature on allergic contact shoe dermatitis; clinical presentation, allergens, patch testing, and management will be discussed. PubMed and MEDLINE databases were used for the search, with a focus on literature updates from the last 15 years.

  9. Acrylate Systemic Contact Dermatitis.

    PubMed

    Sauder, Maxwell B; Pratt, Melanie D

    2015-01-01

    Acrylates, the 2012 American Contact Dermatitis Society allergen of the year, are found in a range of products including the absorbent materials within feminine hygiene pads. When fully polymerized, acrylates are nonimmunogenic; however, if not completely cured, the monomers can be potent allergens.A 28-year-old woman is presented, who had her teeth varnished with Isodan (Septodont, Saint-Maur-des-Fossés, France) containing HEMA (2-hydroxyethyl methacrylate) with no initial reaction. Approximately 1 month later, the patient developed a genital dermatitis secondary to her feminine hygiene pads. The initial reaction resolved, but 5 months later, the patient developed a systemic contact dermatitis after receiving a second varnishing.The patient was dramatically patch test positive to many acrylates. This case demonstrates a reaction to likely unpolymerized acrylates within a feminine hygiene pad, as well as broad cross-reactivity or cosensitivity to acrylates, and possibly a systemic contact dermatitis with systemic re-exposure to unpolymerized acrylates.

  10. Mystery cloud of AD 536

    NASA Technical Reports Server (NTRS)

    Stothers, R. B.

    1984-01-01

    The possible cause of the densest and most persistent dry fog on record, which was observed in Europe and the Middle East during AD 536 and 537, is discussed. The fog's long duration toward the south and the high sulfuric acid signal detected in Greenland in ice cores dated around AD 540 support the theory that the fog was due to the explosion of the Rabaul volcano, the occurrence of which has been dated at about AD 540 by the radiocarbon method.

  11. Spa contact dermatitis.

    PubMed

    Yankura, Jessica A; Marks, James G; Anderson, Bryan E; Adams, David R

    2008-01-01

    Potassium monopersulfate (MPS) is widely used in spa and pool "shock" treatments, yet contact dermatitis associated with MPS has been rarely reported. A patient presented with a generalized scattered dermatitis from the neck down that worsened after spa use. Patch testing elicited a ++ reaction to ammonium persulfate. Contact with ammonium persulfate was ruled out; however, MPS, which can cross-react with ammonium persulfate, was found to be the active ingredient in the patient's spa shock treatments. The dermatitis cleared after the patient switched to a hydrogen peroxide-based shock treatment.

  12. Allergic Contact Dermatitis.

    PubMed

    Kostner, Lisa; Anzengruber, Florian; Guillod, Caroline; Recher, Mike; Schmid-Grendelmeier, Peter; Navarini, Alexander A

    2017-02-01

    Allergic contact dermatitis (ACD) is a common skin disease caused by a T cell-mediated immune reaction to usually innocuous allergens. ACD can have grave medical and socioeconomic consequences. ACD and irritant contact dermatitis often occur together. A detailed history and clinical examination are crucial and guide patch testing, which is the gold standard to diagnose ACD. T-cell clones persisting in the skin may explain the tendency of ACD to relapse even after years of allergen avoidance. Traditional treatments for ACD are topical steroids, calcineurin inhibitors, phototherapy, retinoids (including the recent alitretinoin), and immunosuppressants. Targeted therapies are lacking.

  13. Coset construction of AdS particle dynamics

    NASA Astrophysics Data System (ADS)

    Heinze, Martin; Jorjadze, George; Megrelidze, Luka

    2017-01-01

    We analyze the dynamics of the AdSN+1 particle realized on the coset SO(2, N)/SO (1,N). Hamiltonian reduction provides the physical phase space in terms of the coadjoint orbit obtained by boosting a timelike element of 𝔰𝔬(2, N). We show equivalence of this approach to geometric quantization and to the SO(N) covariant oscillator description, for which the boost generators entail a complicated operator ordering. As an alternative scheme, we introduce dual oscillator variables and derive their algebra at the classical and the quantum levels. This simplifies the calculations of the commutators for the boost generators and leads to unitary irreducible representations of 𝔰𝔬(2, N) for all admissible values of the mass parameter. We furthermore discuss an SO(N) covariant supersymmetric extension of the oscillator quantization, with its realization for superparticles in AdS2 and AdS3 given by recent works.

  14. Entanglement temperature and perturbed AdS3 geometry

    NASA Astrophysics Data System (ADS)

    Levine, G. C.; Caravan, B.

    2016-06-01

    Generalizing the first law of thermodynamics, the increase in entropy density δ S (x ) of a conformal field theory (CFT) is proportional to the increase in energy density, δ E (x ) , of a subsystem divided by a spatially dependent entanglement temperature, TE(x ) , a fixed parameter determined by the geometry of the subsystem, crossing over to thermodynamic temperature at high temperatures. In this paper we derive a generalization of the thermodynamic Clausius relation, showing that deformations of the CFT by marginal operators are associated with spatial temperature variations, δ TE(x ) , and spatial energy correlations play the role of specific heat. Using AdS/CFT duality we develop a relationship between a perturbation in the local entanglement temperature of the CFT and the perturbation of the bulk AdS metric. In two dimensions, we demonstrate a method through which direct diagonalizations of the boundary quantum theory may be used to construct geometric perturbations of AdS3 .

  15. AdS5 backgrounds with 24 supersymmetries

    NASA Astrophysics Data System (ADS)

    Beck, S.; Gutowski, J.; Papadopoulos, G.

    2016-06-01

    We prove a non-existence theorem for smooth AdS 5 solutions with connected, compact without boundary internal space that preserve strictly 24 supersymmetries. In particular, we show that D = 11 supergravity does not admit such solutions, and that all such solutions of IIB supergravity are locally isometric to the AdS 5 × S 5 maximally supersymmetric background. Furthermore, we prove that (massive) IIA supergravity also does not admit such solutions, provided that the homogeneity conjecture for massive IIA supergravity is valid. In the context of AdS/CFT these results imply that if gravitational duals for strictly mathcal{N}=3 superconformal theories in 4-dimensions exist, they are either singular or their internal spaces are not compact.

  16. Have Confidence in Contact

    ERIC Educational Resources Information Center

    Crisp, Richard J.; Turner, Rhiannon N.

    2010-01-01

    In an article in the May-June 2009 "American Psychologist," we discussed a new approach to reducing prejudice and encouraging more positive intergroup relations (Crisp & Turner, 2009). We named the approach imagined intergroup contact and defined it as "the mental simulation of a social interaction with a member or members of an outgroup category"…

  17. Compact contacting device

    NASA Technical Reports Server (NTRS)

    Acharya, Arun (Inventor); Gottzmann, Christian F. (Inventor); Lockett, Michael J. (Inventor); Schneider, James S. (Inventor); Victor, Richard A. (Inventor); Zawierucha, Robert (Inventor)

    1994-01-01

    An apparatus comprising a rotatable mass of structured packing for mass or heat transfer between two contacting fluids of different densities wherein the packing mass is made up of corrugated sheets of involute shape relative to the axis of the packing mass and form a logarithmic spiral curved counter to the direction of rotation.

  18. Contact: Releasing the news

    NASA Astrophysics Data System (ADS)

    Pinotti, Roberto

    The problem of mass behavior after man's future contacts with other intelligences in the universe is not only a challenge for social scientists and political leaders all over the world, but also a cultural time bomb as well. In fact, since the impact of CETI (Contact with Extraterrestrial Intelligence) on human civilization, with its different cultures, might cause a serious socio-anthropological shock, a common and predetermined worldwide strategy is necessary in releasing the news after the contact, in order to keep possible manifestations of fear, panic and hysteria under control. An analysis of past studies in this field and of parallel historical situations as analogs suggests a definite "authority crisis" in the public as a direct consequence of an unexpected release of the news, involving a devastating "chain reaction" process (from both the psychological and sociological viewpoints) of anomie and maybe the collapse of today's society. The only way to prevent all this is to prepare the world's public opinion concerning contact before releasing the news, and to develop a long-term strategy through the combined efforts of scientists, political leaders, intelligence agencies and the mass media, in order to create the cultural conditions in which a confrontation with ETI won't affect mankind in a traumatic way. Definite roles and tasks in this multi-level model are suggested.

  19. Disproportionate Minority Contact.

    PubMed

    Fix, Rebecca L; Cyperski, Melissa A; Burkhart, Barry R

    2017-04-01

    The overrepresentation of racial/ethnic minorities within the criminal justice system relative to their population percentage, a phenomenon termed disproportionate minority contact, has been examined within general adult and adolescent offender populations; yet few studies have tested whether this phenomenon extends to juvenile sexual offenders (JSOs). In addition, few studies have examined whether offender race/ethnicity influences registration and notification requirements, which JSOs are subject to in some U.S. states. The present study assessed for disproportionate minority contact among general delinquent offenders and JSOs, meaning it aimed to test whether the criminal justice system treats those accused of sexual and non-sexual offenses differently by racial/ethnic group. Furthermore, racial/ethnic group differences in risk, legal classification, and sexual offending were examined for JSOs. Results indicated disproportionate minority contact was present among juveniles with non-sexual offenses and JSOs in Alabama. In addition, offense category and risk scores differed between African American and European American JSOs. Finally, registration classifications were predicted by offending characteristics, but not race/ethnicity. Implications and future directions regarding disproportionate minority contact among JSOs and social and legal policy affecting JSOs are discussed.

  20. Lubrication Of Nonconformal Contacts

    NASA Technical Reports Server (NTRS)

    Jeng, Yeau-Ren

    1991-01-01

    Report discusses advances in knowledge of lubrication of nonconformal contacts in bearings and other machine elements. Reviews previous developments in theory of lubrication, presents advances in theory of lubrication to determine minimum film thickness, and describes experiments designed to investigate one of regimes of lubrication for ball bearings.

  1. Thermal Contact Conductance

    NASA Technical Reports Server (NTRS)

    Salerno, Louis J.; Kittel, Peter

    1997-01-01

    The performance of cryogenic instruments is often a function of their operating temperature. Thus, designers of cryogenic instruments often are required to predict the operating temperature of each instrument they design. This requires accurate thermal models of cryogenic components which include the properties of the materials and assembly techniques used. When components are bolted or otherwise pressed together, a knowledge of the thermal performance of such joints are also needed. In some cases, the temperature drop across these joints represents a significant fraction of the total temperature difference between the instrument and its cooler. While extensive databases exist on the thermal properties of bulk materials, similar databases for pressed contacts do not. This has often lead to instrument designs that avoid pressed contacts or to the over-design of such joints at unnecessary expense. Although many people have made measurements of contact conductances at cryogenic temperatures, this data is often very narrow in scope and even more often it has not been published in an easily retrievable fashion, if published at all. This paper presents a summary of the limited pressed contact data available in the literature.

  2. Exploring the bulk in AdS /CFT : A covariant approach

    NASA Astrophysics Data System (ADS)

    Engelhardt, Netta

    2017-03-01

    I propose a general, covariant way of defining when one region is "deeper in the bulk" than another. This definition is formulated outside of an event horizon (or in the absence thereof) in generic geometries; it may be applied to both points and surfaces, and it may be used to compare the depth of bulk points or surfaces relative to a particular boundary subregion or relative to the entire boundary. Using the recently proposed "light-cone cut" formalism, the comparative depth between two bulk points can be determined from the singularity structure of Lorentzian correlators in the dual field theory. I prove that, by this definition, causal wedges of progressively larger regions probe monotonically deeper in the bulk. The definition furthermore matches expectations in pure AdS and in static AdS black holes with isotropic spatial slices, where a well-defined holographic coordinate exists. In terms of holographic renormalization group flow, this new definition of bulk depth makes contact with coarse graining over both large distances and long time scales.

  3. The exceptional generalised geometry of supersymmetric AdS flux backgrounds

    NASA Astrophysics Data System (ADS)

    Ashmore, Anthony; Petrini, Michela; Waldram, Daniel

    2016-12-01

    We analyse generic AdS flux backgrounds preserving eight supercharges in D = 4 and D = 5 dimensions using exceptional generalised geometry. We show that they are described by a pair of globally defined, generalised structures, identical to those that appear for flat flux backgrounds but with different integrability conditions. We give a number of explicit examples of such "exceptional Sasaki-Einstein" backgrounds in type IIB supergravity and M-theory. In particular, we give the complete analysis of the generic AdS5 M-theory backgrounds. We also briefly discuss the structure of the moduli space of solutions. In all cases, one structure defines a "generalised Reeb vector" that generates a Killing symmetry of the background corresponding to the R-symmetry of the dual field theory, and in addition encodes the generic contact structures that appear in the D = 4 M-theory and D = 5 type IIB cases. Finally, we investigate the relation between generalised structures and quantities in the dual field theory, showing that the central charge and R-charge of BPS wrapped-brane states are both encoded by the generalised Reeb vector, as well as discussing how volume minimisation (the dual of a- and F-maximisation) is encoded.

  4. Lorentzian AdS geometries, wormholes, and holography

    SciTech Connect

    Arias, Raul E.; Silva, Guillermo A.; Botta Cantcheff, Marcelo

    2011-03-15

    We investigate the structure of two-point functions for the quantum field theory dual to an asymptotically Lorentzian Anti de Sitter (AdS) wormhole. The bulk geometry is a solution of five-dimensional second-order Einstein-Gauss-Bonnet gravity and causally connects two asymptotically AdS spacetimes. We revisit the Gubser-Klebanov-Polyakov-Witten prescription for computing two-point correlation functions for dual quantum field theories operators O in Lorentzian signature and we propose to express the bulk fields in terms of the independent boundary values {phi}{sub 0}{sup {+-}} at each of the two asymptotic AdS regions; along the way we exhibit how the ambiguity of normalizable modes in the bulk, related to initial and final states, show up in the computations. The independent boundary values are interpreted as sources for dual operators O{sup {+-}} and we argue that, apart from the possibility of entanglement, there exists a coupling between the degrees of freedom living at each boundary. The AdS{sub 1+1} geometry is also discussed in view of its similar boundary structure. Based on the analysis, we propose a very simple geometric criterion to distinguish coupling from entanglement effects among two sets of degrees of freedom associated with each of the disconnected parts of the boundary.

  5. Contact-resistance process cliff

    NASA Technical Reports Server (NTRS)

    Pina, C. A.

    1985-01-01

    Several approaches were investigated to obtain a measure of the quality of the contact resistance between metal and a diffused or polysilicon layer. These approaches have included the use of both short and very long contact strings as well as arays of contacts with different sizes to determine the contact resistance process cliff. Results from these approaches are discussed.

  6. Allergic contact dermatitis in children.

    PubMed

    Fontana, E; Belloni Fortina, A

    2014-12-01

    Allergic contact dermatitis is an inflammatory skin disease (delayed type hypersensitivity reaction) that accounts for up to 20% of all childhood dermatitis. Allergic contact dermatitis represents a clinical manifestation of contact sensitization and usually occurs at skin sites that have come into contact with the allergen. The clinical features of allergic contact dermatitis are itchy eczematous lesions. Prevalence of contact sensitization varies between 27% and 96% of children with suspected contact dermatitis. The relationship between contact sensitization and atopic dermatitis has been widely discussed but only conflicting data have been reported. Epicutaneous patch testing is the gold standard for the diagnosis of allergic contact dermatitis. The most common allergens detected in children are: metals, topical medicaments, fragrances, and preservatives. The first line management of allergic contact dermatitis in children is to avoid the offending allergens identified with the patch test and a topical corticosteroid therapy.

  7. [Contact dermatitis from Agave americana].

    PubMed

    de la Cueva, Pablo; González-Carrascosa, Mateo; Campos, Minia; Leis, Vicente; Suárez, Ricardo; Lázaro, Pablo

    2005-10-01

    Numerous plant species and their derivatives can cause skin reactions through a variety of mechanisms: irritative contact dermatitis, allergic contact dermatitis, contact urticaria and photodermatitis. We present a case of irritative contact dermatitis after exposure to the sap of Agave americana. The skin symptoms in this case have only been described on rare occasions; although this condition usually presents with a papulovesicular rash, in this patient it appeared as purpuric lesions in the contact area.

  8. Contact Graph Routing

    NASA Technical Reports Server (NTRS)

    Burleigh, Scott C.

    2011-01-01

    Contact Graph Routing (CGR) is a dynamic routing system that computes routes through a time-varying topology of scheduled communication contacts in a network based on the DTN (Delay-Tolerant Networking) architecture. It is designed to enable dynamic selection of data transmission routes in a space network based on DTN. This dynamic responsiveness in route computation should be significantly more effective and less expensive than static routing, increasing total data return while at the same time reducing mission operations cost and risk. The basic strategy of CGR is to take advantage of the fact that, since flight mission communication operations are planned in detail, the communication routes between any pair of bundle agents in a population of nodes that have all been informed of one another's plans can be inferred from those plans rather than discovered via dialogue (which is impractical over long one-way-light-time space links). Messages that convey this planning information are used to construct contact graphs (time-varying models of network connectivity) from which CGR automatically computes efficient routes for bundles. Automatic route selection increases the flexibility and resilience of the space network, simplifying cross-support and reducing mission management costs. Note that there are no routing tables in Contact Graph Routing. The best route for a bundle destined for a given node may routinely be different from the best route for a different bundle destined for the same node, depending on bundle priority, bundle expiration time, and changes in the current lengths of transmission queues for neighboring nodes; routes must be computed individually for each bundle, from the Bundle Protocol agent's current network connectivity model for the bundle s destination node (the contact graph). Clearly this places a premium on optimizing the implementation of the route computation algorithm. The scalability of CGR to very large networks remains a research topic

  9. A deformation of AdS5 × S5

    NASA Astrophysics Data System (ADS)

    Gauntlett, Jerome P.; Gutowski, Jan B.; Suryanarayana, Nemani V.

    2004-11-01

    We analyse a one-parameter family of supersymmetric solutions of type IIB supergravity that includes AdS5 × S5. For small values of the parameter the solutions are causally well behaved, but beyond a critical value closed timelike curves (CTCs) appear. The solutions are holographically dual to {\\cal N}=4 supersymmetric Yang Mills theory on a non-conformally flat background with non-vanishing R-currents. We compute the holographic energy momentum tensor for the spacetime and show that it remains finite even when the CTCs appear. The solutions, as well as the uplift of some recently discovered AdS5 black-hole solutions, are shown to preserve precisely two supersymmetries.

  10. Supersymmetric AdS_6 solutions of type IIB supergravity

    NASA Astrophysics Data System (ADS)

    Kim, Hyojoong; Kim, Nakwoo; Suh, Minwoo

    2015-10-01

    We study the general requirement for supersymmetric AdS_6 solutions in type IIB supergravity. We employ the Killing spinor technique and study the differential and algebraic relations among various Killing spinor bilinears to find the canonical form of the solutions. Our result agrees precisely with the work of Apruzzi et al. (JHEP 1411:099, 2014), which used the pure spinor technique. Hoping to identify the geometry of the problem, we also computed four-dimensional theory through the dimensional reduction of type IIB supergravity on AdS_6. This effective action is essentially a non-linear sigma model with five scalar fields parametrizing {SL}(3,{R})/{SO}(2,1), modified by a scalar potential and coupled to Einstein gravity in Euclidean signature. We argue that the scalar potential can be explained by a subgroup CSO(1,1,1) subset {SL}(3,{R}) in a way analogous to gauged supergravity.

  11. Universal isolation in the AdS landscape

    NASA Astrophysics Data System (ADS)

    Danielsson, U. H.; Dibitetto, G.; Vargas, S. C.

    2016-12-01

    We study the universal conditions for quantum nonperturbative stability against bubble nucleation for pertubatively stable AdS vacua based on positive energy theorems. We also compare our analysis with the preexisting ones in the literature carried out within the thin-wall approximation. The aforementioned criterion is then tested in two explicit examples describing massive type IIA string theory compactified on S3 and S3×S3, respectively. The AdS landscape of both classes of compactifications is known to consist of a set of isolated points. The main result is that all critical points respecting the Breitenlohner-Freedman (BF) bound also turn out be stable at a nonperturbative level. Finally, we speculate on the possible universal features that may be extracted from the above specific examples.

  12. Tachyon inflation in an AdS braneworld with backreaction

    NASA Astrophysics Data System (ADS)

    Bilić, Neven; Dimitrijevic, Dragoljub D.; Djordjevic, Goran S.; Milosevic, Milan

    2017-02-01

    We analyze the inflationary scenario based on the tachyon field coupled with the radion of the second Randall-Sundrum model (RSII). The tachyon Lagrangian is derived from the dynamics of a 3-brane moving in the five-dimensional bulk. The AdS5 geometry of the bulk is extended to include the radion. Using the Hamiltonian formalism we find four nonlinear field equations supplemented by the modified Friedmann equations of the RSII braneworld cosmology. After a suitable rescaling we reduce the parameters of our model to only one free parameter related to the brane tension and the AdS5 curvature. We solve the equations numerically assuming a reasonably wide range of initial conditions determined by physical considerations. Varying the free parameter and initial conditions we confront our results with the Planck 2015 data.

  13. Ambitwistors, oscillators and massless fields on AdS5

    NASA Astrophysics Data System (ADS)

    Uvarov, D. V.

    2016-11-01

    Positive energy unitary irreducible representations of SU (2 , 2) can be constructed with the aid of bosonic oscillators in (anti)fundamental representation of SU(2)L × SU(2)R that are closely related to Penrose twistors. Starting with the correspondence between the doubleton representations, homogeneous functions on projective twistor space and on-shell generalized Weyl curvature SL (2 , C) spinors and their low-spin counterparts, we study in the similar way the correspondence between the massless representations, homogeneous functions on ambitwistor space and, via the Penrose transform, with the gauge fields on Minkowski boundary of AdS5. The possibilities of reconstructing massless fields on AdS5 and some applications are also discussed.

  14. Generalised structures for N=1 AdS backgrounds

    NASA Astrophysics Data System (ADS)

    Coimbra, André; Strickland-Constable, Charles

    2016-11-01

    We expand upon a claim made in a recent paper [arXiv:1411.5721] that generic minimally supersymmetric AdS backgrounds of warped flux compactifications of Type II and M theory can be understood as satisfying a straightforward weak integrability condition in the language of {E}_{d(d)}× {R}+ generalised geometry. Namely, they are spaces admitting a generalised G-structure set by the Killing spinor and with constant singlet generalised intrinsic torsion.

  15. On information loss in AdS3/CFT2

    DOE PAGES

    Fitzpatrick, A. Liam; Kaplan, Jared; Li, Daliang; ...

    2016-05-18

    We discuss information loss from black hole physics in AdS3, focusing on two sharp signatures infecting CFT2 correlators at large central charge c: ‘forbidden singularities’ arising from Euclidean-time periodicity due to the effective Hawking temperature, and late-time exponential decay in the Lorentzian region. We study an infinite class of examples where forbidden singularities can be resolved by non-perturbative effects at finite c, and we show that the resolution has certain universal features that also apply in the general case. Analytically continuing to the Lorentzian regime, we find that the non-perturbative effects that resolve forbidden singularities qualitatively change the behavior ofmore » correlators at times t ~SBH, the black hole entropy. This may resolve the exponential decay of correlators at late times in black hole backgrounds. By Borel resumming the 1/c expansion of exact examples, we explicitly identify ‘information-restoring’ effects from heavy states that should correspond to classical solutions in AdS3. Lastly, our results suggest a line of inquiry towards a more precise formulation of the gravitational path integral in AdS3.« less

  16. Shock Wave Collisions and Thermalization in AdS_5

    NASA Astrophysics Data System (ADS)

    Kovchegov, Y. V.

    We study heavy ion collisions at strong 't Hooft coupling usingAdS/CFT correspondence. According to the AdS/CFT dictionary heavy ion collisions correspond to gravitational shock wave collisions in AdS_5. We construct the metric in the forward light cone after the collision perturbatively through expansion of Einstein equations in graviton exchanges. We obtain an analytic expression for the metric including all-order graviton exchanges with one shock wave, while keeping the exchanges with another shock wave at the lowest order. We read off the corresponding energy-momentum tensor of the produced medium. Unfortunately this energy-momentum tensor does not correspond to ideal hydrodynamics, indicating that higher order graviton exchanges are needed to construct the full solution of the problem. We also show that shock waves must completely stop almost immediately after the collision in AdS_5, which, on the field theory side, corresponds to complete nuclear stopping due to strong coupling effects, likely leading to Landau hydrodynamics. Finally, we perform trapped surface analysis of the shock wave collisions demonstrating that a bulk black hole, corresponding to ideal hydrodynamics on the boundary, has to be created in such collisions, thus constructing a proof of thermalization in heavy ion collisions at strong coupling.

  17. Contact dynamics math model

    NASA Technical Reports Server (NTRS)

    Glaese, John R.; Tobbe, Patrick A.

    1986-01-01

    The Space Station Mechanism Test Bed consists of a hydraulically driven, computer controlled six degree of freedom (DOF) motion system with which docking, berthing, and other mechanisms can be evaluated. Measured contact forces and moments are provided to the simulation host computer to enable representation of orbital contact dynamics. This report describes the development of a generalized math model which represents the relative motion between two rigid orbiting vehicles. The model allows motion in six DOF for each body, with no vehicle size limitation. The rotational and translational equations of motion are derived. The method used to transform the forces and moments from the sensor location to the vehicles' centers of mass is also explained. Two math models of docking mechanisms, a simple translational spring and the Remote Manipulator System end effector, are presented along with simulation results. The translational spring model is used in an attempt to verify the simulation with compensated hardware in the loop results.

  18. Occupational protein contact dermatitis.

    PubMed

    Barbaud, Annick; Poreaux, Claire; Penven, Emmanuelle; Waton, Julie

    2015-01-01

    Occupational contact dermatitis is generally caused by haptens but can also be induced by proteins causing mainly immunological contact urticaria (ICU); chronic hand eczema in the context of protein contact dermatitis (PCD). In a monocentric retrospective study, from our database, only 31 (0.41%) of patients with contact dermatitis had positive skin tests with proteins: 22 had occupational PCD, 3 had non-occupational PCD, 5 occupational ICU and 1 cook had a neutrophilic fixed food eruption (NFFE) due to fish. From these results and analysis of literature, the characteristics of PCD can be summarized as follows. It is a chronic eczematous dermatitis, possibly exacerbated by work, suggestive if associated with inflammatory perionyxix and immediate erythema with pruritis, to be investigated when the patient resumes work after a period of interruption. Prick tests with the suspected protein-containing material are essential, as patch tests have negative results. In case of multisensitisation revealed by prick tests, it is advisable to analyse IgE against recombinant allergens. A history of atopy, found in 56 to 68% of the patients, has to be checked for. Most of the cases are observed among food-handlers but PCD can also be due to non-edible plants, latex, hydrolysed proteins or animal proteins. Occupational exposure to proteins can thus lead to the development of ICU. Reflecting hypersensitivity to very low concentrations of allergens, investigating ICU therefore requires caution and prick tests should be performed with a diluted form of the causative protein-containing product. Causes are food, especially fruit peel, non-edible plants, cosmetic products, latex, animals.

  19. Electron Device Contact Studies.

    DTIC Science & Technology

    1982-05-01

    from van der Pauw measurements ......................................... 110 5.2 M’odel of a MS contact with an interfacial oxide layer. 116 6.1 I-V...Process ............................ .76 4.3 Diffused Layer Data Determined from van der Pauw 77 Measurements... van der Pauw measurement was performed and a value of diffused layer sheet resistivity was obtained. Junction lapping and staining was then used to

  20. Metal Contacts in Semiconductors.

    DTIC Science & Technology

    1983-11-01

    surfaces, Pnotoelectron spe troscopy, Auger electron spectro- I scopy, Schottky barriers, ohmic contacts, Defects in semiconductors, Cadmium * telluride...Indium phosphide, Gallium arsenide, Gallium Selenide . j 20. ABSTR ACT (roothat ow rees esh " neceay and td..ity by block -. b*w) SThe application of...angstroms. Also, provided one eliminates the systems where cadmium outdiffusion into high work function metals occurs then good agreement between the

  1. Contact stress sensor

    DOEpatents

    Kotovsky, Jack [Oakland, CA

    2012-02-07

    A contact stress sensor includes one or more MEMS fabricated sensor elements, where each sensor element of includes a thin non-recessed portion, a recessed portion and a pressure sensitive element adjacent to the recessed portion. An electric circuit is connected to the pressure sensitive element. The circuit includes a thermal compensator and a pressure signal circuit element configured to provide a signal upon movement of the pressure sensitive element.

  2. Contact stress sensor

    DOEpatents

    Kotovsky, Jack

    2014-02-11

    A method for producing a contact stress sensor that includes one or more MEMS fabricated sensor elements, where each sensor element of includes a thin non-recessed portion, a recessed portion and a pressure sensitive element adjacent to the recessed portion. An electric circuit is connected to the pressure sensitive element. The circuit includes a pressure signal circuit element configured to provide a signal upon movement of the pressure sensitive element.

  3. Contact dermatitis in children

    PubMed Central

    2010-01-01

    Contact dermatitis in pediatric population is a common but (previously) under recognized disease. It is usually divided into the allergic and the irritant forms. The diagnosis is usually obtained with the patch test technique after conducting a thorough medical history and careful physical examination but patch testing in infants may be particularly difficult, and false-positive reactions may occur. This study also provides an overview of the most common allergens in pediatric population and discusses various therapeutic modalities. PMID:20205907

  4. 75 FR 51187 - Airworthiness Directives; Pratt & Whitney Canada Corp. (P&WC) PW305A and PW305B Turboprop Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-19

    ... change in the low-cycle fatigue lifing methodology for the IMI 834 material, the recommended service life... uncontained event and possible damage to the airplane. DATES: We must receive comments on this proposed AD by... states: As a result of a change in the low-cycle fatigue lifing methodology for the IMI 834 material,...

  5. 75 FR 52435 - Airworthiness Directives; Pratt & Whitney Canada (P&WC) PW530A, PW545A, and PW545B Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... Canada (P&WC) PW530A, PW545A, and PW545B Turbofan Engines AGENCY: Federal Aviation Administration (FAA...: Discussion Transport Canada, which is the aviation authority for Canada, has issued Canada Airworthiness... This AD This product has been approved by the aviation authority of Canada, and is approved...

  6. 75 FR 62319 - Airworthiness Directives; Pratt & Whitney JT8D-9, -9A, -11, -15, -17, and -17R Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-08

    ... root, which could result in uncontained failures of first stage fan blades and damage to the airplane.... The extension would allow time to determine the root cause of a fan blade failure on a Delta DC-9... rulemaking process. The root cause investigation can continue after the AD is issued. We did not change...

  7. Texas Community College Funding: Nonmetropolitan and Metropolitan Ad Valorem Tax Rates and Revenue

    ERIC Educational Resources Information Center

    Waller, Lee; Flannery, Joseph; Adams, Kenneth; Bowen, Stephen; Norvell, Kevin; Sherman, Suzanne; Watt, Jacqueline; Waller, Sharon

    2007-01-01

    This article examines ad valorem tax rates per $100 valuation and the resultant tax revenues per in-district contact hour for Texas nonmetropolitan and metropolitan public community colleges. The results of the analyses indicate no difference in ad valorem tax rates between these institutions but demonstrate differences in the resultant tax…

  8. Dual contact pogo pin assembly

    DOEpatents

    Hatch, Stephen McGarry

    2016-06-21

    A contact assembly includes a base and a pair of electrical contacts supported by the base. A first end of the first electrical contact corresponds to a first end of the base and is configured to engage a first external conductive circuit element. A first end of the second electrical contact also corresponds to the first end of the base and is configured to engage a second external conductive circuit element. The first contact and the second contact are electrically isolated from one another and configured to compress when engaging an external connector element. The base includes an aperture positioned on a second end of the base outboard of a second end of the first and second electrical contacts. The aperture presents a narrowing shape with a wide mouth distal the electrical contacts and a narrow internal through-hole proximate the electrical contacts.

  9. Dual contact pogo pin assembly

    DOEpatents

    Hatch, Stephen McGarry

    2015-01-20

    A contact assembly includes a base and a pair of electrical contacts supported by the base. A first end of the first electrical contact corresponds to a first end of the base and is configured to engage a first external conductive circuit element. A first end of the second electrical contact also corresponds to the first end of the base and is configured to engage a second external conductive circuit element. The first contact and the second contact are electrically isolated from one another and configured to compress when engaging an external connector element. The base includes an aperture positioned on a second end of the base outboard of a second end of the first and second electrical contacts. The aperture presents a narrowing shape with a wide mouth distal the electrical contacts and a narrow internal through-hole proximate the electrical contacts.

  10. The generalized added mass revised

    NASA Astrophysics Data System (ADS)

    De Wilde, Juray

    2007-05-01

    The reformulation of the generalized or apparent added mass presented by De Wilde [Phys. Fluids 17, 113304 (2005)] neglects the presence of a drag-type force in the gas and solid phase momentum equations. Reformulating the generalized added mass accounting for the presence of a drag-type force, an apparent drag force appears next to the apparent distribution of the filtered gas phase pressure gradient over the phases already found by De Wilde in the above-cited reference. The reformulation of the generalized added mass and the evaluation of a linear wave propagation speed test then suggest a generalized added mass type closure approach to completely describe filtered gas-solid momentum transfer, that is, including both the filtered drag force and the correlation between the solid volume fraction and the gas phase pressure gradient.

  11. AD-1 aircraft in flight

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The Ames-Dryden (AD)-1 was a research aircraft designed to investigate the concept of an oblique (or pivoting) wing. The movie clip runs about 17 seconds and has two air-to-air views of the AD-1. The first shot is from slightly above as the wing pivots to 60 degrees. The other angle is almost directly below the aircraft when the wing is fully pivoted.

  12. Contact dermatitis in printing tradesmen.

    PubMed

    Nethercott, J R; Nosal, R

    1986-05-01

    During a 2-year period in Toronto, Canada, 21 printing tradesmen with contact dermatitis were evaluated. 67% had allergic contact dermatitis; 29% due to ultraviolet-cured ink components. Irritant contact dermatitis accounted for 37% of the cases. The prognosis in printing tradesmen with contact dermatitis is guarded, except for those with allergic contact dermatitis due to UV-cured components, as the tradesmen who were sensitized to other contactants eventually left the trade. Offset lithography was associated with the problem in 18 of the 21 cases. A brief outline is given of the printing processes in common use.

