Sample records for graphite throat insert

  1. Integral throat entrance development, qualification and production for the Antares 3 nozzle

    NASA Technical Reports Server (NTRS)

    Clayton, F. I.; Dirling, R. B.; Eitman, D. A.; Loomis, W. C.

    1982-01-01

    Although design analyses of a G-90 graphite integral throat entrance for the Antares 3 solid rocket motor nozzle indicated acceptable margins of safety, the nozzle throat insert suffered a thermostructural failure during the first development firing. Subsequent re-analysis using properties measured on material from the same billet as the nozzle throat insert showed negative margins. Carbon-carbon was investigated and found to result in large positive margins of safety. The G-90 graphite was replaced by SAI fast processed 4-D material which uses Hercules HM 10000 fiber as the reinforcement. Its construction allows powder filling of the interstices after preform fabrication which accelerates the densification process. Allied 15V coal tar pitch is then used to complete densification. The properties were extensively characterized on this material and six nozzles were subjected to demonstration, development and qualification firings.

  2. Thiokol 260-SL Nozzle Development Program

    DTIC Science & Technology

    1967-01-01

    Pigure 1 Candidate Throat Inserts ............................ 7 2 Laminate Temperature versus Coating Thickness for Selectron 5003 Specimens...32 Photo Cross Adhesive Pattern ....................... 111 33 Photo Parallel Adhesive Pattern ..................... 112 34 Adhesive Applicator Teeth ...Ablative Material .... 88 XXXIII Task 9: Corlar Coating of Graphite Materials Throat, IS 11004-01-02, 156-ZC-1 ............ ....... 90 XXXIV Adapter

  3. Investigation on Composite Throat Insert For Cryogenic Engines

    NASA Astrophysics Data System (ADS)

    Ayyappan, G.; Tiwari, S. B.; Praveen, RS; Mohankumar, L.; Jathaveda, M.; Ganesh, P.

    2017-02-01

    Injector element testing is an important step in the development and qualification of the cryogenic rocket engines. For the purpose of characterising the injectors, sub scale chambers are used. In order to assess the performance of the injectors, different configurations of the injectors are tested using a combustion chamber and a convergent-divergent nozzle. Pressure distribution along the wall of the chamber and throat insert is obtained from the CFD analysis and temperature distribution is obtained from thermal analysis. Thermo-structural analysis is carried out for the sub-scale model of throat inert using temperature dependent material properties. For the experiments a sub-scale model of the thrust chamber is realised. Injector element tests are carried out for the studies. The objective of the present study is to investigate the behaviour of different throat inserts, mainly graphite, 2-D Carbon-Carbon(2D C-C), 4-D Carbon-Carbon (4D C-C) and Silica Phenolic (SP), under pressure and thermal load for repeated operation of the engine. Analytical results are compared with the test results. The paper gives the results of theoretical studies and experiments conducted with all the four type of throat material. It is concluded that 2D C-C is superior in terms of throat erosion being the least under specified combustion environment.

  4. Factors affecting the thermal shock behavior of yttria stabilized hafnia based graphite and tungsten composites.

    NASA Technical Reports Server (NTRS)

    Lineback, L. D.; Manning, C. R.

    1971-01-01

    Hafnia-based composites containing either graphite or tungsten were investigated as rocket nozzle throat inserts in solid propellant rocket engines. The thermal shock resistance of these materials is considered in terms of macroscopic thermal conductivity, thermal expansion, modulus of elasticity, and compressive fracture stress. The effect of degree of hafnia stabilization, density, and graphite or tungsten content upon these parameters is discussed. The variation of the ratio of elastic modulus to compressive fracture stress with density and its effect upon thermal shock resistance of these materials are discussed in detail.

  5. BSM Delta Qualification 2, volume 3, book 2

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This report, presented in three volumes, provides the results of a two-motor Delta Qualification 2 program conducted in 1993 to certify the following enhancements for incorporation into booster separation motor (BSM0 flight hardware: vulcanized-in-place nozzle aft closure insulation; new iso-static ATJ bulk graphite throat insert material, adhesive EA9394 for bonding the nozzle throat, igniter grain rod/centering insert/igniter case; deletion of the igniter adapter insulator ring; deletion of the igniter adapter/igniter case interface RTV; and deletion of loctite from igniter retainer plate threads. The enhancements above directly resulted from (1) the BSM total quality management (TQM) team initiatives to enhance the BSM producibility, and (2) the necessity to qualify new throat insert and adhesive systems to replace existing materials that will not be available. Testing was completed at both the component and motor levels. Component testing was accomplished to screen candidate materials (e.g., throat materials, adhesive systems) and to optimize processes (e.g., aft closure insulator vulcanization approach) prior to their incorporation into the test motors. Motor testing--consisting of two motors, randomly selected by USBI's on-site quality personnel from production lot AAY, which were modified to accept the enhancements -- was completed to provide the final qualification of the enhancements for incorporation into flight hardware. Volume 3, Book 2 provides various supporting documentation to the previous volumes with regards to the testing of the two Delta qualification units: data acceptance records, thermal conditioning analysis, igniter adapter thermal flake analysis, laboratory adhesive (EA-9394) qualification report, throat insert thermal/structural analysis, Delta Qualification Nonconformance Reports (NCR's), O-ring seating tests, and interim test report for vulcanization process qualification.

  6. BSM Delta qualification 2, volume 1

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This report, presented in three volumes, provides the results of a two-motor Delta Qualification 2 program conducted in 1993 to certify the following enhancements for incorporation into Booster Separation Motor (BSM) flight hardware: (1) vulcanized-in-place nozzle aft closure insulation; (2) new isostatic ATJ bulk graphite throat insert material; (3) adhesive EA 9394 for bonding the nozzle throat, igniter grain rod/centering insert/igniter case; (4) deletion of the igniter adapter insulator ring; (5) deletion of igniter adapter/igniter case interface RTV; and (6) deletion of Loctite from igniter retainer plate threads. The enhancements above directly resulted from (1) the BSM Total Quality Management (TQM) Team initiatives to enhance the BSM producibility, and (2) the necessity to qualify new throat insert and adhesive systems to replace existing materials that will not be available. Testing was completed at both the component and motor levels. Component testing was accomplished to screen candidate materials (e.g., throat materials, adhesive systems) and to optimize processes (e.g., aft closure insulator vulcanization approach) prior to their incorporation into the test motors. Motor testing - consisting of two motors, randomly selected by USBI's onsite quality personnel from production lot AAY, which were modified to accept the enhancements - were completed to provide the final qualification of the enhancements for incorporation into flight hardware. It is concluded that all of the enhancements herein tested are qualified to be incorporated into flight hardware for the BSM.

  7. BSM Delta Qualification 2, volume 2

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This report, presented in three volumes, provides the results of a two-motor Delta Qualification 2 program conducted in 1993 to certify the following enhancements for incorporation into booster separation motor (BSM) flight hardware: vulcanized-in-place nozzle aft closure insulation; new iso-static ATJ bulk graphite throat insert material; adhesive EA 9394 for bonding the nozzle throat, igniter grain rod/centering insert/igniter case; deletion of the igniter adapter insulator ring; deletion of the igniter adapter/igniter case interface RTV; and deletion of loctite from igniter retainer plate threads. The enhancements above directly resulted from (1) the BSM total quality management (TQM) team initiatives to enhance the BSM producibility, and (2) the necessity to qualify new throat insert and adhesive systems to replace existing materials that will not be available. Testing was completed at both the component and motor levels. Component testing was accomplished to screen candidate materials (e.g., throat materials, adhesive systems) and to optimize processes (e.g., aft closure insulator vulcanization approach) prior to their incorporation into the test motors. Motor tests -- consisting of two motors, randomly selected by USBI's on-site quality personnel from production lot AAY, which were modified to accept the enhancements -- were completed to provide the final qualification of the enhancements for incorporation into flight hardware. Volume 2 details the environmental testing (vibration and shock) conducted at Marshall Space Flight Center (MSFC) to which the motors were subjected prior to static tests.

  8. BSA Delta Qualification 2, volume 3, book 1

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This report, presented in three volumes, provides the results of a two-motor Delta Qualification 2 program conducted in 1993 to certify the following enhancements for incorporation into booster separation motor (BSM) flight hardware: vulcanized-in-place nozzle aft closure insulation; new iso-static ATJ bulk graphite throat insert material; adhesive EA 9394 for bonding the nozzle throat, igniter grain rod/centering insert/igniter case; deletion of the igniter adapter insulator ring; deletion of the igniter adapter/igniter case interface RTV; and deletion of Loctite from igniter retainer plate threads. The enhancements above directly resulted from (1) the BSM total quality management (TQM) team initiatives to enhance the BSM producibility, and (2) the necessity to qualify new throat insert and adhesive systems to replace existing materials that will not be available. Testing was completed at both the component and motor levels. Component testing was accomplished to screen candidate materials (e.g., throat materials, adhesive systems) and to optimize processes (e.g., aft closure insulator vulcanization approach) prior to their incorporation into the test motors. Motor tests -- consisting of two motors, randomly selected by USBI's on-site quality personnel from production lot AAY, which were modified to accept the enhancements -- were completed to provide the final qualification of the enhancements for incorporation into flight hardware. Volume 3 book 1 provides supporting documentation to the analyses and plans of testing the two Delta Qualification units including thermal cycling planning/data acceptance records, environmental test procedures and pretest temperature conditioning history, Delta Qualification test plan, and specification SE0837 -- mix acceptance test specification.

  9. Finite Element Simulation of Solid Rocket Booster Separation Motors During Motor Firing

    NASA Technical Reports Server (NTRS)

    Yu. Weiping; Crane, Debora J.

    2007-01-01

    One of the toughest challenges facing Solid Rocket Booster (SRB) engineers is to ensure that any design changes made to the Shuttle-Derived Booster Separation Motors (BSM) for future space exploration vehicles is able to withstand the increasingly hostile motor firing environment without cracking its critical component - the graphite throat. This paper presents a critical analysis methodology and techniques for assessing effects of BSM design changes with great accuracy and precision. For current Space Shuttle operation, the motor firing occurs at SRB separation - approximately 125 seconds after Shuttle launch at an altitude of about 28 miles. The motor operation event lasts about two seconds, however, the surface temperature of the graphite throat increases approximately 3400 F in less than one second with a corresponding increase in surface pressure of approximately 2200 pounds per square inch (psi) in less than one-tenth of a second. To capture this process fully and accurately, a two-phase sequentially coupled thermal-mechanical finite element approach was developed. This method allows the time- and location-dependent pressure fields to interact with the spatial-temporal thermal fields throughout the operation. The material properties of graphite throat are orthotropic and temperature-dependent. The analysis involves preload and multiple body contacts.

  10. A contrastive study of three graphite anodes in the piperidinium based electrolytes for lithium ion batteries

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

    Jiang, Xiao-Tao; Wang, Chen-Yi; Gao, Kun, E-mail: gaokun0451@163.com

    Graphical abstract: The fitting results of R{sub sei} and R{sub ct} of three graphite/Li cells. Besides three graphite/Li cells show the similar R{sub sei}, the NG198/Li cell demonstrates a higher R{sub ct} value in all test temperatures. Especially, the R{sub ct} at 333 K is even up to 355.8 Ω cm{sup 2}. Obviously, the narrow distribution of edge plane for NG198 caused this result, and then greatly restricts its cell capacity. By contrast, CMB with bigger specific surface area and more Li{sup +} insertion points shows lower resistance at room temperature, which should help to improve its capacity. - Highlights:more » • SEI film is closely related to graphite structures and formation temperature. • The graphite with bigger surface area and more Li{sup +} insertion points behaves better. • The graphite with narrow edge plane is uncompetitive for ionic liquid electrolyte. - Abstract: The electrochemical behaviors of natural graphite (NG198), artificial graphite (AG360) and carbon microbeads (CMB) in an ionic liquid based electrolyte are investigated by cyclic voltammetry (CV). The surface and structure of three graphite materials are characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) before and after cycling. It is found that solid electrolyte interface (SEI) is closely related to graphite structure. Benefiting from larger specific surface area and more dispersed Li{sup +} insertion points, CMB shows a better Li{sup +} insertion/de-insertion behavior than NG198 and AG360. Furthermore, electrochemical impedance spectra (EIS) prove that the SEI of different graphite electrodes has different intrinsic resistance and Li{sup +} penetrability. By comparison, CMB behaves better cell performances than AG360, while the narrow edge plane makes NG198 uncompetitive as a potential anode for the ionic liquids (ILs)-type Li-ion battery.« less

  11. Method of making a rocket nozzle

    NASA Technical Reports Server (NTRS)

    Campbell, D. H. (Inventor)

    1969-01-01

    A method is described for forming the interior of a nozzle having uneven walls so that a throat of smooth converging and diverging sides is provided for passing flow. A metallic insert material is placed within the flow passageway adjacent to the area where the sharper throat constriction is to be formed, so that the material will flow through the inlet into the throat space when liquefied.

  12. Preheating of streamlined liner of pharyngeal airway (SLIPA) reduced the related complications: a randomized control study.

    PubMed

    Geng, Guiqi; Chen, Yingjie; Liu, Hailian

    2017-06-01

    This study was designed to verify whether preheating could decrease the complications that may be associated with the use of streamlined liner of pharyngeal airway (SLIPA). We evaluated the incidence of sore throat, maximum sealing pressure, hoarseness and blood stains after preheating of SLIPA. Eighty patients scheduled for hysteroscopic surgery to whom the SLIPA was considered suitable were randomly allocated to preheating group or control group. The SLIPA in preheating group was placed in the incubator at 42 °C. The control group temperature was 24 °C. The mean maximum sealing pressure and duration of insertion were compared. Patients were interviewed at recovery room about sore throat and other complications. There were statistical differences in incidence of sore throat, severity of sore throat and blood stains between groups. However there was no statistical difference in the maximum sealing pressure. Our results suggest preheating of the SLIPA decreased the complications related with the insertion of SLIPA. Clinical Trials.gov Identifier NCT02539485.

  13. Thermal Analysis in Support of the Booster Separation Motor Crack Investigation

    NASA Technical Reports Server (NTRS)

    Davis, Darrell; Prickett, Terry; Turner, Larry D. (Technical Monitor)

    2001-01-01

    During a post-test inspection of a Booster Separation Motor (BSM) from a Lot Acceptance Test (LAT), a crack was noticed in the graphite throat. Since this was an out-of-family occurrence, an investigation team was formed to determine the cause of the crack. This paper will describe thermal analysis techniques used in support of this investigation. Models were generated to predict gradients in nominal motor conditions, as well as potentially anomalous conditions. Analysis was also performed on throats that were tested in the Laser Hardened Material Evaluation Laboratory (LHMEL). Some of these throats were pre-cracked, while others represented configurations designed to amplify effects of thermal stresses. Results from these analyses will be presented in this paper.

  14. Thermal Analysis in Support of the Booster Separation Motor Crack Investigation

    NASA Technical Reports Server (NTRS)

    Davis, Darrell; Prickett, Terry

    2002-01-01

    During a post-test inspection of a Booster Separation Motor (BSM) from a Lot Acceptance Test (LAT), a crack was noticed in the graphite throat. Since this was an out-of-family occurrence, an investigation team was formed to determine the cause of the crack. This paper will describe thermal analysis techniques used in support of this investigation. Models were generated to predict gradients in nominal motor conditions, as well as potentially anomalous conditions. Analysis was also performed on throats that were tested in the Laser Hardened Material Evaluation Laboratory (LHMEL). Some of these throats were pre-cracked, while others represented configurations designed to amplify effects of thermal stresses. Results from these analyses will be presented in this paper.

  15. The structure of graphene oxide membranes in liquid water, ethanol and water-ethanol mixtures

    NASA Astrophysics Data System (ADS)

    Talyzin, Alexandr V.; Hausmaninger, Tomas; You, Shujie; Szabó, Tamás

    2013-12-01

    The structure of graphene oxide (GO) membranes was studied in situ in liquid solvents using synchrotron radiation X-ray diffraction in a broad temperature interval. GO membranes are hydrated by water similarly to precursor graphite oxide powders but intercalation of alcohols is strongly hindered, which explains why the GO membranes are permeated by water and not by ethanol. Insertion of ethanol into the membrane structure is limited to only one monolayer in the whole studied temperature range, in contrast to precursor graphite oxide powders, which are intercalated with up to two ethanol monolayers (Brodie) and four ethanol monolayers (Hummers). As a result, GO membranes demonstrate the absence of ``negative thermal expansion'' and phase transitions connected to insertion/de-insertion of alcohols upon temperature variations reported earlier for graphite oxide powders. Therefore, GO membranes are a distinct type of material with unique solvation properties compared to parent graphite oxides even if they are composed of the same graphene oxide flakes.The structure of graphene oxide (GO) membranes was studied in situ in liquid solvents using synchrotron radiation X-ray diffraction in a broad temperature interval. GO membranes are hydrated by water similarly to precursor graphite oxide powders but intercalation of alcohols is strongly hindered, which explains why the GO membranes are permeated by water and not by ethanol. Insertion of ethanol into the membrane structure is limited to only one monolayer in the whole studied temperature range, in contrast to precursor graphite oxide powders, which are intercalated with up to two ethanol monolayers (Brodie) and four ethanol monolayers (Hummers). As a result, GO membranes demonstrate the absence of ``negative thermal expansion'' and phase transitions connected to insertion/de-insertion of alcohols upon temperature variations reported earlier for graphite oxide powders. Therefore, GO membranes are a distinct type of material with unique solvation properties compared to parent graphite oxides even if they are composed of the same graphene oxide flakes. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr04631a

  16. A comparative study of graphite electrodes using the co-intercalation phenomenon for rechargeable Li, Na and K batteries.

    PubMed

    Kim, Haegyeom; Yoon, Gabin; Lim, Kyungmi; Kang, Kisuk

    2016-10-18

    Here, we demonstrate that graphite can serve as a versatile electrode for various rechargeable battery types by reversibly accommodating solvated alkali ions (such as K, Na, and Li) through co-intercalation in its galleries. The co-intercalation of alkali ions is observed to occur via staging reactions. Notably, their insertion behaviors, including their specific capacity, are remarkably similar regardless of the alkali ion species despite the different solubility limits of K, Na, and Li ions in graphite. Nevertheless, the insertion potentials of the solvated alkali ions differ from each other and are observed to be correlated with the interlayer distance in the intercalated graphite gallery.

  17. Crack cause analysis of a graphite nozzle throat insert

    NASA Astrophysics Data System (ADS)

    Sun, Lin; Bao, Futing; Zhao, Yu; Hou, Lian; Hui, Weihua; Zhang, Ning; Shi, Wei

    2017-08-01

    With an objective to determine the failure cause of a throughout crack at an angle of 45° and a breach during a firing test, a simplified analysis procedure with consideration of the structure gap was established to simulate the thermo-structural response of a nozzle. By neglecting erosion and pyrolysis of the insulating materials and establishing temperature-dependent or anisotropic material models, ANSYS Parameter Design Language codes were written to perform the fully coupled thermal-structural simulation. A Quasi-1D flow was calculated for supplying boundary conditions. Study on mesh independence and time step independence was also conducted to evaluate simulated results. It was found that shortly after ignition, compressive stress in the x direction and tensile stress in the y direction contributed to anomalies. And through contact status analysis, inappropriate gap design was regarded as the origin of the too large stress, which was the primary cause of these anomalies during firing test. Simulation results were in good agreement with firing test results. In addition, the simplified analysis procedure was proven effective. Gap size should be seriously dealt with in the future design.

  18. Treatment of Postoperative Sore Throat With the Aid of the Homeopathic Remedy Arnica montana: A Report of Two Cases.

    PubMed

    Tsintzas, Dionysis; Vithoulkas, George

    2017-10-01

    We present 2 cases of severe postoperative sore throat, hoarseness, aphonia, and dysphagia, after a laryngeal mask insertion, who were treated successfully with the homeopathic remedy Arnica montana. Three doses of Arnica montana 200CH were given to the patients over 36 hours. Although the symptoms were very intense, the remedy was very effective and cleared most of the symptoms in 48 hours.

  19. Treatment of Postoperative Sore Throat With the Aid of the Homeopathic Remedy Arnica montana: A Report of Two Cases

    PubMed Central

    Tsintzas, Dionysis; Vithoulkas, George

    2017-01-01

    We present 2 cases of severe postoperative sore throat, hoarseness, aphonia, and dysphagia, after a laryngeal mask insertion, who were treated successfully with the homeopathic remedy Arnica montana. Three doses of Arnica montana 200CH were given to the patients over 36 hours. Although the symptoms were very intense, the remedy was very effective and cleared most of the symptoms in 48 hours. PMID:29228804

  20. Casting of weldable graphite/magnesium metal matrix composites with built-in metallic inserts

    NASA Technical Reports Server (NTRS)

    Lee, Jonathan A.; Kashalikar, Uday; Majkowski, Patricia

    1994-01-01

    Technology innovations directed at the advanced development of a potentially low cost and weldable graphite/magnesium metal matrix composites (MMC) through near net shape pressure casting are described. These MMC components uniquely have built-in metallic inserts to provide an innovative approach for joining or connecting other MMC components through conventional joining techniques such as welding, brazing, mechanical fasteners, etc. Moreover, the metallic inserts trapped within the MMC components can be made to transfer the imposed load efficiently to the continuous graphite fiber reinforcement thus producing stronger, stiffer, and more reliable MMC components. The use of low pressure near net shape casting is economical compared to other MMC fabrication processes. These castable and potentially weldable MMC components can provide great payoffs in terms of high strength, high stiffness, low thermal expansion, lightweight, and easily joinable MMC components for several future NASA space structural, industrial, and commercial applications.

  1. Fully Coupled Aero-Thermochemical-Elastic Simulations of an Eroding Graphite Nozzle

    NASA Technical Reports Server (NTRS)

    Blades, E. L.; Reveles, N. D.; Nucci, M.; Maclean, M.

    2017-01-01

    A multiphysics simulation capability has been developed that incorporates mutual interactions between aerodynamics, structural response from aero/thermal loading, ablation/pyrolysis, heating, and surface-to-surface radiation to perform high-fidelity, fully coupled aerothermoelastic ablation simulations, which to date had been unattainable. The multiphysics framework couples CHAR (a 3-D implicit charring ablator solver), Loci/CHEM (a computational fluid dynamics solver for high-speed chemically reacting flows), and Abaqus (a nonlinear structural dynamics solver) to create a fully coupled aerothermoelastic charring ablative solver. The solvers are tightly coupled in a fully integrated fashion to resolve the effects of the ablation pyrolysis and charring process and chemistry products upon the flow field, the changes in surface geometry due to recession upon the flow field, and thermal-structural analysis of the body from the induced aerodynamic heating from the flow field. The multiphysics framework was successfully demonstrated on a solid rocket motor graphite nozzle erosion application. Comparisons were made with available experimental data that measured the throat erosion during the motor firing. The erosion data is well characterized, as the test rig was equipped with a windowed nozzle section for real-time X-ray radiography diagnostics of the instantaneous throat variations for deducing the instantaneous erosion rates. The nozzle initially undergoes a nozzle contraction due to thermal expansion before ablation effects are able to widen the throat. A series of parameters studies were conducted using the coupled simulation capability to determine the sensitivity of the nozzle erosion to different parameters. The parameter studies included the shape of the nozzle throat (flat versus rounded), the material properties, the effect of the choice of turbulence model, and the inclusion or exclusion of the mechanical thermal expansion. Overall, the predicted results match the experiment very well, and the predictions were able to bound the data within acceptable limits.

  2. Fail-Safe Pressure Plug

    NASA Technical Reports Server (NTRS)

    Svejkovsky, Paul A.

    1993-01-01

    Protective plug resists slowly built-up pressure or automatically releases itself if pressure rises suddenly. Seals out moisture at pressures ranging from 50 micrometers of mercury to 200 pounds per square inch. Designed to seal throat of 38 Reaction Control Thrusters on Space Shuttle protecting internal components from corrosion. Plug conforms to contour of nozzle throat, where O-ring forms pressure seal. After plug inserted, cover attached by use of cover-fitting assembly. Modified versions useful in protecting engines, pumps, reaction vessels, and other industrial equipment during shipment and maintenance.

  3. Bubble Departure from Metal-Graphite Composite Surfaces and Its Effects on Pool Boiling Heat Transfer

    NASA Technical Reports Server (NTRS)

    Chao, David F.; Sankovic, John M.; Motil, Brian J.; Yang, W-J.; Zhang, Nengli

    2010-01-01

    The formation and growth processes of a bubble in the vicinity of graphite micro-fiber tips on metal-graphite composite boiling surfaces and their effects on boiling behavior are investigated. It is discovered that a large number of micro bubbles are formed first at the micro scratches and cavities on the metal matrix in pool boiling. By virtue of the non-wetting property of graphite, once the growing micro bubbles touch the graphite tips, the micro bubbles are sucked by the tips and merged into larger micro bubbles sitting on the end of the tips. The micro bubbles grow rapidly and coalesce to form macro bubbles, each spanning several tips. The necking process of a detaching macro bubble is analyzed. It is revealed that a liquid jet is produced by sudden break-off of the bubble throat. The composite surfaces not only have higher temperatures in micro- and macrolayers but also make higher frequency of the bubble departure, which increase the average heat fluxes in both the bubble growth stage and in the bubble departure period. Based on these analyses, the enhancement mechanism of pool boiling heat transfer on composite surfaces is clearly revealed.

  4. Techniques for the insertion of the ProSeal laryngeal mask airway: comparison of the Foley airway stylet tool with the introducer tool in a prospective, randomized study.

    PubMed

    Chen, Mao-Kai; Hsu, Hung-Te; Lu, I-Cheng; Shih, Chih-Kai; Shen, Ya-Chun; Tseng, Kuang-Yi; Cheng, Kuang-I

    2014-01-01

    Many tools have been developed to facilitate the insertion of the ProSeal laryngeal mask airway (LMA) insertion, which can be impeded by folding of its soft cuff. The aim of this study was to compare the efficiency of ProSeal LMA insertion guided by a soft, direct optical Foley Airway Stylet Tool (FAST) with the standard introducer tool (IT). One hundred sixty patients undergoing general anesthesia using the ProSeal LMA as an airway management device were randomly allocated to either FAST-guided or IT-assisted groups. Following ProSeal LMA insertion, the glottic and esophageal openings were identified using a fiberoptic bronchoscope introduced through the airway and the drain tube. The primary outcomes were time taken to insert the ProSeal LMA and the success rate at the first attempt. Secondary end points included ease of insertion, hemodynamic response to insertion, and postoperative adverse events recorded in the recovery room and on the first postoperative morning. One hundred forty patients were included in the final analysis: 66 in the FAST-guided group and 74 in the IT-assisted group. The success rate of FAST device-guided ProSeal LMA insertion (95.7%) was broadly comparable with IT-assisted insertion (98.7%). However, the time taken to insert the ProSeal LMA was significantly longer when the FAST technique was used (p <0.001). The incidence of correct alignment of the airway tube and the drain tube did not differ significantly between the groups. There were no significant differences in ease of insertion or hemodynamic responses to insertion, except that the incidence of postoperative sore throat was significantly higher in the FAST group on the first postoperative day (22.2% compared with 6.8% in the IT group; p = 0.035). Both FAST-guided and IT-assisted techniques achieved correct ProSeal LMA positioning, but the IT technique was significantly quicker and less likely to cause a sore throat. ClinicalTrials.gov Identifier: NCT02048657.

  5. Fabrication of graphite/epoxy cases for orbit insertion motors

    NASA Technical Reports Server (NTRS)

    Schmidt, W. W.

    1973-01-01

    The fabrication procedures are described for filament-wound rocket motor cases, approximately 26.25 inches long by 25.50 inches diameter, utilizing graphite fibers. The process utilized prepreg tape which consists of Fortafil 4-R fibers in the E-759 epoxy resin matrix. This fabrication effect demonstrated an ability to fabricate high quality graphite/epoxy rocket motor cases in the 26.25 inch by 25.50 inch size range.

  6. Fundamental Investigation of Silicon Anode in Lithium-Ion Cells

    NASA Technical Reports Server (NTRS)

    Wu, James J.; Bennett, William R.

    2012-01-01

    Silicon is a promising and attractive anode material to replace graphite for high capacity lithium ion cells since its theoretical capacity is 10 times of graphite and it is an abundant element on Earth. However, there are challenges associated with using silicon as Li-ion anode due to the significant first cycle irreversible capacity loss and subsequent rapid capacity fade during cycling. Understanding solid electrolyte interphase (SEI) formation along with the lithium ion insertion/de-insertion kinetics in silicon anodes will provide greater insight into overcoming these issues, thereby lead to better cycle performance. In this paper, cyclic voltammetry and electrochemical impedance spectroscopy are used to build a fundamental understanding of silicon anodes. The results show that it is difficult to form the SEI film on the surface of a Si anode during the first cycle; the lithium ion insertion and de-insertion kinetics for Si are sluggish, and the cell internal resistance changes with the state of lithiation after electrochemical cycling. These results are compared with those for extensively studied graphite anodes. The understanding gained from this study will help to design better Si anodes, and the combination of cyclic voltammetry with impedance spectroscopy provides a useful tool to evaluate the effectiveness of the design modifications on the Si anode performance.

  7. Degradation of lithium ion batteries employing graphite negatives and nickel-cobalt-manganese oxide + spinel manganese oxide positives: Part 2, chemical-mechanical degradation model

    NASA Astrophysics Data System (ADS)

    Purewal, Justin; Wang, John; Graetz, Jason; Soukiazian, Souren; Tataria, Harshad; Verbrugge, Mark W.

    2014-12-01

    Capacity fade is reported for 1.5 Ah Li-ion batteries containing a mixture of Li-Ni-Co-Mn oxide (NCM) + Li-Mn oxide spinel (LMO) as positive electrode material and a graphite negative electrode. The batteries were cycled at a wide range of temperatures (10 °C-46 °C) and discharge currents (0.5C-6.5C). The measured capacity losses were fit to a simple physics-based model which calculates lithium inventory loss from two related mechanisms: (1) mechanical degradation at the graphite anode particle surface caused by diffusion-induced stresses (DIS) and (2) chemical degradation caused by lithium loss to continued growth of the solid-electrolyte interphase (SEI). These two mechanisms are coupled because lithium is consumed through SEI formation on newly exposed crack surfaces. The growth of crack surface area is modeled as a fatigue phenomenon due to the cyclic stresses generated by repeated lithium insertion and de-insertion of graphite particles. This coupled chemical-mechanical degradation model is consistent with the observed capacity loss features for the NCM + LMO/graphite cells.

  8. Effects of anode material on arcjet performance

    NASA Technical Reports Server (NTRS)

    Sankovic, John M.; Curran, Frank M.; Larson, C. A.

    1992-01-01

    Anodes fabricated from four different materials were tested in a modular arcjet thruster at 1 kW power level on nitrogen/hydrogen mixtures. A two-percent thoriated tungsten anode served as the control. Graphite was chosen for its ease in fabrication, but experienced severe erosion in the constrictor and diverging side. Hafnium carbide and lanthanum hexaboride were chosen for their low work functions but failed due to thermal stress and reacted with the propellant. When compared to the thoriated tungsten nozzle, thruster performance was significantly lower for the lanthanum hexaboride insert and the graphite nozzle, but was slightly higher for the hafnium carbide nozzle. Both the lanthanum hexaboride and hafnium carbide nozzle operated at higher voltages. An attempt was made to duplicate higher performance hafnium carbide results, but repeated attempts at machining a second anode insert were unsuccessful. Graphite, hafnium carbide, and lanthanum hexaboride do not appear viable anode materials for low power arcjet thrusters.

  9. Fundamental Investigation of Si Anode in Li-Ion Cells

    NASA Technical Reports Server (NTRS)

    Wu, James J.; Bennett, William R.

    2012-01-01

    Silicon is a promising and attractive anode material to replace graphite for high capacity lithium ion cells since its theoretical capacity is approximately 10 times of graphite and it is an abundant element on earth. However, there are challenges associated with using silicon as Li-ion anode due to the significant first cycle irreversible capacity loss and subsequent rapid capacity fade during cycling. In this paper, cyclic voltammetry and electrochemical impedance spectroscopy are used to build a fundamental understanding of silicon anodes. The results show that it is difficult to form the SEI film on the surface of Si anode during the first cycle, the lithium ion insertion and de-insertion kinetics for Si are sluggish, and the cell internal resistance changes with the state of lithiation after electrochemical cycling. These results are compared with those for extensively studied graphite anodes. The understanding gained from this study will help to design better Si anodes.

  10. Molecular orientation of copper phthalocyanine thin films on different monolayers of fullerene on SiO{sub 2} or highly oriented pyrolytic graphite

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

    Wang, Chenggong; Wang, Congcong; Liu, Xiaoliang

    2015-03-23

    The interface electronic structures of copper phthalocyanine (CuPc) have been studied using ultraviolet photoemission spectroscopy as different monolayers of C{sub 60} were inserted between CuPc and a SiO{sub 2} or highly ordered pyrolytic graphite (HOPG) substrate. The results show that CuPc has standing up configuration with one monolayer of C{sub 60} insertion on SiO{sub 2} while lying down on HOPG, indicating that the insertion layer propagates the CuPc-substrate interaction. Meanwhile, CuPc on more than one monolayers of C{sub 60} on different substrates show that the substrate orientation effect quickly vanished. Our study elucidates intriguing molecular interactions that manipulate molecular orientationmore » and donor-acceptor energy level alignment.« less

  11. Pop tests of storable biopropellant liquid apogee engine

    NASA Astrophysics Data System (ADS)

    Kuroda, Yukio; Tadano, Makoto; Sato, Masahiro; Kusaka, Kazuo; Kobayashi, Hideyuki; Iihara, Sigeyasu; Ban, Hiroyuki

    1994-10-01

    A pressure-fed, blowdown, hydrazine/NTO apogee propulsion system had been selected for the ETS-6. One of the problems encountered during the development of the engine was the occurrence of pops (popping) at the higher operating chamber pressures. Pops are irregular high amplitude pressure pulses. It is generally agreed that pops is a liquid spray/gas two-phase explosion triggered by a local explosion near the jet impingement region. The effects of operating parameters on pops observed in the development tests of the apogee engine for the ETS-6 were inconsistent with those reported earlier for single impingement injectors; pops with the apogee engine injectors was more likely to occur at higher chamber pressures, higher injection velocities, and higher propellant temperatures. Pops data were correlated fairly well in chamber pressures (bar-P(sub c)) vs. fuel Reynolds number (R(sub ef)) plane. However, the range of operating parameters for the above correlation were very narrow since they were obtained during injector screening tests for a particular application to the apogee engine. It was also felt that the above correlation was too simplistic to capture any effect of design parameters of multi-element injectors. In the present study, the demarcation between pops and the pops-free region was determined in broader operating ranges and design parameters. The range of bar-P(sub c) and R(sub ef) was extended by exchanging graphite nozzle throat inserts with different throat diameters. The injectors were carefully selected to obtain effects, if any, of (1) film cooling fraction, (2) secondary mixing, and (3) number of elements and/or fuel orifice diameters. It was found that there was a threshold fuel Reynolds number below which no pops were observed at any chamber pressures and that the pops region curve in the bar-P(sub c)-R(sub ef) plane had two branches: upper branches and lower branches.

  12. Understanding the crack formation of graphite particles in cycled commercial lithium-ion batteries by focused ion beam - scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Lin, Na; Jia, Zhe; Wang, Zhihui; Zhao, Hui; Ai, Guo; Song, Xiangyun; Bai, Ying; Battaglia, Vincent; Sun, Chengdong; Qiao, Juan; Wu, Kai; Liu, Gao

    2017-10-01

    The structure degradation of commercial Lithium-ion battery (LIB) graphite anodes with different cycling numbers and charge rates was investigated by focused ion beam (FIB) and scanning electron microscopy (SEM). The cross-section image of graphite anode by FIB milling shows that cracks, resulted in the volume expansion of graphite electrode during long-term cycling, were formed in parallel with the current collector. The crack occurs in the bulk of graphite particles near the lithium insertion surface, which might derive from the stress induced during lithiation and de-lithiation cycles. Subsequently, crack takes place along grain boundaries of the polycrystalline graphite, but only in the direction parallel with the current collector. Furthermore, fast charge graphite electrodes are more prone to form cracks since the tensile strength of graphite is more likely to be surpassed at higher charge rates. Therefore, for LIBs long-term or high charge rate applications, the tensile strength of graphite anode should be taken into account.

  13. Preventing Clogging In A Vacuum Plasma Spray Gun

    NASA Technical Reports Server (NTRS)

    Krotz, Phillip D.; Daniel, Ronald L., Jr.; Davis, William M.

    1994-01-01

    Modification of powder-injection ports enables lengthy, high-temperature deposition operations. Graphite inserts prevent clogging of ports through which copper powder injected into vacuum plasma spray (VPS) gun. Graphite liners eliminate need to spend production time refurbishing VPS gun, reducing cost of production and increasing productivity. Concept also applied to other material systems used for net-shape fabrication via VPS.

  14. Effect of ITE and nozzle exit cone erosion on specific impulse of solid rocket motors

    NASA Astrophysics Data System (ADS)

    Smith-Kent, Randall; Ridder, Jeffrey P.; Loh, Hai-Tien; Abel, Ralph

    1993-06-01

    Specific impulse loss due to the use of a slowly eroding integral throat entrance, or a throat insert, with a faster eroding nozzle exit cone is studied. It is suggested that an oblique shock wave produced by step-off erosion results in loss of specific impulse. This is studied by use of a shock capturing CFD method. The shock loss predictions for first-stage Peacekeeper and Castor 25 motors are found to match the trends of the test data. This work suggests that a loss mechanism, previously unaccounted, should be considered in the specific impulse prediction procedure for nozzles with step-off exit cone erosion.

  15. 21 CFR 874.4800 - Bone particle collector.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bone particle collector. 874.4800 Section 874.4800...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4800 Bone particle collector. (a) Identification. A bone particle collector is a filtering device intended to be inserted into a suction tube...

  16. 21 CFR 874.4800 - Bone particle collector.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Bone particle collector. 874.4800 Section 874.4800...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4800 Bone particle collector. (a) Identification. A bone particle collector is a filtering device intended to be inserted into a suction tube...

  17. 21 CFR 874.4800 - Bone particle collector.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Bone particle collector. 874.4800 Section 874.4800...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4800 Bone particle collector. (a) Identification. A bone particle collector is a filtering device intended to be inserted into a suction tube...

  18. 21 CFR 874.4800 - Bone particle collector.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Bone particle collector. 874.4800 Section 874.4800...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4800 Bone particle collector. (a) Identification. A bone particle collector is a filtering device intended to be inserted into a suction tube...

  19. 21 CFR 874.4800 - Bone particle collector.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Bone particle collector. 874.4800 Section 874.4800...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4800 Bone particle collector. (a) Identification. A bone particle collector is a filtering device intended to be inserted into a suction tube...

  20. Understanding the crack formation of graphite particles in cycled commercial lithium-ion batteries by focused ion beam - scanning electron microscopy

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

    Lin, Na; Jia, Zhe; Wang, Zhihui

    Here in this paper, the structure degradation of commercial Lithium-ion battery (LIB) graphite anodes with different cycling numbers and charge rates was investigated by focused ion beam (FIB) and scanning electron microscopy (SEM). The cross-section image of graphite anode by FIB milling shows that cracks, resulted in the volume expansion of graphite electrode during long-term cycling, were formed in parallel with the current collector. The crack occurs in the bulk of graphite particles near the lithium insertion surface, which might derive from the stress induced during lithiation and de-lithiation cycles. Subsequently, crack takes place along grain boundaries of the polycrystallinemore » graphite, but only in the direction parallel with the current collector. Furthermore, fast charge graphite electrodes are more prone to form cracks since the tensile strength of graphite is more likely to be surpassed at higher charge rates. Therefore, for LIBs long-term or high charge rate applications, the tensile strength of graphite anode should be taken into account.« less

  1. Understanding the crack formation of graphite particles in cycled commercial lithium-ion batteries by focused ion beam - scanning electron microscopy

    DOE PAGES

    Lin, Na; Jia, Zhe; Wang, Zhihui; ...

    2017-10-01

    Here in this paper, the structure degradation of commercial Lithium-ion battery (LIB) graphite anodes with different cycling numbers and charge rates was investigated by focused ion beam (FIB) and scanning electron microscopy (SEM). The cross-section image of graphite anode by FIB milling shows that cracks, resulted in the volume expansion of graphite electrode during long-term cycling, were formed in parallel with the current collector. The crack occurs in the bulk of graphite particles near the lithium insertion surface, which might derive from the stress induced during lithiation and de-lithiation cycles. Subsequently, crack takes place along grain boundaries of the polycrystallinemore » graphite, but only in the direction parallel with the current collector. Furthermore, fast charge graphite electrodes are more prone to form cracks since the tensile strength of graphite is more likely to be surpassed at higher charge rates. Therefore, for LIBs long-term or high charge rate applications, the tensile strength of graphite anode should be taken into account.« less

  2. Adsorption of beryllium atoms and clusters both on graphene and in a bilayer of graphite investigated by DFT.

    PubMed

    Ferro, Yves; Fernandez, Nicolas; Allouche, Alain; Linsmeier, Christian

    2013-01-09

    We herein investigate the interaction of beryllium with a graphene sheet and in a bilayer of graphite by means of periodic DFT calculations. In all cases, we find the beryllium atoms to be more weakly bonded on graphene than in the bilayer. Be(2) forms both magnetic and non-magnetic structures on graphene depending on the geometrical configuration of adsorption. We find that the stability of the Be/bilayer system increases with the size of the beryllium clusters inserted into the bilayer of graphite. We also find a charge transfer from beryllium to the graphite layers. All these results are analysed in terms of electronic structure.

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

    Ferrario, Lorenzo, E-mail: lorenzo.ferrario@polimi.it; Little, Justin M., E-mail: jml@princeton.edu; Choueiri, Edgar Y., E-mail: choueiri@princeton.edu

    The plasma flow in a finite-electron-temperature magnetic nozzle, under the influence of an applied azimuthal current at the throat, is modeled analytically to assess its propulsive performance. A correction to the nozzle throat boundary conditions is derived by modifying the radial equilibrium of a magnetized infinite two-population cylindrical plasma column with the insertion of an external azimuthal body force for the electrons. Inclusion of finite-temperature effects, which leads to a modification of the radial density profile, is necessary for calculating the propulsive performance, which is represented by nozzle divergence efficiency and thrust coefficient. The solutions show that the application ofmore » the azimuthal current enhances all the calculated performance parameters through the narrowing of the radial density profile at the throat, and that investing power in this beam focusing effect is more effective than using the same power to pre-heat the electrons. The results open the possibility for the design of a focusing stage between the plasma source and the nozzle that can significantly enhance the propulsive performance of electron-driven magnetic nozzles.« less

  4. Prophylactic dexamethasone decreases the incidence of sore throat and hoarseness after tracheal extubation with a double-lumen endobronchial tube.

    PubMed

    Park, Sang-Hyun; Han, Sung-Hee; Do, Sang-Hwan; Kim, Jung-Won; Rhee, Ka-young; Kim, Jin-Hee

    2008-12-01

    Postoperative sore throat and hoarseness are common complications after tracheal intubation, particularly after using a double-lumen endobronchial tube (DLT). We conducted a prospective, randomized, double-blind, placebo-controlled study to evaluate the efficacy of dexamethasone for reducing the incidence and severity of postoperative sore throat and hoarseness. One hundred sixty-six patients (aged 18-75 yr) scheduled for thoracic surgery with a DLT were enrolled. Before induction of general anesthesia, 0.1 mg/kg dexamethasone (Group D1), 0.2 mg/kg dexamethasone (Group D2), or a placebo (Group P) were infused i.v. in a double-blind and prospectively randomized manner. Glottic exposure as defined by Cormack and Lehane score, resistance to DLT insertion, number of intubation attempts, time to achieve intubation, and the duration of tracheal intubation were recorded. At 1 h and 24 h after tracheal extubation, the patients were evaluated for sore throat and hoarseness using a visual analog scale (VAS; where 0 = no pain and 100 = worst pain imaginable). One hour after tracheal extubation, the incidence of postoperative sore throat and hoarseness, along with the severity of sore throat were lower in Group D1 (31%, P = 0.021; 11%, P = 0.003; and VAS 12.4, P < 0.001, respectively) and D2 (11%, P = 0.001; 4%, P = 0.001; and VAS 6.6, P < 0.001, respectively) compared with Group P (53%, 36% and VAS 30.9, respectively). Twenty-four hours after tracheal extubation, the incidence of postoperative sore throat, hoarseness, and the severity of sore throat were significantly lower in Group D2 (27%, P = 0.002; 15%, P = 0.001; and VAS 29.9, P < 0.002, respectively) compared with Group D1 (47%, 31%, and VAS = 43.9, respectively) and Group P (57%, 45%, and VAS = 51.3, respectively). There was no complication associated with the dexamethasone administration. The prophylactic use of 0.2 mg/kg of dexamethasone significantly decreases the incidence and severity of sore throat and hoarseness 1 h and 24 h after tracheal extubation of a DLT.

  5. Thulium-170 heat source

    DOEpatents

    Walter, Carl E.; Van Konynenburg, Richard; VanSant, James H.

    1992-01-01

    An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.

  6. AFRPL Graphite Performance Prediction Program. Improved Capability for the Design and Ablation Performance Prediction of Advanced Air Force Solid Propellant Rocket Nozzles

    DTIC Science & Technology

    1976-12-01

    corrosive attack by both acids and alkali and, in addition, is provided with a special Dynel veil for protection against fluoride attack. 3.1.4...throat region, namely , the entrance, center, and exit. In addition, at each station, the diameters were determined at two angular positions 90° apart. The...characterization test matrix. 3.2.1.1 Rocket Motor Environments Rocket motor environments were based on three advanced MX propellants, namely , * XLDB * HTPB * PEG

  7. Breathing of Graphite Particles in a Lithium-Ion Battery

    NASA Astrophysics Data System (ADS)

    Takata, Keiji; Okuda, Mitsuhiro; Yura, Nobuki; Tamura, Ryota

    2012-04-01

    We imaged changes in volume of graphite particles in a Li-ion battery due to the insertion and extraction of Li ions using scanning probe microscopy. When Li ions were extracted from the graphite particles, the particles were contracted, while expansion was induced in the interspaces between the particles. Variations of the images of volume changes depending on modulation frequencies clearly showed lithium intercalation. A linear relationship between the amplitudes of volume changes and the products of the diffusion elements and the reciprocals of the frequencies has been proven. Thus, the detected signals quantitatively well corresponded to the lithium ion movements.

  8. An Investigation of Convergent-Divergent Diffusers at Mach Number 1.85

    NASA Technical Reports Server (NTRS)

    Wyatt, Demarquis D; Hunczak, Henry R

    1947-01-01

    An investigation has been conducted in the Cleveland 18- by 18-inch supersonic tunnel at a Mach number of 1.85 and angles of attack from 0 deg to 5 deg to determine optimum design configurations for a convergent-divergent type of supersonic diffuser with a subsonic diffuser of 5 deg included divergence angle. Total pressure recoveries in excess of theoretical recovery across a normal shock at a free-stream Mach number of 1.85 wore obtained with several configurations. The highest recovery for configurations without a cylindrical throat section was obtained with an inlet having an included convergence angle of 20 deg. Insertion of a 2-inch throat section between a 10 deg included angle inlet and the subsonic diffuser stabilized the shock inside the diffuser and resulted in recoveries as high as 0.838 free-stream total pressure at an angle of attack of 0 deg, corresponding to recovery of 92.4 percent of the kinetic energy of the free air stream. Use of the throat section also lessened the reduction in recovery of all configurations due to angle of attack.

  9. Improved Rare-Earth Emitter Hollow Cathode

    NASA Technical Reports Server (NTRS)

    Goebel, Dan M.

    2011-01-01

    An improvement has been made to the design of the hollow cathode geometry that was created for the rare-earth electron emitter described in Compact Rare Earth Emitter Hollow Cathode (NPO-44923), NASA Tech Briefs, Vol. 34, No. 3 (March 2010), p. 52. The original interior assembly was made entirely of graphite in order to be compatible with the LaB6 material, which cannot be touched by metals during operation due to boron diffusion causing embrittlement issues in high-temperature refractory materials. Also, the graphite tube was difficult to machine and was subject to vibration-induced fracturing. This innovation replaces the graphite tube with one made out of refractory metal that is relatively easy to manufacture. The cathode support tube is made of molybdenum or molybdenum-rhenium. This material is easily gun-bored to near the tolerances required, and finish machined with steps at each end that capture the orifice plate and the mounting flange. This provides the manufacturability and robustness needed for flight applications, and eliminates the need for expensive e-beam welding used in prior cathodes. The LaB6 insert is protected from direct contact with the refractory metal tube by thin, graphite sleeves in a cup-arrangement around the ends of the insert. The sleeves, insert, and orifice plate are held in place by a ceramic spacer and tungsten spring inserted inside the tube. To heat the cathode, an insulating tube is slipped around the refractory metal hollow tube, which can be made of high-temperature materials like boron nitride or aluminum nitride. A screw-shaped slot, or series of slots, is machined in the outside of the ceramic tube to constrain a refractory metal wire wound inside the slot that is used as the heater. The screw slot can hold a single heater wire that is then connected to the front of the cathode tube by tack-welding to complete the electrical circuit, or it can be a double slot that takes a bifilar wound heater with both leads coming out the back. This configuration replaces the previous sheathed heater design that limited the cycling-life of the cathode.

  10. On the Solidification and Structure Formation during Casting of Large Inserts in Ferritic Nodular Cast Iron

    NASA Astrophysics Data System (ADS)

    Tadesse, Abel; Fredriksson, Hasse

    2018-06-01

    The graphite nodule count and size distributions for boiling water reactor (BWR) and pressurized water reactor (PWR) inserts were investigated by taking samples at heights of 2160 and 1150 mm, respectively. In each cross section, two locations were taken into consideration for both the microstructural and solidification modeling. The numerical solidification modeling was performed in a two-dimensional model by considering the nucleation and growth in eutectic ductile cast iron. The microstructural results reveal that the nodule size and count distribution along the cross sections are different in each location for both inserts. Finer graphite nodules appear in the thinner sections and close to the mold walls. The coarser nodules are distributed mostly in the last solidified location. The simulation result indicates that the finer nodules are related to a higher cooling rate and a lower degree of microsegregation, whereas the coarser nodules are related to a lower cooling rate and a higher degree of microsegregation. The solidification time interval and the last solidifying locations in the BWR and PWR are also different.

  11. Lithium insertion in graphite from ternary ionic liquid-lithium salt electrolytes: II. Evaluation of specific capacity and cycling efficiency and stability at room temperature

    NASA Astrophysics Data System (ADS)

    Lux, Simon F.; Schmuck, Martin; Appetecchi, Giovanni B.; Passerini, Stefano; Winter, Martin; Balducci, Andrea

    In this paper we report the results about the use of ternary room temperature ionic liquid-lithium salt mixtures as electrolytes for lithium-ion battery systems. Mixtures of N-methyl- N-propyl pyrrolidinium bis(fluorosulfonyl) imide, PYR 13FSI, and N-butyl- N-methylpyrrolidinium bis(trifluoromethansulfonyl) imide, PYR 14TFSI, with lithium hexafluorophosphate, LiPF 6 and lithium bis(trifluoromethansulfonyl) imide, LiTFSI, containing 5 wt.% of vinylene carbonate (VC) as additive, have been used in combination with a commercial graphite, KS6 TIMCAL. The performance of the graphite electrodes has been considered in term of specific capacity, cycling efficiency and cycling stability. The results clearly show the advantage of the use of ternary mixtures on the performance of the graphite electrode.

  12. Lamination residual strains and stresses in hybrid laminates

    NASA Technical Reports Server (NTRS)

    Daniel, I. M.; Liber, T.

    1977-01-01

    An investigation is conducted of the effects of hybridization on the magnitude of lamination residual stresses. Eight-ply graphite/Kevlar 49/epoxy and graphite/S-glass/epoxy laminates were studied. The same matrix resin was selected for all basic materials to ensure compatibility and uniform curing of the various plies. The specimens, with inserted strain gages and thermocouples, were subjected to curing and postcuring cycles in an autoclave. Subsequently, the specimens were subjected to a thermal cycle from room temperature to 444 K and down to room temperature. It was found that hydridizing reduces apparently residual strains and stresses in the graphite plies. However, these strains were not affected much by the type and degree of hybridization.

  13. Conductive Composites Made Less Expensively

    NASA Technical Reports Server (NTRS)

    Gaier, James R.

    2005-01-01

    The use of electrically conductive composite structures for electrostatic dissipation, electromagnetic interference shielding, and ground return planes could save between 30 and 90 percent of the mass of the structure, in comparison to aluminum. One strategy that has been shown to make conducting composites effectively uses intercalated graphite fiber as the reinforcement. Intercalation--the insertion of guest atoms or molecules between the graphene planes--can lower the electrical resistivity of graphite fibers by as much as a factor of 10, without sacrificing mechanical or thermal properties.

  14. [Discovery of Chlamydia trachomatis in the throat during diagnosis of secondary syphilis in an HIV+ patient].

    PubMed

    Deniaud, François; Scieux, Catherine; Spindler, Edith; Janier, Michel

    2003-09-20

    Chlamydia trachomatis (CT) pharyngitis has rarely been described in the literature. Studies in the last decade have shown a prevalence of less than 5%, with more women than men infected in the pharynx. Among homosexual men, only one study, conducted more than 5 years ago, detected the presence of CT in the throat (in one patient out of 13 tested). A 33 year-old homosexual man consulted for cutaneous lesions on the palms and the chest. Infected by HIV, he was taking antiretroviral therapy but no antibiotic prophylaxis. He admitted practising unprotected (insertive and receptive) fellatio with unknown partners. The lesions were those of secondary syphilis but the location of the chancre remained unknown. An enlarged screening for sexually transmitted infections detected the presence, through molecular amplification, of CT in the throat without further localisation (urethra, anus). After intramuscular injection of Extencillin and an 8-day-regimen of cycline, CT was no longer detected in the throat. The course of HIV infection did not appear modified by this infectious episode. According to a review of the literature, the 4 most recent studies have not revealed CT in the throat of homosexuals although the bacteria was detected in the urethra of 3 to 4% of them. Chlamydia trachomatis is more frequently detected in the genital tract rather than the pharynx of women also screened in various localisations. These results must be tempered by the participant recruitment methods, diagnostic methods used, sample size and history of recent antibiotherapy. The pharyngeal mucosa might be less receptive to CT than the urethral mucosa. Association of CT pharyngitis with syphilis or its occurrence during HIV infection are not documented. The molecular amplification technique detects CT in the throat with sensitivity and specificity. A one-week regimen of cycline can cure this pharyngitis. Cost-effectiveness of screening for pharyngeal CT has not yet been assessed in persons 'at risk'.

  15. Thermal Pyrolytic Graphite Enhanced Components

    NASA Technical Reports Server (NTRS)

    Hardesty, Robert E. (Inventor)

    2015-01-01

    A thermally conductive composite material, a thermal transfer device made of the material, and a method for making the material are disclosed. Apertures or depressions are formed in aluminum or aluminum alloy. Plugs are formed of thermal pyrolytic graphite. An amount of silicon sufficient for liquid interface diffusion bonding is applied, for example by vapor deposition or use of aluminum silicon alloy foil. The plugs are inserted in the apertures or depressions. Bonding energy is applied, for example by applying pressure and heat using a hot isostatic press. The thermal pyrolytic graphite, aluminum or aluminum alloy and silicon form a eutectic alloy. As a result, the plugs are bonded into the apertures or depressions. The composite material can be machined to produce finished devices such as the thermal transfer device. Thermally conductive planes of the thermal pyrolytic graphite plugs may be aligned in parallel to present a thermal conduction path.

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

    Ganesh, Panchapakesan; Kent, Paul R; Mochalin, Vadym N

    We simulate the experimentally observed graphitization of nanodiamonds into multi-shell onion-like carbon nanostructures, also called carbon onions, at different temperatures, using reactive force fields. The simulations include long-range Coulomb and van der Waals interactions. Our results suggest that long-range interactions play a crucial role in the phase-stability and the graphitization process. Graphitization is both enthalpically and entropically driven and can hence be controlled with temperature. The outer layers of the nanodiamond have a lower kinetic barrier toward graphitization irrespective of the size of the nanodiamond and graphitize within a few-hundred picoseconds, with a large volume increase. The inner core ofmore » the nanodiamonds displays a large size-dependent kinetic barrier, and graphitizes much more slowly with abrupt jumps in the internal energy. It eventually graphitizes by releasing pressure and expands once the outer shells have graphitized. The degree of transformation at a particular temperature is thereby determined by a delicate balance between the thermal energy, long-range interactions, and the entropic/enthalpic free energy gained by graphitization. Upon full graphitization, a multi-shell carbon nanostructure appears, with a shell-shell spacing of about {approx}3.4 {angstrom} for all sizes. The shells are highly defective with predominantly five- and seven-membered rings to curve space. Larger nanodiamonds with a diameter of 4 nm can graphitize into spiral structures with a large ({approx}29-atom carbon ring) pore opening on the outermost shell. Such a large one-way channel is most attractive for a controlled insertion of molecules/ions such as Li ions, water, or ionic liquids, for increased electrochemical capacitor or battery electrode applications.« less

  17. Virtual impactor

    DOEpatents

    Yeh, Hsu-Chi; Chen, Bean T.; Cheng, Yung-Sung; Newton, George J.

    1988-08-30

    A virtual impactor having improved efficiency and low wall losses in which a core of clean air is inserted into the aerosol flow while aerosol flow is maintained adjacent inner wall surfaces of the focusing portion of the impactor. The flow rate of the core and the length of the throat of the impactor's collection probe, as well as the dimensional relationships of other components of the impactor adjacent the separation region of the impactor, are selected to optimize separation efficiency.

  18. Structural changes in a commercial lithium-ion battery during electrochemical cycling: An in situ neutron diffraction study

    NASA Astrophysics Data System (ADS)

    Sharma, Neeraj; Peterson, Vanessa K.; Elcombe, Margaret M.; Avdeev, Maxim; Studer, Andrew J.; Blagojevic, Ned; Yusoff, Rozila; Kamarulzaman, Norlida

    The structural response to electrochemical cycling of the components within a commercial Li-ion battery (LiCoO 2 cathode, graphite anode) is shown through in situ neutron diffraction. Lithuim insertion and extraction is observed in both the cathode and anode. In particular, reversible Li incorporation into both layered and spinel-type LiCoO 2 phases that comprise the cathode is shown and each of these components features several phase transitions attributed to Li content and correlated with the state-of-charge of the battery. At the anode, a constant cell voltage correlates with a stable lithiated graphite phase. Transformation to de-lithiated graphite at the discharged state is characterised by a sharp decrease in both structural cell parameters and cell voltage. In the charged state, a two-phase region exists and is composed of the lithiated graphite phase and about 64% LiC 6. It is postulated that trapping Li in the solid|electrolyte interface layer results in minimal structural changes to the lithiated graphite anode across the constant cell voltage regions of the electrochemical cycle.

  19. Formation, characterization, and dynamics of onion-like carbon structures for electrical energy storage from nanodiamonds using reactive force fields

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

    Ganesh, P.; Kent, P. R. C.; Mochalin, V.

    We simulate the experimentally observed graphitization of nanodiamonds into multi-shell onion-like carbonnanostructures, also called carbon onions, at different temperatures, using reactive force fields. The simulations include long-range Coulomb and van der Waals interactions. Our results suggest that long-range interactions play a crucial role in the phase-stability and the graphitization process. Graphitization is both enthalpically and entropically driven and can hence be controlled with temperature. The outer layers of the nanodiamond have a lower kinetic barrier toward graphitization irrespective of the size of the nanodiamond and graphitize within a few-hundred picoseconds, with a large volume increase. The inner core of themore » nanodiamonds displays a large size-dependent kinetic barrier, and graphitizes much more slowly with abrupt jumps in the internal energy. It eventually graphitizes by releasing pressure and expands once the outer shells have graphitized. The degree of transformation at a particular temperature is thereby determined by a delicate balance between the thermal energy, long-range interactions, and the entropic/enthalpic free energy gained by graphitization. Upon full graphitization, a multi-shell carbonnanostructure appears, with a shell-shell spacing of about ~3.4 Å for all sizes. The shells are highly defective with predominantly five- and seven-membered rings to curve space. Larger nanodiamonds with a diameter of 4 nm can graphitize into spiral structures with a large (~29-atom carbon ring) pore opening on the outermost shell. Such a large one-way channel is most attractive for a controlled insertion of molecules/ions such as Li ions, water, or ionic liquids, for increased electrochemical capacitor or battery electrode applications.« less

  20. Formation, characterization and dynamics of onion like carbon structures from nanodiamonds using reactive force-fields for electrical energy storage

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

    Kent, Paul R

    We simulate the experimentally observed graphitization of nanodiamonds into multi-shell onion-like carbon nanostructures, also called carbon onions, at different temperatures, using reactive force fields. The simulations include long-range Coulomb and van der Waals interactions. Our results suggest that long-range interactions play a crucial role in the phase-stability and the graphitization process. Graphitization is both enthalpically and entropically driven and can hence be controlled with temperature. The outer layers of the nanodiamond have a lower kinetic barrier toward graphitization irrespective of the size of the nanodiamond and graphitize within a few-hundred picoseconds, with a large volume increase. The inner core ofmore » the nanodiamonds displays a large size-dependent kinetic barrier, and graphitizes much more slowly with abrupt jumps in the internal energy. It eventually graphitizes by releasing pressure and expands once the outer shells have graphitized. The degree of transformation at a particular temperature is thereby determined by a delicate balance between the thermal energy, long-range interactions, and the entropic/enthalpic free energy gained by graphitization. Upon full graphitization, a multi-shell carbon nanostructure appears, with a shell-shell spacing of about {approx}3.4 {angstrom} for all sizes. The shells are highly defective with predominantly five- and seven-membered rings to curve space. Larger nanodiamonds with a diameter of 4 nm can graphitize into spiral structures with a large ({approx}29-atom carbon ring) pore opening on the outermost shell. Such a large one-way channel is most attractive for a controlled insertion of molecules/ions such as Li ions, water, or ionic liquids, for increased electrochemical capacitor or battery electrode applications.« less

  1. Nanospray mass spectrometry with indirect conductive graphite coating.

    PubMed

    Viberg, Peter; Nilsson, Staffan; Skog, Kerstin

    2004-07-15

    An easy and cost-effective method to manufacture a robust conductive graphite coating for nanospray mass spectrometry (nESI-MS) and capillary electrophoresis (CE)-nESI-MS is described. The method involves graphite coating of a tube sleeve, into which the nESI emitter is inserted and connected to a transfer capillary, instead of coating the actual emitter. The coating, made of graphite from a pencil and epoxy glue, was stable over long periods of use (>80 h) and showed excellent resistance toward various solvents. Stable electrospray was achieved in the investigated flow range (150-900 nL x min(-)(1)), and salbutamol, diphenhydramine, and nortriptyline (M(w): 239-263 g x mol(-)(1)) were detected in the nanomole per liter range during continuous pumping. CE-nESI-MS analysis gave excellent signal-to-noise ratios for 100-fmol injections. The technique allows simple exchange of the nESI emitter to suit a specific flow rate, and it minimizes risk of corona discharge.

  2. Web-structured graphitic carbon fiber felt as an interlayer for rechargeable lithium-sulfur batteries with highly improved cycling performance

    NASA Astrophysics Data System (ADS)

    Lee, Dong Kyu; Ahn, Chi Won; Jeon, Hwan-Jin

    2017-08-01

    Graphitic carbon fiber felt (GCFF) with a crystalline graphitic carbon structure was facilely prepared by a combination of electrospinning and graphitization (2800 °C heat treatment) and was used as an interlayer between the cathode and separator in Li-S batteries. This GCFF interlayer trapped the polysulfides on the cathode side and increased the utilization of sulfur by suppressing the shuttle phenomenon. Also, the GCFF was shown to be able to act as an upper current collector to reduce the charge-transfer resistance owing to the high crystallinity of the graphitic carbon fibers. The sulfur cathode with the GCFF interlayer showed a high specific initial discharge capacity of 1280.14 mAh g-1 and excellent cycling stability (1004.62 mAh g-1 after 100 cycles) at 0.2 C. Also, an image of the glass fiber (GF) separator on the anode side confirmed the presence of an SEI after 200 cycles, which apparently resulted from stable Li deposition on the Li metal because of the low or medium concentration of sulfur in the electrolyte solution. Our observations should contribute to elucidating the key features of complex three-dimensional carbon fabrics with crystalline graphitic structures that allow them, when inserted as interlayers, to markedly improve the performance of rechargeable batteries.

  3. Pencil graphite leads as simple amperometric sensors for microchip electrophoresis.

    PubMed

    Natiele Tiago da Silva, Eiva; Marques Petroni, Jacqueline; Gabriel Lucca, Bruno; Souza Ferreira, Valdir

    2017-11-01

    In this work we demonstrate, for the first time, the use of inexpensive commercial pencil graphite leads as simple amperometric sensors for microchip electrophoresis. A PDMS support containing one channel was fabricated through soft lithography and sanded pencil graphite leads were inserted into this channel to be used as working electrodes. The electrochemical and morphological characterization of the sensor was carried out. The graphite electrode was coupled to PDMS microchips in end-channel configuration and electrophoretic experiments were performed using nitrite and ascorbate as probe analytes. The analytes were successfully separated and detected in well-defined peaks with satisfactory resolution using the microfluidic platform proposed. The repeatability of the pencil graphite electrode was satisfactory (RSD values of 1.6% for nitrite and 12.3% for ascorbate, regarding the peak currents) and its lifetime was estimated to be ca. 700 electrophoretic runs over a cost of ca. $ 0.05 per electrode. The limits of detection achieved with this system were 2.8 μM for nitrite and 5.7 μM for ascorbate. For proof of principle, the pencil graphite electrode was employed for the real analysis of well water samples and nitrite was successfully quantified at levels below its maximum contaminant level established in Brazil and US. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Virtual impactor

    DOEpatents

    Yeh, H.C.; Chen, B.T.; Cheng, Y.S.; Newton, G.J.

    1988-08-30

    A virtual impactor is described having improved efficiency and low wall losses in which a core of clean air is inserted into the aerosol flow while aerosol flow is maintained adjacent to the inner wall surfaces of the focusing portion of the impactor. The flow rate of the core and the length of the throat of the impactor's collection probe, as well as the dimensional relationships of other components of the impactor adjacent the separation region of the impactor, are selected to optimize separation efficiency. 4 figs.

  5. Durability of Intercalated Graphite Epoxy Composites in Low Earth Orbit

    NASA Technical Reports Server (NTRS)

    Gaier, James R.; Davidson, Michelle L.; Shively, Rhonda

    1996-01-01

    The electrical conductivity of graphite epoxy composites can be substantially increased by intercalating (inserting guest atoms or molecules between the graphene planes) the graphite fibers before composite formation. The resulting high strength, low density, electrically conducting composites have been proposed for EMI shielding in spacecraft. Questions have been raised, however, about their durability in the space environment, especially with respect to outgassing of the intercalates, which are corrosive species such as bromine. To answer those concerns, six samples of bromine intercalated graphite epoxy composites were included in the third Evaluation of Oxygen Interaction with Materials (EOIM-3) experiment flown on the Space Shuttle Discovery (STS-46). Changes in electrical conductivity, optical reflectance, surface texture, and mass loss for SiO2 protected and unprotected samples were measured after being exposed to the LEO environment for 42 hours. SiO2 protected samples showed no degradation, verifying conventional protection strategies are applicable to bromine intercalated composites. The unprotected samples showed that bromine intercalation does not alter the degradation of graphite-epoxy composites. No bromine was detected to have been released by the fibers allaying fears that outgassing could be disruptive to the sensitive electronics the EMI shield is meant to protect.

