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Sample records for high response injection

  1. High strain-rate response of injectable PAA hydrogel.

    PubMed

    Lin, Hong-Ru; Wang, Shih-Han; Chiang, Chia-Chin; Juang, Yun-Ching; Yu, Fu-Ann; Tsai, Liren

    2015-01-01

    Hydrogel materials have been widely considered as potential soft tissue replacements because of their high permeability, hydrophilicity, and biocompatibility, as well as their low coefficient of friction. Injectable (thermo-responsive) hydrogels can provide support and cushioning at irregularly shaped disease sites, and are thus suitable for use in treating osteoarthritis or degenerative disc disease. However, while some injectable hydrogels have been proven to sustain human body weight during daily activities, their mechanical properties under harsh dynamic conditions have not been well documented. A specified injectable polyacrylic acid (PAA) hydrogel was prepared for this study. To simulate sudden impacts or unexpected shocks to the PAA hydrogel, the split Hopkinson pressure bar technique was utilized. The dynamic responses of various hydrogels at confined high strain rates (100-2590 s(-1)) were presented. Hydrogel specimens with 3.37, 6.75, and 13.5% acrylic acid (AAc) concentrations were tested in the following three different material conditions: raw, phosphate-buffered saline (PBS) swollen, and PBS swollen with elevated temperature (37 °C). The dynamic bulk moduli of the hydrogels varied from 1.55 to 47.8 MPa depending on the given hydrogel's AAc concentration and swollen condition. PMID:25816201

  2. A harmonic injection SPWM method for the high-responsive PMSM control system

    NASA Astrophysics Data System (ADS)

    Lei, Wang; Shuanghui, Hao; Minghui, Hao; Baoyu, Song

    2016-01-01

    In a permanent magnet synchronous motor (PMSM) control system, usually, the phase voltage instruction is limited independently to prevent a three-phase pulse width modulation (PWM) wave from overflowing. This method decreases the efficiency of the bus voltage and causes voltage vector direction errors. To solve these problems, we propose a harmonic injection sinusoidal pulse-width modulation (SPWM). This method uses harmonic injected sinusoidal PWM to improve the utilisation ratio of the bus voltage, and consequently improve system performance. In this paper, we analyse the problem in terms of potential difference. The simulation results show that the proposed method can increase the utilisation ratio of the bus voltage up to 15.4%, and the voltage vector mode obtained with the proposed algorithm is larger than that obtained with the conventional one. The method with harmonic injection consequently improves current response, without affecting voltage vector accuracy. The experiment results validate the proposed method.

  3. Quasi-Static and High Strain Rate Compressive Response of Injection-Molded Cenosphere/HDPE Syntactic Foam

    NASA Astrophysics Data System (ADS)

    Bharath Kumar, B. R.; Singh, Ashish Kumar; Doddamani, Mrityunjay; Luong, Dung D.; Gupta, Nikhil

    2016-07-01

    High strain rate compressive properties of high-density polyethylene (HDPE) matrix syntactic foams containing cenosphere filler are investigated. Thermoplastic matrix syntactic foams have not been studied extensively for high strain rate deformation response despite interest in them for lightweight underwater vehicle structures and consumer products. Quasi-static compression tests are conducted at 10-4 s-1, 10-3 s-1 and 10-2 s-1 strain rates. Further, a split-Hopkinson pressure bar is utilized for characterizing syntactic foams for high strain rate compression. The compressive strength of syntactic foams is higher than that of HDPE resin at the same strain rate. Yield strength shows an increasing trend with strain rate. The average yield strength values at high strain rates are almost twice the values obtained at 10-4 s-1 for HDPE resin and syntactic foams. Theoretical models are used to estimate the effectiveness of cenospheres in reinforcing syntactic foams.

  4. Quasi-Static and High Strain Rate Compressive Response of Injection-Molded Cenosphere/HDPE Syntactic Foam

    NASA Astrophysics Data System (ADS)

    Bharath Kumar, B. R.; Singh, Ashish Kumar; Doddamani, Mrityunjay; Luong, Dung D.; Gupta, Nikhil

    2016-04-01

    High strain rate compressive properties of high-density polyethylene (HDPE) matrix syntactic foams containing cenosphere filler are investigated. Thermoplastic matrix syntactic foams have not been studied extensively for high strain rate deformation response despite interest in them for lightweight underwater vehicle structures and consumer products. Quasi-static compression tests are conducted at 10-4 s-1, 10-3 s-1 and 10-2 s-1 strain rates. Further, a split-Hopkinson pressure bar is utilized for characterizing syntactic foams for high strain rate compression. The compressive strength of syntactic foams is higher than that of HDPE resin at the same strain rate. Yield strength shows an increasing trend with strain rate. The average yield strength values at high strain rates are almost twice the values obtained at 10-4 s-1 for HDPE resin and syntactic foams. Theoretical models are used to estimate the effectiveness of cenospheres in reinforcing syntactic foams.

  5. High-pressure Injection Injuries of the Hand.

    PubMed

    Cannon, Tyler A

    2016-07-01

    High-pressure injection hand injuries are often overlooked, with severe complications owing to the acute inflammatory response. Prognosis for depends on the type of material injected, location of injection, involved pressure, and timing to surgical decompression and debridement. Acute management involves broad-spectrum antibiotics, tetanus prophylaxis, emergent decompression within 6 hours, and complete removal of the injected material. Most patients have residual sequelae of stiffness, pain, sensation loss, and difficulties in returning to work. The hand surgeon's role is prompt surgical intervention, early postoperative motion, and education of patient and staff regarding short- and long-term expectations. PMID:27241384

  6. High injection vs low injection behaviour of solar cells

    SciTech Connect

    Luque, A.; Araujo, G.L.; Calleja, M.J.

    1984-05-01

    An unitary model similar to the Ebers Moll one is presented to describe the behaviour of BSF cells working under either high or low injection. The model is applied to bifacial cells. The influence of the base resistivity on the front to back illumination short-circuit current is explained, as well as the cross-over presented by the I-V curve under front and back illuminations.

  7. Arctic stratospheric sulphur injections: radiative forcings and cloud responses

    NASA Astrophysics Data System (ADS)

    Lohmann, U.; Gasparini, B.; Miriam, K.; Kravitz, B.; Rasch, P. J.

    2014-12-01

    Observations and climate projections show a high sensitivity of the Arctic climate to the increase in greenhouse gas emissions, known as the polar amplification. This study evaluates the options of counteracting the rising polar temperatures by stratospheric sulphur injections in the Northern Hemisphere high latitudes.10 Mt of sulphur dioxide are emitted in a point emission source setup centred at the 100 hPa pressure level over Svalbard island (80°N,15°E). We perform simulations with the general circulation models ECHAM5, ECHAM6, and GISS ModelE. We study pulsed emission simulations that differ among themselves by the injection starting date (March-September), injection length (1, 30, or 90 day emission period), and the vertical resolution of the model (for ECHAM6). We find injections in April to be the most efficient in terms of the shortwave radiative forcing at the top-of-the atmosphere over the Arctic region. The distribution of sulphate aerosol spreads out beyond the injection region, with a significant share reaching the Southern Hemisphere. Results from ModelE show high latitude injections could counteract the spring and summer temperature increase due to higher atmospheric CO2 concentrations. Preliminary results with a more realistic description of clouds in ECHAM-HAM reveal a complex pattern of responses, most notably: a decrease in Northern Hemisphere cirrus clouds strengthening the effect of stratospheric aerosols in ECHAM5 a decrease in low-level clouds over the Arctic increasing the incoming solar radiation and causing a net positive radiative balance cirrus clouds are resilient to stratospheric sulphur injections in the absence of sulphate warming

  8. High productivity injection practices at Rouge Steel

    SciTech Connect

    Barker, D.H.; Hegler, G.L.; Falls, C.E.

    1995-12-01

    Rouge Steel Company, located in Dearborn, Michigan, operates two blast furnaces. The smaller of the pair, ``B`` Furnace, has a hearth diameter of 20 feet and 12 tuyeres. It has averaged 2,290 NTHM (net ton of hot metal) per day of 8.2 NTHM per 100 cubic feet of working volume. ``C`` Furnace has a hearth diameter of 29 feet and 20 tuyeres. Both of these furnaces are single tap hole furnaces. Prior to its reline in 1991, ``C`` Furnace was producing at a rate of 3,300 NTHM/day or about 6.25 NTHM/100 cfwv. In November, 1994 it averaged 5,106 NTHM/day or 9.6 NTHM/100 cfwv. This paper discusses how the current production rates were achieved. Also, the areas that needed to be addressed as production increased will be described. These areas include casthouse arrangement and workload, hot metal ladle capacity, slag pot capacity and charging capability. Coupled with the high blast temperature capability, the furnace was provided with a new natural gas injection system that injected the gas through the blowpipes and a natural gas injection system to enrich the stove gas. Following the furnace reline, natural gas has been used in three ways: tuyere level control; combination injection; and stove gas enrichment. Coke consumption rate has also decreased per NTHM.

  9. Influence of temperature, needle gauge and injection rate on the size distribution, concentration and acoustic responses of ultrasound contrast agents at high frequency.

    PubMed

    Sun, Chao; Panagakou, Ioanna; Sboros, Vassilis; Butler, Mairead B; Kenwright, David; Thomson, Adrian J W; Moran, Carmel M

    2016-08-01

    This paper investigated the influence of needle gauge (19G and 27G), injection rate (0.85ml·min(-1), 3ml·min(-1)) and temperature (room temperature (RT) and body temperature (BT)) on the mean diameter, concentration, acoustic attenuation, contrast to tissue ratio (CTR) and normalised subharmonic intensity (NSI) of three ultrasound contrast agents (UCAs): Definity, SonoVue and MicroMarker (untargeted). A broadband substitution technique was used to acquire the acoustic properties over the frequency range 17-31MHz with a preclinical ultrasound scanner Vevo770 (Visualsonics, Canada). Significant differences (P<0.001-P<0.05) between typical in vitro setting (19G needle, 3ml·min(-1) at RT) and typical in vivo setting (27G needle, 0.85ml·min(-1) at BT) were found for SonoVue and MicroMarker. Moreover we found that the mean volume-based diameter and concentration of both SonoVue and Definity reduced significantly when changing from typical in vitro to in vivo experimental set-ups, while those for MicroMarker did not significantly change. From our limited measurements of Definity, we found no significant change in attenuation, CTR and NSI with needle gauge. For SonoVue, all the measured acoustic properties (attenuation, CTR and NSI) reduced significantly when changing from typical in vitro to in vivo experimental conditions, while for MicroMarker, only the NSI reduced, with attenuation and CTR increasing significantly. These differences suggest that changes in physical compression and temperature are likely to alter the shell structure of the UCAs resulting in measureable and significant changes in the physical and high frequency acoustical properties of the contrast agents under typical in vitro and preclinical in vivo experimental conditions. PMID:27140502

  10. Discharge characteristics of a high speed fuel injection system

    NASA Technical Reports Server (NTRS)

    Matthews, Robertson

    1925-01-01

    Discussed here are some discharge characteristics of a fuel injection system intended primarily for high speed service. The system consisted of a cam actuated fuel pump, a spring loaded automatic injection valve, and a connecting tube.

  11. Injection molding ceramics to high green densities

    NASA Technical Reports Server (NTRS)

    Mangels, J. A.; Williams, R. M.

    1983-01-01

    The injection molding behavior of a concentrated suspension of Si powder in wax was studied. It was found that the injection molding behavior was a function of the processing techniques used to generate the powder. Dry ball-milled powders had the best molding behavior, while air classified and impact-milled powders demonstrated poorer injection moldability. The relative viscosity of these molding batches was studied as a function of powder properties: distribution shape, surface area, packing density, and particle morphology. The experimental behavior, in all cases, followed existing theories. The relative viscosity of an injection molding composition composed of dry ball-milled powders could be expressed using Farris' relation.

  12. Microbial Response to Carbon Dioxide Injection in a Shallow Aquifer

    NASA Astrophysics Data System (ADS)

    Rook, A.; Faehndrich, D.; O'Mullan, G.; Mailloux, B.; Matter, J.; Stute, M.; Goldberg, D.

    2007-12-01

    Extensive research is underway to investigate the geophysical and geochemical dynamics of subsurface carbon sequestration, but there has been only theoretical consideration of the microbial response. Microbial dynamics are capable of altering the range and rates of geochemical reactions in the subsurface. The goal of this field experiment is to link geochemical changes due to CO2 injection to alterations in the microbial community and to provide an initial characterization of the microbial response. A seven week push-pull experiment was conducted at the Lamont-Doherty Earth Observatory Test Well. 200L of groundwater was extracted, bubbled with carbon dioxide, augmented with a bromide tracer, and injected to 230m depth below ground surface. The hydraulically isolated injection zone marked the contact area between dolerite sill and sedimentary rock. Samples were taken on a weekly basis. Geochemically, a drop in pH from 9.4 to 4.5 at injection was coupled with a release of Fe2+ from the formation. As neutralization and mixing caused pH to return toward background levels, Fe2+ concentrations decreased. The aquifer remained anoxic throughout the experiment. DNA was successfully extracted and the gene encoding 16S ribosomal RNA was amplified from all samples with the exception of the injection fluid. Sequencing from clone libraries and tRFLP analyses were used to characterize microbial dynamics during the seven week study. Whereas the number of microbial groups detected remained relatively constant over the course of the experiment, changes were observed in both the dominant microbes phylogenetic identity and relative abundance. Methane concentrations increased from background levels (below 50 nM) to 4.2 nM after injection, but initial attempts to amplify archaeal and methanogen-specific genes were unsuccessful, bringing into question the presence of a significant methanogenic population. These results confirm that there is a microbial response to carbon dioxide

  13. Injectable, porous, and cell-responsive gelatin cryogels

    PubMed Central

    Koshy, Sandeep T.; Ferrante, Thomas C.; Lewin, Sarah A.; Mooney, David J.

    2014-01-01

    The performance of biomaterials-based therapies can be hindered by complications associated with surgical implant, motivating the development of materials systems that allow minimally invasive introduction into the host. In this study, we created cell-adhesive and degradable gelatin scaffolds that could be injected through a conventional needle while maintaining a predefined geometry and architecture. These scaffolds supported attachment, proliferation, and survival of cells in vitro and could be degraded by recombinant matrix metalloproteinase-2 and -9. Prefabricated gelatin cryogels rapidly reassumed their original shape when injected subcutaneously into mice and elicited only a minor host response following injection. Controlled release of granulocyte-macrophage colony-stimulating factor from gelatin cryogels resulted in complete infiltration of the scaffold by immune cells and promoted matrix metalloproteinase production leading to cell-mediated degradation of the cryogel matrix. These findings suggest that gelatin cryogels could serve as a cell-responsive platform for biomaterial-based therapy. PMID:24345735

  14. A high-altitude barium radial injection experiment

    NASA Technical Reports Server (NTRS)

    Wescott, E. M.; Stenbaek-Nielsen, H. C.; Hallinan, T. J.; Deehr, C. S.; Romick, G. J.; Olson, J. V.; Roederer, J. G.; Sydora, R.

    1980-01-01

    A rocket launched from Poker Flat, Alaska, carried a new type of high-explosive barium shaped charge to 571 km, where detonation injected a thin disk of barium vapor with high velocity nearly perpendicular to the magnetic field. The TV images of the injection are spectacular, revealing three major regimes of expanding plasma which showed early instabilities in the neutral gas. The most unusual effect of the injection is a peculiar rayed barium-ion structure lying in the injection plane and centered on a 5 km 'black hole' surrounding the injection point. Preliminary electrostatic computer simulations show a similar rayed development.

  15. Injection molded high precision freeform optics for high volume applications

    NASA Astrophysics Data System (ADS)

    Dick, Lars; Risse, Stefan; Tünnermann, Andreas

    2012-03-01

    Injection molding offers a cost-efficient method for manufacturing high precision plastic optics for high-volume applications. Optical surfaces such as flats, spheres and also aspheres are meanwhile state-of-the-art in the field of plastic optics. The demand for surfaces without symmetric properties, commonly referred to as freeform surfaces, continues to rise. Currently, new mathematical approaches are under consideration which allow for new complex optical designs. Such novel optical designs strongly encourage development of new manufacturing methods. Specifically, new surface descriptions without an axis of symmetry, new ultra precision machining methods and non-symmetrical shrinkage compensation strategies have to be developed to produce freeform optical surfaces with high precision for high-volume applications. This paper will illustrate a deterministic and efficient way for the manufacturing of ultra precision injection molding tool inserts with submicron precision and show the manufacturing of replicated freeform surfaces with micrometer range shape accuracy at diameters up to 40 mm with a surface roughness of approximately 2 nm.

  16. Characterization of a high-pressure diesel fuel injection system as a control technology option to improve engine performance and reduce exhaust emissions

    NASA Technical Reports Server (NTRS)

    Mcfadden, J. J.; Dezelick, R. A.; Barrows, R. R.

    1983-01-01

    Test results from a high pressure electronically controlled fuel injection system are compared with a commercial mechanical injection system on a single cylinder, diesel test engine using an inlet boost pressure of 2.6:1. The electronic fuel injection system achieved high pressure by means of a fluid intensifier with peak injection pressures of 47 to 69 MPa. Reduced exhaust emissions were demonstrated with an increasing rate of injection followed by a fast cutoff of injection. The reduction in emissions is more responsive to the rate of injection and injection timing than to high peak injection pressure.

  17. Multiple-injection high-throughput gas chromatography analysis.

    PubMed

    Schafer, Wes; Wang, Heather; Welch, Christopher J

    2016-08-01

    Multiple-injection techniques have been shown to be a simple way to perform high-throughput analysis where the entire experiment resides in a single chromatogram, simplifying the data analysis and interpretation. In this study, multiple-injection techniques are applied to gas chromatography with flame ionization detection and mass detection to significantly increase sample throughput. The unique issues of implementing a traditional "Fast" injection mode of multiple-injection techniques with gas chromatography and mass spectrometry are discussed. Stacked injections are also discussed as means to increase the throughput of longer methods where mass detection is unable to distinguish between analytes of the same mass and longer retentions are required to resolve components of interest. Multiple-injection techniques are shown to increase instrument throughput by up to 70% and to simplify data analysis, allowing hits in multiple parallel experiments to be identified easily. PMID:27292909

  18. Blast furnace coal injection system design for high rates

    SciTech Connect

    Snowden, B.

    1994-12-31

    Coal injection into blast furnaces is now well established as a basic technology. However, high rates of coal injection between 300 and 500 lb/thm (160 to 250 kg/thm) are a rarity. Special consideration must be given to the overall concept regarding strategic coal storage, expected equipment reliability, and back-up available to prevent furnace problems, should any of the coal feeding systems fail. British Steel and Simon Macawber now have considerable operational experience at high rates for sustained periods. The paper will discuss the points to be considered and describe the ATSI-Simon Macawber approach to providing a high level of confidence in the coal injection system.

  19. Rapid assessment and response to injecting drug use in Madras, south India.

    PubMed

    Kumar; Mudaliar; Thyagarajan; Kumar; Selvanayagam; Daniels

    2000-03-01

    HIV infection among injecting drug users (IDUs) is preventable, and in order to develop appropriate interventions, an assessment was carried out at Madras, South India using the Rapid Assessment and Response Guide on Injecting Drug Use developed by WHO. Data were collected with multiple methods from multiple sources using the principles of triangulation and induction. A total of 100 IDUs were interviewed. These interviews were complemented by focus groups and observations. A community advisory board ensured community ownership and participation. Findings showed that heroin, buprenorphine, diazepam and avil were the drugs most commonly injected. The use of pharmaceutical preparations as a 'cocktail' was also prevalent. Drug injectors interviewed were males, and most (81%) were from low-income groups living in slums. Direct (69%) as well as indirect sharing (94%) was common. Such unhygienic injecting practices, and the lack of access to sterile water, contribute to the high incidence of adverse health consequences. Compared with the buprenorphine injectors, heroin injectors were more likely to share injecting equipment (P=0.0022), inject more frequently (P=0.0013), have more drug using network members (P=0.0104), frequent 'shooting' locations (P=0.002), use the dealer's place to inject (P=0.0317), and face threats of arrest (P=0.0023). Many buprenorphine injectors managed their life without serious crises, and seemed to adopt a 'natural' harm reduction response. Sexual risk behaviour was prevalent among opioid users, and a history of commercial sex was associated with daily alcohol use (P=0.0221). The assessment led to an action plan which was presented and endorsed in an advocacy meeting by key stake-holders and decision-makers. The critical importance of implementing quality, accessible, community-oriented, and effective HIV interventions with the capacity to reach the majority of IDUs is discussed. Public health responses to injecting drug use must target changes

  20. High permeability heavy oil reservoir nitrogen injection EOR research

    NASA Astrophysics Data System (ADS)

    Wu, Xiaodong; Wang, Yining; Wang, Ruihe; Han, Guoqing; An, Yongsheng

    2014-05-01

    Nitrogen chemically very unreactive under normal showed great inertia. It is difficult to burn , dry, non-explosive , non-toxic , non-corrosive , and thus the use of safe and reliable. Coefficient of variation of nitrogen increases with increasing pressure , less affected by temperature . Under the same conditions, the ratio of the nitrogen gas formation volume factor carbon dioxide gas is high, about three times the carbon dioxide , the greater the elastic expansion of nitrogen play a beneficial role in flooding . EOR project trends increase the number of oil and gas injection gas injection from the calendar view, carbon dioxide miscible flooding gas injection EOR is the focus of the flue gas project currently has less to carry , nitrogen flooding is still subject to considerable attention. Note the nitrogen requirements of the basic conditions for enhanced oil recovery from major tectonic conditions , reservoir properties of crude nature of the gas injection timing and other aspects to consider , for different reservoir injected in different ways. Oilfield against a thick , high permeability and other characteristics, to improve oil recovery by injecting nitrogen indoor experiments conducted nitrogen injection process factors and supporting technical studies ; and introduced the field of nitrogen injection EOR field test conditions .

  1. High-pressure injection injury with river water.

    PubMed

    Greenberg, M I

    1978-06-01

    A case of high pressure injection and laceration of the calf with river water is reported, the first such case appearing in the literature. As with high pressure injection of grease, paint, paint thinner, mineral spirits, diesel oil, gasoline, and turpentine, this injury is a surgical emergency. All patients must be admitted for surgical debridement, irrigation, parenteral antibiotics, and observation. River water, contaminated by sewage and industrial wastes, has great irritative and infective potential. PMID:661048

  2. Geomechanical Reservoir Response to CO2 Injection at SNØHVIT, Norway

    NASA Astrophysics Data System (ADS)

    Chiaramonte, L.; White, J. A.

    2013-12-01

    Pressure build-up during a large-scale CO2 injection increases the potential for seal failure, fault reactivation, leakage and induced microseismicity. Careful geomechanical analysis is necessary to predict and potentially manage these effects. In the present work we investigate the geomechanical reservoir response to the CO2 injection in the Tubåen Fm at the Snøhvit site taking into account the potential compartmentalization of the storage reservoir and the in situ stress uncertainty. Compartmentalization has been suspected due to the unexpected pressure rise during operations in the storage reservoir, which led to a considerable decrease in the estimated total capacity and to the abandonment of injection operations in the Tubåen Fm. The high uncertainty in the in situ stress field makes predictions difficult, and therefore uncertainty quantification analysis is a vital component of this work. The Snøhvit gas field is located offshore in the northern Norwegian Sea (Barents Sea). CO2 is injected in the Tubåen Fm. at approximately 2600 m depth. The Tubåen Fm. corresponds to a delta plain environment dominated by fluvial distributary channels which potentially contribute to the suspected compartmentalization. Structurally the area is extensively faulted, with a dominant east-west-trending fault system, and other faults at high angles to this trend, leading to complex fault interactions. This makes fault compartmentalization a strong possibility as well. Given the injection pressure history, geometry of major faults, available estimates of the in situ stress tensor, and reservoir characteristics, we investigate the geomechanical response of the system to the CO2 injection, focusing in particular on addressing the potential reservoir compartmentalization and its impacts on injection performance, CO2 distribution and migration outside of the storage interval. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National

  3. High performance channel injection sealant invention abstract

    NASA Technical Reports Server (NTRS)

    Rosser, R. W.; Basiulis, D. I.; Salisbury, D. P. (Inventor)

    1982-01-01

    High performance channel sealant is based on NASA patented cyano and diamidoximine-terminated perfluoroalkylene ether prepolymers that are thermally condensed and cross linked. The sealant contains asbestos and, in its preferred embodiments, Lithofrax, to lower its thermal expansion coefficient and a phenolic metal deactivator. Extensive evaluation shows the sealant is extremely resistant to thermal degradation with an onset point of 280 C. The materials have a volatile content of 0.18%, excellent flexibility, and adherence properties, and fuel resistance. No corrosibility to aluminum or titanium was observed.

  4. Magnetized plasma flow injection into tokamak and high-beta compact torus plasmas

    NASA Astrophysics Data System (ADS)

    Matsunaga, Hiroyuki; Komoriya, Yuuki; Tazawa, Hiroyasu; Asai, Tomohiko; Takahashi, Tsutomu; Steinhauer, Loren; Itagaki, Hirotomo; Onchi, Takumi; Hirose, Akira

    2010-11-01

    As an application of a magnetized coaxial plasma gun (MCPG), magnetic helicity injection via injection of a highly elongated compact torus (magnetized plasma flow: MPF) has been conducted on both tokamak and field-reversed configuration (FRC) plasmas. The injected plasmoid has significant amounts of helicity and particle contents and has been proposed as a fueling and a current drive method for various torus systems. In the FRC, MPF is expected to generate partially spherical tokamak like FRC equilibrium by injecting a significant amount of magnetic helicity. As a circumstantial evidence of the modified equilibrium, suppressed rotational instability with toroidal mode number n = 2. MPF injection experiments have also been applied to the STOR-M tokamak as a start-up and current drive method. Differences in the responses of targets especially relation with beta value and the self-organization feature will be studied.

  5. Innovations in high-pressure liquid injection technique for gas chromatography: pressurized liquid injection system.

    PubMed

    Luong, Jim; Gras, Ronda; Tymko, Richard

    2003-01-01

    In gas chromatography (GC), highly volatile liquefied hydrocarbons are commonly injected using devices such as high-pressure syringes, piston valves, liquid rotary sampling valves, or vaporizing regulators. Although these techniques are adequate in some cases, there are known deficiencies. A new generation of sampling valve has been recently innovated and commercialized. Some of the highlights of the pressurized liquid injection system (PLIS) include compact size, the capability to directly couple to an injection port without the need for preinjection vaporization and transfer lines, and sample sizes ranging from 0.2 to 2.0 micro L. Although the valve has a specification of helium leak-free rating of 82.7 bar (1200 psig), the valve passes a hydrostatic pressure test of up to 414 bar (6000 psig). In the unheated version of PLIS, vaporization of solutes occur mainly because of the sheering effect of carrier gas in combination with thermal energy drawn from an injection port or a heated adaptor. This was found to be adequate for solutes with high to medium volatility of up to nC14 hydrocarbon. A higher molecular weight range of up to nC44 hydrocarbon can be achieved with the implementation of a heated version of PLIS, in which the channel of the shaft can be resistively heated at a rate of up to 400 degrees C/s. With its first introduction in May 2002, PLIS has gained acceptance amongst practitioners in GC because it addresses a key unarticulated need in sample introduction/enrichment and by specifically targeting many deficiencies encountered in contemporary high-pressure injection devices. In this paper, the design and performance of the various valve systems of PLIS, as well as industrial chromatographic applications, is presented. PMID:14629794

  6. Near-surface groundwater responses to injection of geothermal wastes

    SciTech Connect

    Arnold, S.C.

    1984-06-01

    Experiences with injecting geothermal fluids have identified technical problems associated with geothermal waste disposal. This report assesses the feasibility of injection as an alternative for geothermal wastewater disposal and analyzes hydrologic controls governing the upward migration of injected fluids. Injection experiences at several geothermal developments are presented, including: Raft River, Salton Sea, East Mesa, Otake and Hatchobaru in Japan, and Ahuachapan in El Salvador. Hydrogeologic and design/operational factors affecting the success of an injection program are identified. Hydrogeologic factors include subsidence, near-surface effects of injected fluids, and seismicity. Design/operational factors include hydrodynamic breakthrough, condition of the injection system and reservoir maintenance. Existing and potential effects of production/injection on these factors are assessed.

  7. Premixed direct injection nozzle for highly reactive fuels

    SciTech Connect

    Ziminsky, Willy Steve; Johnson, Thomas Edward; Lacy, Benjamin Paul; York, William David; Uhm, Jong Ho; Zuo, Baifang

    2013-09-24

    A fuel/air mixing tube for use in a fuel/air mixing tube bundle is provided. The fuel/air mixing tube includes an outer tube wall extending axially along a tube axis between an inlet end and an exit end, the outer tube wall having a thickness extending between an inner tube surface having a inner diameter and an outer tube surface having an outer tube diameter. The tube further includes at least one fuel injection hole having a fuel injection hole diameter extending through the outer tube wall, the fuel injection hole having an injection angle relative to the tube axis. The invention provides good fuel air mixing with low combustion generated NOx and low flow pressure loss translating to a high gas turbine efficiency, that is durable, and resistant to flame holding and flash back.

  8. Near-surface groundwater responses to injection of geothermal wastes

    SciTech Connect

    Arnold, S.C.

    1984-06-01

    This report assesses the feasibility of injection as an alternative for geothermal wastewater disposal and analyzes hydrologic controls governing the upward migration of injected fluids. Injection experiences at several geothermal developments are presented including the following: Raft River Valley, Salton Sea, East Mesa, Otake, Hatchobaru, and Ahuachapan geothermal fields.

  9. Minority carrier injection and current–voltage characteristics of Schottky diodes at high injection level

    NASA Astrophysics Data System (ADS)

    Mnatsakanov, Tigran T.; Levinshtein, Michael E.; Tandoev, Alexey G.; Yurkov, Sergey N.; Palmour, John W.

    2016-07-01

    Transport phenomena in Schottky diodes are analyzed at high injection levels of minority carriers. It is shown that the correct description of these phenomena requires that the mode of diffusion stimulated by the quasi-neutral drift (DSQD) should be considered. An analytical expression for current-voltage characteristics of a Schottky diode at high injection levels is derived. The expression predicts a seemingly paradoxical result: the higher the base doping level, the higher the voltage drop across a diode at the same current density. The analytical results are confirmed by computer simulations. The results may be important for analyses of SiC Junction Barrier Schottky (JBS) diodes at very high current densities (surge current mode).

  10. High-throughput ballistic injection nanorheology to measure cell mechanics.

    PubMed

    Wu, Pei-Hsun; Hale, Christopher M; Chen, Wei-Chiang; Lee, Jerry S H; Tseng, Yiider; Wirtz, Denis

    2012-01-01

    High-throughput ballistic injection nanorheology is a method for the quantitative study of cell mechanics. Cell mechanics are measured by ballistic injection of submicron particles into the cytoplasm of living cells and tracking the spontaneous displacement of the particles at high spatial resolution. The trajectories of the cytoplasm-embedded particles are transformed into mean-squared displacements, which are subsequently transformed into frequency-dependent viscoelastic moduli and time-dependent creep compliance of the cytoplasm. This method allows for the study of a wide range of cellular conditions, including cells inside a 3D matrix, cell subjected to shear flows and biochemical stimuli, and cells in a live animal. Ballistic injection lasts <1 min and is followed by overnight incubation. Multiple particle tracking for one cell lasts <1 min. Forty cells can be examined in <1 h. PMID:22222790

  11. Injection molding of optics for high volume consumer products

    NASA Astrophysics Data System (ADS)

    de Schipper, Rien

    2012-03-01

    For high volume consumer products using optical technology, plastics injection molding is a very suitable technology. In optical component fabrication, astonishing results are be booked. However, to achieve success, excellent performance is needed in mastering different technologies such as polymer processing, evaporated coatings, tool making, ultra-precision turning of metals and optical metrology.

  12. Injection drug users trained by overdose prevention programs: Responses to witnessed overdoses

    PubMed Central

    Lankenau, Stephen E.; Wagner, Karla D.; Silva, Karol; Kecojevic, Aleksander; Iverson, Ellen; McNeely, Miles; Kral, Alex H.

    2012-01-01

    In response to the growing public health problem of drug overdose, community-based organizations have initiated overdose prevention programs (OPP), which distribute naloxone, an opioid antagonist, and teach overdose response techniques. Injection drug users (IDUs) have been targeted for this intervention due to their high risk for drug overdose. Limited research attention has focused on factors that may inhibit or prevent IDUs who have been trained by OPPs to undertake recommended response techniques when responding to a drug overdose. IDUs (n=30) trained by two OPPs in Los Angeles were interviewed in 2010–11 about responses to their most recently witnessed drug overdose using an instrument containing both open and closed-ended questions. Among the 30 witnessed overdose events, the victim recovered in 29 cases while the outcome was unknown in one case. Participants responded to overdoses using a variety of techniques taught by OPP. Injecting the victim with naloxone was the most common recommended response while other recommended responses included stimulating the victim with knuckles, calling 911, and giving rescue breathing. Barriers preventing participants from employing recommended response techniques in certain circumstances included prior successes using folk remedies to revive a victim, concerns over attracting police to the scene, and issues surrounding access to or use of naloxone. Practical solutions, such as developing booster sessions to augment OPP, are encouraged to increase the likelihood that trained participants respond to a drug overdose with the full range of recommended techniques. PMID:22847602

  13. Effect of cavitation in high-pressure direct injection

    NASA Astrophysics Data System (ADS)

    Aboulhasanzadeh, Bahman; Johnsen, Eric

    2015-11-01

    As we move toward higher pressures for Gasoline Direct Injection and Diesel Direct Injection, cavitation has become an important issue. To better understand the effect of cavitation on the nozzle flow and primary atomization, we use a high-order accurate Discontinuous Galerkin approach using multi-GPU parallelism to simulate the compressible flow inside and outside the nozzle. Phase change is included using the six-equations model. We investigate the effect of nozzle geometry on cavitation inside the injector and on primary atomization outside the nozzle.

  14. Availability of high-pressure safety injection system in PWRs

    SciTech Connect

    Sun, Y.H.; Fresco, A.; Papazoglou, I.A.

    1983-01-01

    This paper presents an evaluation of the impact of typical variations in configuration of the design of the High Pressure Injection (HPSI) System on system unavailability. The HPSI systems in seventeen nuclear power plants were reviewed for variations in design, systems operation, testing and maintenance policies, and possible sources for common cause failures. The power plants reviewed include PWRs with two, three and four loop Reactor Coolant Systems and cover all three PWR vendors. As a result of this effort, the following five representative configurations (along with some variations) were identified and their unavailability to initiate injection was estimated.

  15. Thermo-responsive hydrogels for intravitreal injection and biomolecule release

    NASA Astrophysics Data System (ADS)

    Drapala, Pawel

    In this dissertation, we develop an injectable polymer system to enable localized and prolonged release of therapeutic biomolecules for improved treatment of Age-Related Macular Degeneration (AMD). Thermo-responsive hydrogels derived from N-isopropylacrylamide (NIPAAm) and cross-linked with poly(ethylene glycol) (PEG) poly(L-Lactic acid) (PLLA) copolymer were synthesized via free-radical polymerization. These materials were investigated for (a) phase change behavior, (b) in-vitro degradation, (c) capacity for controlled drug delivery, and (d) biocompatibility. The volume-phase transition temperature (VPTT) of the PNIPAAm- co-PEG-b-PLLA hydrogels was adjusted using hydrophilic and hydrophobic moieties so that it is ca. 33°C. These hydrogels did not initially show evidence of degradation at 37°C due to physical cross-links of collapsed PNIPAAm. Only after addition of glutathione chain transfer agents (CTA)s to the precursor did the collapsed hydrogels become fully soluble at 37°C. CTAs significantly affected the release kinetics of biomolecules; addition of 1.0 mg/mL glutathione to 3 mM cross-linker accelerated hydrogel degradation, resulting in 100% release in less than 2 days. This work also explored the effect of PEGylation in order to tether biomolecules to the polymer matrix. It was demonstrated that non-site-specific PEGylation can postpone the burst release of solutes (up to 10 days in hydrogels with 0.5 mg/mL glutathione). Cell viability assays showed that at least two 20-minute buffer extraction steps were needed to remove cytotoxic elements from the hydrogels. Clinically-used therapeutic biomolecules LucentisRTM and AvastinRTM were demonstrated to be both stable and bioactive after release form PNIPAAm-co-PEG-b-PLLA hydrogels. The thermo-responsive hydrogels presented here offer a promising platform for the localized delivery of proteins such as recombinant antibodies.

  16. Ion source and injection line for high intensity medical cyclotron

    SciTech Connect

    Jia, XianLu Guan, Fengping; Yao, Hongjuan; Zhang, TianJue; Yang, Jianjun; Song, Guofang; Ge, Tao; Qin, Jiuchang

    2014-02-15

    A 14 MeV high intensity compact cyclotron, CYCIAE-14, was built at China Institute of Atomic Energy (CIAE). An injection system based on the external H− ion source was used on CYCIAE-14 so as to provide high intensity beam, while most positron emission tomography cyclotrons adopt internal ion source. A beam intensity of 100 μA/14 MeV was extracted from the cyclotron with a small multi-cusp H− ion source (CIAE-CH-I type) and a short injection line, which the H− ion source of 3 mA/25 keV H− beam with emittance of 0.3π mm mrad and the injection line of with only 1.2 m from the extraction of ion source to the medial plane of the cyclotron. To increase the extracted beam intensity of the cyclotron, a new ion source (CIAE-CH-II type) of 9.1 mA was used, with maximum of 500 μA was achieved from the cyclotron. The design and test results of the ion source and injection line optimized for high intensity acceleration will be given in this paper.

