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Sample records for confined test section

  1. Section 1. Confinement systems

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Major experimental and theoretical results achieved by the Controlled Thermonuclear Research (CTR) program at Lawrence Livermore Laboratory during FY 1975 gave the greatest encouragement to date that the ultimate goal of a deuterium-tritium-fueled mirror reactor can be reached. In the experimental program, the year was characterized by unusually important physics results from the 2XIIB experiment and by significant steps in the plan to change the Baseball II mode of operation. The stabilization of ion-cyclotron instabilities in the 2XIIB experiment by the introduction of an auxiliary warm plasma permitted the buildup of a high-temperature, high-density plasma with an n tau parameter an order of magnitude larger than the 2XII experiment.I In the Baseball II experiment, preliminary tests and computer predictions indicated that a dense, transient, target plasma can be created by laser irradiation of a pellet in midflight through the center of the Baseball confinement zone

  2. Technical concept for a Greater Confinement Disposal test facility

    International Nuclear Information System (INIS)

    Hunter, P.H.

    1982-01-01

    For the past two years, Ford, Bacon and Davis has been performing technical services for the Department of Energy at the Nevada Test Site in specific development of defense low-level waste management concepts for greater confinement disposal concept with particular application to arid sites. The investigations have included the development of Criteria for Greater Confinement Disposal, NVO-234, which was published in May of 1981 and the draft of the technical concept for Greater Confinement Disposal, with the latest draft published in November 1981. The final draft of the technical concept and design specifications are expected to be published imminently. The document is prerequisite to the actual construction and implementation of the demonstration facility this fiscal year. The GCD Criteria Document, NVO-234 is considered to contain information complimentary and compatible with that being developed for the reserved section 10 CFR 61.51b of the NRCs proposed licensing rule for low level waste disposal facilities

  3. Glass solidification material confinement test device

    International Nuclear Information System (INIS)

    Namiki, Shigekazu.

    1997-01-01

    In a device for confining glass solidification materials, a pipeline connecting a detection vessel and a detector is formed to have a double walled structure, and air blowing holes are formed on the wall of the inner pipe, and an air supply mechanism is connected to inner and outer pipes for supplying blowing air thereby preventing deposition on the inner pipe wall. The air blowing holes are formed by constituting the pipe by using a porous sintered material and porous portions thereof are defined as the air blowing holes, or holes are formed on the pipe wall made of a metal by machining. A blowing boundary layer is formed by blowing the supplied air along the pipe wall of the inner pipe, by which deposition of the sucked materials to the inner wall of the inner pipe is prevented, and all of the materials sucked from the detection vessel are collected to the detector. In addition, an air exit pipe is formed into a double walled structure so as to be supplied blowing air from the air supply mechanism thereby enabling to prevent deposition of sucked materials more reliably. (N.H.)

  4. Confirmation test on confinement performance of improved glove box

    International Nuclear Information System (INIS)

    Miura, S.; Kanazawa, J.; Nakajima, M.; Sakuno, K.; Miyata, H.

    1995-01-01

    Glove boxes are used at nuclear facilities to confine radioactive materials by ensuring a high level of airtightness and negative internal pressure. The allowable rate of air leakage is 0.1% vol/hr or less at the pre-service inspection. The negative pressure value is normally maintained at about -30 mm H 2 O. Structural strength and confinement reliability of glove boxes during earthquake are major concerns, and most important glove boxes are designed to withstand seismic class A events is Japan. This paper describes vibration tests done to confirm that improve large-sized glove boxes maintain their confinement performance and structural strength even during earthquake and that the design analysis methods used are appropriate. (author). 1 ref., 6 figs., 3 tabs

  5. Nevada Test Site experience with greater confinement disposal

    International Nuclear Information System (INIS)

    Dickman, P.T.; Boland, J.R.

