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Sample records for injection stretch blow

  1. Effect of Biaxial Stretching at Temperatures and Strain Histories Comparable to Injection Stretch Blow Moulding on Tensile Modulus for Polyethylene Terephthalate (PET)

    NASA Astrophysics Data System (ADS)

    Tan, C. W.; Menary, G. H.; Harkin-Jones, E. M. A.; Armstrong, C. G.; Martin, P. J.

    2007-04-01

    This study is particularly relevant to the injection stretch blow moulding (ISBM) process where PET material is typically biaxially stretched to form bottles for the water and carbonated soft drinks industry. The aim of this paper is to investigate the effect of biaxial stretching on the mechanical properties of Polyethylene Terephthalate (PET) using a custom built biaxial testing machine. An initially amorphous PET sample was prepared via injection moulding to form a square sample (76mm × 76mm) suitable for stretching on the machine. This sample was then subjected to a series of biaxial tests (simultaneous and sequential) within a temperature range between 85°C and 110 °C, strain rates in the range of 1s-1 to 32s-1 and stretch ratios in the range of 1.5 to 3. Specimens were subsequently cut from the biaxial stretched sheets and used to measure the tensile modulus. Results showed that there is almost no effect found for strain rate and temperature on modulus development whilst stretch ratio and mode of deformation played the most important role on modulus development on PET under biaxial deformation.

  2. Modeling the Constitutive Behaviour of PET for Stretch Blow Moulding

    NASA Astrophysics Data System (ADS)

    Yan, S. Y.; Menary, G.

    2011-05-01

    There are a substantial amount of constitutive models that have been developed to capture the finite deformation behavior of polymers for forming simulations. Most of these models have been used to capture the behavior in uniaxial and simultaneous biaxial modes of deformation. However, very few have attempted to model the sequential biaxial deformation behavior which is more appropriate for the stretch blow moulding process. The aim of this work is to develop a model for PET to successfully capture the sequential stress-strain behavior as a function of temperature and strain rate, thus making it suitable for use in simulations of stretch blow moulding. Biaxial test data has been generated at temperatures and strain rates appropriate for stretch blow moulding and a model developed by Buckley et al. has been implemented within the commercial finite element package Abaqus/Explicit. In parallel, an efficient automatic curve fitting procedure has been developed to enable the material parameters to be easily found from biaxial test data. The results show that the Buckley model can predict the stress response of equibiaxial deformation well, but cannot predict the sequential biaxial deformation.

  3. Method for the evaluation of stretch blow molding simulations with free blow trials

    NASA Astrophysics Data System (ADS)

    Zimmer, Johannes; Stommel, Markus

    2013-12-01

    Finite-Element (FE) simulations are a valuable tool to support the analysis and optimization of production processes. In order to achieve realistic simulation results, a consistent simulation set-up followed by an evaluation through experiments is crucial. Stretch Blow Molding (SBM) is a commonly applied forming method to produce thin walled bottles. Polyethylene terephthalate (PET) preforms are biaxially stretched into a closed cavity to form a bottle. In this process the thermo-mechanical material behavior during forming greatly influences the performance of the end product and consequently plays a key role for a reliable process simulation. To ensure a realistic material representation in the simulation model, an adequate material model is calibrated with stress-strain curves from biaxial tests. Thin PET-sheets are stretched under defined temperatures and strain rates. These representative experiments include process simplifications regarding geometry, heating and deformation parameters. Therefore, an evaluation step subsequent to the simulation set-up is inevitable. This paper presents a method for extracting temperature dependent stress-strain-curves from experiments close to the production process which enables the crucial evaluation of a process simulation. In the SBM process, the wall thickness distribution of the bottle refers to the preform deformation over time but does not fully define the thermo-mechanical material behavior. In the presented method, PET-preforms receive thermal treatment with Infrared (IR)-heaters from an SBM-machine and are subsequently inflated into free air (free-blow-trial). An IR-camera is used to obtain the temperature distribution on the preform immediately before blowing. Two high speed cameras are synchronized with a pressure sensor to consequently calculate reliable stress-strain curves at any point on the preform surface. These data is finally compared to results from FE-simulations of the free blow trials.

  4. Simulation of the Two Stages Stretch-Blow Molding Process: Infrared Heating and Blowing Modeling

    SciTech Connect

    Bordival, M.; Schmidt, F. M.; Le Maoult, Y.; Velay, V.

    2007-05-17

    In the Stretch-Blow Molding (SBM) process, the temperature distribution of the reheated perform affects drastically the blowing kinematic, the bottle thickness distribution, as well as the orientation induced by stretching. Consequently, mechanical and optical properties of the final bottle are closely related to heating conditions. In order to predict the 3D temperature distribution of a rotating preform, numerical software using control-volume method has been developed. Since PET behaves like a semi-transparent medium, the radiative flux absorption was computed using Beer Lambert law. In a second step, 2D axi-symmetric simulations of the SBM have been developed using the finite element package ABAQUS registered . Temperature profiles through the preform wall thickness and along its length were computed and applied as initial condition. Air pressure inside the preform was not considered as an input variable, but was automatically computed using a thermodynamic model. The heat transfer coefficient applied between the mold and the polymer was also measured. Finally, the G'sell law was used for modeling PET behavior. For both heating and blowing stage simulations, a good agreement has been observed with experimental measurements. This work is part of the European project ''APT{sub P}ACK'' (Advanced knowledge of Polymer deformation for Tomorrow's PACKaging)

  5. Simulation of the Two Stages Stretch-Blow Molding Process: Infrared Heating and Blowing Modeling

    NASA Astrophysics Data System (ADS)

    Bordival, M.; Schmidt, F. M.; Le Maoult, Y.; Velay, V.

    2007-05-01

    In the Stretch-Blow Molding (SBM) process, the temperature distribution of the reheated perform affects drastically the blowing kinematic, the bottle thickness distribution, as well as the orientation induced by stretching. Consequently, mechanical and optical properties of the final bottle are closely related to heating conditions. In order to predict the 3D temperature distribution of a rotating preform, numerical software using control-volume method has been developed. Since PET behaves like a semi-transparent medium, the radiative flux absorption was computed using Beer Lambert law. In a second step, 2D axi-symmetric simulations of the SBM have been developed using the finite element package ABAQUS®. Temperature profiles through the preform wall thickness and along its length were computed and applied as initial condition. Air pressure inside the preform was not considered as an input variable, but was automatically computed using a thermodynamic model. The heat transfer coefficient applied between the mold and the polymer was also measured. Finally, the G'sell law was used for modeling PET behavior. For both heating and blowing stage simulations, a good agreement has been observed with experimental measurements. This work is part of the European project "APT_PACK" (Advanced knowledge of Polymer deformation for Tomorrow's PACKaging).

  6. Microstructural evolution of PET under stretching and during stretch blow moulding

    NASA Astrophysics Data System (ADS)

    Picard, Martine; Billon, Noëlle

    2007-04-01

    Strain induced crystallisation of PET designed for stretch blow molding is studied combining well-controlled tensile tests and free blowing on a stretch blow prototype. Microstructure evolution is followed by WAXS and SAXS. Observations on blown parts clearly show that the microstructure can differ along the bottle and from processing conditions to another. Difference can be observed on crystalline orientation, periodic arrangement at the level of lamellae and long period. Range of long period, 8.5 to 13 nm is in agreement with literature. In certain case lamellar organisation disappears. Despite of high level of strain and evidence for strain hardening to occur during blowing no perfect crystalline pattern is observed, except in very thick zones. Interrupted tensile tests followed by quenching demonstrates that strain hardening is not correlated to prefect crystallisation. Microstructure clearly depends on the three parameters: temperature, strain rate and strain. It is concluded that strain hardening is mainly controlled by first stages of crystallisation and that actual crystallisation occurs during a following relaxation step. This later is then highly dependent upon cooling step.

  7. Finite Element Modeling of Reheat Stretch Blow Molding of PET

    NASA Astrophysics Data System (ADS)

    Krishnan, Dwarak; Dupaix, Rebecca B.

    2004-06-01

    Poly (ethylene terephthalate) or PET is a polymer used as a packaging material for consumer products such as beverages, food or other liquids, and in other applications including drawn fibers and stretched films. Key features that make it widely used are its transparency, dimensional stability, gas impermeability, impact resistance, and high stiffness and strength in certain preferential directions. These commercially useful properties arise from the fact that PET crystallizes upon deformation above the glass transition temperature. Additionally, this strain-induced crystallization causes the deformation behavior of PET to be highly sensitive to processing conditions. It is thus crucial for engineers to be able to predict its performance at various process temperatures, strain rates and strain states so as to optimize the manufacturing process. In addressing these issues; a finite element analysis of the reheat blow molding process with PET has been carried out using ABAQUS. The simulation employed a constitutive model for PET developed by Dupaix and Boyce et al.. The model includes the combined effects of molecular orientation and strain-induced crystallization on strain hardening when the material is deformed above the glass transition temperature. The simulated bottles were also compared with actual blow molded bottles to evaluate the validity of the simulation.

  8. Thermo-mechanical simulation of liquid-supported stretch blow molding

    SciTech Connect

    Zimmer, J.; Stommel, M.

    2015-05-22

    Stretch blow molding is the well-established plastics forming method to produce Polyehtylene therephtalate (PET) bottles. An injection molded preform is heated up above the PET glass transition temperature (Tg∼85°C) and subsequently inflated by pressurized air into a closed cavity. In the follow-up filling process, the resulting bottle is filled with the final product. A recently developed modification of the process combines the blowing and filling stages by directly using the final liquid product to inflate the preform. In a previously published paper, a mechanical simulation and successful evaluation of this liquid-driven stretch blow molding process was presented. In this way, a realistic process parameter dependent simulation of the preform deformation throughout the forming process was enabled, whereas the preform temperature evolution during forming was neglected. However, the formability of the preform is highly reduced when the temperature sinks below Tg during forming. Experimental investigations show temperature-induced failure cases due to the fast heat transfer between hot preform and cold liquid. Therefore, in this paper, a process dependent simulation of the temperature evolution during processing to avoid preform failure is presented. For this purpose, the previously developed mechanical model is used to extract the time dependent thickness evolution. This information serves as input for the heat transfer simulation. The required material parameters are calibrated from preform cooling experiments recorded with an infrared-camera. Furthermore, the high deformation ratios during processing lead to strain induced crystallization. This exothermal reaction is included into the simulation by extracting data from preform measurements at different stages of deformation via Differential Scanning Calorimetry (DSC). Finally, the thermal simulation model is evaluated by free forming experiments, recorded by a high-speed infrared camera.

  9. Thermo-mechanical simulation of liquid-supported stretch blow molding

    NASA Astrophysics Data System (ADS)

    Zimmer, J.; Stommel, M.

    2015-05-01

    Stretch blow molding is the well-established plastics forming method to produce Polyehtylene therephtalate (PET) bottles. An injection molded preform is heated up above the PET glass transition temperature (Tg˜85°C) and subsequently inflated by pressurized air into a closed cavity. In the follow-up filling process, the resulting bottle is filled with the final product. A recently developed modification of the process combines the blowing and filling stages by directly using the final liquid product to inflate the preform. In a previously published paper, a mechanical simulation and successful evaluation of this liquid-driven stretch blow molding process was presented. In this way, a realistic process parameter dependent simulation of the preform deformation throughout the forming process was enabled, whereas the preform temperature evolution during forming was neglected. However, the formability of the preform is highly reduced when the temperature sinks below Tg during forming. Experimental investigations show temperature-induced failure cases due to the fast heat transfer between hot preform and cold liquid. Therefore, in this paper, a process dependent simulation of the temperature evolution during processing to avoid preform failure is presented. For this purpose, the previously developed mechanical model is used to extract the time dependent thickness evolution. This information serves as input for the heat transfer simulation. The required material parameters are calibrated from preform cooling experiments recorded with an infrared-camera. Furthermore, the high deformation ratios during processing lead to strain induced crystallization. This exothermal reaction is included into the simulation by extracting data from preform measurements at different stages of deformation via Differential Scanning Calorimetry (DSC). Finally, the thermal simulation model is evaluated by free forming experiments, recorded by a high-speed infrared camera.

  10. FE-Analysis of Stretch-Blow Moulded Bottles Using an Integrative Process Simulation

    NASA Astrophysics Data System (ADS)

    Hopmann, C.; Michaeli, W.; Rasche, S.

    2011-05-01

    The two-stage stretch-blow moulding process has been established for the large scale production of high quality PET containers with excellent mechanical and optical properties. The total production costs of a bottle are significantly caused by the material costs. Due to this dominant share of the bottle material, the PET industry is interested in reducing the total production costs by an optimised material efficiency. However, a reduced material inventory means decreasing wall thicknesses and therewith a reduction of the bottle properties (e.g. mechanical properties, barrier properties). Therefore, there is often a trade-off between a minimal bottle weight and adequate properties of the bottle. In order to achieve the objectives Computer Aided Engineering (CAE) techniques can assist the designer of new stretch-blow moulded containers. Hence, tools such as the process simulation and the structural analysis have become important in the blow moulding sector. The Institute of Plastics Processing (IKV) at RWTH Aachen University, Germany, has developed an integrative three-dimensional process simulation which models the complete path of a preform through a stretch-blow moulding machine. At first, the reheating of the preform is calculated by a thermal simulation. Afterwards, the inflation of the preform to a bottle is calculated by finite element analysis (FEA). The results of this step are e.g. the local wall thickness distribution and the local biaxial stretch ratios. Not only the material distribution but also the material properties that result from the deformation history of the polymer have significant influence on the bottle properties. Therefore, a correlation between the material properties and stretch ratios is considered in an integrative simulation approach developed at IKV. The results of the process simulation (wall thickness, stretch ratios) are transferred to a further simulation program and mapped on the bottles FE mesh. This approach allows a local

  11. Simulative design and process optimization of the two-stage stretch-blow molding process

    NASA Astrophysics Data System (ADS)

    Hopmann, Ch.; Rasche, S.; Windeck, C.

    2015-05-01

    The total production costs of PET bottles are significantly affected by the costs of raw material. Approximately 70 % of the total costs are spent for the raw material. Therefore, stretch-blow molding industry intends to reduce the total production costs by an optimized material efficiency. However, there is often a trade-off between an optimized material efficiency and required product properties. Due to a multitude of complex boundary conditions, the design process of new stretch-blow molded products is still a challenging task and is often based on empirical knowledge. Application of current CAE-tools supports the design process by reducing development time and costs. This paper describes an approach to determine optimized preform geometry and corresponding process parameters iteratively. The wall thickness distribution and the local stretch ratios of the blown bottle are calculated in a three-dimensional process simulation. Thereby, the wall thickness distribution is correlated with an objective function and preform geometry as well as process parameters are varied by an optimization algorithm. Taking into account the correlation between material usage, process history and resulting product properties, integrative coupled simulation steps, e.g. structural analyses or barrier simulations, are performed. The approach is applied on a 0.5 liter PET bottle of Krones AG, Neutraubling, Germany. The investigations point out that the design process can be supported by applying this simulative optimization approach. In an optimization study the total bottle weight is reduced from 18.5 g to 15.5 g. The validation of the computed results is in progress.

  12. Simulative design and process optimization of the two-stage stretch-blow molding process

    SciTech Connect

    Hopmann, Ch.; Rasche, S.; Windeck, C.

    2015-05-22

    The total production costs of PET bottles are significantly affected by the costs of raw material. Approximately 70 % of the total costs are spent for the raw material. Therefore, stretch-blow molding industry intends to reduce the total production costs by an optimized material efficiency. However, there is often a trade-off between an optimized material efficiency and required product properties. Due to a multitude of complex boundary conditions, the design process of new stretch-blow molded products is still a challenging task and is often based on empirical knowledge. Application of current CAE-tools supports the design process by reducing development time and costs. This paper describes an approach to determine optimized preform geometry and corresponding process parameters iteratively. The wall thickness distribution and the local stretch ratios of the blown bottle are calculated in a three-dimensional process simulation. Thereby, the wall thickness distribution is correlated with an objective function and preform geometry as well as process parameters are varied by an optimization algorithm. Taking into account the correlation between material usage, process history and resulting product properties, integrative coupled simulation steps, e.g. structural analyses or barrier simulations, are performed. The approach is applied on a 0.5 liter PET bottle of Krones AG, Neutraubling, Germany. The investigations point out that the design process can be supported by applying this simulative optimization approach. In an optimization study the total bottle weight is reduced from 18.5 g to 15.5 g. The validation of the computed results is in progress.

  13. Measurement Of Thermal Contact Resistance Between The Mold And The Polymer For The Stretch-blow Molding Process

    NASA Astrophysics Data System (ADS)

    Bordival, M.; Schmidt, F. M.; Le Maoult, Y.; Coment, E.

    2007-04-01

    In the stretch-blow molding process, the heat transfer between the polymer and the mold is of prime interest. Although the time of contact is very short (typically around 0.5 s), the heat transfer affects the mechanical properties of the bottle, and the quality of final parts. In order to model heat transfers at the interface, a classical approach — generally adopted in numerical softwares — is to impose the heat flux density boundary condition thanks to a parameter called Thermal Contact Resistance (TCR). This paper focuses on describing the experimental method developed in order to measure evolution of this thermal parameter (TCR) versus time, as well as results obtained on the CROMeP blowing machine. In this study, a mold has been instrumented with two different sensors. The first probe allows to estimate the heat flux density and temperature at the mold surface temperature, using a linear inverse heat condution problem (Function Specification Method). The second device is used to measure the surface temperature of the PET during the blowing. This measurement is non intrusive, and can be applied within an industrial environment during the blowing step. In addition, air pressure inside the preform is also measured during the blowing. This work is part of the European project "APT_PACK" (Advanced knowledge of Polymer deformation for Tomorrow's PACKaging).

  14. Foam injection molding of thermoplastic elastomers: Blowing agents, foaming process and characterization of structural foams

    NASA Astrophysics Data System (ADS)

    Ries, S.; Spoerrer, A.; Altstaedt, V.

    2014-05-01

    Polymer foams play an important role caused by the steadily increasing demand to light weight design. In case of soft polymers, like thermoplastic elastomers (TPE), the haptic feeling of the surface is affected by the inner foam structure. Foam injection molding of TPEs leads to so called structural foam, consisting of two compact skin layers and a cellular core. The properties of soft structural foams like soft-touch, elastic and plastic behavior are affected by the resulting foam structure, e.g. thickness of the compact skins and the foam core or density. This inner structure can considerably be influenced by different processing parameters and the chosen blowing agent. This paper is focused on the selection and characterization of suitable blowing agents for foam injection molding of a TPE-blend. The aim was a high density reduction and a decent inner structure. Therefore DSC and TGA measurements were performed on different blowing agents to find out which one is appropriate for the used TPE. Moreover a new analyzing method for the description of processing characteristics by temperature dependent expansion measurements was developed. After choosing suitable blowing agents structural foams were molded with different types of blowing agents and combinations and with the breathing mold technology in order to get lower densities. The foam structure was analyzed to show the influence of the different blowing agents and combinations. Finally compression tests were performed to estimate the influence of the used blowing agent and the density reduction on the compression modulus.

  15. The Use of Elasto-Visco-Plastic Material Model Coupled with Pressure-Volume Thermodynamic Relationship to Simulate the Stretch Blow Molding of Polyethylene Terephthalate

    NASA Astrophysics Data System (ADS)

    Mir, H.; Benrabah, Z.; Thibault, F.

    2007-05-01

    The use of polyethylene terephthalate (PET) in the stretch blow molding process presents several challenging issues due to various processing parameters and complex behavior of the material, which is both temperature and strain-rate dependent. In this paper, we generalize the G'Sell-Jonas law in 3D to model and simulate the elasto-visco-plastic (EVP) behavior of PET, taking into account strain-hardening and strain-softening. It is observed that the internal pressure (inside the preform) is significantly different from the nominal pressure (imposed in the blowing device upstream) since the internal pressure and the enclosed volume of the preform are fully coupled. In order to accurately simulate this phenomenon, a thermodynamic model was used to characterize the pressure-volume relationship (PVR). The predicted pressure evolution is thus more realistic when imposing only the machine power of the blowing device (air compressor or vacuum pump). Mechanical and temperature equilibrium equations are fully nonlinear and solved separately with implicit schemes on the current deformed configuration, which is updated at each time step. Biaxial characterization tests were used to determine the model parameters in order to simulate the stretch blow molding process using the pressure-volume thermodynamic relationship. To validate this model, thickness predictions for three industrial cases will be presented and compared to experimental measurements.

  16. Foam injection molding of poly(lactic acid) with physical blowing agents

    NASA Astrophysics Data System (ADS)

    Pantani, R.; Sorrentino, A.; Volpe, V.; Titomanlio, G.

    2014-05-01

    Foam injection molding uses environmental friendly blowing agents under high pressure and temperature to produce parts having a cellular core and a compact solid skin (the so-called "structural foam"). The addition of a supercritical gas reduces the part weight and at the same time improves some physical properties of the material through the promotion of a faster crystallization; it also leads to the reduction of both the viscosity and the glass transition temperature of the polymer melt, which therefore can be injection molded adopting lower temperatures and pressures. These aspects are of extreme interest for biodegradable polymers, which often present a very narrow processing window, with the suitable processing temperatures close to the degradation conditions. In this work, foam injection molding was carried out by an instrumented molding machine, able to measure the pressure evolution in different positions along the flow-path. The material adopted was a biodegradable polymer, namely the Poly(lactic acid), PLA. The effect of a physical blowing agent (PBA) on the viscosity was measured. The density reduction and the morphology of parts obtained by different molding conditions was assessed.

  17. Injection of new psychoactive substance snow blow associated with recently acquired HIV infections among homeless people who inject drugs in Dublin, Ireland, 2015.

    PubMed

    Giese, Coralie; Igoe, Derval; Gibbons, Zorina; Hurley, Caroline; Stokes, Siobhan; McNamara, Sinead; Ennis, Orla; O'Donnell, Kate; Keenan, Eamon; De Gascun, Cillian; Lyons, Fiona; Ward, Mary; Danis, Kostas; Glynn, Ronan; Waters, Allison; Fitzgerald, Margaret

    2015-01-01

    In February 2015, an outbreak of recently acquired HIV infections among people who inject drugs (PWID) was identified in Dublin, following similar outbreaks in Greece and Romania in 2011. We compared drug and risk behaviours among 15 HIV cases and 39 controls. Injecting a synthetic cathinone, snow blow, was associated with recent HIV infection (AOR: 49; p=0.003). Prevention and control efforts are underway among PWID in Dublin, but may also be needed elsewhere in Europe. PMID:26537764

  18. Effects of bulk flow pulsations on film cooling from different length injection holes at different blowing ratios

    SciTech Connect

    Seo, H.J.; Lee, J.S.; Ligrani, P.M.

    1999-07-01

    Bulk flow pulsations in the form of sinusoidal variations of velocity and static pressure at injectant Strouhal numbers from 0.8 to 10.0 are investigated as they affect film cooling from a single row of simple angle holes. Similar flow variations are produced by potential flow interactions and passing shock waves near turbine surfaces in gas turbine engines. Time-averaged temperature distributions, phase-averaged temperature distributions, adiabatic film cooling effectiveness values, and iso-energetic Stranton numbers show that important alterations to film cooling protection occur as pulsation frequency, coolant Strouhal number, blowing ratio, and nondimensional injection hole length are changed. Overall, the pulsations affect film performance and behavior more significantly both as L/D decreases, and as blowing ratio decreases.

  19. Numerical Solution for the Effect of Suction or Injection on Flow of Nanofluids Past a Stretching Sheet

    NASA Astrophysics Data System (ADS)

    Abd Elazem, Nader Y.

    2016-06-01

    The flow of nanofluids past a stretching sheet has attracted much attention owing to its wide applications in industry and engineering. Numerical solution has been discussed in this article for studying the effect of suction (or injection) on flow of nanofluids past a stretching sheet. The numerical results carried out using Chebyshev collocation method (ChCM). Useful results for temperature profile, concentration profile, reduced Nusselt number, and reduced Sherwood number are discussed in tabular and graphical forms. It was also demonstrated that both temperature and concentration profiles decrease by an increase from injection to suction. Moreover, the numerical results show that the temperature profiles decrease at high values of Prandtl number Pr. Finally, the present results showed that the reduced Nusselt number is a decreasing function, whereas the reduced Sherwood number is an increasing function at fixed values of Prandtl number Pr, Lewis number Le and suction (or injection) parameter s for variation of Brownian motion parameter Nb, and thermophoresis parameter Nt.

  20. Magnetohydrodynamic stagnation point flow and heat transfer in a nanofluid towards a stretching sheet with suction/injection

    NASA Astrophysics Data System (ADS)

    Zaimi, Khairy; Bakar, Nor Ashikin Abu

    2015-05-01

    This paper deals with the magnetohydrodynamic (MHD) stagnation point flow and heat transfer towards a permeable stretching sheet in a nanofluid. By using a similarity transformation, the governing equations of fluid flow are reduced into ordinary differential equation, which are then solved numerically using a shooting method. The effects of suction/injection parameter on the velocity, temperature and concentration profiles and heat transfer characteristics are obtained and graphically presented. It is found that skin friction coefficient and the local Nusselt number increase with suction, while it acts in opposite manner with injection.

  1. Comparison between Steroid Injection and Stretching Exercise on the Scalene of Patients with Upper Extremity Paresthesia: Randomized Cross-Over Study

    PubMed Central

    Kim, Yong Wook; Yoon, Seo Yeon; Park, Yongbum; Chang, Won Hyuk

    2016-01-01

    Purpose To compare the therapeutic effects on upper extremity paresthesia of intra-muscular steroid injections into the scalene muscle with those of stretching exercise only. Materials and Methods Twenty patients with upper extremity paresthesia who met the criteria were recruited to participate in this single-blind, crossover study. Fourteen of 20 patients were female. The average age was 45.0±10.5 years and duration of symptom was 12.2±8.7 months. Each participant completed one injection and daily exercise program for 2 weeks. After randomization, half of all patients received ultrasound-guided injection of scalene muscles before exercise, while the other was invested for the other patients. Results After two weeks, there was a significant decrease of the visual analog scale score of treatment effect compared with baseline in both groups (6.90 to 2.85 after injection and 5.65 to 4.05 after stretching exercise, p<0.01). However, injection resulted in greater improvements than stretching exercise (p<0.01). The number of patients with successful treatment, defined as >50% reduction in post-treatment visual analog scale, was 18 of 20 (90.0%) after injection, compared to 5 of 20 (25.0%) after stretching exercise. There were no cases of unintended brachial plexus block after injection. Conclusion Ultrasound-guided steroid injection or stretching exercise of scalene muscles led to reduced upper extremity paresthesia in patients who present with localized tenderness in the scalene muscle without electrodiagnostic test abnormalities, although injection treatment resulted in more improvements. The results suggest that symptoms relief might result from injection into the muscle alone not related to blockade of the brachial plexus. PMID:26847305

  2. Blowing Polymer Bubbles in an Acoustic Levitator

    NASA Technical Reports Server (NTRS)

    Lee, M. C.

    1985-01-01

    In new manufacturing process, small gas-filled polymer shells made by injecting gas directly into acoustically levitated prepolymer drops. New process allows sufficient time for precise control of shell geometry. Applications foreseen in fabrication of deuterium/tritium-filled fusion targets and in pharmaceutical coatings. New process also useful in glass blowing and blow molding.

  3. The analysis of the suction/injection on the MHD Maxwell fluid past a stretching plate in the presence of nanoparticles by Lie group method

    NASA Astrophysics Data System (ADS)

    Cao, Limei; Si, Xinhui; Zheng, Liancun; Pang, Huihui

    2015-01-01

    In this paper, the magnetohydrodynamic (MHD) Maxwell fluid past a stretching plate with suction/ injection in the presence of nanoparticles is investigated. The Lie symmetry group transformations are used to convert the boundary layer equations into non-linear ordinary differential equations. The dimensionless governing equations are solved numerically using Bvp4c with MATLAB, which is a collocation method equivalent to the fourth order mono-implicit Runge-Kutta method. The effects of some physical parameters, such as the elastic parameter K, the Hartmann number M, the Prandtl number Pr, the Brownian motion Nb, the thermophoresis parameter Nt and the Lewis number Le, on the velocity, temperature and nanoparticle fraction are studied numerically especially when suction and injection at the sheet are considered.

  4. Investigations on the processing of solid silicon rubber in blow moulding

    NASA Astrophysics Data System (ADS)

    Hopmann, Ch.; Funk, A.; Windeck, C.

    2015-05-01

    Complex hollow parts made of thermoplastics are often produced in the extrusion blow moulding process. This cost-efficient production technique with a high reproducibility, a high degree of automation and short cycle times has not been adapted for rubber processing until now. Current research activities at IKV focus on the processing of silicone rubber in extrusion blow moulding with an adapted processing and rapid cross-linking systems. The blow moulding process allows an automated and effective production of complex hollow parts made of solid silicone rubber in one step. The use of expensive core techniques, which lead to comparatively high reject rates in injection moulding, is not necessary. Expensive and time-consuming assembly steps can be reduced. This substantially increases the efficiency of the process. A systematic material selection of different solid silicone rubber compounds and cross-linking systems for the extrusion blow moulding process is a major focus of investigation. In this context, the term blow mouldability of polymers is defined and the suitability of solid silicone rubbers in combination with cross-linking systems for the blow moulding process is analysed. Characteristic mechanical and physical properties allow the identification of suitable material systems and give advice for the implementation of the new process. Extrusion blow moulding of solid silicone rubber is a new and innovative manufacturing concept to produce elastomeric hollow parts. Influences on the forming process are not known for silicone rubber yet. Therefore, to obtain a detailed process description is another focus of the research project. This includes the forming process, the processing and the influences of the material and the curing reaction on the processing. In the first instance, the investigation and description of the forming process as well as the detailed analysis of the processing parameters, such as curing time, mould temperature, wall thickness of the

  5. Blowing in the Wind Animations

    NASA Technical Reports Server (NTRS)

    2008-01-01

    These are two separate, side-by-side animations made from the same nine images the Surface Stereo Imager (SSI) on NASA's Phoenix Mars Lander took looking into the sky after 5:17 p.m. local time on Sol 8 (June 2, 2008), the eighth Martian day of the mission. The SSI was pointed almost straight up, toward the southwest. Zenith is near the top of the center frame.

    In the left animation, the images were stretched to enhance contrast. The right animation highlights variations between each image and the next. The variations are likely dust blown by winds passing through the SSI's field of view. The images suggest the dust is blowing from west to east.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  6. Blowing up the Earth

    NASA Astrophysics Data System (ADS)

    Benge, Raymond

    2006-10-01

    An occasional theme in science fiction involves blowing up a planet. In ``Star Wars,'' the Death Star blows up Alderan. In ``The Hitchhiker's Guide to the Galaxy,'' a Vorgon destructor fleet blows up Earth to make room for a cosmic bypass. So, as an exercise for upper division students, or the more advance first year calculus based physics students, the energy needed to disassemble Earth can be computed. Assuming that advanced scifi aliens get their energy from matter-antimatter interactions, students can then compute the amount of antimatter needed to accomplish the task.

  7. Failure to attain stretched penile length after intracavernosal injection of a vasodilator agent is predictive of veno-occlusive dysfunction on penile duplex Doppler ultrasonography.

    PubMed

    Yafi, F A; Libby, R P; McCaslin, I R; Sangkum, P; Sikka, S C; Hellstrom, W J G

    2015-09-01

    Penile duplex Doppler ultrasound (PDDU) assesses the etiology of erectile dysfunction. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) are common PDDU parameters. We assessed whether stretched penile length (SPL) in the flaccid state and measured penile length at peak erection after intracavernosal injection (ICI) of a vasodilator during PDDU correlated with the etiology of erectile dysfunction. We performed a retrospective review of 93 patients who underwent PDDU for erectile dysfunction. Normal and stretched penile length were measured, both at a flaccid state prior to ICI and at peak erection during PDDU. Collected data included patient demographics, vascular, and anatomic parameters. The mean age was 52 years. SPL was equivalent to peak penile length after ICI in 60 patients (65%, group 1) and did not match in 33 (35%, group 2). There were no significant differences between the two groups in terms of flaccid, stretched, and post-ICI erect penile lengths, IIEF score, PSV, percent rigidity or tumescence, and vasodilator dose used. Patients in group 2 had less of a change in penile length from flaccid to erect state (36% vs. 44%, p = 0.02), higher EDV (12.0 vs. 8.5, p = 0.041), lower RI (0.6 vs. 1.0, p = 0.046), and more veno-occlusive dysfunction (82% vs. 53%, p = 0.001). On multivariate analysis, failure to reach maximum SPL at peak ICI erection (OR 2.255, CI 1.191-4.271, p = 0.0126), EDV (OR 1.281, CI 1.115-1.471, p < 0.001) and RI (OR 0.694, CI 0.573-0.723, p = 0.009) predicted veno-occlusive dysfunction. Failure to reach maximal SPL during PDDU using ICI with a vasodilator agent predicted veno-occlusive dysfunction, which is independent of both penile rigidity and tumescence. This measurement could serve as another diagnostic tool for predicting veno-occlusive dysfunction when PDDU is not readily available. Limitations include the subjective nature of penile measurements and different PGE1 doses used. PMID

  8. "The 400 Blows."

    ERIC Educational Resources Information Center

    McLaughlin, Frank

    1967-01-01

    Francois Truffaut's film classic, "The 400 Blows," can provide artistic material for English teachers who wish to design a unit on the individual and society, on alienation, or on growing up. In the film, a powerful image of the terrifying isolation that the adolescent, Doinel, experiences is presented through repeated camera shots of symbolic…

  9. Blow out preventer

    SciTech Connect

    Bruce, A.I.

    1980-06-10

    In oil and gas well pumping apparatus, a polish rod reciprocates through a stuffing box and connects to a submersible pump through a tubing string or the like. When servicing, it is desirable to close off the gas or oil pressure from below and hydraulic fluid is routed from a remote location to the blow out preventer. The blow out preventer consists of a cylindrical casing with a cap screw threadably engaged to the upper end thereof and containing a cylindrical spool or the like formed from elastomeric material having an annular channel around the outer perimeter which is operatively connected to the source of hydraulic fluid. When it is desired to close off the blow out preventer, hydraulic fluid is pumped under pressure to the channel thus forcing the center of the spool inwardly and clamping same around the polish rod thereby closing off the passageway around the polish rod. O rings surround the spool above and below the channel and assist in sealing. Upper and lower steps in the casing slope outwardly and away from one another to facilitate the return of the spool to the normal position when pressure is released.

  10. Stretched Inertial Jets

    NASA Astrophysics Data System (ADS)

    Ghabache, Elisabeth; Antkowiak, Arnaud; Seon, Thomas; Villermaux, Emmanuel

    2015-11-01

    Liquid jets often arise as short-lived bursting liquid flows. Cavitation or impact-driven jets, bursting champagne bubbles, shaped-charge jets, ballistospores or drop-on-demand inkjet printing are a few examples where liquid jets are suddenly released. The trademark of all these discharge jets is the property of being stretched, due to the quenching injection. the present theoretical and experimental investigation, the structure of the jet flow field will be unraveled experimentally for a few emblematic occurrences of discharge jets. Though the injection markedly depends on each flow configuration, the jet velocity field will be shown to be systematically and rapidly attracted to the universal stretching flow z/t. The emergence of this inertial attractor actually only relies on simple kinematic ingredients, and as such is fairly generic. The universality of the jet velocity structure will be discussed.

  11. Stretch Marks

    MedlinePlus

    ... changes that can go with bodybuilding. People who use steroid-containing skin creams or ointments (such as hydrocortisone) for more than a few weeks may also get stretch marks. So might people who have to ... surgeon. These doctors may use one of many types of treatments — from actual ...

  12. Diurnal patterns of blowing sand

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diurnal pattern of blowing sand results from a complex process that involves an interaction between solar heating, thermal instability, atmospheric turbulence, wind strength, and surface threshold conditions. During the day, solar heating produces thermal instability, which enhances the convect...

  13. MHD flow and heat transfer of a viscous fluid over a radially stretching power-law sheet with suction/injection in a porous medium

    NASA Astrophysics Data System (ADS)

    Khan, M.; Munir, A.; Shahzad, A.; Shah, A.

    2015-03-01

    A steady boundary layer flow and heat transfer over a radially stretching isothermal porous sheet is analyzed. Stretching is assumed to follow a radial power law, and the fluid is electrically conducting in the presence of a transverse magnetic field with a very small magnetic Reynolds number. The governing nonlinear partial differential equations are reduced to a system of nonlinear ordinary differential equations by using appropriate similarity transformations, which are solved analytically by the homotopy analysis method (HAM) and numerically by employing the shooting method with the adaptive Runge-Kutta method and Broyden's method in the domain [0,∞). Analytical expressions for the velocity and temperature fields are derived. The influence of pertinent parameters on the velocity and temperature profiles is discussed in detail. The skin friction coefficient and the local Nusselt number are calculated as functions of several influential parameters. The results predicted by both methods are demonstrated to be in excellent agreement. Moreover, HAM results for a particular problem are also compared with exact solutions.

  14. Blowing Flap Experiment: PIV Measurements

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Stead, Daniel J.; Bremmer, David M.

    2004-01-01

    PIV measurements of the flow in the region of a flap side edge are presented for several flap configurations. The test model is a NACA 63(sub 2)-215 Hicks Mod-B main element airfoil with a half-span Fowler flap. Air is blown from small slots located along the flap side edge on either the top, bottom or side surfaces. The test set up is described and flow measurements for a baseline and three blowing flap configurations are presented. The effects that the flap tip jets have on the structure of the flap side edge flow are discussed for each of the flap configurations tested. The results indicate that blowing air from a slot located along the top surface of the flap greatly weakened the top vortex system and pushed it further off the top surface. Blowing from the bottom flap surface kept the strong side vortex further outboard while blowing from the side surface only strengthened the flap vortex system. It is concluded that blowing from the top or bottom surfaces of the flap may lead to a reduction of flap side edge noise.

  15. Stretching Impacts Inflammation Resolution in Connective Tissue.

    PubMed

    Berrueta, Lisbeth; Muskaj, Igla; Olenich, Sara; Butler, Taylor; Badger, Gary J; Colas, Romain A; Spite, Matthew; Serhan, Charles N; Langevin, Helene M

    2016-07-01

    Acute inflammation is accompanied from its outset by the release of specialized pro-resolving mediators (SPMs), including resolvins, that orchestrate the resolution of local inflammation. We showed earlier that, in rats with subcutaneous inflammation of the back induced by carrageenan, stretching for 10 min twice daily reduced inflammation and improved pain, 2 weeks after carrageenan injection. In this study, we hypothesized that stretching of connective tissue activates local pro-resolving mechanisms within the tissue in the acute phase of inflammation. In rats injected with carrageenan and randomized to stretch versus no stretch for 48 h, stretching reduced inflammatory lesion thickness and neutrophil count, and increased resolvin (RvD1) concentrations within lesions. Furthermore, subcutaneous resolvin injection mimicked the effect of stretching. In ex vivo experiments, stretching of connective tissue reduced the migration of neutrophils and increased tissue RvD1 concentration. These results demonstrate a direct mechanical impact of stretching on inflammation-regulation mechanisms within connective tissue. PMID:26588184

  16. Get up and Stretch

    ERIC Educational Resources Information Center

    Crupi, Jeffrey

    2004-01-01

    Daily stretching has many benefits for one's body. It can relieve stress and tension, it increases flexibility and it can help prevent injuries. There are many stretching exercises that a teacher can do with his or her students to help promote daily stretching routines. In this article, the author presents several stretching exercises and some…

  17. Diurnal patterns of blowing sand

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diurnal pattern of blowing sand results from a complex process that involves the interaction between the sun, wind, and earth. During the day, solar heating produces thermal instability, which enhances the convective mixing of high momentum winds from the upper levels of the atmosphere to the s...

  18. 21 CFR 868.5220 - Blow bottle.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Blow bottle. 868.5220 Section 868.5220 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5220 Blow bottle. (a) Identification. A blow bottle is a device... into the device to move a column of water from one bottle to another. (b) Classification. Class...

  19. 21 CFR 868.5220 - Blow bottle.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blow bottle. 868.5220 Section 868.5220 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5220 Blow bottle. (a) Identification. A blow bottle is a device... into the device to move a column of water from one bottle to another. (b) Classification. Class...

  20. Control of Cavity Resonance Using Oscillatory Blowing

    NASA Technical Reports Server (NTRS)

    Scarfe, Alison Lamp; Chokani, Ndaona

    2000-01-01

    The near-zero net mass oscillatory blowing control of a subsonic cavity flow has been experimentally investigated. An actuator was designed and fabricated to provide both steady and oscillatory blowing over a range of blowing amplitudes and forcing frequencies. The blowing was applied just upstream of the cavity front Wall through interchangeable plate configurations These configurations enabled the effects of hole size, hole shape, and blowing angle to be examined. A significant finding is that in terms of the blowing amplitude, the near zero net mass oscillatory blowing is much more effective than steady blowing; momentum coefficients Lip two orders of magnitude smaller than those required for steady blowing are sufficient to accomplish the same control of cavity resonance. The detailed measurements obtained in the experiment include fluctuating pressure data within the cavity wall, and hot-wire measurements of the cavity shear layer. Spectral and wavelet analysis techniques are applied to understand the dynamics and mechanisms of the cavity flow with control. The oscillatory blowing, is effective in enhancing the mixing in the cavity shear layer and thus modifying the feedback loop associated with the cavity resonance. The nonlinear interactions in the cavity flow are no longer driven by the resonant cavity modes but by the forcing associated with the oscillatory blowing. The oscillatory blowing does not suppress the mode switching behavior of the cavity flow, but the amplitude modulation is reduced.

  1. 21 CFR 868.5220 - Blow bottle.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Blow bottle. 868.5220 Section 868.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5220 Blow bottle. (a) Identification. A blow bottle is a...

  2. 21 CFR 868.5220 - Blow bottle.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Blow bottle. 868.5220 Section 868.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5220 Blow bottle. (a) Identification. A blow bottle is a...

  3. 21 CFR 868.5220 - Blow bottle.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Blow bottle. 868.5220 Section 868.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5220 Blow bottle. (a) Identification. A blow bottle is a...

  4. Black Hole Blows Big Bubble

    NASA Astrophysics Data System (ADS)

    2010-07-01

    Combining observations made with ESO's Very Large Telescope and NASA's Chandra X-ray telescope, astronomers have uncovered the most powerful pair of jets ever seen from a stellar black hole. This object, also known as a microquasar, blows a huge bubble of hot gas, 1000 light-years across, twice as large and tens of times more powerful than other known microquasars. The discovery is reported this week in the journal Nature. "We have been astonished by how much energy is injected into the gas by the black hole," says lead author Manfred Pakull. "This black hole is just a few solar masses, but is a real miniature version of the most powerful quasars and radio galaxies, which contain black holes with masses of a few million times that of the Sun." Black holes are known to release a prodigious amount of energy when they swallow matter. It was thought that most of the energy came out in the form of radiation, predominantly X-rays. However, the new findings show that some black holes can release at least as much energy, and perhaps much more, in the form of collimated jets of fast moving particles. The fast jets slam into the surrounding interstellar gas, heating it and triggering an expansion. The inflating bubble contains a mixture of hot gas and ultra-fast particles at different temperatures. Observations in several energy bands (optical, radio, X-rays) help astronomers calculate the total rate at which the black hole is heating its surroundings. The astronomers could observe the spots where the jets smash into the interstellar gas located around the black hole, and reveal that the bubble of hot gas is inflating at a speed of almost one million kilometres per hour. "The length of the jets in NGC 7793 is amazing, compared to the size of the black hole from which they are launched," says co-author Robert Soria [1]. "If the black hole were shrunk to the size of a soccer ball, each jet would extend from the Earth to beyond the orbit of Pluto." This research will help

  5. Black Hole Blows Big Bubble

    NASA Astrophysics Data System (ADS)

    2010-07-01

    Combining observations made with ESO's Very Large Telescope and NASA's Chandra X-ray telescope, astronomers have uncovered the most powerful pair of jets ever seen from a stellar black hole. This object, also known as a microquasar, blows a huge bubble of hot gas, 1000 light-years across, twice as large and tens of times more powerful than other known microquasars. The discovery is reported this week in the journal Nature. "We have been astonished by how much energy is injected into the gas by the black hole," says lead author Manfred Pakull. "This black hole is just a few solar masses, but is a real miniature version of the most powerful quasars and radio galaxies, which contain black holes with masses of a few million times that of the Sun." Black holes are known to release a prodigious amount of energy when they swallow matter. It was thought that most of the energy came out in the form of radiation, predominantly X-rays. However, the new findings show that some black holes can release at least as much energy, and perhaps much more, in the form of collimated jets of fast moving particles. The fast jets slam into the surrounding interstellar gas, heating it and triggering an expansion. The inflating bubble contains a mixture of hot gas and ultra-fast particles at different temperatures. Observations in several energy bands (optical, radio, X-rays) help astronomers calculate the total rate at which the black hole is heating its surroundings. The astronomers could observe the spots where the jets smash into the interstellar gas located around the black hole, and reveal that the bubble of hot gas is inflating at a speed of almost one million kilometres per hour. "The length of the jets in NGC 7793 is amazing, compared to the size of the black hole from which they are launched," says co-author Robert Soria [1]. "If the black hole were shrunk to the size of a soccer ball, each jet would extend from the Earth to beyond the orbit of Pluto." This research will help

  6. Black Hole Blows Big Bubble

    NASA Astrophysics Data System (ADS)

    2010-07-01

    Combining observations made with ESO's Very Large Telescope and NASA's Chandra X-ray telescope, astronomers have uncovered the most powerful pair of jets ever seen from a stellar black hole. This object, also known as a microquasar, blows a huge bubble of hot gas, 1000 light-years across, twice as large and tens of times more powerful than other known microquasars. The discovery is reported this week in the journal Nature. "We have been astonished by how much energy is injected into the gas by the black hole," says lead author Manfred Pakull. "This black hole is just a few solar masses, but is a real miniature version of the most powerful quasars and radio galaxies, which contain black holes with masses of a few million times that of the Sun." Black holes are known to release a prodigious amount of energy when they swallow matter. It was thought that most of the energy came out in the form of radiation, predominantly X-rays. However, the new findings show that some black holes can release at least as much energy, and perhaps much more, in the form of collimated jets of fast moving particles. The fast jets slam into the surrounding interstellar gas, heating it and triggering an expansion. The inflating bubble contains a mixture of hot gas and ultra-fast particles at different temperatures. Observations in several energy bands (optical, radio, X-rays) help astronomers calculate the total rate at which the black hole is heating its surroundings. The astronomers could observe the spots where the jets smash into the interstellar gas located around the black hole, and reveal that the bubble of hot gas is inflating at a speed of almost one million kilometres per hour. "The length of the jets in NGC 7793 is amazing, compared to the size of the black hole from which they are launched," says co-author Robert Soria [1]. "If the black hole were shrunk to the size of a soccer ball, each jet would extend from the Earth to beyond the orbit of Pluto." This research will help

  7. Black Hole Blows Big Bubble

    NASA Astrophysics Data System (ADS)

    2010-07-01

    Combining observations made with ESO's Very Large Telescope and NASA's Chandra X-ray telescope, astronomers have uncovered the most powerful pair of jets ever seen from a stellar black hole. This object, also known as a microquasar, blows a huge bubble of hot gas, 1000 light-years across, twice as large and tens of times more powerful than other known microquasars. The discovery is reported this week in the journal Nature. "We have been astonished by how much energy is injected into the gas by the black hole," says lead author Manfred Pakull. "This black hole is just a few solar masses, but is a real miniature version of the most powerful quasars and radio galaxies, which contain black holes with masses of a few million times that of the Sun." Black holes are known to release a prodigious amount of energy when they swallow matter. It was thought that most of the energy came out in the form of radiation, predominantly X-rays. However, the new findings show that some black holes can release at least as much energy, and perhaps much more, in the form of collimated jets of fast moving particles. The fast jets slam into the surrounding interstellar gas, heating it and triggering an expansion. The inflating bubble contains a mixture of hot gas and ultra-fast particles at different temperatures. Observations in several energy bands (optical, radio, X-rays) help astronomers calculate the total rate at which the black hole is heating its surroundings. The astronomers could observe the spots where the jets smash into the interstellar gas located around the black hole, and reveal that the bubble of hot gas is inflating at a speed of almost one million kilometres per hour. "The length of the jets in NGC 7793 is amazing, compared to the size of the black hole from which they are launched," says co-author Robert Soria [1]. "If the black hole were shrunk to the size of a soccer ball, each jet would extend from the Earth to beyond the orbit of Pluto." This research will help

  8. Blow molding of melt processible rubber

    SciTech Connect

    Abell, W.R.; Stuart, R.E.; Myrick, R.E.