  17. Highly Efficient Domain Walls Injection in Perpendicular Magnetic Anisotropy Nanowire

    PubMed Central

    Zhang, S. F.; Gan, W. L.; Kwon, J.; Luo, F. L.; Lim, G. J.; Wang, J. B.; Lew, W. S.

    2016-01-01

    Electrical injection of magnetic domain walls in perpendicular magnetic anisotropy nanowire is crucial for data bit writing in domain wall-based magnetic memory and logic devices. Conventionally, the current pulse required to nucleate a domain wall is approximately ~1012 A/m2. Here, we demonstrate an energy efficient structure to inject domain walls. Under an applied electric potential, our proposed Π-shaped stripline generates a highly concentrated current distribution. This creates a highly localized magnetic field that quickly initiates the nucleation of a magnetic domain. The formation and motion of the resulting domain walls can then be electrically detected by means of Ta Hall bars across the nanowire. Our measurements show that the Π-shaped stripline can deterministically write a magnetic data bit in 15 ns even with a relatively low current density of 5.34 × 1011 A/m2. Micromagnetic simulations reveal the evolution of the domain nucleation – first, by the formation of a pair of magnetic bubbles, then followed by their rapid expansion into a single domain. Finally, we also demonstrate experimentally that our injection geometry can perform bit writing using only about 30% of the electrical energy as compared to a conventional injection line. PMID:27098108

  18. Highly Efficient Domain Walls Injection in Perpendicular Magnetic Anisotropy Nanowire.

    PubMed

    Zhang, S F; Gan, W L; Kwon, J; Luo, F L; Lim, G J; Wang, J B; Lew, W S

    2016-01-01

    Electrical injection of magnetic domain walls in perpendicular magnetic anisotropy nanowire is crucial for data bit writing in domain wall-based magnetic memory and logic devices. Conventionally, the current pulse required to nucleate a domain wall is approximately ~10(12) A/m(2). Here, we demonstrate an energy efficient structure to inject domain walls. Under an applied electric potential, our proposed Π-shaped stripline generates a highly concentrated current distribution. This creates a highly localized magnetic field that quickly initiates the nucleation of a magnetic domain. The formation and motion of the resulting domain walls can then be electrically detected by means of Ta Hall bars across the nanowire. Our measurements show that the Π-shaped stripline can deterministically write a magnetic data bit in 15 ns even with a relatively low current density of 5.34 × 10(11) A/m(2). Micromagnetic simulations reveal the evolution of the domain nucleation - first, by the formation of a pair of magnetic bubbles, then followed by their rapid expansion into a single domain. Finally, we also demonstrate experimentally that our injection geometry can perform bit writing using only about 30% of the electrical energy as compared to a conventional injection line. PMID:27098108

  19. Highly Efficient Domain Walls Injection in Perpendicular Magnetic Anisotropy Nanowire

    NASA Astrophysics Data System (ADS)

    Zhang, S. F.; Gan, W. L.; Kwon, J.; Luo, F. L.; Lim, G. J.; Wang, J. B.; Lew, W. S.

    2016-04-01

    Electrical injection of magnetic domain walls in perpendicular magnetic anisotropy nanowire is crucial for data bit writing in domain wall-based magnetic memory and logic devices. Conventionally, the current pulse required to nucleate a domain wall is approximately ~1012 A/m2. Here, we demonstrate an energy efficient structure to inject domain walls. Under an applied electric potential, our proposed Π-shaped stripline generates a highly concentrated current distribution. This creates a highly localized magnetic field that quickly initiates the nucleation of a magnetic domain. The formation and motion of the resulting domain walls can then be electrically detected by means of Ta Hall bars across the nanowire. Our measurements show that the Π-shaped stripline can deterministically write a magnetic data bit in 15 ns even with a relatively low current density of 5.34 × 1011 A/m2. Micromagnetic simulations reveal the evolution of the domain nucleation – first, by the formation of a pair of magnetic bubbles, then followed by their rapid expansion into a single domain. Finally, we also demonstrate experimentally that our injection geometry can perform bit writing using only about 30% of the electrical energy as compared to a conventional injection line.

  20. DISRUPTION MITIGATION WITH HIGH-PRESSURE NOBLE GAS INJECTION

    SciTech Connect

    WHYTE, DG; JERNIGAN, TC; HUMPHREYS, DA; HYATT, AW; LASNIER, CJ; PARKS, PB; EVANS, TE; TAYLOR, PL; KELLMAN, AG; GRAY, DS; HOLLMANN, EM

    2002-10-01

    OAK A271 DISRUPTION MITIGATION WITH HIGH-PRESSURE NOBLE GAS INJECTION. High-pressure gas jets of neon and argon are used to mitigate the three principal damaging effects of tokamak disruptions: thermal loading of the divertor surfaces, vessel stress from poloidal halo currents and the buildup and loss of relativistic electrons to the wall. The gas jet penetrates as a neutral species through to the central plasma at its sonic velocity. The injected gas atoms increase up to 500 times the total electron inventory in the plasma volume, resulting in a relatively benign radiative dissipation of >95% of the plasma stored energy. The rapid cooling and the slow movement of the plasma to the wall reduce poloidal halo currents during the current decay. The thermally collapsed plasma is very cold ({approx} 1-2 eV) and the impurity charge distribution can include > 50% fraction neutral species. If a sufficient quantity of gas is injected, the neutrals inhibit runaway electrons. A physical model of radiative cooling is developed and validated against DIII-D experiments. The model shows that gas jet mitigation, including runaway suppression, extrapolates favorably to burning plasmas where disruption damage will be more severe. Initial results of real-time disruption detection triggering gas jet injection for mitigation are shown.

  1. High pressure common rail injection system modeling and control.

    PubMed

    Wang, H P; Zheng, D; Tian, Y

    2016-07-01

    In this paper modeling and common-rail pressure control of high pressure common rail injection system (HPCRIS) is presented. The proposed mathematical model of high pressure common rail injection system which contains three sub-systems: high pressure pump sub-model, common rail sub-model and injector sub-model is a relative complicated nonlinear system. The mathematical model is validated by the software Matlab and a virtual detailed simulation environment. For the considered HPCRIS, an effective model free controller which is called Extended State Observer - based intelligent Proportional Integral (ESO-based iPI) controller is designed. And this proposed method is composed mainly of the referred ESO observer, and a time delay estimation based iPI controller. Finally, to demonstrate the performances of the proposed controller, the proposed ESO-based iPI controller is compared with a conventional PID controller and ADRC. PMID:27012440

  2. Electrostatic charging of spacecraft in response to electron beam injection

    NASA Technical Reports Server (NTRS)

    Singh, Nagendra; Hwang, K. S.

    1989-01-01

    Electron beam injections from spacecraft now constitute a major activity in space research. Here, the charging level of a conducting surface when an electron beam is injected from it is investigated. Injections into both vacuum and an ambient plasma are considered. When a Maxwellian beam is injected into vacuum, the surface changes to a potential much greater than the average beam energy. The dependence of this excess is examined by considering beams with water-bag types of velocity distribution functions in which no electron has a velocity V(max) above a certain value. The electric field distribution in the electron sheath near the surface is determined by the pressure distribution. Thus, the surface potential is determined not only by V(max) but by all the beam parameters. The ambient plasma reduces the charging level and causes an oscillation in the surface potential. The oscillation frequency is the electron-plasma frequency associated with the ambient plasma.

  3. 'It's your life!': injecting drug users, individual responsibility and hepatitis C prevention.

    PubMed

    Fraser, Suzanne

    2004-04-01

    Health promotion materials on hepatitis C prevention and safe injecting enjoin injecting drug users to produce ethical selves through relatively rigid social and hygiene-related conduct. This article examines a sample of safe injecting and hepatitis C prevention health promotion materials, and interview data gathered from injecting drug users, to consider the ways in which the notion of individual responsibility functions within them. I argue that the primacy of the individual in western culture is indeed reflected in hepatitis C and safe injecting materials and, that for a range of reasons, injecting drug users also make use of notions of individual responsibility. The article concludes by considering the social and health implications of this individualist approach to injecting drug use and health promotion, and by suggesting ways in which effective materials which do not focus solely on the individual can be created. PMID:15068637

  4. Injectable polyHIPEs as high-porosity bone grafts.

    PubMed

    Moglia, Robert S; Holm, Jennifer L; Sears, Nicholas A; Wilson, Caitlin J; Harrison, Dawn M; Cosgriff-Hernandez, Elizabeth

    2011-10-10

    Polymerization of high internal phase emulsions (polyHIPEs) is a relatively new method for the production of high-porosity scaffolds. The tunable architecture of these polyHIPE foams makes them attractive candidates for tissue engineered bone grafts. Previously studied polyHIPE systems require either toxic diluents or high cure temperatures which prohibit their use as an injectable bone graft. In contrast, we have developed an injectable polyHIPE that cures at physiological temperatures to a rigid, high-porosity foam. First, a biodegradable macromer, propylene fumarate dimethacrylate (PFDMA), was synthesized that has appropriate viscosity and hydrophobicity for emulsification. The process of surfactant selection is detailed with particular focus on the key structural features of both polymer (logP values, hydrogen bond acceptor sites) and surfactant (HLB values, hydrogen bond donor sites) that enable stable HIPE formation. Incubation of HIPEs at 37 °C was used to initiate radical cross-linking of the unsaturated double bond of the methacrylate groups to polymerize the continuous phase and lock in the emulsion geometry. The resulting polyHIPEs exhibited ~75% porosity, pore sizes ranging from 4 to 29 μm, and an average compressive modulus and strength of 33 and 5 MPa, respectively. These findings highlight the great potential of these scaffolds as injectable, tissue engineered bone grafts. PMID:21861465

  5. Injectable PolyHIPEs as High Porosity Bone Grafts

    PubMed Central

    Moglia, Robert S.; Holm, Jennifer L.; Sears, Nicholas A.; Wilson, Caitlin J.; Harrison, Dawn M.; Cosgriff-Hernandez, Elizabeth

    2011-01-01

    Polymerization of high internal phase emulsions (polyHIPEs) is a relatively new method for the production of high porosity scaffolds. The tunable architecture of these polyHIPE foams make them attractive candidates for tissue engineered bone grafts. Previously studied polyHIPE systems require either toxic diluents or high cure temperatures which prohibit their use as an injectable bone graft. In contrast, we have developed an injectable polyHIPE that cures at physiological temperatures to a rigid, high-porosity foam. First, a biodegradable macromer, propylene fumarate dimethacrylate (PFDMA), was synthesized that has appropriate viscosity and hydrophobicity for emulsification. The process of surfactant selection is detailed with particular focus on the key structural features of both polymer (log P values, hydrogen bond acceptor sites) and surfactant (HLB values, hydrogen bond donor sites) that enable stable HIPE formation. Incubation of HIPEs at 37°C was used to initiate radical crosslinking of the unsaturated double bond of the methacrylate groups to polymerize the continuous phase and lock in the emulsion geometry. The resulting polyHIPEs exhibited ~75% porosity, pore sizes ranging from 4 to 29 μm, and an average compressive modulus and strength of 33 and 5 MPa, respectively. These findings highlight the great potential of these scaffolds as injectable, tissue engineered bone grafts. PMID:21861465

  6. High-Resolution Simulations of Coal Injection in A Gasifier

    SciTech Connect

    Li, Tingwen; Gel, Aytekin; Syamlal, M; Guenther, Chris; Pannala, Sreekanth

    2010-01-01

    This study demonstrates an approach to effectively combine high- and low-resolution simulations for design studies of industrial coal gasifier. The flow-field data from a 10 million cell full-scale simulation of a commercial-scale gasifier were used to construct a reduced configuration to economically study the coal injection in detail. High-resolution numerical simulations of the coal injection were performed using the open-source code MFIX running on a high performance computing system. Effects of grid resolution and numerical discretization scheme on the predicted behavior of coal injection and gasification kinetics were analyzed. Pronounced differences were predicted in the devolatilization and steam gasification rates because of different discretization schemes, implying that a high-order numerical scheme is required to predict well the unsteady gasification process on an adequately resolved grid. Computational costs for simulations of varying resolutions are presented to illustrate the trade-off between the accuracy of solution and the time-to-solution, an important consideration when engineering simulations are used for the design of commercial-scale units.

  7. Electron injection dynamics in high-potential porphyrin photoanodes.

    PubMed

    Milot, Rebecca L; Schmuttenmaer, Charles A

    2015-05-19

    promising sensitizers because their high reduction potentials are compatible with the energy requirements of water oxidation. TRTS of free-base and metalated pentafluorophenyl porphyrins reveal inefficient electron injection into TiO2 nanoparticles but more efficient electron injection into SnO2 nanoparticles. With SnO2, injection time scales depend strongly on the identity of the central substituent and are affected by competition with excited-state deactivation processes. Heavy or paramagnetic metal ions increase the electron injection time scale by roughly one order of magnitude relative to free-base or Zn(2+) porphyrins due to the possibility of electron injection from longer-lived, lower-lying triplet states. Furthermore, electron injection efficiency loosely correlates with DSSC performance. The carboxylate anchoring group is commonly used to bind DSSC sensitizers to metal oxide surfaces but typically is not stable under the aqueous and oxidative conditions required for water oxidation. Electron injection efficiency of several water-stable alternatives, including phosphonic acid, hydroxamic acid, acetylacetone, and boronic acid, were evaluated using TRTS, and hydroxamate was found to perform as well as the carboxylate. The next challenge is incorporating a water oxidation catalyst into the design. An early example, in which an Ir-based precatalyst is cosensitized with a fluorinated porphyrin, reveals decreased electron injection efficiency despite an increase in photocurrent. Future research will seek to better understand and address these difficulties. PMID:25938858

  8. Cardiovascular responses produced by central injection of hydrogen peroxide in conscious rats.

    PubMed

    Máximo Cardoso, Leonardo; de Almeida Colombari, Débora Simões; Vanderlei Menani, José; Alves Chianca, Deoclécio; Colombari, Eduardo

    2006-12-11

    Reactive oxygen species (ROS) have been shown to modulate neuronal synaptic transmission and may play a role on the autonomic control of the cardiovascular system. In this study we investigated the effects produced by hydrogen peroxide (H(2)O(2)) injected alone or combined with the anti-oxidant agent N-acetil-l-cysteine (NAC) or catalase into the fourth brain ventricle (4th V) on mean arterial pressure and heart rate of conscious rats. Moreover the involvement of the autonomic nervous system on the cardiovascular responses to H(2)O(2) into the 4th V was also investigated. Male Holtzman rats (280-320 g) with a stainless steel cannula implanted into the 4th V and polyethylene cannulas inserted into the femoral artery and vein were used. Injections of H(2)O(2) (0.5, 1.0 and 1.5 micromol/0.2 microL, n=6) into the 4th V produced transient (for 10 min) dose-dependent pressor responses. The 1.0 and 1.5 micromol doses of H(2)O(2) also produced a long lasting bradycardia (at least 24 h with the high dose of H(2)O(2)). Prior injection of N-acetyl-l-cysteine (250 nmol/1 microL/rat) into the 4th V blockade the pressor response and attenuated the bradycardic response to H(2)O(2) (1 micromol/0.5 microL/rat, n=7) into the 4th V. Intravenous (i.v.) atropine methyl bromide (1.0 mg/kg, n=11) abolished the bradycardia but did not affect the pressor response to H(2)O(2). Prazosin hydrochloride (1.0 mg/kg, n=6) i.v. abolished the pressor response but did not affect the bradycardia. The increase in the catalase activity (500 UEA/1 microL/rat injected into the 4th V) also abolished both, pressor and bradycardic responses to H(2)O(2). The results suggest that increased ROS availability into 4th V simultaneously activate sympathetic and parasympathetic outflow inducing pressor and bradycardic responses. PMID:17113926

  9. Aging study of boiling water reactor high pressure injection systems

    SciTech Connect

    Conley, D.A.; Edson, J.L.; Fineman, C.F.

    1995-03-01

    The purpose of high pressure injection systems is to maintain an adequate coolant level in reactor pressure vessels, so that the fuel cladding temperature does not exceed 1,200{degrees}C (2,200{degrees}F), and to permit plant shutdown during a variety of design basis loss-of-coolant accidents. This report presents the results of a study on aging performed for high pressure injection systems of boiling water reactor plants in the United States. The purpose of the study was to identify and evaluate the effects of aging and the effectiveness of testing and maintenance in detecting and mitigating aging degradation. Guidelines from the United States Nuclear Regulatory Commission`s Nuclear Plant Aging Research Program were used in performing the aging study. Review and analysis of the failures reported in databases such as Nuclear Power Experience, Licensee Event Reports, and the Nuclear Plant Reliability Data System, along with plant-specific maintenance records databases, are included in this report to provide the information required to identify aging stressors, failure modes, and failure causes. Several probabilistic risk assessments were reviewed to identify risk-significant components in high pressure injection systems. Testing, maintenance, specific safety issues, and codes and standards are also discussed.

  10. Injectable and responsively degradable hydrogel for personalized photothermal therapy.

    PubMed

    Wang, Changping; Wang, Xinyu; Dong, Kunyu; Luo, Jian; Zhang, Qiang; Cheng, Yiyun

    2016-10-01

    Near infrared-absorbing hydrogels are used for the repeated photothermal treatments of cancer. However, a long-term retention of hydrogel in the body leads to increased risk of toxicity. Here we developed an injectable and on-demand degradable hydrogel to conduct the repeated photothermal therapies (PTTs). Alginate-calcium hydrogel immobilized dendrimer-encapsulated platinum nanoparticles (DEPts) in its matrix represented excellent biocompatibility, and was degraded upon injecting chelates. Results from the in vivo studies reveal that the hydrogel/DEPts-mediated repeated PTTs suppressed tumor growth efficiently, and the hydrogel was degraded on-demand to allow renal secretion of DEPts out of the body. Furthermore, coating hydrogel/DEPts on the tumor instead of intratumoral injection could still ablate tumor efficiently. Our investigation provides a smart and safe hydrogel for photothermal cancer therapy. PMID:27449949

  11. High intensity ion beam injection into the 88-inch cyclotron

    SciTech Connect

    Wutte, Daniela; Clark, Dave J.; Laune, Bernard; Leitner,Matthaeus A.; Lyneis, Claude M.

    2000-05-31

    Low cross section experiments to produce super-heavyelements have increased the demand for high intensity heavy ion beams atenergies of about 5 MeV/nucleon at the 88-Inch Cyclotron at the LawrenceBerkeley National Laboratory. Therefore, efforts are underway to increasethe overall ion beam transmission through the axial injection line andthe cyclotron. The ion beam emittance has been measured for various ionmasses and charge states. Beam transport simulations including spacecharge effects were performed for both of the injection line and the ionsource extraction. The relatively low nominal injection voltage of 10 kVwas found to be the main factor for ion beam losses, because of beam blowup due to space charge forces at higher intensities. Consequently,experiments and simulations have been performed at higherinjectionenergies, and it was demonstrated that the ion beams could still becentered in the cyclotron at these energies. Therefore, the new injectorion source VENUS and its ion beam transport system (currently underconstruction at the 88-Inch Cyclotron) are designed for extractionvoltages up to 30 kV.

  12. High rates of sustained virological response in hepatitis C virus-infected injection drug users receiving directly observed therapy with peginterferon alpha-2a (40KD) (PEGASYS) and once-daily ribavirin.

    PubMed

    Waizmann, Michael; Ackermann, Grit

    2010-06-01

    This retrospective study evaluated the efficacy and tolerability of directly observed therapy with peginterferon alfa-2a and once-daily ribavirin (RBV) for chronic hepatitis C in 49 opioid-addicted injection drug users (IDUs) participating in a drug treatment program at a specialized outpatient center. Patients also received prophylactic citalopram to minimize the risk of interferon-induced depression. Patients had daily access to and support from specialist physicians, nurses and counseling services at the center, and a 24-hour helpline. Sustained virological response was achieved by 48 of 49 patients (98%) overall, including 20 of 21 (95%) hepatitis C virus (HCV) Genotype 1/4-infected patients and 28 of 28 (100%) Genotype 2/3-infected patients. Treatment was well tolerated, and no unexpected side effects of peginterferon treatment were seen. The safety profile of once-daily RBV was not different from twice-daily dosing. Decline in hemoglobin levels was similar to those reported in clinical trials including once-daily RBV and did not lead to dose reduction or treatment withdrawal. Our data demonstrate that HCV-infected IDUs on stable L-polamidone (methadone) or buprenorphine maintenance can be successfully and safely treated with peginterferon alfa-2a and RBV in an optimal substitution setting. PMID:20362408

  13. System Study: High-Pressure Coolant Injection 1998–2013

    SciTech Connect

    Schroeder, John Alton

    2015-01-31

    This report presents an unreliability evaluation of the high-pressure coolant injection system (HPCI) at 25 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCI results.

  14. System Study: High-Pressure Coolant Injection 1998-2014

    SciTech Connect

    Schroeder, John Alton

    2015-12-01

    This report presents an unreliability evaluation of the high-pressure coolant injection system (HPCI) at 25 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCI results.

  15. System Study: High-Pressure Safety Injection 1998-2014

    SciTech Connect

    Schroeder, John Alton

    2015-12-01

    This report presents an unreliability evaluation of the high-pressure safety injection system (HPSI) at 69 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPSI results.

  16. System Study: High-Pressure Safety Injection 1998–2013

    SciTech Connect

    Schroeder, John Alton

    2015-02-01

    This report presents an unreliability evaluation of the high-pressure safety injection system (HPSI) at 69 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPSI results.

  17. System Study: High-Pressure Safety Injection 1998–2012

    SciTech Connect

    T. E. Wierman

    2013-10-01

    This report presents an unreliability evaluation of the high-pressure safety injection system (HPSI) at 69 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2012 for selected components were obtained from the Equipment Performance and Information Exchange (EPIX). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPSI results.

  18. System Study: High-Pressure Coolant Injection 1998-2012

    SciTech Connect

    T. E. Wierman

    2013-10-01

    This report presents an unreliability evaluation of the high-pressure coolant injection system (HPCI) at 69 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2012 for selected components were obtained from the Equipment Performance and Information Exchange (EPIX). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCI results.

  19. Experiment on fuel injection in high-enthalpy flow

    NASA Astrophysics Data System (ADS)

    Tanno, Hideyuki; Komuro, Tomoyuki; Sato, Kazuo; Itoh, Katsuhiro; Ueda, Shuichi

    2001-04-01

    An experiment of inert gas injection into a high enthalpy hypersonic air flow is described. Gaseous helium at room temperature was injected transversely through four (phi) 1.5 mm circular sonic injectors at a spacing of 20 mm, which was located 28 mm downstream from a backward-facing step of 4 mm height. The experiment was carried out in the high enthalpy shock tunnel HIEST under the free stream test condition at Mach number of 6.5 and at the velocity of 4 km/s. The purpose of the experiment was to examine transient behavior of the helium jet mixing with the test air flow. Sequential Schlieren flow visualization with high-speed CCD camera of 1 (mu) sec exposure time have been used. Pitot pressure profile in the helium jet was measured at three stream-wise location. The measurements showed that the helium jet reached to the steady state in less than 2 msec, which was within HIEST test duration.

  20. Applications of high-speed dust injection to magnetic fusion

    SciTech Connect

    Wang, Zhehui; Li, Yangfang

    2012-08-08

    It is now an established fact that a significant amount of dust is produced in magnetic fusion devices due to plasma-wall interactions. Dust inventory must be controlled, in particular for the next-generation steady-state fusion machines like ITER, as it can pose significant safety hazards and degrade performance. Safety concerns are due to tritium retention, dust radioactivity, toxicity, and flammability. Performance concerns include high-Z impurities carried by dust to the fusion core that can reduce plasma temperature and may even induce sudden termination of the plasma. We have recognized that dust transport, dust-plasma interactions in magnetic fusion devices can be effectively studied experimentally by injection of dust with known properties into fusion plasmas. Other applications of injected dust include diagnosis of fusion plasmas and edge localized mode (ELM)'s pacing. In diagnostic applications, dust can be regarded as a source of transient neutrals before complete ionization. ELM's pacing is a promising scheme to prevent disruptions and type I ELM's that can cause catastrophic damage to fusion machines. Different implementation schemes are available depending on applications of dust injection. One of the simplest dust injection schemes is through gravitational acceleration of dust in vacuum. Experiments at Los Alamos and Princeton will be described, both of which use piezoelectric shakers to deliver dust to plasma. In Princeton experiments, spherical particles (40 micron) have been dropped in a systematic and reproducible manner using a computer-controlled piezoelectric bending actuator operating at an acoustic (0,2) resonance. The circular actuator was constructed with a 2.5 mm diameter central hole. At resonance ({approx} 2 kHz) an applied sinusoidal voltage has been used to control the flux of particles exiting the hole. A simple screw throttle located {approx}1mm above the hole has been used to set the magnitude of the flux achieved for a given

  1. Determination of injection molding process windows for optical lenses using response surface methodology.

    PubMed

    Tsai, Kuo-Ming; Wang, He-Yi

    2014-08-20

    This study focuses on injection molding process window determination for obtaining optimal imaging optical properties, astigmatism, coma, and spherical aberration using plastic lenses. The Taguchi experimental method was first used to identify the optimized combination of parameters and significant factors affecting the imaging optical properties of the lens. Full factorial experiments were then implemented based on the significant factors to build the response surface models. The injection molding process windows for lenses with optimized optical properties were determined based on the surface models, and confirmation experiments were performed to verify their validity. The results indicated that the significant factors affecting the optical properties of lenses are mold temperature, melt temperature, and cooling time. According to experimental data for the significant factors, the oblique ovals for different optical properties on the injection molding process windows based on melt temperature and cooling time can be obtained using the curve fitting approach. The confirmation experiments revealed that the average errors for astigmatism, coma, and spherical aberration are 3.44%, 5.62%, and 5.69%, respectively. The results indicated that the process windows proposed are highly reliable. PMID:25321095

  2. Modulation response characteristics of optical injection-locked cascaded microring laser

    NASA Astrophysics Data System (ADS)

    Yu, Shaowei; Pei, Li; Liu, Chao; Wang, Yiqun; Weng, Sijun

    2014-09-01

    Modulation bandwidth and frequency chirping of the optical injection-locked (OIL) microring laser (MRL) in the cascaded configuration are investigated. The unidirectional operation of the MRL under strong injection allows simple and cost-saving monolithic integration of the OIL system on one chip as it does not need the use of isolators between the master and slave lasers. Two cascading schemes are discussed in detail by focusing on the tailorable modulation response. The chip-to-power ratio of the cascaded optical injection-locked configuration has decreased by up to two orders of magnitude, compared with the single optical injection-locked configuration.

  3. Intimate Injection Partnerships Are at Elevated Risk of High-Risk Injecting: A Multi-Level Longitudinal Study of HCV-Serodiscordant Injection Partnerships in San Francisco, CA

    PubMed Central

    Morris, Meghan D.; Evans, Jennifer; Montgomery, Martha; Yu, Michelle; Briceno, Alya; Page, Kimberly; Hahn, Judith A.

    2014-01-01

    Background It is increasingly recognized that the risk for HIV and hepatitis C (HCV) transmission among people who inject drugs (PWID), such as syringe sharing, occurs in the context of relationships between (at least) two people. Evidence suggests that the risk associated with injection behavior varies with injection partner types. Methods We utilized longitudinal dyad-level data from a study of young PWID from San Francisco (2006 to 2013) to investigate the relationship-level factors influencing high-risk injecting within HCV-serodiscordant injection partners (i.e., individuals who injected together ≥5 times in the prior month). Utilizing data from 70 HCV-serodiscordant injection partnerships, we used generalized linear models to examine relationship-level predictors (i.e., partnership composition, partnership closeness, and partnership dynamics) of: (1) receptive syringe sharing (RSS); and (2) receptive cooker use (RCU), as reported by the HCV-negative injection partner. Results As reported by the “at-risk” HCV-negative injection partner, receptive syringe sharing (RSS) and receptive cooker use (RCU) were 19% and 33% at enrollment, and 11% and 12% over all visits (total follow-up time 55 person-years) resulting in 13 new HCV-infections (incidence rate: 23.8/100 person-years). Person-level factors, injection partnership composition, and partnership dynamics were not significantly associated with either RSS or RCU. Instead, intimate injection partnerships (those who lived together and were also in a sexual relationship) were independently associated with a 5-times greater risk of both RSS and a 7-times greater risk of RCU when compared to injecting only partnerships. Conclusion Our findings suggest a positive, and amplified effect of relationship factors on injecting drug risk behaviors among young PWID injection partnerships. The majority of interventions to reduce injection drug use related harms focus on individual-based education to increase drug use

  4. Seismogenic response to fluid injection operations in Oklahoma and California: Implications for crustal stresses

    NASA Astrophysics Data System (ADS)

    Goebel, T.; Aminzadeh, F.

    2015-12-01

    The seismogenic response to induced pressure changes provides insight into the proximity to failure of faults close to injection sites. Here, we examine possible seismicity rate changes in response to wastewater disposal and enhanced oil recovery operations in hydrocarbon basins in California and Oklahoma. We test whether a statistically significant rate increase exists within these areas and determine the corresponding timing and location based on nonparametric modeling of background seismicity rates. Annual injection volumes increased monotonically since ~2001 in California and ~1998 in Oklahoma. While OK experienced a recent surge in seismic activity which exceeded the 95% confidence limit of a stationary Poisson process in ~2010, seismicity in CA showed no increase in background rates between 1980 and 2014. A systematic analysis of frequency-magnitude-distributions (FMDs) of likely induced earthquakes in OK indicates that FMDs are depleted in large-magnitude events. Seismicity in CA hydrocarbon basins, on the other hand, shows Gutenberg-Richter type FMDs and b~1. Moreover, the earthquakes and injection operations occur preferably in distinct areas in CA whereas in OK earthquakes occur closer to injection wells than expected from a random uniform process. To test whether injection operations may be responsible for the strongly different seismicity characteristics in CA and OK, we compare overall well density, wellhead pressures, peak and cumulative rates as well as injection depths. We find that average injection rates, pressures and volumes are comparable between CA and OK and that injection occurs on average 0.5 km deeper in CA than in OK. Thus, the here tested operational parameters can not easily explain the vastly different seismogenic response to injection operations in CA and OK, and may only be of secondary importance for the resulting earthquake activity. The potential to induce earthquakes by fluid injection operations is likely controlled by the

  5. Ketamine Injection among High Risk Youth: Preliminary Findings from New York City

    PubMed Central

    Lankenau, Stephen E.; Clatts, Michael C.

    2007-01-01

    Ketamine, a synthetic drug commonly consumed by high risk youth, produces a range of experiences, including sedation, dissociation, and hallucinations. While ketamine is more typically sniffed, we describe a small sample of young ketamine injectors (n=25) in New York City and highlight risks associated with this emerging type of injection drug use. Our findings indicate that the injection practices, injection groups, and use norms surrounding ketamine often differ from other injection drug use: intramuscular injections were more common than intravenous injections; injection groups were often large; multiple injections within a single episode were common; bottles rather than cookers were shared; and the drug was often obtained for free. Our findings suggest that the drug injection practices exercised by ketamine injectors place them at risk for bloodborne pathogens, such as HIV, HBV, and HCV. We conclude that ketamine injectors represent an emerging, though often hidden, population of injection drug users, particularly among high risk, street-involved youth. PMID:17440604

  6. Approaching high temperature photon counting with electron-injection detectors

    NASA Astrophysics Data System (ADS)

    Fathipour, V.; Jang, S. J.; Hassaninia, I.; Mohseni, H.

    2014-10-01

    Our group has designed and developed a novel telecom band photon detector called the electron-injection detector. The detector provides a high avalanche-free internal-amplification and a stable excess noise factor of near unity while operating at linear-mode with low bias voltages. In our previous reports on un-isolated detectors, the large dark current of the detectors prevented long integration times in the camera. Furthermore, the bandwidth of the un-isolated detectors was in the KHz range. Recently, by changing the 3D geometry and isolating the detectors from each other, we have achieved 3 orders of magnitude reduction in dark current at same bias voltage and temperature compared to our previous results. Isolated detectors have internal dark current densities of 0.1nA/cm2 at 160 K. Furthermore, they have a bandwidth that is 4 orders of magnitude higher than the un-isolated devices. In this paper we report room temperature and low temperature characteristics of the isolated electron-injection detectors. We show that the measured optical gain displays a small dependence on temperature over our measured range down to 220 K.

  7. Low viscosity highly concentrated injectable nonaqueous suspensions of lysozyme microparticles.

    PubMed

    Miller, Maria A; Engstrom, Joshua D; Ludher, Baltej S; Johnston, Keith P

    2010-01-19

    Subcutaneous injection of concentrated protein and peptide solutions, in the range of 100-400 mg/mL, is often not possible with a 25- to 27-gauge needle, as the viscosity can be well above 50 cP. Apparent viscosities below this limit are reported for suspensions of milled lysozyme microparticles up to nearly 400 mg/mL in benzyl benzoate or benzyl benzoate mixtures with safflower oils through a syringe with a 25- to 27-gauge needle at room temperature. These apparent viscosities were confirmed using a cone-and-plate rheometer. The intrinsic viscosity regressed from the Kreiger-Dougherty model was only slightly above the Einstein value of 2.5, indicating the increase in viscosity relative to that of the solvent was caused primarily by the excluded volume. Thus, the increases in viscosity from electrical double layer interactions (electroviscous effects), solvation of the particles, or deviations of the particle shape from a spherical geometry were minimal, and much smaller than typically observed for proteins dissolved in aqueous solutions. The small electroviscous effects are expected given the negligible zeta potential and thin double layers in the low dielectric constant organic solvent. The suspensions were resuspendable after a year, with essentially constant particle size after two months as measured by static light scattering. The lower apparent viscosities for highly concentrated protein suspensions relative to protein solutions, coupled with these favorable characteristics upon resuspension, may offer novel opportunities for subcutaneous injection of therapeutic proteins. PMID:19803503

  8. Using brine extraction to isolate the pressure responses from CO2 injection operations

    NASA Astrophysics Data System (ADS)

    Bandilla, K.; Court, B.; Celia, M. A.

    2011-12-01

    Many potential carbon dioxide (CO2) injection sites are in large sedimentary basins, and it seems reasonable to expect that multiple operators will be injecting into the same formation. While the supercritical CO2 plumes are not expected to intersect, the pressure responses will most likely overlap. This will lead to overlapping Areas-of-Review (AoR), leading to complications for both the operators and the regulators. Also, existing injection operations will be impacted by new operations that come online at a later time, and as such existing AoRs will need to be updated to account for the pressure interference. One option to avoid pressure interference is to locate injection operations far from one other. However, this would greatly reduce the overall storage efficiency of the injection formation and increase the regulatory burden by requiring a basin-wide planning process. Active pressure management through brine production is one option to limit the spatial extent of the pressure responses, thereby avoiding pressure interference while also allowing for a greater spatial density of injection operations. For example, each injection operation could be surrounded by a ring of brine production wells, not dissimilar to an enhanced oil recovery operation, thereby limiting the far field impact of the CO2 injection. In this presentation we use a hypothetical model based on a section of the Illinois Basin to show the effectiveness of brine extraction in isolating the pressure responses of multiple injection operations. The model domain contains several injection wells, with the different injection operations brought on-line in a time-staggered fashion. The impact of factors such as brine extraction rates and extraction well spacing on the AoRs is investigated. A vertically integrated approach is used to numerically solve the two-phase flow problem, which greatly reduces the computational cost of the simulations. The results of this study show that brine extraction can be

  9. Unexpectedly high injection drug use, HIV and hepatitis C prevalence among female sex workers in the Republic of Mauritius.

    PubMed

    Johnston, Lisa Grazina; Corceal, Sewraz

    2013-02-01

    Female sex workers (FSW) often have a disproportionately high prevalence of HIV infection and they, along with their clients, are considered a core group contributing to the transmission of HIV in many countries. In 2010, females who reported having vaginal/anal/oral sex in the last 6 months with a male in exchange for money or gifts, aged ≥15 years, and living in Mauritius were recruited into a survey using respondent driven sampling. Consenting females (n = 299) completed a behavioral questionnaire and provided venous blood for HIV, HCV and HBV testing. HIV seroprevalence among FSW was 28.9 % and 43.8 % were infected with HCV; among HIV seropositive FSW, 88.2 % were also infected with HCV. Almost 40 % of FSW reported injecting drugs sometime in their lives and 30.5 % of all FSW reported doing so in the previous 3 months. Among those who ever injected drugs, 82.5 % did so in the past 3 months and among those 60 % reported injecting drugs at least once a day. Among FSW who ever injected drugs, 17.5 % reported sharing a needle at last injection. Regression analyses found injection drug use behaviors to be positively associated with HIV seroprevalence. These findings indicate that FSW, especially those who inject drugs, are at high risk for HIV and HCV infection and transmission and illustrates the need for gender responsive HIV and injection drug use prevention and treatment models that respond to the unique situations that affect this population. PMID:22851154

  10. An injectable, low-toxicity phospholipid-based phase separation gel that induces strong and persistent immune responses in mice.