  6. Production of graphene quantum dots by ultrasound-assisted exfoliation in supercritical CO2/H2O medium.

    PubMed

    Gao, Hanyang; Xue, Chen; Hu, Guoxin; Zhu, Kunxu

    2017-07-01

    In this research, three kinds of graphene quantum dots (GQDs)-pristine graphene quantum dots (PGQDs), expanded graphene quantum dots (EGQDs) and graphene oxide quantum dots (GOQDs)-were produced from natural graphite, expanded graphite, and oxide graphite respectively in an ultrasound-assisted supercritical CO 2 (scCO 2 )/H 2 O system. The effects of aqueous solution content ratio, system pressure, and ultrasonic power on the yields of different kinds of GQDs were investigated. According to these experiment results, the combination of the intense knocking force generated from high-pressure acoustic cavitation in a scCO 2 /H 2 O system and the superior penetration ability of scCO 2 was considered to be the key to the successful exfoliation of such tiny pieces from bulk graphite. An interesting result was found that, contrary to common experience, the yield of PGQDs from natural graphite was much higher than that of GOQDs from graphite oxide. Based on the experimental analysis, the larger interlayer resistance of natural graphite, which hindered the insertion of scCO 2 molecules, and the hydrophobic property of natural graphite surface, which made the planar more susceptible to the attack of ultrasonic collapsing bubbles, were deduced to be the two main reasons for this result. The differences in characteristics among the three kinds of GQDs were also studied and compared in this research. In our opinion, this low-cost and time-saving method may provide an alternative green route for the production of various kinds of GQDs, especially PGQDs. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Comparative analysis of emm type pattern of Group A Streptococcus throat and skin isolates from India and their association with closely related SIC, a streptococcal virulence factor

    PubMed Central

    Sagar, Vivek; Kumar, Rajesh; Ganguly, Nirmal K; Chakraborti, Anuradha

    2008-01-01

    Background Group A streptococcus (GAS) causes a wide variety of life threatening diseases in humans and the incidence of such infections is high in developing countries like India. Although distribution of emm types of GAS in India has been described, there is a lack of data describing either the comparative distribution of emm types in throat versus skin isolates, or the distribution of certain virulence factors amongst these isolates. Therefore in the present study we have monitored the emm type pattern of Group A streptococcus throat and skin isolates from India. Additionally, the association of these isolates with closely related sic (crs), a multifunctional compliment binding virulence factor, was also explored. Results Of the 94 (46 throat and 48 skin) isolates analyzed, 37 emm types were identified. The most frequently observed emm types were emm49 (8.5%) and emm112 (7.5%) followed by 6.5% each of emm1-2, emm75, emm77, and emm81. Out of 37 emm types, 27 have been previously reported and rest were isolated for the first time in the Indian Community. The predominant emm types of throat (emm49 and emm75) samples were different from those of skin (emm44, emm81 and emm112) samples. After screening all the 94 isolates, the crs gene was found in six emm1-2 (crs1-2) isolates, which was confirmed by DNA sequencing and expression analysis. Despite the polymorphic nature of crs, no intravariation was observed within crs1-2. However, insertions and deletions of highly variable sizes were noticed in comparison to CRS isolated from other emm types (emm1.0, emm57). CRS1-2 showed maximum homology with CRS57, but the genomic location of crs1-2 was found to be the same as that of sic1.0. Further, among crs positive isolates, speA was only present in skin samples thus suggesting possible role of speA in tissue tropism. Conclusion Despite the diversity in emm type pattern of throat and skin isolates, no significant association between emm type and source of isolation was observed. The finding that the crs gene is highly conserved even in two different variants of emm1-2 GAS (speA +ve and -ve) suggests a single allele of crs may be prevalent in the highly diverse throat and skin isolates of GAS in India. PMID:18796133

  8. Comparative analysis of emm type pattern of Group A Streptococcus throat and skin isolates from India and their association with closely related SIC, a streptococcal virulence factor.

    PubMed

    Sagar, Vivek; Kumar, Rajesh; Ganguly, Nirmal K; Chakraborti, Anuradha

    2008-09-16

    Group A streptococcus (GAS) causes a wide variety of life threatening diseases in humans and the incidence of such infections is high in developing countries like India. Although distribution of emm types of GAS in India has been described, there is a lack of data describing either the comparative distribution of emm types in throat versus skin isolates, or the distribution of certain virulence factors amongst these isolates. Therefore in the present study we have monitored the emm type pattern of Group A streptococcus throat and skin isolates from India. Additionally, the association of these isolates with closely related sic (crs), a multifunctional compliment binding virulence factor, was also explored. Of the 94 (46 throat and 48 skin) isolates analyzed, 37 emm types were identified. The most frequently observed emm types were emm49 (8.5%) and emm112 (7.5%) followed by 6.5% each of emm1-2, emm75, emm77, and emm81. Out of 37 emm types, 27 have been previously reported and rest were isolated for the first time in the Indian Community. The predominant emm types of throat (emm49 and emm75) samples were different from those of skin (emm44, emm81 and emm112) samples. After screening all the 94 isolates, the crs gene was found in six emm1-2 (crs1-2) isolates, which was confirmed by DNA sequencing and expression analysis. Despite the polymorphic nature of crs, no intravariation was observed within crs1-2. However, insertions and deletions of highly variable sizes were noticed in comparison to CRS isolated from other emm types (emm1.0, emm57). CRS1-2 showed maximum homology with CRS57, but the genomic location of crs1-2 was found to be the same as that of sic1.0. Further, among crs positive isolates, speA was only present in skin samples thus suggesting possible role of speA in tissue tropism. Despite the diversity in emm type pattern of throat and skin isolates, no significant association between emm type and source of isolation was observed. The finding that the crs gene is highly conserved even in two different variants of emm1-2 GAS (speA +ve and -ve) suggests a single allele of crs may be prevalent in the highly diverse throat and skin isolates of GAS in India.

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

    Gregoire, D.C.; Goltz, D.M.; Chakrabarti, C.L.

    Graphite furnace atomic absorption spectrometry (GFAAS) is an insensitive technique for determination of uranium. Experiments were conducted using electrothermal vaporization inductively coupled plasma mass spectrometry to investigate the atomization and vaporization of atomic and molecular uranium species in the graphite furnace. ETV-ICP-MS signals for uranium were observed at temperatures well below the appearance temperature of uranium atoms suggesting the vaporization of molecular uranium oxide at temperatures below 2000{degrees}C. Examination of individual uranium ETV-ICP-MS signals reveals the vaporization of uranium carbide at temperatures above 2600{degrees}C. Chemical modifiers such as 0.2% HF and 0.1% CHF{sub 3} in the argon carrier gas, weremore » ineffective in preventing the formation of uranium carbide at 2700{degrees}C. Vaporization of uranium from a tungsten surface using tungsten foil inserted into the graphite tube prevented the formation of uranium carbide and eliminated the ETV-ICP-MS signal suppression caused by a sodium chloride matrix.« less

  10. Low Reflection Absorbers for Electromagnetic Waves (Reflexionsarme Absorber Fuer Elektromagnetische Wellen)

    DTIC Science & Technology

    1960-11-01

    should be briefly recalled. They consist of air sound, as a rule, of porous substances, mineral wool , glass wool, and similar substances, whose...nonreflecting room, then small particles of graphite will -17- pi m u . I be inserted into the pores of the porous glass wool or mineral wool . Such wedges

  11. Manipulating Adsorption-Insertion Mechanisms in Nanostructured Carbon Materials for High-Efficiency Sodium Ion Storage

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

    Qiu, Shen; Xiao, Lifen; Sushko, Maria L.

    Hard carbon is one of the most promising anode materials for sodium-ion batteries, but the low coulombic efficiency is still a key barrier. In this paper we synthesized a series of nanostructured hard carbon materials with controlled architectures. Using a combination of in-situ XRD mapping, ex-situ NMR, EPR, electrochemical techniques and simulations, an “adsorption-intercalation” (A-I) mechanism is established for Na ion storage. During the initial stages of Na insertion, Na ions adsorb on the defect sites of hard carbon with a wide adsorption energy distribution, producing a sloping voltage profile. In the second stage, Na ions intercalate into graphitic layersmore » with suitable spacing to form NaCx compounds similar to the Li ion intercalation process in graphite, producing a flat low voltage plateau. The cation intercalation with a flat voltage plateau should be enhanced and the sloping region should be avoided. Guided by this knowledge, non-porous hard carbon material has been developed which has achieved high reversible capacity and coulombic efficiency to fulfill practical application.« less

  12. Studies of short-range tungsten migration in DIII-D divertor

    NASA Astrophysics Data System (ADS)

    Rudakov, D. L.; Stangeby, P. C.; Elder, J. D.; Ding, R.; Abrams, T.; Unterberg, E. A.; Briesemeister, A.; Donovan, D.; McLean, A. G.; Guo, H. Y.; Thomas, D. M.; Hinson, E.; Wampler, W. R.; Watkins, J. G.

    2016-10-01

    Two toroidal rings of 5 cm wide W-coated TZM inserts were installed in the lower divertor of DIII-D. Migration of W on the graphite tile surfaces 1-6 cm radially outwards from the outermost ring was studied in a series of 23 reproducible lower single null L-mode discharges with the Outer Strike Point (OSP) placed on the ring. The discharges used 3.2 MW of NBI heating power; plasma density and electron temperature at the OSP were about 1x1020m-3 and 30 eV. W gross erosion rates were measured via monitoring 400.9 nm WI line and applying S/XB coefficient. W deposition was measured on a graphite DiMES sample used as a divertor collector probe. The sample featured two 1 mm wide radial inserts; one was exposed for the whole experiment, the other was exchanged every 4-8 plasma discharges. Measurements of the areal density of W on the inserts by post-mortem RBS analysis show that W deposition is largest in the area of net carbon deposition, possibly due to W re-erosion suppression by C deposits. Measured W coverage in the area of net C erosion is comparable to ERO modeling predictions. Supported by US DOE under DE-FG02-07ER54917, DE-AC04-94AL85000, DE-AC05-00OR22725, DE-AC52-07NA27344, DE-FC02-04ER54698.

  13. Seal welded cast iron nuclear waste container

    DOEpatents

    Filippi, Arthur M.; Sprecace, Richard P.

    1987-01-01

    This invention identifies methods and articles designed to circumvent metallurgical problems associated with hermetically closing an all cast iron nuclear waste package by welding. It involves welding nickel-carbon alloy inserts which are bonded to the mating plug and main body components of the package. The welding inserts might be bonded in place during casting of the package components. When the waste package closure weld is made, the most severe thermal effects of the process are restricted to the nickel-carbon insert material which is far better able to accommodate them than is cast iron. Use of nickel-carbon weld inserts should eliminate any need for pre-weld and post-weld heat treatments which are a problem to apply to nuclear waste packages. Although the waste package closure weld approach described results in a dissimilar metal combination, the relative surface area of nickel-to-iron, their electrochemical relationship, and the presence of graphite in both materials will act to prevent any galvanic corrosion problem.

  14. Lithium insertion in graphite from ternary ionic liquid-lithium salt electrolytes. I. Electrochemical characterization of the electrolytes

    NASA Astrophysics Data System (ADS)

    Appetecchi, Giovanni B.; Montanino, Maria; Balducci, Andrea; Lux, Simon F.; Winterb, Martin; Passerini, Stefano

    In this paper we report the results of chemical-physical investigation performed on ternary room temperature ionic liquid-lithium salt mixtures as electrolytes for lithium-ion battery systems. The ternary electrolytes were made by mixing N-methyl- N-propyl pyrrolidinium bis(fluorosulfonyl) imide (PYR 13FSI) and N-butyl- N-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (PYR 14TFSI) ionic liquids with lithium hexafluorophosphate (LiPF 6) or lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The mixtures were developed based on preliminary results on the cyclability of graphite electrodes in the IL-LiX binary electrolytes. The results clearly show the beneficial synergic effect of the two ionic liquids on the electrochemical properties of the mixtures.

  15. Comparison on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fibre lasers

    NASA Astrophysics Data System (ADS)

    Yang, Chun-Yu; Lin, Yung-Hsiang; Wu, Chung-Lun; Cheng, Chih-Hsien; Tsai, Din-Ping; Lin, Gong-Ru

    2018-06-01

    Comparisons on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fiber lasers (EDFLs) are performed. As opposed to the graphite nano-particles obtained by physically triturating the graphite foil, the tri-layer graphene nano-sheets is obtained by electrochemically exfoliating the graphite foil. To precisely control the size dispersion and the layer number of the exfoliated graphene nano-sheet, both the bias of electrochemical exfoliation and the speed of centrifugation are optimized. Under a threshold exfoliation bias of 3 volts and a centrifugation at 1000 rpm, graphene nano-sheets with an average diameter of 100  ±  40 nm can be obtained. The graphene nano-sheets with an area density of 15 #/µm2 are directly imprinted onto the end-face of a single-mode fiber made patchcord connector inside the EDFL cavity. Such electrochemically exfoliated graphene nano-sheets show comparable saturable absorption with standard single-graphene and perform the self-amplitude modulation better than physically triturated graphite nano-particles. The linear transmittance and modulation depth of the inserted graphene nano-sheets are 92.5% and 53%, respectively. Under the operation with a power gain of 21.5 dB, the EDFL can be passively mode-locked to deliver a pulsewidth of 454.5 fs with a spectral linewidth of 5.6 nm. The time-bandwidth product of 0.31 is close to the transform limit. The Kelly sideband frequency spacing of 1.34 THz is used to calculate the chirp coefficient as  ‑0.0015.

  16. Pegasus - Winged workhorse

    NASA Astrophysics Data System (ADS)

    Furniss, Tim

    1988-08-01

    DARPA has initiated the development of a three-stage, solid-propellant air-launched booster for the lofting of small military satellites, or 'lightsats'. This vehicle, designated 'Pegasus', will because of its substantial endoatmospheric mission segment serve as a testbed for the validation of the CFD codes used by NASA as analytical tools in the design of the National Aerospace Plane. The three rocket stages are novel designs, incorporating such features as three-dimensionally woven carbon-carbon integral throat inserts and carbon-phenolic nozzles. The aircraft that will take Pegasus to launch altitude will be the B-52 previously used to launch the X-15.

  17. The effect of esophagogastroduodenoscopy probe insertion on the intracuff pressure of airway devices in children during general anesthesia.

    PubMed

    Balaban, Onur; Kamata, Mineto; Hakim, Mumin; Tumin, Dmitry; Tobias, Joseph D

    2017-04-01

    Given the size of the esophagogastroduodenoscopy (EGD) probe and the compressibility of the pediatric airway, the EGD probe may increase the intracuff pressure (IP) of an airway device. The current study evaluated IP changes during EGD examination under general anesthesia in pediatric patients. Following the induction of anesthesia, a laryngeal mask airway (LMA) or endotracheal tube (ETT) was placed without neuromuscular blockade. The IP was measured at baseline, during EGD probe insertion, while the EGD probe was in place, and after probe removal. The study cohort included 101 patients (mean age 11.3 years). The airway was secured with an LMA and an ETT in 88 and 13 patients, respectively. The IP increased from 27 ± 15 cmH 2 O at baseline to 34 ± 17 cmH 2 O during probe insertion (p < 0.001), remained at 33 ± 16 cmH 2 O while the probe was in place, and decreased to 26 ± 14 cmH 2 O after probe removal. The IP of the LMA or ETT increased during EGD probe insertion and remained elevated while the probe was in place. High IP may compromise mucosal perfusion resulting in a sore throat when using an LMA or the potential for airway damage if an ETT is used. Removal of air from the cuff and titration of the IP should be considered after EGD insertion.

  18. High Thermal Dissipation of Al Heat Sink When Inserting Ceramic Powders by Ultrasonic Mechanical Coating and Armoring

    PubMed Central

    Tsai, Wei-Yu; Huang, Guan-Rong; Wang, Kuang-Kuo; Chen, Chin-Fu; Huang, J. C.

    2017-01-01

    Aluminum alloys, which serve as heat sink in light-emitting diode (LED) lighting, are often inherent with a high thermal conductivity, but poor thermal total emissivity. Thus, high emissive coatings on the Al substrate can enhance the thermal dissipation efficiency of radiation. In this study, the ultrasonic mechanical coating and armoring (UMCA) technique was used to insert various ceramic combinations, such as Al2O3, SiO2, or graphite, to enhance thermal dissipation. Analytic models have been established to couple the thermal radiation and convection on the sample surface through heat flow equations. A promising match has been reached between the theoretical predictions and experimental measurements. With the adequate insertion of ceramic powders, the temperature of the Al heat sinks can be lowered by 5–11 °C, which is highly favorable for applications requiring cooling components. PMID:28772814

  19. High Thermal Dissipation of Al Heat Sink When Inserting Ceramic Powders by Ultrasonic Mechanical Coating and Armoring.

    PubMed

    Tsai, Wei-Yu; Huang, Guan-Rong; Wang, Kuang-Kuo; Chen, Chin-Fu; Huang, J C

    2017-04-26

    Aluminum alloys, which serve as heat sink in light-emitting diode (LED) lighting, are often inherent with a high thermal conductivity, but poor thermal total emissivity. Thus, high emissive coatings on the Al substrate can enhance the thermal dissipation efficiency of radiation. In this study, the ultrasonic mechanical coating and armoring (UMCA) technique was used to insert various ceramic combinations, such as Al₂O₃, SiO₂, or graphite, to enhance thermal dissipation. Analytic models have been established to couple the thermal radiation and convection on the sample surface through heat flow equations. A promising match has been reached between the theoretical predictions and experimental measurements. With the adequate insertion of ceramic powders, the temperature of the Al heat sinks can be lowered by 5-11 °C, which is highly favorable for applications requiring cooling components.

  20. A randomized prospective controlled trial comparing the laryngeal tube suction disposable and the supreme laryngeal mask airway: the influence of head and neck position on oropharyngeal seal pressure.

    PubMed

    Somri, Mostafa; Vaida, Sonia; Garcia Fornari, Gustavo; Mendoza, Gabriela Renee; Charco-Mora, Pedro; Hawash, Naser; Matter, Ibrahim; Swaid, Forat; Gaitini, Luis

    2016-10-06

    The Laryngeal Tube Suction Disposable (LTS-D) and the Supreme Laryngeal Mask Airway (SLMA) are second generation supraglottic airway devices (SADs) with an added channel to allow gastric drainage. We studied the efficacy of these devices when using pressure controlled mechanical ventilation during general anesthesia for short and medium duration surgical procedures and compared the oropharyngeal seal pressure in different head and-neck positions. Eighty patients in each group had either LTS-D or SLMA for airway management. The patients were recruited in two different institutions. Primary outcome variables were the oropharyngeal seal pressures in neutral, flexion, extension, right and left head-neck position. Secondary outcome variables were time to achieve an effective airway, ease of insertion, number of attempts, maneuvers necessary during insertion, ventilatory parameters, success of gastric tube insertion and incidence of complications. The oropharyngeal seal pressure achieved with the LTS-D was higher than the SLMA in, (extension (p=0.0150) and right position (p=0.0268 at 60 cm H 2 O intracuff pressures and nearly significant in neutral position (p = 0.0571). The oropharyngeal seal pressure was significantly higher with the LTS-D during neck extension as compared to SLMA (p= 0.015). Similar oropharyngeal seal pressures were detected in all other positions with each device. The secondary outcomes were comparable between both groups. Patients ventilated with LTS-D had higher incidence of sore throat (p = 0.527). No major complications occurred. Better oropharyngeal seal pressure was achieved with the LTS-D in head-neck right and extension positions , although it did not appear to have significance in alteration of management using pressure control mechanical ventilation in neutral position. The fiberoptic view was better with the SLMA. The post-operative sore throat incidence was higher in the LTS-D. ClinicalTrials.gov ID: NCT02856672 , Unique Protocol ID:BnaiZionMC-16-LG-001, Registered: August 2016.

  1. Compatibility of the Radio Frequency Mass Gauge with Graphite-Epoxy Composite Tanks

    NASA Technical Reports Server (NTRS)

    Zimmerli, G. A.; Mueller, C. H.

    2015-01-01

    The radio frequency mass gauge (RFMG) is a low-gravity propellant quantity gauge being developed at NASA for possible use in long-duration space missions utilizing cryogenic propellants. As part of the RFMG technology development process, we evaluated the compatibility of the RFMG with a graphite-epoxy composite material used to construct propellant tanks. The key material property that can affect compatibility with the RFMG is the electrical conductivity. Using samples of 8552/IM7 graphite-epoxy composite, we characterized the resistivity and reflectivity over a range of frequencies. An RF impedance analyzer was used to characterize the out-of-plane electrical properties (along the sample thickness) in the frequency range 10 to 1800 MHZ. The resistivity value at 500 MHz was 4.8 ohm-cm. Microwave waveguide measurements of samples in the range 1.7 - 2.6 GHz, performed by inserting the samples into a WR-430 waveguide, showed reflectivity values above 98%. Together, these results suggested that a tank constructed from graphite/epoxy composite would produce good quality electromagnetic tank modes, which is needed for the RFMG. This was verified by room-temperature measurements of the electromagnetic modes of a 2.4 m diameter tank constructed by Boeing from similar graphite-epoxy composite material. The quality factor Q of the tank electromagnetic modes, measured via RF reflection measurements from an antenna mounted in the tank, was typically in the range 400 less than Q less than 3000. The good quality modes observed in the tank indicate that the RFMG is compatible with graphite-epoxy tanks, and thus the RFMG could be used as a low-gravity propellant quantity gauge in such tanks filled with cryogenic propellants.

  2. Pechini process-derived tin oxide and tin oxide-graphite composites for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Zhang, R.; Lee, Jim Y.; Liu, Z. L.

    The Pechini process [Ceram. Bull. 68 (1989) 1002] is used to obtain fine tin oxide powders that reduce the specific volume change in Li + insertion and extraction reactions. The suitability of these tin oxides as active materials for negative electrodes in lithium-ion batteries is investigated. From elemental analysis, it is found that the templating polymer network is almost completely obliterated after heating at 500 °C. The best tin oxide does not exhibit extensive crystallization of tin atoms even after 30 cycles of alloying and de-alloying reactions with Li. The structure and the specific capacity of the oxides are dependent on the heat treatment and remnants of the polymeric CH network can impose an unfavorable outcome. A capacity of 600 mAh g -1, which is unchanged for 30 cycles, can be obtained from tin oxide heat treated at 1000 °C. Composites of graphite and SnO 2 are also prepared and exhibit synergistic interactions between graphite and tin oxide which are similar to those reported previously [Electrochem. Solid State Lett. 3 (2000) 167].

  3. Reconstruction of low-index graphite surfaces

    NASA Astrophysics Data System (ADS)

    Thinius, Sascha; Islam, Mazharul M.; Bredow, Thomas

    2016-07-01

    The low-index graphite surfaces (10 1 -0), (10 1 -1), (11 2 -0) and (11 2 - 1) have been studied by density functional theory (DFT) including van-der-Waals (vdW) corrections. Different from the (0001) surface which has been extensively investigated both experimentally and theoretically, there is no comprehensive study on the (10 1 -0)- (10 1 -1)-, (11 2 -0)- and (11 2 - 1)-surfaces available, although they are of relevance for Li insertion processes, e.g. in Li-ion batteries. In this study the structure and stability of all non-(0001) low-index surfaces were calculated with RPBE-D3 and converged slab models. In all cases reconstruction involving bond formation between unsaturated carbon atoms of two neighboring graphene sheets reduces the surface energy dramatically. Two possible reconstruction patterns have been considered. The first possibility leads to formation of oblong nanotubes. Alternatively, the graphene sheets form bonds to different neighboring sheets at the upper and lower sides and sinusoidal structures are formed. Both structure types have similar stabilities. Based on the calculated surface energies the Gibbs-Wulff theorem was applied to construct the macroscopic shape of graphite single crystals.

  4. Throat swab culture

    MedlinePlus

    ... throat. It is most often used to diagnose strep throat . How the Test is Performed You will be ... done when a throat infection is suspected, particularly strep throat. A throat culture can also help your provider ...

  5. Infections and foreign bodies in ENT.

    PubMed

    Kullar, Peter; Yates, Philip D

    2012-10-30

    Infections play a major role in the practice of ENT. Microbial penetration into tissues of the head and neck can initiate a focal reaction causing superficial self-resolving infections. However, some of these have the potential to develop into life-threatening disease. We provide an overview of the most common ENT infections with focus on the presentation, diagnosis and management. Foreign bodies of the ear, nose and throat are a common presentation to primary and emergency care. Most commonly these are seen in children and include plastic toys, beads and foodstuffs inserted into the ears and nose. Diagnosis is often delayed as insertion is usually not witnessed. In exceptional cases airway foreign bodies can present as a life-threatening emergency. Removal of foreign bodies can usually be achieved by a skilled practitioner with minimal complications. Methods of removal include suction catheters, syringing, and use of instrumentation. In adults, the treatment of oesophageal food bolus obstruction may require a combination of medical and surgical intervention.

  6. Self-Passivating Lithium/Solid Electrolyte/Iodine Cells

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar; Whitcare, Jay; Narayanan, Sekharipuram; West, William

    2006-01-01

    Robust lithium/solid electrolyte/iodine electrochemical cells that offer significant advantages over commercial lithium/ iodine cells have been developed. At room temperature, these cells can be discharged at current densities 10 to 30 times those of commercial lithium/iodine cells. Moreover, from room temperature up to 80 C, the maximum discharge-current densities of these cells exceed those of all other solid-electrolyte-based cells. A cell of this type includes a metallic lithium anode in contact with a commercial flexible solid electrolyte film that, in turn, is in contact with an iodine/ graphite cathode. The solid electrolyte (the chemical composition of which has not been reported) offers the high ionic conductivity needed for high cell performance. However, the solid electrolyte exhibits an undesirable chemical reactivity to lithium that, if not mitigated, would render the solid electrolyte unsuitable for use in a lithium cell. In this cell, such mitigation is affected by the formation of a thin passivating layer of lithium iodide at the anode/electrolyte interface. Test cells of this type were fabricated from iodine/graphite cathode pellets, free-standing solid-electrolyte films, and lithium-foil anodes. The cathode mixtures were made by grinding together blends of nominally 10 weight percent graphite and 90 weight percent iodine. The cathode mixtures were then pressed into pellets at 36 kpsi (248 MPa) and inserted into coin-shaped stainless-steel cell cases that were coated with graphite paste to minimize corrosion. The solid-electrolyte film material was stamped to form circular pieces to fit in the coin cell cases, inserted in the cases, and pressed against the cathode pellets with polyethylene gaskets. Lithium-foil anodes were placed directly onto the electrolyte films. The layers described thus far were pressed and held together by stainless- steel shims, wave springs, and coin cell caps. The assembled cells were then crimped to form hermetic seals. It was found that the solid electrolyte films became discolored within seconds after they were placed in contact with the cathodes - a result of facile diffusion of iodine through the solid electrolyte material (see figure).

  7. The New Perilaryngeal Airway (CobraPLA™)1 Is as Efficient as the Laryngeal Mask Airway (LMA™)2, But Provides Better Airway Sealing Pressures

    PubMed Central

    Akça, Ozan; Wadhwa, Anupama; Sengupta, Papiya; Durrani, Jaleel; Hanni, Keith; Wenke, Mary; Yücel, Yüksel; Lenhardt, Rainer; Doufas, Anthony G.; Sessler, Daniel I.

    2006-01-01

    The Laryngeal Mask Airway (LMA) is a frequently-used efficient airway device, yet it sometimes seals poorly, thus reducing the efficacy of positive-pressure ventilation. The Perilaryngeal Airway (CobraPLA) is a novel airway device with a larger pharyngeal cuff (when inflated). We tested the hypothesis that the CobraPLA was superior to LMA with regard to insertion time and airway sealing pressure and comparable to LMA in airway adequacy and recovery characteristics. After midazolam and fentanyl, 81 ASA I-II outpatients having elective surgery were randomized to receive an LMA or CobraPLA. Anesthesia was induced with propofol (2.5 mg/kg, IV), and the airway inserted. We measured 1) insertion time; 2) adequacy of the airway (no leak at 15-cm-H2O peak pressure or tidal volume of 5 ml/kg); 3) airway sealing pressure; 4) number of repositioning attempts; and 5) sealing quality (no leak at tidal volume of 8 ml/kg). At the end of surgery, gastric insufflation, postoperative sore throat, dysphonia, and dysphagia were evaluated. Data were compared with unpaired t-tests, chi-square tests, or Fisher’s Exact tests; P<0.05 was significant. Patient characteristics, insertion times, airway adequacy, number of repositioning attempts, and recovery were similar in each group. Airway sealing pressure was significantly greater with CobraPLA (23±6 cm H2O) than LMA (18±5 cm H2O, P<0.001). The CobraPLA has insertion characteristics similar to LMA, but better airway sealing capabilities. PMID:15281543

  8. Germanium Nanowires-in-Graphite Tubes via Self-Catalyzed Synergetic Confined Growth and Shell-Splitting Enhanced Li-Storage Performance.

    PubMed

    Sun, Yong; Jin, Shuaixing; Yang, Guowei; Wang, Jing; Wang, Chengxin

    2015-04-28

    Despite the high theoretical capacity, pure Ge has various difficulties such as significant volume expansion and electron and Li(+) transfer problems, when applied as anode materials in lithium ion battery (LIB), for which the solution would finally rely on rational design like advanced structures and available hybrid. Here in this work, we report a one-step synthesis of Ge nanowires-in-graphite tubes (GNIGTs) with the liquid Ge/C synergetic confined growth method. The structure exhibits impressing LIB behavior in terms of both cyclic stability and rate performance. We found the semiclosed graphite shell with thickness of ∼50 layers experience an interesting splitting process that was driven by electrolyte diffusion, which occurs before the Ge-Li alloying plateau begins. Two types of different splitting mechanism addressed as "inside-out"/zipper effect and "outside-in" dominate this process, which are resulted from the SEI layer growing longitudinally along the Ge-graphite interface and the lateral diffusion of Li(+) across the shell, respectively. The former mechanism is the predominant way driving the initial shell to split, which behaves like a zipper with SEI layer as invisible puller. After repeated Li(+) insertion/exaction, the GNIGTs configuration is finally reconstructed by forming Ge nanowires-thin graphite strip hybrid, both of which are in close contact, resulting in enormous enchantment to the electrons/Li(+) transport. These features make the structures perform well as anode material in LIB. We believe both the progress in 1D assembly and the structure evolution of this Ge-C composite would contribute to the design of advanced LIB anode materials.

  9. Solid sampling determination of magnesium in lithium niobate crystals by graphite furnace atomic absorption spectrometry

    NASA Astrophysics Data System (ADS)

    Dravecz, Gabriella; Laczai, Nikoletta; Hajdara, Ivett; Bencs, László

    2016-12-01

    The vaporization/atomization processes of Mg in high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS-GFAAS) were investigated by evaporating solid (powder) samples of lithium niobate (LiNbO3) optical single crystals doped with various amounts of Mg in a transversally heated graphite atomizer (THGA). Optimal analytical conditions were attained by using the Mg I 215.4353 nm secondary spectral line. An optimal pyrolysis temperature of 1500 °C was found for Mg, while the compromise atomization temperature in THGAs (2400 °C) was applied for analyte vaporization. The calibration was performed against solid (powered) lithium niobate crystal standards. The standards were prepared with exactly known Mg content via solid state fusion of the oxide components of the matrix and analyte. The correlation coefficient (R value) of the linear calibration was not worse than 0.9992. The calibration curves were linear in the dopant concentration range of interest (0.74-7.25 mg/g Mg), when dosing 3-10 mg of the powder samples into the graphite sample insertion boats. The Mg content of the studied 19 samples was in the range of 1.69-4.13 mg/g. The precision of the method was better than 6.3%. The accuracy of the results was verified by means of flame atomic absorption spectrometry with solution sample introduction after digestion of several crystal samples.

  10. Resistivity of Carbon-Carbon Composites Halved

    NASA Technical Reports Server (NTRS)

    Gaier, James R.

    2004-01-01

    Carbon-carbon composites have become the material of choice for applications requiring strength and stiffness at very high temperatures (above 2000 C). These composites comprise carbon or graphite fibers embedded in a carbonized or graphitized matrix. In some applications, such as shielding sensitive electronics in very high temperature environments, the performance of these materials would be improved by lowering their electrical resistivity. One method to lower the resistivity of the composites is to lower the resistivity of the graphite fibers, and a proven method to accomplish that is intercalation. Intercalation is the insertion of guest atoms or molecules into a host lattice. In this study the host fibers were highly graphitic pitch-based graphite fibers, or vapor-grown carbon fibers (VGCF), and the intercalate was bromine. Intercalation compounds of graphite are generally thought of as being only metastable, but it has been shown that the residual bromine graphite fiber intercalation compound is remarkably stable, resisting decomposition even at temperatures at least as high as 1000 C. The focus of this work was to fabricate composite preforms, determine whether the fibers they were made from were still intercalated with bromine after processing, and determine the effect on composite resistivity. It was not expected that the resistivity would be lowered as dramatically as with graphite polymer composites because the matrix itself would be much more conductive, but it was hoped that the gains would be substantial enough to warrant its use in high-performance applications. In a collaborative effort supporting a Space Act Agreement between the NASA Glenn Research Center and Applied Sciences, Inc. (Cedarville, OH), laminar preforms were fabricated with pristine and bromine-intercalated pitch-based fibers (P100 and P100-Br) and VGCF (Pyro I and Pyro I-Br). The green preforms were carbonized at 1000 C and then heat treated to 3000 C. To determine whether the fibers in the samples were still intercalated after composite fabrication, they were subjected to X-ray diffraction. The composites containing intercalated graphite fibers showed much higher background scatter than that of pristine fibers, indicating the presence of bromine in the samples. More importantly, faint features indicative of intercalation were visible in the diffraction pattern, showing that the fibers were still intercalated.

  11. Apparatus and method for maintaining an article at a temperature that is less than the temperature of the ambient air

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

    Klett, James; Klett, Lynn

    An apparatus for maintaining the temperature of an article at a temperature that is below the ambient air temperature includes an enclosure having an outer wall that defines an interior chamber for holding a volume of sealed air. An insert is disposed inside of the chamber and has a body that is made of a porous graphite foam material. A vacuum pump penetrates the outer wall and fluidly connects the sealed air in the interior chamber with the ambient air outside of the enclosure. The temperatures of the insert and article is maintained at temperatures that are below the ambientmore » air temperature when a volume of a liquid is wicked into the pores of the porous insert and the vacuum pump is activated to reduce the pressure of a volume of sealed air within the interior chamber to a pressure that is below the vapor pressure of the liquid.« less

  12. Schnellverfahren zur flammenlosen AAS-Bestimmung von Spurenelementen in geologischen Proben

    NASA Astrophysics Data System (ADS)

    Schrön, W.; Bombach, G.; Beuge, P.

    This paper reports experience with direct quantitative trace element determinations in powdered geological samples by nameless atomic absorption spectroscopy. Two methods were explored. The first one is based on the production of a sample aerosol by laser radiation in a specifically designed sample chamber and the subsequent transport of the aerosol into a graphite tube, which has been preheated to a stable temperature. This technique is suited for a large range of concentration and is relatively free from matrix interferences. The technique was tested for the elements Ag, As, Bi, Cd, Co, Mn, Ni, Pb, Sb, Se, Sr and Tl. The described sample chamber can be also used in combination with other spcctroscopic techniques. The second method explored permits the quantitative determination of trace elements at very low concentrations. Essentially an accurately weighed amount of sample is placed on a graphite rod and introduced into a graphite furnace by inserting the rod through the sample injection port. Atomization takes place also under stable temperature conditions. Using this technique detection limits were found to be 10 -11 g for Ag, 2 × 10 -11 g for Cd and 10 -10 g for Sb in silicate materials.

  13. Multifunctional (Nano)Composite Materials for Energy Storage: Towards Flexible Load-Bearing Batteries and Supercapacitors

    DTIC Science & Technology

    2012-08-01

    e.g. large volume changes during insertion/extraction of ions and/or low electrical and ionic conductivity)  Rational design of carbon -containing...to ~ 200 mAh/g, particularly for high power cells • If graphite is replaced with Carbon fibers or CNTs, the mechanical properties of the CNT will...rigid spherical granules Annealed carbon black (CB) 100 nm Si Magasinski, A. et. al, Nature Materials, 2010, 9, 353 • Uniformity of the

  14. Effect of Damage on Strength and Durability

    DTIC Science & Technology

    2010-05-01

    sheets and different core materials. The HRP core has a phenolic resin matrix, the NP core has nylon modified phenolic base resin matrix and TPC core...core are 25% to 65% higher than those of NP or TPC cores. The phenolic resin of the HRP makes core stiff and brittle, resulting in cracking on impact...characteristics of graphite laminates can be improved by inserting glass or Kevlar fibers to form a hybrid laminate system. However, since glass and

  15. Cold cathode vacuum discharge tube

    DOEpatents

    Boettcher, Gordon E.

    1998-01-01

    A cold cathode vacuum discharge tube, and method for making same, with an interior surface of the trigger probe coated with carbon deposited by carbon vapor deposition (CVD) or diamond-like carbon (DLC) deposition. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging.

  16. APPARATUS FOR DETECTING AND LOCATING PRESENCE OF FLUIDS

    DOEpatents

    Williamson, R.R.

    1958-09-16

    A system is described fur detecting water leaks in water-cooled neutronic reactors by utilizing an electrical hygrometer having a resistance element variable with the moisture content. The graphite blocks, forming the moderator in many types of reactors, coniain ducts in which helium gas is circulated. When a leak occurs in a coolant tube, the water will seep through the graphite until it oozes into one of the helium ducts, where it will be swept along with the helium into a system of pipes that connect each of the helium ducts. By inserting an electric hygrometer in each of these pipes and connecting it to an alarm system, the moisture content of the helium will cause a change in the electrical resistance of the hygrometer which will initiate a signal alarm indicating the presence and position of the leaky water tube in the reactor.

  17. Lightning discharge protection rod

    NASA Technical Reports Server (NTRS)

    Bryan, Charles F., Jr. (Inventor)

    1987-01-01

    A system for protecting an in-air vehicle from damage due to a lighning strike is disclosed. It is an extremely simple device consisting of a sacrificial graphite composite rod, approximately the diameter of a pencil with a length of about five inches. The sacrificial rod is constructed with the graphite fibers running axially within the rod in a manner that best provides a path of conduction axially from the trailing edge of an aircraft to the trailing end of the rod. The sacrificial rod is inserted into an attachment hole machined into trailing edges of aircraft flight surfaces, such as a vertical fin cap and attached with adhesive in a manner not prohibiting the conduction path between the rod and the aircraft. The trailing end of the rod may be tapered for aerodynamic and esthetic requirements. This rod is sacrificial but has the capability to sustain several lightning strikes and still provide protection.

  18. Compatibility of the Radio Frequency Mass Gauge with Composite Tanks

    NASA Technical Reports Server (NTRS)

    Zimmerli, Greg; Mueller, Carl

    2015-01-01

    The radio frequency mass gauge (RFMG) is a low-gravity propellant quantity gauge being developed at NASA for possible use in long-duration space missions utilizing cryogenic propellants. As part of the RFMG technology development process, we evaluated the compatibility of the RFMG with a graphite-epoxy composite material used to construct propellant tanks. The key material property that can affect compatibility with the RFMG is the electrical conductivity. Using samples of 8552IM7 graphite-epoxy composite, we characterized the resistivity and reflectivity over a range of frequencies. An RF impedance analyzer was used to characterize the out-of-plane electrical properties (along the sample thickness) in the frequency range 10 to 1800 MHZ. The resistivity value at 500 MHz was 4.8 ohm-cm. Microwave waveguide measurements of samples in the range 1.7 2.6 GHz, performed by inserting the samples into a WR-430 waveguide, showed reflectivity values above 98. Together, these results suggested that a tank constructed from graphite-epoxy composite would produce good quality electromagnetic tank modes, which is needed for the RFMG. This was verified by room-temperature measurements of the electromagnetic modes of a 2.4 m diameter tank constructed by Boeing from similar graphite-epoxy composite material. The quality factor Q of the tank electromagnetic modes, measured via RF reflection measurements from an antenna mounted in the tank, was typically in the range 400 Q 3000. The good quality modes observed in the tank indicate that the RFMG is compatible with graphite-epoxy tanks, and thus the RFMG could be used as a low-gravity propellant quantity gauge in such tanks filled with cryogenic propellants.

  19. Shoe inserts alter plantar loading and function in patients with midfoot arthritis.

    PubMed

    Rao, Smita; Baumhauer, Judith F; Becica, Laura; Nawoczenski, Deborah A

    2009-07-01

    Experimental laboratory study supplemented by a case series. (1) To assess the effect of a 4-week intervention with a full-length insert on functional outcomes in patients with midfoot arthritis; (2) to examine the effect of the custom molded three-quarter-length (3Q) and full-length (FL) carbon graphite insert on plantar loading in patients with midfoot arthritis. Given the coexistence of pain and lower-arched foot alignment in patients with midfoot arthritis, arch-restoring orthotic devices such as the 3Q insert are frequently recommended. However, patients continue to report foot pain despite using the 3Q insert. The FL insert has been proposed as an alternative, but objective data examining its efficacy are lacking. Twenty female patients with midfoot arthritis participated in the study. Functional outcomes were assessed using the Foot Function Index-Revised (FFI-R). Plantar loading during walking was measured in the following conditions: shoe only, shoe with 3Q insert, and shoe with FL insert. Repeated-measures analyses of variance with post hoc analyses were used for statistical analysis. FL insert use for 4 weeks resulted in a 12% improvement in total FFI-R score (mean +/- SD before, 35.6 +/- 10.9; after, 31.1 +/- 9.8 [P = .03]). FL insert use resulted in a 20% reduction in medial midfoot average pressure loading (mean +/- SD, 64.8 +/- 20.4 and 51.0 +/- 15.4 kPa, with 3Q and FL insert respectively [P = .015]) and an 8.5% reduction in medial midfoot contact time (mean +/- SD, 84.9% +/- 6.4% and 76.4% +/- 7.1% of stance, with 3Q and FL insert respectively [P<.01]), compared to the 3Q insert. No differences in plantar loading were discerned between the shoe-only and FL conditions. Symptomatic improvement in patients with midfoot arthritis treated with a FL insert was accompanied by reduced magnitude and duration of loading under the medial midfoot. These preliminary outcomes suggest that the FL insert may be a viable alternative in the conservative management of patients with midfoot arthritis. Therapy, level 4. J Orthop Sports Phys Ther 2009;39(7):522-531. doi:10.2519/jospt.2009.2900.

  20. ISRO's solid rocket motors

    NASA Astrophysics Data System (ADS)

    Nagappa, R.; Kurup, M. R.; Muthunayagam, A. E.

    1989-08-01

    Solid rocket motors have been the mainstay of ISRO's sounding rockets and the first generation satellite launch vehicles. For the new launch vehicle under development also, the solid rocket motors contribute significantly to the vehicle's total propulsive power. The rocket motors in use and under development have been developed for a variety of applications and range in size from 30 mm dia employing 450 g of solid propellant—employed for providing a spin to the apogee motors—to the giant 2.8 m dia motor employing nearly 130 tonnes of solid propellant. The initial development, undertaken in 1967 was of small calibre motor of 75 mm dia using a double base charge. The development was essentially to understand the technological elements. Extruded aluminium tubes were used as a rocket motor casing. The fore and aft closures were machined from aluminium rods. The grain was a seven-pointed star with an enlargement of the port at the aft end and was charged into the chamber using a polyester resin system. The nozzle was a metallic heat sink type with graphite throat insert. The motor was ignited with a black powder charge and fired for 2.0 s. Subsequent to this, further developmental activities were undertaken using PVC plastisol based propellants. A class of sounding rockets ranging from 125 to 560 mm calibre were realized. These rocket motors employed improved designs and had delivered lsp ranging from 2060 to 2256 Ns/kg. Case bonding could not be adopted due to the higher cure temperatures of the plastisol propellants but improvements were made in the grain charging techniques and in the design of the igniters and the nozzle. Ablative nozzles based on asbestos phenolic and silica phenolic with graphite inserts were used. For the larger calibre rocket motors, the lsp could be improved by metallic additives. In the early 1970s designs were evolved for larger and more efficient motors. A series of 4 motors for the country's first satellite launch vehicle SLV-3 were developed. The first and second stages of 1 and 0.8 m dia respectively used low carbon steel casing and PBAN propellant. The first stage used segmented construction with a total propellant weight of 8600 kg. The second stage employed about 3 tonnes of the same propellant. The third and fourth stages were of GFRP construction and employed respectively 1100 and 275 kg of CTPB type propellants. Nozzle expansion ratios upto 30 were employed and delivered vacuum lsp of 2766 Ns/kg realized. The fourth stage motor was subsequently used as the apogee motor for orbit injection of India's first geosynchronous satellite—APPLE. All these motors have been flight proven a number of times. Further design improvements have been incorporated and these motors continue to be in use. Starting in 1984 design for a large booster was undertaken. This booster employs a nominal propellant weight of 125 tonne in a 2.8 m dia casing. The motor is expected to be qualified for flight test in 1989. Side by side a high performance motor housing nearly 7 tonnes of propellant in composite casing of 2 m dia and having flex nozzle control system is also under development for upper stage application. Details of the development of the motors, their leading specifications and performance are described.

  1. Self-pressurized air-Q® intubating laryngeal airway versus the LMA® Classic™: a randomized clinical trial.

    PubMed

    Ha, Sang Hee; Kim, Min-Soo; Suh, Jiwoo; Lee, Jong Seok

    2018-05-01

    The self-pressurized air-Q® (air-Q SP) intubating laryngeal airway is a relatively new supraglottic airway (SGA) device. The intracuff pressure of air-Q dynamically equilibrates with the airway pressure and adjusts to the patient's pharyngeal and periglottic anatomy, potentially providing improved airway fit and seal. The aim of this prospective randomized study was to compare the clinical performance of air-Q to the LMA® Classic™ SGA. Adult patients requiring general anesthesia for elective surgery were prospectively enrolled and randomly assigned to either air-Q SP or the LMA Classic SGA. Oropharyngeal leak pressure (primary endpoint), success rate, insertion features (insertion time, ease of insertion, requirement for device manipulation), sealing function, gastric insufflation, bronchoscopic view, and oropharyngeal complications at device insertion and following its removal (sore throat, dysphagia, dysphonia) were compared. The mean (standard deviation [SD]) oropharyngeal leak pressure just after insertion was similar in the air-Q SP and LMA [16.8 (4.9) vs 18.6 (5.5) cm H 2 O, respectively; mean difference, 1.8 cm H 2 O; 95% CI, -0.5 to 4.2; P = 0.13] and did not differ at ten minutes following device insertion. Median [interquartile range (IQR)] peak inspiratory pressure just after insertion was lower in the air-Q SP (11.0 [10.0-13.0] vs 13.0 [11.0-14.0] cmH 2 O, median difference, 1.0 cm H 2 O; 95% CI, 0.0 to 2.0; P = 0.03) but no difference was observed at ten minutes. The median [IQR] insertion time was faster with the air-Q SP (15.9 [13.6-20.3] sec vs 24 [21.2-27.1] sec; median difference, 8.1 sec; 95% CI, 5.6 to 9.9; P < 0.001) and improved bronchoscopic viewing grade were seen with the air-Q SP immediately after insertion (P < 0.001). No differences between the groups were observed with respect to the rate of successful insertion at first attempt, overall insertion success rate, ease of insertion, and complications. The air-Q SP had similar leak pressures but a faster insertion time and superior bronchoscopic viewing grade when compared with the LMA Classic. The air-Q SP is a suitable alternative to the LMA Classic in adult patients and may be a superior conduit for tracheal intubation. www.clinicaltrials.gov (NCT02206438). Registered 1 August 2014.

  2. Sore Throat

    MedlinePlus

    ... and mononucleosis) can lead to a sore throat. Bacteria (such as those that cause strep throat) can ... each side of your throat) become infected by bacteria or a virus. It causes the tonsils to ...

  3. Cold cathode vacuum discharge tube

    DOEpatents

    Boettcher, G.E.

    1998-03-10

    A cold cathode vacuum discharge tube, and method for making same, are disclosed with an interior surface of the trigger probe coated with carbon deposited by carbon vapor deposition (CVD) or diamond-like carbon (DLC) deposition. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging. 15 figs.

  4. Cold cathode vacuum discharge tube

    DOEpatents

    Boettcher, G.E.

    1998-04-14

    A cold cathode vacuum discharge tube, and method for making same, with an interior surface of the trigger probe coated with carbon deposited by chemical vapor deposition (CVD) or diamond-like carbon (DLC) deposition are disclosed. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging. 14 figs.

  5. Efficacy of flurbiprofen 8.75 mg lozenge in patients with a swollen and inflamed sore throat.

    PubMed

    Aspley, Sue; Shephard, Adrian; Schachtel, Emily; Sanner, Kathleen; Savino, Laurie; Schachtel, Bernard

    2016-09-01

    Sore throat is often over-treated with antibiotics, therefore there is a need for non-antibiotic treatments that provide effective relief. From the patient's point of view, symptoms of pharyngeal inflammation such as a "swollen" and "inflamed" throat are often considered the most bothersome; so, a non-steroidal anti-inflammatory drug could be an appropriate treatment. We investigated the efficacy and safety of flurbiprofen 8.75 mg lozenge in adults with a swollen and inflamed throat. We enrolled adults with moderate-to-severe sore throat and evidence of tonsillo-pharyngitis into a randomized, double-blind study. Patients received flurbiprofen 8.75 mg or placebo lozenges every 3-6 hours as needed (up to five lozenges in 24 hours) and rated their symptoms (sore throat pain, difficulty swallowing and the sensation of a swollen throat) on standard linear scales regularly over 24 hours. The efficacy of flurbiprofen lozenge was determined in patients reporting a swollen and inflamed throat at baseline, as well as those with relatively severe symptoms. ClinicalTrials.gov NCT01049334. The main outcome measures were the time-weighted summed differences in patient-reported sore throat pain, difficulty swallowing and swollen throat over 24 hours. Out of 204 patients, 124 (60.8%) described their throats as swollen and inflamed at baseline. Flurbiprofen lozenges provided greater relief than placebo over 24 hours: 79.8%, 99.6% and 69.3% (for sore throat pain, difficulty swallowing and swollen throat, respectively, all P ≤ 0.01). These outcomes were more substantial in patients with relatively severe symptoms. No serious or unexpected adverse events occurred. Flurbiprofen 8.75 mg lozenge appears to provide effective, well-tolerated relief of sore throat, difficulty swallowing and swollen throat in adults with a swollen and inflamed throat, as well as those with relatively severe symptoms. A limitation of these findings is that, while predetermined, these are secondary outcomes derived from a targeted sub-group of patients, not the entire study population.

  6. Throat infections are associated with exacerbation in a substantial proportion of patients with chronic plaque psoriasis

    PubMed Central

    Thorleifsdottir, Ragna H.; Eysteinsdottir, Jenna H.; Olafsson, Jon H.; Sigurdsson, Martin I.; Johnston, Andrew; Valdimarsson, Helgi; Sigurgeirsson, Bardur

    2016-01-01

    Streptococcal throat infections are known to trigger or exacerbate psoriasis, and several studies support the benefit of tonsillectomy. To evaluate the potential of tonsillectomy as a treatment, we used a retrospective study-specific questionnaire to assess the proportion of psoriasis patients with sore throat-associated psoriasis exacerbations. Our survey sampled 275 psoriasis patients. 42% of patients with plaque psoriasis reported sore throat-associated psoriasis exacerbations, and 72% of patients with confirmed streptococcal infections reported aggravation. Notably, women and early onset psoriasis patients were more likely to report psoriasis exacerbation after a sore throat (p<0.001, p=0.046 respectively). Other psoriasis aggravation factors were more common in patients with sore throat-associated exacerbations (p<0.01). 49% of tonsillectomized patients reported subsequent improvement and had more frequent sore throat-associated aggravation of psoriasis than patients who did not improve after tonsillectomy (p=0.015). These findings suggest a closer association between sore throats, streptococcal throat infections and plaque psoriasis than previously reported. PMID:26984718

  7. Throat Infections are Associated with Exacerbation in a Substantial Proportion of Patients with Chronic Plaque Psoriasis.

    PubMed

    Thorleifsdottir, Ragna H; Eysteinsdóttir, Jenna H; Olafsson, Jón H; Sigurdsson, Martin I; Johnston, Andrew; Valdimarsson, Helgi; Sigurgeirsson, Bardur

    2016-08-23

    Streptococcal throat infections are known to trigger or exacerbate psoriasis, and several studies support the benefit of tonsillectomy. To evaluate the potential of tonsillectomy as a treatment, we used a retrospective study-specific questionnaire to assess the proportion of psoriasis patients with sore throat-associated psoriasis exacerbations. Our survey sampled 275 psoriasis patients. Of patients with plaque psoriasis, 42% reported sore throat-associated psoriasis exacerbations, and of patients with confirmed streptococcal infections, 72% reported aggravation. Notably, women and patients with early onset psoriasis were more likely to report psoriasis exacerbation after a sore throat (p < 0.001, p = 0.046, respectively). Other psoriasis aggravation factors were more common in patients with sore throat-associated exacerbations (p < 0.01). Of tonsillectomized patients, 49% reported subsequent improvement and had more frequent sore throat-associated aggravation of psoriasis than patients who did not improve after tonsillectomy (p = 0.015). These findings suggest a closer association between sore throats, streptococcal throat infections and plaque psoriasis than reported previously.

  8. Flurbiprofen 8.75 mg lozenges for treating sore throat symptoms: a randomized, double-blind, placebo-controlled study.

    PubMed

    Schachtel, Bernard P; Shephard, Adrian; Shea, Timothy; Sanner, Kathleen; Savino, Laurie; Rezuke, Jeanne; Schachtel, Emily; Aspley, Sue

    2016-11-01

    This study assessed multiple doses of flurbiprofen 8.75 mg lozenges for the relief of three prominent symptoms of acute pharyngitis: pain intensity (primary end point), difficulty swallowing and swollen throat. A total of 204 patients (102 in each group) with confirmed pharyngitis (onset ≤4 days) were randomly assigned to take up to five flurbiprofen or placebo lozenges every 3-6 h, for 7 days. Using validated rating scales (sore throat pain intensity, difficulty swallowing and swollen throat) patients rated their symptoms for the duration of the study. Over the first 24 h, patients treated with flurbiprofen lozenges reported significantly greater reductions in sore throat pain (47%) as well as difficulty swallowing (66%) and swollen throat (40%) compared with placebo (all p < 0.05). Multiple doses of flurbiprofen lozenges provide effective relief of sore throat pain intensity as well as difficulty swallowing and swollen throat.

  9. The rational clinical examination. Does this patient have strep throat?

    PubMed

    Ebell, M H; Smith, M A; Barry, H C; Ives, K; Carey, M

    2000-12-13

    Sore throat is a common complaint, and identifying patients with group A beta-hemolytic streptococcal pharyngitis (strep throat) is an important task for clinicians. Previous reviews have not systematically reviewed and synthesized the evidence. To review the precision and accuracy of the clinical examination in diagnosing strep throat. MEDLINE search for articles about diagnosis of strep throat using history-taking and physical examination. Large blinded, prospective studies (having > or =300 patients with sore throat) reporting history and physical examination data and using throat culture as the reference standard were included. Of 917 articles identified by the search, 9 met all inclusion criteria. Pairs of authors independently reviewed each article and used consensus to resolve discrepancies. The most useful findings for evaluating the likelihood of strep throat are presence of tonsillar exudate, pharyngeal exudate, or exposure to strep throat infection in the previous 2 weeks (positive likelihood ratios, 3.4, 2.1, and 1.9, respectively) and the absence of tender anterior cervical nodes, tonsillar enlargement, or exudate (negative likelihood ratios, 0.60, 0.63, and 0.74, respectively). No individual element of history-taking or physical examination is accurate enough by itself to rule in or rule out strep throat. Three validated clinical prediction rules are described for adult and pediatric populations. While no single element of history-taking or physical examination is sufficiently accurate to exclude or diagnose strep throat, a well-validated clinical prediction rule can be useful and can help physicians make more informed use of rapid antigen tests and throat cultures.

  10. 3D-printed conductive static mixers enable all-vanadium redox flow battery using slurry electrodes

    NASA Astrophysics Data System (ADS)

    Percin, Korcan; Rommerskirchen, Alexandra; Sengpiel, Robert; Gendel, Youri; Wessling, Matthias

    2018-03-01

    State-of-the-art all-vanadium redox flow batteries employ porous carbonaceous materials as electrodes. The battery cells possess non-scalable fixed electrodes inserted into a cell stack. In contrast, a conductive particle network dispersed in the electrolyte, known as slurry electrode, may be beneficial for a scalable redox flow battery. In this work, slurry electrodes are successfully introduced to an all-vanadium redox flow battery. Activated carbon and graphite powder particles are dispersed up to 20 wt% in the vanadium electrolyte and charge-discharge behavior is inspected via polarization studies. Graphite powder slurry is superior over activated carbon with a polarization behavior closer to the standard graphite felt electrodes. 3D-printed conductive static mixers introduced to the slurry channel improve the charge transfer via intensified slurry mixing and increased surface area. Consequently, a significant increase in the coulombic efficiency up to 95% and energy efficiency up to 65% is obtained. Our results show that slurry electrodes supported by conductive static mixers can be competitive to state-of-the-art electrodes yielding an additional degree of freedom in battery design. Research into carbon properties (particle size, internal surface area, pore size distribution) tailored to the electrolyte system and optimization of the mixer geometry may yield even better battery properties.

  11. Structure of the effective potential for a spherical wormhole

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

    Montelongo Garcia, N.; Zannias, T.

    2008-09-15

    The structure of the effective potential V describing causal geodesics near the throat of an arbitrary spherical wormhole is analyzed. Einstein's equations relative to a set of regular coordinates covering a vicinity of the throat imply that any spherical wormhole can be constructed from solutions of an effective initial value problem with the throat serving as an initial value surface. The initial data involve matter variables, the area A(0) of the throat, and the gradient {lambda}(0) of the redshift factor on the throat. Whenever {lambda}(0)=0, the effective potential V has a critical point on the throat. Conditions upon the datamore » are derived ensuring that the critical point is a local minimum (respectively maximum). For particular families of quasi-Schwarzschild wormholes, V exhibits a local minimum on the throat independently upon the energy E and angular momentum L{sup 2} of the test particles and thus such wormholes admit stable circular timelike and null geodesics on the throat. For families of Chaplygin wormholes, we show that such geodesics are unstable. Based on a suitable power series representation of the metric, properties of V away from the throat are obtained that are useful for the analysis of accretion disks and radiation processes near the throat of any spherical wormhole.« less

  12. Utility of the sore throat pain model in a multiple-dose assessment of the acute analgesic flurbiprofen: a randomized controlled study.

    PubMed

    Schachtel, Bernard; Aspley, Sue; Shephard, Adrian; Shea, Timothy; Smith, Gary; Schachtel, Emily

    2014-07-03

    The sore throat pain model has been conducted by different clinical investigators to demonstrate the efficacy of acute analgesic drugs in single-dose randomized clinical trials. The model used here was designed to study the multiple-dose safety and efficacy of lozenges containing flurbiprofen at 8.75 mg. Adults (n=198) with moderate or severe acute sore throat and findings of pharyngitis on a Tonsillo-Pharyngitis Assessment (TPA) were randomly assigned to use either flurbiprofen 8.75 mg lozenges (n=101) or matching placebo lozenges (n=97) under double-blind conditions. Patients sucked one lozenge every three to six hours as needed, up to five lozenges per day, and rated symptoms on 100-mm scales: the Sore Throat Pain Intensity Scale (STPIS), the Difficulty Swallowing Scale (DSS), and the Swollen Throat Scale (SwoTS). Reductions in pain (lasting for three hours) and in difficulty swallowing and throat swelling (for four hours) were observed after a single dose of the flurbiprofen 8.75 mg lozenge (P<0.05 compared with placebo). After using multiple doses over 24 hours, flurbiprofen-treated patients experienced a 59% greater reduction in throat pain, 45% less difficulty swallowing, and 44% less throat swelling than placebo-treated patients (all P<0.01). There were no serious adverse events. Utilizing the sore throat pain model with multiple doses over 24 hours, flurbiprofen 8.75 mg lozenges were shown to be an effective, well-tolerated treatment for sore throat pain. Other pharmacologic actions (reduced difficulty swallowing and reduced throat swelling) and overall patient satisfaction from the flurbiprofen lozenges were also demonstrated in this multiple-dose implementation of the sore throat pain model. This trial was registered with ClinicalTrials.gov, registration number: NCT01048866, registration date: January 13, 2010.

  13. De-agglomeration Effect of the US Pharmacopeia and Alberta Throats on Carrier-Based Powders in Commercial Inhalation Products.

    PubMed

    Leung, Sharon Shui Yee; Tang, Patricia; Zhou, Qi Tony; Tong, Zhenbo; Leung, Cassandra; Decharaksa, Janwit; Yang, Runyu; Chan, Hak-Kim

    2015-11-01

    The US pharmacopeia (USP) and Alberta throats were recently reported to cause further de-agglomeration of carrier-free powders emitted from some dry powder inhalers (DPIs). This study assessed if they have similar influences on commercially available carrier-based DPIs. A straight tube, a USP throat, and an Alberta throat (non-coated and coated) were used for cascade impaction testing. Aerosol fine particle fraction (FPF ≤ 5 μm) was computed to evaluate throat-induced de-agglomeration. Computational fluid dynamics are employed to simulate airflow patterns and particle trajectories inside the USP and Alberta throats. For all tested products, no significant differences in the in vitro aerosol performance were observed between the USP throat and the straight tube. Using fine lactose carriers (<10 μm), Symbicort(®) and Oxis(™) showed minimal impaction inside the Alberta throat and resulted in similar FPF among all induction ports. For products using coarse lactose carriers (>10 μm), impaction frequency and energy inside the Alberta throat were significant. Further de-agglomeration was noted inside the non-coated Alberta throat for Seretide(®) and Spiriva(®), but agglomerates emitted from Relenza(®), Ventolin(®), and Foradil(®) did not further break up into smaller fractions. The coated Alberta throat considerably reduced the FPF values of these products due to the high throat retention, but they generally agreed better with the in vivo data. In conclusion, depending on the powder formulation (including carrier particle size), the inhaler, and the induction port, further de-agglomeration could happen ex-inhaler and create differences in the in vitro measurements.

  14. 'Black universe' epoch in string cosmology

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

    Buchel, Alex; Perimeter Institute for Theoretical Physics, Waterloo, Ontario, N2J 2W9; Kofman, Lev

    2008-10-15

    String theory compactification involves manifolds with multiple warp factors. For cosmological applications, we often introduce a short, high-energy inflationary throat, and a long, low-energy standard model (SM) throat. It is assumed that at the end of inflation, the excited Kaluza-Klein modes from the inflationary throat tunnel to the SM throat and reheat standard model degrees of freedom, which are attached to probe brane(s). However, the huge hierarchy of energy scales can result in a highly dynamic transition of the throat geometry. We point out that in such a cosmological scenario the standard model throat (together with SM brane) will bemore » cloaked by a Schwarzschild horizon, produced by the Kaluza-Klein modes tunneling from the short throat. The black brane formation is dual to the first order chiral phase transition of the cascading gauge theory. We calculate the critical energy density corresponding the formation of the black hole (BH) horizon in the long throat. We discuss the duality between 'black universe' cosmology and an expanding universe driven by the hot gauge theory radiation. We address the new problem of the hierarchical multiple-throat scenarios: SM brane disappearance after the decay of the BH horizon.« less

  15. Comparison of postoperative complication between Laryngeal Mask Airway and endotracheal tube during low-flow anesthesia with controlled ventilation

    PubMed Central

    Peirovifar, Ali; Eydi, Mahmood; Mirinejhad, Mir Mousa; Mahmoodpoor, Ata; Mohammadi, Afsaneh; EJ Golzari, Samad

    2013-01-01

    Objective: To compare the postoperative complications between Laryngeal Mask Airway (LMA) and endotracheal tube (ETT) during low-flow anesthesia with controlled ventilation. Methodology: Eighty adult Patients with ASA class I or II were randomly allocated into two forty-patient groups (ETT or LMA). Cuff pressure was monitored during anesthesia. After high uptake period, fresh gas flow (FGF) was decreased to 1 lit/min and isoflurane set to 1%. Monitoring during anesthesia included non-invasive blood pressure, ECG, ETCO2 and pulse oximetry. System leakage (>100 ml/min), rebreathing and any attempt to increase FGF to overcome the leak were monitored during anesthesia. Later, patients were extubated and transferred to Post Anesthesia Care Unit (PACU). In PACU, the incidence of sore throat, cough, difficulty in swallowing and shivering was monitored for all patients. Results: Leakage was observed in two and three cases in ETT and LMA groups respectively (P>0.05). Postoperative cough, sore throat and difficulty in swallowing were significantly less in LMA than ETT group. No significant difference was observed regarding ETCo2 values between 2 groups. Conclusion: If careful measures regarding insertion techniques, correct LMA position and routine monitoring of LMA cuff pressure are taken, LMA can be used as a safe alternative with lower incidence of post operation complication compared with ETT during low-flow controlled anesthesia with modern anesthetic machines. PMID:24353586

  16. An inexpensive method for quantifying incubation patterns of open-cup nesting birds, with data for black-throated Blue warblers

    USGS Publications Warehouse

    Joyce, Elizabeth M.; Sillett, T. Scott; Holmes, Richard T.

    2001-01-01

    Quantifying incubation patterns has often involved long observation periods in the field, video cameras, or the use of other electronic devices that sometimes require the partial destruction of clutches and insertion of artificial eggs. In this study, we used an inexpensive, nondestructive method involving temperature probes combined with data loggers to examine the incubation rhythm of female Black-throated Blue Warblers (Dendroica caerulescens). The method provided detailed records of on–off patterns for females for selected 24-h periods during incubation. Female warblers spent an average (±SE) of 64.0% of daylight hours incubating in bouts lasting 20.5 ± 1.5 min and made 2.4 ± 0.1 departures from the nest/h on trips that lasted 10.6 ± 0.7 min. Incubation bouts were longer and females spent more time incubating per hour in the mornings and late afternoons than at mid-day. Older females had longer incubation bouts and tended to have shorter incubation periods than did yearling females, suggesting that experienced individuals were more effective incubators. Because of its ease of use and because nests with probes were not depredated at a higher rate than controls, we suggest that the temperature probe/data logger method is an efficient and effective way to quantify incubation rhythms for open-cup nesting birds.

  17. Throat Swabs and Sputum Culture as Predictors of P. aeruginosa or S. aureus Lung Colonization in Adult Cystic Fibrosis Patients.