  13. Euclidean and Noetherian entropies in AdS space

    SciTech Connect

    Dutta, Suvankar; Gopakumar, Rajesh

    2006-08-15

    We examine the Euclidean action approach, as well as that of Wald, to the entropy of black holes in asymptotically AdS spaces. From the point of view of holography these two approaches are somewhat complementary in spirit and it is not obvious why they should give the same answer in the presence of arbitrary higher derivative gravity corrections. For the case of the AdS{sub 5} Schwarzschild black hole, we explicitly study the leading correction to the Bekenstein-Hawking entropy in the presence of a variety of higher derivative corrections studied in the literature, including the Type IIB R{sup 4} term. We find a nontrivial agreement between the two approaches in every case. Finally, we give a general way of understanding the equivalence of these two approaches.

  14. 75 FR 50942 - Airworthiness Directives; Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... JT8D-7, -7A, -7B, -9, - 9A, -11, -15, -15A, -17, -17A, -17R, and -17AR Series Turbofan Engines AGENCY..., -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR series turbofan engines. That AD currently requires revisions to the engine manufacturer's time limits section (TLS) to...

  15. Adhesive Contact Sweeper

    NASA Technical Reports Server (NTRS)

    Patterson, Jonathan D.

    1993-01-01

    Adhesive contact sweeper removes hair and particles vacuum cleaner leaves behind, without stirring up dust. Also cleans loose rugs. Sweeper holds commercially available spools of inverted adhesive tape. Suitable for use in environments in which air kept free of dust; optics laboratories, computer rooms, and areas inhabited by people allergic to dust. For carpets, best used in tandem with vacuum cleaner; first pass with vacuum cleaner removes coarse particles, and second pass with sweeper extracts fine particles. This practice extends useful life of adhesive spools.

  16. Adhesion in hydrogel contacts.

    PubMed

    Torres, J R; Jay, G D; Kim, K-S; Bothun, G D

    2016-05-01

    A generalized thermomechanical model for adhesion was developed to elucidate the mechanisms of dissipation within the viscoelastic bulk of a hyperelastic hydrogel. Results show that in addition to the expected energy release rate of interface formation, as well as the viscous flow dissipation, the bulk composition exhibits dissipation due to phase inhomogeneity morphological changes. The mixing thermodynamics of the matrix and solvent determines the dynamics of the phase inhomogeneities, which can enhance or disrupt adhesion. The model also accounts for the time-dependent behaviour. A parameter is proposed to discern the dominant dissipation mechanism in hydrogel contact detachment.

  17. Adhesion in hydrogel contacts

    NASA Astrophysics Data System (ADS)

    Torres, J. R.; Jay, G. D.; Kim, K.-S.; Bothun, G. D.

    2016-05-01

    A generalized thermomechanical model for adhesion was developed to elucidate the mechanisms of dissipation within the viscoelastic bulk of a hyperelastic hydrogel. Results show that in addition to the expected energy release rate of interface formation, as well as the viscous flow dissipation, the bulk composition exhibits dissipation due to phase inhomogeneity morphological changes. The mixing thermodynamics of the matrix and solvent determines the dynamics of the phase inhomogeneities, which can enhance or disrupt adhesion. The model also accounts for the time-dependent behaviour. A parameter is proposed to discern the dominant dissipation mechanism in hydrogel contact detachment.

  18. Contact dermatitis to methylisothiazolinone*

    PubMed Central

    Scherrer, Maria Antonieta Rios; Rocha, Vanessa Barreto; Andrade, Ana Regina Coelho

    2015-01-01

    Methylisothiazolinone (MI) is a preservative found in cosmetic and industrial products. Contact dermatitis caused by either methylchloroisothiazolinone/methylisothiazolinone (MCI/MI or Kathon CG) or MI has shown increasing frequency. The latter is preferably detected through epicutaneous testing with aqueous MI 2000 ppm, which is not included in the Brazilian standard tray. We describe a series of 23 patients tested using it and our standard tray. A case with negative reaction to MCI/MI and positive to MI is emphasized. PMID:26734880

  19. Contact dermatitis in Nigeria.

    PubMed

    Olumide, Y M

    1985-05-01

    Nickel is the most important sensitizer in Lagos, with an incidence of 12.3% of 453 patients tested. There was no sex difference, as the wearing of necklaces and bracelets was equally fashionable among both sexes. Housewife eczema is not common, probably because of hardening. Dermatitis from additives in the processing of leather and rubber footwear was the next most common. Chromate sensitivity comes usually from leather or cement. Cultural and climatic factors are mainly responsible for differences in the incidence of contact dermatitis found in Lagos from other countries.

  20. Contact Control, Version 1

    SciTech Connect

    von Sternberg, Alex

    2016-07-21

    The contact control code is a generalized force control scheme meant to interface with a robotic arm being controlled using the Robot Operating System (ROS). The code allows the user to specify a control scheme for each control dimension in a way that many different control task controllers could be built from the same generalized controller. The input to the code includes maximum velocity, maximum force, maximum displacement, and a control law assigned to each direction and the output is a 6 degree of freedom velocity command that is sent to the robot controller.

  1. New Features in ADS Labs

    NASA Astrophysics Data System (ADS)

    Accomazzi, Alberto; Kurtz, M. J.; Henneken, E. A.; Grant, C. S.; Thompson, D.; Di Milia, G.; Luker, J.; Murray, S. S.

    2013-01-01

    The NASA Astrophysics Data System (ADS) has been working hard on updating its services and interfaces to better support our community's research needs. ADS Labs is a new interface built on the old tried-and-true ADS Abstract Databases, so all of ADS's content is available through it. In this presentation we highlight the new features that have been developed in ADS Labs over the last year: new recommendations, metrics, a citation tool and enhanced fulltext search. ADS Labs has long been providing article-level recommendations based on keyword similarity, co-readership and co-citation analysis of its corpus. We have now introduced personal recommendations, which provide a list of articles to be considered based on a individual user's readership history. A new metrics interface provides a summary of the basic impact indicators for a list of records. These include the total and normalized number of papers, citations, reads, and downloads. Also included are some of the popular indices such as the h, g and i10 index. The citation helper tool allows one to submit a set of records and obtain a list of top 10 papers which cite and/or are cited by papers in the original list (but which are not in it). The process closely resembles the network approach of establishing "friends of friends" via an analysis of the citation network. The full-text search service now covers more than 2.5 million documents, including all the major astronomy journals, as well as physics journals published by Springer, Elsevier, the American Physical Society, the American Geophysical Union, and all of the arXiv eprints. The full-text search interface interface allows users and librarians to dig deep and find words or phrases in the body of the indexed articles. ADS Labs is available at http://adslabs.org

  2. Contact Lenses in the Laboratory.

    ERIC Educational Resources Information Center

    Kingston, David W.

    1981-01-01

    Summarizes results of a three-item questionnaire returned by 43 Michigan institutions expressing views on wearing contact lenses in chemical laboratories. Questions focused on eye protection, type of protection, and use of contact lenses. (SK)

  3. Heavy quark potential from deformed AdS5 models

    NASA Astrophysics Data System (ADS)

    Zhang, Zi-qiang; Hou, De-fu; Chen, Gang

    2017-04-01

    In this paper, we investigate the heavy quark potential in some holographic QCD models. The calculation relies on a modified renormalization scheme mentioned in a previous work of Albacete et al. After studying the heavy quark potential in Pirner-Galow model and Andreev-Zakharov model, we extend the discussion to a general deformed AdS5 case. It is shown that the obtained potential is negative definite for all quark-antiquark separations, differs from that using the usual renormalization scheme.

  4. The AdS central charge in string theory

    NASA Astrophysics Data System (ADS)

    Troost, Jan

    2011-11-01

    We evaluate the vacuum expectation value of the central charge operator in string theory in an AdS3 vacuum. Our calculation provides a rare non-zero one-point function on a spherical worldsheet. The evaluation involves the regularization both of a worldsheet ultraviolet divergence (associated to the infinite volume of the conformal Killing group), and a space-time infrared divergence (corresponding to the infinite volume of space-time). The two divergences conspire to give a finite result, which is the classical general relativity value for the central charge, corrected in bosonic string theory by an infinite series of tree level higher derivative terms.

  5. Internal structure of charged AdS black holes

    NASA Astrophysics Data System (ADS)

    Bhattacharjee, Srijit; Sarkar, Sudipta; Virmani, Amitabh

    2016-06-01

    When an electrically charged black hole is perturbed, its inner horizon becomes a singularity, often referred to as the Poisson-Israel mass inflation singularity. Ori constructed a model of this phenomenon for asymptotically flat black holes, in which the metric can be determined explicitly in the mass inflation region. In this paper we implement the Ori model for charged AdS black holes. We find that the mass function inflates faster than the flat space case as the inner horizon is approached. Nevertheless, the mass inflation singularity is still a weak singularity: Although spacetime curvature becomes infinite, tidal distortions remain finite on physical objects attempting to cross it.

  6. Introducing ADS 2.0

    NASA Astrophysics Data System (ADS)

    Accomazzi, Alberto; Kurtz, M. J.; Henneken, E. A.; Grant, C. S.; Thompson, D.; Luker, J.; Chyla, R.; Murray, S. S.

    2014-01-01

    In the spring of 1993, the Smithsonian/NASA Astrophysics Data System (ADS) first launched its bibliographic search system. It was known then as the ADS Abstract Service, a component of the larger Astrophysics Data System effort which had developed an interoperable data system now seen as a precursor of the Virtual Observatory. As a result of the massive technological and sociological changes in the field of scholarly communication, the ADS is now completing the most ambitious technological upgrade in its twenty-year history. Code-named ADS 2.0, the new system features: an IT platform built on web and digital library standards; a new, extensible, industrial strength search engine; a public API with various access control capabilities; a set of applications supporting search, export, visualization, analysis; a collaborative, open source development model; and enhanced indexing of content which includes the full-text of astronomy and physics publications. The changes in the ADS platform affect all aspects of the system and its operations, including: the process through which data and metadata are harvested, curated and indexed; the interface and paradigm used for searching the database; and the follow-up analysis capabilities available to the users. This poster describes the choices behind the technical overhaul of the system, the technology stack used, and the opportunities which the upgrade is providing us with, namely gains in productivity and enhancements in our system capabilities.

  7. Polyurethane toilet seat contact dermatitis.

    PubMed

    Turan, Hakan; Saricaoğlu, Hayriye; Turan, Ayşegül; Tunali, Sükran

    2011-01-01

    Polyurethane chemicals are produced by the reaction of isocyanates and they may cause allergic contact dermatitis or precipitate asthma attacks. Contact dermatitis to polyurethane toilet seat has not been reported before. Herein we present a case of allergic contact dermatitis to polyurethane toilet seat.

  8. Contact position sensor using constant contact force control system

    NASA Technical Reports Server (NTRS)

    Sturdevant, Jay (Inventor)

    1995-01-01

    A force control system (50) and method are provided for controlling a position contact sensor (10) so as to produce a constant controlled contact force therewith. The system (50) includes a contact position sensor (10) which has a contact probe (12) for contacting the surface of a target to be measured and an output signal (V.sub.o) for providing a position indication thereof. An actuator (30) is provided for controllably driving the contact position sensor (10) in response to an actuation control signal (I). A controller (52) receives the position indication signal (V.sub.o) and generates in response thereto the actuation control signal (I) so as to provide a substantially constant selective force (F) exerted by the contact probe (12). The actuation drive signal (I) is generated further in response to substantially linear approximation curves based on predetermined force and position data attained from the sensor (10) and the actuator (30).

  9. Dynamic contact angle analysis of silicone hydrogel contact lenses.

    PubMed

    Read, Michael Leonard; Morgan, Philip Bruce; Kelly, Jeremiah Michael; Maldonado-Codina, Carole

    2011-07-01

    Contact angle measurements are used to infer the clinical wetting characteristics of contact lenses. Such characterization has become more commonplace since the introduction of silicone hydrogel contact lens materials, which have been associated with reduced in vivo wetting due to the inclusion of siloxane-containing components. Using consistent methodology and a single investigator, advancing and receding contact angles were measured for 11 commercially available silicone hydrogel contact lens types with a dynamic captive bubble technique employing customized, fully automated image analysis. Advancing contact angles were found to range between 20° and 72° with the lenses falling into six statistically discrete groupings. Receding contact angles fell within a narrower range, between 17° and 22°, with the lenses segregated into three groups. The relationship between these laboratory measurements and the clinical performance of the lenses requires further investigation.

  10. Primordial fluctuations from complex AdS saddle points

    SciTech Connect

    Hertog, Thomas; Woerd, Ellen van der E-mail: ellen@itf.fys.kuleuven.be

    2016-02-01

    One proposal for dS/CFT is that the Hartle-Hawking (HH) wave function in the large volume limit is equal to the partition function of a Euclidean CFT deformed by various operators. All saddle points defining the semiclassical HH wave function in cosmology have a representation in which their interior geometry is part of a Euclidean AdS domain wall with complex matter fields. We compute the wave functions of scalar and tensor perturbations around homogeneous isotropic complex saddle points, turning on single scalar field matter only. We compare their predictions for the spectra of CMB perturbations with those of a different dS/CFT proposal based on the analytic continuation of inflationary universes to real asymptotically AdS domain walls. We find the predictions of both bulk calculations agree to first order in the slow roll parameters, but there is a difference at higher order which, we argue, is a signature of the HH state of the fluctuations.

  11. Conserved charges in timelike warped AdS3 spaces

    NASA Astrophysics Data System (ADS)

    Donnay, L.; Fernández-Melgarejo, J. J.; Giribet, G.; Goya, A.; Lavia, E.

    2015-06-01

    We consider the timelike version of warped anti-de Sitter space (WAdS), which corresponds to the three-dimensional section of the Gödel solution of four-dimensional cosmological Einstein equations. This geometry presents closed timelike curves (CTCs), which are inherited from its four-dimensional embedding. In three dimensions, this type of solution can be supported without matter provided the graviton acquires mass. Here, among the different ways to consistently give mass to the graviton in three dimensions, we consider the parity-even model known as new massive gravity (NMG). In the bulk of timelike WAdS3 space, we introduce defects that, from the three-dimensional point of view, represent spinning massive particlelike objects. For this type of source, we investigate the definition of quasilocal gravitational energy as seen from infinity, far beyond the region where the CTCs appear. We also consider the covariant formalism applied to NMG to compute the mass and the angular momentum of spinning particlelike defects and compare the result with the one obtained by means of the quasilocal stress tensor. We apply these methods to special limits in which the WAdS3 solutions coincide with locally AdS3 and locally AdS2×R spaces. Finally, we make some comments about the asymptotic symmetry algebra of asymptotically WAdS3 spaces in NMG.

  12. AdS nonlinear instability: moving beyond spherical symmetry

    NASA Astrophysics Data System (ADS)

    Dias, Óscar J. C.; Santos, Jorge E.

    2016-12-01

    Anti-de Sitter (AdS) is conjectured to be nonlinear unstable to a weakly turbulent mechanism that develops a cascade towards high frequencies, leading to black hole formation (Dafermos and Holzegel 2006 Seminar at DAMTP (University of Cambridge) available at https://dpmms.cam.ac.uk/~md384/ADSinstability.pdf, Bizon and Rostworowski 2011 Phys. Rev. Lett. 107 031102). We give evidence that the gravitational sector of perturbations behaves differently from the scalar one studied by Bizon and Rostworowski. In contrast with Bizon and Rostworowski, we find that not all gravitational normal modes of AdS can be nonlinearly extended into periodic horizonless smooth solutions of the Einstein equation. In particular, we show that even seeds with a single normal mode can develop secular resonances, unlike the spherically symmetric scalar field collapse studied by Bizon and Rostworowski. Moreover, if the seed has two normal modes, more than one resonance can be generated at third order, unlike the spherical collapse of Bizon and Rostworowski. We also show that weak turbulent perturbative theory predicts the existence of direct and inverse cascades, with the former dominating the latter for equal energy two-mode seeds.

  13. Contact sensing from force measurements

    NASA Technical Reports Server (NTRS)

    Bicchi, Antonio; Salisbury, J. K.; Brock, David L.

    1993-01-01

    This article addresses contact sensing (i.e., the problem of resolving the location of a contact, the force at the interface, and the moment about the contact normals). Called 'intrinsic' contact sensing for the use of internal force and torque measurements, this method allows for practical devices that provide simple, relevant contact information in practical robotic applications. Such sensors have been used in conjunction with robot hands to identify objects, determine surface friction, detect slip, augment grasp stability, measure object mass, probe surfaces, and control collision and for a variety of other useful tasks. This article describes the theoretical basis for their operation and provides a framework for future device design.

  14. Equilibrium contact angle or the most-stable contact angle?

    PubMed

    Montes Ruiz-Cabello, F J; Rodríguez-Valverde, M A; Cabrerizo-Vílchez, M A

    2014-04-01

    It is well-established that the equilibrium contact angle in a thermodynamic framework is an "unattainable" contact angle. Instead, the most-stable contact angle obtained from mechanical stimuli of the system is indeed experimentally accessible. Monitoring the susceptibility of a sessile drop to a mechanical stimulus enables to identify the most stable drop configuration within the practical range of contact angle hysteresis. Two different stimuli may be used with sessile drops: mechanical vibration and tilting. The most stable drop against vibration should reveal the changeless contact angle but against the gravity force, it should reveal the highest resistance to slide down. After the corresponding mechanical stimulus, once the excited drop configuration is examined, the focus will be on the contact angle of the initial drop configuration. This methodology needs to map significantly the static drop configurations with different stable contact angles. The most-stable contact angle, together with the advancing and receding contact angles, completes the description of physically realizable configurations of a solid-liquid system. Since the most-stable contact angle is energetically significant, it may be used in the Wenzel, Cassie or Cassie-Baxter equations accordingly or for the surface energy evaluation.

  15. Reducing contact resistance in graphene devices through contact area patterning.

    PubMed

    Smith, Joshua T; Franklin, Aaron D; Farmer, Damon B; Dimitrakopoulos, Christos D

    2013-04-23

    Performance of graphene electronics is limited by contact resistance associated with the metal-graphene (M-G) interface, where unique transport challenges arise as carriers are injected from a 3D metal into a 2D-graphene sheet. In this work, enhanced carrier injection is experimentally achieved in graphene devices by forming cuts in the graphene within the contact regions. These cuts are oriented normal to the channel and facilitate bonding between the contact metal and carbon atoms at the graphene cut edges, reproducibly maximizing "edge-contacted" injection. Despite the reduction in M-G contact area caused by these cuts, we find that a 32% reduction in contact resistance results in Cu-contacted, two-terminal devices, while a 22% reduction is achieved for top-gated graphene transistors with Pd contacts as compared to conventionally fabricated devices. The crucial role of contact annealing to facilitate this improvement is also elucidated. This simple approach provides a reliable and reproducible means of lowering contact resistance in graphene devices to bolster performance. Importantly, this enhancement requires no additional processing steps.

  16. Contact angle and local wetting at contact line.

    PubMed

    Li, Ri; Shan, Yanguang

    2012-11-06

    This theoretical study was motivated by recent experiments and theoretical work that had suggested the dependence of the static contact angle on the local wetting at the triple-phase contact line. We revisit this topic because the static contact angle as a local wetting parameter is still not widely understood and clearly known. To further clarify the relationship of the static contact angle with wetting, two approaches are applied to derive a general equation for the static contact angle of a droplet on a composite surface composed of heterogeneous components. A global approach based on the free surface energy of a thermodynamic system containing the droplet and solid surface shows the static contact angle as a function of local surface chemistry and local wetting state at the contact line. A local approach, in which only local forces acting on the contact line are considered, results in the same equation. The fact that the local approach agrees with the global approach further demonstrates the static contact angle as a local wetting parameter. Additionally, the study also suggests that the wetting described by the Wenzel and Cassie equations is also the local wetting of the contact line rather than the global wetting of the droplet.

  17. Point contacts in encapsulated graphene

    SciTech Connect

    Handschin, Clevin; Fülöp, Bálint; Csonka, Szabolcs; Makk, Péter; Blanter, Sofya; Weiss, Markus; Schönenberger, Christian; Watanabe, Kenji; Taniguchi, Takashi

    2015-11-02

    We present a method to establish inner point contacts with dimensions as small as 100 nm on hexagonal boron nitride (hBN) encapsulated graphene heterostructures by pre-patterning the top-hBN in a separate step prior to dry-stacking. 2- and 4-terminal field effect measurements between different lead combinations are in qualitative agreement with an electrostatic model assuming point-like contacts. The measured contact resistances are 0.5–1.5 kΩ per contact, which is quite low for such small contacts. By applying a perpendicular magnetic field, an insulating behaviour in the quantum Hall regime was observed, as expected for inner contacts. The fabricated contacts are compatible with high mobility graphene structures and open up the field for the realization of several electron optical proposals.

  18. Electron Device Contact Studies.

    DTIC Science & Technology

    1980-08-01

    resistance of the contact Barrier height (I-V or C-V method) I-V characteristic Auger spectroscopy analysis will be made in an attempt to relate the atomic ...in the n-type layer can be given as [20]. C(x) = Cs erfc (25) where D = diffusion coefficient of the dopant atom in GaAs t = time of diffusion Cs...tunneling, assuming a uniform doping of C givess 2cs (IT)I ! 2(12) (8.85) (10 -14) W u (.6)(oI)(loT B (0.9 - 0) W 3.5 x 10-6 cm. The actual Sn atom doping

  19. Contact allergy to dimethacrylate.

    PubMed

    Vaswani, Ravi; Kim, Soon Ja; Sanchez, Adrian; Vaswani, Surender

    2012-01-01

    Contact allergy to methacrylates is uncommon. We present a 55-year-old woman with a 10-year history of persistent pruritus and burning sensation of the gums every time she wore her dentures. Initially she developed swelling and erythema of the face soon after the dentures were placed on the gums. These symptoms abated after a barrier liner was applied between her gums and the dentures. However, the burning sensation and pruritus of the gums progressively worsened and she started to develop blisters on the gums. The skin allergen patch test was 3+ positive with erythema, edema, papules, ulceration, and pruritus for the denture component dimethacrylate. The diagnosis was supported by the patient's medical history, notably positive patch test, and complete amelioration of the symptoms upon cessation of dimethacrylate denture usage.

  20. Contact dermatitis to Alstroemeria.

    PubMed

    Santucci, B; Picardo, M; Iavarone, C; Trogolo, C

    1985-04-01

    A study was carried out on 50 workers in a floriculture centre to evaluate the incidence of contact dermatitis to Alstroemeria. 3 subjects gave positive reactions to aqueous and ethanolic extracts of cut flowers, stems and leaves. By column chromatography, the allergen was isolated and its chemical structure identified as 6-tuliposide A by proton magnetic resonance and carbon-13 magnetic resonance. Only 6-tuliposide A was isolated from cut flowers, and this gave positive reactions when patch tested at 0.01%; a-methylene-gamma-butyrolactone at 10(-5) (v/v) was positive in the same 3 subjects. Other lactones (gamma-methylene-gamma-butyrolactone, alantolactone, isoalantolactone) were negative at all concentrations used.

  1. Separating Growth from Value Added

    ERIC Educational Resources Information Center

    Yeagley, Raymond

    2007-01-01

    This article discusses Rochester's two academic models that offer different tools for different purposes--measuring individual learning and measuring what affects learning. The main focus of currently available growth measures is formative assessment--providing data to inform instructional planning. Value-added assessment is not a student…

  2. Adding Value to Indiana's Commodities.

    ERIC Educational Resources Information Center

    Welch, Mary A., Ed.

    1995-01-01

    Food processing plants are adding value to bulk and intermediate products to sell overseas. The Asian Pacific Rim economies constituted the largest market for consumer food products in 1993. This shift toward consumer food imports in this area is due to more women working outside the home, the internationalization of populations, and dramatic…

  3. Courtship American Style: Newspaper Ads

    ERIC Educational Resources Information Center

    Cameron, Catherine; And Others

    1977-01-01

    This study investigated an increasing social phenomenon--newspaper advertising for dating or marital partners--in terms of the bargaining process involved. Content analysis of personal ads in a popular "respectable" singles newspaper revealed a pattern of offers and requests reminiscent of a heterosexual stock market. (Author)

  4. An investigation of AdS2 backreaction and holography

    NASA Astrophysics Data System (ADS)

    Engelsöy, Julius; Mertens, Thomas G.; Verlinde, Herman

    2016-07-01

    We investigate a dilaton gravity model in AdS2 proposed by Almheiri and Polchinski [1] and develop a 1d effective description in terms of a dynamical boundary time with a Schwarzian derivative action. We show that the effective model is equivalent to a 1d version of Liouville theory, and investigate its dynamics and symmetries via a standard canonical framework. We include the coupling to arbitrary conformal matter and analyze the effective action in the presence of possible sources. We compute commutators of local operators at large time separation, and match the result with the time shift due to a gravitational shockwave interaction. We study a black hole evaporation process and comment on the role of entropy in this model.

  5. Supersymmetry Properties of AdS Supergravity Backgrounds

    NASA Astrophysics Data System (ADS)

    Beck, Samuel; Gutowski, Jan; Papadopoulos, George

    2017-01-01

    Anti-de Sitter supergravity backgrounds are of particular interest in light of the AdS/CFT correspondence, which relates them to dual conformal field theories on the boundary of the anti-de Sitter space. We have investigated the forms of the supersymmetries these backgrounds preserve by solving the Killing spinor equations on the anti-de Sitter components of these spaces. We have found that a supersymmetric AdSn background necessarily preserves 2⌊n/2⌋ k supersymmetries for n <= 4 and 2 ⌊n/2 ⌋ + 1 k supersymmetries for 4 < n <= 7 , k ∈N> 0 . Additionally, we have found that the Killing spinors of each background are exactly the zeroes of a Dirac-like operator constructed from the Killing spinor equations.

  6. The Massive Wave Equation in Asymptotically AdS Spacetimes

    NASA Astrophysics Data System (ADS)

    Warnick, C. M.

    2013-07-01

    We consider the massive wave equation on asymptotically AdS spaces. We show that the timelike F behaves like a finite timelike boundary, on which one may impose the equivalent of Dirichlet, Neumann or Robin conditions for a range of (negative) mass parameter which includes the conformally coupled case. We demonstrate well posedness for the associated initial-boundary value problems at the H 1 level of regularity. We also prove that higher regularity may be obtained, together with an asymptotic expansion for the field near F. The proofs rely on energy methods, tailored to the modified energy introduced by Breitenlohner and Freedman. We do not assume the spacetime is stationary, nor that the wave equation separates.

  7. On jordanian deformations of AdS5 and supergravity

    NASA Astrophysics Data System (ADS)

    Hoare, Ben; van Tongeren, Stijn J.

    2016-10-01

    We consider various homogeneous Yang-Baxter deformations of the {{AdS}}5× {{{S}}}5 superstring that can be obtained from the η-deformed superstring and related models by singular boosts. The jordanian deformations we obtain in this way behave similarly to the η-deformed model with regard to supergravity: T dualizing the classical sigma model it is possible to find corresponding solutions of supergravity, which, however, have dilatons that prevent T dualizing back. Hence the backgrounds of these jordanian deformations are not solutions of supergravity. Still, they do satisfy a set of recently found modified supergravity equations which implies that the corresponding sigma models are scale invariant. The abelian models that we obtain by singular boosts do directly correspond to solutions of supergravity. In addition to our main results we consider contraction limits of our main example, which do correspond to supergravity solutions.

  8. Aspects of warped AdS3/CFT2 correspondence

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Zhang, Jia-Ju; Zhang, Jian-Dong; Zhong, De-Liang

    2013-04-01

    In this paper we apply the thermodynamics method to investigate the holographic pictures for the BTZ black hole, the spacelike and the null warped black holes in three-dimensional topologically massive gravity (TMG) and new massive gravity (NMG). Even though there are higher derivative terms in these theories, the thermodynamics method is still effective. It gives consistent results with the ones obtained by using asymptotical symmetry group (ASG) analysis. In doing the ASG analysis we develop a brute-force realization of the Barnich-Brandt-Compere formalism with Mathematica code, which also allows us to calculate the masses and the angular momenta of the black holes. In particular, we propose the warped AdS3/CFT2 correspondence in the new massive gravity, which states that quantum gravity in the warped spacetime could holographically dual to a two-dimensional CFT with {c_R}={c_L}=24 /{Gm{β^2√{{2( {21-4{β^2}} )}}}}.

  9. Wireless Measurement of Contact and Motion Between Contact Surfaces

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Taylor, Bryant D.

    2007-01-01

    This method uses a magnetic-field- response contact sensor that is designed to identify surface contact and motion between contact locations. The sensor has three components: (1) a capacitor-inductor circuit with two sets of electrical contact pads, (2) a capacitor with a set of electrical contact pads, and (3) an inductor with a set of electrical contact pads. A unique feature of this sensor is that it is inherently multifunctional. Information can be derived from analyzing such sensor response attributes as amplitude, frequency, and bandwidth. A change in one attribute can be due to a change in a physical property of a system. A change in another attribute can be due to another physical property, which has no relationship to the first one.

  10. Systematics of Coupling Flows in AdS Backgrounds

    SciTech Connect

    Goldberger, Walter D.; Rothstein, Ira Z.

    2003-03-18

    We give an effective field theory derivation, based on the running of Planck brane gauge correlators, of the large logarithms that arise in the predictions for low energy gauge couplings in compactified AdS}_5 backgrounds, including the one-loop effects of bulk scalars, fermions, and gauge bosons. In contrast to the case of charged scalars coupled to Abelian gauge fields that has been considered previously in the literature, the one-loop corrections are not dominated by a single 4D Kaluza-Klein mode. Nevertheless, in the case of gauge field loops, the amplitudes can be reorganized into a leading logarithmic contribution that is identical to the running in 4D non-Abelian gauge theory, and a term which is not logarithmically enhanced and is analogous to a two-loop effect in 4D. In a warped GUT model broken by the Higgs mechanism in the bulk,we show that the matching scale that appears in the large logarithms induced by the non-Abelian gauge fields is m_{XY}^2/k where m_{XY} is the bulk mass of the XY bosons and k is the AdS curvature. This is in contrast to the UV scale in the logarithmic contributions of scalars, which is simply the bulk mass m. Our results are summarized in a set of simple rules that can be applied to compute the leading logarithmic predictions for coupling constant relations within a given warped GUT model. We present results for both bulk Higgs and boundary breaking of the GUT gauge

  11. Holography beyond conformal invariance and AdS isometry?

    SciTech Connect

    Barvinsky, A. O.

    2015-03-15

    We suggest that the principle of holographic duality be extended beyond conformal invariance and AdS isometry. Such an extension is based on a special relation between functional determinants of the operators acting in the bulk and on its boundary, provided that the boundary operator represents the inverse propagators of the theory induced on the boundary by the Dirichlet boundary value problem in the bulk spacetime. This relation holds for operators of a general spin-tensor structure on generic manifolds with boundaries irrespective of their background geometry and conformal invariance, and it apparently underlies numerous O(N{sup 0}) tests of the AdS/CFT correspondence, based on direct calculation of the bulk and boundary partition functions, Casimir energies, and conformal anomalies. The generalized holographic duality is discussed within the concept of the “double-trace” deformation of the boundary theory, which is responsible in the case of large-N CFT coupled to the tower of higher-spin gauge fields for the renormalization group flow between infrared and ultraviolet fixed points. Potential extension of this method beyond the one-loop order is also briefly discussed.

  12. Hysteresis during contact angles measurement.

    PubMed

    Diaz, M Elena; Fuentes, Javier; Cerro, Ramon L; Savage, Michael D

    2010-03-15

    A theory, based on the presence of an adsorbed film in the vicinity of the triple contact line, provides a molecular interpretation of intrinsic hysteresis during the measurement of static contact angles. Static contact angles are measured by placing a sessile drop on top of a flat solid surface. If the solid surface has not been previously in contact with a vapor phase saturated with the molecules of the liquid phase, the solid surface is free of adsorbed liquid molecules. In the absence of an adsorbed film, molecular forces configure an advancing contact angle larger than the static contact angle. After some time, due to an evaporation/adsorption process, the interface of the drop coexists with an adsorbed film of liquid molecules as part of the equilibrium configuration, denoted as the static contact angle. This equilibrium configuration is metastable because the droplet has a larger vapor pressure than the surrounding flat film. As the drop evaporates, the vapor/liquid interface contracts and the apparent contact line moves towards the center of the drop. During this process, the film left behind is thicker than the adsorbed film and molecular attraction results in a receding contact angle, smaller than the equilibrium contact angle.

  13. Evolution of the low contact stress (LCS) complete knee system.

    PubMed

    Crossett, Larry

    2006-09-01

    The low contact stress knee design was one of the first designs to become widely available and popular for total knee arthroplasty. The low contact stress knee was initially designed to address wear due to high contact stresses seen in fixed-bearing designs. Today, nearly 30 years after its introduction, the technology behind the knee remains just as relevant. Many of the original innovations in early low contact stress knee systems are still in use today. New innovations, like a new instrument set and the advent of computer-assisted surgery, have added to the success of the technology. The history of this innovative design is discussed with special consideration given to the specific design principals that have improved the basic design over the past three decades.

  14. Contact dermatitis: allergic and irritant.

    PubMed

    Tan, Cher-Han; Rasool, Sarah; Johnston, Graham A

    2014-01-01

    Facial contact dermatitis is frequently encountered in medical practice in both male and female patients. Identifying the underlying cause can be challenging, and the causative agent may be overlooked if it is not considered during the assessment of a patient. The two main types of contact dermatitis are irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD). The mechanisms and common causative agents vary for both ICD and ACD, but the clinical picture is often similar, particularly for chronic disease. Facial contact dermatitis can be successfully treated by avoiding the causative agent. In this review, we focus on the clinical assessment of a patient with facial contact dermatitis and the mechanisms of both ICD and ACD. Common causative agents, including emerging allergens, are discussed in detail, and suggestions are made regarding the management of patients with proven ICD or ACD of the face.