    PubMed

    Han, Lu; Xue, Jiao; Wang, Luyao; Peng, Ke; Zhang, Zhirong; Gong, Tao; Sun, Xun

    2016-10-01

    Sustained antigen delivery using incomplete Freund's adjuvant (IFA) can induce strong, long-term immune response, but it can also cause severe side effects. Here we describe an injectable, phospholipid-based phase separation gel (PPSG) that readily transforms in situ into a drug depot. PPSG loaded with the model antigen ovalbumin (OVA) supported sustained OVA release in mice that lasted nearly one month. Immunizing mice with a single injection of PPSG/OVA elicited a strong and persistent increase in titers of OVA-specific IgG, IgG1 and IgG2a. Co-administering CpG-ODN further increased antibody titers. Such co-administration recruited dendritic cells to injection sites and activated dendritic cells in the draining lymph nodes. Moreover, immunization with PPSG/OVA/CpG resulted in potent memory antibody responses and high frequency of memory T cells. Remarkably, PPSG/OVA/CpG was associated with much lower toxicity at injection sites than IFA/OVA/CpG, and it showed no systemic toxicity such as to lymph nodes or spleen. These findings illustrate the potential of injectable PPSG for sustained, minimally toxic delivery of antigens and adjuvants. PMID:27522253

  11. The Social Buffering Effect of Playful Handling on Responses to Repeated Intraperitoneal Injections in Laboratory Rats

    PubMed Central

    Cloutier, Sylvie; Wahl, Kim; Baker, Chelsea; Newberry, Ruth C

    2014-01-01

    Handling small animals for veterinary and experimental procedures can negatively affect animal wellbeing. We hypothesized that playful handling (tickling) would decrease stress associated with repeated injections in adult laboratory rats, especially those with prior tickling experience. We compared responses of 4 groups of male Sprague–Dawley rats to intraperitoneal injection of saline daily for 10 d. Rats either tickled or not tickled as juveniles (2 min/d for 21 d) were exposed as adults to either a passive hand or tickling for 2 min immediately before and after injections. Rates of vocalization (22- and 50-kHz ultrasonic vocalizations (USV), indicative of negative and positive affective states, respectively, and audible calls indicative of pain and discomfort) were quantified before, during, and after injection. Tickling before and after injection, especially when combined with juvenile tickling experience (ending 40 to 50 d earlier), increased 50-kHz USV rates before and after injection, reduced audible call rate during injection, and decreased the duration of the injection procedure. The treatments did not affect indicators of physiologic stress (body weight change; fecal corticosteroid levels). We conclude that playful handling performed in association with a mildly aversive procedure serves as a useful refinement by inducing a positive affective state that mitigates the aversiveness of the procedure and makes rats easier to handle, especially when they have been accustomed to tickling as juveniles. PMID:24602543

  12. The Effects of Intracellular Iontophoretic Injection of Calcium and Sodium Ions on the Light Response of Limulus Ventral Photoreceptors

    PubMed Central

    Lisman, J. E.; Brown, J. E.

    1972-01-01

    During intracellular iontophoretic injection of Ca++ into Limulus ventral photoreceptor cells, there is a progressive diminution of the light response. Following Ca++ injection, the size of the light response slowly recovers. Similarly, there is a progressive diminution of the light response during intracellular injection of Na+ and recovery after the injection is stopped. The rate of diminution during Na+ injection is greater for higher [Ca++]out. In solutions which contain 0.1 mM Ca++, there is nearly no progressive decrease in the size of the light response during Na+ injection. Intracellular injections of Li+ or K+ do not progressively decrease the size of the light response. We propose that an increase in [Na+]in leads to an increase in [Ca++]in and that an increase in [Ca++]in by any means leads to a reduction in responsiveness to light. PMID:5025746

  13. Humoral immune response of mice injected with tocopherol after exposure to X-radiation

    SciTech Connect

    Roy, R.M.; Petrella, M.

    1987-01-01

    Serum haemagglutination (HA) titers have been determined for irradiated and non-irradiated mice responding to injection of two different concentrations of sheep red blood cells (SRBC) 24 to 48 hours after irradiation and immediate intraperitoneal injection of 2.5 mg DL alpha-tocopherol, the emulsifying vehicle, or saline. Mice maintained on tocopherol-deficient diets for 8 weeks post-weaning and those on regular diets exhibited increased IgG titers during peak response when injected with vitamin E. This partially alleviated the radiation-depression of the primary immune response induced by the smaller SRBC injection. This stimulatory effect was most significant in mice maintained on vitamin E-deficient diets. The HA titers of irradiated and non-irradiated mice maintained on normal rations were determined following a 10-fold increase in the SRBC inoculation. Antibody titer was greater following injection of the higher concentration of SRBC but post-irradiation injection of tocopherol immediately or 24 hours after irradiation did not enhance immune response. At the higher SRBC concentration maximum observed HA titers decreased with increasing dose of radiation; however, tocopherol had no significant dose-reducing effect. Tocopherol toxicity as manifested by depressed HA titers was observed occasionally in non-irradiated mice challenged with the higher concentration of SRBC.

  14. Microbial community response to the CO2 injection and storage in the saline aquifer, Ketzin, Germany

    NASA Astrophysics Data System (ADS)

    Morozova, Daria; Zettlitzer, Michael; Vieth, Andrea; Würdemann, Hilke

    2010-05-01

    The concept of CO2 capture and storage in the deep underground is currently receiving great attention as a consequence of the effects of global warming due to the accumulation of carbon dioxide gas in the atmosphere. The EU funded CO2SINK project is aimed as a pilot storage of CO2 in a saline aquifer located near Ketzin, Germany. One of the main aims of the project is to develop efficient monitoring procedures for assessing the processes that are triggered in the reservoir by CO2 injection. This study reveals analyses of the composition and activity of the microbial community of a saline CO2 storage aquifer and its response to CO2 injection. The availability of CO2 has an influence on the metabolism of both heterotrophic microorganisms, which are involved in carbon cycle, and lithoautotrophic microorganisms, which are able to use CO2 as the sole carbon source and electron acceptor. Injection of CO2 in the supercritical state (temperature above 31.1 °C, pressure above 72.9 atm) may induce metabolic shifts in the microbial communities. Furthermore, bacterial population and activity can be strongly influenced by changes in pH value, pressure, temperature, salinity and other abiotic factors, which will be all influenced by CO2 injection into the deep subsurface. Analyses of the composition of microbial communities and its changes should contribute to an evaluation of the effectiveness and reliability of the long-term CO2 storage technique. The interactions between microorganisms and the minerals of both the reservoir and the cap rock may cause major changes to the structure and chemical composition of the rock formations, which would influence the permeability within the reservoir. In addition, precipitation and corrosion may occur around the well affecting the casing and the casing cement. By using Fluorescence in situ Hybridisation (FISH) and molecular fingerprinting such as Polymerase-Chain-Reaction Single-Strand-Conformation Polymorphism (PCR-SSCP) and Denaturing

  15. Regional climate responses to geoengineering with tropical and Arctic SO2 injections

    NASA Astrophysics Data System (ADS)

    Robock, Alan; Oman, Luke; Stenchikov, Georgiy L.

    2008-08-01

    Anthropogenic stratospheric aerosol production, so as to reduce solar insolation and cool Earth, has been suggested as an emergency response to geoengineer the planet in response to global warming. While volcanic eruptions have been suggested as innocuous examples of stratospheric aerosols cooling the planet, the volcano analog actually argues against geoengineering because of ozone depletion and regional hydrologic and temperature responses. To further investigate the climate response, here we simulate the climate response to both tropical and Arctic stratospheric injection of sulfate aerosol precursors using a comprehensive atmosphere-ocean general circulation model, the National Aeronautics and Space Administration Goddard Institute for Space Studies ModelE. We inject SO2 and the model converts it to sulfate aerosols, transports the aerosols and removes them through dry and wet deposition, and calculates the climate response to the radiative forcing from the aerosols. We conduct simulations of future climate with the Intergovernmental Panel on Climate Change A1B business-as-usual scenario both with and without geoengineering and compare the results. We find that if there were a way to continuously inject SO2 into the lower stratosphere, it would produce global cooling. Tropical SO2 injection would produce sustained cooling over most of the world, with more cooling over continents. Arctic SO2 injection would not just cool the Arctic. Both tropical and Arctic SO2 injection would disrupt the Asian and African summer monsoons, reducing precipitation to the food supply for billions of people. These regional climate anomalies are but one of many reasons that argue against the implementation of this kind of geoengineering.

  16. “Vivo para consumirla y la consumo para vivir” [“I live to inject and inject to live”]: High-Risk Injection Behaviors in Tijuana, Mexico

    PubMed Central

    Strathdee, Steffanie A.; Fraga, Wendy Davila; Case, Patricia; Firestone, Michelle; Brouwer, Kimberly C.; Perez, Saida Gracia; Magis, Carlos; Fraga, Miguel Angel

    2007-01-01

    Injection drug use is a growing problem on the US–Mexico border, where Tijuana is situated. We studied the context of injection drug use among injection drug users (IDUs) in Tijuana to help guide future research and interventions. Guided in-depth interviews were conducted with 10 male and 10 female current IDUs in Tijuana. Topics included types of drug used, injection settings, access to sterile needles, and environmental influences. Interviews were taped, transcribed verbatim, and translated. Content analysis was conducted to identify themes. Of the 20 IDUs, median age and age at first injection were 30 and 18. Most reported injecting at least daily: heroin (“carga,” “chiva,” “negra”), methamphetamine (“crico,” “cri-cri”), or both drugs combined. In sharp contrast to Western US cities, almost all regularly attended shooting galleries (“yongos” or “picaderos”) because of the difficulties obtaining syringes and police oppression. Almost all shared needles/paraphernalia [“cuete” (syringe), “cacharros” (cookers), cotton from sweaters/socks (filters)]. Some reported obtaining syringes from the United States. Key themes included (1) pharmacies refusing to sell or charging higher prices to IDUs, (2) ample availability of used/rented syringes from “picaderos” (e.g., charging approximately 5 pesos or “10 drops” of drug), and (3) poor HIV/AIDS knowledge, such as beliefs that exposing syringes to air “kills germs.” This qualitative study suggests that IDUs in Tijuana are at high risk of HIV and other blood-borne infections. Interventions are urgently needed to expand access to sterile injection equipment and offset the potential for a widespread HIV epidemic. PMID:16107441

  17. High peak power gyroklystron with an inverted magnetron injection gun

    SciTech Connect

    Read, Michael E.; Lawson, Wesley; Miram, George; Marsden, David; Borchard, Philipp

    2005-12-01

    Calabazas Creek Research Inc. (CCR) has investigated the feasibility of a 30 GHz gyroklystron amplifier for driving advanced accelerators. Gyroklystrons have been shown to be efficient sources of high power radiation at frequencies above X-Band and are, therefore, well suited for driving high frequency accelerators. CCR's gyroklystron design includes a novel inverted magnetron injection gun (MIG) that allows support and cooling of the coaxial inner conductor of the circuit. This novel gun provides a very high quality electron beam, making it possible to achieve a cavity design with an efficiency of 54%. During Phase I, it was determined that the original frequency of 17 GHz was no longer well matched to the potential market. A survey of accelerator needs identified the Compact Linear Collider (CLIC) as requiring 30 GHz sources for testing of accelerator structures. Developers at CLIC are seeking approximately 25 MW per tube. This will result in the same power density as in the original 80 MW, 17 GHz device and will thus have essentially the same risk. CLIC will require initially 3-4 tubes and eventually 12-16 tubes. This quantity represents $5M-$10M in sales. In addition, gyroklystrons are of interest for radar systems and electron paramagnetic resonance (EPR) instruments. Following discussions with the Department of Energy, it was determined that changing the program goal to the CLIC requirement was in the best interest of CCR and the funding agency. The Phase I program resulted in a successful gyroklystron design with a calculated efficiency of 54% with an output power of 33 MW. Design calculations for all critical components are complete, and no significant technical issues remain.

  18. Analysis of the response of the Raft River monitor wells to the 1979 injection tests

    SciTech Connect

    Spencer, S.G.; Callan, D.M.

    1980-09-01

    The geothermal resource for the Department of Energy's (DOE) Raft River Geothermal 5 MWe Power Project is located in a closed ground water basin in southcentral Idaho. Chemical analyses indicate the existence of natural communication along fractures between the geothermal reservoir and the shallower aquifers developed for irrigation. Much of the ground water that is presently used for irrigation is of poor quality. Injection of geothermal fluids at intermediate depths may increase communication between the reservoir and the aquifer, resulting in further degradation of shallow ground water quality over time. Seven monitor wells, ranging in depth from 150 m to 400 m, were drilled to evaluate the potential for this degradation. Monitoring of these wells during two 21-day injection tests at the Raft River Geothermal Injection Well-6 (RRGI-6) indicates two types of response in the shallow aquifer system. First, the water level in Monitor Well-4 (MW-4) increased an average of 0.4 m/week during injection, indicating direct fracture connection between the injection zone and the aquifer penetrated by MW-4. Second, water levels in MW-5, MW-6, and MW-7 showed a step function decrease which coincided with the period of the injection tests. Analyses indicate that this response may be caused by elastic deformation in the aquifer matrix.

  19. Non-specific immune response of bullfrog Rana catesbeiana to intraperitoneal injection of bacterium Aeromonas hydrophila

    NASA Astrophysics Data System (ADS)

    Zhang, Junjie; Zou, Wenzheng; Yan, Qingpi

    2008-08-01

    Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups. Each bullfrog in bacterium-injected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml, while each one in control group injected i.p. with 0.2 ml sterile saline solution (0.85%, w/v). Three bullfrogs in both groups were sampled at 0, 1, 3, 7, 11, 15 and 20 days post-injection (dpi) for the evaluation of non-specific immune parameters. It was observed that intraperitoneal injection of A. hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood. Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group. However, a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes. No significant difference in changes in the number of peripheral erythrocytes, serum superoxide dismutase (SOD) activity, and lysozyme activity was detected between the two groups. It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A. hydrophila infection.

  20. Response to LPS Injection after Anti-Orthostatic Hypokinesia in Rats, an Hypothesis for Endothelial Dysfunction

    NASA Astrophysics Data System (ADS)

    Navasiolava, N. M.; Pashkevich, S. G.; Custaud, M. A.; Emelianova, A. A.; Kulchitsky, V. A.

    2008-06-01

    The indirect estimation of lipopolysaccharide (LPS) translocation by measuring of IL-6 serum level after LPS injection was carried out. We found a decreased response to LPS injection as the result of previous LPS translocation in rats after head-down tilt -45° (HDT) during 7 days and in rats after the repeated injection of LPS in 7 days after the first injection. Under electron microscopy, fringe-looking protrusions in vessel lumen, disturbance of basal membrane integrity and infringement of interendothelial junctions, adhesion of leukocytes were found in arterioles of these groups of animals. So, we suppose that translocation of LPS from gut could occur in simulated weightlessness model in rats (HDT) and could be associated with endothelial dysfunction.

  1. PERMEABILITY EVOLUTION IN A FRACTURED ROCK MASS IN RESPONSE TO FLUID INJECTION

    SciTech Connect

    Morris, J; Johnson, S

    2008-08-13

    Large-scale carbon capture and sequestration (CCS) projects involving annual injections of millions of tons of CO2 are a key infrastructural element needed to substantially reduce greenhouse gas emissions. The large rate and volume of injection will induce pressure and stress gradients within the formation that could activate existing fractures and faults, or drive new fractures through the caprock. We will present results of an ongoing investigation to identify conditions that will activate existing fractures/faults or make new fractures within the caprock using the Livermore Distinct Element Code (LDEC). LDEC is a multiphysics code, developed at LLNL, capable of simulating dynamic fracture of rock masses under a range of conditions. We will present several demonstrations of LDEC functionality and applications of LDEC to CO2 injection scenarios including injection into an extensively fractured rock-mass. These examples highlight the advantages of explicitly including the geomechanical response of each interface within the rock-mass.

  2. Planar near-nozzle velocity measurements during a single high-pressure fuel injection

    NASA Astrophysics Data System (ADS)

    Schlüßler, Raimund; Gürtler, Johannes; Czarske, Jürgen; Fischer, Andreas

    2015-09-01

    In order to reduce the fuel consumption and exhaust emissions of modern Diesel engines, the high-pressure fuel injections have to be optimized. This requires continuous, time-resolved measurements of the fuel velocity distribution during multiple complete injection cycles, which can provide a deeper understanding of the injection process. However, fuel velocity measurements at high-pressure injection nozzles are a challenging task due to the high velocities of up to 300 m/s, the short injection durations in the range and the high fuel droplet density especially near the nozzle exit. In order to solve these challenges, a fast imaging Doppler global velocimeter with laser frequency modulation (2D-FM-DGV) incorporating a high-speed camera is presented. As a result, continuous planar velocity field measurements are performed with a measurement rate of 200 kHz in the near-nozzle region of a high-pressure Diesel injection. The injection system is operated under atmospheric surrounding conditions with injection pressures up to 1400 bar thereby reaching fuel velocities up to 380 m/s. The measurements over multiple entire injection cycles resolved the spatio-temporal fluctuations of the fuel velocity, which occur especially for low injection pressures. Furthermore, a sudden setback of the velocity at the beginning of the injection is identified for various injection pressures. In conclusion, the fast measurement system enables the investigation of the complete temporal behavior of single injection cycles or a series of it. Since this eliminates the necessity of phase-locked measurements, the proposed measurement approach provides new insights for the analysis of high-pressure injections regarding unsteady phenomena.

  3. Materials for High-Pressure Fuel Injection Systems

    SciTech Connect

    Blau, P.; Shyam, A.; Hubbard, C.; Howe, J.; Trejo, R.; Yang, N.; Pollard, M.

    2011-09-30

    The high-level goal of this multi-year effort was to facilitate the Advanced Combustion Engine goal of 20% improvement (compared to 2009 baseline) of commercial engine efficiency by 2015. A sub-goal is to increase the reliability of diesel fuel injectors by investigating modelbased scenarios that cannot be achieved by empirical, trial and error methodologies alone. During this three-year project, ORNL developed the methodology to evaluate origins and to record the initiation and propagation of fatigue cracks emanating from holes that were electrodischarge machined (EDM), the method used to form spray holes in fuel injector tips. Both x-ray and neutron-based methods for measuring residual stress at four different research facilities were evaluated to determine which, if any, was most applicable to the fuel injector tip geometry. Owing to the shape and small volumes of material involved in the sack area, residual stress data could only be obtained in the walls of the nozzle a few millimeters back from the tip, and there was a hint of only a small compressive stress. This result was consistent with prior studies by Caterpillar. Residual stress studies were suspended after the second year, reserving the possibility of pursuing this in the future, if and when methodology suitable for injector sacks becomes available. The smooth specimen fatigue behavior of current fuel injector steel materials was evaluated and displayed a dual mode initiation behavior. At high stresses, cracks started at machining flaws in the surface; however, below a critical threshold stress of approximately 800 MPa, cracks initiated in the bulk microstructure, below the surface. This suggests that for the next generation for high-pressure fuel injector nozzles, it becomes increasingly important to control the machining and finishing processes, especially if the stress in the tip approaches or exceeds that threshold level. Fatigue tests were also conducted using EDM notches in the gage sections

  4. The role of dorsomedial hypotalamus ionotropic glutamate receptors in the hypertensive and tachycardic responses evoked by Tityustoxin intracerebroventricular injection.

    PubMed

    Silva, F C; Guidine, Patrícia Alves Maia; Machado, Natalia Lima; Xavier, Carlos Henrique; de Menezes, R C; Moraes-Santos, Tasso; Moraes, Márcio Flávio; Chianca, Deoclécio Alves

    2015-03-01

    The scorpion envenoming syndrome is an important worldwide public health problem due to its high incidence and potential severity of symptoms. Some studies address the high sensitivity of the central nervous system to this toxin action. It is known that cardiorespiratory manifestations involve the activation of the autonomic nervous system. However, the origin of this modulation remains unclear. Considering the important participation of the dorsomedial hypotalamus (DMH) in the cardiovascular responses during emergencial situations, the aim of this work is to investigate the involvement of the DMH on cardiovascular responses induced by intracerebroventricular (icv) injection of Tityustoxin (TsTX, a α-type toxin extracted from the Tityus serrulatus scorpion venom). Urethane-anaesthetized male Wistar rats (n=30) were treated with PBS, muscimol or ionotropic glutamate receptor antagonists, bilaterally in DMH and later, with an icv injection of TsTX, or treated only with PBS in both regions. TsTX evoked a marked increase in mean arterial pressure and heart rate in all control rats. Interestingly, injection of muscimol, a GABAA receptor agonist, did not change the pressor and tachycardic responses evoked by TsTX. Remarkably, the injection ionotropic glutamate receptors antagonists in DMH abolished the pressor and the tachycardic response evoked by TsTX. Our data suggest that the central circuit recruited by TsTX, whose activation results in an array of physiological and behavioral alterations, depend on the activation of DMH ionotropic glutamate receptors. Moreover, our data provide new insights on the central mechanisms involved in the development of symptoms in the severe scorpion envenomation syndrome. PMID:25616225

  5. Transient response in a dendritic neuron model for current injected at one branch.

    PubMed

    Rinzel, J; Rall, W

    1974-10-01

    Mathematical expressions are obtained for the response function corresponding to an instantaneous pulse of current injected to a single dendritic branch in a branched dendritic neuron model. The theoretical model assumes passive membrane properties and the equivalent cylinder constraint on branch diameters. The response function when used in a convolution formula enables one to compute the voltage transient at any specified point in the dendritic tree for an arbitrary current injection at a given input location. A particular numerical example, for a brief current injection at a branch terminal, illustrates the attenuation and delay characteristics of the depolarization peak as it spreads throughout the neuron model. In contrast to the severe attenuation of voltage transients from branch input sites to the soma, the fraction of total input charge actually delivered to the soma and other trees is calculated to be about one-half. This fraction is independent of the input time course. Other numerical examples, which compare a branch terminal input site with a soma input site, demonstrate that, for a given transient current injection, the peak depolarization is not proportional to the input resistance at the injection site and, for a given synaptic conductance transient, the effective synaptic driving potential can be significantly reduced, resulting in less synaptic current flow and charge, for a branch input site. Also, for the synaptic case, the two inputs are compared on the basis of the excitatory post-synaptic potential (EPSP) seen at the soma and the total charge delivered to the soma. PMID:4424185

  6. Characterization of a folate-induced hypermotility response after bilateral injection into the rat nucleus accumbens

    SciTech Connect

    Stephens, R.L. Jr.

    1986-01-01

    The objective of these studies was to pharmacologically characterize the mechanism responsible for a folate-induced stimulation of locomotor activity in rats after bilateral injection into the nucleus accumbens region of the brain. Folic acid (FA) and 5-formyltetrahydrofolic acid (FTHF) produced this hypermotility response after intra-accumbens injection, while other reduced folic acid derivatives dihydrofolic acid, tetrahydrofolic acid, and 5-methyltetrahydrofolic acid were ineffective. Studies were designed to determine the role of catecholamines in the nucleus accumbens in the folate-induced hypermotility response. The findings suggest that the folate-induced response is dependent on intact neuronal dopamine stores, and is mediated by stimulation of dopamine receptors of the nucleus accumbens. However the folates do not appear to enhance dopaminergic neutransmission. Thus, FA and FTHF were inefficient at 1 mM concentrations in stimulating /sup 3/H-dopamine release from /sup 3/H-dopamine preloaded nucleus accumbens slices or dopamine from endogenous stores. Pteroic acid, the chemical precursor of folic acid which lacks the glutamate moiety, was ineffective in producing a stimulation of locomotor activity after intra-accumbens injection. Since glutamate is an excitatory amino acid (EAA), compounds characterized as EAA receptor antagonists were utilized to determine if the folate-induced hypermotility response is mediated by activation of EAA receptors in the nucleus accumbens. These results suggest that activation of quisqualate receptors of the nucleus accumbens may mediate the folate-induced hypermotility response.

  7. Dynamics of ionization-induced electron injection in the high density regime of laser wakefield acceleration

    SciTech Connect

    Desforges, F. G.; Paradkar, B. S. Ju, J.; Audet, T. L.; Maynard, G.; Cros, B.; Hansson, M.; Senje, L.; Persson, A.; Lundh, O.; Wahlström, C.-G.; Dobosz-Dufrénoy, S.; Monot, P.; Vay, J.-L.

    2014-12-15

    The dynamics of ionization-induced electron injection in high density (∼1.2 × 10{sup 19} cm{sup −3}) regime of laser wakefield acceleration is investigated by analyzing the betatron X-ray emission. In such high density operation, the laser normalized vector potential exceeds the injection-thresholds of both ionization-injection and self-injection due to self-focusing. In this regime, direct experimental evidence of early on-set of ionization-induced injection into the plasma wave is given by mapping the X-ray emission zone inside the plasma. Particle-In-Cell simulations show that this early on-set of ionization-induced injection, due to its lower trapping threshold, suppresses the trapping of self-injected electrons. A comparative study of the electron and X-ray properties is performed for both self-injection and ionization-induced injection. An increase of X-ray fluence by at least a factor of two is observed in the case of ionization-induced injection due to increased trapped charge compared to self-injection mechanism.

  8. Automating fruit fly Drosophila embryo injection for high throughput transgenic studies

    NASA Astrophysics Data System (ADS)

    Cornell, E.; Fisher, W. W.; Nordmeyer, R.; Yegian, D.; Dong, M.; Biggin, M. D.; Celniker, S. E.; Jin, J.

    2008-01-01

    To decipher and manipulate the 14 000 identified Drosophila genes, there is a need to inject a large number of embryos with transgenes. We have developed an automated instrument for high throughput injection of Drosophila embryos. It was built on an inverted microscope, equipped with a motorized xy stage, autofocus, a charge coupled device camera, and an injection needle mounted on a high speed vertical stage. A novel, micromachined embryo alignment device was developed to facilitate the arrangement of a large number of eggs. The control system included intelligent and dynamic imaging and analysis software and an embryo injection algorithm imitating a human operator. Once the injection needle and embryo slide are loaded, the software automatically images and characterizes each embryo and subsequently injects DNA into all suitable embryos. The ability to program needle flushing and monitor needle status after each injection ensures reliable delivery of biomaterials. Using this instrument, we performed a set of transformation injection experiments. The robot achieved injection speeds and transformation efficiencies comparable to those of a skilled human injector. Because it can be programed to allow injection at various locations in the embryo, such as the anterior pole or along the dorsal or ventral axes, this system is also suitable for injection of general biochemicals, including drugs and RNAi.

  9. A thermally responsive injectable hydrogel incorporating methacrylate-polylactide for hydrolytic lability

    PubMed Central

    Ma, Zuwei; Nelson, Devin M.; Hong, Yi; Wagner, William R.

    2011-01-01

    Injectable thermoresponsive hydrogels are of interest for a variety of biomedical applications, including regional tissue mechanical support as well as drug and cell delivery. Within this class of materials there is a need to provide options for gels with stronger mechanical properties as well as variable degradation profiles. To address this need, the hydrolytically labile monomer, methacrylate-polylactide (MAPLA), with an average 2.8 lactic acid units, was synthesized and copolymerized with N-isopropylacrylamide (NIPAAm) and 2-hydroxyethyl methacrylate (HEMA) to obtain bioabsorbable thermally responsive hydrogels. Poly(NIPAAm-co-HEMA-co-MAPLA) with three monomer feed ratios (84/10/6, 82/10/8 and 80/10/10) was synthesized and characterized with NMR, FTIR and GPC. The copolymers were soluble in saline at reduced temperature (<10°C), forming clear solutions that increased in viscosity with the MAPLA feed ratio. The copolymers underwent sol-gel transition at lower critical solution temperatures of 12.4, 14.0 and 16.2°C respectively and solidified immediately upon being placed in a 37°C water bath. The warmed hydrogels gradually excluded water to reach final water contents of ~45%. The hydrogels as formed were mechanically strong, with tensile strengths as high as 100 kPa and shear moduli of 60 kPa. All three hydrogels were completely degraded (solubilized) in PBS over a 6–8 month period at 37°C, with a higher MAPLA feed ratio resulting in a faster degradation period. Culture of primary vascular smooth muscle cells with degradation solutions demonstrated a lack of cytotoxicity. The synthesized hydrogels provide new options for biomaterial injection therapy where increased mechanical strength and relatively slow resorption rates would be attractive. PMID:20575552

  10. Gas-injection valve operates at high speed

    NASA Technical Reports Server (NTRS)

    Hoh, F. C.; Lowder, R. S.

    1966-01-01

    Fast acting gas valve is used for injecting a short pulse of gas into a vacuum chamber during plasma acceleration experiments. It contains a lightweight closure disk that is forced away from the valve seat when an electromagnetic coil is momentarily energized and immediately rebounds from a stop back onto the seat.

  11. Highly efficient 6-stroke engine cycle with water injection

    SciTech Connect

    Szybist, James P; Conklin, James C

    2012-10-23

    A six-stroke engine cycle having improved efficiency. Heat is recovered from the engine combustion gases by using a 6-stroke engine cycle in which combustion gases are partially vented proximate the bottom-dead-center position of the fourth stroke cycle, and water is injected proximate the top-dead-center position of the fourth stroke cycle.

  12. Picosecond ballistic imaging of diesel injection in high-temperature and high-pressure air

    NASA Astrophysics Data System (ADS)

    Duran, Sean P.; Porter, Jason M.; Parker, Terence E.

    2015-04-01

    The first successful demonstration of picosecond ballistic imaging using a 15-ps-pulse-duration laser in diesel sprays at temperature and pressure is reported. This technique uses an optical Kerr effect shutter constructed from a CS2 liquid cell and a 15-ps pulse at 532 nm. The optical shutter can be adjusted to produce effective imaging pulses between 7 and 16 ps. This technique is used to image the near-orifice region (first 3 mm) of diesel sprays from a high-pressure single-hole fuel injector. Ballistic imaging of dodecane and methyl oleate sprays injected into ambient air and diesel injection at preignition engine-like conditions are reported. Dodecane was injected into air heated to 600 °C and pressurized to 20 atm. The resulting images of the near-orifice region at these conditions reveal dramatic shedding of the liquid near the nozzle, an effect that has been predicted, but to our knowledge never before imaged. These shedding structures have an approximate spatial frequency of 10 mm-1 with lengths from 50 to 200 μm. Several parameters are explored including injection pressure, liquid fuel temperature, air temperature and pressure, and fuel type. Resulting trends are summarized with accompanying images.

  13. Injectable and pH-Responsive Silk Nanofiber Hydrogels for Sustained Anticancer Drug Delivery.

    PubMed

    Wu, Hongchun; Liu, Shanshan; Xiao, Liying; Dong, Xiaodan; Lu, Qiang; Kaplan, David L

    2016-07-13

    Silk is useful as a drug carrier due to its biocompatibility, tunable degradation, and outstanding capacity in maintaining the function of drugs. Injectable silk hydrogels could deliver doxorubicin (DOX) for localized chemotherapy for breast cancer. To improve hydrogel properties, thixotropic silk nanofiber hydrogels in an all-aqueous solution were prepared and used to locally deliver DOX. The silk hydrogels displayed thixotropic capacity, allowing for easy injectability followed by solidification in situ. The hydrogels were loaded with DOX and released the drug over eight weeks with pH- and concentration-dependent release kinetics. In vitro and in vivo studies demonstrated that DOX-loaded silk hydrogels had good antitumor response, outperforming the equivalent dose of free DOX administered intravenously. Thixotropic silk hydrogels provide improved injectability to support sustained release, suggesting promising applications for localized chemotherapy. PMID:27315327

  14. Engine with hydraulic fuel injection and ABS circuit using a single high pressure pump

    DOEpatents

    Bartley, Bradley E.; Blass, James R.; Gibson, Dennis H.

    2001-01-01

    An engine system comprises a hydraulically actuated fuel injection system and an ABS circuit connected via a fluid flow passage that provides hydraulic fluid to both the fuel injection system and to the ABS circuit. The hydraulically actuated system includes a high pressure pump. The fluid control passage is in fluid communication with an outlet from the high pressure pump.

  15. High power continuous wave injection-locked solid state laser

    SciTech Connect

    Nabors, C.D.; Byer, R.L.

    1991-06-25

    This patent describes an injection locked laser system. It comprises a master laser, the master laser including a solid state gain medium and having a continuous wave, single frequency output; a slave laser including a solid state gain medium located in a resonant cavity and having a continuous wave output at a power at least ten times greater than the master laser, with the output of the master laser being injected into the slave laser in order to cause the slave laser to oscillate at the same frequency as the output of the master laser; and means for actively stabilizing the slave laser so that its output frequency remains locked with the output frequency of the master laser.

  16. High Peak Power Gyroklystron with an Inverted Magnetron Injection Gun

    NASA Astrophysics Data System (ADS)

    Read, Michael; Neilson, Jeff; Borchard, Philipp; Ives, Lawrence; Lawson, Wes

    2006-01-01

    This paper describes the design of a 25 MW, 30 GHz gyroklystron amplifier based on a coaxial RF structure. The design includes an inverted magnetron injection gun (MIG) for positioning and cooling the inner conductor. The gun produces a very low spread beam that contributes to a device efficiency of 54%. Details are given of the gun, RF structure, input and output couplers and collector.

  17. Robotic injection of zebrafish embryos for high-throughput screening in disease models.

    PubMed

    Spaink, Herman P; Cui, Chao; Wiweger, Malgorzata I; Jansen, Hans J; Veneman, Wouter J; Marín-Juez, Rubén; de Sonneville, Jan; Ordas, Anita; Torraca, Vincenzo; van der Ent, Wietske; Leenders, William P; Meijer, Annemarie H; Snaar-Jagalska, B Ewa; Dirks, Ron P

    2013-08-15

    The increasing use of zebrafish larvae for biomedical research applications is resulting in versatile models for a variety of human diseases. These models exploit the optical transparency of zebrafish larvae and the availability of a large genetic tool box. Here we present detailed protocols for the robotic injection of zebrafish embryos at very high accuracy with a speed of up to 2000 embryos per hour. These protocols are benchmarked for several applications: (1) the injection of DNA for obtaining transgenic animals, (2) the injection of antisense morpholinos that can be used for gene knock-down, (3) the injection of microbes for studying infectious disease, and (4) the injection of human cancer cells as a model for tumor progression. We show examples of how the injected embryos can be screened at high-throughput level using fluorescence analysis. Our methods open up new avenues for the use of zebrafish larvae for large compound screens in the search for new medicines. PMID:23769806

  18. Intratumoral injection of Clostridium novyi-NT spores induces antitumor responses

    PubMed Central

    Rusk, Anthony W.; Tung, David; Miller, Maria; Roix, Jeffrey; Khanna, Kristen V.; Murthy, Ravi; Benjamin, Robert S.; Helgason, Thorunn; Szvalb, Ariel D.; Bird, Justin E.; Roy-Chowdhuri, Sinchita; Zhang, Halle H.; Qiao, Yuan; Karim, Baktiar; McDaniel, Jennifer; Elpiner, Amanda; Sahora, Alexandra; Lachowicz, Joshua; Phillips, Brenda; Turner, Avenelle; Klein, Mary K.; Post, Gerald; Diaz, Luis A.; Riggins, Gregory J.; Papadopoulos, Nickolas; Kinzler, Kenneth W.; Vogelstein, Bert; Bettegowda, Chetan; Huso, David L.; Varterasian, Mary

    2015-01-01

    Species of Clostridium bacteria are notable for their ability to lyse tumor cells growing in hypoxic environments. We show that an attenuated strain of Clostridium novyi (C. novyi-NT) induces a microscopically precise, tumor-localized response in a rat orthotopic brain tumor model after intratumoral injection. It is well known, however, that experimental models often do not reliably predict the responses of human patients to therapeutic agents. We therefore used naturally occurring canine tumors as a translational bridge to human trials. Canine tumors are more like those of humans because they occur in animals with heterogeneous genetic backgrounds, are of host origin, and are due to spontaneous rather than engineered mutations. We found that intratumoral injection of C. novyi-NT spores was well tolerated in companion dogs bearing spontaneous solid tumors, with the most common toxicities being the expected symptoms associated with bacterial infections. Objective responses were observed in 6 of 16 dogs (37.5%), with three complete and three partial responses. On the basis of these encouraging results, we treated a human patient who had an advanced leiomyosarcoma with an intratumoral injection of C. novyi-NT spores. This treatment reduced the tumor within and surrounding the bone. Together, these results show that C. novyi-NT can precisely eradicate neoplastic tissues and suggest that further clinical trials of this agent in selected patients are warranted. PMID:25122639

  19. Intratumoral injection of Clostridium novyi-NT spores induces antitumor responses.

    PubMed

    Roberts, Nicholas J; Zhang, Linping; Janku, Filip; Collins, Amanda; Bai, Ren-Yuan; Staedtke, Verena; Rusk, Anthony W; Tung, David; Miller, Maria; Roix, Jeffrey; Khanna, Kristen V; Murthy, Ravi; Benjamin, Robert S; Helgason, Thorunn; Szvalb, Ariel D; Bird, Justin E; Roy-Chowdhuri, Sinchita; Zhang, Halle H; Qiao, Yuan; Karim, Baktiar; McDaniel, Jennifer; Elpiner, Amanda; Sahora, Alexandra; Lachowicz, Joshua; Phillips, Brenda; Turner, Avenelle; Klein, Mary K; Post, Gerald; Diaz, Luis A; Riggins, Gregory J; Papadopoulos, Nickolas; Kinzler, Kenneth W; Vogelstein, Bert; Bettegowda, Chetan; Huso, David L; Varterasian, Mary; Saha, Saurabh; Zhou, Shibin

    2014-08-13

    Species of Clostridium bacteria are notable for their ability to lyse tumor cells growing in hypoxic environments. We show that an attenuated strain of Clostridium novyi (C. novyi-NT) induces a microscopically precise, tumor-localized response in a rat orthotopic brain tumor model after intratumoral injection. It is well known, however, that experimental models often do not reliably predict the responses of human patients to therapeutic agents. We therefore used naturally occurring canine tumors as a translational bridge to human trials. Canine tumors are more like those of humans because they occur in animals with heterogeneous genetic backgrounds, are of host origin, and are due to spontaneous rather than engineered mutations. We found that intratumoral injection of C. novyi-NT spores was well tolerated in companion dogs bearing spontaneous solid tumors, with the most common toxicities being the expected symptoms associated with bacterial infections. Objective responses were observed in 6 of 16 dogs (37.5%), with three complete and three partial responses. On the basis of these encouraging results, we treated a human patient who had an advanced leiomyosarcoma with an intratumoral injection of C. novyi-NT spores. This treatment reduced the tumor within and surrounding the bone. Together, these results show that C. novyi-NT can precisely eradicate neoplastic tissues and suggest that further clinical trials of this agent in selected patients are warranted. PMID:25122639

  20. Correlation of Foraminal Area and Response to Cervical Nerve Root Injections

    PubMed Central

    Ray, Wilson Z; Akbari, Syed; Shah, Lubdha M

    2015-01-01

    Introduction: Patients with age-related degenerative changes in the cervical spine leading to cervical spondylosis may be symptomatic or asymptomatic. Older patients with radicular pain tend to have a better response to epidural steroid injections, but it is often difficult to predict which patients will have a positive response to selective nerve root block (SNRB). We analyzed whether the cervical neuroforaminal area measured on MRI predicts immediate therapeutic responses to SNRB in patients who have cervical radiculopathy. Methods: We retrospectively reviewed all patients who had cervical SNRBs treated at a single tertiary referral center. We recorded patient demographics, the neuroforaminal area of the symptomatic and contralateral sides, Visual Analog Scale (VAS) score pre- and post-injection, history of previous cervical surgery, comorbidities, and history of tobacco use. Results: Sixty-four patients with symptoms of cervical radiculopathy treated with neuroforaminal nerve root injections had appropriate imaging and VAS scores recorded. The average foraminal area of the symptomatic side before treatment was significantly smaller than the contralateral asymptomatic neuroforamen (p<0.0001). Those patients with the smallest neuroforamen had a positive response to SNRB. Diabetes and tobacco use did not influence patient response to treatment. Conclusions: Measurement of neuroforaminal areas on MRI may represent a useful pre-procedural technique to predict which patients with symptoms of cervical radiculopathy secondary to foraminal stenosis are likely to respond to selective nerve root injections. The predictive ability appears to be limited to those patients with severe stenosis and was less useful in those patients with moderate or mild stenosis. PMID:26203404

  1. Cellular responses of the tiger shrimp Penaeus monodon haemocytes after lipopolysaccharide injection.

    PubMed

    Xian, Jian-An; Zhang, Xiu-Xia; Guo, Hui; Wang, Dong-Mei; Wang, An-Li

    2016-07-01

    This study was aimed at investigating the in vivo effects of lipopolysaccharide (LPS) injection on Penaeus monodon haemocytes at a cellular level. Cellular responses of LPS-injected shrimp were analysed using flow cytometry. Results showed that LPS injection caused total haemocyte count (THC) and count of large cells (semigranular and granular cells) decline. In LPS-injected shrimp, percentage of large cells decreased at the initial stage, and returned to the original level later. After LPS infection, non-specific esterase activity, reactive oxygen species (ROS) production and nitric oxide (NO) production in haemocytes were significantly induced, while apoptotic cell ratio of haemocytes increased. PO activity in plasma increased in shrimp received LPS at 2 μg g(-1) after 3-12 h and at 8 μg g(-1) after 3-6 h, and then returned to the initial levels. These results demonstrated that LPS induced immune responses on haemocytes, including production of ROS and NO, and release of esterase and PO. On the other hand, THC reduction might be due to the ROS/NO-induced apoptosis. Haemocyte apoptosis which would eliminate damaged or weak cells and contribute to haemocyte renewal, may be a defending strategie against pathogens. PMID:27134076

  2. Liposomal Bupivacaine as a Single-Injection Peripheral Nerve Block: A Dose-Response Study

    PubMed Central

    Ilfeld, Brian M.; Malhotra, Nisha; Furnish, Timothy J.; Donohue, Michael C.; Madison, Sarah J.