    PubMed

    Seidler, Darius; Griffin, Mary; Nymon, Amanda; Koeppen, Katja; Ashare, Alix

    2016-01-01

    Due to frequent infections in cystic fibrosis (CF) patients, repeated respiratory cultures are obtained to inform treatment. When patients are unable to expectorate sputum, clinicians obtain throat swabs as a surrogate for lower respiratory cultures. There is no clear data in adult subjects demonstrating the adequacy of throat swabs as a surrogate for sputum or BAL. Our study was designed to determine the utility of throat swabs in identifying lung colonization with common organisms in adults with CF. Adult CF subjects (n = 20) underwent bronchoscopy with BAL. Prior to bronchoscopy, a throat swab was obtained. A sputum sample was obtained from subjects who were able to spontaneously expectorate. All samples were sent for standard microbiology culture. Using BAL as the gold standard, we found the positive predictive value for Pseudomonas aeruginosa to be 100% in both sputum and throat swab compared to BAL. However, the negative predictive value for P. aeruginosa was 60% and 50% in sputum and throat swab, respectively. Conversely, the positive predictive value for Staphylococcus aureus was 57% in sputum and only 41% in throat swab and the negative predictive value of S. aureus was 100% in sputum and throat swab compared to BAL. Our data show that positive sputum and throat culture findings of P. aeruginosa reflect results found on BAL fluid analysis, suggesting these are reasonable surrogates to determine lung colonization with P. aeruginosa. However, sputum and throat culture findings of S. aureus do not appear to reflect S. aureus colonization of the lung.

  18. Flurbiprofen microgranules for relief of sore throat: a randomised, double-blind trial

    PubMed Central

    Russo, Marc; Bloch, Mark; de Looze, Fred; Morris, Christopher; Shephard, Adrian

    2013-01-01

    Background Many people with sore throat seek, and are often inappropriately prescribed, antibiotics. Aim The objective of this study was to determine the analgesic efficacy of flurbiprofen 8.75 mg microgranules versus placebo. These microgranules are a possible alternative treatment for patients with sore throat due to upper respiratory tract infection (URTI). Design and setting Randomised, double-blind, placebo-controlled, multiple-dose study conducted at eight primary care sites in Australia. Method Participants with sore throat of onset within the past 4 days received either flurbiprofen 8.75 mg microgranules or non-medicated placebo microgranules. Throat soreness, difficulty in swallowing, sore throat pain intensity, sore throat relief, oral temperature, and treatment benefits were all assessed at regular intervals. Result Of 373 patients from eight centres, 186 received flurbiprofen 8.75 mg microgranules and 187 received placebo microgranules (intent-to-treat population). Throat soreness was significantly reduced over the first 2 hours after the first dose. Reductions in difficulty in swallowing were observed at all time points from 5 to 360 minutes after the first dose, after taking flurbiprofen microgranules versus placebo. Sore throat relief was also evident at 1 minute and lasted for at least 6 hours. The multiple-dose efficacy results showed reduction of difficulty in swallowing at the end of days 1–3 and sore throat relief at the end of day 1. Conclusion Microgranules containing flurbiprofen 8.75 mg provided fast and effective relief from sore throat due to URTI and represent an alternative treatment option to antibiotic therapy. PMID:23561694

  19. Development of a Scanning Microscale Fast Neutron Irradiation Platform for Examining the Correlation Between Local Neutron Damage and Graphite Microstructure

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

    Pinhero, Patrick; Windes, William

    2015-03-10

    The fast particle radiation damage effect of graphite, a main material in current and future nuclear reactors, has significant influence on the utilization of this material in fission and fusion plants. Atoms on graphite crystals can be easily replaced or dislocated by fast protons and result in interstitials and vacancies. The currently accepted model indicates that after most of the interstitials recombine with vacancies, surviving interstitials form clusters and furthermore gather to create loops with each other between layers. Meanwhile, surviving vacancies and interstitials form dislocation loops on the layers. The growth of these inserted layers cause the dimensional increase,more » i.e. swelling, of graphite. Interstitial and vacancy dislocation loops have been reported and they can easily been observed by electron microscope. However, observation of the intermediate atom clusters becomes is paramount in helping prove this model. We utilize fast protons generated from the University of Missouri Research Reactor (MURR) cyclotron to irradiate highly- oriented pyrolytic graphite (HOPG) as target for this research. Post-irradiation examination (PIE) of dosed targets with high-resolution transmission electron microscopy (HRTEM) has permit observation and analysis of clusters and dislocation loops to support the proposed theory. Another part of the research is to validate M.I. Heggie’s Ruck and Tuck model, which introduced graphite layers may fold under fast particle irradiation. Again, we employed microscopy to image irradiated specimens to determine how the extent of Ruck and Tuck by calculating the number of folds as a function of dose. Our most significant accomplishment is the invention of a novel class of high-intensity pure beta-emitters for long-term lightweight batteries. We have filed four invention disclosure records based on the research conducted in this project. These batteries are lightweight because they consist of carbon and tritium and can be fabricated to conform to many geometric shapes. In addition, we have published eight peer-reviewed American Nuclear Society (ANS) transactions, and presented our findings at ANS National Meetings, and several universities.« less

  20. Improved switching reliability achieved in HfOx based RRAM with mountain-like surface-graphited carbon layer

    NASA Astrophysics Data System (ADS)

    Tao, Ye; Ding, Wentao; Wang, Zhongqiang; Xu, Haiyang; Zhao, Xiaoning; Li, Xuhong; Liu, Weizhen; Ma, Jiangang; Liu, Yichun

    2018-05-01

    In this work, we demonstrated an effective method to improve the switching reliability of HfOx based RRAM device by inserting mountain-like surface-graphited carbon (MSGC) layer. The MSGC layer was fabricated through thermal annealing of amorphous carbon (a-C) film with high sp2 proportion (49.7%) under 500 °C on Pt substrate, whose characteristics were validated by XPS and Raman spectrums. The local electric-field (LEF) was enhanced around the nanoscale tips of MSGC layer due to large surface curvature, which leads to simplified CFs and localization of resistive switching region. It takes responsibility to the reduction of high/low resistance states (HRS/LRS) fluctuation from 173.8%/64.9% to 23.6%/6.5%, respectively. In addition, the resulting RRAM devices exhibited fast switching speed (<65 ns), good retention (>104 s at 85 °C) and low cycling degradation. This method could be promising to develop reliable and repeatable high-performance RRAM for practical applications.

  1. Continuous Ultra-Thin MOS2 Films Grown by Low-Temperature Physical Vapor Deposition (Postprint)

    DTIC Science & Technology

    2014-07-01

    MoS2 target of 99.95% purity. The SiO2 and highly oriented pyrolitic graphite (HOPG) substrates were intro- duced via a vacuum load- lock and mounted on...im- mediately prior insertion into a sample vacuum load- lock . In this work, the samples were heated to 350 C and allowed to rotate at approximately...136805 (2010). 6H. Terrones, F. Lopez-Urias, and M. Terrones, Sci. Rep. 3(203), 1549 (2013). 7H. Li, Q. Zhang, C. C. R. Yap, B. K. Tay, T. H. T. Edwin

  2. Comparison between Indirect Immunofluorescence Assay and Shell Vial Culture for Detection of Mumps Virus from Clinical Samples

    PubMed Central

    Reina, Jordi; Ballesteros, Francisca; Ruiz de Gopegui, Enrique; Munar, Maria; Mari, Margarita

    2003-01-01

    We report a prospective comparison of the efficacies of an indirect immunofluorescence assay (IFA) and shell vial culture (SVC) of throat swab and urine samples from patients with mumps. Throat swab samples were used for the IFA; the urine samples and throat swabs were inoculated into vials of Vero cells. We studied 62 patients by using 62 throat swabs and 50 urine samples (50 patients with both samples). Sixty (96.7%) throat samples were positive in the SVC, and 61 (98.3%) were positive in the IFA. For the 50 patients from whom both samples were available, the IFA was positive in 50 (100%) cases, the urine sample was positive in 49 (98%) cases, and the throat swab was positive in 48 (96%) cases (P > 0.05). This comparison of throat swabs and urine samples has shown that the two clinical samples are similar in efficacy. PMID:14605158

  3. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat synthetic polymer material. 874.3620 Section 874.3620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN..., and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic polymer...

  4. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat synthetic polymer material. 874.3620 Section 874.3620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN..., and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic polymer...

  5. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat synthetic polymer material. 874.3620 Section 874.3620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN..., and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic polymer...

  6. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat synthetic polymer material. 874.3620 Section 874.3620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN..., and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic polymer...

  7. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat synthetic polymer material. 874.3620 Section 874.3620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN..., and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic polymer...

  8. Throat swabs have no influence on the management of patients with sore throats.

    PubMed

    Cheung, L; Pattni, V; Peacock, P; Sood, S; Gupta, D

    2017-11-01

    Throat swabs are neither specific nor sensitive for micro-bacteria causing sore throat symptoms; however, current guidelines suggest they are still useful in some cases. Retrospective and prospective analyses were conducted of throat swabs requested within the months of January 2016 and August 2016, respectively. The study comprised 247 patients. Fifty-nine (24 per cent) had a positive culture. Forty-six grew group A beta-haemolytic streptococci, with the remainder growing candida (n = 10), coliform (n = 1) and klebsiella (n = 2). There was no significant difference in culture rates between primary or secondary care sources (χ2 = 0.56, p = 0.45). None of the swabs influenced a variation in patient management from local antimicrobial policies. Current practice has an estimated annual financial impact of £3 434 340 on the National Health Service. Throat swabs do not influence the antimicrobial treatment for patients with sore throats, even under current guidelines, and incur unnecessary cost. Current clinical guidelines could be reviewed to reduce the number of throat swabs being conducted unnecessarily.

  9. Real-time monitoring of subsurface microbial metabolism with graphite electrodes

    DOE PAGES

    Wardman, Colin; Nevin, Kelly P.; Lovley, Derek R.

    2014-11-21

    Monitoring in situ microbial activity in anoxic submerged soils and aquatic sediments can be labor intensive and technically difficult, especially in dynamic environments in which a record of changes in microbial activity over time is desired. Microbial fuel cell concepts have previously been adapted to detect changes in the availability of relatively high concentrations of organic compounds in waste water but, in most soils and sediments, rates of microbial activity are not linked to the concentrations of labile substrates, but rather to the turnover rates of the substrate pools with steady state concentrations in the nM-μ M range. In ordermore » to determine whether levels of current produced at a graphite anode would correspond to the rates of microbial metabolism in anoxic sediments, small graphite anodes were inserted in sediment cores and connected to graphite brush cathodes in the overlying water. Currents produced were compared with the rates of [2- 14C]-acetate metabolism. There was a direct correlation between current production and the rate that [2- 14C]-acetate was metabolized to 14CO 2 and 14CH 4 in sediments in which Fe(III) reduction, sulfate reduction, or methane production was the predominant terminal electron-accepting process. At comparable acetate turnover rates, currents were higher in the sediments in which sulfate-reduction or Fe(III) reduction predominated than in methanogenic sediments. This was attributed to reduced products (Fe(II), sulfide) produced at distance from the anode contributing to current production in addition to the current that was produced from microbial oxidation of organic substrates with electron transfer to the anode surface in all three sediment types. In conclusion, the results demonstrate that inexpensive graphite electrodes may provide a simple strategy for real-time monitoring of microbial activity in a diversity of anoxic soils and sediments.« less

  10. Highly Conducting Graphite Epoxy Composite Demonstrated

    NASA Technical Reports Server (NTRS)

    Gaier, James R.

    1999-01-01

    Weight savings as high as 80 percent could be achieved if graphite polymer composites could replace aluminum in structures such as electromagnetic interference shielding covers and grounding planes. This could result in significant cost savings, especially for the mobile electronics found in spacecraft, aircraft, automobiles, and hand-held consumer electronics. However, such composites had not yet been fabricated with conductivity sufficient to enable these applications. To address this lack, a partnership of the NASA Lewis Research Center, Manchester College, and Applied Sciences, Inc., fabricated nonmetallic composites with unprecedented electrical conductivity. For these composites, heat-treated, vapor-grown graphite fibers were selected which have a resistivity of about 80 mW-cm, more than 20 times more conductive than typical carbon fibers. These fibers were then intercalated with iodine bromide (IBr). Intercalation is the insertion of guest atoms or molecules between the carbon planes of the graphite fibers. Since the carbon planes are not highly distorted in the process, intercalation has little effect on mechanical and thermal properties. Intercalation does, however, lower the carbon fiber resistivity to less than 10 mW-cm, which is comparable to that of metal fibers. Scaleup of the reaction was required since the initial intercalation experiments would be carried out on 20-mg quantities of fibers, and tens of grams of intercalated fibers would be needed to fabricate even small demonstration composites. The reaction was first optimized through a time and temperature study that yielded fibers with a resistivity of 8.7 2 mW-cm when exposed to IBr vapor at 114 C for 24 hours. Stability studies indicated that the intercalated fibers rapidly lost their conductivity when exposed to temperatures as low as 40 C in air. They were not, however, susceptible to degradation by water vapor in the manner of most graphite intercalation compounds. The 1000-fold scaleup experiments concluded that 114 C was near the optimum temperature, but that the intercalation time needed to be lengthened by a factor of 3.

  11. Passive Rocket Diffuser Theory: A Re-Examination of Minimum Second Throat Size

    NASA Technical Reports Server (NTRS)

    Jones, Daniel R.

    2016-01-01

    Second-throat diffusers serve to isolate rocket engines from the effects of ambient back pressure during testing without using active control systems. Among the most critical design parameters is the relative area of the diffuser throat to that of the nozzle throat. A smaller second throat is generally desirable because it decreases the stagnation-to-ambient pressure ratio the diffuser requires for nominal operation. There is a limit, however. Below a certain size, the second throat can cause pressure buildup within the diffuser and prevent it from reaching the start condition that protects the nozzle from side-load damage. This paper presents a method for improved estimation of the minimum second throat area which enables diffuser start. The new 3-zone model uses traditional quasi-one-dimensional compressible flow theory to approximate the structure of two distinct diffuser flow fields observed in Computational Fluid Dynamics (CFD) simulations and combines them to provide a less-conservative estimate of the second throat size limit. It is unique among second throat sizing methods in that it accounts for all major conical nozzle and second throat diffuser design parameters within its limits of application. The performance of the 3-zone method is compared to the historical normal shock and force balance methods, and verified against a large number of CFD simulations at specific heat ratios of 1.4 and 1.25. Validation is left as future work, and the model is currently intended to function only as a first-order design tool.

  12. Streptococcus A in paediatric accident and emergency: are rapid streptococcal tests and clinical examination of any help?

    PubMed

    Van Limbergen, J; Kalima, P; Taheri, S; Beattie, T F

    2006-01-01

    Rapid streptococcal tests (RSTs) for streptococcal pharyngitis have made diagnosis at once simpler and more complicated. The American Academy of Pediatrics recommends that all RSTs be confirmed by a follow up throat culture unless local validation has proved the RST to be equally sensitive. To evaluate (a) RST as a single diagnostic tool, compared with RST with or without throat culture; (b) clinical diagnosis and the relative contribution of different symptoms. The study included 213 patients with clinical signs of pharyngitis. Throat swabs were analysed using Quickvue+ Strep A Test; negative RSTs were backed up by throat culture. Thirteen clinical features commonly associated with strep throat were analysed using backward stepwise logistic regression. Positive results (RST or throat culture) were obtained in 33 patients; RST correctly identified 21. Eleven samples were false negative on RST. At a strep throat prevalence of 15.9%, sensitivity of RST was 65.6% (95% CI 46.8% to 81.4%) and specificity 99.4% (96.7% to 99.9%). Sensitivity of clinical diagnosis alone was 57% (34% to 78%) and specificity 71% (61% to 80%). Clinically, only history of sore throat, rash, and pyrexia contributed to the diagnosis of strep throat (p<0.05). The high specificity of RST facilitates early diagnosis of strep throat. However, the low sensitivity of RST does not support its use as a single diagnostic tool. The sensitivity in the present study is markedly different from that reported by the manufacturer. Clinical examination is of limited value in the diagnosis of strep throat. It is important to audit the performance of new diagnostic tests, previously validated in different settings.

  13. Streptococcus A in paediatric accident and emergency: are rapid streptococcal tests and clinical examination of any help?

    PubMed Central

    Van Limbergen, J; Kalima, P; Taheri, S; Beattie, T F

    2006-01-01

    Background Rapid streptococcal tests (RSTs) for streptococcal pharyngitis have made diagnosis at once simpler and more complicated. The American Academy of Pediatrics recommends that all RSTs be confirmed by a follow up throat culture unless local validation has proved the RST to be equally sensitive. Aims To evaluate (a) RST as a single diagnostic tool, compared with RST with or without throat culture; (b) clinical diagnosis and the relative contribution of different symptoms. Methods The study included 213 patients with clinical signs of pharyngitis. Throat swabs were analysed using Quickvue+ Strep A Test; negative RSTs were backed up by throat culture. Thirteen clinical features commonly associated with strep throat were analysed using backward stepwise logistic regression. Results Positive results (RST or throat culture) were obtained in 33 patients; RST correctly identified 21. Eleven samples were false negative on RST. At a strep throat prevalence of 15.9%, sensitivity of RST was 65.6% (95% CI 46.8% to 81.4%) and specificity 99.4% (96.7% to 99.9%). Sensitivity of clinical diagnosis alone was 57% (34% to 78%) and specificity 71% (61% to 80%). Clinically, only history of sore throat, rash, and pyrexia contributed to the diagnosis of strep throat (p<0.05). Conclusion The high specificity of RST facilitates early diagnosis of strep throat. However, the low sensitivity of RST does not support its use as a single diagnostic tool. The sensitivity in the present study is markedly different from that reported by the manufacturer. Clinical examination is of limited value in the diagnosis of strep throat. It is important to audit the performance of new diagnostic tests, previously validated in different settings. PMID:16373800

  14. Effects of different types of pharyngeal packing in patients undergoing nasal surgery: A comparative study.

    PubMed

    Rizvi, Mohd Meesam; Singh, Raj Bahadur; Rasheed, Mohd Asim; Sarkar, Arindam

    2015-01-01

    Postoperative throat complaints such as postoperative sore throat (POST), dysphagia, and hoarseness frequently arises after tracheal intubation and throat packing for patient undergoing general anesthesia. This condition is very disturbing to patient. Avoiding POST is a major priority for these patients because preventing postoperative complications contributes to patient satisfaction. To describe and analyze the postoperative throat effects of nasopharyngeal packing and oropharyngeal packing in patients undergoing nasal surgery. A randomized comparative study. After obtaining approval of Ethical Committee 40 patients were included in study. After this patient were randomly allocated into two groups of 20 each. Group A - in which the oropharynx was packed and Group B - inwhich the nasopharynx was packed. General anesthesia were given and throat packing was done and patients were interviewed postoperatively for any throat complications such as sore throat, difficulty in swallowing (dysphagia), hoarseness of voice, throat irritation, and any other symptom pertaining to the study were noted and data were analyzed. T-test to compare the age, while Chi-square test and Fisher's exact test were used to compare sex distribution, sore throat, dysphagia, hoarseness, and throat irritation. Results showed statistically significant difference in incidence and severity of POST in Group A patients when compared to Group B patients to be more. Patients in Group A had a higher incidence of dysphagia when compared to their Group B counterparts. With respect to the incidence of hoarseness and throat irritation, there was no statistical significance between the groups. We concluded that the site of pharyngeal packing influences the incidence and severity of POST and as well as the incidence of dysphagia after general anesthesia. The use of nasopharyngeal packing in the patients undergoing nasal surgeries might lead to a reduction of the same.

  15. Influence of throat configuration and fish density on escapement of channel catfish from hoop nets

    USGS Publications Warehouse

    Porath, Mark T.; Pape, Larry D.; Richters, Lindsey K.

    2011-01-01

    In recent years, several state agencies have adopted the use of baited, tandemset hoop nets to assess lentic channel catfish Ictalurus punctatus populations. Some level of escapement from the net is expected because an opening exists in each throat of the net, although factors influencing rates of escapement from hoop nets have not been quantified. We conducted experiments to quantify rates of escapement and to determine the influence of throat configuration and fish density within the net on escapement rates. An initial experiment to determine the rate of escapement from each net compartment utilized individually tagged channel catfish placed within the entrance (between the two throats) and cod (within the second throat) compartments of a single hoop net for overnight sets. From this experiment, the mean rate (±SE) of channel catfish escaping was 4.2% (±1.5) from the cod (cod throat was additionally restricted from the traditionally manufactured product), and 74% (±4.2) from the entrance compartments. In a subsequent experiment, channel catfish were placed only in the cod compartment with different throat configurations (restricted or unrestricted) and at two densities (low [6 fish per net] and high [60 fish per net]) for overnight sets to determine the influence of fish density and throat configuration on escapement rates. Escapement rates between throat configurations were doubled at low fish density (13.3 ± 5.4% restricted versus 26.7 ± 5.6% unrestricted) and tripled at high fish density (14.3 ± 4.9% restricted versus 51.9 ± 5.0% unrestricted). These results suggest that retention efficiency is high from cod compartments with restricted throat entrances. However, managers and researchers need to be aware that modification to the cod throats (restrictions) is needed for hoop nets ordered from manufacturers. Managers need to be consistent in their use and reporting of cod end throat configurations when using this gear.

  16. Utility of the sore throat pain model in a multiple-dose assessment of the acute analgesic flurbiprofen: a randomized controlled study

    PubMed Central

    2014-01-01

    Background The sore throat pain model has been conducted by different clinical investigators to demonstrate the efficacy of acute analgesic drugs in single-dose randomized clinical trials. The model used here was designed to study the multiple-dose safety and efficacy of lozenges containing flurbiprofen at 8.75 mg. Methods Adults (n = 198) with moderate or severe acute sore throat and findings of pharyngitis on a Tonsillo-Pharyngitis Assessment (TPA) were randomly assigned to use either flurbiprofen 8.75 mg lozenges (n = 101) or matching placebo lozenges (n = 97) under double-blind conditions. Patients sucked one lozenge every three to six hours as needed, up to five lozenges per day, and rated symptoms on 100-mm scales: the Sore Throat Pain Intensity Scale (STPIS), the Difficulty Swallowing Scale (DSS), and the Swollen Throat Scale (SwoTS). Results Reductions in pain (lasting for three hours) and in difficulty swallowing and throat swelling (for four hours) were observed after a single dose of the flurbiprofen 8.75 mg lozenge (P <0.05 compared with placebo). After using multiple doses over 24 hours, flurbiprofen-treated patients experienced a 59% greater reduction in throat pain, 45% less difficulty swallowing, and 44% less throat swelling than placebo-treated patients (all P <0.01). There were no serious adverse events. Conclusions Utilizing the sore throat pain model with multiple doses over 24 hours, flurbiprofen 8.75 mg lozenges were shown to be an effective, well-tolerated treatment for sore throat pain. Other pharmacologic actions (reduced difficulty swallowing and reduced throat swelling) and overall patient satisfaction from the flurbiprofen lozenges were also demonstrated in this multiple-dose implementation of the sore throat pain model. Trial registration This trial was registered with ClinicalTrials.gov, registration number: NCT01048866, registration date: January 13, 2010. PMID:24988909

  17. Effect of Pneumoperitoneum and Lateral Position on Oropharyngeal Seal Pressures of Proseal LMA in Laparoscopic Urological Procedures.

    PubMed

    Rustagi, Preeti; Patkar, Geeta A; Ourasang, Anil Kumar; Tendolkar, Bharati A

    2017-02-01

    A sustained and effective oropharyngeal sealing with supraglottic airway is required to maintain the ventilation during laparoscopic surgery. Previous studies have observed the Oropharyngeal Seal Pressure (OSP) for Proseal Laryngeal Mask Airway (PLMA) after pneumoperitoneum in supine and trendelenburg position, where PLMA was found to be an effective airway device. This study was conducted with ProSeal LMA, for laparoscopic Urologic procedures done in lateral position. To measure OSP in supine and lateral position and to observe the effect of pneumoperitoneum in lateral position on OSP. Secondary objectives were to assess adequacy of ventilation and incidence of adverse events. A total number of 25 patients of American Society of Anaesthesiologists (ASA) physical status II and I were enrolled. After induction of anaesthesia using a standardized protocol, PLMA was inserted. Ryle's tube was inserted through drain tube. The position of PLMA was confirmed with ease of insertion of Ryle's tube and fibreoptic grading of vocal cords. Patients were then put in lateral position. The OSP was measured in supine position. This value was baseline comparison for OSP in lateral position and that after pneumoperitoneum. We assessed the efficacy of PLMA for ventilation, after carboperitoneum in lateral position (peak airway pressure, End Tidal Carbon dioxide (EtCO 2 ), SPO 2 ). Incidence of adverse effects (displacement of device, gastric insufflation, regurgitation, coughing, sore throat, blood on device, trauma) was also noted. The OSP was above Peak Airway Pressure (PAP) in supine (22.1±5.4 and 15.4±4.49cm of H 2 O) and lateral position (22.6±5.3 and 16.1±4.6). After pneumoperitoneum, which was in lateral position, there was statistically significant (p-value <0.05) increase in both PAP (19.96±4.015) and OSP (24.32±4.98, p-value 0.03). There was no intraoperative displacement of PLMA. There was no event of suboptimal oxygenation. EtCO 2 was always within normal limits. Gastric insufflation was present in one patient. One patient had coughing and blood was detected on device. Three patients had throat discomfort post-operatively. In this study, Oropharyngeal seal pressures with PLMA were found to increase after pneumoperitoneum in lateral position. PLMA forms an effective seal around airway and is an efficient and safe alternative for airway management in urological laparoscopic surgeries done in lateral position.

  18. Hoarseness

    MedlinePlus

    ... as fever, cough, sore throat, difficulty swallowing, weight loss, or fatigue? You may have one or more of the following tests: Laryngoscopy Throat culture Throat examination with a small mirror X-rays ...

  19. Risk factors for otolaryngological foreign bodies in Eastern Poland.

    PubMed

    Rybojad, Beata; Niedzielski, Artur; Niedzielska, Grazyna; Rybojad, Pawel

    2012-11-01

    To identify the sociodemographic characteristics and risk factors associated with suspected foreign bodies in the ear, nose, throat, airway, and esophagus among Polish children. Case series with chart review. Setting Tertiary care medical center. A retrospective analysis of the medical records of patients hospitalized for a suspected foreign body (FB) between 1998 and 2008 was conducted. Data regarding place of residence, presence of siblings, parents' educational status, seasonality, psychomotor development, age, and sex were collected and statistically analyzed. Of the 1011 patients with suspected foreign body insertion, 849 (84%) had a positive diagnosis. Of the confirmed foreign bodies, 96 were found in the tracheobronchial tree, 142 were found in the esophagus, and 611 were located in the external auditory canals, nasopharyngeal passage, tonsils, auricles, or lips. Sociodemographically, 596 of the children came from urban areas, with a preponderance of males (55%). Objects were removed more frequently in summer and autumn (60%). Children with siblings (53%) predominated. The majority of patients (52%) had parents with an elementary education. Food was the most frequent foreign body in children under 3 years of age. Patients with delayed psychomotor development constituted 1.6% of the analyzed population. Being male, 1 to 3 years of age, belonging to an urban family with siblings, and having parents with an elementary education increased the risk of foreign body insertion. Training caregivers about proper nutrition and safety rules when playing with children can reduce the risk of accidents related to foreign body insertion.

  20. Guideline for the management of acute sore throat.

    PubMed

    Pelucchi, C; Grigoryan, L; Galeone, C; Esposito, S; Huovinen, P; Little, P; Verheij, T

    2012-04-01

    The European Society for Clinical Microbiology and Infectious Diseases established the Sore Throat Guideline Group to write an updated guideline to diagnose and treat patients with acute sore throat. In diagnosis, Centor clinical scoring system or rapid antigen test can be helpful in targeting antibiotic use. The Centor scoring system can help to identify those patients who have higher likelihood of group A streptococcal infection. In patients with high likelihood of streptococcal infections (e.g. 3-4 Centor criteria) physicians can consider the use of rapid antigen test (RAT). If RAT is performed, throat culture is not necessary after a negative RAT for the diagnosis of group A streptococci. To treat sore throat, either ibuprofen or paracetamol are recommended for relief of acute sore throat symptoms. Zinc gluconate is not recommended to be used in sore throat. There is inconsistent evidence of herbal treatments and acupuncture as treatments for sore throat. Antibiotics should not be used in patients with less severe presentation of sore throat, e.g. 0-2 Centor criteria to relieve symptoms. Modest benefits of antibiotics, which have been observed in patients with 3-4 Centor criteria, have to be weighed against side effects, the effect of antibiotics on microbiota, increased antibacterial resistance, medicalisation and costs. The prevention of suppurative complications is not a specific indication for antibiotic therapy in sore throat. If antibiotics are indicated, penicillin V, twice or three times daily for 10 days is recommended. At the present, there is no evidence enough that indicates shorter treatment length. © 2012 The Authors. Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases.

  1. Meaningful relief with flurbiprofen 8.75 mg spray in patients with sore throat due to upper respiratory tract infection.

    PubMed

    de Looze, Ferdinandus; Russo, Marc; Bloch, Mark; Montgomery, Barney; Shephard, Adrian; DeVito, Robert

    2018-03-01

    Evaluate the efficacy of flurbiprofen 8.75 mg spray for sore throat relief. Randomized, double-blind study in adults with sore throat due to upper respiratory tract infection who took flurbiprofen (n = 249) or placebo spray (n = 256). Pain relief was assessed using the Sore Throat Relief Rating Scale. Flurbiprofen spray provided significantly greater relief versus placebo from 20 min to 6 h (p < 0.0001; maximum difference: 75 min). Sore throat severity was reduced ≥-2.2 on the Sore Throat Scale from 75 min to 6 h, indicating meaningful relief. Significantly more patients taking flurbiprofen spray reported ≥30 min of 'at least moderate' relief versus placebo over 6 h (p < 0.0001). Most adverse events were mild. Flurbiprofen spray provides rapid, long-lasting and clinically meaningful relief from sore throat (ANZCTR: ACTRN12612000457842).

  2. Streptococcal Infections

    MedlinePlus

    ... Group A strep causes Strep throat - a sore, red throat. Your tonsils may be swollen and have ... illness that follows strep throat. It causes a red rash on the body. Impetigo - a skin infection ...

  3. -dimensional thin shell wormhole with deformed throat can be supported by normal matter

    NASA Astrophysics Data System (ADS)

    Mazharimousavi, S. Habib; Halilsoy, M.

    2015-06-01

    From the physics standpoint the exotic matter problem is a major difficulty in thin shell wormholes (TSWs) with spherical/cylindrical throat topologies. We aim to circumvent this handicap by considering angle dependent throats in dimensions. By considering the throat of the TSW to be deformed spherical, i.e., a function of and , we present general conditions which are to be satisfied by the shape of the throat in order to have the wormhole supported by matter with positive density in the static reference frame. We provide particular solutions/examples to the constraint conditions.

  4. Throat or larynx cancer

    MedlinePlus

    Vocal cord cancer; Throat cancer; Laryngeal cancer; Cancer of the glottis; Cancer of oropharynx or hypopharynx ... use tobacco are at risk of developing throat cancer. Drinking too much alcohol over a long time ...

  5. Incidence, causes, severity and treatment of throat discomfort: a four-region online questionnaire survey

    PubMed Central

    2012-01-01

    Background Acute sore throat is commonly associated with viral infections. Consumers typically rely on over-the-counter treatments and other remedies to treat symptoms; however, limited information is available regarding consumer perceptions of sore throat or treatment needs. The aim of this study was to investigate perceptions of throat discomfort and how these influence attitudes and consumer behaviour with regard to treatment. Methods Online consumer surveys were completed by participants invited by email between 2003 and 2004 in four markets: the UK, France, Poland, and Malaysia. The questionnaire consisted of 24 questions that covered key issues surrounding throat discomfort including incidence in the past 12 months, causes, severity, effects on functionality and quality of life, actions taken to relieve throat discomfort, the efficacy of these approaches and the reasons behind using specific products. Results In total, 6465 men and women aged ≥18 years were surveyed, identifying 3514 participants who had suffered throat discomfort/irritation in the past 12 months (response rate of 54%). These participants completed the full survey. The breakdown of throat discomfort sufferers was: UK, 912; France, 899; Poland, 871; Malaysia, 832. A high proportion of respondents experienced one or more instances of throat discomfort in the previous 12 months, with an overall incidence of 54%. Infections including the common cold/influenza and other bacteria/viruses were commonly perceived causes of throat discomfort (72% and 46%, respectively). Physical and environmental factors were also perceived to be causative, including airborne pollution (28%), smoking (23%), and air conditioning (31%). Symptoms perceived to be caused by an infection were associated with a higher degree of suffering (mean degree of suffering for bacteria/virus and common cold/influenza; 3.4 and 3.0, respectively). Medicinal products were used for all perceived causes, but more commonly for sore throats thought to be caused by infections. Cold drinks were used more often for symptoms thought to be due to physical and environmental causes. Conclusions Not all throat discomfort is the same, as demonstrated by the range of perceived causes and the emotional and physical symptoms experienced. Patient expectations regarding treatment of throat discomfort differs and treatments should be tailored by pharmacists to suit the cause. PMID:22883470

  6. A multicentre, randomised, double-blind, single-dose study assessing the efficacy of AMC/DCBA Warm lozenge or AMC/DCBA Cool lozenge in the relief of acute sore throat

    PubMed Central

    2011-01-01

    Background Clinically proven over-the-counter (OTC) treatment options are becoming increasingly important in the self-management of acute sore throat. The aim of this study was to determine the analgesic and sensorial benefits of two different amylmetacresol/2,4-dichlorobenzyl alcohol (AMC/DCBA) throat lozenge formulation variants, AMC/DCBA Warm lozenge and AMC/DCBA Cool lozenge, compared with an unflavoured, non-medicated placebo lozenge in the relief of acute sore throat due to upper respiratory tract infections. Methods In this multicentre, randomised, double-blind, single-dose study, 225 adult patients with acute sore throat were randomly assigned to receive either one AMC/DCBA Warm lozenge (n = 77), one AMC/DCBA Cool lozenge (n = 74) or one unflavoured, non-medicated lozenge (matched for size, shape and demulcency; n = 74). After baseline assessments, patients received their assigned lozenge and completed four rating assessments at 11 timepoints from 1 to 120 minutes post dose. Analgesic properties were assessed by comparing severity of throat soreness and sore throat relief ratings. Difficulty in swallowing, throat numbness, functional, sensorial and emotional benefits were also assessed. Results Both the AMC/DCBA Warm and AMC/DCBA Cool lozenge induced significant analgesic, functional, sensorial and emotional effects compared with the unflavoured, non-medicated lozenge. Sore throat relief, improvements in throat soreness and difficulty in swallowing, and throat numbness were observed as early as 1-5 minutes, and lasted up to 2 hours post dose. Sensorial benefits of warming and cooling associated with the AMC/DCBA Warm and AMC/DCBA Cool lozenge, respectively, were experienced soon after first dose, and in the case of the latter, it lasted long after the lozenge had dissolved. Emotional benefits of feeling better, happier, less distracted and less frustrated were reported in those taking either of the AMC/DCBA throat lozenge variants, with no differences in adverse events compared with the unflavoured, non-medicated lozenge. Conclusions AMC/DCBA Warm and AMC/DCBA Cool lozenges are well-tolerated and effective OTC treatment options, offering functional, sensorial and emotional benefits to patients with acute sore throat, over and above that of the rapid efficacy effects provided. Trial registration ISRCTN: ISRCTN00003567 PMID:21332976

  7. Sore Throat (For Parents)

    MedlinePlus

    ... another illness, like a cold , the flu , or mononucleosis . They also can be caused by a strep ... topic for: Parents Kids Teens Strep Throat Coughing Mononucleosis Strep Test: Rapid Strep Test: Throat Culture Flu ...

  8. 21 CFR 201.315 - Over-the-counter drugs for minor sore throats; suggested warning.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Over-the-counter drugs for minor sore throats... Drug Products § 201.315 Over-the-counter drugs for minor sore throats; suggested warning. The Food and... counter for the relief of minor irritations of the mouth or throat. It will not object to the labeling of...

  9. 21 CFR 201.315 - Over-the-counter drugs for minor sore throats; suggested warning.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Over-the-counter drugs for minor sore throats... Drug Products § 201.315 Over-the-counter drugs for minor sore throats; suggested warning. The Food and... counter for the relief of minor irritations of the mouth or throat. It will not object to the labeling of...

  10. Prevention of Influenza and other Respiratory Diseases

    DTIC Science & Technology

    1977-08-01

    Virus isolation was attempted from throat washings collected in beef extract broth. These were stored at approximately -50 In a refrigerator at Lowry... throat cultures and blood specimens with individual Informed consent. Cooperation was remarkably good. Throat cultures were taken from...more rapidly in Rhesus monkey kidney tissue culture than did the A/Denver/77 strains. Viruses were isolated from 9 of 13 throat washings from

  11. School Nurses on the Front Lines of Medicine: A Student With Fever and Sore Throat.

    PubMed

    Olympia, Robert P

    2016-05-01

    Fever and sore throat are common chief complaints encountered by school nurses. This article explains the etiology of both fever and sore throat in children, describes the office assessment, and delineates life-threatening complications associated with fever and sore throat that may prompt the school nurse to transfer the child to a local emergency department. © 2016 The Author(s).

  12. Indirect and direct methods for measuring a dynamic throat diameter in a solid rocket motor

    NASA Astrophysics Data System (ADS)

    Colbaugh, Lauren

    In a solid rocket motor, nozzle throat erosion is dictated by propellant composition, throat material properties, and operating conditions. Throat erosion has a significant effect on motor performance, so it must be accurately characterized to produce a good motor design. In order to correlate throat erosion rate to other parameters, it is first necessary to know what the throat diameter is throughout a motor burn. Thus, an indirect method and a direct method for determining throat diameter in a solid rocket motor are investigated in this thesis. The indirect method looks at the use of pressure and thrust data to solve for throat diameter as a function of time. The indirect method's proof of concept was shown by the good agreement between the ballistics model and the test data from a static motor firing. The ballistics model was within 10% of all measured and calculated performance parameters (e.g. average pressure, specific impulse, maximum thrust, etc.) for tests with throat erosion and within 6% of all measured and calculated performance parameters for tests without throat erosion. The direct method involves the use of x-rays to directly observe a simulated nozzle throat erode in a dynamic environment; this is achieved with a dynamic calibration standard. An image processing algorithm is developed for extracting the diameter dimensions from the x-ray intensity digital images. Static and dynamic tests were conducted. The measured diameter was compared to the known diameter in the calibration standard. All dynamic test results were within +6% / -7% of the actual diameter. Part of the edge detection method consists of dividing the entire x-ray image by an average pixel value, calculated from a set of pixels in the x-ray image. It was found that the accuracy of the edge detection method depends upon the selection of the average pixel value area and subsequently the average pixel value. An average pixel value sensitivity analysis is presented. Both the indirect method and the direct method prove to be viable approaches to determining throat diameter during solid rocket motor operation.

  13. Randomised, double-blind, placebo-controlled studies on flurbiprofen 8.75 mg lozenges in patients with/without group A or C streptococcal throat infection, with an assessment of clinicians' prediction of 'strep throat'.

    PubMed

    Shephard, A; Smith, G; Aspley, S; Schachtel, B P

    2015-01-01

    Diagnosing group A streptococcus (Strep A) throat infection by clinical examination is difficult, and misdiagnosis may lead to inappropriate antibiotic use. Most patients with sore throat seek symptom relief rather than antibiotics, therefore, therapies that relieve symptoms should be recommended to patients. We report two clinical trials on the efficacy and safety of flurbiprofen 8.75 mg lozenge in patients with and without streptococcal sore throat. The studies enrolled adults with moderate-to-severe throat symptoms (sore throat pain, difficulty swallowing and swollen throat) and a diagnosis of pharyngitis. The practitioner assessed the likelihood of Strep A infection based on historical and clinical findings. Patients were randomised to flurbiprofen 8.75 mg or placebo lozenges under double-blind conditions and reported the three throat symptoms at baseline and at regular intervals over 24 h. A total of 402 patients received study medication (n = 203 flurbiprofen, n = 199 placebo). Throat culture identified Strep A in 10.0% of patients and group C streptococcus (Strep C) in a further 14.0%. The practitioners' assessments correctly diagnosed Strep A in 11/40 cases (sensitivity 27.5%, and specificity 79.7%). A single flurbiprofen lozenge provided significantly greater relief than placebo for all three throat symptoms, lasting 3-4 h for patients with and without Strep A/C. Multiple doses of flurbiprofen lozenges over 24 h also led to symptom relief, although not statistically significant in the Strep A/C group. There were no serious adverse events. The results highlight the challenge of identifying Strep A based on clinical features. With the growing problem of antibiotic resistance, non-antibiotic treatments should be considered. As demonstrated here, flurbiprofen 8.75 mg lozenges are an effective therapeutic option, providing immediate and long-lasting symptom relief in patients with and without Strep A/C infection. © 2014 John Wiley & Sons Ltd.

  14. Mononucleosis - view of the throat (image)

    MedlinePlus

    Infectious mononucleosis causes a sore throat, enlarged lymph nodes, and fatigue. The throat may appear red and the tonsils covered with a whitish material. Mononucleosis and severe streptococcal tonsillitis appear quite similar. Unless ...

  15. What is LPR (Laryngopharyngeal Reflux)

    MedlinePlus

    ... What role does an ear, nose, and throat specialist have in treating LPR? Laryngopharyngeal reflux (LPR) is ... by an otolaryngologist or ear, nose, and throat specialist. Symptoms related to LPR including throat discomfort, laryngitis, ...

  16. Tonsillitis (For Parents)

    MedlinePlus

    ... streptococci bacteria are causing the infection. If it's strep throat , your child will need treatment with an antibiotic ... Tonsils and Tonsillectomies Peritonsillar Abscess Strep Test: Rapid Strep Throat Strep Test: Throat Culture Enlarged Adenoids Having Your ...

  17. Antibiotics for preventing recurrent sore throat.

    PubMed

    Ng, Gareth J Y; Tan, Stephanie; Vu, Anh N; Del Mar, Chris B; van Driel, Mieke L

    2015-07-14

    Antibiotics are sometimes used to prevent recurrent sore throat, despite concern about resistance. However, there is conflicting primary evidence regarding their effectiveness. To assess the effects of antibiotics in patients with recurrent sore throat. The Cochrane Ear, Nose and Throat Disorders Group (CENTDG) Trials Search Co-ordinator searched the CENTDG Trials Register; Central Register of Controlled Trials (CENTRAL 2015, Issue 5); PubMed; EMBASE; CINAHL; Web of Science; Clinicaltrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 25 June 2015. Randomised controlled trials (RCTs) of antibiotics in adults and children suffering from pre-existing recurrent sore throat, defined as three or more sore throats in a year, examining the incidence of sore throat recurrence, with follow-up of at least 12 months post-antibiotic therapy. Two authors independently assessed trial quality and extracted data. Multiple attempts to contact the authors of one study yielded no response. We identified no trials that met the inclusion criteria for the review. We discarded the majority of the references retrieved from our search following screening of the title and abstract. We formally excluded four studies following review of the full-text report. There is insufficient evidence to determine the effectiveness of antibiotics for preventing recurrent sore throat. This finding must be balanced against the known adverse effects and cost of antibiotic therapy, when considering antibiotics for this purpose. There is a need for high quality RCTs that compare the effects of antibiotics versus placebo in adults and children with pre-existing recurrent sore throat on the following outcomes: incidence of sore throat recurrence, adverse effects, days off work and absence from school, and the incidence of complications. Future studies should be conducted and reported according to the CONSORT statement.

  18. Efficacy of flurbiprofen 8.75 mg spray in patients with sore throat due to an upper respiratory tract infection: A randomised controlled trial.

    PubMed

    de Looze, Ferdinandus; Russo, Marc; Bloch, Mark; Montgomery, Barney; Shephard, Adrian; Smith, Gary; Aspley, Sue

    2016-06-01

    Viral infections cause most cases of pharyngitis (sore throat); consequently, antibiotics are generally not warranted. However, a treatment targeting pain and inflammation, e.g. a topical non-steroidal anti-inflammatory spray, may be helpful for patients. To evaluate the efficacy and safety of flurbiprofen 8.75 mg spray. This randomised, double-blind, parallel group study was conducted at six community-based clinical research centres in Australia and two in New Zealand. Adults with sore throat due to upper respiratory tract infection (onset ≤ four days) took one dose of flurbiprofen (n = 249) or placebo spray (n = 256); after six hours, they could re-dose every three-six hours as required, for three days (max. five doses/day). The primary endpoint was the area under the change from baseline curve in throat soreness from zero-two hours (AUC0-2h). The change from baseline in other sore throat symptoms also assessed efficacy. The mean AUC0-2h for throat soreness was significantly greater with flurbiprofen spray (-1.82; 95% CI: -1.98 to 1.65) compared with placebo (-1.13; 95% CI: -1.27 to 0.99) (P < 0.0001). Significantly greater reductions from baseline were observed with flurbiprofen spray compared with placebo from the first time-points assessed (five minutes for throat soreness/difficulty swallowing, 20 minutes for sore throat pain intensity and 30 minutes for swollen throat) for up to six hours (P < 0.05 for all). There was no significant difference in adverse events between treatment groups during the three-day study. Flurbiprofen spray provides rapid and long-lasting relief from sore throat symptoms, and is well-tolerated over three days.

  19. Throat hit in users of the electronic cigarette: An exploratory study.

    PubMed

    Etter, Jean-François

    2016-02-01

    A cross-sectional survey on the Internet in 2012-2014 was used to study the "throat hit," the specific sensation in the throat felt by users of e-cigarettes. Participants were 1672 current users of e-cigarettes, visitors of Websites dedicated to e-cigarettes and to smoking cessation. It was assessed whether the strength of the throat hit was associated with the characteristics of e-cigarettes and e-liquids, modifications of the devices, patterns of use, reasons for use, satisfaction with e-cigarettes, dependence on e-cigarettes, smoking behavior, and perceived effects on smoking. The strongest throat hit was obtained by using better-quality models and liquids with high nicotine content. Those who reported a "very strong" throat hit used liquids with 17.3 mg/mL nicotine, versus 7.1 mg/mL for those reporting a "very weak" hit (p < .001). The strength of the throat hit was also associated with ratings of dependence on e-cigarettes, and with the perceived efficacy of e-cigarettes to relieve craving for tobacco and to facilitate smoking cessation. All the variables assessing satisfaction with e-cigarettes were associated with a stronger throat hit. From a public health perspective, there is a trade-off between e-cigarette models that provide high levels of nicotine, a strong throat hit, high satisfaction, and more effects on smoking, but may also be addictive, and models than contain less nicotine and are less addictive, but produce a weaker throat hit, are less satisfactory, and are possibly less efficient at helping people quit smoking. This trade-off must be kept in mind when regulating e-cigarettes. (c) 2016 APA, all rights reserved).

  20. Streptococcal throat infections and exacerbation of chronic plaque psoriasis: a prospective study.

    PubMed

    Gudjonsson, J E; Thorarinsson, A M; Sigurgeirsson, B; Kristinsson, K G; Valdimarsson, H

    2003-09-01

    Guttate psoriasis has a well-known association with streptococcal throat infections but the effects of these infections in patients with chronic psoriasis remains to be evaluated in a prospective study. To determine whether streptococcal throat infections are more common in and can cause exacerbation in patients with chronic psoriasis. Two hundred and eight patients with chronic plaque psoriasis and 116 unrelated age-matched household controls were followed for 1 year. At recruitment all patients were examined, their disease severity scored and throat swabs taken. Patients and corresponding controls were then re-examined and tested for streptococcal colonization whenever they reported sore throat or exacerbation of their psoriasis during the study period. The psoriasis patients reported sore throat significantly more often than controls (61 of 208 vs. three of 116, P < 0.0001), and beta-haemolytic streptococci of Lancefield groups A, C and G (M protein-positive streptococci) were more often cultured from the patients than the controls (19 of 208 vs. one of 116, P = 0.003). A significant exacerbation of psoriasis (P = 0.004) was observed only if streptococci were isolated and the patients were assessed 4 days or later after the onset of sore throat. No difference was observed between groups A, C or G streptococci in this respect. This study confirms anecdotal and retrospective reports that streptococcal throat infections can cause exacerbation of chronic plaque psoriasis. It is concluded that psoriasis patients should be encouraged to report sore throat to their physician and that early treatment of streptococcal throat infections might be beneficial in psoriasis. A controlled trial for assessing potential benefits of tonsillectomy in patients with severe psoriasis should also be considered.

  1. Recurring Strep Throat: When Is Tonsillectomy Useful?

    MedlinePlus

    ... throat: When is tonsillectomy useful? My 7-year-old daughter has been diagnosed with strep throat four ... of Privacy Practices Notice of Nondiscrimination Manage Cookies Advertising Mayo Clinic is a not-for-profit organization ...

  2. Tonsils and Tonsillectomies (For Parents)

    MedlinePlus

    ... may order a throat culture to check for strep throat. About Tonsillectomies Doctors might recommend surgical removal of ... Kids With No Tonsils More Susceptible to Infections? Strep Throat Preparing Your Child for Surgery Tonsillitis Enlarged Adenoids ...

  3. Strep Throat (For Teens)

    MedlinePlus

    ... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body ... teens. In fact, strep bacteria cause almost a third of all sore throats. Strep throat usually requires ...

  4. The role of colour in signalling and male choice in the agamid lizard Ctenophorus ornatus.

    PubMed Central

    LeBas, N R; Marshall, N J

    2000-01-01

    Bright coloration and complex visual displays are frequent and well described in many lizard families. Reflectance spectrometry which extends into the ultraviolet (UV) allows measurement of such coloration independent of our visual system. We examined the role of colour in signalling and mate choice in the agamid lizard Ctenophorus ornatus. We found that throat reflectance strongly contrasted against the granite background of the lizards' habitat. The throat may act as a signal via the head-bobbing and push-up displays of C. ornatus. Dorsal coloration provided camouflage against the granite background, particularly in females. C. ornatus was sexually dichromatic for all traits examined including throat UV reflectance which is beyond human visual perception. Female throats were highly variable in spectral reflectance and males preferred females with higher throat chroma between 370 and 400 nm. However, female throat UV chroma is strongly correlated to both throat brightness and chest UV chroma and males may choose females on a combination of these colour variables. There was no evidence that female throat or chest coloration was an indicator of female quality. However, female brightness significantly predicted a female's laying date and, thus, may signal receptivity. One function of visual display in this species appears to be intersexual signalling, resulting in male choice of females. PMID:10737400

  5. When a Sore Throat Is a More Serious Infection

    MedlinePlus

    ... often called Hand, Foot, and Mouth disease). Infectious mononucleosis can produce a sore throat, often with marked ... most young children who are infected with the mononucleosis virus have few or no symptoms. Strep throat ...

  6. Streptococcal screen

    MedlinePlus

    Rapid strep test ... recommend this test if you have signs of strep throat, which include: Fever Sore throat Tender and ... A negative strep screen most often means group A streptococcus is not present. It is unlikely that you have strep throat. ...

  7. Difference between a Sore Throat, Strep, and Tonsillitis

    MedlinePlus

    ... extreme trouble swallowing (causing her to drool). Throat culture This may indicate a more serious infection. The ... examine your child and may perform a throat culture to determine the nature of the infection. To ...

  8. Strep Test: Throat Culture (For Parents)

    MedlinePlus

    ... Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Strep Test: Throat Culture KidsHealth / For Parents / Strep Test: Throat Culture What's ...

  9. A five-year experience with throat cultures.

    PubMed

    Shank, J C; Powell, T A

    1984-06-01

    This study addresses the usefulness of the throat culture in a family practice residency setting and explores the following questions: (1) Do faculty physicians clinically identify streptococcal pharyngitis better than residents? (2) With time, will residents and faculty physicians improve in their diagnostic accuracy? (3) Should the throat culture be used always, selectively, or never? A total of 3,982 throat cultures were obtained over a five-year study period with 16 percent positive for beta-hemolytic streptococci. The results were compared with the physician's clinical diagnosis of either "nonstreptococcal" (category A) or "streptococcal" (category B). Within category A, 363 of 3,023 patients had positive cultures (12 percent clinical diagnostic error rate). Within category B, 665 of 959 patients had negative cultures (69 percent clinical diagnostic error rate). Faculty were significantly better than residents in diagnosing streptococcal pharyngitis, but not in diagnosing nonstreptococcal sore throats. Neither faculty nor residents improved their diagnostic accuracy over time. Regarding age-specific recommendations, the findings support utilizing a throat culture in all children aged 2 to 15 years with sore throat, but in adults only when the physician suspects streptococcal pharyngitis.

  10. Polygyny, mate-guarding, and posthumous fertilization as alternative male mating strategies.

    PubMed

    Zamudio, K R; Sinervo, B

    2000-12-19

    Alternative male mating strategies within populations are thought to be evolutionarily stable because different behaviors allow each male type to successfully gain access to females. Although alternative male strategies are widespread among animals, quantitative evidence for the success of discrete male strategies is available for only a few systems. We use nuclear microsatellites to estimate the paternity rates of three male lizard strategies previously modeled as a rock-paper-scissors game. Each strategy has strengths that allow it to outcompete one morph, and weaknesses that leave it vulnerable to the strategy of another. Blue-throated males mate-guard their females and avoid cuckoldry by yellow-throated "sneaker" males, but mate-guarding is ineffective against aggressive orange-throated neighbors. The ultradominant orange-throated males are highly polygynous and maintain large territories; they overpower blue-throated neighbors and cosire offspring with their females, but are often cuckolded by yellow-throated males. Finally, yellow-throated sneaker males sire offspring via secretive copulations and often share paternity of offspring within a female's clutch. Sneaker males sire more offspring posthumously, indicating that sperm competition may be an important component of their strategy.

  11. Safety and efficacy of a traditional herbal medicine (Throat Coat) in symptomatic temporary relief of pain in patients with acute pharyngitis: a multicenter, prospective, randomized, double-blinded, placebo-controlled study.

    PubMed

    Brinckmann, Josef; Sigwart, Herbert; van Houten Taylor, Leslie

    2003-04-01

    To investigate the safety and efficacy of Throat Coat) (Traditional Medicinals,) Sebastopol, CA), a traditional demulcent herbal tea, in comparison with a placebo tea in the symptomatic treatment of acute pharyngitis. Multicenter, prospective, randomized, double-blinded, placebo-controlled, two-armed, parallel-group clinical trial. Three primary care clinics in Duluth, MN, Madison, WI, and Middleton, WI. Patients of both genders (>or=18 years of age) with clinical diagnoses of acute pharyngitis. Patients (n = 60) were randomly assigned to receive 5-8 oz of Throat Coat (n = 30) or a placebo (n = 30), four to six times daily. The study period was 2 to 7 days with a window for the follow-up visit of 2-10 days accounting for the variable duration of sore throat symptoms. Primary efficacy parameter: sum of pain intensity differences (SPID) for pain in throat on swallowing, calculated as the area under the curve (AUC) of pain intensity difference scores (assessed at 1 minute, 5 minutes, 10 minutes, 15 minutes, 20 minutes, and 30 minutes after treatment). Secondary efficacy parameter: total pain relief (TOTPAR), calculated as the AUC from time 0 (baseline) to 30 minutes of pain relief (assessed at 1 minute, 5 minutes, 10 minutes, 15 minutes, 20 minutes, and 30 minutes). Compared to placebo, intensity of throat pain when swallowing was significantly reduced by Throat Coat in intention to treat and valid for efficacy analysis (VEA). Significant differences in change from baseline pain were observed at 5 min (p = 0.007), 10 min (p = 0.005), 15 minutes (p = 0.01), 20 minutes (p = 0.05), and 30 minutes (p = 0.04) after completion of the first dose (VEA analysis). There was a statistically significant improvement of SPID in the Throat Coat-treated group: Least square means +/- standard error of the means (SEM) of SPID were -16.5 +/- 13.9 in the placebo group and -43.8 +/- 11.9 in the Throat Coat-treated group (p = 0.012). TOTPAR was also significantly higher in the Throat Coat-treated group: Least square means +/- SEM of TOTPAR were 32.4 +/- 12.8 in the placebo group and 53.6 +/- 10.9 in the Throat Coat-treated group (p = 0.031). This study shows that Throat Coat is significantly superior to placebo and provided a rapid, temporary relief of sore throat pain in patients with pharyngitis.

  12. Dual-fuel, dual-throat engine preliminary analysis

    NASA Technical Reports Server (NTRS)

    Obrien, C. J.

    1979-01-01

    A propulsion system analysis of the dual fuel, dual throat engine for launch vehicle applications was conducted. Basic dual throat engine characterization data were obtained to allow vehicle optimization studies to be conducted. A preliminary baseline engine system was defined.

  13. Strep throat

    MedlinePlus

    ... repeated cases of strep still occur in a family, you might check to see if someone is a strep carrier. Carriers have strep in their throats, but the bacteria do not make them sick. Sometimes, treating them can prevent others from getting strep throat.

  14. Scoop on Strep Throat (For Kids)

    MedlinePlus

    ... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body Works ... Educators Search English Español Strep Throat KidsHealth / For Kids / Strep Throat What's in this article? What Is ...

  15. Use of antibiotics in the management of sore throat.

    PubMed

    Wilkinson, Ann Elizabeth

    2015-03-01

    As the number of antibiotic-resistant strains of bacteria rises, it becomes crucial that decisions about the use of antibiotics are based on sound evidence. This article offers a case study to explore the treatment of patients with sore throat who present to minor injury settings. It describes some 'red flag' presentations, discusses the pros and cons of prescribing antibiotics for sore throat, and describes some scoring systems that can help differentiate between bacterial and viral throat infections.

  16. Comparison of Effectiveness of Betamethasone gel Applied to the Tracheal Tube and IV Dexamethasone on Postoperative Sore Throat: A Randomized Controlled Trial.

    PubMed

    Tabari, Masumeh; Soltani, Ghasem; Zirak, Nahid; Alipour, Moammad; Khazaeni, Kamran

    2013-09-01

    Postoperative sore throat is a common complaint in patients with endotracheal intubation and has potentially dangerous complications. This randomized controlled trial study investigated the incidence of postoperative sore throat after general anesthesia when betamethasone gel is applied to a tracheal tube compared with when IV dexamethasone is prescribed. Two hundred and twenty five American Society of Anesthesiologist (ASA)-class I and II patients undergoing elective abdominal surgery with tracheal intubation were randomly divided into three groups: betamethasone gel, intravenous (IV) dexamethasone, and control groups. In the post-anesthesia care unit, a blinded anesthesiologist interviewed all patients regarding postoperative sore throat at 1,6, and 24 hours after surgery. The incidence of sore throat was significantly lower in the betamethasone gel group compared with the IV dexamethasone and control groups, 1, 6, and 24 hours after surgery. In the first day after surgery 10.7% of the betamethasone group had sore throat whereas 26.7% of the IV dexamethasone group and 30.7% of the control group had sore throat. Bucking before extubation was observed in 14(18.4%), 8(10.4%), and 9(12.2%) patients, in the IV dexamethasone, betamethasone gel, and control group, respectively. We concluded that wide spread application of betamethasone gel over tracheal tubes effectively mitigates postoperative sore throat, compared with IV dexamethasone application.

  17. Improvements in throat function and qualities of sore throat from locally applied flurbiprofen 8.75 mg in spray or lozenge format: findings from a randomized trial of patients with upper respiratory tract infection in the Russian Federation.

    PubMed

    Burova, Natalia; Bychkova, Valeria; Shephard, Adrian

    2018-01-01

    To assess the speed of relief provided by flurbiprofen 8.75 mg spray and lozenge and their effect on many of the different qualities and characteristics of throat pain and discomfort, and the many articulations of the broad term "sore throat" (ST). Four hundred and forty adults with recent-onset, moderate-to-severe ST due to upper respiratory tract infection (URTI) were randomized to a single dose of either flurbiprofen 8.75 mg spray (n=218) or flurbiprofen 8.75 mg lozenge (n=222). Throat swabs for bacterial culture were taken at baseline. ST relief was assessed at 1 minute, 1 and 2 hours post-dose using the Sore Throat Relief Rating Scale. The change from baseline at 1 and 2 hours post-dose in difficulty swallowing and swollen throat was assessed using the difficulty swallowing scale and the swollen throat scale, respectively. Patients' experience of URTI symptoms was assessed using a URTI questionnaire at baseline and 2 hours post-dose. The change in Qualities of Sore Throat Index, a 10-item index of qualities of ST, from baseline at 2 hours post-dose was also measured. ST relief was evident in the spray and the lozenge treatment groups at 1 minute, 1 and 2 hours post-dose ( P >0.05). In both groups, scores for difficulty swallowing and swollen throat significantly improved at 1 and 2 hours post-dose compared with baseline. At 2 hours post-dose, the number of patients experiencing URTI symptoms that can be attributed to or associated with ST decreased relative to baseline. The mean change from baseline to 2 hours post-dose for each individual score on the Qualities of Sore Throat Index showed significant improvements for flurbiprofen spray and lozenge (all P <0.0001). Non-inferiority was established, and flurbiprofen spray and lozenge provided effective relief from ST pain and many of the other commonly reported qualities of ST.

  18. Comparison of Intralaminar and Interlaminar Mode-I Fracture Toughness of Unidirectional IM7/8552 Graphite/Epoxy Composite

    NASA Technical Reports Server (NTRS)

    Czabaj, Michael W.; Ratcliffe, James

    2012-01-01

    The intralaminar and interlaminar mode-I fracture-toughness of a unidirectional IM7/8552 graphite/epoxy composite were measured using compact tension (CT) and double cantilever beam (DCB) test specimens, respectively. Two starter crack geometries were considered for both the CT and DCB specimen configurations. In the first case, starter cracks were produced by 12.5 micron thick, Teflon film inserts. In the second case, considerably sharper starter cracks were produced by fatigue precracking. For each specimen configuration, use of the Teflon film starter cracks resulted in initially unstable crack growth and artificially high initiation fracture-toughness values. Conversely, specimens with fatigue precracks exhibited stable growth onset and lower initiation fracture toughness. For CT and DCB specimens with fatigue precracks, the intralaminar and interlaminar initiation fracture toughnesses were approximately equal. However, during propagation, the CT specimens exhibited more extensive fiber bridging, and rapidly increasing R-curve behavior as compared to the DCB specimens. Observations of initiation and propagation of intralaminar and interlaminar fracture, and the measurements of fracture toughness, were supported by fractographic analysis using scanning electron microscopy.

  19. Orbital transfer vehicle 3000 LBF thrust chamber assembly hot fire test program

    NASA Technical Reports Server (NTRS)

    Schneider, Judy; Hayden, Warren R.

    1988-01-01

    The Aerojet Orbital Transfer Vehicle (OTV) Thrust Chamber Assembly (TCA) concept consists of a hydrogen cooled chamber, and annular injector, and an oxygen cooled centerbody. The hot fire testing of a heat sink version of the chamber with only the throat section using hydrogen cooling is documented. Hydraulic performance of the injector and cooled throat were verified by water flow testing prior to TCA assembly. The cooled throat was proof tested to 3000 psia to verify the integrity of the codeposited EF nickel-cobalt closeout. The first set of hot fire tests were conducted with a heat sink throat to obtain heat flux information. After demonstration of acceptable heat fluxes, the heat sink throat was replaced with the LH2 cooled throat section. Fourteen tests were conducted with a heat sink chamber and throat at chamber pressures of 85 to 359 psia. The injector face was modified at this time to add more face coolant flow. Ten tests were then conducted at chamber pressures of 197 to 620 psia. Actual heat fluxes at the higher chamber pressure range were 23 percent higher than the average of 10 Btu/in 2 predicted.

  20. Internal Performance of a Fixed-Shroud Nonaxisymmetric Nozzle Equipped with an Aft-Hood Exhaust Deflector

    NASA Technical Reports Server (NTRS)

    Asbury, Scott C.

    1997-01-01

    An investigation was conducted in the model preparation area of the Langley 16-Foot Transonic Tunnel to determine the internal performance of a fixed-shroud nonaxisymmetric nozzle equipped with an aft-hood exhaust deflector. Model geometric parameters investigated included nozzle power setting, aft-hood deflector angle, throat area control with the aft-hood deflector deployed, and yaw vector angle. Results indicate that cruise configurations produced peak performance in the range consistent with previous investigations of nonaxisymmetric convergent-divergent nozzles. The aft-hood deflector produced resultant pitch vector angles that were always less than the geometric aft-hood deflector angle when the nozzle throat was positioned upstream of the deflector exit. Significant losses in resultant thrust ratio occurred when the aft-hood deflector was deployed with an upstream throat location. At each aft-hood deflector angle, repositioning the throat to the deflector exit improved pitch vectoring performance and, in some cases, substantially improved resultant thrust ratio performance. Transferring the throat to the deflector exit allowed the flow to be turned upstream of the throat at subsonic Mach numbers, thereby eliminating losses associated with turning supersonic flow. Internal throat panel deflections were largely unsuccessful in generating yaw vectoring.

  1. Polygyny, mate-guarding, and posthumous fertilization as alternative male mating strategies

    PubMed Central

    Zamudio, Kelly R.; Sinervo, Barry

    2000-01-01

    Alternative male mating strategies within populations are thought to be evolutionarily stable because different behaviors allow each male type to successfully gain access to females. Although alternative male strategies are widespread among animals, quantitative evidence for the success of discrete male strategies is available for only a few systems. We use nuclear microsatellites to estimate the paternity rates of three male lizard strategies previously modeled as a rock-paper-scissors game. Each strategy has strengths that allow it to outcompete one morph, and weaknesses that leave it vulnerable to the strategy of another. Blue-throated males mate-guard their females and avoid cuckoldry by yellow-throated “sneaker” males, but mate-guarding is ineffective against aggressive orange-throated neighbors. The ultradominant orange-throated males are highly polygynous and maintain large territories; they overpower blue-throated neighbors and cosire offspring with their females, but are often cuckolded by yellow-throated males. Finally, yellow-throated sneaker males sire offspring via secretive copulations and often share paternity of offspring within a female's clutch. Sneaker males sire more offspring posthumously, indicating that sperm competition may be an important component of their strategy. PMID:11106369

  2. Active shape control of composite blades using shape memory actuation

    NASA Astrophysics Data System (ADS)

    Chandra, Ramesh

    2001-10-01

    This paper presents active shape control of composite beams using shape memory actuation. Shape memory alloy (SMA) bender elements trained to memorize bending shape were used to induce bending and twisting deformations in composite beams. Bending-torsion coupled graphite-epoxy and kevlar-epoxy composite beams with Teflon inserts were manufactured using an autoclave-molding technique. Teflon inserts were replaced by trained SMA bender elements. Composite beams with SMA bender elements were activated by heating these using electrical resistive heating and the bending and twisting deformations of the beams were measured using a mirror and laser system. The structural response of the composite beams activated by SMA elements was predicted using the Vlasov theory, where these beams were modeled as open sections with many branches. The bending moment induced by a SMA bender element was calculated from its experimentally determined memorized shape. The bending, torsion, and bending-torsion coupling stiffness coefficients of these beams were obtained using analytical formulation of an open-section composite beam with many branches (Vlasov theory).

  3. Redox-controlled potassium intercalation into two polyaromatic hydrocarbon solids

    NASA Astrophysics Data System (ADS)

    Romero, F. Denis; Pitcher, M. J.; Hiley, C. I.; Whitehead, G. F. S.; Kar, S.; Ganin, A. Y.; Antypov, D.; Collins, C.; Dyer, M. S.; Klupp, G.; Colman, R. H.; Prassides, K.; Rosseinsky, M. J.