  15. Wearable telescopic contact lens.

    PubMed

    Arianpour, Ashkan; Schuster, Glenn M; Tremblay, Eric J; Stamenov, Igor; Groisman, Alex; Legerton, Jerry; Meyers, William; Amigo, Goretty Alonso; Ford, Joseph E

    2015-08-20

    We describe the design, fabrication, and testing of a 1.6 mm thick scleral contact lens providing both 1× and 2.8× magnified vision paths, intended for use as a switchable eye-borne telescopic low-vision aid. The F/9.7 telescopic vision path uses an 8.2 mm diameter annular entrance pupil and 4 internal reflections in a polymethyl methacrylate precision optic. This gas-impermeable insert is contained inside a smooth outer casing of rigid gas-permeable polymer, which also provides achromatic correction for refraction at the curved lens face. The unmagnified F/4.1 vision path is through the central aperture of the lens, with additional transmission between the annular telescope rings to enable peripheral vision. We discuss potential solutions for providing oxygenation for an extended wear version of the lens. The prototype lenses were characterized using a scale-model human eye, and telescope functionality was confirmed in a small-scale clinical (nondispensed) demonstration.

  16. Realizing "value-added" metrology

    NASA Astrophysics Data System (ADS)

    Bunday, Benjamin; Lipscomb, Pete; Allgair, John; Patel, Dilip; Caldwell, Mark; Solecky, Eric; Archie, Chas; Morningstar, Jennifer; Rice, Bryan J.; Singh, Bhanwar; Cain, Jason; Emami, Iraj; Banke, Bill, Jr.; Herrera, Alfredo; Ukraintsev, Vladamir; Schlessinger, Jerry; Ritchison, Jeff

    2007-03-01

    The conventional premise that metrology is a "non-value-added necessary evil" is a misleading and dangerous assertion, which must be viewed as obsolete thinking. Many metrology applications are key enablers to traditionally labeled "value-added" processing steps in lithography and etch, such that they can be considered integral parts of the processes. Various key trends in modern, state-of-the-art processing such as optical proximity correction (OPC), design for manufacturability (DFM), and advanced process control (APC) are based, at their hearts, on the assumption of fine-tuned metrology, in terms of uncertainty and accuracy. These trends are vehicles where metrology thus has large opportunities to create value through the engineering of tight and targetable process distributions. Such distributions make possible predictability in speed-sorts and in other parameters, which results in high-end product. Additionally, significant reliance has also been placed on defect metrology to predict, improve, and reduce yield variability. The necessary quality metrology is strongly influenced by not only the choice of equipment, but also the quality application of these tools in a production environment. The ultimate value added by metrology is a result of quality tools run by a quality metrology team using quality practices. This paper will explore the relationships among present and future trends and challenges in metrology, including equipment, key applications, and metrology deployment in the manufacturing flow. Of key importance are metrology personnel, with their expertise, practices, and metrics in achieving and maintaining the required level of metrology performance, including where precision, matching, and accuracy fit into these considerations. The value of metrology will be demonstrated to have shifted to "key enabler of large revenues," debunking the out-of-date premise that metrology is "non-value-added." Examples used will be from critical dimension (CD

  17. Noise of sliding rough contact

    NASA Astrophysics Data System (ADS)

    Le Bot, Alain

    2017-01-01

    This article is a discussion about the origin of friction noise produced when rubbing solids having rough surfaces. We show that noise emerges from numerous impacts into the contact between antagonist asperities of surfaces. Prediction of sound sources reduces to a statistical problem of contact mechanics. On the other hand, contact is also responsible of dissipation of vibration. This leads to the paradoxical result that the noise may not be proportional to the number of sources.

  18. Point contact silicon solar cells

    NASA Technical Reports Server (NTRS)

    Swanson, Richard M.

    1987-01-01

    A new type of silicon solar cell has been developed. It is called the point-contact cell because the metal semiconductor contacts are restricted to an array of small points on the back of the cell. The point contact cell has recently demonstrated 22 percent conversion efficiency at one sun and 27.5 percent at 100 suns under an AM1.5 spectrum.

  19. [Occlusal contact principles in prosthodontics].

    PubMed

    Wang, Meiqing

    2012-12-01

    The occlusion contact, which is engaged in many dental clinical scopes, is the primary subject in the field of dental occlusion. Prosthodontics is one of the fields that are involved in with this subject, including the static relation (the occlusal contacts in intercuspal occlusion) and the dynamic relation (such as that in chewing movement). Not only the restorations, but also the abutments, that have to be properly managed to obtain a harmony occlusal contact relationship.

  20. Method for forming metal contacts

    DOEpatents

    Reddington, Erik; Sutter, Thomas C; Bu, Lujia; Cannon, Alexandra; Habas, Susan E; Curtis, Calvin J; Miedaner, Alexander; Ginley, David S; Van Hest, Marinus Franciscus Antonius Maria

    2013-09-17

    Methods of forming metal contacts with metal inks in the manufacture of photovoltaic devices are disclosed. The metal inks are selectively deposited on semiconductor coatings by inkjet and aerosol apparatus. The composite is heated to selective temperatures where the metal inks burn through the coating to form an electrical contact with the semiconductor. Metal layers are then deposited on the electrical contacts by light induced or light assisted plating.

  1. Ohmic Contacts to Semiconducting Diamond

    DTIC Science & Technology

    1990-10-01

    after approxi- mately 30 minutes. Analysis using Auger electron spectroscopy, scanning electron microscopy, and x-ray diffraction established the...adherent wire bonds. To test the contacts for bondability, 10-mil gold wires were bonded to the contacts by using an ultrasonic ball bonder. Pull-to...resistance of the ohmic contacts (reference 4). We have chosen to use the circular transmission line geometry and analysis first proposed by Reeves

  2. Scattering States in AdS/CFT

    SciTech Connect

    Fitzpatrick, A.Liam; Kaplan, Jared; /SLAC

    2012-02-14

    We show that suitably regulated multi-trace primary states in large N CFTs behave like 'in' and 'out' scattering states in the flat-space limit of AdS. Their transition matrix elements approach the exact scattering amplitudes for the bulk theory, providing a natural CFT definition of the flat space S-Matrix. We study corrections resulting from the AdS curvature and particle propagation far from the center of AdS, and show that AdS simply provides an IR regulator that disappears in the flat space limit.

  3. Electrical contact resistance in filaments

    NASA Astrophysics Data System (ADS)

    Wu, Xiang-Fa; Zhou, Zhengping; Zhou, Wang-Min

    2012-05-01

    Electrical contact resistance (ECR) influences the electrochemical performance of porous electrodes made of stacked discrete materials (e.g., carbon nanotubes, nanofibers, etc.) for use in supercapacitors and rechargeable batteries. This study establishes a simple elasticity-conductivity model for the ECR of filaments in adhesive contact. The elastic deformation and size of electrical contact zone of the filaments are determined by using an adhesive contact model of filaments, and the ECR of adhesive filaments is obtained in explicit form. Dependencies of the ECR upon the filament geometries, surface energy, and elasticity are examined.

  4. Ion Implanted Passivated Contacts for Interdigitated Back Contacted Solar Cells

    SciTech Connect

    Young, David L.; Nemeth, William; LaSalvia, Vincenzo; Reedy, Robert; Bateman, Nicholas; Stradins, Pauls

    2015-06-14

    We describe work towards an interdigitated back contacted (IBC) solar cell utilizing ion implanted, passivated contacts. Formation of electron and hole passivated contacts to n-type CZ wafers using tunneling SiO2 and ion implanted amorphous silicon (a-Si) are described. P and B were ion implanted into intrinsic amorphous Si films at several doses and energies. A series of post-implant anneals showed that the passivation quality improved with increasing annealing temperatures up to 900 degrees C. The recombination parameter, Jo, as measured by a Sinton lifetime tester, was Jo ~ 14 fA/cm2 for Si:P, and Jo ~ 56 fA/cm2 for Si:B contacts. The contact resistivity for the passivated contacts, as measured by TLM patterns, was 14 milliohm-cm2 for the n-type contact and 0.6 milliohm-cm2 for the p-type contact. These Jo and pcontact values are encouraging for forming IBC cells using ion implantation to spatially define dopants.

  5. Contact line and contact angle dynamics in superhydrophobic channels.

    PubMed

    Zhang, Junfeng; Kwok, Daniel Y

    2006-05-23

    The dynamics of the wetting and movement of a three-phase contact line confined between two superhydrophobic surfaces were studied using a mean-field free-energy lattice Boltzmann model. Principle features of superhydrophobic surfaces, such as trapped vapor/air between rough microstructures, high contact angles, reduced contact angle hysteresis, and low resistance to fluid flow, were all observed. Movement of the three-phase contact line over a well-patterned superhydrophobic surface displays a periodic stick-jump-slip behavior, while the dynamic contact angle changes accordingly from maximum to minimum. Two regimes were found for the flow velocity as a function of surface roughness and can be related directly to the balance between driving force and flow resistance. This work provides a better understanding of dynamic wetting and fluid flow behaviors over superhydrophobic surfaces and hence could be useful in related applications.

  6. Stability of charged global AdS4 spacetimes

    NASA Astrophysics Data System (ADS)

    Arias, Raúl; Mas, Javier; Serantes, Alexandre

    2016-09-01

    We study linear and nonlinear stability of asymptotically AdS4 solutions in Einstein-Maxwell-scalar theory. After summarizing the set of static solutions we first examine thermodynamical stability in the grand canonical ensemble and the phase transitions that occur among them. In the second part of the paper we focus on nonlinear stability in the microcanonical ensemble by evolving radial perturbations numerically. We find hints of an instability corner for vanishingly small perturbations of the same kind as the ones present in the uncharged case. Collapses are avoided, instead, if the charge and mass of the perturbations come to close the line of solitons. Finally we examine the soliton solutions. The linear spectrum of normal modes is not resonant and instability turns on at extrema of the mass curve. Linear stability extends to nonlinear stability up to some threshold for the amplitude of the perturbation. Beyond that, the soliton is destroyed and collapses to a hairy black hole. The relative width of this stability band scales down with the charge Q, and does not survive the blow up limit to a planar geometry.

  7. AdS4/CFT3 squashed, stretched and warped

    NASA Astrophysics Data System (ADS)

    Klebanov, Igor R.; Klose, Thomas; Murugan, Arvind

    2009-03-01

    We use group theoretic methods to calculate the spectrum of short multiplets around the extremum of Script N = 8 gauged supergravity potential which possesses Script N = 2 supersymmetry and SU(3) global symmetry. Upon uplifting to M-theory, it describes a warped product of AdS4 and a certain squashed and stretched 7-sphere. We find quantum numbers in agreement with those of the gauge invariant operators in the Script N = 2 superconformal Chern-Simons theory recently proposed to be the dual of this M-theory background. This theory is obtained from the U(N) × U(N) theory through deforming the superpotential by a term quadratic in one of the superfields. To construct this model explicitly, one needs to employ monopole operators whose complete understanding is still lacking. However, for the U(2) × U(2) gauge theory we make a proposal for the form of the monopole operators which has a number of desired properties. In particular, this proposal implies enhanced symmetry of the U(2) × U(2) ABJM theory for k = 1,2; it makes its similarity to and subtle difference from the BLG theory quite explicit.

  8. The ADS All Sky Survey

    NASA Astrophysics Data System (ADS)

    Goodman, Alyssa

    We will create the first interactive sky map of astronomers' understanding of the Universe over time. We will accomplish this goal by turning the NASA Astrophysics Data System (ADS), widely known for its unrivaled value as a literature resource, into a data resource. GIS and GPS systems have made it commonplace to see and explore information about goings-on on Earth in the context of maps and timelines. Our proposal shows an example of a program that lets a user explore which countries have been mentioned in the New York Times, on what dates, and in what kinds of articles. By analogy, the goal of our project is to enable this kind of exploration-on the sky-for the full corpus of astrophysical literature available through ADS. Our group's expertise and collaborations uniquely position us to create this interactive sky map of the literature, which we call the "ADS All-Sky Survey." To create this survey, here are the principal steps we need to follow. First, by analogy to "geotagging," we will "astrotag," the ADS literature. Many "astrotags" effectively already exist, thanks to curation efforts at both CDS and NED. These efforts have created links to "source" positions on the sky associated with each of the millions of articles in the ADS. Our collaboration with ADS and CDS will let us automatically extract astrotags for all existing and future ADS holdings. The new ADS Labs, which our group helps to develop, includes the ability for researchers to filter article search results using a variety of "facets" (e.g. sources, keywords, authors, observatories, etc.). Using only extracted astrotags and facets, we can create functionality like what is described in the Times example above: we can offer a map of the density of positions' "mentions" on the sky, filterable by the properties of those mentions. Using this map, researchers will be able to interactively, visually, discover what regions have been studied for what reasons, at what times, and by whom. Second, where

  9. Molecular dynamics study of contact mechanics: contact area and interfacial separation from small to full contact

    NASA Astrophysics Data System (ADS)

    Yang, Chunyan; Persson, Bo

    2008-03-01

    We report a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. We study the contact area and the interfacial separation from small contact (low load) to full contact (high load). For small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load [1-4]. For high load the contact area approaches to the nominal contact area (i.e., complete contact), and the interfacial separation approaches to zero. The present results may be very important for soft solids, e.g., rubber, or for very smooth surfaces, where complete contact can be reached at moderate high loads without plastic deformation of the solids. References: [1] C. Yang and B.N.J. Persson, arXiv:0710.0276, (to appear in Phys. Rev. Lett.) [2] B.N.J. Persson, Phys. Rev. Lett. 99, 125502 (2007) [3] L. Pei, S. Hyun, J.F. Molinari and M.O. Robbins, J. Mech. Phys. Sol. 53, 2385 (2005) [4] M. Benz, K.J. Rosenberg, E.J. Kramer and J.N. Israelachvili, J. Phy. Chem. B.110, 11884 (2006)

  10. Contact modeling for robotics applications

    SciTech Connect

    Lafarge, R.A.; Lewis, C.

    1998-08-01

    At Sandia National Laboratories (SNL), the authors are developing the ability to accurately predict motions for arbitrary numbers of bodies of arbitrary shapes experiencing multiple applied forces and intermittent contacts. In particular, the authors are concerned with the simulation of systems such as part feeders or mobile robots operating in realistic environments. Preliminary investigation of commercial dynamics software packages led them to the conclusion that they could use commercial software to provide everything they needed except for the contact model. They found that ADAMS best fit their needs for a simulation package. To simulate intermittent contacts, they need collision detection software that can efficiently compute the distances between non-convex objects and return the associated witness features. They also require a computationally efficient contact model for rapid simulation of impact, sustained contact under load, and transition to and from contact conditions. This paper provides a technical review of a custom hierarchical distance computation engine developed at Sandia, called the C-Space Toolkit (CSTk). In addition, they describe an efficient contact model using a non-linear damping term developed by SNL and Ohio State. Both the CSTk and the non-linear damper have been incorporated in a simplified two-body testbed code, which is used to investigate how to correctly model the contact using these two utilities. They have incorporated this model into the ADAMS software using the callable function interface. An example that illustrates the capabilities of the 9.02 release of ADAMS with their extensions is provided.

  11. Fabricating customized hydrogel contact lens

    NASA Astrophysics Data System (ADS)

    Childs, Andre; Li, Hao; Lewittes, Daniella M.; Dong, Biqin; Liu, Wenzhong; Shu, Xiao; Sun, Cheng; Zhang, Hao F.

    2016-10-01

    Contact lenses are increasingly used in laboratories for in vivo animal retinal imaging and pre-clinical studies. The lens shapes often need modification to optimally fit corneas of individual test subjects. However, the choices from commercially available contact lenses are rather limited. Here, we report a flexible method to fabricate customized hydrogel contact lenses. We showed that the fabricated hydrogel is highly transparent, with refractive indices ranging from 1.42 to 1.45 in the spectra range from 400 nm to 800 nm. The Young’s modulus (1.47 MPa) and hydrophobicity (with a sessile drop contact angle of 40.5°) have also been characterized experimentally. Retinal imaging using optical coherence tomography in rats wearing our customized contact lenses has the quality comparable to the control case without the contact lens. Our method could significantly reduce the cost and the lead time for fabricating soft contact lenses with customized shapes, and benefit the laboratorial-used contact lenses in pre-clinical studies.

  12. Fabricating customized hydrogel contact lens

    PubMed Central

    Childs, Andre; Li, Hao; Lewittes, Daniella M.; Dong, Biqin; Liu, Wenzhong; Shu, Xiao; Sun, Cheng; Zhang, Hao F.

    2016-01-01

    Contact lenses are increasingly used in laboratories for in vivo animal retinal imaging and pre-clinical studies. The lens shapes often need modification to optimally fit corneas of individual test subjects. However, the choices from commercially available contact lenses are rather limited. Here, we report a flexible method to fabricate customized hydrogel contact lenses. We showed that the fabricated hydrogel is highly transparent, with refractive indices ranging from 1.42 to 1.45 in the spectra range from 400 nm to 800 nm. The Young’s modulus (1.47 MPa) and hydrophobicity (with a sessile drop contact angle of 40.5°) have also been characterized experimentally. Retinal imaging using optical coherence tomography in rats wearing our customized contact lenses has the quality comparable to the control case without the contact lens. Our method could significantly reduce the cost and the lead time for fabricating soft contact lenses with customized shapes, and benefit the laboratorial-used contact lenses in pre-clinical studies. PMID:27748361

  13. Forcing contact inhibition of locomotion.

    PubMed

    Roycroft, Alice; Mayor, Roberto

    2015-07-01

    Contact inhibition of locomotion drives a variety of biological phenomenon, from cell dispersion to collective cell migration and cancer invasion. New imaging techniques have allowed contact inhibition of locomotion to be visualised in vivo for the first time, helping to elucidate some of the molecules and forces involved in this phenomenon.

  14. Fabricating customized hydrogel contact lens.

    PubMed

    Childs, Andre; Li, Hao; Lewittes, Daniella M; Dong, Biqin; Liu, Wenzhong; Shu, Xiao; Sun, Cheng; Zhang, Hao F

    2016-10-17

    Contact lenses are increasingly used in laboratories for in vivo animal retinal imaging and pre-clinical studies. The lens shapes often need modification to optimally fit corneas of individual test subjects. However, the choices from commercially available contact lenses are rather limited. Here, we report a flexible method to fabricate customized hydrogel contact lenses. We showed that the fabricated hydrogel is highly transparent, with refractive indices ranging from 1.42 to 1.45 in the spectra range from 400 nm to 800 nm. The Young's modulus (1.47 MPa) and hydrophobicity (with a sessile drop contact angle of 40.5°) have also been characterized experimentally. Retinal imaging using optical coherence tomography in rats wearing our customized contact lenses has the quality comparable to the control case without the contact lens. Our method could significantly reduce the cost and the lead time for fabricating soft contact lenses with customized shapes, and benefit the laboratorial-used contact lenses in pre-clinical studies.

  15. Contact dermatitis in military personnel.

    PubMed

    Dever, Tara T; Walters, Michelle; Jacob, Sharon

    2011-01-01

    Military personnel encounter the same allergens and irritants as their civilian counterparts and are just as likely to develop contact dermatitis from common exposures encountered in everyday life. In addition, they face some unique exposures that can be difficult to avoid owing to their occupational duties. Contact dermatitis can be detrimental to a military member's career if he or she is unable to perform core duties or avoid the inciting substances. An uncontrolled contact dermatitis can result in the member's being placed on limited-duty (ie, nondeployable) status, needing a job or rate change, or separation from military service. We present some common causes of contact dermatitis in military personnel worldwide and some novel sources of contact dermatitis in this population that may not be intuitive.

  16. The inside outs of AdS3/CFT2: exact AdS wormholes with entangled CFT duals

    NASA Astrophysics Data System (ADS)

    Mandal, Gautam; Sinha, Ritam; Sorokhaibam, Nilakash

    2015-01-01

    We present the complete family of solutions of 3D gravity (Λ < 0) with two asymptotically AdS exterior regions. The solutions are constructed from data at the two boundaries, which correspond to two independent and arbitrary stress tensors T R , , and T L , . The two exteriors are smoothly joined on to an interior region through a regular horizon. We find CFT duals of these geometries which are entangled states of two CFT's. We compute correlators between general operators at the two boundaries and find perfect agreement between CFT and bulk calculations. We calculate and match the CFT entanglement entropy (EE) with the holographic EE which involves geodesics passing through the wormhole. We also compute a holographic, non-equilibrium entropy for the CFT using properties of the regular horizon. The construction of the bulk solutions here uses an exact version of Brown-Henneaux type diffeomorphisms which are asymptotically nontrivial and transform the CFT states by two independent unitary operators on the two sides. Our solutions provide an infinite family of explicit examples of the ER=EPR relation of Maldacena and Susskind [1].

  17. Elastohydrodynamic lubrication of elliptical contacts

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1981-01-01

    The determination of the minimum film thickness within contact is considered for both fully flooded and starved conditions. A fully flooded conjunction is one in which the film thickness is not significantly changed when the amount of lubricant is increased. The fully flooded results presented show the influence of contact geometry on minimum film thickness as expressed by the ellipticity parameter and the dimensionless speed, load, and materials parameters. These results are applied to materials of high elastic modulus (hard EHL), such as metal, and to materials of low elastic modulus(soft EHL), such as rubber. In addition to the film thickness equations that are developed, contour plots of pressure and film thickness are given which show the essential features of elastohydrodynamically lubricated conjunctions. The crescent shaped region of minimum film thickness, with its side lobes in which the separation between the solids is a minimum, clearly emerges in the numerical solutions. In addition to the 3 presented for the fully flooded results, 15 more cases are used for hard EHL contacts and 18 cases are used for soft EHL contacts in a theoretical study of the influence of lubricant starvation on film thickness and pressure. From the starved results for both hard and soft EHL contacts, a simple and important dimensionless inlet boundary distance is specified. This inlet boundary distance defines whether a fully flooded or a starved condition exists in the contact. Contour plots of pressure and film thickness in and around the contact are shown for conditions.

  18. Microdroplet evaporation with a forced pinned contact line.

    PubMed

    Gleason, Kevin; Putnam, Shawn A

    2014-09-02

    Experimental and numerical investigations of water microdroplet evaporation on heated, laser patterned polymer substrates are reported. The study is focused on both (i) controlling a droplet's contact line dynamics during evaporation to identifying how the contact line influences evaporative heat transfer and (ii) validating numerical simulations with experimental data. Droplets are formed on the polymer surface using a bottom-up methodology, where a computer-controlled syringe pump feeds water through a 200 μm diameter fluid channel within the heated polymer substrate. This methodology facilitates precise control of the droplet's growth rate, size, and inlet temperature. In addition to this microchannel supply line, the substrate surfaces are laser patterned with a moatlike trench around the fluid-channel outlet, adding additional control of the droplet's contact line motion, area, and contact angle. In comparison to evaporation on a nonpatterned polymer surface, the laser patterned trench increases contact line pinning time by ∼60% of the droplet's lifetime. Numerical simulations of diffusion controlled evaporation are compared the experimental data with a pinned contact line. These diffusion based simulations consistently over predict the droplet's evaporation rate. In efforts to improve this model, a temperature distribution along the droplet's liquid-vapor interface is imposed to account for the concentration distribution of saturated vapor along the interface, which yields improved predictions within 2-4% of the experimental data throughout the droplet's lifetime on heated substrates.

  19. Dynamic contact angles in oil-aqueous polymer solutions.

    PubMed

    Al-Shareef, Amer; Neogi, P; Bai, Baojun

    2017-01-25

    Polymer flooding is an important process in enhanced oil recovery. The displacement front is unstable when low viscosity brine displaces the heavy crude oil in the reservoir. Water-soluble polymers are added to the brine to increase its viscosity which stabilizes the displacement process. To analyze the displacement process at the micro-level, we have investigated the dynamic contact angles in silicone oil-polymer (polyethylene oxide) solution and for the first time. The dynamic contact angle is the apparent contact angle at the three-phase contact line which governs the capillary pressure, and thus is important for the displacement process. The data show no obvious signs of either shear thinning or elastic behavior, although for some systems with highest elastic effects some unexplained effects on dynamic contact angles are observed that correlate with elastic effects. Overall, dynamic contact angles are explained well using existing models for two Newtonian fluids, when the zero shear viscosity is used for the polymer solution.

  20. Modular and hierarchical structure of social contact networks

    NASA Astrophysics Data System (ADS)

    Ge, Yuanzheng; Song, Zhichao; Qiu, Xiaogang; Song, Hongbin; Wang, Yong

    2013-10-01

    Social contact networks exhibit overlapping qualities of communities, hierarchical structure and spatial-correlated nature. We propose a mixing pattern of modular and growing hierarchical structures to reconstruct social contact networks by using an individual’s geospatial distribution information in the real world. The hierarchical structure of social contact networks is defined based on the spatial distance between individuals, and edges among individuals are added in turn from the modular layer to the highest layer. It is a gradual process to construct the hierarchical structure: from the basic modular model up to the global network. The proposed model not only shows hierarchically increasing degree distribution and large clustering coefficients in communities, but also exhibits spatial clustering features of individual distributions. As an evaluation of the method, we reconstruct a hierarchical contact network based on the investigation data of a university. Transmission experiments of influenza H1N1 are carried out on the generated social contact networks, and results show that the constructed network is efficient to reproduce the dynamic process of an outbreak and evaluate interventions. The reproduced spread process exhibits that the spatial clustering of infection is accordant with the clustering of network topology. Moreover, the effect of individual topological character on the spread of influenza is analyzed, and the experiment results indicate that the spread is limited by individual daily contact patterns and local clustering topology rather than individual degree.

  1. Wraparound-contact solar cells

    NASA Technical Reports Server (NTRS)

    Baraona, C. R.; Klucher, T. M.; Thornhill, J. W.; Scott-Monck, J.

    1979-01-01

    Positive and negative electrical contacts are on back surface of wraparound-contact solar cell. With both terminals on nonilluminated side, cells can be connected back-to-back, and interconnection of many cells can be automated by using printed-circuit techniques. Cells are made by screen-printing layer of dielectric around edge of cell and extending top contact over dielectric to back surface. Wraparound also facilitates application of transparent covers and encapsulants. Efficiencies of cells are in excess of seventeen percent.

  2. Contact Pressure and Shear Stress Analysis on Conforming Contact Problem

    NASA Astrophysics Data System (ADS)

    Nagatani, Haruo; Imou, Akitoshi

    Two methods to solve a conforming contact problem are proposed. First method is general and can be applicable to the contact case between elastic arbitrary shape bodies. For verification FEA is performed on the convex-concave sphere contact, and the result of this method is well corresponding to the FEA result. However, the accuracy deteriorates when the mesh aspect ratio is extremely large. This phenomenon is caused by the usage of numerical integration for the calculation of influence coefficient. The second method is devised to avoid this problem, while this improved method is applicable only to the case when the contact area can be considered to be on a cylinder surface. By using this method, the contact pressure can be obtained without the deterioration even in the case of edge load occurring between ball bearing race shoulder and ball. The results of the contact pressure and the shear stress that is necessary for bearing life estimation are compared with the FEA result, which showed well correspondence.

  3. AD, the ALICE diffractive detector

    NASA Astrophysics Data System (ADS)

    Tello, Abraham Villatoro

    2017-03-01

    ALICE is one of the four large experiments at the CERN Large Hadron Collider (LHC). As a complement to its Heavy-Ion physics program, ALICE started during Run 1 of LHC an extensive program dedicated to the study of proton-proton diffractive processes. In order to optimize its trigger efficiencies and purities in selecting diffractive events, the ALICE Collaboration installed a very forward AD detector during the Long Shut Down 1 of LHC. This new forward detector system consists of two stations made of two layers of scintillator pads, one station on each side of the interaction point. With this upgrade, ALICE has substantially increased its forward physics coverage, including the double rapidity gap based selection of central production, as well as the measurements of inclusive diffractive cross sections.

  4. High Dk piggyback contact lens system for contact lens-intolerant keratoconus patients

    PubMed Central

    Sengor, Tomris; Kurna, Sevda Aydin; Aki, Suat; Özkurt, Yelda

    2011-01-01

    Background: The aim of the study was to examine the clinical success of high Dk (oxygen permeability) piggyback contact lens (PBCL) systems for the correction of contact lens intolerant keratoconus patients. Methods: Sixteen patients (29 eyes) who were not able to wear gas-permeable rigid lenses were included in this study. Hyper Dk silicone hydrogel (oxygen transmissibility or Dk/t = 150 units) and fluorosilicone methacrylate copolymer (Dk/t = 100 units) lenses were chosen as the PBCL systems. The clinical examinations included visual acuity and corneal observation by biomicroscopy, keratometer reading, and fluorescein staining before and after fitting the PBCL system. Results: Indications for using PBCL system were: lens stabilization and comfort, improving comfort, and adding protection to the cone. Visual acuities increased significantly in all of the patients compared with spectacles (P = 0). Improvement in visual acuity compared with rigid lenses alone was recorded in 89.7% of eyes and no alteration of the visual acuity was observed in 10.3% of the eyes. Wearing time of PBCL systems for most of the patients was limited time (mean 6 months, range 3–12 months); thereafter they tolerated rigid lenses alone except for 2 patients. Conclusion: The PBCL system is a safe and effective method to provide centering and corneal protection against mechanical trauma by the rigid lenses for keratoconus patients and may increase contact lens tolerance. PMID:21468342

  5. Medical management of contact dermatitis.

    PubMed

    Alexandroff, A B; Johnston, G A

    2009-10-01

    Allergic and irritant contact dermatitis are important dermatological problems. Although the frequencies of positive reactions to a number of allergens have decreased during last 30 years because of better avoidance (and at least in part due to improved legislation), contact allergy to other agents is rising. The medical treatment starts from a correct identification of triggers of contact dermatitis which could allow patients to reduce or avoid exposure to these agents in future. A good clinical history, examination and immunological tests including patch testing are of crucial importance at this stage. Further management includes emollients, topical and oral corticosteroids, topical calcineurin inhibitors, azathioprine and ciclosporin. Methotrexate and alitretinoin are recent additions to the armamentarium of dermatologists who manage contact dermatitis.

  6. EPA Alternative Dispute Resolution Contacts

    EPA Pesticide Factsheets

    The success of EPA's ADR efforts depends on a network of talented and experienced professionals in Headquarters offices and EPA Regions. For Agency-wide ADR information, please contact the Conflict Prevention and Resolution Center.

  7. Transition metal contacts to graphene

    SciTech Connect

    Politou, Maria De Gendt, Stefan; Heyns, Marc; Asselberghs, Inge; Radu, Iuliana; Conard, Thierry; Richard, Olivier; Martens, Koen; Huyghebaert, Cedric; Tokei, Zsolt; Lee, Chang Seung; Sayan, Safak

    2015-10-12

    Achieving low resistance contacts to graphene is a common concern for graphene device performance and hybrid graphene/metal interconnects. In this work, we have used the circular Transfer Length Method (cTLM) to electrically characterize Ag, Au, Ni, Ti, and Pd as contact metals to graphene. The consistency of the obtained results was verified with the characterization of up to 72 cTLM structures per metal. Within our study, the noble metals Au, Ag and Pd, which form a weaker bond with graphene, are shown to result in lower contact resistance (Rc) values compared to the more reactive Ni and Ti. X-ray Photo Electron Spectroscopy and Transmission Electron Microscopy characterization for the latter have shown the formation of Ti and Ni carbides. Graphene/Pd contacts show a distinct intermediate behavior. The weak carbide formation signature and the low Rc values measured agree with theoretical predictions of an intermediate state of weak chemisorption of Pd on graphene.

  8. Racial Disparity in Police Contacts

    PubMed Central

    Crutchfield, Robert D.; Haggerty, Kevin P.; McGlynn, Anne; Catalano, Richard F.

    2013-01-01

    Criminologists agree the race disparity in arrests cannot be fully explained by differences in criminal behavior. We examine social environment factors that may lead to racial differences in police contact in early adolescence, including family, peers, school, and community. Data are from 331 8th-grade students. Blacks were almost twice as likely as Whites to report a police contact. Blacks reported more property crime but not more violent crime than Whites. Police contacts were increased by having a parent who had been arrested, a sibling involved in criminal activity, higher observed reward for negative behavior, having school disciplinary actions, and knowing adults who engaged in substance abuse or criminal behavior. Race differences in police contacts were partially attributable to more school discipline. PMID:24363956

  9. Pose and motion from contact

    SciTech Connect

    Jia, Y.B.; Erdmann, M.

    1999-05-01

    In the absence of vision, grasping an object often relies on tactile feedback from the fingertips. As the finger pushes the object, the fingertip can feel the contact point move. If the object is known in advance, from this motion the finger may infer the location of the contact point on the object, and thereby, the object pose. This paper primarily investigates the problem of determining the pose (orientation and position) and motion (velocity and angular velocity) of a planar object with known geometry from such contact motion generated by pushing. A dynamic analysis of pushing yields a nonlinear system that relates through contact the object pose and motion to the finger motion. The contact motion on the fingertip thus encodes certain information about the object pose. Nonlinear observability theory is employed to show that such information is sufficient for the finger to observe not only the pose, but also the motion of the object. Therefore, a sensing strategy can be realized as an observer of the nonlinear dynamic system. Two observers are subsequently introduced. The first observer, based on the work of Gautheir, Hammouri, and Othman (1992), has its gain determined by the solution of a Lyapunov-like equation; it can be activated at any time instant during a push. The second observer, based on Newton`s method, solves for the initial (motionless) object pose from three intermediate contact points during a push. Under the Coulomb-friction model, the paper deals with support friction in the plane and/or contact friction between the finger and the object. Extensive simulations have been done to demonstrate the feasibility of the two observers. Preliminary experiments (with an Adept robot) have also been conducted. A contact sensor has been implemented using strain gauges.

  10. Method for lubricating contacting surfaces

    DOEpatents

    Dugger, Michael T [Tijeras, NM; Ohlhausen, James A [Albuquerque, NM; Asay, David B [Boalsburg, PA; Kim, Seong H [State College, PA

    2011-12-06

    A method is provided for tribological lubrication of sliding contact surfaces, where two surfaces are in contact and in motion relative to each other, operating in a vapor-phase environment containing at least one alcohol compound at a concentration sufficiently high to provide one monolayer of coverage on at least one of the surfaces, where the alcohol compound continuously reacts at the surface to provide lubrication.

  11. [Contact lens care and maintenance].