    2013-01-01

    Background Currently available local anesthetics approved for single-injection peripheral nerve blocks have a maximum duration less than 24 hours. A liposomal bupivacaine formulation (EXPAREL®, Pacira Pharmaceuticals, Inc., San Diego, California), releasing bupivacaine over 96 hours, recently gained Food and Drug Administration approval exclusively for wound infiltration, but not peripheral nerve blocks. Methods Bilateral single-injection femoral nerve blocks were administered in healthy volunteers (n=14). For each block, liposomal bupivacaine (0–80 mg) was mixed with normal saline to produce 30 mL of study fluid. Each subject received two different doses, one on each side, applied randomly in a double-masked fashion. The end points included the maximum voluntary isometric contraction (MVIC) of the quadriceps femoris muscle and tolerance to cutaneous electrical current in the femoral nerve distribution. Measurements were performed from baseline until quadriceps MVIC returned to 80% of baseline bilaterally. Results There were statistically significant dose responses in MVIC (0.09% / mg, SE = 0.03, 95% CI 0.04 to 0.14, p = 0.002) and tolerance to cutaneous current (−0.03 mA / mg, SE = 0.01, 95% CI −0.04 to 0.02, p < 0.001), however, in the opposite direction than expected (the higher the dose, the lower the observed effect). This inverse relationship is biologically implausible, and most likely due to the limited sample size and the subjective nature of the measurement instruments. While peak effects occurred within 24 hours after block administration in 75% of cases (95% CI 43 to 93%), block duration usually lasted much longer: for bupivacaine doses above 40 mg, tolerance to cutaneous current did not return to within 20% above baseline until after 24 h in 100% of subjects (95% CI 56 to 100). MVIC did not consistently return to within 20% of baseline until after 24 hours in 90% of subjects (95% CI 54 to 100%). Motor block duration was not correlated with

  3. Spider leg autotomy induced by prey venom injection: An adaptive response to “pain”?*

    PubMed Central

    Eisner, Thomas; Camazine, Scott

    1983-01-01

    Field observations showed orb-weaving spiders (Argiope spp.) to undergo leg autotomy if they are stung in a leg by venomous insect prey (Phymata fasciata). The response occurs within seconds, before the venom can take lethal action by spread to the body of the spiders. Autotomy is induced also by honeybee venom and wasp venom, as well as by several venom components (serotonin, histamine, phospholipase A2, melittin) known to be responsible for the pain characteristically elicited by venom injection in humans. The sensing mechanism by which spiders detect injected harmful chemicals such as venoms therefore may be fundamentally similar to the one in humans that is coupled with the perception of pain. Images PMID:16593325

  4. A repeated injection of polyethyleneglycol-conjugated recombinant human butyrylcholinesterase elicits immune response in mice

    SciTech Connect

    Chilukuri, Nageswararao Sun Wei; Parikh, Kalpana; Naik, Ramachandra S.; Tang Lin; Doctor, Bhupendra P.; Saxena, Ashima

    2008-09-15

    Human serum butyrylcholinesterase (Hu BChE) serves as an efficacious bioscavenger of highly toxic organophosphorus (OP) compounds. Since there is a concern that the supply of native Hu BChE may be limited, monomeric and tetrameric forms of recombinant Hu BChE (rHu BChE) were evaluated as replacements and found that they lacked sufficient stability in vivo. However, their in vivo stability could be significantly prolonged by conjugation with polyethyleneglycol-20K (PEG) suggesting that monomeric and tetrameric PEG-rHu BChE could function as bioscavengers. Here, the immunogenicity of PEG-rHu BChE was evaluated in mice following two injections given four weeks apart. In addition to pharmacokinetic parameters, such as mean residence time, maximal concentration, time to reach the maximal concentration, elimination half-life and area under the plasma concentration-time curve extrapolated to infinity, the presence of circulating anti-rHu BChE antibodies was also determined. Although the pharmacokinetic parameters were significantly improved for the first injection of monomeric and tetrameric PEG-rHu BChEs, they were much lower for the second injection. Anti-rHu BChE antibodies were detected in the blood of mice following the first and second enzyme injections and their levels were approximately higher by 5-fold and 2-fold in mice injected with monomeric and tetrameric PEG-rHu BChEs as compared to mice injected with unconjugated enzymes. The findings that the rapid clearance of a repeat injection of PEG-rHu BChEs in mice which coincides with the presence of circulating anti-rHu BChE antibodies suggest that PEG conjugation prolonged the circulatory stability of rHu BChE but failed to eliminate its immunogenicity in mice.

  5. Characterization of the Treg Response in the Hepatitis B Virus Hydrodynamic Injection Mouse Model

    PubMed Central

    Dietze, Kirsten K.; Schimmer, Simone; Kretzmer, Freya; Wang, Junzhong; Lin, Yong; Huang, Xuan; Wu, Weimin; Wang, Baoju; Lu, Mengji

    2016-01-01

    Regulatory T cells (Tregs) play an important role in counter-regulating effector T cell responses in many infectious diseases. However, they can also contribute to the development of T cell dysfunction and pathogen persistence in chronic infections. Tregs have been reported to suppress virus-specific T cell responses in hepatitis B virus (HBV) infection of human patients as well as in HBV animal models. However, the phenotype and expansion of Tregs has so far only been investigated in other infections, but not in HBV. We therefore performed hydrodynamic injections of HBV plasmids into mice and analyzed the Treg response in the spleen and liver. Absolute Treg numbers significantly increased in the liver but not the spleen after HBV injection. The cells were natural Tregs that surprisingly did not show any activation or proliferation in response to the infection. However, they were able to suppress effector T cell responses, as selective depletion of Tregs significantly increased HBV-specific CD8+ T cell responses and accelerated viral antigen clearance. The data implies that natural Tregs infiltrate the liver in HBV infection without further activation or expansion but are still able to interfere with T cell mediated viral clearance. PMID:26986976

  6. Characterization of the Treg Response in the Hepatitis B Virus Hydrodynamic Injection Mouse Model.

    PubMed

    Dietze, Kirsten K; Schimmer, Simone; Kretzmer, Freya; Wang, Junzhong; Lin, Yong; Huang, Xuan; Wu, Weimin; Wang, Baoju; Lu, Mengji; Dittmer, Ulf; Yang, Dongliang; Liu, Jia

    2016-01-01

    Regulatory T cells (Tregs) play an important role in counter-regulating effector T cell responses in many infectious diseases. However, they can also contribute to the development of T cell dysfunction and pathogen persistence in chronic infections. Tregs have been reported to suppress virus-specific T cell responses in hepatitis B virus (HBV) infection of human patients as well as in HBV animal models. However, the phenotype and expansion of Tregs has so far only been investigated in other infections, but not in HBV. We therefore performed hydrodynamic injections of HBV plasmids into mice and analyzed the Treg response in the spleen and liver. Absolute Treg numbers significantly increased in the liver but not the spleen after HBV injection. The cells were natural Tregs that surprisingly did not show any activation or proliferation in response to the infection. However, they were able to suppress effector T cell responses, as selective depletion of Tregs significantly increased HBV-specific CD8+ T cell responses and accelerated viral antigen clearance. The data implies that natural Tregs infiltrate the liver in HBV infection without further activation or expansion but are still able to interfere with T cell mediated viral clearance. PMID:26986976

  7. Cardiovascular activity in blood-injection-injury phobia during exposure: evidence for diphasic response patterns?

    PubMed

    Ritz, Thomas; Meuret, Alicia E; Simon, Erica

    2013-08-01

    Exposure to feared stimuli in blood-injection-injury (BII)-phobia is thought to elicit a diphasic response pattern, with an initial fight-flight-like cardiovascular activation followed by a marked deactivation and possible fainting (vasovagal syncope). However, studies have remained equivocal on the importance of such patterns. We therefore sought to determine the prevalence and clinical relevance of diphasic responses using criteria that require a true diphasic response to exceed cardiovascular activation of an emotional episode of a negative valence and to exceed deactivation of an emotionally neutral episode. Sixty BII-phobia participants and 20 healthy controls were exposed to surgery, anger and neutral films while measuring heart rate, blood pressure, respiratory pattern, and end-tidal partial pressure of carbon dioxide (as indicator of hyperventilation). Diphasic response patterns were observed in up to 20% of BII-phobia participants and 26.6% of healthy controls for individual cardiovascular parameters. BII-phobia participants with diphasic patterns across multiple parameters showed more fear of injections and blood draws, reported the strongest physical symptoms during the surgery film, and showed the strongest tendency to hyperventilate. Thus, although only a minority of individuals with BII phobia shows diphasic responses, their occurrence indicates significant distress. Respiratory training may add to the treatment of BII phobia patients that show diphasic response patterns. PMID:23747585

  8. Factors influencing adverse skin responses in rats receiving repeated subcutaneous injections and potential impact on neurobehavior

    PubMed Central

    Levoe, S. Nikki; Flannery, Brenna M.; Brignolo, Laurie; Imai, Denise M.; Koehne, Amanda; Austin, Adam T.; Bruun, Donald A.; Tancredi, Daniel J.; Lein, Pamela J.

    2015-01-01

    Repeated subcutaneous (s.c.) injection is a common route of administration in chronic studies of neuroactive compounds. However, in a pilot study we noted a significant incidence of skin abnormalities in adult male Long-Evans rats receiving daily s.c. injections of peanut oil (1.0 ml/kg) in the subscapular region for 21 d. Histopathological analyses of the lesions were consistent with a foreign body reaction. Subsequent studies were conducted to determine factors that influenced the incidence or severity of skin abnormalities, and whether these adverse skin reactions influenced a specific neurobehavioral outcome. Rats injected daily for 21 d with food grade peanut oil had an earlier onset and greater incidence of skin abnormalities relative to rats receiving an equal volume (1.0 ml/kg/d) of reagent grade peanut oil or triglyceride of coconut oil. Skin abnormalities in animals injected daily with peanut oil were increased in animals housed on corncob versus paper bedding. Comparison of animals obtained from different barrier facilities exposed to the same injection paradigm (reagent grade peanut oil, 1.0 ml/kg/d s.c.) revealed significant differences in the severity of skin abnormalities. However, animals from different barrier facilities did not perform differently in a Pavlovian fear conditioning task. Collectively, these data suggest that environmental factors influence the incidence and severity of skin abnormalities following repeated s.c. injections, but that these adverse skin responses do not significantly influence performance in at least one test of learning and memory. PMID:25705100

  9. High power all-fiber amplifier with different seed power injection.

    PubMed

    Wang, Jianming; Yan, Dapeng; Xiong, Songsong; Huang, Bao; Li, Cheng

    2016-06-27

    We report a high power all-fiber amplifier with suitable seed power injected by an all-fiber laser. Different seed powers were injected into the all-fiber amplifier during our amplification experiments, and we found the stimulated Raman scattering (SRS) threshold was inversely proportional to the injected seed power. More than 3 kW signal light with good beam quality (M2 = 1.28) has been obtained with a suitable seed power injected, and the slope efficiency of the all-fiber amplifier was about 84.4%. PMID:27410599

  10. Electron Injection in Laser Plasma Accelerators by High-Order Field Ionization

    SciTech Connect

    Chen, M.; Esarey, E.; Geddes, C. G. R.; Schroeder, C. B.; Leemans, W. P.

    2010-11-04

    Electron injection and trapping in a laser wakefield accelerator by high-order field ionization is studied theoretically and by particle-in-cell simulations. To obtain low energy spread beams we use a short region of gas mixture (H+N) near the start of the stage to trap electrons, while the remainder of the stage uses pure H and is injection-free. Effects of gas mix parameters, such as concentration and length, on the final electron injection number and beam quality are studied. Laser polarization and shape effects on injection number and final electron emittance are also shown.

  11. Bolus injection of human UII in conscious rats evokes a biphasic haemodynamic response.

    PubMed

    Gardiner, Sheila M; March, Julie E; Kemp, Philip A; Bennett, Terence

    2004-10-01

    A biphasic cardiovascular response to bolus i.v. injection of human urotensin II (hUII, 3 nmol kg(-1)) in conscious, male, Sprague-Dawley (SD) rats was identified and underlying mechanisms were explored. Initially (0-5 min) there was tachycardia, hypotension and mesenteric and hindquarters vasodilatation; later (30-120 min), tachycardia, hindquarters vasodilatation and a modest rise in blood pressure occurred. Pretreatment with indomethacin or N(G) nitro-l-arginine methylester (l-NAME) reduced the mesenteric vasodilator response to hUII, and abolished the late tachycardia and hindquarters vasodilatation. Indomethacin also abolished the hypotension and early hindquarters vasodilatation, and substantially reduced the initial tachycardia. Indomethacin and l-NAME together prevented all haemodynamic responses to hUII. Inhibition of inducible NOS had no effect on responses to hUII, whereas inhibition of neuronal NOS reduced the delayed tachycardic response to hUII but did not significantly affect the vasodilatation. Only the initial tachycardic response to hUII was antagonised by propranolol. In spontaneously hypertensive rats (SHR), the initial haemodynamic responses to hUII were qualitatively similar to those in SD rats, although there was also a modest renal vasodilatation. The secondary response comprised a smaller tachycardia and a small rise in blood pressure, with no significant hindquarters vasodilatation. Haemodynamic responses to hUII were not enhanced by endothelin and angiotensin receptor antagonism in either SD rats or in SHRs. One interpretation of these results is that the primary response to bolus injection of hUII is prostanoid- or prostanoid- and NO-mediated (mesenteric vasodilatation) and that this triggers secondary events, which are dependent on eNOS (hindquarters vasodilatation) and neuronal NOS (tachycardia). PMID:15339862

  12. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor fueling

    SciTech Connect

    Kim, K.; Zhang, J.

    1992-01-01

    Three separate papers are included which report research progress during this period: (1) A new railgun configuration with perforated sidewalls, (2) development of a fuseless small-bore railgun for injection of high-speed hydrogen pellets into magnetically confined plasmas, and (3) controls and diagnostics on a fuseless railgun for solid hydrogen pellet injection.

  13. The response of motor neurones to intramuscular injection of botulinum toxin

    PubMed Central

    Watson, W. E.

    1969-01-01

    1. The dry mass and nucleic acid content of both nerve cell bodies and their nucleoli were measured by interference microscopy and ultra-violet absorption microspectrography respectively: succinoxidase and acetylcholine hydrolase activities were also determined. Autoradiography was used to follow synthesis of deoxyribonucleic acid (DNA) by glial cells, and to follow nucleic acid and protein metabolism in muscle fibres. 2. After injection of botulinum toxin the synthesis of ribosomal RNA by the neurone followed closely the pattern found after axotomy. 3. After injection of toxin neuronal dry mass increased before the rate of ribosomal RNA synthesis was raised. This early increase, which was not due to increased protein synthesis, probably represents a `damming back' of proteins within the nerve cell body. 4. After injection of toxin no local accumulation of microglial cells synthesizing DNA was found around the affected neurones: it is suggested that this reflects the intact system for intra-axonal transport under these conditions. 5. The affected muscles show increased nucleic acid and protein synthesis. 6. It is suggested that the results obtained indicate that membrane expansion or synthesis which occurs both in muscle and in neurone under these circumstances is the factor responsible for inducing directly or indirectly the changes found in nucleic acid metabolism after injection of botulinum toxin and after axotomy. ImagesFig. 1Fig. 2 PMID:4892690

  14. Injectable thermo-responsive hydrogel composed of xanthan gum and methylcellulose double networks with shear-thinning property.

    PubMed

    Liu, Zhijia; Yao, Ping

    2015-11-01

    Injectable hydrogel precursor solution was prepared by physical blend of xanthan gum (XG) and methylcellulose (MC) in aqueous solution. Due to the formation of XG network composed of XG double helical strand structure, XG/MC blend was a high viscous solution with good shear-thinning property at room temperature. When the temperature was changed from 23 to 37 °C, thermo-responsive MC network formed, which caused XG/MC blend solution to gelate. The gelation time and storage modulus of the blend can be tuned by XG and/or MC concentrations. Both in vitro and in vivo investigations revealed that the blend solution immediately recovered its high viscosity and rapidly formed hydrogel at body temperature after injection using a syringe. In vivo biocompatibility and biodegradability of the hydrogel were validated by implantation of the hydrogel in rats. In vitro investigation demonstrated that XG/MC blend is a promising injectable hydrogel material for long-term drug delivery. PMID:26256374

  15. Immune response of Pseudosciaena crocea to the injection of Vibrio alginolyticus

    NASA Astrophysics Data System (ADS)

    Yan, Qingpi; Zhang, Junjie; Zou, Wenzheng; Chen, Qiang; Zhuang, Zhixia; Wang, Xiaoru

    2009-02-01

    For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension of Vibrio alginolyticus in density of 2×107 CFU/ml, while each individual in the control group was injected i.p. with 0.2 ml sterile saline solution (0.85%). It was observed that the artificial injection of V. alginolyticus significantly increased the number of erythrocytes, leucocytes, lymphocytes in peripheral blood as well as peripheral serum antibacterial activity and antibody titer of large yellow croaker, and significantly reduced the number of peripheral blood granulocytes as compared with those in the control group. No significant difference in acid phosphytase and superoxide dismutase activity of serum was detected between the two groups. It is suggested that non-specific immune factors including leucocytes and anti-bacteria substance in peripheral blood played important role at the initial stage of infection, and specific immune factors such as antibody then played important role in response to anti-infection at the latter stage.

  16. Injection well with high-pressure, high-temperature in situ down-hole steam formation

    SciTech Connect

    Marr, A.W.

    1981-12-01

    A portion of an injection well adjacent an oil-bearing earth formation is sealed off by spaced-apart high-pressure-resistant plugs, and water is charged into the bore-hole space between the plugs at a sufficient rate to effect sustained water pressure in the range of from 400 to 25,000 psi. Under such pressure sufficient current is passed between two electrodes in the water to convert from 10 to 33 barrels of water per hour into steam.

  17. Radioguided occult lesion localization: better delineation of the injection site with a high-resolution collimator

    NASA Astrophysics Data System (ADS)

    Geissler, B.; De Freitas, D.; Cachin, F.; Mestas, D.; Lebouedec, G.; Maublant, J.

    2004-07-01

    Aim: Radioguided Occult Lesion Localization (ROLL) is a method for guiding the excision of occult breast lesions. A radiotracer is injected preoperatively in the tumor. The surgeon can locate the lesion with a gamma probe. It has been recommended that the tissue is resected where the activity falls rapidly. But this cut-off level can fluctuate depending on the user. The aim of this study was to compare the accuracy of two different types of collimation. Materials and methods: To simulate the detection of a radioactive "lesion", 0.2 ml of a solution of 99mTc labeled colloids (4 MBq) were deposited at 3 cm depth in a chunk of cow muscle. Detection was performed with a gamma probe (GammaSup, Clerad, F) equipped either with a regular or with an additional high-resolution collimator. The response curve was drawn moving laterally the probe on the chunk of cow by 5 mm steps. Edges of resection were determined with different cut-off levels (from 5 to 50% of maximum counts by 5% steps). Results: Without additional collimator, the mean distance between injection point and resection edge was 18 mm, standard deviation 7.8 mm with a range between 11 and 18 mm. With additional collimator, the mean distance decreased to 10 mm (-44%), standard deviation 4.2 mm (-46%) with a range between 6 and 10 mm. Conclusion: The results demonstrate that the additional collimator provides more precise and reproductive delineation of the injection site. It should be optimal for the ROLL technique.

  18. Dynamic response of micropipettes during piezo-assisted intracytoplasmic sperm injection

    NASA Astrophysics Data System (ADS)

    Karzar-Jeddi, Mehdi; Olgac, Nejat; Fan, Tai-Hsi

    2011-10-01

    In the intracytoplasmic sperm injection (ICSI) process, a piezoelectric actuator is commonly used to assist the piercing of cell membrane. The longitudinal pulses that are performed by the piezo actuator, however, cause undesired lateral vibrations at the drawn tip of the injection micropipette. This mechanism is not well understood, despite its critical role in piezo-assisted cellular microinjection. We provide an analytical model to characterize the micropipette tip vibrations under assumed base excitation arising from the piezoelectric pulses. The resulting dynamic response is determined by using the Duhamel integral method. This study quantifies the effect of fluid damping, embedded mercury, and the apparent cell membrane elasticity. We found that, in practice, a small mercury droplet filled in pipette essentially creates higher shear forces at the membrane-pipette interface. The increased shear due to underdamped eigenmodes is conceived to assist the piercing of the cell membrane.

  19. Preparation of an Awake Mouse for Recording Neural Responses and Injecting Tracers

    PubMed Central

    Muniak, Michael A.; Mayko, Zachary M.; Ryugo, David K.; Portfors, Christine V.

    2012-01-01

    It is well known that anesthesia alters neural response properties in various regions of the brain.13. In the auditory system, fundamental response properties of brainstem neurons including threshold, frequency specificity, and inhibitory sidebands are altered in significant ways under anesthesia1-2. These observations prompted physiologists to seek ways to record from single neurons without the contaminating effects of anesthesia. One result was a decerebrate preparation, where the brainstem was completely transected at the level of the midbrain4. The drawbacks of this preparation are a formidable surgery, the elimination of descending projections from the forebrain, and an inability to use sensory stimulation to examine structures above the midbrain. A different strategy has been to implant electrode arrays chronically to record from single neurons and multiunit clusters while the animal is awake and/or behaving5,6. These techniques however are not compatible with injecting tracer dyes after first electrophysiologically characterizing a brain structure. To avoid altering neural response properties with anesthetics while recording electrophysiological response properties from single neurons, we have adapted a head restraint technique long used in bats7-9 to mouse10-12. Using this method, we are able to conduct electrophysiological recordings over several days in the unanesthetized mouse. At the end of the recording sessions, we can then inject a dye to reconstruct electrode positions and recording sites or inject a tracer so that pathways to and from the recording loci can be determined. This method allows for well isolated single neuron recordings over multiple days without the use anesthetics. PMID:22781848

  20. HIV prevention among injecting drug users: responses in developing and transitional countries.

    PubMed Central

    Ball, A L; Rana, S; Dehne, K L

    1998-01-01

    OBJECTIVE: Human immunodeficiency virus (HIV) infection associated with injecting drug use has been reported in at least 98 countries and territories worldwide. There is evidence that new epidemics are emerging in different regions, including Eastern Europe, Latin American, and the eastern Mediterranean. The authors provide a global overview of the situation of HIV infection associated with injecting drug use and responses that have been implemented in various developing and transitional countries. METHODS: Although there has been extensive documentation of the extent and nature of of HIV infection associated with injecting drug use in many developed countries and the various interventions implemented in those countries, there is very limited information on the situation in developing and transitional countries. This chapter brings together information from a broad range of sources, including published literature; "gray" or "fugitive" literature; data collected by the World Health Organization (WHO), the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the United Nations International Drug Control Programme (UNDCP); personal communications; and direct observation by the authors. The authors have traveled extensively to a wide range of developing and transitional countries and have accessed information not readily available to the international research community. RESULTS: A wide range of HIV prevention strategies targeting injecting drug users (IDUs) has been implemented in developing countries and countries in transition. Interventions include opioid substitution pharmacotherapy, needle syringe exchange and distribution, condom and bleach distribution, outreach to IDUs, peer education programs, and social network interventions. In some communities, completely new models of intervention and service delivery have developed in response to specific local needs and limitations. CONCLUSIONS: Although empirical data may currently be lacking to demonstrate the

  1. Elastic stress transfer as a diffusive process due to aseismic fault slip in response to fluid injection

    NASA Astrophysics Data System (ADS)

    Viesca, R. C.

    2015-12-01

    Subsurface fluid injection is often followed by observations of an enlarging cloud of microseismicity. The cloud's diffusive growth is thought to be a direct response to the diffusion of elevated pore fluid pressure reaching pre-stressed faults, triggering small instabilities; the observed high rates of this growth are interpreted to reflect a relatively high permeability of a fractured subsurface [e.g., Shapiro, GJI 1997]. We investigate an alternative mechanism for growing a microseismic cloud: the elastic transfer of stress due to slow, aseismic slip on a subset of the pre-existing faults in this damaged subsurface. We show that the growth of the slipping region of the fault may be self-similar in a diffusive manner. While this slip is driven by fluid injection, we show that, for critically stressed faults, the apparent diffusion of this slow slip may quickly exceed the poroelastically driven diffusion of the elevated pore fluid pressure. Under these conditions, microseismicity can be first triggered by the off-fault stress perturbation due to the expanding region of slip on principal faults. This provides an alternative interpretation of diffusive growth rates in terms of the subsurface stress state rather than an enhanced hydraulic diffusivity. That such aseismic slip may occur, outpace fluid diffusion, and in turn trigger microseismic events, is also suggested by on- and near-fault observations in past and recently reported fluid injection experiments [e.g., Cornet et al., PAGEOPH 1997; Guglielmi et al., Science 2015]. The model of injection-induced slip assumes elastic off-fault behavior and a fault strength determined by the product of a constant friction coefficient and the local effective normal stress. The sliding region is enlarged by the pore pressure increase resolved on the fault plane. Remarkably, the rate of self-similar expansion may be determined by a single parameter reflecting both the initial stress state and the magnitude of the pore pressure

  2. High rates of midazolam injection among drug users in Bangkok, Thailand

    PubMed Central

    2010-01-01

    Background Reports from Thailand suggest that a growing number of people who inject drugs (IDU) are now injecting midazolam, a legal benzodiazepine with potent amnestic and ventilatory depressant effects. We therefore sought to examine midazolam injection among a community-recruited sample of Thai IDU. Methods We examined the prevalence and correlates of midazolam injection among 252 IDU participating in the Mitsampan Community Research Project, Bangkok, using multivariate logistic regression. We also examined the use of midazolam in combination with other drugs. Results 252 IDU participated in this study, including 66 (26.2%) women. In total, 170 (67.5%) participants reported ever having injected midazolam, and 144 (57.1%) reported daily midazolam injection in the past six months. In multivariate analyses, a history of midazolam injection was independently associated with using drugs in combination (adjusted odds ratio [AOR] = 5.86; 95% confidence interval [CI]: 2.96-11.60), younger age (AOR = 0.43; 95%CI: 0.22-0.83), having a history of methadone treatment (AOR = 3.12, 95%CI: 1.55-6.90), and binge drug use (AOR = 2.25, 95%CI: 1.09-4.63). The drugs most commonly used in combination with midazolam were heroin (72.3%) and yaba (methamphetamine) (30.5%). Conclusion We observed a high rate of midazolam injection among Thai IDU. Midazolam injection was strongly associated with polysubstance use and binge drug use, and was most commonly used in combination with both opiates and methamphetamines. Our findings suggest that midazolam injection has become increasingly common within Thailand. Evidence-based approaches for reducing harms associated with midazolam injection are needed. PMID:20338062

  3. A qualitative view of cryogenic fluid injection into high speed flows

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Schlumberger, J.; Proctor, M.

    1991-01-01

    The injection of supercritical pressure, subcritical temperature fluids, into a 2-D, ambient, static temperature and static pressure supersonic tunnel and free jet supersonic nitrogen flow field was observed. Observed patterns with fluid air were the same as those observed for fluid nitrogen injected into the tunnel at 90 deg to the supersonic flow. The nominal injection pressure was of 6.9 MPa and tunnel Mach number was 2.7. When injected directly into and opposing the tunnel exhaust flow, the observed patterns with fluid air were similar to those observed for fluid nitrogen but appeared more diffusive. Cryogenic injection creates a high density region within the bow shock wake but the standoff distance remains unchanged from the gaseous value. However, as the temperature reaches a critical value, the shock faded and advanced into the supersonic stream. For both fluids, nitrogen and air, the phenomena was completely reversible.

  4. A CFD Model for High Pressure Liquid Poison Injection for CANDU-6 Shutdown System No. 2

    SciTech Connect

    Bo Wook Rhee; Chang Jun Jeong; Hye Jeong Yun; Dong Soon Jang

    2002-07-01

    In CANDU reactor one of the two reactor shutdown systems is the liquid poison injection system which injects the highly pressurized liquid neutron poison into the moderator tank via small holes on the nozzle pipes. To ensure the safe shutdown of a reactor it is necessary for the poison curtains generated by jets provide quick, and enough negative reactivity to the reactor during the early stage of the accident. In order to produce the neutron cross section necessary to perform this work, the poison concentration distribution during the transient is necessary. In this study, a set of models for analyzing the transient poison concentration induced by this high pressure poison injection jet activated upon the reactor trip in a CANDU-6 reactor moderator tank has been developed and used to generate the poison concentration distribution of the poison curtains induced by the high pressure jets injected into the vacant region between the pressure tube banks. The poison injection rate through the jet holes drilled on the nozzle pipes is obtained by a 1-D transient hydrodynamic code called, ALITRIG, and this injection rate is used to provide the inlet boundary condition to a 3-D CFD model of the moderator tank based on CFX4.3, a CFD code, to simulate the formation of the poison jet curtain inside the moderator tank. For validation, an attempt was made to validate this model against a poison injection experiment performed at BARC. As conclusion this set of models is judged to be appropriate. (authors)

  5. Possible role of afferent autonomic signals in abdominal organs in anorexic and cardiovascular responses to nicotine injection in rats.

    PubMed

    Yagi, Shintaro; Tanida, Mamoru; Satomi, Jun

    2015-05-27

    Smoking generally causes an increase in nicotine levels in the blood, affecting the brain components, such as the hypothalamus (feeding-related area) or the brain stem (cardiovascular control area). In terms of nicotine transmission to the brain, a new insight that the afferent vagal nerve in the liver is important for sensing increased nicotine levels in the blood and informing the brain was reported in an experiment with rats. However, it has not been clarified whether the afferent autonomic nerve system is implicated in feeding and cardiovascular responses to nicotine. Here, we examined the possible role of afferent autonomic nerve transmission in rats in regulating feeding behavior and cardiovascular functions by nicotine. An intravenous injection of nicotine dose dependently increased the blood pressure (BP) in urethane-anesthetized rats; high nicotine doses also led to an increase in BP in conscious rats. Further, an intravenous injection of nicotine for 3 days reduced food intake and body weight gain in rats. The weight-reducing action of intravenous nicotine was abolished by blocking the afferent sympathetic signals in the abdominal organs, but not the vagal nerve signals. Moreover, the hypertensive action of nicotine was not abolished either by afferent sympathectomy or by vagotomy. Thus, these data suggest that nicotine injected into the vein acts on the afferent sympathetic nerve in the abdominal organs and transmits signals to the brain for reducing body weight, but not for suppressing appetite or increasing BP. PMID:25875474

  6. A regional evaluation of injections of high levels of vitamin A on reproductive performance of sows.

    PubMed

    Lindemann, M D; Brendemuhl, J H; Chiba, L I; Darroch, C S; Dove, C R; Estienne, M J; Harper, A F

    2008-02-01

    A regional study involving 443 litters from 182 sows was conducted at 5 cooperating experiment stations to determine the effects of an i.m. injection of vitamin A at weaning and breeding on subsequent litter size of sows. Sows were assigned to 1 of 3 treatments given at weaning and again at breeding: 1) a placebo i.m. injection (2 mL of corn oil), 2) i.m. injection with 250,000 IU of vitamin A (1 mL of vitamin A palmitate in oil), and 3) i.m. injection with 500,000 IU of vitamin A (2 mL of vitamin A palmitate in oil). Corn-soybean meal diets in gestation were formulated to contain 13% CP and 0.60% total Lys. Lactation diets were formulated to contain 17% CP and 0.90% Lys. A common vitamin-mineral premix that supplied 11,000 IU of vitamin A/kg of diet (as-fed) was used by all stations. As expected, station effects were noted for many response measures. Analysis of the data also revealed both treatment x station and treatment x parity interactions for litter size responses. The treatment x parity interactions were stronger than the treatment x station effects, and when the litter size response was separated into early parity sows (parity 1 and 2) and late-parity sows (parity 3 to 6), the treatment x station interactions were no longer present in either subgroup. For sows of parity 1 and 2, litter sizes were increased linearly (P

  7. Eicosanoids mediate Galleria mellonella immune response to hemocoel injection of entomopathogenic nematode cuticles.

    PubMed

    Yi, Yunhong; Wu, Gongqing; Lv, Junliang; Li, Mei

    2016-02-01

    Entomopathogenic nematodes are symbiotically associated with bacteria and widely used in biological control of insect pests. The interference of symbiotic bacteria with insect host immune responses is fairly well documented. However, knowledge of mechanisms regulating parasite–host interactions still remains fragmentary. In this study, we used nematode (Steinernema carpocapsae and Heterorhabditis bacteriophora) cuticles and Galleria mellonella larvae as parasite–host model, focused on the changes of innate immune parameters of the host in the early phase of nematode cuticle infection and investigated the role of eicosanoid biosynthesis pathway in the process. The results showed that injection of either S. carpocapsae or H. bacteriophora cuticles into the larval hemocoel both resulted in significant decreases in the key innate immune parameters (e.g., hemocyte density, microaggregation, phagocytosis and encapsulation abilities of hemocyte, and phenoloxidase and antibacterial activities of the cell-free hemolymph). Our study indicated that the parasite cuticles could actively suppress the innate immune response of the G. mellonella host. We also found that treating G. mellonella larvae with dexamethasone and indomethacin induced similar depression in the key innate immune parameters to the nematode cuticles. However, these effects were reversed when dexamethasone, indomethacin, or nematode cuticles were injected together with arachidonic acid. Additionally, we found that palmitic acid did not reverse the influence of the dexamethasone, indomethacin, or nematode cuticles on the innate immune responses. Therefore, we inferred from our results that both S. carpocapsae and H. bacteriophora cuticles inhibited eicosanoid biosynthesis to induce host immunodepression. PMID:26472713

  8. Substance Abuse Treatment, HIV/AIDS, and the Continuum of Response for People Who Inject Drugs

    PubMed Central

    Kresina, Thomas F.; Lubran, Robert; Clark, H. Westley; Cheever, Laura W.