    1987-01-01

    In 1980, the Nevada Test Site (NTS) began a project to develop an improved disposal method for high specific activity (HSA) low-level wastes (LLW), e.g. tritium wastes. Past experience with the shallow land burial (SLB) of tritium wastes showed detectable concentrations appearing at trench surfaces. In 1981, the Greater Confinement Disposal Test (GCDT) was initiated to demonstrate the disposal of HSA wastes considered unsuitable for SLB. The project had two specific goals: (1) develop and demonstrate the operational technology for use of large-diameter boreholes for greater confinement disposal (GCD), and (2) conduct research necessary to quantify the effective improvement provided by GCD over SLB. While the long-term impacts may be insignificant for short-lived nuclides, the operational impacts may be a major limiting factor. For example, under 10 CFR 61 up to 700 Ci/m 3 of cobalt-60 may be disposed in SLB as Class A wastes; however, an unshielded waste package containing this amount of cobalt-60 would have an external radiation level of over 5000 R/h making it impossible to dispose of without use of a remote handling systems. In developing the GCDT, the authors decided that greater confinement disposal was not to be strictly limited to a category of wastes between low- and high-level, but a variety of problem wastes that could not, or should not, be disposed of by conventional SLB methods. The paper discusses NTS waste disposal history, hazards reduction, and waste management philosophy. 3 tables

  6. Testing of Confining Pressure Impacton Explosion Energy of Explosive Materials

    Science.gov (United States)

    Drzewiecki, Jan; Myszkowski, Jacek; Pytlik, Andrzej; Pytlik, Mateusz

    2017-06-01

    This paper presents the results of testing the explosion effects of two explosive charges placed in an environment with specified values of confining pressure. The aim of this study is to determine the impact of variable environmental conditions on the suitability of particular explosives for their use in the prevention of natural hazards in hard coal mining. The research results will contribute to improving the efficiency of currently adopted technologies of natural hazard prevention and aid in raising the level of occupational safety. To carry out the subject matter measurements, a special test stand was constructed which allows the value of the initial pressure inside the chamber, which constitutes its integral part, to be altered before the detonation of the charge being tested. The obtained characteristics of the pressure changes during the explosion of the analysed charge helped to identify the work (energy) which was produced during the process. The test results are a valuable source of information, opening up new possibilities for the use of explosives, the development of innovative solutions for the construction of explosive charges and their initiation.

  7. Photoionization cross section in a spherical quantum dot: Effects of some parabolic confining electric potentials

    Directory of Open Access Journals (Sweden)

    M. Tshipa

    2017-12-01

    Full Text Available A theoretical investigation of the effects of spatial variation of confining electric potential on photoionization cross section (PCS in a spherical quantum dot is presented. The potential profiles considered here are the shifted parabolic potential and the inverse lateral shifted parabolic potential compared with the well-studied parabolic potential. The primary findings are that parabolic potential and the inverse lateral shifted parabolic potential blue shift the peaks of the PCS while the shifted parabolic potential causes a red shift.

  8. An experiment to test centrifugal confinement for fusion

    International Nuclear Information System (INIS)

    Ellis, R.F.; Hassam, A.B.; Messer, S.; Osborn, B.R.

    2001-01-01

    The basic idea of centrifugal confinement is to use centrifugal forces from supersonic rotation to augment conventional magnetic confinement. Optimizing this 'knob' results in a fusion device that features four advantages: steady state, no disruptions, superior cross-field confinement, and a simpler coil configuration. The idea rests on two prongs: first, centrifugal forces can confine plasmas to desired regions of shaped magnetic fields; second, the accompanying large velocity shear can stabilize even magnetohydrodynamic (MHD) instabilities. A third feature is that the velocity shear also viscously heats the plasma; no auxiliary heating is necessary to reach fusion temperatures. Regarding transport, the velocity shear can also quell microturbulence, leading to fully classical confinement, as there are no neoclassical effects. Classical parallel electron transport then sets the confinement time. These losses are minimized by a large Pastukhov factor resulting from the deep centrifugal potential well: at Mach 4-5, the Lawson criterion is accessible. One key issue is whether velocity shear will be sufficient by itself to stabilize MHD interchanges. Numerical simulations indicate that laminar equilibria can be obtained at Mach numbers of 4-5 but that the progression toward laminarity with increasing Mach number is accompanied by residual convection from the interchanges. The central goal of the Maryland Centrifugal Torus (MCT) [R. F. Ellis et al., Bull. Am. Phys. Soc. 44, 48 (1998)] is to obtain MHD stability from velocity shear. As an assist to accessing laminarity, MCT will incorporate two unique features: plasma elongation and toroidal magnetic field. The former raises velocity shear efficiency, and modest magnetic shear should suppress residual convection