    1991-07-01

    This article discusses the advantages of making hollow rubber parts by blow molding thermoplastic elastomers (TPEs) versus conventional rubber processing. It describes the various types of blow molding processes and it provides some insight into the rheological properties of melt processible rubber (MPR) and how MPR should be molded by each of these processes. A number of blow molded applications for MPR are also discussed.

  9. Blowing Circulation Control on a Seaplane Airfoil

    NASA Astrophysics Data System (ADS)

    Guo, B. D.; Liu, P. Q.; Qu, Q. L.

    2011-09-01

    RANS simulations are presented for blowing circulation control on a seaplane airfoil. Realizable k-epsilon turbulent model and pressure-based coupled algorithm with second-order discretization were adopted to simulate the compressible flow. Both clear and simple flap configuration were simulated with blowing momentum coefficient Cμ = 0, 0.15 and 0.30. The results show that blowing near the airfoil trailing edge could enhance the Coanda effect, delay the flow separation, and increase the lift coefficient dramatically. The blowing circulation control is promising to apply to taking off and landing of an amphibious aircraft or seaplane.

  10. Stretched Wire Mechanics

    SciTech Connect

    Bowden, Gordon; /SLAC

    2005-09-06

    Stretched wires are beginning to play an important role in the alignment of accelerators and synchrotron light sources. Stretched wires are proposed for the alignment of the 130 meter long LCLS undulator. Wire position technology has reached sub-micron resolution yet analyses of perturbations to wire straightness are hard to find. This paper considers possible deviations of stretched wire from the simple 2-dimensional catenary form.

  11. Blow collection as a non-invasive method for measuring cortisol in the beluga (Delphinapterus leucas).

    PubMed

    Thompson, Laura A; Spoon, Tracey R; Goertz, Caroline E C; Hobbs, Roderick C; Romano, Tracy A

    2014-01-01

    Non-invasive sampling techniques are increasingly being used to monitor glucocorticoids, such as cortisol, as indicators of stressor load and fitness in zoo and wildlife conservation, research and medicine. For cetaceans, exhaled breath condensate (blow) provides a unique sampling matrix for such purposes. The purpose of this work was to develop an appropriate collection methodology and validate the use of a commercially available EIA for measuring cortisol in blow samples collected from belugas (Delphinapterus leucas). Nitex membrane stretched over a petri dish provided the optimal method for collecting blow. A commercially available cortisol EIA for measuring human cortisol (detection limit 35 pg ml-1) was adapted and validated for beluga cortisol using tests of parallelism, accuracy and recovery. Blow samples were collected from aquarium belugas during monthly health checks and during out of water examination, as well as from wild belugas. Two aquarium belugas showed increased blow cortisol between baseline samples and 30 minutes out of water (Baseline, 0.21 and 0.04 µg dl-1; 30 minutes, 0.95 and 0.14 µg dl-1). Six wild belugas also showed increases in blow cortisol between pre and post 1.5 hour examination (Pre 0.03, 0.23, 0.13, 0.19, 0.13, 0.04 µg dl-1, Post 0.60, 0.31, 0.36, 0.24, 0.14, 0.16 µg dl-1). Though this methodology needs further investigation, this study suggests that blow sampling is a good candidate for non-invasive monitoring of cortisol in belugas. It can be collected from both wild and aquarium animals efficiently for the purposes of health monitoring and research, and may ultimately be useful in obtaining data on wild populations, including endangered species, which are difficult to handle directly. PMID:25464121

  12. Stretching: Does It Help?

    ERIC Educational Resources Information Center

    Vardiman, Phillip; Carrand, David; Gallagher, Philip M.

    2010-01-01

    Stretching prior to activity is universally accepted as an important way to improve performance and help prevent injury. Likewise, limited flexibility has been shown to decrease functional ability and predispose a person to injuries. Although this is commonly accepted, appropriate stretching for children and adolescents involved with sports and…

  13. Stretch Band Exercise Program

    ERIC Educational Resources Information Center

    Skirka, Nicholas; Hume, Donald

    2007-01-01

    This article discusses how to use stretch bands for improving total body fitness and quality of life. A stretch band exercise program offers a versatile and inexpensive option to motivate participants to exercise. The authors suggest practical exercises that can be used in physical education to improve or maintain muscular strength and endurance,…

  14. Control of Flow Structure on Low Swept Delta Wing with Steady Leading Edge Blowing

    NASA Astrophysics Data System (ADS)

    Ozturk, Ilhan; Zharfa, Mohammadreza; Yavuz, Mehmet Metin

    2014-11-01

    Interest in unmanned combat air vehicles (UCAVs) and micro air vehicles (MAVs) has stimulated investigation of the flow structure, as well as its control, on delta wings having low and moderate values of sweep angle. In the present study, the flow structure is characterized on a delta wing of low sweep 35-degree angle, which is subjected to steady leading edge blowing. The techniques of laser illuminated smoke visualization, laser Doppler anemometry (LDA), and surface pressure measurements are employed to investigate the steady and unsteady nature of the flow structure on delta wing, in relation to the dimensionless magnitude of the blowing coefficient. Using statistics and spectral analysis, unsteadiness of the flow structure is studied in detail. Different injection locations are utilized to apply different blowing patterns in order to identify the most efficient control, which provides the upmost change in the flow structure with the minimum energy input. The study aims to find the optimum flow control strategy to delay or to prevent the stall and possibly to reduce the buffeting on the wing surface. Since the blowing set-up is computer controlled, the unsteady blowing patterns compared to the present steady blowing patterns will be studied next. This project was supported by the Scientific and Technological Research Council of Turkey (Project Number: 3501 111M732).

  15. FEASTING BLACK HOLE BLOWS BUBBLES

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A monstrous black hole's rude table manners include blowing huge bubbles of hot gas into space. At least, that's the gustatory practice followed by the supermassive black hole residing in the hub of the nearby galaxy NGC 4438. Known as a peculiar galaxy because of its unusual shape, NGC 4438 is in the Virgo Cluster, 50 million light-years from Earth. These NASA Hubble Space Telescope images of the galaxy's central region clearly show one of the bubbles rising from a dark band of dust. The other bubble, emanating from below the dust band, is barely visible, appearing as dim red blobs in the close-up picture of the galaxy's hub (the colorful picture at right). The background image represents a wider view of the galaxy, with the central region defined by the white box. These extremely hot bubbles are caused by the black hole's voracious eating habits. The eating machine is engorging itself with a banquet of material swirling around it in an accretion disk (the white region below the bright bubble). Some of this material is spewed from the disk in opposite directions. Acting like high-powered garden hoses, these twin jets of matter sweep out material in their paths. The jets eventually slam into a wall of dense, slow-moving gas, which is traveling at less than 223,000 mph (360,000 kph). The collision produces the glowing material. The bubbles will continue to expand and will eventually dissipate. Compared with the life of the galaxy, this bubble-blowing phase is a short-lived event. The bubble is much brighter on one side of the galaxy's center because the jet smashed into a denser amount of gas. The brighter bubble is 800 light-years tall and 800 light-years across. The observations are being presented June 5 at the American Astronomical Society meeting in Rochester, N.Y. Both pictures were taken March 24, 1999 with the Wide Field and Planetary Camera 2. False colors were used to enhance the details of the bubbles. The red regions in the picture denote the hot gas

  16. PIV Measurements on a Blowing Flap

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Stead, Daniel J.

    2004-01-01

    PIV measurements of the flow in the region of a flap side edge are presented for several blowing flap configurations. The test model is a NACA 63(sub 2)-215 Hicks Mod-B main-element airfoil with a half-span Fowler flap. Air is blown from small slots located along the flap side edge on either the top, bottom or side surfaces. The test set up is described and flow measurements for a baseline and three blowing flap configurations are presented. The effects that the flap tip jets have on the structure of the flap side edge flow are discussed for each of the flap configurations tested. The results indicate that blowing air from a slot located along the top surface of the flap greatly weakened the top vortex system and pushed it further off the top surface. Blowing from the bottom flap surface kept the strong side vortex further outboard while blowing from the side surface only strengthened the vortex system or accelerated the merging of the side vortex to the flap top surface. It is concluded that blowing from the top or bottom surfaces of the flap may lead to a reduction of flap side edge noise.

  17. Blowing Snow Over the Antarctic Plateau

    NASA Technical Reports Server (NTRS)

    Mahesh, Ashwin; Eager, Rebecca; Campbell, James R.; Spinhirne, James D.

    2002-01-01

    Studies of blowing snow over Antarctica have been limited greatly by the remoteness and harsh conditions of the region. Space-based observations are also of lesser value than elsewhere, given the similarities between ice clouds and snow-covered surfaces, both at infrared and visible wavelengths. It is only in recent years that routine ground-based observation programs have acquired sufficient data to overcome the gap in our understanding of surface blowing snow. In this paper, observations of blowing snow from visual observers' records as well as ground-based spectral and lidar programs at South Pole station are analyzed to obtain the first climatology of blowing snow over the Antarctic plateau. Occurrence frequencies, correlation with wind direction and speed, typical layer heights, as well as optical depths are determined. Blowing snow is seen in roughly one third of the visual observations and occurs under a narrow range of wind directions. The near-surface layers typically a few hundred meters thick emit radiances similar to those from thin clouds. Because blowing snow remains close to the surface and is frequently present, it will produce small biases in space-borne altimetry; these must be properly estimated and corrected.

  18. Augmentation of maneuver performance by spanwise blowing

    NASA Technical Reports Server (NTRS)

    Erickson, G. E.; Campbell, J. F.

    1977-01-01

    A generalized wind tunnel model was tested to investigate new component concepts utilizing spanwise blowing to provide improved maneuver characteristics for advanced fighter aircraft. Primary emphasis was placed on high angle of attack performance, stability, and control at subsonic speeds. Spanwise blowing on a 44 deg swept trapezoidal wing resulted in leading edge vortex enhancement with subsequent large vortex-induced lift increments and drag polar improvements at the higher angles of attack. Small deflections of a leading edge flap delayed these lift and drag benefits to higher angles of attack. In addition, blowing was more effective at higher Mach numbers. Spanwise blowing in conjunction with a deflected trailing edge flap resulted in lift and drag benefits that exceeded the summation of the effects of each high lift device acting alone. Asymmetric blowing was an effective lateral control device at the higher angles of attack. Spanwise blowing on the wing reduced horizontal tail loading and improved the lateral-directional stability characteristics of a wing-horizontal tail-vertical tail configuration.

  19. Morphology and Mechanical Properties of Poly(Ethylene Terephthalate) Stretched Above the Glass Transition Temperature

    NASA Astrophysics Data System (ADS)

    Todorov, Lyudmil V.; Viana, Júlio C.

    2007-04-01

    This study presents an experimental investigation into the development of the strain-induced morphology of amorphous poly(ethylene terephthalate), PET, stretched above its glass transition temperature. The present work aims at: i) defining the most important processing parameters that govern the structure formation and its significance; ii) characterising the mechanical properties of uniaxial stretched glassy PET, as an approach for industrial stretch-blow moulding techniques; iii) establishing structure-properties relationships. Compression moulded amorphous PET was uniaxial stretched with variations of following stretching parameters: stretching temperature, Tst, stretching velocity, Vst, and stretching ratio, λst, that were varied in two levels according to a L8 Taguchi orthogonal array. The developed morphologies were observed by differential scanning calorimetry (DSC), birefringence and Wide-Angle X-ray Scattering (WAXS). The mechanical behaviour was assessed in tensile testing at 15 mm.min-1 and room temperature. The results were treated by a statistical ANOVA tool. A strong thermal and mechanical coupling is evidenced in the stretching process, significantly influencing the morphology development. The main stretching parameters controlling microstructure formation were defined. The relationships between the microstructure and mechanical properties were established too.

  20. Computational analysis of forebody tangential slot blowing

    NASA Technical Reports Server (NTRS)

    Gee, Ken; Agosta-Greenman, Roxana M.; Rizk, Yehia M.; Schiff, Lewis B.; Cummings, Russell M.

    1994-01-01

    An overview of the computational effort to analyze forebody tangential slot blowing is presented. Tangential slot blowing generates side force and yawing moment which may be used to control an aircraft flying at high-angle-of-attack. Two different geometries are used in the analysis: (1) The High Alpha Research Vehicle; and (2) a generic chined forebody. Computations using the isolated F/A-18 forebody are obtained at full-scale wind tunnel test conditions for direct comparison with available experimental data. The effects of over- and under-blowing on force and moment production are analyzed. Time-accurate solutions using the isolated forebody are obtained to study the force onset timelag of tangential slot blowing. Computations using the generic chined forebody are obtained at experimental wind tunnel conditions, and the results compared with available experimental data. This computational analysis compliments the experimental results and provides a detailed understanding of the effects of tangential slot blowing on the flow field about simple and complex geometries.

  1. Low-Speed Fan Noise Reduction With Trailing Edge Blowing

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; Tweedt, Daniel L.; Fite, E. Brian; Envia, Edmane

    2002-01-01

    An experimental proof-of-concept test was conducted to demonstrate reduction of rotor-stator interaction noise through rotor-trailing edge blowing. The velocity deficit from the viscous wake of the rotor blades was reduced by injecting air into the wake from a trailing edge slot. Composite hollow rotor blades with internal flow passages were designed based on analytical codes modeling the internal flow. The hollow blade with interior guide vanes creates flow channels through which externally supplied air flows from the root of the blade to the trailing edge. The impact of the rotor wake-stator interaction on the acoustics was also predicted analytically. The Active Noise Control Fan, located at the NASA Glenn Research Center, was used as the proof- of-concept test bed. In-duct mode and farfield directivity acoustic data were acquired at blowing rates (defined as mass supplied to trailing edge blowing system divided by fan mass flow) ranging from 0.5 to 2.0 percent. The first three blade passing frequency harmonics at fan rotational speeds of 1700 to 1900 rpm were analyzed. The acoustic tone power levels (PWL) in the inlet and exhaust were reduced 11.5 and -0.1, 7.2 and 11.4, 11.8 and 19.4 PWL dB, respectively. The farfield tone power levels at the first three harmonics were reduced 5.4, 10.6, and 12.4 dB PWL. At selected conditions, two-component hotwire and stator vane unsteady surface pressures were acquired. These measurements illustrate the physics behind the noise reduction.

  2. Groin stretch (image)

    MedlinePlus

    Stand with your legs wide apart. Shift your weight to one side, bending your knee somewhat. Do not let your knee bend beyond your ankle; in other words, you should be able to look down and still see your toes. You should feel the stretch in your opposite ...

  3. Stretching to Understand Proteins

    NASA Astrophysics Data System (ADS)

    Cieplak, Marek

    2007-03-01

    Mechanical stretching of single proteins has been studied experimentally for about 50 proteins yielding a variety of force patterns and values of the peak forces. We have performed a theoretical survey of 7749 proteins of known native structure and map out the landscape of possible dynamical behaviors unders stretching at constant speed. The model used is constructed based on the native geometry. It is solved by methods of molecular dynamics and validated by comparing the theoretical predictions to experimental results. We characterize the distribution of peak forces and on correlations with the system size and with the structure classification as characterized by the CATH scheme. We identify proteins with the biggest forces and show that they belong to few topology classes. We determine which protein segments act as mechanical clamps and show that, in most cases, they correspond to long stretches of parallel beta-strands, but other mechanisms are also possible. We then consider stretching by fluid flows. We show that unfolding induced by a uniform flow shows a richer behavior than that in the force clamp. The dynamics of unfolding is found to depend strongly on the selection of the amino acid, usually one of the termini, which is anchored. These features offer potentially wider diagnostic tools to investigate structure of proteins compared to experiments based on the atomic force microscopy.

  4. Stretch That Budget!

    ERIC Educational Resources Information Center

    Walker, John R.

    1976-01-01

    Discusses ways in which industrial education teachers can stretch their budgets, which include reducing waste to a minimum, keeping an accurate and up-to-date inventory, trading surplus or excess materials with neighboring schools, and planning programs more carefully. Money-saving tips concerned with metals, plastics, woods, and printing are also…

  5. Development of polyimide foams with blowing agents

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Sorathia, Usman A. K. (Inventor); Lee, Raymond (Inventor)

    1985-01-01

    A method of preparing a polyimide foam which includes the steps of: preparing, foaming, and curing a precursor containing at least one alkyl ester of 3,3'4,4'-benzophenonetetracarboxylic acid; a meta- or para-substituted aromatic diamine; a heterocyclic diamine; an aliphatic diamine; and a solid blowing agent. The blowing agent is added to said precursor in a concentration which is sufficient to effect at least one of the following attributes of the foam: cell size, proportion of open cells, cell density, and indentation load deflection.

  6. 2. GENERAL VIEW OF BLOWING ENGINE HOUSE, LOOKING NORTH; BOILER ...

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

    2. GENERAL VIEW OF BLOWING ENGINE HOUSE, LOOKING NORTH; BOILER HOUSE ON LEFT; BLAST FURNACE, OVENS AND CASTING HOUSE BEYOND. - U.S. Steel Corporation, Clairton Works, Blast Furnace Blowing Engine Building, 400 State Street, Clairton, Allegheny County, PA

  7. 5. DETAIL VIEW LOOKING AT FLYWHEEL HUB OF BLOWING ENGINE. ...

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

    5. DETAIL VIEW LOOKING AT FLYWHEEL HUB OF BLOWING ENGINE. (THE MAN IS MR. FIELD CURRY). - U.S. Steel Corporation, Clairton Works, Blast Furnace Blowing Engine Building, 400 State Street, Clairton, Allegheny County, PA

  8. Stretching & Flexibility: An Interactive Encyclopedia of Stretching. [CD-ROM].

    ERIC Educational Resources Information Center

    2002

    This CD-ROM offers 140 different stretches in full-motion video sequences. It focuses on the proper techniques for overall physical fitness, injury prevention and rehabilitation, and 23 different sports (e.g., golf, running, soccer, skiing, climbing, football, and baseball). Topics include stretching for sports; stretching awareness and education…

  9. Nontraumatic orbital floor fracture after nose blowing.

    PubMed

    Sandhu, Ranjit S; Shah, Akash D

    2016-03-01

    A 40-year-old woman with no history of trauma or prior surgery presented to the emergency department with headache and left eye pain after nose blowing. Noncontrast maxillofacial computed tomography examination revealed an orbital floor fracture that ultimately required surgical repair. There are nontraumatic causes of orbital blowout fractures, and imaging should be obtained irrespective of trauma history. PMID:26973725

  10. Nontraumatic orbital floor fracture after nose blowing

    PubMed Central

    Sandhu, Ranjit S.; Shah, Akash D.

    2016-01-01

    A 40-year-old woman with no history of trauma or prior surgery presented to the emergency department with headache and left eye pain after nose blowing. Noncontrast maxillofacial computed tomography examination revealed an orbital floor fracture that ultimately required surgical repair. There are nontraumatic causes of orbital blowout fractures, and imaging should be obtained irrespective of trauma history. PMID:26973725

  11. Dinural patterns of blowing sand and dust

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diurnal pattern of blowing sand results from a complex interaction between the sun, the atmosphere, and the sand surface. During the day, solar heating produces thermal instability, which enhances convective mixing of high momentum winds from the upper levels of the atmosphere to the surface la...

  12. Drifting and blowing snow, measurements and modelling

    NASA Astrophysics Data System (ADS)

    Gordon, Mark

    2007-12-01

    Blowing snow is a frequent and significant winter weather event, and there is currently a need for more observations and measurements of blowing snow, especially in arctic and subarctic environments. A camera system has been developed to measure the size and velocity of blowing snow particles. A second camera system has been developed to measure the relative blowing snow density profile near the snow surface. These systems have been used, along with standard meteorological instruments and optical particle counters, during field campaigns at Franklin Bay, NWT, and at Churchill, MB. An electric field mill was also deployed at Franklin Bay. Results demonstrate that the particle diameters follow a Gamma distribution with 103 < d¯ < 172 mum below a height of 0.15 m and 120 < d¯ < 154 mum between 0.2 m and 1.1 m. Within the saltation layer, the mass density can be approximated by a power-law (rhos ∝ z -gamma) with an exponent of gamma ≈ 1.5 for z < 40 mm. Between 40 < z < 100 mm, in the lower suspension layer, the value of the exponent increases to a range of 1.5 < gamma < 8. At greater heights, z > 100 mm, the exponent approaches gamma ≈ l. The height of saltation shows a very weak dependence on the friction velocity, a strong dependence on temperature and relative humidity, and a weak dependence on snow age. Electric field strengths as high as 2000 V m-1 were measured at a height of 0.5 m. A model to determine electric field strength based on the distribution of blowing snow particles shows a weak agreement with measurements. Results suggest the charge is most likely generated due to either fragmentation or asymmetric rubbing, which are both strongly dependent on wind speed. Modelling studies with the Canadian Land Surface Scheme (CLASS) and previous measurements of snow depth at Goose Bay, Hay River, the Beaufort Sea, Franklin Bay, and Resolute demonstrate that blowing snow sublimation can have a substantial effect on snow depth. Adding a blowing snow

  13. Whistle-Blowing Intentions of Prospective Teachers: Education Evidence

    ERIC Educational Resources Information Center

    Gökçe, Asiye Toker

    2013-01-01

    This study investigates whistle-blowing intentions of prospective teachers. Firstly, overall ethical awareness of the participants was examined, and then their underlying ethical reasons of whistle-blowing were investigated. Besides, impact on the intention to blow whistle to internal or external parties offering their job guarantee were searched.…

  14. Stretch-Oriented Polyimide Films

    NASA Technical Reports Server (NTRS)

    Hinkley, Jeffrey A.; Klinedinst, D.; Feuz, L.

    2000-01-01

    Two thermoplastic polyimides - one amorphous, the other crystallizable -- were subjected to isothermal stretching just above their glass transition temperatures. Room-temperature strengths in the stretch direction were greatly improved and, moduli increased up to 3.6-fold. Optimum stretching conditions were determined.

  15. Comparison between two models of cooling surfaces using blowing.

    PubMed

    Mathelin, L; Bataille, F; Lallemand, A

    2001-05-01

    To protect surfaces against high temperatures, the blowing through a porous material is studied. The geometry is that of a circular cylinder in cross-flow and the effectiveness of the blowing for the thermal protection is numerically investigated. Two models are developed for the blowing simulation and comparisons are made with experimental data obtained in a heated wind-tunnel. It is shown that the blowing strongly affects the dynamical and thermal profiles over the surface, thickening the boundary layers and decreasing the external transfer coefficients. It results in a lower viscous drag and thermal stress. The wall temperature dramatically decreases with blowing and the heat flux is also affected. PMID:11460652

  16. Stretching Cells with Light

    NASA Astrophysics Data System (ADS)

    Guck, Jochen

    2003-03-01

    Trapped in a two-beam laser trap, any dielectric object experiences surface stresses induced by the laser light that lead to a "stretching" of the object. This can be explained with simple ray optics as well as with a modified Mie theory approach. Based on this phenomenon we have developed an optical tool to probe the viscoelastic properties of individual cells - an optical stretcher. The cell's deformation at a known induced stress reveals the mechanical properties of the cell and the underlying cytoskeleton. Thus, the optical stretcher can be used for contact-free microrheology on individual cells. Step-stress experiments on mouse fibroblasts reveal two main time regimes. At stress duration times shorter than a minute cells behave like a passive viscoelastic fluid. The frequency dependence of the complex shear modulus and the terminal relaxation time are consistent with a weakly entangled, transiently crosslinked actin gel, while contributions from other cytoskeletal filaments can be largely ruled out. At stretching times longer than a minute cells show an active response evidenced by a continued elongation after stretch. Malignantly transformed fibroblasts are less elastic and less viscous. Experiments on various other cell types with the optical stretcher confirm very generally that the viscoelastic response of cells changes during the progression of cancer and other diseases, which are accompanied by cytoskeletal changes, and the normal differentiation of cells. This suggests using optical deformability as a novel inherent cell marker. Instead of having to "look" for changes, light can now directly be used to "feel" for altered cells. Incorporated into a microfluidic device this can be done at rates that could eventually rival flow cytometers rendering the optical stretcher an ideal device for cytological diagnosis of disease and the screening and sorting of heterogeneous cell populations.

  17. One-Dimensional Analysis Techniques for Pulsed Blowing Distribution

    NASA Astrophysics Data System (ADS)

    Chambers, Frank

    2005-11-01

    Pulsed blowing offers reductions in bleed air requirements for aircraft flow control. Efficient pulsed blowing systems require careful design to minimize bleed air use while distributing blowing to multiple locations. Pulsed blowing systems start with a steady flow supply and process it to generate a pulsatile flow. The fluid-acoustic dynamics of the system play an important role in overall effectiveness. One-dimensional analysis techniques that in the past have been applied to ventilation systems and internal combustion engines have been adapted to pulsed blowing. Pressure wave superposition and reflection are used with the governing equations of continuity, momentum and energy to determine particle velocities and pressures through the flow field. Simulations have been performed to find changes in the amplitude and wave shape as pulses are transmitted through a simple pulsed blowing system. A general-purpose code is being developed to simulate wave transmission and allow the determination of blowing system dynamic parameters.

  18. Control of Cavity Resonance Using Steady and Oscillatory Blowing

    NASA Technical Reports Server (NTRS)

    Lamp, Alison M.; Chokani, Ndaona

    1999-01-01

    An experimental study to investigate the effect of steady and oscillatory (with zero net mass flux) blowing on cavity resonance is undertaken. The objective is to study the basic mechanisms of the control of cavity resonance. An actuator is designed and calibrated to generate either steady blowing or oscillatory blowing with A zero net mass flux. The results of the experiment show that both steady and oscillatory blowing are effective, and reduce the amplitude of the dominant resonant mode by 1OdB. The oscillatory blowing is however found to be more superior in that the same effectiveness could be accomplished with a momentum coefficient an order of magnitude smaller than for steady blowing. The experiment also confirms the results of previous computations that suggest the forcing frequency for oscillatory blowing must not be at harmonic frequencies of the cavity resonant modes.

  19. Thar She Blows! A Novel Method for DNA Collection from Cetacean Blow

    PubMed Central

    Frère, Céline H.; Krzyszczyk, Ewa; Patterson, Eric M.; Hunter, Sue; Ginsburg, Alison; Mann, Janet

    2010-01-01

    Background Molecular tools are now widely used to address crucial management and conservation questions. To date, dart biopsying has been the most commonly used method for collecting genetic data from cetaceans; however, this method has some drawbacks. Dart biopsying is considered inappropriate for young animals and has recently come under scrutiny from ethical boards, conservationists, and the general public. Thus, identifying alternative genetic collection techniques for cetaceans remains a priority, especially for internationally protected species. Methodology/Principal Findings In this study, we investigated whether blow-sampling, which involves collecting exhalations from the blowholes of cetaceans, could be developed as a new less invasive method for DNA collection. Our current methodology was developed using six bottlenose dolphins, Tursiops truncatus, housed at the National Aquarium, Baltimore (USA), from which we were able to collect both blow and blood samples. For all six individuals, we found that their mitochondrial and microsatellite DNA profile taken from blow, matched their corresponding mitochondrial and microsatellite DNA profile collected from blood. This indicates that blow-sampling is a viable alternative method for DNA collection. Conclusion/Significance In this study, we show that blow-sampling provides a viable and less invasive method for collection of genetic data, even for small cetaceans. In contrast to dart biopsying, the advantage of this method is that it capitalizes on the natural breathing behaviour of dolphins and can be applied to even very young dolphins. Both biopsy and blow-sampling require close proximity of the boat, but blow-sampling can be achieved when dolphins voluntarily bow-ride and involves no harmful contact. PMID:20811619

  20. Blow-down and blow-in of Inland`s No. 7 blast furnace

    SciTech Connect

    Ricketts, J.; Quisenberry, P.; Carter, W.

    1995-12-01

    After extensive and detailed planning, a mini-reline of the 13.7 meter No. 7 Blast Furnace was executed in November 1993. The furnace lining had 18 million metric tons of production and the bosh, belly and lower stack lining were being maintained through a scheduled grouting practice. The mini-reline was planned for 33 days and the reline work included (a) replacing the bosh, belly and lower stack alumina lining with graphite brick, (b) gunning the middle and upper stack, (c) rebuilding the furnace top, stove burners and tapholes and (d) minor repairs to other auxiliary equipment. During this 33 day reline period the two 8 meter furnaces could only produce 40% of the normal production requirement, therefore the blow-down, quench, salamander tap and blow-in activities were critical to meeting the planned schedule. The planning of these activities was started in the spring of 1993 and included review of Inland`s past blow-down and blow-in performance as well as bench marking the performance of other large blast furnaces in North America, Japan and Europe. The development of the 1993 procedures focused on opportunities to accelerate the blow-down, quench, salamander tap and blow-in as well as having a clean hearth and stack which could also save time during the demolition phase of the reline. Any time that could be saved in these activities directly translated to an early start-up and more plantwide production. This paper will cover the successful planning and implementation of these activities which resulted in a 2 day reduction in the reline schedule, an accelerated production curve and an earlier than planned use of PCI during blow-in.

  1. Blow-in fracture of the orbit.

    PubMed

    Hwang, Kun; Kim, Han Joon; Lee, Hong Sik

    2013-01-01

    We report 2 patients with blow-in fractures of the orbital floor caused by different mechanisms. In a 17-year-old boy, a sudden impact was given to the anterior maxillary wall and caused a depression fracture of a maxilla, yet the infraorbital rim remained intact. We think fragments of the orbital floor were forced into the orbit by a sudden increase in pressure in the maxillary sinus in this patient. In a 51-year-old man, the impact of a force was on the laterosuperior part of the zygoma, which pushed the zygoma medially. These 2 cases represent 2 different mechanisms of blow-in fractures of the orbital floor. PMID:24036789

  2. Stretching cells with DEAs

    NASA Astrophysics Data System (ADS)

    Akbari, S.; Rosset, S.; Shea, H. R.

    2012-04-01

    Biological cells regulate their biochemical behavior in response to mechanical stress present in their organism. Most of the available cell cultures designed to study the effect of mechanical stimuli on cells are cm2 area, far too large to monitor single cell response or have a very low throughput. We have developed two sets of high throughput single cell stretcher devices based on dielectric elastomer microactuators to stretch groups of individual cells with various strain levels in a single experiment. The first device consists of an array of 100 μm x 200 μm actuators on a non-stretched PDMS membrane bonded to a Pyrex chip, showing up to 4.7% strain at the electric field of 96 V/μm. The second device contains an array of 100 μm x 100 μm actuators on a 160% uniaxially prestretched PDMS membrane suspended over a frame. 37% strain is recorded at the nominal electric field of 114 V/μm. The performance of these devices as a cell stretcher is assessed by comparing their static and dynamic behavior.

  3. Falling liquid films with blowing and suction

    NASA Astrophysics Data System (ADS)

    Thompson, Alice B.; Tseluiko, Dmitri; Papageorgiou, Demetrios T.

    2016-01-01

    Flow of a thin viscous film down a flat inclined plane becomes unstable to long wave interfacial fluctuations when the Reynolds number based on the mean film thickness becomes larger than a critical value (this value decreases as the angle of inclination with the horizontal increases, and in particular becomes zero when the plate is vertical). Control of these interfacial instabilities is relevant to a wide range of industrial applications including coating processes and heat or mass transfer systems. This study considers the effect of blowing and suction through the substrate in order to construct from first principles physically realistic models that can be used for detailed passive and active control studies of direct relevance to possible experiments. Two different long-wave, thin-film equations are derived to describe this system; these include the imposed blowing/suction as well as inertia, surface tension, gravity and viscosity. The case of spatially periodic blowing and suction is considered in detail and the bifurcation structure of forced steady states is explored numerically to predict that steady states cease to exist for sufficiently large suction speeds since the film locally thins to zero thickness giving way to dry patches on the substrate. The linear stability of the resulting nonuniform steady states is investigated for perturbations of arbitrary wavelengths, and any instabilities are followed into the fully nonlinear regime using time-dependent computations. The case of small amplitude blowing/suction is studied analytically both for steady states and their stability. Finally, the transition between travelling waves and non-uniform steady states is explored as the suction amplitude increases.

  4. Asian elephants acquire inaccessible food by blowing.

    PubMed

    Mizuno, Kaori; Irie, Naoko; Hiraiwa-Hasegawa, Mariko; Kutsukake, Nobuyuki

    2016-01-01

    Many animals acquire otherwise inaccessible food with the aid of sticks and occasionally water. As an exception, some reports suggest that elephants manipulate breathing through their trunks to acquire inaccessible food. Here, we report on two female Asian elephants (Elephas maximus) in Kamine Zoo, Japan, who regularly blew to drive food within their reach. We experimentally investigated this behaviour by placing foods in inaccessible places. The elephants blew the food until it came within accessible range. Once the food was within range, the elephants were increasingly less likely to blow as the distance to the food became shorter. One subject manipulated her blowing duration based on food distance: longer when the food was distant. These results suggest that the elephants used their breath to achieve goals: that is, they used it not only to retrieve the food but also to fine-tune the food position for easy grasping. We also observed individual differences in the elephants' aptitude for this technique, which altered the efficiency of food acquisition. Thus, we added a new example of spontaneous behaviour for achieving a goal in animals. The use of breath to drive food is probably unique to elephants, with their dexterous trunks and familiarity with manipulating the act of blowing, which is commonly employed for self-comfort and acoustic communication. PMID:26541597

  5. An Implicit Finite Difference Solution to the Viscous Radiating Shock Layer with Strong Blowing. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Garrett, L. B.

    1971-01-01

    An implicit finite difference scheme is developed for the fully coupled solution of the viscous radiating stagnation line equations, including strong blowing. Solutions are presented for both air injection and carbon phenolic ablation products injection into air at conditions near the peak radiative heating point in an earth entry trajectory from interplanetary return missions. A detailed radiative transport code that accounts for the important radiative exchange processes for gaseous mixtures in local thermodynamic and chemical equilibrium is utilized.

  6. Effectiveness of Micro-Blowing Technique in Adverse Pressure Gradients

    NASA Technical Reports Server (NTRS)

    Welch, Gerard E.; Larosiliere, Louis M.; Hwang, Danny P.; Wood, Jerry R.

    2001-01-01

    The impact of the micro-blowing technique (MBT) on the skin friction and total drag of a strut in a turbulent, strong adverse-pressure-gradient flow is assessed experimentally over a range of subsonic Mach numbers (0.3 less than M less than 0.7) and reduced blowing fractions (0 less than or equal to 2F/C (sub f,o) less than or equal to 1.75). The MBT-treated strut is situated along the centerline of a symmetric 2-D diffuser with a static pressure rise coefficient of 0.6. In agreement with presented theory and earlier experiments in zero-pressure-gradient flows, the effusion of blowing air reduces skin friction significantly (e.g., by 60% at reduced blowing fractions near 1.75). The total drag of the treated strut with blowing is significantly lower than that of the treated strut in the limit of zero-blowing; further, the total drag is reduced below that of the baseline (solid-plate) strut, provided that the reduced blowing fractions are sufficiently high. The micro-blowing air is, however, deficient in streamwise momentum and the blowing leads to increased boundary-layer and wake thicknesses and shape factors. Diffuser performance metrics and wake surveys are used to discuss the impact of various levels of micro-blowing on the aerodynamic blockage and loss.

  7. Forebody tangential blowing for control at high angles of attack

    NASA Technical Reports Server (NTRS)

    Kroo, I.; Rock, S.; Roberts, L.

    1991-01-01

    A feasibility study to determine if the use of tangential leading edge blowing over the forebody could produce effective and practical control of the F-18 HARV aircraft at high angles of attack was conducted. A simplified model of the F-18 configuration using a vortex-lattice model was developed to obtain a better understanding of basic aerodynamic coupling effects and the influence of forebody circulation on lifting surface behavior. The effect of tangential blowing was estimated using existing wind tunnel data on normal forebody blowing and analytical studies of tangential blowing over conical forebodies. Incorporation of forebody blowing into the flight control system was investigated by adding this additional yaw control and sideforce generating actuator into the existing F-18 HARV simulation model. A control law was synthesized using LQG design methods that would schedule blowing rates as a function of vehicle sideslip, angle of attack, and roll and yaw rates.

  8. Reducing secondary losses by blowing cold air in a turbine

    NASA Technical Reports Server (NTRS)

    Koschel, W.

    1977-01-01

    Local blowing on the profile suction side of the turbine guide wheel blades can be effective in preventing the propagation of secondary flows that is, the transport of casing and hub boundary layers by pressure gradients. Some preliminary results on how the blowing should be accomplished in order to influence the secondary flows in the desired manner are given. The effectiveness of blowing is demonstrated. Blowing is also seen to be more effective than using boundary layer slots as far as diminishing losses in the rim zones is concerned.

  9. BSDB: the biomolecule stretching database

    PubMed Central

    Sikora, Mateusz; Sułkowska, Joanna I.; Witkowski, Bartłomiej S.; Cieplak, Marek

    2011-01-01

    We describe the Biomolecule Stretching Data Base that has been recently set up at http://www.ifpan.edu.pl/BSDB/. It provides information about mechanostability of proteins. Its core is based on simulations of stretching of 17 134 proteins within a structure-based model. The primary information is about the heights of the maximal force peaks, the force–displacement patterns, and the sequencing of the contact-rupturing events. We also summarize the possible types of the mechanical clamps, i.e. the motifs which are responsible for a protein's resistance to stretching. PMID:20929872

  10. BSDB: the biomolecule stretching database.

    PubMed

    Sikora, Mateusz; Sulkowska, Joanna I; Witkowski, Bartlomiej S; Cieplak, Marek

    2011-01-01

    We describe the Biomolecule Stretching Data Base that has been recently set up at http://www.ifpan.edu.pl/BSDB/. It provides information about mechanostability of proteins. Its core is based on simulations of stretching of 17 134 proteins within a structure-based model. The primary information is about the heights of the maximal force peaks, the force-displacement patterns, and the sequencing of the contact-rupturing events. We also summarize the possible types of the mechanical clamps, i.e. the motifs which are responsible for a protein's resistance to stretching. PMID:20929872

  11. THIRD-GENERATION FOAM BLOWING AGENTS FOR FOAM INSULATION

    EPA Science Inventory

    The report gives results of a study of third-generation blowing agents for foam insulation. (NOTE: the search for third-generation foam blowing agents has led to the realization that, as the number of potential substitutes increases, new concerns, such as their potential to act a...

  12. 1. GENERAL VIEW OF BLOWING ENGINE HOUSE LOOKING NORTH; THREE ...

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

    1. GENERAL VIEW OF BLOWING ENGINE HOUSE LOOKING NORTH; THREE TANKS AT RIGHT ADJACENT TO BUILDING ARE FOR SOFTENING BOILER WATER (LIME TREATMENT): TRUNCATED AND BOILER HOUSE, ONE OVEN AND ORE BRIDGE AT LEFT. - U.S. Steel Corporation, Clairton Works, Blast Furnace Blowing Engine Building, 400 State Street, Clairton, Allegheny County, PA

  13. 74. View of small steam tank used in 'blowing down' ...

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

    74. View of small steam tank used in 'blowing down' or cleaning boilers; in background can be seen the bottom of cylindrical water tank located in setback at southeast corner of blowing engine house. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  14. Use of cooling tower blow down in ethanol fermentation.

    PubMed

    Rajagopalan, N; Singh, V; Panno, B; Wilcoxon, M

    2010-01-01

    Reducing water consumption in bioethanol production conserves an increasingly scarce natural resource, lowers production costs, and minimizes effluent management issues. The suitability of cooling tower blow down water for reuse in fermentation was investigated as a means to lower water consumption. Extensive chemical characterization of the blow down water revealed low concentrations of toxic elements and total dissolved solids. Fermentation carried out with cooling tower blow down water resulted in similar levels of ethanol and residual glucose as a control study using deionized water. The study noted good tolerance by yeast to the specific scale and corrosion inhibitors found in the cooling tower blow down water. This research indicates that, under appropriate conditions, reuse of blow down water from cooling towers in fermentation is feasible. PMID:21076211

  15. Hydraulic fracture during epithelial stretching

    NASA Astrophysics Data System (ADS)

    Casares, Laura; Vincent, Romaric; Zalvidea, Dobryna; Campillo, Noelia; Navajas, Daniel; Arroyo, Marino; Trepat, Xavier

    2015-03-01

    The origin of fracture in epithelial cell sheets subject to stretch is commonly attributed to excess tension in the cells’ cytoskeleton, in the plasma membrane, or in cell-cell contacts. Here, we demonstrate that for a variety of synthetic and physiological hydrogel substrates the formation of epithelial cracks is caused by tissue stretching independently of epithelial tension. We show that the origin of the cracks is hydraulic; they result from a transient pressure build-up in the substrate during stretch and compression manoeuvres. After pressure equilibration, cracks heal readily through actomyosin-dependent mechanisms. The observed phenomenology is captured by the theory of poroelasticity, which predicts the size and healing dynamics of epithelial cracks as a function of the stiffness, geometry and composition of the hydrogel substrate. Our findings demonstrate that epithelial integrity is determined in a tension-independent manner by the coupling between tissue stretching and matrix hydraulics.

  16. Hydraulic fracture during epithelial stretching.

    PubMed

    Casares, Laura; Vincent, Romaric; Zalvidea, Dobryna; Campillo, Noelia; Navajas, Daniel; Arroyo, Marino; Trepat, Xavier

    2015-03-01

    The origin of fracture in epithelial cell sheets subject to stretch is commonly attributed to excess tension in the cells' cytoskeleton, in the plasma membrane, or in cell-cell contacts. Here, we demonstrate that for a variety of synthetic and physiological hydrogel substrates the formation of epithelial cracks is caused by tissue stretching independently of epithelial tension. We show that the origin of the cracks is hydraulic; they result from a transient pressure build-up in the substrate during stretch and compression manoeuvres. After pressure equilibration, cracks heal readily through actomyosin-dependent mechanisms. The observed phenomenology is captured by the theory of poroelasticity, which predicts the size and healing dynamics of epithelial cracks as a function of the stiffness, geometry and composition of the hydrogel substrate. Our findings demonstrate that epithelial integrity is determined in a tension-independent manner by the coupling between tissue stretching and matrix hydraulics. PMID:25664452

  17. Hydraulic fracture during epithelial stretching

    PubMed Central

    Casares, Laura; Vincent, Romaric; Zalvidea, Dobryna; Campillo, Noelia; Navajas, Daniel; Arroyo, Marino; Trepat, Xavier

    2015-01-01

    The origin of fracture in epithelial cell sheets subject to stretch is commonly attributed to excess tension in the cells’ cytoskeleton, in the plasma membrane, or in cell-cell contacts. Here we demonstrate that for a variety of synthetic and physiological hydrogel substrates the formation of epithelial cracks is caused by tissue stretching independently of epithelial tension. We show that the origin of the cracks is hydraulic; they result from a transient pressure build-up in the substrate during stretch and compression maneuvers. After pressure equilibration cracks heal readily through actomyosin-dependent mechanisms. The observed phenomenology is captured by the theory of poroelasticity, which predicts the size and healing dynamics of epithelial cracks as a function of the stiffness, geometry and composition of the hydrogel substrate. Our findings demonstrate that epithelial integrity is determined in a tension-independent manner by the coupling between tissue stretching and matrix hydraulics. PMID:25664452

  18. Laser Blow Off and Impurity Entrainment in CSDX

    NASA Astrophysics Data System (ADS)

    Gosselin, Jordan James; Thakur, Saikat; Tynan, George

    2015-11-01

    Material migration in tokamaks is especially important when considering the lifetime of plasma facing components. However, the flow geometry in the scrape off layer can be complex and diagnostic access is limited. To study the impurity transport in a simple geometry, a laser blow off apparatus was installed on the Controlled Shear Decorelation eXperiment (a 3m long linear helicon source operated plasma machine with an electron temperature of 4 eV and density of 1013 per cm3). The parallel velocity and diffusion coefficients for the impurity are determined by modeling the impurity injection with the 1-D advection-diffusion equation. The parallel velocity of the impurity cloud found with the model agrees very well with laser induced fluorescence (LIF) measurements of the parallel plasma ion velocity. This indicates that the bismuth impurities are fully entrained in the plasma, which is consistent with classical collisional theories. This material is based upon work supported by the U.S. Department of Energy, Office of Science, under Award Number DE-FG02-07ER54912.

  19. Broadband Noise Reduction of a Low-Speed Fan Noise Using Trailing Edge Blowing

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.

    2005-01-01

    An experimental proof-of-concept test was conducted to demonstrate reduction of rotor-stator interaction noise through the use of rotor-trailing edge blowing. The velocity deficit from the viscous wake of the rotor blades was reduced by injecting air into the wake from a continuous trailing edge slot. Hollow blades with interior guide vanes create flow channels through which externally supplied air flows from the blade root to the trailing edge. A previous paper documented the substantial tonal reductions of this Trailing Edge Rotor Blowing (TERB) fan. This report documents the broadband characteristics of TERB. The Active Noise Control Fan (ANCF), located at the NASA Glenn Research Center, was used as the proof-of-concept test bed. Two-component hotwire data behind the rotor, unsteady surface pressures on the stator vane, and farfield directivity acoustic data were acquired at blowing rates of 1.1, 1.5, and 1.8 percent of the total fan mass flow. The results indicate a substantial reduction in the rotor wake turbulent velocity and in the stator vane unsteady surface pressures. Based on the physics of the noise generation, these indirect measurements indicate the prospect of broadband noise reduction. However, since the broadband noise generated by the ANCF is rotor-dominated, any change in the rotor-stator interaction broadband noise levels is barely distinguishable in the farfield measurements.

  20. Experiments in Aircraft Roll-Yaw Control using Forebody Tangential Blowing

    NASA Technical Reports Server (NTRS)

    Pedreiro, Nelson

    1997-01-01

    Advantages of flight at high angles of attack include increased maneuverability and lift capabilities. These are beneficial not only for fighter aircraft, but also for future supersonic and hypersonic transport aircraft during take-off and landing. At high angles of attack the aerodynamics of the vehicle are dominated by separation, vortex shedding and possibly vortex breakdown. These phenomena severely compromise the effectiveness of conventional control surfaces. As a result, controlled flight at high angles of attack is not feasible for current aircraft configurations. Alternate means to augment the control of the vehicle at these flight regimes are therefore necessary. The present work investigates the augmentation of an aircraft flight control system by the injection of a thin sheet of air tangentially to the forebody of the vehicle. This method, known as Forebody Tangential Blowing (FTB), has been proposed as an effective means of increasing the controllability of aircraft at high angles of attack. The idea is based on the fact that a small amount of air is sufficient to change the separation lines on the forebody. As a consequence, the strength and position of the vortices are altered causing a change on the aerodynamic loads. Although a very effective actuator, forebody tangential blowing is also highly non-linear which makes its use for aircraft control very difficult. In this work, the feasibility of using FTB to control the roll-yaw motion of a wind tunnel model was demonstrated both through simulations and experimentally. The wind tunnel model used in the experiments consists of a wing-body configuration incorporating a delta wing with 70-degree sweep angle and a cone-cylinder fuselage. The model is equipped with forebody slots through which blowing is applied. There are no movable control surfaces, therefore blowing is the only form of actuation. Experiments were conducted at a nominal angle of attack of 45 degrees. A unique apparatus that constrains

  1. Intravitreal injection

    MedlinePlus

    Retinal vein occlusion-intravitreal injection; Triamcinolone-intravitreal injection; Dexamethasone-intravitreal injection; Lucentis-intravitreal injection; Avastin-intravitreal injection; Bevacizumab-intravitreal injection; Ranibizumab- ...