    2012-01-01

    The continuum of response (CoR) to HIV/AIDS is a framework for implementation of HIV prevention, care, and treatment programs based on a national strategic plan for HIV/AIDS services. The CoR for people who inject drugs (PWID) is an important extension of the developed CoR to HIV/AIDS. The CoR-PWID employs stakeholders who together plan, develop, pilot, and provide a full range of services that address the various prevention, care/support, and treatment needs of people, families, and communities infected or affected by HIV/AIDS and injection drug use. The CoR-PWID comprises a broad range of services that include but are not limited to the World Health Organization priority interventions for HIV/AIDS prevention, treatment, and care in the health sector and the package of essential interventions for the prevention, treatment, and care of HIV for people who inject drugs. Implementation of these well-defined, essential prevention, care/support, and treatment services, in addition to locally defined needed services, in a coordinated fashion is important to clients, their families, and communities. The CoR-PWID is, therefore, a necessary framework essential for service development for countries that address HIV/AIDS in populations of PWID. PMID:23243517

  9. High-performance liquid chromatographic-amperometric determination of naloxone hydrochloride injection.

    PubMed

    Wilson, T D

    1984-08-17

    Naloxone hydrochloride has been measured in the injectable dosage form at 0.4 and 0.02 mg/ml using high-performance liquid chromatography with amperometric detection. This method was contrasted with an ultraviolet detection method at 229 nm and found to provide comparable recovery and linearity results. At the electrochemical detection limit of 0.1 ng injected a signal-to-noise ratio of 10.4 was found. PMID:6480748

  10. Cardiovascular responses to static exercise in conscious cats: effects of intracerebroventricular injection of clonidine.

    PubMed

    Ally, A; Hand, G A; Mitchell, J H

    1996-03-01

    1. Static exercise elicits increases in arterial blood pressure and heart rate (HR) in humans and conscious animals. In this study, the effects of intracerebroventricular (I.C.V.) administration of clonidine, an alpha 2-adrenergic agonist, on these cardiovascular responses were investigated using conscious cats. Four cats were operantly trained to extend a forelimb and press a bar (200-650 g) for 15-60 s. A stainless-steel cannula was inserted into the right lateral ventricle for I.C.V. injection of drugs, and a common carotid artery was catheterized to measure mean arterial pressure (MAP) and HR. The number of exercise trials and changes in MAP, HR and force were pooled for 30 min periods. After the cats exercised for 30 min, either artificial cerebrospinal fluid (CSF) or clonidine (2 or 5 micrograms) were administered intracerebroventricularly. 2. Before clonidine injection, fifty-two exercise trials increased MAP and HR by 15 +/- 3 mmHg and 41 +/- 5 beats min-1, respectively. Administration of clonidine (2 micrograms) did not alter the resting MAP and HR, but attenuated the increases in MAP and HR in response to exercise (0-30 min post-clonidine: n = 81; delta MAP, 6 +/- 3 mmHg; delta HR, 20 +/- 6 beats min-1; 30-60 min post-clonidine: n = 71; delta MAP, 4 +/- 4 mmHg; delta HR, 17 +/- 8 beats min-1). Administration of artificial CSF I.C.V. had no effect on the cardiovascular responses to static exercise. 3. An increased dose of clonidine (5 micrograms) decreased resting MAP and HR by 31 +/- 7 mmHg and 37 +/- 7 beats min-1, respectively, and markedly blunted the cardiovascular responses to exercise (pre-clonidine: n = 52; delta MAP, 17 +/- 3 mmHg; delta HR, 38 +/- 5 beats min-1; post-clonidine 0-30 min: n = 66; delta MAP, 4 +/- 2 mmHg; delta HR, 15 +/- 5 beats min-1; post-clonidine 30-60 min: n = 60; delta MAP, 4 +/- 2 mmHg; delta HR, 14 +/- 6 beats min-1). Pretreatment with the alpha 2-adrenergic antagonist, yohimbine (8 micrograms, I.C.V.), blocked the

  11. Vocal aging and adductor spasmodic dysphonia: Response to botulinum toxin injection

    PubMed Central

    Cannito, Michael P; Kahane, Joel C; Chorna, Lesya

    2008-01-01

    Aging of the larynx is characterized by involutional changes which alter its biomechanical and neural properties and create a biological environment that is different from younger counterparts. Illustrative anatomical examples are presented. This natural, non-disease process appears to set conditions which may influence the effectiveness of botulinum toxin injection and our expectations for its success. Adductor spasmodic dysphonia, a type of laryngeal dystonia, is typically treated using botulinum toxin injections of the vocal folds in order to suppress adductory muscle spasms which are disruptive to production of speech and voice. A few studies have suggested diminished response to treatment in older patients with adductor spasmodic dysphonia. This retrospective study provides a reanalysis of existing pre-to-post treatment data as function of age. Perceptual judgments of speech produced by 42 patients with ADSD were made by two panels of professional listeners with expertise in voice or fluency of speech. Results demonstrate a markedly reduced positive response to botulinum toxin treatment in the older patients. Perceptual findings are further elucidated by means of acoustic spectrography. Literature on vocal aging is reviewed to provide a specific set of biological mechanisms that best account for the observed interaction of botulinum toxin treatment with advancing age. PMID:18488884

  12. Construction of a Direct Water-Injected Two-Stroke Engine for Phased Direct Fuel Injection-High Pressure Charging Investigations

    NASA Technical Reports Server (NTRS)

    Somsel, James P.

    1998-01-01

    The development of a water injected Orbital Combustion Process (OCP) engine was conducted to assess the viability of using the powerplant for high altitude NASA aircraft and General Aviation (GA) applications. An OCP direct fuel injected, 1.2 liter, three cylinder, two-stroke engine has been enhanced to independently inject water directly into the combustion chamber. The engine currently demonstrates low brake specific fuel consumption capability and an excellent power to weight ratio. With direct water injection, significant improvements can be made to engine power, to knock limits/ignition advance timing, and to engine NO(x) emissions. The principal aim of the testing was to validate a cyclic model developed by the Systems Analysis Branch at NASA Ames Research Center. The work is a continuation of Ames' investigations into a Phased Direct Fuel Injection Engine with High Pressure Charging (PDFI-ITPC).

  13. Geomechanical Modeling of Fault Responses and the Potential for Notable Seismic Events during Underground CO2 Injection

    NASA Astrophysics Data System (ADS)

    Rutqvist, J.; Cappa, F.; Mazzoldi, A.; Rinaldi, A.

    2012-12-01

    The importance of geomechanics associated with large-scale geologic carbon storage (GCS) operations is now widely recognized. There are concerns related to the potential for triggering notable (felt) seismic events and how such events could impact the long-term integrity of a CO2 repository (as well as how it could impact the public perception of GCS). In this context, we review a number of modeling studies and field observations related to the potential for injection-induced fault reactivations and seismic events. We present recent model simulations of CO2 injection and fault reactivation, including both aseismic and seismic fault responses. The model simulations were conducted using a slip weakening fault model enabling sudden (seismic) fault rupture, and some of the numerical analyses were extended to fully dynamic modeling of seismic source, wave propagation, and ground motion. The model simulations illustrated what it will take to create a magnitude 3 or 4 earthquake that would not result in any significant damage at the groundsurface, but could raise concerns in the local community and could also affect the deep containment of the stored CO2. The analyses show that the local in situ stress field, fault orientation, fault strength, and injection induced overpressure are critical factors in determining the likelihood and magnitude of such an event. We like to clarify though that in our modeling we had to apply very high injection pressure to be able to intentionally induce any fault reactivation. Consequently, our model simulations represent extreme cases, which in a real GCS operation could be avoided by estimating maximum sustainable injection pressure and carefully controlling the injection pressure. In fact, no notable seismic event has been reported from any of the current CO2 storage projects, although some unfelt microseismic activities have been detected by geophones. On the other hand, potential future commercial GCS operations from large power plants

  14. Injectable, high-density collagen gels for annulus fibrosus repair: An in vitro rat tail model.

    PubMed

    Borde, Brandon; Grunert, Peter; Härtl, Roger; Bonassar, Lawrence J

    2015-08-01

    A herniated intervertebral disc often causes back pain when disc tissue is displaced through a damaged annulus fibrosus. Currently, the only methods available for annulus fibrosus repair involve mechanical closure of defect, which does little to address biological healing in the damaged tissue. Collagen hydrogels are injectable and have been used to repair annulus defects in vivo. In this study, high-density collagen hydrogels at 5, 10, and 15 mg/mL were used to repair defects made to intact rat caudal intervertebral discs in vitro. A group of gels at 15 mg/mL were also cross-linked with riboflavin at 0.03 mM, 0.07 mM, or 0.10 mM. These cross-linked, high-density collagen gels maintained their presence in the defect under loading and contributed positively to the mechanical response of damaged discs. Discs exhibited increases to 95% of undamaged effective equilibrium and instantaneous moduli as well as up to fourfold decreases in effective hydraulic permeability from the damaged discs. These data suggest that high-density collagen gels may be effective at restoring mechanical function of injured discs as well as potential vehicles for the delivery of biological agents such as cells or growth factors that may aid in the repair of the annulus fibrosus. PMID:25504661

  15. Evaluation of injection methods for fast, high peak capacity separations with low thermal mass gas chromatography.

    PubMed

    Fitz, Brian D; Mannion, Brandyn C; To, Khang; Hoac, Trinh; Synovec, Robert E

    2015-05-01

    Low thermal mass gas chromatography (LTM-GC) was evaluated for rapid, high peak capacity separations with three injection methods: liquid, headspace solid phase micro-extraction (HS-SPME), and direct vapor. An Agilent LTM equipped with a short microbore capillary column was operated at a column heating rate of 250 °C/min to produce a 60s separation. Two sets of experiments were conducted in parallel to characterize the instrumental platform. First, the three injection methods were performed in conjunction with in-house built high-speed cryo-focusing injection (HSCFI) to cryogenically trap and re-inject the analytes onto the LTM-GC column in a narrower band. Next, the three injection methods were performed natively with LTM-GC. Using HSCFI, the peak capacity of a separation of 50 nl of a 73 component liquid test mixture was 270, which was 23% higher than without HSCFI. Similar peak capacity gains were obtained when using the HSCFI with HS-SPME (25%), and even greater with vapor injection (56%). For the 100 μl vapor sample injected without HSCFI, the preconcentration factor, defined as the ratio of the maximum concentration of the detected analyte peak relative to the analyte concentration injected with the syringe, was determined to be 11 for the earliest eluting peak (most volatile analyte). In contrast, the preconcentration factor for the earliest eluting peak using HSCFI was 103. Therefore, LTM-GC is demonstrated to natively provide in situ analyte trapping, although not to as great an extent as with HSCFI. We also report the use of LTM-GC applied with time-of-flight mass spectrometry (TOFMS) detection for rapid, high peak capacity separations from SPME sampled banana peel headspace. PMID:25814332

  16. Injection coupling with high amplitude transverse modes: Experimentation and simulation

    NASA Astrophysics Data System (ADS)

    Mery, Yoann; Ducruix, Sébastien; Scouflaire, Philippe; Candel, Sébastien

    2009-06-01

    High frequency combustion instabilities have technical importance in the design of liquid rocket engines. These phenomena involve a strong coupling between transverse acoustic modes and combustion. They are currently being investigated by combining experimentation and numerical simulations. On the experimental level, the coupling is examined in a model scale system featuring a multiple injector combustor (MIC) comprising five coaxial injectors fed with liquid oxygen and gaseous methane. This system is equipped with a novel VHAM actuator (Very High Amplitude Modulator) which comprises two nozzles and a rotating toothed wheel blocking the nozzles in an alternate fashion. This device was designed to obtain the highest possible levels of transverse oscillation in the MIC. After a brief review of the VHAM, this article reports cold flow experiments using this modulator. Velocity maps obtained under resonant conditions using the VHAM are examined at different instants during a cycle of oscillation. Experimental data are compared with numerical pressure and velocity fields obtained from an acoustic solver. The good agreement observed in the nozzle vicinity indicates that numerical simulations can be used to analyze the complex flow field generated by the VHAM. To cite this article: Y. Mery et al., C. R. Mecanique 337 (2009).

  17. High performance tunnel injection quantum dot comb laser

    SciTech Connect

    Lee, C.-S.; Guo Wei; Basu, Debashish; Bhattacharya, Pallab

    2010-03-08

    A high-speed multiwavelength quantum dot comb laser, grown by molecular beam epitaxy, is demonstrated. The device is characterized with a 75.9 nm (full width at half maximum) and a 91.4 nm (DELTA{sub -15dB}) wide lasing spectrum. There are 105 and 185 simultaneously emitted longitudinal modes with a maximum channel intensity nonuniformity of less than 3 dB in the spectral range of 1231-1252 nm and 1274-1311 nm, respectively, for a laser with 1040 mum cavity length. The channel spacing can be tuned with cavity length and remains invariant in the temperature range of 300-323 K. The small signal modulation bandwidth is 7.5 GHz.

  18. MICROSCALE FLOW INJECTION AND MICROBORE HIGH-PERFORMANCE LIQUID CHROMATORGRAPHY COUPLED WITH INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY VIA A HIGH-EFFICIENCY NEBULIZER

    EPA Science Inventory

    A high-effeciency nebulizer has been used for coupling microscale flow injection and microbore high-performance liquid chromatography with inductively coupled plasma mass spectrometry (ICPMS). The microscale flow injection system was configured to minimize band broadening between...

  19. Botulinum toxin injection for hypercontractile or spastic esophageal motility disorders: may high-resolution manometry help to select cases?

    PubMed

    Marjoux, S; Brochard, C; Roman, S; Gincul, R; Pagenault, M; Ponchon, T; Ropert, A; Mion, F

    2015-01-01

    Endoscopic injections of botulinum toxin in the cardia or distal esophagus have been advocated to treat achalasia and spastic esophageal motility disorders. We conducted a retrospective study to evaluate whether manometric diagnosis using the Chicago classification in high-resolution manometry (HRM) would be predictive of the clinical response. Charts of patients with spastic and hypertensive motility disorders diagnosed with HRM and treated with botulinum toxin were retrospectively reviewed at two centers. HRM recordings were systematically reanalyzed, and a patient's phone survey was conducted. Forty-five patients treated between 2008 and 2013 were included. Most patients had achalasia type 3 (22 cases). Other diagnoses were jackhammer esophagus (8 cases), distal esophageal spasm (7 cases), esophagogastric junction outflow obstruction (5 cases), nutcracker esophagus (1 case), and 2 unclassified cases. Botulinum toxin injections were performed into the cardia only in 9 cases, into the wall of the distal esophagus in 19 cases, and in both locations (cardia and distal esophagus) in 17 cases. No complication occurred in 31 cases. Chest pain was noticed for less than 7 days in 13 cases. One death related to mediastinitis occurred 3 weeks after botulinum toxin injection. Efficacy was assessed in 42 patients: 71% were significantly improved 2 months after botulinum toxin, and 57% remained satisfied for more than 6 months. No clear difference was observed in terms of response according to manometric diagnosis; however, type 3 achalasia previously dilated and with normal integrated relaxation pressure (4s-integrated relaxation pressure < 15 mmHg) had the worst outcome: none of these patients responded to the endoscopic injection of botulinum toxin. Endoscopic injections of botulinum toxin may be effective in some patients with spastic or hypercontractile esophageal motility disorders. The manometric Chicago classification diagnosis does not seem to predict the results

  20. Biopersistence of synthetic mineral fibers as a predictor of chronic intraperitoneal injection tumor response in rats.

    PubMed

    Bernstein, D M; Riego Sintes, J M; Ersboell, B K; Kunert, J

    2001-10-01

    In December 1997 the European Commission (EC) adopted Directive 97/69/EC (O.J. L 343/19 of 13 December 1997), in which criteria were established for the classification and labeling of synthetic mineral fibers. This directive was derived based upon an extensive program evaluating current scientific knowledge on fiber pathogenicity and its relationship to the biopersistence of long fibers. Within this context, the biopersistence of fibers longer than 20 microm was found to be a good predictor of the lung burden and early pathological changes in chronic inhalation studies with fibers as well as of the tumor response in chronic intraperitoneal studies with fibers. The analysis that provided the scientific basis for the relationship of biopersistence to the chronic intraperitoneal (ip) results is presented in detail. Analysis of the relationship of biopersistence clearance half-times to ip tumor response shows a statistically significant relationship of ip tumor response to not only the number of fibers injected, but also the median length of the fibers injected and their solubility (clearance half-time). The results show that the biopersistence half-times as determined by intratracheal instillation (T(1/2) of WHO fibers or weighted T(1/2) of fibers with L > 20 microm) and as determined by inhalation (weighted T(1/2) of fibers with L > 20 microm) are equivalent predictors of the ip results. From these ip studies, fibers that can be exonerated from classification as carcinogens in Europe have a relative tumorigenic potency in the ip cavity of between 66 and 2500 times less than fibers that have been shown to produce a significant increase in tumors following chronic inhalation exposure. In addition, based upon the ip results, there is no statistical difference between the EC and the other fiber exoneration criteria, such as the German Gefahrstoffverordnung of 1999. PMID:11696864

  1. Effects of lidocaine injections into the lateral parabrachial nucleus on dipsogenic and pressor response to central angiotensin 2 in rats

    NASA Technical Reports Server (NTRS)

    Menani, Jose Vanderlei; Beltz, Terry G.

    1995-01-01

    This study investigated the effects of bilateral injections of the local anesthetic, lidocaine, into the lateral parabrachial nucleus (LPBN) on the dipsogenic and pressor responses induced by intracerebroventricular (i.c.v.) injection of angiotensin 2 (ANG 2). Centrally injected ANG 2 (50 ng/1 microliter) induced water intake ( IO.2 +/- 0.8 ml/h) and pressor responses (22 +/- 1 mmHg). Prior bilateral injection of 10% lidocaine (200 nl) into the LPBN increased the water intake (14.2 +/- 1.4 ml/h), but did not change the pressor response (17 +/- 1 mmHg) to i.c.v. ANG 2. Lidocaine alone injected into the LPBN also induced a pressor response (23 +/- 3 mmHg). These results showing that bilateral LPBN injection of lidocaine increase water intake induced bv i.c.v. ANG 2 are consistent with electrolytic and neurotoxic lesion studies and suggest that the LPBN is associated with inhibitory mechanisms controlling water intake induced by ANG 2. These results also provide evidence that it is feasible to reversibly anesthetize this brain area to facilitate fluid-related ingestive behavior.

  2. Mathematical modeling as a tool to assess microbial community responses to CO2 injection

    NASA Astrophysics Data System (ADS)

    Vilcaez, J.

    2014-12-01

    The issue of subsurface microbial community responses to the injection of CO2 has great importance not only from a risk assessment point of view but also from the perspective of CO2 recycling to CH4. In this sense, the objective of this study is to develop mathematical models to make a quantitative description of the responses of subsurface indigenous microbial communities to the injection of CO2. For this end, TOUGHREACTV1.2 reactive transport simulator with its module ECO2N is used as the modeling framework. The targeted microbial community is composed of fermentative bacteria (Organic matter → Acetate & H2), acetotrophic methanogens (Acetate → Methane & CO2), acetotrophic Sulfate Reducing Bacteria (SRB) (Acetate → H2S & CO2), hydrogenotrophic methanogens (H2 & CO2 → CH4), and hydrogenotrophic SRB (H2 → H2S). Due to the multiple hydrogeological, geochemical and microbiological factors intervening in both the response of subsurface microbial communities to the injection of CO2 and the chemical and physical fate of CO2 itself, at this stage simulations have been performed in batch mode. That means numerical simulations aimed to track changes in CO2 saturation levels, pH, and concentrations of mineral and aqueous phase species over time at selected initial conditions. Numerical simulation results indicate that the activity of microbes associated with methanogenic processes in geological storage sites of CO2 is governed by the level of CO2 saturation in the pore space as well as by the presence of pH buffering minerals such as calcite. With calcite in the mineral phase attenuating drops in pH below inhibitory levels, for instance it is shown that acetotrophic and hydrogenotrophic SRB outcompete acetotrophic and hydrogenotrophic methanogens for acetate and H2, respectively. During the initial stages of the reaction when the pH level is lowest, the higher tolerance of hydrogenotrophic methanogens to acidic pH levels is reflected by a preferential formation of

  3. Synchronously injected amplifiers, a novel approach to high-average-power FEL

    SciTech Connect

    Nguyen, D.C.; Fortgang, C.M.; Goldstein, J.C.; Kinross-Wright, J.M.; Sheffield, R.L.

    1996-11-01

    Two new FEL ideas based on synchronously injected amplifiers are described. Both of these rely on the synchronous injection of the optical signal into a high-gain, high-efficiency tapered wiggler. The first concept, called Regenerative Amplifier FEL (RAFEL), uses an optical feedback loop to provide a coherent signal at the wiggler entrance so that the optical power can reach saturation rapidly. The second idea requires the use of a uniform wiggler in the feedback loop to generate light that can be synchronously injected back into the first wiggler. The compact Advanced FEL is being modified to implement the RAFEL concept. We describe future operation of the Advanced FEL at high average current and discuss the possibility of generating 1 kW average power.

  4. Specific inflammatory response of Anemonia sulcata (Cnidaria) after bacterial injection causes tissue reaction and enzymatic activity alteration.

    PubMed

    Trapani, M R; Parisi, M G; Parrinello, D; Sanfratello, M A; Benenati, G; Palla, F; Cammarata, M

    2016-03-01

    The evolution of multicellular organisms was marked by adaptations to protect against pathogens. The mechanisms for discriminating the ''self'' from ''non-self" have evolved into a long history of cellular and molecular strategies, from damage repair to the co-evolution of host-pathogen interactions. We investigated the inflammatory response in Anemonia sulcata (Cnidaria: Anthozoa) following injection of substances that varied in type and dimension, and observed clear, strong and specific reactions, especially after injection of Escherichia coli and Vibrio alginolyticus. Moreover, we analyzed enzymatic activity of protease, phosphatase and esterase, showing how the injection of different bacterial strains alters the expression of these enzymes and suggesting a correlation between the appearance of the inflammatory reaction and the modification of enzymatic activities. Our study shows for the first time, a specific reaction and enzymatic responses following injection of bacteria in a cnidarian. PMID:26836977

  5. Effect of age and frequency of injections on immune response to hepatitis B vaccination in drug users.

    PubMed

    Tran, Thanh Q; Grimes, Carolyn Z; Lai, Dejian; Troisi, Catherine L; Hwang, Lu-Yu

    2012-01-01

    Despite the high immunogenicity of the hepatitis B vaccine, evidence suggests that immunological response in drug users is impaired compared to the general population. A sample of not-in-treatment adult drug users from two communities in Houston, TX, USA, susceptible to hepatitis B virus (HBV), was sampled via outreach workers and referral methodology. Participants were randomized to either the standard multi-dose hepatitis B vaccine schedule (0, 1, and 6 months) or to an accelerated (0, 1, and 2 months) schedule. The participants were followed for 1 year. Antibody levels were measured at 2, 6 and 12 months after enrollment in order to determine the immune responses. At 12 months, cumulative adequate protective response was achieved in 65% of the HBV susceptible subgroup using both the standard and accelerated schedules. The standard group had a higher mean antibody titer (184.6 mIU/mL vs 57.6 mIU/mL). But at 6 months, seroconversion at the adequate protective response was reached by a higher proportion of participants and the mean antibody titer was also higher in the accelerated schedule group (104.8 mIU/mL vs. 64.3 mIU/mL). Multivariate analyses indicated a 63% increased risk of non-response for participants 40 years or older (p=0.046). Injecting drugs more than once a day was also highly associated with the risk of non-response (p=0.016). Conclusions from this research will guide the development of future vaccination programs that anticipate other prevalent chronic conditions, susceptibilities, and risk-taking behaviors of hard-to-reach populations. PMID:22075088

  6. Uncertainty quantification for the impact of injection rate fluctuation on the geomechanical response of geological carbon sequestration

    SciTech Connect

    Bao, Jie; Chu, Yanjun; Xu, Zhijie; Tartakovsky, Alexandre M.; Fang, Yilin

    2014-01-01

    We present an analysis of the geomechanical effects of injection rate fluctuations for geological sequestration of carbon dioxide (CO2). Initially, we present analytical solutions for the effects of injection rate fluctuations on CO2 fluid pressure spatial distribution and temporal evolution for a typical injection scenario. Numerical calculations are performed using a finite element method to investigate the effects of injection rate fluctuations on geomechanical deformation, stresses, and potential failure of the aquifer and caprock layers. The numerical method was first validated by the fluid pressure distribution’s good agreement with the analytical solution. It was shown that for any Gaussian fluctuations of injection rate Q with given mean Q and variance ε_Q, the coefficients of variance for fluid pressure (ϵ_p=ε_p ), deformation (ϵ_u=ε_u ), and stresses (ϵ_σ=ε_σ ) increase linearly with the coefficient of variance for injection rate (ϵ_Q=ε_Q ). The proportional constants are identified, and the fluctuations have the most pronounced effect on the geomechanical stresses, and, therefore, on the potential failure of the aquifer and caprock layers. Instead of expensive computational simulation, this study provides an efficient tool to estimate the geomechanical response variance to injection rate fluctuation. A failure analysis was presented based on the numerical results, where probability of failure was estimated for fluctuating injection rates with different mean and variance during the entire injection period. It was found that with increasing injection rate fluctuation, the failure probability increases significantly. Therefore, the risk associated with injection rate fluctuations should be carefully evaluated.

  7. High HIV burden among people who inject drugs in 15 Indian cities

    PubMed Central

    Lucas, Gregory M.; Solomon, Sunil S.; Srikrishnan, Aylur K.; Agrawal, Alok; Iqbal, Syed; Laeyendecker, Oliver; McFall, Allison M.; Kumar, Muniratnam S.; Ogburn, Elizabeth; Celentano, David D.; Solomon, Suniti; Mehta, Shruti H.

    2015-01-01

    Background Injecting drug use has historically been the principal driver of the HIV epidemic in the Northeast states of India. However, recent data indicate growing numbers of people who inject drugs (PWID) in North and Central Indian cities. Methods We conducted face-to-face surveys among PWID in 7 Northeast and 8 North/Central Indian cities using respondent-driven sampling. We used a rapid HIV testing protocol to identify seropositive individuals and multi-assay algorithm to identify those with recent infection. We used multi-level regression models that incorporated sampling weights and had random intercepts for site to assess risk factors for prevalent and incident (recent) HIV infection. Results We surveyed 14,481 PWID from 15 Indian cities between January and December 2013. Participants reported high rates of needle/syringe sharing. The median (site range) estimated HIV prevalence and incidence were 18.1% (5.9, 44.9) and 2.9 per 100 person-years (0, 12.4), respectively. HIV prevalence was higher in Northeast sites while HIV incidence was higher in North/Central sites. The odds of prevalent HIV were over 3-fold higher in women than men. Other factors associated with HIV prevalence or incidence included duration since first injection, injection of pharmaceutical drugs, and needle/syringe sharing. Conclusions The burden of HIV infection is high among PWID in India, and may be increasing in cities where injecting drug use is emerging. Women who inject drugs were at substantially higher risk for HIV than men, a situation that may be mediated by dual injection-related and sexual risks. PMID:25715105

  8. A higher aspect ratio enhanced bioaccumulation and altered immune responses due to intravenously-injected aluminum oxide nanoparticles.

    PubMed

    Park, Eun-Jung; Kim, Soo Nam; Kang, Min-Sung; Lee, Byoung-Seok; Yoon, Cheolho; Jeong, Uiseok; Kim, Younghun; Lee, Gwang-Hee; Kim, Dong-Wan; Kim, Jong Sung

    2016-07-01

    Aluminum oxide nanoparticles (AlO NP) have been widely utilized in a variety of areas, including in the optical, biomedical and electronic fields and in the overall development of nanotechnologies. However, their toxicological profiles are still not fully developed. This study compared the distribution and immunotoxicity of two rod-types of AlO NP. As reported previously, the two types of AlO NP had different aspect ratios (long-type: 6.2 ± 0.6, short-type: 2.1 ± 0.4), but the size and surface charge were very similar. On Day 14 after a single intravenous (IV) injection (1.25 or 5 mg/kg), both AlO NP accumulated primarily in the liver and spleen and altered the levels of redox response-related elements. The accumulated level was higher in mice exposed to the long-type AlO NP compared to the short-type. Additionally, it was noted that the levels of IL-1β, IL-8 and MCP-1 were enhanced in the blood of mice exposed to both types of AlO NP and the percentages of neutrophils and monocytes among all white blood cells were increased only in mice injected with the long-type AlO NP (5 mg/kg). In addition, as compared to the control, co-expression of CD80 and CD86 (necessary for antigen presentation) on splenocytes together with a decreased expression of chemotaxis-related marker (CD195) was attenuated by exposure to the AlO NP, especially the long-type. Taken together, the data suggest that accumulation following a single IV injection with rod-types of AlO NP is strengthened by a high aspect ratio and, subsequently, this accumulation has the potential to influence immune functions in an exposed host. PMID:27042761

  9. Stability of High Power Beam Injection in Negative-Ion-Based LHD-NBI

    SciTech Connect

    Tsumori, K.; Kaneko, O.; Takeiri, Y.; Osakabe, M.; Ikeda, K.; Nagaoka, K.; Nakano, H.; Shibuya, M.; Asano, E.; Kondo, T.; Sato, M.; Komada, S.; Sekiguchi, H.

    2011-09-26

    We describe the characteristic of stable beam injection in a neutral beam injector (NBI) for Large Helical Device (LHD) in high injection power of more than 6 MW. In the NBI, it takes a week after starting Cs seeding to finish the pre-injection conditioning. The injection starts with the beam power {approx}6.2 MW, and the maximum power reaches {approx}7 MW. The Cs-seeding rate affects the beam stability in such high power injections. By optimizing the rate to 0.65 mg/shot, the success ratio, which is defined as a ratio of actual pulse duration to setting one, increases to 85-90% in the power and energy range of more than 6.2 MW and 185 keV, respectively. The weights of Cs adsorbed on several surfaces in the ion sources of the NBI are measured by means of Inductively-Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), and averaged surface densities are calculated by dividing with the several surface areas. The seeded Cs of 99.5% is condensed in the plasma generator, and very tiny amount of Cs reaches the surfaces of the accelerator grids. This very low amount of Cs on the grids is interpreted that most of the Cs atom evaporated from the inner walls is ionized during the arc discharges, and repelled to the source plasmas by the electrostatic field for H- extraction.

  10. Injection molding simulation with variothermal mold temperature control of highly filled polyphenylene sulfide

    NASA Astrophysics Data System (ADS)

    Birkholz, A.; Tschiersky, M.; Wortberg, J.

    2015-05-01

    For the installation of a fuel cell stack to convert chemical energy into electricity it is common to apply bipolar plates to separate and distribute reaction gases and cooling agents. For reducing manufacturing costs of bipolar plates a fully automated injection molding process is examined. The high performance thermoplastic matrix material, polyphenylene sulfide (PPS), defies against the chemical setting and the operation temperature up to 200 °C. To adjust also high electrical and thermal conductivity, PPS is highly filled with various carbon fillers up to an amount of 65 percentage by volume. In the first step two different structural plates (one-sided) with three different gate heights and molds are designed according to the characteristics of a bipolar plate. To cope with the approach that this plate should be producible on standard injection molding machines with variothermal mold temperature control, injection molding simulation is used. Additionally, the simulation should allow to formulate a quality prediction model, which is transferrable to bipolar plates. Obviously, the basis for a precise simulation output is an accurate description of the material properties and behavior of the highly filled compound. This, the design of the structural plate and mold and the optimization via simulation is presented, as well. The influence of the injection molding process parameters, e.g. injection time, cycle times, packing pressure, mold temperature, and melt temperature on the form filling have been simulated to determine optimal process conditions. With the aid of the simulation and the variothermal mold temperature control it was possible to reduce the required melt temperature below the decomposition temperature of PPS. Thereby, hazardous decomposition products as hydrogen sulfide are obviated. Thus, the health of the processor, the longevity of the injection molding machine as well as the material and product properties can be protected.

  11. Highly efficient and lowly toxic docetaxel nanoemulsions for intravenous injection to animals.

    PubMed

    Li, Xin; Du, Lina; Wang, Chenyun; Liu, Yan; Mei, Xingguo; Jin, Yiguang

    2011-07-01

    Hypersensitivity many occur with commercial docetaxel injections containing Tween 80 and ethanol. An alternative formulation of docetaxel, an oil-in-water nanoemulsion was prepared using the high-pressure homogenization method. It was composed of medium-chain triglyceride, oleic acid, egg lecithin, and poloxamer. These ingredients are known as safe agents for intravenous (i.v.) injection. The nanoemulsion had a small size of 169 nm, and a high surface charge with the zeta potential of -33.9 mV. It maintained well stable even under high centrifugation. Acute toxicity of i.v. injection, erythrocyte hemolysis experiment, and rabbit ear vein irritation test showed no toxicity for the docetaxel nanoemulsion. The docetaxel nanoemulsion led to a larger apparent distribution volume and area under curve than the docetaxel injection after i.v. administration to rats. The histopathological test of tumor further demonstrated the highly anticancer efficiency of the docetaxel nanoemulsion. Thus, the nanoemulsion is a promising delivery system for docetaxel with highly anticancer efficiency and low toxicity. PMID:21812321

  12. Response of Slub Characteristics on Tensile Properties of Injected Slub Yarn

    NASA Astrophysics Data System (ADS)

    Ray, N. C.; Mukhopadhyay, A.; Midha, V. K.

    2016-04-01

    Injected slub yarn is one of the most promising among different types of slub yarns. Present study embodies the effect of some important parameters like base yarn twist level, number of base yarn, twist direction and injected fibre components on injected slub yarn performance in terms of tensile strength and breaking elongation. In case of single base slub yarn, final yarn tenacity and elongation increases with the reduction of base yarn twist level keeping final yarn twist multiplier constant. However, the effect of base yarn twist level is marginal in case of injected slub yarn made with double base yarn. Yarn tenacity and elongation significantly higher in case of double base injected yarns as compared to single base injected yarn. The aforementioned tensile parameters of single base injected slub yarns reduce with the reduction of yarn linear density. However, in case of double base injected slub yarns, highest tenacity and elongation value are achieved for 2/80s yarn having finest yarn liner density among 2/40s, 2/60s and 2/80s yarns. In case of single base injected slub yarn, tensile strength is slightly higher and elongation values are significantly higher when injection component fibres changed from 100 % cotton to 50/50 polyester/cotton blended fibres which is just opposite to that of double base injected slub yarn. Results also showed that the twist direction in the base and final yarn influence the strength and elongation of injected slub yarns.

  13. Observation of a Distinct Transition in Transport Response to Injection Stress in the Floridan Aquifer System, Southeastern Florida, U.S.A

    NASA Astrophysics Data System (ADS)

    King, J. N.; Cunningham, K. J.; Foster, A. L.

    2011-12-01

    The Miami-Dade Water and Sewer Department (MDWASD) injects effluent approximately one km below land surface into the Boulder Zone (BZ) at the North District Wastewater Treatment Plant (NDWWTP). The BZ is highly conductive and composed of fractured dolomite. MDWASD monitors upward effluent migration 450 m below land surface in the Avon Park Permeable Zone (APPZ). The BZ and APPZ---units within the Floridan aquifer system---are separated by a series of inter-bedded aquifers and leaky confining units with hydraulic conductivities that are orders of magnitude smaller than the BZ. MDWASD injected effluent at the NDWWTP during two distinct periods: (1) July 1997 to September 1999, and (2) August 2004 to January 2011. No effluent was injected between October 1999 and July 2004. A few months after the July 1997 injection, MDWASD observed effluent constituents in the APPZ (Figure 1). Some confinement bypass feature permits effluent constituents to be transported from the BZ to the APPZ. Bypass features may include poorly-cased wells, or natural conduits such as fractures, faults, or karst collapse systems. It is possible to describe confinement bypass features with conductance KA/L, where K is hydraulic conductivity, A is cross-sectional area, and L is length. MDWASD observed a distinct transition in the transport response to injection stress of total dissolved solids (TDS) concentration in the APPZ. The conductance required to describe early system response (1997-1999) is one order-of-magnitude larger than the conductance required to describe late system response (2004-2011). Hypotheses to explain transient conductance include clogging of bypass features by some geochemical or biological process that results from the mixing of effluent with groundwater; dissolution or precipitation; or changes in bypass-feature geometry forced by cyclical changes in aquifer-fluid pressure associated with injection. Hypotheses may be tested with geochemical analyses, tracer tests, hydraulic

  14. Flow-induced birefringence: the hidden PSF killer in high performance injection-molded plastic optics

    NASA Astrophysics Data System (ADS)

    Chidley, Matthew D.; Tkaczyk, Tomasz; Kester, Robert; Descour, Michael R.

    2006-02-01

    A 7-mm OD, NA = 1 water immersion injection-molded plastic endoscope objective has been fabricated for a laser scanning fiber confocal reflectance microscope (FCRM) system specifically designed for in vivo detection of cervical and oral pre-cancers. Injection-molded optics was selected for the ability to incorporate aspheric surfaces into the optical design and its high volume capabilities. Our goal is high performance disposable endoscope probes. This objective has been built and tested as a stand-alone optical system, a Strehl ratio greater than 0.6 has been obtained. One of the limiting factors of optical performance is believed to be flow-induced birefringence. We have investigated different configurations for birefringence visualization and believe the circular polariscope is most useful for inspection of injection-molded plastic optics. In an effort to decrease birefringence effects, two experiments were conducted. They included: (1) annealing of the optics after fabrication and (2) modifying the injection molding prameters (packing pressures, injection rates, and hold time). While the second technique showed improvement, the annealing process could not improve quality without physically warping the lenses. Therefore, to effectively reduce flow-induced birefringence, molding conditions have to be carefully selected. These parameters are strongly connected to the physical part geometry. Both optical design and fabrication technology have to be considered together to deliver low birefringence while maintaining the required manufacturing tolerances. In this paper we present some of our current results that illustrate how flow-induced birefringence can degrade high performance injection-molded plastic optical systems.

  15. Variably spaced superlattice energy filter, a new device design concept for high-energy electron injection

    NASA Technical Reports Server (NTRS)

    Summers, C. J.; Brennan, K. F.