    2017-07-01

    Alkali metal intercalation into polyaromatic hydrocarbons (PAHs) has been studied intensely after reports of superconductivity in a number of potassium- and rubidium-intercalated materials. There are, however, no reported crystal structures to inform our understanding of the chemistry and physics because of the complex reactivity of PAHs with strong reducing agents at high temperature. Here we present the synthesis of crystalline K2Pentacene and K2Picene by a solid-solid insertion protocol that uses potassium hydride as a redox-controlled reducing agent to access the PAH dianions, and so enables the determination of their crystal structures. In both cases, the inserted cations expand the parent herringbone packings by reorienting the molecular anions to create multiple potassium sites within initially dense molecular layers, and thus interact with the PAH anion π systems. The synthetic and crystal chemistry of alkali metal intercalation into PAHs differs from that into fullerenes and graphite, in which the cation sites are pre-defined by the host structure.

  4. The effect of cutting conditions on power inputs when machining

    NASA Astrophysics Data System (ADS)

    Petrushin, S. I.; Gruby, S. V.; Nosirsoda, Sh C.

    2016-08-01

    Any technological process involving modification of material properties or product form necessitates consumption of a certain power amount. When developing new technologies one should take into account the benefits of their implementation vs. arising power inputs. It is revealed that procedures of edge cutting machining are the most energy-efficient amongst the present day forming procedures such as physical and technical methods including electrochemical, electroerosion, ultrasound, and laser processing, rapid prototyping technologies etc, such as physical and technical methods including electrochemical, electroerosion, ultrasound, and laser processing, rapid prototyping technologies etc. An expanded formula for calculation of power inputs is deduced, which takes into consideration the mode of cutting together with the tip radius, the form of the replaceable multifaceted insert and its wear. Having taken as an example cutting of graphite iron by the assembled cutting tools with replaceable multifaceted inserts the authors point at better power efficiency of high feeding cutting in comparison with high-speed cutting.

  5. Diagnosis of Group A Streptococcal Infections Directly From Throat Gargle.

    DTIC Science & Technology

    1981-06-01

    Streptococcal Infection Strep Throat Latex agglutination 20. ARVAT(Continue an revere side it neessar and identify by block num~ber) The diagnosis of... THROAT GARGLE ,-I E. A. EDWARDS, 1. A. PH1WPS & W. C. SUITER REPORT NO. 81-20 DTIC IELECTE VAL A11OCT I lSlt P.O. BOX 8022 SAN DIEGO, CALIFORNIA 92138...AVAL MICAL RESEARCH AND DEVELOPMENT COMMAND BE0hESDA, MARYLAND £ 81 9 30 069 (. DIAGNOSIS OF QROUP A STREPTOCOCCAL INFECTIONS ~1IRECTLY FROM ThROAT

  6. Characterization and Persistence of Staphylococcus aureus Strains Isolated from the Anterior Nares and Throats of Healthy Carriers in a Mexican Community▿

    PubMed Central

    Hamdan-Partida, Aída; Sainz-Espuñes, Teresita; Bustos-Martínez, Jaime

    2010-01-01

    Healthy carriers of Staphylococcus aureus strains have an important role in the dissemination of this bacterium. To investigate the presence of S. aureus in the throat and anterior nares, samples from 1,243 healthy volunteers in a Mexican community were examined. The percentage of healthy carriers was 59.8%. Results showed that colonization of the throat occurred more frequently than that of the nares (46.5% versus 37.1%, P < 0.0001). Of the S. aureus carriers, 22.2% were exclusive nasal carriers and 38% were exclusive throat carriers. A total of 1,039 strains were isolated; 12.6% were shown to be methicillin-resistant S. aureus (MRSA). Of MRSA strains, 32.1% were isolated from exclusive throat carriers. Most of the strains isolated from the anterior nares and throat of the same carriers were the same or related; however, some were different. Pulsed-field gel electrophoresis (PFGE) pattern analysis of the MRSA strains isolated from the exclusive nasal carriers or exclusive throat carriers showed that they belong to different clusters. A 6-year prospective study was performed to investigate the persistence of S. aureus in the throat. Results showed that 13% of subjects were persistent carriers. Most of them were colonized with the same clone of S. aureus throughout the time of the study, and just three had different clones. Antimicrobial susceptibility testing showed that 91.1% of the strains were penicillin resistant. The presence of mecA and nucA genes (in order to confirm methicillin resistance) and of thermostable nuclease of S. aureus was examined. This study showed that some strains of S. aureus regularly colonized the throats of healthy people and could persist for years. PMID:20335416

  7. Sore throat in primary care project: a clinical score to diagnose viral sore throat.

    PubMed

    Mistik, Selcuk; Gokahmetoglu, Selma; Balci, Elcin; Onuk, Fahri A

    2015-06-01

    Viral agents cause the majority of sore throats. However, there is not currently a score to diagnose viral sore throat. The aims of this study were (i) to find the rate of bacterial and viral causes, (ii) to show the seasonal variations and (iii) to form a new scoring system to diagnose viral sore throat. A throat culture for group A beta haemolytic streptococci (GABHS) and a nasopharyngeal swab to detect 16 respiratory viruses were obtained from each patient. Over a period of 52 weeks, a total of 624 throat cultures and polymerase chain reaction analyses were performed. Logistic regression analysis was performed to find the clinical score. Viral infection was found in 277 patients (44.3%), and GABHS infection was found in 116 patients (18.5%). An infectious cause was found in 356 patients (57.1%). Rhinovirus was the most commonly detected infectious agent overall (highest in November, 34.5%), and the highest GABHS rate was in November (32.7%). Analysis of data provided a scoring system, called the Mistik Score, to diagnose viral sore throat. The predictive model for positive viral analysis included the following variables: absence of headache, stuffy nose, sneezing, temperature of ≥37.5°C on physical examination, and the absence of tonsillar exudate and/or swelling. The probability of a positive viral analysis for a score of 5 was 82.1%. The Mistik Score may be useful to diagnose viral sore throat. We suggest its use either alone or in combination with the Modified Centor Score. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. A Reappraisal of the Minimum Duration of Antibiotic Treatment Before Approval of Return to School for Children With Streptococcal Pharyngitis.

    PubMed

    Schwartz, Richard H; Kim, Danica; Martin, Michael; Pichichero, Michael E

    2015-12-01

    To determine whether a single dose of amoxicillin administered to a symptomatic child with confirmed strep throat might allow the child to return to school as little as 12 hours later. We enrolled 111 evaluable children with sore throat plus a positive streptococcal rapid antigen detection test (RADT) as well as a positive result for group A Streptococci (GAS). After throat swab specimens were obtained, all participants received a single dose of amoxicillin (50 mg/kg). Twelve to 23 hours after the first dose of amoxicillin, all participants returned in the morning of day 2 for a second throat swab specimen. At the day 2 visit, a nurse or medical assistant obtained an interval history, tympanic membrane temperature, and a pediatrician or nurse practitioner examined the oropharynx. On the morning of day 2, only 10 of 111 participants continued to have a positive RADT result, confirmed by overnight throat culture. GAS were not detectable on the day 2 throat specimen by RADT and also by culture in 91% of the study participants (confidence interval: 86-96%). Seven of 10 failures had a marked decrease in number of β-hemolytic colonies, which were 3+ to 4+ on the initial overnight culture plate and decreased to 1+ on the follow-up (obtained on day 2) throat culture plate. Two participants continued to have 3+ or 4+ GAS after incubation of the second throat culture specimen. Even in the late afternoon, a full dose of amoxicillin (50 mg/kg) administered after notification of positive RADT results for GAS resulted in nondetection of GAS in 91% of children the next morning. All children treated with amoxicillin for "strep throat" by 5 PM of day 1 may, if afebrile and improved, attend school on day 2.

  9. 21 CFR 874.4420 - Ear, nose, and throat manual surgical instrument.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... device includes the esophageal dilator; tracheal bistour (a long, narrow surgical knife); tracheal dilator; tracheal hook; laryngeal injection set; laryngeal knife; laryngeal saw; laryngeal trocar...; wire ear loop; microrule; mirror; mobilizer; ear, nose, and throat punch; ear, nose and throat knife...

  10. High-pressure-assisted design of porous topological semimetal carbon for Li-ion battery anode with high-rate performance

    NASA Astrophysics Data System (ADS)

    Liu, Junyi; Wang, Shuo; Qie, Yu; Zhang, Cunzhi; Sun, Qiang

    2018-02-01

    It has been a great challenge to develop a high-rate anode material with high-capacity, fast Li-ions diffusion and long cycling life going beyond the commercially used graphite in Li-ion battery. Here for the first time we propose a strategy combined high-pressure synthesis method with the global structure search to find a topological semimetal porous carbon as the desired anode. Our crystal-structure searching shows that we can obtain the ground state of an orthorhombic phase Li C6 with regular pores at 30 GPa, and when the Li atoms are removed, the resulting carbon structure is the recently predicted interlocked graphene network (IGN) that is a topological semimetal with an intrinsic high electronic conductivity. Based on the state-of-the-art first-principles calculations, we further find that the Li-ion migration energy barrier in the IGN is extremely low and the estimated diffusion coefficient can reach a magnitude of 10-4c m2/s at both low and high Li concentrations, which is three orders of magnitude larger than that of graphite anode. Moreover, the volume changes during the Li insertion and deinsertion are smaller than 3.2 % , while the theoretical specific capacity is the same as that of graphite anode. Our studies not only suggest a practical way of synthesizing the topological semimetal carbon but also propose a new anode material for Li-ion battery.

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

    Friedmann, T.A.; Tallant, D.R.; Barbour, J.C.

    Carbon Nitride (CN{sub x}) films have been grown by ion-assisted pulsed-laser deposition (IAPLD). Graphite targets were laser ablated while bombarding the substrate with ions from a broad-beam Kaufman-type ion source. Ion voltage, current density, substrate temperature, and feed gas composition (N{sub 2} in Ar) were varied. Resultant films were characterized by Raman. Fourier transform infrared (FTIR), and Rutherford back scattering (RBS) spectroscopy. Samples with {approximately} 30% N/C ratio have been fabricated. The corresponding Raman and FTIR spectra indicate that nitrogen is incorporated into the samples by insertion into sp{sup 2}-bonded structures. A low level of C{identical_to}N triple bonds is alsomore » found. As the ion current and voltage are increased with a pure Ar ion beam, Raman peaks associated with nanocrystalline graphite appear in the spectra. Adding low levels of nitrogen to the ion beam first reduces the Raman intensity in the vicinity of the graphite disorder peak without adding detectable amounts of nitrogen to the films (as measured by RBS). At higher nitrogen levels in the ion beam, significant amounts of nitrogen are incorporated into the samples, and the magnitude of the ``disorder`` peak increases. By increasing the temperature of the substrate during deposition, the broad peak due mainly to sp{sup 2}-bonded C-N in the FTIR spectra is shifted to lower wavenumber. This could be interpreted as evidence of single-bonded C-N; however, it is more likely that the character of the sp{sup 2} bonding is changing.« less

  12. Red-throated loons (Gavia stellata) breeding in Alaska, USA, are exposed to PCBs while on their Asian wintering grounds

    USGS Publications Warehouse

    Schmutz, J.A.; Trust, K.A.; Matz, A.C.

    2009-01-01

    Red-throated loons (Gavia stellata) breeding in Alaska declined 53% during 1977-1993. We compare concentrations of environmental contaminants in red-throated loons among four nesting areas in Alaska and discuss potential ramifications of exposure on reproductive success and population trends. Eggs from the four areas had similar total polychlorinated biphenyl (PCB) concentrations, but eggs from the Arctic coastal plain had different congener profiles and greater toxic equivalents (TEQs) than eggs from elsewhere. Satellite telemetry data indicate that red-throated loons from the Arctic coastal plain in northern Alaska winter in southeast Asia, while those breeding elsewhere in Alaska winter in North America. Different wintering areas may lead to differential PCB accumulation among red-throated loon populations. For eggs from the Arctic coastal plain, TEQs were great enough to postulate PCB-associated reproductive effects in piscivores. The correlation between migration patterns and PCB profiles suggests that red-throated loons breeding in northern Alaska are exposed to PCBs while on their Asian wintering grounds.

  13. Estimation of the Human Extrathoracic Deposition Fraction of Inhaled Particles Using a Polyurethane Foam Collection Substrate in an IOM Sampler.

    PubMed

    Sleeth, Darrah K; Balthaser, Susan A; Collingwood, Scott; Larson, Rodney R

    2016-03-07

    Extrathoracic deposition of inhaled particles (i.e., in the head and throat) is an important exposure route for many hazardous materials. Current best practices for exposure assessment of aerosols in the workplace involve particle size selective sampling methods based on particle penetration into the human respiratory tract (i.e., inhalable or respirable sampling). However, the International Organization for Standardization (ISO) has recently adopted particle deposition sampling conventions (ISO 13138), including conventions for extrathoracic (ET) deposition into the anterior nasal passage (ET₁) and the posterior nasal and oral passages (ET₂). For this study, polyurethane foam was used as a collection substrate inside an inhalable aerosol sampler to provide an estimate of extrathoracic particle deposition. Aerosols of fused aluminum oxide (five sizes, 4.9 µm-44.3 µm) were used as a test dust in a low speed (0.2 m/s) wind tunnel. Samplers were placed on a rotating mannequin inside the wind tunnel to simulate orientation-averaged personal sampling. Collection efficiency data for the foam insert matched well to the extrathoracic deposition convention for the particle sizes tested. The concept of using a foam insert to match a particle deposition sampling convention was explored in this study and shows promise for future use as a sampling device.

  14. Estimation of the Human Extrathoracic Deposition Fraction of Inhaled Particles Using a Polyurethane Foam Collection Substrate in an IOM Sampler

    PubMed Central

    Sleeth, Darrah K.; Balthaser, Susan A.; Collingwood, Scott; Larson, Rodney R.

    2016-01-01

    Extrathoracic deposition of inhaled particles (i.e., in the head and throat) is an important exposure route for many hazardous materials. Current best practices for exposure assessment of aerosols in the workplace involve particle size selective sampling methods based on particle penetration into the human respiratory tract (i.e., inhalable or respirable sampling). However, the International Organization for Standardization (ISO) has recently adopted particle deposition sampling conventions (ISO 13138), including conventions for extrathoracic (ET) deposition into the anterior nasal passage (ET1) and the posterior nasal and oral passages (ET2). For this study, polyurethane foam was used as a collection substrate inside an inhalable aerosol sampler to provide an estimate of extrathoracic particle deposition. Aerosols of fused aluminum oxide (five sizes, 4.9 µm–44.3 µm) were used as a test dust in a low speed (0.2 m/s) wind tunnel. Samplers were placed on a rotating mannequin inside the wind tunnel to simulate orientation-averaged personal sampling. Collection efficiency data for the foam insert matched well to the extrathoracic deposition convention for the particle sizes tested. The concept of using a foam insert to match a particle deposition sampling convention was explored in this study and shows promise for future use as a sampling device. PMID:26959046

  15. Survival of adult Red-throated Loons (Gavia stellata) may be linked to marine conditions

    USGS Publications Warehouse

    Schmutz, Joel A.

    2014-01-01

    Large variations in the summering population size of Red-throated Loons (Gavia stellata) have occurred in recent decades in Alaska. Little information exists about annual or seasonal survival rates of adult Red-throated Loons. This study used tracking data from satellite transmitters implanted into 33 Red-throated Loons captured on breeding areas in Alaska to estimate annual survival with the sampling effort split between two study periods: 2000–2002 and 2008–2010. Mortality was inferred from transmitted sensor data that indicated body temperature of the Red-throated Loon and voltage of the transmitter's battery. Two definitive mortalities occurred, resulting in an annual survival estimate of 0.920 (SE = 0.054). The fates of two additional Red-throated Loons were ambiguous and, when treated as mortalities, the annual survival estimate was 0.838 (SE = 0.074). All four putative mortalities occurred during the non-breeding season in the early study period. Oceanic conditions, indexed by the Pacific Decadal Oscillation, appeared to differ between the study periods with higher Pacific Decadal Oscillation values associated with the early study period. Given that high values for Pacific Decadal Oscillation were also associated with the large decline of Red-throated Loons observed in Alaska during 1977–1993, this study suggests that survival of adult Red-throated Loons may vary in relation to the state of the marine ecosystem and thus contribute to long-term variation in population trends.

  16. Comparison of Effectiveness of Betamethasone gel Applied to the Tracheal Tube and IV Dexamethasone on Postoperative Sore Throat: A Randomized Controlled Trial

    PubMed Central

    Tabari, Masoomeh; Soltani, Ghasem; Zirak, Nahid; Alipour, Mohammad; Khazaeni, Kamran

    2013-01-01

    Introduction: Postoperative sore throat is a common complaint in patients with endotracheal intubation and has potentially dangerous complications. This randomized controlled trial study investigated the incidence of postoperative sore throat after general anesthesia when betamethasone gel is applied to a tracheal tube compared with when IV dexamethasone is prescribed. Materials and Methods: Two hundred and twenty five American Society of Anesthesiologist (ASA)-class I and II patients undergoing elective abdominal surgery with tracheal intubation were randomly divided into three groups: betamethasone gel, intravenous (IV) dexamethasone, and control groups. In the post-anesthesia care unit, a blinded anesthesiologist interviewed all patients regarding postoperative sore throat at 1,6, and 24 hours after surgery. Results: The incidence of sore throat was significantly lower in the betamethasone gel group compared with the IV dexamethasone and control groups, 1, 6, and 24 hours after surgery. In the first day after surgery 10.7% of the betamethasone group had sore throat whereas 26.7% of the IV dexamethasone group and 30.7% of the control group had sore throat. Bucking before extubation was observed in 14(18.4%), 8(10.4%), and 9(12.2%) patients, in the IV dexamethasone, betamethasone gel, and control group, respectively. Conclusion: We concluded that wide spread application of betamethasone gel over tracheal tubes effectively mitigates postoperative sore throat, compared with IV dexamethasone application. PMID:24303443

  17. Characterization of real objects by an active electrolocation sensor

    NASA Astrophysics Data System (ADS)

    Metzen, Michael G.; Al Ghouz, Imène; Krueger, Sandra; Bousack, Herbert; von der Emde, Gerhard

    2012-04-01

    Weakly electric fish use a process called 'active electrolocation' to orientate in their environment and to localize objects based on their electrical properties. To do so, the fish discharge an electric organ which emits brief electrical current pulses (electric organ discharge, EOD) and in return sense the generated electric field which builds up surrounding the animal. Caused by the electrical properties of nearby objects, fish measure characteristic signal modulations with an array of electroreceptors in their skin. The fish are able to gain important information about the geometrical properties of an object as well as its complex impedance and its distance. Thus, active electrolocation is an interesting feature to be used in biomimetic approaches. We used this sensory principle to identify different insertions in the walls of Plexiglas tubes. The insertions tested were composed of aluminum, brass and graphite in sizes between 3 and 20 mm. A carrier signal was emitted and perceived with the poles of a commercial catheter for medical diagnostics. Measurements were performed with the poles separated by 6.3 to 55.3 mm. Depending on the length of the insertion in relation to the sender-receiver distance, we observed up to three peaks in the measured electric images. The first peak was affected by the material of the insertion, while the distance between the second and third peak strongly correlated with the length of the insertion. In a second experiment we tested whether various materials could be detected by using signals of different frequency compositions. Based on their electric images we were able to discriminate between objects having different resistive properties, but not between objects of complex impedances.

  18. Variable flow gas turbine engine

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

    Stroem, S.

    1986-11-25

    This patent describes a variable flow gas turbine engine of the type having a combustor for generating combustion gases and a turbine rotor for receiving and expanding the hot combustion gases, comprising: duct means for defining a channel for directing the flow of combustion gases from the combustor to the rotor; vane means in the channel forming at least one throat; means for varying the effective flow area for combustion gases flowing through the throat and impinging on the rotor. The varying means includes winglet means fixedly mounted in the throat for separating the gases flowing through the throat intomore » first and second streams; and means for injecting high pressure fluid into the throat for varying the flow of combustion gases in one of the streams.« less

  19. Stakeholders' views of recurrent sore throat, tonsillitis and their management: a qualitative interview study for the NAtional Trial of Tonsillectomy IN Adults (NATTINA Part 1).

    PubMed

    McSweeney, L A; Rousseau, N S; Wilson, J A; Wilkes, S; Haighton, C A

    2017-04-01

    To determine the impact of recurrent sore throats and tonsillitis in adults and stakeholder views of treatment pathways. Qualitative semistructured interview design reporting novel data from a feasibility study for a UK national trial of tonsillectomy in adults. Nine study sites linked to ear, nose and throat departments in National Health Service hospitals located across the United Kingdom. Fifteen patients, 11 general practitioners and 22 ear, nose and throat staff consented to in-depth interviews, which were analysed using a framework analysis approach. Views of stakeholder groups. Recurrent sore throats were reported to severely impact patients' family, work and social life. Ear, nose and throat staff stated that patients faced increasing barriers to secondary care service access. General practitioners were under pressure to reduce 'limited clinical value' surgical procedures. The findings from this study suggest that there is a disconnect between the attitudes of the stakeholders and the reality of recurrent sore throat, tonsillectomy procedures and service provision. More evidence for the role of tonsillectomy is needed from randomised controlled trials to determine whether it should continue to be ranked as a procedure of limited clinical effectiveness. © 2016 John Wiley & Sons Ltd.

  20. The effectiveness of the McIsaac clinical decision rule in the management of sore throat: an evaluation from a pediatrics ward.

    PubMed

    Thillaivanam, Saravanapriya; Amin, Arwa M; Gopalakrishnan, Sheila; Ibrahim, Baharudin

    2016-10-01

    Sore throats may be due to either viral or group A beta hemolytic streptococcus (GABHS) infections; but diagnosis of the etiology of a sore throat is difficult, often leading to unnecessary antibiotic prescriptions and consequent increases in bacterial resistance. Scoring symptoms using the McIsaac clinical decision rule can help physicians to diagnose and manage streptococcal infections leading to sore throat and have been recommended by the Ministry of Health, Malaysia. In this paper, we offer the first assessment of the effectiveness of the McIsaac rule in a clinical setting in Malaysia. This study is a retrospective review of 116 pediatric patients presenting with sore throat. Group A comprised patients before the implementation of the McIsaac rule and Group B comprised patients after the implementation. Unnecessary throat swab cultures were reduced by 40% (P = 0.003). Redundant antibiotic prescriptions were reduced by 26.5% (P = 0.003) and the overall use of antibiotics was reduced by 22.1% (P = 0.003). The pediatricians' compliance rate to McIsaac rule criteria was 45% before implementation of the McIsaac rule, but improved to 67.9% (P = 0.0005) after implementation. The McIsaac rule is an effective tool for the management of sore throat in children in Malaysia.

  1. Improvements in throat function and qualities of sore throat from locally applied flurbiprofen 8.75 mg in spray or lozenge format: findings from a randomized trial of patients with upper respiratory tract infection in the Russian Federation

    PubMed Central

    Burova, Natalia; Bychkova, Valeria; Shephard, Adrian

    2018-01-01

    Objective To assess the speed of relief provided by flurbiprofen 8.75 mg spray and lozenge and their effect on many of the different qualities and characteristics of throat pain and discomfort, and the many articulations of the broad term “sore throat” (ST). Patients and methods Four hundred and forty adults with recent-onset, moderate-to-severe ST due to upper respiratory tract infection (URTI) were randomized to a single dose of either flurbiprofen 8.75 mg spray (n=218) or flurbiprofen 8.75 mg lozenge (n=222). Throat swabs for bacterial culture were taken at baseline. ST relief was assessed at 1 minute, 1 and 2 hours post-dose using the Sore Throat Relief Rating Scale. The change from baseline at 1 and 2 hours post-dose in difficulty swallowing and swollen throat was assessed using the difficulty swallowing scale and the swollen throat scale, respectively. Patients’ experience of URTI symptoms was assessed using a URTI questionnaire at baseline and 2 hours post-dose. The change in Qualities of Sore Throat Index, a 10-item index of qualities of ST, from baseline at 2 hours post-dose was also measured. Results ST relief was evident in the spray and the lozenge treatment groups at 1 minute, 1 and 2 hours post-dose (P>0.05). In both groups, scores for difficulty swallowing and swollen throat significantly improved at 1 and 2 hours post-dose compared with baseline. At 2 hours post-dose, the number of patients experiencing URTI symptoms that can be attributed to or associated with ST decreased relative to baseline. The mean change from baseline to 2 hours post-dose for each individual score on the Qualities of Sore Throat Index showed significant improvements for flurbiprofen spray and lozenge (all P<0.0001). Conclusion Non-inferiority was established, and flurbiprofen spray and lozenge provided effective relief from ST pain and many of the other commonly reported qualities of ST.

  2. Tonsillectomy Versus Watchful Waiting for Recurrent Throat Infection: A Systematic Review

    PubMed Central

    Morad, Anna; Sathe, Nila A.; Francis, David O.; McPheeters, Melissa L.

    2017-01-01

    CONTEXT: The effectiveness of tonsillectomy or adenotonsillectomy (“tonsillectomy”) for recurrent throat infection compared with watchful waiting is uncertain. OBJECTIVE: To compare sleep, cognitive, behavioral, and health outcomes of tonsillectomy versus watchful waiting in children with recurrent throat infections. DATA SOURCES: MEDLINE, Embase, and the Cochrane Library. STUDY SELECTION: Two investigators independently screened studies against predetermined criteria. DATA EXTRACTION: One investigator extracted data with review by a second. Investigators independently assessed risk of bias and strength of evidence (SOE) and confidence in the estimate of effects. RESULTS: Seven studies including children with ≥3 infections in the previous 1 to 3 years addressed this question. In studies reporting baseline data, number of infections/sore throats decreased from baseline in both groups, with greater decreases in sore throat days, clinician contacts, diagnosed group A streptococcal infections, and school absences in tonsillectomized children in the short term (<12 months). Quality of life was not markedly different between groups at any time point. LIMITATIONS: Few studies fully categorized infection/sore throat severity; attrition was high. CONCLUSIONS: Throat infections, utilization, and school absences improved in the first postsurgical year in tonsillectomized children versus children not receiving surgery. Benefits did not persist over time; longer-term outcomes are limited. SOE is moderate for reduction in short-term throat infections and insufficient for longer-term reduction. SOE is low for no difference in longer-term streptococcal infection reduction. SOE is low for utilization and missed school reduction in the short term, low for no difference in longer-term missed school, and low for no differences in quality of life. PMID:28096515

  3. Tonsillectomy Versus Watchful Waiting for Recurrent Throat Infection: A Systematic Review.

    PubMed

    Morad, Anna; Sathe, Nila A; Francis, David O; McPheeters, Melissa L; Chinnadurai, Sivakumar

    2017-02-01

    The effectiveness of tonsillectomy or adenotonsillectomy ("tonsillectomy") for recurrent throat infection compared with watchful waiting is uncertain. To compare sleep, cognitive, behavioral, and health outcomes of tonsillectomy versus watchful waiting in children with recurrent throat infections. MEDLINE, Embase, and the Cochrane Library. Two investigators independently screened studies against predetermined criteria. One investigator extracted data with review by a second. Investigators independently assessed risk of bias and strength of evidence (SOE) and confidence in the estimate of effects. Seven studies including children with ≥3 infections in the previous 1 to 3 years addressed this question. In studies reporting baseline data, number of infections/sore throats decreased from baseline in both groups, with greater decreases in sore throat days, clinician contacts, diagnosed group A streptococcal infections, and school absences in tonsillectomized children in the short term (<12 months). Quality of life was not markedly different between groups at any time point. Few studies fully categorized infection/sore throat severity; attrition was high. Throat infections, utilization, and school absences improved in the first postsurgical year in tonsillectomized children versus children not receiving surgery. Benefits did not persist over time; longer-term outcomes are limited. SOE is moderate for reduction in short-term throat infections and insufficient for longer-term reduction. SOE is low for no difference in longer-term streptococcal infection reduction. SOE is low for utilization and missed school reduction in the short term, low for no difference in longer-term missed school, and low for no differences in quality of life. Copyright © 2017 by the American Academy of Pediatrics.

  4. 21 CFR 874.4250 - Ear, nose, and throat electric or pneumatic surgical drill.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... surgical drill. 874.4250 Section 874.4250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH....4250 Ear, nose, and throat electric or pneumatic surgical drill. (a) Identification. An ear, nose, and throat electric or pneumatic surgical drill is a rotating drilling device, including the handpiece, that...

  5. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... laser. 874.4500 Section 874.4500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND..., nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and throat microsurgical carbon dioxide laser is a device intended for the surgical excision of tissue from the ear, nose...

  6. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... laser. 874.4500 Section 874.4500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND..., nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and throat microsurgical carbon dioxide laser is a device intended for the surgical excision of tissue from the ear, nose...

  7. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... laser. 874.4500 Section 874.4500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND..., nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and throat microsurgical carbon dioxide laser is a device intended for the surgical excision of tissue from the ear, nose...

  8. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... laser. 874.4500 Section 874.4500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND..., nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and throat microsurgical carbon dioxide laser is a device intended for the surgical excision of tissue from the ear, nose...

  9. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... laser. 874.4500 Section 874.4500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND..., nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and throat microsurgical carbon dioxide laser is a device intended for the surgical excision of tissue from the ear, nose...

  10. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat drug administration device. 874.5220 Section 874.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose...

  11. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat drug administration device. 874.5220 Section 874.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose...

  12. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat drug administration device. 874.5220 Section 874.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose...

  13. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat examination and treatment unit. 874.5300 Section 874.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300...

  14. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat drug administration device. 874.5220 Section 874.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose...

  15. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat examination and treatment unit. 874.5300 Section 874.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300...

  16. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat examination and treatment unit. 874.5300 Section 874.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300...

  17. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat drug administration device. 874.5220 Section 874.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose...

  18. Brown-headed Cowbird parasitism of the Black-throated Sparrow in central Arizona

    USGS Publications Warehouse

    Johnson, M.J.; van Riper, Charles

    2004-01-01

    From 1994-1996 we investigated effects of Brown-headed Cowbird (Molothrus ater) parasitism on Black-throated Sparrow (Amphispiza bilineata) nesting success in the Verde Valley of central Arizona. Of 56 Black-throated Sparrow nests, 52% were parasitized. Black-throated Sparrows appear to respond to natural parasitism by accepting the cowbird egg, deserting the nest, or burying the cowbird egg. Removal and damage of host eggs by female cowbirds effectively reduced clutch size from an average of 3.4 to 1.9 eggs. Because of this reduced clutch size, Black-throated Sparrow reproductive success was significantly lower in parasitized nests (0.2 young fledged/ nest) as compared to nonparasitized nests (1.6 young fledged/nest). When comparing cowbird parasitism between two habitat types, we found significantly higher parasitism frequencies in crucifixion-thorn (Canotia holacantha) versus creosote-bush (Larrea divaricata) habitat. We argue that this difference in parasitism is due to the greater number of tall perches (e.g., shrubs >4 m) available in crucifixion-thorn habitat, providing vantage points for female cowbirds to better find Black-throated Sparrow nests.

  19. Dual throat engine design for a SSTO launch vehicle

    NASA Technical Reports Server (NTRS)

    Obrien, C. J.; Salmon, J. W.

    1980-01-01

    A propulsion system analysis of a dual fuel, dual throat engine for launch vehicle application was conducted. Basic dual throat engine characterization data are presented to allow vehicle optimization studies to be conducted. A preliminary baseline engine system was defined. Dual throat engine performance, envelope, and weight parametric data were generated over the parametric range of thrust from 890 to 8896 KN (200K to 2M lb-force), chamber pressure from 6.89 million to 34.5 million N/sq m (1000 to 5000 psia) thrust ratio from 1.2 to 5, and a range of mixture ratios for the two tripropellant combinations: LO2/RP-1 + LH2 and LO2/LCH4 + LH2. The results of the study indicate that the dual fuel dual throat engine is a viable single stage to orbit candidate.

  20. Pressure distribution in a converging-diverging nozzle during two-phase choked flow of subcooled nitrogen

    NASA Technical Reports Server (NTRS)

    Simoneau, R. J.

    1975-01-01

    Choked flow rates and axial pressure distributions were measured for subcooled nitrogen in a converging-diverging nozzle with a constant area section in the throat region. Stagnation pressures ranged from slightly above saturation to twice the thermodynamic critical pressure. Stagnation temperatures ranged from 0.75 to 1.03 times the thermodynamic critical temperature. The choking plane is at the divergence end of the constant area throat section. At high stagnation pressures the fluid stays liquid well into the constant area throat region; at near saturation stagnation pressures it appears that vaporization occurs at or before the entrance to the constant area throat region. The throat-to-stagnation pressure ratio data exhibits an anomalous flat region, and this anomaly is related to the two-phase process. The fluid is metastably all liquid below the saturation pressure.

  1. Post-intubation sore throat and menstruation cycles.

    PubMed

    Orandi, Amirali; Orandi, Amirhossein; Najafi, Atabak; Hajimohammadi, Fatemeh; Soleimani, Sara; Zahabi, Somayeh

    2013-09-01

    Postoperative sore throat is one of the most common complications of general anesthesia and intubation with prevalence of 18%-65% in different studies. Several risk factors including female gender, postoperative nausea and vomiting and so on have been mentioned. The aim of this study was to evaluate the incidence of postoperative sore throat in females and its association with menstrual cycles. One hundred females between 18-45 years old with ASA class I or II without predicted difficult airway that were candidate for operation in supine position were enrolled in study. Patients who had pulmonary disease, smoking, common cold within two weeks prior to the operation, previous traumatic intubation history, removable dentures, any congenital or acquired deformity in face, neck, mouth and airway, any known pathology in mouth like aphthous and mouth ulcer,pregnant women, and patients with irregular cycles, and those taking oral contraceptive pills were excluded. By the same protocol general anesthesia was provided and the patients were asked to fill out a three-point scale questionnaire (Low, High, None) 1,6 and 24 hours following intubation to study and record the incidence and severity of sore throat, dysphagia and hoarseness. The date of last menstrual period had been recorded as well. Of 100 patients, in the first six hours, 51 patients had sore throat and 49 had no pain. During the first 6 hours, 33 patients (33%) had dysphagia and 13 patients had hoarseness at 6th postoperative hour. Age, weight, LMP, intubation time, operation and extubation time and coughing were compared to sore throat, dysphagia and hoarseness. The association between the incidence of coughing and bucking and sore throat was significant (P = 0.03). None of the parameters had a statistically meaningful association with dysphagia. According to our results, by omitting probable risk factors of incidence of sore throat and evaluation of role of hormonal changes in women represented in menstrual cycles, there was no significant association between menstrual cycle and sore throat incidence.

  2. Multiscale Pore Throat Network Reconstruction of Tight Porous Media Constrained by Mercury Intrusion Capillary Pressure and Nuclear Magnetic Resonance Measurements

    NASA Astrophysics Data System (ADS)

    Xu, R.; Prodanovic, M.

    2017-12-01

    Due to the low porosity and permeability of tight porous media, hydrocarbon productivity strongly depends on the pore structure. Effective characterization of pore/throat sizes and reconstruction of their connectivity in tight porous media remains challenging. Having a representative pore throat network, however, is valuable for calculation of other petrophysical properties such as permeability, which is time-consuming and costly to obtain by experimental measurements. Due to a wide range of length scales encountered, a combination of experimental methods is usually required to obtain a comprehensive picture of the pore-body and pore-throat size distributions. In this work, we combine mercury intrusion capillary pressure (MICP) and nuclear magnetic resonance (NMR) measurements by percolation theory to derive pore-body size distribution, following the work by Daigle et al. (2015). However, in their work, the actual pore-throat sizes and the distribution of coordination numbers are not well-defined. To compensate for that, we build a 3D unstructured two-scale pore throat network model initialized by the measured porosity and the calculated pore-body size distributions, with a tunable pore-throat size and coordination number distribution, which we further determine by matching the capillary pressure vs. saturation curve from MICP measurement, based on the fact that the mercury intrusion process is controlled by both the pore/throat size distributions and the connectivity of the pore system. We validate our model by characterizing several core samples from tight Middle East carbonate, and use the network model to predict the apparent permeability of the samples under single phase fluid flow condition. Results show that the permeability we get is in reasonable agreement with the Coreval experimental measurements. The pore throat network we get can be used to further calculate relative permeability curves and simulate multiphase flow behavior, which will provide valuable insights into the production optimization and enhanced oil recovery design.

  3. Constraints on wrapped Dirac-Born-Infeld inflation in a warped throat

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

    Kobayashi, Takeshi; Mukohyama, Shinji; Kinoshita, Shunichiro, E-mail: tkobayashi@utap.phys.s.u-tokyo.ac.jp, E-mail: mukoyama@phys.s.u-tokyo.ac.jp, E-mail: kinoshita@utap.phys.s.u-tokyo.ac.jp

    2008-01-15

    We derive constraints on the tensor to scalar ratio and on the background charge of the warped throat for Dirac-Born-Infeld inflation driven by D5- and D7-branes wrapped over cycles of the throat. It is shown that background charge well beyond the known maximal value is required in most cases for Dirac-Born-Infeld inflation to generate cosmological observables compatible with the WMAP3 (Wilkinson Microwave Anisotropy Probe 3) data. Most of the results derived in this paper are insensitive to the details of the inflaton potential, and could be applied to generic warped throats.

  4. Optimizing Naval Hospital Camp Pendleton’s Primary Care Access by Managing Demand of the Emergency Department through a Health Services Center: A Marcus Welby Care Initiative

    DTIC Science & Technology

    2006-06-01

    10 strep throat . I want to order a throat culture and start you on some antibiotics." As quickly as the doctor appeared, he was gone, moving on to the...TRICARE Prime. She wakes up one morning with an awful sore throat and difficulty swallowing. She tries to contact her Primary Care Manager (PCM) by...next of what seemed a never ending stream of patients. After the throat culture and an additional hour wait at the pharmacy, Mrs. Smith is on her way

  5. Optimization of Tape Winding Process Parameters to Enhance the Performance of Solid Rocket Nozzle Throat Back Up Liners using Taguchi's Robust Design Methodology

    NASA Astrophysics Data System (ADS)

    Nath, Nayani Kishore

    2017-08-01

    The throat back up liners is used to protect the nozzle structural members from the severe thermal environment in solid rocket nozzles. The throat back up liners is made with E-glass phenolic prepregs by tape winding process. The objective of this work is to demonstrate the optimization of process parameters of tape winding process to achieve better insulative resistance using Taguchi's robust design methodology. In this method four control factors machine speed, roller pressure, tape tension, tape temperature that were investigated for the tape winding process. The presented work was to study the cogency and acceptability of Taguchi's methodology in manufacturing of throat back up liners. The quality characteristic identified was Back wall temperature. Experiments carried out using L 9 ' (34) orthogonal array with three levels of four different control factors. The test results were analyzed using smaller the better criteria for Signal to Noise ratio in order to optimize the process. The experimental results were analyzed conformed and successfully used to achieve the minimum back wall temperature of the throat back up liners. The enhancement in performance of the throat back up liners was observed by carrying out the oxy-acetylene tests. The influence of back wall temperature on the performance of throat back up liners was verified by ground firing test.

  6. Nozzle Aerodynamic Stability During a Throat Shift

    NASA Technical Reports Server (NTRS)

    Kawecki, Edwin J.; Ribeiro, Gregg L.

    2005-01-01

    An experimental investigation was conducted on the internal aerodynamic stability of a family of two-dimensional (2-D) High Speed Civil Transport (HSCT) nozzle concepts. These nozzles function during takeoff as mixer-ejectors to meet acoustic requirements, and then convert to conventional high-performance convergent-divergent (CD) nozzles at cruise. The transition between takeoff mode and cruise mode results in the aerodynamic throat and the minimum cross-sectional area that controls the engine backpressure shifting location within the nozzle. The stability and steadiness of the nozzle aerodynamics during this so called throat shift process can directly affect the engine aerodynamic stability, and the mechanical design of the nozzle. The objective of the study was to determine if pressure spikes or other perturbations occurred during the throat shift process and, if so, identify the caused mechanisms for the perturbations. The two nozzle concepts modeled in the test program were the fixed chute (FC) and downstream mixer (DSM). These 2-D nozzles differ principally in that the FC has a large over-area between the forward throat and aft throat locations, while the DSM has an over-area of only about 10 percent. The conclusions were that engine mass flow and backpressure can be held constant simultaneously during nozzle throat shifts on this class of nozzles, and mode shifts can be accomplished at a constant mass flow and engine backpressure without upstream pressure perturbations.

  7. Fractal Characteristics of the Pore Network in Diatomites Using Mercury Porosimetry and Image Analysis

    NASA Astrophysics Data System (ADS)

    Stańczak, Grażyna; Rembiś, Marek; Figarska-Warchoł, Beata; Toboła, Tomasz

    The complex pore space considerably affects the unique properties of diatomite and its significant potential for many industrial applications. The pore network in the diatomite from the Lower Miocene strata of the Skole nappe (the Jawornik deposit, SE Poland) has been investigated using a fractal approach. The fractal dimension of the pore-space volume was calculated using the Menger sponge as a model of a porous body and the mercury porosimetry data in a pore-throat diameter range between 10,000 and 10 nm. Based on the digital analyses of the two-dimensional images from thin sections taken under a scanning electron microscope at the backscattered electron mode at different magnifications, the authors tried to quantify the pore spaces of the diatomites using the box counting method. The results derived from the analyses of the pore-throat diameter distribution using mercury porosimetry have revealed that the pore space of the diatomite has the bifractal structure in two separated ranges of the pore-throat diameters considerably smaller than the pore-throat sizes corresponding to threshold pressures. Assuming that the fractal dimensions identified for the ranges of the smaller pore-throat diameters characterize the overall pore-throat network in the Jawornik diatomite, we can set apart the distribution of the pore-throat volume (necks) and the pore volume from the distribution of the pore-space volume (pores and necks together).

  8. Validity of rapid antigen detection testing in group A beta-hemolytic streptococcal tonsillopharyngitis.

    PubMed

    Küçük, Oznur; Biçer, Suat; Giray, Tuba; Cöl, Defne; Erdağ, Gülay Ciler; Gürol, Yeşim; Kaspar, Ciğdem E; Vitrinel, Ayça

    2014-02-01

    To evaluate the utility of rapid antigen detection testing (RADT) for the diagnosis of group A beta-hemolytic streptococcal tonsillopharyngitis in children, and to detect the sensitivity and specificity of rapid antigen detection of group A beta-hemolytic streptococci from throat specimen compared with throat culture. Rapid antigen detection and throat culture results for group A beta-hemolytic streptococci from outpatients attending university hospital between 1st January 2011 and 31st of December 2011 were evaluated retrospectively. The antigen test negative-throat culture positive patients were investigated for streptococcal carriage. For this purpose, the throat culture results taken from these patients were reviewed after treatment. Eight hundred and ninetytwo children were included in the studywith a mean age of 5.34 y. There were 639 and 253 children in two groups with age of 0-6 and 7-17 y, RADT sensitivity and specificity were found to be 59.5 % and 97.2 %, respectively. The positive predictive value was 87.1 %, whereas negative predictive value was 88.4 %. After treatment of 74 patients with throat culture positive and antigen test negative. Group A beta-hemolytic streptococci were isolated in 12 of them (16.2 %) and accepted as a carrier. The low sensitivity of the RADT may be related to streptococcal carriage in some patients. The throat culture should be repeated after treatment to detect streptococcal carriage.

  9. Streptococcal sore throat followup program in a hospital clinic, New York City.

    PubMed Central

    Kaufman, A; Murray, D; Starita, L; Brickner, P W

    1975-01-01

    To improve followup and treatment of patients with streptococcal sore throat at St. Vincent's Hospital and Medical Center, New York City, a simple and inexpensive method was devised for recalling and treating untreated patients with positive throat cultures and culturing household contacts. The program was conducted by a clinic nurse and a secretary, with only occasional assistance from a physician. All services were free for those without Medicaid coverage. The secretary sent notification letters to all patients with positive cultures urging them to return for treatment and emphasizing the need for their contacts to come for screening. The secretary, trained in the throat culturing technique, also performed the laboratory work on the cultures from contacts. The clinic nurse swabbed the throats of all contacts and administered treatment, according to a standing-order protocol, to all with culture-proved streptococcal sore throat. A comparison of initially untreated patients with positive cultures seen 3 months before and 6 months after the program was started revealed that 46 percent returned for treatment after the notification letter was sent; before the program only 21 percent returned for treatment. No attempt had been made to reach household contacts before the program began. The rate of streptococcal sore throat in contacts was 14 percent, and in the clinic patients it was 11 percent during the first 6 months of the program. Images p369-a p371-a PMID:808824

  10. Experimental evaluation of neural probe’s insertion induced injury based on digital image correlation method

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

    Zhang, Wenguang, E-mail: zhwg@sjtu.edu.cn; Ma, Yakun; Li, Zhengwei

    Purpose: The application of neural probes in clinic has been challenged by probes’ short lifetime when implanted into brain tissue. The primary goal is to develop an evaluation system for testing brain tissue injury induced by neural probe’s insertion using microscope based digital image correlation method. Methods: A brain tissue phantom made of silicone rubber with speckle pattern on its surface was fabricated. To obtain the optimal speckle pattern, mean intensity gradient parameter was used for quality assessment. The designed testing system consists of three modules: (a) load module for simulating neural electrode implantation process; (b) data acquisition module tomore » capture micrographs of speckle pattern and to obtain reactive forces during the insertion of the probe; (c) postprocessing module for extracting tissue deformation information from the captured speckle patterns. On the basis of the evaluation system, the effects of probe wedge angle, insertion speed, and probe streamline on insertion induced tissue injury were investigated. Results: The optimal quality speckle pattern can be attained by the following fabrication parameters: spin coating rate—1000 r/min, silicone rubber component A: silicone rubber component B: softener: graphite = 5 ml: 5 ml: 2 ml: 0.6 g. The probe wedge angle has a significant effect on tissue injury. Compared to wedge angle 40° and 20°, maximum principal strain of 60° wedge angle was increased by 40.3% and 87.5%, respectively; compared with a relatively higher speed (500 μm/s), the maximum principle strain within the tissue induced by slow insertion speed (100 μm/s) was increased by 14.3%; insertion force required by probe with convex streamline was smaller than the force of traditional probe. Based on the experimental results, a novel neural probe that has a rounded tip covered by a biodegradable silk protein coating with convex streamline was proposed, which has both lower insertion and micromotion induced tissue injury. Conclusions: The established evaluation system has provided a simulation environment for testing brain tissue injury produced by various insertion conditions. At the same time, it eliminates the adverse effect of biological factors on tissue deformation during the experiment, improving the repeatability of measurement results. As a result, the evaluation system will provide support on novel neural probe design that can reduce the acute tissue injury during the implantation of the probe.« less

  11. Interaction of Highly Underexpanded Jets with Simulated Lunar Surfaces

    NASA Technical Reports Server (NTRS)

    Stitt, Leonard E.

    1961-01-01

    Pressure distributions and erosion patterns on simulated lunar surfaces (hard and soft) and interference effects between the surface and two representative lunar vehicles (cylindrical and spherical) were obtained with cold-air jets at various descent heights and nozzle total-pressure ratios up to 288,000. Surface pressure distributions were dependent on both nozzle area ratio and, nozzle contour. Peak pressures obtained with a sonic nozzle agreed closely with those predicted theoretically for a near-sonic jet expanding into a vacuum. Short bell-shaped nozzles gave annular pressure distributions; the low center pressure resulted from the coalescence of shocks that originated within the nozzle. The high surface pressures were contained within a circle whose diameter was about 16 throat diameters, regardless of nozzle area ratio or contour. The peak pressure increased rapidly as the vehicle approached the surface; for example, at a descent height of 40 throat diameters the peak pressure was 0.4 percent of the chamber pressure, but increased to 6 percent at 13 throat diameters. The exhaust jet eroded a circular concave hole in white sand at descent heights from about 200 to 600 throat diameters. The hole diameter was about 225 throat diameters, while the depth was approximately 60 throat diameters. The sand particles, which formed a conical sheet at a semivertex angle of 50 deg, appeared to follow a ballistic trajectory and at no time struck the vehicle. An increase in pressure was measured on the base of the cylindrical lunar vehicle when it approached to within 14 throat diameters of the hard, flat surface. No interference effects were noted between the spherical model and the surface to descent heights as low as 8 throat diameters.

  12. Single bolus parecoxib attenuates sore throat after laryngeal microsurgery: a randomized double-blind control study.

    PubMed

    Huang, Hui-Fang; Chang, Pi-Ying; Chen, Yu-Chun; Tseng, Kuang-Yi; Hsu, Hung-Te; Cheng, Kuang-I; Lu, I-Cheng

    2014-11-01

    Laryngeal microsurgery is performed to assess disorders of the larynx. Parecoxib is the only parenterally administered selective cyclooxygenase (COX)-2 inhibitor widely used in acute pain control. The purpose of this study is to assess the analgesic effects of parecoxib compared with morphine for postoperative sore throat in patients undergoing laryngeal microsurgery. Fifty patients were randomly allocated to receive either parecoxib 0.5 mg/kg or morphine 50 μg/kg prior to anesthesia induction. General anesthesia was maintained with sevoflurane 2-4%. Postoperative sore throat and other outcomes were measured at a postanesthesia care unit (PACU) 4 hours and 24 hours postoperatively. The severity of postoperative sore throat was assessed by sore throat score as follows: none (0) = no pharyngeal or laryngeal discomfort; mild (1) = no pain at rest, but swallowing induced mild pain or discomfort; moderate (2) = constant pain without swallowing exacerbation; and severe (3) = constant pain with swallowing or respiratory exacerbation. The incidences of postoperative side effects (nausea, vomiting, itching, dizziness, and somnolence) were also recorded. Demographic data from the parecoxib (n = 25) and morphine (n = 25) groups did not differ significantly. The parecoxib group depicted similar sore throat scores as the morphine group at three measured postoperative time points. Patients requiring postoperative analgesics were comparable between the parecoxib group and morphine group (2/25, 8% vs. 3/25, 12%, p = 0.64). Overall postoperative adverse events were fewer in the parecoxib group than the morphine group (3/25, 12% vs. 9/25, 36%, p = 0.047). Both parecoxib and morphine are effective to attenuate postoperative sore throat after laryngeal microsurgery. Parecoxib may be an effective and well-tolerated injectable analgesic to manage postoperative sore throat after laryngeal microsurgery. Copyright © 2014. Published by Elsevier Taiwan.

  13. Combined Use of Standard and Throat Microphones for Measurement of Acoustic Voice Parameters and Voice Categorization.

    PubMed

    Uloza, Virgilijus; Padervinskis, Evaldas; Uloziene, Ingrida; Saferis, Viktoras; Verikas, Antanas

    2015-09-01

    The aim of the present study was to evaluate the reliability of the measurements of acoustic voice parameters obtained simultaneously using oral and contact (throat) microphones and to investigate utility of combined use of these microphones for voice categorization. Voice samples of sustained vowel /a/ obtained from 157 subjects (105 healthy and 52 pathological voices) were recorded in a soundproof booth simultaneously through two microphones: oral AKG Perception 220 microphone (AKG Acoustics, Vienna, Austria) and contact (throat) Triumph PC microphone (Clearer Communications, Inc, Burnaby, Canada) placed on the lamina of thyroid cartilage. Acoustic voice signal data were measured for fundamental frequency, percent of jitter and shimmer, normalized noise energy, signal-to-noise ratio, and harmonic-to-noise ratio using Dr. Speech software (Tiger Electronics, Seattle, WA). The correlations of acoustic voice parameters in vocal performance were statistically significant and strong (r = 0.71-1.0) for the entire functional measurements obtained for the two microphones. When classifying into healthy-pathological voice classes, the oral-shimmer revealed the correct classification rate (CCR) of 75.2% and the throat-jitter revealed CCR of 70.7%. However, combination of both throat and oral microphones allowed identifying a set of three voice parameters: throat-signal-to-noise ratio, oral-shimmer, and oral-normalized noise energy, which provided the CCR of 80.3%. The measurements of acoustic voice parameters using a combination of oral and throat microphones showed to be reliable in clinical settings and demonstrated high CCRs when distinguishing the healthy and pathological voice patient groups. Our study validates the suitability of the throat microphone signal for the task of automatic voice analysis for the purpose of voice screening. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  14. Evaluation of a streptococcal pharyngitis score in southern Taiwan.

    PubMed

    Shih, Ching-Tang; Lin, Ching-Chiang; Lu, Chung-Ching

    2012-02-01

    Group A streptococcus (GAS) pharyngitis can cause serious complications such as rheumatic heart disease. The McIsaac sore throat score is a clinical prediction score used to improve the detection rate of GAS pharyngitis. We evaluated the validity of the McIsaac sore throat score in Southern Taiwan and compared our findings to those of other studies. We retrospectively analyzed chart records from children aged 3 to 15 years old who complained of fever and sore throat. They had throat cultures collected at the outpatient pediatric clinic of Fooyin University Hospital, located in Pingtung County, Taiwan during the period between January 2007 and January 2010. Clinical characteristics were reviewed, and sore throat score was analyzed. A total of 342 throat cultures met the inclusion criteria of sore throat and fever. The positive rate of GAS was 4.1%. Culture-positive cases were associated with higher odds for a skin rash [adjusted odds ratio (AOR): 14.66, 95% confidence interval (CI): 4.63-46.40, p < 0.001), lower odds for cough (AOR: 0.19, 95% CI: 0.04-0.85, p = 0.030) and having a runny nose (AOR: 0.22, 95% CI: 0.05-0.99, p = 0.048). The most common physical sign was scarlet fever rash (AOR: 57.35, 95% CI: 15.45-212.98, p < 0.001). A McIsaac score of 5 had a sensitivity of 71%, specificity of 70%, and a positive predictive value of only 9.3%. Pediatric streptococcal pharyngitis in Southern Taiwan is uncommon. Diagnosis of GAS pharyngitis based on the McIsaac sore throat score is unreliable among pediatric patients with febrile pharyngitis in Southern Taiwan. Copyright © 2012. Published by Elsevier B.V.

  15. Etiologic predictive value of a rapid immunoassay for the detection of group A Streptococcus antigen from throat swabs in patients presenting with a sore throat.

    PubMed

    Orda, Ulrich; Gunnarsson, Ronny; Orda, Sabine; Fitzgerald, Mark; Rofe, Geoff; Dargan, Anna

    2016-04-01

    Clinical reasoning utilizing certain symptoms and scores has not proven to be a reliable decision-making tool to determine whether or not to suspect a group A Streptococcus (GAS) infection in the patient presenting with a sore throat. Culture as the so-called 'gold standard' is impracticable because it takes 1 to 2 days (and even longer in remote locations) for a result, and thus treatment decisions will be made without the result available. Rapid diagnostic antigen tests have demonstrated sufficient sensitivities and specificities in detecting GAS antigens to identify GAS throat infections. Throat swab samples were collected from patients attending the Mount Isa Hospital emergency department for a sore throat; these samples were compared to swab samples collected from healthy controls who did not have a sore throat. Both groups were aged 3-15 years. All swab samples were analyzed with a point-of-care test (Alere Test Pack +Plus with OBC Strep A). The etiologic predictive value (EPV) of the throat swab was calculated. The 95% confidence interval for positive EPV was 88-100% and for negative EPV was 97-99%, depending on assumptions made. This study demonstrates that the point-of-care test Alere Test Pack +Plus Strep A has a high positive predictive value and is able to rule in GAS infection as long as the proportion of carriers is low. Also the negative predictive value for ruling out GAS as the etiologic agent is very high irrespective of the carrier rate. Hence, this test is always useful to rule out GAS infection. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. An intelligent artificial throat with sound-sensing ability based on laser induced graphene

    PubMed Central

    Tao, Lu-Qi; Tian, He; Liu, Ying; Ju, Zhen-Yi; Pang, Yu; Chen, Yuan-Quan; Wang, Dan-Yang; Tian, Xiang-Guang; Yan, Jun-Chao; Deng, Ning-Qin; Yang, Yi; Ren, Tian-Ling

    2017-01-01

    Traditional sound sources and sound detectors are usually independent and discrete in the human hearing range. To minimize the device size and integrate it with wearable electronics, there is an urgent requirement of realizing the functional integration of generating and detecting sound in a single device. Here we show an intelligent laser-induced graphene artificial throat, which can not only generate sound but also detect sound in a single device. More importantly, the intelligent artificial throat will significantly assist for the disabled, because the simple throat vibrations such as hum, cough and scream with different intensity or frequency from a mute person can be detected and converted into controllable sounds. Furthermore, the laser-induced graphene artificial throat has the advantage of one-step fabrication, high efficiency, excellent flexibility and low cost, and it will open practical applications in voice control, wearable electronics and many other areas. PMID:28232739

  17. An intelligent artificial throat with sound-sensing ability based on laser induced graphene.

    PubMed

    Tao, Lu-Qi; Tian, He; Liu, Ying; Ju, Zhen-Yi; Pang, Yu; Chen, Yuan-Quan; Wang, Dan-Yang; Tian, Xiang-Guang; Yan, Jun-Chao; Deng, Ning-Qin; Yang, Yi; Ren, Tian-Ling

    2017-02-24

    Traditional sound sources and sound detectors are usually independent and discrete in the human hearing range. To minimize the device size and integrate it with wearable electronics, there is an urgent requirement of realizing the functional integration of generating and detecting sound in a single device. Here we show an intelligent laser-induced graphene artificial throat, which can not only generate sound but also detect sound in a single device. More importantly, the intelligent artificial throat will significantly assist for the disabled, because the simple throat vibrations such as hum, cough and scream with different intensity or frequency from a mute person can be detected and converted into controllable sounds. Furthermore, the laser-induced graphene artificial throat has the advantage of one-step fabrication, high efficiency, excellent flexibility and low cost, and it will open practical applications in voice control, wearable electronics and many other areas.

  18. Genetic Diversity among Group A Streptococcus Isolated from Throats of Healthy and Symptomatic Children

    PubMed Central

    Kashyap, Nitin; Kanga, Anil; Thakur, Kamlesh; Sood, Anuradha; Chandel, Lata

    2016-01-01

    Background: Group A streptococcus (GAS) is the commonest bacterial cause of pharyngitis. Children in the age group of 5–15 years are most commonly affected. It can also colonize throats of healthy children in this age group. Both cases and carriers can transmit it in the community. Methods: Throat swab samples were collected from 1849 asymptomatic and 371 symptomatic children. Results: The rate of isolation of GAS was 1.41% among the asymptomatic group and 7.55% among the symptomatic group. Nine different emm types were encountered in the asymptomatic children and 14 among the symptomatic children. Conclusion: Throat swab cultures must be used in all cases of pharyngitis. Early and appropriate antibiotic therapy will prevent complications. Asymptomatic throat carriage of GAS in children was low in our study. However, they can still act as reservoirs. Emm typing helps in understanding epidemiology and finding new types. PMID:26743337

  19. Response to nestling throat ligatures by three songbirds

    USGS Publications Warehouse

    Robinson, G.L.; Conway, C.J.; Kirkpatrick, C.; Laroche, D.D.

    2010-01-01

    We attempted to collect diet samples using throat ligatures from nestlings of three songbird species in a riparian woodland in southeastern Arizona from May to August 2009. We had success with Song Sparrows (Melospiza melodia), observed adult Yellow-breasted Chats (Icteria virens) reclaim food from nestlings, and discontinued the use of throat ligatures when we observed an adult Abert's Towhee (Pipilo aberti) remove two, 34-day-old ligatured nestlings from its nest. Previous studies have reported problems (e.g., aggression toward nestlings by adults) with throat ligatures, but we are the first to document removal (and subsequent nestling mortality) in response to this technique. We urge investigators to exercise caution when using throat ligatures on species for which evidence of the safety and efficacy of this method are lacking, especially when nestlings are small in size relative to adults. ?? 2010 by the Wilson Ornithological Society.

  20. An intelligent artificial throat with sound-sensing ability based on laser induced graphene

    NASA Astrophysics Data System (ADS)

    Tao, Lu-Qi; Tian, He; Liu, Ying; Ju, Zhen-Yi; Pang, Yu; Chen, Yuan-Quan; Wang, Dan-Yang; Tian, Xiang-Guang; Yan, Jun-Chao; Deng, Ning-Qin; Yang, Yi; Ren, Tian-Ling

    2017-02-01

    Traditional sound sources and sound detectors are usually independent and discrete in the human hearing range. To minimize the device size and integrate it with wearable electronics, there is an urgent requirement of realizing the functional integration of generating and detecting sound in a single device. Here we show an intelligent laser-induced graphene artificial throat, which can not only generate sound but also detect sound in a single device. More importantly, the intelligent artificial throat will significantly assist for the disabled, because the simple throat vibrations such as hum, cough and scream with different intensity or frequency from a mute person can be detected and converted into controllable sounds. Furthermore, the laser-induced graphene artificial throat has the advantage of one-step fabrication, high efficiency, excellent flexibility and low cost, and it will open practical applications in voice control, wearable electronics and many other areas.

  1. Shock position sensor for supersonic inlets. [measuring pressure in the throat of a supersonic inlet

    NASA Technical Reports Server (NTRS)

    Dustin, M. O. (Inventor)

    1975-01-01

    Static pressure taps or ports are provided in the throat of a supersonic inlet, and signals indicative of the pressure at each of the ports is fed to respective comparators. Means are also provided for directing a signal indicative of the total throat pressure to the comparators. A periodic signal is superimposed on the total throat pressure so that the signal from the static pressure tabs is compared to a varying scan signal rather than to total throat pressure only. This type of comparison causes each comparator to provide a pulse width modulated output which may vary from 0% 'time on' to 100% 'time on'. The pulse width modulated outputs of the comparators are summed, filtered, and directed to a controller which operates a bypass valve such as a door whereby air is dumped from the inlet to prevent the shock wave from being expelled out the front.

  2. Epizootiology of arenaviral infections in the white-throated woodrat (Muridae: Sigmodontinae) and other woodrats in Arizona.

    PubMed

    Abbott, Ken D; Milazzo, Mary L; Keith, Josh; Bradley, Robert D; Fulhorst, Charles F

    2004-12-01

    The purpose of this study was to extend and refine our knowledge of the geographical distribution and natural host relationships of the arenaviruses associated with woodrats indigenous to Arizona. Antibody to a Tacaribe serocomplex virus was found in 112 of 1,250 white-throated woodrats, five of 208 Mexican woodrats, one of 114 Stephen's woodrats, and none of 862 other rodents captured at 51 sites in 10 counties in Arizona. Of the 112 antibody-positive white-throated woodrats, 109 (97.3%) were captured within extensive, dense patches of prickly pear cactus and cane cholla in three counties in mid-central Arizona. Analysis of the serological and zoographical data suggested that white-throated woodrats usually become infected early in life and that the distribution of antibody-positive white-throated woodrats in Arizona is not linked to a specific biome.

  3. Qualities of Sore Throat Index (QuaSTI): measuring descriptors of sore throat in a randomized, placebo-controlled trial.

    PubMed

    Schachtel, Bernard; Shephard, Adrian; Schachtel, Emily; Lorton, Mary Beth; Shea, Tim; Aspley, Sue

    2018-03-01

    Patients with pharyngitis often describe various sensory, affective and evaluative pain qualities. Using an 11-word/phrase index, the Qualities of Sore Throat Index (QuaSTI), we characterized throat symptoms and evaluated changes in a randomized controlled trial (NCT01986361). Patients received a single flurbiprofen 8.75 mg (n = 101) or placebo (n = 21) lozenge and rated throat soreness at baseline and regular intervals over 3 h, and the QuaSTI at baseline, 1, 2 and 3 h post-treatment. The QuaSTI distinguished active drug from placebo and detected clinically important (≥2-point) changes over 3 h. Mean change from baseline over 3 h was significantly greater for flurbiprofen (154%) than placebo (p < 0.05). The QuaSTI is a sensitive instrument for measuring therapeutic effects in patients with pharyngitis.

  4. Extreme throat initial data set and horizon area-angular momentum inequality for axisymmetric black holes

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

    Dain, Sergio; Max Planck Institute for Gravitational Physics

    2010-11-15

    We present a formula that relates the variations of the area of extreme throat initial data with the variation of an appropriate defined mass functional. From this expression we deduce that the first variation, with fixed angular momentum, of the area is zero and the second variation is positive definite evaluated at the extreme Kerr throat initial data. This indicates that the area of the extreme Kerr throat initial data is a minimum among this class of data. And hence the area of generic throat initial data is bounded from below by the angular momentum. Also, this result strongly suggestsmore » that the inequality between area and angular momentum holds for generic asymptotically flat axially symmetric black holes. As an application, we prove this inequality in the nontrivial family of spinning Bowen-York initial data.« less

  5. MX Siting Investigation. DTN/OBTS Field Surveys. Volume III. Biological Resources Nevada and Utah.

    DTIC Science & Technology

    1981-11-30

    Black - throated sparrow (Amphispiza bilineata) X X X REPTILES Desert tortoise (Gopherus agassizi) X X Zebra-tailed...observed on the greatest number of sites was the black - throated sparrow (Amphispiza bilineata). The reptile most frequently observed was the side-blotched...Poliopt~ila caerula Loggerhead shrike Lanius ludovicianus Black - throated sparrow Amphispiza bilineata Unidentified sparrow Unidentified buteo REPTILES

  6. 21 CFR 874.4350 - Ear, nose, and throat fiberoptic light source and carrier.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat fiberoptic light source and carrier. 874.4350 Section 874.4350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... of plastic fibers and that is intended to provide illumination at the tip of an ear, nose, or throat...

  7. Physical Standards for Appointment , Enlistment, and Induction

    DTIC Science & Technology

    1994-05-02

    Pharynx , Trachea, and Larynx 1-24 Y. Other Defects and Diseases of the Mouth, Nose , Throat , Pharynx , and...or conditions of the mouth, tongue, throat , pharynx , larynx , and nose that interfere with mastication and swallowing of ordinary food, or with speech...Tracheostomy or tracheal fistula. y. OTHER DEFECTS AND DISEASES OF THEMOUTH. NOSE . THROAT . PARYNXAND LARYNX The causes for rejection for

  8. Metal atomization spray nozzle

    DOEpatents

    Huxford, Theodore J.

    1993-01-01

    A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal.

  9. Throat-bypass bleed systems for increasing the stable airflow range of a Mach 2.50 axisymmetric inlet with 40-percent internal contraction

    NASA Technical Reports Server (NTRS)

    Sanders, B. W.; Mitchell, G. A.

    1973-01-01

    The results of an experimental investigation to increase the stable airflow range of a super sonic mixed-compression inlet are presented. Various throat-bypass bleeds were located on the inlet cowl. The bleed types were distributed porous normal holes, a forward slanted slot, or distributed educated slots. Large inlet stability margins were obtained with the inlet throat bleed systems if a constant pressure was maintained in the throat-bypass bleed plenum. Stability limits were determined for steady-state and limited transient internal air flow changes. Limited unstart angle-of-attack data are presented.

  10. Incidence angle bounds for lip flow separation of three 13.97-centimeter-diameter inlets

    NASA Technical Reports Server (NTRS)

    Luidens, R. W.; Abbott, J. M.

    1976-01-01

    Low speed wind tunnel tests were conducted to establish a procedure for determining inlet-lip flow separation and to make preliminary examination of the incidence angle bounds for lip flow separation on inlets intended for the nacelles of STOL (short takeoff and landing) aircraft. Three inlets were tested. Two of the inlets had short centerbodies with lower lip area contraction ratios of 1.30 and 1.44. The third inlet had a cylindrical centerbody extended forward into the inlet throat with a lower lip area contraction ratio of 1.44. The inlets were sized to fit a 13.97 centimeter-diameter fan. For inlet throat Mach numbers less than about 0.43, the lip flow separation angle was increased by either increasing the ratio of throat velocity to freestream velocity (Vt/Vo) or by increasing the lower lip area contraction ratio. For throat Mach numbers greater than a certain value (ranging from 0.43 to 0.52), increasing throat Mach number in some cases resulted in a decrease in the lip flow separation angle. Extending a cylindrical centerbody into the inlet throat increased the flow separation angle for nearly all values of Vt/Vo.