  2. Upper surface blowing aerodynamic and acoustic characteristics

    NASA Technical Reports Server (NTRS)

    Ryle, D. M., Jr.; Braden, J. A.; Gibson, J. S.

    1977-01-01

    Aerodynamic performance at cruise, and noise effects due to variations in nacelle and wing geometry and mode of operation are studied using small aircraft models that simulate upper surface blowing (USB). At cruise speeds ranging from Mach .50 to Mach .82, the key determinants of drag/thrust penalties are found to be nozzle aspect ratio, boattailing angle, and chordwise position; number of nacelles; and streamlined versus symmetric configuration. Recommendations are made for obtaining favorable cruise configurations. The acoustic studies, which concentrate on the noise created by the jet exhaust flow and its interaction with wing and flap surfaces, isolate several important sources of USB noise, including nozzle shape, exit velocity, and impingement angle; flow pathlength; and flap angle and radius of curvature. Suggestions for lessening noise due to trailing edge flow velocity, flow pathlength, and flow spreading are given, though compromises between some design options may be necessary.

  3. Bernoulli Suction Effect on Soap Bubble Blowing?

    NASA Astrophysics Data System (ADS)

    Davidson, John; Ryu, Sangjin

    2015-11-01

    As a model system for thin-film bubble with two gas-liquid interfaces, we experimentally investigated the pinch-off of soap bubble blowing. Using the lab-built bubble blower and high-speed videography, we have found that the scaling law exponent of soap bubble pinch-off is 2/3, which is similar to that of soap film bridge. Because air flowed through the decreasing neck of soap film tube, we studied possible Bernoulli suction effect on soap bubble pinch-off by evaluating the Reynolds number of airflow. Image processing was utilized to calculate approximate volume of growing soap film tube and the volume flow rate of the airflow, and the Reynolds number was estimated to be 800-3200. This result suggests that soap bubbling may involve the Bernoulli suction effect.

  4. African Dust Blows over the Caribbean

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Shuttle astronauts frequently track Saharan dust storms as they blow from north Africa across the Atlantic Ocean. Dust palls blowing from Africa take about a week to cross the Atlantic. Recently, researchers have linked Saharan dust to coral disease, allergic reactions in humans, and red tides. The top photograph, a classic image showing African dust over the Caribbean, was taken at a time when few scientists had considered the possibility. The image was taken by Space Shuttle astronauts on July 11, 1994 (STS065-75-47). This photograph looks southwest over the northern edge of a large trans-Atlantic dust plume that blew off the Sahara desert in Africa. In this view, Caicos Island in the Bahamas and the mountainous spines of Haiti are partly obscured by the dust. Closer to the foreground, (about 26 degrees north latitude), the skies are clear. The lower photograph (STS105-723-7) was taken by Space Shuttle astronauts while docked to the International Space Station on August 19, 2001. The spacecraft is over the Atlantic Ocean at roughly 45oN, 60oW. The astronauts were looking obliquely to the south; the boundaries of the dust plumes can be traced visually by the abrupt change from clear to hazy atmosphere-the hazy line marks the northern edge of the dust pall near the Caribbean. Images provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

  5. Hypersonic Boundary Layer Measurements with Variable Blowing Rates Using Molecular Tagging Velocimetry

    NASA Technical Reports Server (NTRS)

    Bathel, Brett F.; Danehy, Paul M.; Johansen, Craig T.; Jones, Stephen B.; Goyne, Christopher P.

    2012-01-01

    Measurements of mean and instantaneous streamwise velocity profiles in a hypersonic boundary layer with variable rates of mass injection (blowing) of nitrogen dioxide (NO2) were obtained over a 10-degree half-angle wedge model. The NO2 was seeded into the flow from a slot located 29.4 mm downstream of the sharp leading edge. The top surface of the wedge was oriented at a 20 degree angle in the Mach 10 flow, yielding an edge Mach number of approximately 4.2. The streamwise velocity profiles and streamwise fluctuating velocity component profiles were obtained using a three-laser NO2->NO photolysis molecular tagging velocimetry method. Observed trends in the mean streamwise velocity profiles and profiles of the fluctuating component of streamwise velocity as functions of the blowing rate are described. An effort is made to distinguish between the effect of blowing rate and wall temperature on the measured profiles. An analysis of the mean velocity profiles for a constant blowing rate is presented to determine the uncertainty in the measurement for different probe laser delay settings. Measurements of streamwise velocity were made to within approximately 120 gm of the model surface. The streamwise spatial resolution in this experiment ranged from 0.6 mm to 2.6 mm. An improvement in the spatial precision of the measurement technique has been made, with spatial uncertainties reduced by about a factor of 2 compared to previous measurements. For the quiescent flow calibration measurements presented, uncertainties as low as 2 m/s are obtained at 95% confidence for long delay times (25 gs). For the velocity measurements obtained with the wind tunnel operating, average single-shot uncertainties of less than 44 m/s are obtained at 95% confidence with a probe laser delay setting of 1 gs. The measurements were performed in the 31-inch Mach 10 Air Tunnel at the NASA Langley Research Center.

  6. Human stretch reflex pathways reexamined

    PubMed Central

    Yavuz, Ş. Utku; Mrachacz-Kersting, Natalie; Sebik, Oğuz; Berna Ünver, M.; Farina, Dario

    2013-01-01

    Reflex responses of tibialis anterior motor units to stretch stimuli were investigated in human subjects. Three types of stretch stimuli were applied (tap-like, ramp-and-hold, and half-sine stretch). Stimulus-induced responses in single motor units were analyzed using the classical technique, which involved building average surface electromyogram (SEMG) and peristimulus time histograms (PSTH) from the discharge times of motor units and peristimulus frequencygrams (PSF) from the instantaneous discharge rates of single motor units. With the use of SEMG and PSTH, the tap-like stretch stimulus induced five separate reflex responses, on average. With the same single motor unit data, the PSF technique indicated that the tap stimulus induced only three reflex responses. Similar to the finding using the tap-like stretch stimuli, ramp-and-hold stimuli induced several peaks and troughs in the SEMG and PSTH. The PSF analyses displayed genuine increases in discharge rates underlying the peaks but not underlying the troughs. Half-sine stretch stimuli induced a long-lasting excitation followed by a long-lasting silent period in SEMG and PSTH. The increase in the discharge rate, however, lasted for the entire duration of the stimulus and continued during the silent period. The results are discussed in the light of the fact that the discharge rate of a motoneuron has a strong positive linear association with the effective synaptic current it receives and hence represents changes in the membrane potential more directly and accurately than the other indirect measures. This study suggests that the neuronal pathway of the human stretch reflex does not include inhibitory pathways. PMID:24225537

  7. Control of VR-7 Dynamic Stall by Strong Steady Blowing

    NASA Technical Reports Server (NTRS)

    Weaver, D.; McAlister, K. W.; Tso, J.

    2004-01-01

    An experiment was performed in a water tunnel on a Boeing-Vertol VR-7 airfoil to study the effects of tangential blowing over the upper surface. Blowing was applied at the quarter-chord location during sinusoidal pitching oscillations described by alpha = alpha(sub m) + 10 deg sin omega t. Results were obtained for a Reynolds number of 1 x 10(exp 5), mean angles of 10 and 15 deg, reduced frequencies ranging from 0.005 to 0.15, and blowing rates from C(sub mu) = 0.16 to 0.66. Unsteady lift, drag, and pitching moment loads are reported, along with fluorescent-dye flow visualizations. Strong steady blowing was found to prevent the bursting of the leading-edge separation bubble at several test points. When this occurred, the lift was increased significantly, stall was averted, and the shape of the moment response showed a positive damping in pitch. In almost all cases, steady blowing reduced the hysteresis amplitudes present in the loads, but the benefits diminished as the reduced frequency and mean angle of oscillation increased. A limited number of pulsed blowing cases indicated that for low blowing rates, the greatest gains were achieved at F(sup +) = 0.9.

  8. Lift Enhancement Using Pulsed Blowing At Compressible Flow Conditions

    NASA Astrophysics Data System (ADS)

    Hites, Michael; Nagib, Hassan; Sytsma, Brian; Wygnanski, Israel; Seifert, Avi; Bachar, Tomer

    1997-11-01

    Oscillatory wall-jets were introduced through spanwise slots along a NACA 0015 airfoil to establish lift augmentation by the unsteady forcing of the wall layer. Pressure coefficients, lift coefficients, and wake velocity profiles were measured for experiments where the oscillatory blowing momentum coefficient was held constant at various frequencies up to M=0.4. At high angles of attack, it was observed that lift coefficient increased by as much as 80% due to the pulsed blowing and that supercritical flow was detected near the leading edge. Measurements at low angles of attack with the flap set at 20^o (an aft loaded airfoil near cruise conditions) showed that low amplitude pulsed forcing from the flap provided a 27% increasing in lift while steady blowing from the flap reduced lift by as much as 15% even at blowing coefficients as high as 3.5%. Wake profiles showed that not only was the lift enhanced due to the oscillatory blowing, but the drag was reduced, demonstrating the effectiveness of pulsed blowing as a tool to increase lift and reduce drag, especially when compared to the relative ineffectiveness of steady blowing under similar conditions.

  9. Soleus stretch reflex during cycling.

    PubMed

    Grey, M J; Pierce, C W; Milner, T E; Sinkjaer, T

    2001-01-01

    The modulation and strength of the human soleus short latency stretch reflex was investigated by mechanically perturbing the ankle during an unconstrained pedaling task. Eight subjects pedaled at 60 rpm against a preload of 10 Nm. A torque pulse was applied to the crank at various positions during the crank cycle, producing ankle dorsiflexion perturbations of similar trajectory. The stretch reflex was greatest during the power phase of the crank cycle and was decreased to the level of background EMG during recovery. Matched perturbations were induced under static conditions at the same crank angle and background soleus EMG as recorded during the power phase of active pedaling. The magnitude of the stretch reflex was not statistically different from that during the static condition throughout the power phase of the movement. The results of this study indicate that the stretch reflex is not depressed during active cycling as has been shown with the H-reflex. This lack of depression may reflect a decreased susceptibility of the stretch reflex to inhibition, possibly originating from presynaptic mechanisms. PMID:11232549

  10. INTERIOR VIEW SHOWING QBOP FURNACE IN BLOW. OXYGEN AND NATURAL ...

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

    INTERIOR VIEW SHOWING Q-BOP FURNACE IN BLOW. OXYGEN AND NATURAL GAS ARE BLOWN INTO THE FURNACE THROUGH THE TUYERES TO CHARGE 460,000 LBS. OF HOT METAL, 100,000 LBS. OF SCRAP WITH 30,000 LBS. OF LIME. BLOW TIME IS 16 MINUTES. THE TIME TO BLOW AND TAP THE FURNACES OF THE RESULTING 205,000 TONS OF STEEL AND SLAG IS 35 MINUTES. - U.S. Steel, Fairfield Works, Q-Bop Furnace, North of Valley Road & West of Ensley, Pleasant Grove Road, Fairfield, Jefferson County, AL

  11. 46 CFR 162.018-5 - Blow-down adjustment and popping tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Blow-down adjustment and popping tolerance. 162.018-5... Compressed Gas § 162.018-5 Blow-down adjustment and popping tolerance. (a) Safety relief valves shall be so... adjustible blow-down construction shall be adjusted to close after blowing down not more than 5 percent...

  12. 46 CFR 162.018-5 - Blow-down adjustment and popping tolerance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Blow-down adjustment and popping tolerance. 162.018-5... Compressed Gas § 162.018-5 Blow-down adjustment and popping tolerance. (a) Safety relief valves shall be so... adjustible blow-down construction shall be adjusted to close after blowing down not more than 5 percent...

  13. 46 CFR 162.018-5 - Blow-down adjustment and popping tolerance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Blow-down adjustment and popping tolerance. 162.018-5... Compressed Gas § 162.018-5 Blow-down adjustment and popping tolerance. (a) Safety relief valves shall be so... adjustable blow-down construction shall be adjusted to close after blowing down not more than 5 percent...

  14. 46 CFR 162.018-5 - Blow-down adjustment and popping tolerance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 6 2012-10-01 2012-10-01 false Blow-down adjustment and popping tolerance. 162.018-5... Compressed Gas § 162.018-5 Blow-down adjustment and popping tolerance. (a) Safety relief valves shall be so... adjustible blow-down construction shall be adjusted to close after blowing down not more than 5 percent...

  15. Hele-Shaw Experiments on Plume Stretching and Folding

    NASA Astrophysics Data System (ADS)

    Foster, M.; Mays, D. C.; Neupauer, R. M.

    2013-12-01

    Fluid mixing in laminar flow is important in a number of practical applications, including remediation of contaminated groundwater. Recent modeling studies have shown that mixing can be accelerated and amplified by imposing a flow that generates stretching and folding of an injected plume of treatment solution. Stretching and folding, in turn, results from engineered injection and extraction of clean water through an array of wells surrounding the treatment solution. This poster describes a series of experiments whose goal is to demonstrate plume stretching and folding in a Hele-Shaw apparatus. An initial plume of treatment solution is injected into the center of the Hele-Shaw apparatus, which is assumed to represent a zone of contaminated groundwater, with four wells spaced evenly around the treatment solution. In order to spread the treatment solution into the groundwater, the four wells perform a series of infusions and withdrawals that push and pull apart the plume of treatment solution. With the proper steps, it will be shown that the plume can be stretched and folded to greatly increase the reactive interface area between the treatment solution and the contaminated groundwater. Consideration is given to two qualitative differences with respect to previous modeling studies. First, constant volume is required by the no-flow boundary used at the edge of the Hele-Shaw cell; any pump that is withdrawing water must have a complementary pump adding water at the same rate. Second, in these experiments, mixing results from a physical process, namely Taylor dispersion, eliminating the uncertainty resulting from the need to assume dispersion mechanisms in numerical models. Therefore, these experiments further elucidate the benefits and challenges of imposing plume stretching and folding in systems (like aquifers) where dispersion is unavoidable, providing new insight into the required logistics of using this approach in groundwater treatment.

  16. A theory for lateral wing-tip blowing

    NASA Technical Reports Server (NTRS)

    Tavella, D.; Roberts, L.

    1985-01-01

    The concept of lateral blowing consists in utilizing thin jets of air, which are ejected in the spanwise direction from slots at the tips of straight and swept wings, or along the leading edges of delta wings, to generate aerodynamic forces without the assistance of deflecting solid surfaces. For weak intensities of blowing the so-generated forces could be used for roll and lateral control of aircraft. In this work a theory for this concept as applied to straight wings is presented, revealing the analytical relationship between blowing and aerodynamic forces. The approach is based on perturbing the span of an elliptically loaded wing. Scaling laws involving blowing intensity, aspect ratio, and angle of attack are derived and compared with experiments. It is concluded that this concept has potential as a novel roll and lateral control device.

  17. Design of a subsonic airfoil with upstream blowing

    NASA Astrophysics Data System (ADS)

    Il'Inskii, N. B.; Mardanov, R. F.

    2007-10-01

    The problem is solved of designing a symmetric airfoil with upstream blowing opposite to subsonic irrotational steady flow of an inviscid incompressible fluid. The solution relies on Sedov’s idea of a stagnation region developing in the neighborhood of the stagnation point. An iterative solution process is developed, and examples of airfoils are constructed. The numerical results are analyzed, and conclusions are drawn about the effect of blowing parameters on the airfoil geometry and the resultant force acting on the airfoil.

  18. Spatial Scale for Modelling Blowing Snow on the Canadian Prairieis

    NASA Astrophysics Data System (ADS)

    Pomeroy, J. W.; Fang, X.

    2007-12-01

    Blowing snow transports and sometimes sublimates much of the seasonal snowfall in the Prairies of western Canada. Snow redistribution is an important feature of Prairie hydrology as deep snowdrifts provide a source of meltwater to replenish ponds and generate streamflow in this dry region. The spatial distribution of snow water equivalent in the spring is therefore of great interest for Prairie hydrology. A test of the appropriate spatial scale for modelling blowing snow redistribution and sublimation was conducted at St Denis National Wildlife Area in the rolling, internally drained prairie pothole region east of Saskatoon, Saskatchewan, Canada. A LiDAR based DEM and LANDSAT based vegetation map were available for this region. A coupled complex windflow and blowing snow model was run with ~250,000 6 m x 6 m grid cells to produce spatially distributed estimates of seasonal blowing snow transport and sublimation. The calculation was then aggregated, using 7 landscape units that represented the major influences of surface roughness, topography and fetch on blowing snow transport and sublimation. Both the distributed and aggregated simulations described similar end of winter snow water equivalent with substantive redistribution of blowing snow from exposed sparsley vegetated sites across topographic drainage divides to the densely vegetated pothole wetlands. Both simulations also agreed well with snow survey observations. While the distributed calculations provide a fascinating and detailed visual image of the interaction of complex landscapes and blowing snow redistribution and sublimation, it is clear that blowing snow transport and sublimation calculations can be successfully aggregated to the spatial scale of the major landscape units in this environment.

  19. Experiments in aircraft roll-yaw control using forebody tangential blowing

    NASA Astrophysics Data System (ADS)

    Pedreiro, Nelson

    Flight at high angles of attack can provide improved maneuverability for fighter aircraft and increased lift capabilities for future supersonic and hypersonic transport aircraft during take-off and landing. At high angles of attack the aerodynamics of the vehicle are dominated by separation, vortex shedding and breakdown, which compromise the effectiveness of conventional control surfaces. As a result, controlled flight at high angles of attack is not feasible for current aircraft configurations. Alternate means to augment the control of the vehicle at these flight regimes are therefore necessary. In this work, the feasibility of using Forebody Tangential Blowing to control the roll-yaw motion of a wind tunnel model at high angles of attack is demonstrated. The method consists of injecting a thin sheet of air tangentially to the forebody of the vehicle to change the separation lines over the forebody and alter the aerodynamic loads. A unique model was developed that describes the unsteady aerodynamic moments generated by both vehicle motion and the applied blowing. This aerodynamic model is sufficiently detailed to predict transient motion of the wind-tunnel model, and is simple enough to be suitable for control logic design and implementation. Successful closed-loop control was demonstrated experimentally for a delta wing body model with a cone-cylinder fuselage. Experiments were performed at 45 degrees nominal angle of attack. At this condition, the natural motion of the system is divergent. A discrete vortex method was developed to help understand the main physics of the flow. The method correctly captures the interactions between forebody and wing vortices. Moreover, the trends in static loads and flow structure are correctly represented. Flow visualization results revealed the vortical structure of the flow to be asymmetric even for symmetric flight conditions. The effects of blowing, roll and yaw angles on the flow structure were determined. It was shown that

  20. The transient roll moment response due to forebody tangential blowing at high angles of attack

    NASA Astrophysics Data System (ADS)

    Chow, Jonathan Kwokching

    The sustained ability for controlled flight at high angles of attack is desirable for future aircraft. For combat aircraft, enhancing maneuverability is important to increasing its survivability. For future supersonic commercial aircraft, an increase in lift at high angles of attack leads to improved performance during take-offs and landing, and a reduction in noise pollution. However, nonlinear and unsteady phenomena, such as flow separation and vortex shedding dominate the aerodynamics in the high angle of attack regime. These phenomena cause the onset of lateral loads and decrease the effectiveness of conventional control surfaces. For conventional aircraft, controlled flight at high angle of attack is difficult or unfeasible without augmented means of control and a good understanding of their impact on vehicle characteristics and dynamics. The injection of thin sheets of air tangentially to the forebody of the vehicle has been found to be an extremely promising method for augmenting the control of a flight vehicle at high angles of attack. Forebody Tangential Blowing (FTB) allows the flow structure to be altered in a rational manner and increase the controllability of the vehicle under these flight conditions. The feasibility of using FTB to control the roll-yaw motion of flight vehicles has been demonstrated. Existing knowledge of FTB's nonlinear impact on the aerodynamic moment responses is limited. Currently available dynamic models predict the general trends in the behavior but do not capture important transient effects that dominate the responses when small amounts of blowing is used. These transients can be large in comparison to the steady-state values. This thesis summarizes the experimental and theoretical results of an investigation into the transient effects of Forebody Tangential Blowing. The relationship between the aerodynamic roll moment, vortical flowfield, and blowing strength is examined to obtain a fundamental understanding of the physics of

  1. Polypropylenes foam consisting of thermally expandable microcapsule as blowing agent

    NASA Astrophysics Data System (ADS)

    Jeoung, Sun Kyung; Hwang, Ye Jin; Lee, Hyun Wook; Kwak, Sung Bok; Han, In-Soo; Ha, Jin Uk

    2016-03-01

    The structure of thermally expandable microcapsule (TEMs) is consisted of a thermoplastic shell which is filled with liquid hydrocarbon at core. The shell of TEMs becomes soft when the temperature is higher than boiling temperature of liquid hydrocarbon. The shell of TEMs is expanded under the high temperature because the inner pressure of TEMs is increased by vaporization of hydrocarbon core. Therefore, the TEMs are applicable for blowing agents and light weight fillers. In this research, we fabricated the polypropylene (PP) foam by using the TEMs and chemical blowing agents and compared to their physical properties. The density of the specimen was decreased when the contents of chemical blowing agents and TEMs were increased. In addition, the mechanical properties (i.e. tensile strength and impact strength) of specimens were deteriorated with increasing amount of chemical blowing agents and TEMs. However, PP foam produced with TEMs showed higher impact strength than the one with the chemical blowing agent. In order to clarify the dependence of impact strength of PP foam as the blowing agent, the morphology difference of the PP foams was investigated. Expanding properties of PP foams produced with TEMs was changed with TEMs content of PP foams. Processing conditions also influenced the mechanical properties of PP foam containing TEMs.

  2. A Purposeful Dynamic Stretching Routine

    ERIC Educational Resources Information Center

    Leon, Craig; Oh, Hyun-Ju; Rana, Sharon

    2012-01-01

    Dynamic stretching, which involves moving parts of the body and gradually increases range of motion, speed of movement, or both through controlled, sport-specific movements, has become the popular choice of pre-exercise warm-up. This type of warm-up has evolved to encompass several variations, but at its core is the principle theme that preparing…

  3. Three Fresh Exposures, Stretched Color

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This panoramic camera image from NASA's Mars Exploration Rover Opportunity has been processed using a technique known as a decorrelation stretch to exaggerate the colors. The area in the image includes three holes created inside 'Endurance Crater' by Opportunity's rock abrasion tool between sols 143 and 148 (June 18 and June 23, 2004). Because color variations are so subtle in the pictured area, stretched images are useful for discriminating color differences that can alert scientists to compositional and textural variations. For example, without the exaggeration, no color difference would be discernable among the tailings left behind after the grinding of these holes, but in this stretched image, the tailings around 'London' (top) appear more red than those of the other holes ('Virginia,' middle, and 'Cobble Hill,' bottom). Scientists believe that is because the rock abrasion tool sliced through two 'blueberries,' or spherules (visible on the upper left and upper right sides of the circle). When the blades break up these spherules, composed of mostly gray hematite, the result is a bright red powder. In this image, you can see the rock layers that made the team want to grind holes in each identified layer. The top layer is yellowish red, the middle is yellowish green and the lower layer is green. Another advantage to viewing this stretched image is the clear detail of the distribution of the rock abrasion tool tailings (heading down-slope) and the differences in rock texture. This image was created using the 753-, 535- and 432-nanometer filters.

  4. Design of Warped Stretch Transform.

    PubMed

    Mahjoubfar, Ata; Chen, Claire Lifan; Jalali, Bahram

    2015-01-01

    Time stretch dispersive Fourier transform enables real-time spectroscopy at the repetition rate of million scans per second. High-speed real-time instruments ranging from analog-to-digital converters to cameras and single-shot rare-phenomena capture equipment with record performance have been empowered by it. Its warped stretch variant, realized with nonlinear group delay dispersion, offers variable-rate spectral domain sampling, as well as the ability to engineer the time-bandwidth product of the signal's envelope to match that of the data acquisition systems. To be able to reconstruct the signal with low loss, the spectrotemporal distribution of the signal spectrum needs to be sparse. Here, for the first time, we show how to design the kernel of the transform and specifically, the nonlinear group delay profile dictated by the signal sparsity. Such a kernel leads to smart stretching with nonuniform spectral resolution, having direct utility in improvement of data acquisition rate, real-time data compression, and enhancement of ultrafast data capture accuracy. We also discuss the application of warped stretch transform in spectrotemporal analysis of continuous-time signals. PMID:26602458

  5. Design of Warped Stretch Transform

    PubMed Central

    Mahjoubfar, Ata; Chen, Claire Lifan; Jalali, Bahram

    2015-01-01

    Time stretch dispersive Fourier transform enables real-time spectroscopy at the repetition rate of million scans per second. High-speed real-time instruments ranging from analog-to-digital converters to cameras and single-shot rare-phenomena capture equipment with record performance have been empowered by it. Its warped stretch variant, realized with nonlinear group delay dispersion, offers variable-rate spectral domain sampling, as well as the ability to engineer the time-bandwidth product of the signal’s envelope to match that of the data acquisition systems. To be able to reconstruct the signal with low loss, the spectrotemporal distribution of the signal spectrum needs to be sparse. Here, for the first time, we show how to design the kernel of the transform and specifically, the nonlinear group delay profile dictated by the signal sparsity. Such a kernel leads to smart stretching with nonuniform spectral resolution, having direct utility in improvement of data acquisition rate, real-time data compression, and enhancement of ultrafast data capture accuracy. We also discuss the application of warped stretch transform in spectrotemporal analysis of continuous-time signals. PMID:26602458

  6. Design of Warped Stretch Transform

    NASA Astrophysics Data System (ADS)

    Mahjoubfar, Ata; Chen, Claire Lifan; Jalali, Bahram

    2015-11-01

    Time stretch dispersive Fourier transform enables real-time spectroscopy at the repetition rate of million scans per second. High-speed real-time instruments ranging from analog-to-digital converters to cameras and single-shot rare-phenomena capture equipment with record performance have been empowered by it. Its warped stretch variant, realized with nonlinear group delay dispersion, offers variable-rate spectral domain sampling, as well as the ability to engineer the time-bandwidth product of the signal’s envelope to match that of the data acquisition systems. To be able to reconstruct the signal with low loss, the spectrotemporal distribution of the signal spectrum needs to be sparse. Here, for the first time, we show how to design the kernel of the transform and specifically, the nonlinear group delay profile dictated by the signal sparsity. Such a kernel leads to smart stretching with nonuniform spectral resolution, having direct utility in improvement of data acquisition rate, real-time data compression, and enhancement of ultrafast data capture accuracy. We also discuss the application of warped stretch transform in spectrotemporal analysis of continuous-time signals.

  7. Stretching dynamics of semiflexible polymers

    NASA Astrophysics Data System (ADS)

    Obermayer, B.; Hallatschek, O.; Frey, E.; Kroy, K.

    2007-08-01

    We analyze the nonequilibrium dynamics of single inextensible semiflexible biopolymers as stretching forces are applied at the ends. Based on different (contradicting) heuristic arguments, various scaling laws have been proposed for the propagation speed of the backbone tension which is induced in response to stretching. Here, we employ a newly developed unified theory to systematically substantiate, restrict, and extend these approaches. Introducing the practically relevant scenario of a chain equilibrated under some prestretching force fpre that is suddenly exposed to a different external force fext at the ends, we give a concise physical explanation of the underlying relaxation processes by means of an intuitive blob picture. We discuss the corresponding intermediate asymptotics, derive results for experimentally relevant observables, and support our conclusions by numerical solutions of the coarse-grained equations of motion for the tension.

  8. Stretching short DNAs in electrolytes.

    PubMed

    Wang, Jizeng; Fan, Xiaojun; Gao, Huajian

    2006-03-01

    This paper is aimed at a combined theoretical and numerical study of the force-extension relation of a short DNA molecule stretched in an electrolyte. A theoretical formula based on a recent discrete wormlike chain (WLC) model of Kierfeld et al. (Eur Phys. J. E, Vol. 14, pp.17-34, 2004) and the classical OSF mean-field theory on electrostatic stiffening of a charged polymer is numerically verified by a set of Brownian dynamics simulations based on a generalized bead-rod (GBR) model incorporating long-ranged electrostatic interactions via the Debye-Hueckel potential (DH). The analysis indicates that the stretching of a short DNA can be well described as a WLC with a constant effective persistent length. This contrasts the behavior of long DNA chains that are known to exhibit variable persistent lengths depending on the ion concentration levels and force magnitudes. PMID:16711068

  9. Stretching

    MedlinePlus

    ... Fitness Diseases & Conditions Infections Q&A School & Jobs Drugs & Alcohol Staying Safe Recipes En Español Making a Change – Your Personal Plan Hot Topics Meningitis Choosing Your Mood Prescription Drug Abuse Healthy School Lunch Planner How Can I ...

  10. BSDB: the Biomolecule Stretching Database

    NASA Astrophysics Data System (ADS)

    Cieplak, Marek; Sikora, Mateusz; Sulkowska, Joanna I.; Witkowski, Bartlomiej

    2011-03-01

    Despite more than a decade of experiments on single biomolecule manipulation, mechanical properties of only several scores of proteins have been measured. A characteristic scale of the force of resistance to stretching, Fmax , has been found to range between ~ 10 and 480 pN. The Biomolecule Stretching Data Base (BSDB) described here provides information about expected values of Fmax for, currently, 17 134 proteins. The values and other characteristics of the unfolding proces, including the nature of identified mechanical clamps, are available at www://info.ifpan.edu.pl/BSDB/. They have been obtained through simulations within a structure-based model which correlates satisfactorily with the available experimental data on stretching. BSDB also lists experimental data and results of the existing all-atom simulations. The database offers a Protein-Data-Bank-wide guide to mechano-stability of proteins. Its description is provided by a forthcoming Nucleic Acids Research paper. Supported by EC FUNMOL project FP7-NMP-2007-SMALL-1, and European Regional Development Fund: Innovative Economy (POIG.01.01.02-00-008/08).

  11. Numerical study of delta wing leading edge blowing

    NASA Technical Reports Server (NTRS)

    Yeh, David; Tavella, Domingo; Roberts, Leonard

    1988-01-01

    Spanwise and tangential leading edge blowing as a means of controlling the position and strength of the leading edge vortices are studied by numerical solution of the three-dimensional Navier-Stokes equations. The leading edge jet is simulated by defining a permeable boundary, corresponding to the jet slot, where suitable boundary conditions are implemented. Numerical results are shown to compare favorably with experimental measurements. It is found that the use of spanwise leading edge blowing at moderate angle of attack magnifies the size and strength of the leading edge vortices, and moves the vortex cores outboard and upward. The increase in lift primarily comes from the greater nonlinear vortex lift. However, spanwise blowing causes earlier vortex breakdown, thus decreasing the stall angle. The effects of tangential blowing at low to moderate angles of attack tend to reduce the pressure peaks associated with leading edge vortices and to increase the suction peak around the leading edge, so that the integrated value of the surface pressure remains about the same. Tangential leading edge blowing in post-stall conditions is shown to re-establish vortical flow and delay vortex bursting, thus increasing C sub L sub max and stall angle.

  12. Proteus mirabilis interkingdom swarming signals attract blow flies

    PubMed Central

    Ma, Qun; Fonseca, Alicia; Liu, Wenqi; Fields, Andrew T; Pimsler, Meaghan L; Spindola, Aline F; Tarone, Aaron M; Crippen, Tawni L; Tomberlin, Jeffery K; Wood, Thomas K

    2012-01-01

    Flies transport specific bacteria with their larvae that provide a wider range of nutrients for those bacteria. Our hypothesis was that this symbiotic interaction may depend on interkingdom signaling. We obtained Proteus mirabilis from the salivary glands of the blow fly Lucilia sericata; this strain swarmed significantly and produced a strong odor that attracts blow flies. To identify the putative interkingdom signals for the bacterium and flies, we reasoned that as swarming is used by this bacterium to cover the food resource and requires bacterial signaling, the same bacterial signals used for swarming may be used to communicate with blow flies. Using transposon mutagenesis, we identified six novel genes for swarming (ureR, fis, hybG, zapB, fadE and PROSTU_03490), then, confirming our hypothesis, we discovered that fly attractants, lactic acid, phenol, NaOH, KOH and ammonia, restore swarming for cells with the swarming mutations. Hence, compounds produced by the bacterium that attract flies also are utilized for swarming. In addition, bacteria with the swarming mutation rfaL attracted fewer blow flies and reduced the number of eggs laid by the flies. Therefore, we have identified several interkingdom signals between P. mirabilis and blow flies. PMID:22237540

  13. Biaxially Stretched Polycarbonate Film For Capacitors

    NASA Technical Reports Server (NTRS)

    Yen, Shaio-Ping S.; Lowry, Lynn E.; Bankston, Clyde P.

    1992-01-01

    Report describes experiments on effects of biaxial stretching on crystal structures, dielectric properties, and sellected thermal and mechanical properties of biaxially stretched polycarbonate films. Highest stretch ratios produce highest degree of crystallinity, with single crystalline phase and distribution of crystallites more nearly isotropic than uniaxially oriented film. Electrical properties at high temperatures improved.

  14. Preventing Blow up by Convective Terms in Dissipative PDE's

    NASA Astrophysics Data System (ADS)

    Bilgin, Bilgesu; Kalantarov, Varga; Zelik, Sergey

    2016-06-01

    We study the impact of the convective terms on the global solvability or finite time blow up of solutions of dissipative PDEs. We consider the model examples of 1D Burger's type equations, convective Cahn-Hilliard equation, generalized Kuramoto-Sivashinsky equation and KdV type equations. The following common scenario is established: adding sufficiently strong (in comparison with the destabilizing nonlinearity) convective terms to equation prevents the solutions from blowing up in a finite time and makes the considered system globally well-posed and dissipative and for weak enough convective terms the finite time blow up may occur similar to the case, when the equation does not involve convective term. This kind of result has been previously known for the case of Burger's type equations and has been strongly based on maximum principle. In contrast to this, our results are based on the weighted energy estimates which do not require the maximum principle for the considered problem.

  15. SYMBIOTIC STAR BLOWS BUBBLES INTO SPACE

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A tempestuous relationship between an unlikely pair of stars may have created an oddly shaped, gaseous nebula that resembles an hourglass nestled within an hourglass. Images taken with Earth-based telescopes have shown the larger, hourglass-shaped nebula. But this picture, taken with NASA's Hubble Space Telescope, reveals a small, bright nebula embedded in the center of the larger one (close-up of nebula in inset). Astronomers have dubbed the entire nebula the 'Southern Crab Nebula' (He2-104), because, from ground-based telescopes, it looks like the body and legs of a crab. The nebula is several light-years long. The possible creators of these shapes cannot be seen at all in this Wide Field and Planetary Camera 2 image. It's a pair of aging stars buried in the glow of the tiny, central nebula. One of them is a red giant, a bloated star that is exhausting its nuclear fuel and is shedding its outer layers in a powerful stellar wind. Its companion is a hot, white dwarf, a stellar zombie of a burned-out star. This odd duo of a red giant and a white dwarf is called a symbiotic system. The red giant is also a Mira Variable, a pulsating red giant, that is far away from its partner. It could take as much as 100 years for the two to orbit around each other. Astronomers speculate that the interaction between these two stars may have sparked episodic outbursts of material, creating the gaseous bubbles that form the nebula. They interact by playing a celestial game of 'catch': as the red giant throws off its bulk in a powerful stellar wind, the white dwarf catches some of it. As a result, an accretion disk of material forms around the white dwarf and spirals onto its hot surface. Gas continues to build up on the surface until it sparks an eruption, blowing material into space. This explosive event may have happened twice in the 'Southern Crab.' Astronomers speculate that the hourglass-shaped nebulae represent two separate outbursts that occurred several thousand years apart

  16. IDENTIFICATION OF CFC AND HCFC SUBSTITUTES FOR BLOWING POLYURETHANE FOAM INSULATION PRODUCTS

    EPA Science Inventory

    The report gives results of a cooperative effort to identiry chlorofluorocarbons and hydrochlorofluorocarbon substitutes for blowing polyurethane foam insulation products. The substantial ongoing effort is identifying third-generation blowing agets for polyurethane foams to repla...

  17. Blow-up behavior of positive solutions for a chemical fuel ignition device model

    SciTech Connect

    Jia, Yunfeng; Wu, Jianhua; Xu, Hong-Kun

    2014-04-15

    Blow-up behavior of positive solutions of a semi-linear parabolic system arising from thermal explosion, which subject to the homogenous Dirichlet boundary conditions, is investigated. In particular, sufficient conditions for the solutions to blow up are obtained.

  18. Detachment of stretched viscoelastic fibrils

    NASA Astrophysics Data System (ADS)

    Glassmaker, N. J.; Hui, C. Y.; Yamaguchi, T.; Creton, C.

    2008-03-01

    New experimental results are presented about the final stage of failure of soft viscoelastic adhesives. A microscopic view of the detachment of the adhesive shows that after cavity growth and expansion, well adhered soft adhesives form a network of fibrils connected to expanded contacting feet which fail via a sliding mechanism, sensitive to interfacial shear stresses rather than by a fracture mechanism as sometimes suggested in earlier work. A mechanical model of this stretching and sliding failure phenomenon is presented which treats the fibril as a nonlinear elastic or viscoelastic rod and the foot as an elastic layer subject to a friction force proportional to the local displacement rate. The force on the stretched rod drives the sliding of the foot against the substrate. The main experimental parameter controlling the failure strain and stress during the sliding process is identified by the model as the normalized probe pull speed, which also depends on the magnitude of the friction and PSA modulus. In addition, the material properties, viscoelasticity and finite extensibility of the polymer chains, are shown to have an important effect on both the details of the sliding process and the ultimate failure strain and stress. Appendix B is only available in electronic form at 10.1140/epje/i2007-10287-y and are accessible for authorised users.

  19. The study of poly(L-lactide) grafted silica nanoparticles on the film blowing of poly(L-lactide)

    NASA Astrophysics Data System (ADS)

    Wu, Feng; Liu, Zhengying; Yang, Mingbo

    2015-05-01

    PLA nanocomposites are prepared by us, and to better develop the function of silica nanoparticle, the surface of silica nanoparticles are modified by introducing PLA chains via "grafting to" method in our research. According to the results of 1H NMR and TGA, it shows that the PLA grafted Silica nanoparticles are successfully synthesized by controlling the reaction condition, and the molecular weight of the grafted PLA chains is relatively as high as 22 400 g/mol. PLA Nanocomposites with modified nanoparticles are prepared using a convenient melt blending method to guarantee well-distribution of the particles. The well-dispersion state of silica nanospheres is confirmed by Scan Electrical Micrograph (SEM) technology. From the dynamic shear rheology tests, the strain and time sweep both reveal that stability networks are formed in these nanocomposites. And the frequency sweep shows that the nanoparticles with long grafted chains dramatically enhanced the storage and viscosity of the pure PLA. The rheology testing suggests that strong particle-matrix interactions between molecularly/nano-level dispersed grafted silica and PLA chains formed; and the elongational viscosity of PLA has been markedly improved with the addition of the nanoparticle. The effect of modified nanoparticles on the thermal properties of PLA has also been studied by us using Differential Scanning Calorimetry (DSC). It reveals that the crystallization rate of PLA has been improved as the long grafted chains play as the nucleation sites for PLA. Finally based on these rheology and crystallization researches, the nanocomposites are used to prepare PLA blowing films. Compared to pure PLA and PLA/unmodified silica nanocomposites, the results show that the stability of the film blowing has been greatly improved and the blow-up ratio has been increased with the addition of PLA grafted nanoparticles. The modified nanoparticles hold significant candidates to improve the thermal stability and the

  20. PLA fibers with antimicrobial properties developed by solution blow spinning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present work reports on the development and characterization of novel Poly(lactic acid) hybrid fibers with antimicrobial properties produced by solution blow spinning. This technique presents additional advantages over conventional electrospinning, such as reduced cost and higher rate of fiber p...

  1. 42. NORTHEAST VIEW OF BLOW ENGINE HOUSE No. 3, WITH ...

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

    42. NORTHEAST VIEW OF BLOW ENGINE HOUSE No. 3, WITH FILTER CAKE HOSUE IN CENTER FOREGROUND, AND EVAPORATIVE WASTE WATER TREATMENT COOLING TOWER TO THE LEFT. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  2. Seismotectonic implications of sand blows in the southern Mississippi Embayment

    USGS Publications Warehouse

    Cox, R.T.; Hill, A.A.; Larsen, D.; Holzer, T.; Forman, S.L.; Noce, T.; Gardner, C.; Morat, J.

    2007-01-01

    We explore seismically-induced sand blows from the southern Mississippi Embayment and their implications in resolving the question of near or distal epicentral source region. This was accomplished using aerial photography, field excavations, and cone penetration tests. Our analysis shows that three sand blow fields exhibit a distinct chronology of strong ground motion for the southern embayment: (1) The Ashley County, Arkansas sand blow field, near the Arkansas/Louisiana state border, experienced four Holocene sand venting episodes; (2) to the north, the Desha County field experienced at least three episodes of liquefaction; and (3) the Lincoln-Jefferson Counties field experienced at least one episode. Cone penetration tests (CPT) conducted in and between the sand blow fields suggest that the fields may not be distal liquefaction associated with New Madrid seismic zone earthquakes but rather are likely associated with strong earthquakes on local faults. This conclusion is consistent with the differences in timing of the southern embayment sand venting episodes and those in the New Madrid seismic zone. These results suggest that active tectonism and strong seismicity in intraplate North America may not be localized at isolated weak spots, but rather widespread on fault systems that are favorably oriented for slip in the contemporary stress field. ?? 2006 Elsevier B.V. All rights reserved.

  3. A Blowing Snow Model for Ice Shelf Rifts

    NASA Astrophysics Data System (ADS)

    Leonard, K. C.; Tremblay, L.; Macayeal, D. R.

    2005-12-01

    Ice melange (a mixture of snow, marine ice, and ice talus) may play various roles in the rates of propagation of iceberg-calving rifts through Antarctic ice shelves. This modeling study examines the role of windblown snow in the formation and maintenance of ice melange in the "nascent rift" in the Ross Ice Shelf (78 08'S, 178 29'W). The rift axis is perpendicular to the regional wind direction, allowing us to employ a two-dimensional blowing snow model. The Piektuk-Tuvaq blowing snow model (Dery and Tremblay, 2004) adapted the Piektuk blowing snow model for use in sea ice environments by including parameterization for open-water leads within the sea ice. This version of the model was used to study the initial conditions of a freshly-opened rift, as the input of blowing snow into the seawater within the rift promotes marine ice formation by cooling and freshening the surface water. We adapted the Piektuk-Tuvaq model both for the local climatic conditions and to incorporate the geometry of the rift, which is 30m deep and 100m wide (far deeper than a lead). We present the evolution of the topography within the rift for two cases. The first is an ice melange composed exclusively of snow and marine ice, the second uses an initial topography including large chunks of ice talus.

  4. Reduction of airfoil trailing edge noise by trailing edge blowing

    NASA Astrophysics Data System (ADS)

    Gerhard, T.; Erbslöh, S.; Carolus, T.

    2014-06-01

    The paper deals with airfoil trailing edge noise and its reduction by trailing edge blowing. A Somers S834 airfoil section which originally was designed for small wind turbines is investigated. To mimic realistic Reynolds numbers the boundary layer is tripped on pressure and suction side. The chordwise position of the blowing slot is varied. The acoustic sources, i.e. the unsteady flow quantities in the turbulent boundary layer in the vicinity of the trailing edge, are quantified for the airfoil without and with trailing edge blowing by means of a large eddy simulation and complementary measurements. Eventually the far field airfoil noise is measured by a two-microphone filtering and correlation and a 40 microphone array technique. Both, LES-prediction and measurements showed that a suitable blowing jet on the airfoil suction side is able to reduce significantly the turbulence intensity and the induced surface pressure fluctuations in the trailing edge region. As a consequence, trailing edge noise associated with a spectral hump around 500 Hz could be reduced by 3 dB. For that a jet velocity of 50% of the free field velocity was sufficient. The most favourable slot position was at 90% chord length.

  5. 39. SOUTHERN INTERIOR VIEW OF BLOW ENGINE HOUSE No. 2 ...

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

    39. SOUTHERN INTERIOR VIEW OF BLOW ENGINE HOUSE No. 2 WITH THE STEAM TURBINE BLADES OF AXIAL TURBOBLOWER No. 4. THE STATOR BLADES OF AXIAL TURBOBLOWER No. 4. THE STATOR BLADES AT THE COMPRESSOR END OF AXIAL TURBOBLOWER No. 4 ARE IN THE BACKGROUND. (Martin Stupich) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  6. CR-39 track etching and blow-up method

    DOEpatents

    Hankins, Dale E.

    1987-01-01

    This invention is a method of etching tracks in CR-39 foil to obtain uniformly sized tracks. The invention comprises a step of electrochemically etching the foil at a low frequency and a "blow-up" step of electrochemically etching the foil at a high frequency.

  7. Blow-Out Fracture due to a Hazel Stick Beat.

    PubMed

    Erbilen, Esin; Yuksel, Harun; Onder, H Ibrahim; Tunc, Murat; Kaya, Murat

    2008-12-01

    The aim of this case report is to demonstrate that blow-out fractures can occur not only by a classical trauma mechanism but also from the consequences of a stick beat. A 66-year-old male was admitted to our hospital complaining of a sudden swelling of his right eyelid after blowing his nose. In his medical history there was the report of a hazel stick beat the previous day. Upon ophthalmological examination, ecchymosis was observed in the right orbital region, and subcutaneous amphisema in addition to a dense subconjunctival hemorrhage were detected. Using computed tomography (CT), the intraorbital air density in the soft tissues and the right maxillary sinus wall fracture possessing fluid density compatible with hemorrhage was observed. The patient was treated conservatively with prednisolone and antibiotics. We conclude that a blow-out fracture may occur in patients who experience orbital trauma, even in cases of low-energy trauma. These patients may be symptomatic after an episode of hard nose-blowing. PMID:25610052

  8. Proteus mirabilis interkingdom swarming signals attract blow flies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flies transport specific bacteria with their larvae which provides a wider range of nutrients for those bacteria. Our hypothesis was that this symbiotic interaction may depend on interkingdom signaling. We obtained Proteus mirabilis from the salivary glands of the blow fly Lucilia sericat. This s...

  9. 67. View looking east up walkway between blowing engine house ...

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

    67. View looking east up walkway between blowing engine house at left and boilers at right showing base of stack for boilers No. 5 and 6. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  10. Whistle-Blowing and the Code of Silence in Police Agencies: Policy and Structural Predictors

    ERIC Educational Resources Information Center

    Rothwell, Gary R.; Baldwin, J. Norman

    2007-01-01

    This article reports the findings from a study that investigates predictors of police willingness to blow the whistle and police frequency of blowing the whistle on seven forms of misconduct. It specifically investigates the capacity of nine policy and structural variables to predict whistle-blowing. The results indicate that two variables, a…

  11. Decorrelation Stretch Near Cerberus Fossae

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released July 25, 2004 On this image you can see two infrared frames of the same area on Mars. One of the images (in black and white) represents a single wavelength or band of the THEMIS IR instrument, while the other image (in false color) represents 3 different bands. The image with the various colors was created with a technique called Decorrelation Stretch (DCS). In this technique individual bands of the THEMIS IR instrument are stretched to better show compositional variations throughout the whole range. After the bands are stretched they are overlayed on one another and colors are assigned to each band. This makes up the colors in the image.

    As you can see, there is a difference in what is noticable in the single band IR image versus the false-colored one. On the color image the pink/magenta colors usually represent basaltic content, cyan often indicates the presence of water ice clouds, while green can represent dust.

    The bright purple and pink colors associated with the valley are due to basalt. There may be a thin veneer of dust present in the region (it was a dark colored region during the Viking mission in the 1970's) through which the basaltic material pokes out along the edges of the valley and the nearby knobby terrain.