    1986-01-01

    A new variably spaced superlattice energy filter is proposed which provides high-energy injection of electrons into a bulk semiconductor layer based on resonant tunneling between adjacent quantum well levels which are brought into alignment by an applied bias. Applications of this concept to a variety of optoelectronic devices and to thin-film electroluminescent devices and photodetectors are discussed.

  16. Investigating high-concentration monoclonal antibody powder suspension in nonaqueous suspension vehicles for subcutaneous injection.

    PubMed

    Bowen, Mayumi; Armstrong, Nick; Maa, Yuh-Fun

    2012-12-01

    Developing high-concentration monoclonal antibody (mAb) liquid formulations for subcutaneous (s.c.) administration is challenging because increased viscosity makes injection difficult. To overcome this obstacle, we investigated a nonaqueous powder suspension approach. Three IgG1 mAbs were spray dried and suspended at different concentrations in Miglyol® 840, benzyl benzoate, or ethyl lactate. Suspensions were characterized for viscosity, particle size, and syringeability; physical stability was visually inspected. Suspensions generally outperformed liquid solutions for injectability despite higher viscosity at the same mAb concentrations. Powder formulations and properties had little effect on viscosity or injectability. Ethyl lactate suspensions had lowest viscosity (<20 cP) and lowest syringe injection glide force (<15 N) at mAb concentrations as high as 333 mg/mL (500 mg powder/mL). Inverse gas chromatography analysis indicated that the vehicle was the most important factor impacting suspension performance. Ethyl lactate rendered greater heat of sorption (suggesting strong particle-suspension vehicle interaction may reduce particle-particle self-association, leading to low suspension viscosity and glide force) but lacked the physical suspension stability exhibited by the other vehicles. Specific mixtures of ethyl lactate and Miglyol® 840 improved overall performance in high mAb concentration suspensions. This study demonstrated the viability of high mAb concentration (>300 mg/mL) in suspension formulations for s.c. administration. PMID:23001898

  17. Properties of high density polyethylene – Paulownia wood flour composites via injection molding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Paulownia wood (PW) flour is evaluated as a bio-based fiber reinforcement. Composites of high density polyethylene (HDPE), 25% by weight of PW, and either 0% or 5% by weight of maleated polyethylene (MAPE) were produced by twin screw compounding followed by injection molding. Molded test composite...

  18. Physics based simulation of seismicity induced in the vicinity of a high-pressure fluid injection

    NASA Astrophysics Data System (ADS)

    McCloskey, J.; NicBhloscaidh, M.; Murphy, S.; O'Brien, G. S.; Bean, C. J.

    2013-12-01

    High-pressure fluid injection into subsurface is known, in some cases, to induce earthquakes in the surrounding volume. The increasing importance of ';fracking' as a potential source of hydrocarbons has made the seismic hazard from this effect an important issue the adjudication of planning applications and it is likely that poor understanding of the process will be used as justification of refusal of planning in Ireland and the UK. Here we attempt to understand some of the physical controls on the size and frequency of induced earthquakes using a physics-based simulation of the process and examine resulting earthquake catalogues The driver for seismicity in our simulations is identical to that used in the paper by Murphy et al. in this session. Fluid injection is simulated using pore fluid movement throughout a permeable layer from a high-pressure point source using a lattice Boltzmann scheme. Diffusivities and frictional parameters can be defined independently at individual nodes/cells allowing us to reproduce 3-D geological structures. Active faults in the model follow a fractal size distribution and exhibit characteristic event size, resulting in a power-law frequency-size distribution. The fluid injection is not hydraulically connected to the fault (i.e. fluid does not come into physical contact with the fault); however stress perturbations from the injection drive the seismicity model. The duration and pressure-time function of the fluid injection can be adjusted to model any given injection scenario and the rate of induced seismicity is controlled by the local structures and ambient stress field as well as by the stress perturbations resulting from the fluid injection. Results from the rate and state fault models of Murphy et al. are incorporated to include the effect of fault strengthening in seismically quite areas. Initial results show similarities with observed induced seismic catalogues. Seismicity is only induced where the active faults have not been

  19. Pre- and post-injection flow characterization in a heavy-duty diesel engine using high-speed PIV

    NASA Astrophysics Data System (ADS)

    Zegers, R. P. C.; Luijten, C. C. M.; Dam, N. J.; de Goey, L. P. H.

    2012-09-01

    High-speed particle image velocimetry (HS-PIV) using hollow microspheres has been applied to characterize the flow in a heavy-duty diesel engine during and after fuel injection. The injection timings were varied in the range representing those used in premixed charge compression ignition (PCCI) regimes, and multiple injections have been applied to investigate their influence on the flow inside the combustion chamber. By injecting into pure nitrogen, combustion is avoided and the flow can be studied long after injection. The results show a sudden change of air motion at the start of injection as a result of the air entrainment at the core of the spray. Furthermore, as expected, spray injection causes a considerable increase in the cycle-to-cycle fluctuations of the flow pattern, the more so for longer injection durations.

  20. Optical injection and spectral filtering of high-power ultraviolet laser diodes.

    PubMed

    Schäfer, V M; Ballance, C J; Tock, C J; Lucas, D M

    2015-09-15

    We demonstrate injection locking of high-power laser diodes operating at 397 nm. We achieve stable operation with an injection power of ∼100  μW and a slave laser output power of up to 110 mW. We investigate the spectral purity of the slave laser light via photon scattering experiments on a single trapped (40)Ca(+) ion. We show that it is possible to achieve a scattering rate indistinguishable from that of monochromatic light by filtering the laser light with a diffraction grating to remove amplified spontaneous emission. PMID:26371912

  1. Performance of a High-Speed Compression-Ignition Engine Using Multiple Orifice Fuel Injection Nozzles

    NASA Technical Reports Server (NTRS)

    Spanogle, J A; Foster, H H

    1930-01-01

    This report presents test results obtained at the Langley Memorial Aeronautical Laboratory of the National Advisory Committee for Aeronautics during an investigation to determine the relative performance of a single-cylinder, high-speed, compression-ignition engine when using fuel injection valve nozzles with different numbers, sizes, and directions of round orifices. A spring-loaded, automatic injection valve was used, centrally located at the top of a vertical disk-type combustion chamber formed between horizontally opposed inlet and exhaust valves of a 5 inch by 7 inch engine.

  2. Interstitial injection in silicon after high-dose, low-energy arsenic implantation and annealing

    SciTech Connect

    Tsamis, C.; Skarlatos, D.; BenAssayag, G.; Claverie, A.; Lerch, W.; Valamontes, V.

    2005-11-14

    In this work, we investigate the interstitial injection into the silicon lattice due to high-dose, low-energy arsenic implantation. The approach consists in monitoring the diffusion of the arsenic profile as well as of the boron profile in buried {delta}-doped layers, when amounts of the as-implanted arsenic profile are removed by low-temperature wet silicon etching. The experimental results indicate that the contribution of the implantation damage to the transient enhanced diffusion of boron, and thus the interstitial injection, is not the main one. On the contrary, interstitial generation due to arsenic clustering seems to be more important for the present conditions.

  3. Investigation of caprock integrity during high-volume injection into the Utsira formation

    NASA Astrophysics Data System (ADS)

    Gasda, S. E.; Wangen, M.; Bjørnarå, T. I.

    2015-12-01

    The Utsira formation is a large offshore saline aquifer in the North Sea that is considered a likely candidate for storage of CO2 emissions. Currently, the Utsira is host to the longest operating CO2 storage project, the Sleipner project, which has injected 1 Mt CO2/y since 1996. The entire Utsira formation has an estimated storage capacity of 15 Gt, which is equal to 300 Sleipner-sized projects in simultaneous operation for the next 50 years. Injectivity into the Utsira is exceptionally good, and no pressurization has been observed at Sleipner. The formation is over 100-m thick and comprised of unconsolidated sand with high porosity and permeability (30-40% and 1-3 Darcy). The Nordland shale has been characterized as a high-quality seal that is regionally thick, extensive and absent of significant faults. Significant scale-up of CO2 injection into the Utsira is required to increase storage of regional CO2 emissions well beyond what is currently stored today. Full utilization of the Utsira storage capacity would result in injection rates >100 Mt/y, significantly larger than Sleipner. Despite the lack of pressure effects at Sleipner, higher injection rates will likely lead to pressure build-up in the Utsira. Relatively little is known about the magnitude of pressure build-up and resulting impact on caprock integrity with high-volume injection. The problem is complex, involving multiphase flow and mechanical deformation of the storage reservoir and the surrounding formations, and covers large spatial scales, ranging several hundred kilometers in lateral extent. There are significant challenges in applying fully coupled hydromechanical simulators to problems of this scale. The computational effort required to solve a resolved is significant, and efforts to reduce the complexity of the model are needed. In this study, simplified modeling approaches are investigated. A reduced order multiphase flow model coupled with a geomechanical model results in greater efficiency

  4. Development of High Efficiency and Low Emission Low Temperature Combustion Diesel Engine with Direct EGR Injection

    NASA Astrophysics Data System (ADS)

    Ho, R. J.; Kumaran, P.; Yusoff, M. Z.

    2016-03-01

    Focus on energy and environmental sustainability policy has put automotive research & development directed to developing high efficiency and low pollutant power train. Diffused flame controlled diesel combustion has reach its limitation and has driven R&D to explore other modes of combustions. Known effective mode of combustion to reduce emission are Low temperature combustion (LTC) and homogeneous charge combustion ignition by suppressing Nitrogen Oxide(NOx) and Particulate Matter (PM) formation. The key control to meet this requirement are chemical composition and distribution of fuel and gas during a combustion process. Most research to accomplish this goal is done by manipulating injected mass flow rate and varying indirect EGR through intake manifold. This research paper shows viable alternative direct combustion control via co-axial direct EGR injection with fuel injection process. A simulation study with OpenFOAM is conducted by varying EGR injection velocity and direct EGR injector diameter performed with under two conditions with non-combustion and combustion. n-heptane (C7H16) is used as surrogate fuel together with 57 species 290 semi-detailed chemical kinetic model developed by Chalmers University is used for combustion simulation. Simulation result indicates viability of co-axial EGR injection as a method for low temperature combustion control.

  5. Malnutrition alters the cardiovascular responses induced by central injection of tityustoxin in Fischer rats.

    PubMed

    Silva, Fernanda Cacilda Santos; Guidine, Patrícia Alves; Ribeiro, Mara Fernandes; Fernandes, Luciano Gonçalves; Xavier, Carlos Henrique; de Menezes, Rodrigo Cunha; Silva, Marcelo Eustáquio; Moraes-Santos, Tasso; Moraes, Márcio Flávio; Chianca, Deoclécio Alves

    2013-12-15

    Scorpion envenoming and malnutrition are considered two important public health problems in Brazil, involving mainly children. Both these conditions are more common among the economically stratified lower income portion of the population, thus suggesting that these factors should be analyzed concomitantly. It is known that cardiorespiratory manifestations, as cardiac arrhythmias, arterial hypertension and hypotension, pulmonary edema and circulatory failure are the main "causa mortis" of scorpion envenomation. Additionally, there are evidences in the literature that deficiencies in dietary intake endanger the CNS and modify the cardiovascular homeostasis. Then, the objective of this work is to evaluate the protein malnourished effect on cardiovascular responses induced by tityustoxin (TsTX, an α-type toxin extracted from the Tityus serrulatus scorpion venom). Fischer rats (n = 20) were injected i.c.v. with TsTX and divided in control and malnorished groups, which were, respectively, submitted to a control and a low-protein diet. Arterial pressure recordings were done until death of the animals. Although both groups presented an increased mean arterial pressure after TsTX injection, this increase was smaller and delayed in malnourished rats, when compared to control rats. In addition, heart rate increased only in rats from the control group. Finally, malnourished rats had an increase in survival time (9:9/13.5 vs. 15.5:10.5/18 min; p = 0.0009). In summary, our results suggest that the protein restriction attenuates the cardiovascular manifestations resulting from TsTX action on CNS. PMID:24060375

  6. Analysis of gas turbine engines using water and oxygen injection to achieve high Mach numbers and high thrust

    NASA Technical Reports Server (NTRS)

    Henneberry, Hugh M.; Snyder, Christopher A.

    1993-01-01

    An analysis of gas turbine engines using water and oxygen injection to enhance performance by increasing Mach number capability and by increasing thrust is described. The liquids are injected, either separately or together, into the subsonic diffuser ahead of the engine compressor. A turbojet engine and a mixed-flow turbofan engine (MFTF) are examined, and in pursuit of maximum thrust, both engines are fitted with afterburners. The results indicate that water injection alone can extend the performance envelope of both engine types by one and one-half Mach numbers at which point water-air ratios reach 17 or 18 percent and liquid specific impulse is reduced to some 390 to 470 seconds, a level about equal to the impulse of a high energy rocket engine. The envelope can be further extended, but only with increasing sacrifices in liquid specific impulse. Oxygen-airflow ratios as high as 15 percent were investigated for increasing thrust. Using 15 percent oxygen in combination with water injection at high supersonic Mach numbers resulted in thrust augmentation as high as 76 percent without any significant decrease in liquid specific impulse. The stoichiometric afterburner exit temperature increased with increasing oxygen flow, reaching 4822 deg R in the turbojet engine at a Mach number of 3.5. At the transonic Mach number of 0.95 where no water injection is needed, an oxygen-air ratio of 15 percent increased thrust by some 55 percent in both engines, along with a decrease in liquid specific impulse of 62 percent. Afterburner temperature was approximately 4700 deg R at this high thrust condition. Water and/or oxygen injection are simple and straightforward strategies to improve engine performance and they will add little to engine weight. However, if large Mach number and thrust increases are required, liquid flows become significant, so that operation at these conditions will necessarily be of short duration.

  7. Injection repair of advanced aircraft composites with a high temperature cyanate ester resin

    NASA Astrophysics Data System (ADS)

    Bauer, Amy Elizabeth

    Polymer matrix composites, especially those with carbon fiber reinforcement, are becoming increasingly common in aerospace applications due to their high stiffness to weight ratio, resulting in significant weight and fuel savings on commercial and military aircraft. Despite their excellent properties, carbon fiber composites are often susceptible to damage in the form of delaminations or interlaminar cracking caused by low energy impact or manufacturing defects. Often not easily detectable, delaminations are detrimental to the strength of the composite and can ultimately result in failure of the component. Therefore methods must be developed to repair damaged composites. Injection repair is a procedure that involves injecting a low viscosity resin into the damaged area and subjecting the composite to heat to cure the resin. Currently, injection repairs are rarely used in high temperature applications because of the lack of resins with both low viscosity and high thermal stability. Therefore demonstrating the use of a resin with satisfactory viscosity and Tg requirements would expand the application of injection repairs to more vigorous environments. In the present study, the injection repair method was developed to repair damaged bismaleimide carbon fiber composites that are similar to composites used on several high temperature weapon platforms. Bisphenol E cyanate ester (BECy) was chosen as the injection resin due to having the unique combination of low viscosity and a high glass transition temperature. Cure kinetic studies found an optimum undercure schedule to achieve the maximum T g while avoiding the high temperature postcure. Mechanical and adhesive tests revealed that partially cured BECy had properties superior to that of the fully cured resin. Following the evaluation of the resin, the injection repair procedure and set up were developed. Successful and reproducible repairs were performed on panels pre-damaged through static loading and drop tower impact

  8. High Frequency ELM Pacing by Lithium Pellet Injection on DIII-D

    NASA Astrophysics Data System (ADS)

    Bortolon, A.; Maingi, R.; Mansfield, D. K.; Nagy, A.; Roquemore, A. L.; Lunsford, R.; Jackson, G. L.; Osborne, T. H.; Parks, P. B.

    2015-11-01

    Full-shot, high-frequency pacing of edge localized modes (ELM) by lithium pellet injection has been demonstrated in DIII-D. A Lithium Granule Injector (LGI), recently installed on DIII-D to study pacing efficiency dependence on granule size and velocity, was tested in different ELMy scenarios (βN = 1.2-2.0) injecting granules of nominal diameter 0.3-0.9 mm, with injection speed 50-120 m/s and injection rates up to 500 Hz. Robust ELM pacing was documented on time windows up to 3.5 s, with triggering efficiency close to 100% obtained with 0.9 mm diameter granules, lower with smaller sizes and weakly dependent on granule velocity. Paced ELM frequencies up to 100 Hz were achieved, with a 2-5 fold increase over the natural ELM frequency and a consequent reduction of divertor peak heat flux. Overall, LGI high frequency pacing appeared to be compatible with high plasma performance, in terms of global confinement and pedestal characteristics. Work supported by the US Department of Energy under DE-AC02-09CH11466, DE-FC02-04ER54698.

  9. Effect of Fuel Injection and Mixing Characteristics on Pulse-Combustor Performance at High-Pressure

    NASA Technical Reports Server (NTRS)

    Yungster, Shaye; Paxson, Daniel E.; Perkins, Hugh D.

    2014-01-01

    Recent calculations of pulse-combustors operating at high-pressure conditions produced pressure gains significantly lower than those observed experimentally and computationally at atmospheric conditions. The factors limiting the pressure-gain at high-pressure conditions are identified, and the effects of fuel injection and air mixing characteristics on performance are investigated. New pulse-combustor configurations were developed, and the results show that by suitable changes to the combustor geometry, fuel injection scheme and valve dynamics the performance of the pulse-combustor operating at high-pressure conditions can be increased to levels comparable to those observed at atmospheric conditions. In addition, the new configurations can significantly reduce the levels of NOx emissions. One particular configuration resulted in extremely low levels of NO, producing an emission index much less than one, although at a lower pressure-gain. Calculations at representative cruise conditions demonstrated that pulse-combustors can achieve a high level of performance at such conditions.

  10. High injection phenomena in p/plus/in/plus/ silicon solar cells

    NASA Astrophysics Data System (ADS)

    Luque, A.; Equren, J.

    1982-08-01

    A simple analysis of p(plus)in(plus) solar cell structures is undertaken on the basis of the quasi-neutrality condition (n equals p). It is noted that the only differential equation to be solved in the model is the one of classical continuity. Only in the boundary conditions do nonlinearities appear. It is shown that the model can be applied to p(plus)nn(plus) or n(plus)pp(plus) cells under conditions of very high injection. High carrier concentractions are required to support the current flow even in short-circuit conditions, thereby enhancing the recombination (which is reduced by high injection lifetime increases). Under-linearity between the short-circuit current and the photon flux is deduced at very high irradiance. The short-circuit current under bifacial illumination is found to be higher than the sum of those currents under front and back illumination, thus leading to inherently better bifacial cells.

  11. Low and high affinity dopamine transporter inhibitors block dopamine uptake within 5 sec of intravenous injection

    PubMed Central

    Yorgason, Jordan T.; Jones, Sara R.; España, Rodrigo A.

    2011-01-01

    Extensive evidence suggests that the reinforcing effects of cocaine involve inhibition of dopamine transporters (DAT) and subsequent increases in dopamine (DA) levels in the striatum. We have previously reported that cocaine inhibits the DAT within 4–5 sec of intravenous injection, matching the temporal profile of the behavioral and subjective effects of cocaine. Intravenous injection of GBR-12909, a high affinity, long-acting DAT inhibitor, also inhibits DA uptake within 5 sec. Given that high affinity, long-acting drugs are considered to have relatively low abuse potential, we found it intriguing that GBR-12909 had an onset profile similar to that of cocaine. To further explore the onset kinetics of both low and high affinity DAT inhibitors, we examined the effects of intravenous cocaine (1.5 mg/kg), methylphenidate (1.5 mg/kg), nomifensine (1.5 mg/kg), GBR-12909 (1.5 mg/kg), PTT (0.5 mg/kg), and WF23 (0.5 mg/kg) on electrically-evoked DA release and uptake in the nucleus accumbens core. Results indicate that all of the DAT inhibitors significantly inhibited DA uptake within 5 sec of injection. However, the timing of peak uptake inhibition varied greatly between the low and high affinity uptake inhibitors. Uptake inhibition following cocaine, methylphenidate, and nomifensine peaked 30 sec following injection. In contrast, peak effects for GBR-12909, PTT, and WF23 occurred between 20 and 60 min following injection. These observations suggest that the initial onset for intravenous DAT inhibitors is extremely rapid and does not appear to be dictated by a drug’s affinity. PMID:21402130

  12. 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 ...

  13. 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 ...

  14. A micro powder injection molding apparatus for high aspect ratio metal micro-structure production

    NASA Astrophysics Data System (ADS)

    Fu, Gang; Tor, Shubeng; Loh, Ngiaphiang; Tay, Beeyen; Hardt, David E.

    2007-09-01

    A new variotherm molding apparatus is presented in this paper for the fabrication of high aspect ratio 316L stainless steel micro-structures using micro powder injection molding (μPIM) technology. The molding apparatus prototype includes an injection mold in which a silicon insert with an array of 24 × 24 (576) microcavities is mounted, a set of rapid tempering systems for the mold and a set of vacuum systems. The key advantage of this molding apparatus lies in the real-time monitoring and rapid adjustment of the mold cavity temperature during injection molding and part ejection, which makes molding and demolding of high aspect ratio green micro-structures possible. For example, incomplete filling occurs while injection molding micro-structures of 60 µm × height 191 µm with an aspect ratio of 3.2 using a conventional mold. In comparison, smaller micro-structures with higher aspect ratio are produced successfully in the case of the new molding apparatus, e.g. micro-structures of 40 µm × height 174 µm with an aspect ratio of 4.35 and 20 µm × height 160 µm with an aspect ratio of 8 were molded successfully.

  15. Injectable Polymerized High Internal Phase Emulsions with Rapid in Situ Curing

    PubMed Central

    2015-01-01

    Polymerized high internal phase emulsions (polyHIPEs) have been utilized in the creation of injectable scaffolds that cure in situ to fill irregular bone defects and potentially improve tissue healing. Previously, thermally initiated scaffolds required hours to cure, which diminished the potential for clinical translation. Here, a double-barrel syringe system for fabricating redox-initiated polyHIPEs with dramatically shortened cure times upon injection was demonstrated with three methacrylated macromers. The polyHIPE cure time, compressive properties, and pore architecture were investigated with respect to redox initiator chemistry and concentration. Increased concentrations of redox initiators reduced cure times from hours to minutes and increased the compressive modulus and strength without compromising the pore architecture. Additionally, storage of the uncured emulsion at reduced temperatures for 6 months was shown to have minimal effects on the resulting graft properties. These studies indicate that the uncured emulsions can be stored in the clinic until they are needed and then rapidly cured after injection to rigid, high-porosity scaffolds. In summary, we have improved upon current methods of generating injectable polyHIPE grafts to meet translational design goals of long storage times and rapid curing (<15 min) without sacrificing porosity or mechanical properties. PMID:25006990

  16. Experimental and numerical analysis of high-resolution injection technique for capillary electrophoresis microchip.

    PubMed

    Chang, Chin-Lung; Leong, Jik-Chang; Hong, Ting-Fu; Wang, Yao-Nan; Fu, Lung-Ming

    2011-01-01

    This study presents an experimental and numerical investigation on the use of high-resolution injection techniques to deliver sample plugs within a capillary electrophoresis (CE) microchip. The CE microfluidic device was integrated into a U-shaped injection system and an expansion chamber located at the inlet of the separation channel, which can miniize the sample leakage effect and deliver a high-quality sample plug into the separation channel so that the detection performance of the device is enhanced. The proposed 45° U-shaped injection system was investigated using a sample of Rhodamine B dye. Meanwhile, the analysis of the current CE microfluidic chip was studied by considering the separation of Hae III digested ϕx-174 DNA samples. The experimental and numerical results indicate that the included 45° U-shaped injector completely eliminates the sample leakage and an expansion separation channel with an expansion ratio of 2.5 delivers a sample plug with a perfect detection shape and highest concentration intensity, hence enabling an optimal injection and separation performance. PMID:21747696

  17. Elimination of fuel pressure fluctuation and multi-injection fuel mass deviation of high pressure common-rail fuel injection system

    NASA Astrophysics Data System (ADS)

    Li, Pimao; Zhang, Youtong; Li, Tieshuan; Xie, Lizhe

    2015-03-01

    The influence of fuel pressure fluctuation on multi-injection fuel mass deviation has been studied a lot, but the fuel pressure fluctuation at injector inlet is still not eliminated efficiently. In this paper, a new type of hydraulic filter consisting of a damping hole and a chamber is developed for elimination of fuel pressure fluctuation and multi-injection fuel mass deviation. Linear model of the improved high pressure common-rail system(HPCRS) including injector, the pipe connecting common-rail with injector and the hydraulic filter is built. Fuel pressure fluctuation at injector inlet, on which frequency domain analysis is conducted through fast Fourier transformation, is acquired at different target pressure and different damping hole diameter experimentally. The linear model is validated and can predict the natural frequencies of the system. Influence of damping hole diameter on fuel pressure fluctuation is analyzed qualitatively based on the linear model, and it can be inferred that an optimal diameter of the damping hole for elimination of fuel pressure fluctuation exists. Fuel pressure fluctuation and fuel mass deviation under different damping hole diameters are measured experimentally, and it is testified that the amplitude of both fuel pressure fluctuation and fuel mass deviation decreases first and then increases with the increasing of damping hole diameter. The amplitude of main injection fuel mass deviation can be reduced by 73% at most under pilot-main injection mode, and the amplitude of post injection fuel mass deviation can be reduced by 92% at most under main-post injection mode. Fuel mass of a single injection increases with the increasing of the damping hole diameter. The hydraulic filter proposed by this research can be potentially used to eliminate fuel pressure fluctuation at injector inlet and improve the stability of HPCRS fuel injection.

  18. Effect of in ovo injection with selenium on immune and antioxidant responses during experimental necrotic enteritis in broiler chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Selenium (Se) is an essential component of several major metabolic pathways in the antioxidant enzymes activity and modulating immune system. This study was conducted to investigate the effects of in ovo injection of selenium (Se) on modulating the immune system and antioxidant responses in chickens...

  19. MICROBIAL RESPONSES TO IN SITU CHEMICAL OXIDATION, SIX-PHASE HEATING, AND STEAM INJECTION REMEDIATION TECHNOLOGIES IN GROUND WATER

    EPA Science Inventory

    The evaluation of microbial responses to three in situ source removal remedial technologies including permanganate-based in-situ chemical oxidation (ISCO), six-phase heating (SPH), and steam injection (SI) was performed at Cape Canaveral Air Station in Florida. The investigatio...

  20. Responsibility attribution of HIV infection and coping among injection drug users in Malaysia.

    PubMed

    Chou, Chih-Chin; Chronister, Julie; Chou, Chih-Hung; Tan, Sooyin; Macewicz, Thomas

    2013-01-01

    This study explored responsibility attribution (RA) of HIV/AIDS infection (i.e., how an individual perceives the cause of their HIV/AIDS infection) and its relationship to coping styles among injection drug users (IDUs) with HIV/AIDS. In addition, this study investigated whether self-esteem, social support, and religiosity mediate the relationship between RA and coping styles of IDUs with HIV/AIDS. Participants were 201 adult IDUs with HIV/AIDS participating in the National Drug Rehabilitation Center in Malaysia. Five measures were used to assess the above constructs. Cluster analysis, analysis of variance, and mediation analyses were conducted. Results of this study indicated that IDUs with HIV/AIDS in Malaysia can be classified into four homogenous attribution groups: external, fatalistic, internal, and indeterminate. Mediator analyses revealed that combination of self-esteem, social support, and religiosity mediate the relationship between RA and coping behaviors. Clinicians working with IDUs with HIV/AIDS need to address the role of RA, self-esteem, religiosity, and social support as these psychosocial constructs are linked to coping with HIV/AIDS. Future researchers should investigate whether enhancing self-esteem, social support, and religiosity can promote active problem-solving coping and reduce the use of avoidance coping behaviors. PMID:23713718

  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. High-rate injection is associated with the increase in U.S. mid-continent seismicity

    NASA Astrophysics Data System (ADS)

    Weingarten, M.; Ge, S.; Godt, J. W.; Bekins, B. A.; Rubinstein, J. L.

    2015-06-01

    An unprecedented increase in earthquakes in the U.S. mid-continent began in 2009. Many of these earthquakes have been documented as induced by wastewater injection. We examine the relationship between wastewater injection and U.S. mid-continent seismicity using a newly assembled injection well database for the central and eastern United States. We find that the entire increase in earthquake rate is associated with fluid injection wells. High-rate injection wells (>300,000 barrels per month) are much more likely to be associated with earthquakes than lower-rate wells. At the scale of our study, a well’s cumulative injected volume, monthly wellhead pressure, depth, and proximity to crystalline basement do not strongly correlate with earthquake association. Managing injection rates may be a useful tool to minimize the likelihood of induced earthquakes.

  3. High-rate injection is associated with the increase in U.S. mid-continent seismicity

    USGS Publications Warehouse

    Weingarten, Matthew; Ge, Shemin; Godt, Jonathan W.; Bekins, Barbara A.; Rubinstein, Justin L.

    2015-01-01

    An unprecedented increase in earthquakes in the U.S. mid-continent began in 2009. Many of these earthquakes have been documented as induced by wastewater injection. We examine the relationship between wastewater injection and U.S. mid-continent seismicity using a newly assembled injection well database for the central and eastern United States. We find that the entire increase in earthquake rate is associated with fluid injection wells. High-rate injection wells (>300,000 barrels per month) are much more likely to be associated with earthquakes than lower-rate wells. At the scale of our study, a well’s cumulative injected volume, monthly wellhead pressure, depth, and proximity to crystalline basement do not strongly correlate with earthquake association. Managing injection rates may be a useful tool to minimize the likelihood of induced earthquakes.

  4. INDUCED SEISMICITY. High-rate injection is associated with the increase in U.S. mid-continent seismicity.

    PubMed

    Weingarten, M; Ge, S; Godt, J W; Bekins, B A; Rubinstein, J L

    2015-06-19

    An unprecedented increase in earthquakes in the U.S. mid-continent began in 2009. Many of these earthquakes have been documented as induced by wastewater injection. We examine the relationship between wastewater injection and U.S. mid-continent seismicity using a newly assembled injection well database for the central and eastern United States. We find that the entire increase in earthquake rate is associated with fluid injection wells. High-rate injection wells (>300,000 barrels per month) are much more likely to be associated with earthquakes than lower-rate wells. At the scale of our study, a well's cumulative injected volume, monthly wellhead pressure, depth, and proximity to crystalline basement do not strongly correlate with earthquake association. Managing injection rates may be a useful tool to minimize the likelihood of induced earthquakes. PMID:26089509

  5. 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 ...

  6. Laser Injection Optics for High-Intensity Transmission in Multimode Fibers

    SciTech Connect

    SETCHELL,ROBERT E.

    2000-08-29

    An increasing number of applications are requiring fiber transmission of high-intensity laser pulses. The authors particular interests have led them to examine carefully the fiber transmission of Q-switched pulses from multimode Nd:YAG lasers at their fundamental wavelength. The maximum pulse energy that can be transmitted through a particular fiber is limited by the onset of laser-induced breakdown and damage mechanisms. Laser breakdown at the fiber entrance face is often the first limiting process to be encountered, but other mechanisms can result in catastrophic damage at either fiber face, within the initial entry segment of the fiber, and at other internal sites along the fiber path. In the course of their studies they have examined a number of factors that govern the relative importance of different mechanisms, including laser characteristics, the design and alignment of injection optics, fiber end-face preparation, and fiber routing. The present study emphasizes the important criteria for injection optics in high-intensity fiber transmission, and illustrates the opportunities that now exist for innovative designs of optics to meet these criteria. The consideration of diffractive optics to achieve desired injection criteria began in 1993, and they have evaluated a progression of designs since that time. In the present study, two recent designs for injection optics are compared by testing a sufficient number of fibers with each design to establish statistics for the onset of laser-induced breakdown and damage. In this testing they attempted to hold constant other factors that can influence damage statistics. Both designs performed well, although one was less successful in meeting all injection criteria and consequently showed a susceptibility to a particular damage process.

  7. Pneumatic Microvalve-Based Hydrodynamic Sample Injection for High-Throughput, Quantitative Zone Electrophoresis in Capillaries

    SciTech Connect

    Kelly, Ryan T.; Wang, Chenchen; Rausch, Sarah J.; Lee, Cheng S.; Tang, Keqi

    2014-07-01

    A hybrid microchip/capillary CE system was developed to allow unbiased and lossless sample loading and high throughput repeated injections. This new hybrid CE system consists of a polydimethylsiloxane (PDMS) microchip sample injector featuring a pneumatic microvalve that separates a sample introduction channel from a short sample loading channel and a fused silica capillary separation column that connects seamlessly to the sample loading channel. The sample introduction channel is pressurized such that when the pneumatic microvalve opens briefly, a variable-volume sample plug is introduced into the loading channel. A high voltage for CE separation is continuously applied across the loading channel and the fused silica capillary separation column. Analytes are rapidly separated in the fused silica capillary with high resolution. High sensitivity MS detection after CE separation is accomplished via a sheathless CE/ESI-MS interface. The performance evaluation of the complete CE/ESI-MS platform demonstrated that reproducible sample injection with well controlled sample plug volumes could be achieved by using the PDMS microchip injector. The absence of band broadening from microchip to capillary indicated a minimum dead volume at the junction. The capabilities of the new CE/ESI-MS platform in performing high throughput and quantitative sample analyses were demonstrated by the repeated sample injection without interrupting an ongoing separation and a good linear dependence of the total analyte ion abundance on the sample plug volume using a mixture of peptide standards. The separation efficiency of the new platform was also evaluated systematically at different sample injection times, flow rates and CE separation voltages.

  8. Effects of low charge injection densities on corrosion responses of pulsed 316LVM stainless steel electrodes.

    PubMed

    Riedy, L W; Walter, J S

    1996-06-01

    The safe charge injection density for pulsing of 316LVM electrodes has been reported to be 40 microC/cm2. However, only 20 microC/cm2 is available for nonfaradic charge transfer and double layer charge injection. Therefore, we evaluated long term pulsing at 20 microC/cm2 with capacitor coupling. PMID:8987272

  9. High SO{sub 2} removal duct injection: A low-cost FGD alternative

    SciTech Connect

    Nelson, S.G.

    1995-12-01

    Sorbent Technologies Corporation, of the United States, is currently developing and demonstrating a new waste free, retrofitable, high-SO{sub 2} removal duct-injection process. Up to 85 percent SO{sub 2} removal is achieved by simply injecting a new dry lime-based sorbent into the flue-gas duct, collecting the sorbent downstream in a particulate collector, and then recycling the sorbent. By avoiding large, expensive components, the process can have low capital costs, making it especially appropriate for smaller, older, less-utilized plants. The key to the new technology is the use of sorbent supports. Supported sorbents are produced by coating hydrated lime onto inexpensive mineral supports, such as exfoliated vermiculite or perlite. Consequently, there are no liquid, sludge, or solid wastes with the new technology. Once saturated with SO{sub 2}, the spent sorbent can be easily pelletized into a valuable soil-conditioning agricultural by-product, for the sustainable development that the future requires. This paper describes Sorbent Technologies` pilot demonstration of supported sorbent injection at the Ohio Edison Company`s R.E. Burger station. The Burger effort is also the first demonstration of the Electric Power Research Institute`s new {open_quotes}COHPAC{close_quotes} baghouse technology in a sorbent-injection desulfurization application.

  10. Control of high-Z PFC erosion by local gas injection in DIII-D

    NASA Astrophysics Data System (ADS)

    Rudakov, D. L.; Stangeby, P. C.; Wong, C. P. C.; McLean, A. G.; Wampler, W. R.; Watkins, J. G.; Boedo, J. A.; Briesemeister, A.; Buchenauer, D. A.; Chrobak, C. P.; Elder, J. D.; Fenstermacher, M. E.; Guo, H. Y.; Lasnier, C. J.; Leonard, A. W.; Maingi, R.; Moyer, R. A.

    2015-08-01

    Reduced erosion of a high-Z PFC divertor surface was observed in DIII-D with local injection of methane and deuterium gases. Molybdenum-coated silicon samples were exposed in the lower divertor of DIII-D using DiMES under plasma conditions previously shown to cause significant net erosion of Mo. Three exposures with 13CH4 and one exposure with D2 gas injection about 12 cm upstream of the samples located within 1-2 cm of the attached strike point were performed. Reduction of Mo erosion was evidenced in-situ by the suppression of MoI line radiation at 386.4 nm once the gas injection started. Post-mortem ion beam analysis demonstrated that the net erosion of molybdenum near the center of the samples exposed with 13CH4 injection was below the measurement resolution of 0.5 nm, corresponding to a rate of ⩽0.04 nm/s. Compared to the previously measured erosion rates, this constitutes a reduction by a factor of >10.