  9. Electron-detachment cross sections of halogen negative-ion projectiles for inertial confinement fusion

    Science.gov (United States)

    Sant'Anna, M. M.; Zappa, F.; Santos, A. C. F.; de Barros, A. L. F.; Wolff, W.; Coelho, L. F. S.; de Castro Faria, N. V.

    2004-07-01

    Negative-ion beams have recently been suggested as sources of high-energy heavy atoms to be used as drivers for inertial confinement fusion (ICF). Owing to their electron affinities limited to a few eV, anions can be efficiently photo-detached in the vicinity of the fusion chamber, with the resulting high-velocity neutral projectiles following ballistic trajectories towards the hydrogen pellet target. Electron-detachment cross sections are needed as parameters to estimate the beam attenuation in the path from the ion source to the hydrogen pellet. Halogen anions are possible projectile choices. In this paper we present experimental data for total electron-detachment cross sections for F-, Cl-, Br- and I- ions incident on N2, in the 0.94-74 keV u-1 energy range. Our measurements can benchmark theory on anion electron detachment at intermediate to high velocities. Comparison between different projectiles shows very similar collision velocity dependencies. A simple geometrical scaling is presented, providing an estimate for electron-detachment cross sections at the MeV u-1 energy range. The presented scaling indicates that the vacuum requirements due to the use of halogen anions for ICF are less critical than previously suggested.

  10. Electron-detachment cross sections of halogen negative-ion projectiles for inertial confinement fusion

    International Nuclear Information System (INIS)

    Sant'Anna, M M; Zappa, F; Santos, A C F; Barros, A L F de; Wolff, W; Coelho, L F S; Faria, N V de Castro

    2004-01-01

    Negative-ion beams have recently been suggested as sources of high-energy heavy atoms to be used as drivers for inertial confinement fusion (ICF). Owing to their electron affinities limited to a few eV, anions can be efficiently photo-detached in the vicinity of the fusion chamber, with the resulting high-velocity neutral projectiles following ballistic trajectories towards the hydrogen pellet target. Electron-detachment cross sections are needed as parameters to estimate the beam attenuation in the path from the ion source to the hydrogen pellet. Halogen anions are possible projectile choices. In this paper we present experimental data for total electron-detachment cross sections for F - , Cl - , Br - and I - ions incident on N 2 , in the 0.94-74 keV u -1 energy range. Our measurements can benchmark theory on anion electron detachment at intermediate to high velocities. Comparison between different projectiles shows very similar collision velocity dependencies. A simple geometrical scaling is presented, providing an estimate for electron-detachment cross sections at the MeV u -1 energy range. The presented scaling indicates that the vacuum requirements due to the use of halogen anions for ICF are less critical than previously suggested

  11. Superconductivity: A testing ground for models of confinement

    International Nuclear Information System (INIS)

    Ball, J.S.; Caticha, A.

    1988-01-01

    The interaction of a magnetic monopole-antimonopole pair in a superconductor is calculated as a function of their separation and the value of the Landau-Ginzburg parameter. This direct numerical result is then compared to the bag approximation to the same interaction in a superconducting medium. The actual potential exhibits the same general features as those obtained in the bag calculation. If the bag pressure is used as a phenomenological parameter, rather than the value fixed by the superconducting energy density, the agreement is excellent. Numerically the actual problem was actually no more difficult than the bag calculation. The interaction between magnetic monopoles and antimonopoles in the superconducting vacuum state is similar to the interaction of heavy colored quarks in a flux-confining physical QCD vacuum state. This means that our results are probably a good indication of the general behavior of the QCD potential and of the reliability of the bag approximation in the calculation of this potential. Our results also show that the bag model is a good approximation to a dual superconductor. This indicates that a dual superconducting picture of QCD would lead to the same heavy-quark potential and perhaps retain more of the physics than the bag model

  12. Photoionization of Xe inside C60: Atom-fullerene hybridization, giant cross-section enhancement, and correlation confinement resonances

    International Nuclear Information System (INIS)

    Madjet, Mohamed E.; Renger, Thomas; Hopper, Dale E.; McCune, Matthew A.; Chakraborty, Himadri S.; Rost, Jan-M.; Manson, Steven T.