    Image information: IR instrument. Latitude 10.7, Longitude 163 East (197 West). 100 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA

  12. Cell reorientation under cyclic stretching.

    PubMed

    Livne, Ariel; Bouchbinder, Eran; Geiger, Benjamin

    2014-01-01

    Mechanical cues from the extracellular microenvironment play a central role in regulating the structure, function and fate of living cells. Nevertheless, the precise nature of the mechanisms and processes underlying this crucial cellular mechanosensitivity remains a fundamental open problem. Here we provide a novel framework for addressing cellular sensitivity and response to external forces by experimentally and theoretically studying one of its most striking manifestations--cell reorientation to a uniform angle in response to cyclic stretching of the underlying substrate. We first show that existing approaches are incompatible with our extensive measurements of cell reorientation. We then propose a fundamentally new theory that shows that dissipative relaxation of the cell's passively-stored, two-dimensional, elastic energy to its minimum actively drives the reorientation process. Our theory is in excellent quantitative agreement with the complete temporal reorientation dynamics of individual cells measured over a wide range of experimental conditions, thus elucidating a basic aspect of mechanosensitivity. PMID:24875391

  13. Cell reorientation under cyclic stretching

    NASA Astrophysics Data System (ADS)

    Livne, Ariel; Bouchbinder, Eran; Geiger, Benjamin

    2014-05-01

    Mechanical cues from the extracellular microenvironment play a central role in regulating the structure, function and fate of living cells. Nevertheless, the precise nature of the mechanisms and processes underlying this crucial cellular mechanosensitivity remains a fundamental open problem. Here we provide a novel framework for addressing cellular sensitivity and response to external forces by experimentally and theoretically studying one of its most striking manifestations—cell reorientation to a uniform angle in response to cyclic stretching of the underlying substrate. We first show that existing approaches are incompatible with our extensive measurements of cell reorientation. We then propose a fundamentally new theory that shows that dissipative relaxation of the cell’s passively-stored, two-dimensional, elastic energy to its minimum actively drives the reorientation process. Our theory is in excellent quantitative agreement with the complete temporal reorientation dynamics of individual cells measured over a wide range of experimental conditions, thus elucidating a basic aspect of mechanosensitivity.

  14. Stagnation region gas film cooling: Spanwise angled injection from multiple rows of holes. [gas turbine engines

    NASA Technical Reports Server (NTRS)

    Luckey, D. W.; Lecuyer, M. R.

    1981-01-01

    The stagnation region of a cylinder in a cross flow was used in experiments conducted with both a single row and multiple rows of spanwise angled (25 deg) coolant holes for a range of the coolant blowing ratio with a freestream to wall temperature ratio approximately equal to 1.7 and R(eD) = 90,000. Data from local heat flux measurements are presented for injection from a single row located at 5 deg, 22.9 deg, 40.8 deg, 58.7 deg from stagnation using a hole spacing ratio of S/d(o) = 5 and 10. Three multiple row configurations were also investigated. Data are presented for a uniform blowing distribution and for a nonuniform blowing distribution simulating a plenum supply. The data for local Stanton Number reduction demonstrated a lack of lateral spreading by the coolant jets. Heat flux levels larger than those without film cooling were observed directly behind the coolant holes as the blowing ratio exceeded a particular value. The data were spanwise averaged to illustrate the influence of injection location, blowing ratio and hole spacing. The large values of blowing ratio for the blowing distribution simulating a plenum supply resulted in heat flux levels behind the holes in excess of the values without film cooling. An increase in freestream turbulence intensity from 4.4 to 9.5 percent had a negligible effect on the film cooling performance.

  15. Boundary layer flow of nanofluid over an exponentially stretching surface

    PubMed Central

    2012-01-01

    The steady boundary layer flow of nanofluid over an exponential stretching surface is investigated analytically. The transport equations include the effects of Brownian motion parameter and thermophoresis parameter. The highly nonlinear coupled partial differential equations are simplified with the help of suitable similarity transformations. The reduced equations are then solved analytically with the help of homotopy analysis method (HAM). The convergence of HAM solutions are obtained by plotting h-curve. The expressions for velocity, temperature and nanoparticle volume fraction are computed for some values of the parameters namely, suction injection parameter α, Lewis number Le, the Brownian motion parameter Nb and thermophoresis parameter Nt. PMID:22289390

  16. HOLOCENE AND LATE PLEISTOCENE(? ) EARTHQUAKE-INDUCED SAND BLOWS IN COASTAL SOUTH CAROLINA.

    USGS Publications Warehouse

    Obermeier, S.F.; Jacobson, R.B.; Powars, D.S.; Weems, R.E.; Hallbick, D.C.; Gohn, G.S.; Markewich, H.W.

    1986-01-01

    Multiple generations of prehistoric sand blows, interpreted as earthquake induced, have been discovered throughout coastal South Carolina. These sand blows extend far beyond 1886 earthquake induced sand blows, in sediments having approximately the same liquefaction susceptibility. The seismic source zone for the prehistoric sand blows is unknown. The different distributions of prehistoric and 1886 sand blows have two possible explanations: (1) moderate to strong earthquakes originated in different seismic source locations through time or (2) at least one earthquake much stronger than the 1886 event also originated from the same seismic source as the 1886 earthquake.

  17. Golimumab Injection

    MedlinePlus

    ... it.Golimumab injection comes in prefilled syringes and auto-injection devices for subcutaneous injection. Use each syringe ... method.Do not remove the cap from the auto-injection device or the cover from the prefilled ...

  18. Blow-by gas processing arrangement for automotive internal combustion engines

    SciTech Connect

    Anno, N.; Arai, T.

    1987-07-21

    This patent describes a blow-by gas processing arrangement for an internal combustion engine, comprising: a cylinder block having a chamber for collecting a blow-by gas, a blow-by gas passage communicating with the chamber, and spaced journal walls for supporting a crankshaft; a relatively large oil mist separating passage defined in the cylinder block and laterally extending into one of the journal walls beyond the blow-by gas passage. The oil mist separates passage communicating with the blow-by gas passage for preliminary separating an oil mist from the blow-by gas supplied from the chamber; an oil separator communicating with the oil mist separates passage for separating an oil mist from the blow-by gas supplied from the oil mist separating passage; and a PCV valve is connected to the oil mist separator; and an intake manifold connected to the PCV valve.

  19. An assessment of upper surface blowing for the reduction of tilt rotor download

    NASA Technical Reports Server (NTRS)

    Faye, Robert E.; Felker, Fort F.; Light, Jeffrey S.

    1987-01-01

    A study evaluating the use of upper-surface blowing to reduce the wing download on a V-22 tilt rotor aircraft has been completed. The study assesses the penalties associated with the upper-surface blowing system (compressor weight, compressor power, etc.), and the reduction in wing download, for a wide range of blowing slot heights and blowing pressure ratios. Three wing configurations were investigated: blowing at both leading and trailing edges with no change in wing planform relative to the V-22 tilt rotor aircraft, blowing at both leading and trailing edges with a 25% reduction in wing chord, and blowing at the leading edge only with the flap deflected 75 deg. Predicted download is presented for all of these configurations, and is compared with the download of the baseline V-22 tilt rotor aircraft configuration. The optimum configuration had 15% less net download than the baseline V-22 configuration.

  20. Reinforcement for Stretch Formed Sheet Metal

    NASA Technical Reports Server (NTRS)

    Lea, J. B.; Baxter, C. R.

    1983-01-01

    Tearing of aluminum sheet metal durinng stretch forming prevented by flame spraying layer of aluminum on edges held in stretch-forming machine. Technique improves grip of machine on metal and reinforced sheet better able to with stand concentration of force in vicinity of grips.

  1. Stator Loading Measurements Behind a Fan With Trailing Edge Blowing

    NASA Technical Reports Server (NTRS)

    Waitz, Ian A.

    2000-01-01

    The problem of aircraft noise pollution around airports has become increasingly important as those areas have become more densely populated. Currently, the removal of older noisier aircraft from operation is reducing noise levels around airports; however, with air traffic projected to increase by about 5% over the next decade the number of commercial aircraft operating in the world is expected to be about 17,700 by the year 2007. To keep noise levels around airports from increasing as a result of traffic increases, it is important to investigate new methods of noise reduction. The objective of this work is to provide a better understanding of the effects that trailing edge blowing has on stator unsteady loading. This is done by presenting flowfield and stator loading data from experiments conducted with and without trailing edge blowing.

  2. Effect of Blowing on Boundary Layer of Scarf Inlet

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Clark, Lorenzo R.

    2004-01-01

    When aircraft operate in stationary or low speed conditions, airflow into the engine accelerates around the inlet lip and pockets of turbulence that cause noise and vibration can be ingested. This problem has been encountered with engines equipped with the scarf inlet, both in full scale and in model tests, where the noise produced during the static test makes it difficult to assess the noise reduction performance of the scarf inlet. NASA Langley researchers have implemented boundary layer control in an attempt to reduce the influence of the flow nonuniformity in a 12-in. diameter model of a high bypass fan engine mounted in an anechoic chamber. Static pressures and boundary layer profiles were measured in the inlet and far field acoustic measurements were made to assess the effectiveness of the blowing treatment. The blowing system was found to lack the authority to overcome the inlet distortions. Methods to improve the implementation of boundary layer control to reduce inlet distortion are discussed.

  3. Intraguild predation influences oviposition behavior of blow flies (Diptera: Calliphoridae).

    PubMed

    Galindo, Luciane A; Moral, Rafael A; Moretti, Thiago C; Godoy, Wesley A C; Demétrio, Clarice G B

    2016-05-01

    The objective of the present study was to determine whether blow flies (Diptera: Calliphoridae) are able to identify larvae of an intraguild predator species in the substrate and avoid laying eggs there. Blow flies oviposited in traps with different treatments: substrate only and substrate with larvae of Chrysomya albiceps (Wiedemann, 1819), Chrysomya megacephala (Fabricius, 1794), or Chrysomya putoria (Wiedemann, 1830). Ch. megacephala, Ch. putoria, and Lucilia eximia (Wiedemann, 1819) avoided laying eggs in the trap containing Ch. albiceps larvae. Cochliomyia macellaria (Fabricius, 1775) did not oviposit differently in each substrate but had overall low abundance. The prevalence of species on corpses may be influenced by the ability of the species to detect the presence of other species, mainly predators. In this sense, intraguild predation may result in misinterpretations of a crime scene and should be considered when assessing the minimum postmortem interval. PMID:26888288

  4. Computational investigation of slot blowing for fuselage forebody flow control

    NASA Technical Reports Server (NTRS)

    Murman, Scott M.; Rizk, Yehia M.; Schiff, Lewis B.; Cummings, Russell M.

    1992-01-01

    This paper presents a computational investigation of a tangential slot blowing concept for generating lateral control forces on an aircraft fuselage forebody. The effects of varying both the jet width and jet exit velocity for a fixed location slot are analyzed. This work is aimed at aiding researchers in designing future experimental and computational models of tangential slot blowing. The primary influence on the resulting side force of the forebody is seen to be the jet mass flow rate. This influence is sensitive to different combinations of slot widths and jet velocities over the range of variables considered. Both an actuator plane and an overset grid technique are used to model the tangential slot. The overset method successfully resolves the details of the actual slot geometry, extending the generality of the numerical method. The actuator plane concept predicts side forces similar to those produced by resolving the actual slot geometry.

  5. Lift augmentation via spanwise tip blowing - A numerical study

    NASA Technical Reports Server (NTRS)

    Childs, R. E.

    1986-01-01

    Numerical simulations of a low aspect ratio wing with and without a spanwise directed jet issuing from the wing tip have been performed. The results show that the tip vortex is displaced outward and upward by the blowing. This gives rise to a local lift augmentation mechanism, vortex lift caused by the vortex core being above the wing, and a global mechanism, the reduction of induced velocities due to greater apparent spin.

  6. A theoretical investigation of over-wing-blowing aerodynamics

    NASA Technical Reports Server (NTRS)

    Lan, C. E.

    1976-01-01

    A theoretical method is established for determining the aerodynamic characteristics of over-wing-blowing configurations. The method accounts for both jet entrainment and jet interaction effects because of the differences in freestream and jet dynamic pressures and Mach numbers. The predicted lift increments agree well with available data. It is shown that the lift is underpredicted with entrainment effect alone when the jet is close to the wing surface.

  7. Strategy as stretch and leverage.

    PubMed

    Hamel, G; Prahalad, C K

    1993-01-01

    Global competition is not just product versus product or company versus company. It is mind-set versus mind-set. Driven to understand the dynamics of competition, we have learned a lot about what makes one company more successful than another. But to find the root of competitiveness--to understand why some companies create new forms of competitive advantage while others watch and follow--we must look at strategic mind-sets. For many managers, "being strategic" means pursuing opportunities that fit the company's resources. This approach is not wrong, Gary Hamel and C.K. Prahalad contend, but it obscures an approach in which "stretch" supplements fit and being strategic means creating a chasm between ambition and resources. Toyota, CNN, British Airways, Sony, and others all displaced competitors with stronger reputations and deeper pockets. Their secret? In each case, the winner had greater ambition than its well-endowed rivals. Winners also find less resource-intensive ways of achieving their ambitious goals. This is where leverage complements the strategic allocation of resources. Managers at competitive companies can get a bigger bang for their buck in five basic ways: by concentrating resources around strategic goals; by accumulating resources more efficiently; by complementing one kind of resource with another; by conserving resources whenever they can; and by recovering resources from the market-place as quickly as possible. As recent competitive battles have demonstrated, abundant resources can't guarantee continued industry leadership.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:10124635

  8. Mars Under the Microscope (stretched)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This magnified look at the martian soil near the Mars Exploration Rover Opportunity's landing site, Meridiani Planum, shows coarse grains sprinkled over a fine layer of sand. The image was captured on the 10th day, or sol, of the rover's mission by its microscopic imager, located on the instrument deployment device, or 'arm.' Scientists are intrigued by the spherical rocks, which can be formed by a variety of geologic processes, including cooling of molten lava droplets and accretion of concentric layers of material around a particle or 'seed.'

    The examined patch of soil is 3 centimeters (1.2 inches) across. The circular grain in the lower left corner is approximately 3 millimeters (.12 inches) across, or about the size of a sunflower seed.

    This stretched color composite was obtained by merging images acquired with the orange-tinted dust cover open and closed. The varying hints of orange suggest differences in mineral composition. The blue tint at the lower right corner is a tag used by scientists to indicate that the dust cover is closed.

  9. L-Type Calcium Channels Do Not Play a Critical Role in Chest Blow Induced Ventricular Fibrillation: Commotio Cordis

    PubMed Central

    Madias, Christopher; Garlitski, Ann C.; Kalin, John; Link, Mark S.

    2016-01-01

    Background. In a commotio cordis swine model, ventricular fibrillation (VF) can be induced by a ball blow to the chest believed secondary to activation of mechanosensitive ion channels. The purpose of the current study is to evaluate whether stretch induced activation of the L-type calcium channel may cause intracellular calcium overload and underlie the VF in commotio cordis. Method and Results. Anesthetized juvenile swine received 6 chest wall strikes with a 17.9 m/s lacrosse ball timed to the vulnerable period for VF induction. Animals were randomized to IV verapamil (n = 6) or placebo (n = 6). There was no difference in the observed frequency of VF between verapamil (19/26: 73%) and placebo (20/36: 56%) treated animals (p = 0.16). There was also no significant difference in the combined endpoint of VF or nonsustained VF (21/26: 81% in verapamil versus 24/36: 67% in controls, p = 0.22). Conclusions. In this experimental model of commotio cordis, verapamil did not prevent VF induction. Thus, in commotio cordis it is unlikely that stretch activation of the L-type calcium channel with resultant intracellular calcium overload plays a prominent role. PMID:26925288

  10. An implicit finite-difference solution to the viscous shock layer, including the effects of radiation and strong blowing

    NASA Technical Reports Server (NTRS)

    Garrett, L. B.; Smith, G. L.; Perkins, J. N.

    1972-01-01

    An implicit finite-difference scheme is developed for the fully coupled solution of the viscous, radiating stagnation-streamline equations, including strong blowing. Solutions are presented for both air injection and injection of carbon-phenolic ablation products into air at conditions near the peak radiative heating point in an earth entry trajectory from interplanetary return missions. A detailed radiative-transport code that accounts for the important radiative exchange processes for gaseous mixtures in local thermodynamic and chemical equilibrium is utilized in the study. With minimum number of assumptions for the initially unknown parameters and profile distributions, convergent solutions to the full stagnation-line equations are rapidly obtained by a method of successive approximations. Damping of selected profiles is required to aid convergence of the solutions for massive blowing. It is shown that certain finite-difference approximations to the governing differential equations stabilize and improve the solutions. Detailed comparisons are made with the numerical results of previous investigations. Results of the present study indicate lower radiative heat fluxes at the wall for carbonphenolic ablation than previously predicted.

  11. Spatial and temporal variations of blowing dust events in the Taklimakan Desert

    NASA Astrophysics Data System (ADS)

    Yang, Xinghua; Shen, Shuanghe; Yang, Fan; He, Qing; Ali, Mamtimin; Huo, Wen; Liu, Xinchun

    2016-08-01

    The Taklimakan Desert is the source of most blowing dust events in China. However, previous studies of sandstorms in this region have not included data from the inner desert because of the difficulty in making observations in this area. In this study, the spatial and temporal variations of blowing dust events, including sandstorms and blowing sand, and its relations with climatic parameters in the Taklimakan Desert were analyzed using data from ten desert-edge meteorological stations during 1961 to 2010 and two inner-desert meteorological stations during 1988 to 1990, 1996 to 2010, and 1992 to 2010. The results identified two regions (Pishan-Hotan-Minfeng and Xiaotang-Tazhong) where blowing dust events occur on average more than 80 days per year. The regions with the highest occurrence of sandstorms, blowing sand, and blowing dust events were different, with sandstorms centered in the north of the desert (Xiaotang, 46.9 days), whereas the central location for blowing sand (Pishan, 86.4 days) and blowing dust events (Minfeng, 113.5 days) activity was located at the southwestern and southern edges of the desert, respectively. The occurrence of sandstorms generally decreased from 1961 to 2010, while the occurrence of blowing sand increased from 1961 to 1979 and then generally decreased. The temporal variation of blowing dust events was mainly affected by the occurrence of strong wind and daily temperature, with average correlation coefficients of 0.46 and -0.41 for these variables across the whole desert.

  12. Stretch induced hyperexcitability of mice callosal pathway

    PubMed Central

    Fan, Anthony; Stebbings, Kevin A.; Llano, Daniel A.; Saif, Taher

    2015-01-01

    Memory and learning are thought to result from changes in synaptic strength. Previous studies on synaptic physiology in brain slices have traditionally been focused on biochemical processes. Here, we demonstrate with experiments on mouse brain slices that central nervous system plasticity is also sensitive to mechanical stretch. This is important, given the host of clinical conditions involving changes in mechanical tension on the brain, and the normal role that mechanical tension plays in brain development. A novel platform is developed to investigate neural responses to mechanical stretching. Flavoprotein autofluoresence (FA) imaging was employed for measuring neural activity. We observed that synaptic excitability substantially increases after a small (2.5%) stretch was held for 10 min and released. The increase is accumulative, i.e., multiple stretch cycles further increase the excitability. We also developed analytical tools to quantify the spatial spread and response strength. Results show that the spatial spread is less stable in slices undergoing the stretch-unstretch cycle. FA amplitude and activation rate decrease as excitability increases in stretch cases but not in electrically enhanced cases. These results collectively demonstrate that a small stretch in physiological range can modulate neural activities significantly, suggesting that mechanical events can be employed as a novel tool for the modulation of neural plasticity. PMID:26300729

  13. Stretch due to Penile Prosthesis Reservoir Migration

    PubMed Central

    Baten, E.; Vandewalle, T.; van Renterghem, K.

    2016-01-01

    A 43-year old patient presented to the emergency department with stretch, due to impossible deflation of the penile prosthesis, 4 years after successful implant. A CT-scan showed migration of the reservoir to the left rectus abdominis muscle. Refilling of the reservoir was inhibited by muscular compression, causing stretch. Removal and replacement of the reservoir was performed, after which the prosthesis was well-functioning again. Migration of the penile prosthesis reservoir is extremely rare but can cause several complications, such as stretch. PMID:26793592

  14. Role of fluid density in shaping eruption currents driven by frontal particle blow-out

    NASA Astrophysics Data System (ADS)

    Carroll, C. S.; Turnbull, B.; Louge, M. Y.

    2012-06-01

    We study the role of suspension density in eruption currents, a regime of gravity-driven flow that is sustained by massive, localized blow-out of particles acting as a steady source of heavier fluid injected into a uniform flow at high Reynolds number. Inspired by the potential flow solution of Saffman and Yuen ["Finite-amplitude interfacial waves in the presence of a current," J. Fluid Mech. 123, 459-476 (1982), 10.1017/S0022112082003152], we show that the relative density difference between the two fluids swells the size of the current's head without changing its shape, while inducing a velocity jump at the interface. We test this inviscid theory against inviscid and large-eddy-simulations. We also conduct experiments in a water flume, where a line source of fluorescent brines of various densities is injected in a cross-stream and visualized with a narrow sheet of light. Simulations and experiments reveal that, with isotropic velocity distribution on a finite source, eruption currents expand further and develop interface oscillations, but the inviscid theory still captures relative swelling induced by density. We compare predictions to the static pressure data of McElwaine and Turnbull ["Air pressure data from the Vallee de la Sionne avalanches of 2004," J. Geophys. Res. 110, F03010, doi:, 10.1029/2004JF000237 (2005)] in powder snow avalanches.

  15. Springback prediction and optimization of variable stretch force trajectory in three-dimensional stretch bending process

    NASA Astrophysics Data System (ADS)

    Teng, Fei; Zhang, Wanxi; Liang, Jicai; Gao, Song

    2015-11-01

    Most of the existing studies use constant force to reduce springback while researching stretch force. However, variable stretch force can reduce springback more efficiently. The current research on springback prediction in stretch bending forming mainly focuses on artificial neural networks combined with the finite element simulation. There is a lack of springback prediction by support vector regression (SVR). In this paper, SVR is applied to predict springback in the three-dimensional stretch bending forming process, and variable stretch force trajectory is optimized. Six parameters of variable stretch force trajectory are chosen as the input parameters of the SVR model. Sixty experiments generated by design of experiments (DOE) are carried out to train and test the SVR model. The experimental results confirm that the accuracy of the SVR model is higher than that of artificial neural networks. Based on this model, an optimization algorithm of variable stretch force trajectory using particle swarm optimization (PSO) is proposed. The springback amount is used as the objective function. Changes of local thickness are applied as the criterion of forming constraints. The objection and constraints are formulated by response surface models. The precision of response surface models is examined. Six different stretch force trajectories are employed to certify springback reduction in the optimum stretch force trajectory, which can efficiently reduce springback. This research proposes a new method of springback prediction using SVR and optimizes variable stretch force trajectory to reduce springback.

  16. Effect of modified hold-relax stretching and static stretching on hamstring muscle flexibility

    PubMed Central

    Ahmed, Hashim; Iqbal, Amir; Anwer, Shahnawaz; Alghadir, Ahmad

    2015-01-01

    [Purpose] The aim of present study was to compare the effectiveness of modified hold-relax stretching and static stretching in improving the hamstring muscle flexibility. [Subjects and Methods] Forty-five male subjects with hamstring tightness were included in this study. The subjects were randomly placed into three groups: the modified hold-relax stretching, static stretching and control groups. The modified hold-relax stretching group performed 7 seconds of isometric contraction and then relaxed for 5 seconds, and this was repeated five times daily for five consecutive days. The static stretching group received 10 minutes of static stretching with the help of a pulley and weight system for five consecutive days. The control group received only moist heat for 20 minutes for five consecutive days. A baseline reading of passive knee extension (PKE) was taken prior to the intervention; rest measurements were taken immediate post intervention on day 1, day 3, day 5, and after a 1 week follow-up, i.e., at the 12th day. [Results] On comparing the baseline readings of passive knee extension (PKE), there was no difference noted between the three groups. On comparing the posttest readings on day 5 between the 3 groups, a significant difference was noted. However, post hoc analysis revealed an insignificant difference between the modified hold-relax stretching and static stretching groups. There was a significant difference between the static stretching and control groups and between the modified hold-relax stretching and control groups. [Conclusion] The results of this study indicate that both the modified hold-relax stretching technique and static stretching are equally effective, as there was no significant difference in improving the hamstring muscle flexibility between the two groups. PMID:25729210

  17. MHD boundary layer flow of Casson fluid passing through an exponentially stretching permeable surface with thermal radiation

    NASA Astrophysics Data System (ADS)

    Swati, Mukhopadhyay; Iswar, Chandra Moindal; Tasawar, Hayat

    2014-10-01

    This article numerically examines the boundary layer flow due to an exponentially stretching surface in the presence of an applied magnetic field. Casson fluid model is used to characterize the non-Newtonian fluid behavior. The flow is subjected to suction/blowing at the surface. Analysis is carried out in presence of thermal radiation and prescribed surface heat flux. In this study, an exponential order stretching velocity and prescribed exponential order surface heat flux are accorded with each other. The governing partial differential equations are first converted into nonlinear ordinary differential equations by using appropriate transformations and then solved numerically. The effect of increasing values of the Casson parameter is to suppress the velocity field. However the temperature is enhanced when Casson parameter increases. It is found that the skin-friction coefficient increases with increasing values of suction parameter. Temperature also increases for large values of power index n in both suction and blowing cases at the boundary. It is observed that the thermal radiation enhances the effective thermal diffusivity and hence the temperature rises.

  18. Golimumab Injection

    MedlinePlus

    ... at golimumab injection before injecting it. Check the expiration date printed on the auto-injection device or carton and do not use the medication if the expiration date has passed. Do not use a prefilled syringe ...

  19. Stretch reflex oscillations and essential tremor.

    PubMed Central

    Elble, R J; Higgins, C; Moody, C J

    1987-01-01

    Using a computer-controlled torque motor and manipulandum, 50 ms torque pulses and 70 second trains of binary pseudorandom torque disturbances were applied to the wrists of 10 adult controls and 22 patients with essential tremor in order to study the interaction between mechanically-induced stretch-reflex oscillations and essential tremor. These two oscillations were separated by applying inertial and spring loads to the wrist. There was no evidence of increased or unstable stretch-reflex activity in the essential tremor patients, and stretch-reflex latencies did not correlate with the frequency of essential tremor. Essential tremor and mechanically-induced stretch-reflex oscillations are separate phenomena capable of complex interaction. PMID:3612149

  20. Investing in a Large Stretch Press

    NASA Technical Reports Server (NTRS)

    Choate, M.; Nealson, W.; Jay, G.; Buss, W.

    1986-01-01

    Press for forming large aluminum parts from plates provides substantial economies. Study assessed advantages and disadvantages of investing in large stretch-forming press, and also developed procurement specification for press.

  1. Blow-up properties in the parabolic problems with anisotropic nonstandard growth conditions

    NASA Astrophysics Data System (ADS)

    Liu, Bingchen; Yang, Jie

    2016-03-01

    In this paper, we study the parabolic problems with anisotropic nonstandard growth nonlinearities. We first give the existence and uniqueness of weak solutions in variable Sobolev spaces. Second, we use the energy methods to show the existence of blow-up solutions with negative or positive initial energy, respectively. Both the variable exponents and the coefficients make important roles in Fujita blow-up phenomena. Moreover, asymptotic properties of the blow-up solutions are determined.

  2. The development of three-dimensional adjoint method for flow control with blowing in convergent-divergent nozzle flows

    NASA Astrophysics Data System (ADS)

    Sikarwar, Nidhi

    The noise produced by the low bypass ratio turbofan engines used to power fighter aircraft is a problem for communities near military bases and for personnel working in close proximity to the aircraft. For example, carrier deck personnel are subject to noise exposure that can result in Noise-Induced Hearing Loss which in-turn results in over a billion dollars of disability payments by the Veterans Administration. Several methods have been proposed to reduce the jet noise at the source. These methods include microjet injection of air or water downstream of the jet exit, chevrons, and corrugated nozzle inserts. The last method involves the insertion of corrugated seals into the diverging section of a military-style convergent-divergent jet nozzle (to replace the existing seals). This has been shown to reduce both the broadband shock-associated noise as well as the mixing noise in the peak noise radiation direction. However, the original inserts were designed to be effective for a take-off condition where the jet is over-expanded. The nozzle performance would be expected to degrade at other conditions, such as in cruise at altitude. A new method has been proposed to achieve the same effects as corrugated seals, but using fluidic inserts. This involves injection of air, at relatively low pressures and total mass flow rates, into the diverging section of the nozzle. These fluidic inserts" deflect the flow in the same way as the mechanical inserts. The fluidic inserts represent an active control method, since the injectors can be modified or turned off depending on the jet operating conditions. Noise reductions in the peak noise direction of 5 to 6 dB have been achieved and broadband shock-associated noise is effectively suppressed. There are multiple parameters to be considered in the design of the fluidic inserts. This includes the number and location of the injectors and the pressures and mass flow rates to be used. These could be optimized on an ad hoc basis with

  3. Modeling of Droplet Generation in a Top Blowing Steelmaking Process

    NASA Astrophysics Data System (ADS)

    Rout, Bapin Kumar; Brooks, Geoff; Subagyo; Rhamdhani, M. Akbar; Li, Zushu

    2016-08-01

    Quantification of metal droplets ejected due to impinging gas jet on the surface of liquid metal is an important parameter for the understanding and for the modeling of the refining kinetics of reactions in slag-metal emulsion zone. In the present work, a numerical study has been carried out to critically examine the applicability of droplet generation rate correlation previously proposed by Subagyo et al. on the basis of dimensionless blowing number (N B). The blowing number was re-evaluated at the impingement point of jet with taking into account the temperature effect of change in density and velocity of the gas jet. The result obtained from the work shows that the modified blowing number N B,T at the furnace temperature of 1873 K (1600 °C) is approximately double in magnitude compared to N B calculated by Subagyo and co-workers. When N B,T has been employed to the Subagyo's empirical correlation for droplet generation, a wide mismatch is observed between the experimental data obtained from cold model and hot model experiments. The reason for this large deviation has been investigated in the current study, and a theoretical approach to estimate the droplet generation rate has been proposed. The suitability of the proposed model has been tested by numerically calculating the amount of metals in slag. The study shows that the weight of metals in emulsion falls in the range of 0 to 21 wt pct of hot metal weight when droplet generation rate has been calculated at ambient furnace temperature of 1873 K (1600 °C).

  4. Controlled vortical flow on delta wings through unsteady leading edge blowing

    NASA Technical Reports Server (NTRS)

    Lee, K. T.; Roberts, Leonard

    1990-01-01

    The vortical flow over a delta wing contributes an important part of the lift - the so called nonlinear lift. Controlling this vortical flow with its favorable influence would enhance aircraft maneuverability at high angle of attack. Several previous studies have shown that control of the vortical flow field is possible through the use of blowing jets. The present experimental research studies vortical flow control by applying a new blowing scheme to the rounded leading edge of a delta wing; this blowing scheme is called Tangential Leading Edge Blowing (TLEB). Vortical flow response both to steady blowing and to unsteady blowing is investigated. It is found that TLEB can redevelop stable, strong vortices even in the post-stall angle of attack regime. Analysis of the steady data shows that the effect of leading edge blowing can be interpreted as an effective change in angle of attack. The examination of the fundamental time scales for vortical flow re-organization after the application of blowing for different initial states of the flow field is studied. Different time scales for flow re-organization are shown to depend upon the effective angle of attack. A faster response time can be achieved at angles of attack beyond stall by a suitable choice of the initial blowing momentum strength. Consequently, TLEB shows the potential of controlling the vortical flow over a wide range of angles of attack; i.e., in both for pre-stall and post-stall conditions.

  5. A One-Dimensional Global-Scaling Erosive Burning Model Informed by Blowing Wall Turbulence

    NASA Technical Reports Server (NTRS)

    Kibbey, Timothy P.

    2014-01-01

    A derivation of turbulent flow parameters, combined with data from erosive burning test motors and blowing wall tests results in erosive burning model candidates useful in one-dimensional internal ballistics analysis capable of scaling across wide ranges of motor size. The real-time burn rate data comes from three test campaigns of subscale segmented solid rocket motors tested at two facilities. The flow theory admits the important effect of the blowing wall on the turbulent friction coefficient by using blowing wall data to determine the blowing wall friction coefficient. The erosive burning behavior of full-scale motors is now predicted more closely than with other recent models.

  6. Laminar free convection from a sphere with blowing and suction

    SciTech Connect

    Huang, Mingjer; Chen, Gahokuang )

    1987-05-01

    The effect of mass transfer on free convection from a vertical plate has been studied by Eichhorn (1960), Sparrow and Cess (1961), Merkin (1972), and Parikh (1974). Recently, Merkin (1975) gave an asymptotic series solution for two-dimensional bodies. Minkowycz and Sparrow (1979) studied a vertical cylinder in a natural convective flow. According to their conclusions, the heat transfer rate increases with suction and decreases with blowing. The present note is concerned with the study of the influence of Prandtl number and surface mass transfer on a steady, laminar, free convective flow over a sphere with nonuniform surface temperature or heat flux.

  7. Ground effects on USB configurations. [Upper Surface Blowing

    NASA Technical Reports Server (NTRS)

    Lan, C. E.

    1979-01-01

    Recent investigations of ground effects on aerodynamic characteristics have been stimulated by the interest in powered-lift STOL airplanes. The ground effects on upper-surface-blowing (USB) configurations may involve change in both the circulation forces and the jet reaction forces. In this note, a theoretical method is proposed for predicting these effects. It is shown that the predicted results agree well with available experimental data. In particular, the wing-alone method is shown to be incapable of predicting the ground effects of USB configurations.

  8. Two blowing concepts for roll and lateral control of aircraft

    NASA Technical Reports Server (NTRS)

    Tavella, D. A.; Wood, N. J.; Lee, C. S.; Roberts, L.

    1986-01-01

    Two schemes to modulate aerodynamic forces for roll and lateral control of aircraft have been investigated. The first scheme, called the lateral blowing concept, consists of thin jets of air exiting spanwise, or at small angle with the spanwise direction, from slots at the tips of straight wings. For this scheme, in addition to experimental measurements, a theory was developed showing the analytical relationship between aerodynamic forces and jet and wing parameters. Experimental results confirmed the theoretically derived scaling laws. The second scheme, which was studied experimentally, is called the jet spoiler concept and consists of thin jets exiting normally to the wing surface from slots aligned with the spanwise direction.

  9. NSF FY 1987 budget dealt blow in Congress

    NASA Astrophysics Data System (ADS)

    Katzoff, Judith A.

    Although it passed through the congressional authorization process unscathed, the budget request for the National Science Foundation (NSF) for fiscal year (FY) 1987 was dealt a serious blow on July 23, 1986, when a House appropriations subcommittee recommended that nearly $146 million be cut from the agency's request for “research and related activities” (R&RA). The full House Appropriations Committee went on to endorse this recommendation on July 31.The committee report accompanying the House appropriation bill leaves the distribution of cuts within R&RA up to the discretion of the NSF director. The report does, however, protect the budget request for the ocean drilling program from a cut.

  10. Using Visual Range Data For Highway Operations In Blowing Snow

    NASA Astrophysics Data System (ADS)

    Tabler, Ronald D.

    1983-09-01

    This paper describes characteristics of visual range attenuation in blowing snow in rela-tion to motorist vision. Visual range V is related to wind speed U according to V = A U-5 with the A coefficient changing in response to snow availability. A lower limit for visual range is described with A = 1.1.108 m6.s-5 An operational monitoring system used on Interstate Highway 80 in Wyoming demonstrates how real-time computer analysis of photometric data can be used to determine the A value, interpret visual range in terms of vehicle operation, and provide automated traffic operations decisions.

  11. Implementation of a Blowing Boundary Condition in the LAURA Code

    NASA Technical Reports Server (NTRS)

    Thompson, Richard a.; Gnoffo, Peter A.

    2008-01-01

    Preliminary steps toward modeling a coupled ablation problem using a finite-volume Navier-Stokes code (LAURA) are presented in this paper. Implementation of a surface boundary condition with mass transfer (blowing) is described followed by verification and validation through comparisons with analytic results and experimental data. Application of the code to a carbon-nosetip ablation problem is demonstrated and the results are compared with previously published data. It is concluded that the code and coupled procedure are suitable to support further ablation analyses and studies.

  12. [Sciatica. From stretch rack to microdiscectomy].

    PubMed

    Gruber, P; Böni, T

    2015-12-01

    In ancient times as well as in the Middle Ages treatment options for discogenic nerve compression syndrome were limited and usually not very specific because of low anatomical and pathophysiological knowledge. The stretch rack (scamnum Hippocratis) was particularly prominent but was widely used as a therapeutic device for very different spinal disorders. Since the beginning of the nineteenth century anatomical knowledge increased and the advances in the fields of asepsis, anesthesia and surgery resulted in an increase in surgical interventions on the spine. In 1908 the first successful lumbar discectomy was initiated and performed by the German neurologist Heinrich O. Oppenheim (1858-1919) and the surgeon Fedor Krause (1857-1937); however, neither recognized the true pathological condition of discogenic nerve compression syndrome. With the landmark report in the New England Journal of Medicine in 1934, the two American surgeons William Jason Mixter (1880-1958) and Joseph Seaton Barr (1901-1963) finally clarified the pathomechanism of lumbar disc herniation and furthermore, propagated discectomy as the standard therapy. Since then interventions on intervertebral discs rapidly increased and the treatment options for lumbar disc surgery quickly evolved. The surgical procedures changed over time and were continuously being refined. In the late 1960s the surgical microscope was introduced for spinal surgery by the work of the famous neurosurgeon Mahmut Gazi Yasargil and his colleague Wolfhard Caspar and so-called microdiscectomy was introduced. Besides open discectomy other interventional techniques were developed to overcome the side effects of surgical procedures. In 1964 the American orthopedic surgeon Lyman Smith (1912-1991) introduced chemonucleolysis, a minimally invasive technique consisting only of a cannula and the proteolytic enzyme chymopapain, which is injected into the disc compartment to dissolve the displaced disc material. In 1975 the Japanese orthopedic

  13. Design of a new membrane stretching device

    NASA Astrophysics Data System (ADS)

    Shao, Yiran

    Cell stretching device has been applied into the lab use for many years to help researchers study about the behavior of cells during the stretching process. Because the cell responses to the different mechanical stimuli, especially in the case of disease, the cell stretching device is a necessary tool to study the cell behavior in a controlled environment. However existing devices have limitations, such as too big to fit the culture chamber, unable to be observed during the stretching process and too expensive to fabricate. In this thesis, a new cell stretcher is designed to resolve these limitations. Many typical cell stretching devices only work under simple conditions. For instance they can only apply the strain on the cell in uniaxial or equibiaxial directions. On the other hand the environment of cells' survival is varying. Many new cell stretchers have been developed, which have the same property that cells can be stretched via the radical deformation of the elastomeric membrane. The aim of this new design is to create a cell stretching device that fits in general lab conditions. This device is designed to fit on a microscope to observe, as well as in the incubator. In addition, two small step motors are used to control the strain, adjust the frequency, and maintain the stability precisely. Problems such as the culture media leakage and the membrane breakage are solved by the usage of multiple materials for both the cell stretcher and the membrane. Based on the experimental results, this device can satisfy the requirements of target users with a reduced manufacturing cost. In the future, an auto-focus tracking function will be developed to allow real time observation of the cells' behavior.

  14. Adaptive Suction and Blowing for Twin-Tail Buffet Control

    NASA Technical Reports Server (NTRS)

    Kandil, Osama A.; Yang, Zhi

    1999-01-01

    Adaptive active flow control for twin-tail buffet alleviation is investigated. The concept behind this technique is to place control ports on the tail outer and inner surfaces with flow suction or blowing applied through these ports in order to minimize the pressure difference across the tail. The suction or blowing volume flow rate from each port is proportional to the pressure difference across the tail at this location. A parametric study of the effects of the number and location of these ports on the buffet response is carried out. The computational model consists of a sharp-edged delta wing of aspect ratio one and swept-back flexible twin tail with taper ratio of 0.23. This complex multidisciplinary problem is solved sequentially using three sets of equations for the fluid flow, aeroelastic response and grid deformation, using a dynamic multi-block grid structure. The computational model is pitched at 30 deg angle of attack. The freestream Mach number and Reynolds number are 0.3 and 1.25 million, respectively. The model is investigated for the inboard position of the twin tails, which corresponds to a separation distance between the twin tails of 33% of the wing span. Comparison of the time history and power spectral density responses of the tails for various distributions of the control ports are presented and discussed.

  15. Coupling dynamic blow down and pool evaporation model for LNG.

    PubMed

    Woodward, John L

    2007-02-20

    Treating the dynamic effects of accidental discharges of liquefied natural gas (LNG) is important for realistic predictions of pool radius. Two phenomena have important influence on pool spread dynamics, time-varying discharge (blow down) and pool ignition. Time-varying discharge occurs because a punctured LNG tanker or storage tank drains with a decreasing liquid head and decreasing head-space pressure. Pool ignition increases the evaporation rate of a pool and consequently decreases the ultimate pool area. This paper describes an approach to treat these phenomena in a dynamic pool evaporation model. The pool evaporation model developed here has two separate regimes. Early in the spill, momentum forces dominate and the pool spreads independently of pool evaporation rate and the corresponding heat transfer rate. After the average pool depth drops below a minimum value, momentum forces are largely dissipated and the thin edges of the pool completely evaporate, so pool area is established by the heat transfer rate. The maximum extent of a burning pool is predicted to be significantly less than that of an unignited pool because the duration of the first regime is reduced by higher heat transfer rates. The maximum extent of an LNG pool is predicted to be larger upon accounting for blow down compared with using a constant average discharge rate. However, the maximum pool extent occurs only momentarily before retreating. PMID:17184912

  16. Gas Blowing: Mass Transfer in Gas and Melt

    NASA Astrophysics Data System (ADS)

    Sortland, Øyvind Sunde; Tangstad, Merete

    2014-09-01

    Metallurgical routes for solar grade silicon production are being developed as alternatives to chemical processes for their potential to achieve cost reductions, increased production volume, and reduced environmental and safety concerns. An important challenge in the development of metallurgical routes relates to the higher impurity concentrations in the silicon product, particularly for boron and other elements that are not efficiently segregated in solidification techniques. The reactive gas refining process is studied for its potential to remove boron below the solar grade silicon target concentration in a single step by blowing steam and hydrogen gas jets onto the melt surface. Boron in a silicon melt is extracted to HBO gas in parallel to active oxidation of silicon. The literature is not unified regarding the rate determining step in this process. Relevant theories and equations for gas blowing in induction furnaces are combined and used to explain mass transfer in experiments. Mass transfer in the melt and gas is investigated by comparing resistance and induction heating of the melt, and varying gas flow rate, crucible diameter, diameter of the gas lance, and the position of the gas lance above the melt surface. The rate of boron removal is found to increase with increasing gas flow rate and crucible diameter. A relatively high fraction of the reactive gas is utilized in the process, and supply of steam in the bulk gas is the only identified rate determining step.

  17. Optimal determination of soot-blowing and condenser cleaning schedule

    SciTech Connect

    Alag, S.; Chatterjee, J.; Jeyarasasingam, K.; Jain, P.

    1998-07-01

    The authors describe an approach for determining the optimal schedule for soot-blowing and condenser cleaning in a power plant. The soot blower optimizer minimizes a configurable optimization function consisting of loss due to degraded operation, increased emissions, and permanent damage to the component. It used deposition factor, an integral term that is dependent on the history of the plant operation since the last soot blowing and is a non-linear function of parameters that lead to an accumulation of soot on the component. The condenser cleaning optimization process is formulated into a dynamic programming formulation where a decision is made between carrying out a short, long, or no cleaning. Their implementation has several advantages over previous approaches, due to access to an enhanced plant model that enables one to carry out detailed what-if analysis, estimation of missing measurements, availability of a plant equipment performance diagnosis system, the use of emissions in analysis, analysis of all plant components in unison, and access to plant operation history.

  18. Numerical Analysis of Film Cooling at High Blowing Ratio

    NASA Technical Reports Server (NTRS)

    El-Gabry, Lamyaa; Heidmann, James; Ameri, Ali

    2009-01-01

    Computational Fluid Dynamics is used in the analysis of a film cooling jet in crossflow. Predictions of film effectiveness are compared with experimental results for a circular jet at blowing ratios ranging from 0.5 to 2.0. Film effectiveness is a surface quantity which alone is insufficient in understanding the source and finding a remedy for shortcomings of the numerical model. Therefore, in addition, comparisons are made to flow field measurements of temperature along the jet centerline. These comparisons show that the CFD model is accurately predicting the extent and trajectory of the film cooling jet; however, there is a lack of agreement in the near-wall region downstream of the film hole. The effects of main stream turbulence conditions, boundary layer thickness, turbulence modeling, and numerical artificial dissipation are evaluated and found to have an insufficient impact in the wake region of separated films (i.e. cannot account for the discrepancy between measured and predicted centerline fluid temperatures). Analyses of low and moderate blowing ratio cases are carried out and results are in good agreement with data.

  19. What Protects Certain Nerves from Stretch Injury?

    PubMed

    Schraut, Nicholas B; Walton, Sharon; Bou Monsef, Jad; Shott, Susan; Serici, Anthony; Soulii, Lioubov; Amirouche, Farid; Gonzalez, Mark H; Kerns, James M

    2016-01-01

    The human tibial nerves is less prone to injury following joint arthroplasty compared with the peroneal nerves. Besides the anatomical distribution, other features may confer protection from stretch injury. We therefore examined the size, shape and connective tissue distribution for the two nerves. The tibial and peroneal nerves from each side of nine fresh human cadavers we reharvested mid-thigh. Proximal segments manually stretched 20%-25% were fixed in aldehyde, while the adjacent distal segments were fixed in their natural length. Paraffin sections stained by Masson's trichrome method for connective tissue were examined by light microscopy. Tibial nerves had 2X more fascicles compared with the peroneal, but the axonal content appeared similar. Analysis showed that neither nerve had a significant reduction in cross sectional area of the fascicles following stretch. However, fascicles from stretched tibial nerves become significantly more oval compared with those from unstretched controls and peroneal nerves. Tibial nerves had a greater proportion that was extrafascicular tissue (50-55%) compared with peroneal nerves (38%-42%). This epineurium was typically adipose tissue. Perineurial thickness in both nerves was directly related to fascicular size. Tibial nerves have several unique histological features associated with size, shape and tissue composition compared with the peroneal nerve. We suggest that more fascicles with their tightly bound perineurium and more robust epineurium afford protection against stretch injury. Mechanical studies should clarify how size and shape contribute to nerve protection and/or neurapraxia. PMID:26529568

  20. Characterization of impurity confinement on Alcator C-Mod using a multi-pulse laser blow-off system.

    PubMed

    Howard, N T; Greenwald, M; Rice, J E

    2011-03-01

    A new laser blow-off system for use in impurity transport studies on Alcator C-Mod was developed and installed for the 2009 run campaign. Its design included capabilities for multiple impurity injections during a single plasma pulse and remote manipulation of the ablated spot size. The system uses a 0.68 J, Nd:YAG laser operating at up to 10 Hz coupled with the fast beam steering via a 2D piezoelectric mirror mount able to move spot locations in the 100 ms between laser pulses and a remote controllable optical train that allow ablated spot sizes to vary from ∼0.5 to 7 mm. The ability to ablate a wide range in target Z along with Alcator C-Mod's extensive diagnostic capabilities (soft x-ray, vacuum ultraviolet (VUV), charge exchange spectroscopy, etc.) allows for detailed studies of the impurity transport dependencies and mechanisms. This system has demonstrated the achievement of all its design goals including the ability for non-perturbative operation allowing for insight into underlying impurity transport processes. A detailed overview of the laser blow-off system and initial results of operation are presented. This includes an investigation into the characterization of impurity confinement in the I-mode confinement regime recently investigated on C-Mod. PMID:21456742

  1. Characterization of impurity confinement on Alcator C-Mod using a multi-pulse laser blow-off system

    SciTech Connect

    Howard, N. T.; Greenwald, M.; Rice, J. E.