  11. Does cuff pressure monitoring reduce postoperative pharyngolaryngeal adverse events after LMA-ProSeal insertion? A parallel group randomised trial.

    PubMed

    Vasanth Karthik, R; Ranganathan, Priya; Kulkarni, Atul P; Sharma, Kailash S

    2014-10-01

    The incidence of postoperative pharyngolaryngeal complications after laryngeal mask airway (LMA) insertion can be as high as 50%. Over-inflation of the LMA cuff may be a causal factor. We conducted a single-centre parallel group randomised trial to determine whether maintaining LMA-ProSeal intra-cuff pressures below 60 cm H2O decreases postoperative pharyngolaryngeal complications. We recruited 120 adult patients who were scheduled to undergo elective surgery under general anaesthesia. Appropriate sized LMA-ProSeal was inserted and the cuff was inflated with air (to no more than the maximum recommended volume) until there was no audible leak. Patients were randomised to either the control group (n = 60), where the intra-cuff pressure was noted and no further action was taken, or to the pressure-monitored group (n = 60), where intra-cuff pressure was maintained below 60 cm H2O. Pharyngolaryngeal complications consisting of sore throat, dysphonia and dysphagia were assessed at 1, 2, and 24 h postoperatively. Patients, anaesthesiologists and assessors were blinded to group allocation. The primary outcome was a composite endpoint of any pharyngolaryngeal complication at any of the three time points. Secondary outcomes were the incidence of individual outcomes at each time point. The incidence of pharyngolaryngeal complications at any time point was 42% in the routine care group and 32% in the pressure-monitored group (95% CI for difference +28 to -7%, p = 0.26). There was no difference between groups for any of the secondary outcomes. Our study failed to demonstrate a statistically significant reduction in postoperative pharyngolaryngeal complications by limiting intra-cuff pressures in the LMA-Proseal.

  12. Activating "Invisible" Glue: Using Electron Beam for Enhancement of Interfacial Properties of Graphene-Metal Contact.

    PubMed

    Kim, Songkil; Russell, Michael; Kulkarni, Dhaval D; Henry, Mathias; Kim, Steve; Naik, Rajesh R; Voevodin, Andrey A; Jang, Seung Soon; Tsukruk, Vladimir V; Fedorov, Andrei G

    2016-01-26

    Interfacial contact of two-dimensional graphene with three-dimensional metal electrodes is crucial to engineering high-performance graphene-based nanodevices with superior performance. Here, we report on the development of a rapid "nanowelding" method for enhancing properties of interface to graphene buried under metal electrodes using a focused electron beam induced deposition (FEBID). High energy electron irradiation activates two-dimensional graphene structure by generation of structural defects at the interface to metal contacts with subsequent strong bonding via FEBID of an atomically thin graphitic interlayer formed by low energy secondary electron-assisted dissociation of entrapped hydrocarbon contaminants. Comprehensive investigation is conducted to demonstrate formation of the FEBID graphitic interlayer and its impact on contact properties of graphene devices achieved via strong electromechanical coupling at graphene-metal interfaces. Reduction of the device electrical resistance by ∼50% at a Dirac point and by ∼30% at the gate voltage far from the Dirac point is obtained with concurrent improvement in thermomechanical reliability of the contact interface. Importantly, the process is rapid and has an excellent insertion potential into a conventional fabrication workflow of graphene-based nanodevices through single-step postprocessing modification of interfacial properties at the buried heterogeneous contact.

  13. Measurements of tungsten migration in the DIII-D divertor

    NASA Astrophysics Data System (ADS)

    Wampler, W. R.; Rudakov, D. L.; Watkins, J. G.; McLean, A. G.; Unterberg, E. A.; Stangeby, P. C.

    2017-12-01

    An experimental study of migration of tungsten in the DIII-D divertor is described, in which the outer strike point of L-mode plasmas was positioned on a toroidal ring of tungsten-coated metal inserts. Net deposition of tungsten on the divertor just outside the strike point was measured on graphite samples exposed to various plasma durations using the divertor materials evaluation system. Tungsten coverage, measured by Rutherford backscattering spectroscopy (RBS), was found to be low and nearly independent of both radius and exposure time closer to the strike point, whereas farther from the strike point the W coverage was much larger and increased with exposure time. Depth profiles from RBS show this was due to accumulation of thicker mixed-material deposits farther from the strike point where the plasma temperature is lower. These results are consistent with a low near-surface steady-state coverage on graphite undergoing net erosion, and continuing accumulation in regions of net deposition. This experiment provides data needed to validate, and further improve computational simulations of erosion and deposition of material on plasma-facing components and transport of impurities in magnetic fusion devices. Such simulations are underway and will be reported later.

  14. Dexpanthenol pastille and benzydamine hydrochloride spray for the prevention of post-operative sore throat.

    PubMed

    Gulhas, N; Canpolat, H; Cicek, M; Yologlu, S; Togal, T; Durmus, M; Ozcan Ersoy, M

    2007-02-01

    In this study, we aimed to compare the effectiveness of dexpanthenol pastille and benzydamine hydrochloride spray on the prevention of a sore throat. One hundred and eighty patients undergoing general anaesthesia, who were ASA I-II and with their ages ranging between 15 and 70 years, were randomly allocated to three groups, each consisting of 60 patients. For group B, four puffs of benzydamine hydrochloride were sprayed into the mouth initially 30 min before the operation and repeatedly 5 min before anaesthesia induction. For group D, two pastilles of dexpanthenol were administered orally to be sucked 30 min before the operation. For group P, four puffs of distilled water were sprayed into the mouth initially 30 min before the operation. Post-operatively, patients were evaluated for a sore throat for the duration of 24 h. The incidence of a sore throat was significantly lower for group D when compared with group B and group P. The incidence of a sore throat was similar for group B and group P. According to the sore throat grading system, the number of patients experiencing no complaints was significantly higher for group D when compared with group B and group P. The number of patients achieving moderate scores was significantly higher for group B when compared with group D. The administration of 200 mg of dexpanthenol prophylactically before endotracheal intubation is effective in the prevention of post-operative sore throat.

  15. Speech intelligibility in noise using throat and acoustic microphones.

    PubMed

    Acker-Mills, Barbara E; Houtsma, Adrianus J M; Ahroon, William A

    2006-01-01

    Helicopter cockpits are very noisy and this noise must be reduced for effective communication. The standard U.S. Army aviation helmet is equipped with a noise-canceling acoustic microphone, but some ambient noise still is transmitted. Throat microphones are not sensitive to air molecule vibrations and thus, transmittal of ambient noise is reduced. It is possible that throat microphones could enhance speech communication in helicopters, but speech intelligibility with the devices must first be assessed. In the current study, speech intelligibility of signals generated by an acoustic microphone, a throat microphone, and by the combined output of the two microphones was assessed using the Modified Rhyme Test (MRT). Stimulus words were recorded in a reverberant chamber with ambient broadband noise intensity at 90 and 106 dBA. Listeners completed the MRT task in the same settings, thus simulating the typical environment of a rotary-wing aircraft. Results show that speech intelligibility is significantly worse for the throat microphone (average percent correct = 55.97) than for the acoustic microphone (average percent correct = 69.70), particularly for the higher noise level. In addition, no benefit is gained by simultaneously using both microphones. A follow-up experiment evaluated different consonants using the Diagnostic Rhyme Test and replicated the MRT results. The current results show that intelligibility using throat microphones is poorer than with the use of boom microphones in noisy and in quiet environments. Therefore, throat microphones are not recommended for use in any situation where fast and accurate speech intelligibility is essential.

  16. Advanced Monitoring of Migratory Birds on Military Lands

    DTIC Science & Technology

    2010-03-01

    BRSP Brewer‟s Sparrow BTSP Black - throated Sparrow BLGR Blue Grosbeak CAKI Cassin‟s Kingbird CONI Common Nighthawk EAME Eastern...Fuller et al. 1998). This approach has been used for many species, ranging from Black - throated Sparrow (Amphispiza bilineata, Pidgeon et al 2003) to...lightest yellow indicates a predicted abundance of zero. Species acronym key: BTSP Black - throated Sparrow ; EAME Eastern Meadowlark; WEKI Western

  17. Metal atomization spray nozzle

    DOEpatents

    Huxford, T.J.

    1993-11-16

    A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

  18. Electrochemical and thermodynamic studies of the electrode materials for lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Bang, Hyun Joo

    A series of graphite samples were tested for their electrochemical performance as anode material for lithium ion cells. Specially treated natural graphite samples showed good reversible capacities and relatively small irreversible capacity losses. The good performance of these samples can be explained by the low surface area associated with the rounded edges and absence of exfoliation due to the presence of the rhombohedral phase and defects in the grain boundaries. Graphitized cokes showed larger irreversible capacity losses while mesophase carbons showed lower reversible capacity. The treated natural graphite samples, especially LBG25 were found to be high performance, low cost anode materials for the lithium ion cells. The electrochemical and thermal behaviors of the spinels---LiMn 2O4, LiCo1/6Mn11/6O4, LiFe 1/6Mn11/6O4, and LiNi1/6Mn11/6 O4 were studied using electrochemical and thermochemical techniques. The electrochemical techniques included cyclic voltammetry, charge/discharge cycling of 2016 coin cells and diffusion coefficient measurements using Galvanostatic Intermittent Titration Technique. Better capacity retention(GITT) was observed for the substituted spinels (0.11% loss/cycle for LiCo1/6Mn 11/6O4; 0.3% loss/cycle for LiFe1/6Mn11/6 O4; and 0.2% loss/cycle for LiNi1/6Mn11/6 O4) than for the lithium manganese dioxide spinel (1.6% loss/cycle for first 10 cycles, 0.9% loss/cycle for 33 cycles) during 33 cycles. The Differential Scanning Calorimetry (DSC) results showed that the cobalt substituted spinel has better thermal stability than the lithium manganese oxide and other substituted spinels. The thermal profile of LiMn2O4 and LiAl0.17 Mn1.83O3.97S0.03 was measured in an isothermal micro-calorimeter. The heat contributions are discussed in terms of reversible and irreversible heat generation, in combination with the entropy change directly obtained by the dE/dT measurements and the over-potential measurements. The endothermic and exothermic heat profiles observed during the charge and discharge processes are related to the Li insertion/extraction reaction in the spinel host structure for both materials. The reversible heat generation due to the lithium insertion/extraction reaction in the host electrode is estimated on the basis of the cell entropy change. The heat generation calculated from DeltaS and the open circuit potential results is consistent with the heat profile (exothermic/endothermic) generated during the charge/discharge process and with the magnitude of the heat generation from the experimental results obtained from the IMC at a slow charge/discharge rate. The irreversible heat generation dependence on the current rate is discussed at different discharge rates.

  19. Apparatus for establishing flow of a fluid mass having a known velocity

    NASA Technical Reports Server (NTRS)

    Price, P.; Veikins, O.; Bate, E. R., Jr.; Jones, R. H. (Inventor)

    1974-01-01

    An apparatus for establishing a flow of fluid mass, such as gas, having a known velocity is introduced. The apparatus is characterized by an hermetically sealed chamber conforming to a closed-loop configuration and including a throat and a plurality of axially displaceable pistons for sweeping through the throat a stream of gas including a core and an unsheared boundary layer. Within the throat there is a cylindrical coring body concentrically related to the throat for receiving the core, and a chamber surrounding the cylindrical body for drawing off the boundary layer, whereby the velocity of the core is liberated from the effects of the velocity of the boundary layer.

  20. [Development of throat clearing herbal teas].

    PubMed

    Puodziūniene, Gene; Janulis, Valdimaras; Milasius, Arvydas; Budnikas, Milasius

    2004-01-01

    Medicinal herbs in tea for throat clearing are used from ancient times. Taking into consideration the bronchial mucus secretion stimulating and antispasmodic, antimicrobial, antiphlogistic and stimulating effect on the ciliated epithelium two new formulations of throat clearing herbal tea were originated. The first formulation consists of liquorice roots, sweet fennel and thyme, and the second one consists of pine gemmae, thyme and elder flowers. The methods for identification and assay of the active substances of the components were adapted. The purity of the mixtures was regulated by the limitation of the loss on drying, total ash, microbial contamination, contamination with radionuclides, heavy metals, pesticides and foreign matter. Expiry date of both throat clearing herbal teas was confirmed to be 2 years.

  1. MEANS FOR COOLING REACTORS

    DOEpatents

    Wheeler, J.A.

    1957-11-01

    A design of a reactor is presented in which the fuel elements may be immersed in a liquid coolant when desired without the necessity of removing them from the reactor structure. The fuel elements, containing the fissionable material are in plate form and are disposed within spaced slots in a moderator material, such as graphite to form the core. Adjacent the core is a tank containing the liquid coolant. The fuel elements are mounted in spaced relationship on a rotatable shaft which is located between the core and the tank so that by rotation of the shaft the fuel elements may be either inserted in the slots in the core to sustain a chain reaction or immersed in the coolant.

  2. Analytical study of striated nozzle flow with small radius of curvature ratio throats

    NASA Technical Reports Server (NTRS)

    Norton, D. J.; White, R. E.

    1972-01-01

    An analytical method was developed which is capable of estimating the chamber and throat conditions in a nozzle with a low radius of curvature throat. The method was programmed using standard FORTRAN 4 language and includes chemical equilibrium calculation subprograms (modified NASA Lewis program CEC71) as an integral part. The method determines detailed and gross rocket characteristics in the presence of striated flows and gives detailed results for the motor chamber and throat plane with as many as 20 discrete zones. The method employs a simultaneous solution of the mass, momentum, and energy equations and allows propellant types, 0/F ratios, propellant distribution, nozzle geometry, and injection schemes to be varied so to predict spatial velocity, density, pressure, and other thermodynamic variable distributions in the chamber as well as the throat. Results for small radius of curvature have shown good comparison to experimental results. Both gaseous and liquid injection may be considered with frozen or equilibrium flow calculations.

  3. Genetic Diversity among Group A Streptococcus Isolated from Throats of Healthy and Symptomatic Children.

    PubMed

    Chauhan, Smriti; Kashyap, Nitin; Kanga, Anil; Thakur, Kamlesh; Sood, Anuradha; Chandel, Lata

    2016-04-01

    Group A streptococcus (GAS) is the commonest bacterial cause of pharyngitis. Children in the age group of 5-15 years are most commonly affected. It can also colonize throats of healthy children in this age group. Both cases and carriers can transmit it in the community. Throat swab samples were collected from 1849 asymptomatic and 371 symptomatic children. The rate of isolation of GAS was 1.41% among the asymptomatic group and 7.55% among the symptomatic group. Nine different emm types were encountered in the asymptomatic children and 14 among the symptomatic children. Throat swab cultures must be used in all cases of pharyngitis. Early and appropriate antibiotic therapy will prevent complications. Asymptomatic throat carriage of GAS in children was low in our study. However, they can still act as reservoirs. Emm typing helps in understanding epidemiology and finding new types. © The Author [2016]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Normal Gravity Testing of a Microchannel Phase Separator for In Situ Resource Utilization

    NASA Technical Reports Server (NTRS)

    TeGrotenhuis, Ward E.; Stenkamp, Victoria S.; McQuillen, John (Technical Monitor)

    2001-01-01

    A microchannel separator, with 2.7 millimeters as the smallest dimension, was tested, and a pore throat structure captured and removed liquid from a gas-liquid stream. The microchannel device was tested over a of gas and liquid flow rates ranging from 0.0005 up to 0. 14 volume fraction of liquid. Four liquids were tested with air. The biggest factor affecting the throughput is the capacity of liquid flow through the pore throat, which is dictated by permeability, liquid viscosity, flow area, pore throat thickness, and pressure difference across the pore throat. Typically, complete separation of gas and liquid fractions was lost when the liquid flow rate reached about 40 to 60% of the pore throat capacity. However, this could occur over a range of 10 to 90% utilization of pore throat capacity. Breakthrough occurs in the microchannel phase separator at conditions similar to the annular to plug flow transition of two-phase microgravity pipe flow implying that operating in the proper flow regime is crucial. Analysis indicates that the Bond number did not affect performance, supporting the premise that hydrodynamic, interfacial, and capillary forces are more important than gravity. However, the relative importance of gravity is better discerned through testing under reduced gravity conditions.

  5. Heat transfer to throat tubes in a square-chambered rocket engine at the NASA Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Nesbitt, James A.; Brindley, William J.

    1989-01-01

    A gaseous H2/O2 rocket engine was constructed at the NASA-Lewis to provide a high heat flux source representative of the heat flux to the blades in the high pressure fuel turbopump (HPFTP) during startup of the space shuttle main engines. The high heat flux source was required to evaluate the durability of thermal barrier coatings being investigated for use on these blades. The heat transfer, and specifically, the heat flux to tubes located at the throat of the test rocket engine was evaluated and compared to the heat flux to the blades in the HPFTP during engine startup. Gas temperatures, pressures and heat transfer coefficients in the test rocket engine were measured. Near surface metal temperatures below thin thermal barrier coatings were also measured at various angular orientations around the throat tube to indicate the angular dependence of the heat transfer coefficients. A finite difference model for a throat tube was developed and a thermal analysis was performed using the measured gas temperatures and the derived heat transfer coefficients to predict metal temperatures in the tube. Near surface metal temperatures of an uncoated throat tube were measured at the stagnation point and showed good agreement with temperatures predicted by the thermal model. The maximum heat flux to the throat tube was calculated and compared to that predicted for the leading edge of an HPFTP blade. It is shown that the heat flux to an uncooled throat tube is slightly greater than the heat flux to an HPFTP blade during engine startup.

  6. Community-acquired methicillin-resistant Staphylococcus aureus can persist in the throat.

    PubMed

    Hamdan-Partida, Aida; González-García, Samuel; de la Rosa García, Estela; Bustos-Martínez, Jaime

    2018-06-01

    Colonization by Staphylococcus aureus is an important factor in infections caused by this microorganism. Among the colonization niches of staphylococci are the nose, skin, intestinal tract, and, recently, the throat has been given relevance. Infections caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) can be fatal. Persistence of S. aureus is an important process in the pathogenesis of this microorganism and must be studied. The aim of this study was to determine the persistence of S. aureus in the throat, and characterized the strains. We studied the persistence of S. aureus for 6 years in the throat of apparently healthy people. The isolated strains from the persistent carriers were characterized through PFGE, spa-typing, SCCmec typing, resistance to methicillin, presence of virulence genes (adhesins and toxins), and the formation of biofilm. We found persistent and intermittent carriers of S. aureus in the throat, with methicillin-sensitive (MSSA), methicillin-resistant (MRSA) strains, and confirmed for the first time that CA-MRSA colonizes this niche. These strains can colonize persistently the throat for four years or more. Typification of strains through PFGE and spa-typing revealed that some carriers present the same strain, whereas others present different strains along the period of persistence. Almost all strains induced a strong biofilm formation. All strains presented adhesin and toxin genes, but no shared genotype was found. We conclude that S. aureus, including CA-MRSA strains, can remain persistently in the throat, finding a wide variability among the persistent strains. Copyright © 2018 Elsevier GmbH. All rights reserved.

  7. A comparative study of the diagnostic methods for Group A streptococcal sore throat in two reference hospitals in Yaounde, Cameroon

    PubMed Central

    Gonsu, Hortense Kamga; Bomki, Cynthia Mbimenyuy; Djomou, François; Toukam, Michel; Ndze, Valantine Ngum; Lyonga, Emilia Enjema; Mbakop, Calixte Didier; Koulla-Shiro, Sinata

    2015-01-01

    Introduction Sore throat is a common complaint in general practice which is more frequent in children. The most frequent pathogenic bacteria associated with this infection is Streptococcus pyogenes. Rapid Antigen Diagnostic Test (RADT) facilitates the rapid identification and consequently prompt treatment of patients, prevents complications, and also reduces the risk of spread of Group A Streptococcus (GAS). The main objective of this study was to assess the diagnostic value of a rapid streptococcal antigen detection test in patients with sore throat. Methods A cross-sectional descriptive study was carried out from January to April 2011 on patients aged 3 to 72 years consulting for pharyngitis or sore throat at the paediatric and Ear, Nose and Throat units of the University Teaching Hospital Yaounde and the Central Hospital Yaounde. Two throat swabs were collected per patient. One was used for the rapid test and the other for standard bacteriological analysis. Results The prevalence of GAS in the study population was 22.5%. Out of the 71 samples collected, the RADT detected group A streptococcal antigens in 12 of 16 positive cultures giving a sensitivity of 75%. The specificity of the rapid test was 96%, with positive predictive value of 85.7%, and negative predictive value of 93% respectively. Conclusion Rapid test may have an additional value in the management of patients with high risk of having GAS infection. However, tests with a higher sensitivity are needed for accurate and reliable results for early diagnosis of patients with sore throat caused by GAS. PMID:27386017

  8. A comparative study of the diagnostic methods for Group A streptococcal sore throat in two reference hospitals in Yaounde, Cameroon.

    PubMed

    Gonsu, Hortense Kamga; Bomki, Cynthia Mbimenyuy; Djomou, François; Toukam, Michel; Ndze, Valantine Ngum; Lyonga, Emilia Enjema; Mbakop, Calixte Didier; Koulla-Shiro, Sinata

    2015-01-01

    Sore throat is a common complaint in general practice which is more frequent in children. The most frequent pathogenic bacteria associated with this infection is Streptococcus pyogenes. Rapid Antigen Diagnostic Test (RADT) facilitates the rapid identification and consequently prompt treatment of patients, prevents complications, and also reduces the risk of spread of Group A Streptococcus (GAS). The main objective of this study was to assess the diagnostic value of a rapid streptococcal antigen detection test in patients with sore throat. A cross-sectional descriptive study was carried out from January to April 2011 on patients aged 3 to 72 years consulting for pharyngitis or sore throat at the paediatric and Ear, Nose and Throat units of the University Teaching Hospital Yaounde and the Central Hospital Yaounde. Two throat swabs were collected per patient. One was used for the rapid test and the other for standard bacteriological analysis. The prevalence of GAS in the study population was 22.5%. Out of the 71 samples collected, the RADT detected group A streptococcal antigens in 12 of 16 positive cultures giving a sensitivity of 75%. The specificity of the rapid test was 96%, with positive predictive value of 85.7%, and negative predictive value of 93% respectively. Rapid test may have an additional value in the management of patients with high risk of having GAS infection. However, tests with a higher sensitivity are needed for accurate and reliable results for early diagnosis of patients with sore throat caused by GAS.

  9. Protocol for north of England and Scotland study of tonsillectomy and adeno-tonsillectomy in children (NESSTAC). A pragmatic randomised controlled trial comparing surgical intervention with conventional medical treatment in children with recurrent sore throats

    PubMed Central

    Bond, John; Wilson, Janet; Eccles, Martin; Vanoli, Alessandra; Steen, Nick; Clarke, Ray; Zarod, Andrew; Lock, Catherine; Brittain, Katie; Speed, Chris; Rousseau, Nikki

    2006-01-01

    Background Uncertainties surrounding the effectiveness and cost-effectiveness of childhood tonsillectomy for recurrent sore throat led the NHS Health Technology Assessment Programme to commission this research to evaluate the effectiveness and cost-effectiveness of tonsillectomy and adeno-tonsillectomy in comparison with standard non-surgical management in children aged under 16 with recurrent throat infections. The aim is to evaluate if tonsillectomy and adeno-tonsillectomy reduces the number of episodes of sore throats among children to a clinically significant extent. Methods/design A simple prospective pragmatic randomised controlled trial with economic analysis and prospective cohort study of non-trial participants comparing surgical intervention with conventional medical treatment. The treatment arm will receive tonsillectomy and adeno-tonsillectomy while in the control arm non-surgical conventional medical treatment only will be used. The primary outcome measure will be reported number of episodes of sore throat over two years with secondary outcomes measures of reported number of episodes of sore throat, otitis media and upper respiratory tract infection which invoke a GP consultation; reported number of symptom-free days; reported severity of sore throats and surgical and anaesthetic morbidity. The study will take place in five hospitals in the UK. The trial population will be 406 children aged 4–15 on their last birthday with recurrent sore throat referred by primary care to the 5 otolaryngology departments. The duration of the study is seven years (July 2001- July 2008). Discussion As with all pragmatic randomised controlled trials it is impossible to control the external environment in which the research is taking place. Since this trial began a number of factors have arisen which could affect the outcome including; a reduction in the incidence of respiratory tract infections, marked socio-economic differences in consultation rates, the results from the National Prospective Tonsillectomy Audit and the Government's waiting list initiatives. PMID:16899123

  10. Protocol for north of England and Scotland study of tonsillectomy and adeno-tonsillectomy in children (NESSTAC). A pragmatic randomised controlled trial comparing surgical intervention with conventional medical treatment in children with recurrent sore throats.

    PubMed

    Bond, John; Wilson, Janet; Eccles, Martin; Vanoli, Alessandra; Steen, Nick; Clarke, Ray; Zarod, Andrew; Lock, Catherine; Brittain, Katie; Speed, Chris; Rousseau, Nikki

    2006-08-09

    Uncertainties surrounding the effectiveness and cost-effectiveness of childhood tonsillectomy for recurrent sore throat led the NHS Health Technology Assessment Programme to commission this research to evaluate the effectiveness and cost-effectiveness of tonsillectomy and adeno-tonsillectomy in comparison with standard non-surgical management in children aged under 16 with recurrent throat infections. The aim is to evaluate if tonsillectomy and adeno-tonsillectomy reduces the number of episodes of sore throats among children to a clinically significant extent. A simple prospective pragmatic randomised controlled trial with economic analysis and prospective cohort study of non-trial participants comparing surgical intervention with conventional medical treatment. The treatment arm will receive tonsillectomy and adeno-tonsillectomy while in the control arm non-surgical conventional medical treatment only will be used. The primary outcome measure will be reported number of episodes of sore throat over two years with secondary outcomes measures of reported number of episodes of sore throat, otitis media and upper respiratory tract infection which invoke a GP consultation; reported number of symptom-free days; reported severity of sore throats and surgical and anaesthetic morbidity. The study will take place in five hospitals in the UK. The trial population will be 406 children aged 4-15 on their last birthday with recurrent sore throat referred by primary care to the 5 otolaryngology departments. The duration of the study is seven years (July 2001-July 2008). As with all pragmatic randomised controlled trials it is impossible to control the external environment in which the research is taking place. Since this trial began a number of factors have arisen which could affect the outcome including; a reduction in the incidence of respiratory tract infections, marked socio-economic differences in consultation rates, the results from the National Prospective Tonsillectomy Audit and the Government's waiting list initiatives.

  11. Sore throat: effective communication delivers improved diagnosis, enhanced self-care and more rational use of antibiotics.

    PubMed

    van der Velden, A W; Bell, J; Sessa, A; Duerden, M; Altiner, A

    2013-11-01

    The majority of throat infections are of viral origin and resolve without antibiotic treatment. Despite this, antibiotic use for sore throat infections remains high, partly because it is difficult to determine when antibiotics may be useful, on the basis of physical findings alone. Antibiotics may be beneficial in bacterial throat infections under certain clinical and epidemiological circumstances; however, even many of those infections in which bacteria play a role do resolve just as quickly without antibiotics. Furthermore, non-medical factors such as patient expectations and patient pressure are also important drivers of antibiotic use. To address these issues, a behavioural change is required that can be facilitated by improved communication between primary healthcare providers and patients. In this article, we provide doctors, nurses and pharmacy staff, working in primary care or in the community, with a structured approach to sore throat management, with the aim of educating and empowering patients to self-manage their condition. The first component of this approach involves identifying and addressing patients' expectations and concerns with regard to their sore throat and eliciting their opinion on antibiotics. The second part is dedicated to a pragmatic assessment of the severity of the condition, with attention to red-flag symptoms and risk factors for serious complications. Rather than just focusing on the cause (bacterial or viral) of the upper respiratory tract infections as a rationale for antibiotic use, healthcare providers should instead consider the severity of the patient's condition and whether they are at high risk of complications. The third part involves counselling patients on effective self-management options and providing information on the expected clinical course. Such a structured approach to sore throat management, using empathetic, non-paternalistic language, combined with written patient information, will help to drive patient confidence in self-care and encourage them to accept the self-limiting character of the illness - important steps towards improving antibiotic stewardship in acute throat infections. © 2013 John Wiley & Sons Ltd.

  12. Antibiotics for sore throat.

    PubMed

    Spinks, Anneliese; Glasziou, Paul P; Del Mar, Chris B

    2013-11-05

    Sore throat is a common reason for people to present for medical care. Although it remits spontaneously, primary care doctors commonly prescribe antibiotics for it. To assess the benefits of antibiotics for sore throat for patients in primary care settings. We searched CENTRAL 2013, Issue 6, MEDLINE (January 1966 to July week 1, 2013) and EMBASE (January 1990 to July 2013). Randomised controlled trials (RCTs) or quasi-RCTs of antibiotics versus control assessing typical sore throat symptoms or complications. Two review authors independently screened studies for inclusion and extracted data. We resolved differences in opinion by discussion. We contacted trial authors from three studies for additional information. We included 27 trials with 12,835 cases of sore throat. We did not identify any new trials in this 2013 update. 1. Symptoms Throat soreness and fever were reduced by about half by using antibiotics. The greatest difference was seen at day three. The number needed to treat to benefit (NNTB) to prevent one sore throat at day three was less than six; at week one it was 21. 2. Non-suppurative complications The trend was antibiotics protecting against acute glomerulonephritis but there were too few cases to be sure. Several studies found antibiotics reduced acute rheumatic fever by more than two-thirds within one month (risk ratio (RR) 0.27; 95% confidence interval (CI) 0.12 to 0.60). 3. Suppurative complications Antibiotics reduced the incidence of acute otitis media within 14 days (RR 0.30; 95% CI 0.15 to 0.58); acute sinusitis within 14 days (RR 0.48; 95% CI 0.08 to 2.76); and quinsy within two months (RR 0.15; 95% CI 0.05 to 0.47) compared to those taking placebo. 4. Subgroup analyses of symptom reduction Antibiotics were more effective against symptoms at day three (RR 0.58; 95% CI 0.48 to 0.71) if throat swabs were positive for Streptococcus, compared to RR 0.78; 95% CI 0.63 to 0.97 if negative. Similarly at week one the RR was 0.29 (95% CI 0.12 to 0.70) for positive and 0.73 (95% CI 0.50 to 1.07) for negative Streptococcus swabs. Antibiotics confer relative benefits in the treatment of sore throat. However, the absolute benefits are modest. Protecting sore throat sufferers against suppurative and non-suppurative complications in high-income countries requires treating many with antibiotics for one to benefit. This NNTB may be lower in low-income countries. Antibiotics shorten the duration of symptoms by about 16 hours overall.

  13. Neck dissection

    MedlinePlus

    ... cancer - neck dissection; Throat cancer - neck dissection; Squamous cell cancer - neck dissection ... blood cells around the body to fight infection. Cancer cells in the mouth or throat can travel in ...

  14. Rapid Detection of Enveloped Viruses.

    DTIC Science & Technology

    1988-03-12

    analysis of samples with the highest possible virus titer. Specimens were quick-frozen and stored at -700C. Throat washings were also obtained from...are throat washings performed with a veal infusion broth-gelatin mixture (2.5% V.I.B. and 0.5% gelatin in distilled water) and have been stored at -200C...enlisted the cooperation of the Director of Employee Health Services, Dr. Donald Smith, and obtained 14 throat wash specimens from Mount Sinai employees. We

  15. Anode Sheath Contributions in Plasma Thrusters

    DTIC Science & Technology

    1994-03-01

    and considerable throat erosion, is shown to be related to the electron temperature’s (T) rise above the gas temperature (To). An elementary one...surface damage and considerable throat erosion, is shown to be related to the electron temperature’s (T.) rise above the gas temperature (T.). An...Exhaust velocity is also limited hy material heating limitations of the combustion chamber and nozzle throat , and "frozen flow Losses" (unrecoverable energy

  16. Throat Culture from Patients with Meningococcal Meningitis

    DTIC Science & Technology

    1990-01-01

    THROAT CULTURE FROM PATIENTS-’WITH MENINGOCOCCAL MENINGITIS BY J.E. Sippel and N.I. Girigs U.S. NAVAL MEDICAL RESEARCH UNIT NO. 3 (CAIRO, ARAB REPUBLIC...lowv albumin eoncen rations, characteristically, have a centra fpit and are throat swabs from teenage or young dults but that it als’q underestimites...8217described would’/cletzrly facilitate recognition read at 590 tim against commensal staphylococci and strep - NP IIRENWALD The procedure is linear t thie

  17. Epidemic Outbreak Surveillance (EOS)

    DTIC Science & Technology

    2006-07-01

    Experiment to Test Integrity of2003 Nasal Wash and Throat Swab Samples Stored at -80°C. September 2005 (Sue WorthyLuke Daum) Seven matched pairs of...Nasal Wash and Throat Swab samples, previously tested in September 2004 for Influenza A, were pulled from the -80°C storage freezer for re-testing...January 2006 a detailed vrocess was completed to inventorv and organize the sample storage freezers for all Nasal wash, Throat swab and PAXgene

  18. Experimental and raytrace results for throat-to-throat compound parabolic concentrators

    NASA Technical Reports Server (NTRS)

    Leviton, D. B.; Leitch, J. W.

    1986-01-01

    Compound parabolic concentrators are nonimaging cone-shaped optics with useful angular transmission characteristics. Two cones used throat-to-throat accept radiant flux within one well-defined acceptance angle and redistribute it into another. If the entrance cone is fed with Lambertian flux, the exit cone produces a beam whose half-angle is the exit cone's acceptance angle and whose cross section shows uniform irradiance from near the exit mouth to infinity. (The pair is a beam angle transformer). The design of one pair of cones is discussed, also an experiment to map the irradiance of the emergent beam, and a raytracing program which models the cones fed by Lambertian flux. Experimental results compare favorably with raytrace results.

  19. Pharyngitis - viral

    MedlinePlus

    ... throat is due to a viral infection. The antibiotics will not help. Using them to treat viral infections helps bacteria become resistant to antibiotics. With some sore throats (such as those caused ...

  20. Pore-throat radius and tortuosity estimation from formation resistivity data for tight-gas sandstone reservoirs

    NASA Astrophysics Data System (ADS)

    Ziarani, Ali S.; Aguilera, Roberto

    2012-08-01

    A new model is proposed for estimation of pore-throat aperture size from formation resistivity factor and permeability data. The model is validated with data from the Mesaverde sandstone using brine salinities ranging from 20,000 to 200,000 ppm. The data analyzed includes various basins such as Green River, Piceance, Sand Wash, Powder River, Uinta, Washakie and Wind River, available in the literature. For pore-throat radii analysis the methodology involves the use of log-log plots of pore-throat radius versus the product of formation resistivity factor and permeability (rT = a(FK)b + c). The model fits over 280 samples from the Mesaverde formation with coefficients of determination varying between 0.95 and 0.99 depending primarily on the type of model used for pore throat radius calculation. The brine salinity has some minor effects on the results. The model can provide better estimates of pore-throat radii if it is calibrated with experimental techniques such as mercury porosimetry. The results show pore-throat radii varying between 0.001 and 5 μm for the Mesaverde tight sandstone; however, most of the samples fall in a range between 0.01 and 1 μm. For tortuosity analysis, the calculation involves the use of product of formation factor and porosity data. Results indicate that the estimated tortuosity values range mainly between 1 and 5. For samples with lower porosities (< 5%), tortuosity values show a wider scatter (between 1 and 8); whereas for samples with larger porosities (> 15%), the scattering in tortuosity decreases significantly. In general, for tortuosity calculation in tight gas sandstone formations, a square root model with a parameter (bf) representing various types of connecting pores, i.e., sheet-like and tubular pores, is recommended.

  1. Comparison of Laryngeal Mask Airway Supreme and Laryngeal Mask Airway Proseal with respect to oropharyngeal leak pressure during laparoscopic cholecystectomy: a randomised controlled trial.

    PubMed

    Beleña, José M; Núñez, Mónica; Anta, Diego; Carnero, Maria; Gracia, José L; Ayala, José L; Alvarez, Raquel; Yuste, Javier

    2013-03-01

    A comparison of the efficacy and safety of the Laryngeal Mask Airway (LMA) Supreme (LMAS) versus the LMA Proseal (LMAP) in elective laparoscopic cholecystectomy. To compare the LMAS with LMAP in terms of ventilatory efficacy, airway leak pressure (airway protection), ease-of-use and complications. Prospective, single-blind, randomised, controlled study. The Hospital del Sureste and Hospital Ramon y Cajal, Madrid, between May 2009 and March 2011. The Hospital del Sureste is a secondary hospital and Hospital Ramon y Cajal is a tertiary hospital. Patients undergoing elective laparoscopic cholecystectomy were studied following informed consent. Inclusion criteria were American Society of Anesthesiologists physical status I to III and age 18 or more. Exclusion criteria were BMI more than 40 kg m, symptomatic hiatus hernia or severe gastro-oesophageal reflux. Anaesthesiologists experienced in the use of LMAP and LMAS participated in the trial. One hundred twenty-two patients were randomly allocated to LMAS or LMAP. Our primary outcome measure was the oropharyngeal leak pressure (OLP). Secondary outcomes were the time and number of attempts for insertion, ease of insertion of the drain tube, adequacy of ventilation and the incidence of complication. Patients were interviewed postoperatively to evaluate the presence of sore throat, dysphagia or dysphonia. Two patients were excluded when surgery changed from laparoscopic to open. A total of 120 patients were finally included in the analysis. The mean OLP in the LMAP group was significantly higher than that in the LMAS group (30.7 ± 6.2 versus 26.8 ± 4.1 cmH2O;P < 0.01). This was consistent with a higher maximum tidal volume achieved with the LMAP compared to the LMAS (511 ± 68 versus 475 ± 55 ml; P = 0.04). The success rate of the first attempt insertion was higher for the LMAS group than the LMAP group (96.7 and 71.2%, respectively; P < 0.01). The time taken for insertion, ease of insertion of the drain tube, complications and postoperative pharyngolaryngeal adverse events were similar in both groups. The LMAP has a higher OLP and achieves a higher maximum tidal volume compared to the LMAS, in patients undergoing elective laparoscopic cholecystectomy. The success of the first attempt insertion was higher for the LMAS.

  2. Comparison of illumigene Group A Streptococcus Assay with Culture of Throat Swabs from Children with Sore Throats in the New Zealand School-Based Rheumatic Fever Prevention Program.

    PubMed

    Upton, Arlo; Bissessor, Liselle; Farrell, Elizabeth; Shulman, Stanford T; Zheng, Xiaotian; Lennon, Diana

    2016-01-01

    Group A streptococcal (GAS) pharyngitis is a particularly important condition in areas of New Zealand where the incidence of acute rheumatic fever remains unacceptably high. Prompt diagnosis and treatment of GAS pharyngitis are cornerstones of the Rheumatic Fever Prevention Programme, but these are hindered by the turnaround time of culture. Tests with excellent performance and rapid turnaround times are needed. For this study, throat swabs (Copan ESwabs) were collected from schoolchildren self-identifying with a sore throat. Samples were tested by routine culture and the illumigene GAS assay using loop-mediated isothermal amplification. Discrepant results were resolved by retesting of the same specimen by an alternative molecular assay. Seven hundred fifty-seven throat swab specimens were tested by both methods. The performance characteristics of the illumigene assay using culture on blood agar as the "gold standard" and following discrepancy analysis were as follows: sensitivity, 82% and 87%, respectively; specificity, 93% and 98%, respectively; positive predictive value, 61% and 88%, respectively; and negative predictive value, 97% and 97%, respectively. In our unique setting of a school-based throat swabbing program, the illumigene assay did not perform quite as well as described in previous reports. Despite this, its improved sensitivity and rapid turnaround time compared with those of culture are appealing. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Impact of an Exhaust Throat on Semi-Idealized Rotating Detonation Engine Performance

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E.

    2016-01-01

    A computational fluid dynamic (CFD) model of a rotating detonation engine (RDE) is used to examine the impact of an exhaust throat (i.e. a constriction) on performance. The model simulates an RDE which is premixed, adiabatic, inviscid, and which contains an inlet valve that prevents backflow from the high pressure region directly behind the rotating detonation. Performance is assessed in terms of ideal net specific impulse which is computed on the assumption of lossless expansion of the working fluid to the ambient pressure through a notional diverging nozzle section downstream of the throat. Such a semi-idealized analysis, while not real-world, allows the effect of the throat to be examined in isolation from, rather than coupled to (as it actually is) various loss mechanisms. For the single Mach 1.4 flight condition considered, it is found that the addition of a throat can yield a 9.4 percent increase in specific impulse. However, it is also found that when the exit throat restriction gets too small, an unstable type of operation ensues which eventually leads to the detonation failing. This behavior is found to be somewhat mitigated by the addition of an RDE inlet restriction across which there is an aerodynamic loss. Remarkably, this loss is overcome by the benefits of the further exhaust restrictions allowed. The end result is a configuration with a 10.3 percent improvement in ideal net specific thrust.

  4. Impact of an Exhaust Throat on Semi-Idealized Rotating Detonation Engine Performance

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E.

    2016-01-01

    A computational fluid dynamic (CFD) model of a rotating detonation engine (RDE) is used to examine the impact of an exhaust throat (i.e., a constriction) on performance. The model simulates an RDE which is premixed, adiabatic, inviscid, and which contains an inlet valve that prevents backflow from the high pressure region directly behind the rotating detonation. Performance is assessed in terms of ideal net specific impulse which is computed on the assumption of lossless expansion of the working fluid to the ambient pressure through a notional diverging nozzle section downstream of the throat. Such a semi-idealized analysis, while not real-world, allows the effect of the throat to be examined in isolation from, rather than coupled to (as it actually is) various loss mechanisms. For the single Mach 1.4 flight condition considered, it is found that the addition of a throat can yield a 9.4 percent increase in specific impulse. However, it is also found that when the exit throat restriction gets too small, an unstable type of operation ensues which eventually leads to the detonation failing. This behavior is found to be somewhat mitigated by the addition of an RDE inlet restriction across which there is an aerodynamic loss. Remarkably, this loss is overcome by the benefits of the further exhaust restrictions allowed. The end result is a configuration with a 10.3 percent improvement in ideal net specific thrust.

  5. Vocal Tract Discomfort and Risk Factors in University Teachers.

    PubMed

    Korn, Gustavo Polacow; Augusto de Lima Pontes, Antonio; Abranches, Denise; Augusto de Lima Pontes, Paulo

    2016-07-01

    To characterize the presence of and risk factors for throat pain or irritation among male and female university teachers in private institutions within the city of São Paulo. This is a cross-sectional survey. Voice self-evaluation forms prepared by the Brazilian Ministry of Labor were administered to 846 university teachers in a private institution in the city of São Paulo, Brazil. The prevalence of throat pain or irritation was 50.8% and was higher in the women (62.7%) than in the men (43.5%). The prevalence of throat pain or irritation was higher among professionals ≤60 years old and among those who spent most of their time teaching compared with those who spent most of their time performing other professional activities. Other factors, such as noise and sound competition, air pollution, stress and anxiety, personal habits, and lifestyle/quality of life, were related to the presence of throat pain or irritation. University teachers demonstrated a high prevalence of throat pain or irritation. Factors such as age ≤60 years, female gender, time-consuming professional activities, noise and sound competition in the work environment, stress and anxiety, air pollution, access to water, personal habits, and lifestyle/quality of life were related to the presence of throat pain or irritation. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  6. Plantar loading during cutting while wearing a rigid carbon fiber insert.

    PubMed

    Queen, Robin M; Abbey, Alicia N; Verma, Ravi; Butler, Robert J; Nunley, James A

    2014-01-01

    Stress fractures are one of the most common injuries in sports, accounting for approximately 10% of all overuse injuries. Treatment of fifth metatarsal stress fractures involves both surgical and nonsurgical interventions. Fifth metatarsal stress fractures are difficult to treat because of the risks of delayed union, nonunion, and recurrent injuries. Most of these injuries occur during agility tasks, such as those performed in soccer, basketball, and lacrosse. To examine the effect of a rigid carbon graphite footplate on plantar loading during 2 agility tasks. Crossover study. Laboratory. A total of 19 recreational male athletes with no history of lower extremity injury in the past 6 months and no previous metatarsal stress fractures were tested. Seven 45° side-cut and crossover-cut tasks were completed in a shoe with or without a full-length rigid carbon plate. Testing order between the shoe conditions and the 2 cutting tasks was randomized. Plantar-loading data were recorded using instrumented insoles. Peak pressure, maximum force, force-time integral, and contact area beneath the total foot, the medial and lateral midfoot, and the medial, middle, and lateral forefoot were analyzed. A series of paired t tests was used to examine differences between the footwear conditions (carbon graphite footplate, shod) for both cutting tasks independently (α = .05). During the side-cut task, the footplate increased total foot and lateral midfoot peak pressures while decreasing contact area and lateral midfoot force-time integral. During the crossover-cut task, the footplate increased total foot and lateral midfoot peak pressure and lateral forefoot force-time integral while decreasing total and lateral forefoot contact area. Although a rigid carbon graphite footplate altered some aspects of the plantar-pressure profile during cutting in uninjured participants, it was ineffective in reducing plantar loading beneath the fifth metatarsal.

  7. Multi-Physics Simulation of TREAT Kinetics using MAMMOTH

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

    DeHart, Mark; Gleicher, Frederick; Ortensi, Javier

    With the advent of next generation reactor systems and new fuel designs, the U.S. Department of Energy (DOE) has identified the need for the resumption of transient testing of nuclear fuels. DOE has decided that the Transient Reactor Test Facility (TREAT) at Idaho National Laboratory (INL) is best suited for future testing. TREAT is a thermal neutron spectrum nuclear test facility that is designed to test nuclear fuels in transient scenarios. These specific fuels transient tests range from simple temperature transients to full fuel melt accidents. The current TREAT core is driven by highly enriched uranium (HEU) dispersed in amore » graphite matrix (1:10000 U-235/C atom ratio). At the center of the core, fuel is removed allowing for the insertion of an experimental test vehicle. TREAT’s design provides experimental flexibility and inherent safety during neutron pulsing. This safety stems from the graphite in the driver fuel having a strong negative temperature coefficient of reactivity resulting from a thermal Maxwellian shift with increased leakage, as well as graphite acting as a temperature sink. Air cooling is available, but is generally used post-transient for heat removal. DOE and INL have expressed a desire to develop a simulation capability that will accurately model the experiments before they are irradiated at the facility, with an emphasis on effective and safe operation while minimizing experimental time and cost. At INL, the Multi-physics Object Oriented Simulation Environment (MOOSE) has been selected as the model development framework for this work. This paper describes the results of preliminary simulations of a TREAT fuel element under transient conditions using the MOOSE-based MAMMOTH reactor physics tool.« less

  8. Soft X-ray emission spectroscopy of liquids and lithium batterymaterials

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

    Augustsson, Andreas

    2004-01-01

    Lithium ion insertion into electrode materials is commonly used in rechargeable battery technology. The insertion implies changes in both the crystal structure and the electronic structure of the electrode material. Side-reactions may occur on the surface of the electrode which is exposed to the electrolyte and form a solid electrolyte interface (SEI). The understanding of these processes is of great importance for improving battery performance. The chemical and physical properties of water and alcohols are complicated by the presence of strong hydrogen bonding. Various experimental techniques have been used to study geometrical structures and different models have been proposed tomore » view the details of how these liquids are geometrically organized by hydrogen bonding. However, very little is known about the electronic structure of these liquids, mainly due to the lack of suitable experimental tools. In this thesis examples of studies of lithium battery electrodes and liquid systems using soft x-ray emission spectroscopy will be presented. Monochromatized synchrotron radiation has been used to accomplish selective excitation, in terms of energy and polarization. The electronic structure of graphite electrodes has been studied, before and after lithium intercalation. Changes in the electronic structure upon lithiation due to transfer of electrons into the graphite π-bands have been observed. Transfer of electrons in to the 3d states of transition metal oxides upon lithiation have been studied, through low energy excitations as dd- and charge transfer-excitations. A SEI was detected on cycled graphite electrodes. By the use of selective excitation different carbon sites were probed in the SEI. The local electronic structure of water, methanol and mixtures of the two have been examined using a special liquid cell, to separate the liquid from the vacuum in the experimental chamber. Results from the study of liquid water showed a strong influence on the 3a1 molecular orbital and orbital mixing between water molecules upon hydrogen bonding. Apart from the four-hydrogen-bonding structure in water, a structure where one hydrogen bond is broken could be separated and identified. The soft x-ray emission study of methanol showed the existence of ring and chain formations in the liquid phase and the dominating structures are formed of 6 and 8 molecules. Upon mixing of the two liquids, a segregation at the molecular level was found and the formation of new structures, which could explain the unexpected low increase of the entropy.« less

  9. Osteochondrodysplasias

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  10. Osteopetroses

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  11. An algorithm for a selective use of throat swabs in the diagnosis of group A streptococcal pharyngo-tonsillitis in general practice.

    PubMed

    Hoffmann, S

    1992-12-01

    A prospective evaluation was made of an algorithm for a selective use of throat swabs in patients with sore throat in general practice. The algorithm states that a throat swab should be obtained (a) in all children younger than 15 years; (b) in patients aged 15 years or more who have pain on swallowing and at least three of four signs (enlarged or hyperaemic tonsils; exudate; enlarged or tender angular lymph nodes; and a temperature > or = 38 degrees C); and (c) in adults aged 15-44 years with pain on swallowing and one or two of the four signs, but not both cough and coryza. Group A streptococci were found by laboratory culture in 30% of throat swabs from 1783 patients. Using these results as the reference, the algorithm was 95% sensitive and 26% specific, and assigned 80% of the patients to be swabbed. Its positive and negative predictive values in this setting were 36% and 92%, respectively. It is concluded that this algorithm may be useful in general practice.

  12. Female Preference for Sympatric vs. Allopatric Male Throat Color Morphs in the Mesquite Lizard (Sceloporus grammicus) Species Complex

    PubMed Central

    Bastiaans, Elizabeth; Bastiaans, Mary Jane; Morinaga, Gen; Castañeda Gaytán, José Gamaliel; Marshall, Jonathon C.; Bane, Brendan; de la Cruz, Fausto Méndez; Sinervo, Barry

    2014-01-01

    Color polymorphic sexual signals are often associated with alternative reproductive behaviors within populations, and the number, frequency, or type of morphs present often vary among populations. When these differences lead to assortative mating by population, the study of such polymorphic taxa may shed light on speciation mechanisms. We studied two populations of a lizard with polymorphic throat color, an important sexual signal. Males in one population exhibit orange, yellow, or blue throats; whereas males in the other exhibit orange, yellow, or white throats. We assessed female behavior when choosing between allopatric and sympatric males. We asked whether females discriminated more when the allopatric male was of an unfamiliar morph than when the allopatric male was similar in coloration to the sympatric male. We found that female rejection of allopatric males relative to sympatric males was more pronounced when males in a pair were more different in throat color. Our findings may help illuminate how behavioral responses to color morph differences between populations with polymorphic sexual signals contribute to reproductive isolation. PMID:24718297

  13. Reactor pressure vessel nozzle

    DOEpatents

    Challberg, Roy C.; Upton, Hubert A.

    1994-01-01

    A nozzle for joining a pool of water to a nuclear reactor pressure vessel includes a tubular body having a proximal end joinable to the pressure vessel and a distal end joinable in flow communication with the pool. The body includes a flow passage therethrough having in serial flow communication a first port at the distal end, a throat spaced axially from the first port, a conical channel extending axially from the throat, and a second port at the proximal end which is joinable in flow communication with the pressure vessel. The inner diameter of the flow passage decreases from the first port to the throat and then increases along the conical channel to the second port. In this way, the conical channel acts as a diverging channel or diffuser in the forward flow direction from the first port to the second port for recovering pressure due to the flow restriction provided by the throat. In the backflow direction from the second port to the first port, the conical channel is a converging channel and with the abrupt increase in flow area from the throat to the first port collectively increase resistance to flow therethrough.

  14. Experimental study of moving throat plug in a shock tunnel

    NASA Astrophysics Data System (ADS)

    Lee, J. K.; Park, C.; Kwon, O. J.

    2015-07-01

    An experimental study has been carried out to investigate the flow in the KAIST shock tunnel with two moving throat plugs at a primary shock velocity of 1.19 km/s. The nozzle reservoir pressure and the Pitot pressure at the exit of the nozzle were measured to examine the influence of the moving throat plugs on the shock tunnel flow. To assess the present experimental results, comparisons with previous work using a stationary throat plug were made. The mechanism for closing the moving throat plug was developed and verified. The source of the force to move the plug was the pressure generated when the primary shock was reflected at the bottom of the plug. It was observed that the two plugs terminated the shock tunnel flow after the steady flow. .The time for the plugs to terminate the flow showed good agreement with the calculation of the proposed simple analytic solution. There was a negligible difference in flow values such as the reflected pressure and the Pitot pressure between the moving and the stationary plugs.

  15. Congestive Hepatomegaly

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  16. Cutis Laxa

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  17. Bacterial Tracheitis

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  18. Transpiration cooled throat for hydrocarbon rocket engines

    NASA Technical Reports Server (NTRS)

    May, Lee R.; Burkhardt, Wendel M.

    1991-01-01

    The objective for the Transpiration Cooled Throat for Hydrocarbon Rocket Engines Program was to characterize the use of hydrocarbon fuels as transpiration coolants for rocket nozzle throats. The hydrocarbon fuels investigated in this program were RP-1 and methane. To adequately characterize the above transpiration coolants, a program was planned which would (1) predict engine system performance and life enhancements due to transpiration cooling of the throat region using analytical models, anchored with available data; (2) a versatile transpiration cooled subscale rocket thrust chamber was designed and fabricated; (3) the subscale thrust chamber was tested over a limited range of conditions, e.g., coolant type, chamber pressure, transpiration cooled length, and coolant flow rate; and (4) detailed data analyses were conducted to determine the relationship between the key performance and life enhancement variables.

  19. Tonsillitis

    MedlinePlus

    ... A bacterial or viral infection can cause tonsillitis. Strep throat is a common cause. The infection may also ... days after you start the antibiotics. Children with strep throat should be kept home from school or day ...

  20. Biological Resources Survey of Mountain Springs Canyon on the Naval Weapons Center.

    DTIC Science & Technology

    1983-03-01

    Black -headed Grosbeak m Lazuli Bunting b House Finch a Lesser Goldfinch b Inyo Brown Towhee b Black - throated Sparrow a...Scott’s Oriole 1.5 House Finch 30.3 Black - throated Sparrow 3.3 66.8 Sage Sparrow 2.3 4.5 Brewer’s Sparrow 181.0 105.8 AVERAGE PAIRS/40 ha 286.4 200.1...Pipilo fuscus eremoghilus Rufous-crowned Sparrow 2 Almophila ruflceps Black - throated Sparrow Amahispiza bilineata 78 I NWC TP 6424 I Table

  1. Ecological Assessment of the Effects of Army Training Activities on a Desert Ecosystem. National Training Center, Fort Irwin, California

    DTIC Science & Technology

    1985-06-01

    predators .) Several bird species ( black - throated sparrows , LeConte’s...7.3 7.7 12.5 33 28 23 24 39 Black - throated Sparrow - Amphispiza bilineata 5.0 0.3 6.7 7.7 4.5 16 1 21 24 14 Brewer’s Sparrow - Spizella breweri 6.5 0...identified as sensitive indicators of disturbances. The absence of black - throated sparrows and LeConte’s thrashers * indicate severely degraded habitats.

  2. Dual nozzle aerodynamic and cooling analysis study. [dual throat and dual expander nozzles

    NASA Technical Reports Server (NTRS)

    Meagher, G. M.

    1980-01-01

    Geometric, aerodynamic flow field, performance prediction, and heat transfer analyses are considered for two advanced chamber nozzle concepts applicable to Earth-to-orbit engine systems. Topics covered include improvements to the dual throat aerodynamic and performance prediction program; geometric and flow field analyses of the dual expander concept; heat transfer analysis of both concepts, and engineering analysis of data from the NASA/MSFC hot-fire testing of a dual throat thruster model thrust chamber assembly. Preliminary results obtained are presented in graphs.

  3. Construction and test of flexible walls for the throat of the ILR high-speed wind tunnel

    NASA Technical Reports Server (NTRS)

    Igeta, Y.

    1983-01-01

    Aerodynamic tests in wind tunnels are jeopardized by the lateral limitations of the throat. This influence expands with increasing size of the model in proportion to the cross-section of the throat. Wall interference of this type can be avoided by giving the wall the form of a stream surface that would be identical to the one observed during free flight. To solve this problem, flexible walls that can adapt to every contour of surface flow are needed.

  4. Some tests on small-scale rectangular throat ejector. [thrust augmentation for V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Dean, W. N., Jr.; Franke, M. E.

    1979-01-01

    A small scale rectangular throat ejector with plane slot nozzles and a fixed throat area was tested to determine the effects of diffuser sidewall length, diffuser area ratio, and sidewall nozzle position on thrust and mass augmentation. The thrust augmentation ratio varied from approximately 0.9 to 1.1. Although the ejector did not have good thrust augmentation performance, the effects of the parameters studied are believed to indicate probable trends in thrust augmenting ejectors.

  5. Fast acting multiple element valve

    DOEpatents

    Yang, Jefferson Y. S.; Wada, James M.

    1991-01-01

    A plurality of slide valve elements having plural axial-spaced annular parts and an internal slide are inserted into a bulkhead in a fluid conduit from a downstream side of the bulkhead, locked in place by a bayonet coupling and set screw, and project through the bulkhead into the upstream conduit. Pneumatic lines connecting the slide valve element actuator to pilot valves are brought out the throat of the valve element to the downstream side. Pilot valves are radially spaced around the exterior of the valve to permit the pneumatic lines to be made identical, thereby to minimize adverse timing tolerances in operation due to pressure variations. Ring manifolds surround the valve adjacent respective pilot valve arrangements to further reduce adverse timing tolerances due to pressure variations, the manifolds being directly connected to the respective pilot valves. Position sensors are provided the valve element slides to signal the precise time at which a slide reaches or passes through a particular point in its stroke to initiate a calibrated timing function.

  6. Nickel-Graphite Composite Compliant Interface and/or Hot Shoe Material

    NASA Technical Reports Server (NTRS)

    Firdosy, Samad A.; Chun-Yip Li, Billy; Ravi, Vilupanur A.; Fleurial, Jean-Pierre; Caillat, Thierry; Anjunyan, Harut

    2013-01-01

    Next-generation high-temperature thermoelectric-power-generating devices will employ segmented architectures and will have to reliably withstand thermally induced mechanical stresses produced during component fabrication, device assembly, and operation. Thermoelectric materials have typically poor mechanical strength, exhibit brittle behavior, and possess a wide range of coefficient of thermal expansion (CTE) values. As a result, the direct bonding at elevated temperatures of these materials to each other to produce segmented leg components is difficult, and often results in localized microcracking at interfaces and mec hanical failure due to the stresses that arise from the CTE mismatch between the various materials. Even in the absence of full mechanical failure, degraded interfaces can lead to increased electrical and thermal resistances, which adversely impact conversion efficiency and power output. The proposed solution is the insertion of a mechanically compliant layer, with high electrical and thermal conductivity, between the low- and high-temperature segments to relieve thermomechanical stresses during device fabrication and operation. This composite material can be used as a stress-relieving layer between the thermoelectric segments and/or between a thermoelectric segment and a hot- or cold-side interconnect material. The material also can be used as a compliant hot shoe. Nickel-coated graphite powders were hot-pressed to form a nickel-graphite composite material. A freestanding thermoelectric segmented leg was fabricated by brazing the compliant pad layer between the high-temperature p- Zintl and low-temperature p-SKD TE segments using Cu-Ag braze foils. The segmented leg stack was heated in vacuum under a compressive load to achieve bonding. The novelty of the innovation is the use of composite material that re duces the thermomechanical stresses en - countered in the construction of high-efficiency, high-temperature therm - o-electric devices. The compliant pad enables the bonding of dissimilar thermoelectric materials while maintaining the desired electrical and thermal properties essential for efficient device operation. The modulus, CTE, electrical, and thermal conductances of the composite can be controlled by varying the ratio of nickel to graphite.

  7. Anemia in the Newborn

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  8. Birth Injury in Newborns

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  9. Prospective surveillance of streptococcal sore throat in a tropical country.

    PubMed

    Steer, Andrew C; Jenney, Adam W J; Kado, Joseph; Good, Michael F; Batzloff, Michael; Magor, Graham; Ritika, Roselyn; Mulholland, Kim E; Carapetis, Jonathan R

    2009-06-01

    Acute rheumatic fever and rheumatic heart disease cause a high burden of disease in Fiji and surrounding Pacific Island countries, but little is known about the epidemiology of group A streptococcal (GAS) pharyngitis in the region. We designed a study to estimate the prevalence of carriage of beta-hemolytic streptococci (BHS) and the incidence of BHS culture-positive sore throat in school aged children in Fiji. We conducted twice-weekly prospective surveillance of school children aged 5 to 14 years in 4 schools in Fiji during a 9-month period in 2006, after an initial phase of pharyngeal swabbing to determine the prevalence of BHS carriage. We enrolled 685 children. The prevalence of GAS carriage was 6.0%, while the prevalence of group C streptococcal (GCS) and group G streptococcal (GGS) carriage was 6.9% and 12%, respectively. There were 61 episodes of GAS culture-positive sore throat during the study period equating to an incidence of 14.7 cases per 100 child-years (95% CI, 11.2-18.8). The incidence of GCS/GGS culture-positive sore throat was 28.8 cases per 100 child-years (95% CI, 23.9-34.5). The clinical nature of GAS culture-positive sore throat was more severe than culture-negative sore throat, but overall was mild compared with that found in previous studies. Of the 101 GAS isolates that emm sequence typed there were 45 emm types with no dominant types. There were very few emm types commonly encountered in industrialized nations and only 9 of the 45 emm types found in this study are emm types included in the 26-valent GAS vaccine undergoing clinical trials. GAS culture-positive sore throat was more common than expected. Group C and group G streptococci were frequently isolated in throat cultures, although their contribution to pharyngeal infection is not clear. The molecular epidemiology of pharyngeal GAS in our study differed greatly from that in industrialized nations and this has implications for GAS vaccine clinical research in Fiji and other tropical developing countries.

  10. A Study to Determine if Addition of Palatal Petechiae to Centor Criteria Adds More Significance to Clinical Diagnosis of Acute Strep Pharyngitis in Children.

    PubMed

    Nibhanipudi, Kumara V

    2016-01-01

    Objective. A study to determine if addition of palatal petechiae to Centor criteria adds more value for clinical diagnosis of acute strep pharyngitis in children. Hypothesis. In children, Centor Criteria does not cover all the symptoms and signs of acute strep pharyngitis. We hypothesize that addition of palatal petechiae to Centor Criteria will increase the possibility of clinical diagnosis of group A streptococcal pharyngitis in children. Methods. One hundred patients with a complaint of sore throat were enrolled in the study. All the patients were examined clinically using the Centor Criteria. They were also examined for other signs and symptoms like petechial lesions over the palate, abdominal pain, and skin rash. All the patients were given rapid strep tests, and throat cultures were sent. No antibiotics were given until culture results were obtained. Results. The sample size was 100 patients. All 100 had fever, sore throat, and erythema of tonsils. Twenty of the 100 patients had tonsillar exudates, 85/100 had tender anterior cervical lymph nodes, and 86/100 had no cough. In total, 9 out of the 100 patients had positive throat cultures. We observed that petechiae over the palate, a very significant sign, is not included in the Centor Criteria. Palatal petechiae were present in 8 out of the 100 patients. Six out of these 8 with palatal petechiae had positive throat culture for strep (75%). Only 7 out of 20 with exudates had positive strep culture. Sixteen out of the 100 patients had rapid strep test positive. Those 84/100 who had negative rapid strep also had negative throat culture. Statistics. We used Fisher's exact test, comparing throat culture positive and negative versus presence of exudates and palatal hemorrhages with positive and negative throat cultures and the resultant P value <.0001. Conclusion. Our study concludes that addition of petechiae over the palate to Centor Criteria will increase the possibility of diagnosing acute group A streptococcal pharyngitis in children.

  11. Ceramic materials under high temperature heat transfer conditions

    NASA Astrophysics Data System (ADS)

    Mittenbühler, A.; Jung, J.

    1990-04-01

    Ceramic materials for application in a High-Temperature Reactor coupled with the steam gasification of coal were investigated. The study concentrated on the hot gas duct and their thermal insulation. Materials examined for the inner lining of the tubes were graphite, carbon fibre reinforced carbon and amorphous silica, while fibres, porous alumina and bonded alumina fibres were tested as insulating materials. During material investigations qualification was performed on samples and in component tests. For two carbon fibre reinforced carbon qualities with different graphitizing temperatures, the bending strength was determined as a function of volume corrosion. Devitrification of amorphous silica can be tolerated up to operating temperatures of about 950°C. The resilience of fibre materials depends on the Al2O3/ SiO2 ratio. It decreases according to the different fibre composition with increasing temperature and limits the maximum operating temperature for long term operation. The porous hollow spherical corundum inserted in the form of bricks fulfilled the thermal shock and mechanical requirements but led to an insulation exhibiting gaps in component tests. An advanced insulation on the basis of bonded alumina fibre showed a quasi-elastic material behaviour. Resistance to abrasion was achieved with a protective ceramic coating. The different materials and design concepts are compared and the results provide a good solution for the project.

  12. Ultrasound-Assisted Emulsification Microextraction Based on Solidification Floating Organic Drop Trace Amounts of Manganese Prior to Graphite Furnace Atomic Absorption Spectrometry Determination

    PubMed Central

    Mohadesi, Alireza; Falahnejad, Masoumeh

    2012-01-01

    In the present study, an ultrasound-assisted emulsification microextraction based on solidification floating organic drop method is described for preconcentration of trace amounts of Mn (II). 2-(5-Bromo-2-pyridylazo)-5 diethylaminophenol was added to a solution of Mn+2 at ph = 10.0. After this, 1-undecanol was added to the solution as an extraction solvent, and solution was stirred. Several factors influencing the microextraction efficiency, such as pH, the amount of chelating agent, nature and volume of extraction solvent, the volume of sample solution, stirring rate, and extraction time were investigated and optimized. Then sample vial was cooled by inserting into an ice bath, and the solidified was transferred into a suitable vial for immediate melting. Finally the sample was injected into a graphite furnace atomic absorption spectrometry. Under the optimum condition the linear dynamic range was 0.50–10.0 ng mL−1 with a correlation coefficient of 0.9926, and the detection limit of 0.3 ng mL−1 was obtained. The enrichment factor was 160. The proposed method was successfully applied for separation and determination of manganese in sea, rain, tap, and river water samples. PMID:22645504

  13. Fabricating solid carbon porous electrodes from powders

    DOEpatents

    Kaschmitter, James L.; Tran, Tri D.; Feikert, John H.; Mayer, Steven T.

    1997-01-01

    Fabrication of conductive solid porous carbon electrodes for use in batteries, double layer capacitors, fuel cells, capacitive dionization, and waste treatment. Electrodes fabricated from low surface area (<50 m.sup.2 /gm) graphite and cokes exhibit excellent reversible lithium intercalation characteristics, making them ideal for use as anodes in high voltage lithium insertion (lithium-ion) batteries. Electrodes having a higher surface area, fabricated from powdered carbon blacks, such as carbon aerogel powder, carbon aerogel microspheres, activated carbons, etc. yield high conductivity carbon compositives with excellent double layer capacity, and can be used in double layer capacitors, or for capacitive deionization and/or waste treatment of liquid streams. By adding metallic catalysts to be high surface area carbons, fuel cell electrodes can be produced.