    PubMed

    Bloise, L

    2017-03-29

    All contact lenses with replacement schedules longer than daily must be maintained. At each step of their use, the lenses may be contaminated. Contact lens solutions perform the essential functions of cleaning, decontaminating and preserving the lenses to prevent infectious problems and improve wearing comfort. Contact lens contamination essentially comes from hands, cleaning solutions, cases, water and the environment. The pathogenic microorganisms are mainly Gram-negative bacteria, fungi and amoebae. Contact lens deposits may or may not have an organic origin. Their presence increases the risk of infection because they serve as a nutrient matrix for microbes, and they are responsible for wearing discomfort. Contact lens solutions differ in their composition, their mechanism of action and the concentration of the various agents. To prescribe the best lens care system to each wearer and for each material, it is necessary to be very familiar with them. Maintenance is the main cause of discomfort with contact lenses, either through improper use, solution-material incompatibility, or a reaction of the wearer to the components.

  12. RF Sputtering of Gold Contacts On Niobium

    NASA Technical Reports Server (NTRS)

    Barr, D. W.

    1983-01-01

    Reliable gold contacts are deposited on niobium by combination of RF sputtering and photolithography. Process results in structures having gold only where desired for electrical contact. Contacts are stable under repeated cycling from room temperature to 4.2 K and show room-temperature contact resistance as much as 40 percent below indium contacts made by thermalcompression bonding.

  13. Solar cell with back side contacts

    SciTech Connect

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J; Wanlass, Mark Woodbury; Clews, Peggy J

    2013-12-24

    A III-V solar cell is described herein that includes all back side contacts. Additionally, the positive and negative electrical contacts contact compoud semiconductor layers of the solar cell other than the absorbing layer of the solar cell. That is, the positive and negative electrical contacts contact passivating layers of the solar cell.

  14. Contact Lens-Related Eye Infections

    MedlinePlus

    ... Stories Español Eye Health / Eye Health A-Z Contact Lens-Related Eye Infections Sections Contact Lens-Related ... About Contact Lenses Proper Care of Contact Lenses Contact Lens-Related Eye Infections Written by: Kierstan Boyd ...

  15. Measuring The Contact Resistances Of Photovoltaic Cells

    NASA Technical Reports Server (NTRS)

    Burger, D. R.

    1985-01-01

    Simple method devised to measure contact resistances of photovoltaic solar cells. Method uses readily available equipment and applicable at any time during life of cell. Enables evaluation of cell contact resistance, contact-end resistance, contact resistivity, sheet resistivity, and sheet resistivity under contact.

  16. Crane-Load Contact Sensor

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert; Mata, Carlos; Cox, Robert

    2005-01-01

    An electronic instrument has been developed as a prototype of a portable crane-load contact sensor. Such a sensor could be helpful in an application in which the load rests on a base in a horizontal position determined by vertical alignment pins (see Figure 1). If the crane is not positioned to lift the load precisely vertically, then the load can be expected to swing once it has been lifted clear of the pins. If the load is especially heavy, large, and/or fragile, it could hurt workers and/or damage itself and nearby objects. By indicating whether the load remains in contact with the pins when it has been lifted a fraction of the length of the pins, the crane-load contact sensor helps the crane operator determine whether it is safe to lift the load clear of the pins: If there is contact, then the load is resting against the sides of the pins and, hence, it may not be safe to lift; if contact is occasionally broken, then the load is probably not resting against the pins, so it should be safe to lift. It is assumed that the load and base, or at least the pins and the surfaces of the alignment holes in the load, are electrically conductive, so the instrument can use electrical contact to indicate mechanical contact. However, DC resistance cannot be used as an indicator of contact for the following reasons: The load and the base are both electrically grounded through cables (the load is grounded through the lifting cable of the crane) to prevent discharge of static electricity. In other words, the DC resistance between the load and the pins is always low, as though they were always in direct contact. Therefore, instead of DC resistance, the instrument utilizes the AC electrical impedance between the pins and the load. The signal frequency used in the measurement is high enough (.1 MHz) that the impedance contributed by the cables and the electrical ground network of the building in which the crane and the base are situated is significantly greater than the contact

  17. The New York Times ad.

    PubMed

    Hunt, M E; Kissling, F

    1993-01-01

    Feminization of patriarchal institutions is necessary in order to eliminate the exclusivity and mutuality of hierarchical, gender, class, and race stratification. The aim of this paper is to explain the history and activities surrounding the New York Times ad on Sunday, October 7, 1984 (the Catholic Statement on Pluralism and Abortion signed by Barbara Ferraro and Patricia Hussey of the Sisters of Note Dame de Namur, Rose Dominic Trapasso of the Maryknoll Sisters, and 67 other signers). The significance of this ad for Roman Catholic feminists and suggestions for new models of relationships between feminists is given. The Statement was written by Daniel Maguire and Frances Kissling and reviewed by 20 Roman Catholic ethicists. A sponsoring committee of early signers sought other support. Catholics for a Free Choice sponsored the funding for circulation of the Statement among professional societies, but not necessarily canonical communities. Publication of the entire statement in the Times was at the height of the presidential campaign. Conservative Bishops Bernard Law of Boston and John O'Connor of Boston publicly denounced Ferraro's position. The first institutional church response came on November 14, 1984, and stated that the Statement was personal opinion and contradictory to clear and constant church teachings about abortion. On November 30, 1984, Cardinal Jean Jerome Hamer of the Congregation for Religious and Secular Institutes responded to most presidents of canonical communities to request a public retraction from signers under threat of dismissal. The issue was obedience to the church. Several members of the canonical community and priests published retractions; negotiations with the Vatican began. Freedom of conscience and empowerment of canonical communities, as agents of their own lives, were given as reasons for the challenge to paternalism. The response was that women were subject to obedience within their communities and had taken public vows and were

  18. Ferromagnetic tunnel contacts to graphene: Contact resistance and spin signal

    SciTech Connect

    Cubukcu, M.; Laczkowski, P.; Vergnaud, C.; Marty, A.; Attané, J.-P.; Notin, L.; Vila, L. Jamet, M.; Martin, M.-B.; Seneor, P.; Anane, A.; Deranlot, C.; Fert, A.; Auffret, S.; Ducruet, C.

    2015-02-28

    We report spin transport in CVD graphene-based lateral spin valves using different magnetic contacts. We compared the spin signal amplitude measured on devices where the cobalt layer is directly in contact with the graphene to the one obtained using tunnel contacts. Although a sizeable spin signal (up to ∼2 Ω) is obtained with direct contacts, the signal is strongly enhanced (∼400 Ω) by inserting a tunnel barrier. In addition, we studied the resistance-area product (R.A) of a variety of contacts on CVD graphene. In particular, we compared the R.A products of alumina and magnesium oxide tunnel barriers grown by sputtering deposition of aluminum or magnesium and subsequent natural oxidation under pure oxygen atmosphere or by plasma. When using an alumina tunnel barrier on CVD graphene, the R.A product is high and exhibits a large dispersion. This dispersion can be highly reduced by using a magnesium oxide tunnel barrier, as for the R.A value. This study gives insight in the material quest for reproducible and efficient spin injection in CVD graphene.

  19. Intracellular Signaling and Desmoglein 2 Shedding Triggered by Human Adenoviruses Ad3, Ad14, and Ad14P1

    PubMed Central

    Wang, Hongjie; Ducournau, Corinne; Saydaminova, Kamola; Richter, Maximilian; Yumul, Roma; Ho, Martin; Carter, Darrick; Zubieta, Chloé

    2015-01-01

    ABSTRACT We recently discovered that desmoglein 2 (DSG2) is a receptor for human adenovirus species B serotypes Ad3, Ad7, Ad11, and Ad14. Ad3 is considered to be a widely distributed human pathogen. Ad3 binding to DSG2 triggers the transient opening of epithelial junctions. Here, we further delineate the mechanism that leads to DSG2-mediated epithelial junction opening in cells exposed to Ad3 and recombinant Ad3 fiber proteins. We identified an Ad3 fiber knob-dependent pathway that involves the phosphorylation of mitogen-activated protein (MAP) kinases triggering the activation of the matrix-metalloproteinase ADAM17. ADAM17, in turn, cleaves the extracellular domain of DSG2 that links epithelial cells together. The shed DSG2 domain can be detected in cell culture supernatant and also in serum of mice with established human xenograft tumors. We then extended our studies to Ad14 and Ad14P1. Ad14 is an important research and clinical object because of the recent appearance of a new, more pathogenic strain (Ad14P1). In a human epithelial cancer xenograft model, Ad14P1 showed more efficient viral spread and oncolysis than Ad14. Here, we tested the hypothesis that a mutation in the Ad14P1 fiber knob could account for the differences between the two strains. While our X-ray crystallography studies suggested an altered three-dimensional (3D) structure of the Ad14P1 fiber knob in the F-G loop region, this did not significantly change the fiber knob affinity to DSG2 or the intracellular signaling and DSG2 shedding in epithelial cancer cells. IMPORTANCE A number of widely distributed adenoviruses use the epithelial junction protein DSG2 as a receptor for infection and lateral spread. Interaction with DSG2 allows the virus not only to enter cells but also to open epithelial junctions which form a physical barrier to virus spread. Our study elucidates the mechanism beyond virus-triggered junction opening with a focus on adenovirus serotype 3. Ad3 binds to DSG2 with its fiber

  20. Condom ads promote illicit sex.

    PubMed

    Kippley, J F

    1994-01-01

    Written in 1987, this opinion was republished in the wake of US President Bill Clinton's AIDS prevention media campaign promoting condom use which began January 1994, targeted at young adults aged 18-25. The author staunchly opposes condom use even though he admits that people do not consider abstinence from sex to be a serious option for the prevention of HIV/STD infection. He believes that there is no moral use of sex with a condom and that condoms have always been a sign of immorality, be it prostitution, adultery, fornication, or marital contraception. Likewise, the author laments the success enjoyed by Planned Parenthood in achieving the social acceptance of marital contraception and sex outside of marriage. The complete social acceptance of homosexual activity, however, remains to be achieved. Magazines, newspapers, and television receive income in exchange for publishing or airing advertisements. Finding offensive advertisements which promote the use of condoms against HIV infection, the author recommends writing letters of complaint to the responsible media sources. If the television stations or publications in question continue to advertise condoms to the public, stop watching them or end one's subscriptions to the particular printed media. Such action taken collectively among many individuals will reduce product sales and income, and potentially sway corporate policy against condom ads.

  1. 16 CFR 460.18 - Insulation ads.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation and... your ad gives a price, you must give the type of insulation, the R-value at a specific thickness, the... you give the price per square foot, you do not have to give the coverage area. (c) If your ad...

  2. 16 CFR 460.18 - Insulation ads.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation and... your ad gives a price, you must give the type of insulation, the R-value at a specific thickness, the... you give the price per square foot, you do not have to give the coverage area. (c) If your ad...

  3. Myths & Facts about Value-Added Analysis

    ERIC Educational Resources Information Center

    TNTP, 2011

    2011-01-01

    This paper presents myths as well as facts about value-added analysis. These myths include: (1) "Value-added isn't fair to teachers who work in high-need schools, where students tend to lag far behind academically"; (2) "Value-added scores are too volatile from year-to-year to be trusted"; (3) "There's no research behind value-added"; (4) "Using…

  4. New Features in the ADS Abstract Service

    NASA Technical Reports Server (NTRS)

    Eichhorn, Guenther; Accomazzi, Alberto; Grant, Carolyn S.; Kurtz, Michael J.; Henneken, Edwin A.; Thompson, Donna M.; Murray, Stephen S.

    2005-01-01

    The NASA-ADS Abstract Service provides a sophisticated search capability for the literature in Astronomy, Planetary Sciences, Physics/Geophysics, and Space Instrumentation. The ADS is funded by NASA and access to the ADS services is free to anybody world-wide without restrictions. It allows the user to search the literature by author, title, and abstract text.

  5. 27 CFR 19.456 - Adding denaturants.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Adding denaturants. 19.456... Denaturation § 19.456 Adding denaturants. Denaturants and spirits shall be mixed in packages, tanks, or bulk... proprietor shall submit a flow diagram of the intended process or method of adding denaturants. (Sec....

  6. Weighing the Claims in Diet Ads

    MedlinePlus

    ... página en español Weighing the Claims in Diet Ads Related Items Weight Loss Challenge Diet Ads and ... control Information Network .  The Truth Behind Weight Loss Ads Claims to watch out for include: Lose weight ...

  7. On the structure of contact binaries. I - The contact discontinuity

    NASA Technical Reports Server (NTRS)

    Shu, F. H.; Lubow, S. H.; Anderson, L.

    1976-01-01

    The problem of the interior structure of contact binaries is reviewed, and a simple resolution of the difficulties which plague the theory is suggested. It is proposed that contact binaries contain a contact discontinuity between the lower surface of the common envelope and the Roche lobe of the cooler star. This discontinuity is maintained against thermal diffusion by fluid flow, and the transition layer is thin to the extent that the dynamical time scale is short in comparison with the thermal time scale. The idealization that the transition layer has infinitesimal thickness allows a simple formulation of the structure equations which are closed by appropriate jump conditions across the discontinuity. The further imposition of the standard boundary conditions suffices to define a unique model for the system once the chemical composition, the masses of the two stars, and the orbital separation are specified.

  8. SARS Patients and Their Close Contacts

    MedlinePlus

    ... Fact Sheet for SARS Patients and Their Close Contacts Format: Select one PDF [256 KB] Recommend on ... that are not now known. What does "close contact" mean? In the context of SARS, close contact ...

  9. 78 FR 30303 - National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-22

    ... ADMINISTRATION National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation Survey AGENCY: Contact Center Services, Federal Citizen Information Center, Office of Citizen Services... requirement regarding the National Contact Center customer evaluation surveys. In this request, the...

  10. 78 FR 14549 - National Contact Center; Information Collection; National Contact Center Customer Evaluation Survey

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-06

    ... ADMINISTRATION National Contact Center; Information Collection; National Contact Center Customer Evaluation Survey AGENCY: Contact Center Services, Federal Citizen Information Center, Office of Citizen Services... requirement regarding the National Contact Center customer evaluation surveys. In this request, the...

  11. Marine Bioinspired Underwater Contact Adhesion.

    PubMed

    Clancy, Sean K; Sodano, Antonio; Cunningham, Dylan J; Huang, Sharon S; Zalicki, Piotr J; Shin, Seunghan; Ahn, B Kollbe

    2016-05-09

    Marine mussels and barnacles are sessile biofouling organisms that adhere to a number of surfaces in wet environments and maintain remarkably strong bonds. Previous synthetic approaches to mimic biological wet adhesive properties have focused mainly on the catechol moiety, present in mussel foot proteins (mfps), and especially rich in the interfacial mfps, for example, mfp-3 and -5, found at the interface between the mussel plaque and substrate. Barnacles, however, do not use Dopa for their wet adhesion, but are instead rich in noncatecholic aromatic residues. Due to this anomaly, we were intrigued to study the initial contact adhesion properties of copolymerized acrylate films containing the key functionalities of barnacle cement proteins and interfacial mfps, for example, aromatic (catecholic or noncatecholic), cationic, anionic, and nonpolar residues. The initial wet contact adhesion of the copolymers was measured using a probe tack testing apparatus with a flat-punch contact geometry. The wet contact adhesion of an optimized, bioinspired copolymer film was ∼15.0 N/cm(2) in deionized water and ∼9.0 N/cm(2) in artificial seawater, up to 150 times greater than commercial pressure-sensitive adhesive (PSA) tapes (∼0.1 N/cm(2)). Furthermore, maximum wet contact adhesion was obtained at ∼pH 7, suggesting viability for biomedical applications.

  12. Contact tracing and disease control.

    PubMed Central

    Eames, Ken T D; Keeling, Matt J

    2003-01-01

    Contact tracing, followed by treatment or isolation, is a key control measure in the battle against infectious diseases. It is an extreme form of locally targeted control, and as such has the potential to be highly efficient when dealing with low numbers of cases. For this reason it is frequently used to combat sexually transmitted diseases and new invading pathogens. Accurate modelling of contact tracing requires explicit information about the disease-transmission pathways from each individual, and hence the network of contacts. Here, pairwise-approximation methods and full stochastic simulations are used to investigate the utility of contact tracing. A simple relationship is found between the efficiency of contact tracing necessary for eradication and the basic reproductive ratio of the disease. This holds for a wide variety of realistic situations including heterogeneous networks containing core-groups or super-spreaders, and asymptomatic individuals. Clustering (transitivity) within the transmission network is found to destroy the relationship, requiring lower efficiency than predicted. PMID:14728778

  13. Contact electrification of insulating materials

    NASA Astrophysics Data System (ADS)

    Lacks, Daniel J.; Mohan Sankaran, R.

    2011-11-01

    The electrostatic charge that is generated when two materials are contacted or rubbed and then separated is a well-known physical process that has been studied for more than 2500 years. Contact electrification occurs in many contexts, both natural and technological. For example, in dust storms the collisions between particles lead to electrostatic charging and in extreme cases, extraordinary lightning displays. In electrophotography, toner particles are intentionally charged to guide their deposition in well-defined patterns. Despite such a long history and so many important consequences, a fundamental understanding of the mechanism behind contact electrification remains elusive. An open question is what type of species are transferred between the surfaces to generate charge—experiments suggest various species ranging from electrons to ions to nanoscopic bits of material, and theoretical work suggests that non-equilibrium states may play an important role. Another open question is the contact electrification that occurs when two insulating materials with identical physical properties touch—since there is no apparent driving force, it is not clear why charge transfer occurs. A third open question involves granular systems—models and experiments have shown that a particle-size dependence for the charging often exists. In this review, we discuss the fundamental aspects of contact electrification and highlight recent research efforts aimed at understanding these open questions.

  14. Antibacterial surface design - Contact kill

    NASA Astrophysics Data System (ADS)

    Kaur, Rajbir; Liu, Song

    2016-08-01

    Designing antibacterial surfaces has become extremely important to minimize Healthcare Associated Infections which are a major cause of mortality worldwide. A previous biocide-releasing approach is based on leaching of encapsulated biocides such as silver and triclosan which exerts negative impacts on the environment and potentially contributes to the development of bacterial resistance. This drawback of leachable compounds led to the shift of interest towards a more sustainable and environmentally friendly approach: contact-killing surfaces. Biocides that can be bound onto surfaces to give the substrates contact-active antibacterial activity include quaternary ammonium compounds (QACs), quaternary phosphoniums (QPs), carbon nanotubes, antibacterial peptides, and N-chloramines. Among the above, QACs and N-chloramines are the most researched contact-active biocides. We review the engineering of contact-active surfaces using QACs or N-chloramines, the modes of actions as well as the test methods. The charge-density threshold of cationic surfaces for desired antibacterial efficacy and attempts to combine various biocides for the generation of new contact-active surfaces are discussed in detail. Surface positive charge density is identified as a key parameter to define antibacterial efficacy. We expect that this research field will continue to attract more research interest in view of the potential impact of self-disinfective surfaces on healthcare-associated infections, food safety and corrosion/fouling resistance required on industrial surfaces such as oil pipes and ship hulls.

  15. Dermatitis, contact on the cheek (image)

    MedlinePlus

    ... skin inflammation (dermatitis) on the cheek caused by contact with a substance that produced an allergic reaction (allergen). Contact dermatitis causes redness, itching, and small blisters (vesicles).

  16. Contacts de langues et representations (Language Contacts and Representations).

    ERIC Educational Resources Information Center

    Matthey, Marinette, Ed.

    1997-01-01

    Essays on language contact and the image of language, entirely in French, include: "Representations 'du' contexte et representations 'en' contexte? Eleves et enseignants face a l'apprentissage de la langue" ("Representations 'of' Context or Representations 'in' Context? Students and Teachers Facing Language Learning" (Laurent…

  17. Rolling Contact Force Energy Reconstruction

    NASA Astrophysics Data System (ADS)

    BRACCIALI, A.; CASCINI, G.

    2000-09-01

    Knowledge of the forces at the wheel-rail contact is fundamental to estimate the consequences in terms of noise and vibration. The traditional use of strain gauges mounted on the wheel web and axle is not capable of determining the high-frequency content of the contact force. Measurements made on the rail are characterized by the spatial variability of input-output transfer functions which makes it difficult to estimate the contact force by simple inversion of the point frequency response function. In this study the problem of rolling contact force reconstruction has been approached through the following steps: (i) the track has been characterized precisely for a finite length by the analysis of the time series of several impacts supplied with an instrumented hammer by using an ARMAX model that proved to be capable of modelling the vertical dynamics of the rail up to 5 kHz; (ii) the response of the rail has been simulated with a random force acting on the system, and the variability of the transfer function has been taken into account by distributing the force on adjacent elements; (iii) the simulated response has been compared with the rail acceleration measured for the passage of several trains; (iv) the wheel-rail contact force has been estimated with a closed-loop algorithm. It has thus been possible to reconstruct the13octave power spectrum of contact forces with a simple and stable iterative procedure. Forces reconstructed from different sensors were found to be practically the same for a given wheel; forces from nominally similar wheels are statistically examined and partial results of comparisons made on different rolling stock are shown.

  18. Methylisothiazolinone contact allergy: a review.

    PubMed

    Lundov, M D; Krongaard, T; Menné, T L; Johansen, J D

    2011-12-01

    In the early 2000s the preservative methylisothiazolinone (MI) was released as an individual preservative for industrial products and, in 2005, it was permitted for use in cosmetic products. Up until then MI had been used only in combination with methylchloroisothiazolinone (MCI). MCI/MI is one of the most frequent causes of preservative contact allergy and early studies showed that both MI and MCI are sensitizers. The prevalence of MI contact allergy is already around 1·5% and sources of exposure are associated with occupation, cosmetic products or household products. Use of MI in industrial products is not restricted and cases of occupational contact allergy to MI, e.g. in painters, are reported. The frequency of use of MI in cosmetics is low, around 1%, while up to 16·5% of household products were preserved with MI. We found 19 (1·5%) out of 1272 cosmetic products labelled with MI, primarily rinse-off products, and analysed the concentration of MI by high-performance-liquid-chromatography the ultraviolet and mass spectrometry detection. The use concentration ranged between 2 and 100 ppm. Repeated exposure to MI showed that many patients allergic to MI reacted to 50 ppm which is half the maximum permitted concentration of MI in cosmetics. The recent cases and prevalence studies on MI contact allergy could be the first sign of an epidemic of MI contact allergy. The development in prevalence of MI contact allergy should be closely monitored by including MI in the European Baseline Series at 2000 ppm.

  19. Point contact silicon solar cells

    NASA Technical Reports Server (NTRS)

    Swanson, R. M.

    1986-01-01

    The construction of a 22.2% efficient single-crystal silicon solar cell fabricated at Stanford University is described. The cell dimensions were 3 x 5 mm and 100 microns thick with a base lifetime of 500 microseconds. The cell featured light trapping between a texturized top surface and a reflective bottom surface, small point contact diffusions, alternating between n-type and p-type in a polka-dot pattern on the bottom surface, and a surface passivation on all surfaces between contact regions.

  20. Allergic contact dermatitis and cosmetics.

    PubMed

    Watkins, Shannon; Zippin, Jonathan

    2012-10-01

    Contact dermatitis is a common dermatologic condition that can result from exposure to allergens at home or at work. Cosmetics represent a large diverse group of products that Americans apply to their skin to treat disease or enhance beauty. With increased use of cosmetics, the rate of sensitization to many allergenic components has increased. We review the more common allergens present in cosmetics as well as the types of cosmetics that are known to contain them. With proper education and patch testing, dermatologists will be able to identify contact allergies to cosmetic ingredients and help patients avoid the offending products.

  1. Thermal and electrical contact conductance studies

    NASA Technical Reports Server (NTRS)

    Vansciver, S. W.; Nilles, M.

    1985-01-01

    Prediction of electrical and thermal contact resistance for pressed, nominally flat contacts is complicated by the large number of variables which influence contact formation. This is reflected in experimental results as a wide variation in contact resistances, spanning up to six orders of magnitude. A series of experiments were performed to observe the effects of oxidation and surface roughness on contact resistance. Electrical contact resistance and thermal contact conductance from 4 to 290 K on OFHC Cu contacts are reported. Electrical contact resistance was measured with a 4-wire DC technique. Thermal contact conductance was determined by steady-state longitudinal heat flow. Corrections for the bulk contribution ot the overall measured resistance were made, with the remaining resistance due solely to the presence of the contact.

  2. Contact urticaria, allergic contact dermatitis, and photoallergic contact dermatitis from oxybenzone.

    PubMed

    Landers, Maeran; Law, Sandra; Storrs, Frances J

    2003-03-01

    There is little literature regarding conventional patch tests and photopatch tests to oxybenzone resulting in both immediate- and delayed-type hypersensitivity reactions. A patient was patch-tested and photopatch-tested to various sunscreen chemicals. Both immediate- and delayed-type hypersensitivity reactions were observed with oxybenzone. The positive patch tests were also photoaccentuated. Oxybenzone, a common sunscreen allergen, can result in both contact urticaria and delayed-type hypersensitivity on both conventional patch testing and photopatch testing. Allergic contact dermatitis to sunscreen chemicals has traditionally included contact urticaria, allergic contact dermatitis, and photoallergic contact dermatitis. Due to the recognition of p-aminobenzoic acid (PABA) and its esters as sensitizers, the presence of benzophenones in "PABA-free" sunscreens has become more prevalent, especially in sunscreens with a sun protection factor (SPF) greater than 8. In our patient, immediate- and delayed-type hypersensitivity reactions were seen to oxybenzone (2-hydroxy-4-methoxybenzophenone, 2-benzoyl-5-methoxyphenol, benzophenone-3, Eusolex 4360, Escalol 567, EUSORB 228, Spectra-Sorb UV-9, Uvinul M-40) upon conventional patch testing and photopatch testing.

  3. Imaging surface contacts: Power law contact distributions and contact stresses in quartz, calcite, glass and acrylic plastic

    USGS Publications Warehouse

    Dieterich, J.H.; Kilgore, B.D.

    1996-01-01

    A procedure has been developed to obtain microscope images of regions of contact between roughened surfaces of transparent materials, while the surfaces are subjected to static loads or undergoing frictional slip. Static loading experiments with quartz, calcite, soda-lime glass and acrylic plastic at normal stresses to 30 MPa yield power law distributions of contact areas from the smallest contacts that can be resolved (3.5 ??m2) up to a limiting size that correlates with the grain size of the abrasive grit used to roughen the surfaces. In each material, increasing normal stress results in a roughly linear increase of the real area of contact. Mechanisms of contact area increase are by growth of existing contacts, coalescence of contacts and appearance of new contacts. Mean contacts stresses are consistent with the indentation strength of each material. Contact size distributions are insensitive to normal stress indicating that the increase of contact area is approximately self-similar. The contact images and contact distributions are modeled using simulations of surfaces with random fractal topographies. The contact process for model fractal surfaces is represented by the simple expedient of removing material at regions where surface irregularities overlap. Synthetic contact images created by this approach reproduce observed characteristics of the contacts and demonstrate that the exponent in the power law distributions depends on the scaling exponent used to generate the surface topography.

  4. Joule-Thomson expansion of the charged AdS black holes

    NASA Astrophysics Data System (ADS)

    Ökcü, Özgür; Aydıner, Ekrem

    2017-01-01

    In this paper, we study Joule-Thomson effects for charged AdS black holes. We obtain inversion temperatures and curves. We investigate similarities and differences between van der Waals fluids and charged AdS black holes for the expansion. We obtain isenthalpic curves for both systems in the T- P plane and determine the cooling-heating regions.

  5. Static Einstein-Maxwell Black Holes with No Spatial Isometries in AdS Space.

    PubMed

    Herdeiro, Carlos A R; Radu, Eugen

    2016-11-25

    We explicitly construct static black hole solutions to the fully nonlinear, D=4, Einstein-Maxwell-anti-de Sitter (AdS) equations that have no continuous spatial symmetries. These black holes have a smooth, topologically spherical horizon (section), but without isometries, and approach, asymptotically, global AdS spacetime. They are interpreted as bound states of a horizon with the Einstein-Maxwell-AdS solitons recently discovered, for appropriate boundary data. In sharp contrast to the uniqueness results for a Minkowski electrovacuum, the existence of these black holes shows that single, equilibrium, black hole solutions in an AdS electrovacuum admit an arbitrary multipole structure.

  6. Effects of ad placement and type on consumer responses to podcast ads.

    PubMed

    Ritter, Eric A; Cho, Chang-Hoan

    2009-10-01

    The purpose of this study was to understand the effects of podcast ad placement and podcast ad type on consumers' perceived intrusiveness, perceived irritation, attitude toward the ad, and ad avoidance. Our 2 x 2 (traditional ad vs. sponsorship by beginning vs. middle) experimental study found that sponsorships generated better consumer responses than did traditional ads and that podcast ads placed at the beginning of audio podcasts yielded better consumer responses than those placed in the middle. Implications for marketers and advertisers are discussed.

  7. Boundary conditions for conformally coupled scalar in AdS4

    NASA Astrophysics Data System (ADS)

    Oh, Jae-Hyuk

    2015-06-01

    We consider conformally coupled scalar with ɸ4 coupling in AdS4 and study its various boundary conditions on AdS boundary. We have obtained perturbative solutions of equation of motion of the conformally coupled scalar with power expansion order by order in ɸ4 coupling λ up to λ2 order. In its dual CFT, we get 2, 4 and 6 point functions by using this solution with Dirichlet and Neumann boundary conditions via AdS/CFT dictionary. We also consider marginal deformation on AdS boundary and get its on-shell and boundary effective actions.

  8. Allergic contact dermatitis to cosmetics.

    PubMed

    Park, Michelle E; Zippin, Jonathan H

    2014-01-01

    Allergic contact dermatitis caused by cosmetic products is an increasing concern given the continual creation and introduction of new cosmetics to the public. This article presents an overview of how to evaluate a patient for patch testing, including common areas for cosmetic-induced dermatitis, common cosmetic allergens, and proper management.

  9. Non-contact ECG monitoring

    NASA Astrophysics Data System (ADS)

    Smirnov, Alexey S.; Erlikh, Vadim V.; Kodkin, Vladimir L.; Keller, Andrei V.; Epishev, Vitaly V.

    2016-03-01

    The research is dedicated to non-contact methods of electrocardiography. The authors describe the routine of experimental procedure and suggest the approach to solving the problems which arise at indirect signal recording. The paper presents the results of experiments conducted by the authors, covers the flow charts of ECG recorders and reviews the drawbacks of filtering methods used in foreign equivalents.

  10. Barrier/Cu contact resistivity

    SciTech Connect

    Reid, J.S.; Nicolet, M.A.; Angyal, M.S.; Lilienfeld, D.; Shacham-Diamand, Y.; Smith, P.M.

    1995-10-17

    The specific contact resistivity of Cu with ({alpha} + {beta})-Ta, TiN, {alpha}-W, and amorphous-Ta{sub 36}Si{sub 14}N{sub 50} barrier films is measured using a novel four-point-probe approach. Geometrically, the test structures consist of colinear sets of W-plugs to act as current and voltage probes that contact the bottom of a planar Cu/barrier/Cu stack. Underlying Al interconnects link the plugs to the current source and voltmeter. The center-to-center distance of the probes ranges from 3 to 200 {micro}m. Using a relation developed by Vu et al., a contact resistivity of roughly 7 {times} 10{sup {minus}9} {Omega} cm{sup 2} is obtained for all tested barrier/Cu combinations. By reflective-mode small-angle X-ray scattering, the similarity in contact resistivity among the barrier films may be related to interfacial impurities absorbed from the deposition process.

  11. Ohmic contacts to semiconducting diamond

    NASA Astrophysics Data System (ADS)

    Zeidler, James R.; Taylor, M. J.; Zeisse, Carl R.; Hewett, C. A.; Delahoussaye, Paul R.

    1990-10-01

    Work was carried out to improve the electron beam evaporation system in order to achieve better deposited films. The basic system is an ion pumped vacuum chamber, with a three-hearth, single-gun e-beam evaporator. Four improvements were made to the system. The system was thoroughly cleaned and new ion pump elements, an e-gun beam adjust unit, and a more accurate crystal monitor were installed. The system now has a base pressure of 3 X 10(exp -9) Torr, and can easily deposit high-melting-temperature metals such as Ta with an accurately controlled thickness. Improved shadow masks were also fabricated for better alignment and control of corner contacts for electrical transport measurements. Appendices include: A Thermally Activated Solid State Reaction Process for Fabricating Ohmic Contacts to Semiconducting Diamond; Tantalum Ohmic Contacts to Diamond by a Solid State Reaction Process; Metallization of Semiconducting Diamond: Mo, Mo/Au, and Mo/Ni/Au; Specific Contact Resistance Measurements of Ohmic Contracts to Diamond; and Electrical Activation of Boron Implanted into Diamond.

  12. Contact symmetries and Hamiltonian thermodynamics

    SciTech Connect

    Bravetti, A.; Lopez-Monsalvo, C.S.; Nettel, F.

    2015-10-15

    It has been shown that contact geometry is the proper framework underlying classical thermodynamics and that thermodynamic fluctuations are captured by an additional metric structure related to Fisher’s Information Matrix. In this work we analyse several unaddressed aspects about the application of contact and metric geometry to thermodynamics. We consider here the Thermodynamic Phase Space and start by investigating the role of gauge transformations and Legendre symmetries for metric contact manifolds and their significance in thermodynamics. Then we present a novel mathematical characterization of first order phase transitions as equilibrium processes on the Thermodynamic Phase Space for which the Legendre symmetry is broken. Moreover, we use contact Hamiltonian dynamics to represent thermodynamic processes in a way that resembles the classical Hamiltonian formulation of conservative mechanics and we show that the relevant Hamiltonian coincides with the irreversible entropy production along thermodynamic processes. Therefore, we use such property to give a geometric definition of thermodynamically admissible fluctuations according to the Second Law of thermodynamics. Finally, we show that the length of a curve describing a thermodynamic process measures its entropy production.

  13. Electrical contact tool set station

    DOEpatents

    Byers, M.E.