    2011-03-15

    A new laser blow-off system for use in impurity transport studies on Alcator C-Mod was developed and installed for the 2009 run campaign. Its design included capabilities for multiple impurity injections during a single plasma pulse and remote manipulation of the ablated spot size. The system uses a 0.68 J, Nd:YAG laser operating at up to 10 Hz coupled with the fast beam steering via a 2D piezoelectric mirror mount able to move spot locations in the 100 ms between laser pulses and a remote controllable optical train that allow ablated spot sizes to vary from {approx}0.5 to 7 mm. The ability to ablate a wide range in target Z along with Alcator C-Mod's extensive diagnostic capabilities (soft x-ray, vacuum ultraviolet (VUV), charge exchange spectroscopy, etc.) allows for detailed studies of the impurity transport dependencies and mechanisms. This system has demonstrated the achievement of all its design goals including the ability for non-perturbative operation allowing for insight into underlying impurity transport processes. A detailed overview of the laser blow-off system and initial results of operation are presented. This includes an investigation into the characterization of impurity confinement in the I-mode confinement regime recently investigated on C-Mod.

  2. Ratio of nose blow results to intakes during the decommissioning of a facility at Dounreay.

    PubMed

    Spencer, David; Bull, Richard K; White, Simon

    2007-01-01

    During the decommissioning of a large glove box facility at Dounreay, in addition to engineering and administration controls, workers wore pressurised suits to minimise their intake of radionuclides. The workers provided nose blows after each suited operation to provide an indication of the effectiveness of protective measures. The nose blows were also used as indicators of radiological significant intakes. This paper examines the distribution of ratios of nose blow to assessed intake. A geometric mean and variance of the ratio of nose blows to intakes have been derived. The nose blows were provided over a period of 2 y and the alpha-emitting nuclides present are 239Pu, 241Am and 238Pu. Twenty-two nose blow results each with follow-up urine and faecal results are included in the study. The effectiveness of nose blows as an indicator of radiological conditions and as a trigger for the investigation of significant doses is considered. The ratio between assessed intake and nose blow result was shown to be very large. PMID:18223182

  3. Awareness and Ethical Orientation of Alternatively Certified Prospective Teachers to Intention for Whistle Blowing

    ERIC Educational Resources Information Center

    Toker Gokce, Asiye

    2013-01-01

    This study inquires whistle blowing intentions of alternatively certified prospective teachers, investigating their moral reasoning to blow the whistle. Specifically three hypotheses were tested: Overall ethical awareness of the alternatively certified prospective teachers is high; the participants will identify reasons related to philosophical…

  4. Stokes' problem with cross-flow-simple example of transient boundary-layer blow-off

    NASA Astrophysics Data System (ADS)

    Lu, P.-C.

    Some fundamental understanding of the blow-off (i.e., the disappearance of wall shear) of a transient, laminar boundary layer by a strong cross-flow is gained by extending the classical Stokes' first problem to include blowing (and suction). It is found, by asymptotic studies as well as detailed numerical display of exact solutions for a variety of situations (including a similarity solution where the cross-flow varies inversely with the square root of time) that there are, in general, three stages clearly discernible when blowing is present: (1) pre-blow-off stage during which the influence of the cross-flow has not shown up yet; (2) blow-off stage during which the boundary layer exhibits a zero slope in its velocity profile, and the blow-off begins; and (3) post-blow-off stage during which a wave front is seen to ride with the cross-flow, carrying with it a rather rapid change of motion of the wall to the rest-state before it, while the blow-off at the wall is sustained. Furthermore, for very large Reynolds numbers, the front in the third stage becomes very sharp, and the accompanying change very sudden. In contrast, in the case of suction, the boundary layer is seen to stick to the wall, in a more exaggerated manner; and the situation approaches a steady limit for large times.

  5. A Study of Pulsed Blowing Effect on Flow Separation over Flap

    NASA Astrophysics Data System (ADS)

    Wang, Yankui; Zhou, Ping; Li, Qian

    2015-11-01

    With the development of the modern aircraft, such as tailless flying configuration, traditional flaps are also the main control surfaces for flight controlling. However, the efficiency of the flap is not only descent quickly due to flow separation over itself under higher deflection angle of flap, but also is evidently influenced by the flow coming down from the upstream wing. A novel flow control technique to improve the flow separation over the flap by pulsed blowing is investigated in this paper by wind tunnel test under Reynolds number of 0.6* 10E6 2.4* 10E6. To begin with, the control performance for flow separation over the flap is very sensitive to the blowing position and direction and the flow separation can be recovered by the pulsed blowing evidently. Secondly, the pulsed blowing efficiency is 30% higher than that of continuous blowing with the same consumption. In addition, the pulsed blowing efficiency increases quickly with the increasing of pulsed blowing frequency and keep constant gradually when the pulsed blowing Stroul number is bigger than 0.6. National Natural Science Foundation of China (11272035).

  6. Shooting method for solution of boundary-layer flows with massive blowing

    NASA Technical Reports Server (NTRS)

    Liu, T.-M.; Nachtsheim, P. R.

    1973-01-01

    A modified, bidirectional shooting method is presented for solving boundary-layer equations under conditions of massive blowing. Unlike the conventional shooting method, which is unstable when the blowing rate increases, the proposed method avoids the unstable direction and is capable of solving complex boundary-layer problems involving mass and energy balance on the surface.

  7. Effect of mechanical stretching on DNA conductance.

    PubMed

    Bruot, Christopher; Xiang, Limin; Palma, Julio L; Tao, Nongjian

    2015-01-27

    Studying the structural and charge transport properties in DNA is important for unraveling molecular scale processes and developing device applications of DNA molecules. Here we study the effect of mechanical stretching-induced structural changes on charge transport in single DNA molecules. The charge transport follows the hopping mechanism for DNA molecules with lengths varying from 6 to 26 base pairs, but the conductance is highly sensitive to mechanical stretching, showing an abrupt decrease at surprisingly short stretching distances and weak dependence on DNA length. We attribute this force-induced conductance decrease to the breaking of hydrogen bonds in the base pairs at the end of the sequence and describe the data with a mechanical model. PMID:25530305

  8. Stretching and folding in finite time.

    PubMed

    Ma, Tian; Ouellette, Nicholas T; Bollt, Erik M

    2016-02-01

    Complex flows mix efficiently, and this process can be understood by considering the stretching and folding of material volumes. Although many metrics have been devised to characterize stretching, fewer are able to capture folding in a quantitative way in spatiotemporally variable flows. Here, we extend our previous methods based on the finite-time curving of fluid-element trajectories to nonzero scales and show that this finite-scale finite-time curvature contains information about both stretching and folding. We compare this metric to the more commonly used finite-time Lyapunov exponent and illustrate our methods using experimental flow-field data from a quasi-two-dimensional laboratory flow. Our new analysis tools add to the growing set of Lagrangian methods for characterizing mixing in complex, aperiodic fluid flows. PMID:26931593

  9. Stretching and folding in finite time

    NASA Astrophysics Data System (ADS)

    Ma, Tian; Ouellette, Nicholas T.; Bollt, Erik M.

    2016-02-01

    Complex flows mix efficiently, and this process can be understood by considering the stretching and folding of material volumes. Although many metrics have been devised to characterize stretching, fewer are able to capture folding in a quantitative way in spatiotemporally variable flows. Here, we extend our previous methods based on the finite-time curving of fluid-element trajectories to nonzero scales and show that this finite-scale finite-time curvature contains information about both stretching and folding. We compare this metric to the more commonly used finite-time Lyapunov exponent and illustrate our methods using experimental flow-field data from a quasi-two-dimensional laboratory flow. Our new analysis tools add to the growing set of Lagrangian methods for characterizing mixing in complex, aperiodic fluid flows.

  10. Stretched arc discharge in produced water.

    PubMed

    Cho, Y I; Wright, K C; Kim, H S; Cho, D J; Rabinovich, A; Fridman, A

    2015-01-01

    The objective of the present study was to investigate the feasibility of stretching an arc discharge in produced water to increase the volume of produced water treated by plasma. Produced water is the wastewater generated by hydraulic fracturing of shale during the production phase in shale-oil or shale-gas exploration. The electric conductivity of produced water is in the range of 50-200 mS/cm, which provides both a challenge and opportunity for the application of plasmas. Stretching of an arc discharge in produced water was accomplished using a ground electrode and two high-voltage electrodes: one positioned close to the ground electrode and the other positioned farther away from the ground. The benefit of stretching the arc is that the contact between the arc and water is significantly increased, resulting in more efficient plasma treatment in both performance and energy cost. PMID:25638080

  11. System performance analysis of stretched membrane heliostats

    SciTech Connect

    Anderson, J V; Murphy, L M; Short, W; Wendelin, T

    1985-12-01

    The optical performance of both focused and unfocused stretched membrane heliostats was examined in the context of the overall cost and performance of central receiver systems. The sensitivity of optical performance to variations in design parameters such as the system size (capacity), delivery temperature, heliostat size, and heliostat surface quality was also examined. The results support the conclusion that focused stretched membrane systems provide an economically attractive alternative to current glass/metal heliostats over essentially the entire range of design parameters studied. In addition, unfocused stretched membrane heliostats may be attractive for a somewhat more limited range of applications, which would include the larger plant sizes (e.g., 450 MW) and lower delivery temperatures (e.g., 450/sup 0/C), or situations in which the heliostat size could economically be reduced.

  12. Live Cell Imaging during Mechanical Stretch

    PubMed Central

    Rápalo, Gabriel; Herwig, Josh D.; Hewitt, Robert; Wilhelm, Kristina R.; Waters, Christopher M.; Roan, Esra

    2015-01-01

    There is currently a significant interest in understanding how cells and tissues respond to mechanical stimuli, but current approaches are limited in their capability for measuring responses in real time in live cells or viable tissue. A protocol was developed with the use of a cell actuator to distend live cells grown on or tissues attached to an elastic substrate while imaging with confocal and atomic force microscopy (AFM). Preliminary studies show that tonic stretching of human bronchial epithelial cells caused a significant increase in the production of mitochondrial superoxide. Moreover, using this protocol, alveolar epithelial cells were stretched and imaged, which showed direct damage to the epithelial cells by overdistention simulating one form of lung injury in vitro. A protocol to conduct AFM nano-indentation on stretched cells is also provided. PMID:26325607

  13. All-optical time-stretch digitizer

    NASA Astrophysics Data System (ADS)

    Fard, A. M.; Buckley, B.; Zlatanovic, S.; Brès, C.-S.; Radic, S.; Jalali, B.

    2012-07-01

    We propose and demonstrate an all-optical time-stretch digitizer for real-time capture of ultrafast optical signals, beyond the bandwidths achievable by electronics. This approach uniquely combines four-wave mixing and photonic time-stretch technique to slow down and record high-speed optical signals. As a proof-of-concept, real-time recording of 40-Gb/s non-return-to-zero on-off-keying optical data stream is experimentally demonstrated using a stretch factor of 54 and 1.5-GHz back-end electronic bandwidth. We also report on the observation of dispersion penalty and its mitigation via single-sideband conversion enabled by an optical bandpass filter. Our technique may provide a path to real-time capture of ultrahigh-speed optical data streams.

  14. Anisotropic dewetting on stretched elastomeric substrates.

    PubMed

    Qiao, L; He, L H

    2008-08-01

    We study the instability of a very thin liquid film resting on a uniformly stretched soft elastomeric substrate driven by van der Waals forces. A linear stability analysis shows that the critical fluctuation wavelength in the tensile direction is larger than those in the other directions. The magnitudes of the critical wavelengths are adjustable in the sense that they depend on the principal stretch of the substrate. For example, when the principal stretch of the substrate varies from 1.0 (unstretched) to 3.0, the range of the critical wavelength in the tensile direction increases by 7.0% while that normal to the tensile direction decreases by 8.7%. Therefore, the phenomenon may find potential applications in creating tunable topographically patterned surfaces with nano- to microscale features. PMID:19230211

  15. Stretched arc discharge in produced water

    NASA Astrophysics Data System (ADS)

    Cho, Y. I.; Wright, K. C.; Kim, H. S.; Cho, D. J.; Rabinovich, A.; Fridman, A.

    2015-01-01

    The objective of the present study was to investigate the feasibility of stretching an arc discharge in produced water to increase the volume of produced water treated by plasma. Produced water is the wastewater generated by hydraulic fracturing of shale during the production phase in shale-oil or shale-gas exploration. The electric conductivity of produced water is in the range of 50-200 mS/cm, which provides both a challenge and opportunity for the application of plasmas. Stretching of an arc discharge in produced water was accomplished using a ground electrode and two high-voltage electrodes: one positioned close to the ground electrode and the other positioned farther away from the ground. The benefit of stretching the arc is that the contact between the arc and water is significantly increased, resulting in more efficient plasma treatment in both performance and energy cost.

  16. Optical Data Compression in Time Stretch Imaging

    PubMed Central

    Chen, Claire Lifan; Mahjoubfar, Ata; Jalali, Bahram

    2015-01-01

    Time stretch imaging offers real-time image acquisition at millions of frames per second and subnanosecond shutter speed, and has enabled detection of rare cancer cells in blood with record throughput and specificity. An unintended consequence of high throughput image acquisition is the massive amount of digital data generated by the instrument. Here we report the first experimental demonstration of real-time optical image compression applied to time stretch imaging. By exploiting the sparsity of the image, we reduce the number of samples and the amount of data generated by the time stretch camera in our proof-of-concept experiments by about three times. Optical data compression addresses the big data predicament in such systems. PMID:25906244

  17. Flow visualization studies of blowing from the tip of a swept wing

    NASA Technical Reports Server (NTRS)

    Smith, Jeannette W.; Mineck, Raymond E.; Neuhart, Dan H.

    1990-01-01

    Flow visualization studies of blowing from the tip of a swept wing were conducted in the Langley 16- by 24-inch water tunnel. Four wing tips, each with two independent blowing slots, were tested. The two slots were located one behind the other in the chordwise direction. The wing tips were designed to vary systematically the jet length, the jet in-plane exhaust direction (sweep), and the jet out-of-plane exhaust direction (anhedral). Each blowing slot was tested separately at two angles of attack and at four ratios of jet to free stream velocity ratios. Limited tests were conducted with blowing from both slots simultaneously. Blowing from the tip inhibited inboard spanwise flow on the upper wing surface near the tip. The jet path moved farther away from the tip with increasing jet to free stream velocity ratio and moved closer to the tip with increasing angle of attack.

  18. Analysis of Tangential Slot Blowing on F/A-18 Isolated Forebody

    NASA Technical Reports Server (NTRS)

    Gee, Ken; Rizk, Yehia M.; Schiff, Lewis B.

    1995-01-01

    The generation of significant side forces and yawing moments on an F/A-18 fuselage through tangential slot blowing is analyzed using computational fluid dynamics. The effects of freestream Mach number, jet exit conditions, jet length, and jet location are studied. The effects of over- and underblowing on force and moment production are analyzed. Non-time-accurate solutions are obtained to determine the steady-state side forces, yawing moments, and surface pressure distributions generated by tangential slot blowing. Time-accurate solutions are obtained to study the force onset time lag of tangential slot blowing. Comparison with available experimental data from full-scale wind-tunnel and subscale wind-tunnel tests are made. This computational analysis complements the experimental results and provides a detailed understanding of the effects of tangential slot blowing on the flowfield about the isolated F/A-18 forebody. Additionally, it extends the slot-blowing database to transonic maneuvering Mach numbers.

  19. Tangential blowing for control of strong normal shock - Boundary layer interactions on inlet ramps

    NASA Technical Reports Server (NTRS)

    Schwendemann, M. F.; Sanders, B. W.

    1982-01-01

    The use of tangential blowing from a row of holes in an aft facing step is found to provide good control of the ramp boundary layer, normal shock interaction on a fixed geometry inlet over a wide range of inlet mass flow ratios. Ramp Mach numbers of 1.36 and 1.96 are investigated. The blowing geometry is found to have a significant effect on system performance at the highest Mach number. The use of high-temperature air in the blowing system, however, has only a slight effect on performance. The required blowing rates are significantly high for the most severe test conditions. In addition, the required blowing coefficient is found to be proportional to the normal shock pressure rise.

  20. Whistle-blowing as a form of advocacy: guidelines for the practitioner and organization.

    PubMed

    Greene, Annette D; Latting, Jean Kantambu

    2004-04-01

    Advocacy has been an inherent component of social work since the mid-1800s. The NASW Code of Ethics explicitly promotes advocacy as an ethical stance against inhumane conditions. Whistle-blowing, on the other hand, occurs mostly in the business and public administration disciplines and is relatively unknown in the social work profession. Using facts from composite cases of whistle-blowing incidents, the purpose of this article is to review the social work profession's current stance on advocacy to protect clients' rights, define and describe theoretical and practical knowledge about whistle-blowing based on a literature review, explain whistle-blowing as a special form of advocacy, and offer guidance to potential whistle-blowers and their organizations on how to handle situations in which whistle-blowing is likely to be considered an option. PMID:15124962

  1. A Basic Study on Countermeasure Against Aerodynamic Force Acting on Train Running Inside Tunnel Using Air Blowing

    NASA Astrophysics Data System (ADS)

    Suzuki, Masahiro; Nakade, Koji

    A basic study of flow controls using air blowing was conducted to reduce unsteady aerodynamic force acting on trains running in tunnels. An air blowing device is installed around a model car in a wind tunnel. Steady and periodic blowings are examined utilizing electromagnetic valves. Pressure fluctuations are measured and the aerodynamic force acting on the car is estimated. The results are as follows: a) The air blowing allows reducing the unsteady aerodynamic force. b) It is effective to blow air horizontally at the lower side of the car facing the tunnel wall. c) The reduction rate of the unsteady aerodynamic force relates to the rate of momentum of the blowing to that of the uniform flow. d) The periodic blowing with the same frequency as the unsteady aerodynamic force reduces the aerodynamic force in a manner similar to the steady blowing.

  2. Recent activities on CCMHD power generation studies with Fuji-1 blow-down facility

    SciTech Connect

    Okuno, Y.; Okamura, T.; Yoshikawa, K.

    1995-12-31

    Recent activities on experimental studies with closed cycle MBD {open_quotes}Fuji-1{open_quotes} blow-down facility at Tokyo Institute of Technology are presented. A new disk generator ( Disk-F4 ) has been installed and a new seed injection system has been introduced from IVTAN (Institute of High Temperature in Russia) in 1994.The design concept of the new generator channel is focused mainly on the reliability of high power generation. The Mach number at the generator inlet and the thermal input are increased up to {approximately}2.8 and {approximately}3.0 MW, respectively. In the new seeding system, a melted seed material is pushed by a piston dozator, instead of gas-pressure-driven in the previous system. The controllability of seed fraction is markedly improved, and the large fluctuation as has been observed previously is diminished, although the spatial non-uniformity of seed fraction which could occur in the all previous experiments is observed. In the power generation experiments with the new components, the maximum power output of 502 kW and the enthalpy extraction ratio of 16.7% have been obtained. These values at the present stage are lower than the maximum values previously achieved in the facility. However, the reliable high power generation can be expected for the new generator.

  3. Regulation of skeletal alpha-actin promoter in young chickens during hypertrophy caused by stretch overload.

    PubMed

    Carson, J A; Yan, Z; Booth, F W; Coleman, M E; Schwartz, R J; Stump, C S

    1995-04-01

    Anterior latissimus dorsi (ALD) muscles of 3-wk-old male chickens were injected with plasmids containing various lengths of the chicken skeletal alpha-actin promoter (ranging from -2,090 to -77 relative to the transcription start site) driving luciferase. Hypertrophy of the left ALD muscle was induced by attaching a weight (11% of body wt) to the left wing of each chicken, with the unweighted contralateral wing serving the control. Six days of stretch overload significantly increased muscle mass 110%. Luciferase activity from the -2,090 actin-luciferase chimeric gene increased 127% compared with the contralateral control ALD muscle. Luciferase activities driven by the -424, -202, and -99 actin promoters were 179, 134, and 378% higher, respectively, in the stretched ALD muscle than in the contralateral control ALD muscle. Luciferase activity from the -77 deletion construct was not different between stretched and control muscles. These data indicate that the gene region responding to stretch is downstream of -99 and imply, but do not conclusively prove, that the region between -99 and -77, which contains serum response element 1, contributes to the stretch-induced increase in skeletal alpha-actin promoter activity in the ALD muscle. PMID:7537453

  4. Heat transfer characteristics for the Maxwell fluid flow past an unsteady stretching permeable surface embedded in a porous medium with thermal radiation

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, S.; Ranjan De, P.; Layek, G. C.

    2013-05-01

    An unsteady boundary layer flow of a non-Newtonian fluid over a continuously stretching permeable surface in the presence of thermal radiation is investigated. The Maxwell fluid model is used to characterize the non-Newtonian fluid behavior. Similarity solutions for the transformed governing equations are obtained. The transformed boundary layer equations are then solved numerically by the shooting method. The flow features and heat transfer characteristics for different values of the governing parameters (unsteadiness parameter, Maxwell parameter, permeability parameter, suction/blowing parameter, thermal radiation parameter, and Prandtl number) are analyzed and discussed in detail.

  5. Paclitaxel Injection

    MedlinePlus

    ... with other medications. Paclitaxel injection manufactured with polyoxyethylated castor oil is used to treat ovarian cancer (cancer that ... cancer, and lung cancer. Paclitaxel injection with polyoxyethylated castor oil is also used to treat Kaposi's sarcoma (a ...

  6. Mipomersen Injection

    MedlinePlus

    ... become pregnant during your treatment, stop using mipomersen injection and call your doctor immediately. ... Mipomersen injection may cause side effects. Tell your doctor if any of these ... and tiredness that are most likely to occur during the first 2 days ...

  7. Levofloxacin Injection

    MedlinePlus

    ... infections. Levofloxacin injection is also used to prevent anthrax (a serious infection that may be spread on ... in people who may have been exposed to anthrax germs in the air. Levofloxacin injection is in ...

  8. Ciprofloxacin Injection

    MedlinePlus

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  9. Romidepsin Injection

    MedlinePlus

    ... with at least one other medication given by mouth or by injection. Romidepsin injection is in a ... antifungals such as itraconazole (Sporanox), ketoconazole (Nizoral), and voriconazole (Vfend); cisapride (Propulsid) (not available in the U.S.); ...

  10. Degarelix Injection

    MedlinePlus

    Degarelix injection is used to treat advanced prostate cancer (cancer that begins in the prostate [a male reproductive gland]). Degarelix injection is in a class of medications called gonadotropin-releasing hormone (GnRH) ...

  11. Paclitaxel Injection

    MedlinePlus

    ... other medications. Paclitaxel injection manufactured with polyoxyethylated castor oil is used to treat ovarian cancer (cancer that ... and lung cancer. Paclitaxel injection with polyoxyethylated castor oil is also used to treat Kaposi's sarcoma (a ...

  12. Glatiramer Injection

    MedlinePlus

    ... course of disease where symptoms flare up from time to time) of multiple sclerosis (MS; a disease in which ... to inject glatiramer, inject it around the same time every day. Follow the directions on your prescription ...

  13. Daratumumab Injection

    MedlinePlus

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    MedlinePlus

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  15. Cefoxitin Injection

    MedlinePlus

    ... injection is used to treat infections caused by bacteria including pneumonia and other lower respiratory tract (lung) ... medications called cephamycin antibiotics. It works by killing bacteria.Antibiotics such as cefoxitin injection will not work ...

  16. Chloramphenicol Injection

    MedlinePlus

    ... treat certain types of serious infections caused by bacteria when other antibiotics cannot be used. Chloramphenicol injection ... antibiotics. It works by stopping the growth of bacteria..Antibiotics such as chloramphenicol injection will not work ...

  17. Oxacillin Injection

    MedlinePlus

    ... is used to treat infections caused by certain bacteria. Oxacillin injection is in a class of medications called penicillins. It works by killing bacteria.Antibiotics such as oxacillin injection will not work ...

  18. Nafcillin Injection

    MedlinePlus

    ... to treat infections caused by certain types of bacteria. Nafcillin injection is in a class of medications called penicillins. It works by killing bacteria.Antibiotics such as nafcillin injection will not work ...

  19. Doripenem Injection

    MedlinePlus

    ... tract, kidney, and abdomen that are caused by bacteria. Doripenem injection is not approved by the Food ... medications called carbapenem antibiotics. It works by killing bacteria.Antibiotics such as doripenem injection will not work ...

  20. Medroxyprogesterone Injection

    MedlinePlus

    ... Medroxyprogesterone injection is a very effective method of birth control but does not prevent the spread of human ... you have been using a different method of birth control and are switching to medroxyprogesterone injection, your doctor ...

  1. Chloramphenicol Injection

    MedlinePlus

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  2. Levoleucovorin Injection

    MedlinePlus

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  3. Estrogen Injection

    MedlinePlus

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    MedlinePlus

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  5. Leuprolide Injection

    MedlinePlus

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    MedlinePlus

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    MedlinePlus

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  8. Epinephrine Injection

    MedlinePlus

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  9. Trastuzumab Injection

    MedlinePlus

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    MedlinePlus

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  11. Doxycycline Injection

    MedlinePlus

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  12. Medroxyprogesterone Injection

    MedlinePlus

    ... Medroxyprogesterone subcutaneous injection is also used to treat endometriosis (a condition in which the type of tissue ... parts of the body in women who have endometriosis. Medroxyprogesterone injection is a very effective method of ...

  13. Ferumoxytol Injection

    MedlinePlus

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  14. Aripiprazole Injection

    MedlinePlus

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  15. 22. Blow Down Valve for Unit 1, view to the ...

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

    22. Blow Down Valve for Unit 1, view to the southwest. This valve allows the water in the draft chest to be lowered (i.e., 'blown down') so that the unit can be motored (i.e., run like an electric motor rather than an electric power generator). The valve is operated by pressure from the instrument air system (part of which is visible in photograph MT-105-A-17 above), but the unit draws on the station air system (see photograph MT-105-A-24 below) to lower the water in the draft chest. - Washington Water Power Clark Fork River Noxon Rapids Hydroelectric Development, Powerhouse, South bank of Clark Fork River at Noxon Rapids, Noxon, Sanders County, MT

  16. Upper-surface-blowing flow-turning performance

    NASA Technical Reports Server (NTRS)

    Sleeman, W. C., Jr.; Phelps, A. E., III

    1976-01-01

    Jet exhaust flow-turning characteristics were determined for systematic variations in upper-surface blowing exhaust nozzles and trailing-edge flap configuration variables from experimental wind-off (static) flow studies. For conditions with parallel flow exhausting from the nozzle, jet height (as indicated by nozzle exit height) and flap radius were found to be the most important parameters relating to flow turning. Nonparallel flow from the nozzle, as obtained from an internal roof angle and/or side spread angle, had a large favorable effect on flow turning. Comparisons made between static turning results and wind tunnel aerodynamic studies of identical configurations indicated that static flow-turning results can be indicative of wind-on powered lift performance for both good and poor nozzle-flap combinations but, for marginal designs, can lead to overly optimistic assessment of powered lift potential.

  17. Blow-down analysis of helium from a cryogenic dewar

    NASA Astrophysics Data System (ADS)

    Khan, H. J.; Zhang, Q. Q.; Rhee, M.; Figueroa, O.

    NASA is currently developing Space Shuttle-based refilling of helium using superfluid helium on-orbit transfer (SHOOT). All the critical components of SHOOT need to be developed through ground-based tests. The helium dewar is one of these components. The Dewar consists of a vacuum vessel enclosing a superinsulated tank. The space between the vacuum vessel and the liquid tank is considered a common vacuum space. In the event that the vacuum is lost, the heat transfers to the dewar and the pressure inside the dewar increases rapidly, resulting in rupture of the dewar due to excessive pressure. Therefore, an emergency vent line is required for release of helium to prevent the dewar from rupturing. The study describes a numerical model for blow-down analysis in an emergency. This qualifies the design of the emergency vent line to be adequate for the assumed heat loads to the helium dewar.

  18. Reduction of Flap Side Edge Noise - the Blowing Flap

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Brooks, THomas F.

    2005-01-01

    A technique to reduce the noise radiating from a wing-flap side edge is being developed. As an airplane wing with an extended flap is exposed to a subsonic airflow, air is blown outward through thin rectangular chord-wise slots at various locations along the side edges and side surface of the flap to weaken and push away the vortices that originate in that region of the flap and are responsible for important noise emissions. Air is blown through the slots at up to twice the local flow velocity. The blowing is done using one or multiple slots, where a slot is located along the top, bottom or side surface of the flap along the side edge, or also along the intersection of the bottom (or top) and side surfaces.

  19. Blow-up and control of marginally separated boundary layers.

    PubMed

    Braun, Stefan; Kluwick, Alfred

    2005-05-15

    Interactive solutions for steady two-dimensional laminar marginally separated boundary layers are known to exist up to a critical value Gamma(c) of the controlling parameter (e.g. the angle of attack of a slender airfoil) Gamma only. Here, we investigate three-dimensional unsteady perturbations of such boundary layers, assuming that the basic flow is almost critical, i.e. in the limit Gamma(c)-Gamma-->0. It is then shown that the interactive equations governing such perturbations simplify significantly, allowing, among others, a systematic study of the blow-up phenomenon observed in earlier investigations and the optimization of devices used in boundary-layer control. PMID:16105768

  20. Soot blower using fuel gas as blowing medium

    DOEpatents

    Tanca, Michael C.

    1982-01-01

    A soot blower assembly (10) for use in combination with a coal gasifier (14). The soot blower assembly is adapted for use in the hot combustible product gas generated in the gasifier as the blowing medium. The soot blower lance (20) and the drive means (30) by which it is moved into and out of the gasifier is housed in a gas tight enclosure (40) which completely surrounds the combination. The interior of the enclosure (40) is pressurized by an inert gas to a pressure level higher than that present in the gasifier so that any combustible product gas leaking from the soot blower lance (20) is forced into the gasifier rather than accumulating within the enclosure.

  1. Skin Friction Reduction by Micro-Blowing Technique

    NASA Technical Reports Server (NTRS)

    Hwang, Danny P. (Inventor)

    1998-01-01

    A system and method for reducing skin friction of an object in relative motion to a fluid. A skin forming a boundary between the object and the fluid, the skin having holes through which micro-blowing of air is blown and a transmitting mechanism for transmitting air through the skin. The skin has an inner layer and an outer layer. the inner layer being a low permeable porous sheet, the outer layer being a plate having high aspect ratio high porosity. and small holes. The system may further include a suction apparatus for suctioning air from the outer layer. The method includes the steps of transmitting air through the inner layer and passing the air transmitted through the inner layer to the outer layer. The method may further include the step of bleeding air off the outer layer using the suction apparatus.

  2. Wagon loads of sand blows in White County, Illinois

    USGS Publications Warehouse

    Hough, S.E.; Bilham, R.; Mueller, K.; Stephenson, W.; Williams, R.; Odum, J.

    2005-01-01

    Several anecdotal accounts provide compelling evidence that liquefaction occurred at several sites in Illinois during the 1811-1812 New Madrid sequence, as much as 250 km north of the New Madrid seismic zone (NMSZ). At one Wabash Valley location, sand blows are still evident near Big Prairie, Illinois, a location described in a particularly detailed and precise historic account. This account includes descriptions of substantial liquefaction (sand blows) as well as a two-mile-long east-west-trending "crack" along which two feet of south-side-down displacement occurred. An offset can no longer be seen at this location, which has been extensively farmed and plowed for decades. Field reconnaissance verifies many of the details provided in the account, however. We conducted a seismic-reflection experiment at this location and observed a modest offset in the Paleozoic strata at this location. The offset is opposite to that described in the historic account, consistent with the hypothesis that large midcontinent earthquakes occur on faults reactivated in a Holocene stress regime different from the one in which they were formed. Only two explanations can account for these observations: Either large NMSZ events triggered substantial liquefaction at distances greater than hitherto realized, or at least one large "New Madrid" event occurred significantly north of the NMSZ. We explore these possibilities and conclude that, while neither one can be ruled out, several disparate lines of evidence suggest that the 23 January 1812 "New Madrid mainshock" occurred in White County, Illinois, near the location of the mb 5.5 1968 southern Illinois earthquake and recent microearthquake activity.

  3. Investigation of pulsed light for terminal sterilization of WFI filled blow/fill/seal polyethylene containers.

    PubMed

    Dunn, J; Burgess, D; Leo, F

    1997-01-01

    A study was performed to assess the ability of pulsed light to sterilize water for injection in blow/fill/seal polyethylene containers. Pulsed light uses intense, short duration flashes of broad spectrum white light to produce high levels of microbial kill. In a first phase of testing, containers of 0.5, 5, 15, and 120 mL nominal volume were inoculated with Bacillus pumilus endospores, Bacillus subtilus variety niger strain globigii endospores, Bacillus stearothermophilus endospores, and Aspergillus niger conidiospores. Approximately 10(6) colony forming units of each test spore were individually inoculated into 22 replicate containers of each sample volume. Two of these containers served as inoculation recovery controls, and 10 were treated using each of two pulsed light exposure methods: single-sided treatment, or treatment within a reflective cavity. Both treatments employed flashes of intense broad spectrum pulsed light delivered at one flash per second. Cavity treatment used 10 flashes to treat each container within a reflective cavity containing a single lamp. Cavity treatment yielded no recoverable survivors for any of the challenge spores from the contents of any of the 160 total samples. Single-sided treatment used 20 approximately 1-J/cm2 flashes from a single lamp-reflector projecting onto one side of the container. Single-sided treatment yielded no recoverable survivors from the contents of the containers for any of the bacterial endospores tested, but Aspergillus niger survival was detected in 4 of the 40 single-side treated samples. A second phase of tests examined the pulsed light inactivation of Bacillus pumilus spores for a range of inoculation levels. High levels of Bacillus pumilus spore kill were obtained using only a few cavity flashes. The results show that pulsed light can provide high levels of microbial lethality and possesses potential for use as a terminal sterilization method for water for injection in filled, sealed polyethylene

  4. Cloud Network Helps Stretch IT Dollars

    ERIC Educational Resources Information Center

    Collins, Hilton

    2012-01-01

    No matter how many car washes or bake sales schools host to raise money, adding funds to their coffers is a recurring problem. This perpetual financial difficulty makes expansive technology purchases or changes seem like a pipe dream for school CIOs and has education technologists searching for ways to stretch money. In 2005, state K-12 school…

  5. Project Stretch Final Narrative Report. Year III.

    ERIC Educational Resources Information Center

    American Camping Association, Martinsville, IN.

    In June, 1979, the American Camping Association implemented Project STRETCH (Strategies to Try out Resources to Enhance the Training of Camp Directors serving the Handicapped), a nationwide in-service training program for personnel providing services to handicapped children and youth in regularly and specially designed camping and outdoor…

  6. How to determine local stretching and tension in a flow-stretched DNA molecule

    NASA Astrophysics Data System (ADS)

    Pedersen, Jonas N.; Marie, Rodolphe; Kristensen, Anders; Flyvbjerg, Henrik

    We determine the nonuniform stretching of and tension in a Mbp-long fragment of DNA that is flow-stretched in a nanofluidic chip. We use no markers, do not know the contour length of the DNA, and do not have the full DNA molecule inside our field-of-view. Instead we analyze the transverse thermal motion of the DNA. Tension at the center of the DNA adds up to 16 pN, giving almost fully stretched DNA. Fitted parameters agree well with simplified expressions, where the DNA is modeled as a cylinder in a parallel flow.

  7. Suppression of Dynamic Stall by Steady and Pulsed Upper-Surface Blowing

    NASA Technical Reports Server (NTRS)

    Weaver, D.; McAlister, K. W.; Tso, J.

    1996-01-01

    The Boeing-Vertol VR-7 airfoil was experimentally studied with steady and pulsed upper-surface blowing for sinusoidal pitching oscillations described by alpha = alpha(sub m) + 10 deg sin(omega t). The tests were conducted in the U.S. Army Aeroflightdynamics Directorate's Water Tunnel at NASA Ames Research Center. The experiment was performed at a Reynolds number of 100,000. Pitch oscillations with alpha(sub m) = 10 deg and 15 deg and with reduced frequencies ranging from k = 0.005 to 0.15 were examined. Blowing conditions ranged from C(sub mu) = 0.03 to 0.66 and F(+) = 0 to 3. Unsteady lift, drag, and pitching-moment loads were measured, and fluorescent-dye flow visualizations were obtained. Steady, upper-surface blowing was found to be capable of trapping a separation bubble near the leading edge during a portion of the airfoil's upward rotation. When this occurred, the lift was increased significantly and stall was averted. In all cases, steady blowing reduced the hysteresis amplitudes present in the loads and produced a large thrust force. The benefits of steady blowing diminished as the reduced frequency and mean angle of oscillation increased. Pulsed blowing showed only marginal benefits for the conditions tested. The greatest gains from pulsed blowing were achieved at F(+) = 0.9.

  8. Effect of blowing agents on the oxidation resistance of carbon foams prepared from molten sucrose

    NASA Astrophysics Data System (ADS)

    Narasimman, R.; Prabhakaran, K.

    2013-06-01

    We have prepared low density carbon foams from molten sucrose using aluminium nitrate and boric acid blowing agents. A comparative study of the oxidation resistance of the carbon foams prepared using the two blowing agents are reported in the present paper. Oxidation of the carbon foams was evaluated under isothermal and non-isothermal conditions in air atmosphere using thermogravimetric analysis (TGA). We have observed that the alumina produced from the aluminium nitrate blowing agent acts as a catalyst whereas the boron produced from boric acid inhibits the oxidation of the carbon foams. The oxidation resistance of carbon foams increases with boron concentration. The oxidation onset temperature for the carbon foams prepared using boric acid blowing agent was nearly 60°C higher than that prepared using aluminium nitrate blowing agent. Carbon foams prepared using aluminium nitrate blowing agent undergoes complete oxidation at temperature less than 700°C. Whereas that prepared using boric acid blowing agent leave ˜ 50 wt.% residue at 900°C. Further evidence is provided by the kinetic analysis of the TGA using Coats-Redfern (CR) equation.

  9. Turbulent boundary layer control at moderate Reynolds numbers by means of uniform blowing/suction

    NASA Astrophysics Data System (ADS)

    Kametani, Yukinori; Fukagata, Koji; Orlu, Ramis; Schlatter, Philipp

    2015-11-01

    The effect of uniform blowing or suction from the wall on a spatially developing turbulent boundary layer has been studied in order to use them ultimately for flow control on the surface of high-speed vehicles. In the present study, a series of large eddy simulations is performed to investigate the effects of uniform blowing/suction on the skin friction drag as well as the scale of turbulent structures at moderate Reynolds numbers up to Reθ = 2500, based on free-stream velocity, U∞, and momentum thickness, θ. The amplitude of blowing or suction is fixed to 0.1% of U∞with different streamwise ranges of the control region. While the Reynolds shear and normal stresses and their spectral energy distributions are increased by blowing and decreased by suction, in particular, in the outer region, the FIK identity reveals that drag reduction (DR) or enhancement (DE) are mainly linked to changes in the spatial development of the mean wall-normal convection term rather than the contribution from the Reynolds shear stress. Despite the weak amplitude of the control, over 10% of DR and DE are achieved by blowing and suction, respectively. In case of blowing, the mean DR rate increases as the blowing region extends because the local reduction rate grows in the streamwise direction. Grant-in-Aid for Scientific Research (C) (No. 25420129), Grant-in-Aid for JSPS Fellow (No. 24-3450), the Knut an Alice Wallenberg Foundation.

  10. Influence of particles shape on the vertical profile of blowing snow concentration

    NASA Astrophysics Data System (ADS)

    Vionnet, Vincent; Trouvilliez, Alexandre; Naaim-Bouvet, Florence; Guyomarc'h, Gilbert

    2013-04-01

    In alpine regions, blowing snow events strongly influence the temporal and spatial evolution of the snow cover throughout the winter season. In Antarctica, blowing snow is an essential surface mass balance process and plays a non-negligible role in the annual accumulation. The vertical profile of blowing snow concentration determines the quantity of snow transported in turbulent suspension. A power law is often used to represent this vertical profile. It serves as an analytical solution representing an equilibrium between vertical turbulent diffusion and gravitational settling. In this work, we study how the exponent of the power law depends on the type of transported particles. Vertical profiles of blowing snow concentration have been collected at the experimental site of Col du Lac Blanc (French Alps) in 2011 and 2012 and near the research station of Cap Prud'homme (Antarctica) in 2010 and 2011. We used mechanical gauges (butterfly nets) and optical devices (Snow Particles Counters). Profiles collected during blowing snow events with precipitation have been corrected to account for the contribution of snowfall. Results show that profiles collected during blowing snow without snowfall differ from the corrected profiles collected during snowfall. At a given wind speed, particles transported during snowfall have a lower settling velocity than particles transported without snowfall. This difference confirms earlier observations (Takahashi, 1985) and can be explained by the change of drag coefficient between dendritic and rounded particles. This difference pertains several hours after the end of the snowfall illustrating the fragmentation of snow grains during blowing snow events.

  11. Roll-yaw control at high angle of attack by forebody tangential blowing

    NASA Technical Reports Server (NTRS)

    Pedreiro, N.; Rock, S. M.; Celik, Z. Z.; Roberts, L.

    1995-01-01

    The feasibility of using forebody tangential blowing to control the roll-yaw motion of a wind tunnel model is experimentally demonstrated. An unsteady model of the aerodynamics is developed based on the fundamental physics of the flow. Data from dynamic experiments is used to validate the aerodynamic model. A unique apparatus is designed and built that allows the wind tunnel model two degrees of freedom, roll and yaw. Dynamic experiments conducted at 45 degrees angle of attack reveal the system to be unstable. The natural motion is divergent. The aerodynamic model is incorporated into the equations of motion of the system and used for the design of closed loop control laws that make the system stable. These laws are proven through dynamic experiments in the wind tunnel using blowing as the only actuator. It is shown that asymmetric blowing is a highly non-linear effector that can be linearized by superimposing symmetric blowing. The effects of forebody tangential blowing and roll and yaw angles on the flow structure are determined through flow visualization experiments. The transient response of roll and yaw moments to a step input blowing are determined. Differences on the roll and yaw moment dependence on blowing are explained based on the physics of the phenomena.

  12. Roll-Yaw control at high angle of attack by forebody tangential blowing

    NASA Technical Reports Server (NTRS)

    Pedreiro, N.; Rock, S. M.; Celik, Z. Z.; Roberts, L.

    1995-01-01

    The feasibility of using forebody tangential blowing to control the roll-yaw motion of a wind tunnel model is experimentally demonstrated. An unsteady model of the aerodynamics is developed based on the fundamental physics of the flow. Data from dynamic experiments is used to validate the aerodynamic model. A unique apparatus is designed and built that allows the wind tunnel model two degrees of freedom, roll and yaw. Dynamic experiments conducted at 45 degrees angle of attack reveal the system to be unstable. The natural motion is divergent. The aerodynamic model is incorporated into the equations of motion of the system and used for the design of closed loop control laws that make the system stable. These laws are proven through dynamic experiments in the wind tunnel using blowing as the only actuator. It is shown that asymmetric blowing is a highly non-linear effector that can be linearized by superimposing symmetric blowing. The effects of forebody tangential blowing and roll and yaw angles on the flow structure are determined through flow visualization experiments. The transient response of roll and yaw moments to a step input blowing are determined. Differences on the roll and yaw moment dependence on blowing are explained based on the physics of the phenomena.

  13. How to determine local stretching and tension in a flow-stretched DNA molecule

    NASA Astrophysics Data System (ADS)

    Pedersen, Jonas N.; Marie, Rodolphe; Kristensen, Anders; Flyvbjerg, Henrik

    2016-04-01

    We determine the nonuniform stretching of and tension in a mega base pairs-long fragment of deoxyribonucleic acid (DNA) that is flow stretched in a nanofluidic chip. We use no markers, do not know the contour length of the DNA, and do not have the full DNA molecule inside our field of view. Instead, we analyze the transverse thermal motion of the DNA. Tension at the center of the DNA adds up to 16 pN, giving almost fully stretched DNA. This method was devised for optical mapping of DNA, specifically, DNA denaturation patterns. It may be useful also for other studies, e.g., DNA-protein interactions, specifically, their tension dependence. Generally, wherever long strands of DNA—e.g., native DNA extracted from human cells or bacteria—must be stretched with ease for inspection, this method applies.

  14. Numerical study of the trailing vortex of a wing with wing-tip blowing

    NASA Technical Reports Server (NTRS)

    Lim, Hock-Bin

    1994-01-01

    Trailing vortices generated by lifting surfaces such as helicopter rotor blades, ship propellers, fixed wings, and canard control surfaces are known to be the source of noise, vibration, cavitation, degradation of performance, and other hazardous problems. Controlling these vortices is, therefore, of practical interest. The formation and behavior of the trailing vortices are studied in the present research. In addition, wing-tip blowing concepts employing axial blowing and spanwise blowing are studied to determine their effectiveness in controlling these vortices and their effects on the performance of the wing. The 3D, unsteady, thin-layer compressible Navier-Stokes equations are solved using a time-accurate, implicit, finite difference scheme that employs LU-ADI factorization. The wing-tip blowing is simulated using the actuator plane concept, thereby, not requiring resolution of the jet slot geometry. Furthermore, the solution blanking feature of the chimera scheme is used to simplify the parametric study procedure for the wing-tip blowing. Computed results are shown to compare favorably with experimental measurements. It is found that axial wing-tip blowing, although delaying the rolling-up of the trailing vortices and the near-field behavior of the flowfield, does not dissipate the circulation strength of the trailing vortex farther downstream. Spanwise wing-tip blowing has the effect of displacing the trailing vortices outboard and upward. The increased 'wing-span' due to the spanwise wing-tip blowing has the effect of lift augmentation on the wing and the strengthening of the trailing vortices. Secondary trailing vortices are created at high spanwise wing-tip blowing intensities.

  15. Oxygen and carbon discovered in exoplanet atmosphere `blow-off'

    NASA Astrophysics Data System (ADS)

    2004-02-01

    Oxygen and carbon discovered in exoplanet atmosphere ‘blow-off’ hi-res Size hi-res: 1096 kb Credits: ESA/Alfred Vidal-Madjar (Institut d’Astrophysique de Paris, CNRS, France) Oxygen and carbon discovered in exoplanet atmosphere ‘blow-off’ This artist’s impression shows an extended ellipsoidal envelope - the shape of a rugby-ball - of oxygen and carbon discovered around the well-known extrasolar planet HD 209458b. An international team of astronomers led by Alfred Vidal-Madjar (Institut d’Astrophysique de Paris, CNRS, France) observed the first signs of oxygen and carbon in the atmosphere of a planet beyond our Solar System for the first time using the NASA/ESA Hubble Space Telescope. The atoms of carbon and oxygen are swept up from the lower atmosphere with the flow of escaping atmospheric atomic hydrogen - like dust in a supersonic whirlwind - in a process called atmospheric ‘blow off’. Oxygen and carbon have been detected in the atmosphere of a planet beyond our Solar System for the first time. Scientists using the NASA/ESA Hubble Space Telescope have observed the famous extrasolar planet HD 209458b passing in front of its parent star, and found oxygen and carbon surrounding the planet in an extended ellipsoidal envelope - the shape of a rugby-ball. These atoms are swept up from the lower atmosphere with the flow of the escaping atmospheric atomic hydrogen, like dust in a supersonic whirlwind. The team led by Alfred Vidal-Madjar (Institut d’Astrophysique de Paris, CNRS, France) reports this discovery in a forthcoming issue of Astrophysical Journal Letters. The planet, called HD 209458b, may sound familiar. It is already an extrasolar planet with an astounding list of firsts: the first extrasolar planet discovered transiting its sun, the first with an atmosphere, the first observed to have an evaporating hydrogen atmosphere (in 2003 by the same team of scientists) and now the first to have an atmosphere containing oxygen and carbon. Furthermore

  16. Stable Self-Similar Blow-Up Dynamics for Slightly {L^2}-Supercritical Generalized KDV Equations

    NASA Astrophysics Data System (ADS)

    Lan, Yang

    2016-07-01

    In this paper we consider the slightly {L^2}-supercritical gKdV equations {partial_t u+(u_{xx}+u|u|^{p-1})_x=0}, with the nonlinearity {5 < p < 5+\\varepsilon} and {0 < \\varepsilon≪ 1}. We will prove the existence and stability of a blow-up dynamics with self-similar blow-up rate in the energy space {H^1} and give a specific description of the formation of the singularity near the blow-up time.