  14. Fabricating solid carbon porous electrodes from powders

    DOEpatents

    Kaschmitter, J.L.; Tran, T.D.; Feikert, J.H.; Mayer, S.T.

    1997-06-10

    Fabrication is described for conductive solid porous carbon electrodes for use in batteries, double layer capacitors, fuel cells, capacitive deionization, and waste treatment. Electrodes fabricated from low surface area (<50 m{sup 2}/gm) graphite and cokes exhibit excellent reversible lithium intercalation characteristics, making them ideal for use as anodes in high voltage lithium insertion (lithium-ion) batteries. Electrodes having a higher surface area, fabricated from powdered carbon blacks, such as carbon aerogel powder, carbon aerogel microspheres, activated carbons, etc. yield high conductivity carbon composites with excellent double layer capacity, and can be used in double layer capacitors, or for capacitive deionization and/or waste treatment of liquid streams. By adding metallic catalysts to high surface area carbons, fuel cell electrodes can be produced. 1 fig.

  15. Large for Gestational Age (LGA)

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  16. Disorders of Amino Acid Metabolism

    MedlinePlus

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  17. Tonsillitis (For Teens)

    MedlinePlus

    ... bacteria are causing the infection. If you have strep throat , you'll need treatment with an antibiotic to ... prevent other problems that can come from untreated strep throat. If your doctor prescribes antibiotics, be sure to ...

  18. What's a Nice Hummingbird Like You Doing at an AGU Meeting Like This? (or, Operation RubyThroat Meets The GLOBE Program)

    NASA Astrophysics Data System (ADS)

    Hilton, B.

    2003-12-01

    "Operation RubyThroat: The Hummingbird Project" is an international cross-disciplinary initiative that uses Ruby-throated Hummingbirds (Archilochus colubris) as a hook to excite K-12 students (and adults) about science learning. In 2002, Operation RubyThroat affiliated with The GLOBE Program as the first GLOBE protocol that involves animal behavior. Through Operation RubyThroat, students make observations about hummingbird phenology, behavior, and ecology and correlate their data against traditional GLOBE observations of atmosphere, climate, land cover, soils, hydrology, and phenology. Although Ruby-throated Hummingbirds (RTHUs) breed throughout the eastern half of the United States and southern Canada and may be the most common and most widely distributed of all 338 hummingbird species, little is known about how abiotic environmental factors affect their migration, nesting activities, and everyday behavior. Operation RubyThroat participants in the U.S. and Canada log early arrival dates of RTHUs during spring migration, note their presence throughout the breeding season, and report the last date RTHUs are seen in autumn. Conversely, participants in Mexico and all seven Central American countries (the region in which RTHUs spend their non-breeding months) watch for early arrivals in fall and late departures in spring. Participants also attempt to estimate numbers of RTHUs in local populations by counting the number of visits hummingbirds make to feeders and/or flowers in a 45-minute time block. Optional activities include observations of RTHU nesting behaviors and determining RTHU preferences for various species of native and exotic nectar sources. Participating schools are encouraged to establish Schoolyard Hummingbird Habitats in which to make their observations, but data may be collected in backyards or at local parks, nature centers, botanical gardens, and other sites where RTHUs occur. Adults not affiliated with K-12 schools are invited to become certified in the hummingbird protocols and to submit Operation RubyThroat data to GLOBE. Participants report sightings of any RTHUs that are banded and color-marked with dye or that have unusual plumage (albinistic, leucistic, etc.). Participants in the eastern U.S. and Canada also report the occurrence of "winter vagrant" hummingbirds, i.e., species from the western U. S. and Mexico that from August through March seem to be wandering more frequently into the region. These unusual movements by western hummingbird species, as well as migration timing and winter occurrences of RTHUs, are correlated against GLOBE data to determine possible effects of atmosphere, climate, and land use, including the impact of global warming. As a new GLOBE protocol, Operation RubyThroat is just beginning to generate data for analysis. Operation RubyThroat's collaboration with GLOBE is funded by a grant from the National Science Foundation. Support for other aspects of the project comes from, among others, Agilent Technologies, ConocoPhillips (through National Fish and Wildlife Foundation), The Christensen Fund, and individual donors. Operation RubyThroat is an education, research, and conservation initiative of Hilton Pond Center for Piedmont Natural History (www.hiltonpond.org) in York, South Carolina USA.

  19. Thermo-mechanical analysis of a user filter assembly for undulator/wiggler operations at the Advanced Photon Source

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

    Nian, H.L.T.; Kuzay, T.M.; Collins, J.

    1996-12-31

    This paper reports a thermo-mechanical study of a beamline filter (user filter) for undulator/wiggler operations. It is deployed in conjunction with the current commissioning window assembly on the APS insertion device (ID) front ends. The beamline filter at the Advanced Photon Source (APS) will eventually be used in windowless operations also. Hence survival and reasonable life expectancy of the filters under intense insertion device (ID) heat flu are crucial to the beamline operations. To accommodate various user requirements, the filter is configured to be a multi-choice type and smart to allow only those filter combinations that will be safe tomore » operate with a given ring current and beamline insertion device gap. However, this paper addresses only the thermo-mechanical analysis of individual filter integrity and safety in all combinations possible. The current filter design is configured to have four filter frames in a cascade with each frame holding five filters. This allows a potential 625 total filter combinations. Thermal analysis for all of these combinations becomes a mammoth task considering the desired choices for filter materials (pyrolitic graphite and metallic filters), filter thicknesses, undulator gaps, and the beam currents. The paper addresses how this difficult task has been reduced to a reasonable effort and computational level. Results from thermo-mechanical analyses of the filter combinations are presented both in tabular and graphical format.« less

  20. Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene

    PubMed Central

    Canty, Russell; Gonzalez, Edwin; MacDonald, Caleb; Osswald, Sebastian; Zea, Hugo; Luhrs, Claudia C.

    2015-01-01

    Graphene sheets doped with nitrogen were produced by the reduction-expansion (RES) method utilizing graphite oxide (GO) and urea as precursor materials. The simultaneous graphene generation and nitrogen insertion reactions are based on the fact that urea decomposes upon heating to release reducing gases. The volatile byproducts perform two primary functions: (i) promoting the reduction of the GO and (ii) providing the nitrogen to be inserted in situ as the graphene structure is created. Samples with diverse urea/GO mass ratios were treated at 800 °C in inert atmosphere to generate graphene with diverse microstructural characteristics and levels of nitrogen doping. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to study the microstructural features of the products. The effects of doping on the samples structure and surface area were studied by X-ray diffraction (XRD), Raman Spectroscopy, and Brunauer Emmet Teller (BET). The GO and urea decomposition-reduction process as well as nitrogen-doped graphene stability were studied by thermogravimetric analysis (TGA) coupled with mass spectroscopy (MS) analysis of the evolved gases. Results show that the proposed method offers a high level of control over the amount of nitrogen inserted in the graphene and may be used alternatively to control its surface area. To demonstrate the practical relevance of these findings, as-produced samples were used as electrodes in supercapacitor and battery devices and compared with conventional, thermally exfoliated graphene. PMID:28793618

  1. Strep Test: Rapid (For Parents)

    MedlinePlus

    ... third of negative rapid strep test results are false (meaning someone actually has a strep throat infection even though the rapid strep results were negative). A throat culture may then be done to ensure accuracy. Risks ...

  2. Cariprazine

    MedlinePlus

    ... severe muscle stiffness muscle weakness or aching blank facial expression difficulty swallowing or breathing tightness in the throat tongue that sticks out of the mouth rash itching hives swelling of the face, throat, tongue, lips, or eyes dark or cola- ...

  3. Enlarged Adenoids (For Parents)

    MedlinePlus

    ... topic for: Parents Kids Teens Tonsils and Tonsillectomies Strep Throat Obstructive Sleep Apnea Preparing Your Child for Surgery ... the Operating Room? Snoring Tonsillitis All About Adenoids Strep Throat Enlarged Adenoids Tonsils and Tonsillectomies What's It Like ...

  4. Polymer quantization of the Einstein-Rosen wormhole throat

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

    Kunstatter, Gabor; Peltola, Ari; Louko, Jorma

    2010-01-15

    We present a polymer quantization of spherically symmetric Einstein gravity in which the polymerized variable is the area of the Einstein-Rosen wormhole throat. In the classical polymer theory, the singularity is replaced by a bounce at a radius that depends on the polymerization scale. In the polymer quantum theory, we show numerically that the area spectrum is evenly spaced and in agreement with a Bohr-Sommerfeld semiclassical estimate, and this spectrum is not qualitatively sensitive to issues of factor ordering or boundary conditions except in the lowest few eigenvalues. In the limit of small polymerization scale we recover, within the numericalmore » accuracy, the area spectrum obtained from a Schroedinger quantization of the wormhole throat dynamics. The prospects of recovering from the polymer throat theory a full quantum-corrected spacetime are discussed.« less

  5. CONTROL OF STREPTOCOCCAL THROAT INFECTIONS IN SCHOOLS—A Cooperative Program Followed in Orange County

    PubMed Central

    Russell, Edward Lee

    1956-01-01

    Attempts to identify streptococcal throat infections on clinical evidence alone do not provide an adequate or reliable index of the prevalence of these infections in the community. Epidemiologic information on streptococcal throat infections based on bacteriological identification permits a more accurate assessment of the situation and more logical and more effective control measures. Recent refinements in laboratory procedures have provided a simple, reliable and relatively inexpensive method for the identification of Group A beta hemolytic streptococci by public health or clinical laboratories. In Orange County a program for the identification of streptococcal throat infections by cooperative action of the medical profession, the health department and the school authorities greatly aided in control of the disease. A voluntary health agency (heart association) made an important contribution toward the success of the control program. PMID:13374555

  6. Changes in the pore network structure of Hanford sediment after reaction with caustic tank wastes.

    PubMed

    Crandell, L E; Peters, C A; Um, W; Jones, K W; Lindquist, W B

    2012-04-01

    At the former nuclear weapon production site in Hanford, WA, caustic radioactive tank waste leaks into subsurface sediments and causes dissolution of quartz and aluminosilicate minerals, and precipitation of sodalite and cancrinite. This work examines changes in pore structure due to these reactions in a previously-conducted column experiment. The column was sectioned and 2D images of the pore space were generated using backscattered electron microscopy and energy dispersive X-ray spectroscopy. A pre-precipitation scenario was created by digitally removing mineral matter identified as secondary precipitates. Porosity, determined by segmenting the images to distinguish pore space from mineral matter, was up to 0.11 less after reaction. Erosion-dilation analysis was used to compute pore and throat size distributions. Images with precipitation had more small and fewer large pores. Precipitation decreased throat sizes and the abundance of large throats. These findings agree with previous findings based on 3D X-ray CMT imaging, observing decreased porosity, clogging of small throats, and little change in large throats. However, 2D imaging found an increase in small pores, mainly in intragranular regions or below the resolution of the 3D images. Also, an increase in large pores observed via 3D imaging was not observed in the 2D analysis. Changes in flow conducting throats that are the key permeability-controlling features were observed in both methods. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Development and Testing of the Europa Mission's Venturi Flow Meter

    NASA Technical Reports Server (NTRS)

    Diaz, C. E.; McKim, S. A.

    2017-01-01

    NASA's Marshall Space Flight Center (MSFC), in collaboration with NASA's Goddard Space Flight Center (GSFC), Fox Valve Development Corp. and Oxford Lasers, is developing a set of venturi flow meters for use on the Europa Mission's propulsion subsystem. The requirement for the venturi flow meters' throat diameters is approximately 0.040". An early risk reduction activity conducted by MSFC revealed that a venturi flow meter produced by FOX with a throat diameter near 0.040" had much higher pressure loss than venturi flow meters with larger throat diameters and venturis of similar throat diameter size but with no pressure taps (i.e. venturis with a throat length to diameter ratio of zero). In response, a series of venturi flow meters was fabricated and flow tested to gain insight into pressure recovery as it is affected by pressure port diameter, throat length and diffuser angle in an effort to improve the performance of a venturi flow meter. This presentation provides a summary of the venturi flow meter development activity including: a description of the test's objectives, a detailed description of each venturi configuration, a description of the manufacturing processes of the venturis, and observations from the test data. A summary of the current development activities will also be given, as well as the current development path forward. Ultimately, the knowledge gained through the fabrication and testing of these venturis provides guidance to design a flight venturi flow meters with pressure recoveries that is acceptable for the Europa flight application.

  8. Reactor pressure vessel nozzle

    DOEpatents

    Challberg, R.C.; Upton, H.A.

    1994-10-04

    A nozzle for joining a pool of water to a nuclear reactor pressure vessel includes a tubular body having a proximal end joinable to the pressure vessel and a distal end joinable in flow communication with the pool. The body includes a flow passage therethrough having in serial flow communication a first port at the distal end, a throat spaced axially from the first port, a conical channel extending axially from the throat, and a second port at the proximal end which is joinable in flow communication with the pressure vessel. The inner diameter of the flow passage decreases from the first port to the throat and then increases along the conical channel to the second port. In this way, the conical channel acts as a diverging channel or diffuser in the forward flow direction from the first port to the second port for recovering pressure due to the flow restriction provided by the throat. In the backflow direction from the second port to the first port, the conical channel is a converging channel and with the abrupt increase in flow area from the throat to the first port collectively increase resistance to flow therethrough. 2 figs.

  9. Study into the correlation of dominant pore throat size and SIP relaxation frequency

    NASA Astrophysics Data System (ADS)

    Kruschwitz, Sabine; Prinz, Carsten; Zimathies, Annett

    2016-12-01

    There is currently a debate within the SIP community about the characteristic textural length scale controlling relaxation time of consolidated porous media. One idea is that the relaxation time is dominated by the pore throat size distribution or more specifically the modal pore throat size as determined in mercury intrusion capillary pressure tests. Recently new studies on inverting pore size distributions from SIP data were published implying that the relaxation mechanisms and controlling length scale are well understood. In contrast new analytical model studies based on the Marshall-Madden membrane polarization theory suggested that two relaxation processes might compete: the one along the short narrow pore (the throat) with one across the wider pore in case the narrow pores become relatively long. This paper presents a first systematically focused study into the relationship of pore throat sizes and SIP relaxation times. The generality of predicted trends is investigated across a wide range of materials differing considerably in chemical composition, specific surface and pore space characteristics. Three different groups of relaxation behaviors can be clearly distinguished. The different behaviors are related to clay content and type, carbonate content, size of the grains and the wide pores in the samples.

  10. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300... chair and table, drawers for equipment, suction and blowing apparatus, and receptacles for connection of...

  11. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300... chair and table, drawers for equipment, suction and blowing apparatus, and receptacles for connection of...

  12. Jewelry cleaners

    MedlinePlus

    ... swelling (may also cause breathing difficulty) EYES, EARS, NOSE, AND THROAT Severe pain in the throat Severe pain or burning in the nose, eyes, ears, lips, or tongue Vision loss GASTROINTESTINAL SYSTEM ... pain (severe) Bloody stools Burns and possible holes of ...

  13. Side Effects: Mouth and Throat Problems

    Cancer.gov

    Cancer treatments may cause dental, mouth, and throat side effects such as changes in taste (dysgeusia), dry mouth (xerostomia), infections, mouth sores, pain or swelling in your mouth (oral mucositis), sensitivity to foods, and swallowing problems.

  14. Pediatric Obesity and Ear, Nose, and Throat Disorders

    MedlinePlus

    ... Marketplace Find an ENT Doctor Near You Pediatric Obesity and Ear, Nose, and Throat Disorders Pediatric Obesity ... self-esteem, and isolation from their peers. Pediatric obesity and otolaryngic problems Otolaryngologists, or ear, nose, and ...

  15. The impact of incubating the throat culture for 72 h on the diagnosis of group A beta-hemolytic streptococci.

    PubMed

    Kocoglu, Esra; Karabay, Oguz; Yilmaz, Fahrettin; Ekerbicer, Hasan

    2006-09-01

    The accurate detection and treatment of group A beta-hemolytic streptococcal pharyngitis is important to prevent the potential sequels. Throat culture remains the gold standard for the diagnosis of streptococcal pharyngitis. Many authors recommended 48 h incubation time for the isolation of group A Streptococcus (GAS). In this study the diagnostic efficacy of prolonging the incubation time of throat cultures to 72 h for isolation of GAS was researched. Throat swab specimens were inoculated to 5% sheep blood agar plate and incubated at 37 degrees C, and evaluated at the 24th hour. GAS negative plates were incubated again for another 24h and read at the 48th hour. Negative plates at 48 h were incubated again, read at the 72nd hour, and positive results of all measurements were evaluated. A total of 367 cultures were examined. At the 24th hour evaluation 34 (9.3%) cultures were positive for GAS. Evaluation of 333 cultures that were found to be negative in the first 24th hour evaluation revealed 44 (13.6%) positive cultures at 48th hour evaluation. Out of 289 cultures that were negative during the 48th hour evaluation, an additional 13 (4.7%) cultures were found to be positive during the 72nd hour evaluation. The agreement between 24th-48th and 24th and 72nd were both moderate (kappa 0.54 and 0. 46, respectively), and between 48th and 72nd hour was very good (kappa: 0.90). Throat cultures that are negative for GAS at 24h should be incubated for second day. We conclude that, to confirm the throat cultures GAS negative, results of throat cultures need to be incubated for 72 h, since 72nd hour evaluations revealed additional 5% positive results.

  16. Island biology and morphological divergence of the Skyros wall lizard Podarcis gaigeae: a combined role for local selection and genetic drift on color morph frequency divergence?

    PubMed Central

    2010-01-01

    Background Patterns of spatial variation in discrete phenotypic traits can be used to draw inferences about the adaptive significance of traits and evolutionary processes, especially when compared to patterns of neutral genetic variation. Population divergence in adaptive traits such as color morphs can be influenced by both local ecology and stochastic factors such as genetic drift or founder events. Here, we use quantitative color measurements of males and females of Skyros wall lizard, Podarcis gaigeae, to demonstrate that this species is polymorphic with respect to throat color, and the morphs form discrete phenotypic clusters with limited overlap between categories. We use divergence in throat color morph frequencies and compare that to neutral genetic variation to infer the evolutionary processes acting on islet- and mainland populations. Results Geographically close islet- and mainland populations of the Skyros wall lizard exhibit strong divergence in throat color morph frequencies. Population variation in throat color morph frequencies between islets was higher than that between mainland populations, and the effective population sizes on the islets were small (Ne:s < 100). Population divergence (FST) for throat color morph frequencies fell within the neutral FST-distribution estimated from microsatellite markers, and genetic drift could thus not be rejected as an explanation for the pattern. Moreover, for both comparisons among mainland-mainland population pairs and between mainland-islet population pairs, morph frequency divergence was significantly correlated with neutral divergence, further pointing to some role for genetic drift in divergence also at the phenotypic level of throat color morphs. Conclusions Genetic drift could not be rejected as an explanation for the pattern of population divergence in morph frequencies. In spite of an expected stabilising selection, throat color frequencies diverged in the islet populations. These results suggest that there is an interaction between selection and genetic drift causing divergence even at a phenotypic level in these small, subdivided populations. PMID:20813033

  17. Sore Throat: Symptoms and Causes

    MedlinePlus

    ... of the mouth, throat and voice box. Allergies. Seasonal allergies or ongoing allergic reactions to dust, molds ... HIV, diabetes, treatment with steroids or chemotherapy drugs, stress, fatigue, and ... when soap and water aren't available. Avoid touching public phones or ...

  18. Internal performance characteristics of vectored axisymmetric ejector nozzles

    NASA Technical Reports Server (NTRS)

    Lamb, Milton

    1993-01-01

    A series of vectoring axisymmetric ejector nozzles were designed and experimentally tested for internal performance and pumping characteristics at NASA-Langley Research Center. These ejector nozzles used convergent-divergent nozzles as the primary nozzles. The model geometric variables investigated were primary nozzle throat area, primary nozzle expansion ratio, effective ejector expansion ratio (ratio of shroud exit area to primary nozzle throat area), ratio of minimum ejector area to primary nozzle throat area, ratio of ejector upper slot height to lower slot height (measured on the vertical centerline), and thrust vector angle. The primary nozzle pressure ratio was varied from 2.0 to 10.0 depending upon primary nozzle throat area. The corrected ejector-to-primary nozzle weight-flow ratio was varied from 0 (no secondary flow) to approximately 0.21 (21 percent of primary weight-flow rate) depending on ejector nozzle configuration. In addition to the internal performance and pumping characteristics, static pressures were obtained on the shroud walls.

  19. Sore throat: Is it such a big deal anymore?

    PubMed

    Herath, Verangi C K; Carapetis, Jonathan

    2015-06-01

    Sore throat remains a common disease of childhood, and a major cost and cause for antibiotic prescriptions. The management of sore throat remains controversial in affluent countries with various guidelines available and overall poor adherence to those guidelines. Group A streptococcus is the commonest bacterial cause with important sequelae including acute rheumatic fever (ARF). The driver for diagnosis and treatment is still questionable. In most affluent populations it is difficult to justify antibiotic treatment on the basis of preventing ARF, whereas this remains the major driver for sore throat management in populations at higher risk of ARF. Reduction in severity and duration of symptoms may be a reasonable basis to consider antibiotic treatment, and thus accurate diagnosis of GAS pharyngitis, particularly in those with more severe symptoms. The potential role of rapid tests in diagnosis appears to be increasing. Copyright © 2015 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  20. Improvement on Main/backup Controller Switching Device of the Nozzle Throat Area Control System for a Turbofan Aero Engine

    NASA Astrophysics Data System (ADS)

    Li, Jie; Duan, Minghu; Yan, Maode; Li, Gang; Li, Xiaohui

    2014-06-01

    A full authority digital electronic controller (FADEC) equipped with a full authority hydro-mechanical backup controller (FAHMBC) is adopted as the nozzle throat area control system (NTACS) of a turbofan aero engine. In order to ensure the switching reliability of the main/backup controller, the nozzle throat area control switching valve was improved from three-way convex desktop slide valve to six-way convex desktop slide valve. Simulation results show that, if malfunctions of FAEDC occur and abnormal signals are outputted from FADEC, NTACS will be seriously influenced by the main/backup controller switching in several working states, while NTACS will not be influenced by using the improved nozzle throat area control switching valve, thus the controller switching process will become safer and smoother and the working reliability of this turbofan aero engine is improved by the controller switching device improvement.

  1. Diagnosis of group A streptococcal infections directly from throat secretions.

    PubMed Central

    Edwards, E A; Phillips, I A; Suiter, W C

    1982-01-01

    The diagnosis of group A streptococcal disease still relies on isolation of group A streptococcal strains on sheep blood agar followed by presumptive identification based on bacitracin sensitivity or the results of the more precise serogrouping methods such as the Lancefield precipitin test. A technique that would permit rapid identification of streptococcal infections directly from throat secretions would allow immediate appropriate antimicrobial therapy for the management of streptococcal infections to be started. We have been able to identify soluble group A antigen directly from throat secretions by using a latex agglutination test. In a clinical trial in which latex (Streptex group A) and conventional culturing techniques were used, 53 throat secretion cultures were tested: 26 were positive by both procedures, 5 were positive by culture only, 3 were positive by the latex agglutination test only, and 19 were negative by both tests. Images PMID:7042747

  2. International migration patterns of Red-throated Loons (Gavia stellata) from four breeding populations in Alaska

    USGS Publications Warehouse

    McCloskey, Sarah E.; Uher-Koch, Brian D.; Schmutz, Joel A.; Fondell, Thomas F.

    2018-01-01

    Identifying post-breeding migration and wintering distributions of migratory birds is important for understanding factors that may drive population dynamics. Red-throated Loons (Gavia stellata) are widely distributed across Alaska and currently have varying population trends, including some populations with recent periods of decline. To investigate population differentiation and the location of migration pathways and wintering areas, which may inform population trend patterns, we used satellite transmitters (n = 32) to describe migration patterns of four geographically separate breeding populations of Red-throated Loons in Alaska. On average (± SD) Red-throated Loons underwent long (6,288 ± 1,825 km) fall and spring migrations predominantly along coastlines. The most northern population (Arctic Coastal Plain) migrated westward to East Asia and traveled approximately 2,000 km farther to wintering sites than the three more southerly populations (Seward Peninsula, Yukon-Kuskokwim Delta, and Copper River Delta) which migrated south along the Pacific coast of North America. These migration paths are consistent with the hypothesis that Red-throated Loons from the Arctic Coastal Plain are exposed to contaminants in East Asia. The three more southerly breeding populations demonstrated a chain migration pattern in which the more northerly breeding populations generally wintered in more northerly latitudes. Collectively, the migration paths observed in this study demonstrate that some geographically distinct breeding populations overlap in wintering distribution while others use highly different wintering areas. Red-throated Loon population trends in Alaska may therefore be driven by a wide range of effects throughout the annual cycle.

  3. Rapid PCR detection of group A Streptococcus from flocked throat swabs: a retrospective clinical study.

    PubMed

    Slinger, Robert; Goldfarb, David; Rajakumar, Derek; Moldovan, Ioana; Barrowman, Nicholas; Tam, Ronald; Chan, Francis

    2011-09-02

    Rapid diagnosis of GAS pharyngitis may improve patient care by ensuring that patients with GAS pharyngitis are treated quickly and also avoiding unnecessary use of antibiotics in those without GAS infection. Very few molecular methods for detection of GAS in clinical throat swab specimens have been described. We performed a study of a laboratory-developed internally-controlled rapid Group A streptococcus (GAS) PCR assay using flocked swab throat specimens. We compared the GAS PCR assay to GAS culture results using a collection of archived throat swab samples obtained during a study comparing the performance of conventional and flocked throat swabs. The sensitivity of the GAS PCR assay as compared to the reference standard was 96.0% (95% CI 90.1% to 98.4%), specificity 98.6% (95% CI 95.8% to 99.5%), positive predictive value (PPV) 96.9% (95% CI 91.4% to 99.0%) and negative predictive value (NPV) of 98.1% (95% CI 95.2% to 99.2%). For conventional swab cultures, sensitivity was 96.0% (95% CI 90.1% to 98.4%), specificity 100% (95% CI 98.2% to 100%), PPV 100%, (95% CI 96.1% to 100%) and NPV 98.1% (95% CI 95.2% to 99.3%) In this retrospective study, the GAS PCR assay appeared to perform as well as conventional throat swab culture, the current standard of practice. Since the GAS PCR assay, including DNA extraction, can be performed in approximately 1 hour, prospective studies of this assay are warranted to evaluate the clinical impact of the assay on management of patients with pharyngitis.

  4. Management of patients with sore throats in relation to guidelines: an interview study in Sweden.

    PubMed

    Hedin, Katarina; Strandberg, Eva Lena; Gröndal, Hedvig; Brorsson, Annika; Thulesius, Hans; André, Malin

    2014-12-01

    To explore how a group of Swedish general practitioners (GPs) manage patients with a sore throat in relation to current guidelines as expressed in interviews. Qualitative content analysis was used to analyse semi-structured interviews. Swedish primary care. A strategic sample of 25 GPs. Perceived management of sore throat patients. It was found that nine of the interviewed GPs were adherent to current guidelines for sore throat and 16 were non-adherent. The two groups differed in terms of guideline knowledge, which was shared within the team for adherent GPs while idiosyncratic knowledge dominated for the non-adherent GPs. Adherent GPs had no or low concerns for bacterial infections and differential diagnosis whilst non-adherent GPs believed that in patients with a sore throat any bacterial infection should be identified and treated with antibiotics. Patient history and examination was mainly targeted by adherent GPs whilst for non-adherent GPs it was often redundant. Non-adherent GPs reported problems getting patients to abstain from antibiotics, whilst no such problems were reported in adherent GPs. This interview study of sore throat management in a strategically sampled group of Swedish GPs showed that while two-thirds were non-adherent and had a liberal attitude to antibiotics one-third were guideline adherent with a restricted view on antibiotics. Non-adherent GPs revealed significant knowledge gaps. Adherent GPs had discussed guidelines within the primary care team while non-adherent GPs had not. Guideline implementation thus seemed to be promoted by knowledge shared in team discussions.

  5. Efficacy of flurbiprofen 8.75 mg delivered as a spray or lozenge in patients with sore throat due to upper respiratory tract infection: a randomized, non-inferiority trial in the Russian Federation

    PubMed Central

    Radkova, Eugenia; Burova, Natalia; Bychkova, Valeria; DeVito, Robert

    2017-01-01

    Objective To assess the efficacy of flurbiprofen 8.75 mg delivered as a spray or lozenge in patients with sore throat due to upper respiratory tract infection (URTI). Materials and methods This multicenter, double-blind, double-dummy, non-inferiority study randomized 440 adults with recent-onset, moderate-to-severe sore throat due to URTI to a single dose of either flurbiprofen 8.75 mg spray (n=218) or flurbiprofen 8.75 mg lozenge (n=222). The presence or absence of beta-hemolytic streptococci (A or C) was confirmed by culture tests (throat swab). The primary efficacy end point was the difference from baseline to 2 hours post-dose in sore throat pain intensity scale (STPIS pain intensity difference [PID] 2h), a validated 100 mm visual analog scale (from 0=“no pain” to 100=“severe pain”), with a non-inferiority margin of −6 mm. Secondary end points included STPIS PID at 1 hour (STPIS PID 1h) and over 2 hours (STPIS sum of sore throat pain intensity differences [SPID]0–2h) and ratings of patient satisfaction and investigator assessment of drug efficacy at 2 hours. Safety (adverse events [AEs]) was also assessed. Results Reductions in sore throat pain intensity at 2 hours (STPIS PID 2h) were similar for spray (least square mean −40.51) and lozenge (−40.10) (difference: 0.41, 95% confidence interval [95% CI] −3.20, 4.01), with non-inferiority demonstrated. Subgroup analyses showed similar efficacy (STPIS PID 2h) for patients testing positive or negative for Strep A or C. There was no significant difference between spray and lozenge in STPIS PID 1h or STPIS SPID0–2h, and patient satisfaction and investigators’ assessment of efficacy at 2 hours were similar for both groups. There were no significant differences in AEs between the two groups, with 17 drug-related events across both groups, all being mild and none being serious. Conclusion Both formulations demonstrated comparable efficacy and safety profiles and provide patients with two different treatment formats to choose from for effective symptomatic relief of sore throat, depending on their preference. PMID:28740426

  6. Efficacy of flurbiprofen 8.75 mg delivered as a spray or lozenge in patients with sore throat due to upper respiratory tract infection: a randomized, non-inferiority trial in the Russian Federation.

    PubMed

    Radkova, Eugenia; Burova, Natalia; Bychkova, Valeria; DeVito, Robert

    2017-01-01

    To assess the efficacy of flurbiprofen 8.75 mg delivered as a spray or lozenge in patients with sore throat due to upper respiratory tract infection (URTI). This multicenter, double-blind, double-dummy, non-inferiority study randomized 440 adults with recent-onset, moderate-to-severe sore throat due to URTI to a single dose of either flurbiprofen 8.75 mg spray (n=218) or flurbiprofen 8.75 mg lozenge (n=222). The presence or absence of beta-hemolytic streptococci (A or C) was confirmed by culture tests (throat swab). The primary efficacy end point was the difference from baseline to 2 hours post-dose in sore throat pain intensity scale (STPIS pain intensity difference [PID] 2h), a validated 100 mm visual analog scale (from 0="no pain" to 100="severe pain"), with a non-inferiority margin of -6 mm. Secondary end points included STPIS PID at 1 hour (STPIS PID 1h) and over 2 hours (STPIS sum of sore throat pain intensity differences [SPID] 0-2h ) and ratings of patient satisfaction and investigator assessment of drug efficacy at 2 hours. Safety (adverse events [AEs]) was also assessed. Reductions in sore throat pain intensity at 2 hours (STPIS PID 2h) were similar for spray (least square mean -40.51) and lozenge (-40.10) (difference: 0.41, 95% confidence interval [95% CI] -3.20, 4.01), with non-inferiority demonstrated. Subgroup analyses showed similar efficacy (STPIS PID 2h) for patients testing positive or negative for Strep A or C. There was no significant difference between spray and lozenge in STPIS PID 1h or STPIS SPID 0-2h , and patient satisfaction and investigators' assessment of efficacy at 2 hours were similar for both groups. There were no significant differences in AEs between the two groups, with 17 drug-related events across both groups, all being mild and none being serious. Both formulations demonstrated comparable efficacy and safety profiles and provide patients with two different treatment formats to choose from for effective symptomatic relief of sore throat, depending on their preference.

  7. Vocal Cord Paralysis

    MedlinePlus

    ... paralysis. Known causes may include: Injury to the vocal cord during surgery. Surgery on or near your neck or upper ... Factors that may increase your risk of developing vocal cord paralysis include: Undergoing throat or chest surgery. People who need surgery on their thyroid, throat ...

  8. Static internal performance of a two-dimensional convergent-divergent nozzle with thrust vectoring

    NASA Technical Reports Server (NTRS)

    Bare, E. Ann; Reubush, David E.

    1987-01-01

    A parametric investigation of the static internal performance of multifunction two-dimensional convergent-divergent nozzles has been made in the static test facility of the Langley 16-Foot Transonic Tunnel. All nozzles had a constant throat area and aspect ratio. The effects of upper and lower flap angles, divergent flap length, throat approach angle, sidewall containment, and throat geometry were determined. All nozzles were tested at a thrust vector angle that varied from 5.60 tp 23.00 deg. The nozzle pressure ratio was varied up to 10 for all configurations.

  9. Towards multi-field D-brane inflation in a warped throat

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

    Chen, Heng-Yu; Gong, Jinn-Ouk; Koyama, Kazuya

    2010-11-01

    We study the inflationary dynamics in a model of slow-roll inflation in warped throat. Inflation is realized by the motion of a D-brane along the radial direction of the throat, and at later stages instabilities develop in the angular directions. We closely investigate both the single field potential relevant for the slow-roll phase, and the full multi-field one including the angular modes which becomes important at later stages. We study the main features of the instability process, discussing its possible consequences and identifying the vacua towards which the angular modes are driven.

  10. Impact of droplet evaporation rate on resulting in vitro performance parameters of pressurized metered dose inhalers.

    PubMed

    Sheth, Poonam; Grimes, Matthew R; Stein, Stephen W; Myrdal, Paul B

    2017-08-07

    Pressurized metered dose inhalers (pMDIs) are widely used for the treatment of pulmonary diseases. The overall efficiency of pMDI drug delivery may be defined by in vitro parameters such as the amount of drug that deposits on the model throat and the proportion of the emitted dose that has particles that are sufficiently small to deposit in the lung (i.e., fine particle fraction, FPF). The study presented examines product performance of ten solution pMDI formulations containing a variety of cosolvents with diverse chemical characteristics by cascade impaction with three inlets (USP induction port, Alberta Idealized Throat, and a large volume chamber). Through the data generated in support of this study, it was demonstrated that throat deposition, cascade impactor deposition, FPF, and mass median aerodynamic diameter of solution pMDIs depend on the concentration and vapor pressure of the cosolvent, and the selection of model throat. Theoretical droplet lifetimes were calculated for each formulation using a discrete two-stage evaporation process model and it was determined that the droplet lifetime is highly correlated to throat deposition and FPF indicating that evaporation kinetics significantly influences pMDI drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Antiproliferative Activity of Triterpene Glycoside Nutrient from Monk Fruit in Colorectal Cancer and Throat Cancer.

    PubMed

    Liu, Can; Dai, Longhai; Liu, Yueping; Rong, Long; Dou, Dequan; Sun, Yuanxia; Ma, Lanqing

    2016-06-13

    Colorectal cancer and throat cancer are the world's most prevalent neoplastic diseases, and a serious threat to human health. Plant triterpene glycosides have demonstrated antitumor activity. In this study, we investigated potential anticancer effects of mogroside IVe, a triterpenoid glycoside from monk fruit, using in vitro and in vivo models of colorectal and laryngeal cancer. The effects of mogroside IVe on the proliferation of colorectal cancer HT29 cells and throat cancer Hep-2 cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the expression levels of p53, phosphorylated ERK1/2, and MMP-9 were analyzed by western blotting and immunohistochemistry. The results indicated that mogroside IVe inhibited, in a dose-dependent manner, the proliferation of HT29 and Hep-2 cells in culture and in xenografted mice, which was accompanied by the upregulation of tumor suppressor p53, and downregulation of matrix metallopeptidase 9 (MMP-9) and phosphorylated extracellular signal-regulated kinases (ERK)1/2. This study revealed the suppressive activity of mogroside IVe towards colorectal and throat cancers and identified the underlying mechanisms, suggesting that mogroside IVe may be potentially used as a biologically-active phytochemical supplement for treating colorectal and throat cancers.

  12. Dual-throat thruster thermal model

    NASA Technical Reports Server (NTRS)

    Ewen, R. L.; Obrien, C. J.; Matthews, L. W.

    1986-01-01

    The dual-throat engine is one of the dual nozzle engine concepts studied for advanced space transportation applications. It provides a thrust change and an in-flight area ratio change through the use of two concentric combustors with their throats arranged in series. Test results are presented for a dual throat thruster burning gaseous oxygen and hydrogen at primary (inner) chamber pressures from 380 to 680 psia. Heat flux profiles were obtained from calorimetric cooling channels in the inner nozzle, outer or secondary chamber and the tip of the inner nozzle. Data were obtained for two nozzle spacings over a chamber pressure ratio (secondary/primary) range of 0.45 to 0.83 with both chambers firing (Mode I). Fluxes near the end of the inner nozzle were significantly higher than in Mode II when only the inner chamber was fired, due to the flow separation and recirculation caused by the back pressure imposed by the secondary chamber. As the pressure ratio increased, these heat fluxes increased and the region of high heat flux relative to Mode II extended farther upstream. The use of the gaseous hydrogen bleed flow in the secondary chamber to control heat fluxes in the primary plume attachment region was investigated in Mode II testing. A thermal model of a dual throat thruster was developed and upgraded using the experimental data.

  13. Egg flotation estimates nest age for Pacific and Red-throated Loons

    USGS Publications Warehouse

    Rizzolo, Daniel; Schmutz, Joel A.

    2007-01-01

    We used Pacific Loon (Gavia pacifica) and Red-throated Loon (G. stellata) nests with known ages to gauge the efficacy of egg flotation for determining nest age in coastal Alaska. Egg flotation accurately estimated nest age for both species; the mean ± 1SD difference between known age and age determined with egg flotation was - 0.05 ± 2.00 d and -0.02 ± 1.63 d for Pacific and Red-throated Loons, respectively. Day of nest initiation did not influence the relationship between known nest age and nest age estimated with egg flotation, indicating incubation period was not shortened in nests initiated later in the season. Additionally, we found no difference in the ability of egg flotation to estimate nest age between two widely dispersed study sites for Pacific Loons, and only a small difference between two of three widely dispersed study sites for Red-throated Loons. Thus, our described relationships between egg flotation categories and nest age should be broadly applicable for these holarctic species. We conclude that for Pacific and Red-throated Loons, egg flotation is a useful technique for determining nest age in the field to better monitor nest fate, and to quantify nest age effects on nest daily survival rate.

  14. Empirical validation of guidelines for the management of pharyngitis in children and adults.

    PubMed

    McIsaac, Warren J; Kellner, James D; Aufricht, Peggy; Vanjaka, Anita; Low, Donald E

    2004-04-07

    Recent guidelines for management of pharyngitis vary in their recommendations concerning empirical antibiotic treatment and the need for laboratory confirmation of group A streptococcus (GAS). To assess the impact of guideline recommendations and alternative approaches on identification and treatment of GAS pharyngitis in children and adults. Throat cultures and rapid antigen tests were performed on 787 children and adults aged 3 to 69 years with acute sore throat attending a family medicine clinic in Calgary, Alberta, from September 1999 to August 2002. Recommendations from 2 guidelines (those of the Infectious Diseases Society of America and of the American College of Physicians-American Society of Internal Medicine/American Academy of Family Physicians/US Centers for Disease Control and Prevention) were compared with rapid testing alone, a clinical prediction rule (ie, the modified Centor score), and a criterion standard of treatment for positive throat culture results only. Sensitivity and specificity of each strategy for identifying GAS pharyngitis, total antibiotics recommended, and unnecessary antibiotic prescriptions. In children, sensitivity for streptococcal infection ranged from 85.8% (133/155; 95% confidence interval [CI], 79.3%-90.0%) for rapid testing to 100% for culturing all. In adults, sensitivity ranged from 76.7% (56/73; 95% CI, 65.4%-85.8%) for rapid testing without culture confirmation of negative results to 100% for culturing all. In children, specificity ranged from 90.3% (270/299; 95% CI, 86.4%-93.4%) for use of modified Centor score and throat culture to 100% for culturing all. In adults, specificity ranged from 43.8% (114/260; 95% CI, 37.7%-50.1%) for empirical treatment based on a modified Centor score of 3 or 4 to 100% for culturing all. Total antibiotic prescriptions were lowest with rapid testing (24.7% [194/787]; 95% CI, 21.7%-27.8%) and highest with empirical treatment of high-risk adults (45.7% [360/787]; 95% CI, 42.2%-49.3%), due to a high rate of unnecessary prescriptions in adults (43.8% [146/333]; 95% CI, 38.4%-49.4%). Guideline recommendations for the selective use of throat cultures but antibiotic treatment based only on positive rapid test or throat culture results can reduce unnecessary use of antibiotics for treatment of pharyngitis. However, empirical treatment of adults having a Centor score of 3 or 4 is associated with a high rate of unnecessary antibiotic use. In children, strategies incorporating throat culture or throat culture confirmation of negative rapid antigen test results are highly sensitive and specific. Throat culture of all adults or those selected on the basis of a clinical prediction rule had the highest sensitivity and specificity.

  15. Embedded Si/Graphene Composite Fabricated by Magnesium-Thermal Reduction as Anode Material for Lithium-Ion Batteries

    NASA Astrophysics Data System (ADS)

    Zhu, Jiangliu; Ren, Yurong; Yang, Bo; Chen, Wenkai; Ding, Jianning

    2017-12-01

    Embedded Si/graphene composite was fabricated by a novel method, which was in situ generated SiO2 particles on graphene sheets followed by magnesium-thermal reduction. The tetraethyl orthosilicate (TEOS) and flake graphite was used as original materials. On the one hand, the unique structure of as-obtained composite accommodated the large volume change to some extent. Simultaneously, it enhanced electronic conductivity during Li-ion insertion/extraction. The MR-Si/G composite is used as the anode material for lithium ion batteries, which shows high reversible capacity and ascendant cycling stability reach to 950 mAh·g-1 at a current density of 50 mA·g-1 after 60 cycles. These may be conducive to the further advancement of Si-based composite anode design.

  16. Physical interpretation and application of principles of ultrasonic nondestructive evaluation of high-performance materials

    NASA Technical Reports Server (NTRS)

    Miller, James G.

    1990-01-01

    An ultrasonic measurement system employed in the experimental interrogation of the anisotropic properties (through the measurement of the elastic stiffness constants) of the uniaxial graphite-epoxy composites is presented. The continuing effort for the development of improved visualization techniques for physical parameters is discussed. The background is set for the understanding and visualization of the relationship between the phase and energy/group velocity for propagation in high-performance anisotropic materials by investigating the general requirements imposed by the classical wave equation. The consequences are considered when the physical parameters of the anisotropic material are inserted into the classical wave equation by a linear elastic model. The relationship is described between the phase velocity and the energy/group velocity three dimensional surfaces through graphical techniques.

  17. Mononucleosis

    MedlinePlus

    ... foods and drink lots of water to prevent dehydration. If you have a sore throat, gargle saltwater, drink tea with honey, or suck on hard candy or ice pops. You can get some nutrition and soothe your throat with cold fruit smoothies or low-fat shakes. When you start ...

  18. Which is the best method to trace group A streptococci in sore throat patients: culture or GAS antigen test?

    PubMed

    Lindbaek, Morten; Høiby, Ernst Arne; Lermark, Gro; Steinsholt, Inger Marie; Hjortdahl, Per

    2004-12-01

    To compare an antigen detection test (GAS antigen test) with the results from combinations of two various bacteriological test media in general practice patients with sore throat. Furthermore to assess the diagnostic properties of the chosen GAS antigen test and to compare semi-quantitative results of this test with the bacterial load found in the throat culture. Two Norwegian general practices in Stokke and Kongsberg communities. 306 patients with sore throat lasting less than 7 days; 244 were adults, 62 were children under 10 years old, mean age 23.9 years (SD 15.0), 40% were men. Results from GAS antigen test, and distribution of bacteriological findings in throat cultures, compared with the results of our GAS antigen test; semi-quantitative results of the GAS antigen test compared with the bacterial load by culture. In the primary culture 110 patients harboured group A streptococci (GAS) infection, while the second culture identified another 17, giving a total of 127 patients. Some 33 patients harboured large-colony groups C and G. The GAS antigen test used had a sensitivity of 97% and specificity of 95% regarding GAS when compared with the two cultures. We found a significant correlation between the bacterial loads by culture and the semi-quantitative results of the GAS antigen test. By using a second, different set of bacteriological media, we identified an additional 17 patients with GAS infections. This raises the question of validity of frequently used reference standards in studies related to streptococcal infections. Compared with the combined results of the two throat cultures, the GAS antigen test used showed high sensitivity and specificity. Semi-quantitative evaluations of the rapid immunological test may also be of clinical value.

  19. NORMAL FLORA OF THE NOSE, THROAT, AND LOWER INTESTINE OF DOGS

    PubMed Central

    Clapper, W. E.; Meade, G. H.

    1963-01-01

    Clapper, W. E. (The Lovelace Foundation for Medical Education and Research, Albuquerque, N.M.) and G. H. Meade. Normal flora of the nose, throat, and lower intestine of dogs. J. Bacteriol. 85:643–648. 1963.—An attempt was made to isolate and identify the complete normal flora of the rectum, nose, and throat of beagles. For primary isolation, 12 different kinds of media were used. Incubation of blood agar plates and slants anaerobically, and of thioglycolate broth aerobically, allowed the growth of obligate anaerobes. From the rectal specimens, 20 species of bacteria and 10 species of fungi were isolated and identified. The organisms were similar to those found in the human intestine. Escherichia coli, Streptococcus mitis, enterococci, S. lactis, Bacillus species, and coliforms other than E. coli were most frequently encountered. The frequency of occurrence was approximately the same at both samplings in more commonly cultured bacteria. Pathogenic E. coli were isolated from nearly one-third of the first specimens. These were the only human pathogens observed. In the throat cultures, 29 species of bacteria and 2 species of yeasts were identified, and 27 species of bacteria were identified from the nasal cultures. S. mitis, Neisseria, and coagulase-negative Staphylococcus were most often isolated. The flora was similar to that found in human nose and throat cultures, except that more Haemophilus and pneumococcus and fewer coliforms are generally found in human throats. Organisms resembling human pathogens were group A streptococci and coagulase-positive staphylococci. These were isolated infrequently. It appears that this kind of examination would reveal any significant changes in normal flora that might be related to the health of the animal. PMID:14042944

  20. Survey of Spanish general practitioners' attitudes toward management of sore throat: an internet-based questionnaire study.

    PubMed

    Llor, Carl; Vilaseca, Isabel; Lehrer-Coriat, Eduardo; Boleda, Xavier; Cañada, José L; Moragas, Ana; Cots, Josep M

    2017-02-14

    The management of sore throat varies widely in Europe. The objective of this study was to gain insight into clinicians' perceptions on the current management of sore throat in Spain. Cross-sectional, internet-based questionnaire study answered from July to September 2013. General practitioners (GPs) affiliated with the two largest scientific societies of primary care were invited to participate in the study. Questions were asked about physician knowledge, the use of current national guidelines for sore throat management, and management in two clinical scenarios, depicting a young adult with sore throat and: 1. cough, coriza with or without fever, and 2. fever without cough and coriza. The questionnaire was completed by 1476 GPs (5%) and 12.7% declared using rapid antigen detection tests. Antibiotics were considered by 18.8% of the GPs in the first scenario and by 32% in the second scenario (p < 0.001). The antibiotics most commonly mentioned by GPs were amoxicillin and amoxicillin + clavulanate (52.7 and 31.2%, respectively) whereas penicillin V was only prescribed in 11.9% of the cases. The drugs most commonly considered in both scenarios were analgesics and anti-inflammatory drugs. Antitussives, decongestants and expectorants were more commonly prescribed in cases of suspected viral infection (p < 0.001). GPs have misconceptions as to the indications for using rapid antigen detection tests and prescribing drugs in the management of sore throat. These results suggest that guidelines are seldom followed since one in five GPs declared giving antibiotics for patients with a suspected viral infection and the use of second-choice antibiotics seems considerable.

  1. Detection of Japanese Encephalitis Virus RNA in Human Throat Samples in Laos - A Pilot study.

    PubMed

    Bharucha, Tehmina; Sengvilaipaseuth, Onanong; Seephonelee, Malee; Vongsouvath, Malavanh; Vongsouvath, Manivanh; Rattanavong, Sayaphet; Piorkowski, Géraldine; Lecuit, Marc; Gorman, Christopher; Pommier, Jean-David; Newton, Paul N; de Lamballerie, Xavier; Dubot-Pérès, Audrey

    2018-05-22

    Japanese encephalitis virus (JEV) is the most commonly identified cause of acute encephalitis syndrome (AES) in Asia. The WHO recommended test is anti-JEV IgM-antibody-capture-enzyme-linked-immunosorbent-assay (JEV MAC-ELISA). However, data suggest this has low positive predictive value, with false positives related to other Flavivirus infections and vaccination. JEV RT-PCR in cerebrospinal fluid (CSF) and/or serum is highly specific, but is rarely positive; 0-25% of patients that fulfil the WHO definition of JE (clinical Acute Encephalitis Syndrome (AES) and JEV MAC-ELISA positive). Testing other body fluids by JEV RT-qPCR may improve the diagnosis. As a pilot study thirty patients admitted to Mahosot Hospital 2014-2017, recruited to the South-East-Asia-Encephalitis study, were tested by JEV MAC-ELISA and two JEV real-time RT-PCR (RT-qPCR) assays (NS2A and NS3). Eleven (36.7%) were JEV MAC-ELISA positive. Available CSF and serum samples of these patients were JEV RT-qPCR negative but 2 (7%) had JEV RNA detected in their throat swabs. JEV RNA was confirmed by re-testing, and sequencing of RT-qPCR products. As the first apparent report of JEV RNA detection in human throat samples, the provides new perspectives on human JEV infection, potentially informing improving JEV detection. We suggest that testing patients' throat swabs for JEV RNA is performed, in combination with molecular and serological CSF and serum investigations, on a larger scale to investigate the epidemiology of the presence of JEV in human throats. Throat swabs are an easy and non-invasive tool that could be rolled out to a wider population to improve knowledge of JEV molecular epidemiology.

  2. Effects of sweet flavorings and nicotine on the appeal and sensory properties of e-cigarettes among young adult vapers: Application of a novel methodology.

    PubMed

    Goldenson, Nicholas I; Kirkpatrick, Matthew G; Barrington-Trimis, Jessica L; Pang, Raina D; McBeth, Julia F; Pentz, Mary Ann; Samet, Jonathan M; Leventhal, Adam M

    2016-11-01

    Product characteristics that impact e-cigarette appeal by altering the sensory experience of vaping need to be identified to formulate evidence-based regulatory policies. While products that contain sweet flavorings and produce a "throat hit" (i.e., desirable airway irritation putatively caused by nicotine) are anecdotally cited as desirable reasons for vaping among young adults, experimental evidence of their impact on user appeal is lacking. This experiment applied a novel laboratory protocol to assess whether: (1) sweet flavorings and nicotine affect e-cigarette appeal; (2) sweet flavorings increase perceived sweetness; (3) nicotine increases throat hit; and (4) perceived sweetness and throat hit are associated with appeal. Young adult vapers (N=20; age 19-34) self-administered 20 standardized doses of aerosolized e-cigarette solutions varied according to a 3 flavor (sweet [e.g., cotton candy] vs. non-sweet [e.g., tobacco-flavored] vs. flavorless)×2 nicotine (6mg/mL nicotine vs. 0mg/mL [placebo]) double-blind, cross-over design. Participants rated appeal (liking, willingness to use again and perceived monetary value), perceived sweetness and throat hit strength after each administration. Sweet-flavored (vs. non-sweet and flavorless) solutions produced greater appeal and perceived sweetness ratings. Nicotine produced greater throat hit ratings than placebo, but did not significantly increase appeal nor interact with flavor effects on appeal. Controlling for flavor and nicotine, perceived sweetness was positively associated with appeal ratings; throat hit was not positively associated with appeal. Further identification of compounds in e-cigarette solutions that enhance sensory perceptions of sweetness, appeal, and utilization of e-cigarettes are warranted to inform evidence-based regulatory policies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Incidence and clinical variables associated with streptococcal throat infections: a prospective diagnostic cohort study

    PubMed Central

    Little, Paul; Hobbs, FD Richard; Mant, David; McNulty, Cliodna AM; Mullee, Mark

    2012-01-01

    Background Management of pharyngitis is commonly based on features which are thought to be associated with Lancefield group A beta-haemolytic streptococci (GABHS) but it is debatable which features best predict GABHS. Non-group A strains share major virulence factors with group A, but it is unclear how commonly they present and whether their presentation differs. Aim To assess the incidence and clinical variables associated with streptococcal infections. Design and setting Prospective diagnostic cohort study in UK primary care. Method The presence of pathogenic streptococci from throat swabs was assessed among patients aged ≥5 years presenting with acute sore throat. Results Pathogenic streptococci were found in 204/597 patients (34%, 95% CI = 31 to 38%): 33% (68/204) were non-group A streptococci, mostly C (n = 29), G (n = 18) and B (n = 17); rarely D (n = 3) and Streptococcus pneumoniae (n = 1). Patients presented with similar features whether the streptococci were group A or non-group A. The features best predicting A, C or G beta-haemolytic streptococci were patient’s assessment of severity (odds ratio [OR] for a bad sore throat 3.31, 95% CI = 1.24 to 8.83); doctors’ assessment of severity (severely inflamed tonsils OR 2.28, 95% CI = 1.39 to 3.74); absence of a bad cough (OR 2.73, 95% CI = 1.56 to 4.76), absence of a coryza (OR 1.54, 95% CI = 0.99 to 2.41); and moderately bad or worse muscle aches (OR 2.20, 95% CI = 1.41 to 3.42). Conclusion Non-group A strains commonly cause streptococcal sore throats, and present with similar symptomatic clinical features to group A streptococci. The best features to predict streptococcal sore throat presenting in primary care deserve revisiting. PMID:23211183

  4. Incidence and clinical variables associated with streptococcal throat infections: a prospective diagnostic cohort study.

    PubMed

    Little, Paul; Hobbs, F D Richard; Mant, David; McNulty, Cliodna A M; Mullee, Mark

    2012-11-01

    Management of pharyngitis is commonly based on features which are thought to be associated with Lancefield group A beta-haemolytic streptococci (GABHS) but it is debatable which features best predict GABHS. Non-group A strains share major virulence factors with group A, but it is unclear how commonly they present and whether their presentation differs. To assess the incidence and clinical variables associated with streptococcal infections. Prospective diagnostic cohort study in UK primary care. The presence of pathogenic streptococci from throat swabs was assessed among patients aged ≥5 years presenting with acute sore throat. Pathogenic streptococci were found in 204/597 patients (34%, 95% CI = 31 to 38%): 33% (68/204) were non-group A streptococci, mostly C (n = 29), G (n = 18) and B (n = 17); rarely D (n = 3) and Streptococcus pneumoniae (n = 1). Patients presented with similar features whether the streptococci were group A or non-group A. The features best predicting A, C or G beta-haemolytic streptococci were patient's assessment of severity (odds ratio [OR] for a bad sore throat 3.31, 95% CI = 1.24 to 8.83); doctors' assessment of severity (severely inflamed tonsils OR 2.28, 95% CI = 1.39 to 3.74); absence of a bad cough (OR 2.73, 95% CI = 1.56 to 4.76), absence of a coryza (OR 1.54, 95% CI = 0.99 to 2.41); and moderately bad or worse muscle aches (OR 2.20, 95% CI = 1.41 to 3.42). Non-group A strains commonly cause streptococcal sore throats, and present with similar symptomatic clinical features to group A streptococci. The best features to predict streptococcal sore throat presenting in primary care deserve revisiting.

  5. Effects of Sweet Flavorings and Nicotine on the Appeal and Sensory Properties of e-Cigarettes Among Young Adult Vapers: Application of a Novel Methodology*

    PubMed Central

    Goldenson, Nicholas I.; Kirkpatrick, Matthew G.; Barrington-Trimis, Jessica L.; Pang, Raina D.; McBeth, Julia F.; Pentz, Mary Ann; Samet, Jonathan M.; Leventhal, Adam M.

    2016-01-01

    Introduction Product characteristics that impact e-cigarette appeal by altering the sensory experience of vaping need to be identified to formulate evidence-based regulatory policies. While products that contain sweet flavorings and produce a “throat hit” (i.e., desirable airway irritation putatively caused by nicotine) are anecdotally cited as desirable reasons for vaping among young adults, experimental evidence of their impact on user appeal is lacking. This experiment applied a novel laboratory protocol to assess whether: (1) sweet flavorings and nicotine affect e-cigarette appeal; (2) sweet flavorings increase perceived sweetness; (3) nicotine increases throat hit; and (4) perceived sweetness and throat hit are associated with appeal. Methods Young adult vapers (N=20; age 19–34) self-administered 20 standardized doses of aerosolized e-cigarette solutions varied according to a 3 flavor (sweet [e.g., cotton candy] vs. non-sweet [e.g., tobacco-flavored] vs. flavorless) × 2 nicotine (6 mg/mL nicotine vs. 0 mg/mL [placebo]) double-blind, cross-over design. Participants rated appeal (liking, willingness to use again and perceived monetary value), perceived sweetness and throat hit strength after each administration. Results Sweet-flavored (vs. non-sweet and flavorless) solutions produced greater appeal and perceived sweetness ratings. Nicotine produced greater throat hit ratings than placebo, but did not significantly increase appeal nor interact with flavor effects on appeal. Controlling for flavor and nicotine, perceived sweetness was positively associated with appeal ratings; throat hit was not positively associated with appeal. Conclusions Further identification of compounds in e-cigarette solutions that enhance sensory perceptions of sweetness, appeal, and utilization of e-cigarettes are warranted to inform evidence-based regulatory policies. PMID:27676583

  6. FLOW SIMULATION IN THE HUMAN UPPER RESPIRATORY TRACT

    EPA Science Inventory


    ABSTRACT

    Computer simulations of airflow patterns within the human upper respiratory tract (URT) are presented. The URT model includes airways of the head (nasal and oral), throat (pharyngeal and laryngeal), and lungs (trachea and main bronchi). The head and throat mor...

  7. Principles of ear nose and throat surgery for pregnant women.

    PubMed

    Baruah, Paramita; Jasraj, Kailey; Ahmad, Ijaz

    2017-04-02

    Management of the pregnant surgical patient is challenging. The surgical procedure is usually postponed until the postpartum period, although this may not be possible in emergency situations. This article highlights the optimal management of the pregnant woman requiring ear nose and throat surgery.

  8. Static investigation of several yaw vectoring concepts on nonaxisymmetric nozzles

    NASA Technical Reports Server (NTRS)

    Mason, M. L.; Berrier, B. L.

    1985-01-01

    A test has been conducted in the static test facility of the Langley 16-Foot Transonic Tunnel to determine the flow-turning capability and the effects on nozzle internal performance of several yaw vectoring concepts. Nonaxisymmetric convergent-divergent nozzles with throat areas simulating dry and afterburning power settings and single expansion ramp nozzles with a throat area simulating a dry power setting were modified for yaw thrust vectoring. Forward-thrust and pitch-vectored nozzle configurations were tested with each yaw vectoring concept. Four basic yaw vectoring concepts were investigated on the nonaxisymmetric convergent-divergent nozzles: (1) translating sidewall; (2) downstream (of throat) flaps; (3) upstream (of throat) port/flap; and (4) powered rudder. Selected combinations of the rudder with downstream flaps or upstream port/flap were also tested. A single yaw vectoring concept, post-exit flaps, was investigated on the single expansion ramp nozzles. All testing was conducted at static (no external flow) conditions and nozzle pressure ratios varied from 2.0 up to 10.0.

  9. A remote fuzzy multicriteria diagnosis of sore throat.

    PubMed

    Dalalah, Doraid; Magableh, Sami

    2008-09-01

    A sore throat (also known as pharyngitis or tonsillitis) is most commonly caused by a contagious viral infection (such as the flu, cold, or mononucleosis), although more serious throat infections can be caused by a bacterial infection (such as strep, mycoplasma, or Haemophilus). Bacterial sore throats respond well to antibiotics, whereas viral ones do not. However, strep throat remains a leading cause for physician visits, and researchers have long struggled to determine how best to treat it. The current practice guidelines offer different management options for adult patients presenting with a sore throat. Thus, when a physician treats a patient with acute pharyngitis, the clinical decision that usually needs to be made is whether the pharyngitis is attributable to group A streptococci. The key concern is the degree to which the clinical possibility of a group A streptococcal infection should affect clinician's decisions. To determine the best treatment of pharyngitis, we conducted a multicriteria decision analysis using fuzzy reasoning for remote health service delivery between a healthcare provider and patients. The approach can be adopted for interactive phone use or online system application. Five alternative treatment options were considered, particularly: (a) no test no Rx, (b) rapid strep, (c) culture, (d) rapid strep and culture, and (e) empiric Rx. Fuzzy reasoning is used to examine the signs/symptoms and their ratings. The study includes seven criteria factors that can be rated according to each alternative clinical treatment using linguistic statements. The model shows that no test no Rx is the best option for the cases of low prevalence of group A streptococcal infection. Two strategies--culture and treat if positive and rapid strep with culture of negative results--are equally preferable for patients with moderate prevalence likelihood. Rapid strep and culture of negative results is the best management strategy for patients with high population prevalence of group A streptococcal infection. In conclusion, the best clinical management of patients with sore throat depends on both the clinical probability of group A streptococcal infection and clinical judgments that incorporate the importance ratings of the individual patients as well as practice circumstances.

  10. The sensitivity and the specifity of rapid antigen test in streptococcal upper respiratory tract infections.

    PubMed

    Gurol, Yesim; Akan, Hulya; Izbirak, Guldal; Tekkanat, Zuhal Tazegun; Gunduz, Tehlile Silem; Hayran, Osman; Yilmaz, Gulden

    2010-06-01

    It is aimed to detect the sensitivity and specificity of rapid antigen detection of group A beta hemolytic streptococci from throat specimen compared with throat culture. The other goal of the study is to help in giving clinical decisions in upper respiratory tract infections according to the age group, by detection of sensitivity and positive predictive values of the rapid tests and throat cultures. Rapid antigen detection and throat culture results for group A beta hemolytic streptococci from outpatients attending to our university hospital between the first of November 2005 and 31st of December 2008 were evaluated retrospectively. Throat samples were obtained by swabs from the throat and transported in the Stuart medium and Quickvue Strep A [Quidel, San Diego, USA] cassette test was applied and for culture, specimen was inoculated on 5% blood sheep agar and identified according to bacitracin and trimethoprim-sulphametaxazole susceptibility from beta hemolytic colonies. During the dates between the first of November 2005 and 31st of December 2008, from 453 patients both rapid antigen detection and throat culture were evaluated. Rapid antigen detection sensitivity and specificity were found to be 64.6% and 96.79%, respectively. The positive predictive value was 80.95% whereas negative predictive value was 92.82%. Kappa index was 0.91. When the results were evaluated according to the age groups, the sensitivity and the positive predictive value of rapid antigen detection in children were 70%, 90.3% and in adults 59.4%, 70.4%. When bacterial infection is concerned to prevent unnecessary antibiotic use, rapid streptococcal antigen test (RSAT) is a reliable method to begin immediate treatment. To get the maximum sensitivity of RSAT, the specimen collection technique used and education of the health care workers is important. While giving clinical decision, it must be taken into consideration that the sensitivity and the positive predictive value of the RSAT is quite lower in adult age group than in pediatric age group. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  11. Method for producing dustless graphite spheres from waste graphite fines

    DOEpatents

    Pappano, Peter J [Oak Ridge, TN; Rogers, Michael R [Clinton, TN

    2012-05-08

    A method for producing graphite spheres from graphite fines by charging a quantity of spherical media into a rotatable cylindrical overcoater, charging a quantity of graphite fines into the overcoater thereby forming a first mixture of spherical media and graphite fines, rotating the overcoater at a speed such that the first mixture climbs the wall of the overcoater before rolling back down to the bottom thereby forming a second mixture of spherical media, graphite fines, and graphite spheres, removing the second mixture from the overcoater, sieving the second mixture to separate graphite spheres, charging the first mixture back into the overcoater, charging an additional quantity of graphite fines into the overcoater, adjusting processing parameters like overcoater dimensions, graphite fines charge, overcoater rotation speed, overcoater angle of rotation, and overcoater time of rotation, before repeating the steps until graphite fines are converted to graphite spheres.

  12. Two lozenges containing benzocaine assessed in the relief of sore throat.

    PubMed

    Kagan, G; Huddlestone, L; Wolstencroft, P

    1982-01-01

    A study has been conducted in general practice comparing two brands of lozenges, Merocaine (Merrell) and Tyrozets, (M.S.D.), in the management of acute sore throat and pharyngitis. Eighty-eight patients entered the between-patient study and each completed a diary card covering symptoms experienced and dosage used for each of the two drugs. The doctor reported upon the appearance of the throat and added antibiotics in cases of necessity, which was approximately for one-third of patients. Merocaine proved to be significantly superior to Tyrozets in producing rapid pain relief (within 15 minutes) and reduction of faucial and pharyngeal injection.

  13. Multi-Day Air Saturation at 20 and 22 FSW With Direct Ascent: Data Report on Project 92-09

    DTIC Science & Technology

    2002-03-01

    0802 0 air L/S; Divers 7, 8, 9, 10, 11, 12 0803 22 air R/B Feb 09 1919 22 air DMO entry, Diver 12 has scratchy throat and post-nasal drip, given aspirin...10,11, fsw 12 _ Galley is shipshape as is food. 1919 8 OK Robinson 12 describes scratchy throat & post nasal drip with ????? with purulent nasal...Ball 12 scratchy throat , sniffles, ASA 2 PO every 4 hrs 9 no c/o 7 no c/o 10 no c/o 11 mild congestion, Sudafed 60 mg Divers in good spirits 1250 8

  14. Detection of strep throat causing bacterium directly from medical swabs by touch spray-mass spectrometry.

    PubMed

    Jarmusch, Alan K; Pirro, Valentina; Kerian, Kevin S; Cooks, R Graham

    2014-10-07

    Strep throat causing Streptococcus pyogenes was detected in vitro and in simulated clinical samples by performing touch spray ionization-mass spectrometry. MS analysis took only seconds to reveal characteristic bacterial and human lipids. Medical swabs were used as the substrate for ambient ionization. This work constitutes the initial step in developing a non-invasive MS-based test for clinical diagnosis of strep throat. It is limited to the single species, S. pyogenes, which is responsible for the vast majority of cases. The method is complementary to and, with further testing, a potential alternative to current methods of point-of-care detection of S. pyogenes.