    1988-02-22

    An apparatus is provided for the precise setting to zero of electrically conductive cutting tools used in the machining of work pieces. An electrically conductive cylindrical pin, tapered at one end to a small flat, rests in a vee-shaped channel in a base so that its longitudinal axis is parallel to the longitudinal axis of the machine's spindle. Electronic apparatus is connected between the cylindrical pin and the electrically conductive cutting tool to produce a detectable signal when contact between tool and pin is made. The axes of the machine are set to zero by contact between the cutting tool and the sides, end or top of the cylindrical pin. Upon contact, an electrical circuit is completed, and the detectable signal is produced. The tool can then be set to zero for that axis. Should the tool contact the cylindrical pin with too much force, the cylindrical pin would be harmlessly dislodged from the vee-shaped channel, preventing damage either to the cutting tool or the cylindrical pin. 5 figs.

  14. Interfacial closure of contacting surfaces

    NASA Astrophysics Data System (ADS)

    Rieutord, F.; Rauer, C.; Moriceau, H.

    2014-08-01

    Understanding the contact between solid surfaces is a long-standing problem which has a strong impact on the physics of many processes such as adhesion, friction, lubrication and wear. Experimentally, the investigation of solid/solid interfaces remains challenging today, due to the lack of experimental techniques able to provide sub-nanometer scale information on interfaces buried between millimeters of materials. Yet, a strong interest exists improving the modeling of contact mechanics of materials in order to adjust their interface properties (e.g., thermal transport, friction). We show here that the essential features of the residual gap between contacting surfaces can be measured using high energy X-ray synchrotron reflectivity. The presence of this nano-gap is general to the contact of solids. In some special case however, it can be removed when attractive forces take over repulsive contributions, depending on both height and wavelength of asperity distributions (roughness). A criterion for this instability is established in the standard case of van der Waals attractive forces and elastic asperity compression repulsive forces (Hertz model). This collapse instability is confirmed experimentally in the case of silicon direct bonding, using high-energy X-ray synchrotron reflectivity and adhesion energy measurements. The possibility to achieve fully closed interfaces at room temperature opens interesting perspectives to build stronger assemblies with smaller thermal budgets.

  15. [Allergic contact eczema to ninhydrin].

    PubMed

    Schlacke, K H; Fuchs, T

    1989-01-01

    Use of a surgical marking pen to indicate test areas on the skin during epicutaneous evaluation caused eczema in three female patients undergoing patch testing. Close scrutiny of the individual components of this surgical marking pen revealed contact dermatitis to ninhydrine, a substance whose allergenic potential has hardly been noted in the relevant literature.

  16. A more reliable measurement method for metal/graphene contact resistance.

    PubMed

    Wang, Shaoqing; Mao, Dacheng; Jin, Zhi; Peng, Songang; Zhang, Dayong; Shi, Jingyuan; Wang, Xuanyun

    2015-10-09

    The contact resistance of metal/graphene is becoming a major limiting factor for graphene devices. Among various kinds of contact resistance test methods, the transmission line model is the most common approach to extract contact resistance in graphene devices. However, experiments show that in some cases there exists large inaccuracy and instability using this method. In this study, we added a cross-bridge structure at the terminal of the transmission line as a supporting test. This modified transmission line measurement structure can easily compare not only the transmission line and Kelvin contact resistance, getting a more reliable value, but also the other contact-related parameters, such as specific contact resistivity, transfer length and the graphene sheet resistance under and outside contact metal at the same time. The new measurement test is very helpful in enabling us to study the contact property accurately. The specific contact resistivity in our experiment is in the range of 2.0 × 10(-6) Ω · cm(2) and 3.0 × 10(-6) Ω · cm(2) at room temperature. With the temperature decreasing from 290 K to 60 K, the transfer length fluctuates around 1.7 μm, and the specific contact resistivity reduces to less than 2.0 × 10(-6) Ω · cm(2).

  17. Inseparability of photon-added Gaussian states

    SciTech Connect

    Li Hongrong; Li Fuli; Zhu Shiyao

    2007-06-15

    The inseparability of photon-added Gaussian states which are generated from two-mode Gaussian states by adding photons is investigated. According to the established inseparability conditions [New J. Phys. 7, 211 (2005); Phys. Rev. Lett. 96, 050503 (2006)], we find that even if a two-mode Gaussian state is separable, the photon-added Gaussian state becomes entangled when the purity of the Gaussian state is larger than a certain value. The lower bound of entanglement of symmetric photon-added Gaussian states is derived. The result shows that entanglement of the photon-added Gaussian states is involved with high-order moment correlations. We find that fidelity of teleporting coherent states cannot be raised by employing the photon-added Gaussian states as a quantum channel of teleportation.

  18. Computing Contact Stresses In Gear Teeth

    NASA Technical Reports Server (NTRS)

    Oswald, Fred B.; Somprakit, Paisan; Huston, Ronald L.

    1995-01-01

    Improved method of computing contact stresses in gear teeth accounts for complicating effects like those of static and sliding friction. Provides iterative procedure for determination of contact region and nodal contact forces along with contact stresses. Method based on equations and computational procedure incorporating these effects routinely.

  19. Rutin suppresses atopic dermatitis and allergic contact dermatitis.

    PubMed

    Choi, Jin Kyeong; Kim, Sang-Hyun

    2013-04-01

    Atopic dermatitis (AD) and allergic contact dermatitis (ACD) is a common allergic inflammatory skin disease caused by a combination of eczematous, scratching, pruritus and cutaneous sensitization with allergens. The aim of our study was to examine whether rutin, a predominant flavonoid having anti-inflammatory and antioxidative potential, modulates AD and ACD symptoms. We established an atopic dermatitis model in BALB/c mice by repeated local exposure of house dust mite (Dermatophagoides farinae) extract (DFE) and 2,4-dinitrochlorobenzene (DNCB) to the ears. In addition, 2,4-dinitroflourobenzene-sensitized a local lymph node assay was used for the ACD model. Repeated alternative treatment of DFE/DNCB caused AD symptoms. Topical application of rutin reduced AD based on ear thickness and histopathological analysis, in addition to serum IgE levels. Rutin inhibited mast cell infiltration into the ear and serum histamine level. Rutin suppressed DFE/DNCB-induced expression of interleukin (IL)-4, IL-5, IL-13, IL-31, IL-32 and interferon (INF)-γ in the tissue. In addition, rutin suppressed ACD based on ear thickness and lymphocyte proliferation, serum IgG2a levels, and expression of INF-γ, IL-4, IL-5, IL-10, IL-17 and tumour necrosis factor-α in ACD ears. This study demonstrates that rutin inhibits AD and ACD, suggesting that rutin might be a candidate for the treatment of allergic skin diseases.

  20. PSD-95 promotes the stabilization of young synaptic contacts.

    PubMed

    Taft, Christine E; Turrigiano, Gina G

    2014-01-05

    Maintaining a population of stable synaptic connections is probably of critical importance for the preservation of memories and functional circuitry, but the molecular dynamics that underlie synapse stabilization is poorly understood. Here, we use simultaneous time-lapse imaging of post synaptic density-95 (PSD-95) and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) to investigate the dynamics of protein composition at axodendritic (AD) contacts. Our data reveal that this composition is highly dynamic, with both proteins moving into and out of the same synapse independently, so that synapses cycle rapidly between states in which they are enriched for none, one or both proteins. We assessed how PSD-95 and CaMKII interact at stable and transient AD sites and found that both phospho-CaMKII and PSD-95 are present more often at stable than labile contacts. Finally, we found that synaptic contacts are more stable in older neurons, and this process can be mimicked in younger neurons by overexpression of PSD-95. Taken together, these data show that synaptic protein composition is highly variable over a time-scale of hours, and that PSD-95 is probably a key synaptic protein that promotes synapse stability.

  1. Ground Contact Modeling for the Morpheus Test Vehicle Simulation

    NASA Technical Reports Server (NTRS)

    Cordova, Luis

    2013-01-01

    The Morpheus vertical test vehicle is an autonomous robotic lander being developed at Johnson Space Center (JSC) to test hazard detection technology. Because the initial ground contact simulation model was not very realistic, it was decided to improve the model without making it too computationally expensive. The first development cycle added capability to define vehicle attachment points (AP) and to keep track of their states in the lander reference frame (LFRAME). These states are used with a spring damper model to compute an AP contact force. The lateral force is then overwritten, if necessary, by the Coulomb static or kinetic friction force. The second development cycle added capability to use the PolySurface class as the contact surface. The class can load CAD data in STL (Stereo Lithography) format, and use the data to compute line of sight (LOS) intercepts. A polygon frame (PFRAME) is computed from the facet intercept normal and used to convert the AP state to PFRAME. Three flat plane tests validate the transitions from kinetic to static, static to kinetic, and vertical impact. The hazardous terrain test will be used to test for visual reasonableness. The improved model is numerically inexpensive, robust, and produces results that are reasonable.

  2. Ground Contact Modeling for the Morpheus Test Vehicle Simulation

    NASA Technical Reports Server (NTRS)

    Cordova, Luis

    2014-01-01

    The Morpheus vertical test vehicle is an autonomous robotic lander being developed at Johnson Space Center (JSC) to test hazard detection technology. Because the initial ground contact simulation model was not very realistic, it was decided to improve the model without making it too computationally expensive. The first development cycle added capability to define vehicle attachment points (AP) and to keep track of their states in the lander reference frame (LFRAME). These states are used with a spring damper model to compute an AP contact force. The lateral force is then overwritten, if necessary, by the Coulomb static or kinetic friction force. The second development cycle added capability to use the PolySurface class as the contact surface. The class can load CAD data in STL (Stereo Lithography) format, and use the data to compute line of sight (LOS) intercepts. A polygon frame (PFRAME) is computed from the facet intercept normal and used to convert the AP state to PFRAME. Three flat plane tests validate the transitions from kinetic to static, static to kinetic, and vertical impact. The hazardous terrain test will be used to test for visual reasonableness. The improved model is numerically inexpensive, robust, and produces results that are reasonable.

  3. Beyond contact: intergroup contact in the context of power relations.

    PubMed

    Saguy, Tamar; Dovidio, John F; Pratto, Felicia

    2008-03-01

    This work investigated how group-based power affects the motivations and preferences that members of advantaged and disadvantaged groups bring to situations of contact. To measure the preferred content of interactions, desires to address particular topics in intergroup contact were assessed for both experimental groups (Study 1) and real groups (Study 2). As predicted, across both studies, the desire to talk about power was greater among members of disadvantaged than of advantaged groups. This difference was mediated by motivation for change in group-based power. Study 2 further demonstrated that more highly identified members of disadvantaged groups wanted to talk about power more. Members of advantaged groups generally preferred to talk about commonalities between the groups more than about group-based power, and this desire was greater with higher levels of identification. However, perceiving that their group's advantage was illegitimate increased the desire of advantaged group members to address power in intergroup interactions.

  4. Improved Electrical Contact For Dowhhole Drilling Networks

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Fox, Joe; Sneddon, Cameron

    2005-08-16

    An electrical contact system for transmitting information across tool joints while minimizing signal reflections that occur at the tool joints includes a first electrical contact comprising an annular resilient material. An annular conductor is embedded within the annular resilient material and has a surface exposed from the annular resilient material. A second electrical contact is provided that is substantially equal to the first electrical contact. Likewise, the second electrical contact has an annular resilient material and an annular conductor. The two electrical contacts configured to contact one another such that the annular conductors of each come into physical contact. The annular resilient materials of each electrical contact each have dielectric characteristics and dimensions that are adjusted to provide desired impedance to the electrical contacts.

  5. Chain Of Test Contacts For Integrated Circuits

    NASA Technical Reports Server (NTRS)

    Lieneweg, Udo

    1989-01-01

    Test structure forms chain of "cross" contacts fabricated together with large-scale integrated circuits. If necessary, number of such chains incorporated at suitable locations in integrated-circuit wafer for determination of fabrication yield of contacts. In new structure, resistances of individual contacts determined: In addition to making it possible to identify local defects, enables generation of statistical distributions of contact resistances for prediction of "parametric" contact yield of fabrication process.

  6. From path integrals to tensor networks for the AdS /CFT correspondence

    NASA Astrophysics Data System (ADS)

    Miyaji, Masamichi; Takayanagi, Tadashi; Watanabe, Kento

    2017-03-01

    In this paper, we discuss tensor network descriptions of AdS /CFT from two different viewpoints. First, we start with a Euclidean path-integral computation of ground state wave functions with a UV cutoff. We consider its efficient optimization by making its UV cutoff position dependent and define a quantum state at each length scale. We conjecture that this path integral corresponds to a time slice of anti-de Sitter (AdS) spacetime. Next, we derive a flow of quantum states by rewriting the action of Killing vectors of AdS3 in terms of the dual two-dimensional conformal field theory (CFT). Both approaches support a correspondence between the hyperbolic time slice H2 in AdS3 and a version of continuous multiscale entanglement renormalization ansatz. We also give a heuristic argument about why we can expect a sub-AdS scale bulk locality for holographic CFTs.

  7. PREFACE: Non-contact AFM Non-contact AFM

    NASA Astrophysics Data System (ADS)

    Giessibl, Franz J.; Morita, Seizo

    2012-02-01

    This special issue is focussed on high resolution non-contact atomic force microscopy (AFM). Non-contact atomic force microscopy was established approximately 15 years ago as a tool to image conducting and insulating surfaces with atomic resolution. Since 1998, an annual international conference has taken place, and although the proceedings of these conferences are a useful source of information, several key developments warrant devoting a special issue to this subject. In the theoretic field, the possibility of supplementing established techniques such as scanning tunneling microscopy (STM) and Kelvin probe microscopy with atomically resolved force micrsoscopy poses many challenges in the calculation of contrast and contrast reversal. The surface science of insulators, self-assembled monolayers and adsorbates on insulators is a fruitful field for the application of non-contact AFM: several articles in this issue are devoted to these subjects. Atomic imaging and manipulation have been pioneered using STM, but because AFM allows the measurement of forces, AFM has had a profound impact in this field as well. Three-dimensional force spectroscopy has allowed many important insights into surface science. In this issue a combined 3D tunneling and force microscopy is introduced. Non-contact AFM typically uses frequency modulation to measure force gradients and was initially used mainly in a vacuum. As can be seen in this issue, frequency modulation is now also used in ambient conditions, allowing better spatial and force resolution. We thank all of the contributors for their time and efforts in making this special issue possible. We are also very grateful to the staff of IOP Publishing for handling the administrative aspects and for steering the refereeing process. Non-contact AFM contents Relation between the chemical force and the tunnelling current in atomic point contacts: a simple model Pavel Jelínek, Martin Ondrácek and Fernando Flores Theoretical simulation of

  8. = 4 supersymmetric Yang-Mills theories in AdS3

    NASA Astrophysics Data System (ADS)

    Kuzenko, Sergei M.; Tartaglino-Mazzucchelli, Gabriele

    2014-05-01

    For all types of = 4 anti-de Sitter (AdS) supersymmetry in three dimensions, we construct manifestly supersymmetric actions for Abelian vector multiplets and explain how to extend the construction to the non-Abelian case. Manifestly = 4 supersymmetric Yang-Mills (SYM) actions are explicitly given in the cases of (2,2) and critical (4,0) AdS supersymmetries. The = 4 vector multiplets and the corresponding actions are then reduced to (2,0) AdS superspace, in which only = 2 supersymmetry is manifest. Using the off-shell structure of the = 4 vector multiplets, we provide complete = 4 SYM actions in (2,0) AdS superspace for all types of = 4 AdS supersymmetry. In the case of (4,0) AdS supersymmetry, which admits a Euclidean counterpart, the resulting = 2 action contains a Chern-Simons term proportional to q/r, where r is the radius of AdS 3 and q is the R-charge of a chiral scalar superfield. The R-charge is a linear inhomogeneous function of X, an expectation value of the = 4 Cotton superfield. Thus our results explain the mysterious structure of = 4 supersymmetric Yang-Mills theories on S 3 discovered in arXiv:1401.7952. In the case of (3,1) AdS supersymmetry, which has no Euclidean counterpart, the SYM action contains both a Chern-Simons term and a chiral mass-like term. In the case of (2,2) AdS supersymmetry, which admits a Euclidean counterpart, the SYM action has no Chern-Simons and chiral mass-like terms.

  9. Sensing with Superconducting Point Contacts

    PubMed Central

    Nurbawono, Argo; Zhang, Chun

    2012-01-01

    Superconducting point contacts have been used for measuring magnetic polarizations, identifying magnetic impurities, electronic structures, and even the vibrational modes of small molecules. Due to intrinsically small energy scale in the subgap structures of the supercurrent determined by the size of the superconducting energy gap, superconductors provide ultrahigh sensitivities for high resolution spectroscopies. The so-called Andreev reflection process between normal metal and superconductor carries complex and rich information which can be utilized as powerful sensor when fully exploited. In this review, we would discuss recent experimental and theoretical developments in the supercurrent transport through superconducting point contacts and their relevance to sensing applications, and we would highlight their current issues and potentials. A true utilization of the method based on Andreev reflection analysis opens up possibilities for a new class of ultrasensitive sensors. PMID:22778630

  10. Remedial Action Contacts Directory - 1997

    SciTech Connect

    1997-05-01

    This document, which was prepared for the US Department of Energy (DOE) Office of Environmental Restoration (ER), is a directory of 2628 individuals interested or involved in environmental restoration and/or remedial actions at radioactively contaminated sites. This directory contains a list of mailing addresses and phone numbers of DOE operations, area, site, project, and contractor offices; an index of DOE operations, area, site, project, and contractor office sorted by state; a list of individuals, presented by last name, facsimile number, and e-mail address; an index of affiliations presented alphabetically, with individual contacts appearing below each affiliation name; and an index of foreign contacta sorted by country and affiliation. This document was generated from the Remedial Action Contacts Database, which is maintained by the Remedial Action Program Information Center (RAPIC).

  11. Sensing with superconducting point contacts.

    PubMed

    Nurbawono, Argo; Zhang, Chun

    2012-01-01

    Superconducting point contacts have been used for measuring magnetic polarizations, identifying magnetic impurities, electronic structures, and even the vibrational modes of small molecules. Due to intrinsically small energy scale in the subgap structures of the supercurrent determined by the size of the superconducting energy gap, superconductors provide ultrahigh sensitivities for high resolution spectroscopies. The so-called Andreev reflection process between normal metal and superconductor carries complex and rich information which can be utilized as powerful sensor when fully exploited. In this review, we would discuss recent experimental and theoretical developments in the supercurrent transport through superconducting point contacts and their relevance to sensing applications, and we would highlight their current issues and potentials. A true utilization of the method based on Andreev reflection analysis opens up possibilities for a new class of ultrasensitive sensors.

  12. Contact charge-transfer lasers

    SciTech Connect

    Dharamsi, A.N.; Tulip, J.

    1981-07-01

    A mechanism for sustaining population inversions in contact charge-transfer complexes in which the ground electronic state is not bound is described. The mechanism relies on picosecond radiationless depletion of the lower laser state. This generates an inversion even when the ground-state potential curve, as plotted against the donor-acceptor distance, is not repulsive vertically below the excited state minimum. Contact charge-transfer lasers would offer high gain, high-energy density, and tunable sources of coherent radiation in the uv and visible. A method for pumping such a laser is examined and applied to the pyrrole-oxygen complex. A rate equation analysis is done and estimates for gain and energy density are presented.

  13. Contact microscopy with synchrotron radiation

    SciTech Connect

    Panessa-Warren, B.J.

    1985-10-01

    Soft x-ray contact microscopy with synchrotron radiation offers the biologist and especially the microscopist, a way to morphologically study specimens that could not be imaged by conventional TEM, STEM or SEM methods (i.e. hydrated samples, samples easily damaged by an electron beam, electron dense samples, thick specimens, unstained low contrast specimens) at spatial resolutions approaching those of the TEM, with the additional possibility to obtain compositional (elemental) information about the sample as well. Although flash x-ray sources offer faster exposure times, synchrotron radiation provides a highly collimated, intense radiation that can be tuned to select specific discrete ranges of x-ray wavelengths or specific individual wavelengths which optimize imaging or microanalysis of a specific sample. This paper presents an overview of the applications of x-ray contact microscopy to biological research and some current research results using monochromatic synchrotron radiation to image biological samples. 24 refs., 10 figs.

  14. Contact lenses for infant aphakia.

    PubMed Central

    Amaya, L G; Speedwell, L; Taylor, D

    1990-01-01

    We prospectively studied for three years the optical correction by contact lenses of 83 aphakic infants (141 eyes) who generally also had systemic and other ocular anomalies: 85% of the patients tolerated the lens wear for the whole study period. Complications occurred in 46 eyes and led to cessation of lens wear in two cases. Ten patients abandoned the lenses for other reasons. Thirty-four eyes needed subsequent intraocular surgery, mostly minor, and nine patients had strabismus surgery. Contact lenses are a versatile, safe, successful, and cost effective treatment for aphakia in infancy against which, before their widespread introduction for primary optical correction of infant aphakia, other methods of aphakic treatment need to be compared. PMID:2322512

  15. Heat transport through atomic contacts.

    PubMed

    Mosso, Nico; Drechsler, Ute; Menges, Fabian; Nirmalraj, Peter; Karg, Siegfried; Riel, Heike; Gotsmann, Bernd

    2017-02-06

    Heat transport and dissipation at the nanoscale severely limit the scaling of high-performance electronic devices and circuits. Metallic atomic junctions serve as model systems to probe electrical and thermal transport down to the atomic level as well as quantum effects that occur in one-dimensional (1D) systems. Whereas charge transport in atomic junctions has been studied intensively in the past two decades, heat transport remains poorly characterized because it requires the combination of a high sensitivity to small heat fluxes and the formation of stable atomic contacts. Here we report heat-transfer measurements through atomic junctions and analyse the thermal conductance of single-atom gold contacts at room temperature. Simultaneous measurements of charge and heat transport reveal the proportionality of electrical and thermal conductance, quantized with the respective conductance quanta. This constitutes a verification of the Wiedemann-Franz law at the atomic scale.

  16. Protein contact dermatitis - Case report*

    PubMed Central

    Barata, Ana Rita Rodrigues; Conde-Salazar, Luis

    2013-01-01

    Protein contact dermatitis is a skin condition not well known and underdiagnosed by dermatologists, resulting from an IgE-mediated allergic reaction. Clinically it presents as a chronic hand and/or forearms eczema of occupational origin, especially in professionals who work as food handlers. Epicutaneous tests are negative, and to diagnose this condition it is necessary to perform immediate-type allergy tests. The most sensitive and practical is the prick-by-prick test with food that the patient refers to cause intense itching after immediate skin contact. Treatment is symptomatic, and it is mandatory to avoid the responsible allergen, wearing plastic gloves and even sometimes leaving the workplace for symptom resolution. PMID:24068135

  17. Alternatives to the ISS Plasma Contacting Units

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.

    2002-01-01

    A spacecraft in a high-density equatorial LEO plasma will float negative relative to the ambient plasma. Because of the electron collection of exposed conductors on its solar arrays, it may float negative by up to its array voltage. The floating potential depends on the relative areas of electron and ion collection of the spacecraft. Early estimates of the International Space Station (ISS) potential were about -140 V relative to the surrounding plasma, because of its 160 V solar array string voltage. Because of the possibility of arcing of ISS structures and astronaut EMUs (spacesuits) into the space plasma, Plasma Contacting Units (PCUs) were added to the ISS design, to reduce the highly negative floating potentials by emitting electrons (effectively increasing the ion collecting area). In addition to the now-operating ISS PCUs, safety rules require another independent arc-hazard control method. In this paper, I discuss alternatives to the ISS PCUs for keeping the ISS floating potential at values below the arc-thresholds of ISS and EMU surface materials. Advantages and disadvantages of all of the recline loss will be presented.

  18. Intermittent contact hydration scanning probe microscopy.

    PubMed

    Aloisi, G; Bacci, F; Carlà, M; Dolci, D

    2010-07-01

    Hydration scanning probe microscopy is a technique similar to scanning tunneling microscopy, in which the probe current, sustained by the slight surface conduction of a thin hydration layer covering an insulating support surface, is essentially electrochemical in nature instead of electronic tunneling. Such a technique allows the imaging of a great variety of samples, including insulators, provided that they are hydrophilic, as well as the study of molecular samples of biological interest (such as DNA) fixed on a suitable supporting surface. The main problem to obtain stable and reproducible images comes from the very critical determination of the operating conditions under which the probe-hydration layer interaction does not lead to the formation of a relatively large water meniscus. It has been suggested that this issue can be removed by adding a high frequency oscillation to the probe movement, as in tapping atomic force microscopy. Meniscus formation and breakup have been investigated in order to determine the best values for the amplitude and the frequency of the oscillation. Results obtained in this mode are discussed in comparison with the usual continuous contact mode.

  19. Beyond Test Scores: Adding Value to Assessment

    ERIC Educational Resources Information Center

    Rothman, Robert

    2010-01-01

    At a time when teacher quality has emerged as a key factor in student learning, a statistical technique that determines the "value added" that teachers bring to student achievement is getting new scrutiny. Value-added measures compare students' growth in achievement to their expected growth, based on prior achievement and demographic…

  20. Elbow Dislocations in Contact Sports.

    PubMed

    Morris, Mark S; Ozer, Kagan

    2017-02-01

    Elbow dislocations are more common in athletes than in the general population. Simple elbow dislocations should be managed with early range of motion and early return to sport, even with high-level contact athletes. Patients with instability on examination or with complex elbow dislocations may require surgical intervention. Overall, the outcomes after simple elbow dislocations are excellent and athletes should be able to return to play without significant limitations.

  1. Forces between membranes approaching contact.

    PubMed

    Parsegian, V A

    1981-01-01

    Cell stickiness to surfaces is recognized as an important concern in tests of red cell filterability. Many forces need to be considered in order to think about the sources of cell sticking. As cell membranes are brought together they experience successively the domination of several classes of forces van der Waals attraction, electrostatic repulsion, hydration repulsion, and specific charge-charge interactions at contact. The behaviour of each of these forces is described in the context of red cell adhesion.

  2. Allergic contact dermatitis to Alstroemeria.

    PubMed

    Marks, J G

    1988-06-01

    Two female florists developed dermatitis of the fingertips. Patch testing revealed allergic contact dermatitis to the flower, Alstroemeria, used in floral arrangements. They had positive patch tests to portions of Alstroemeria, and to tuliposide A, the allergen in this plant. Vinyl gloves were not helpful since tuliposide A readily penetrates through these gloves. Nitrile gloves may be protective since they prevented positive patch test to tuliposide A.

  3. Contact | Office of Cancer Genomics

    Cancer.gov

    For more information about the Office of Cancer Genomics, please contact: Office of Cancer Genomics National Cancer Institute 31 Center Drive, 10A07 Bethesda, Maryland 20892-2580 Phone: (301) 451-8027 Fax: (301) 480-4368 Email: ocg@mail.nih.gov *Please note that this site will not function properly in Internet Explorer unless you completely turn off the Compatibility View*

  4. Contact allergy to cocamidopropyl betaine.

    PubMed

    de Groot, A C; van der Walle, H B; Weyland, J W

    1995-12-01

    Cocamidopropyl betaine is an amphoteric surfactant used increasingly in cosmetic products. We describe 20 cases of cosmetic allergy to cocamidopropyl betaine; all were caused by shampoo or shower gel. 8 patients were hairdressers, who had occupational allergic contact dermatitis from shampoos. We recommend patch testing cocamidopropyl betaine 1% aq. routinely in hairdressers with dermatitis of the hands, and in all patients suspected of suffering from cosmetic allergy.

  5. Thermodynamic geometry and phase transitions of AdS braneworld black holes

    NASA Astrophysics Data System (ADS)

    Chaturvedi, Pankaj; Sengupta, Gautam

    2017-02-01

    The thermodynamics and phase transitions of charged RN-AdS and rotating Kerr-AdS black holes in a generalized Randall-Sundrum braneworld are investigated in the framework of thermodynamic geometry. A detailed analysis of the thermodynamics, stability and phase structures in the canonical and the grand canonical ensembles for these AdS braneworld black holes are described. The thermodynamic curvatures for both these AdS braneworld black holes are computed and studied as a function of the thermodynamic variables. Through this analysis we illustrate an interesting dependence of the phase structures on the braneworld parameter for these black holes.

  6. Next-Generation A/D Sampler ADS3000+ for VLBI2010

    NASA Technical Reports Server (NTRS)

    Takefuji, Kazuhiro; Takeuchi, Hiroshi; Tsutsumi, Masanori; Koyama, Yasuhiro

    2010-01-01

    A high-speed A/D sampler, called ADS3000+, has been developed in 2008, which can sample one analog signal up to 4 Gbps to versatile Linux PC. After A/D conversion, the ADS3000+ can perform digital signal processing such as real-time DBBC (Digital Base Band Conversion) and FIR filtering such as simple CW RFI filtering using the installed FPGAs. A 4 Gsps fringe test with the ADS3000+ has been successfully performed. The ADS3000+ will not exclusively be used for VLBI but will also be employed in other applications.

  7. Holographic complexity and fidelity susceptibility as holographic information dual to different volumes in AdS

    NASA Astrophysics Data System (ADS)

    Mazhari, N. S.; Momeni, Davood; Bahamonde, Sebastian; Faizal, Mir; Myrzakulov, Ratbay

    2017-03-01

    The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution, a solution with cylindrical symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not have any such dependence.

  8. Immunotherapy of allergic contact dermatitis.

    PubMed

    Spiewak, Radoslaw

    2011-08-01

    The term 'immunotherapy' refers to treating diseases by inducing, enhancing or suppressing immune responses. As allergy is an excessive, detrimental immune reaction to otherwise harmless environmental substances, immunotherapy of allergic disease is aimed at the induction of tolerance toward sensitizing antigens. This article focuses on the historical developments, present state and future outlook for immunotherapy with haptens as a therapeutic modality for allergic contact dermatitis. Inspired by the effectiveness of immunotherapy in respiratory allergies, attempts were undertaken at curing allergic contact dermatitis by means of controlled administration of the sensitizing haptens. Animal and human experiments confirmed that tolerance to haptens can be induced most effectively when the induction of tolerance precedes attempted sensitization. In real life, however, therapy is sought by people who are already sensitized and an effective reversal of hypersensitivity seems more difficult to achieve. Decades of research on Rhus hypersensitivity led to a conclusion that immunotherapy can suppress Rhus dermatitis, however, only to a limited degree, for a short period of time, and at a high risk of side effects, which makes this method therapeutically unprofitable. Methodological problems with most available studies of immunotherapy of contact allergy to nickel make any definite conclusions impossible at this stage.

  9. Nickel contact hypersensitivity in children.

    PubMed

    Silverberg, Nanette B; Licht, Jonah; Friedler, Suzanne; Sethi, Shika; Laude, Teresita A

    2002-01-01

    Nickel allergic contact dermatitis is the most prevalent allergy in North America, with an incidence of 14.3%. It is on the rise from 10 years ago, when the incidence was 10%. This has been presumed to represent an increased exposure to nickel in the environment-especially in costume jewelry and belt buckles. We examined a group of 30 pediatric patients who had either a personal history of umbilical or wrist dermatitis, or a family history of nickel allergic contact dermatitis. All of these patients had a positive patch test to nickel sulfate 5%. Moreover, 50% of patients had an id reaction; all of these patients had positive patch tests that were papular in nature, similar to their papular id reaction. We posit that the presence of a positive family history may be a positive predictor of nickel allergic contact dermatitis, requiring nickel avoidance, especially in atopic children. Based on the high level of positive reactions in patients with umbilical dermatitis and an id reaction, patch testing to nickel in these patients is most likely to yield a useful result. Knowledge of reactivity to nickel would then allow parents and patients to initiate nickel avoidance earlier in life.

  10. Cryptosporidiosis associated with animal contacts.

    PubMed

    Stantic-Pavlinic, Mirjana; Xiao, Lihua; Glaberman, Scott; Lal, Altaf A; Orazen, Toni; Rataj-Verglez, Aleksandra; Logar, Jernej; Berce, Ingrid

    2003-02-28

    Transmission of Cryptosporidium sp. within the general public was studied. We were looking for a possible risk of infection associated with animal contacts. Investigation of the animal contacts of affected individuals led to the formulation of the hypothesis that animals are a source of cryptosporidiosis. The research was done in the Region of Ljubljana, an area with 587,000 inhabitants during a period of three years. Stool specimens of 338 persons with acute enteric diseases were positive for Cryptosporidium sp. Diagnosis was done with an immunofluorescence test and modified Ziel-Neelsen staining. Processing of statistical data was done with the medical software application EPI INFO 6. According to our questionnaire, direct contact with animals occurred in 49 of the 338 cases of cryptosporidiosis, and was more frequently registered in males (Odds ratio = 1.96). Subgenotyping analysis revealed the presence of two subgenotypes of Cryptosporidium parvum bovine (GPB and GPC) in humans. These data indicate that genetic heterogeneity in C. parvum bovine genotype exists in a localized area and that farm animals can be a source of infection.

  11. [Rapid analysis of added ingredients in heroin].

    PubMed

    Wang, Ji-fen; Yu, Jing; Guo, Xin; Sun, Xing-long; Wang, Ding-fang

    2011-07-01

    The method of rapid analysis of added ingredients in heroin was studied in the present paper. Adding sucrose, fructose, glucose, starch, caffeine and phenacetin to heroin with a certain percentage, the changes in the infrared spectrum with the concentration of heroin increasing and the detection limit of the additives were determined. Whether or not heroin can be detected in the sample with high concentration of added ingredients was studied using Raman spectroscopy. Similarly, in high purity of heroin, whether or not Raman spectroscopy can detect the added ingredients was tested. Through systematic experiments, the results showed that: using infrared spectroscopy and Raman spectroscopy to test the added ingredients of heroin is a rapid and effective method. Each has both advantages and disadvantages. We should select the appropriate method according to the actual cases.

  12. The eleven observations of comets between 687 AD and 1114 AD recorded in the Anglo Saxon Chronicle

    NASA Technical Reports Server (NTRS)

    Mardon, E. G.; Williams, J.; Mardon, A. A.

    1992-01-01

    This research paper is an examination of the eleven cometary references (679AD, 729AD, 892AD, 950AD, 975AD, 995AD, 1066AD, 1097AD, 1106AD, 1110AD and 1114AD) found in the various manuscripts of The Anglo Saxon Chronicle between 678 AD and 1114 AD. The manuscripts contain more than 35 celestial observations. This is an examination of astronomical phenomena and other climatic or natural events, that are described in The Anglo Saxon Chronicle, which is also referred to as The Old English Annals.