  17. On the blow-up solutions for the nonlinear fractional Schrödinger equation

    NASA Astrophysics Data System (ADS)

    Zhu, Shihui

    2016-07-01

    This paper is dedicated to the blow-up solutions for the nonlinear fractional Schrödinger equation arising from pseudorelativistic Boson stars. First, we compute the best constant of a gG-N inequality by the profile decomposition theory and variational arguments. Then, we find the sharp threshold mass of the existence of finite-time blow-up solutions. Finally, we study the dynamical properties of finite-time blow-up solutions around the sharp threshold mass by giving a refined compactness lemma.

  18. An experimental investigation of leading-edge vortex augmentation by blowing

    NASA Technical Reports Server (NTRS)

    Bradley, R. G.; Wray, W. O.; Smith, C. W.

    1974-01-01

    A wind tunnel test was conducted to determine the effects of over-the-wing blowing as a means of augmenting the leading-edge vortex flow of several pointed-tip, sharp-edged planforms. Arrow, delta, and diamond wings with leading-edge sweeps of 30 and 45 degrees were mounted on a body-of-revolution fuselage and tested in a low-speed wind tunnel at a Mach number of 0.2. Nozzle location data, pitch data, and flow-visualization pictures were obtained for a range of blowing rates. Results show pronounced increases in vortex lift due to the blowing.

  19. Flap noise measurements for STOL configurations using external upper surface blowing

    NASA Technical Reports Server (NTRS)

    Dorsch, R. G.; Reshotko, M.; Olsen, W. A.

    1972-01-01

    Screening tests of upper surface blowing on externally blown flaps configurations were conducted. Noise and turning effectiveness data were obtained with small-scale, engine-over-the-wing models. One large model was tested to determine scale effects. Nozzle types included circular, slot, D-shaped, and multilobed. Tests were made with and without flow attachment devices. For STOL applications the particular multilobed mixer and the D-shaped nozzles tested were found to offer little or no noise advantage over the round convergent nozzle. High aspect ratio slot nozzles provided the quietest configurations. In general, upper surface blowing was quieter than lower surface blowing for equivalent EBF models.

  20. NORTHERLY STRETCH OF MILLBURY PORTION; GENERAL VIEW ACROSS CANAL PRISM ...

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

    NORTHERLY STRETCH OF MILLBURY PORTION; GENERAL VIEW ACROSS CANAL PRISM TO TOWPATH BERM (LATER FILL ENCROACHING LEFT) NEAR CENTER OF THIS STRETCH; VIEW TO SOUTHWEST - Blackstone Canal Worcester-Millbury Segment, Eastern bank of Blackstone River, Millbury, Worcester County, MA

  1. Stretching a self-interacting semiflexible polymer

    NASA Astrophysics Data System (ADS)

    Rosa, A.; Marenduzzo, D.; Kumar, S.

    2006-09-01

    We present results from three-dimensional off-lattice Monte Carlo simulations to investigate the stretching response of a semi-flexible polymer subjected to self-attractive interactions. We employ the quasi-static approximation and consider both the fixed elongation and the fixed force ensemble, which can equally well be reproduced in experiments nowadays. The force vs. elongation curves are in general non-monotonic, and the quantity and height of peaks increase with decreasing temperature, and with increasing stiffness. We finally compute the variation of unfolding force with temperature. Our results should be relevant for stretching experimental studies, and for more refined theoretical modeling, taking non-equilibrium and kinetic effects into account.

  2. Stretching cells and delivering drugs with bubbles

    NASA Astrophysics Data System (ADS)

    Ohl, Claus-Dieter; Li, Fenfang; Chon U, Chan; Gao, Yu; Xu, Chenjie

    2015-11-01

    In this talk we'll review our work on impulsive cell stretching using cavitation bubbles and magnetic microbubbles for drug delivery. For sufficient short times cells can sustain a much larger areal strain than the yield strain obtained from quasi-static stretching. Experiments with red blood cells show that even then the rupture of the cell is slow process; it is caused by diffusive swelling rather than mechanical violation of the plasma membrane. In the second part we'll discuss bubbles coated with magnetic and drug loaded particles. These bubbles offer an interesting vector for on demand delivery of drugs using mild ultrasound and magnetic fields. We report on basic experiments in microfluidic channels revealing the release of the agent during bubble oscillations and first in vivo validation with a mouse tumor model. Singapore National Research Foundations Competitive Research Program funding (NRF-CRP9-2011-04).

  3. Modeling aftershocks as a stretched exponential relaxation

    NASA Astrophysics Data System (ADS)

    Mignan, A.

    2015-11-01

    The decay rate of aftershocks has been modeled as a power law since the pioneering work of Omori in the late nineteenth century. Although other expressions have been proposed in recent decades to describe the temporal behavior of aftershocks, the number of model comparisons remains limited. After reviewing the aftershock models published from the late nineteenth century until today, I solely compare the power law, pure exponential and stretched exponential expressions defined in their simplest forms. By applying statistical methods recommended recently in applied mathematics, I show that all aftershock sequences tested in three regional earthquake catalogs (Southern and Northern California, Taiwan) and with three declustering techniques (nearest-neighbor, second-order moment, window methods) follow a stretched exponential instead of a power law. These results infer that aftershocks are due to a simple relaxation process, in accordance with most other relaxation processes observed in Nature.

  4. Vibrational overtone stretching transitions in sarin

    NASA Astrophysics Data System (ADS)

    Petryk, Michael W. P.

    2006-10-01

    The CH stretching overtone transitions of the nerve agent sarin (O-isopropyl methylphosphonofluoridate) are of interest to the standoff detection of chemical warfare agents, as many of these transitions occur near regions where small, efficient, portable diode lasers (originally developed for use in the telecommunications industry) operate. However, the interpretation of experimental vibrational overtone spectra is often difficult, and the computational simulation of overtone transitions in a molecule is challenging. Presented herein are the simulated CH overtone stretching transitions in sarin. Spectral regions are simulated from overtone transition energies and intensities, both of which are calculated within the harmonically coupled anharmonic oscillator (HCAO) model. Data for HCAO calculations are obtained from ab initio calculations, without any recourse to experimental data.

  5. NASA/MSFC Large Stretch Press Study

    NASA Technical Reports Server (NTRS)

    Choate, M. W.; Nealson, W. P.; Jay, G. C.; Buss, W. D.

    1985-01-01

    The purpose of this study was to: A. assess and document the advantages/disadvantages of a government agency investment in a large stretch form press on the order of 5000 tons capacity (per jaw); B. develop a procurement specification for the press; and C. provide trade study data that will permit an optimum site location. Tasks were separated into four major elements: cost study, user survey, site selection, and press design/procurement specification.

  6. Stretch-induced cervicobrachial pain syndrome.

    PubMed

    Quintner, J

    1990-01-01

    The case records of 22 patients who presented with severe and persistent cervicobrachial pain were reviewed. The onset of their pain followed the performance of a forceful activity (lifting, pulling or pushing) using one or both arms in the outstretched position. Their symptoms and the findings on physical examination were both consistent with stretch-induced damage to neural tissues related to the painful upper limb. The predominant site of painful neural pathology appeared to be within the cervical spine. PMID:25025877

  7. Image enhancement by local histogram stretching

    NASA Astrophysics Data System (ADS)

    Alparslan, E.; Fuatince, Mr.

    1981-05-01

    An image enhancement algorithm that makes use of local histogram stretching is introduced. This algorithm yields considerable improvements in human observation of details in an image, compared to straightforward histogram equalization and a number of other enhancement techniques. The algorithm is especially suitable for producing hard copies of images on electrostatic plotters with limited gray levels, as shown in applications to the Girl's image and a Landsat image.

  8. Turbine vane gas film cooling with injection in the leading edge region from a single row of spanwise angled holes

    NASA Technical Reports Server (NTRS)

    Lecuyer, M. R.; Hanus, G. J.

    1976-01-01

    An experimental study of gas film cooling was conducted on a 3X size model turbine vane. Injection in the leading edge region was from a single row of holes angled in a spanwise direction. Measurements of the local heat flux downstream from the row of coolant holes, both with and without film coolant flow, were used to determine the film cooling performance presented in terms of the Stanton number ratio. Results for a range of coolant blowing ratio, M = 0 to 2.0, indicate a reduction in heat flux of up to 15 to 30 percent at a point 10 to 11 hole diameters downstream from injection. An optimum coolant blowing ratio corresponds to a coolant-to-freestream velocity ratio in the range of 0.5. The shallow injection angle resulted in superior cooling performance for injection closest to stagnation, while the effect of injection angle was insignificant for injection further from stagnation.

  9. Stretch Moduli of Ribonucleotide Embedded Short DNAs

    NASA Astrophysics Data System (ADS)

    Chiu, Hsiang-Chih; Koh, Kyung Duk; Riedo, Elisa; Storici, Francesca

    2013-03-01

    Understanding the mechanical properties of DNA is essential to comprehending the dynamics of many cellular functions. DNA deformations are involved in many mechanisms when genetic information needs to be stored and used. In addition, recent studies have found that Ribonucleotides (rNMPs) are among the most common non-standard nucleotides present in DNA. The presences of rNMPs in DNA might cause mutation, fragility or genotoxicity of chromosome but how they influence the structure and mechanical properties of DNA remains unclear. By means of Atomic Force Microscopy (AFM) based single molecule spectroscopy, we measure the stretch moduli of double stranded DNAs (dsDNA) with 30 base pairs and 5 equally embedded rNMPs. The dsDNAs are anchored on gold substrate via thiol chemistry, while the AFM tip is used to pick up and stretch the dsDNA from its free end through biotin-streptavidin bonding. Our preliminary results indicate that the inclusion of rNMPs in dsDNA might significantly change its stretch modulus, which might be important in some biological processes.

  10. Dynamics and structure of stretched flames

    SciTech Connect

    Law, C.K.

    1993-12-01

    This program aims to gain fundamental understanding on the structure, geometry, and dynamics of laminar premixed flames, and relate these understanding to the practical issues of flame extinction and stabilization. The underlying fundamental interest here is the recent recognition that the response of premixed flames can be profoundly affected by flame stretch, as manifested by flow nonuniformity, flame curvature, and flame/flow unsteadiness. As such, many of the existing understanding on the behavior of premixed flames need to be qualitatively revised. The research program consists of three major thrusts: (1) detailed experimental and computational mapping of the structure of aerodynamically-strained planar flames, with emphasis on the effects of heat loss, nonequidiffusion, and finite residence time on the flame thickness, extent of incomplete reaction, and the state of extinction. (2) Analytical study of the geometry and dynamics of stretch-affected wrinkled flame sheets in simple configurations, as exemplified by the Bunsen flame and the spatially-periodic flame, with emphasis on the effects of nonlinear stretch, the phenomena of flame cusping, smoothing, and tip opening, and their implications on the structure and burning rate of turbulent flames. (3) Stabilization and blowoff of two-dimensional inverted premixed and stabilization and determining the criteria governing flame blowoff. The research is synergistically conducted through the use of laser-based diagnostics, computational simulation of the flame structure with detailed chemistry and transport, and mathematical analysis of the flame dynamics.

  11. Numerical and experimental study of blowing jet on a high lift airfoil

    NASA Astrophysics Data System (ADS)

    Bobonea, A.; Pricop, M. V.

    2013-10-01

    Active manipulation of separated flows over airfoils at moderate and high angles of attack in order to improve efficiency or performance has been the focus of a number of numerical and experimental investigations for many years. One of the main methods used in active flow control is the usage of blowing devices with constant and pulsed blowing. Through CFD simulation over a 2D high-lift airfoil, this study is trying to highlight the impact of pulsed blowing over its aerodynamic characteristics. The available wind tunnel data from INCAS low speed facility are also beneficial for the validation of the numerical analysis. This study intends to analyze the impact of the blowing jet velocity and slot geometry on the efficiency of an active flow control.

  12. On lower bounds for possible blow-up solutions to the periodic Navier-Stokes equation

    SciTech Connect

    Cortissoz, Jean C. Montero, Julio A. Pinilla, Carlos E.

    2014-03-15

    We show a new lower bound on the H{sup .3/2} (T{sup 3}) norm of a possible blow-up solution to the Navier-Stokes equation, and also comment on the extension of this result to the whole space. This estimate can be seen as a natural limiting result for Leray's blow-up estimates in L{sup p}(R{sup 3}), 3 < p < ∞. We also show a lower bound on the blow-up rate of a possible blow-up solution of the Navier-Stokes equation in H{sup .5/2} (T{sup 3}), and give the corresponding extension to the case of the whole space.

  13. Generating Soap Bubbles by Blowing on Soap Films.

    PubMed

    Salkin, Louis; Schmit, Alexandre; Panizza, Pascal; Courbin, Laurent

    2016-02-19

    Making soap bubbles by blowing air on a soap film is an enjoyable activity, yet a poorly understood phenomenon. Working either with circular bubble wands or long-lived vertical soap films having an adjustable steady state thickness, we investigate the formation of such bubbles when a gas is blown through a nozzle onto a film. We vary film size, nozzle radius, space between the film and nozzle, and gas density, and we measure the gas velocity threshold above which bubbles are formed. The response is sensitive to containment, i.e., the ratio between film and jet sizes, and dissipation in the turbulent gas jet, which is a function of the distance from the film to the nozzle. We rationalize the observed four different regimes by comparing the dynamic pressure exerted by the jet on the film and the Laplace pressure needed to create the curved surface of a bubble. This simple model allows us to account for the interplay between hydrodynamic, physicochemical, and geometrical factors. PMID:26943558

  14. Flutter Stability Verified for the Trailing Edge Blowing Fan

    NASA Technical Reports Server (NTRS)

    Bakhle, Milind A.; Srivastava, Rakesh

    2005-01-01

    The TURBO-AE aeroelastic code has been used to verify the flutter stability of the trailing edge blowing (TEB) fan, which is a unique technology demonstrator being designed and fabricated at the NASA Glenn Research Center for testing in Glenn s 9- by 15-Foot Low-Speed Wind Tunnel. Air can be blown out of slots near the trailing edges of the TEB fan blades to fill in the wakes downstream of the rotating blades, which reduces the rotor-stator interaction (tone) noise caused by the interaction of wakes with the downstream stators. The TEB fan will demonstrate a 1.6-EPNdB reduction in tone noise through wake filling. Furthermore, the reduced blade-row interaction will decrease the possibility of forced-response vibrations and enable closer spacing of blade rows, thus reducing engine length and weight. The detailed aeroelastic analysis capability of the three-dimensional Navier-Stokes TURBO-AE code was used to check the TEB fan rotor blades for flutter stability. Flutter calculations were first performed with no TEB flow; then select calculations were repeated with TEB flow turned on.

  15. High speed aerodynamics of upper surface blowing aircraft configurations

    NASA Technical Reports Server (NTRS)

    Birckelbaw, Larry D.

    1992-01-01

    An experimental investigation of the high speed aerodynamics of Upper Surface Blowing (USB) aircraft configurations has been conducted to accurately define the magnitude and causes of the powered configuration cruise drag. A highly instrumented wind tunnel model of a realistic USB configuration was used which permitted parametric variations in the number and spanwise location of the nacelles and was powered with two turbofan engine simulators. The tests conducted in the Ames 14 Foot Transonic Wind Tunnel examined 10 different configurations at Mach numbers from 0.5 to 0.775, fan nozzle pressure ratios from 1.1 to 2.1 and angles of attack from -4 to 6 degrees. Measured force data is presented which indicates the cruise drag penalty associated with each configuration and surface pressure contour plots are used to illustrate the underlying flowfield physics. It was found that all of the tested configurations suffered from a severe drag penalty which increased with freestream Mach number, power setting and angle of attack and was associated with the presence of strong shocks and regions of separated flow in the wing/nacelle junction regions.

  16. Landauer's blow-torch effect in systems with entropic potential.

    PubMed

    Das, Moupriya; Ray, Deb Shankar

    2015-11-01

    We consider local heating of a part of a two-dimensional bilobal enclosure of a varying cross section confining a system of overdamped Brownian particles. Since varying cross section in higher dimension results in an entropic potential in lower dimension, local heating alters the relative stability of the entropic states. We show that this blow-torch effect modifies the entropic potential in a significant way so that the resultant effective entropic potential carries both the features of variation of width of the confinement and variation of temperature along the direction of transport. The reduced probability distribution along the direction of transport calculated by full numerical simulations in two dimensions agrees well with our analytical findings. The extent of population transfer in the steady state quantified in terms of the integrated probability of residence of the particles in either of the two lobes exhibits interesting variation with the mean position of the heated region. Our study reveals that heating around two particular zones of a given lobe maximizes population transfer to the other. PMID:26651672

  17. Landauer's blow-torch effect in systems with entropic potential

    NASA Astrophysics Data System (ADS)

    Das, Moupriya; Ray, Deb Shankar

    2015-11-01

    We consider local heating of a part of a two-dimensional bilobal enclosure of a varying cross section confining a system of overdamped Brownian particles. Since varying cross section in higher dimension results in an entropic potential in lower dimension, local heating alters the relative stability of the entropic states. We show that this blow-torch effect modifies the entropic potential in a significant way so that the resultant effective entropic potential carries both the features of variation of width of the confinement and variation of temperature along the direction of transport. The reduced probability distribution along the direction of transport calculated by full numerical simulations in two dimensions agrees well with our analytical findings. The extent of population transfer in the steady state quantified in terms of the integrated probability of residence of the particles in either of the two lobes exhibits interesting variation with the mean position of the heated region. Our study reveals that heating around two particular zones of a given lobe maximizes population transfer to the other.

  18. Generating Soap Bubbles by Blowing on Soap Films

    NASA Astrophysics Data System (ADS)

    Salkin, Louis; Schmit, Alexandre; Panizza, Pascal; Courbin, Laurent

    2016-02-01

    Making soap bubbles by blowing air on a soap film is an enjoyable activity, yet a poorly understood phenomenon. Working either with circular bubble wands or long-lived vertical soap films having an adjustable steady state thickness, we investigate the formation of such bubbles when a gas is blown through a nozzle onto a film. We vary film size, nozzle radius, space between the film and nozzle, and gas density, and we measure the gas velocity threshold above which bubbles are formed. The response is sensitive to containment, i.e., the ratio between film and jet sizes, and dissipation in the turbulent gas jet, which is a function of the distance from the film to the nozzle. We rationalize the observed four different regimes by comparing the dynamic pressure exerted by the jet on the film and the Laplace pressure needed to create the curved surface of a bubble. This simple model allows us to account for the interplay between hydrodynamic, physicochemical, and geometrical factors.

  19. An experimental investigation of delta wing vortex flow with and without external jet blowing

    NASA Technical Reports Server (NTRS)

    Iwanski, Kenneth P.; Ng, T. Terry; Nelson, Robert C.

    1989-01-01

    A visual and quantitative study of the vortex flow field over a 70-deg delta wing with an external jet blowing parallel to and at the leading edge was conducted. In the experiment, the vortex core was visually marked with TiCl4, and LDA was used to measure the velocity parallel and normal to the wing surface. It is found that jet blowing moved vortex breakdown farther downstream from its natural position and influenced the breakdown characteristics.

  20. Blowout fracture of the orbital floor secondary to vigorous nose blowing.

    PubMed

    Halpenny, D; Corbally, C; Torreggiani, W

    2012-01-01

    Orbital floor fracture due to vigorous nose blowing in the absence of mechanical trauma is rare, only four cases having previously been reported. In each of these cases, predisposing factors have been identified; preceding URTI in three and a history of sino-nasal surgery in the fourth case. We present the case of a 49-year-old woman who developed a maxillary sinus fracture and orbital emphysema after blowing her nose. PMID:23008887

  1. Lacosamide Injection

    MedlinePlus

    ... may be prescribed for other uses; ask your doctor or pharmacist for more information. ... Before using lacosamide injection,tell your doctor and pharmacist if you are allergic to lacosamide, any other medications, or any of the ingredients in lacosamide injection. Ask your pharmacist for a ...

  2. Dexamethasone Injection

    MedlinePlus

    ... lines under the skin skin depressions at the injection site increased body fat or movement to different areas of your body inappropriate happiness difficulty falling asleep or staying asleep extreme ... increased appetite injection site pain or redness Some side effects can ...

  3. Pralatrexate Injection

    MedlinePlus

    ... you that you will need to receive a vitamin B12 injection no more than 10 weeks before your first ... tests to check your body's response to pralatrexate injection.Ask your ... such as vitamins, minerals, or other dietary supplements. You should bring ...

  4. Leucovorin Injection

    MedlinePlus

    ... lack of vitamin B12 or inability to absorb vitamin B12. Your doctor will not prescribe leucovorin injection to treat this type of anemia.tell your ... tests to check your body's response to leucovorin injection.It is ... such as vitamins, minerals, or other dietary supplements. You should bring ...

  5. Etanercept Injection

    MedlinePlus

    ... and colorless. The liquid may contain small white particles, but should not contain large or colored particles. Do not use a syringe or dosing pen ... liquid is cloudy or contains large or colored particles.The best place to inject etanercept injection is ...

  6. Short Durations of Static Stretching when Combined with Dynamic Stretching do not Impair Repeated Sprints and Agility

    PubMed Central

    Wong, Del P.; Chaouachi, Anis; Lau, Patrick W.C.; Behm, David G.

    2011-01-01

    This study aimed to compare the effect of different static stretching durations followed by dynamic stretching on repeated sprint ability (RSA) and change of direction (COD). Twenty-five participants performed the RSA and COD tests in a randomized order. After a 5 min aerobic warm up, participants performed one of the three static stretching protocols of 30 s, 60 s or 90 s total duration (3 stretches x 10 s, 20 s or 30 s). Three dynamic stretching exercises of 30 s duration were then performed (90 s total). Sit-and-reach flexibility tests were conducted before the aerobic warm up, after the combined static and dynamic stretching, and post- RSA/COD test. The duration of static stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit-and-reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001). However there were no significant differences in RSA and COD performance between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. Furthermore, the short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments. Key points The duration of combined static and dynamic stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit and reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001). No significant differences in RSA and COD between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. The short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments. PMID:24149890

  7. Musculoskeletal Injection

    PubMed Central

    Wittich, Christopher M.; Ficalora, Robert D.; Mason, Thomas G.; Beckman, Thomas J.

    2009-01-01

    Patients commonly present to primary care physicians with musculoskeletal symptoms. Clinicians certified in internal medicine must be knowledgeable about the diagnosis and management of musculoskeletal diseases, yet they often receive inadequate postgraduate training on this topic. The musculoskeletal problems most frequently encountered in our busy injection practice involve, in decreasing order, the knees, trochanteric bursae, and glenohumeral joints. This article reviews the clinical presentations of these problems. It also discusses musculoskeletal injections for these problems in terms of medications, indications, injection technique, and supporting evidence from the literature. Experience with joint injection and the pharmacological principles described in this article should allow primary care physicians to become comfortable and proficient with musculoskeletal injections. PMID:19720781

  8. Fledging success is a poor indicator of the effects of bird blow flies on ovenbird survival

    USGS Publications Warehouse

    Streby, Henry M.; Peterson, Sean M.; Kapfer, Paul M.

    2009-01-01

    Infestations of bird blow flies (Protocalliphora spp. and Trypocalliphora braueri) have various negative effects on the condition of nestling birds. In the absence of other stressors such as inclement weather, however, infestation alone rarely reduces fledging success. Previous studies have documented effects of blow flies on nestling condition and fledging success. Without information regarding fledgling survival, the full effect of blow-fly infestation remains unclear. To fully investigate the effect of blow-fly infestation on reproductive success of the Ovenbird (Seiurus aurocapilla), we monitored infested and non-infested nests and monitored fledglings from each by using radio telemetry. Blow flies did not affect birds during the nestling period, as brood size, mean nestling mass, fledging success, and time to fledging in infested and non-infested nests were no different. Fledgling survival and minimum distance traveled the first day after fledging, however, were significantly lower for infected fledglings than for those that were not infected. We conclude that the stress of the early fledgling period combined with recent or concurrent blow-fly infection increases mortality in young Oven-birds. Our results demonstrate the importance of including the post-fledging period in investigations of the effects of ectoparasitic infestations on birds.

  9. First Satellite-detected Perturbations of Outgoing Longwave Radiation Associated with Blowing Snow Events over Antarctica

    NASA Technical Reports Server (NTRS)

    Yang, Yuekui; Palm, Stephen P.; Marshak, Alexander; Wu, Dong L.; Yu, Hongbin; Fu, Qiang

    2014-01-01

    We present the first satellite-detected perturbations of the outgoing longwave radiation (OLR) associated with blowing snow events over the Antarctic ice sheet using data from Cloud-Aerosol Lidar with Orthogonal Polarization and Clouds and the Earth's Radiant Energy System. Significant cloud-free OLR differences are observed between the clear and blowing snow sky, with the sign andmagnitude depending on season and time of the day. During nighttime, OLRs are usually larger when blowing snow is present; the average difference in OLRs between without and with blowing snow over the East Antarctic Ice Sheet is about 5.2 W/m2 for the winter months of 2009. During daytime, in contrast, the OLR perturbation is usually smaller or even has the opposite sign. The observed seasonal variations and day-night differences in the OLR perturbation are consistent with theoretical calculations of the influence of blowing snow on OLR. Detailed atmospheric profiles are needed to quantify the radiative effect of blowing snow from the satellite observations.

  10. Two-dimensional axisymmetric magnetohydrodynamic analysis of blow-by in a coaxial plasma accelerator

    NASA Astrophysics Data System (ADS)

    Cassibry, J. T.; Thio, Y. C. F.; Wu, S. T.

    2006-05-01

    When the driving magnetic pressure profile is unbalanced by the plasma density profile in a coaxial plasma accelerator, a portion of the plasma and associated current sheet may "blow by" the remaining bulk of the plasma. The fast moving plasma creates a significant back electromotive force, draining energy otherwise available for acceleration. The onset of blow-by for an unmagnetized plasma of finite length in a straight coaxial plasma accelerator was studied by exploring systematically the effects of the initial density profile, driving current, plasma temperature, inductance gradient, and electrode radii scale size on the blow-by time. In order to avoid the onset of blow-by, the principal acceleration phase needs to be less than the characteristic blow-by time, which is a function of electrode geometry, plasma conditions, and circuit parameters. For an initially uniform density profile, the total impulse at blow-by time is proportional to the current, plasma mass, jet length, and reciprocal of the electrode radius ratio.

  11. Treatment of Orbital Roof Blow-Up Fracture Using a Superior Blepharoplasty Incision.

    PubMed

    Matsuzaki, Kyoichi; Enomoto, Sayaka; Aoki, Tomoko

    2015-06-01

    In orbital roof blow-up fractures, reduction can be achieved easily using an approach from the anterior cranial fossa but the procedure is highly invasive. In contrast, an orbital approach using a superior blepharoplasty incision is minimally invasive. However, if bone fragments are adhered to the dura mater, there is a risk of dura mater injury when fragments are moved for reduction. In blow-in fractures, reduction is performed by pushing the bone fragments against the anterior cranial fossa. In contrast, the procedure is difficult for blow-up fractures because bone fragments must be pulled out into the orbit through the anterior cranial fossa. Orbital blow-up fractures are often associated with intracranial injuries and frequently treated by an approach from the anterior cranial fossa. There has not yet been a report that discusses whether reduction of bone fragments should be performed in blow-up fracture without intracranial injury. In this report, we describe two cases of orbital roof blow-up fracture that did not require treatment for intracranial injury and that were treated using an orbital approach. The treatment involved only the release of orbital fat entrapped between bone fragments and did not involve reduction. The treatment outcomes were good in both cases. PMID:25836594

  12. Study on the conditions necessary for blowing snow to occur in which multiple meteorological elements are considered

    NASA Astrophysics Data System (ADS)

    Omiya, S.; Takechi, H.; Kokubu, T.; Harada, Y.; Matsuzawa, M.

    2015-12-01

    Elucidation of the conditions under which blowing snow occurs is important not only in mitigating snowstorm-related disasters but also in discussing the mass balance of water. The major factor for the occurrence of blowing snow is strong winds. However, the conditions that cause blowing snow are complicated, because temperature, the condition of the snow surface, and the presence or absence of falling snow affect blowing snow occurrence. We created a formula for determining the conditions under which blowing snow will occur, based on multiple meteorological elements. In this presentation, we report the results of analysis on the occurrence conditions of blowing snow without concurrent falling snow. The observation data used in the analysis were obtained in Hokkaido, northern Japan, from December 2012 to April 2013. The observed items were air temperature, wind velocity, intensity of solar radiation, snow depth and the mass flux of blowing snow particles. In addition to the above, videos were taken to determine the presence of blowing snow. After the blowing snow events were extracted, each meteorological element was compared with the frequency of blowing snow occurrence. The analysis found that the frequency tended to be low when 12 or more hours had passed after a snowfall event or when the maximum air temperature exceeded 2 °C. It is thought that the snow particles sinter together and the surface of the snow pack hardens, and that such sintering makes it difficult for the particles fly off from the snow surface. It was shown that the frequency of blowing snow occurrence is high when large amounts of fresh snow are on the ground. Based on the above examinations, a formula for determining the occurrence of blowing snow was created using the discriminate analysis method. An accuracy verification test found the formula to have a hit ratio of 92.3%. The verification test showed the formula to be useful in determining the occurrence of blowing snow.

  13. Secondary structure of double-stranded DNA under stretching: Elucidation of the stretched form

    NASA Astrophysics Data System (ADS)

    Maaloum, M.; Beker, A.-F.; Muller, P.

    2011-03-01

    Almost two decades ago, measurements of force versus extension on isolated double-stranded DNA molecules revealed a force plateau. This unusual stretching phenomenon in DNA suggests that the long molecules may be extended from the usual B form into a new conformation. Different models have been proposed to describe the nature of DNA in its stretched form, S-DNA. Using atomic force microscopy combined with a molecular combing method, we identified the structure of λ-phage DNA for different stretching values. We provide strong evidence for the existence of a first-order transition between B form and S form. Beyond a certain extension of the natural length, DNA molecules adopt a new double-helix conformation characterized by a diameter of 1.2 nm and a helical pitch of 18 nm.

  14. Secondary structure of double-stranded DNA under stretching: Elucidation of the stretched form

    SciTech Connect

    Maaloum, M.; Muller, P.; Beker, A-F.

    2011-03-15

    Almost two decades ago, measurements of force versus extension on isolated double-stranded DNA molecules revealed a force plateau. This unusual stretching phenomenon in DNA suggests that the long molecules may be extended from the usual B form into a new conformation. Different models have been proposed to describe the nature of DNA in its stretched form, S-DNA. Using atomic force microscopy combined with a molecular combing method, we identified the structure of {lambda}-phage DNA for different stretching values. We provide strong evidence for the existence of a first-order transition between B form and S form. Beyond a certain extension of the natural length, DNA molecules adopt a new double-helix conformation characterized by a diameter of 1.2 nm and a helical pitch of18 nm.

  15. Effects of cervical self-stretching on slow vital capacity

    PubMed Central

    Han, Dongwook; Yoon, Nayoon; Jeong, Yeongran; Ha, Misook; Nam, Kunwoo

    2015-01-01

    [Purpose] This study investigated the effects of self-stretching of cervical muscles, because the accessory inspiratory muscle is considered to improve pulmonary function. [Subjects] The subjects were 30 healthy university students 19–21 years old who did not have any lung disease, respiratory dysfunction, cervical injury, or any problems upon cervical stretching. [Methods] Spirometry was used as a pulmonary function test to measure the slow vital capacity before and after stretching. The slow vital capacity of the experimental group was measured before and after cervical self-stretching. Meanwhile, the slow vital capacity of the control group, which did not perform stretching, was also measured before and after the intervention. [Results] The expiratory vital capacity, inspiratory reserve volume, and expiratory reserve volume of the experimental group increased significantly after the cervical self-stretching. [Conclusion] Self-stretching of the cervical muscle (i.e., the inspiratory accessory muscle) improves slow vital capacity. PMID:26311984

  16. Acute effects of dynamic stretching, static stretching, and light aerobic activity on muscular performance in women.

    PubMed

    Curry, Brad S; Chengkalath, Devendra; Crouch, Gordon J; Romance, Michelle; Manns, Patricia J

    2009-09-01

    The purpose of this study was to compare three warm-up protocols--static stretching, dynamic stretching, and light aerobic activity--on selected measures of range of motion and power in untrained females and to investigate the sustained effects at 5 and 30 minutes after warm-up. A total of 24 healthy females (ages 23-29 years) attended one familiarization session and three test sessions on nonconsecutive days within 2 weeks. A within-subject design protocol with the testing investigators blinded to the subjects' warm-up was followed. Each session started with 5 minutes of light aerobic cycling followed by pretest baseline measures. Another 5 minutes of light aerobic cycling was completed and followed by one of the three randomly selected warm-up interventions (static stretching, dynamic stretching, or light aerobic activity). The following posttest outcome measures were collected 5 and 30 minutes following the intervention: modified Thomas test, countermovement jump, and isometric time to peak force knee extension measured by dynamometer. Analysis of the data revealed significant time effects on range of motion and countermovement jump changes. No significant differences (p > 0.05) were found between the warm-up conditions on any of the variables. The variation in responses to warm-up conditions emphasizes the unique nature of individual reactions to different warm-ups; however, there was a tendency for warm-ups with an active component to have beneficial effects. The data suggests dynamic stretching has greater applicability to enhance performance on power outcomes compared to static stretching. PMID:19675479

  17. Fuel injection

    SciTech Connect

    Iiyoshi, A.; Vogoshi, S.

    1983-12-01

    The Plasma Physics Laboratory and the Dept. of Electrical Engineering report on three types of pellet injectors which have different applications: injection of a pellet into a magnetic bottle for magnetic confinement; injection of a pellet into a vacuum chamber for an inertial confinement experiment; and injection of a pellet into a magnetic bottle where the pellet is ionized by high-power laser irradiation for target plasma production. The requirements of pellet injectors are summarized in a table. Theoretical studies on pellet ablation in hot plasma and ablated particle diffusion are underway.

  18. Uni-Directional Cell Stretching Device

    NASA Technical Reports Server (NTRS)

    Feeback, Daniel L. (Inventor); Clarke, Mark S. F. (Inventor)

    2000-01-01

    The present invention relates to an apparatus and method for applying various degrees of linear, mechanical loads on mammalian tissues, and in particular, for effecting linear stretching of tissue and simulating changes in hydrostatic pressures encountered during tissue contraction in vivo. The apparatus is useful for the study of mechanical loading in human tissue, and specifically, for permitting the evaluation of the effects of mechanical loading of skeletal or cardiac tissue and of the effects of removal of mechanical loading due to inactivity or the like, and the subsequent reapplication of load to these tissues.

  19. To Stretch and Search for Better Ways

    NASA Astrophysics Data System (ADS)

    Moore, John W.

    2000-06-01

    There's a lot to do to get each issue of this Journal ready for publication, and there's a lot that can go awry during that process. We the editorial staff do our utmost to make certain that each issue is the best it can possibly be, but, of necessity, a lot of our effort is focused on solving problems, correcting errors, and avoiding pitfalls. It is not surprising that we sometimes lose sight of the bigger picture--all of the things that came out as well as or better than we hoped they would. Therefore it gives us great pleasure when a reader applauds (and thereby rewards) our efforts. One such communication inspired this editorial.

    I have appreciated the extra effort put forward by the staff to make the Journal really come alive. The high quality of the Journal serves as an incentive to chemical educators to stretch and search for better ways to inspire our students.
    I fervently hope that we do encourage you "to stretch and search for better ways", not only to inspire students but in everything you do. Stretching and searching for better ways is what life, science, chemistry, and teaching are all about, and it is a wonderfully stimulating and exciting way to approach anything and everything. Sometimes, though, one's ability to stretch is akin to that of a rubber band exposed too long to sunlight. Change becomes a threat or a burden instead of an opportunity. This often happens in one area but not others, as in the case of someone doing original research but whose lecture notes are yellow with age, or someone who experiments with new teaching approaches but neglects the latest chemical discoveries. Whatever its manifestation, failure to stretch and search for better ways is a great loss, both for the individual directly involved and for others. Fortunately there are many who continually stretch and search, often in conjunction with JCE. For example, some time ago the Chair of the Board of Publication, Jerry Bell, challenged Journal

  20. Stretching of proteins in a uniform flow

    NASA Astrophysics Data System (ADS)

    Szymczak, P.; Cieplak, Marek

    2006-10-01

    Stretching of a protein by a fluid flow is compared to that in a force-clamp apparatus. The comparison is made within a simple topology-based dynamical model of a protein in which the effects of the flow are implemented using Langevin dynamics. We demonstrate that unfolding induced by a uniform flow shows a richer behavior than that in the force clamp. The dynamics of unfolding is found to depend strongly on the selection of the amino acid, usually one of the termini, which is anchored. These features offer potentially wider diagnostic tools to investigate structure of proteins compared to experiments based on the atomic force microscopy.

  1. Tensioning device for a stretched membrane collector

    DOEpatents

    Murphy, L.M.

    1984-01-01

    Disclosed is a solar concentrating collector comprising an elestic membrane member for concentrating sunlight, a frame for holding the membrane member in plane and in tension, and a tensioning means for varying the tension of the membrane member. The tensioning means is disposed at the frame and is adapted to releasably attach the membrane member thereto. The tensioning means is also adapted to uniformly and symmetrically subject the membrane member to stretching forces such that membrane stresses produced thereby are distributed uniformly over a thickness of the membrane member and reciprocal twisting moments are substantially prevented from acting about said frame.

  2. Tensioning device for a stretched membrane collector

    DOEpatents

    Murphy, Lawrence M.

    1984-01-01

    Disclosed is a solar concentrating collector comprising an elastic membrane member for concentrating sunlight, a frame for holding the membrane member in plane and in tension, and a tensioning means for varying the tension of the membrane member. The tensioning means is disposed at the frame and is adapted to releasably attach the membrane member thereto. The tensioning means is also adapted to uniformly and symmetrically subject the membrane member to stretching forces such that membrane stresses produced thereby are distributed uniformly over a thickness of the membrane member and reciprocal twisting moments are substantially prevented from acting about said frame.

  3. Understanding the bacterial communities of hard cheese with blowing defect.

    PubMed

    Bassi, Daniela; Puglisi, Edoardo; Cocconcelli, Pier Sandro

    2015-12-01

    The environment of hard cheese encourages bacterial synergies and competitions along the ripening process, which might lead in defects such as clostridial blowing. In this study, Denaturing Gradient Gel Electrophoresis (DGGE), a quantitative Clostridium tyrobutyricum PCR and next-generation Illumina-based sequencing of 16S rRNA gene were applied to study 83 Grana Padano spoiled samples. The aim was to investigate the community of clostridia involved in spoilage, the ecological relationships with the other members of the cheese microbiota, and the effect of lysozyme. Three main genera were dominant in the analysed cheeses, Lactobacillus, Streptococcus and Clostridium, and the assignment at the species level was of 94.3% of 4,477,326 high quality sequences. C. tyrobutyricum and C. butyricum were the most prevalent clostridia. Hierarchical clustering based on the abundance of bacterial genera, revealed three main clusters: one characterized by the highest proportion of Clostridium, a second where Lactobacillus was predominant and the last, dominated by Streptococcus thermophilus. Ecological relationships among species were found: cheeses characterized by an high abundance of S. thermophilus and L. rhamnosus were spoiled by C. tyrobutyricum while, when L. delbrueckii was the most abundant Lactobacillus, C. butyricum was the dominant spoiling species. Lysozyme also shaped the bacterial community, reducing C. tyrobutyricum in favour of C. butyricum. Moreover, this preservative increased the proportion of L. delbrueckii and obligate heterofermentative lactobacilli and lowered L. helveticus and non-starter species, such as L. rhamnosus and L. casei. PMID:26338123

  4. Airborne contamination during blow-fill-seal pharmaceutical production.

    PubMed

    Whyte, W; Matheis, W; Dean-Netcher, M; Edwards, A

    1998-01-01

    The routes of airborne contamination, during Blow-Fill-Seal (BFS) production, were studied using tracer gas, particles and bacteria. The prevention of airborne contamination, by the air shower at the point of fill, was effective (> 99.2% efficient). However, microbe-carrying particles could gain access, by deposition or air exchange, when the containers were cut open and before they shuttled under the protection of the air shower. The use of SF6 tracer gas demonstrated that when the air shower was not on, 50% of the air within the containers came from the area round the machine. When the air shower was switched on, only about 5% of the air came from the surroundings. Airborne microbial contamination of containers is in proportion to: the number of airborne microbes around the machine, the time the container is open, the neck area and the amount of air left within the container. The likely microbial contamination rate can be calculated from a model incorporating these variables. Microbial contamination of containers during BFS manufacturing is normally very low, but by increasing the naturally occurring bacteria in the air of the production rooms by about 100-fold, it was possible to verify the accuracy of this model. The contamination model agrees well with the observation that microbial contamination levels of between 1 in 10(5) and in 10(7) will be found when small containers (< 10 ml) are filled in conventionally ventilated rooms. To achieve similar contamination rates when filling of larger bottles, it is likely that unidirectional flow, or barrier technology will be required. PMID:9691671

  5. Certolizumab Injection

    MedlinePlus

    ... has not improved when treated with other medications, rheumatoid arthritis (a condition in which the body attacks its ... continues. When certolizumab injection is used to treat rheumatoid arthritis, it is usually given every other week and ...

  6. Ramucirumab Injection

    MedlinePlus

    ... dose of ramucirumab injection. Tell your doctor or nurse if you experience any of the following while you receive ramucirumab: uncontrollable shaking of a part of the body; back pain or spasms; chest pain and tightness; chills; flushing; ...

  7. Topotecan Injection

    MedlinePlus

    ... organs where eggs are formed) and small cell lung cancer (a type of cancer that begins in the ... topotecan injection is used to treat ovarian or lung cancer, it is usually given once a day for ...

  8. Colistimethate Injection

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  9. Mitoxantrone Injection

    MedlinePlus

    ... medications to relieve pain in people with advanced prostate cancer who did not respond to other medications. Mitoxantrone ... doses). When mitoxantrone injection is used to treat prostate cancer, it is usually given once every 21 days. ...

  10. Palivizumab Injection

    MedlinePlus

    ... this medicine each month during RSV season. Your health care provider will let you know when the monthly injections are no longer needed.Your child's health care provider (doctor, nurse, or pharmacist) may measure ...

  11. Terbutaline Injection

    MedlinePlus

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  12. Leuprolide Injection

    MedlinePlus

    ... of the body and causes pain, heavy or irregular menstruation [periods], and other symptoms). Leuprolide injection (Lupron ... mention any of the following: certain medications for irregular heartbeat such as amiodarone (Cordarone), disopyramide (Norpace), procainamide ( ...

  13. Sumatriptan Injection

    MedlinePlus

    ... accompanied by nausea and sensitivity to sound and light). Sumatriptan injection is also used to treat the ... children. Store it at room temperature, away from light, excess heat, and moisture (not in the bathroom). ...

  14. Insulin Injection

    MedlinePlus

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  15. Fondaparinux Injection

    MedlinePlus

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  16. Daclizumab Injection

    MedlinePlus

    ... course of disease where symptoms flare up from time to time) of multiple sclerosis (MS; a disease in which ... injections. Before you use daclizumab yourself the first time, read the written instructions that come with it. ...

  17. Haloperidol Injection

    MedlinePlus

    ... emotions). Haloperidol injection is also used to control motor tics (uncontrollable need to repeat certain body movements) ... people who have Tourette's disorder (condition characterized by motor or verbal tics). Haloperidol is in a class ...

  18. Certolizumab Injection

    MedlinePlus

    ... causes pain, swelling, and damage) including the following: Crohn's disease (a condition in which the body attacks the ... home. When certolizumab injection is used to treat Crohn's disease, it is usually given every two weeks for ...

  19. Natalizumab Injection

    MedlinePlus

    ... prevent episodes of symptoms in people who have Crohn's disease (a condition in which the body attacks the ... If you are receiving natalizumab injection to treat Crohn's disease, your symptoms should improve during the first few ...

  20. Daptomycin Injection

    MedlinePlus

    ... blood infections or serious skin infections caused by bacteria. Daptomycin injection is in a class of medications called cyclic lipopeptide antibiotics. It works by killing bacteria. Antibiotics will not work for treating colds, flu, ...

  1. Ciprofloxacin Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria. Ciprofloxacin injection is also used to prevent or ... of antibiotics called fluoroquinolones. It works by killing bacteria that cause infections. Antibiotics will not work for ...

  2. Gentamicin Injection

    MedlinePlus

    ... treat certain serious infections that are caused by bacteria such as meningitis (infection of the membranes that ... medications called aminoglycoside antibiotics. It works by killing bacteria.Antibiotics such as gentamicin injection will not work ...

  3. Ertapenem Injection

    MedlinePlus

    ... abdominal (stomach area) infections, that are caused by bacteria. It is also used for the prevention of ... medications called carbapenem antibiotics. It works by killing bacteria.Antibiotics such as ertapenem injection will not work ...

  4. Cefepime Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria including pneumonia, and skin, urinary tract, and kidney ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefepime injection will not work ...

  5. Ceftriaxone Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria such as gonorrhea (a sexually transmitted disease), pelvic ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as ceftriaxone injection will not work ...

  6. Moxifloxacin Injection

    MedlinePlus

    ... skin, and abdominal (stomach area) infections caused by bacteria. Moxifloxacin injection is in a class of antibiotics called fluoroquinolones. It works by killing the bacteria that cause infections. Antibiotics will not work against ...

  7. Ceftaroline Injection

    MedlinePlus

    ... infections and pneumonia (lung infection) caused by certain bacteria. Ceftaroline is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as ceftaroline injection will not work ...

  8. Tobramycin Injection

    MedlinePlus

    ... treat certain serious infections that are caused by bacteria such as meningitis (infection of the membranes that ... medications called aminoglycoside antibiotics. It works by killing bacteria.Antibiotics such as tobramycin injection will not work ...

  9. Cefazolin Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria including skin, bone, joint, genital, blood, heart valve, ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefazolin injection will not work ...

  10. Cefotaxime Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria including pneumonia and other lower respiratory tract (lung) ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefotaxime injection will not work ...

  11. Amikacin Injection

    MedlinePlus

    ... treat certain serious infections that are caused by bacteria such as meningitis (infection of the membranes that ... medications called aminoglycoside antibiotics. It works by killing bacteria.Antibiotics such as amikacin injection will not work ...

  12. Ampicillin Injection

    MedlinePlus

    ... to treat certain infections that are caused by bacteria such as meningitis (infection of the membranes that ... of medications called penicillins. It works by killing bacteria.Antibiotics such as ampicillin injection will not work ...

  13. Cefuroxime Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria including pneumonia and other lower respiratory tract (lung) ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefuroxime injection will not work ...

  14. Vancomycin Injection

    MedlinePlus

    ... medications called glycopeptide antibiotics. It works by killing bacteria that cause infections.Antibiotics such as vancomycin injection ... infection may not be completely treated and the bacteria may become resistant to antibiotics.

  15. Ceftazidime Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria including pneumonia and other lower respiratory tract (lung) ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as ceftazidime injection will not work ...

  16. Telavancin Injection

    MedlinePlus

    ... serious skin infections caused by certain types of bacteria. Telavancin injection is in a class of medications ... antibiotics. It works by stopping the growth of bacteria. Antibiotics will not work for colds, flu, or ...

  17. Teduglutide Injection

    MedlinePlus

    ... injection, prefilled syringes containing diluent (liquid to be mixed with teduglutide powder), needles to attach to the diluent syringe, dosing syringes with needles attached, and alcohol swab pads. Throw away needles, syringes, and vials ...