  11. Are females who inject drugs at higher risk for HIV infection than males who inject drugs: an international systematic review of high seroprevalence areas

    PubMed Central

    Des Jarlais, Don C; Feelemyer, Jonathan P; Modi, Shilpa N.; Arasteh, Kamyar; Hagan, Holly

    2012-01-01

    Objective There are multiple reasons why females who inject drugs may be more likely to become infected with HIV than males who inject drugs. Where this is the case, special HIV prevention programs for females would be needed. Design International systematic review and meta-analysis of studies across 14 countries. Methods Countries with high seroprevalence (>20%) HIV epidemics among persons who inject drugs (PWID) were identified from the Reference Group to the UN on HIV and Injecting Drug Use. Systematic literature reviews collected data on HIV prevalence by gender for these countries. Non-parametric and parametric tests along with meta-analytic techniques examined heterogeneity and differences in odds ratios (OR) across studies. Results Data were abstracted from 117 studies in 14 countries; total sample size N=128,745. The mean weighted OR for HIV prevalence among females to males was 1.18 [95% CI 1.10–1.26], with high heterogeneity among studies (I2 = 70.7%). There was a Gaussian distribution of the log ORs across studies in the sample. Conclusion There was a significantly higher HIV prevalence among females compared to males who inject drugs in high seroprevalence settings, but the effect size is extremely modest. The high level of heterogeneity and the Gaussian distribution suggest multiple causes of differences in HIV prevalence between females and males, with a specific difference determined by local factors. Greater understanding of factors that may protect females from HIV infection may provide insights into more effective HIV prevention for both females and males who inject drugs. PMID:22257753

  12. High domain wall velocities via spin transfer torque using vertical current injection

    PubMed Central

    Metaxas, Peter J.; Sampaio, Joao; Chanthbouala, André; Matsumoto, Rie; Anane, Abdelmadjid; Fert, Albert; Zvezdin, Konstantin A.; Yakushiji, Kay; Kubota, Hitoshi; Fukushima, Akio; Yuasa, Shinji; Nishimura, Kazumasa; Nagamine, Yoshinori; Maehara, Hiroki; Tsunekawa, Koji; Cros, Vincent; Grollier, Julie

    2013-01-01

    Domain walls, nanoscale transition regions separating oppositely oriented ferromagnetic domains, have significant promise for use in spintronic devices for data storage and memristive applications. The state of these devices is related to the wall position and thus rapid operation will require a controllable onset of domain wall motion and high speed wall displacement. These processes are traditionally driven by spin transfer torque due to lateral injection of spin polarized current through a ferromagnetic nanostrip. However, this geometry is often hampered by low maximum wall velocities and/or a need for prohibitively high current densities. Here, using time-resolved magnetotransport measurements, we show that vertical injection of spin currents through a magnetic tunnel junction can drive domain walls over hundreds of nanometers at ~500 m/s using current densities on the order of 6 MA/cm2. Moreover, these measurements provide information about the stochastic and deterministic aspects of current driven domain wall mediated switching. PMID:23670402

  13. High domain wall velocities via spin transfer torque using vertical current injection.

    PubMed

    Metaxas, Peter J; Sampaio, Joao; Chanthbouala, André; Matsumoto, Rie; Anane, Abdelmadjid; Fert, Albert; Zvezdin, Konstantin A; Yakushiji, Kay; Kubota, Hitoshi; Fukushima, Akio; Yuasa, Shinji; Nishimura, Kazumasa; Nagamine, Yoshinori; Maehara, Hiroki; Tsunekawa, Koji; Cros, Vincent; Grollier, Julie

    2013-01-01

    Domain walls, nanoscale transition regions separating oppositely oriented ferromagnetic domains, have significant promise for use in spintronic devices for data storage and memristive applications. The state of these devices is related to the wall position and thus rapid operation will require a controllable onset of domain wall motion and high speed wall displacement. These processes are traditionally driven by spin transfer torque due to lateral injection of spin polarized current through a ferromagnetic nanostrip. However, this geometry is often hampered by low maximum wall velocities and/or a need for prohibitively high current densities. Here, using time-resolved magnetotransport measurements, we show that vertical injection of spin currents through a magnetic tunnel junction can drive domain walls over hundreds of nanometers at ~500 m/s using current densities on the order of 6 MA/cm(2). Moreover, these measurements provide information about the stochastic and deterministic aspects of current driven domain wall mediated switching. PMID:23670402

  14. High domain wall velocities via spin transfer torque using vertical current injection

    NASA Astrophysics Data System (ADS)

    Metaxas, Peter J.; Sampaio, Joao; Chanthbouala, André; Matsumoto, Rie; Anane, Abdelmadjid; Fert, Albert; Zvezdin, Konstantin A.; Yakushiji, Kay; Kubota, Hitoshi; Fukushima, Akio; Yuasa, Shinji; Nishimura, Kazumasa; Nagamine, Yoshinori; Maehara, Hiroki; Tsunekawa, Koji; Cros, Vincent; Grollier, Julie

    2013-05-01

    Domain walls, nanoscale transition regions separating oppositely oriented ferromagnetic domains, have significant promise for use in spintronic devices for data storage and memristive applications. The state of these devices is related to the wall position and thus rapid operation will require a controllable onset of domain wall motion and high speed wall displacement. These processes are traditionally driven by spin transfer torque due to lateral injection of spin polarized current through a ferromagnetic nanostrip. However, this geometry is often hampered by low maximum wall velocities and/or a need for prohibitively high current densities. Here, using time-resolved magnetotransport measurements, we show that vertical injection of spin currents through a magnetic tunnel junction can drive domain walls over hundreds of nanometers at ~500 m/s using current densities on the order of 6 MA/cm2. Moreover, these measurements provide information about the stochastic and deterministic aspects of current driven domain wall mediated switching.

  15. Stable High-Quality Electron Bunch Generation via Counter-Crossing Injection

    SciTech Connect

    Kotaki, H.; Daito, I.; Kando, M.; Hayashi, Y.; Ma, J.; Chen, L.-M.; Esirkepov, T. Zh.; Fukuda, Y.; Homma, T.; Pirozhkov, A.; Koga, J. K.; Nakajima, K.; Daido, H.; Bulanov, S. V.

    2008-06-24

    We demonstrate a highly reproducible acceleration of a high-quality electron bunch injected into the laser wake field accelerator with the help of a counter-crossing laser pulse. In our experiments, the wake field is generated by a sub-relativistic laser pulse; the second laser pulse collides with the first pulse at 135 deg. realizing optical injection of electron bunch into the wake field. Since the second pulse is counter-crossing, it can not damage the laser system. The observed electron bunch has the energy of 14 MeV with a 11% (1.5 MeV) spread, the total charge of 22 pC, a normalized emittance not greater than 0.8{pi} mm mrad, and a reproducibility at least 50%.

  16. Injection locking of a high power ultraviolet laser diode for laser cooling of ytterbium atoms

    SciTech Connect

    Hosoya, Toshiyuki; Miranda, Martin; Inoue, Ryotaro; Kozuma, Mikio

    2015-07-15

    We developed a high-power laser system at a wavelength of 399 nm for laser cooling of ytterbium atoms with ultraviolet laser diodes. The system is composed of an external cavity laser diode providing frequency stabilized output at a power of 40 mW and another laser diode for amplifying the laser power up to 220 mW by injection locking. The systematic method for optimization of our injection locking can also be applied to high power light sources at any other wavelengths. Our system does not depend on complex nonlinear frequency-doubling and can be made compact, which will be useful for providing light sources for laser cooling experiments including transportable optical lattice clocks.

  17. ON THE INJECTION SPECTRUM OF RELATIVISTIC ELECTRONS IN HIGH-REDSHIFT RADIO GALAXIES

    SciTech Connect

    Gopal-Krishna; Mhaskey, Mukul

    2012-01-01

    We point out that the remarkable linearity of the ultra-steep radio spectra of high-redshift radio galaxies reflects a previously reported general trend for powerful radio galaxies, according to which the spectral curvature is less for sources having steeper spectra (measured near rest-frame 1 GHz). We argue based on existing theoretical and observational evidence that it is premature to conclude that the particle acceleration mechanism in sources having straight, ultra-steep radio spectra gives rise to an ultra-steep injection spectrum of the radiating electrons. In empirical support for this we show that the estimated injection spectral indices available for a representative sample of 35 compact steep spectrum radio sources are not correlated with their rest-frame (intrinsic) rotation measures, which are known to be typically large, indicating a dense environment, as is also the case for high-z radio galaxies.

  18. The devastating outcome of massive subcutaneous injection of highly viscous fluids in male-to-female transsexuals.

    PubMed

    Hage, J J; Kanhai, R C; Oen, A L; van Diest, P J; Karim, R B

    2001-03-01

    Illicit subcutaneous injections of massive quantities of highly viscous fluids are still performed, often by unqualified persons. Fifteen male-to-female transsexuals consulted the authors regarding their devastating long-term outcomes after the injection of up to 8 liters of alleged silicone or mineral oil to feminize their bodies. After a latency period of up to 17 years, these injections led to complications ranging from scarring and deformity to infections. These patients were treated conservatively for inflammation and infection or surgically by resection of the oil-infested areas. In view of the potential dangers, feminization by the injection of high-viscosity fluids should be soundly condemned. PMID:11304599

  19. Entanglement, EPR correlations, and mesoscopic quantum superposition by the high-gain quantum injected parametric amplification

    SciTech Connect

    Caminati, Marco; De Martini, Francesco; Perris, Riccardo; Secondi, Veronica; Sciarrino, Fabio

    2006-12-15

    We investigate the multiparticle quantum superposition and the persistence of bipartite entanglement of the output field generated by the quantum injected high-gain optical parametric amplification of a single photon. The physical configuration based on the optimal universal quantum cloning has been adopted to investigate how the entanglement and the quantum coherence of the system persists for large values of the nonlinear parametric gain g.

  20. Prediction of the Period of Swirl Motion Appearing in Gas Injection Processes at High Temperatures

    NASA Astrophysics Data System (ADS)

    Hiratsuka, Akira; Tsujino, Ryoji; Sasaki, Yasushi; Nishihara, Kazuyoshi; Iguchi, Manabu

    A swirl motion induced by gas injection through a bottom nozzle has high mixing ability and useful for the mixing of a molten steel bath in the refining processes. As one of the fundamental characteristics of the swirl motion, the period is mentioned in this study. A semi-empirical equation is proposed for the period of swirl motion by referring to the rotary sloshing appearing in a cylindrical vessel oscillated in the vertical or the horizontal direction.

  1. Apparatus for injecting high power laser light into a fiber optic cable

    DOEpatents

    Sweatt, W.C.

    1997-11-11

    High intensity laser light is evenly injected into an optical fiber by the combination of a converging lens and a multisegment kinoform (binary optical element). The segments preferably have multi-order gratings on each which are aligned parallel to a radial line emanating from the center of the kinoform and pass through the center of the element. The grating in each segment causes circumferential (lateral) dispersion of the light, thereby avoiding detrimental concentration of light energy within the optical fiber. 6 figs.

  2. HIGH RESOLUTION PREDICTION OF GAS INJECTION PROCESS PERFORMANCE FOR HETEROGENEOUS RESERVOIRS

    SciTech Connect

    Franklin M. Orr, Jr.

    2001-06-30

    This report outlines progress in the third 3 quarter of the first year of the DOE project ''High Resolution Prediction of Gas Injection Process Performance for Heterogeneous Reservoirs.'' A simple theoretical formulation of vertical flow with capillary/gravity equilibrium is described. Also reported are results of experimental measurements for the same systems. The results reported indicate that displacement behavior is strongly affected by the interfacial tension of phases that form on the tie line that extends through the initial oil composition.

  3. Local innate immune responses in the vaccine adjuvant-injected muscle.

    PubMed

    Liang, Frank; Loré, Karin

    2016-04-01

    Inducing a high magnitude of antibodies, possibly in combination with T-cell responses that offer epitope breadth over prolonged periods of time is likely a prerequisite for effective vaccines against severe diseases such as HIV-1 infection, malaria and tuberculosis. A much better understanding of the innate immune mechanisms that are critical for inducing desired responses to vaccination would help in the design of novel vaccines. The majority of human vaccines are administered into the muscle. In this brief review, we focus on the initial innate immune events that occur locally at the site of intramuscular vaccine delivery, and how they are influenced by clinically approved vaccine adjuvants. In particular, the effects on cell mobilization, cell activation and vaccine antigen uptake are reviewed. Understanding how distinct adjuvants enhance and tailor vaccine responses would facilitate the selection of the best-suited adjuvant to improve vaccine efficacy to a given pathogen. PMID:27195117

  4. Local innate immune responses in the vaccine adjuvant-injected muscle

    PubMed Central

    Liang, Frank; Loré, Karin

    2016-01-01

    Inducing a high magnitude of antibodies, possibly in combination with T-cell responses that offer epitope breadth over prolonged periods of time is likely a prerequisite for effective vaccines against severe diseases such as HIV-1 infection, malaria and tuberculosis. A much better understanding of the innate immune mechanisms that are critical for inducing desired responses to vaccination would help in the design of novel vaccines. The majority of human vaccines are administered into the muscle. In this brief review, we focus on the initial innate immune events that occur locally at the site of intramuscular vaccine delivery, and how they are influenced by clinically approved vaccine adjuvants. In particular, the effects on cell mobilization, cell activation and vaccine antigen uptake are reviewed. Understanding how distinct adjuvants enhance and tailor vaccine responses would facilitate the selection of the best-suited adjuvant to improve vaccine efficacy to a given pathogen. PMID:27195117

  5. Abnormal hemodynamic response to forepaw stimulation in rat brain after cocaine injection

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Park, Kicheon; Choi, Jeonghun; Pan, Yingtian; Du, Congwu

    2015-03-01

    Simultaneous measurement of hemodynamics is of great importance to evaluate the brain functional changes induced by brain diseases such as drug addiction. Previously, we developed a multimodal-imaging platform (OFI) which combined laser speckle contrast imaging with multi-wavelength imaging to simultaneously characterize the changes in cerebral blood flow (CBF), oxygenated- and deoxygenated- hemoglobin (HbO and HbR) from animal brain. Recently, we upgraded our OFI system that enables detection of hemodynamic changes in response to forepaw electrical stimulation to study potential brain activity changes elicited by cocaine. The improvement includes 1) high sensitivity to detect the cortical response to single forepaw electrical stimulation; 2) high temporal resolution (i.e., 16Hz/channel) to resolve dynamic variations in drug-delivery study; 3) high spatial resolution to separate the stimulation-evoked hemodynamic changes in vascular compartments from those in tissue. The system was validated by imaging the hemodynamic responses to the forepaw-stimulations in the somatosensory cortex of cocaine-treated rats. The stimulations and acquisitions were conducted every 2min over 40min, i.e., from 10min before (baseline) to 30min after cocaine challenge. Our results show that the HbO response decreased first (at ~4min) followed by the decrease of HbR response (at ~6min) after cocaine, and both did not fully recovered for over 30min. Interestingly, while CBF decreased at 4min, it partially recovered at 18min after cocaine administration. The results indicate the heterogeneity of cocaine's effects on vasculature and tissue metabolism, demonstrating the unique capability of optical imaging for brain functional studies.

  6. Highly Efficient Room Temperature Spin Injection Using Spin Filtering in MgO

    NASA Astrophysics Data System (ADS)

    Jiang, Xin

    2007-03-01

    Efficient electrical spin injection into GaAs/AlGaAs quantum well structures was demonstrated using CoFe/MgO tunnel spin injectors at room temperature. The spin polarization of the injected electron current was inferred from the circular polarization of electroluminescence from the quantum well. Polarization values as high as 57% at 100 K and 47% at 290 K were obtained in a perpendicular magnetic field of 5 Tesla. The interface between the tunnel spin injector and the GaAs interface remained stable even after thermal annealing at 400 ^oC. The temperature dependence of the electron-hole recombination time and the electron spin relaxation time in the quantum well was measured using time-resolved optical techniques. By taking into account of these properties of the quantum well, the intrinsic spin injection efficiency can be deduced. We conclude that the efficiency of spin injection from a CoFe/MgO spin injector is nearly independent of temperature and, moreover, is highly efficient with an efficiency of ˜ 70% for the temperature range studied (10 K to room temperature). Tunnel spin injectors are thus highly promising components of future semiconductor spintronic devices. Collaborators: Roger Wang^1, 3, Gian Salis^2, Robert Shelby^1, Roger Macfarlane^1, Seth Bank^3, Glenn Solomon^3, James Harris^3, Stuart S. P. Parkin^1 ^1 IBM Almaden Research Center, San Jose, CA 95120 ^2 IBM Zurich Research Laboratory, S"aumerstrasse 4, 8803 R"uschlikon, Switzerland ^3 Solid States and Photonics Laboratory, Stanford University, Stanford, CA 94305

  7. Tailpipe emissions from gasoline direct injection (GDI) and port fuel injection (PFI) vehicles at both low and high ambient temperatures.

    PubMed

    Zhu, Rencheng; Hu, Jingnan; Bao, Xiaofeng; He, Liqiang; Lai, Yitu; Zu, Lei; Li, Yufei; Su, Sheng

    2016-09-01

    Vehicle emissions are greatly influenced by various factors that are related to engine technology and driving conditions. Only the fuel injection method and ambient temperature are investigated in this research. Regulated gaseous and particulate matter (PM) emissions from two advanced gasoline-fueled vehicles, one with direct fuel injection (GDI) and the other with port fuel injection (PFI), are tested with conventional gasoline and ethanol-blended gasoline (E10) at both -7 °C and 30 °C. The total particle number (PN) concentrations and size distributions are monitored with an Electrical Low Pressure Impactor (ELPI(+)). The solid PN concentrations are measured with a condensation particle counter (CPC) after removing volatile matters through the particle measurement program (PMP) system. The results indicate that decreasing the ambient temperature from 30 °C to -7 °C significantly increases the fuel consumption and all measured emissions except for NOx. The GDI vehicle exhibits lower fuel consumption than the PFI vehicle but emits more total hydrocarbons (THC), PM mass and solid PN emissions at 30 °C. The adaptability of GDI technology appears to be better than that of PFI technology at low ambient temperature. For example, the CO, THC and PM mass emission factors of the PFI vehicle are higher than those of the GDI vehicle and the solid PN emission factors are comparable in the cold-start tests at -7 °C. Specifically, during start-up the particulate matter emissions of the PFI are much higher than the GDI. In most cases, the geometric mean diameter (GMD) of the accumulation mode particles is 58-86 nm for both vehicles, and the GMD of the nucleation mode particles is 10-20 nm. The results suggest that the gaseous and particulate emissions from the PFI vehicle should not be neglected compared to those from the GDI vehicle especially in a cold environment. PMID:27267738

  8. Murine precision-cut lung slices exhibit acute responses following exposure to gasoline direct injection engine emissions.

    PubMed

    Maikawa, Caitlin L; Zimmerman, Naomi; Rais, Khaled; Shah, Mittal; Hawley, Brie; Pant, Pallavi; Jeong, Cheol-Heon; Delgado-Saborit, Juana Maria; Volckens, John; Evans, Greg; Wallace, James S; Godri Pollitt, Krystal J

    2016-10-15

    Gasoline direct injection (GDI) engines are increasingly prevalent in the global vehicle fleet. Particulate matter emissions from GDI engines are elevated compared to conventional gasoline engines. The pulmonary effects of these higher particulate emissions are unclear. This study investigated the pulmonary responses induced by GDI engine exhaust using an ex vivo model. The physiochemical properties of GDI engine exhaust were assessed. Precision cut lung slices were prepared using Balb/c mice to evaluate the pulmonary response induced by one-hour exposure to engine-out exhaust from a laboratory GDI engine operated at conditions equivalent to vehicle highway cruise conditions. Lung slices were exposed at an air-liquid interface using an electrostatic aerosol in vitro exposure system. Particulate and gaseous exhaust was fractionated to contrast mRNA production related to polycyclic aromatic hydrocarbon (PAH) metabolism and oxidative stress. Exposure to GDI engine exhaust upregulated genes involved in PAH metabolism, including Cyp1a1 (2.71, SE=0.22), and Cyp1b1 (3.24, SE=0.12) compared to HEPA filtered air (p<0.05). GDI engine exhaust further increased Cyp1b1 expression compared to filtered GDI engine exhaust (i.e., gas fraction only), suggesting this response was associated with the particulate fraction. Exhaust particulate was dominated by high molecular weight PAHs. Hmox1, an oxidative stress marker, exhibited increased expression after exposure to GDI (1.63, SE=0.03) and filtered GDI (1.55, SE=0.04) engine exhaust compared to HEPA filtered air (p<0.05), likely attributable to a combination of the gas and particulate fractions. Exposure to GDI engine exhaust contributes to upregulation of genes related to the metabolism of PAHs and oxidative stress. PMID:27369091

  9. Determination of hexazinone in groundwater by direct-injection high-performance liquid chromatography.

    PubMed

    Perkins, L B; Bushway, R J; Katz, L E

    1999-01-01

    Hexazinone has been detected at levels ranging from 0.2 to 50 micrograms/L in many groundwater samples from eastern Maine over the past decade. A rapid and inexpensive direct-injection high-performance liquid chromatographic (HPLC) method has been developed to monitor contamination levels of the herbicide. The method is sensitive (limit of quantitation = 0.33 microgram/L) and is linear to 33.0 micrograms/L (R2 = 0.9995). Direct injection results from 50 field samples compared well (R2 = 0.98) with an HPLC method using solid-phase extraction for concentration and cleanup. The technique is very reproducible (coefficients of variation of 0-8.4% within day and 3.0-13.2% between day) and eliminates loss of analyte because of fewer steps in the procedure. PMID:10589500

  10. Injectable, rapid gelling and highly flexible hydrogel composites as growth factor and cell carriers.

    PubMed

    Wang, Feng; Li, Zhenqing; Khan, Mahmood; Tamama, Kenichi; Kuppusamy, Periannan; Wagner, William R; Sen, Chandan K; Guan, Jianjun

    2010-06-01

    A family of injectable, rapid gelling and highly flexible hydrogel composites capable of releasing insulin-like growth factor (IGF-1) and delivering mesenchymal stromal cell (MSC) were developed. Hydrogel composites were fabricated from Type I collagen, chondroitin sulfate (CS) and a thermosensitive and degradable hydrogel copolymer based on N-isopropylacrylamide, acrylic acid, N-acryloxysuccinimide and a macromer poly(trimethylene carbonate)-hydroxyethyl methacrylate. The hydrogel copolymer was gellable at body temperature before degradation and soluble at body temperature after degradation. Hydrogel composites exhibited LCSTs around room temperature. They could easily be injected through a 26-gauge needle at 4 degrees C, and were capable of gelling within 6s at 37 degrees C to form highly flexible gels with moduli matching those of the rat and human myocardium. The hydrogel composites showed good oxygen permeability; the oxygen pressure within the hydrogel composites was similar to that in the air. The effects of collagen and CS contents on LCST, gelation time, injectability, mechanical properties and degradation properties were investigated. IGF-1 was loaded into the hydrogel composites for enhanced cell survival/growth. The released IGF-1 remained bioactive during a 2-week release period. Small fraction of CS in the hydrogel composites significantly decreased IGF-1 release rate. The release kinetics appeared to be controlled mainly by hydrogel composite water content, degradation and interaction with IGF-1. Human MSC adhesion on the hydrogel composites was comparable to that on the tissue culture plate. MSCs were encapsulated in the hydrogel composites and were found to grow inside during a 7-day culture period. IGF-1 loading significantly accelerated MSC growth. RT-PCR analysis demonstrated that MSCs maintained their multipotent differentiation potential in hydrogel composites with and without IGF-1. These injectable and rapid gelling hydrogel composites

  11. Achieving a long-lived high-beta plasma state by energetic beam injection.

    PubMed

    Guo, H Y; Binderbauer, M W; Tajima, T; Milroy, R D; Steinhauer, L C; Yang, X; Garate, E G; Gota, H; Korepanov, S; Necas, A; Roche, T; Smirnov, A; Trask, E

    2015-01-01

    Developing a stable plasma state with high-beta (ratio of plasma to magnetic pressures) is of critical importance for an economic magnetic fusion reactor. At the forefront of this endeavour is the field-reversed configuration. Here we demonstrate the kinetic stabilizing effect of fast ions on a disruptive magneto-hydrodynamic instability, known as a tilt mode, which poses a central obstacle to further field-reversed configuration development, by energetic beam injection. This technique, combined with the synergistic effect of active plasma boundary control, enables a fully stable ultra-high-beta (approaching 100%) plasma with a long lifetime. PMID:25902924

  12. Search for auroral belt E-parallel fields with high-velocity barium ion injections

    NASA Technical Reports Server (NTRS)

    Heppner, J. P.; Ledley, B. G.; Miller, M. L.; Marionni, P. A.; Pongratz, M. B.

    1989-01-01

    In April 1984, four high-velocity shaped-charge Ba(+) injections were conducted from two sounding rockets at 770-975 km over northern Alaska under conditions of active auroral and magnetic disturbance. Spatial ionization (brightness) profiles of high-velocity Ba(+) clouds from photometric scans following each release were found to be consistent with the 28-sec theoretical time constant for Ba photoionization determined by Carlsten (1975). These observations therefore revealed no evidence of anomalous fast ionization predicted by the Alfven critical velocity hypothesis.

  13. Achievement of Runaway Electron Energy Dissipation by High-Z Gas Injection in DIII-D

    NASA Astrophysics Data System (ADS)

    Hollmann, E. M.

    2014-10-01

    Disruption runaway electron (RE) formation followed by RE beam-wall strikes is a concern for future tokamaks, motivating the study of mitigation techniques to reduce the RE beam energy in a controlled manner. A promising approach for doing this is the injection of high-Z gas into the RE beam. Massive (100 torr-l) injection of high-Z gas into RE beams in DIII-D is shown to significantly dissipate both RE magnetic and kinetic energy. For example, injection of argon into a typical 300 kA current RE beam is observed to cause a drop in kinetic energy from 50 kJ to 10 kJ in 10 ms, thus rapidly reducing the damage-causing capability of the RE beam. Both the RE kinetic energy and pitch angle are important for determining the resulting wall damage, with high energy, high pitch angle electrons typically considered most dangerous. The RE energy distribution is found to be more skewed toward low energies than predicted by avalanche theory. The pitch angle is not found to be constant, as is frequently assumed, but is shown to drop from sin(θ) ~ 1 for energies less than 1 MeV to sin(θ) ~ 0 . 2 for energies greater than 10 MeV. Injection of high-Z impurities does not appear to change the overall shape of the energy or pitch angle distributions dramatically. The enhanced RE energy dissipation appears to be caused primarily via collisions with the cold plasma leading to line radiation. Synchrotron power loss only becomes significant in the absence of high-Z impurities, while radial transport loss of REs is seen to become dominant if the RE beam moves sufficiently close to the vessel walls. The experiments demonstrate that avalanche theory somewhat underestimates collisional dissipation of REs in the presence of high-Z atoms, even in the absence of radial transport losses, meaning that reducing RE wall damage in large tokamaks should be easier than previously expected. Supported by the US Department of Energy under DE-FG02-07ER54917 and DE-FC02-04ER54698.

  14. Longitudinal mode selection by injection in a high pressure CO/sub 2/ laser

    SciTech Connect

    Angelie, C.; Capitini, R.; Girard, P.

    1987-03-15

    Single longitudinal mode (SLM) selection in a 10-atm CO/sub 2/ laser is reported. Experiments have been performed with cw injection of 1 mW/cm/sup 2/ or pulsed injection of 1 mJ/cm/sup 2/ (in 50 ns) around CO/sub 2/ line centers. A simple analytical formula of the minimum intensity required for injection of a frequency ..nu.. has been obtained. It gives the dependence vs the two most important parameters: (1) the detuning ..nu..-nu-bar to the center nu-bar of the net gain curve, (2) the detuning delta..nu../sub K/ to the nearest longitudinal mode of the cavity. The comparison with experimental results published on TEA lasers is very successful. The application of the formula shows the possibility of SLM selection continuously tunable in a high pressure CO/sub 2/ laser with <1 mW/cm/sup 2/ if a grating is incorporated in the cavity, and with a pulsed source of 1 kW/cm/sup 2/ without any selective element. The actual sources suitable for this purpose are reviewed.

  15. Effect of pressure on viscosity at high shear rates by using an injection molding machine

    NASA Astrophysics Data System (ADS)

    Volpe, Valentina; Pantani, Roberto

    2015-12-01

    The difficulties in performing accurate measurements of the effect of pressure on the viscosity of the polymeric materials results in a shortage of relevant experimental data in the literature. In this work, an atactic polystyrene has been characterized to determine the effect of pressure on viscosity during the injection molding process. In particular, the nozzle of the injection molding machine has been modified to host a slit rheometer that allows obtaining in-line rheological measurements by means of two pressure transducers. Slits with two different geometries have been adopted, in order to obtain a wide range of shear rates (102-105 s-1). Experiments have been conducted at increasing injection flow rates, corresponding to different shear rates. By analyzing the measured pressures it has been possible to determine the coefficient β, which describes the effect of pressure on viscosity. Results show that the effect of pressure on viscosity decreases on increasing the shear rate until a plateau is reached at very high shear rates.

  16. High volume image guided injections and structured rehabilitation in shoulder impingement syndrome: a retrospective study

    PubMed Central

    Morton, Sarah; Chan, Otto; Ghozlan, Asser; Price, Jessica; Perry, John; Morrissey, Dylan

    2015-01-01

    Summary Background the aim was to establish the effect of a high volume-image guided injection and structured rehabilitation (HVIGI&SR) on both pain and function in shoulder impingement syndrome (SIS). Methods 44 participants treated between January 2008 and January 2012 with a >3 month history of recalcitrant ultrasound-confirmed SIS were sent a retrospective questionnaire. All participants had received a HVIGI under ultrasound-guidance consisting of 20 mls of Marcaine with 50 mg of hydrocortisone, followed by a period of physiotherapist-led rehabilitation. The validated Shoulder Pain and Disability Index (SPADI) score was used to establish the change in the score between 1 week pre-injection and 3 weeks post-injection, along with an 11-point pain scale. Results 59% of participants responded. There was a clinically and statistically significant decrease in the SPADI score of 58.7 ± 29.9 (p<0.01). 76% of participants had an improvement in their score of over 50% from their initial score. There was a clinically and statistically significant improvement in pain of 5.19 ± 2.62 (p<0.01) on the numerical rating scale of pain. Conclusion HVIGI&SR should be considered for short-term treatment of SIS as it showed a significant improvement in both pain and function. A prolonged period of physiotherapist-led rehabilitation can then be undertaken for long term benefits. PMID:26605194

  17. ‘It’s more about the heroin’: Injection drug users’ response to an overdose warning campaign in a Canadian setting

    PubMed Central

    Kerr, Thomas; Small, Will; Hyshka, Elaine; Maher, Lisa; Shannon, Kate

    2014-01-01

    Aims To assess heroin injectors’ perceptions of and responses to a warning issued by public health officials regarding high-potency heroin and increases in fatal overdoses. Design Semi-structured qualitative interviews Setting Vancouver, Canada. Participants Eighteen active heroin injectors Measurements Semi-structured interview guide focussing on heroin injectors’ perceptions of and responses to the overdose warning, including reasons for failing to adhere to risk reduction recommendations. Findings Although nearly all participants were aware of the warning, their recollections of the message and the timing of its release were obscured by on-going social interactions within the drug scene focussed on heroin quality. Many injection drug users reported seeking the high potency heroin and nearly all reported no change in overdose risk behaviours. Responses to the warning were shaped by various social, economic and structural forces that interacted with individual behaviour and undermined efforts to promote behavioural change, including sales tactics employed by dealers, poverty, the high cost and shifting quality of available heroin, and risks associated with income-generating activities. Individual-level factors, including emotional suffering, withdrawal, entrenched injecting routines, perceived invincibility and the desire for intense intoxication also undermined risk reduction messages. Conclusions Among heroin injectors in British Columbia, a 2011 overdose warning campaign appeared to be of limited effectiveness and also produced unintended negative consequences that exacerbated overdose risk. PMID:23551565

  18. High dead-space syringe use among people who inject drugs in Tijuana, Mexico

    PubMed Central

    Rafful, Claudia; Zule, William; González-Zúñiga, Patricia E.; Werb, Dan; Elena Medina-Mora, María; Magis-Rodriguez, Carlos; Strathdee, Steffanie A.

    2015-01-01

    Background High dead-space syringes (HDSS) are believed to confer an elevated risk of acquiring HIV and other blood-borne infections. Objectives We identified prevalence and correlates of HDSS use among injection drug users (IDU) in Tijuana, Mexico, where syringe purchase and possession is legal without a prescription. Methods Beginning in 2011, IDU who reported being 18 years or older, who injected drugs within the last month were recruited into a prospective study. At baseline and semi-annually, 557 IDU underwent HIV-testing and interviewer-administered surveys. Logistic regression was used to identify correlates of using HDSS. Results Of 557 IDU, 40% had ever used HDSS, mostly because no other syringe type was available (72%), or because they were easier to get (20%). Controlling for sex and age at first injection, use of HDSS was associated with cocaine as the first drug injected (Adjusted Odds Ratio [AOR]:2.68; Confidence Interval 95% [CI]:1.15-6.22), having been stopped or arrested by police (AOR:1.84; 95% CI:1.11-3.07), being deported from the US (AOR:1.64; 95%CI:1.06-2.53), and believing it is illegal to carry syringes (AOR:1.78; 95%CI:1.01-3.15). Conclusion Use of HDSS is surprisingly common among IDU in Tijuana. Efforts are needed to expand coverage of low-dead space syringes through existing syringe exchange programs. Education is required to increase awareness of the harms associated with HDSS, and to inform IDU that syringe possession is legal across Mexico. PMID:25695145

  19. High pressure jet injection of viscous solutions for endoscopic submucosal dissection (ESD): first clinical experience

    PubMed Central

    Pioche, Mathieu; Lépilliez, Vincent; Déprez, Pierre; Giovannini, Marc; Caillol, Fabrice; Piessevaux, Hubert; Rivory, Jérôme; Guillaud, Olivier; Ciocîrlan, Mihai; Salmon, Damien; Lienhart, Isabelle; Lafon, Cyril; Saurin, Jean-Christophe; Ponchon, Thierry

    2015-01-01

    Background: Long lasting elevation is a key factor during endoscopic submucosal dissection (ESD) and can be obtained by water jet injection of saline solution or by viscous macromolecular solutions. In a previous animal study, we assessed the Nestis Enki II system to combine jet injection and viscous solutions. In the present work, we used this combination in humans in different sites of the digestive tract. Methods: We retrospectively report all of the consecutive ESD procedures performed with jet injection of viscous solutions in four centers. Information was collected about the lesion, the procedure, the histological result, and the outcomes for the patient. Results: In total, 45 resections were completed by six operators: five experts and one beginner with only one previous experience in human ESD. Lesions were located in the esophagus (10), the stomach (11), the duodenum (1), the colon (1) and the rectum (22). Average maximal lesion diameter was 4.8 cm (SD 2.4, range 2 – 11 cm), average lesion surface area was 19.8 cm2 (SD 17.7, range 2.2 – 72 cm2), and average duration of procedure was 79.9 min (SD 50.3 min, range 19 – 225 min). ESD could be conducted while the endoscope was retroflexed at its maximum in 26 cases. Four adverse events were observed: two diminutive perforations and two delayed bleeding occurrences treated conservatively. The R0 resection rate was 91.1 %. The catheter was obstructed in six occurrences of bleeding. Conclusion: Endoscopic submucosal dissection using high pressure injection of viscous macromolecular solutions is safe and effective in different parts of the digestive tract. It does not impede working with the endoscope in the maximal retroflexed position. PMID:26356488

  20. Median Nerve Injury Due to High-Pressure Water Jet Injection: A Case Report and Review of Literature.

    PubMed

    Emre, Ufuk; Unal, Aysun

    2009-08-01

    High-pressure injuries that occur accidentally are potentially destructive injuries that often affect the nondominant hands of young men. A variety of products such as paint, gasoline, grease, fuel oil, cement, thinner and solvents have been reported as destructive agents. High-pressure water jet injection injuries to soft tissues have rarely been reported. In this study, we present the first case of median nerve injury due to high-pressure water jet injection by a water spray gun. PMID:26815059

  1. The Adrenocortical Response of Greater Sage Grouse (Centrocercus urophasianus) to Capture, ACTH Injection, and Confinement, as Measured in Fecal Samples

    PubMed Central

    Jankowski, M. D.; Wittwer, D. J.; Heisey, D. M.; Franson, J. C.; Hofmeister, E. K.

    2009-01-01

    Investigators of wildlife populations often utilize demographic indicators to understand the relationship between habitat characteristics and population viability. Assessments of corticosterone may enable earlier detection of populations at risk of decline because physiological adjustments to habitat disturbance occur before reproductive diminutions. Noninvasive methods to accomplish these assesments are important in species of concern, such as the greater sage grouse (GRSG). Therefore, we validated a radioimmunoassay that measures immunoreactive corticosterone metabolites (ICM) in fecal samples and used it to characterize the adrenocortical response of 15 GRSG exposed to capture, intravenous injection of 50 IU/kg adrenocorticotrophic hormone (ACTH) or saline, and 22 h of confinement. Those animals injected with ACTH exhibited a more sustained (P = 0.0139) and less variable (P = 0.0012) response than those injected with saline, indicating different levels of adrenocortical activity. We also found that potential field-collection protocols of fecal samples did not alter ICM concentrations: samples held at 4°C for up to 16 h contained similar levels of ICM as those frozen (−20°C) immediately. This study demonstrates a multiphasic adrenocortical response that varied with the level of stimulation and indicates that the assay used to measure this phenomenon is applicable for studies of wild GRSG. PMID:19199814

  2. The adrenocortical response of greater sage grouse (Centrocercus urophasianus) to capture, ACTH injection, and confinement, as measured in fecal samples

    USGS Publications Warehouse

    Jankowski, M.D.; Wittwer, D.J.; Heisey, D.M.; Franson, J.C.; Hofmeister, E.K.

    2009-01-01

    Investigators of wildlife populations often utilize demographic indicators to understand the relationship between habitat characteristics and population viability. Assessments of corticosterone may enable earlier detection of populations at risk of decline because physiological adjustments to habitat disturbance occur before reproductive diminutions. Noninvasive methods to accomplish these assesments are important in species of concern, such as the greater sage grouse (GRSG). Therefore, we validated a radioimmunoassay that measures immunoreactive corticosterone metabolites (ICM) in fecal samples and used it to characterize the adrenocortical response of 15 GRSG exposed to capture, intravenous injection of 50 IU/kg adrenocorticotrophic hormone (ACTH) or saline, and 22 h of confinement. Those animals injected with ACTH exhibited a more sustained (P = 0.0139) and less variable (P = 0.0012) response than those injected with saline, indicating different levels of adrenocortical activity. We also found that potential field-collection protocols of fecal samples did not alter ICM concentrations: samples held at 4??C for up to 16 h contained similar levels of ICM as those frozen (-20??C) immediately. This study demonstrates a multiphasic adrenocortical response that varied with the level of stimulation and indicates that the assay used to measure this phenomenon is applicable for studies of wild GRSG. ?? 2009 by The University of Chicago. All rights reserved.