  13. Inflation in AdS/CFT

    SciTech Connect

    Freivogel, Ben; Hubeny, Veronika E.; Maloney, Alexander; Myers, Rob; Rangamani, Mukund; Shenker, Stephen; /Stanford U., Phys. Dept.

    2005-10-07

    We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.

  14. Synaptic Contacts Enhance Cell-to-Cell Tau Pathology Propagation.

    PubMed

    Calafate, Sara; Buist, Arjan; Miskiewicz, Katarzyna; Vijayan, Vinoy; Daneels, Guy; de Strooper, Bart; de Wit, Joris; Verstreken, Patrik; Moechars, Diederik

    2015-05-26

    Accumulation of insoluble Tau protein aggregates and stereotypical propagation of Tau pathology through the brain are common hallmarks of tauopathies, including Alzheimer's disease (AD). Propagation of Tau pathology appears to occur along connected neurons, but whether synaptic contacts between neurons are facilitating propagation has not been demonstrated. Using quantitative in vitro models, we demonstrate that, in parallel to non-synaptic mechanisms, synapses, but not merely the close distance between the cells, enhance the propagation of Tau pathology between acceptor hippocampal neurons and Tau donor cells. Similarly, in an artificial neuronal network using microfluidic devices, synapses and synaptic activity are promoting neuronal Tau pathology propagation in parallel to the non-synaptic mechanisms. Our work indicates that the physical presence of synaptic contacts between neurons facilitate Tau pathology propagation. These findings can have implications for synaptic repair therapies, which may turn out to have adverse effects by promoting propagation of Tau pathology.

  15. Superradiance instability of small rotating AdS black holes in arbitrary dimensions

    NASA Astrophysics Data System (ADS)

    Delice, Ã.-zgür; Durǧut, Türküler

    2015-07-01

    We investigate the stability of D dimensional singly rotating Myers-Perry-AdS black holes under superradiance against scalar field perturbations. It is well known that small four dimensional rotating or charged Anti-de Sitter (AdS) black holes are unstable against superradiance instability of a scalar field. Recent works extended the existence of this instability to five dimensional rotating charged AdS black holes or static charged AdS black holes in arbitrary dimensions. In this paper we analytically prove that rotating small AdS black holes in arbitrary dimensions also shows superradiance instability irrespective of the value of the (positive) angular momentum quantum number. To do this we solve the Klein-Gordon equation in the slow rotation, low frequency limit. By using the asymptotic matching technique, we are able to calculate the real and imaginary parts of the correction terms to the frequency of the scalar field due to the presence of the black hole, confirming the presence of superradiance instability. We see that, unlike in the case of static AdS black holes, the analytical method is valid for rotating AdS black holes for any value of angular momentum number and spacetime dimensions. For comparison we derive the corresponding correction terms for Myers-Perry black holes in the black hole bomb formalism in the Appendix and see that the results are in agreement.

  16. Direct-Write Contacts: Metallization and Contact Formation; Preprint

    SciTech Connect

    van Hest, M. F. A. M.; Curtis, C. J.; Miedaner, A.; Pasquarelli, R. M.; Kaydonova, T.; Hersh, P.; Ginley, D. S.

    2008-05-01

    Using direct-write approaches in photovoltaics for metallization and contact formation can significantly reduce the cost per watt of producing photovoltaic devices. Inks have been developed for various materials, such as Ag, Cu, Ni and Al, which can be used to inkjet print metallizations for various kinds of photovoltaic devices. Use of these inks results in metallization with resistivities close to those of bulk materials. By means of inkjet printing a metallization grid can be printed with better resolution, i.e. smaller lines, than screen-printing. Also inks have been developed to deposit transparent conductive oxide films by means of ultrasonic spraying.

  17. Functionally gradient material for membrane reactors to convert methane gas into value-added products

    DOEpatents

    Balachandran, U.; Dusek, J.T.; Kleefisch, M.S.; Kobylinski, T.P.

    1996-11-12

    A functionally gradient material for a membrane reactor for converting methane gas into value-added-products includes an outer tube of perovskite, which contacts air; an inner tube which contacts methane gas, of zirconium oxide, and a bonding layer between the perovskite and zirconium oxide layers. The bonding layer has one or more layers of a mixture of perovskite and zirconium oxide, with the layers transitioning from an excess of perovskite to an excess of zirconium oxide. The transition layers match thermal expansion coefficients and other physical properties between the two different materials. 7 figs.

  18. Functionally gradient material for membrane reactors to convert methane gas into value-added products

    DOEpatents

    Balachandran, Uthamalingam; Dusek, Joseph T.; Kleefisch, Mark S.; Kobylinski, Thadeus P.

    1996-01-01

    A functionally gradient material for a membrane reactor for converting methane gas into value-added-products includes an outer tube of perovskite, which contacts air; an inner tube which contacts methane gas, of zirconium oxide, and a bonding layer between the perovskite and zirconium oxide layers. The bonding layer has one or more layers of a mixture of perovskite and zirconium oxide, with the layers transitioning from an excess of perovskite to an excess of zirconium oxide. The transition layers match thermal expansion coefficients and other physical properties between the two different materials.

  19. Solar cell contact formation using laser ablation

    DOEpatents

    Harley, Gabriel; Smith, David D.; Cousins, Peter John

    2015-07-21

    The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline material layer; and forming conductive contacts in the plurality of contact holes.

  20. Solar cell contact formation using laser ablation

    DOEpatents

    Harley, Gabriel; Smith, David D.; Cousins, Peter John

    2014-07-22

    The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline materiat layer; and forming conductive contacts in the plurality of contact holes.

  1. Solar cell contact formation using laser ablation

    DOEpatents

    Harley, Gabriel; Smith, David; Cousins, Peter

    2012-12-04

    The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline material layer; and forming conductive contacts in the plurality of contact holes.

  2. Space-like minimal surfaces in AdS × S

    NASA Astrophysics Data System (ADS)

    Dorn, Harald; Drukker, Nadav; Jorjadze, George; Kalousios, Chrysostomos

    2010-04-01

    We present a four parameter family of classical string solutions in AdS 3 × S 3, which end along a light-like tetragon at the boundary of AdS 3 and carry angular momentum along two cycles on the sphere. The string surfaces are space-like and their projections on AdS 3 and on S 3 have constant mean curvature. The construction is based on the Pohlmeyer reduction of the related sigma model. After embedding in AdS 5 × S 5, we calculate the regularized area and analyze conserved charges. Comments on possible relations to scattering amplitudes are presented. We also sketch time-like versions of our solutions.

  3. Quantum corrections to supergravity on AdS2×S2

    NASA Astrophysics Data System (ADS)

    Larsen, Finn; Lisbão, Pedro

    2015-04-01

    We compute the off-shell spectrum of supergravity on AdS2×S2 by explicit diagonalization of the equations of motion for an effective AdS2 theory where all fields are dualized to scalars and spin-1/2 fermions. We classify all bulk modes as physical, gauge violating, and pure gauge then compute the physical spectrum by explicit cancellation of unphysical modes. We identify boundary modes as physical fields on S2 that are formally pure gauge but with gauge function that is non-normalizable on AdS2. As an application we compute the leading quantum correction to AdS2×S2 as a sum over physical fields including boundary states. The result agrees with a previous computation by Sen [1] where unphysical modes were canceled by ghosts.

  4. The use of dimethyl sulfoxide in contact lens disinfectants is a potential preventative strategy against contracting Acanthamoeba keratitis.

    PubMed

    Siddiqui, Ruqaiyyah; Aqeel, Yousuf; Khan, Naveed Ahmed

    2016-10-01

    Acanthamoeba castellanii is the causative agent of blinding keratitis. Though reported in non-contact lens wearers, it is most frequently associated with improper use of contact lens. For contact lens wearers, amoebae attachment to the lens is a critical first step, followed by amoebae binding to the corneal epithelial cells during extended lens wear. Acanthamoeba attachment to surfaces (biological or inert) and migration is an active process and occurs during the trophozoite stage. Thus retaining amoebae in the cyst stage (dormant form) offers an added preventative measure in impeding parasite traversal from the contact lens onto the cornea. Here, we showed that as low as 3% DMSO, abolished A. castellanii excystation. Based on the findings, it is proposed that DMSO should be included in the contact lens disinfectants as an added preventative strategy against contracting Acanthamoeba keratitis.

  5. Supergravity background of the λ-deformed AdS3 × S3 supercoset

    NASA Astrophysics Data System (ADS)

    Chervonyi, Yuri; Lunin, Oleg

    2016-09-01

    We construct the solution of type IIB supergravity describing the integrable λ-deformation of the AdS3 ×S3 supercoset. While the geometry corresponding to the deformation of the bosonic coset has been found in the past, our background is more natural for studying superstrings, and several interesting features distinguish our solution from its bosonic counterpart. We also report progress towards constructing the λ-deformation of the AdS5 ×S5 supercoset.

  6. Towards an optimal contact metal for CNTFETs.

    PubMed

    Fediai, Artem; Ryndyk, Dmitry A; Seifert, Gotthard; Mothes, Sven; Claus, Martin; Schröter, Michael; Cuniberti, Gianaurelio

    2016-05-21

    Downscaling of the contact length Lc of a side-contacted carbon nanotube field-effect transistor (CNTFET) is challenging because of the rapidly increasing contact resistance as Lc falls below 20-50 nm. If in agreement with existing experimental results, theoretical work might answer the question, which metals yield the lowest CNT-metal contact resistance and what physical mechanisms govern the geometry dependence of the contact resistance. However, at the scale of 10 nm, parameter-free models of electron transport become computationally prohibitively expensive. In our work we used a dedicated combination of the Green function formalism and density functional theory to perform an overall ab initio simulation of extended CNT-metal contacts of an arbitrary length (including infinite), a previously not achievable level of simulations. We provide a systematic and comprehensive discussion of metal-CNT contact properties as a function of the metal type and the contact length. We have found and been able to explain very uncommon relations between chemical, physical and electrical properties observed in CNT-metal contacts. The calculated electrical characteristics are in reasonable quantitative agreement and exhibit similar trends as the latest experimental data in terms of: (i) contact resistance for Lc = ∞, (ii) scaling of contact resistance Rc(Lc); (iii) metal-defined polarity of a CNTFET. Our results can guide technology development and contact material selection for downscaling the length of side-contacts below 10 nm.

  7. Some Bubble and Contact Problems,

    DTIC Science & Technology

    1979-11-21

    the two points s, and I - st, with s1 to be found in the range 0< s1 < 2. Then (3.1 )holds only in the intervalsO - s <s, and I -sI < s < 1, while...0, 0(si) = r-/2, 0() = 0, J cos (s) ds= 0, 0and 0, continuous at s,. (3.4) These six conditions suffice to determine sl, R and the two integration...of the studies reported in the two preceding sections, I believed that it should be possible to obtain steeper waves by enforcing contact of adjacent

  8. Bibliometrics, dermatology and contact dermatitis.

    PubMed

    Smith, Derek R

    2008-09-01

    Although the fields of bibliometrics and citation analysis have existed for many years, relatively few studies have specifically focused on the dermatological literature. This article reviews citation-based research in the dermatology journals, with a particular interest in manuscripts that have included Contact Dermatitis as part of their analysis. Overall, it can be seen that the rise of bibliometrics during the mid-20th century and its subsequent application to dermatology has provided an interesting insight into the progression of research within our discipline. Further investigation of citation trends and top-cited papers in skin research periodicals would certainly help complement the current body of knowledge.

  9. Seeking Contact: Issues to Consider

    NASA Astrophysics Data System (ADS)

    Michaud, M.

    Seeking contact with extraterrestrial intelligence is a species enterprise that should be conducted with our shared interests in mind. We must reflect on the full range of possible outcomes; we cannot opt out of the potential consequences of actions taken by small numbers of our fellow humans. Until we have empirical evidence about alien technological civilizations, we can reason about them only by analogy with our own history and behaviour. Given that record, some degree of prudence is in order. To conduct this debate more rationally, we must free our thinking of excessively binary stereotypes.

  10. Contact dermatitis: facts and controversies.

    PubMed

    Wolf, Ronni; Orion, Edith; Ruocco, Eleonora; Baroni, Adone; Ruocco, Vincenzo

    2013-01-01

    The history of contact dermatitis (CD) is inseparable from the history of the patch test, and the patch test is inseparable from the pioneer in the field, Josef Jadassohn (1860-1936). Despite the fact that we have been diagnosing, treating, and investigating the condition for more than 100 years, there are still many unsolved questions and controversies, which show no signs of coming to an end in the foreseeable future. This contribution reviews and highlights some of the disagreements and discrepancies associated with CD. For example: • What is the real sensitizer in balsam of Peru, one of the most common allergens, and what, if any, is the value of a low-balsam diet? • Is benzalkonium chloride, which has well-known and undisputed irritant properties, a contact allergen as well? • Is cocamidopropyl betaine (CABP) a common contact allergen and what is the actual sensitizer in CABP allergy the molecule itself, or impurities, or intermediaries in its synthesis? • How can the significant differences in the prevalence of sensitization of formaldehyde (FA, a common cause of contact allergy) between the United States (8%-9%) and Europe (2%-3%) be explained? • What is the relationship between formaldehyde releasers (FRs) allergy and an FA allergy? Should we recommend that FA-allergic patients also avoid FRs, and, if so, to what extent? • What is the true frequency of lanolin allergy? This issue remains enigmatic despite the expenditure of thousands of dollars and the innumerable hours spent investigating this subject. • What is the basis behind the so-called "lanolin paradox"? This label was coined in 1996 and is still a matter of controversy. • Is there such a thing as systemic CD from nickel, and, if so, to what extent? Is there a cross-reactivity or concomitant sensitization between nickel and cobalt?These are some of the controversial problems discussed. We have selected the ones that we consider to be of special interest and importance to the

  11. Frictionless contact of aircraft tires

    NASA Technical Reports Server (NTRS)

    Kim, Kyun O.; Tanner, John A.; Noor, Ahmed K.

    1989-01-01

    A computational procedure for the solution of frictionless contact problems of spacecraft tires was developed using a two-dimensional laminated anisotropic shell theory incorporating the effects of variations in material and geometric parameters, transverse shear deformation, and geometric nonlinearities to model the nose-gear tire of a space shuttle. Numerical results are presented for the case when the nose-gear tire is subjected to inflation pressure and pressed against a rigid pavement. The results are compared with experimental results obtained at NASA Langley, demonstrating a high accuracy of the model and the effectiveness of the computational procedure.

  12. Residual contact restraints in cryogenics

    NASA Astrophysics Data System (ADS)

    Cretegny, J. F.; Demonicault, J. M.

    The use of residual stress measurements to evaluate the state of cryogenic turbomachines, whose surfaces are worn by the working conductions in dry contact, is addressed. Their contribution to the understanding of the reasons of possible ruptures is considered. It is stated that residual stress measurements should be used as a complementary tool rather than as input data for models. It is shown, thanks to two examples concerning the ball bearings and splines of the liquid hydrogen turbopump of the Vulcain engine, what can be expected from such techniques. Total exploitation of the results has still to be done, but preliminary results are quite encouraging.

  13. Allergic contact dermatitis to chloroxylenol.

    PubMed

    Berthelot, Cindy; Zirwas, Matthew J

    2006-09-01

    Chloroxylenol, also known as p-chloro-m-xylenol (PCMX), is a compound that has been used as a preservative in cosmetics and as an active agent in antimicrobial soaps. We present two patients with allergic contact dermatitis from PCMX, confirmed by positive (+++) patch-test reactions at 48 and 72 hours, identification of PCMX in a soap and in a hand cream used by the patients, and improvement following withdrawal of the incriminating products. The mechanism of action, structure, antimicrobial activity, and dangers of PCMX are reviewed.

  14. Thermal Conductances Of Metal Contacts

    NASA Technical Reports Server (NTRS)

    Salerno, L. J.; Kittel, P.; Scherkenbach, F. E.; Spivak, A. L.

    1988-01-01

    Report presents results of measurements of thermal conductances of aluminum and stainless-steel contacts at temperatures from 1.6 to 6.0 K. Measurement apparatus includes gearmotor assembly connected to rocker arm by music wire to load sample pair with forces up to 670 N. Heater placed above upper sample. Germanium resistance thermometers in upper and lower samples measured temperature difference across interface over range of heater powers from 0.1 to 10.0 mW. The thermal conductance calculated from temperature difference. Measurements provide data for prediction of thermal conductances of bolted joints in cryogenic infrared instruments.

  15. Contact stresses calculated for miniature slip rings

    NASA Technical Reports Server (NTRS)

    Albright, F. G.; Domerest, K. E.; Horton, J. C.

    1965-01-01

    Using mathematical formulations to plot the graphs of the contact preload versus the Hertzian load, calculations of unit loading of the preloaded brushes on slip rings can be made. This optimizes the design of contact brushes and miniature slip rings.

  16. Clean Cities Program Contacts (Fact Sheet)

    SciTech Connect

    Not Available

    2012-03-01

    This fact sheet provides contact information for program staff of the U.S. Department of Energy's Clean Cities program, as well as contact information for the nearly 100 local Clean Cities coalitions across the country.

  17. Ensuring Safe Use of Contact Lens Solution

    MedlinePlus

    ... For Consumers Consumer Updates Ensuring Safe Use of Contact Lens Solution Share Tweet Linkedin Pin it More ... back to top Dos and Don'ts for Contact Lens Wearers DO: Always wash your hands before ...

  18. Inferring Epidemic Contact Structure from Phylogenetic Trees

    PubMed Central

    Leventhal, Gabriel E.; Kouyos, Roger; Stadler, Tanja; von Wyl, Viktor; Yerly, Sabine; Böni, Jürg; Cellerai, Cristina; Klimkait, Thomas; Günthard, Huldrych F.; Bonhoeffer, Sebastian

    2012-01-01

    Contact structure is believed to have a large impact on epidemic spreading and consequently using networks to model such contact structure continues to gain interest in epidemiology. However, detailed knowledge of the exact contact structure underlying real epidemics is limited. Here we address the question whether the structure of the contact network leaves a detectable genetic fingerprint in the pathogen population. To this end we compare phylogenies generated by disease outbreaks in simulated populations with different types of contact networks. We find that the shape of these phylogenies strongly depends on contact structure. In particular, measures of tree imbalance allow us to quantify to what extent the contact structure underlying an epidemic deviates from a null model contact network and illustrate this in the case of random mixing. Using a phylogeny from the Swiss HIV epidemic, we show that this epidemic has a significantly more unbalanced tree than would be expected from random mixing. PMID:22412361

  19. Piecing Together the Patchwork of Contact Sites.

    PubMed

    Gatta, Alberto T; Levine, Tim P

    2017-03-01

    Contact sites are places where two organelles join together to carry out a shared activity requiring nonvesicular communication. A large number of contact sites have been discovered, and almost any two organelles can contact each other. General rules about contacts include constraints on bridging proteins, with only a minority of bridges physically creating contacts by acting as 'tethers'. The downstream effects of contacts include changing the physical behaviour of organelles, and also forming biochemically heterogeneous subdomains. However, some functions typically localized to contact sites, such as lipid transfer, have no absolute requirement to be situated there. Therefore, the key aspect of contacts is the directness of communication, which allows metabolic channelling and collective regulation.

  20. Inferring epidemic contact structure from phylogenetic trees.

    PubMed

    Leventhal, Gabriel E; Kouyos, Roger; Stadler, Tanja; Wyl, Viktor von; Yerly, Sabine; Böni, Jürg; Cellerai, Cristina; Klimkait, Thomas; Günthard, Huldrych F; Bonhoeffer, Sebastian

    2012-01-01

    Contact structure is believed to have a large impact on epidemic spreading and consequently using networks to model such contact structure continues to gain interest in epidemiology. However, detailed knowledge of the exact contact structure underlying real epidemics is limited. Here we address the question whether the structure of the contact network leaves a detectable genetic fingerprint in the pathogen population. To this end we compare phylogenies generated by disease outbreaks in simulated populations with different types of contact networks. We find that the shape of these phylogenies strongly depends on contact structure. In particular, measures of tree imbalance allow us to quantify to what extent the contact structure underlying an epidemic deviates from a null model contact network and illustrate this in the case of random mixing. Using a phylogeny from the Swiss HIV epidemic, we show that this epidemic has a significantly more unbalanced tree than would be expected from random mixing.

  1. Testing the AdS/CFT Correspondence

    SciTech Connect

    Klebanov, Igor R.

    2008-07-28

    This lecture begins with some history and basic facts about string theory and its connections with strong interactions. Comparisons of stacks of Dirichlet branes with curved backgrounds produced by them are used to motivate the AdS/CFT correspondence between superconformal gauge theory and string theory on a product of Anti-de Sitter space and a compact manifold. The ensuing duality between semi-classical spinning strings and long gauge theory operators is briefly reviewed. We go on to describe a recent test of the AdS/CFT correspondence using the Wilson loop cusp anomaly as a function of the coupling, which also enters dimensions of high-spin operators. Finally, strongly coupled thermal SYM theory is explored via a black hole in 5-dimensional AdS space, which leads to explicit results for its entropy and shear viscosity.

  2. The Recent Data Explosion in the ADS

    NASA Astrophysics Data System (ADS)

    Grant, Carolyn S.; Accomazzi, A.; Henneken, E.; Thompson, D.; Kurtz, M. J.; Murray, S. S.

    2007-12-01

    In the past 12 months, we have added over a million records to the ADS Abstract Service. This is the equivalent of a 20% increase, or about double the rate of increase that the ADS has seen in recent years. This significant increase in size is due to the addition of several large datasets including historical data from many Springer astronomy and physics journals as well as bibliographic records from the full run of A&A Abstracts from the Astronomisches Rechen-Institut. The number of citations in the Abstract Service has seen an increase of more than 25%, bringing the total number of citations to over 25 million. Our recent agreement to index records from CrossRef will continue the data explosion in the ADS into 2008.

  3. Microbial production of value-added nutraceuticals.

    PubMed

    Wang, Jian; Guleria, Sanjay; Koffas, Mattheos A G; Yan, Yajun

    2016-02-01

    Nutraceuticals are important natural bioactive compounds that confer health-promoting and medical benefits to humans. Globally growing demands for value-added nutraceuticals for prevention and treatment of human diseases have rendered nutraceuticals a multi-billion dollar market. However, supply limitations and extraction difficulties from natural sources such as plants, animals or fungi, restrict the large-scale use of nutraceuticals. Metabolic engineering via microbial production platforms has been advanced as an eco-friendly alternative approach for production of value-added nutraceuticals from simple carbon sources. Microbial platforms like the most widely used Escherichia coli and Saccharomyces cerevisiae have been engineered as versatile cell factories for production of diverse and complex value-added chemicals such as phytochemicals, prebiotics, polysaccaharides and poly amino acids. This review highlights the recent progresses in biological production of value-added nutraceuticals via metabolic engineering approaches.

  4. High efficiency wraparound contact solar cells /HEWACS/

    NASA Technical Reports Server (NTRS)

    Gillanders, M.; Opjorden, R.

    1980-01-01

    A cell technology, producing high efficiency wrap-around contact solar cells (HEWACS), with both electrical contacts on the back and AMO conversion efficiencies of almost 15%, is presented. A flow chart indicating the baseline process sequence along with the process changes is given. Tests checking for coating delamination and contact integrity, those measuring contact strength, and thermal cycle tests, successfully demonstrated that this cell technology is ready to be moved to the pilot production stage.

  5. Microscale hydrodynamics near moving contact lines

    NASA Technical Reports Server (NTRS)

    Garoff, Stephen; Chen, Q.; Rame, Enrique; Willson, K. R.

    1994-01-01

    The hydrodynamics governing the fluid motions on a microscopic scale near moving contact lines are different from those governing motion far from the contact line. We explore these unique hydrodynamics by detailed measurement of the shape of a fluid meniscus very close to a moving contact line. The validity of present models of the hydrodynamics near moving contact lines as well as the dynamic wetting characteristics of a family of polymer liquids are discussed.

  6. Adding stress plot function to NASTRAN

    NASA Technical Reports Server (NTRS)

    Katoh, S.

    1978-01-01

    Stress plot function was developed and added to the NASTRAN level 15.5. Computed stress distribution can be displayed by this function, with vectors showing the principal stresses of the finite elements over the specified portions of the structure. NASTRAN is reviewed in the aspect of plotting capabilities. Stress tensor field is examined in preparation of stress display. Then the stress plot function as added to the NASTRAN is described. A sample plotout by this function is shown.

  7. Image Ads and Issue Ads in U.S. Presidential Advertising: Using Videostyle To Explore Stylistic Differences in Televised Political Ads From 1952 to 2000.

    ERIC Educational Resources Information Center

    Johnston, Anne; Kaid, Lynda Lee

    2002-01-01

    Explores the differences in techniques, strategies, narratives, and symbols used in 1,213 television issue ads and image ads from 13 U.S. presidential campaigns. Concludes that although the majority of both types of ads were positive, negative appeals dominated a higher percentage of issue ads as compared with image ads. (SG)

  8. Techniques for Solution- Assisted Optical Contacting

    NASA Technical Reports Server (NTRS)

    DeVine, Glenn; Ware, Brent; Wuchenich, Danielle M.; Spero, Robert E.; Klipstein, William M.; McKenzie, Kirk

    2012-01-01

    A document discusses a solution-assisted contacting technique for optical contacting. An optic of surface flatness Lambda/20 was successfully contacted with one of moderate surface quality, or Lambda/4. Optics used were both ultra-low expansion (ULE) glass (Lambda/4 and Lambda/20) and fused silica (Lambda/20). A stainless steel template of the intended interferometer layout was designed and constructed with three contact points per optic. The contact points were all on a common side of the template. The entire contacting jig was tilted at about 30 . Thus, when the isopropanol was applied, each optic slid due to gravity, resting on the contact points. All of the contacting was performed in a relatively dusty laboratory. A number of successful contacts were achieved where up to two or three visible pieces of dust could be seen. These were clearly visible due to refraction patterns between the optic and bench. On a number of optics, the final step of dropping isopropyl between the surfaces was repeated until a successful contact was achieved. The new procedures realized in this work represent a simplification for optical contacting in the laboratory. They will both save time and money spent during the contacting process, and research and development phases. The techniques outlined are suitable for laboratory experiments, research, and initial development stages.

  9. Sinterless Formation Of Contacts On Indium Phosphide

    NASA Technical Reports Server (NTRS)

    Weizer, Victor G.; Fatemi, Navid S.

    1995-01-01

    Improved technique makes it possible to form low-resistivity {nearly equal to 10(Sup-6) ohm cm(Sup2)} electrical contacts on indium phosphide semiconductor devices without damaging devices. Layer of AgP2 40 Angstrom thick deposited on InP before depositing metal contact. AgP2 interlayer sharply reduces contact resistance, without need for sintering.

  10. 7 CFR 1737.10 - Initial contact.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Initial contact. 1737.10 Section 1737.10 Agriculture... Preapplication Stage § 1737.10 Initial contact. Initial loan applicants seeking assistance should write the Rural.... Existing borrowers initiate the contact directly with their assigned field representative....

  11. 7 CFR 1737.10 - Initial contact.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Initial contact. 1737.10 Section 1737.10 Agriculture... Preapplication Stage § 1737.10 Initial contact. Initial loan applicants seeking assistance should write the Rural.... Existing borrowers initiate the contact directly with their assigned field representative....

  12. 7 CFR 1737.10 - Initial contact.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Initial contact. 1737.10 Section 1737.10 Agriculture... Preapplication Stage § 1737.10 Initial contact. Initial loan applicants seeking assistance should write the Rural.... Existing borrowers initiate the contact directly with their assigned field representative....

  13. 7 CFR 1710.400 - Initial contact.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Initial contact. 1710.400 Section 1710.400... Requirements and Procedures for Loans § 1710.400 Initial contact. (a) Loan applicants that do not have... outstanding loans should contact their assigned RUS general field representative (GFR) or, in the case of...

  14. 7 CFR 1710.400 - Initial contact.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Initial contact. 1710.400 Section 1710.400... Requirements and Procedures for Loans § 1710.400 Initial contact. (a) Loan applicants that do not have... outstanding loans should contact their assigned RUS general field representative (GFR) or, in the case of...

  15. 7 CFR 1710.400 - Initial contact.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Initial contact. 1710.400 Section 1710.400... Requirements and Procedures for Loans § 1710.400 Initial contact. (a) Loan applicants that do not have... outstanding loans should contact their assigned RUS general field representative (GFR) or, in the case of...

  16. 7 CFR 1737.10 - Initial contact.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Initial contact. 1737.10 Section 1737.10 Agriculture... Preapplication Stage § 1737.10 Initial contact. Initial loan applicants seeking assistance should write the Rural.... Existing borrowers initiate the contact directly with their assigned field representative....

  17. 7 CFR 1737.10 - Initial contact.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Initial contact. 1737.10 Section 1737.10 Agriculture... Preapplication Stage § 1737.10 Initial contact. Initial loan applicants seeking assistance should write the Rural.... Existing borrowers initiate the contact directly with their assigned field representative....

  18. 7 CFR 1710.400 - Initial contact.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Initial contact. 1710.400 Section 1710.400... Requirements and Procedures for Loans § 1710.400 Initial contact. (a) Loan applicants that do not have... outstanding loans should contact their assigned RUS general field representative (GFR) or, in the case of...

  19. 7 CFR 1710.400 - Initial contact.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Initial contact. 1710.400 Section 1710.400... Requirements and Procedures for Loans § 1710.400 Initial contact. (a) Loan applicants that do not have... outstanding loans should contact their assigned RUS general field representative (GFR) or, in the case of...

  20. Substantially oxygen-free contact tube

    NASA Technical Reports Server (NTRS)

    Pike, James F. (Inventor)

    1993-01-01

    A device for arc welding is provided in which a continuously-fed electrode wire is in electrical contact with a contact tube. The contact tube is improved by using a substantially oxygen-free conductive alloy in order to reduce the amount of electrical erosion.

  1. Substantially Oxygen-Free Contact Tube

    NASA Technical Reports Server (NTRS)

    Pike, James F. (Inventor)

    1991-01-01

    A device for arc welding is provided in which a continuously-fed electrode wire is in electrical contact with a contact tube. The contact tube is improved by using a substantially oxygen-free conductive alloy in order to reduce the amount of electrical erosion.

  2. Spectral flow dissipation in superconducting point contacts.

    SciTech Connect

    Kopnin, N. B.; Vinokur, V. M.; Materials Science Division; Helsinki Univ. of Technology; L. D. Landau Inst. for Theoretical Physics

    2003-03-15

    We find that multiple Andreev reflections mediating the transport in superconducting point contacts are strongly affected by a small amount of impurities in the area of the contact. We also argue that the model based on Zener transitions within independent conducting channels is not suitable for kinetic processes in multichannel contacts.

  3. [Contact allergies in the elderly].

    PubMed

    Mahler, V

    2015-09-01

    The percentage of seniors (> 65 years of age) in the general population continues to rise. Their sensitization profile may be influenced by lifelong work-related and nonwork-related exposures and comorbidities requiring local or systemic treatment. Recent analysis of the IVDK (Information Network of Departments of Dermatology) cohort concerning the most frequently recognized contact allergens in the age group above 65 (2009-2013: N = 14,841) revealed significant differences compared to the age group up to 65 years of age. The top 10 contact allergens recognized in individuals older than 65 years were the following: fragrance mix, Myroxylon pereirae (Balsam of Peru), nickel (II) sulfate, fragrance mix II, colophony, propolis, methylchloroisothiazolinone/methylisothiazolinone (MCI/MI), lanolin alcohol, Amerchol L 101, tert-butylhydroquinone. Sensitization to nickel was significantly less frequent, while sensitizations to fragrance mix and Balsam of Peru were significantly more frequent than in the age group up to 65 years of age. The percentage of patients with leg dermatitis was 25.9 % in the age group above 65 (versus 5.8 % in the age group up to 65 years of age). The analysis of the subgroup over 65 years of age with and without ulcer/stasis dermatitis/chronic venous insufficiency displayed remarkable differences in sensitization frequencies against ingredients of topical ointments (lanolin alcohol, Amerchol L 101, and tert-butylhydroquinone). If these comorbidities exist, patch testing of the topical ointment series parallel to the standard series is worthwhile.

  4. Relaxation damping in oscillating contacts

    PubMed Central

    Popov, M.; Popov, V.L.; Pohrt, R.

    2015-01-01

    If a contact of two purely elastic bodies with no sliding (infinite coefficient of friction) is subjected to superimposed oscillations in the normal and tangential directions, then a specific damping appears, that is not dependent on friction or dissipation in the material. We call this effect “relaxation damping”. The rate of energy dissipation due to relaxation damping is calculated in a closed analytic form for arbitrary axially-symmetric contacts. In the case of equal frequency of normal and tangential oscillations, the dissipated energy per cycle is proportional to the square of the amplitude of tangential oscillation and to the absolute value of the amplitude of normal oscillation, and is dependent on the phase shift between both oscillations. In the case of low frequency tangential oscillations with superimposed high frequency normal oscillations, the dissipation is proportional to the ratio of the frequencies. Generalization of the results for macroscopically planar, randomly rough surfaces as well as for the case of finite friction is discussed. PMID:26549011

  5. Contact dermatitis from a prosthesis.

    PubMed

    Munoz, Carla A; Gaspari, Anthony; Goldner, Ronald

    2008-01-01

    Patients wearing a prosthesis face a wide variety of medical problems. Skin complications have long been recognized, but their prevalence is still unknown. The most frequently reported disorders are allergic contact dermatitis (ACD), acroangiodermatitis, epidermoid cysts, epidermal hyperplasia, follicular hyperkeratosis, verrucous hyperplasia, bullous diseases, hyperhidrosis, infections, malignancies, and ulcerations. Contact dermatitis represents one-third of the dermatoses in amputees wearing prostheses. All patients who are suspected of having ACD should be patch tested with standard allergen series as well as materials from the patient's own prosthesis, topical medicaments, moisturizers, and cosmetics. We report a patient with an ACD to mixed dialkyl thiourea present in the rubber parts of his below-the-knee prosthesis. Thiourea derivates are used as accelerators in the manufacture of chloroprene rubber and as fixatives in photography and photocopy paper. Allergy to thiourea is relatively uncommon; different studies have shown a prevalence of 0.7% up to 2.4% in patch-tested patients. Thiourea derivates are often the allergic sources in ACD involving high-grade rubber products made of neoprene such as diving suits, protective goggles, knee braces, and continuous positive airway pressure masks. They are also present in the rubber material of prostheses, as in the case of our patient.