  18. Cefoxitin Injection

    MedlinePlus

    ... is in a class of medications called cephamycin antibiotics. It works by killing bacteria.Antibiotics such as cefoxitin injection will not work for colds, flu, or other viral infections. Taking antibiotics when they are not needed increases your risk ...

  19. Nafcillin Injection

    MedlinePlus

    ... medications called penicillins. It works by killing bacteria.Antibiotics such as nafcillin injection will not work for colds, flu, or other viral infections. Taking antibiotics when they are not needed increases your risk ...

  20. Cefepime Injection

    MedlinePlus

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefepime injection will not work for colds, flu, or other viral infections. Using antibiotics when they are not needed increases your risk ...

  1. Oxacillin Injection

    MedlinePlus

    ... medications called penicillins. It works by killing bacteria.Antibiotics such as oxacillin injection will not work for colds, flu, or other viral infections. Taking antibiotics when they are not needed increases your risk ...

  2. Dexamethasone Injection

    MedlinePlus

    ... severe allergic reactions. It is used in the management of certain types of edema (fluid retention and ... needed for normal body functioning) and in the management of certain types of shock. Dexamethasone injection is ...

  3. Pembrolizumab Injection

    MedlinePlus

    ... treat a certain type of non-small-cell lung cancer that has spread to nearby tissues or to ... successfully with other medications for non-small-cell lung cancer. Pembrolizumab injection is in a class of medications ...

  4. Ibandronate Injection

    MedlinePlus

    ... Ibandronate is in a class of medications called bisphosphonates. It works by preventing bone breakdown and increasing ... while receiving this medication.Being treated with a bisphosphonate medication such as ibandronate injection for osteoporosis may ...

  5. Omalizumab Injection

    MedlinePlus

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  6. Necitumumab Injection

    MedlinePlus

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  7. Dolasetron Injection

    MedlinePlus

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  8. Topotecan Injection

    MedlinePlus

    ... also used together with other medications to treat cervical cancer (cancer that begins in the opening of the ... days. When topotecan injection is used to treat cervical cancer, it is usually given once a day for ...

  9. Ertapenem Injection

    MedlinePlus

    Ertapenem injection is used to treat certain serious infections, including pneumonia and urinary tract, skin, diabetic foot, ... for the prevention of infections following colorectal surgery. Ertapenem is in a class of medications called carbapenem ...

  10. Octreotide Injection

    MedlinePlus

    ... immediate-release injection is also used to control diarrhea and flushing caused by carcinoid tumors (slow-growing ... symptoms are severe or do not go away: diarrhea constipation pale, bulky, foul-smelling stools constantly feeling ...

  11. Infliximab Injection

    MedlinePlus

    ... injection may cause serious allergic reactions during an infusion and for 2 hours afterward. A doctor or ... the following symptoms during or shortly after your infusion: hives; rash; itching; swelling of the face, eyes, ...

  12. Vedolizumab Injection

    MedlinePlus

    ... injection may cause serious allergic reactions during an infusion and for several hours afterward. A doctor or ... of the following symptoms during or after your infusion: rash; itching; swelling of the face, eyes, mouth, ...

  13. Panitumumab Injection

    MedlinePlus

    ... as a solution (liquid) to be given by infusion (injected into a vein). It is usually given ... doctor or nurse in a doctor's office or infusion center. Panitumumab is usually given once every 2 ...

  14. Tositumomab Injection

    MedlinePlus

    ... is in a class of medications called monoclonal antibodies with radioisotopes. It works by attaching to cancer ... you receive tositumomab injection, your body may develop antibodies (substances in the blood that help the immune ...

  15. Ibritumomab Injection

    MedlinePlus

    ... is in a class of medications called monoclonal antibodies with radioisotopes. It works by attaching to cancer ... you receive ibritumomab injection, your body may develop antibodies (substances in the blood that help the immune ...

  16. Temozolomide Injection

    MedlinePlus

    Temozolomide is used to treat certain types of brain tumors. Temozolomide is in a class of medications called ... injected once a day. For some types of brain tumors, temozolomide is given daily for 42 to 49 ...

  17. Tigecycline Injection

    MedlinePlus

    ... to treat certain serious infections including community acquired pneumonia (a lung infection that developed in a person ... Tigecycline injection should not be used to treat pneumonia that developed in people who were in a ...

  18. Acetaminophen Injection

    MedlinePlus

    ... injection is also used in combination with opioid (narcotic) medications to relieve moderate to severe pain. Acetaminophen is in a class of medications called analgesics (pain relievers) and antipyretics (fever reducers). It works by changing ...

  19. Dexrazoxane Injection

    MedlinePlus

    ... certain side effects that may be caused by chemotherapy medications. Dexrazoxane injection (Zinecard) is used to prevent ... tissues that may be caused when an anthracycline chemotherapy medication such as daunorubicin (Daunoxome, Cerubidine), doxorubicin (Doxil), ...

  20. Denosumab Injection

    MedlinePlus

    ... menstrual periods), who have an increased risk for fractures (broken bones) or who cannot take or did ... receiving certain treatments that increase their risk for fractures. Denosumab injection (Xgeva) is used to reduce fractures ...

  1. Mitoxantrone Injection

    MedlinePlus

    ... of disability in patients with certain forms of multiple sclerosis (MS). Mitoxantrone injection is also used together with steroid ... a class of medications called anthracenediones. Mitoxantrone treats MS by stopping certain cells of the immune system ...

  2. Dexrazoxane Injection

    MedlinePlus

    ... and pharmacist if you are allergic to dexrazoxane injection or any other medications.tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking ...

  3. Oritavancin Injection

    MedlinePlus

    ... for at least 5 days after receiving oritavancin injection.tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking ...

  4. Ferumoxytol Injection

    MedlinePlus

    Ferumoxytol injection is used to treat iron-deficiency anemia (a lower than normal number of red blood cells due to too little iron) in adults with chronic kidney disease (damage to the kidneys which may worsen over ...

  5. Exenatide Injection

    MedlinePlus

    ... month. Exenatide extended-release solution is injected once weekly at any time of day without regard to ... you remember it and then continue your regular weekly schedule. However, if there are less than 3 ...

  6. Fluconazole Injection

    MedlinePlus

    ... injection is used to treat fungal infections, including yeast infections of the mouth, throat, esophagus (tube leading from ... by fungus. Fluconazole is also used to prevent yeast infections in patients who are likely to become infected ...

  7. Mipomersen Injection

    MedlinePlus

    Mipomersen injection is used to decrease levels of cholesterol and other fatty substances in the blood in people who have homozygous familial hypercholesterolemia (HoFH; a rare inherited condition that ...

  8. Cefuroxime Injection

    MedlinePlus

    ... pneumonia and other lower respiratory tract (lung) infections; meningitis (infection of the membranes that surround the brain ... hearing loss, if you are being treated for meningitis Cefuroxime injection may cause other side effects. Call ...

  9. Busulfan Injection

    MedlinePlus

    ... cancer cells in preparation for a bone marrow transplant. Busulfan is in a class of medications called ... a total of 16 doses) before bone marrow transplant.Busulfan injection may cause seizures during therapy with ...

  10. Methylnaltrexone Injection

    MedlinePlus

    ... injection is used to treat constipation caused by opioid (narcotic) pain medications in patients with advanced illnesses ... a class of medications called peripherally acting mu-opioid receptor antagonists. It works by protecting the bowel ...

  11. Methylprednisolone Injection

    MedlinePlus

    ... treatment.You may receive methylprednisolone injection in a hospital or medical facility, or you may be given ... doctor or if you are admitted to a hospital. It is also important information to carry with ...

  12. Ampicillin Injection

    MedlinePlus

    ... have.You may receive ampicillin injection in a hospital or you may administer the medication at home. ... doctor or if you are admitted to a hospital. It is also important information to carry with ...

  13. Romidepsin Injection

    MedlinePlus

    ... bleeding fever, cough, flu-like symptoms, muscle aches, burning on urination, worsening skin problems, and other signs of infection rash blistering or peeling skin Romidepsin injection may cause other side effects. Call your doctor if you have any unusual ...

  14. Ranitidine Injection

    MedlinePlus

    ... the pancreas and small intestine that caused increased production of stomach acid). Ranitidine injection is in a ... your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response ...

  15. Ganciclovir Injection

    MedlinePlus

    ... injection is for intravenous (into a vein) use only. Giving ganciclovir through intramuscular (into a muscle) or ... the storage of ganciclovir solution. Store your medication only as directed. Make sure you understand what you ...

  16. Teduglutide Injection

    MedlinePlus

    ... syndrome in people who need additional nutrition or fluids from intravenous (IV) therapy. Teduglutide injection is in ... analogs. It works by improving the absorption of fluids and nutrients in the intestines.

  17. Olanzapine Injection

    MedlinePlus

    Olanzapine extended-release injection is used to treat schizophrenia (a mental illness that causes disturbed or unusual ... treat episodes of agitation in people who have schizophrenia or in people who have bipolar I disorder ( ...

  18. Risperidone Injection

    MedlinePlus

    ... release (long-acting) injection is used to treat schizophrenia (a mental illness that causes disturbed or unusual ... do not already have diabetes. If you have schizophrenia, you are more likely to develop diabetes than ...

  19. Aripiprazole Injection

    MedlinePlus

    ... injections (Abilify Maintena, Aristada) are used to treat schizophrenia (a mental illness that causes disturbed or unusual ... treat episodes of agitation in people who have schizophrenia or in people who have bipolar I disorder ( ...

  20. Secukinumab Injection

    MedlinePlus

    ... to see if you need to receive any vaccinations. It is important to have all vaccines appropriate ... treatment with secukinumab injection. Do not have any vaccinations during your treatment without talking to your doctor. ...

  1. Tesamorelin Injection

    MedlinePlus

    ... fat in the stomach area in adults with human immunodeficiency virus (HIV) who have lipodystrophy (increased body ... injection is in a class of medications called human growth hormone-releasing factor (GRF) analogs. It works ...

  2. Naloxone Injection

    MedlinePlus

    ... emergency medical treatment to reverse the life-threatening effects of a known or suspected opiate (narcotic) overdose. ... is also used after surgery to reverse the effects of opiates given during surgery. Naloxone injection is ...

  3. Methotrexate Injection

    MedlinePlus

    ... Methotrexate injection is also used to treat severe psoriasis (a skin disease in which red, scaly patches ... slowing the growth of cancer cells. Methotrexate treats psoriasis by slowing the growth of skin cells to ...

  4. Sumatriptan Injection

    MedlinePlus

    ... sometimes are accompanied by nausea and sensitivity to sound and light). Sumatriptan injection is also used to ... stomach pain sudden weight loss paleness or blue color of the fingers and toes shortness of breath ...

  5. Denosumab Injection

    MedlinePlus

    ... injection is in a class of medications called RANK ligand inhibitors. It works by decreasing bone breakdown ... medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. ...

  6. Omacetaxine Injection

    MedlinePlus

    ... for CML and can no longer benefit from these medications or cannot take these medications due to side effects. Omacetaxine injection is ... side effects. Tell your doctor if any of these symptoms are severe or do not go away: ...

  7. Basiliximab Injection

    MedlinePlus

    ... is used with other medications to prevent immediate transplant rejection (attack of the transplanted organ by the immune system of the person receiving the organ) in people who are receiving kidney transplants. Basiliximab injection is in a class of medications ...

  8. Metoclopramide Injection

    MedlinePlus

    ... is used to relieve symptoms caused by slow stomach emptying in people who have diabetes. These symptoms include ... When metoclopramide injection is used to treat slowed stomach emptying due to diabetes, it may be given up ...

  9. Study on Stretching Methods of Biaxially Stretched Co-polyester Film with Has Uniaxially Heat Shrinkage Properties

    NASA Astrophysics Data System (ADS)

    Haruta, Masayuki; Mukouyama, Yukinobu; Tabota, Norimi; Ito, Katsuya; Nonomura, Chisato

    Heat shrinkable film made of stretched film is widely used for decorative labels by attaching on PET bottles with heat shrinkage by steam or dry heating. Trouble cancellation in the installation process of the PET bottle is necessary. The purpose of this study is development of uniaxially heat shrinkable co-polyester film that has strength both in the machine direction (MD) and transverse direction (TD). The film production was performed using sequential biaxial stretched process that combined roll stretching with TD stretching. Cast film was processed in the order of TD stretching-Anneal 1-MD stretching-Anneal 2. As a result, the heat shrinkable film that shrunk only in MD got high tensile strength both in MD and TD. The anneal 1 temperature over Tg (Glass transition temperature) of material resin was needed to obtain the heat shrinkable film shrunk in MD after TD stretching.

  10. Intrathymic Injection.

    PubMed

    Manna, Sugata; Bhandoola, Avinash

    2016-01-01

    Intrathymic injection is used in several T cell-associated immunological studies to deliver cells or other substances directly into the thymus. Here, we describe the intrathymic injection procedure involving surgical incision of the mouse with or without a thoracotomy. Though this procedure can result in poor recovery, postsurgical complications, and distress to the animal, it is actually a simple procedure that can be carried out relatively easily and quickly with experience. PMID:26294410

  11. Dense Plasma Injection Experiment at MCX

    NASA Astrophysics Data System (ADS)

    Uzun-Kaymak, I.; Messer, S.; Bomgardner, R.; Case, A.; Clary, R.; Ellis, R.; Elton, R.; Hassam, A.; Teodorescu, C.; Witherspoon, D.; Young, W.

    2009-09-01

    We present preliminary results of the High Density Plasma Injection Experiment at the Maryland Centrifugal Experiment (MCX). HyperV Technologies Corp. has designed, built, and installed a prototype coaxial gun to drive rotation in MCX. This gun has been designed to avoid the blow-by instability via a combination of electrode shaping and a tailored plasma armature. An array of diagnostics indicates the gun is capable of plasma jets with a mass of 160 μg at 70 km/s with an average plasma density above 1015 cm-3. Preliminary measurements are underway at MCX to understand the penetration of the plasma jet through the MCX magnetic field and the momentum transfer from the jet to the MCX plasma. Data will be presented for a wide range of MCX field parameters, and the prospects for future injection experiments will be evaluated.

  12. Computational analysis of forebody tangential slot blowing on the high alpha research vehicle

    NASA Technical Reports Server (NTRS)

    Gee, Ken

    1995-01-01

    A numerical analysis of forebody tangential slot blowing as a means of generating side force and yawing moment is conducted using an aircraft geometry. The Reynolds-averaged, thin-layer, Navier-Stokes equations are solved using a partially flux-split, approximately-factored algorithm. An algebraic turbulence model is used to determine the turbulent eddy viscosity values. Solutions are obtained using both patched and overset grid systems. In the patched grid model, and actuator plane is used to introduce jet variables into the flow field. The overset grid model is used to model the physical slot geometry and facilitate modeling of the full aircraft configuration. A slot optimization study indicates that a short slot located close to the nose of the aircraft provided the most side force and yawing moment per unit blowing coefficient. Comparison of computed surface pressure with that obtained in full-scale wind tunnel tests produce good agreement, indicating the numerical method and grid system used in the study are valid. Full aircraft computations resolve the changes in vortex burst point due to blowing. A time-accurate full-aircraft solution shows the effect of blowing on the changes in the frequency of the aerodynamic loads over the vertical tails. A study of the effects of freestream Mach number and various jet parameters indicates blowing remains effective through the transonic Mach range. An investigation of the force onset time lag associated with forebody blowing shows the lag to be minimal. The knowledge obtained in this study may be applied to the design of a forebody tangential slot blowing system for use on flight aircraft.

  13. Filament-stretching rheometry of complex fluids

    NASA Astrophysics Data System (ADS)

    McKinley, Gareth H.; Sridhar, Tamarapu

    Filament-stretching rheometers are devices for measuring the extensional viscosity of moderately viscous non-Newtonian fluids such as polymer solutions. In these devices, a cylindrical liquid bridge is initially formed between two circular end-plates. The plates are then moved apart in a prescribed manner such that the fluid sample is subjected to a strong extensional deformation. Asymptotic analysis and numerical computation show that the resulting kinematics closely approximate those of an ideal homogeneous uniaxial elongation. The evolution in the tensile stress (measured mechanically) and the molecular conformation (measured optically) can be followed as functions of the rate of stretching and the total strain imposed. The resulting rheological measurements are a sensitive discriminant of molecularly based constitutive equations proposed for complex fluids. The dynamical response of the elongating filament is also coupled to the extensional rheology of the polymeric test fluid, and this can lead to complex viscoelastic-flow instabilities such as filament necking and rupture or elastic peeling from the rigid end-plates.

  14. Characteristic infrared intensities of carbonyl stretching vibrations.

    PubMed

    Richter, Wagner E; Silva, Arnaldo F; Vidal, Luciano N; Bruns, Roy E

    2016-07-14

    The experimental infrared fundamental intensities of gas phase carbonyl compounds obtained by the integration of spectral bands in the Pacific Northwest National Laboratory (PNNL) spectral database are in good agreement with the intensities reported by other laboratories having a root mean square error of 27 km mol(-1) or about 13% of the average intensity value. The Quantum Theory of Atoms in Molecules/Charge-Charge Transfer-Counterpolarization (QTAIM/CCTCP) model indicates that the large intensity variation from 61.7 to 415.4 km mol(-1) is largely due to static atomic charge contributions, whereas charge transfer and counterpolarization effects essentially cancel one another leaving only a small net effect. The Characteristic Substituent Shift Model estimates the atomic charge contributions to the carbonyl stretching intensities within 30 km mol(-1) or 10% of the average contribution. However, owing to the size of the 2 × C × CTCP interaction contribution, the total intensities cannot be estimated with this degree of accuracy. The dynamic intensity contributions of the carbon and oxygen atoms account for almost all of the total stretching intensities. These contributions vary over large ranges with the dynamic contributions of carbon being about twice the size of the oxygen ones for a large majority of carbonyls. Although the carbon monoxide molecule has an almost null dipole moment contrary to the very polar bond of the characteristic carbonyl group, its QTAIM/CCTCP model is very similar to those found for the carbonyl compounds. PMID:27306140

  15. Curved Piezoelectric Actuators for Stretching Optical Fibers

    NASA Technical Reports Server (NTRS)

    Allison, Sidney G.; Shams, Qamar A.; Fox, Robert L.

    2008-01-01

    Assemblies containing curved piezoceramic fiber composite actuators have been invented as means of stretching optical fibers by amounts that depend on applied drive voltages. Piezoceramic fiber composite actuators are conventionally manufactured as sheets or ribbons that are flat and flexible, but can be made curved to obtain load-carrying ability and displacement greater than those obtainable from the flat versions. In the primary embodiment of this invention, piezoceramic fibers are oriented parallel to the direction of longitudinal displacement of the actuators so that application of drive voltage causes the actuator to flatten, producing maximum motion. Actuator motion can be transmitted to the optical fiber by use of hinges and clamp blocks. In the original application of this invention, the optical fiber contains a Bragg grating and the purpose of the controlled stretching of the fiber is to tune the grating as part of a small, lightweight, mode-hop-free, rapidly tunable laser for demodulating strain in Bragg-grating strain-measurement optical fibers attached to structures. The invention could also be used to apply controllable tensile force or displacement to an object other than an optical fiber.

  16. Stretched Exponential relaxation in pure Se glass

    NASA Astrophysics Data System (ADS)

    Dash, S.; Ravindren, S.; Boolchand, P.

    A universal feature of glasses is the stretched exponential relaxation, f (t) = exp[ - t / τ ] β . The model of diffusion of excitations to randomly distributed traps in a glass by Phillips1 yields the stretched exponent β = d[d +2] where d, the effective dimensionality. We have measured the enthalpy of relaxation ΔHnr (tw) at Tg of Se glass in modulated DSC experiments as glasses age at 300K and find β = 0.43(2) for tw in the 0

  17. Patents for stretching and shaping meats.

    PubMed

    Taylor, Johanne M; Hopkins, David L

    2011-05-01

    Attempts over the years to speed up the slaughter and processing of meat have been limited by the impact on important meat quality traits, such as tenderness. A number of methods and equipment have been developed for stretching and/or shaping to enhance the tenderness of meat, reducing the need for long term storage and ageing of meat. The more successful methods and equipment to improve the tenderness of meat - Tenderstretch (pelvic suspension), Tendercut (skeletal separation), SmartStretch™/Smartshape™ and Tenderbound (Pi-Vac Elasto-Pack system) are the subject of this review. Minimal research has been performed to compare these methods of tenderising meat. Tenderstretch and Tendercut are relatively easy to implement and require no specialised equipment, but they are relatively inflexible and only impact on a small number of muscles. The adoption of Tenderstretch has also been limited by increased resource requirements (chiller space and labour). SmartStretch™/Smartshape™ and Tenderbound, which wrap hot-boned pre-rigor muscles to prevent muscle contraction and shortening during rigor, are systems that do require specialised equipment. The major advantage of these systems is that they are very flexible and can be applied to any target muscle. Further research needs to be undertaken to compare these methods to better facilitate their commercial adoption. The article presents some promising patents on stretching and shaping meats. PMID:21428872

  18. Stretch sensors for human body motion

    NASA Astrophysics Data System (ADS)

    O'Brien, Ben; Gisby, Todd; Anderson, Iain A.

    2014-03-01

    Sensing motion of the human body is a difficult task. From an engineers' perspective people are soft highly mobile objects that move in and out of complex environments. As well as the technical challenge of sensing, concepts such as comfort, social intrusion, usability, and aesthetics are paramount in determining whether someone will adopt a sensing solution or not. At the same time the demands for human body motion sensing are growing fast. Athletes want feedback on posture and technique, consumers need new ways to interact with augmented reality devices, and healthcare providers wish to track recovery of a patient. Dielectric elastomer stretch sensors are ideal for bridging this gap. They are soft, flexible, and precise. They are low power, lightweight, and can be easily mounted on the body or embedded into clothing. From a commercialisation point of view stretch sensing is easier than actuation or generation - such sensors can be low voltage and integrated with conventional microelectronics. This paper takes a birds-eye view of the use of these sensors to measure human body motion. A holistic description of sensor operation and guidelines for sensor design will be presented to help technologists and developers in the space.

  19. Monte Carlo simulation of chromatin stretching.

    PubMed

    Aumann, Frank; Lankas, Filip; Caudron, Maïwen; Langowski, Jörg

    2006-04-01

    We present Monte Carlo (MC) simulations of the stretching of a single chromatin fiber. The model approximates the DNA by a flexible polymer chain with Debye-Hückel electrostatics and uses a two-angle zigzag model for the geometry of the linker DNA connecting the nucleosomes. The latter are represented by flat disks interacting via an attractive Gay-Berne potential. Our results show that the stiffness of the chromatin fiber strongly depends on the linker DNA length. Furthermore, changing the twisting angle between nucleosomes from 90 degrees to 130 degrees increases the stiffness significantly. An increase in the opening angle from 22 degrees to 34 degrees leads to softer fibers for small linker lengths. We observe that fibers containing a linker histone at each nucleosome are stiffer compared to those without the linker histone. The simulated persistence lengths and elastic moduli agree with experimental data. Finally, we show that the chromatin fiber does not behave as an isotropic elastic rod, but its rigidity depends on the direction of deformation: Chromatin is much more resistant to stretching than to bending. PMID:16711856

  20. Monte Carlo simulation of chromatin stretching

    NASA Astrophysics Data System (ADS)

    Aumann, Frank; Lankas, Filip; Caudron, Maïwen; Langowski, Jörg

    2006-04-01

    We present Monte Carlo (MC) simulations of the stretching of a single 30nm chromatin fiber. The model approximates the DNA by a flexible polymer chain with Debye-Hückel electrostatics and uses a two-angle zigzag model for the geometry of the linker DNA connecting the nucleosomes. The latter are represented by flat disks interacting via an attractive Gay-Berne potential. Our results show that the stiffness of the chromatin fiber strongly depends on the linker DNA length. Furthermore, changing the twisting angle between nucleosomes from 90° to 130° increases the stiffness significantly. An increase in the opening angle from 22° to 34° leads to softer fibers for small linker lengths. We observe that fibers containing a linker histone at each nucleosome are stiffer compared to those without the linker histone. The simulated persistence lengths and elastic moduli agree with experimental data. Finally, we show that the chromatin fiber does not behave as an isotropic elastic rod, but its rigidity depends on the direction of deformation: Chromatin is much more resistant to stretching than to bending.

  1. Stretching the Spines of Gymnasts: A Review.

    PubMed

    Sands, William A; McNeal, Jeni R; Penitente, Gabriella; Murray, Steven Ross; Nassar, Lawrence; Jemni, Monèm; Mizuguchi, Satoshi; Stone, Michael H

    2016-03-01

    Gymnastics is noted for involving highly specialized strength, power, agility and flexibility. Flexibility is perhaps the single greatest discriminator of gymnastics from other sports. The extreme ranges of motion achieved by gymnasts require long periods of training, often occupying more than a decade. Gymnasts also start training at an early age (particularly female gymnasts), and the effect of gymnastics training on these young athletes is poorly understood. One of the concerns of many gymnastics professionals is the training of the spine in hyperextension-the ubiquitous 'arch' seen in many gymnastics positions and movements. Training in spine hyperextension usually begins in early childhood through performance of a skill known as a back-bend. Does practising a back-bend and other hyperextension exercises harm young gymnasts? Current information on spine stretching among gymnasts indicates that, within reason, spine stretching does not appear to be an unusual threat to gymnasts' health. However, the paucity of information demands that further study be undertaken. PMID:26581832

  2. Levator Ani Muscle Stretch Induced by Simulated Vaginal Birth

    PubMed Central

    Lien, Kuo-Cheng; Mooney, Brian; DeLancey, John O. L.; Ashton-Miller, James A.

    2005-01-01

    OBJECTIVE: To develop a three-dimensional computer model to predict levator ani muscle stretch during vaginal birth. METHODS: Serial magnetic resonance images from a healthy nulliparous 34-year-old woman, published anatomic data, and engineering graphics software were used to construct a structural model of the levator ani muscles along with related passive tissues. The model was used to quantify pelvic floor muscle stretch induced during the second stage of labor as a model fetal head progressively engaged and then stretched the iliococcygeus, pubococcygeus, and puborectalis muscles. RESULTS: The largest tissue strain reached a stretch ratio (tissue length under stretch/original tissue length) of 3.26 in medial pubococcygeus muscle, the shortest, most medial and ventral levator ani muscle. Regions of the ileococcygeus, pubococcygeus, and puborectalis muscles reached maximal stretch ratios of 2.73, 2.50, and 2.28, respectively. Tissue stretch ratios were proportional to fetal head size: For example, increasing fetal head diameter by 9% increased medial pubococcygeus stretch by the same amount. CONCLUSION: The medial pubococcygeus muscles undergo the largest stretch of any levator ani muscles during vaginal birth. They are therefore at the greatest risk for stretch-related injury. PMID:14704241

  3. Membrane stretch and cytoplasmic Ca2+ independently modulate stretch-activated BK channel activity.

    PubMed

    Zhao, Hu-Cheng; Agula, Hasi; Zhang, Wei; Wang, Fa; Sokabe, Masahiro; Li, Lu-Ming

    2010-11-16

    Large conductance Ca(2+)-activated K(+) (BK) channels are responsible for changes in chemical and physical signals such as Ca(2+), Mg(2+) and membrane potentials. Previously, we reported that a BK channel cloned from chick heart (SAKCaC) is activated by membrane stretch. Molecular cloning and subsequent functional characterization of SAKCaC have shown that both the membrane stretch and intracellular Ca(2+) signal allosterically regulate the channel activity via the linker of the gating ring complex. Here we investigate how these two gating principles interact with each other. We found that stretch force activated SAKCaC in the absence of cytoplasmic Ca(2+). Lack of Ca(2+) bowl (a calcium binding motif) in SAKCaC diminished the Ca(2+)-dependent activation, but the mechanosensitivity of channel was intact. We also found that the abrogation of STREX (a proposed mechanosensing apparatus) in SAKCaC abolished the mechanosensitivity without altering the Ca(2+) sensitivity of channels. These observations indicate that membrane stretch and intracellular Ca(2+) could independently modulate SAKCaC activity. PMID:20673577

  4. Identification of CFC and HCFC substitutes for blowing polyurethane foam insulation products. Report for September 1993-August 1994

    SciTech Connect

    Howard, P.H.; Tunkel, J.L.; Hendriks, R.V.

    1996-04-01

    The paper gives results of a systematic search to identify additional candidates as third-generation blowing agents, chemical compounds that are not stratospheric ozone depleters that can be used as substitutes for chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) blowing agents in rigid polyurethane foam insulating materials. To identify the most promising substitutes, potential third-generation blowing agents were ranked using a methodology developed for this project.

  5. Near surface flow structure over a dimpled surface with blowing

    NASA Astrophysics Data System (ADS)

    Borchetta, Colby; Martin, Alexandre; Bailey, Sean

    2015-11-01

    The combined effects of surface roughness with flow injection are of particular interest in understanding the flow over ablative heat-shields, a common form of thermal protection system (TPS) used for atmospheric entry. Stereoscopic, time-resolved particle image velocimetry was used to investigate the near-surface flow over a surface geometry consisting of hexagonal dimples, typical of a TPS. Of particular interest are the modifications made to the flow structures generated by the dimpled elements caused by flow injection through the surface. Without flow injection, inclined flow structures are generated periodically at the upstream edge of the dimples and convected downstream. This behavior is coupled with fluid becoming entrained inside the dimples, recirculating and ejecting away from the surface. When flow injection occurs through the surface, this process occupies a larger region of the flow, extending further from the surface, with a corresponding increase in the size of the convecting structures and increase in turbulent kinetic energy. These features persist over the range of Reynolds numbers investigated, with increasing Reynolds number resulting in increased turbulence and a corresponding broadening of the region of the flow influenced by the surface. This research is supported by NASA Award NNX13AN04A.

  6. Simulation on Decarburization and Inclusion Removal Process in the Ruhrstahl-Heraeus (RH) Process with Ladle Bottom Blowing

    NASA Astrophysics Data System (ADS)

    Geng, Dian-Qiao; Zheng, Jin-Xing; Wang, Kai; Wang, Ping; Liang, Ru-Quan; Liu, Hai-Tao; Lei, Hong; He, Ji-Cheng

    2015-03-01

    To enhance the refining efficiency of the Ruhrstahl-Heraeus (RH) process, the ladle bottom blowing was employed in RH degasser and a numerical method was employed to investigate the decarburization and inclusion removal in RH with ladle bottom blowing. The results showed that the decarburization rate in RH with ladle bottom blowing is greater than that in traditional RH. The larger mass fraction of carbon at the recirculation zone under up snorkel disappears because of the gas bubbles from ladle bottom blowing in an RH degasser. For RH with ladle bottom blowing, the decarburization at argon bubble surface accounts for the majority of the removed carbon, and it is approximately two times greater than that in the inner site of the vacuum chamber. Besides, the inclusion removal rate in RH with ladle bottom blowing is greater than that in traditional RH, and the maximum inclusion characteristic radius is much less in RH with ladle bottom blowing than that in traditional RH. Besides, the accumulation of inclusions in ladle between sidewall and up snorkel and the recirculation zone under up snorkel, which can be found in traditional RH, disappears in RH with ladle bottom blowing. For RH with ladle bottom blowing, the average number density of inclusions decreases more drastically than that in traditional RH and the average terminal number density of inclusions is much smaller than that in traditional RH.

  7. Numerical study of blow-up and dispersive shocks in solutions to generalized Korteweg-de Vries equations

    NASA Astrophysics Data System (ADS)

    Klein, C.; Peter, R.

    2015-06-01

    We present a detailed numerical study of solutions to general Korteweg-de Vries equations with critical and supercritical nonlinearity, both in the context of dispersive shocks and blow-up. We study the stability of solitons and show that they are unstable against being radiated away and blow-up. In the L2 critical case, the blow-up mechanism by Martel, Merle and Raphaël can be numerically identified. In the limit of small dispersion, it is shown that a dispersive shock always appears before an eventual blow-up. In the latter case, always the first soliton to appear will blow up. It is shown that the same type of blow-up as for the perturbations of the soliton can be observed which indicates that the theory by Martel, Merle and Raphaël is also applicable to initial data with a mass much larger than the soliton mass. We study the scaling of the blow-up time t∗ in dependence of the small dispersion parameter ɛ and find an exponential dependence t∗(ɛ) and that there is a minimal blow-up time t0∗ greater than the critical time of the corresponding Hopf solution for ɛ → 0. To study the cases with blow-up in detail, we apply the first dynamic rescaling for generalized Korteweg-de Vries equations. This allows to identify the type of the singularity.

  8. A consideration on the electric field formed by blowing snow particles

    NASA Astrophysics Data System (ADS)

    Omiya, Satoshi; Sato, Atsushi

    2013-04-01

    Fluctuations of the atmospheric electric field strength have been reported during blowing snow events. A primary factor of this phenomenon is the electrification of the blowing snow particles. Electric force applied to the blowing snow particles may be a contributing factor in the formation of snow drifts and snow cornices and changing particles' trajectory motion. These can cause natural disaster such as an avalanche and visibility deterioration. Therefore, charging phenomenon of the blowing snow particles is an important issue in terms of not only precise understanding of the particle motion but disaster prevention. The purpose of this study was to clarify the fluctuation characteristics of the electric field. In previous studies, some numerical models have been proposed; however, these models did not consider the dependency of the particle charges on the particle diameter or the height dependency of the horizontal mass flux. Taking into account those dependencies, we estimated the vertical electric field distribution. In this study, an experimental equation (Omiya et al., 2011), which can estimate the individual particle charge from the particle diameter and the air temperature, was used. In addition, the approximation equations of the vertical distribution of wind speed, the horizontal mass flux, and the average particle diameter were also used. A hot-wire anemometer was used to measure the wind speed. A snow particle counter (SPC) was used to measure the horizontal mass flux and the particle diameter distribution. This experiment was conducted in a cold wind tunnel (Ice and Snow Research Center, NIED, JAPAN) at an air temperature of -10 degree Celsius. In this calculation, for simplicity, some assumptions were considered; 1) The particle diameter and the particle number density are horizontally constant and uniform. (The electric field formed by the blowing snow particles is uniform horizontally.) 2) All the blowing snow particles are electrified negatively

  9. Super-Eddington Atmospheres That Do Not Blow Away

    NASA Astrophysics Data System (ADS)

    Begelman, Mitchell C.

    2001-04-01

    We show that magnetized, radiation-dominated atmospheres can support steady state patterns of density inhomogeneity that enable them to radiate at far above the Eddington limit without suffering mass loss. The inhomogeneities consist of periodic shock fronts bounding narrow, high-density regions, interspersed with much broader regions of low density. The flow of radiation avoids the dense regions, which are therefore weighed down by gravity, while gas in the low-density regions is slammed upward into the shock fronts by radiation force. As the wave pattern moves through the atmosphere, each parcel of matter alternately experiences upward and downward forces, which balance on average. We calculate the density structure and phase speed of the wave pattern and relate these to the density contrast and the factor by which the net radiation flux exceeds the Eddington limit. The presence of a magnetic field is essential for the existence of these flows since magnetic tension shares the competing forces between regions of different densities, preventing the atmosphere from blowing apart. There appears to be a broad family of modes propagating in arbitrary directions with respect to the direction of the mean magnetic field and exhibiting a range of density contrasts. While the transition from low to high density occurs through a strong shock, the gas must pass through a slow magnetosonic critical point in order to return to the low-density state. The flux of radiation escaping from the atmosphere exceeds the Eddington limit by a factor of order the square root of the ratio between maximum and minimum density. In principle, this factor can be as large as the ratio of magnetic pressure to mean gas pressure. Although the magnetic pressure must be large compared to the mean gas pressure in order to support a large density contrast, it need not be large compared to the radiation pressure. These highly inhomogeneous flows could represent the nonlinear development of the ``photon

  10. Current concepts on the management of orbital blow-out fractures.

    PubMed

    Koornneef, L

    1982-09-01

    Surgical versus nonsurgical treatment of orbital blow-out fractures has been controversial in the past. In the 1950s it was advocated that all blow-out fractures be treated surgically based on the conception that extraocular muscles were blown out and trapped in the fracture hole, causing double vision and enophthalmos. Gradually, however, a shift to a more conservative approach occurred, probably because of the complications of surgery, the disappointing results in improvement of motility and enophthalmos, and the growing evidence of spontaneous improvement of double vision. This article analyzes the literature chronologically and blends this analysis with the results of a new anatomical approach to the human orbit. New theories on the mechanism of blow-out fractures are postulated. No longer is entrapment of muslces in a blow-out fracture held responsible for the severe motility problems; rather it is viewed as caused by a dysfunction of the entire motility apparatus in the fracture region. Consequently, conventional surgical treatment, repairing the orbital floor only, seems to have lost its theoretical foundation and a conservative approach is advocated until microsurgical techniques become more readily avaliable to treat the sequelae of blow-out fractures at their origin. PMID:7137815

  11. Laminar and turbulent flows over spherically blunted cone and hyperboloid with massive surface blowing

    NASA Technical Reports Server (NTRS)

    Kumar, A.; Twari, S. N.

    1979-01-01

    Numerical solutions are presented for the flow over a spherically blunted cone and hyperboloid with massive surface blowing. Time-dependent viscous shock-layer equations are used to describe the flow field. The boundary conditions on the body surface include a prescribed blowing-rate distribution. The governing equations are solved by a time-asymptotic finite-difference method. Results presented here are only for a perfect gas-type flow at zero angle of attack. Both laminar and turbulent flow solutions are obtained. It is found that the effect of the surface blowing on the laminar flow field is to smooth out the curvature discontinuity at the sphere-cone juncture point, which results in a positive pressure gradient over the body. The shock slope increases on the downstream portion of the body as the surface blowing rate is increased. The turbulent flow with surface blowing is found to redevelop a boundary-layer-like region near the surface. The effects of this boundary-layer region on the flow field and heating rates are discussed.

  12. Scattering and sequestering of blow-up moduli in local string models

    NASA Astrophysics Data System (ADS)

    Conlon, Joseph P.; Witkowski, Lukas T.

    2011-12-01

    We study the scattering and sequestering of blow-up fields - either local to or distant from a visible matter sector - through a CFT computation of the dependence of physical Yukawa couplings on the blow-up moduli. For a visible sector of D3-branes on orbifold singularities we compute the disk correlator left< {tau_s^{{(1)}}tau_s^{{(2)}}...tau_s^{{(n)}}ψ ψ φ } rightrangle between orbifold blow-up moduli and matter Yukawa couplings. For n = 1 we determine the full quantum and classical correlator. This result has the correct factorisation onto lower 3-point functions and also passes numerous other consistency checks. For n > 1 we show that the structure of picture-changing applied to the twist operators establishes the sequestering of distant blow-up moduli at disk level to all orders in α'. We explain how these results are relevant to suppressing soft terms to scales parametrically below the gravitino mass. By giving vevs to the blow-up fields we can move into the smooth limit and thereby derive CFT results for the smooth Swiss-cheese Calabi-Yaus that appear in the Large Volume Scenario.

  13. Computational analysis of forebody tangential slot blowing on the high alpha research vehicle

    NASA Technical Reports Server (NTRS)

    Gee, Ken

    1994-01-01

    Current and future fighter aircraft can maneuver in the high-angle-of-attack flight regime while flying at low subsonic and transonic freestream Mach numbers. However, at any flight speed, the ability of the vertical tails to generate yawing moment is limited in high-angle-of-attack flight. Thus, any system designed to provide the pilot with additional side force and yawing moment must work in both low subsonic and transonic flight. However, previous investigations of the effectiveness of forebody tangential slot blowing in generating the desired control forces and moments have been limited to the low subsonic freestream flow regime. In order to investigate the effectiveness of tangential slot blowing in transonic flight, a computational fluid dynamics analysis was carried out during the grant period. Computational solutions were obtained at three different freestream Mach numbers and at various jet mass flow ratios. All results were obtained using the isolated F/A-18 forebody grid geometry at 30.3 degrees angle of attack. One goal of the research was to determine the effect of freestream Mach number on the effectiveness of forebody tangential slot blowing in generating yawing moment. The second part of the research studied the force onset time lag associated with blowing. The time required for the yawing moment to reach a steady-state value from the onset of blowing may have an impact on the implementation of a pneumatic system on a flight vehicle.

  14. On the effect of leading edge blowing on circulation control airfoil aerodynamics

    NASA Technical Reports Server (NTRS)

    Mclachlan, B. G.

    1987-01-01

    In the present context the term circulation control is used to denote a method of lift generation that utilizes tangential jet blowing over the upper surface of a rounded trailing edge airfoil to determine the location of the boundary layer separation points, thus setting an effective Kutta condition. At present little information exists on the flow structure generated by circulation control airfoils under leading edge blowing. Consequently, no theoretical methods exist to predict airfoil performance under such conditions. An experimental study of the flow field generated by a two dimensional circulation control airfoil under steady leading and trailing edge blowing was undertaken. The objective was to fundamentally understand the overall flow structure generated and its relation to airfoil performance. Flow visualization was performed to define the overall flow field structure. Measurements of the airfoil forces were also made to provide a correlation of the observed flow field structure to airfoil performance. Preliminary results are presented, specifically on the effect on the flow field structure of leading edge blowing, alone and in conjunction with trailing edge blowing.

  15. The influence of passive stretch on muscle oxygen saturation.

    PubMed

    McCully, Kevin K

    2010-01-01

    Previous studies have suggested that chronic stretch might be able to produce skeletal muscle hypertrophy. However, stretching might also restrict blood flow, which could in turn influence any stretch-training program. This study evaluated the influence of muscle stretch on muscle oxygen saturation using near infrared spectroscopy (NIRS). A 16 channel NIRS probes were placed on the medial gastrocnemius, quadriceps, and hamstring muscles of young healthy adults. Oxygen saturation during maximal tolerated stretch was measured and normalized with cuff-induced ischemia and reperfusion. Oxygen saturation decreased in the gastrocnemius and quadriceps in a position dependent fashion, but did not change in the hamstring muscles. Passive stretching may also have a significant hypoxic component in some muscles but not others. PMID:20204809

  16. Effects of stretching the scalene muscles on slow vital capacity.

    PubMed

    Lee, Juncheol; Hwang, Sehee; Han, Seungim; Han, Dongwook

    2016-06-01

    [Purpose] The purpose of this study was to examine whether stretching of the scalene muscles would improve slow vital capacity (SVC). [Subjects and Methods] The subjects of this study were 20 healthy female students to whom the study's methods and purpose were explained and their agreement for participation was obtained. The SVC was measured using spirometry (Pony FX, COSMED Inc., Italy). The intervention used was stretching of the scalene muscles. Stretching was carried out for 15 min, 10 times at per each portion of scalene muscles: the anterior, middle, and posterior parts. [Results] Expiratory vital capacity (EVC) and tidal volume (Vt) noticeably increased after stretching. However, there were no changes in any of the SVC items in the control group. [Conclusion] This study demonstrated that stretching of the scalene muscles can effectively improve SVC. In particular, we confirmed that stretching of the scalene muscles was effective in increasing EVC and Vt, which are items of SVC. PMID:27390425

  17. Effects of stretching the scalene muscles on slow vital capacity

    PubMed Central

    Lee, Juncheol; Hwang, Sehee; Han, Seungim; Han, Dongwook

    2016-01-01

    [Purpose] The purpose of this study was to examine whether stretching of the scalene muscles would improve slow vital capacity (SVC). [Subjects and Methods] The subjects of this study were 20 healthy female students to whom the study’s methods and purpose were explained and their agreement for participation was obtained. The SVC was measured using spirometry (Pony FX, COSMED Inc., Italy). The intervention used was stretching of the scalene muscles. Stretching was carried out for 15 min, 10 times at per each portion of scalene muscles: the anterior, middle, and posterior parts. [Results] Expiratory vital capacity (EVC) and tidal volume (Vt) noticeably increased after stretching. However, there were no changes in any of the SVC items in the control group. [Conclusion] This study demonstrated that stretching of the scalene muscles can effectively improve SVC. In particular, we confirmed that stretching of the scalene muscles was effective in increasing EVC and Vt, which are items of SVC. PMID:27390425

  18. Flow visualization of discrete-hole film cooling with spanwise injection over a cylinder

    NASA Technical Reports Server (NTRS)

    Russell, L. M.

    1979-01-01

    Insight into the fluid mechanics encountered when film air from a single row of holes is injected over a cylinder in a mainstream at conditions simulating a film cooled, turbulent-vane leading edge was investigated. Smoke was added to the cooling air to visualize its flow path. Film was injected in the spanwise direction at angles of 30 deg and 45 deg to the surface; at angular locations of 15 deg, 30 deg, 45 deg, and 60 deg from the stagnation line; and at various blowing ratios. The observations were related to the measured heat transfer data of others. The results indicate that, in addition to the expected growth in film thickness and the greater penetration of the boundary layer with increasing blowing ration, there was an absence of spanwise spreading and only a small spanwise deflection of the injected film.

  19. Aerothermodynamic properties of stretched flames in enclosures

    NASA Astrophysics Data System (ADS)

    Rotman, D. A.; Oppenheim, A. K.

    Flames are stretched by being pulled along their frontal surface by the flow field in which they reside. Their trajectories tend to approach particle paths, acquiring eventually the role of contact boundaries, -interfaces between the burnt and unburnt medium that may broaden solely as a consequence of diffusion. Fundamental properties of flow fields governing such flames are determined here on the basis of the zero Mach number model, providng a rational method of approach to the computational analysis of combustion fields in enclosures where, besides the aerodynamic properties flow, the thermodynamic process of compression must be taken into account. To illustrate its application, the method is used to reveal the mechanism of formation of a tulip-shape flame in a rectangular enclosure under nonturbulent flow conditions.

  20. Universal stretched exponential relaxation in nanoconfined water

    NASA Astrophysics Data System (ADS)

    Shekhar, Adarsh; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya; Alm, Camilla K.; Malthe-Sørenssen, Anders

    2014-10-01

    Understanding the behavior of water confined at the nanometer scale is a fundamental problem not only in physics but also in life sciences, geosciences, and atmospheric sciences. Here, we examine spatial and dynamic heterogeneities in water confined in nanoporous silica using molecular dynamics (MD) simulations. The simulations reveal intermixed low-density water and high-density water with distinct local structures in nanopores of silica. The MD simulations also show dynamic heterogeneities in nanoconfined water. The temporal decay of cage correlation functions for room temperature and supercooled, nanoconfined water is very well described by stretched exponential relaxation, exp(-(t/τ)β). The exponent β has a unique value, d/(d + 2), which agrees with an exact result for diffusion in systems with static, random traps in d = 3 dimensions.

  1. Stretched Lens Array Photovoltaic Concentrator Technology Developed

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael F., Jr.; O'Neill, Mark J.

    2004-01-01

    Solar arrays have been and continue to be the mainstay in providing power to nearly all commercial and government spacecraft. Light from the Sun is directly converted into electrical energy using solar cells. One way to reduce the cost of future space power systems is by minimizing the size and number of expensive solar cells by focusing the sunlight onto smaller cells using concentrator optics. The stretched lens array (SLA) is a unique concept that uses arched Fresnel lens concentrators to focus sunlight onto a line of high-efficiency solar cells located directly beneath. The SLA concept is based on the Solar Concentrator Array with Refractive Linear Element Technology (SCARLET) design that was used on NASA's New Millennium Deep Space 1 mission. The highly successful asteroid/comet rendezvous mission (1998 to 2001) demonstrated the performance and long-term durability of the SCARLET/SLA solar array design and set the foundation for further improvements to optimize its performance.

  2. Force fluctuations in stretching a tethered polymer

    NASA Astrophysics Data System (ADS)

    Varghese, Anoop; Vemparala, Satyavani; Rajesh, R.