    2010-01-01

    A theoretical study of the subshell photoionization of the Xe atom endohedrally confined in C 60 is presented. Powerful hybridization of the Xe 5s state with the bottom edge of C 60 π band is found that induces strong structures in the 5s ionization, causing the cross section to differ significantly from earlier results that omit this hybridization. The hybridization also affects the angular distribution asymmetry parameter of Xe 5p ionization near the Cooper minimum. The 5p cross section, on the other hand, is greatly enhanced by borrowing considerable oscillator strength from the C 60 giant plasmon resonance via the atom-fullerene dynamical interchannel coupling. Beyond the C 60 plasmon energy range the atomic subshell cross sections display confinement-induced oscillations in which, over the large 4d shape resonance region, the dominant 4d oscillations induce their ''clones'' in all degenerate weaker channels known as correlation confinement resonances.

  13. Analysis of confinement effects for in-water seismic tests on PWR fuel assemblies

    International Nuclear Information System (INIS)

    Broc, Daniel; Queval, Jean-Claude; Rigaudeau, J.; Viallet, E.

    2001-01-01

    In the framework of a comprehensive program on the seismic behaviour of the PWR reactor cores, tests have been performed on a row of six PWR fuel assemblies, with two confinement configurations in water. Global fluid motion along the row is not allowed in the 'full confinement configuration', and is allowed in the 'lateral confinement configuration'. The seismic test results show that the impact forces at assembly grid levels are significantly smaller with the full confinement. This is due to damping, which is found to be larger in this configuration where the average fluid velocity inside the assembly (around the rods) is itself larger. We present analyses of these phenomena from theoretical and experimental standpoint. This involves both fluid models and structural models of the assembly row. (author)

  14. Scale testing of a partially confined blast chamber

    CSIR Research Space (South Africa)

    Grundling, W

    2012-10-01

    Full Text Available into possession of a decommissioned submarine section from the Emily Hobhouse. The hull segment was converted into a diagnostic tool by restraining it to a concrete base with one end of the chamber sealed off by means of a reinforced concrete wall. Explosive...

  15. Initial confinement studies of ohmically heated plasmas in the Tokamak Fusion Test Reactor

    International Nuclear Information System (INIS)

    Efthimion, P.C.; Bell, M.; Blanchard, W.R.

    1984-06-01

    Initial operation of the Tokamak Fusion Test Reactor (TFTR) has concentrated upon confinement studies of ohmically heated hydrogen and deuterium plasmas. Total energy confinement times (tau/sub E/) are 0.1 to 0.2 s for a line-average density range (anti n/sub e/) of 1 to 2.5 x 10 19 m -3 with electron temperatures of T/sub e/(o) approx. 1.2 to 2.2 keV, ion temperatures of T/sub i/(o) approx. 0.9 to 1.5 keV, and Z/sub eff/ approx. 3. A comparison of PLT, PDX, and TFTR plasma confinement supports a dimension-cubed scaling law

  16. A novel method for estimating soil precompression stress from uniaxial confined compression tests

    DEFF Research Database (Denmark)

    Lamandé, Mathieu; Schjønning, Per; Labouriau, Rodrigo

    2017-01-01

    . Stress-strain curves were obtained by performing uniaxial, confined compression tests on undisturbed soil cores for three soil types at three soil water potentials. The new method performed better than the Gompertz fitting method in estimating precompression stress. The values of precompression stress...... obtained from the new method were linearly related to the maximum stress experienced by the soil samples prior to the uniaxial, confined compression test at each soil condition with a slope close to 1. Precompression stress determined with the new method was not related to soil type or dry bulk density......) Assessing the utility of the numerical method by comparison with the Gompertz method; (ii) Comparing the estimated precompression stress to the maximum preload of test samples; (iii) Determining the influence that soil type, bulk density and soil water potential have on the estimated precompression stress...