  15. Possible behavioural, energetic and demographic effects of displacement of red-throated divers

    USGS Publications Warehouse

    Dierschke, Volker; Furness, Robert W.; Gray, Carrie E.; Petersen, Ib Krag; Schmutz, Joel A.; Zydelis, Ramunas; Daunt, Francis

    2017-01-01

    This report comprises the main points of discussion and agreement during a workshop, held in Edinburgh in May 2017, to discuss how displacement might affect individuals and the Red-throated diver population; with additional information added by the scientists following the workshop.

  16. Eye, nose, hair, and throat: external anatomy of the head of a neonate gray whale (Cetacea, Mysticeti, Eschrichtiidae).

    PubMed

    Berta, Annalisa; Ekdale, Eric G; Zellmer, Nicholas T; Deméré, Thomas A; Kienle, Sarah S; Smallcomb, Meghan

    2015-04-01

    Information is scarce on gray whale (Eschrichtius robustus) anatomy and that of mysticetes in general. Dissection of the head of a neonatal gray whale revealed novel anatomical details of the eye, blowhole, incisive papilla with associated nasopalatine ducts, sensory hairs, and throat grooves. Compared to a similar sized right whale calf, the gray whale eyeball is nearly twice as long. The nasal cartilages of the gray whale, located between the blowholes, differ from the bowhead in having accessory cartilages. A small, fleshy incisive papilla bordered by two blind nasopalatine pits near the palate's rostral tip, previously undescribed in gray whales, may be associated with the vomeronasal organ, although histological evidence is needed for definitive identification. Less well known among mysticetes are the numerous elongated, stiff sensory hairs (vibrissae) observed on the gray whale rostrum from the ventral tip to the blowhole and on the mandible. These hairs are concentrated on the chin, and those on the lower jaw are arranged in a V-shaped pattern. We confirm the presence of two primary, anteriorly converging throat grooves, confined to the throat region similar to those of ziphiid and physeteroid odontocetes. A third, shorter groove occurs lateral to the left primary groove. The throat grooves in the gray whale have been implicated in gular expansion during suction feeding. © 2015 Wiley Periodicals, Inc.

  17. The impact of recurrent throat infection on children and their families.

    PubMed

    Howel, Denise; Webster, Simon; Hayes, Jane; Barton, Andrew; Donaldson, Liam

    2002-06-01

    Recurrent throat problems in children are common and have an impact on the family. The appropriateness of surgery will depend on both clinical and social factors. The aim of this study was to assess the impact on the whole family when a child is suffering from recurrent throat problems, and investigate related parental attitudes. A total of 1190 parents of children in northern England for whom tonsillectomy or adeno-tonsillectomy was a possible treatment option were sent a questionnaire covering social and clinical issues such as children's symptoms, the impact on family life and parental attitudes. The majority of children had experienced more than four episodes in the previous year, had their sleep affected and time off school. Most parents were worried and reported disruption to the family, including taking time off work and cross-infection. Parental disruption, worry and eagerness for surgery were significantly associated with the duration of episodes of throat problems and the number of episodes in the previous year, but not with duration of tonsillitis. Time off school, or parental time off work was significantly associated with parental worry and disruption, but not with eagerness for surgery. This work highlights the impact of recurrent throat problems and related parental attitudes, and will aid in striking a balance between clinical requirements and the needs and wishes of the family.

  18. Usefulness of Leukocyte Esterase Test Versus Rapid Strep Test for Diagnosis of Acute Strep Pharyngitis.

    PubMed

    Nibhanipudi, Kumara V

    2015-01-01

    A study to compare the usage of throat swab testing for leukocyte esterase on a test strip(urine dip stick-multi stick) to rapid strep test for rapid diagnosis of Group A Beta hemolytic streptococci in cases of acute pharyngitis in children. The testing of throat swab for leukocyte esterase on test strip currently used for urine testing may be used to detect throat infection and might be as useful as rapid strep. All patients who come with a complaint of sore throat and fever were examined clinically for erythema of pharynx, tonsils and also for any exudates. Informed consent was obtained from the parents and assent from the subjects. 3 swabs were taken from pharyngo-tonsillar region, testing for culture, rapid strep & Leukocyte Esterase. Total number is 100. Cultures 9(+); for rapid strep== 84(-) and16 (+); For LE== 80(-) and 20(+) From data configuration Rapid Strep versus LE test don't seem to be a random (independent) assignment but extremely aligned. The Statistical results show rapid and LE show very agreeable results. Calculated Value of Chi Squared Exceeds Tabulated under 1 Degree Of Freedom (P<.0.0001) reject Null HYPOTHESIS and Conclude Alternative Conclusions: Leukocyte esterase on throat swab is as useful as rapid strep test for rapid diagnosis of strep pharyngitis on test strip currently used for urine dip stick causing acute pharyngitis in children.

  19. FennoFlakes: a project for identifying flake graphite ores in the Fennoscandian shield and utilizing graphite in different applications

    NASA Astrophysics Data System (ADS)

    Palosaari, Jenny; Eklund, O.; Raunio, S.; Lindfors, T.; Latonen, R.-M.; Peltonen, J.; Smått, J.-H.; Kauppila, J.; Lund, S.; Sjöberg-Eerola, P.; Blomqvist, R.; Marmo, J.

    2016-04-01

    Natural graphite is a strategic mineral, since the European Commission stated (Report on critical raw materials for the EU (2014)) that graphite is one of the 20 most critical materials for the European Union. The EU consumed 13% of all flake graphite in the world but produced only 3%, which stresses the demand of the material. Flake graphite, which is a flaky version of graphite, forms under high metamorphic conditions. Flake graphite is important in different applications like batteries, carbon brushes, heat sinks etc. Graphene (a single layer of graphite) can be produced from graphite and is commonly used in many nanotechnological applications, e.g. in electronics and sensors. The steps to obtain pure graphene from graphite ore include fragmentation, flotation and exfoliation, which can be cumbersome and resulting in damaging the graphene layers. We have started a project named FennoFlakes, which is a co-operation between geologists and chemists to fill the whole value chain from graphite to graphene: 1. Exploration of graphite ores (geological and geophysical methods). 2. Petrological and geochemical analyses on the ores. 3. Development of fragmentation methods for graphite ores. 4. Chemical exfoliation of the enriched flake graphite to separate flake graphite into single and multilayer graphene. 5. Test the quality of the produced material in several high-end applications with totally environmental friendly and disposable material combinations. Preliminary results show that flake graphite in high metamorphic areas has better qualities compared to synthetic graphite produced in laboratories.

  20. Plantar Loading During Cutting While Wearing a Rigid Carbon Fiber Insert.

    PubMed

    Queen, Robin M; Abbey, Alicia N; Verma, Ravi; Butler, Robert J; Nunley, James A

    2014-02-12

    Context : Stress fractures are one of the most common injuries in sports, accounting for approximately 10% of all overuse injuries. Treatment of fifth metatarsal stress fractures involves both surgical and nonsurgical interventions. Fifth metatarsal stress fractures are difficult to treat because of the risks of delayed union, nonunion, and recurrent injuries. Most of these injuries occur during agility tasks, such as those performed in soccer, basketball, and lacrosse. Objective : To examine the effect of a rigid carbon graphite footplate on plantar loading during 2 agility tasks. Design :  Crossover study. Setting : Laboratory. Patients or Other Participants : A total of 19 recreational male athletes with no history of lower extremity injury in the past 6 months and no previous metatarsal stress fractures were tested. Main Outcome Measure(s) :  Seven 45° side-cut and crossover-cut tasks were completed in a shoe with or without a full-length rigid carbon plate. Testing order between the shoe conditions and the 2 cutting tasks was randomized. Plantar-loading data were recorded using instrumented insoles. Peak pressure, maximum force, force-time integral, and contact area beneath the total foot, the medial and lateral midfoot, and the medial, middle, and lateral forefoot were analyzed. A series of paired t tests was used to examine differences between the footwear conditions (carbon graphite footplate, shod) for both cutting tasks independently (α = .05). Results : During the side-cut task, the footplate increased total foot and lateral midfoot peak pressures while decreasing contact area and lateral midfoot force-time integral. During the crossover-cut task, the footplate increased total foot and lateral midfoot peak pressure and lateral forefoot force-time integral while decreasing total and lateral forefoot contact area. Conclusions : Although a rigid carbon graphite footplate altered some aspects of the plantar- pressure profile during cutting in uninjured participants, it was ineffective in reducing plantar loading beneath the fifth metatarsal.

  1. Plantar Loading During Cutting While Wearing a Rigid Carbon Fiber Insert

    PubMed Central

    Queen, Robin M.; Abbey, Alicia N.; Verma, Ravi; Butler, Robert J.; Nunley, James A.

    2014-01-01

    Context Stress fractures are one of the most common injuries in sports, accounting for approximately 10% of all overuse injuries. Treatment of fifth metatarsal stress fractures involves both surgical and nonsurgical interventions. Fifth metatarsal stress fractures are difficult to treat because of the risks of delayed union, nonunion, and recurrent injuries. Most of these injuries occur during agility tasks, such as those performed in soccer, basketball, and lacrosse. Objective: To examine the effect of a rigid carbon graphite footplate on plantar loading during 2 agility tasks. Design:  Crossover study. Setting: Laboratory. Patients or Other Participants: A total of 19 recreational male athletes with no history of lower extremity injury in the past 6 months and no previous metatarsal stress fractures were tested. Main Outcome Measure(s):  Seven 45° side-cut and crossover-cut tasks were completed in a shoe with or without a full-length rigid carbon plate. Testing order between the shoe conditions and the 2 cutting tasks was randomized. Plantar-loading data were recorded using instrumented insoles. Peak pressure, maximum force, force-time integral, and contact area beneath the total foot, the medial and lateral midfoot, and the medial, middle, and lateral forefoot were analyzed. A series of paired t tests was used to examine differences between the footwear conditions (carbon graphite footplate, shod) for both cutting tasks independently (α = .05). Results: During the side-cut task, the footplate increased total foot and lateral midfoot peak pressures while decreasing contact area and lateral midfoot force-time integral. During the crossover-cut task, the footplate increased total foot and lateral midfoot peak pressure and lateral forefoot force-time integral while decreasing total and lateral forefoot contact area. Conclusions: Although a rigid carbon graphite footplate altered some aspects of the plantar-pressure profile during cutting in uninjured participants, it was ineffective in reducing plantar loading beneath the fifth metatarsal. PMID:24955620

  2. 21 CFR 874.1 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., and throat devices intended for human use that are in commercial distribution. (b) The identification..., nose, and throat device that has two or more types of uses (e.g., used both as a diagnostic device and...) Guidance documents referenced in this part are available on the Internet at http://www.fda.gov/cdrh...

  3. Tuvan Throat Singing and Harmonics

    ERIC Educational Resources Information Center

    Ruiz, Michael J.; Wilken, David

    2018-01-01

    Tuvan throat singing, also called overtone singing, provides for an exotic demonstration of the physics of harmonics as well as introducing an Asian musical aesthetic. A low fundamental is sung and the singer skillfully alters the resonances of the vocal system to enhance an overtone (harmonic above the fundamental). The result is that the…

  4. Trying Not to "Shove Religion down Their Throats"

    ERIC Educational Resources Information Center

    King, Jason

    2015-01-01

    This article attempts two tasks. First, to clarify how the claim that colleges and universities may "shove religion down students' throats" has a historical background. Second, to indicate how pedagogical strategies--like service learning, discussions, paper revisions, and "Just in Time Teaching" exercises--can be used in ways…

  5. The Symptomatic Persian Gulf Veterans Protocol: An Analysis of Risk Factors with an Immunologic and Neuropsychiatric Assessment.

    DTIC Science & Technology

    1999-01-01

    Evaluation of peripheral blood mononuclear cells, urine and throat cultures samples for the presence of mycoplasma or ureaplasma organisms by...c) by PCR with a universal mycoplasma primer. Mycoplasma or ureaplasma were detected frequently in urine and throat swabs, however no significant

  6. Professional Implications of the Expansion of Retail-Based Clinics into Community Pharmacies

    DTIC Science & Technology

    2007-01-25

    Common Illnesses Allergies (ages 6+), Bronchitis (ages 10-64), Ear Infections, Pink Eye and Styes, $49 & Strep Throat Bladder Infections (females...ages 12-64) & $59 Strep Throat Skin Conditions Athletes Foot, Cold Sores, Deer Tick Bite, Impetigo, Minor Bums & Rashes, $49 Minor Skin Infection, Poison

  7. Effectiveness of nurse-led clinics on service delivery and clinical outcomes in adults with chronic ear, nose and throat complaints: a systematic review.

    PubMed

    Whiteford, Caroline; White, Sarahlouise; Stephenson, Matthew

    2016-04-01

    Ear, nose and throat complaints are very common and can cause significant disruption to patients' lives. Many conditions are of a chronic nature and are not currently managed in a timely manner by general practitioners in the community. This may be due to a lack of specialized knowledge, necessary diagnostic equipment or time for lengthy patient education on management of their condition. A nurse-led model of care may be an effective alternative. To examine the effectiveness of nurse-led clinics on adults with chronic ear, nose and throat complaints. Adult patients, aged 18 years and older, attending ear, nose and throat clinics, regardless of the complaint. Nurse-led care in general practice and acute care in which the nurse was identified as taking a lead role in the care of the patients with chronic ear, nose and throat complaints. General practitioner-led care, or ear, nose and throat consultant-led care, sometimes described as "standard care". Service delivery outcomes, clinical and health outcomes and financial outcomes. Any relevant quantitative studies published in English between 1980 and 2013 were considered. A standardized three-step search strategy aimed to find both published and unpublished studies. Databases searched include PubMed, CINAHL, Cochrane Library (CENTRAL), Scopus, Embase, MedNar and ProQuest Theses and Dissertations. Methodological validity was assessed independently by two reviewers using standardized critical appraisal instruments from the Joanna Briggs Institute. Due to methodological heterogeneity of the included studies, no statistical pooling was possible and all results are presented narratively. The search identified 13,536 titles, of which 20 potentially relevant articles were retrieved. Of these 20, 17 were excluded following full-text review leaving three studies that were assessed for methodological quality and included in the review. Service delivery outcome findings were that patient satisfaction was equal or higher and waiting times were shorter in nurse led clinics. The other service delivery outcomes were not addressed. Clinical and health outcomes findings were that lower pain/discomfort levels were demonstrated in nurse led clinics but other clinical/health outcomes were not addressed. Financial outcomes findings were that nurse-led clinics were cost effective when compared with medical-led clinics. While all studies reported evidence of the effectiveness of nurse-led clinics in service delivery and clinical outcomes in adults with chronic ear, nose and throat complaints, most of the data was self-reported and many of the outcomes of interest were not considered. The lack of experimental trials means that the level of evidence is low and further research is needed. There was also not enough detail in the financial outcomes from which clear conclusions of the cost benefit of nurse-led clinics could be drawn. Evidence from included studies indicated higher levels of patient satisfaction, cost benefits and lower levels of pain/discomfort in nurse-led clinics, which suggests that nurse-led ear, nose and throat clinics may be considered in the management of adult patients with ear, nose and throat complaints. Currently there is little evidence examining the effectiveness of nurse-led ear, nose and throat clinics. Areas to be addressed by future research should include: levels of patient education, booking queues, levels of self-treatment change in presentation to clinic episodes, reinfection rates, prevention and cure and representation of patients at clinics for same complaint.

  8. Treasure Na-ion anode from trash coke by adept electrolyte selection

    NASA Astrophysics Data System (ADS)

    Cabello, Marta; Chyrka, Taras; Klee, Rafael; Aragón, María J.; Bai, Xue; Lavela, Pedro; Vasylchenko, Gennadiy M.; Alcántara, Ricardo; Tirado, José L.; Ortiz, Gregorio F.

    2017-04-01

    Converting 'trash' waste residua to active functional materials 'treasure' with high added value is being regarded as a promising way to achieve the sustainable energy demands. Carbonaceous materials cannot insert sodium except when graphite co-intercalates solvents such as diglyme. Here, we show that petroleum coke and shale coke annealed at different temperatures can also insert sodium by reversible intercalation phenomena in a diglyme-based electrolyte. The structural and morphological studies will reveal significant differences justifying their distinct electrochemical behavior. Galvanostatic tests exhibit a flat plateau at about 0.7 V ascribable to the reversible reaction. At the end of the discharge, a Stage-I ternary intercalation compound is detected. Two diglyme molecules are co-intercalated per alkali ion, as evidenced by 1-D Patterson diagrams, FTIR and TGA analyses. The full sodium-ion cell made with P-2500/NaPF6(diglyme)/Na3V2(PO4)3 delivered an initial reversible capacity of 75 mA h g-1 at C rate and an average potential of 2.7 V. Thus, the full cell provides an energy density of 202 W h kg-1. This sodium-ion system can be considered a promising power source that encourages the potential use of low-cost energy storage systems.

  9. Damage-free back channel wet-etch process in amorphous indium-zinc-oxide thin-film transistors using a carbon-nanofilm barrier layer.

    PubMed

    Luo, Dongxiang; Zhao, Mingjie; Xu, Miao; Li, Min; Chen, Zikai; Wang, Lang; Zou, Jianhua; Tao, Hong; Wang, Lei; Peng, Junbiao

    2014-07-23

    Amorphous indium-zinc-oxide thin film transistors (IZO-TFTs) with damage-free back channel wet-etch (BCE) process were investigated. A carbon (C) nanofilm was inserted into the interface between IZO layer and source/drain (S/D) electrodes as a barrier layer. Transmittance electron microscope images revealed that the 3 nm-thick C nanofilm exhibited a good corrosion resistance to a commonly used H3PO4-based etchant and could be easily eliminated. The TFT device with a 3 nm-thick C barrier layer showed a saturated field effect mobility of 14.4 cm(2) V(-1) s(-1), a subthreshold swing of 0.21 V/decade, an on-to-off current ratio of 8.3 × 10(10), and a threshold voltage of 2.0 V. The favorable electrical performance of this kind of IZO-TFTs was due to the protection of the inserted C to IZO layer in the back-channel-etch process. Moreover, the low contact resistance of the devices was proved to be due to the graphitization of the C nanofilms after annealing. In addition, the hysteresis and thermal stress testing confirmed that the usage of C barrier nanofilms is an effective method to fabricate the damage-free BCE-type devices with high reliability.

  10. Outbreak of pyogenic abscesses after diphtheria and tetanus toxoids and pertussis vaccination.

    PubMed

    Simon, P A; Chen, R T; Elliott, J A; Schwartz, B

    1993-05-01

    Nine children who received diphtheria and tetanus toxoids and pertussis vaccine from the same vial at a clinic in Colorado developed pyogenic abscesses at the site of injection. Eight abscesses required surgical drainage and five children were hospitalized. Group A Streptococcus (GAS) was cultured from eight wounds and Staphylococcus aureus was also isolated from four. Epidemiologic investigation revealed that within the hour of the first child's vaccination, three children had been diagnosed in the clinic with GAS pharyngitis. GAS recovered from repeat throat swabs from two of these children and the eight case-isolates were all serotype M-12, T-12 and had identical immunoblot patterns on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Laboratory simulation studies demonstrated that GAS can survive for at least 4 days on the external surface of a vaccine vial rubber stopper and contaminate needles inserted through the stopper. Swabbing the stopper with 70% isopropyl alcohol resulted in effective disinfection. To prevent potential contamination meticulous attention to sterile technique is important when withdrawing vaccine from multidose vaccine vials.

  11. A Comparison of Combustion Dynamics for Multiple 7-Point Lean Direct Injection Combustor Configurations

    NASA Technical Reports Server (NTRS)

    Tacina, K. M.; Hicks, Y. R.

    2017-01-01

    The combustion dynamics of multiple 7-point lean direct injection (LDI) combustor configurations are compared. LDI is a fuel-lean combustor concept for aero gas turbine engines in which multiple small fuel-air mixers replace one traditionally-sized fuel-air mixer. This 7-point LDI configuration has a circular cross section, with a center (pilot) fuel-air mixer surrounded by six outer (main) fuel-air mixers. Each fuel-air mixer consists of an axial air swirler followed by a converging-diverging venturi. A simplex fuel injector is inserted through the center of the air swirler, with the fuel injector tip located near the venturi throat. All 7 fuel-air mixers are identical except for the swirler blade angle, which varies with the configuration. Testing was done in a 5-atm flame tube with inlet air temperatures from 600 to 800 F and equivalence ratios from 0.4 to 0.7. Combustion dynamics were measured using a cooled PCB pressure transducer flush-mounted in the wall of the combustor test section.

  12. Voronoi-Tessellated Graphite Produced by Low-Temperature Catalytic Graphitization from Renewable Resources.

    PubMed

    Zhao, Leyi; Zhao, Xiuyun; Burke, Luke T; Bennett, J Craig; Dunlap, Richard A; Obrovac, Mark N

    2017-09-11

    A highly crystalline graphite powder was prepared from the low temperature (800-1000 °C) graphitization of renewable hard carbon precursors using a magnesium catalyst. The resulting graphite particles are composed of Voronoi-tessellated regions comprising irregular sheets; each Voronoi-tessellated region having a small "seed" particle located near their centroid on the surface. This suggests nucleated outward growth of graphitic carbon, which has not been previously observed. Each seed particle consists of a spheroidal graphite shell on the inside of which hexagonal graphite platelets are perpendicularly affixed. This results in a unique high surface area graphite with a high degree of graphitization that is made with renewable feedstocks at temperatures far below that conventionally used for artificial graphites. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Influence of Metal-Coated Graphite Powders on Microstructure and Properties of the Bronze-Matrix/Graphite Composites

    NASA Astrophysics Data System (ADS)

    Zhao, Jian-hua; Li, Pu; Tang, Qi; Zhang, Yan-qing; He, Jian-sheng; He, Ke

    2017-02-01

    In this study, the bronze-matrix/x-graphite (x = 0, 1, 3 and 5%) composites were fabricated by powder metallurgy route by using Cu-coated graphite, Ni-coated graphite and pure graphite, respectively. The microstructure, mechanical properties and corrosive behaviors of bronze/Cu-coated-graphite (BCG), bronze/Ni-coated-graphite (BNG) and bronze/pure-graphite (BPG) were characterized and investigated. Results show that the Cu-coated and Ni-coated graphite could definitely increase the bonding quality between the bronze matrix and graphite. In general, with the increase in graphite content in bronze-matrix/graphite composites, the friction coefficients, ultimate density and wear rates of BPG, BCG and BNG composites all went down. However, the Vickers microhardness of the BNG composite would increase as the graphite content increased, which was contrary to the BPG and BCG composites. When the graphite content was 3%, the friction coefficient of BNG composite was more stable than that of BCG and BPG composites, indicating that BNG composite had a better tribological performance than the others. Under all the values of applied loads (10, 20, 40 and 60N), the BCG and BNG composites exhibited a lower wear rate than BPG composite. What is more, the existence of nickel in graphite powders could effectively improve the corrosion resistance of the BNG composite.

  14. WITHDRAWN: Grommets (ventilation tubes) for recurrent acute otitis media in children.

    PubMed

    Lau, Loretta; Mick, Paul; Nunez, Desmond A

    2018-04-06

    This is an update of a Cochrane review first published in The Cochrane Library in Issue 4, 2008 and previously updated in 2011.Acute suppurative otitis media is one of the most common infectious diseases in childhood. Recurrent acute otitis media is defined for the purposes of this review as either three or more acute infections of the middle ear cleft in a six-month period, or at least four episodes in a year. Strategies for managing the condition include the assessment and modification of risk factors where possible, repeated courses of antibiotics for each new infection, antibiotic prophylaxis and the insertion of ventilation tubes (grommets). To establish whether grommet insertion reduces the frequency of episodes of recurrent acute otitis media and the proportion of symptomatic children. The Cochrane Ear, Nose and Throat Disorders Group (CENTDG) Trials Search Co-ordinator searched the CENTDG Trials Register; Central Register of Controlled Trials (CENTRAL 2014, Issue 10); PubMed; EMBASE; CINAHL; Web of Science; Clinicaltrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 6 November 2014. Randomised controlled trials comparing grommet insertion versus control (antibiotics/other treatments/no treatment) for recurrent acute otitis media in children aged from 0 to 16 years. Two authors independently selected studies. Three authors independently assessed study quality and extracted data. We synthesised data descriptively. Two randomised controlled trials with a total of 148 participants are included in this review. The overall risk of bias in the studies is unclear.The first study randomised 95 children to grommets or control (antibiotic treatment of acute otitis media episodes). For the primary outcome, this study showed that grommet insertion leads to a mean reduction of 1.5 episodes of acute otitis media in the first six months after treatment. In six months of follow-up significantly more children in the grommet group had no episodes of acute otitis media (P value < 0.001). Complications of surgery included grommet blockage with acute otitis media requiring re-operation within six months in 3/54 children who underwent grommet insertion. Adverse effects were not documented in the control group. The following pre-defined secondary outcomes were not reported: change in symptom scores for otalgia or otorrhoea, alteration in the frequency of otalgia or otorrhoea, and number of days at nursery or school lost secondary to acute otitis media.The second study reported on 53 of 68 children who were randomised to grommet insertion or six months of once a day sulfamethoxazole and trimethoprim antibiotic prophylaxis. There was no significant difference in the primary outcome, number of episodes of acute otitis media, during the six-month follow-up between grommet insertion and antibiotic treatment groups (64.5% in the surgical group versus 45.4% in the antibiotic group had no recurrence, P value = 0.4). Two participants underwent grommet re-insertion to replace extruded tubes during the follow-up period. The only other adverse effect reported was the development of a skin rash in two patients in the medical group. Other pre-defined secondary outcome measures were not reported. The study has a high risk of bias and the results should be interpreted cautiously. Grommets significantly increase the number of acute otitis media-free children in the first six months after insertion compared to children who receive no treatment. Grommet insertion maybe of equivalent efficacy to once a day antibiotic prophylaxis. Further research is required to confirm the advantage of grommets over no treatment, investigate the effect beyond six months, compare grommet effectiveness against alternative active treatments and confirm the low risk of adverse effects compared to no treatment and all active treatments in recurrent acute otitis media. In the interim clinicians should consider the possible adverse effects of grommet insertion and alternative treatments before recommending surgery.

  15. Producing graphite with desired properties

    NASA Technical Reports Server (NTRS)

    Dickinson, J. M.; Imprescia, R. J.; Reiswig, R. D.; Smith, M. C.

    1971-01-01

    Isotropic or anisotropic graphite is synthesized with precise control of particle size, distribution, and shape. The isotropic graphites are nearly perfectly isotropic, with thermal expansion coefficients two or three times those of ordinary graphites. The anisotropic graphites approach the anisotropy of pyrolytic graphite.

  16. Brazing graphite to graphite

    DOEpatents

    Peterson, George R.

    1976-01-01

    Graphite is joined to graphite by employing both fine molybdenum powder as the brazing material and an annealing step that together produce a virtually metal-free joint exhibiting properties similar to those found in the parent graphite. Molybdenum powder is placed between the faying surfaces of two graphite parts and melted to form molybdenum carbide. The joint area is thereafter subjected to an annealing operation which diffuses the carbide away from the joint and into the graphite parts. Graphite dissolved by the dispersed molybdenum carbide precipitates into the joint area, replacing the molybdenum carbide to provide a joint of virtually graphite.

  17. Method of Joining Graphite Fibers to a Substrate

    NASA Technical Reports Server (NTRS)

    Beringer, Durwood M. (Inventor); Caron, Mark E. (Inventor); Taddey, Edmund P. (Inventor); Gleason, Brian P. (Inventor)

    2014-01-01

    A method of assembling a metallic-graphite structure includes forming a wetted graphite subassembly by arranging one or more layers of graphite fiber material including a plurality of graphite fibers and applying a layer of metallization material to ends of the plurality of graphite fibers. At least one metallic substrate is secured to the wetted graphite subassembly via the layer of metallization material.

  18. Pressure recovery performance of conical diffusers at high subsonic Mach numbers

    NASA Technical Reports Server (NTRS)

    Dolan, F. X.; Runstadler, P. W., Jr.

    1973-01-01

    The pressure recovery performance of conical diffusers has been measured for a wide range of geometries and inlet flow conditions. The approximate level and location (in terms of diffuser geometry of optimum performance were determined. Throat Mach numbers from low subsonic (m sub t equals 0.2) through choking (m sub t equals 1.0) were investigated in combination with throat blockage from 0.03 to 0.12. For fixed Mach number, performance was measured over a fourfold range of inlet Reynolds number. Maps of pressure recovery are presented as a function of diffuser geometry for fixed sets of inlet conditions. The influence of inlet blockage, throat Mach number, and inlet Reynolds number is discussed.

  19. Quantum detection of wormholes.

    PubMed

    Sabín, Carlos

    2017-04-06

    We show how to use quantum metrology to detect a wormhole. A coherent state of the electromagnetic field experiences a phase shift with a slight dependence on the throat radius of a possible distant wormhole. We show that this tiny correction is, in principle, detectable by homodyne measurements after long propagation lengths for a wide range of throat radii and distances to the wormhole, even if the detection takes place very far away from the throat, where the spacetime is very close to a flat geometry. We use realistic parameters from state-of-the-art long-baseline laser interferometry, both Earth-based and space-borne. The scheme is, in principle, robust to optical losses and initial mixedness.

  20. Detection of strep throat causing bacterium directly from medical swabs by touch spray - mass spectrometry

    PubMed Central

    Jarmusch, Alan K.; Pirro, Valentina; Kerian, Kevin S.; Cooks, Graham

    2014-01-01

    Strep throat causing Streptococcus pyogenes was detected in vitro and in simulated clinical samples by performing touch spray ionization - mass spectrometry. MS analysis took only seconds to reveal characteristic bacterial and human lipids. Medical swabs were used as the substrate for ambient ionization. This work constitutes the initial step in developing a noninvasive MS-based test for clinical diagnosis of strep throat. It is limited to the single species, S. pyogenes, which is responsible for the vast majority of cases. The method is complementary to and, with further testing, a potential alternative to current methods of point-of-care detection of S. pyogenes. PMID:25102079

  1. Tuvan throat singing and harmonics

    NASA Astrophysics Data System (ADS)

    Ruiz, Michael J.; Wilken, David

    2018-05-01

    Tuvan throat singing, also called overtone singing, provides for an exotic demonstration of the physics of harmonics as well as introducing an Asian musical aesthetic. A low fundamental is sung and the singer skillfully alters the resonances of the vocal system to enhance an overtone (harmonic above the fundamental). The result is that the listener hears two pitches simultaneously. Harmonics such as H8, H9, H10, and H12 form part of a pentatonic scale and are commonly selected for melody tones by Tuvan singers. A real-time spectrogram is provided in a video (Ruiz M J 2018 Video: Tuvan Throat Singing and Harmonics http://mjtruiz.com/ped/tuva/) so that Tuvan harmonics can be visualized as they are heard.

  2. Composite carbon foam electrode

    DOEpatents

    Mayer, Steven T.; Pekala, Richard W.; Kaschmitter, James L.

    1997-01-01

    Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivty and power to system energy.

  3. The fast reciprocating magnetic probe system on the J-TEXT tokamak

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

    Li, Fuming; Chen, Zhipeng, E-mail: zpchen@hust.edu.cn; Zhuang, Ge

    The fast reciprocating magnetic probe (FRMP) system is newly developed on the Joint Texas Experimental Tokamak (J-TEXT) to measure the local magnetic fluctuations at the plasma edge. The magnetic probe array in the FRMP consists of four 2-dimensional magnetic probes arranged at different radial locations to detect local poloidal and radial magnetic fields. These probes are protected by a graphite and boron nitride casing to improve the frequency response of each probe; they are mounted on the head of a movable rod, which is oriented along radial direction at the top of the torus. In the experiments, multiple core diagnosticsmore » show that the insertion of the FRMP has little impact on the equilibrium of the plasma. Local magnetic fluctuations inside the last closed flux surface are successfully measured by the FRMP.« less

  4. Method and apparatus for spraying molten materials

    DOEpatents

    Glovan, R.J.; Tierney, J.C.; McLean, L.L.; Johnson, L.L.; Nelson, G.L.; Lee, Y.M.

    1996-06-25

    A metal spray apparatus is provided with a supersonic nozzle. Molten metal is injected into a gas stream flowing through the nozzle under pressure. By varying the pressure of the injected metal, the droplet can be made in various selected sizes with each selected size having a high degree of size uniformity. A unique one piece graphite heater provides easily controlled uniformity of temperature in the nozzle and an attached tundish which holds the pressurized molten metal. A unique U-shaped gas heater provides extremely hot inlet gas temperatures to the nozzle. A particularly useful application of the spray apparatus is coating of threads of a fastener with a shape memory alloy. This permits a fastener to be easily inserted and removed but provides for a secure locking of the fastener in high temperature environments. 12 figs.

  5. Embedded Si/Graphene Composite Fabricated by Magnesium-Thermal Reduction as Anode Material for Lithium-Ion Batteries.

    PubMed

    Zhu, Jiangliu; Ren, Yurong; Yang, Bo; Chen, Wenkai; Ding, Jianning

    2017-12-16

    Embedded Si/graphene composite was fabricated by a novel method, which was in situ generated SiO 2 particles on graphene sheets followed by magnesium-thermal reduction. The tetraethyl orthosilicate (TEOS) and flake graphite was used as original materials. On the one hand, the unique structure of as-obtained composite accommodated the large volume change to some extent. Simultaneously, it enhanced electronic conductivity during Li-ion insertion/extraction. The MR-Si/G composite is used as the anode material for lithium ion batteries, which shows high reversible capacity and ascendant cycling stability reach to 950 mAh·g -1 at a current density of 50 mA·g -1 after 60 cycles. These may be conducive to the further advancement of Si-based composite anode design.

  6. 76 FR 62164 - VASRD Improvement Forum-Updating Disability Criteria for the Respiratory System, Cardiovascular...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-06

    ... Respiratory System, Cardiovascular System, Hearing Impairment, and Ear, Nose and Throat Diseases AGENCY... System, Cardiovascular System, Hearing Impairment, and Ear, Nose and Throat Diseases. The purpose of this...) the Cardiovascular System (38 CFR 4.100-4.104), (3) the Impairment of Auditory Acuity (38 CFR 4.85 and...

  7. Acquisition of plumage polymorphism in white-throated sparrows

    Treesearch

    Carter T. Atkinson; C. John Ralph

    1980-01-01

    The White-throated Sparrow (Zonotrichia albicollis) was thought to be polymorphic in breeding plumage, having distinct white and tan phases that are bimodal in distribution and independent of sex. Vardy (1971), however, submitted evidence that plumage type is determined primarily by age, sex, and molt cycle. We reexamined this question by measuring plumage...

  8. The role of plumage polymorphism in dominance relationshipt of the white-throated sparrow

    Treesearch

    Doris J. Watt; C. John Ralph; Carter T. Atkinson

    1984-01-01

    We studied dominance behaviors of captive winter flocks of White-throated Sparrows (Zonotrichia albicollis) in central Pennsylvania. Preliminary tests with a small group of birds indicated that there might be differences in behaviors between color morphs if age and sexual differences were controlled. Studies of two larger groups produced...

  9. Mach Stability Improvements Using an Existing Second Throat Capability at the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Chan, David T.; Balakrishna, Sundareswara; Walker, Eric L.; Goodliff, Scott L.

    2015-01-01

    Recent data quality improvements at the National Transonic Facility have an intended goal of reducing the Mach number variation in a data point to within plus or minus 0.0005, with the ultimate goal of reducing the data repeatability of the drag coefficient for full-span subsonic transport models at transonic speeds to within half a drag count. This paper will discuss the Mach stability improvements achieved through the use of an existing second throat capability at the NTF to create a minimum area at the end of the test section. These improvements were demonstrated using both the NASA Common Research Model and the NTF Pathfinder-I model in recent experiments. Sonic conditions at the throat were verified using sidewall static pressure data. The Mach variation levels from both experiments in the baseline tunnel configuration and the choked tunnel configuration will be presented and the correlation between Mach number and drag will also be examined. Finally, a brief discussion is given on the consequences of using the second throat in its location at the end of the test section.

  10. Food-borne outbreak of group G streptococcal sore throat in an Israeli military base.

    PubMed Central

    Cohen, D.; Ferne, M.; Rouach, T.; Bergner-Rabinowitz, S.

    1987-01-01

    A food-borne outbreak of sore throat caused by Lancefield group G beta-haemolytic streptococci and involving 50 persons occurred in May 1983 in an Israeli military camp. All of the patients available for clinical examination had sore throat and difficulty in swallowing. Exudative tonsillitis occurred in 46% of the patients and the body temperature was above 37.5 degrees C in 81%. The pattern of attack was uniform over the base and 37 became ill during the night and morning of the 5 May. Thirty-two (84%) of the throat cultures taken from 37 patients grew group G beta-haemolytic streptococci. Eight of 29 contacts were positive for group G beta-haemolytic streptococci and 6 of the 28 foodhandlers examined had positive cultures of the same group. The organism was also isolated from one food sample. The epidemiological and laboratory investigations indicated that a food handler, a convalescent carrier of group G streptococci, might have been the source of infection. Assumptions on the potential of non-group A streptococci to cause epidemics are discussed. PMID:3678389

  11. Emergency core cooling system

    DOEpatents

    Schenewerk, William E.; Glasgow, Lyle E.

    1983-01-01

    A liquid metal cooled fast breeder reactor provided with an emergency core cooling system includes a reactor vessel which contains a reactor core comprising an array of fuel assemblies and a plurality of blanket assemblies. The reactor core is immersed in a pool of liquid metal coolant. The reactor also includes a primary coolant system comprising a pump and conduits for circulating liquid metal coolant to the reactor core and through the fuel and blanket assemblies of the core. A converging-diverging venturi nozzle with an intermediate throat section is provided in between the assemblies and the pump. The intermediate throat section of the nozzle is provided with at least one opening which is in fluid communication with the pool of liquid sodium. In normal operation, coolant flows from the pump through the nozzle to the assemblies with very little fluid flowing through the opening in the throat. However, when the pump is not running, residual heat in the core causes fluid from the pool to flow through the opening in the throat of the nozzle and outwardly through the nozzle to the assemblies, thus providing a means of removing decay heat.

  12. Mach Stability Improvements Using an Existing Second Throat Capability at the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Chan, David T.

    2015-01-01

    Recent data quality improvements at the National Transonic Facility (NTF) have an intended goal of reducing the Mach number variation in a data point to within unit vector A plus or minus 0.0005, with the ultimate goal of reducing the data repeatability of the drag coefficient for full-span subsonic transport models at transonic speeds to within half of a drag count. This paper will discuss the Mach stability improvements achieved through the use of an existing second throat capability at the NTF to create a minimum area at the end of the test section. These improvements were demonstrated using both the NASA Common Research Model and the NTF Pathfinder-I model in recent experiments. Sonic conditions at the throat were verified using sidewall static pressure data. The Mach variation levels from both experiments in the baseline tunnel configuration and the choked tunnel configuration will be presented. Finally, a brief discussion is given on the consequences of using the second throat in its location at the end of the test section.

  13. Thermally exfoliated graphite oxide

    NASA Technical Reports Server (NTRS)

    Prud'Homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor); Abdala, Ahmed (Inventor)

    2011-01-01

    A modified graphite oxide material contains a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, wherein the thermally exfoliated graphite oxide displays no signature of the original graphite and/or graphite oxide, as determined by X-ray diffraction.

  14. A feasibility service evaluation of screening and treatment of group A streptococcal pharyngitis in community pharmacies.

    PubMed

    Thornley, T; Marshall, G; Howard, P; Wilson, A P R

    2016-11-01

    The UK 5 year antimicrobial resistance strategy recognizes the role of point-of-care diagnostics to identify where antimicrobials are required, as well as to assess the appropriateness of the diagnosis and treatment. A sore throat test-and-treat service was introduced in 35 community pharmacies across two localities in England during 2014-15. Trained pharmacy staff assessed patients presenting with a sore throat using the Centor scoring system and patients meeting three or all four of the criteria were offered a throat swab test for Streptococcus pyogenes, Lancefield group A streptococci. Patients with a positive throat swab test were offered antibiotic treatment. Following screening by pharmacy staff, 149/367 (40.6%) patients were eligible for throat swab testing. Of these, only 36/149 (24.2%) were positive for group A streptococci. Antibiotics were supplied to 9.8% (n = 36/367) of all patients accessing the service. Just under half of patients that were not showing signs of a bacterial infection (60/123, 48.8%) would have gone to their general practitioner if the service had not been available. This study has shown that it is feasible to deliver a community-pharmacy-based screening and treatment service using point-of-care testing. This type of service has the potential to support the antimicrobial resistance agenda by reducing unnecessary antibiotic use and inappropriate antibiotic consumption. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.

  15. Changes in Hyolaryngeal Movement and Swallowing Function After Neuromuscular Electrical Stimulation in Patients With Dysphagia

    PubMed Central

    Lee, Hoo Young; Hong, Ji Seong; Lee, Kil Chan; Shin, Yoon-Kyum

    2015-01-01

    Objective To investigate immediate changes in hyolaryngeal movement and swallowing function after a cycle of neuromuscular electrical stimulation (NMES) on both submental and throat regions and submental placement alone in patients with dysphagia. Methods Fifteen patients with dysphagia were recruited. First, videofluoroscopic swallowing study (VFSS) was performed before NMES. All patients thereafter received a cycle of NMES by 2 methods of electrode placement: 1) both submental and throat regions and 2) submental placement alone concomitant with VFSS. The Penetration-Aspiration Score (PAS) and the NIH-Swallowing Safety Scale (NIH-SSS) were measured for swallowing function. Results During swallowing, hyolaryngeal descent significantly occurred by NMES on both submental and throat regions, and anterior displacement of hyolaryngeal complex was significant on submental placement alone. NMES on submental placement alone did not change the PAS and NIH-SSS. However, NMES on both submental and throat regions significantly reduced the NIH-SSS, although it did not change the PAS. Patients with no brainstem lesion and with dysphagia duration of <3 months showed significantly improved the NIH-SSS. Conclusion Immediate hyolaryngeal movement was paradoxically depressed after NMES on both submental and throat regions with significant reductions in the NIH-SSS but not the PAS, suggesting improvement in pharyngeal peristalsis and cricopharyngeal functions at the esophageal entry rather than decreased aspiration and penetration. The results also suggested that patients with dysphagia should be carefully screened when determining motor-level NMES. PMID:25932416

  16. Usefulness of Leukocyte Esterase Test Versus Rapid Strep Test for Diagnosis of Acute Strep Pharyngitis

    PubMed Central

    2015-01-01

    Objective: A study to compare the usage of throat swab testing for leukocyte esterase on a test strip(urine dip stick-multi stick) to rapid strep test for rapid diagnosis of Group A Beta hemolytic streptococci in cases of acute pharyngitis in children. Hypothesis: The testing of throat swab for leukocyte esterase on test strip currently used for urine testing may be used to detect throat infection and might be as useful as rapid strep. Methods: All patients who come with a complaint of sore throat and fever were examined clinically for erythema of pharynx, tonsils and also for any exudates. Informed consent was obtained from the parents and assent from the subjects. 3 swabs were taken from pharyngo-tonsillar region, testing for culture, rapid strep & Leukocyte Esterase. Results: Total number is 100. Cultures 9(+); for rapid strep== 84(-) and16 (+); For LE== 80(-) and 20(+) Statistics: From data configuration Rapid Strep versus LE test don’t seem to be a random (independent) assignment but extremely aligned. The Statistical results show rapid and LE show very agreeable results. Calculated Value of Chi Squared Exceeds Tabulated under 1 Degree Of Freedom (P<.0.0001) reject Null Hypothesis and Conclude Alternative Conclusions: Leukocyte esterase on throat swab is as useful as rapid strep test for rapid diagnosis of strep pharyngitis on test strip currently used for urine dip stick causing acute pharyngitis in children. PMID:27335975

  17. Passive Rocket Diffuser Testing: Reacting Flow Performance of Four Second-Throat Geometries

    NASA Technical Reports Server (NTRS)

    Jones, Daniel R.; Allgood, Daniel C.; Saunders, Grady P.

    2016-01-01

    Second-throat diffusers serve to isolate rocket engines from the effects of ambient back pressure. As one of the nation's largest rocket testing facilities, the performance and design limitations of diffusers are of great interest to NASA's Stennis Space Center. This paper describes a series of tests conducted on four diffuser configurations to better understand the effects of inlet geometry and throat area on starting behavior and boundary layer separation. The diffusers were tested for a duration of five seconds with a 1455-pound thrust, LO2/GH2 thruster to ensure they each reached aerodynamic steady state. The effects of a water spray ring at the diffuser exits and a water-cooled deflector plate were also evaluated. Static pressure and temperature measurements were taken at multiple axial locations along the diffusers, and Computational Fluid Dynamics (CFD) simulations were used as a tool to aid in the interpretation of data. The hot combustion products were confirmed to enable the diffuser start condition with tighter second throats than predicted by historical cold-flow data or the theoretical normal shock method. Both aerodynamic performance and heat transfer were found to increase with smaller diffuser throats. Spray ring and deflector cooling water had negligible impacts on diffuser boundary layer separation. CFD was found to accurately capture diffuser shock structures and full-flowing diffuser wall pressures, and the qualitative behavior of heat transfer. However, the ability to predict boundary layer separated flows was not consistent.

  18. Conspicuous female ornamentation and tests of male mate preference in threespine sticklebacks (Gasterosteus aculeatus).

    PubMed

    Wright, Daniel Shane; Pierotti, Michele E R; Rundle, Howard D; McKinnon, Jeffrey S

    2015-01-01

    Sexual selection drives the evolution of exaggerated male ornaments in many animal species. Female ornamentation is now acknowledged also to be common but is generally less well understood. One example is the recently documented red female throat coloration in some threespine stickleback (Gasterosteus aculeatus) populations. Although female sticklebacks often exhibit a preference for red male throat coloration, the possibility of sexual selection on female coloration has been little studied. Using sequential and simultaneous mate choice trials, we examined male mate preferences for female throat color, as well as pelvic spine color and standard length, using wild-captured threespine sticklebacks from the Little Campbell River, British Columbia. In a multivariate analysis, we found no evidence for a population-level mate preference in males, suggesting the absence of directional sexual selection on these traits arising from male mate choice. Significant variation was detected among males in their preference functions, but this appeared to arise from differences in their mean responsiveness across mating trials and not from variation in the strength (i.e., slope) of their preference, suggesting the absence of individual-level preferences as well. When presented with conspecific intruder males, male response decreased as intruder red throat coloration increased, suggesting that males can discriminate color and other aspects of phenotype in our experiment and that males may use these traits in intrasexual interactions. The results presented here are the first to explicitly address male preference for female throat color in threespine sticklebacks.

  19. Conspicuous Female Ornamentation and Tests of Male Mate Preference in Threespine Sticklebacks (Gasterosteus aculeatus)

    PubMed Central

    Wright, Daniel Shane; Pierotti, Michele E. R.; Rundle, Howard D.; McKinnon, Jeffrey S.

    2015-01-01

    Sexual selection drives the evolution of exaggerated male ornaments in many animal species. Female ornamentation is now acknowledged also to be common but is generally less well understood. One example is the recently documented red female throat coloration in some threespine stickleback (Gasterosteus aculeatus) populations. Although female sticklebacks often exhibit a preference for red male throat coloration, the possibility of sexual selection on female coloration has been little studied. Using sequential and simultaneous mate choice trials, we examined male mate preferences for female throat color, as well as pelvic spine color and standard length, using wild-captured threespine sticklebacks from the Little Campbell River, British Columbia. In a multivariate analysis, we found no evidence for a population-level mate preference in males, suggesting the absence of directional sexual selection on these traits arising from male mate choice. Significant variation was detected among males in their preference functions, but this appeared to arise from differences in their mean responsiveness across mating trials and not from variation in the strength (i.e., slope) of their preference, suggesting the absence of individual-level preferences as well. When presented with conspecific intruder males, male response decreased as intruder red throat coloration increased, suggesting that males can discriminate color and other aspects of phenotype in our experiment and that males may use these traits in intrasexual interactions. The results presented here are the first to explicitly address male preference for female throat color in threespine sticklebacks. PMID:25806520

  20. The action of macrosounds on graphite ore and derived products

    NASA Technical Reports Server (NTRS)

    Bradeteanu, C.; Dragan, O.

    1974-01-01

    A suspension of graphite ore, floated graphite, and the gangue left over from flotation were subjected to the action of macrosounds under determinant conditions. The following was found: (1) The graphite ore undergoes an efficient settling action. (2) The floated graphite is strongly crushed down to the dimensions of colloidal graphite. (3) The gangue left over from flotation can be further processed to recuperate graphite from its nuclei.

  1. Graphene prepared by thermal reduction–exfoliation of graphite oxide: Effect of raw graphite particle size on the properties of graphite oxide and graphene

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

    Dao, Trung Dung; Jeong, Han Mo, E-mail: hmjeong@mail.ulsan.ac.kr

    Highlights: • Effect of raw graphite particle size on properties of GO and graphene is reported. • Size of raw graphite affects oxidation degree and chemical structure of GO. • Highly oxidized GO results in small-sized but well-exfoliated graphene. • GO properties affect reduction degree, structure, and conductivity of graphene. - Abstract: We report the effect of raw graphite size on the properties of graphite oxide and graphene prepared by thermal reduction–exfoliation of graphite oxide. Transmission electron microscope analysis shows that the lateral size of graphene becomes smaller when smaller size graphite is used. X-ray diffraction analysis confirms that graphitemore » with smaller size is more effectively oxidized, resulting in a more effective subsequent exfoliation of the obtained graphite oxide toward graphene. X-ray photoelectron spectroscopy demonstrates that reduction of the graphite oxide derived from smaller size graphite into graphene is more efficient. However, Raman analysis suggests that the average size of the in-plane sp{sup 2}-carbon domains on graphene is smaller when smaller size graphite is used. The enhanced reduction degree and the reduced size of sp{sup 2}-carbon domains contribute contradictively to the electrical conductivity of graphene when the particle size of raw graphite reduces.« less

  2. Enhanced performance of graphite anode materials by AlF3 coating for lithium-ion batteries

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

    Ding, Fei; Xu, Wu; Choi, Daiwon

    2012-04-27

    In order to form the stable surface film and to further enhance the long-term cycling stability of the graphite anodes of lithium-ion batteries, the surface of graphite powders has been modified by AlF3 coating through chemical precipitation method. The AlF3-coated graphite shows no evident changes in the bulk structure and a thin AlF3-coating layer of about 2 nm thick is found to uniformly cover the graphite particles with 2 wt% AlF3 content. However, it delivers a higher initial discharge capacity and largely improved rate performances compared to the pristine graphite. Remarkably, AlF3 coated graphite demonstrated a much better cycle life.more » After 300 cycles, AlF3 coated graphite and uncoated graphite show capacity retention of 92% and 81%, respectively. XPS measurement shows that a more conductive solid electrode interface (SEI) layer was formed on AlF3 coated graphite as compared to uncoated graphite. SEM monograph also reveals that the AlF3-coated graphite particles have a much more stable surface morphology after long-term cycling. Therefore, the improved electrochemical performance of AlF3 coated graphite can be attributed to a more stable and conductive SEI formed on coated graphite anode during cycling process.« less

  3. Graphite

    USGS Publications Warehouse

    Robinson, Gilpin R.; Hammarstrom, Jane M.; Olson, Donald W.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    Graphite is a form of pure carbon that normally occurs as black crystal flakes and masses. It has important properties, such as chemical inertness, thermal stability, high electrical conductivity, and lubricity (slipperiness) that make it suitable for many industrial applications, including electronics, lubricants, metallurgy, and steelmaking. For some of these uses, no suitable substitutes are available. Steelmaking and refractory applications in metallurgy use the largest amount of produced graphite; however, emerging technology uses in large-scale fuel cell, battery, and lightweight high-strength composite applications could substantially increase world demand for graphite.Graphite ores are classified as “amorphous” (microcrystalline), and “crystalline” (“flake” or “lump or chip”) based on the ore’s crystallinity, grain-size, and morphology. All graphite deposits mined today formed from metamorphism of carbonaceous sedimentary rocks, and the ore type is determined by the geologic setting. Thermally metamorphosed coal is the usual source of amorphous graphite. Disseminated crystalline flake graphite is mined from carbonaceous metamorphic rocks, and lump or chip graphite is mined from veins in high-grade metamorphic regions. Because graphite is chemically inert and nontoxic, the main environmental concerns associated with graphite mining are inhalation of fine-grained dusts, including silicate and sulfide mineral particles, and hydrocarbon vapors produced during the mining and processing of ore. Synthetic graphite is manufactured from hydrocarbon sources using high-temperature heat treatment, and it is more expensive to produce than natural graphite.Production of natural graphite is dominated by China, India, and Brazil, which export graphite worldwide. China provides approximately 67 percent of worldwide output of natural graphite, and, as the dominant exporter, has the ability to set world prices. China has significant graphite reserves, and China’s graphite production is expected to increase, although rising labor costs and some mine production problems are developing. China is expected to continue to be the dominant exporter for the near future. Mexico and Canada export graphite mainly to the United States, which has not had domestic production of natural graphite since the 1950s. Most graphite deposits in the United States are too small, low-grade, or remote to be of commercial value in the near future, and the likelihood of discovering larger, higher-grade, or favorably located domestic deposits is unlikely. The United States is a major producer of synthetic graphite.

  4. Sexual Dimorphism in Melanin Pigmentation, Feather Coloration and Its Heritability in the Barn Swallow (Hirundo rustica)

    PubMed Central

    Saino, Nicola; Romano, Maria; Rubolini, Diego; Teplitsky, Celine; Ambrosini, Roberto; Caprioli, Manuela; Canova, Luca; Wakamatsu, Kazumasa

    2013-01-01

    Melanin is the main pigment in animal coloration and considerable variation in the concentrations of the two melanin forms (pheo- and eumlanin) in pigmented tissues exists among populations and individuals. Melanin-based coloration is receiving increasing attention particularly in socio-sexual communication contexts because the melanocortin system has been hypothesized to provide a mechanistic basis for covariation between coloration and fitness traits. However, with few notable exceptions, little detailed information is available on inter-individual and inter-population variation in melanin pigmentation and on its environmental, genetic and ontogenetic components. Here, we investigate melanin-based coloration in an Italian population of a passerine bird, the barn swallow (Hirundo rustica rustica), its sex- and age-related variation, and heritability. The concentrations of eu- and pheomelanin in the throat (brown) and belly (white-to-brownish) feathers differed between sexes but not according to age. The relative concentration of either melanin (Pheo:Eu) differed between sexes in throat but not in belly feathers, and the concentrations in males compared to females were larger in belly than in throat feathers. There were weak correlations between the concentrations of melanins within as well as among plumage regions. Coloration of belly feathers was predicted by the concentration of both melanins whereas coloration of throat feathers was only predicted by pheomelanin in females. In addition, Pheo:Eu predicted coloration of throat feathers in females and that of belly feathers in males. Finally, we found high heritability of color of throat feathers. Melanization was found to differ from that recorded in Hirundo rustica rustica from Scotland or from H. r. erythrogaster from North America. Hence, present results show that pigmentation strategies vary in a complex manner according to sex and plumage region, and also among geographical populations, potentially reflecting adaptation to different natural and sexual selection regimes, and that some coloration components seem to be highly heritable. PMID:23469134

  5. TOPPITS: Trial Of Proton Pump Inhibitors in Throat Symptoms. Study protocol for a randomised controlled trial.

    PubMed

    Watson, Gillian; O'Hara, James; Carding, Paul; Lecouturier, Jan; Stocken, Deborah; Fouweather, Tony; Wilson, Janet

    2016-04-01

    Persistent throat symptoms and Extra Oesophageal Reflux (EOR) are among the commonest reasons for attendance at a secondary care throat or voice clinic. There is a growing trend to treat throat symptom patients with proton pump inhibitors (PPIs) to suppress stomach acid, but most controlled studies fail to demonstrate a significant benefit of PPI over placebo. In addition, patient views on PPI use vary widely. A UK multi-centre, randomised, controlled trial for adults with persistent throat symptoms to compare the effectiveness of treatment with the proton pump inhibitor (PPI) lansoprazole versus placebo. The trial includes a six-month internal pilot, during which three sites will recruit 30 participants in total, to assess the practicality of the trial and assess the study procedures and willingness of the patient population to participate. If the pilot is successful, three additional sites will be opened to recruitment, and a further 302 participants recruited across the six main trial sites. Further trial sites may be opened, as necessary. The main trial will continue for a further 18 months. Participants will be followed up for 12 months from randomisation, throughout which both primary and secondary outcome data will be collected. The primary outcome is change in Reflux Symptom Index (RSI) score, the 'area standard' for this type of assessment, after 16 weeks (four months) of treatment. Secondary outcomes are RSI changes at 12 months after randomisation, Quality of Life assessment at four and 12 months, laryngeal mucosal changes, assessments of compliance and side effects, and patient-reported satisfaction. TOPPITS is designed to evaluate the relative effectiveness of treatment with a proton pump inhibitor versus placebo in patients with persistent throat symptoms. This will provide valuable information to clinicians and GPs regarding the treatment and management of care for these patients, on changes in symptoms, and in Quality of Life, over time. ISRCTN38578686 . Registered 17 April 2014.

  6. Evaluation of Simplexa Group A Strep Direct Kit Compared to Hologic Group A Streptococcal Direct Assay for Detection of Group A Streptococcus in Throat Swabs.

    PubMed

    Church, Deirdre L; Lloyd, Tracie; Larios, Oscar; Gregson, Daniel B

    2018-03-01

    Diagnosis of bacterial pharyngitis is confirmed by detection of group A Streptococcus (GAS) in patient throat samples. Testing of throat samples has historically relied on culture, but new molecular methods allow much faster test turnaround time (i.e., same day versus 48 to 72 h for culture). Our laboratory uses the Hologic GAS Direct (GASD) assay for screening more than 125,000 throat samples per year. Simplexa GAS Direct is a new real-time quantitative PCR (qPCR) assay that does not require initial DNA extraction. Performance of Simplexa qPCR was compared to GASD. A total of 289 throat swabs were collected from patients attending ambulatory clinics in Calgary, Alberta, Canada. A total of 60 (20.8%) of the samples were initially GAS positive by either method: 54 by both methods, 4 by Simplex qPCR alone, and 2 by GASD alone. An in-house PCR using a unique GAS primer set was used to resolve the 6 discrepant results. Overall, GASD compared to Simplexa qPCR had a sensitivity, specificity, positive predictive value, and negative predictive value of 93.1% versus 100%, 100% versus 100%, 100% versus 100%, and 98.31% versus 100%, respectively. Implementation of Simplexa qPCR in our laboratory setting would cost more but allow the high sample volume to be reported in half the time and save 0.62 medical laboratory technician (MLT) full-time equivalent (FTE). In comparison to culture, the implementation of Simplexa qPCR would save 2.79 medical laboratory assistant (MLA) FTE plus 0.94 MLT FTE. Simplexa qPCR has improved performance and diagnostic efficiency in a high-volume laboratory compared to GASD for GAS detection in throat swabs. Copyright © 2018 American Society for Microbiology.

  7. The prevalence of acute respiratory symptoms and role of protective measures among Malaysian hajj pilgrims.

    PubMed

    Deris, Zakuan Zainy; Hasan, Habsah; Sulaiman, Siti Amrah; Wahab, Mohd Suhaimi Ab; Naing, Nyi Nyi; Othman, Nor Hayati

    2010-01-01

    Respiratory symptoms including cough, runny nose, sore throat, and fever are the most common clinical manifestations faced by hajj pilgrims in Mecca. The aim of the study was to determine the prevalence of respiratory symptoms among Malaysian hajj pilgrims and the effect of a few protective measures taken by hajj pilgrims to reduce respiratory symptoms. A cross-sectional study was conducted by distributing survey forms to Malaysian hajj pilgrims at transit center before flying back to Malaysia. The recruitment of respondents to the survey was on a voluntary basis. A total of 387 survey forms were available for analysis. The mean age was 50.4 +/- 11.0 years. The common respiratory symptoms among Malaysian hajj pilgrims were: cough 91.5%, runny nose 79.3%, fever 59.2%, and sore throat 57.1%. The prevalence of hajj pilgrims with triad of cough, subjective fever, and sore throat were 40.1%. The symptoms lasted less than 2 weeks in the majority of cases. Only 3.6% did not suffer from any of these symptoms. Seventy-two percent of hajj pilgrims received influenza vaccination before departure and 72.9% wore facemasks. Influenza vaccination was not associated with any of respiratory symptoms but it was significantly associated with longer duration of sore throat. Wearing masks was significantly associated with sore throat and longer duration of sore throat and fever. The prevalence of respiratory symptoms was high among Malaysian hajj pilgrims and the current protective measures seemed inadequate to reduce it. Beside standardization of the term used in hajj studies, more collaborative effort should be taken to reduce respiratory symptoms. The hajj authority should prepare for the challenge of pandemic influenza by providing more healthcare facilities and implementation of more strict measures to reduce the transmission of pandemic influenza strain among hajj pilgrims.

  8. Strategic graphite, a survey

    USGS Publications Warehouse

    Cameron, Eugene N.; Weis, Paul L.

    1960-01-01

    Strategic graphite consists of certain grades of lump and flake graphite for which the United States is largely or entirely dependent on sources abroad. Lump graphite of high purity, necessary in the manufacture of carbon brushes, is imported from Ceylon, where it occurs in vein deposits. Flake graphite, obtained from deposits consisting of graphite disseminated in schists and other metamorphic rocks, is an essential ingredient of crucibles used in the nonferrous metal industries and in the manufacture of lubricants and packings. High-quality flake graphite for these uses has been obtained mostly from Madagascar since World War I. Some flake graphite of strategic grade has been produced, however, from deposits in Texas, Alabama, and Pennsylvania. The development of the carbon-bonded crucible, which does not require coarse flake, should lessen the competitive advantage of the Madagascar producers of crucible flake. Graphite of various grades has been produced intermittently in the United States since 1644. The principal domestic deposits of flake graphite are in Texas, Alabama, Pennsylvania, and New York. Reserves of flake graphite in these four States are very large, but production has been sporadic and on the whole unprofitable since World War I, owing principally to competition from producers in Madagascar. Deposits in Madagascar are large and relatively high in content of flake graphite. Production costs are low and the flake produced is of high quality. Coarseness of flake and uniformity of the graphite products marketed are cited as major advantages of Madagascar flake. In addition, the usability of Madagascar flake for various purposes has been thoroughly demonstrated, whereas the usability of domestic flake for strategic purposes is still in question. Domestic graphite deposits are of five kinds: deposits consisting of graphite disseminated in metamorphosed siliceous sediments, deposits consisting of graphite disseminated in marble, deposits formed by thermal or dynamothermal metamorphism of coal beds or other highly carbonaceous sediments, vein deposits, and contact metasomatic deposits in marble. Only the first kind comprises deposits sufficiently large and rich in flake graphite to be significant potential sources of strategic grades of graphite. Vein deposits in several localities are known, but none is known to contain substantial reserves of graphite of strategic quality.Large resources of flake graphite exist in central Texas, in northeastern Alabama, in eastern Pennsylvania, and in the eastern Adirondack Mountains of New York. Tonnages available, compared with the tonnages of flake graphite consumed annually in the United States, are very large. There have been indications that flake graphite from Texas, Alabama, and Pennsylvania can be used in clay-graphite crucibles as a substitute for Madagascar flake, and one producer has made progress in establishing markets for his flake products as ingredients of lubricants. The tonnages of various commercial grades of graphite recoverable from various domestic deposits, however, have not been established; hence, the adequacy of domestic resources of graphite in a time of emergency is not known.The only vein deposits from which significant quantities of lump graphite have been produced are those of the Crystal Graphite mine, Beaverhead County, Mont. The deposits are fracture fillings in Precambrian gneiss and pegmatite. Known reserves in the deposits are small. In Texas, numerous flake-graphite deposits occur in the Precambrian Packsaddle schist in Llano and Burnet Counties. Graphite disseminated in certain parts of this formation ranges from extremely fine to medium grained. The principal producer has been the mine of the Southwestern Graphite Co., west of the town of Burnet. Substantial reserves of medium-grained graphite are present in the deposit mined by the company. In northeastern Alabama, flake-graphite deposits occur in the Ashland mica schist in two belts that trend northeastward across Clay, Goosa, and Chilton Counties. The northeastern belt has been the most productive. About 40 mines have been operated at one time or another, but only a few have been active during or since World War I. The deposits consist of flake graphite disseminated in certain zones or "leads" consisting of quartz-mica-feldspar schists and mica quartzite. Most of past production has come from the weathered upper parts of the deposits, but unweathered rock has been mined at several localities. Reserves of weathered rock containing 3 to 5 percent graphite are very large, and reserves of unweathered rock are even greater. Flake graphite deposits in Chester County, Pa., have been worked intermittently since about 1890. The deposits consist of medium- to coarse-grained graphite disseminated in certain belts of the Pickering gneiss. The most promising deposit is one worked in the Benjamin Franklin and the Eynon Just mines. Reserves of weathered rock containing 1.5 percent graphite are of moderate size; reserves of unweathered rock are large. In the eastern Adirondack Mountains in New York there are two principal kinds of flake-graphite deposits: contact-metasomatic deposits and those consisting of flake graphite disseminated in quartz schist. The contact-metasomatic deposits are small, irregular, and very erratic in graphite content. The deposits in quartz schist are very large, persistent, and uniform in grade. There are large reserves of schist containing 3 to 5 percent graphite, but the graphite is relatively fine grained.

  9. CMB-13 research on carbon and graphite

    NASA Technical Reports Server (NTRS)

    Smith, M. C.

    1972-01-01

    Preliminary results of the research on carbon and graphite accomplished during this report period are presented. Included are: particle characteristics of Santa Maria fillers, compositions and density data for hot-molded Santa Maria graphites, properties of hot-molded Santa Maria graphites, and properties of hot-molded anisotropic graphites. Ablation-resistant graphites are also discussed.

  10. METHOD OF FABRICATING A GRAPHITE MODERATED REACTOR

    DOEpatents

    Kratz, H.R.

    1963-05-01

    S>A nuclear reactor formed of spaced bodies of uranium and graphite blocks is improved by diffusing helium through the graphite blocks in order to replace the air in the pores of the graphite with helium. The helium-impregnated graphite conducts heat better, and absorbs neutrons less, than the original air- impregnated graphite. (AEC)

  11. AGC-2 Irradiation Report

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

    Rohrbaugh, David Thomas; Windes, William; Swank, W. David

    The Next Generation Nuclear Plant (NGNP) will be a helium-cooled, very high temperature reactor (VHTR) with a large graphite core. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor (HTGR) designs.[ , ] Nuclear graphite H 451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphites have been developed and are considered suitable candidates for the new NGNP reactor design. To support the design and licensing of NGNP core components within a commercial reactor, a completemore » properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade with a specific emphasis on data related to the life limiting effects of irradiation creep on key physical properties of the NGNP candidate graphites. Based on experience with previous graphite core components, the phenomenon of irradiation induced creep within the graphite has been shown to be critical to the total useful lifetime of graphite components. Irradiation induced creep occurs under the simultaneous application of high temperatures, neutron irradiation, and applied stresses within the graphite components. Significant internal stresses within the graphite components can result from a second phenomenon—irradiation induced dimensional change. In this case, the graphite physically changes i.e., first shrinking and then expanding with increasing neutron dose. This disparity in material volume change can induce significant internal stresses within graphite components. Irradiation induced creep relaxes these large internal stresses, thus reducing the risk of crack formation and component failure. Obviously, higher irradiation creep levels tend to relieve more internal stress, thus allowing the components longer useful lifetimes within the core. Determining the irradiation creep rates of nuclear grade graphites is critical for determining the useful lifetime of graphite components and is a major component of the Advanced Graphite Creep (AGC) experiment.« less

  12. Stable dispersions of polymer-coated graphitic nanoplatelets

    NASA Technical Reports Server (NTRS)

    Nguyen, Sonbinh T. (Inventor); Stankovich, Sasha (Inventor); Ruoff, Rodney S. (Inventor)

    2011-01-01

    A method of making a dispersion of reduced graphite oxide nanoplatelets involves providing a dispersion of graphite oxide nanoplatelets and reducing the graphite oxide nanoplatelets in the dispersion in the presence of a reducing agent and a polymer. The reduced graphite oxide nanoplatelets are reduced to an extent to provide a higher C/O ratio than graphite oxide. A stable dispersion having polymer-treated reduced graphite oxide nanoplatelets dispersed in a dispersing medium, such as water or organic liquid is provided. The polymer-treated, reduced graphite oxide nanoplatelets can be distributed in a polymer matrix to provide a composite material.