    2013-08-01

    The recently proposed fluctuation relation in unfolding forces [Phys. Rev. E1539-375510.1103/PhysRevE.84.060101 84, 060101(R) (2011)] is reexamined taking into account the explicit time dependence of the force distribution. The stretching of a tethered Rouse polymer is exactly solved and the ratio of the probabilities of positive to negative forces is shown to be an exponential in force. Extensive steered molecular dynamics simulations of unfolding of deca alanine peptide confirm the form of fluctuation relation proposed earlier, but with explicit correct time dependence of unfolding forces taken into account. From exact calculations and simulations, a linear dependence of the constant in the exponential of the fluctuation relation on average unfolding forces and inverse temperature is proposed.

  3. Mechanical stretching of proteins: calmodulin and titin

    NASA Astrophysics Data System (ADS)

    Cieplak, Marek

    2005-07-01

    Mechanical unfolding of several domains of calmodulin and titin is studied using a Go-like model with a realistic contact map and Lennard-Jones contact interactions. It is shown that this simple model captures the experimentally observed difference between the two proteins: titin is a spring that is tough and strong whereas calmodulin acts like a weak spring with featureless force-displacement curves. The difference is related to the dominance of the α secondary structures in the native structure of calmodulin. The tandem arrangements of calmodulin unwind simultaneously in each domain whereas the domains in titin unravel in a serial fashion. The sequences of contact events during unravelling are correlated with the contact order, i.e., with the separation between contact making amino acids along the backbone in the native state. Temperature is found to affect stretching in a profound way.

  4. Constellation Stretch Goals: Review of Industry Inputs

    NASA Technical Reports Server (NTRS)

    Lang, John

    2006-01-01

    Many good ideas received based on industry experience: a) Shuttle operations; b) Commercial aircraft production; c) NASA's historical way of doing business; d) Military and commercial programs. Aerospace performed preliminary analysis: a) Potential savings; b) Cost of implementation; c) Performance or other impact/penalties; d) Roadblocks; e) Unintended consequences; f) Bottom line. Significant work ahead for a "Stretch Goal"to become a good, documented requirement: 1) As a group, the relative "value" of goals are uneven; 2) Focused analysis on each goal is required: a) Need to ensure that a new requirement produces the desired consequence; b) It is not certain that some goals will not create problems elsewhere. 3) Individual implementation path needs to be studied: a) Best place to insert requirement (what level, which document); b) Appropriate wording for the requirement. Many goals reflect "best practices" based on lessons learned and may have value beyond near-term CxP requirements process.

  5. Implicit learning and generalization of stretch response modulation in humans.

    PubMed

    Turpin, Nicolas A; Levin, Mindy F; Feldman, Anatol G

    2016-06-01

    Adaptation of neural responses to repeated muscle stretching likely represents implicit learning to minimize muscle resistance to perturbations. To test this hypothesis, the forearm was placed on a horizontal manipulandum. Elbow flexors or extensors compensated an external load and were stretched by 20° or 70° rotations. Participants were instructed not to intervene by intentionally modifying the muscle resistance elicited by stretching. In addition to phasic stretch reflexes (SRs), muscle stretching was associated with inhibitory periods (IPs) in the ongoing muscle activity starting at minimal latencies of ∼35 ms. The SR amplitude decreased dramatically across 5-12 trials and was not restored after a resting period of 3-5 min, despite the increase in stretch amplitude from 20° to 70°, but IPs remained present. When SRs were suppressed, stretching of originally nonstretched, antagonist muscles initiated after the rest period showed immediate SR suppression while IPs remained present in the first and subsequent trials. Adaptation to muscle stretching thus includes features characteristic of implicit learning such as memory consolidation and generalization. Adaptation may be achieved by central shifts in the threshold positions at which muscles begin to be activated. Shifts are thought to be prepared in advance and triggered with stretch onset. Threshold position resetting provides a comprehensive explanation of the results in the broader context of the control of posture, movement, and motor learning in the healthy and damaged nervous system. PMID:27052586

  6. Sh-Stretching Intensities and Intramolecular Hydrogen Bonding in Alkanethiols

    NASA Astrophysics Data System (ADS)

    Miller, B. J.; Lane, J. R.; Sodergren, A. H.; Kjaergaard, H. G.; Dunn, M. E.; Vaida, V.

    2009-06-01

    The SH-stretching overtone transitions of tert-butylthiol and ethanethiol are observed using FT-IR, NIR and photoacoustic spectroscopies. The intensities of these are compared with OH-stretching overtones from the corresponding alcohols. We explain the paucity of SH-stretching intensity using an anharmonic oscillator local mode model. SH- and OH-stretching overtone spectra of 1,2-ethanedithiol and 2-mercaptoethanol are recorded to observe the different effects that hydrogen bonding involving SH - - - S, SH - - - O and OH - - - S have on the spectra. We discuss these effects with the help of high level ab initio calculations.

  7. Do Stretch Durations Affect Muscle Mechanical and Neurophysiological Properties?

    PubMed

    Opplert, J; Genty, J-B; Babault, N

    2016-08-01

    The aim of the study was to determine whether stretching durations influence acute changes of mechanical and neurophysiological properties of plantar flexor muscles. Plantar flexors of 10 active males were stretched in passive conditions on an isokinetic dynamometer. Different durations of static stretching were tested in 5 randomly ordered experimental trials (1, 2, 3, 4 and 10×30-s). Fascicle stiffness index, evoked contractile properties and spinal excitability (Hmax/Mmax) were examined before (PRE), immediately after (POST0) and 5 min after (POST5) stretching. No stretch duration effect was recorded for any variable. Moreover, whatever the stretching duration, stiffness index, peak twitch torque and rate of force development were significantly lower at POST0 and POST5 as compared to PRE (P<0.05). Electromechanical delay was longer at POST0 and POST5 as compared to PRE (P<0.05). Whatever the stretch duration, no significant changes of Hmax/Mmax ratio were recorded. In conclusion, 30 s of static stretching to maximum tolerated discomfort is sufficient enough to alter mechanical properties of plantar flexor muscles, but 10×30 s does not significantly affect these properties further. Stretching does not impair spinal excitability. PMID:27191211

  8. Large Deviation Statistics of Vorticity Stretching in Isotropic Turbulence

    NASA Astrophysics Data System (ADS)

    Johnson, Perry; Meneveau, Charles

    2015-11-01

    A key feature of 3D fluid turbulence is the stretching/re-alignment of vorticity by the action of the strain-rate. It is shown using the cumulant-generating function that cumulative vorticity stretching along a Lagrangian path in isotropic turbulence behaves statistically like a sum of i.i.d. variables. The Cramer function for vorticity stretching is computed from the JHTDB isotropic DNS (Reλ = 430) and compared to those of the finite-time Lyapunov exponents (FTLE) for material deformation. As expected the mean cumulative vorticity stretching is slightly less than that of the most-stretched material line (largest FTLE), due to the vorticity's preferential alignment with the second-largest eigenvalue of strain-rate and the material line's preferential alignment with the largest eigenvalue. However, the vorticity stretching tends to be significantly larger than the second-largest FTLE, and the Cramer functions reveal that the statistics of vorticity stretching fluctuations are more similar to those of largest FTLE. A model Fokker-Planck equation is constructed by approximating the viscous destruction of vorticity with a deterministic non-linear relaxation law matching conditional statistics, while the fluctuations in vorticity stretching are modelled by stochastic noise matching the statistics encoded in the Cramer function. The model predicts a stretched-exponential tail for the vorticity magnitude PDF, with good agreement for the exponent but significant error (30-40%) in the pre-factor. Supported by NSF Graduate Fellowship (DGE-1232825) and NSF Grant CMMI-0941530.

  9. Enhancement of multispectral thermal infrared images - Decorrelation contrast stretching

    NASA Technical Reports Server (NTRS)

    Gillespie, Alan R.

    1992-01-01

    Decorrelation contrast stretching is an effective method for displaying information from multispectral thermal infrared (TIR) images. The technique involves transformation of the data to principle components ('decorrelation'), independent contrast 'stretching' of data from the new 'decorrelated' image bands, and retransformation of the stretched data back to the approximate original axes, based on the inverse of the principle component rotation. The enhancement is robust in that colors of the same scene components are similar in enhanced images of similar scenes, or the same scene imaged at different times. Decorrelation contrast stretching is reviewed in the context of other enhancements applied to TIR images.

  10. Constraint effects observed in crack initiation stretch

    SciTech Connect

    Lambert, D.M.; Ernst, H.A.

    1995-12-31

    The current paper characterizes constraint in fracture: J-modified resistance (Jr) curves were developed for two tough structural materials, 6061-T651 (aluminum) and IN718-STA1 (nickel-base superalloy). A wide variety of configurations was tested to consider load configurations from bending to tension including three specimen types (compact tension, center-crack tension, and single-edge notched tension), and a range of ligament lengths and thicknesses, as well as side-grooved and smooth-sided ligaments. The Jr curves exhibited an inflection point after some crack extension, and the data were excluded beyond the inflection. Qualified Jr curves for the two materials showed similar behavior, but R-curves were identical for equal ligament length-to-thickness ratio (RL), for the aluminum alloy, with increasing slope for increasing RL, while for the nickel, the resistance curves aligned for equal ligament thickness, B, and the slope increased for decreasing B. Displacements at the original crack tip (CToD) were recorded throughout the test for several specimens. CToD-versus-crack extension curves were developed, and data were excluded beyond the inflection point (as with the Jr curves). The data collapsed into two distinct curves, thought to represent the surface, plane stress effect and the central, plane strain effect. This was observed for both materials. A technique called profiling is presented for the aluminum alloy only, where the crack face displacements are recorded at the final point of the test as a function of the position throughout the crack cavity, along with an effort to extract the observations in a usable form. Displacements were consistent throughout the cross-section at and behind the original crack tip. In the region where the crack grew, this displacement was developed by a combination of stretch and crack growth. The stretch required to initiate crack extension was a function of the depth beneath the surface into the cross-section.

  11. Development of a stretched-membrane dish

    SciTech Connect

    Not Available

    1991-07-01

    Solar Kinetics, Inc., successfully designed and constructed the optical element of a 7-meter diameter stretched-membrane dish as Task 2 of the second phase of a contract directed by Sandia National Laboratories. Earlier work on this project defined the configuration of the optical element and demonstrated the membrane-forming process on 1.4- and 3.7-meter diameter membranes. In Task 2, the membrane-forming process was successfully scaled to 7-meters in diameter, and an innovative hub-and-spoke structure optical element was fabricated. The slope error, as measured with Solar Kinetics' laser-ray-trace system, was within 3.6 mrad of a perfect parabola. Four major technical issues were successfully addressed in this work: (1) The technique of large-scale membrane forming was shown to be predictable, accurate, and repeatable. Three 7-meter membranes were formed without any contoured tooling. (2) A tensioned hub-and-spoke structure was demonstrated to be practical to fabricate. This innovative structure, like a bicycle wheel, was shown to be very stiff. Optical effects from ring distortion were not apparent. (3) The use of field-replaceable, unattached polymer reflective membrane was demonstrated. This approach allows for the practical field replacement of the reflective membrane when it has degraded due to weathering. (4) A technique was developed and demonstrated to ship the formed membranes from the factory to the dish-installation site. This allows the critical forming of the membrane to be performed in a controlled factory environment, and the membrane then to be shipped using standard-dimension shipping containers. This development further reduces manufacturing and installation costs of the completed dish. This effort indicates that the stretch-membrane dish concept is a promising approach for solar concentration. The prototype optical element is a significant step in the development of the complete, full-sized dish. 9 refs., 53 figs., 2 tabs.

  12. Diagnosing the PEP-II Injection System

    SciTech Connect

    Decker, F.-J.; Donald, M.H.; Iverson, R.H.; Kulikov, A.; Pappas, G.C.; Weaver, M.; /SLAC

    2005-05-09

    The injection of beam into the PEP-II B-Factory, especially into the High Energy Ring (HER) has some challenges. A high background level in the BaBar detector has for a while inhibited us from trickling charge into the HER similar to the Low Energy Ring (LER). Analyzing the injection system has revealed many issues which could be improved. The injection bump between two kickers was not closed, mainly because the phase advance wasn't exactly 180{sup o} and the two kicker strengths were not balanced. Additionally we found reflections which kick the stored beam after the main kick and cause the average luminosity to drop about 3% for a 10 Hz injection rate. The strength of the overall kick is nearly twice as high as the design, indicating a much bigger effective septum thickness. Compared with single beam the background is worse when the HER beam is colliding with the LER beam. This hints that the beam-beam force and the observed vertical blow-up in the HER pushes the beam and especially the injected beam further out to the edge of the dynamic aperture or beyond.

  13. Free-Flight Evaluation of Forebody Blowing for Yaw Control at High Angels of Attack

    NASA Technical Reports Server (NTRS)

    Kiddy, Jason

    1995-01-01

    Forebody blowing is a concept developed to provide yaw control for aircraft flying at high angles of attack where a conventional rudder becomes ineffective. The basic concept is fairly simple. A small jet of air is forced out of the nose of the aircraft. This jet causes a repositioning of the forebody vortices in an asymmetrical fashion. The asymmetric forebody vortex flows develop a side force on the forebody which results in substantial yawing moments at high angles of attack. The purpose of this project was to demonstrate the use of forebody blowing as a control device through free-flight evaluation. This unique type of testing was performed at the NASA-Langley 30- by 60-foot tunnel. From these tests, it could then be shown that forebody blowing is an effective method of maintaining yaw control at high angles of attack.

  14. Performance of a V/STOL tilt nacelle inlet with blowing boundary layer control

    NASA Technical Reports Server (NTRS)

    Johns, A. L.; Williams, R. C.; Potonides, H. C.

    1979-01-01

    A scale model of a V/STOL tilt nacelle fitted to a 0.508 m single stage fan was tested in the NASA Lewis 9x15 ft low speed wind tunnel to determine the effect of diffuser blowing on the inlet aerodynamics and aeromechanical performance. The test was conducted over a range of freestream speeds (up to 120 knots) and angles of attack (up to 120 deg). Diffuser blowing had a beneficial affect on all performance parameters. The angle of attack range for separation free flow substantially increased, and the fan face distortion significantly reduced with a corresponding increase in total pressure recovery. Discrete narrow band blade stress peaks which were common to the nonblowing (baseline) configuration were eradicated with diffuser blowing.

  15. Effects of wall suction/blowing on two-dimensional flow past a confined square cylinder.

    PubMed

    Zhang, Wei; Jiang, Yanqun; Li, Lang; Chen, Guoping

    2016-01-01

    A numerical simulation is conducted to study the laminar flow past a square cylinder confined in a channel (the ratio of side length of the square to channel width is fixed at 1/4) subjected to a locally uniform blowing/suction speed placed at the top and bottom channel walls. Governing equations with boundary conditions are resolved using a finite volume method in pressure-velocity formulation. The flow patterns relevant to the critical spacing values are investigated. Numerical results show that wall blowing has a stabilizing effect on the flow, and the corresponding critical Reynolds number increases monotonically with increasing blowing velocity. Remarkably, steady asymmetric solutions and hysteretic mode transitions exist in a certain range of parameters (Reynolds number and suction speed) in the case of suction. PMID:27462481

  16. Performance of a V/STOL tilt nacelle inlet with blowing boundary layer control

    NASA Technical Reports Server (NTRS)

    Johns, A. L.; Williams, R. C.; Potonides, H. C.

    1979-01-01

    A scale model of a V/STOL tilt nacelle fitted to a 0.508 m single stage fan was tested in the NASA Lewis low speed wind tunnel to determine the effect of diffuser blowing on the inlet aerodynamics and aeromechanical performance. The test was conducted over a range of freestream speeds (up to 120 knots) and angles-of attack (up to 120 deg). In general, diffuser blowing had a beneficial affect on all performance parameters. The angle-of-attack range for a separation-free flow substantially increased, and the fan face distortion reduced with a corresponding increase in total pressure recovery. Discrete narrow band blade stress peaks which were common to the nonblowing (baseline) configuration were eradicated with diffuser blowing.

  17. On the shape of blow-up solutions to a mean field equation

    NASA Astrophysics Data System (ADS)

    Bartolucci, Daniele; Montefusco, Eugenio

    2006-03-01

    We analyse the structure of non-radial N-point blow up solutions sequences for the Liouville type equation on the two-dimensional unit disc, \\[ \\begin{equation*}\\fl -\\Delta u(x)=\\lambda \\displaystyle{\\frac{|x|^{2\\alpha}\\exp({u(x)})}{\\int_{D}|x|^{2\\alpha}\\exp({u(x)}) \\,\\rmd x}}\\quad in\\ D,\\tqs u(x)=0\\quad on\\ D.\\end{equation*} \\] In the case N = 1, 2, we provide necessary and sufficient conditions for the existence of blow up solutions and, in the spirit of Chen and Lin (2001 Ann. Inst. H. Poincaré. Anal. Non Linéare 18 271), prove their axial symmetry with respect to the diameter joining the maximum points. Finally, we prove that a non-radial one point blow up solution exists only if λ - 8π > 0.

  18. Film cooling effectiveness and heat transfer with injection through holes

    NASA Technical Reports Server (NTRS)

    Eriksen, V. L.

    1971-01-01

    An experimental investigation of the local film cooling effectiveness and heat transfer downstream of injection of air through discrete holes into a turbulent boundary layer of air on a flat plate is reported. Secondary air is injected through a single hole normal to the main flow and through both a single hole and a row of holes spaced at three diameter intervals with an injection angle of 35 deg to the main flow. Two values of the mainstream Reynolds number are used; the blowing rate is varied from 0.1 to 2.0. Photographs of a carbon dioxide-water fog injected into the main flow at an angle of 90 deg are also presented to show interaction between the jet and mainstream.

  19. Aflibercept Injection

    MedlinePlus

    ... injection is used to treat wet age-related macular degeneration (AMD; an ongoing disease of the eye that causes loss of the ability to see straight ahead and may make it more ... used to treat macular edema after retinal vein occlusion (an eye disease ...

  20. Cabazitaxel Injection

    MedlinePlus

    ... prednisone to treat prostate cancer (cancer of a male reproductive organ) that has already been treated with other medications. Cabazitaxel injection is in a class of medications called microtubule inhibitors. It works by slowing or stopping the growth of cancer cells.

  1. Hydrocortisone Injection

    MedlinePlus

    ... purple blotches or lines under the skin skin depressions at the injection site increased body fat or movement to different areas of your body difficulty falling asleep or staying asleep inappropriate happiness extreme ... increased sweating muscle weakness joint pain dizziness irregular ...

  2. Methylprednisolone Injection

    MedlinePlus

    ... purple blotches or lines under the skin skin depressions at the injection site increased body fat or movement to different areas of your body difficulty falling asleep or staying asleep inappropriate happiness extreme ... increased sweating muscle weakness joint pain dizziness irregular ...

  3. Triptorelin Injection

    MedlinePlus

    ... a sudden wave of mild or intense body heat) decreased sexual ability or desire leg or joint pain breast pain pain, itching, swelling, or redness at the place where injection was given difficulty falling asleep or staying asleep Some side effects can be serious. If you experience any of ...

  4. Eribulin Injection

    MedlinePlus

    ... tests to check your body's response to eribulin injection.It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring ...

  5. Pegaptanib Injection

    MedlinePlus

    ... to 7 days after you receive each pegaptanib injection.It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring ...

  6. Omalizumab Injection

    MedlinePlus

    ... and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: allergy shots (a series of injections given regularly to prevent the body from developing ...

  7. Famotidine Injection

    MedlinePlus

    ... treat ulcers (sores in the lining of the stomach or intestine) that were not successfully treated with other medications. ... Ellison syndrome (tumors in the pancreas and small intestine that caused increased production of stomach acid). Famotidine injection is in a class of ...

  8. Ranitidine Injection

    MedlinePlus

    ... treat ulcers (sores in the lining of the stomach or intestine) that were not successfully treated with other medications. ... Ellison syndrome (tumors in the pancreas and small intestine that caused increased production of stomach acid). Ranitidine injection is in a class of ...

  9. Oxytocin Injection

    MedlinePlus

    ... provider immediately: chest pain or difficulty breathing confusion fast or irregular heartbeat severe headache irritation at the injection site If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting ...

  10. Ganciclovir Injection

    MedlinePlus

    ... will be given to you two times a day for 2 to 3 weeks, and then once a day, 5 to 7 days of each week.Your dose of ganciclovir will ... may give you several doses (enough for a day's supply) of premixed ganciclovir injection solution at one ...

  11. Ibritumomab Injection

    MedlinePlus

    ... have received ibritumomab injection.do not have any vaccinations without talking to your doctor.you should know ... cells) and myelodysplastic syndrome (condition in which blood cells do not ... online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

  12. Tositumomab Injection

    MedlinePlus

    ... have received tositumomab injection.do not have any vaccinations without talking to your doctor.you should know ... blood cells), myelodysplastic syndrome (condition in which blood cells do not ... online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

  13. Dulaglutide Injection

    MedlinePlus

    ... other body tissues where it is used for energy. Dulaglutide injection also works by slowing the movement ... In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at ...

  14. Liraglutide Injection

    MedlinePlus

    ... other body tissues where it is used for energy. Liraglutide injection also slows the emptying of the ... In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at ...

  15. Albiglutide Injection

    MedlinePlus

    ... other body tissues where it is used for energy. Albiglutide injection also works by slowing the movement ... In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at ...

  16. Helicopter blade tip vortex modifications in hover using piezoelectrically modulated blowing

    NASA Astrophysics Data System (ADS)

    Vasilescu, Roxana

    Aeroacoustic investigations regarding different types of helicopter noise have indicated that the most annoying noise is caused by impulsive blade surface pressure changes in descent or forward flight conditions. Blade Vortex Interaction (BVI) is one of the main phenomena producing significant impulsive noise by the unsteady fluctuation in blade loading due to the rapid change of induced velocity field during interaction with vortices shed from previous blades. The tip vortex core structure and the blade vortex miss distance were identified as having a primary influence on BVI. In this thesis, piezoelectrically modulated and/or vectored blowing at the rotor blade tip is theoretically investigated as an active technique for modifying the structure of the tip vortex core as well as for increasing blade vortex miss distance. The mechanisms of formation and convection of rotor blade tip vortices up to and beyond 360 degrees wake age are described based on the CFD results for the baseline cases of a hovering rotor with rounded and square tips. A methodology combining electromechanical and CFD modeling is developed and applied to the study of a piezoelectrically modulated and vectored blowing two-dimensional wing section. The thesis is focused on the CFD analysis of rotor flow with modulated tangential blowing over a rounded blade tip, and with steady mid-plane blade tip blowing, respectively. Computational results characterizing the far-wake flow indicate that for steady tangential blowing the miss distance can be doubled compared to the baseline case, which may lead to a significant reduction in BVI noise level if this trend shown in hover can be replicated in low speed forward flight. Moreover, near-wake flow analysis show that through modulated blowing a higher dissipation of vorticity can be obtained.

  17. Reduction of Unsteady STATOR-ROTOR Interaction Using Trailing Edge Blowing

    NASA Astrophysics Data System (ADS)

    LEITCH, THOMAS A.; SAUNDERS, C. A.; NG, W. F.

    2000-08-01

    An aeroacoustic investigation was performed to assess the effects of adding mass flow at the trailing edges of stators upstream of an aircraft engine simulator. By using trailing edge blowing to minimize the shed wakes of the stators, the flow into the rotor was made more uniform, hence reducing the unsteady stator-rotor interaction. In these experiments, a reduced number of stators (four) was used in a 1/14 scale model inlet which was coupled to a 4·1in (10·4 cm) turbofan engine simulator. Steady state measurements of the aerodynamic flow field and acoustic far field were made in order to evaluate the aeroacoustic performance at three simulator speeds: 30k, 50k, and 70kr.p.m. The lowest test speed (30k r.p.m.) showed a noise reduction as large as 8·9dB in the blade passing tone. At 50k and 70kr.p.m., the reduction in blade passing tone was 5·5 and 2·6dB respectively. In addition, trailing edge blowing reduced the overall sound pressure level in every case. Aerodynamic measurements showed that fan face distortion was significantly reduced due to trailing edge blowing. The addition of trailing edge blowing from the four upstream stators did not change the operating point of the fan, and the mass flow added by the blowing was less than 1% of the fan mass flow rate. The results of these experiments clearly demonstrate that blowing from the trailing edges of the stators is effective in reducing unsteady stator-rotor interaction and the subsequent forward radiated noise.

  18. Evaluation of the Surface Roughness using AE method with Air Blowing

    NASA Astrophysics Data System (ADS)

    Yasuda, T.; Takata, S.; Hino, T.; Yoshida, K.

    2014-06-01

    This study aims to find the development for the evaluation of the surface roughness by the Acoustic Emission (AE) method with air blowing. We paid attention to the AE wave due to air blowing on the specimen plate with different surface roughness. The relationship between the AE wave and surface roughness of specimen plates was investigated. As the result, there is large and continuous difference in the Root Mean Square (RMS) value of their AE waveform. The RMS value decreases by increasing of the surface roughness of specimen plates. It suggested that this characteristic has the possibility to establish a new method of nondestructive surface roughness testing.

  19. Aerodynamic analysis of VTOL inlets and definition of a short, blowing-lip inlet

    NASA Technical Reports Server (NTRS)

    Syberg, J.; Jones, A. L.

    1982-01-01

    The results indicated that, without boundary layer control, either a very long inlet or an inlet with a very high contraction ratio lip will be required to meet the stringent design requirements. It is shown that active boundary layer control is an effective means of preventing separation and that a significant reduction in inlet size can be achieved by removing only a small amount of bleed in the throat region of the inlet. A short, blowing-lip model was designed and fabricated. This model features an adjustable, blowing slot located near the hilite on the windward side of the inlet.

  20. On the sublimation of blowing snow and of snow in canopies

    NASA Astrophysics Data System (ADS)

    Taylor, P. A.; Simon, K.; Gordon, M.; Weng, W.

    2003-04-01

    Tests have been made within the Canadian Land Surface Scheme (CLASS) of various parameterizations of sublimation of blowing snow, and tested in the context of data from weather stations (Goose Bay and Resolute) in northern Canada. We will focus on parameterization schemes based on results obtained with the PIEKTUK model of blowing snow. In addition we will present preliminary results concerning the parameterization of sublimation of snow caught in tree canopies, using schemes similar to those for evaporation from wet canopies. This is considered to be a major factor in the water budgets of forested areas in northern Canada.

  1. Noise Benefits of Rotor Trailing Edge Blowing for a Model Turbofan

    NASA Technical Reports Server (NTRS)

    Woodward, Richard P.; Fite, E. Brian; Podboy, Gary G.

    2007-01-01

    An advanced model turbofan was tested in the NASA Glenn 9- by 15-Foot Low Speed Wind Tunnel (9x15 LSWT) to explore far field acoustic effects associated with rotor Trailing-Edge-Blowing (TEB) for a modern, 1.294 stage pressure ratio turbofan model. The TEB rotor (Fan9) was designed to be aerodynamically similar to the previously tested Fan1, and used the same stator and nacelle hardware. Fan9 was designed with trailing edge blowing slots using an external air supply directed through the rotor hub. The TEB flow was heated to approximate the average fan exit temperature at each fan test speed. Rotor root blockage inserts were used to block TEB to all but the outer 40 and 20% span in addition to full-span blowing. A configuration with full-span TEB on alternate rotor blades was also tested. Far field acoustic data were taken at takeoff/approach conditions at 0.10 tunnel Mach. Far-field acoustic results showed that full-span blowing near 2.0% of the total flow could reduce the overall sound power level by about 2 dB. This noise reduction was observed in both the rotor-stator interaction tones and for the spectral broadband noise levels. Blowing only the outer span region was not very effective for lowering noise, and actually increased the far field noise level in some instances. Full-span blowing of alternate blades at 1.0% of the overall flow rate (equivalent to full-span blowing of all blades at 2.0% flow) showed a more modest noise decrease relative to full-span blowing of all blades. Detailed hot film measurements of the TEB rotor wake at 2.0% flow showed that TEB was not every effective for filling in the wake defect at approach fan speed toward the tip region, but did result in overfilling the wake toward the hub. Downstream turbulence measurements supported this finding, and support the observed reduction in spectral broadband noise.

  2. Blow-up conditions for two dimensional modified Euler-Poisson equations

    NASA Astrophysics Data System (ADS)

    Lee, Yongki

    2016-09-01

    The multi-dimensional Euler-Poisson system describes the dynamic behavior of many important physical flows, yet as a hyperbolic system its solution can blow-up for some initial configurations. This article strives to advance our understanding on the critical threshold phenomena through the study of a two-dimensional modified Euler-Poisson system with a modified Riesz transform where the singularity at the origin is removed. We identify upper-thresholds for finite time blow-up of solutions for the modified Euler-Poisson equations with attractive/repulsive forcing.

  3. Huge "Superbubble" of Gas Blowing Out of Milky Way

    NASA Astrophysics Data System (ADS)

    2006-01-01

    out of the plane has to have been unusually violent," he added. The scientists speculate that the gas may be blown outward by the strong stellar winds and supernova explosions from numerous massive young stars in a cluster. "One theoretical model shows that young stars could power an outflow that matches what we see very closely," Pidopryhora said. According to that model, the superbubble probably is 10-30 million years old. "Finding this superbubble practically in our back yard is quite exciting, because these superbubbles are very important factors in how galaxies evolve," Lockman said. Superbubbles, powered by supernova explosions and young stellar winds, control the way heavy elements, produced only in the cores of stars, are distributed throughout the galaxy, the scientists said. Those heavy elements are then incorporated into the next generation of stars -- and planets -- to form. "The formation of our own Sun and planets probably was heavily influenced, if not triggered, by a nearby supernova explosion," Lockman said. In addition, if the outflow from superbubbles is energetic enough, it could blow the gas into intergalactic space, never to return to the galaxy. "This would shut down the formation of new stars in the galaxy," Pidopryhora explained. The Green Bank Telescope, dedicated in 2000, is the largest fully-steerable radio telescope in the world, with more than two acres of collecting area in its giant dish. Located within the National Radio Quiet Zone in West Virginia, the GBT provides extraordinary sensitivity for observing faint radio-emitting objects in the distant Universe. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

  4. How to Blow a Bubble in a Galaxy

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-10-01

    outflow from a startburst concentrated near the nuclei. Either of these outflows could blow a bubble as it first interacts with the interstellar medium.The authors show that the first category is disfavored based on observational and energetics arguments. In addition, the western-most nucleus and the bubble both align exactly with the axis of the large-scale outflows of the galaxy. Unlikely to be due to chance, this alignment is strong support in favor of the second category.Thus, its probable that the bubble is blown by an outflow that originates from the inner ~100pc around one of the nuclei, either due to a jet or a starburst wind. Further observations should be able to differentiate between these two mechanisms.CitationKelly E. Lockhart et al 2015 ApJ 810 149. doi:10.1088/0004-637X/810/2/149

  5. Research and Analysis on the Physical and Chemical Properties of Molten Bath with Bottom-Blowing in EAF Steelmaking Process

    NASA Astrophysics Data System (ADS)

    Wei, Guangsheng; Zhu, Rong; Dong, Kai; Ma, Guohong; Cheng, Ting

    2016-06-01

    Bottom-blowing technology is widely adopted in electric arc furnace (EAF) steelmaking to promote the molten bath fluid flow, accelerate the metallurgical reaction, and improve the quality of molten steel. In this study, a water model experiment and a computational fluid dynamics model were established to investigate the effects of bottom-blowing gas flow rate on the fluid flow characteristics in the EAF molten bath. The results show that the interaction among the bottom-blowing gas streams influences the molten bath flow field, and increasing the bottom-blowing gas flow rate can accelerate the fluid flow and decrease the volume of the dead zone. Based on industrial application research, the physical and chemical properties of the molten bath with bottom-blowing were analyzed. Compared with traditional melting conditions without bottom-blowing, bottom-blowing technology demonstrates obvious advantages in promoting the heat transfer and metallurgical reactions in the molten bath. With the bottom-blowing arrangement, the dephosphorization and decarburization rates are accelerated, the contents of FeO and T. Fe in endpoint slag are decreased, and the endpoint carbon-oxygen equilibrium of molten steel is improved.

  6. MHD heat and mass transfer flow over a permeable stretching/shrinking sheet with radiation effect

    NASA Astrophysics Data System (ADS)

    Mat Yasin, Mohd Hafizi; Ishak, Anuar; Pop, Ioan

    2016-06-01

    The steady two-dimensional magnetohydrodynamic (MHD) flow past a permeable stretching/shrinking sheet with radiation effects is investigated. The similarity transformation is introduced to transform the governing partial differential equations into a system of ordinary differential equations before being solved numerically using a shooting method. The results are obtained for the skin friction coefficient, the local Nusselt number and the local Sherwood number as well as the velocity, temperature and the concentration profiles for some values of the governing parameters, namely, suction/injection parameter S, stretching/shrinking parameter λ, magnetic parameter M, radiation parameter R, heat source/sink Q and chemical rate parameter K. For the shrinking case, there exist two solutions for a certain range of parameters, but the solution is unique for the stretching case. The stability analysis verified that the upper branch solution is linearly stable and physically reliable while the lower branch solution is not. For the reliable solution, the skin friction coefficient increases in the present of magnetic field. The heat transfer rate at the surface decreases in the present of radiation.

  7. An ESL Instructor's Perspective on the Stretch Program.

    ERIC Educational Resources Information Center

    Todorovska, Viktorija

    Stretch 107 is a version of English 107 (a first-year composition course for international students at Arizona State University), designed to provide those with low proficiency in English with various strategies for writing acceptable prose in English. Since it is a 2-semester course, Stretch 107 gives students more time to work on their…

  8. Does Postexercise Static Stretching Alleviate Delayed Muscle Soreness?

    ERIC Educational Resources Information Center

    Buroker, Katherine C.; Schwane, James A.

    1989-01-01

    Because many experts recommend stretching after exercise to relieve muscle soreness, 23 subjects performed a 30-minute step test to induce delayed muscle soreness. There was neither temporary relief of pain immediately after stretching nor a reduction in pain during the 3-day postexercise period. (Author/SM)

  9. Cyclic stretch of airway epithelium inhibits prostanoid synthesis.

    PubMed

    Savla, U; Sporn, P H; Waters, C M

    1997-11-01

    Airway epithelial cells (AEC) metabolize arachidonic acid (AA) to biologically active eicosanoids, which contribute to regulation of airway smooth muscle tone and inflammatory responses. Although in vivo the airways undergo cyclical stretching during ventilation, the effect of cyclic stretch on airway epithelial AA metabolism is unknown. In this study, cat and human AEC were grown on flexible membranes and were subjected to cyclic stretch using the Flexercell strain unit. Cyclic stretch downregulated synthesis of prostaglandin (PG) E2, PGI2, and thromboxane A2 by both cell types in a frequency-dependent manner. The percent inhibition of prostanoid synthesis in both cell types ranged from 53 +/- 7 to 75 +/- 8% (SE; n = 4 and 5, respectively). Treatment of cat AEC with exogenous AA (10 micrograms/ml) had no effect on the stretch-induced inhibition of PGE2 synthesis, whereas treatment with exogenous PGH2 (10 micrograms/ml) overcame the stretch-induced decrease in PGE2 production. These results indicate that stretch inhibits prostanoid synthesis by inactivating cyclooxygenase. When cells were pretreated with the antioxidants catalase (100 micrograms/ml, 150 U/ml) and N-acetylcysteine (1 mM), there was a partial recovery of eicosanoid production, suggesting that cyclic stretch-induced inactivation of cyclooxygenase is oxidant mediated. These results may have important implications for inflammatory diseases in which airway mechanics are altered. PMID:9374729

  10. A Stretching Device for High Resolution Live-Cell Imaging

    PubMed Central

    Huang, Lawrence; Mathieu, Pattie S.; Helmke, Brian P.

    2012-01-01

    Several custom-built and commercially available devices are available to investigate cellular responses to substrate strain. However, analysis of structural dynamics by microscopy in living cells during stretch is not readily feasible. We describe a novel stretch device optimized for high-resolution live-cell imaging. The unit assembles onto standard inverted microscopes and applies constant magnitude or cyclic stretch at physiological magnitudes to cultured cells on elastic membranes. Interchangeable modular indenters enable delivery of equibiaxial and uniaxial stretch profiles. Strain analysis performed by tracking fluorescent microspheres adhered onto the substrate demonstrated reproducible application of stretch profiles. In endothelial cells transiently expressing EGFP-vimentin and paxillin-DsRed2 and subjected to constant magnitude equibiaxial stretch, the 2-D strain tensor demonstrated efficient transmission through the extracellular matrix and focal adhesions. Decreased transmission to the intermediate filament network was measured, and a heterogeneous spatial distribution of maximum stretch magnitude revealed discrete sites of strain focusing. Spatial correlation of vimentin and paxillin displacement vectors provided an estimate of the extent of mechanical coupling between the structures. Interestingly, switching the spatial profile of substrate strain reveals that actin-mediated edge ruffling is not desensitized to repeated mechano-stimulation. These initial observations show that the stretch device is compatible with live-cell microscopy and is a novel tool for measuring dynamic structural remodeling under mechanical strain. PMID:20195762

  11. Identification of CFC and HCFC substitutes for blowing polyurethane foam insulation products. Final report, September 1993-November 1994

    SciTech Connect

    Howard, P.H.; Tunkel, J.L.; Banerjee, S.

    1995-10-01

    The report gives results of a cooperative effort to identify chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) substitutes for blowing polyurethane foam insulation products. More than 100 chemicals have been identified and ranked as polyurethane foam blowing agent candidates. The systematic investigation involved the analysis of vapor thermal conductivity predictive models and utilizing this methodology to identify and screen potential new foam blowing agents. Collection of physical/chemical properties of the new candidates enabled an overall evaluation. Based on the vapor thermal conductivity, boiling point, and other important properties, the chemical compounds were ranked to identify the most promising new blowing agent candidates. To efficiently evaluate new foam blowing agents, the compounds were placed and evaluated in 14 groups based on chemical structure.

  12. Experimental investigation of tangential blowing for control of the strong shock boundary layer interaction on inlet ramps

    NASA Technical Reports Server (NTRS)

    Schwendemann, M. F.

    1981-01-01

    A 0.165-scale isolated inlet model was tested in the NASA Lewis Research Center 8-ft by 6-ft Supersonic Wind Tunnel. Ramp boundary layer control was provided by tangential blowing from a row of holes in an aft-facing step set into the ramp surface. Testing was performed at Mach numbers from 1.36 to 1.96 using both cold and heated air in the blowing system. Stable inlet flow was achieved at all Mach numbers. Blowing hole geometry was found to be significant at 1.96M. Blowing air temperature was found to have only a small effect on system performance. High blowing levels were required at the most severe test conditions.

  13. Dielectrophoretic stretching of DNA tethered to a fiber tip

    NASA Astrophysics Data System (ADS)

    Hyun, Changbae; Kaur, Harpreet; McNabb, David S.; Li, Jiali

    2015-03-01

    In this work, we studied the stretching of λ phage DNA molecules immobilized on an optical fiber tip attached to a force sensitive tuning fork under ac electric fields. We designed a two electrodes stretching system in a small chamber: one is a gold-coated optical fiber tip electrode, and the other is a gold-coated flat electrode. By applying a dielectrophoretic (DEP) force, the immobilized λ DNA molecules on the tip are stretched and the stretching process is monitored by a fluorescent microscope. The DNA stretching in three-dimensional space is optimized by varying electrode shape, electrode gap distance, ac frequency, and solution conductivity. By observing the vibrational amplitude change of a quartz tuning fork, we measured the effects due to Joule heating and the DEP force on the tethered DNA molecules in solution. This work demonstrates a method to manipulate and characterize immobilized λ DNA molecules on a probe tip for further study of single DNA molecules.

  14. Dielectrophoretic Stretching of DNA Tethered to a Fiber Tip

    PubMed Central

    Hyun, Changbae; Kaur, Harpreet; McNabb, David S.; Li, Jiali

    2015-01-01

    In this work, we studied the stretching of λ phage DNA molecules immobilized on an optical fiber tip attached to a force sensitive tuning fork under AC electric fields. We designed a two electrodes stretching system in a small chamber: one is a gold-coated optical fiber tip electrode, and the other is a gold-coated flat electrode. By applying a dielectrophoretic force, the immobilized λ DNA molecules on the tip are stretched and the stretching process is monitored by a fluorescent microscope. The DNA stretching in three-dimensional space is optimized by varying electrode shape, electrode gap distance, AC frequency, and solution conductivity. By observing the vibrational amplitude change of a quartz tuning fork, we measured the effects due to Joule heating and the dielectrophoretic force on the tethered DNA molecules in solution. This work demonstrates a method to manipulate and characterize immobilized λ DNA molecules on a probe tip for further study of single DNA molecules. PMID:25741602

  15. Stretched Lens Array Squarerigger (SLASR) Technology Maturation

    NASA Technical Reports Server (NTRS)

    O'Neill, Mark; McDanal, A.J.; Howell, Joe; Lollar, Louis; Carrington, Connie; Hoppe, David; Piszczor, Michael; Suszuki, Nantel; Eskenazi, Michael; Aiken, Dan; Fulton, Michael; Brandhorst, Henry; Schuller, Michael

    2007-01-01

    Since April 2005, our team has been underway on a competitively awarded program sponsored by NASA s Exploration Systems Mission Directorate to develop, refine, and mature the unique solar array technology known as Stretched Lens Array SquareRigger (SLASR). SLASR offers an unprecedented portfolio of performance metrics, SLASR offers an unprecedented portfolio of performance metrics, including the following: Areal Power Density = 300 W/m2 (2005) - 400 W/m2 (2008 Target) Specific Power = 300 W/kg (2005) - 500 W/kg (2008 Target) for a Full 100 kW Solar Array Stowed Power = 80 kW/cu m (2005) - 120 kW/m3 (2008 Target) for a Full 100 kW Solar Array Scalable Array Capacity = 100 s of W s to 100 s of kW s Super-Insulated Small Cell Circuit = High-Voltage (300-600 V) Operation at Low Mass Penalty Super-Shielded Small Cell Circuit = Excellent Radiation Hardness at Low Mass Penalty 85% Cell Area Savings = 75% Lower Array Cost per Watt than One-Sun Array Modular, Scalable, & Mass-Producible at MW s per Year Using Existing Processes and Capacities

  16. Single, stretched membrane, structural module experiments

    SciTech Connect

    Wood, R.L.

    1986-02-01

    This report describes tests done on stretched-membrane heliostats used to reflect solar radiation onto a central receiver. The tests were used to validate prior analysis and mathematical models developed to describe module performance. The modules tested were three meters in diameter and had reflective polymer film laminated to the membrane. The frames were supported at three points equally spaced around the ring. Three modules were pneumatically attached with their weight suspended at the bottom support, two were pneumatically attached with their weight suspended from the upper mounts, and one was rigidly attached with its weight suspended at the bottom mount. By varying the membrane tension we could simulate a uniform wind loading normal to the mirror's surface. A video camera 15+ meters away from the mirror recorded the virtual image of a target grid as reflected by the mirrors' surface. The image was digitized and stored on a microcomputer. Using the law of reflection and analytic geometry, we computed the surface slopes of a sampling of points on the surface. The dominant module response was consistent with prior SERI analyses. The simple analytical model is quite adequate for designing and sizing single-membrane modules if the initial imperfections and their amplification are appropriately controlled. To avoid potential problems resulting from the fundamentally n = 2 deformation phenomena, we advise using either relatively stiffer ring frames or more than three support points.

  17. Reflectors Made from Membranes Stretched Between Beams

    NASA Technical Reports Server (NTRS)

    Dooley, Jennifer; Dragovan, Mark; Tolomeo, Jason

    2009-01-01

    Lightweight cylindrical reflectors of a proposed type would be made from reflective membranes stretched between pairs of identically curved and identically oriented end rails. In each such reflector, the curvature of the two beams would define the reflector shape required for the intended application. For example, the beams could be curved to define a reflector of parabolic cross section, so that light incident along the axis of symmetry perpendicular to the cylindrical axis would be focused to a line. In addition, by applying suitable forces to the ends of the beams, one could bend the beams to adjust the reflector surface figure to within a precision of the order of the wavelength of the radiation to be reflected. The figure depicts an example of beams shaped so that in the absence of applied forces, each would be flat on one side and would have a radius of curvature R on the opposite side. Alternatively, the curvature of the reflector-membrane side could be other than circular. In general, the initial curvature would be chosen to optimize the final reflector shape. Then by applying forces F between the beam ends in the positions and orientations shown in the figure, one could bend beams to adjust their shape to a closer approximation of the desired precise circular or noncircular curvature.

  18. Streptomycin inhibits electrophysiological changes induced by stretching of chronically infarcted rat hearts*

    PubMed Central

    Cao, Jun-xian; Fu, Lu; Gao, Qian-ping; Xie, Rong-sheng; Qu, Fan

    2014-01-01

    Objective: To investigate stretch-induced electrophysiological changes in chronically infarcted hearts and the effect of streptomycin (SM) on these changes in vivo. Methods: Sixty Wistar rats were divided randomly into four groups: a control group (n=15), an SM group (n=15), a myocardial infarction (MI) group (n=15), and an MI+SM group (n=15). Chronic MI was obtained by ligating the left anterior descending branch (LAD) of rat hearts for eight weeks. The in vivo blockade of stretch-activated ion channels (SACs) was achieved by intramuscular injection of SM (180 mg/(kg∙d)) for seven days after operation. The hearts were stretched for 5 s by occlusion of the aortic arch. Suction electrodes were placed on the anterior wall of left ventricle to record the monophasic action potential (MAP). The effect of stretching was examined by assessing the 90% monophasic action potential duration (MAPD90), premature ventricular beats (PVBs), and ventricular tachycardia (VT). Results: The MAPD90 decreased during stretching in both the control (from (50.27±5.61) ms to (46.27±4.51) ms, P<0.05) and MI groups (from (65.47±6.38) ms to (57.47±5.76 ms), P<0.01). SM inhibited the decrease in MAPD90 during inflation ((46.27±4.51) ms vs. (49.53±3.52) ms, P<0.05 in normal hearts; (57.47±5.76) ms vs. (61.87±5.33) ms, P<0.05 in MI hearts). The occurrence of PVBs and VT in the MI group increased compared with that in the control group (PVB: 7.93±1.66 vs. 1.80±0.86, P<0.01; VT: 7 vs. 1, P<0.05). SM decreased the occurrence of PVBs in both normal and MI hearts (0.93±0.59 vs. 1.80±0.86 in normal hearts, P<0.05; 5.40±1.18 vs. 7.93±1.66 in MI hearts, P<0.01). Conclusions: Stretch-induced MAPD90 changes and arrhythmias were observed in chronically infarcted myocardium. The use of SM in vivo decreased the incidence of PVBs but not of VT. This suggests that SACs may be involved in mechanoelectric feedback (MEF), but that there might be other mechanisms involved in causing VT in chronic MI

  19. Some Aspects of the Interaction of Blowing Snow with the Atmospheric Boundary Layer

    NASA Astrophysics Data System (ADS)

    Déry, Stephen J.; Taylor, Peter A.

    1996-10-01

    Several possible effects of blowing snow on the atmospheric boundary layer are investigated, mostly within the general framework of the Prairie Blowing Snow Model (PBSM). The processes of snow saltation and suspension are first described. Variations to the drift density profile are tested and the effects of stratification and density variation calculations are evaluated. Despite high density gradients of blowing snow, stratification effects on turbulence and the velocity profiles can generally be neglected. However, with saltating or suspended snow in a constant shear stress layer, part of the shear stress is carried by the particles. A highly simplified, single-phase approach, based on the density variation of the air-snow mixture coupled to a simple turbulent stress-strain relationship, is used to illustrate this. Sublimation rates in a column of blowing snow are calculated using the PBSM and results are compared with those obtained with a modified formulation which incorporates a spectrum of sublimating particles of varying sizes at each height in a steady-state surface boundary layer and different specifications of the ventilation velocity.

  20. EVALUATION OF HFC 245CA AND HFC 236EA AS FOAM BLOWING AGENTS

    EPA Science Inventory

    The paper gives results of a limited evaluation of the developmental hydrofluorocarbons (HFCS) 245ca and 236ea as blowing agents in urethane-based insulation. hese materials were selected from screening tests of 37 C2, C3, and C4 isomers based on physical properties, atmospheric ...