  6. Obituary--rigid contact lenses.

    PubMed

    Efron, Nathan

    2010-10-01

    Scleral and corneal rigid lenses represented 100 per cent of the contact lens market immediately prior to the invention of soft lenses in the mid-1960s. In the United Kingdom today, rigid lenses comprise 2 per cent of all new lens fits. Low rates of rigid lens fitting are also apparent in 27 other countries which have recently been surveyed. Thus, the 1998 prediction of the author that rigid lenses--also referred to as 'rigid gas permeable' (RGP) lenses or 'gas permeable' (GP) lenses--would be obsolete by the year 2010 has essentially turned out to be correct. In this obituary, the author offers 10 reasons for the demise of rigid lens fitting: initial rigid lens discomfort; intractable rigid lens-induced corneal and lid pathology; extensive soft lens advertising; superior soft lens fitting logistics; lack of rigid lens training opportunities; redundancy of the rigid lens 'problem solver' function; improved soft toric and bifocal/varifocal lenses; limited uptake of orthokeratology; lack of investment in rigid lenses; and the emergence of aberration control soft lenses. Rigid lenses are now being fitted by a minority of practitioners with specialist skills/training. Certainly, rigid lenses can no longer be considered as a mainstream form of contact lens correction. May their dear souls (bulk properties) rest in peace.

  7. Contact Printing of Arrayed Microstructures

    PubMed Central

    Xu, Wei; Luikart, Alicia M.; Sims, Christopher E.; Allbritton, Nancy L.

    2010-01-01

    A novel contact printing method utilizing a sacrificial layer of polyacrylic acid (PAA) was developed to selectively modify the upper surfaces of arrayed microstructures. The method was characterized by printing polystyrene onto SU-8 microstructures to create an improved substrate for a cell-based microarray platform. Experiments measuring cell growth SU-8 arrays modified with polystyrene and fibronectin demonstrated improved growth of NIH 3T3 (93% vs. 38%), HeLa (97% vs. 77%), and HT1080 (76% vs. 20%) cells relative to that for the previously used coating method. In addition, use of the PAA sacrificial layer permitted the printing of functionalized polystyrene, carboxylate polystyrene nanospheres, and silica nanospheres onto the arrays in a facile manner. Finally, a high concentration of extracellular matrix materials (ECM), such as collagen (5 mg/mL) and gelatin (0.1%), was contact printed onto the array structures using as little as 5 μL of the ECM reagent and without the formation of a continuous film bridge across the microstructures. Murine embryonic stem cells cultured on arrays printed with this gelatin-hydrogel remained in an undifferentiated state indicating an adequate surface gelatin layer to maintain these cells over time. PMID:20425106

  8. Rolling Contact Fatigue of Ceramics

    SciTech Connect

    Wereszczak, Andrew A; Wang, W.; Wang, Y.; Hadfield, M.; Kanematsu, W.; Kirkland, Timothy Philip; Jadaan, Osama M.

    2006-09-01

    High hardness, low coefficient of thermal expansion and high temperature capability are properties also suited to rolling element materials. Silicon nitride (Si{sub 3}N{sub 4}) has been found to have a good combination of properties suitable for these applications. However, much is still not known about rolling contact fatigue (RCF) behavior, which is fundamental information to assess the lifetime of the material. Additionally, there are several test techniques that are employed internationally whose measured RCF performances are often irreconcilable. Due to the lack of such information, some concern for the reliability of ceramic bearings still remains. This report surveys a variety of topics pertaining to RCF. Surface defects (cracks) in Si{sub 3}N{sub 4} and their propagation during RCF are discussed. Five methods to measure RCF are then briefly overviewed. Spalling, delamination, and rolling contact wear are discussed. Lastly, methods to destructively (e.g., C-sphere flexure strength testing) and non-destructively identify potential RCF-limiting flaws in Si{sub 3}N{sub 4} balls are described.

  9. AdS5×S(5) mirror model as a string sigma model.

    PubMed

    Arutyunov, Gleb; van Tongeren, Stijn J

    2014-12-31

    Doing a double Wick rotation in the world sheet theory of the light cone AdS5×S(5) superstring results in an inequivalent, so-called mirror theory that plays a central role in the field of integrability in the AdS-CFT correspondence. We show that this mirror theory can be interpreted as the light cone theory of a free string on a different background. This background is related to dS5×H(5) by a double T-duality, and has hidden supersymmetry. The geometry can also be extracted from an integrable deformation of the AdS5×S(5) sigma model, and we prove the observed mirror duality of these deformed models at the bosonic level as a byproduct. While we focus on AdS5×S(5), our results apply more generally.

  10. Activation of the factor XII-driven contact system in Alzheimer’s disease patient and mouse model plasma

    PubMed Central

    Zamolodchikov, Daria; Chen, Zu-Lin; Conti, Brooke A.; Renné, Thomas; Strickland, Sidney

    2015-01-01

    Alzheimer’s disease (AD) is characterized by accumulation of the β-amyloid peptide (Aβ), which likely contributes to disease via multiple mechanisms. Increasing evidence implicates inflammation in AD, the origins of which are not completely understood. We investigated whether circulating Aβ could initiate inflammation in AD via the plasma contact activation system. This proteolytic cascade is triggered by the activation of the plasma protein factor XII (FXII) and leads to kallikrein-mediated cleavage of high molecular-weight kininogen (HK) and release of proinflammatory bradykinin. Aβ has been shown to promote FXII-dependent cleavage of HK in vitro. In addition, increased cleavage of HK has been found in the cerebrospinal fluid of patients with AD. Here, we show increased activation of FXII, kallikrein activity, and HK cleavage in AD patient plasma. Increased contact system activation is also observed in AD mouse model plasma and in plasma from wild-type mice i.v. injected with Aβ42. Our results demonstrate that Aβ42-mediated contact system activation can occur in the AD circulation and suggest new pathogenic mechanisms, diagnostic tests, and therapies for AD. PMID:25775543

  11. Pore corrosion model for gold-plated copper contacts.

    SciTech Connect

    Moffat, Harry K.; Sun, Amy Cha-Tien; Glauner, Carly S.; Enos, David George

    2005-04-01

    The goal of this study is to model the electrical response of gold plated copper electrical contacts exposed to a mixed flowing gas stream consisting of air containing 10ppb H2S at 30 C and a relative humidity of 70%. This environment accelerates the attack normally observed in a light industrial environment (essentially a simplified version of the Battelle class 2 environment). Corrosion rates were quantified by measuring the corrosion site density, size distribution, and the macroscopic electrical resistance of the aged surface as a function of exposure time. A pore corrosion numerical model was used to predict both the growth of copper sulfide corrosion product which blooms through defects in the gold layer and the resulting electrical contact resistance of the aged surface. Assumptions about the distribution of defects in the noble metal plating and the mechanism for how corrosion blooms affect electrical contact resistance were needed to close the numerical model. Comparisons are made to the experimentally observed number density of corrosion sites, the size distribution of corrosion product blooms, and the cumulative probability distribution of the electrical contact resistance. Experimentally, the bloom site density increases as a function of time, whereas the bloom size distribution remains relatively independent of time. These two effects are included in the numerical model by adding a corrosion initiation probability proportional to the surface area along with a probability for bloom-growth extinction proportional to the corrosion product bloom volume. The cumulative probability distribution of electrical resistance becomes skewed as exposure time increases. While the electrical contact resistance increases as a function of time for a fraction of the bloom population, the median value remains relatively unchanged. In order to model this behavior, the resistance calculated for large blooms has been weighted more heavily.

  12. Tooth displacement due to occlusal contacts: a three-dimensional finite element study.

    PubMed

    Gomes de Oliveira, S; Seraidarian, P I; Landre, J; Oliveira, D D; Cavalcanti, B N

    2006-12-01

    The use of the Finite Element Method (FE) is an appropriate way to study occlusal forces and tooth movement. The purpose of this study was to evaluate the effects of different occlusal contact patterns on tooth displacement in an adult dentition using a three-dimensional FE model of a human maxilla and mandible. Initially, images of a computerized tomography scan were redrawn in a computer program (CATIA) followed by the FE mesh construction. The MSC/Patran software was used to develop the FE mesh comprising 520,445 elements and 106,633 nodes. The MSC/Nastran program was utilized as pre and post-processor for all mathematical calculations necessary to evaluate dental and mandibular biomechanics. Four occlusal patterns were tested: FEM 1 - standard occlusal contacts; FEM 2 - removal of mesial marginal and mesial tripoidism contacts; FEM 3 - removal of distal marginal and distal tripoidism contacts; FEM 4 - similar to FEM 3 with added contacts between upper and lower incisors. Small changes in the standard distribution of occlusal contacts resulted in an imbalance of occlusal forces and changes in dental positioning. All simulations tested showed mesial displacement of posterior teeth. The most significant changes were registered in the model presenting unstable occlusal contacts when the anterior teeth were in occlusion (FEM 4). These findings may explain mandibular incisors crowding and maxillary incisors flaring as a result of small variations in dental contacts.

  13. Dynamics of solid dispersions in oil during the lubrication of point contacts. Part 1: Graphite

    NASA Technical Reports Server (NTRS)

    Cusano, C.; Sliney, H. E.

    1981-01-01

    A Hertzian contact was lubricated with dispersed graphite in mineral oils under boundary lubrication conditions. The contact was optically observed under pure rolling, combined rolling and sliding, and pure sliding conditions. The contact was formed with a steel ball on the flat surface of a glass disk. Photomicrographs are presented which show the distribution of the graphite in and around the contact. Friction and surface damage are also shown for conditions when the base oils are used alone and when graphite is added to the base oils. Under pure rolling and combined rolling and sliding conditions, it is found that, for low speeds, a graphite film can form which will separate the contacting surfaces. Under pure sliding conditions, graphite accumulates at the inlet and sweeps around the contact, but very little of the graphite passes through the contact. The accumulated graphite appears to act as a barrier which reduces the supply of oil available to the contact for boundary lubrication. Friction data show no clear short term beneficial or detrimental effect caused by addition of graphite to the base oil. However, during pure sliding, more abrasion occurs on the polished balls lubricated with the dispersion than on those lubricated with the base oil alone. All observations were for the special case of a highly-polished ball on a glass surface and may not be applicable to other geometries and materials, or to rougher surfaces.

  14. Contact Stress of Modified Curvilinear Gears

    NASA Astrophysics Data System (ADS)

    Chen, Yi-Cheng; Gu, Ming-Lune

    2010-10-01

    The contact characteristics of a modified curvilinear gear set were investigated based on finite element analysis in this study. Firstly, the mathematical model of the modified curvilinear gears was developed based on the theory of gearing. Then a solid model of a modified curvilinear gear set was built by utilizing computer-aided design software. Finite element analysis enabled us to investigate the contact stress of a contact teeth pair. The variation and distribution of the contact stresses and bending stresses are also studied under different gear design parameters. Finally, illustrative examples were presented to demonstrate the contact characteristics of the modified curvilinear gears.

  15. Histomorphology and Immunophenotype of Eczematous Skin Lesions Revisited-Skin Biopsies Are Not Reliable in Differentiating Allergic Contact Dermatitis, Irritant Contact Dermatitis, and Atopic Dermatitis.

    PubMed

    Frings, Verena G; Böer-Auer, Almut; Breuer, Kristine

    2017-03-10

    Lesions of allergic contact dermatitis (ACD), irritant contact dermatitis (ICD), and atopic dermatitis (AD) share similar clinical features and thus, their diagnosis can be challenging. The aim of this study was to reassess histopathology and immunophenotyping properties to distinguish between ACD, ICD, and AD. Charts of patients with eczema, who had undergone complete routine diagnostic workup (skin biopsies, patch tests, skin prick tests, and respectively or serum IgE levels), were reviewed. Thirty-five skin biopsy specimens of 28 patients (mean age 64 ± 15 years; ♀ = 13 ♂ = 15) with clear diagnosis of ACD (n = 15), ICD (n = 6), or AD (n = 14) were analyzed. Histomorphological and immunohistochemical (CD3, CD4, CD8, CD11c, CD34, CD123, S100, and IL-17) parameters were evaluated using Kruskal-Wallis test, Wilcoxon test, Fisher exact test, and decision tree analysis. Eosinophils were statistically significant (P = 0.0184), more often observed in AD than in ACD or ICD. No other statistically significant differences were found with regard to epidermal patterns, patterns of dermal infiltrates, or immunophenotyping. Using predictive modeling approaches, dermal eosinophils were found to be associated with AD, necrotic epidermal keratinocytes with ICD, and a focal type of parakeratosis with ACD. As an additional finding, pseudo-Pautrier microabscesses, which were present in the skin of 2 AD and 2 ACD patients, contained myeloid dendritic cells (CD11c-+). Differentiation of ACD, ICD, and AD should be based on clinical features and results of allergy tests. Histopathology does not reliably differentiate between ACD, ICD, and AD, but helps to exclude psoriasis, tinea, or T-cell lymphoma.

  16. Supersymmetric wrapped membranes, AdS2 spaces, and bubbling geometries

    NASA Astrophysics Data System (ADS)

    MacConamhna, Oisín A. P.; Colgáin, Eoin Ó.

    2007-03-01

    We perform a systematic study, in eleven dimensional supergravity, of the geometry of wrapped brane configurations admitting AdS2 limits. Membranes wrapping holomorphic curves in Calabi-Yau manifolds are found to exhibit some novel features; in particular, for fourfolds or threefolds, the gravitational effect of the branes on the overall transverse space is only weakly restricted by the kinematics of the Killing spinor equation. We also study the AdS2 limits of the wrapped brane supergravity descriptions. For membranes wrapped in a two-fold, we derive a set of AdS2 supersymmetry conditions which upon analytic continuation coincide precisely with those for the half-BPS bubbling geometries of LLM. From membranes wrapped in a three-fold, we obtain a set of AdS2 supersymmetry conditions which upon analytic continuation describe a class of spacetimes which we identify as quarter-BPS bubbling geometries in M-theory, with SO(4) × SO(3) × U(1) isometry in Riemannian signature. We also study fivebranes wrapping a special lagrangian five-cycle in a fivefold, in the presence of membranes wrapping holomorphic curves, and employ the wrapped brane supersymmetry conditions to derive a classification of the general minimally supersymmetric AdS2 geometry in M-theory.

  17. AdS and Lifshitz scalar hairy black holes in Gauss-Bonnet gravity

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Fan, Zhong-Ying; Zhu, Lu-Yao

    2016-09-01

    We consider Gauss-Bonnet (GB) gravity in general dimensions, which is nonminimally coupled to a scalar field. By choosing a scalar potential of the type V (ϕ )=2 Λ0+1/2 m2ϕ2+γ4ϕ4 , we first obtain large classes of scalar hairy black holes with spherical/hyperbolic/planar topologies that are asymptotic to locally anti- de Sitter (AdS) space-times. We derive the first law of black hole thermodynamics using Wald formalism. In particular, for one class of the solutions, the scalar hair forms a thermodynamic conjugate with the graviton and nontrivially contributes to the thermodynamical first law. We observe that except for one class of the planar black holes, all these solutions are constructed at the critical point of GB gravity where there exist unique AdS vacua. In fact, a Lifshitz vacuum is also allowed at the critical point. We then construct many new classes of neutral and charged Lifshitz black hole solutions for an either minimally or nonminimally coupled scalar and derive the thermodynamical first laws. We also obtain new classes of exact dynamical AdS and Lifshitz solutions which describe radiating white holes. The solutions eventually become AdS or Lifshitz vacua at late retarded times. However, for one class of the solutions, the final state is an AdS space-time with a globally naked singularity.

  18. Implementation of Recursion Relations in Gluon Scattering Amplitude Calculations in AdS4 /CFT3

    NASA Astrophysics Data System (ADS)

    Dokmetzoglou, Nikolaos; Kharel, Savan

    2017-01-01

    The Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence is a duality between a theory of gravity in curved-space (AdS) and a conformally-invariant quantum field theory in flat-space (CFT). Scattering amplitudes are observables associated with the probability of the interaction of a given assembly of particles. Gluons, being the exchange particles associated with the strong nuclear force, which holds quarks together to form protons, are abundant byproducts of fundamental particle collisions. Thus, studying gluon scattering amplitudes is an effective way of deepening our understanding of these observables in AdS/CFT. Traditionally, Feynman diagrams have been used to calculate such scattering amplitudes. In this project, we use factorization properties and recursion relations to simplify these calculations. More specifically, we calculate multiple (different helicity combinations) four-point gluon scattering amplitudes in AdS4 /CFT3 (4-D AdS and 3-D CFT) as sums of products of three-point amplitudes. And then we calculate a five-point gluon scattering amplitude in AdS4 /CFT3 by decomposing it into a sum of products of these four-point and three-point amplitudes. Finally we comment on useful identities for checking these amplitudes. This work was supported by a Weinstein Davidson College Research Initiative Summer Research grant.

  19. Complementary Barrier Infrared Detector (CBIRD) Contact Methods

    NASA Technical Reports Server (NTRS)

    Ting, David Z.; Hill, Cory J.; Gunapala, Sarath D.

    2013-01-01

    The performance of the CBIRD detector is enhanced by using new device contacting methods that have been developed. The detector structure features a narrow gap adsorber sandwiched between a pair of complementary, unipolar barriers that are, in turn, surrounded by contact layers. In this innovation, the contact adjacent to the hole barrier is doped n-type, while the contact adjacent to the electron barrier is doped p-type. The contact layers can have wider bandgaps than the adsorber layer, so long as good electrical contacts are made to them. If good electrical contacts are made to either (or both) of the barriers, then one could contact the barrier(s) directly, obviating the need for additional contact layers. Both the left and right contacts can be doped either n-type or ptype. Having an n-type contact layer next to the electron barrier creates a second p-n junction (the first being the one between the hole barrier and the adsorber) over which applied bias could drop. This reduces the voltage drop over the adsorber, thereby reducing dark current generation in the adsorber region.

  20. Salt deposition at particle contact points

    NASA Astrophysics Data System (ADS)

    Nie, Xiaodong; Evitts, Richard W.; Besant, Robert W.; Kennell, Glyn F.

    2015-09-01

    Caking may occur when granular potash fertilizer with a moisture content greater than 0.25 % (w/w) undergoes drying. Since cake strength is proportional to the mass of crystal deposited per unit volume near contact points (and other factors) the modelling of mass deposition near contact points is important. The Young-Laplace equation for the air-salt-solution interface is used to determine the geometry of a 2-D planar saline film between two cubic potash particles. A 2-D theoretical model is developed and applied for ion diffusion and deposition near the contact point during drying. The numerical predictions of ion diffusion in an initially saturated salt illustrate the transient spatial distribution of new KCl deposits along the solid surfaces near the contact line. These results indicate the average salt deposition commences at the air-liquid-solid intersection, where the liquid film is thinnest, and moves toward the particle contact point with increasing area averaged KCl deposits, causing the formation of crystal deposits and bridges near contact points. It is concluded that the average salt deposit height increases inversely with distance from the contact point and decreases with initial contact angle of the contact region, but the deposition is nearly independent of the evaporation or drying rate near each contact region. Caking strength depends on, among other parameters, the amount of salt deposition near contact points.

  1. Fingertip contact influences human postural control

    NASA Technical Reports Server (NTRS)

    Jeka, J. J.; Lackner, J. R.

    1994-01-01

    Touch and pressure stimulation of the body surface can strongly influence apparent body orientation, as well as the maintenance of upright posture during quiet stance. In the present study, we investigated the relationship between postural sway and contact forces at the fingertip while subjects touched a rigid metal bar. Subjects were tested in the tandem Romberg stance with eyes open or closed under three conditions of fingertip contact: no contact, touch contact (< 0.98 N of force), and force contact (as much force as desired). Touch contact was as effective as force contact or sight of the surroundings in reducing postural sway when compared to the no contact, eyes closed condition. Body sway and fingertip forces were essentially in phase with force contact, suggesting that fingertip contact forces are physically counteracting body sway. Time delays between body sway and fingertip forces were much larger with light touch contact, suggesting that the fingertip is providing information that allows anticipatory innervation of musculature to reduce body sway. The results are related to observations on precision grip as well as the somatosensory, proprioceptive, and motor mechanisms involved in the reduction of body sway.

  2. Contact kinematics of biomimetic scales

    SciTech Connect

    Ghosh, Ranajay; Ebrahimi, Hamid; Vaziri, Ashkan

    2014-12-08

    Dermal scales, prevalent across biological groups, considerably boost survival by providing multifunctional advantages. Here, we investigate the nonlinear mechanical effects of biomimetic scale like attachments on the behavior of an elastic substrate brought about by the contact interaction of scales in pure bending using qualitative experiments, analytical models, and detailed finite element (FE) analysis. Our results reveal the existence of three distinct kinematic phases of operation spanning linear, nonlinear, and rigid behavior driven by kinematic interactions of scales. The response of the modified elastic beam strongly depends on the size and spatial overlap of rigid scales. The nonlinearity is perceptible even in relatively small strain regime and without invoking material level complexities of either the scales or the substrate.

  3. Contact dermatitis in Alstroemeria workers.

    PubMed

    van der Mei, I A; de Boer, E M; Bruynzeel, D P

    1998-09-01

    Hand dermatitis is common in workers in the horticultural industry. This study determined the prevalence of hand dermatitis in workers of Alstroemeria cultivation, investigated how many workers had been sensitized by tulipalin A (the allergen in Alstroemeria) and took stock of a wide range of determinants of hand dermatitis. The 12-month period prevalence of major hand dermatitis amounted to 29.5% whereas 7.4% had minor dermatitis. Of these workers, 52.1% were sensitized for tulipalin A. Several personal and work-related determinants played a role in the multifactorial aetiology of hand dermatitis. Factors which showed a significant relationship with major hand dermatitis were: female sex, atopic dermatitis, chapped hands and the frequency of washing hands. It may be concluded that the Alstroemeria workers are a population at risk of developing contact dermatitis and it might be useful to carry out an educational campaign to lower the high prevalence.

  4. Interdigitated back contact solar cells

    NASA Astrophysics Data System (ADS)

    Lundstrom, M. S.; Schwartz, R. J.

    1980-08-01

    The interdigitated back contact solar cell (IBC cell) was shown to possess a number of advantages for silicon solar cells, which operate at high concentration. A detailed discussion of the factors which need to be considered in the analysis of semiconducting devices which utilize heavily doped regions such as those which are found in solar cells in both the emitter and in the back surface field regions is given. This discussion covers the questions of: how to handle degeneracy, how to compute carrier concentrations in the absence of knowledge of the details of the band structure under heavily doped conditions, and how to reconcile the usual interpretation of heavy doping as a rigid shift of the bands with the band tailing and impurity level conduction models. It also discusses the reasons for the observed discrepancies between various experimental measurements of bandgap narrowing.

  5. Contact process with temporal disorder.

    PubMed

    Barghathi, Hatem; Vojta, Thomas; Hoyos, José A

    2016-08-01

    We investigate the influence of time-varying environmental noise, i.e., temporal disorder, on the nonequilibrium phase transition of the contact process. Combining a real-time renormalization group, scaling theory, and large scale Monte-Carlo simulations in one and two dimensions, we show that the temporal disorder gives rise to an exotic critical point. At criticality, the effective noise amplitude diverges with increasing time scale, and the probability distribution of the density becomes infinitely broad, even on a logarithmic scale. Moreover, the average density and survival probability decay only logarithmically with time. This infinite-noise critical behavior can be understood as the temporal counterpart of infinite-randomness critical behavior in spatially disordered systems, but with exchanged roles of space and time. We also analyze the generality of our results, and we discuss potential experiments.

  6. Contact process with temporal disorder

    NASA Astrophysics Data System (ADS)

    Barghathi, Hatem; Vojta, Thomas; Hoyos, José A.

    2016-08-01

    We investigate the influence of time-varying environmental noise, i.e., temporal disorder, on the nonequilibrium phase transition of the contact process. Combining a real-time renormalization group, scaling theory, and large scale Monte-Carlo simulations in one and two dimensions, we show that the temporal disorder gives rise to an exotic critical point. At criticality, the effective noise amplitude diverges with increasing time scale, and the probability distribution of the density becomes infinitely broad, even on a logarithmic scale. Moreover, the average density and survival probability decay only logarithmically with time. This infinite-noise critical behavior can be understood as the temporal counterpart of infinite-randomness critical behavior in spatially disordered systems, but with exchanged roles of space and time. We also analyze the generality of our results, and we discuss potential experiments.

  7. Single-contact tunneling thermometry

    DOEpatents

    Maksymovych, Petro

    2016-02-23

    A single-contact tunneling thermometry circuit includes a tunnel junction formed between two objects. Junction temperature gradient information is determined based on a mathematical relationship between a target alternating voltage applied across the junction and the junction temperature gradient. Total voltage measured across the junction indicates the magnitude of the target alternating voltage. A thermal gradient is induced across the junction. A reference thermovoltage is measured when zero alternating voltage is applied across the junction. An increasing alternating voltage is applied while measuring a thermovoltage component and a DC rectification voltage component created by the applied alternating voltage. The target alternating voltage is reached when the thermovoltage is nullified or doubled by the DC rectification voltage depending on the sign of the reference thermovoltage. Thermoelectric current and current measurements may be utilized in place of the thermovoltage and voltage measurements. The system may be automated with a feedback loop.

  8. International rigid contact lens prescribing.

    PubMed

    Efron, Nathan; Morgan, Philip B; Helland, Magne; Itoi, Motozumi; Jones, Deborah; Nichols, Jason J; van der Worp, Eef; Woods, Craig A

    2010-06-01

    Rigid lenses have been fitted less since the introduction of soft lenses nearly 40 years ago. Data that we have gathered from annual contact lens fitting surveys conducted in Australia, Canada, Japan, the Netherlands, Norway, the UK and the USA between 2000 and 2008 facilitate an accurate characterization of the pattern of the decline of rigid lens fitting during the first decade of this century. There is a trend for rigid lenses to be utilized primarily for refitting those patients who are already successful rigid lens wearers-most typically older females being refit with higher Dk materials. Rigid lenses are generally fitted on a full-time basis (four or more days of wear per week) without a planned replacement schedule. Orthokeratology is especially popular in the Netherlands, but is seldom prescribed in the other countries surveyed.

  9. 75 FR 6032 - National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-05

    ... ADMINISTRATION National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation... renewal of a previously approved information collection requirement regarding the National Contact Center... 20405. Please cite OMB Control No. 3090-0278, National Contact Center Customer Evaluation Survey, in...

  10. Contact resistance at planar metal contacts on bilayer graphene and effects of molecular insertion layers.

    PubMed

    Nouchi, Ryo

    2017-03-01

    The possible origins of metal-bilayer graphene (BLG) contact resistance are investigated by taking into consideration the bandgap formed by interfacial charge transfer at the metal contacts. Our results show that a charge injection barrier (Schottky barrier) does not contribute to the contact resistance because the BLG under the contacts is always degenerately doped. We also showed that the contact-doping-induced increase in the density of states (DOS) of BLG under the metal contacts decreases the contact resistance owing to enhanced charge carrier tunnelling at the contacts. The contact doping can be enhanced by inserting molecular dopant layers into the metal contacts. However, carrier tunnelling through the insertion layer increases the contact resistance, and thus, alternative device structures should be employed. Finally, we showed that the inter-band transport by variable range hopping via in-gap states is the largest contributor to contact resistance when the carrier type of the gated channel is opposite to the contact doping carrier type. This indicates that the strategy of contact resistance reduction by the contact-doping-induced increase in the DOS is effective only for a single channel transport branch (n- or p-type) depending on the contact doping carrier type.

  11. A 3D contact analysis approach for the visualization of the electrical contact asperities

    PubMed Central

    Swingler, Jonathan

    2017-01-01

    The electrical contact is an important phenomenon that should be given into consideration to achieve better performance and long term reliability for the design of devices. Based upon this importance, the electrical contact interface has been visualized as a ‘‘3D Contact Map’’ and used in order to investigate the contact asperities. The contact asperities describe the structures above and below the contact spots (the contact spots define the 3D contact map) to the two conductors which make the contact system. The contact asperities require the discretization of the 3D microstructures of the contact system into voxels. A contact analysis approach has been developed and introduced in this paper which shows the way to the 3D visualization of the contact asperities of a given contact system. For the discretization of 3D microstructure of contact system into voxels, X-ray Computed Tomography (CT) method is used in order to collect the data of a 250 V, 16 A rated AC single pole rocker switch which is used as a contact system for investigation. PMID:28105383

  12. Contact resistance at planar metal contacts on bilayer graphene and effects of molecular insertion layers

    NASA Astrophysics Data System (ADS)

    Nouchi, Ryo

    2017-03-01

    The possible origins of metal–bilayer graphene (BLG) contact resistance are investigated by taking into consideration the bandgap formed by interfacial charge transfer at the metal contacts. Our results show that a charge injection barrier (Schottky barrier) does not contribute to the contact resistance because the BLG under the contacts is always degenerately doped. We also showed that the contact-doping-induced increase in the density of states (DOS) of BLG under the metal contacts decreases the contact resistance owing to enhanced charge carrier tunnelling at the contacts. The contact doping can be enhanced by inserting molecular dopant layers into the metal contacts. However, carrier tunnelling through the insertion layer increases the contact resistance, and thus, alternative device structures should be employed. Finally, we showed that the inter-band transport by variable range hopping via in-gap states is the largest contributor to contact resistance when the carrier type of the gated channel is opposite to the contact doping carrier type. This indicates that the strategy of contact resistance reduction by the contact-doping-induced increase in the DOS is effective only for a single channel transport branch (n- or p-type) depending on the contact doping carrier type.

  13. Brick walls and AdS/CFT

    NASA Astrophysics Data System (ADS)

    Kay, Bernard S.; Ortíz, L.

    2014-05-01

    We discuss the relationship between the bulk-boundary correspondence in Rehren's algebraic holography (and in other `fixed-background', QFT-based, approaches to holography) and in mainstream string-theoretic `Maldacena AdS/CFT'. Especially, we contrast the understanding of black-hole entropy from the point of view of QFT in curved spacetime—in the framework of 't Hooft's `brick wall' model—with the understanding based on Maldacena AdS/CFT. We show that the brick-wall modification of a Klein-Gordon field in the Hartle-Hawking-Israel state on dimensional Schwarzschild AdS has a well-defined boundary limit with the same temperature and entropy as the brick-wall-modified bulk theory. One of our main purposes is to point out a close connection, for general AdS/CFT situations, between the puzzle raised by Arnsdorf and Smolin regarding the relationship between Rehren's algebraic holography and mainstream AdS/CFT and the puzzle embodied in the `complementarity principle' proposed by Mukohyama and Israel in their work on the brick-wall approach to black hole entropy. Working on the assumption that similar results will hold for bulk QFT other than the Klein-Gordon field and for Schwarzschild AdS in other dimensions, and recalling the first author's proposed resolution to the Mukohyama-Israel puzzle based on his `matter-gravity entanglement hypothesis', we argue that, in Maldacena AdS/CFT, the algebra of the boundary CFT is isomorphic only to a proper subalgebra of the bulk algebra, albeit (at non-zero temperature) the (GNS) Hilbert spaces of bulk and boundary theories are still the `same'—the total bulk state being pure, while the boundary state is mixed (thermal). We also argue from the finiteness of its boundary (and hence, on our assumptions, also bulk) entropy at finite temperature, that the Rehren dual of the Maldacena boundary CFT cannot itself be a QFT and must, instead, presumably be something like a string theory.

  14. Contact angle hysteresis of microbead suspensions.

    PubMed

    Waghmare, Prashant R; Mitra, Sushanta K

    2010-11-16

    Microbead suspensions are often used in microfluidic devices for transporting biomolecules. An experimental investigation on the wettability of microbead suspension is presented in this study. The variation in the surface tension and the equilibrium contact angle with the change in the volume fraction of the microbead is presented here. The surface tension of the microbead suspension is measured with the pendant drop technique, whereas the dynamic contact angle measurements, i.e., advancing and receding contact angles, are measured with the sessile drop technique. An equilibrium contact angle of a suspension with particular volume fraction is determined by computing an average over the measured advancing and receding contact angles. It is observed that the surface tension and the equilibrium contact angle determined from advancing and receding contact angles vary with the magnitude of the microbeads volume fraction in the suspension. A decrease in the surface tension with an increase in the volume fraction of the microbead suspension is observed. The advancement and the recession in contact line for dynamic contact angle measurements are achieved with the motorized dosing mechanism. For microbead suspensions, the advancement of the contact line is faster as compared to the recession of the contact line for the same flow rate. The presence of microbeads assists in the advancement and the recession of the contact line of the suspension. A decrease in the equilibrium contact angles with an increase in the microbead suspension volume fraction is observed. Inclusion of microbeads in the suspension increases the wetting capability for the considered combination of the microbead suspension and substrate. Finally, empirical correlations for the surface tension and the contact angle of the suspension as a function of microbead volume fraction are proposed. Such correlations can readily be used to develop mechanistic models for the capillary transport of microbead

  15. Finite Element Modeling of a Cylindrical Contact Using Hertzian Assumptions

    NASA Technical Reports Server (NTRS)

    Knudsen, Erik

    2003-01-01

    The turbine blades in the high-pressure fuel turbopump/alternate turbopump (HPFTP/AT) are subjected to hot gases rapidly flowing around them. This flow excites vibrations in the blades. Naturally, one has to worry about resonance, so a damping device was added to dissipate some energy from the system. The foundation is now laid for a very complex problem. The damper is in contact with the blade, so now there are contact stresses (both normal and tangential) to contend with. Since these stresses can be very high, it is not all that difficult to yield the material. Friction is another non-linearity and the blade is made out of a Nickel-based single-crystal superalloy that is orthotropic. A few approaches exist to solve such a problem and computer models, using contact elements, have been built with friction, plasticity, etc. These models are quite cumbersome and require many hours to solve just one load case and material orientation. A simpler approach is required. Ideally, the model should be simplified so the analysis can be conducted faster. When working with contact problems determining the contact patch and the stresses in the material are the main concerns. Closed-form solutions for non-conforming bodies, developed by Hertz, made out of isotropic materials are readily available. More involved solutions for 3-D cases using different materials are also available. The question is this: can Hertzian1 solutions be applied, or superimposed, to more complicated problems-like those involving anisotropic materials? That is the point of the investigation here. If these results agree with the more complicated computer models, then the analytical solutions can be used in lieu of the numerical solutions that take a very long time to process. As time goes on, the analytical solution will eventually have to include things like friction and plasticity. The models in this report use no contact elements and are essentially an applied load problem using Hertzian assumptions to

  16. Photon gas thermodynamics in dS and AdS momentum spaces

    NASA Astrophysics Data System (ADS)

    Gorji, M. A.; Hosseinzadeh, V.; Nozari, K.; Vakili, B.