  3. The adrenocortical response of greater sage grouse (Centrocercus urophasianus) to capture, ACTH injection, and confinement, as measured in fecal samples.

    PubMed

    Jankowski, M D; Wittwer, D J; Heisey, D M; Franson, J C; Hofmeister, E K

    2009-01-01

    Investigators of wildlife populations often utilize demographic indicators to understand the relationship between habitat characteristics and population viability. Assessments of corticosterone may enable earlier detection of populations at risk of decline because physiological adjustments to habitat disturbance occur before reproductive diminutions. Noninvasive methods to accomplish these assessments are important in species of concern, such as the greater sage grouse (GRSG). Therefore, we validated a radioimmunoassay that measures immunoreactive corticosterone metabolites (ICM) in fecal samples and used it to characterize the adrenocortical response of 15 GRSG exposed to capture, intravenous injection of 50 IU/kg adrenocorticotrophic hormone (ACTH) or saline, and 22 h of confinement. Those animals injected with ACTH exhibited a more sustained (P = 0.0139) and less variable (P = 0.0012) response than those injected with saline, indicating different levels of adrenocortical activity. We also found that potential field-collection protocols of fecal samples did not alter ICM concentrations: samples held at 4 degrees C for up to 16 h contained similar levels of ICM as those frozen (-20 degrees C) immediately. This study demonstrates a multiphasic adrenocortical response that varied with the level of stimulation and indicates that the assay used to measure this phenomenon is applicable for studies of wild GRSG. PMID:19199814

  4. Natural killer cells in highly exposed hepatitis C-seronegative injecting drug users.

    PubMed

    Mina, M M; Cameron, B; Luciani, F; Vollmer-Conna, U; Lloyd, A R

    2016-06-01

    Injecting drug use remains the major risk factor for hepatitis C (HCV) transmission. A minority of long-term injecting drug users remain seronegative and aviraemic, despite prolonged exposure to HCV - termed highly exposed seronegative subjects. Natural killer (NK) cells have been implicated in this apparent protection. A longitudinal nested, three group case-control series of subjects was selected from a prospective cohort of seronegative injecting drug users who became incident cases (n = 11), remained seronegative (n = 11) or reported transient high-risk behaviour and remained uninfected (n = 11). The groups were matched by age, sex and initial risk behaviour characteristics. Stored peripheral blood mononuclear cells were assayed in multicolour flow cytometry to enumerate natural killer cell subpopulations and to assess functional activity using Toll-like receptor ligands before measurement of activation, cytokine production and natural cytotoxicity receptor expression. Principal components were derived to describe the detailed phenotypic characteristics of the major NK subpopulations (based on CD56 and CD16 co-expression), before logistic regression analysis to identify associations with exposed, seronegative individuals. The CD56(dim) CD16(+) (P = 0.05, OR 6.92) and CD56(dim) CD16(-) (P = 0.05, OR 6.07) principal components differed between exposed, seronegative individuals and pre-infection samples of the other two groups. These included CD56(dim) CD16(+) and CD56(dim) CD16(-) subsets with CD56(dim) CD16(+) IFN-γ and TNF-α on unstimulated cells, and CD56(dim) CD16(-) CD69(+) , CD107a(+) , IFN-γ and TNF-α following TLR stimulation. The cytotoxic CD56(dim) NK subset thus distinguished highly exposed, seronegative subjects, suggesting NK cytotoxicity may contribute to protection from HCV acquisition. Further investigation of the determinants of this association and prospective assessment of protection against HCV infection are warranted. PMID:26833632

  5. Thermal Control Method for High-Current Wire Bundles by Injecting a Thermally Conductive Filler

    NASA Technical Reports Server (NTRS)

    Rodriguez-Ruiz, Juan; Rowles, Russell; Greer, Greg

    2011-01-01

    A procedure was developed to inject thermal filler material (a paste-like substance) inside the power wire bundle coming from solar arrays. This substance fills in voids between wires, which enhances the heat path and reduces wire temperature. This leads to a reduced amount of heat generated. This technique is especially helpful for current and future generation high-power spacecraft (1 kW or more), because the heat generated by the power wires is significant enough to cause unacceptable overheating to critical components that are in close contact with the bundle.

  6. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor refueling

    SciTech Connect

    Kim, K.; Honig, J.

    1984-09-01

    Design, construction, testing, and performance evaluation of a small-bore plasma-arc-driven electromagnetic railgun system are described. The railgun system, which is intended for injecting high-velocity hydrogen pellets into the magnetic fusion devices for the purpose of refueling, has two acceleration stages. One consists of a gas gun preaccelerator and the other a railgun booster accelerator. The plasma-arc armature is formed behind the pellet by electrically discharging the propellant gas following the pellet into the railgun from the gas gun.

  7. Stability analysis and testing of a train of centrifugal compressors for high pressure gas injection

    SciTech Connect

    Memmott, E.A.

    1999-07-01

    This paper describes the rotor dynamic stability analysis and the PTC-10 Class 1 test of a three body centrifugal compressor train for high pressure natural gas injection services. This train had a full load full pressure string test on hydrocarbon gases to a final discharge pressure of 500 BAR (7250 PSIA). Each compressor is of the back to back configuration, and is equipped with tilting pad seals, damper bearings, and a honeycomb labyrinth at the division wall with shunt holes. The driver is a gas turbine.

  8. Kinoform/lens system for injecting a high power laser beam into an optical fiber

    SciTech Connect

    Sweatt, W.C.; Farn, M.W.

    1993-11-01

    A method for injecting a high peak power multimode YAG laser beam into an optical fiber has been developed. The design minimizes the peak irradiance on the fiber`s entrance face and reduces its dependence on the laser`s mode structure and the system alignment. A simple lens and a specially designed kinoform (or binary optics element) operate together to transform a 5 mm diameter laser beam into two concentric ring foci that fit on the 400 {mu}m diameter fiber face.

  9. Sub-Poissonian shot noise of a high internal gain injection photon detector.

    PubMed

    Memis, Omer Gokalp; Katsnelson, Alex; Kong, Soon-Cheol; Mohseni, Hooman; Yan, Minjun; Zhang, Shuang; Hossain, Tim; Jin, Niu; Adesida, Ilesanmi

    2008-08-18

    The noise performance of an infrared injection photon detector with very high internal gain was investigated at a wavelength of 1.55 mum. The devices showed sub-Poissonian shot noise with Fano factors around 0.55 at 0.7 V at room temperature. Optical to electrical conversion factors of 3000 electrons per absorbed photon were recorded at 0.7 V. The change in noise-equivalent power with respect to bias voltage was evaluated. The optical to electrical conversion factor and Fano factor were measured under increasing illumination and compared to theoretical expectations. PMID:18711508

  10. Real-time tracking of CO₂ injected into a subsurface coal fire through high-frequency measurements of the ¹³CO₂ signature.

    PubMed

    Krevor, Samuel C M; Ide, Taku; Benson, Sally M; Orr, Franklin M

    2011-05-01

    CO₂ was injected into a coal fire burning at a depth of 15 m in the subsurface in southwestern Colorado, USA. Measurements were made of the ¹³CO₂ isotopic signature of gas exhaust from an observation well and two surface fissures. The goal of the test was to determine (1) whether CO₂ with a distinct isotopic signature could be used as a tracer to identify flow pathways and travel times in a combustion setting where CO₂ was present in significant quantities in the gases being emitted from the coalbed fire, and (2) to confirm the existence of a self-propagating system of air-intake and combustion gas exhaust that has been previously proposed. CO₂ was injected in three separate periods. The ¹³CO₂ isotopic signature was measured at high frequency (0.5 Hz) before, during, and after the injection periods for gas flowing from fissures over the fire and from gas entering an observation well drilled into the formation just above the fire but near the combustion zone. In two cases, a shift in the isotopic signature of outgassing CO₂ provided clear evidence that injected CO₂ had traveled from the injection well to the observation point, while in a third case, no response was seen and the fissure could not be assumed to have a flowpath connected with the injection well. High-frequency measurements of the ¹³CO₂ signature of gas in observation wells is identified as a viable technique for tracking CO₂ injected into subsurface formations in real-time. In addition, a chimney-like coupled air-intake and exhaust outlet system feeding the combustion of the coal seam was confirmed. This can be used to further develop strategies for extinguishing the fire. PMID:21466184

  11. High Speed Si Etching with ClF{sub 3} Cluster Injection

    SciTech Connect

    Seki, T.; Yoshino, Y.; Senoo, T.; Koike, K.; Ninomiya, S.; Matsuo, J.; Aoki, T.

    2011-01-07

    The reactive gas cluster injection process is an etching method that uses a neutral cluster beam without plasma. ClF{sub 3}-Ar neutral cluster was generated and the Si etching characteristics with this beam were investigated. ClF{sub 3} is very high reactive gas. Adiabatic expansion of a high-pressure gas through a conical nozzle is utilized for the formation of cluster beams. The source gas was a mixture of ClF{sub 3}(6%) with Ar (94%). The etching rate increased with source gas pressure nonlinearly, and the etching rate achieved more than 30 {mu}m/min at 0.85 MPa. Although the irradiation energy was very low (<1 eV/atom or molecule), the chemical etching was enhanced with cluster impacts and the cluster bombarded area on the surface was etched selectively. These results indicated that high speed anisotropic etching with low damage can be realized with the ClF{sub 3} cluster injection process.

  12. Instability Analysis of a Low-Density Gas Jet Injected into a High-Density Gas

    NASA Technical Reports Server (NTRS)

    Lawson, Anthony Layiwola

    2001-01-01

    The objective of this study was to determine the effects of buoyancy on the absolute instability of low-density gas jets injected into high-density gas mediums. Most of the existing analyses of low-density gas jets injected into a high-density ambient have been carried out neglecting effects of gravity. In order to investigate the influence of gravity on the near-injector development of the flow, a linear temporal stability analysis and a spatio-temporal stability analysis of a low-density round jet injected into a high-density ambient gas were performed. The flow was assumed to be isothermal and locally parallel; viscous and diffusive effects were ignored. The variables were represented as the sum of the mean value and a normal-mode small disturbance. An ordinary differential equation governing the amplitude of the pressure disturbance was derived. The velocity and density profiles in the shear layer, and the Froude number (signifying the effects of gravity) were the three important parameters in this equation. Together with the boundary conditions, an eigenvalue problem was formulated. Assuming that the velocity and density profiles in the shear layer to be represented by hyperbolic tangent functions, the eigenvalue problem was solved for various values of Froude number. The temporal growth rates and the phase velocity of the disturbances were obtained. It was found that the presence of variable density within the shear layer resulted in an increase in the temporal amplification rate of the disturbances and an increase in the range of unstable frequencies, accompanied by a reduction in the phase velocities of the disturbances. Also, the temporal growth rates of the disturbances were increased as the Froude number was reduced (i.e. gravitational effects increased), indicating the destabilizing role played by gravity. The spatio-temporal stability analysis was performed to determine the nature of the absolute instability of the jet. The roles of the density ratio

  13. Host responses in human skin after conventional intradermal injection or microneedle administration of virus-like-particle influenza vaccine

    PubMed Central

    Pearton, Marc; Pirri, Daniela; Kang, Sang-Moo; Compans, Richard W; Birchall, James C

    2014-01-01

    Miniaturized microneedle devices are being developed for painlessly targeting vaccines to the immune cell populations in skin. As skin immunization studies are generally restricted to animal models however, where skin architecture and immunity is greatly different to human, surprisingly little is known about the local human response to intradermal (ID) vaccines. Here we use surgically excised human skin to explore for the first time the complex molecular and cellular host responses to a candidate influenza vaccine comprising nanoparticulate virus-like-particles (VLPs), administered via conventional hypodermic injection or reduced scale microneedles. Responses at the molecular level are determined by microarray analysis (47,296 discrete transcripts) and validated by quantitative PCR (96 genes). Cellular response is probed through monitoring migration of dendritic cells in viable skin tissue. Gene expression mapping, ontological analysis and qPCR reveal up-regulation of a host of genes responsible for key immunomodulatory processes and host viral response, including cell recruitment, activation, migration and T cell interaction following both ID and microneedle injection of VLPs; the response from the microneedles being more subtle. Significant morphological and migratory changes to skin dendritic cells are also apparent following microneedle VLP delivery. This is the first study displaying the global, multifaceted immunological events that occur at the site of vaccine deposition in human skin and will subsequently influence the degree and nature of innate and adaptive immune responses. An increased understanding of the detailed similarities and differences in response against antigen administered via different delivery modalities will inform the development of improved vaccines and vaccine delivery systems. PMID:23564440

  14. TLR9 and IRF3 Cooperate to Induce a Systemic Inflammatory Response in Mice Injected With Liposome:DNA

    PubMed Central

    Walker, Wendy E; Booth, Carmen J; Goldstein, Daniel R

    2010-01-01

    Liposome:DNA is a promising gene therapy vector. However, this vector can elicit a systemic inflammatory response syndrome (SIRS). Prior reports indicate that liposome:DNA vectors activate Toll-like receptor (TLR)9. We hypothesized that liposome:DNA vectors also activate the cytosolic DNA-sensing pathway, which signals via interferon (IFN) regulatory factor (IRF)3. To test this, we treated dendritic cells (DCs) with liposome:DNA in vitro and found that IRF3 was phosphorylated independent of TLR9. To test the contribution of this pathway in vivo, we injected a liposome:DNA vector into wild-type (WT), TLR9-knockout (KO), IRF3-KO, and TLR9-IRF3-double-KO (DKO) mice. WT mice exhibited a systemic inflammatory response, evidenced by elevations in serum cytokines, serum enzyme changes indicating organ damage, hypothermia, and mortality. The cytokine response was reduced in TLR9-KO, IRF3-KO, and TLR9-IRF3-DKO mice and all three groups survived. We found that IFN-γ-KO mice that receive liposome:DNA had a reduced cytokine response and 100% survival. CD11c+ and NK1.1+ cells produced IFN-γ and depleting CD11c+ cells reduced the cytokine response in mice injected with liposome:DNA. These findings may facilitate the development of immunologically inert gene therapy vectors and may provide general insight into the mechanisms of SIRS. PMID:20145605

  15. A Study of Micro Injection Molding for High-Aspect-Ratio Optical Fiber Ferrules

    NASA Astrophysics Data System (ADS)

    Lin, Zheng-Guan.; Tseng, Shi-Chang; Wang, James; Su, Yi-Chung

    2004-06-01

    This study focused on manufacture of high-aspect-ratio optical fiber ferrules by micro thermoplastic injection molding technique. In the past, the optical fiber connectors were produced by ceramic powder injection molding and subsequent precision grinding process. In this work, plastic micro injection molding technique was attempted to manufacture net-shaped products at once. Each ferrule has a micro through hole in the center. The hole's diameter is 125±1μm, and its length is 9mm. During micro molding, how to keep the micro core pin at the center becomes a critical issue. In this work, a guiding slide system is introduced to hold the micro pin continuously. And the slide movement was controlled by a spring behind it. Such a guiding system can help reduce mis-alignment of the micro core pin and increase its life time. Taguchi's design of experiment was used to evaluate the effects of processing parameters on final properties. Experimental results reveal that the higher the spring force, the larger the product weight and the lower the shrinkage. In order to obtain better uniformity of diameters at different locations, diameters at three locations were measured. Measured data showed the shrinkage of diameter in the middle is greater than those at two ends. It is because the two ends cooled faster than the center region. This can be improved by applying higher mold temperature or appropriate holding pressure or holding time. The new design concept can be applied in molding micro tubes, especially for the high aspect ratio cases.

  16. Injectable hydrogels with high fixed charge density and swelling pressure for nucleus pulposus repair: biomimetic glycosaminoglycan analogues.

    PubMed

    Sivan, S S; Roberts, S; Urban, J P G; Menage, J; Bramhill, J; Campbell, D; Franklin, V J; Lydon, F; Merkher, Y; Maroudas, A; Tighe, B J

    2014-03-01

    The load-bearing biomechanical role of the intervertebral disc is governed by the composition and organization of its major macromolecular components, collagen and aggrecan. The major function of aggrecan is to maintain tissue hydration, and hence disc height, under the high loads imposed by muscle activity and body weight. Key to this role is the high negative fixed charge of its glycosaminoglycan side chains, which impart a high osmotic pressure to the tissue, thus regulating and maintaining tissue hydration and hence disc height under load. In degenerate discs, aggrecan degrades and is lost from the disc, particularly centrally from the nucleus pulposus. This loss of fixed charge results in reduced hydration and loss of disc height; such changes are closely associated with low back pain. The present authors developed biomimetic glycosaminoglycan analogues based on sulphonate-containing polymers. These biomimetics are deliverable via injection into the disc where they polymerize in situ, forming a non-degradable, nuclear "implant" aimed at restoring disc height to degenerate discs, thereby relieving back pain. In vitro, these glycosaminoglycan analogues possess appropriate fixed charge density, hydration and osmotic responsiveness, thereby displaying the capacity to restore disc height and function. Preliminary biomechanical tests using a degenerate explant model showed that the implant adapts to the space into which it is injected and restores stiffness. These hydrogels mimic the role taken by glycosaminoglycans in vivo and, unlike other hydrogels, provide an intrinsic swelling pressure, which can maintain disc hydration and height under the high and variable compressive loads encountered in vivo. PMID:24270091

  17. Wall-slip of highly filled powder injection molding compounds: Effect of flow channel geometry and roughness

    SciTech Connect

    Hausnerova, Berenika; Sanetrnik, Daniel; Paravanova, Gordana

    2014-05-15

    The paper deals with the rheological behavior of highly filled compounds proceeded via powder injection molding (PIM) and applied in many sectors of industry (automotive, medicine, electronic or military). Online rheometer equipped with slit dies varying in surface roughness and dimensions was applied to investigate the wall-slip as a rheological phenomenon, which can be considered as a parameter indicating the separation of compound components (polymer binder and metallic powder) during high shear rates when injection molded.

  18. Wall-slip of highly filled powder injection molding compounds: Effect of flow channel geometry and roughness

    NASA Astrophysics Data System (ADS)

    Hausnerova, Berenika; Sanetrnik, Daniel; Paravanova, Gordana

    2014-05-01

    The paper deals with the rheological behavior of highly filled compounds proceeded via powder injection molding (PIM) and applied in many sectors of industry (automotive, medicine, electronic or military). Online rheometer equipped with slit dies varying in surface roughness and dimensions was applied to investigate the wall-slip as a rheological phenomenon, which can be considered as a parameter indicating the separation of compound components (polymer binder and metallic powder) during high shear rates when injection molded.

  19. CCK-8 injected into the nucleus accumbens attenuates the supersensitive locomotor response to apomorphine in 6-OHDA and chronic-neuroleptic treated rats.

    PubMed

    Weiss, F; Ettenberg, A; Koob, G F

    1989-01-01

    Postsynaptic dopamine-cholecystokinin (CCK) interactions in the nucleus accumbens were studied in two behavioral preparations of DA receptor supersensitivity: chronic-neuroleptic treated and 6-hydroxydopamine (6-OHDA) denervated rats. Subcutaneous (SC) injections of apomorphine (APO; 0.15 mg/kg) in experiment 1 produced marked hyperlocomotion in rats following 12 days of pretreatment with cis-[Z]-flupenthixol (2 mg/kg; twice per day). Bilateral intra-accumbens (N.Acc.) microinjections of CCK-8 (2 ng and 2 micrograms) reliably reduced APO-stimulated hyperlocomotion. An intermediate CCK dose (20 ng) was without effect. No change in APO responsivity following chronic vehicle treatment was observed and the baseline APO response was not altered by CCK at any dose. Denervation of mesolimbic dopamine (DA) terminals by intra-N.Acc. injections of 6-hydroxydopamine (6-OHDA; 8 micrograms/side) in experiment 2 similarly resulted in intense locomotor hyperactivity after APO stimulation (0.1 mg/kg; SC). Bilateral intra-N.Acc. injections of CCK-8 (1, 10, 100 ng, and 1 micrograms) significantly attenuated the supersensitive locomotor response to APO. As in experiment 1, CCK produced "biphasic" dose-response effects with strong attenuation that persisted throughout the entire 60-min test at both high (1 microgram) and low (1 ng) doses. Intermediate CCK doses (10 and 100 ng) produced only short-term reductions in activity. Hypomotility induced by APO in SHAM-lesioned rats was not effectively reversed by CCK treatments. CCK had no effect on unstimulated baseline locomotor activity in either 6-OHDA or SHAM-lesioned rats. These results provide further evidence that CCK-8 modulates mesolimbic DA activity by functionally opposing the postsynaptic effects of DA in the region of the nucleus accumbens. PMID:2574480

  20. High-Dose Vincristine Sulfate Liposome Injection for Advanced, Relapsed, and Refractory Adult Philadelphia Chromosome–Negative Acute Lymphoblastic Leukemia

    PubMed Central

    O'Brien, Susan; Schiller, Gary; Lister, John; Damon, Lloyd; Goldberg, Stuart; Aulitzky, Walter; Ben-Yehuda, Dina; Stock, Wendy; Coutre, Steven; Douer, Dan; Heffner, Leonard T.; Larson, Melissa; Seiter, Karen; Smith, Scott; Assouline, Sarit; Kuriakose, Philip; Maness, Lori; Nagler, Arnon; Rowe, Jacob; Schaich, Markus; Shpilberg, Ofer; Yee, Karen; Schmieder, Guenter; Silverman, Jeffrey A.; Thomas, Deborah; Deitcher, Steven R.; Kantarjian, Hagop

    2013-01-01

    Purpose Relapsed adult acute lymphoblastic leukemia (ALL) is associated with high reinduction mortality, chemotherapy resistance, and rapid progression leading to death. Vincristine sulfate liposome injection (VSLI), sphingomyelin and cholesterol nanoparticle vincristine (VCR), facilitates VCR dose-intensification and densification plus enhances target tissue delivery. We evaluated high-dose VSLI monotherapy in adults with Philadelphia chromosome (Ph) –negative ALL that was multiply relapsed, relapsed and refractory to reinduction, and/or relapsed after hematopoietic cell transplantation (HCT). Patients and Methods Sixty-five adults with Ph-negative ALL in second or greater relapse or whose disease had progressed following two or more leukemia therapies were treated in this pivotal phase II, multinational trial. Intravenous VSLI 2.25 mg/m2, without dose capping, was administered once per week until response, progression, toxicity, or pursuit of HCT. The primary end point was achievement of complete response (CR) or CR with incomplete hematologic recovery (CRi). Results The CR/CRi rate was 20% and overall response rate was 35%. VSLI monotherapy was effective as third-, fourth-, and fifth-line therapy and in patients refractory to other single- and multiagent reinduction therapies. Median CR/CRi duration was 23 weeks (range, 5 to 66 weeks); 12 patients bridged to a post-VSLI HCT, and five patients were long-term survivors. VSLI was generally well tolerated and associated with a low 30-day mortality rate (12%). Conclusion High-dose VSLI monotherapy resulted in meaningful clinical outcomes including durable responses and bridging to HCT in advanced ALL settings. The toxicity profile of VSLI was predictable, manageable, and comparable to standard VCR despite the delivery of large, normally unachievable, individual and cumulative doses of VCR. PMID:23169518

  1. A low pressure on-chip injection strategy for high-performance chip-based chromatography.

    PubMed

    Thurmann, S; Dittmar, A; Belder, D

    2014-05-01

    A microfluidic device for high-performance liquid chromatography is presented. The borosilicate glass chip includes a common cross-channel injector and a column chamber. The column chamber comprises two constrictions (10 μm) to retain the chromatographic particles via the keystone effect. A packing channel was utilized to introduce the particulate material (3-μm). This channel has been sealed permanently via laser-assisted photopolymerization avoiding dead volumes within the chromatographic pathway. A sampling strategy is presented enabling the directed definition of the sample plug on-chip. The injection process is studied via video microscopy and chromatographic separations of test solutes with fluorescence detection. Our approach, based on on-chip flow splitting, allows the usage of traditional, economic and robust HPLC instrumentation avoiding the need for sophisticated nano-flow equipment. The performance of the chip device and the injection process was demonstrated by reversed-phase chromatographic separations of a mixture of polycyclic aromatic hydrocarbons achieving constant high efficiencies for the chromatographic signals over the whole elution window. PMID:24674642

  2. High numerical aperture injection-molded miniature objective for fiber-optic confocal reflectance microscopy

    NASA Astrophysics Data System (ADS)

    Chidley, Matthew Douglas

    This dissertation presents the design of a miniature injection-molded objective lens for a fiber-optic confocal reflectance microscope. This is part of an effort to demonstrate the ability to fabricate low cost, high performance biomedical optics for high resolution in vivo imaging. Disposable endoscopic microscope objectives could help in vivo confocal microscopy technology mature to enable large-scale clinical screening and detection of early cancers and pre-cancerous lesions. This five lens plastic objective has been tested as a stand-alone optical system and has been coupled to a confocal microscope for in vivo imaging of cells and tissue. Changing the spacing and rotation of the individual optical elements can compensate for fabrication inaccuracies and improve performance. An optical-bench testing system was constructed to allow interactive alignment during testing. The modulation transfer function (MTF) of the miniature objective lens is determined using the slanted-edge method. A custom MATLAB program, edgeMTF, was written to collect, analyze, and record test data. An estimated Strehl ratio of 0.64 and an MTF value of 0.70, at the fiber-optic bundle Nyquist frequency, have been obtained. The main performance limitations of the miniature objective are mechanical alignment and flow-induced birefringence. Annealing and experimental injection molding runs were conducted in effort to reduce birefringence.

  3. High thermal stability fluorene-based hole-injecting material for organic light-emitting devices

    NASA Astrophysics Data System (ADS)

    Li, Lu; Jiao, Bo; Li, Sanfeng; Ma, Lin; Yu, Yue; Wu, Zhaoxin

    2016-03-01

    Novel N1,N3,N5-tris(9,9-diphenyl-9H-fluroen-2-yl)-N1,N3,N5-triphenylbenzene-1,3,5-triamine (TFADB) was synthesized and characterized as a hole-injecting material (HIM) for organic light-emitting devices (OLEDs). By incorporating fluorene group TFADB shows a high glass-transition temperature Tg > 168 °C, indicative of excellent thermal stability. TFADB-based devices exhibited the highest performance in terms of the maximum current efficiency (6.0 cd/A), maximum power efficiency (4.0 lm/W), which is improved than that of the standard device based on 4-4‧-4″Tris(N-(naphthalene-2-yl)-N-phenyl-amino)triphenylamine (2T-NATA) (5.2 cd/A, 3.6 lm/W). This material could be a promising hole-injecting material, especially for the high temperature applications of OLEDs and other organic electronic devices.

  4. An injectable, dual pH and oxidation-responsive supramolecular hydrogel for controlled dual drug delivery.

    PubMed

    Cheng, Xinfeng; Jin, Yong; Sun, Tongbing; Qi, Rui; Li, Hanping; Fan, Wuhou

    2016-05-01

    A novel pH and oxidation dual-responsive and injectable supramolecular hydrogel was developed, which was formed from multi-block copolymer poly(ether urethane) (PEU) and α-cyclodextrin (α-CD) inclusion complexes (ICs). The PEU copolymer was synthesized through a simple one-pot condensation polymerization of poly(ethylene glycol), di(1-hydroxyethylene) diselenide, dimethylolpropionic acid and 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate. In aqueous solution, the amphiphilic PEU copolymers could self-assemble into nanoparticles with dual pH and oxidation sensitivities, which can efficiently load and controllably release a hydrophobic drug indomethacin (IND). Then a dual-drug loaded supramolecular hydrogel was obtained by addition of α-CD and hydrophilic model drug (rhodamine B, RB) into the resulting IND-loaded PEU nanoparticle solution. The rheology studies showed that the supramolecular hydrogels with good injectability underwent a pH-induced reversible sol-gel transition and an oxidation-triggered degradation behavior. The in vitro drug release results demonstrated that the hydrogels showed dual drug release behavior and the release rates could be significantly accelerated by addition of an oxidizing agent (H2O2) or increasing the environmental pH. Therefore, this injectable and dual stimuli-responsive supramolecular hydrogel based codelivery systems could potentially be a promising candidate for controlled drug delivery systems. PMID:26851440

  5. A moderate increase in ambient temperature modulates the Atlantic cod (Gadus morhua) spleen transcriptome response to intraperitoneal viral mimic injection

    PubMed Central

    2012-01-01

    Background Atlantic cod (Gadus morhua) reared in sea-cages can experience large variations in temperature, and these have been shown to affect their immune function. We used the new 20K Atlantic cod microarray to investigate how a water temperature change which, simulates that seen in Newfoundland during the spring-summer (i.e. from 10°C to 16°C, 1°C increase every 5 days) impacted the cod spleen transcriptome response to the intraperitoneal injection of a viral mimic (polyriboinosinic polyribocytidylic acid, pIC). Results The temperature regime alone did not cause any significant increases in plasma cortisol levels and only minor changes in spleen gene transcription. However, it had a considerable impact on the fish spleen transcriptome response to pIC [290 and 339 significantly differentially expressed genes between 16°C and 10°C at 6 and 24 hours post-injection (HPI), respectively]. Seventeen microarray-identified transcripts were selected for QPCR validation based on immune-relevant functional annotations. Fifteen of these transcripts (i.e. 88%), including DHX58, STAT1, IRF7, ISG15, RSAD2 and IκBα, were shown by QPCR to be significantly induced by pIC. Conclusions The temperature increase appeared to accelerate the spleen immune transcriptome response to pIC. We found 41 and 999 genes differentially expressed between fish injected with PBS vs. pIC at 10°C and sampled at 6HPI and 24HPI, respectively. In contrast, there were 656 and 246 genes differentially expressed between fish injected with PBS vs. pIC at 16°C and sampled at 6HPI and 24HPI, respectively. Our results indicate that the modulation of mRNA expression of genes belonging to the NF-κB and type I interferon signal transduction pathways may play a role in controlling temperature-induced changes in the spleen’s transcript expression response to pIC. Moreover, interferon effector genes such as ISG15 and RSAD2 were differentially expressed between fish injected with pIC at 10°C vs. 16

  6. Nitric Oxide and Protein Disulfide Isomerase Explain the Complexities of Unfolded Protein Response Following Intra-hippocampal Aβ Injection.

    PubMed

    Khodagholi, Fariba; Digaleh, Hadi; Motamedi, Fereshteh; Foolad, Forough; Shaerzadeh, Fatemeh

    2016-08-01

    Several pathways involved in regulation of intracellular protein integrity are known as the protein quality control (PQC) system. Molecular chaperones as the main players are engaged in various aspects of PQC system. According to the importance of these proteins in cell survival, in the present study, we traced endoplasmic reticulum-specific markers and chaperone-mediated autophagy (CMA)-associated factors as two main arms of PQC system in intra-hippocampal amyloid beta (Aβ)-injected rats during 10 days running. Data analysis from Western blot indicated that exposure to Aβ activates immunoglobulin heavy-chain-binding protein (Bip) which is the upstream regulator of unfolded protein responses (UPR). Activation of UPR system eventually led to induction of pro-apoptotic factors like CHOP, calpain, and caspase-12. Moreover, our data revealed that protein disulfide isomerase activity dramatically decreased after Aβ injection, which could be attributed to the increased levels of nitric oxide. Besides, Aβ injection induced levels of 2 members of heat shock proteins (Hsp) 70 and 90. Elevated levels of Hsps family members are accompanied by increased levels of lysosome-associated membrane protein type-2A (Lamp-2A) that are involved in CMA. Despite the reduction in CHOP, calpain, caspase-12, and Lamp-2A protein levels, the levels of molecular chaperones Bip, Hsps70, and 90 increased 10 days after Aβ injection in comparison to the control group. Based on our results, 10 days after Aβ injection, despite the activation of protective chaperones, markers associated with neurotoxicity were still elevated. PMID:26391027

  7. Acute inflammatory response of the male breasts secondary to self-injection of petroleum jelly: a case report.

    PubMed

    Chen, Ming; Yalamanchili, Chandana; Hamous, James; Piskun, Mary A; Weis, Brian

    2008-04-01

    The injection of liquid foreign materials such as petroleum jelly and paraffin oil was used as an early medical intervention for the augmentation of body contour in the late 19th century. These practices were associated with severe late onset complications and they have been abandoned by plastic surgeons today. This article discusses a male-to-female transsexual patient with an acute inflammatory response with early sclerosing lipogranuloma of breasts associated with the self-injection of large amounts of petroleum jelly. The inflammation is successfully controlled with the early administration of prophylactic broad-spectrum antibiotics, steroids, and nonsteroid anti-inflammatory agents followed by a subcutaneous mastectomy. The importance of medical education and psychology counseling is discussed. PMID:18360333

  8. Inadvertent high spinal anesthesia as sequelae to epidural injection of normal saline.

    PubMed

    Dhir, Vinod Bala; Sharma, Anupama Gill; Kaur, Mohandeep; Gulabani, Michell

    2015-01-01

    Here we present a case of high spinal blockade in a patient belonging to ASA Grade I which lead to need for endotracheal intubation. A 35 year old healthy male, weighing 59 kg, of height 165 cms presented with a post traumatic raw area over the left lower limb. A reverse sural graft along with skin grafting (from the thigh) was planned. In OR, the patient was placed in sitting position and the extradural space was identified by 'loss of resistance to air' technique at the L2-L3 intervertebral space. The catheter could not be threaded into the extradural space, hence 5ml of 0.9% saline was injected. However, still the catheter could not be negotiated. Further attempts to identify the extradural space at the L1-L2 and L3-L4 interspace levels were made. During these attempts a total of 18 ml of 0.9% saline was injected into the extradural space. Within 2 minutes blood pressure fell to 90/60 mmHg. Injection mephenteramine (3 mg) was given intravenously and a slight head up tilt was applied. After 2 more minutes the patient started complaining of tingling in his hands and difficulty in breathing. Oxygen 100% was administered via a face mask attached to the anesthesia circle system. In view of onset of respiratory failure, general anesthesia was induced. Thiopentone (200 mg) and Suxamethonium (75 mg) were given intravenously, the patient's trachea was intubated and his lungs ventilated with 40% oxygen, 60% nitrous oxide and 0.2-0.4% Isoflurane, without additional neuromuscular blockade. The arterial saturation promptly returned to 97% and, immediately after intubation, the heart rate was found to be 103 beats/min and the arterial BP 162/102 mmHg. At the end of surgery, spontaneous ventilation returned and the patient was allowed to breathe 100% oxygen via the tracheal tube until he awoke, when his trachea was extubated. PMID:25886433

  9. Inadvertent high spinal anesthesia as sequelae to epidural injection of normal saline

    PubMed Central

    Dhir, Vinod Bala; Sharma, Anupama Gill; Kaur, Mohandeep; Gulabani, Michell

    2015-01-01

    Here we present a case of high spinal blockade in a patient belonging to ASA Grade I which lead to need for endotracheal intubation. A 35 year old healthy male, weighing 59 kg, of height 165 cms presented with a post traumatic raw area over the left lower limb. A reverse sural graft along with skin grafting (from the thigh) was planned. In OR, the patient was placed in sitting position and the extradural space was identified by ‘loss of resistance to air’ technique at the L2-L3 intervertebral space. The catheter could not be threaded into the extradural space, hence 5ml of 0.9% saline was injected. However, still the catheter could not be negotiated. Further attempts to identify the extradural space at the L1-L2 and L3-L4 interspace levels were made. During these attempts a total of 18 ml of 0.9% saline was injected into the extradural space. Within 2 minutes blood pressure fell to 90/60 mmHg. Injection mephenteramine (3 mg) was given intravenously and a slight head up tilt was applied. After 2 more minutes the patient started complaining of tingling in his hands and difficulty in breathing. Oxygen 100% was administered via a face mask attached to the anesthesia circle system. In view of onset of respiratory failure, general anesthesia was induced. Thiopentone (200 mg) and Suxamethonium (75 mg) were given intravenously, the patient's trachea was intubated and his lungs ventilated with 40% oxygen, 60% nitrous oxide and 0.2-0.4% Isoflurane, without additional neuromuscular blockade. The arterial saturation promptly returned to 97% and, immediately after intubation, the heart rate was found to be 103 beats/min and the arterial BP 162/102 mmHg. At the end of surgery, spontaneous ventilation returned and the patient was allowed to breathe 100% oxygen via the tracheal tube until he awoke, when his trachea was extubated. PMID:25886433

  10. Modelling of Seismic and Resistivity Responses during the Injection of CO2 in Sandstone Reservoir

    NASA Astrophysics Data System (ADS)

    Omar, Muhamad Nizarul Idhafi Bin; Almanna Lubis, Luluan; Nur Arif Zanuri, Muhammad; Ghosh, Deva P.; Irawan, Sonny; Regassa Jufar, Shiferaw

    2016-07-01

    Enhanced oil recovery plays vital role in production phase in a producing oil field. Initially, in many cases hydrocarbon will naturally flow to the well as respect to the reservoir pressure. But over time, hydrocarbon flow to the well will decrease as the pressure decrease and require recovery method so called enhanced oil recovery (EOR) to recover the hydrocarbon flow. Generally, EOR works by injecting substances, such as carbon dioxide (CO2) to form a pressure difference to establish a constant productive flow of hydrocarbon to production well. Monitoring CO2 performance is crucial in ensuring the right trajectory and pressure differences are established to make sure the technique works in recovering hydrocarbon flow. In this paper, we work on computer simulation method in monitoring CO2 performance by seismic and resistivity model, enabling geoscientists and reservoir engineers to monitor production behaviour as respect to CO2 injection.