  13. Structural disorder of graphite and implications for graphite thermometry

    NASA Astrophysics Data System (ADS)

    Kirilova, Martina; Toy, Virginia; Rooney, Jeremy S.; Giorgetti, Carolina; Gordon, Keith C.; Collettini, Cristiano; Takeshita, Toru

    2018-02-01

    Graphitization, or the progressive maturation of carbonaceous material, is considered an irreversible process. Thus, the degree of graphite crystallinity, or its structural order, has been calibrated as an indicator of the peak metamorphic temperatures experienced by the host rocks. However, discrepancies between temperatures indicated by graphite crystallinity versus other thermometers have been documented in deformed rocks. To examine the possibility of mechanical modifications of graphite structure and the potential impacts on graphite thermometry, we performed laboratory deformation experiments. We sheared highly crystalline graphite powder at normal stresses of 5 and 25 megapascal (MPa) and aseismic velocities of 1, 10 and 100 µm s-1. The degree of structural order both in the starting and resulting materials was analyzed by Raman microspectroscopy. Our results demonstrate structural disorder of graphite, manifested as changes in the Raman spectra. Microstructural observations show that brittle processes caused the documented mechanical modifications of the aggregate graphite crystallinity. We conclude that the calibrated graphite thermometer is ambiguous in active tectonic settings.

  14. Ear, nose and throat problems in Accident and Emergency.

    PubMed

    Reynolds, Tanya

    Nurses working in A&E departments throughout the UK frequently encounter patients with ear, nose and throat conditions. While the majority of these are straightforward, a small number are serious and even life-threatening. Tanya Reynolds discusses the nursing management of this group of patients and stresses the importance of appropriate assessment, pain management and referral.

  15. Know and Share the Facts about Flu Vaccination

    ERIC Educational Resources Information Center

    Grohskopf, Lisa

    2012-01-01

    Flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. It can cause mild to severe illness, and sometimes can lead to death. Symptoms of flu can include fever or a feverish feeling, cough, sore throat, runny or stuffy nose, muscle or body aches, headache, fatigue, vomiting, and diarrhea. Flu…

  16. Global ENT Outreach: Taking Ear, Nose, and Throat Treatment and Surgery Techniques to Ethiopia

    ERIC Educational Resources Information Center

    Wagner, Richard

    2007-01-01

    The author, as an otolaryngologist and the Director of Global ENT (Ear, Nose and Throat) Outreach, traveled to Ethiopia to help 11 children who could not breathe because of respiratory papillomas blocking their airways and who had been hospitalized for years. The disease, called juvenile respiratory papillomatosis, is what affected these 11…

  17. Vacuum polarization of a quantized scalar field in the thermal state in a long throat

    NASA Astrophysics Data System (ADS)

    Popov, Arkady A.

    2016-12-01

    Vacuum polarization of scalar fields in the background of a long throat is investigated. The field is assumed to be both massive or massless, with arbitrary coupling to the scalar curvature, and in a thermal state at an arbitrary temperature. Analytical approximation for ⟨φ2⟩ren is obtained.

  18. Using Evaluability Assessment to Improve Program Evaluation for the Blue-Throated Macaw Environmental Education Project in Bolivia

    ERIC Educational Resources Information Center

    Salvatierra da Silva, Daniela; Jacobson, Susan K.; Monroe, Martha C.; Israel, Glenn D.

    2016-01-01

    An evaluability assessment of a program to save a critically endangered bird helped prepare the Blue-throated Macaw Environmental Education Project for evaluation and program improvement. The evaluability assessment facilitated agreement among key stakeholders on evaluation criteria and intended uses of evaluation information in order to maximize…

  19. Coinfection with Hepatozoon sp. and Canine Distemper Virus in a Yellow-throated Marten ( Martes flavigula koreana) in Korea.

    PubMed

    Park, Surim; Choi, Ul Soo; Kim, Eun Ju; Lee, Jong Hyun; Lee, Hae Beom; Cho, Ho Seong; Kim, Wonil; Lim, Chae Woong; Kim, Bumseok

    2016-04-28

    We describe coinfection with Hepatozoon sp. and canine distemper virus (CDV) in a yellow-throated marten ( Martes flavigula koreana). We found Hepatozoon cysts in muscular tissue and viral inclusion bodies in the brain. Hepatozoon sp., and CDV was confirmed in blood and brain, respectively, by PCR.

  20. Significance of Hemolytic Colonies in Throat Cultures

    PubMed Central

    Quinn, Robert W.; Lowry, P. Nye

    1969-01-01

    These studies indicate that a single strain of hemolytic streptococci almost exclusively predominates the bacterial flora in patients with streptococcal infections and in the carrier state. One can proceed with confidence that, in isolating streptococci from throat swabs cultured on blood-agar plates, only a single hemolytic colony need be picked for serological grouping and typing. PMID:4888863

  1. Do Shale Pore Throats Have a Threshold Diameter for Oil Storage?

    PubMed Central

    Zou, Caineng; Jin, Xu; Zhu, Rukai; Gong, Guangming; Sun, Liang; Dai, Jinxing; Meng, Depeng; Wang, Xiaoqi; Li, Jianming; Wu, Songtao; Liu, Xiaodan; Wu, Juntao; Jiang, Lei

    2015-01-01

    In this work, a nanoporous template with a controllable channel diameter was used to simulate the oil storage ability of shale pore throats. On the basis of the wetting behaviours at the nanoscale solid-liquid interfaces, the seepage of oil in nano-channels of different diameters was examined to accurately and systematically determine the effect of the pore diameter on the oil storage capacity. The results indicated that the lower threshold for oil storage was a pore throat of 20 nm, under certain conditions. This proposed pore size threshold provides novel, evidence-based criteria for estimating the geological reserves, recoverable reserves and economically recoverable reserves of shale oil. This new understanding of shale oil processes could revolutionize the related industries. PMID:26314637

  2. Do Shale Pore Throats Have a Threshold Diameter for Oil Storage?

    PubMed

    Zou, Caineng; Jin, Xu; Zhu, Rukai; Gong, Guangming; Sun, Liang; Dai, Jinxing; Meng, Depeng; Wang, Xiaoqi; Li, Jianming; Wu, Songtao; Liu, Xiaodan; Wu, Juntao; Jiang, Lei

    2015-08-28

    In this work, a nanoporous template with a controllable channel diameter was used to simulate the oil storage ability of shale pore throats. On the basis of the wetting behaviours at the nanoscale solid-liquid interfaces, the seepage of oil in nano-channels of different diameters was examined to accurately and systematically determine the effect of the pore diameter on the oil storage capacity. The results indicated that the lower threshold for oil storage was a pore throat of 20 nm, under certain conditions. This proposed pore size threshold provides novel, evidence-based criteria for estimating the geological reserves, recoverable reserves and economically recoverable reserves of shale oil. This new understanding of shale oil processes could revolutionize the related industries.

  3. Static Investigation of a Multiaxis Thrust-Vectoring Nozzle With Variable Internal Contouring Ability

    NASA Technical Reports Server (NTRS)

    Wing, David J.; Mills, Charles T. L.; Mason, Mary L.

    1997-01-01

    The thrust efficiency and vectoring performance of a convergent-divergent nozzle were investigated at static conditions in the model preparation area of the Langley 16-Foot Transonic Tunnel. The diamond-shaped nozzle was capable of varying the internal contour of each quadrant individually by using cam mechanisms and retractable drawers to produce pitch and yaw thrust vectoring. Pitch thrust vectoring was achieved by either retracting the lower drawers to incline the throat or varying the internal flow-path contours to incline the throat. Yaw thrust vectoring was achieved by reducing flow area left of the nozzle centerline and increasing flow area right of the nozzle centerline; a skewed throat deflected the flow in the lateral direction.

  4. International strategic minerals inventory summary report; natural graphite

    USGS Publications Warehouse

    Krauss, U.H.; Schmidt, H.W.; Taylor, H.A.; Sutphin, D.M.

    1989-01-01

    Natural graphite is a crystalline mineral of pure carbon which normally occurs in the form of platelet-shaped crystals. It has important properties, such as chemical inertness, low thermal expansion, and lubricity, that make it almost irreplaceable for certain uses such as refractories and steelmaking. Graphite ore types are crystalline (flake and lump} or 'amorphous' (cryptocrystalline}. Refractory applications use the largest total amount of natural graphite, while the most important use of crystalline graphite is in crucibles for handling molten metals. All graphite deposits being mined today are found in the following metamorphic environments: (1) contact metamorphosed coal generally is a source of amorphous graphite; (2)disseminated crystalline flake graphite comes from syngenetic metasediments; and (3) crystalline lump graphite is found in epigenetic veins in high-grade metamorphic regions. Graphite may also occur as a trace mineral in ultrabasic rocks and pegmatites, but these are economically insignificant. The world's identified economically exploitable resources of crystalline graphite in major deposits are estimated to be about 9.7 million metric tons of concentrate. In-place resources of amorphous graphite are about 11.5 million metric tons. Of these, less than 2 percent of the crystalline ore and less than 1 percent of the amorphous ore are in western industrial countries. World mining production of natural graphite rose from 347,000 metric tons in 1973 to 659,000 metric tons in 1986, while the proportion produced by central economy countries increased from about 50 percent for the period from 1973 to 1978 to more than 64 percent in 1979 to 1986. It is estimated that crystalline flake graphite accounts for at least 180,000 metric tons of total annual world mining production of natural graphite, and amorphous graphite makes up the rest.

  5. High Power Flex-Propellant Arcjet Performance

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.

    2011-01-01

    A MW-class electrothermal arcjet based on a water-cooled, wall-stabilized, constricted arc discharge configuration was subjected to extensive performance testing using hydrogen and simulated ammonia propellants with the deliberate aim of advancing technology readiness level for potential space propulsion applications. The breadboard design incorporates alternating conductor/insulator wafers to form a discharge barrel enclosure with a 2.5-cm internal bore diameter and an overall length of approximately 1 meter. Swirling propellant flow is introduced into the barrel, and a DC arc discharge mode is established between a backplate tungsten cathode button and a downstream ringanode/ spin-coil assembly. The arc-heated propellant then enters a short mixing plenum and is accelerated through a converging-diverging graphite nozzle. This innovative design configuration differs substantially from conventional arcjet thrusters, in which the throat functions as constrictor and the expansion nozzle serves as the anode, and permits the attainment of an equilibrium sonic throat (EST) condition. During the test program, applied electrical input power was varied between 0.5-1 MW with hydrogen and simulated ammonia flow rates in the range of 4-12 g/s and 15-35 g/s, respectively. The ranges of investigated specific input energy therefore fell between 50-250 MJ/kg for hydrogen and 10-60 MJ/kg for ammonia. In both cases, observed arc efficiencies were between 40-60 percent as determined via a simple heat balance method based on electrical input power and coolant water calorimeter measurements. These experimental results were found to be in excellent agreement with theoretical chemical equilibrium predictions, thereby validating the EST assumption and enabling the utilization of standard TDK nozzle expansion analyses to reliably infer baseline thruster performance characteristics. Inferred specific impulse performance accounting for recombination kinetics during the expansion process implied nearly frozen flow in the nozzle and yielded performance ranges of 800-1100 sec for hydrogen and 400-600 sec for ammonia. Inferred thrust-to-power ratios were in the range of 30-10 lbf/MWe for hydrogen and 60-20 lbf/MWe for ammonia. Successful completion of this test series represents a fundamental milestone in the progression of high power arcjet technology, and it is hoped that the results may serve as a reliable touchstone for the future development of MW-class regeneratively-cooled flex-propellant plasma rockets.

  6. Transformation of graphite by tectonic and hydrothermal processes in an active plate boundary fault zone, Alpine Fault, New Zealand

    NASA Astrophysics Data System (ADS)

    Kirilova, Matina; Toy, Virginia; Timms, Nicholas; Halfpenny, Angela; Menzies, Catriona; Craw, Dave; Rooney, Jeremy; Giorgetti, Carolina

    2017-04-01

    Graphite is a material with one of the lowest frictional strengths, with coefficient of friction of 0.1 and thus in natural fault zones it may act as a natural solid lubricant. Graphitization, or the transformation of organic matter (carbonaceous material, or CM) into crystalline graphite, is induced by compositional and structural changes during diagenesis and metamorphism. The supposed irreversible nature of this process has allowed the degree of graphite crystallinity to be calibrated as an indicator of the peak temperatures reached during progressive metamorphism. We examine processes of graphite emplacement and deformation in the Alpine Fault Zone, New Zealand's active continental tectonic plate boundary. Raman spectrometry indicates that graphite in the distal, amphibolite-facies Alpine Schist, which experienced peak metamorphic temperatures up to 640 ◦C, is highly crystalline and occurs mainly along grain boundaries within quartzo-feldspathic domains. The subsequent mylonitisation in the Alpine Fault Zone resulted in progressive reworking of CM under lower temperature conditions (500◦C-600◦C) in a structurally controlled environment, resulting in spatial clustering in lower-strain protomylonites, and further foliation-alignment in higher-strain mylonites. Subsequent brittle deformation of the mylonitised schists resulted in cataclasites that contain over three-fold increase in the abundance of graphite than mylonites. Furthermore, cataclasites contain graphite with two different habits: highly-crystalline, foliated forms that are inherited mylonitic graphite; and lower-crystallinity, less mature patches of finer-grained graphite. The observed graphite enrichment and the occurrence of poorly-organised graphite in the Alpine Fault cataclasites could result from: i) hydrothermal precipitation from carbon-supersaturated fluids; and/or ii) mechanical degradation by structural disordering of mylonitic graphite combined with strain-induced graphite localisation. The lack of published systematic studies of mechanical modification of the structure of graphite inhibits further conclusion to be drawn. Thus, we performed laboratory deformation experiments during which we sheared highly crystalline graphite powder at room temperature, normal stresses of 5 MPa and 25 MPa and sliding velocities of 1 µm/s, 10 µm/s and 100 µm/s. The degree of graphite crystallinity, both in the starting and resulting materials, was analysed by Raman microspectroscopy. Our results demonstrate consistent decrease of graphite crystallinity with increasing shear strain. We conclude that: i) graphite 'thermometers' are unreliable in brittely deformed rocks; ii) a shear strain calibration of graphite 'thermometers' is needed; iii) fault creep is very likely responsible for the observed structural and textural characteristics of graphite in the Alpine Fault cataclasites. Finally, to investigate the possibility of hydrothermal origin for at least some of the graphite in the Alpine Fault cataclasites we will also present synchrotron FTIR and carbon isotope analysis of the Alpine fault rocks.

  7. Solvation-controlled lithium-ion complexes in a nonflammable solvent containing ethylene carbonate: structural and electrochemical aspects.

    PubMed

    Sogawa, Michiru; Kawanoue, Hikaru; Todorov, Yanko Marinov; Hirayama, Daisuke; Mimura, Hideyuki; Yoshimoto, Nobuko; Morita, Masayuki; Fujii, Kenta

    2018-02-28

    The structural and electrochemical properties of lithium-ion solvation complexes in a nonflammable organic solvent, tris(2,2,2-trifluoroethyl)phosphate (TFEP) containing ethylene carbonate (EC), were investigated using vibrational spectroscopic and electrochemical measurements. Based on quantitative Raman and infrared (IR) spectral analysis of the Li bis(trifluoromethanesulfonyl)amide (TFSA) salt in TFEP + EC electrolytes, we successfully evaluated the individual solvation numbers of EC (n EC ), TFEP (n TFEP ), and TFSA - (n TFSA ) in the first solvation sphere of the Li-ion. We found that the n EC value linearly increased with increasing EC mole fraction (x EC ), whereas the n TFEP and n TFSA values gradually decreased with increasing n EC . The ionic conductivity and viscosity (Walden plots) indicated that mainly Li + TFSA - ion pairs formed in neat TFEP (x EC = 0). This ion pair gradually dissociated into positively charged Li-ion complexes as x EC increased, which was consistent with the Raman/IR spectroscopy results. The redox reaction corresponding to an insertion/desertion of Li-ion into/from the graphite electrode occurred in the LiTFSA/TFEP + EC system at x EC ≥ 0.25. The same was not observed in the lower x EC cases. We discussed the relation between Li-ion solvation and electrode reaction behaviors at the molecular level and proposed that n EC plays a crucial role in the electrode reaction, particularly in terms of solid electrolyte interphase formation on the graphite electrode.

  8. Evaluation of co-cokes from bituminous coal with vacuum resid or decant oil, and evaluation of anthracites, as precursors to graphite

    NASA Astrophysics Data System (ADS)

    Nyathi, Mhlwazi S.

    2011-12-01

    Graphite is utilized as a neutron moderator and structural component in some nuclear reactor designs. During the reactor operaction the structure of graphite is damaged by collision with fast neutrons. Graphite's resistance to this damage determines its lifetime in the reactor. On neutron irradiation, isotropic or near-isotropic graphite experiences less structural damage than anisotropic graphite. The degree of anisotropy in a graphite artifact is dependent on the structure of its precursor coke. Currently, there exist concerns over a short supply of traditional precursor coke, primarily due to a steadily increasing price of petroleum. The main goal of this study was to study the anisotropic and isotropic properties of graphitized co-cokes and anthracites as a way of investigating the possibility of synthesizing isotropic or near-isotropic graphite from co-cokes and anthracites. Demonstrating the ability to form isotropic or near-isotropic graphite would mean that co-cokes and anthracites have a potential use as filler material in the synthesis of nuclear graphite. The approach used to control the co-coke structure was to vary the reaction conditions. Co-cokes were produced by coking 4:1 blends of vacuum resid/coal and decant oil/coal at temperatures of 465 and 500 °C for reaction times of 12 and 18 hours under autogenous pressure. Co-cokes obtained were calcined at 1420 °C and graphitized at 3000 °C for 24 hours. Optical microscopy, X-ray diffraction, temperature-programmed oxidation and Raman spectroscopy were used to characterize the products. It was found that higher reaction temperature (500 °C) or shorter reaction time (12 hours) leads to an increase in co-coke structural disorder and an increase in the amount of mosaic carbon at the expense of textural components that are necessary for the formation of anisotropic structure, namely, domains and flow domains. Characterization of graphitized co-cokes showed that the quality, as expressed by the degree of graphitization and crystallite dimensions, of the final product is dependent on the nature of the precursor co-coke. The methodology for studying anthracites was to select two anthracites on basis of rank, PSOC1515 being semi-anthracite and DECS21 anthracite. The selected anthracites were graphitized, in both native and demineralized states, under the same conditions as co-cokes. Products obtained from DECS21 showed higher degrees of graphitization and larger crystallite dimensions than products obtained from PSOC1515. Demineralization of anthracites served to increase the degree of graphitization, indicating that the minerals contained in these anthracites have no graphitization-enhancing ability. A larger crystallite length for products obtained from native versions, compared to demineralized versions, was attributed to a formation and decomposition of a silicon carbide during graphitization of native versions. In order to examine the anisotropic and isotropic properties, nuclear-grade graphite samples obtained from Oak Ridge National Laboratory (ORNL) and commercial graphite purchased from Fluka were characterized under similar conditions as graphitized co-cokes and anthracites. These samples served as representatives of "two extremes", with ORNL samples being the isotropic end and commercial graphite being the anisotropic end. Through evaluating relationships between structural parameters, it was observed that graphitized co-cokes are situated, structurally, somewhere between the "two extremes", whereas graphitized anthracites are closer to the anisotropic end. Basically, co-cokes have a better potential than anthracites to transform to isotropic or near-isotropic graphite upon graphitization. By co-coking vacuum resid/coal instead of decant oil/coal or using 500 °C instead of 465 °C, a shift away from commercial graphite towards ORNL samples was attained. Graphitizing a semi-anthracite or demineralizing anthracites before graphitization also caused a shift towards ORNL samples.

  9. EXPLORATORY DEVELOPMENT OF GRAPHITE MATERIALS.

    DTIC Science & Technology

    COMPOSITE MATERIALS), (* GRAPHITE , (*FIBERS, GRAPHITE ), (*LAMINATED PLASTICS, GRAPHITE ), MOLDINGS, EXTRUSION, VACUUM, EPOXY RESINS, FILAMENTS, STRESSES, TENSILE PROPERTIES, OXIDATION, PHYSICAL PROPERTIES.

  10. Clinical value of antistreptolysin O levels in adult patients with tonsillitis: report I.

    PubMed

    Trushin, Vladimir; Englender, Moshe

    2017-04-01

    To assess the clinical value of antistreptolysin O (ASO) level in adult patients with acute tonsillitis of group A beta-hemolytic streptococcus (GABHS) etiology and its interaction with the Centor score and throat cultures data. ASO antibody titers and throat cultures were obtained from 260 adult patients with acute tonsillitis of GABHS etiology initially proven by the Centor score. The results were compared with the group of 100 adult patients with recurrent tonsillitis who underwent tonsillectomy and with the group of 100 healthy adults. Throat cultures revealed GABHS-positive results in 69 acute cases (26.5%) and in 24 recurrent cases (24%), i.e., with no significant differences between the groups (p = 0.845). There was no significant difference between cases with GABHS-positive and with GABHS-negative throat culture in ASO titers results (mean 250 and 280, respectively, p = 0.44) but these titers were significantly higher than established normative data (p < 0.01). For the group of recurrent tonsillitis cases, the mean ASO titer was 363 being significantly higher in comparison with acute cases (p = 0.015). The ASO antibody titers are significantly higher than normative ranges in cases of acute tonsillitis in adults. The detection of the elevated titers may lead to early antibiotherapy to tonsillitis. The Centor score is supported by the ASO data and less supported by throat cultures data. Further research should reveal if these titers might have predictive value for possible further recurrence or serve as an indicator for tonsillectomy in cases of recurrent tonsillitis.

  11. Method and system for measuring multiphase flow using multiple pressure differentials

    DOEpatents

    Fincke, James R.

    2001-01-01

    An improved method and system for measuring a multiphase flow in a pressure flow meter. An extended throat venturi is used and pressure of the multiphase flow is measured at three or more positions in the venturi, which define two or more pressure differentials in the flow conduit. The differential pressures are then used to calculate the mass flow of the gas phase, the total mass flow, and the liquid phase. The method for determining the mass flow of the high void fraction fluid flow and the gas flow includes certain steps. The first step is calculating a gas density for the gas flow. The next two steps are finding a normalized gas mass flow rate through the venturi and computing a gas mass flow rate. The following step is estimating the gas velocity in the venturi tube throat. The next step is calculating the pressure drop experienced by the gas-phase due to work performed by the gas phase in accelerating the liquid phase between the upstream pressure measuring point and the pressure measuring point in the venturi throat. Another step is estimating the liquid velocity in the venturi throat using the calculated pressure drop experienced by the gas-phase due to work performed by the gas phase. Then the friction is computed between the liquid phase and a wall in the venturi tube. Finally, the total mass flow rate based on measured pressure in the venturi throat is calculated, and the mass flow rate of the liquid phase is calculated from the difference of the total mass flow rate and the gas mass flow rate.

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

    Gao, J.X.; Wei, B.Q.; Li, D.D.

    The evolution of microstructure in bainite during graphitization annealing at 680 °C of Jominy-quenched bars of an Al-Si bearing medium carbon (0.4C wt%) steel has been studied and compared with that in martensite by using light, scanning and transmission electron microscopy. The results show that the graphitization process in bainite is different from that in martensite in many aspects such as the initial carbon state, the behavior of cementite, the nucleation-growth feature and kinetics of formation of graphite spheroids during graphitization annealing, and the shape, size and distribution of these graphite spheroids. The fact that the graphitization in bainite canmore » produce more homogeneous graphite spheroids with more spherical shape and finer size in a shorter annealing time without the help of preexisting coring particles implies that bainite should be a better starting structure than martensite for making graphitic steel. - Highlights: • This article presents a microstructural characterization of formation of graphite spheroids in bainite. • Nucleation and growth characteristics of graphite spheroids formed in bainite and martensite are compared. • Bainite should be a better starting structure for making graphitic steel as results show.« less

  13. 40 CFR 436.380 - Applicability; description of the graphite subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... graphite subcategory. 436.380 Section 436.380 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Graphite Subcategory § 436.380 Applicability; description of the graphite subcategory. The provisions of this subpart are applicable to the mining and processing of naturally occurring graphite. ...

  14. 21 CFR 341.72 - Labeling of antihistamine drug products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... of the following: “relieves,” “alleviates,” “decreases,” “reduces,” or “dries”) “runny nose and... the nose or throat, and itchy, watery eyes due to hay fever” (which may be followed by one or both of... temporary relief of runny nose, sneezing, itching of the nose or throat, and itchy, watery eyes due to hay...

  15. 21 CFR 341.72 - Labeling of antihistamine drug products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... of the following: “relieves,” “alleviates,” “decreases,” “reduces,” or “dries”) “runny nose and... the nose or throat, and itchy, watery eyes due to hay fever” (which may be followed by one or both of... temporary relief of runny nose, sneezing, itching of the nose or throat, and itchy, watery eyes due to hay...

  16. 21 CFR 341.72 - Labeling of antihistamine drug products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... of the following: “relieves,” “alleviates,” “decreases,” “reduces,” or “dries”) “runny nose and... the nose or throat, and itchy, watery eyes due to hay fever” (which may be followed by one or both of... temporary relief of runny nose, sneezing, itching of the nose or throat, and itchy, watery eyes due to hay...

  17. 21 CFR 341.72 - Labeling of antihistamine drug products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of the following: “relieves,” “alleviates,” “decreases,” “reduces,” or “dries”) “runny nose and... the nose or throat, and itchy, watery eyes due to hay fever” (which may be followed by one or both of... temporary relief of runny nose, sneezing, itching of the nose or throat, and itchy, watery eyes due to hay...

  18. 21 CFR 341.72 - Labeling of antihistamine drug products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of the following: “relieves,” “alleviates,” “decreases,” “reduces,” or “dries”) “runny nose and... the nose or throat, and itchy, watery eyes due to hay fever” (which may be followed by one or both of... temporary relief of runny nose, sneezing, itching of the nose or throat, and itchy, watery eyes due to hay...

  19. Exceeding Parents' Expectations in Ear-Nose-Throat Outpatient Facilities: The Development and Analysis of a Questionnaire

    ERIC Educational Resources Information Center

    Margaritis, Eleftherios; Katharaki, Maria; Katharakis, George

    2012-01-01

    The study attempts to develop an outpatient service quality scale by investigating the key dimensions which assess parental satisfaction and provides a recommendation on an improved health service delivery system. The survey was conducted in an Ear-Nose-Throat outpatient clinic of a Greek public pediatric hospital. A total of 127 parents in…

  20. Atomization of liquids in a Pease-Anthony Venturi scrubber. Part II. Droplet dispersion.

    PubMed

    Gonçalves, J A S; Costa, M A M; Aguiar, M L; Coury, J R

    2004-12-10

    Droplet distribution is of fundamental importance to the performance of a Venturi scrubber. Ensuring good liquid distribution can increase performance at minimal liquid usage. In this study, droplet dispersion in a rectangular Pease-Anthony Venturi scrubber, operating horizontally, was examined both theoretically and experimentally. The Venturi throat cross-section was 24 mm x 35 mm, and the throat length varied from 63 to 140 mm. Liquid was injected through a single orifice (1.0 mm diameter) on the throat wall. This arrangement allowed the study of the influence of jet penetration on droplet distribution. Gas velocity at the throat was 58.3 and 74.6 m/s, and the liquid flow rate was 286, 559 and 853 ml/min. A probe with a 2.7 mm internal diameter was used to isokinetically remove liquid from several positions inside the equipment. It was possible to study liquid distribution close to the injection point. A new model for droplet dispersion, which incorporates the new description of the jet atomization process developed by the present authors in the first article of this series, is proposed and evaluated. The model predicted well the experimental data.

  1. Fluorescence spectroscopy for throat cancer detection using human saliva

    NASA Astrophysics Data System (ADS)

    Kumar, Pavan; Singh, Ashutosh; Zaffar, Mohammad; Pradhan, Asima

    2018-02-01

    Throat precancer detection using fluorescence from human saliva is reported here. It may be noted that accessing the throat for investigation is cumbersome and use of saliva as a diagnostic medium may ease the process. The study has been conducted on three groups of patients: oral squamous cell carcinoma (OSCC), dysplasia, and normal (control). An in-house developed compact set-up has been used for fluorescence measurements. The compact system consist of a 375 nm laser diode, collimating lens, long pass filter, fibers, and cuvette holder. Major and minor bands of flavin adenine dinucleotide (FAD) and porphyrin are observed in the spectra. A receiver operating characteristic (ROC) analysis has been used to evaluate the diagnostic performance. Area under the spectra has been chosen for discrimination among the groups and is able to differentiate OSCC to normal, dysplasia to normal, and OSCC to dysplasia with sensitivities 100% (48/48), 92% (32/35), 77% (37/48), and specificities 96% (50/52), 96% (50/52), 89% (31/35) with the accuracy of 98%, 94% and 82% respectively. Sensitivity and specificity, when differentiating OSCC to normal and dysplasia to normal, are significantly large, which indicates that human saliva may be an excellent diagnostic medium for early detection of throat cancer.

  2. A CFD Study of Turbojet and Single-Throat Ramjet Ejector Interaction

    NASA Technical Reports Server (NTRS)

    Chang, Ing; Hunter, Louis

    1996-01-01

    Supersonic ejector-diffuse systems have application in driving an advanced airbreathing propulsion system, consisting of turbojet engines acting as the primary and a single throat ramjet acting as the secondary. The turbojet engines are integrated into the single throat ramjet to minimize variable geometry and eliminate redundant propulsion components. The result is a simple, lightweight system that is operable from takeoff to high Mach numbers. At this high Mach number (approximately Mach 3.0), the turbojets are turned off and the high speed ramjet/scramjet take over and drive the vehicle to Mach 6.0. The turbojet-ejector-ramjet system consists of nonafterburning turbojet engines with ducting canted at 20 degrees to supply supersonic flow (downstream of CD nozzle) to the horizontal ramjet duct at a supply total pressure and temperature. Two conditions were modelled by a 2-D full Navier Stokes code at Mach 2.0. The code modelled the Fabri choke as well as the non-Fabri non critical case, using a computational throat to supply the back pressure. The results, which primarily predict the secondary mass flow rate and the mixed conditions at the ejector exit were in reasonable agreement with the 1-D cycle code (TBCC).

  3. [Study of bacterial flora in the oral cavity and stomach of elderly patients receiving nasogastric tube feeding].

    PubMed

    Matsuura, T; Suzuki, K; Yamakoshi, M; Yamamoto, T; Yamamoto, T; Yoshitomo, K; Tonegawa, K; Ariga, K; Odawara, F

    1997-05-01

    To investigate the significance of oropharyngeal flora and gastric flora in elderly patients receiving nasogastric tube feeding, throat secretions and gastric aspirates were cultured and the pH of the latter was measured. Of 116 bacterial isolates from throat secretions of 27 elderly patients, 30 were beta-streptococci and 28 were Pseudomonas aeruginosa. Bacteria isolated from gastric aspirates numbered 86 and 24 (27.9%) of them were the same species as those found in the throat secretions. Patients with gastric pH were below 3.5 had significantly lower concentrations of gram-negative bacili in gastric aspirates. We also studied oropharyngeal flora in 33 elderly patients who were admitted to Nagoyashi Koseiin Geriatric Hospital. The major bacterial isolates from throat swabs of bedridden patients were gram-negative bacilli and beta-streptococci, especially group B streptococci (GBS). We measured the level of antibody to GBS in these patients. Those from whom GBS were isolated had high titers. These results suggest that in elderly patients receiving enteral nasogastric) tube feeding, large numbers of bacteria colonize the oral cavity and stomach. The measurement of type-specific antibody to GBS may be useful in managing such patients.

  4. Sturge-Weber syndrome: ear, nose, and throat issues and neurologic status.

    PubMed

    Irving, Natasha D; Lim, Jae Hyung; Cohen, Bernard; Ferenc, Lisa M; Comi, Anne M

    2010-10-01

    The pathophysiology of Sturge-Weber syndrome is poorly understood, and ear, nose, and throat involvement is possible. These issues can result in frequent illnesses or airway obstruction, affecting patients' neurologic status. Patients with definite brain involvement who reported potential ear, nose, and throat issues on intake questionnaires underwent retrospective reviews of their medical records. We examined the relationships between these issues, secondary surgical interventions, and patients' neurologic status. The most common complaints involved the sinuses and frequent ear infections. Six patients underwent placement of ear tubes, leading to improvements in migraines and stroke-like episodes in one patient, and improved seizure control in four others. Obstructive sleep apnea was confirmed in three patients who underwent sleep studies. Tonsil or adenoid removal occurred in another three patients. Surgery resulted in marked improvements regarding excessive drooling, daytime sleepiness, and breathing problems. These findings suggest that ear, nose, and throat problems occur frequently in patients with Sturge-Weber Syndrome, and when repeated ear infections are associated with uncontrolled seizures, early placement of ear tubes may be beneficial. Furthermore, patients with facial tissue hypertrophy may be at risk for obstructive sleep apnea, and should be appropriately evaluated. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Method for producing thin graphite flakes with large aspect ratios

    DOEpatents

    Bunnell, L. Roy

    1993-01-01

    A method for making graphite flakes of high aspect ratio by the steps of providing a strong concentrated acid and heating the graphite in the presence of the acid for a time and at a temperature effective to intercalate the acid in the graphite; heating the intercalated graphite at a rate and to a temperature effective to exfoliate the graphite in discrete layers; subjecting the graphite layers to ultrasonic energy, mechanical shear forces, or freezing in an amount effective to separate the layes into discrete flakes.

  6. Physical, electrochemical, and thermal properties of granulated natural graphite as anodes for Li-ion batteries.

    PubMed

    Jo, Yong Nam; Park, Min-Sik; Kim, Jae-Hun; Kim, Young-Jun

    2013-05-01

    Two different types of granulated graphites were synthesized by blending and kneading of natural graphite with pitch followed by sintering methods. The electrochemical performances of granulated graphites were investigated as anode materials for use in Li-ion batteries. The blending type granulated graphite possesses a large amount of cavities and voids, while the kneading type granulated graphite has a relatively compact microstructure, which is responsible for a high tap density. Both granulated graphites show improved the initial coulombic efficiencies as a result of decrease of surface area by the granulations. In particular, the kneading type granulated graphite exhibits an excellent rate-capability without significant capacity loss. In addition, the thermal stabilities of both granulated graphites were also improved, which could be attributed to the decrease of active surface area due to pitch coating.

  7. Effect of Reacting Surface Density on the Overall Graphite Oxidation Rate

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

    Chang H. Oh; Eung Kim; Jong Lim

    2009-05-01

    Graphite oxidation in an air-ingress accident is presently a very important issue for the reactor safety of the very high temperature gas cooled-reactor (VHTR), the concept of the next generation nuclear plant (NGNP) because of its potential problems such as mechanical degradation of the supporting graphite in the lower plenum of the VHTR might lead to core collapse if the countermeasure is taken carefully. The oxidation process of graphite has known to be affected by various factors, including temperature, pressure, oxygen concentration, types of graphite, graphite shape and size, flow distribution, etc. However, our recent study reveals that the internalmore » pore characteristics play very important roles in the overall graphite oxidation rate. One of the main issues regarding graphite oxidation is the potential core collapse problem that may occur following the degradation of graphite mechanical strength. In analyzing this phenomenon, it is very important to understand the relationship between the degree of oxidization and strength degradation. In addition, the change of oxidation rate by graphite oxidation degree characterization by burn-off (ratio of the oxidized graphite density to the original density) should be quantified because graphite strength degradation is followed by graphite density decrease, which highly affects oxidation rates and patterns. Because the density change is proportional to the internal pore surface area, they should be quantified in advance. In order to understand the above issues, the following experiments were performed: (1)Experiment on the fracture of the oxidized graphite and validation of the previous correlations, (2) Experiment on the change of oxidation rate using graphite density and data collection, (3) Measure the BET surface area of the graphite. The experiments were performed using H451 (Great Lakes Carbon Corporation) and IG-110 (Toyo Tanso Co., Ltd) graphite. The reason for the use of those graphite materials is because their chemical and mechanical characteristics are well identified by the previous investigations, and therefore it was convenient for us to access the published data, and to apply and validate our new methodologies. This paper presents preliminary results of compressive strength vs. burn-off and surface area density vs. burn-off, which can be used for the nuclear graphite selection for the NGNP.« less

  8. Effect of laryngoscopy on middle ear pressure during anaesthesia induction.

    PubMed

    Degerli, Semih; Acar, Baran; Sahap, Mehmet; Horasanlı, Eyup

    2013-01-01

    The procedure of laryngoscopic orotracheal intubation (LOTI) has many impacts on several parts of the body. But its effect on middle ear pressure (MEP) is not known well. The purpose of this study is to evaluate the MEP changes subsequent to insertion of endotracheal tube with laryngoscope. 44 patients were included in this study with a normal physical examination of ear, nose and throat. A standard general anaesthesia induction without any inhaler agent was performed to the all patients. The MEP measurements for both ears were applied under 1 minute; before induction (BI) and after intubation (AI) with a middle ear analyzer. Also hemodynamic parameters were recorded before induction and after intubation. Of the 44 patients were 25 women and 19 men with a 43.5±15.1 mean age. A statistically significant rise in MEP was seen in all patients subsequent to insertion of endotracheal tube (P<0.05). Mean right MEPs were BI: -9.5 and AI: 18.5 daPa. Also mean left MEPs were BI: -21.7 and AI: 29.1 daPa. The amount of increases in left and right MEPs were 50 daPa and 27 daPa, respectively. 20% increase in systolic blood pressure and 19% increase in diastolic blood pressure were determined after intubation. The mean heart rate was 76/min before intubation, whereas it was 102/min after intubation with a 34% increase. In this study bilateral significant increases in MEP were determined subsequent to LOTI. Possible factors affecting MEP may be auditory tube, size and type of the blades, drugs and face masking time. But on the other hand in our opinion cardiovascular and haemodynamic response to LOTI has the most impact over the middle ear mucosa with mucosal venous congestion.

  9. Transnasal endoscopy: no gagging no panic!

    PubMed Central

    Parker, Clare; Alexandridis, Estratios; Plevris, John; O'Hara, James; Panter, Simon

    2016-01-01

    Background Transnasal endoscopy (TNE) is performed with an ultrathin scope via the nasal passages and is increasingly used. This review covers the technical characteristics, tolerability, safety and acceptability of TNE and also diagnostic accuracy, use as a screening tool and therapeutic applications. It includes practical advice from an ear, nose, throat (ENT) specialist to optimise TNE practice, identify ENT pathology and manage complications. Methods A Medline search was performed using the terms “transnasal”, “ultrathin”, “small calibre”, “endoscopy”, “EGD” to identify relevant literature. Results There is increasing evidence that TNE is better tolerated than standard endoscopy as measured using visual analogue scales, and the main area of discomfort is nasal during insertion of the TN endoscope, which seems remediable with adequate topical anaesthesia. The diagnostic yield has been found to be similar for detection of Barrett's oesophagus, gastric cancer and GORD-associated diseases. There are some potential issues regarding the accuracy of TNE in detecting small early gastric malignant lesions, especially those in the proximal stomach. TNE is feasible and safe in a primary care population and is ideal for screening for upper gastrointestinal pathology. It has an advantage as a diagnostic tool in the elderly and those with multiple comorbidities due to fewer adverse effects on the cardiovascular system. It has significant advantages for therapeutic procedures, especially negotiating upper oesophageal strictures and insertion of nasoenteric feeding tubes. Conclusions TNE is well tolerated and a valuable diagnostic tool. Further evidence is required to establish its accuracy for the diagnosis of early and small gastric malignancies. There is an emerging role for TNE in therapeutic endoscopy, which needs further study. PMID:28839865

  10. Air-Q intubating laryngeal airway: A study of the second generation supraglottic airway device.

    PubMed

    Attarde, Viren Bhaskar; Kotekar, Nalini; Shetty, Sarika M

    2016-05-01

    Air-Q intubating laryngeal mask airway (ILA) is used as a supraglottic airway device and as a conduit for endotracheal intubation. This study aims to assess the efficacy of the Air-Q ILA regarding ease of insertion, adequacy of ventilation, rate of successful intubation, haemodynamic response and airway morbidity. Sixty patients presenting for elective surgery at our Medical College Hospital were selected. Following adequate premedication, baseline vital parameters, pulse rate and blood pressure were recorded. Air-Q size 3.5 for patients 50-70 kg and size 4.5 for 70-100 kg was selected. After achieving adequate intubating conditions, Air-Q ILA was introduced. Confirming adequate ventilation, appropriate sized endotracheal tube was advanced through the Air-Q blindly to intubate the trachea. Placement of the endotracheal tube in trachea was confirmed. Air-Q ILA was successfully inserted in 88.3% of patients in first attempt and 11.7% patients in second attempt. Ventilation was adequate in 100% of patients. Intubation was successful in 76.7% of patients with Air-Q ILA. 23.3% of patients were intubated by direct laryngoscopy following failure with two attempts using Air-Q ILA. Post-intubation the change in heart rate was statistically significant (P < 0.0001). 10% of patients were noted to have a sore throat and 5% of patients had mild airway trauma. Air-Q ILA is a reliable device as a supraglottic airway ensuring adequate ventilation as well as a conduit for endotracheal intubation. It benefits the patient by avoiding the stress of direct laryngoscopy and is also superior alternative device for use in a difficult airway.

  11. Systems and methods for forming defects on graphitic materials and curing radiation-damaged graphitic materials

    DOEpatents

    Ryu, Sunmin; Brus, Louis E.; Steigerwald, Michael L.; Liu, Haitao

    2012-09-25

    Systems and methods are disclosed herein for forming defects on graphitic materials. The methods for forming defects include applying a radiation reactive material on a graphitic material, irradiating the applied radiation reactive material to produce a reactive species, and permitting the reactive species to react with the graphitic material to form defects. Additionally, disclosed are methods for removing defects on graphitic materials.

  12. Speech recovery device

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

    Frankle, Christen M.

    2000-10-19

    There is provided an apparatus and method for assisting speech recovery in people with inability to speak due to aphasia, apraxia or another condition with similar effect. A hollow, rigid, thin-walled tube with semi-circular or semi-elliptical cut out shapes at each open end is positioned such that one end mates with the throat/voice box area of the neck of the assistor and the other end mates with the throat/voice box area of the assisted. The speaking person (assistor) makes sounds that produce standing wave vibrations at the same frequency in the vocal cords of the assisted person. Driving the assistedmore » person's vocal cords with the assisted person being able to hear the correct tone enables the assisted person to speak by simply amplifying the vibration of membranes in their throat.« less

  13. RADIATION SOURCE

    DOEpatents

    Gow, J.D.

    1961-06-27

    An improved version of a crossed electric and magnetic field plasma producing and containing device of the general character disclosed in U. S. Patent No. 2,967,943 is described. This device employs an annular magnet encased within an anode and a pair of cathodes respectively coaxially spaced from the opposite ends of the anode to establish crossed field electron trapping regions adjacent the ends of the anode. The trapping regions are communicably connected through the throat of the anode and the electric field negatively increases in opposite axial directions from the center of the throat. Electrons are trapped within the two trapping regions and throat to serve as a source of intense ionization to gas introduced thereto, the ions in copious quantities being attracted to the cathodes to bombard neutron productive targets dlsposed - thereat.

  14. Speech recovery device

    DOEpatents

    Frankle, Christen M.

    2004-04-20

    There is provided an apparatus and method for assisting speech recovery in people with inability to speak due to aphasia, apraxia or another condition with similar effect. A hollow, rigid, thin-walled tube with semi-circular or semi-elliptical cut out shapes at each open end is positioned such that one end mates with the throat/voice box area of the neck of the assistor and the other end mates with the throat/voice box area of the assisted. The speaking person (assistor) makes sounds that produce standing wave vibrations at the same frequency in the vocal cords of the assisted person. Driving the assisted person's vocal cords with the assisted person being able to hear the correct tone enables the assisted person to speak by simply amplifying the vibration of membranes in their throat.

  15. The influence of pore structure parameters on the digital core recovery degree

    NASA Astrophysics Data System (ADS)

    Xia, Huifen; Zhao, Ling; Sun, Yanyu; Yuan, Shi

    2017-05-01

    Constructing digital core in the research of water flooding or polymer flooding oil displacement efficiency has its unique advantage. Using mercury injection experiment measured pore throat size distribution frequency, coordination number measured by CT scanning method and imbibition displacement method is used to measure the wettability of the data, on the basis of considering pore throat ratio, wettability, using the principle of adaptive porosity, on the basis of fitting the permeability to complete the construction of digital core. The results show that the model of throat distribution is concentrated water flooding recovery degree is higher, and distribution is more decentralized model polymer flooding recovery degree is higher. Around the same number of PV in poly, coordination number model of water flooding and polymer flooding recovery degree is higher.

  16. AXISYMMETRIC, THROTTLEABLE NON-GIMBALLED ROCKET ENGINE

    NASA Technical Reports Server (NTRS)

    Sackheim, Robert L. (Inventor); Hutt, John J. (Inventor); Anderson, William E. (Inventor); Dressler, Gordon A. (Inventor)

    2005-01-01

    A rocket engine assembly is provided for a vertically launched rocket vehicle. A rocket engine housing of the assembly includes two or more combustion chambers each including an outlet end defining a sonic throat area. A propellant supply for the combustion chambers includes a throttling injector, associated with each of the combustion chambers and located opposite to sonic throat area, which injects the propellant into the associated combustion chamber. A modulator, which may form part of the injector, and which is controlled by a controller, modulates the flow rate of the propellant to the combustion chambers so that the chambers provide a vectorable net thrust. An expansion nozzle or body located downstream of the throat area provides expansion of the combustion gases produced by the combustion chambers so as to increase the net thrust.

  17. Design of a pulsed-mode fluidic pump using a venturi-like reverse flow diverter. [With no packing glands, mechanical seals or moving parts

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

    Smith, G.V.; Lewis, B.E.

    1987-02-01

    This report presents a design procedure for pulsed-mode, venturi-like reverse flow diverter (RFD) pumping systems. Design techniques are presented for systems in which the output line area is allowed to vary proportionally with the throat area of the RFD as well as situations in which the output line area is held constant. The results show that for cases in which the output line area is allowed to vary, an optimum RFD throat area exists for a given input pressure. For situations in which the output line area is held constant, the average output flow decreases in almost a linear fashionmore » with increasing RFD throat area. 6 refs., 8 figs.« less

  18. Dirac-Born-Infeld inflation using a one-parameter family of throat geometries

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

    Gmeiner, Florian; White, Chris D, E-mail: fgmeiner@nikhef.nl, E-mail: cwhite@nikhef.nl

    2008-02-15

    We demonstrate the possibility of examining cosmological signatures in the Dirac-Born-Infeld (DBI) inflation setup using the BGMPZ solution, a one-parameter family of geometries for the warped throat which interpolate between the Maldacena-Nunez and Klebanov-Strassler solutions. The warp factor is determined numerically and is subsequently used to calculate cosmological observables, including the scalar and tensor spectral indices, for a sample point in the parameter space. As one moves away from the Klebanov-Strassler (KS) solution for the throat, the warp factor is qualitatively different, which leads to a significant change for the observables, but also generically increases the non-Gaussianity of the models.more » We argue that the different models can potentially be differentiated by current and future experiments.« less

  19. A method for calculating a real-gas two-dimensional nozzle contour including the effects of gamma

    NASA Technical Reports Server (NTRS)

    Johnson, C. B.; Boney, L. R.

    1975-01-01

    A method for calculating two-dimensional inviscid nozzle contours for a real gas or an ideal gas by the method of characteristics is described. The method consists of a modification of an existing nozzle computer program. The ideal-gas nozzle contour can be calculated for any constant value of gamma. Two methods of calculating the center-line boundary values of the Mach number in the throat region are also presented. The use of these three methods of calculating the center-line Mach number distribution in the throat region can change the distance from the throat to the inflection point by a factor of 2.5. A user's guide is presented for input to the computer program for both the two-dimensional and axisymmetric nozzle contours.

  20. Nonsymmetric dynamical thin-shell wormhole in Robinson-Trautman class

    NASA Astrophysics Data System (ADS)

    Svítek, O.; Tahamtan, T.

    2018-02-01

    The thin-shell wormhole created using the Darmois-Israel formalism applied to Robinson-Trautman family of spacetimes is presented. The stress energy tensor created on the throat is interpreted in terms of two dust streams and it is shown that asymptotically this wormhole settles to the Schwarzschild wormhole with a throat located at the position of the horizon. This behavior shows a nonlinear stability (within the Robinson-Trautman class) of this spherically symmetric wormhole. The gravitational radiation emitted by the Robinson-Trautman wormhole during the transition to spherical symmetry is indistinguishable from that of the corresponding black hole Robinson-Trautman spacetime. Subsequently, we show that the higher-dimensional generalization of Robinson-Trautman geometry offers a possibility of constructing wormholes without the need to violate the energy conditions for matter induced on the throat.

  1. Capacitor with a composite carbon foam electrode

    DOEpatents

    Mayer, Steven T.; Pekala, Richard W.; Kaschmitter, James L.

    1999-01-01

    Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid partides being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy.

  2. Method for fabricating composite carbon foam

    DOEpatents

    Mayer, Steven T.; Pekala, Richard W.; Kaschmitter, James L.

    2001-01-01

    Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy.

  3. Capacitor with a composite carbon foam electrode

    DOEpatents

    Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

    1999-04-27

    Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

  4. Composite carbon foam electrode

    DOEpatents

    Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

    1997-05-06

    Carbon aerogels used as a binder for granulated materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

  5. Metal spray apparatus with a U-shaped electric inlet gas heater and a one-piece electric heater surrounding a nozzle

    DOEpatents

    Glovan, Ronald J.; Tierney, John C.; McLean, Leroy L.; Johnson, Lawrence L.; Verbael, David J.

    1995-01-01

    An electrically heated metal spray apparatus is provided with a supersonic nozzle. Molten metal is injected into a gas stream flowing through the nozzle under pressure. By varying the pressure of the injected metal, the droplet can be made in various selected sizes with each selected size having a high degree of size uniformity. A unique one piece graphite heater provides easily controlled uniformity of temperature in the nozzle and an attached tundish which holds the pressurized molten metal. A unique U-shaped gas heater provides extremely hot inlet gas temperatures to the nozzle. A particularly useful application of the spray apparatus is coating of threads of a fastener with a shape memory alloy. This permits a fastener to be easily inserted and removed but provides for a secure locking of the fastener in high temperature environments.

  6. Metal spray apparatus with a U-shaped electric inlet gas heater and a one-piece electric heater surrounding a nozzle

    DOEpatents

    Glovan, R.J.; Tierney, J.C.; McLean, L.L.; Johnson, L.L.; Verbael, D.J.

    1995-10-17

    An electrically heated metal spray apparatus is provided with a supersonic nozzle. Molten metal is injected into a gas stream flowing through the nozzle under pressure. By varying the pressure of the injected metal, the droplet can be made in various selected sizes with each selected size having a high degree of size uniformity. A unique one piece graphite heater provides easily controlled uniformity of temperature in the nozzle and an attached tundish which holds the pressurized molten metal. A unique U-shaped gas heater provides extremely hot inlet gas temperatures to the nozzle. A particularly useful application of the spray apparatus is coating of threads of a fastener with a shape memory alloy. This permits a fastener to be easily inserted and removed but provides for a secure locking of the fastener in high temperature environments. 12 figs.

  7. Initial Neutronics Analyses for HEU to LEU Fuel Conversion of the Transient Reactor Test Facility (TREAT) at the Idaho National Laboratory

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

    Kontogeorgakos, D.; Derstine, K.; Wright, A.

    2013-06-01

    The purpose of the TREAT reactor is to generate large transient neutron pulses in test samples without over-heating the core to simulate fuel assembly accident conditions. The power transients in the present HEU core are inherently self-limiting such that the core prevents itself from overheating even in the event of a reactivity insertion accident. The objective of this study was to support the assessment of the feasibility of the TREAT core conversion based on the present reactor performance metrics and the technical specifications of the HEU core. The LEU fuel assembly studied had the same overall design, materials (UO 2more » particles finely dispersed in graphite) and impurities content as the HEU fuel assembly. The Monte Carlo N–Particle code (MCNP) and the point kinetics code TREKIN were used in the analyses.« less

  8. Effect of graphite target power density on tribological properties of graphite-like carbon films

    NASA Astrophysics Data System (ADS)

    Dong, Dan; Jiang, Bailing; Li, Hongtao; Du, Yuzhou; Yang, Chao

    2018-05-01

    In order to improve the tribological performance, a series of graphite-like carbon (GLC) films with different graphite target power densities were prepared by magnetron sputtering. The valence bond and microstructure of films were characterized by AFM, TEM, XPS and Raman spectra. The variation of mechanical and tribological properties with graphite target power density was analyzed. The results showed that with the increase of graphite target power density, the deposition rate and the ratio of sp2 bond increased obviously. The hardness firstly increased and then decreased with the increase of graphite target power density, whilst the friction coefficient and the specific wear rate increased slightly after a decrease with the increasing graphite target power density. The friction coefficient and the specific wear rate were the lowest when the graphite target power density was 23.3 W/cm2.

  9. AGC 2 Irradiated Material Properties Analysis

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

    Rohrbaugh, David Thomas

    2017-05-01

    The Advanced Reactor Technologies Graphite Research and Development Program is conducting an extensive graphite irradiation experiment to provide data for licensing of a high temperature reactor (HTR) design. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor designs. , Nuclear graphite H 451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphite grades have been developed and are considered suitable candidates for new HTR reactor designs. To support the design and licensing of HTR core componentsmore » within a commercial reactor, a complete properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade, with a specific emphasis on data accounting for the life limiting effects of irradiation creep on key physical properties of the HTR candidate graphite grades. Further details on the research and development activities and associated rationale required to qualify nuclear grade graphite for use within the HTR are documented in the graphite technology research and development plan.« less

  10. AGC 2 Irradiation Creep Strain Data Analysis

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

    Windes, William E.; Rohrbaugh, David T.; Swank, W. David

    2016-08-01

    The Advanced Reactor Technologies Graphite Research and Development Program is conducting an extensive graphite irradiation experiment to provide data for licensing of a high temperature reactor (HTR) design. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor designs. Nuclear graphite H-451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphite grades have been developed and are considered suitable candidates for new HTR reactor designs. To support the design and licensing of HTR core components within amore » commercial reactor, a complete properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade, with a specific emphasis on data accounting for the life limiting effects of irradiation creep on key physical properties of the HTR candidate graphite grades. Further details on the research and development activities and associated rationale required to qualify nuclear grade graphite for use within the HTR are documented in the graphite technology research and development plan.« less

  11. Preparation, quantitative surface analysis, intercalation characteristics and industrial implications of low temperature expandable graphite

    NASA Astrophysics Data System (ADS)

    Peng, Tiefeng; Liu, Bin; Gao, Xuechao; Luo, Liqun; Sun, Hongjuan

    2018-06-01

    Expandable graphite is widely used as a new functional carbon material, especially as fire-retardant; however, its practical application is limited due to the high expansion temperature. In this work, preparation process of low temperature and highly expandable graphite was studied, using natural flake graphite as raw material and KMnO4/HClO4/NH4NO3 as oxidative intercalations. The structure, morphology, functional groups and thermal properties were characterized during expanding process by Fourier transform infrared spectroscopy (FTIR), Raman spectra, thermo-gravimetry differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), and scanning electron microscope (SEM). The analysis showed that by oxidation intercalation, some oxygen-containing groups were grafted on the edge and within the graphite layer. The intercalation reagent entered the graphite layer to increase the interlayer spacing. After expansion, the original flaky expandable graphite was completely transformed into worm-like expanded graphite. The order of graphite intercalation compounds (GICs) was proposed and determined to be 3 for the prepared expandable graphite, based on quantitative XRD peak analysis. Meanwhile, the detailed intercalation mechanisms were also proposed. The comprehensive investigation paved a benchmark for the industrial application of such sulfur-free expanded graphite.

  12. The impact of LDEF results on the space application of metal matrix composites

    NASA Technical Reports Server (NTRS)

    Steckel, Gary L.; Le, Tuyen D.

    1993-01-01

    Over 200 graphite/aluminum and graphite/magnesium composites were flown on the leading and trailing edges of LDEF on the Advanced Composites Experiment. The performance of these composites was evaluated by performing scanning electron microscopy and x-ray photoelectron spectroscopy of exposed surfaces, optical microscopy of cross sections, and on-orbit and postflight thermal expansion measurements. Graphite/aluminum and graphite/magnesium were found to be superior to graphite/polymer matrix composites in that they are inherently resistant to atomic oxygen and are less susceptible to thermal cycling induced microcracking. The surface foils on graphite/aluminum and graphite/magnesium protect the graphite fibers from atomic oxygen and from impact damage from small micrometeoroid or space debris particles. However, the surface foils were found to be susceptible to thermal fatigue cracking arising from contamination embrittlement, surface oxidation, or stress risers. Thus, the experiment reinforced requirements for carefully protecting these composites from prelaunch oxidation or corrosion, avoiding spacecraft contamination, and designing composite structures to minimize stress concentrations. On-orbit strain measurements demonstrated the importance of through-thickness thermal conductivity in composites to minimize thermal distortions arising from thermal gradients. Because of the high thermal conductivity of aluminum, thermal distortions were greatly reduced in the LDEF thermal environment for graphite/aluminum as compared to graphite/magnesium and graphite/polymer composites. The thermal expansion behavior of graphite/aluminum and graphite/magnesium was stabilized by on-orbit thermal cycling in the same manner as observed in laboratory tests.

  13. Natural graphite demand and supply - Implications for electric vehicle battery requirements

    USGS Publications Warehouse

    Olson, Donald W.; Virta, Robert L.; Mahdavi, Mahbood; Sangine, Elizabeth S.; Fortier, Steven M.

    2016-01-01

    Electric vehicles have been promoted to reduce greenhouse gas emissions and lessen U.S. dependence on petroleum for transportation. Growth in U.S. sales of electric vehicles has been hindered by technical difficulties and the high cost of the lithium-ion batteries used to power many electric vehicles (more than 50% of the vehicle cost). Groundbreaking has begun for a lithium-ion battery factory in Nevada that, at capacity, could manufacture enough batteries to power 500,000 electric vehicles of various types and provide economies of scale to reduce the cost of batteries. Currently, primary synthetic graphite derived from petroleum coke is used in the anode of most lithium-ion batteries. An alternate may be the use of natural flake graphite, which would result in estimated graphite cost reductions of more than US$400 per vehicle at 2013 prices. Most natural flake graphite is sourced from China, the world's leading graphite producer. Sourcing natural flake graphite from deposits in North America could reduce raw material transportation costs and, given China's growing internal demand for flake graphite for its industries and ongoing environmental, labor, and mining issues, may ensure a more reliable and environmentally conscious supply of graphite. North America has flake graphite resources, and Canada is currently a producer, but most new mining projects in the United States require more than 10 yr to reach production, and demand could exceed supplies of flake graphite. Natural flake graphite may serve only to supplement synthetic graphite, at least for the short-term outlook.

  14. Five dimensional microstate geometries

    NASA Astrophysics Data System (ADS)

    Wang, Chih-Wei

    In this thesis, we discuss the possibility of exploring the statistical mechanics description of a black hole from the point view of supergravity. Specifically, we study five dimensional microstate geometries of a black hole or black ring. At first, we review the method to find the general three-charge BPS supergravity solutions proposed by Bena and Warner. By applying this method, we show the classical merger of a black ring and black hole on [Special characters omitted.] base space in general are irreversible. On the other hand, we review the solutions on ambi-polar Gibbons-Hawking (GH) base which are bubbled geometries. There are many possible microstate geometries among the bubbled geometries. Particularly, we show that a generic blob of GH points that satisfy certain conditions can be either microstate geometry of a black hole or black ring without horizon. Furthermore, using the result of the entropy analysis in classical merger as a guide, we show that one can have a merger of a black-hole blob and a black-ring blob or two black-ring blobs that corresponds to a classical irreversible merger. From the irreversible mergers, we find the scaling solutions and deep microstates which are microstate geometries of a black hole/ring with macroscopic horizon. These solutions have the same AdS throats as classical black holes/rings but instead of having infinite throats, the throat is smoothly capped off at a very large depth with some local structure at the bottom. For solutions that produced from U (1) × U (1) invariant merger, the depth of the throat is limited by flux quantization. The mass gap is related with the depth of this throat and we show the mass gap of these solutions roughly match with the mass gap of the typical conformal-field-theory (CFT) states. Therefore, based on AdS/CFT correspondence, they can be dual geometries of the typical CFT states that contribute to the entropy of a black hole/ring. On the other hand, we show that for the solutions produced from more general merger (without U (1) × U (1) invariance), the throat can be arbitrarily deep. This presents a puzzle from the point view of AdS/CFT correspondence. We propose that this puzzle may be solved by some quantization of the angle or promoting the flux vectors to quantum spins. Finally, we suggest some future directions of further study including the puzzle of arbitrary long AdS throat and a general coarse-graining picture of microstate geometries.

  15. Tungsten erosion by unipolar arcing in DIII-D

    NASA Astrophysics Data System (ADS)

    Bykov, I.; Chrobak, C. P.; Abrams, T.; Rudakov, D. L.; Unterberg, E. A.; Wampler, W. R.; Hollmann, E. M.; Moyer, R. A.; Boedo, J. A.; Stahl, B.; Hinson, E. T.; Yu, J. H.; Lasnier, C. J.; Makowski, M.; McLean, A. G.

    2017-12-01

    Unipolar arcing was an important mechanism of metal surface erosion during the recently conducted Metal Rings Campaign in DIII-D when two toroidally continuous tile rings with 5 cm wide W-coated TZM inserts were installed in graphite tiles in the lower divertor, one on the floor and one on the shelf. Most of the arc damage occurred on the shelf ring. The total amount of W removed by arcing from the affected ˜4% of the shelf ring area was estimated ˜0.8 × 1021 at., about half of the total amount of W eroded and redeposited outside the inserts (1.8 ± 0.9)×1021 at. The rings were exposed for a total of ˜480 discharges, an equivalent of plasma time on W surfaces (with {{I}}{{p}}> 0.5 MA) ˜103 s. Arcing was monitored in situ with WI (400.9 nm) filtered camera and photomultipliers and showed that: (i) arcing only occurred during ELMs and disruptions, (ii) arcing rate was much lower on the floor than on the shelf ring, and (iii) arcing had a low cut off power flux density about 2 MW m-2. About half of arc tracks had large {10}\\circ pitch angle and probably were produced during disruptions. Such tracks were only found on the shelf. Moderate toroidal variation of the arc track density and W erosion with nearly n = 1 pattern has been measured.

  16. Treatment of irradiated graphite from French Bugey reactor

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

    Stevens, Howard; Laurent, Gerard

    In 2008, following the general French plan for nuclear waste management, Electricite de France attempted to find for irradiated graphite an alternative solution to direct storage at the low-activity long-life storage center in France managed by the national agency for wastes (ANDRA). EDF management requested that its engineering arm, EDF CIDEN, study the graphite treatment alternatives to direct storage. In mid-2008, this study revealed the potential advantage for EDF to use a steam reforming process known as Thermal Organic Reduction, 'THOR' (owned by Studsvik, Inc., USA), to treat or destroy the graphite matrix and limit the quantity of secondary wastemore » to be stored. In late 2009, EDF began a test program with Studsvik to determine if the THOR steam reforming process could be used to destroy the graphite. The program also sought to determine if the graphite could be treated to release the bulk of activity while minimizing the gasification of the bulk mass of the graphite. In October 2009, tests with non-irradiated graphite were completed and demonstrated destruction of a graphite matrix by the THOR process at satisfactory rates. After gasifying the graphite, focus shifted to the effect of roasting graphite at high temperatures in inert gases with low concentrations of oxidizing gases to preferentially remove volatile radionuclides while minimizing the graphite mass loss to 5%. A radioactive graphite sleeve was imported from France to the US for these tests. Completed in April 2010, 'Phase I' of testing showed that the process removed >99% of H-3 and 46% of C-14 with <6% mass loss. Completed in September 2011, 'Phase II' testing achieved increased removals as high as 80% C-14. During Phase II, it was also discovered that roasting in a reducing atmosphere helped to limit the oxidation of the graphite. Future work seeks to explore the effects of reducing gases to limit the bulk oxidation of graphite. If the graphite could be decontaminated of long-lived radionuclides up to 95% for C-14 while minimizing mass loss to <5%, this would minimize the volume of any secondary waste streams and potentially lower the waste class of the larger bulk of graphite. Alternatively, if up to 95% decontamination of C-14 is achieved, the graphite may be completely gasified which could result in lower disposal. (authors)« less

  17. Coal-Sizing Auger

    NASA Technical Reports Server (NTRS)

    Lewis, E. V.

    1985-01-01

    Aft end of auger, like forward, face-piercing end, equipped with hard cutting bits such as diamonds. As auger breaks face, pulls broken coal lumps into jaws and forces them into hardened throat section. There, cutting bits chew up lumps: Clearance between throat and auger shaft sets maximum size for coal particles that pass through. Auger motion pushes coal particles into mixing chamber, where paddles combine them with water.

  18. Erosive-throat with rash (scarlet fever), an investigation on its brief history.

    PubMed

    Yu, Y

    1998-07-01

    Being a kind of epidemic contagious disease in modern time, erosive-throat with rash was a fatal disease causing numerous victims. High attention was paid to by traditional medical professionals through various fields, theoretical and clinical. A correct conclusion was reached claiming that TCM did make contributions to its prevention and treatment before effective treatment in western medicine appeared in China.

  19. Streamline coal slurry letdown valve

    DOEpatents

    Platt, Robert J.; Shadbolt, Edward A.

    1983-01-01

    A streamlined coal slurry letdown valve is featured which has a two-piece throat comprised of a seat and seat retainer. The two-piece design allows for easy assembly and disassembly of the valve. A novel cage holds the two-piece throat together during the high pressure letdown. The coal slurry letdown valve has long operating life as a result of its streamlined and erosion-resistance surfaces.

  20. Streamline coal slurry letdown valve

    DOEpatents

    Platt, R.J.; Shadbolt, E.A.

    1983-11-08

    A streamlined coal slurry letdown valve is featured which has a two-piece throat comprised of a seat and seat retainer. The two-piece design allows for easy assembly and disassembly of the valve. A novel cage holds the two-piece throat together during the high pressure letdown. The coal slurry letdown valve has long operating life as a result of its streamlined and erosion-resistance surfaces. 5 figs.

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