    2016-07-01

    In this paper, we study thermostatistical properties of a photon gas in the framework of two deformed special relativity models defined by the cosmological coordinatizations of the de Sitter (dS) and anti-de Sitter (AdS) momentum spaces. The dS model is a doubly special relativity theory in which an ultraviolet length scale is invariant under the deformed Lorentz transformations. For the case of the AdS model, however, the Lorentz symmetry breaks at the high energy regime. We show that the existence of a maximal momentum in dS momentum space leads to maximal pressure and temperature at the thermodynamical level, while maximal internal energy and entropy arise for the case of the AdS momentum space due to the existence of a maximal kinematical energy. These results show that the thermodynamical duality of these models is very similar to their well-known kinematical duality.

  17. Black hole microstates in AdS4 from supersymmetric localization

    NASA Astrophysics Data System (ADS)

    Benini, Francesco; Hristov, Kiril; Zaffaroni, Alberto

    2016-05-01

    This paper addresses a long standing problem, the counting of the microstates of supersymmetric asymptotically AdS black holes in terms of a holographically dual field theory. We focus on a class of asymptotically AdS4 static black holes preserving two real supercharges which are dual to a topologically twisted deformation of the ABJM theory. We evaluate in the large N limit the topologically twisted index of the ABJM theory and we show that it correctly reproduces the entropy of the AdS4 black holes. An extremization of the index with respect to a set of chemical potentials is required. We interpret it as the selection of the exact R-symmetry of the superconformal quantum mechanics describing the horizon of the black hole.

  18. A note on vectorial AdS5/CFT4 duality for spin- j boundary theory

    NASA Astrophysics Data System (ADS)

    Bae, Jin-Beom; Joung, Euihun; Lal, Shailesh

    2016-12-01

    The vectorial holographic correspondences between higher-spin theories in AdS5 and free vector models on the boundary are extended to the cases where the latter is described by free massless spin- j field. The dual higher-spin theory in the bulk does not include gravity and can only be defined on rigid AdS5 background with S 4 boundary. We discuss various properties of these rather special higher-spin theories and calculate their one-loop free energies. We show that the result is proportional to the same quantity for spin- j doubleton treated as if it is a AdS5 field. Finally, we consider even more special case where the boundary theory itself is given by an infinite tower of massless higher-spin fields.

  19. QCD Condensates and Holographic Wilson Loops for Asymptotically AdS Spaces

    SciTech Connect

    Quevedo, R. Carcasses; Goity, Jose L.; Trinchero, Roberto C.

    2014-02-01

    The minimization of the Nambu-Goto (NG) action for a surface whose contour defines a circular Wilson loop of radius a placed at a finite value of the coordinate orthogonal to the border is considered. This is done for asymptotically AdS spaces. The condensates of dimension n = 2, 4, 6, 8, and 10 are calculated in terms of the coefficients in the expansion in powers of the radius a of the on-shell subtracted NG action for small a->0. The subtraction employed is such that it presents no conflict with conformal invariance in the AdS case and need not introduce an additional infrared scale for the case of confining geometries. It is shown that the UV value of the gluon condensates is universal in the sense that it only depends on the first coefficients of the difference with the AdS case.

  20. Stability of warped AdS3 vacua of topologically massive gravity

    NASA Astrophysics Data System (ADS)

    Anninos, Dionysios; Esole, Mboyo; Guica, Monica

    2009-10-01

    AdS3 vacua of topologically massive gravity (TMG) have been shown to be perturbatively unstable for all values of the coupling constant except the chiral point μl = 1. We study the possibility that the warped vacua of TMG, which exist for all values of μ, are stable under linearized perturbations. In this paper, we show that spacelike warped AdS3 vacua with Compère-Detournay boundary conditions are indeed stable in the range μl>3. This is precisely the range in which black hole solutions arise as discrete identifications of the warped AdS3 vacuum. The situation somewhat resembles chiral gravity: although negative energy modes do exist, they are all excluded by the boundary conditions, and the perturbative spectrum solely consists of boundary (pure large gauge) gravitons.

  1. High Transmembrane Voltage Raised by Close Contact Initiates Fusion Pore.

    PubMed

    Bu, Bing; Tian, Zhiqi; Li, Dechang; Ji, Baohua

    2016-01-01

    Membrane fusion lies at the heart of neuronal communication but the detailed mechanism of a critical step, fusion pore initiation, remains poorly understood. Here, through atomistic molecular dynamics simulations, a transient pore formation induced by a close contact of two apposed bilayers is firstly reported. Such a close contact gives rise to a high local transmembrane voltage that induces the transient pore formation. Through simulations on two apposed bilayers fixed at a series of given distances, the process in which two bilayers approaching to each other under the pulling force from fusion proteins for membrane fusion was mimicked. Of note, this close contact induced fusion pore formation is contrasted with previous reported electroporation under ad hoc applied external electric field or ionic charge in-balance. We show that the transmembrane voltage increases with the decrease of the distance between the bilayers. Below a critical distance, depending on the lipid composition, the local transmembrane voltage can be sufficiently high to induce the transient pores. The size of these pores is approximately 1~2 nm in diameter, which is large enough to allow passing of neurotransmitters. A resealing of the membrane pores resulting from the neutralization of the transmembrane voltage by ions through the pores was then observed. We also found that the membrane tension can either prolong the lifetime of transient pores or cause them to dilate for full collapse. This result provides a possible mechanism for fusion pore formation and regulation of pathway of fusion process.

  2. High Transmembrane Voltage Raised by Close Contact Initiates Fusion Pore

    PubMed Central

    Bu, Bing; Tian, Zhiqi; Li, Dechang; Ji, Baohua

    2016-01-01

    Membrane fusion lies at the heart of neuronal communication but the detailed mechanism of a critical step, fusion pore initiation, remains poorly understood. Here, through atomistic molecular dynamics simulations, a transient pore formation induced by a close contact of two apposed bilayers is firstly reported. Such a close contact gives rise to a high local transmembrane voltage that induces the transient pore formation. Through simulations on two apposed bilayers fixed at a series of given distances, the process in which two bilayers approaching to each other under the pulling force from fusion proteins for membrane fusion was mimicked. Of note, this close contact induced fusion pore formation is contrasted with previous reported electroporation under ad hoc applied external electric field or ionic charge in-balance. We show that the transmembrane voltage increases with the decrease of the distance between the bilayers. Below a critical distance, depending on the lipid composition, the local transmembrane voltage can be sufficiently high to induce the transient pores. The size of these pores is approximately 1~2 nm in diameter, which is large enough to allow passing of neurotransmitters. A resealing of the membrane pores resulting from the neutralization of the transmembrane voltage by ions through the pores was then observed. We also found that the membrane tension can either prolong the lifetime of transient pores or cause them to dilate for full collapse. This result provides a possible mechanism for fusion pore formation and regulation of pathway of fusion process. PMID:28018169

  3. 21 CFR 186.1 - Substances added indirectly to human food affirmed as generally recognized as safe (GRAS).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... of food-contact surface(s), the functional use(s) of the ingredient, and the level(s) of use. Any use... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Substances added indirectly to human food affirmed as generally recognized as safe (GRAS). 186.1 Section 186.1 Food and Drugs FOOD AND...

  4. Towards an optimal contact metal for CNTFETs

    NASA Astrophysics Data System (ADS)

    Fediai, Artem; Ryndyk, Dmitry A.; Seifert, Gotthard; Mothes, Sven; Claus, Martin; Schröter, Michael; Cuniberti, Gianaurelio

    2016-05-01

    Downscaling of the contact length Lc of a side-contacted carbon nanotube field-effect transistor (CNTFET) is challenging because of the rapidly increasing contact resistance as Lc falls below 20-50 nm. If in agreement with existing experimental results, theoretical work might answer the question, which metals yield the lowest CNT-metal contact resistance and what physical mechanisms govern the geometry dependence of the contact resistance. However, at the scale of 10 nm, parameter-free models of electron transport become computationally prohibitively expensive. In our work we used a dedicated combination of the Green function formalism and density functional theory to perform an overall ab initio simulation of extended CNT-metal contacts of an arbitrary length (including infinite), a previously not achievable level of simulations. We provide a systematic and comprehensive discussion of metal-CNT contact properties as a function of the metal type and the contact length. We have found and been able to explain very uncommon relations between chemical, physical and electrical properties observed in CNT-metal contacts. The calculated electrical characteristics are in reasonable quantitative agreement and exhibit similar trends as the latest experimental data in terms of: (i) contact resistance for Lc = ∞, (ii) scaling of contact resistance Rc(Lc); (iii) metal-defined polarity of a CNTFET. Our results can guide technology development and contact material selection for downscaling the length of side-contacts below 10 nm.Downscaling of the contact length Lc of a side-contacted carbon nanotube field-effect transistor (CNTFET) is challenging because of the rapidly increasing contact resistance as Lc falls below 20-50 nm. If in agreement with existing experimental results, theoretical work might answer the question, which metals yield the lowest CNT-metal contact resistance and what physical mechanisms govern the geometry dependence of the contact resistance. However, at

  5. The generalization of charged AdS black hole specific volume and number density

    NASA Astrophysics Data System (ADS)

    Wang, Zi-Liang; He, Miao; Fang, Chao; Sun, Dao-Quan; Deng, Jian-Bo

    2017-04-01

    In this paper, by proposing a generalized specific volume, we restudy the P- V criticality of charged AdS black holes in the extended phase space. The results show that most of the previous conclusions can be generalized without change, but the ratio {\\tilde{ρ }}_c should be 3 {\\tilde{α }}/16 in general case. Further research on the thermodynamical phase transition of black hole leads us to a natural interpretation of our assumption, and more black hole properties can be generalized. Finally, we study the number density for charged AdS black hole in higher dimensions, the results show the necessity of our assumption.

  6. Warped AdS3 , dS3 , and flows from N =(0 ,2 ) SCFTs

    NASA Astrophysics Data System (ADS)

    O'Colgáin, Eoin

    2015-05-01

    We present the general form of all timelike supersymmetric solutions to three-dimensional U (1 )3 gauged supergravity, a known consistent truncation of string theory. We uncover a rich vacuum structure, including an infinite class of new timelike-warped AdS3 (Gödel) and timelike-warped dS3 critical points. We outline the construction of supersymmetric flows, driven by irrelevant scalar operators in the SCFT, which interpolate between critical points. For flows from AdS3 to Gödel, the natural candidate for the central charge decreases along the flow. Flows to timelike-warped dS3 exhibit topology change.

  7. The Status of AdS/QCD

    SciTech Connect

    Reece, Matthew

    2011-05-23

    In this talk I give a brief assessment of the 'AdS/QCD correspondence', its successes, and its failures. I begin with a review of the AdS/CFT correspondence, with an emphasis on why the large N, large 't Hooft coupling limit is necessary for a calculable theory. I then briefly discuss attempts to extrapolate this correspondence to QCD-like theories, stressing why the failure of the large 't Hooft coupling limit is more important than the breakdown of the large N expansion. I sketch how event shapes can manifest stringy physics, and close with some brief remarks on the prospects for future improvements.

  8. Advanced Optical A/D Converter

    DTIC Science & Technology

    1993-05-01

    before the receiver and separately by reducing the gain in the EDFA . It is important to note that the optical power level was varied while all the...could not exceed roughly 50% of the maximum power available at full gain from the EDFA . 4.2 Baseband-Mode Testing The single-channel system was also...AD-A275 663 Advanced Optical A/D Convert M.C. Hamilton, J.A. Bell, D.A. Leep, J.P. Lin The Boeing Company Boeing Defense and Space Group P.O. Box

  9. Dynamic contact angle measurements on superhydrophobic surfaces

    NASA Astrophysics Data System (ADS)

    Kim, Jeong-Hyun; Kavehpour, H. Pirouz; Rothstein, Jonathan P.

    2015-03-01

    In this paper, the dynamic advancing and receding contact angles of a series of aqueous solutions were measured on a number of hydrophobic and superhydrophobic surfaces using a modified Wilhelmy plate technique. Superhydrophobic surfaces are hydrophobic surfaces with micron or nanometer sized surface roughness. These surfaces have very large static advancing contact angles and little static contact angle hysteresis. In this study, the dynamic advancing and dynamic receding contact angles on superhydrophobic surfaces were measured as a function of plate velocity and capillary number. The dynamic contact angles measured on a smooth hydrophobic Teflon surface were found to obey the scaling with capillary number predicted by the Cox-Voinov-Tanner law, θD3 ∝ Ca. The response of the dynamic contact angle on the superhydrophobic surfaces, however, did not follow the same scaling law. The advancing contact angle was found to remain constant at θA = 160∘, independent of capillary number. The dynamic receding contact angle measurements on superhydrophobic surfaces were found to decrease with increasing capillary number; however, the presence of slip on the superhydrophobic surface was found to result in a shift in the onset of dynamic contact angle variation to larger capillary numbers. In addition, a much weaker dependence of the dynamic contact angle on capillary number was observed for some of the superhydrophobic surfaces tested.

  10. The role of molecular epidemiology in contact investigations: a US perspective.

    PubMed

    Daley, C L; Kawamura, L M

    2003-12-01

    Preventing tuberculosis (TB) transmission through treatment of active cases and contact investigation is the highest priority of TB control programs in the United States. The role of contact investigation is becoming increasingly important as the number of TB cases declines nationally. However, the effectiveness of contact investigation has been difficult to assess because, prior to the availability of molecular genotyping techniques, levels of transmission were crudely measurable. Epidemiological links within and outside the traditional concentric circle approach are limited by the quality of the contact investigation, the skill and knowledge of the investigator and the information provided by the patient. Molecular epidemiology has added a new dimension by enabling the recognition of unsuspected transmission, likely locations of transmission, and quantification of the extent of transmission that is occurring within a given population. In the future, as real-time genotyping becomes more available, the role of molecular epidemiology is likely to expand.

  11. Tear analysis in contact lens wearers.

    PubMed Central

    Farris, R L

    1985-01-01

    Tear analysis in contact lens wearers was compared with tear analysis in aphakics without contact lens wear and normal phakic patients. Subjects were divided into five groups: group 1, aphakic without contact lens; group 2, phakic with daily-wear hard contact lens; group 3, phakic with daily-wear soft contact lens; group 4, phakic with extended-wear soft contact lens; and group 5, aphakic with extended-wear soft contact lens. The experimental groups were compared with age- and sex-matched control groups for statistical analysis of tear variables by means of the Student's t-test. The variables measured were tear osmolarity, tear albumin, and lysozyme and lactoferrin concentrations in basal and reflex tears. Highly significant elevations of tear osmolarity were found in aphakic subjects without contact lenses. Less significant differences in tear osmolarity were found in phakic subjects with hard daily-wear lenses or with extended-wear soft lenses. Tear albumin, lysozyme, and lactoferrin in basal and reflex tears were not significantly different in the different groups of contact lens wearers or in the group of aphakic subjects without contact lenses compared with their control groups. Individual variations in tear albumin, lysozyme, and lactoferrin appeared to be responsible for the inability to demonstrate significant differences in tear composition in association with the wearing of different types of contact lenses. Older and aphakic patients demonstrated a tendency to have increased concentrations of proteins in the tears compared with younger, phakic contact lens wearers and normal controls without contact lenses. PMID:3914131

  12. Chronic mouse model of TMA-induced contact hypersensitivity.

    PubMed

    Schneider, Claudia; Döcke, Wolf-Dietrich F; Zollner, Thomas M; Röse, Lars

    2009-04-01

    Due to the steadily increasing incidence of atopic dermatitis (AD), especially in children, there is a high medical need for new therapies and improved animal models. In mice, trimellitic anhydride (TMA) is routinely used to trigger T-cell-dependent contact hypersensitivity (CHS) reactions. In this study, we compared the standard acute TMA-induced CHS in Balb/c mice with subacute and chronic models of TMA-induced ear inflammation. Compared to the acute model, the chronic CHS model more closely reflects characteristics of AD, such as typical morphological changes of the inflamed skin, strong infiltration with T cells, major histocompatibility complex II-positive cells, eosinophils, and mast cells, a T-helper cell-type (Th) 2 cytokine profile and a strong increase of serum IgE levels. Moreover, a strong lymph node involvement with T-helper cell dominance and a mixed Th1/Th2 T-cell differentiation and activation pattern was demonstrated. Importantly, as demonstrated by successful therapy with prednisolone, the chronic TMA-induced CHS model, in contrast to acute and subacute models, made prolonged therapeutic treatment of a pre-established skin inflammation possible. Altogether, we present an improved model of mouse T-cell-dependent skin inflammation for AD. We hope this model will enhance the predictive value of animal models for therapeutic treatment of atopic eczema.

  13. Stochastic Resonance in Time-to-Contact Judgments

    NASA Astrophysics Data System (ADS)

    Ranjit, Manish; Gazula, Harshvardhan; Hsiang, Simon M.; Delucia, Patricia R.

    2015-04-01

    Stochastic resonance (SR) is a counterintuitive phenomenon in which additive noise enhances performance of a nonlinear system. Previous studies demonstrated SR effect on human tactile sensitivity by adding noise of same modality and cross modality. Similarly, enhancement of human hearing through additive noise has been studied. In this study, we investigate the effect of noise in visual perception, specifically time-to-contact (TTC) judgments. This study explores four research questions: (1) Does noise help in TTC judgments? (2) How does noise affect speed and accuracy of TTC judgments? (3) Does cross modal noise help in TTC judgments? (4) How does cross modal noise affect speed and accuracy of TTC judgments? Through simulation, we show that noise in optical cue can enhance weak signals. We also demonstrate that noise can improve speed of TTC judgments at the expense of accuracy. Similarly, we demonstrate SR by adding noise of cross modality. These findings provide plausible hypotheses regarding how much noise should be added to enhance TTC judgments.

  14. Contact angle measurement on rough surfaces.

    PubMed

    Meiron, Tammar S; Marmur, Abraham; Saguy, I Sam

    2004-06-15

    A new method for the measurement of apparent contact angles at the global energy minimum on real surfaces has been developed. The method consists of vibrating the surface, taking top-view pictures of the drop, monitoring the drop roundness, and calculating the contact angle from the drop diameter and weight. The use of the new method has been demonstrated for various rough surfaces, all having the same surface chemistry. In order to establish the optimal vibration conditions, the proper ranges for the system parameters (i.e., drop volume, vibration time, frequency of vibration, and amplitude of vibration) were determined. The reliability of the method has been demonstrated by the fact that the ideal contact angles of all surfaces, as calculated from the Wenzel equation using the measured apparent contact angles, came out to be practically identical. This ideal contact angle has been compared with three methods of calculation from values of advancing and receding contact angles.

  15. Contact Dermatitis for the Practicing Allergist.

    PubMed

    Bernstein, David I

    2015-01-01

    This article provides an overview of important practice recommendations from the recently updated Contact Dermatitis Practice Parameter. This updated parameter provides essential recommendations pertaining to clinical history, physical examination, and patch testing evaluation of patients suspected of allergic contact dermatitis. In addition to providing guidance for performing and interpreting closed patch testing, the updated parameter provides concrete recommendations for assessing metal hypersensitivity in patients receiving prosthetic devices, for evaluating workers with occupational contact dermatitis, and also for addressing allergic contact dermatitis in children. Finally, the document provides practical recommendations useful for educating patients regarding avoidance of exposure to known contact sensitizers in the home and at work. The Contact Dermatitis Parameter is designed as a practical, evidence-based clinical tool to be used by allergists and dermatologists who routinely are called upon to evaluate patients with skin disorders.

  16. The AD Nurse: Prepared to be Prepared

    ERIC Educational Resources Information Center

    Beverly, Lynne; Junker, Mary H.

    1977-01-01

    It is not enough for the new associate degree (AD) nursing graduate to know the theory and be willing to learn. She must also have some skill in providing basic nursing care. Examples of applicants, both ADNs and BSNs, are described to illustrate the nursing talent necessary to practice sensitively and effectively. (Editor/TA)

  17. Value-Added Analysis in Instruction

    ERIC Educational Resources Information Center

    Nicholson, Michael R.; Brown, Jeffrey R.

    2010-01-01

    Value-added data provide a viable alternative for gauging school effectiveness--one virtually free of the confounding effects of student demographics and other factors relating to student learning. How is it different from other measuring methods? It concentrates on growth, rather than attainment. This strengthens the concept and measurement of…

  18. Adding calcium improves lithium ferrite core

    NASA Technical Reports Server (NTRS)

    Lessoff, H.

    1969-01-01

    Adding calcium increases uniformity of grain growth over a wide range of sintering temperatures and reduces porosity within the grain. Ferrite cores containing calcium have square hysteresis loops and high curie temperatures, making them useful in coincident current memories of digital electronic computers.

  19. Higher Education Value Added Using Multiple Outcomes

    ERIC Educational Resources Information Center

    Milla, Joniada; Martín, Ernesto San; Van Bellegem, Sébastien

    2016-01-01

    In this article we develop a methodology for the joint value added analysis of multiple outcomes that takes into account the inherent correlation between them. This is especially crucial in the analysis of higher education institutions. We use a unique Colombian database on universities, which contains scores in five domains tested in a…

  20. Adding Users to the Website Design Process

    ERIC Educational Resources Information Center

    Tomeo, Megan L.

    2012-01-01

    Alden Library began redesigning its website over a year ago. Throughout the redesign process the students, faculty, and staff that make up the user base were added to the conversation by utilizing several usability test methods. This article focuses on the usability testing conducted at Alden Library and delves into future usability testing, which…

  1. Drag force in AdS/CFT

    SciTech Connect

    Gubser, Steven S.

    2006-12-15

    The AdS/CFT correspondence and a classical test string approximation are used to calculate the drag force on an external quark moving in a thermal plasma of N=4 super-Yang-Mills theory. This computation is motivated by the phenomenon of jet-quenching in relativistic heavy ion collisions.

  2. Value Added School Review Field Guide

    ERIC Educational Resources Information Center

    Alberta Education, 2009

    2009-01-01

    The "Value-Added School Review (VSR)" is an analytical model designed to assist schools in identifying and addressing opportunities for school improvement. The model works best when it is focused purposefully on students and the student learning outcomes as defined in the "Guide to Education". It complements the processes…

  3. "Value Added" Proves Beneficial to Teacher Prep

    ERIC Educational Resources Information Center

    Sawchuk, Stephen

    2012-01-01

    The use of "value added" information appears poised to expand into the nation's teacher colleges, with more than a dozen states planning to use the technique to analyze how graduates of training programs fare in classrooms. Supporters say the data could help determine which teacher education pathways produce teachers who are at least as…

  4. Imago Mundi, Imago AD, Imago ADNI

    PubMed Central

    2014-01-01

    Since the launch in 2003 of the Alzheimer’s Disease Neuroimaging Initiative (ADNI) in the USA, ever growing, similarly oriented consortia have been organized and assembled around the world. The various accomplishments of ADNI have contributed substantially to a better understanding of the underlying physiopathology of aging and Alzheimer’s disease (AD). These accomplishments are basically predicated in the trinity of multimodality, standardization and sharing. This multimodality approach can now better identify those subjects with AD-specific traits that are more likely to present cognitive decline in the near future and that might represent the best candidates for smaller but more efficient therapeutic trials – trials that, through gained and shared knowledge, can be more focused on a specific target or a specific stage of the disease process. In summary, data generated from ADNI have helped elucidate some of the pathophysiological mechanisms underpinning aging and AD pathology, while contributing to the international effort in setting the groundwork for biomarker discovery and establishing standards for early diagnosis of AD. PMID:25478022

  5. Making Schools Ad-Free Zones.

    ERIC Educational Resources Information Center

    Karpatkin, Rhoda H.; Holmes, Anita

    1995-01-01

    Advertisers spend billions to market so-called educational products, services, and viewpoints to vulnerable young consumers. Budget constraints are forcing educators to accept ads and promotional materials. Several education and consumer-interest groups are developing guidelines for using commercial materials in schools. Consumers Union developed…

  6. Cutting Budget Corners While Adding Value.

    ERIC Educational Resources Information Center

    Veile, Craig N.; Carpenter, Mark J.

    2000-01-01

    Discusses how one school district saved money while adding long- term value to its capital improvement project. Planning issues involving square footage requirements, quality of material to be used, and heating and cooling system selection are discussed as are concepts to increase student learning capacity for the same construction dollars. (GR)

  7. Test Scaling and Value-Added Measurement

    ERIC Educational Resources Information Center

    Ballou, Dale

    2009-01-01

    Conventional value-added assessment requires that achievement be reported on an interval scale. While many metrics do not have this property, application of item response theory (IRT) is said to produce interval scales. However, it is difficult to confirm that the requisite conditions are met. Even when they are, the properties of the data that…

  8. Distribution of Information in Ad Hoc Networks

    DTIC Science & Technology

    2007-09-01

    INTENTIONALLY LEFT BLANK v ABSTRACT Ad-hoc networks are distributed, self-organized networks which do not need a fixed infrastructure. Entities in...73 V . CONCLUSIONS AND FUTURE WORK ............................75 A. OVERVIEW ..........................................75 B. CONCLUSIONS...statistical analysis on the results. Finally, Chapter V concludes the research and provides suggestions for further research. 7 II. BACKGROUND A

  9. "Value Added" Gauge of Teaching Probed

    ERIC Educational Resources Information Center

    Viadero, Debra

    2009-01-01

    A new study by a public and labor economist suggests that "value added" methods for determining the effectiveness of classroom teachers are built on some shaky assumptions and may be misleading. The study, due to be published in February in the "Quarterly Journal of Economics," is the first of a handful of papers now in the…

  10. Anomaly Detection Techniques for Ad Hoc Networks

    ERIC Educational Resources Information Center

    Cai, Chaoli

    2009-01-01

    Anomaly detection is an important and indispensable aspect of any computer security mechanism. Ad hoc and mobile networks consist of a number of peer mobile nodes that are capable of communicating with each other absent a fixed infrastructure. Arbitrary node movements and lack of centralized control make them vulnerable to a wide variety of…

  11. Adding Test Generation to the Teaching Machine

    ERIC Educational Resources Information Center

    Bruce-Lockhart, Michael; Norvell, Theodore; Crescenzi, Pierluigi

    2009-01-01

    We propose an extension of the Teaching Machine project, called Quiz Generator, that allows instructors to produce assessment quizzes in the field of algorithm and data structures quite easily. This extension makes use of visualization techniques and is based on new features of the Teaching Machine that allow third-party visualizers to be added as…

  12. Technology Transfer: A Contact Sport

    NASA Technical Reports Server (NTRS)

    Paynter, Nina P.

    1995-01-01

    Technology transfer is a dynamic process, involving dynamic people as the bridge between NASA Langley Research Center and the outside world. This bridge, for nonaerospace applications, is known as the Technology Applications Group. The introduction of new innovations and expertise where they are needed occurs through a 'push' and 'pull' process. A 'push' occurs when a new technology is first developed with high commercial potential and then a company is found to licence or further develop the technology. The 'pull' process occurs through problem statements. A company or group will submit a written statement of what they need and the shortcomings of commercially available technology. The Technology Transfer Team (T3) reviews these problem statements and decides where NASA LaRC can offer assistance. A researcher or group of researchers are then identified who can help solve the problem and they are put in contact with the company. Depending upon the situation in either method, a Space Act Agreement (SAA), or outline of the responsibilities for each party, is developed.

  13. Contact dermatoses in metal workers.

    PubMed

    Papa, G; Romano, A; Quaratino, D; Di Fonso, M; Viola, M; Sernia, S; Boccia, I; Di Gioacchino, M; Venuti, A; Calvieri, S

    2000-01-01

    We studied 150 metal workers occupationally exposed to metals and metalworking fluids (MWFs) to determine the prevalence and nature of contact dermatitis. 150 office workers were used as non-exposed control group. Questionnaires were administered to evaluate occupational and non-occupational exposure. All subjects underwent a dermatological examination and patch-testing with standard allergen series and MWFs used in the plant. Twenty-eight metal workers (18.6%) presented minor skin disorders involving the hands (vs. only 2% of the controls), ten (6.6%) had major disorders (similar to the figure for the control group - 5.4%), and 112 (74.8%) had no lesions, as opposed to 92.6% of the control group. Positive patch tests were found in ten metal workers: eight had major skin disorders (six to nickel, cobalt and chromium, one to nickel and cobalt, one to nickel) and the remaining two were asymptomatic (one positive for nickel and chromium, one for nickel). Among the controls there were three cases of positivity, all among asymptomatic subjects. Patch tests with MWFs were negative. The prevalence of dermatoses among the metal workers was significantly higher than that of controls (p<0.01), and all cases of allergy in this group were provoked by metals themselves.

  14. Charmonia in a contact interaction

    NASA Astrophysics Data System (ADS)

    Bedolla, Marco A.; Cobos-Martínez, J. J.; Bashir, Adnan

    2015-09-01

    For the flavor-singlet heavy quark system of charmonia, we compute the masses of the ground state mesons in four different channels: pseudoscalar [ηc(1 S )], vector [J /Ψ (1 S )], scalar [χc0(1P )] and axial vector [χc 1(1 P )], as well as the weak decay constants of the ηc(1 S ) and J /Ψ (1 S ) and the charge radius of ηc(1 S ). The framework for this analysis is provided by a symmetry-preserving Schwinger-Dyson equation (SDE) treatment of a vector×vector contact interaction. The results found for the meson masses and the weak decay constants, for the spin-spin combinations studied, are in fairly good agreement with experimental data and earlier model calculations based upon Schwinger-Dyson and Bethe-Salpeter equations involving sophisticated interaction kernels. The charge radius of ηc(1 S ) is consistent with the results from refined SDE studies and lattice quantum chromodynamics.

  15. Apparent contact angle and contact angle hysteresis on liquid infused surfaces

    NASA Astrophysics Data System (ADS)

    Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim

    We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a strong dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small but finite ridge, which corresponds to an effective line tension term. We also predict contact angle hysteresis on liquid infused surfaces generated by the pinning of the contact lines by the surface corrugations. Our analytical expressions for both the apparent contact angle and contact angle hysteresis can be interpreted as `weighted sums' between the contact angles of the infusing liquid relative to the droplet and surrounding gas phases, where the weighting coefficients are given by ratios of the fluid surface tensions.

  16. Apparent contact angle and contact angle hysteresis on liquid infused surfaces.

    PubMed

    Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim

    2016-12-21

    We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small but finite ridge, which corresponds to an effective line tension term. We also predict contact angle hysteresis on liquid infused surfaces generated by the pinning of the contact lines by the surface corrugations. Our analytical expressions for both the apparent contact angle and contact angle hysteresis can be interpreted as 'weighted sums' between the contact angles of the infusing liquid relative to the droplet and surrounding gas phases, where the weighting coefficients are given by ratios of the fluid surface tensions.

  17. Enhanced End-Contacts by Helium Ion Bombardment to Improve Graphene-Metal Contacts

    PubMed Central

    Jia, Kunpeng; Su, Yajuan; Zhan, Jun; Shahzad, Kashif; Zhu, Huilong; Zhao, Chao; Luo, Jun

    2016-01-01

    Low contact resistance between graphene and metals is of paramount importance to fabricate high performance graphene-based devices. In this paper, the impact of both defects induced by helium ion (He+) bombardment and annealing on the contact resistance between graphene and various metals (Ag, Pd, and Pt) were systematically explored. It is found that the contact resistances between all metals and graphene are remarkably reduced after annealing, indicating that not only chemically adsorbed metal (Pd) but also physically adsorbed metals (Ag and Pt) readily form end-contacts at intrinsic defect locations in graphene. In order to further improve the contact properties between Ag, Pd, and Pt metals and graphene, a novel method in which self-aligned He+ bombardment to induce exotic defects in graphene and subsequent thermal annealing to form end-contacts was proposed. By using this method, the contact resistance is reduced significantly by 15.1% and 40.1% for Ag/graphene and Pd/graphene contacts with He+ bombardment compared to their counterparts without He+ bombardment. For the Pt/graphene contact, the contact resistance is, however, not reduced as anticipated with He+ bombardment and this might be ascribed to either inappropriate He+ bombardment dose, or inapplicable method of He+ bombardment in reducing contact resistance for Pt/graphene contact. The joint efforts of as-formed end-contacts and excess created defects in graphene are discussed as the cause responsible for the reduction of contact resistance.

  18. Ohmic contact to GaAs semiconductor

    NASA Technical Reports Server (NTRS)

    Hovel, H. J.; Woodall, J. M.

    1980-01-01

    Multimetallic layers produce stable, low-resistance contacts for p-type GaAs and p-type GaAlAs devices. Contacts present no leakage problems, and their series resistance is too small to measure at 1 Sun intensity. Ohmic contacts are stable and should meet 20-year-life requirement at 150 C for GaAs combined photothermal/photovoltaic concentrators.

  19. Contact angle measurements under thermodynamic equilibrium conditions.

    PubMed

    Lages, Carol; Méndez, Eduardo

    2007-08-01

    The precise control of the ambient humidity during contact angle measurements is needed to obtain stable and valid data. For a such purpose, a simple low-cost device was designed, and several modified surfaces relevant to biosensor design were studied. Static contact angle values for these surfaces are lower than advancing contact angles published for ambient conditions, indicating that thermodynamic equilibrium conditions are needed to avoid drop evaporation during the measurements.

  20. Process design for Al backside contacts

    SciTech Connect

    Chalfoun, L.L.; Kimerling, L.C.

    1995-08-01

    It is known that properly alloyed aluminum backside contacts can improve silicon solar cell efficiency. To use this knowledge to fullest advantage, we have studied the gettering process that occurs during contact formation and the microstructure of the contact and backside junction region. With an understanding of the alloying step, optimized fabrication processes can be designed. To study gettering, single crystal silicon wafers were coated with aluminim on both sides and subjected to heat treatments. Results are described.