  17. Second performance assessment iteration of the Greater Confinement Disposal facility at the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Baer, T.A.; Emery, J.N. [GRAM, Inc., Albuquerque, NM (United States); Price, L.L. [Science Applications International Corp., Albuquerque, NM (United States); Olague, N.E. [Sandia National Labs., Albuquerque, NM (United States)

    1994-04-01

    The Greater Confinement Disposal (GCD) facility was established in Area 5 at the Nevada Test Site for containment of waste inappropriate for shallow land burial. Some transuranic (TRU) waste has been disposed of at the GCD facility, and compliance of this disposal system with EPA regulation 40 CFR 191 must be evaluated. We have adopted an iterative approach in which performance assessment results guide site data collection, which in turn influences the parameters and models used in performance assessment. The first iteration was based upon readily available data, and indicated that the GCD facility would likely comply with 40 CFR 191 and that the downward flux of water through the vadose zone (recharge) had a major influence on the results. Very large recharge rates, such as might occur under a cooler, wetter climate, could result in noncompliance. A project was initiated to study recharge in Area 5 by use of three environmental tracers. The recharge rate is so small that the nearest groundwater aquifer will not be contaminated in less than 10,000 years. Thus upward liquid diffusion of radionuclides remained as the sole release pathway. This second assessment iteration refined the upward pathway models and updated the parameter distributions based upon new site information. A new plant uptake model was introduced to the upward diffusion pathway; adsorption and erosion were also incorporated into the model. Several modifications were also made to the gas phase radon transport model. Plutonium solubility and sorption coefficient distributions were changed based upon new information, and on-site measurements were used to update the moisture content distributions. The results of the assessment using these models indicate that the GCD facility is likely to comply with all sections of 40 CFR 191 under undisturbed conditions.

  18. Transient drawdown solution for a constant pumping test in finite two-zone confined aquifers

    Directory of Open Access Journals (Sweden)

    C.-T. Wang

    2012-02-01

    Full Text Available The drawdown solution has been widely used to analyze pumping test data for the determination of aquifer parameters when coupled with an optimization scheme. The solution can also be used to predict the drawdown due to pumping and design the dewatering system. The drawdown solution for flow toward a finite-radius well with a skin zone in a confined aquifer of infinite extent in radial direction had been developed before. To our best knowledge, the drawdown solution in confined aquifers of finite extent with a skin zone so far has never before been presented in the groundwater literature. This article presents a mathematical model for describing the drawdown distribution due to a constant-flux pumping from a finite-radius well with a skin zone in confined aquifers of finite extent. The analytical solution of the model is developed by applying the methods of Laplace transforms, Bromwich contour integral, and residue theorem. This solution can be used to investigate the effects of finite boundary and conductivity ratio on the drawdown distribution. In addition, the inverse relationship between Laplace- and time-domain variables is used to develop the large time solution which can reduce to the Thiem solution if there is no skin zone.

  19. Evaluation of FRP Confinement Models for Substandard Rectangular RC Columns Based on Full-Scale Reversed Cyclic Lateral Loading Tests in Strong and Weak Directions

    Directory of Open Access Journals (Sweden)

    Hamid Farrokh Ghatte

    2016-09-01

    Full Text Available Although many theoretical and experimental studies are available on external confinement of columns using fiber-reinforced polymer (FRP jackets, as well as numerous models proposed for the axial stress-axial strain relation of concrete confined with FRP jackets, they have not been validated with a sufficient amount and variety of experimental data obtained through full-scale tests of reinforced concrete (RC columns with different geometrical and mechanical characteristics. Particularly, no systematical experimental data have been presented on full-scale rectangular substandard RC columns subjected to reversed cyclic lateral loads along either their strong or weak axes. In this study, firstly, test results of five full-scale rectangular substandard RC columns with a cross-sectional aspect ratio of two (300 mm × 600 mm are briefly summarized. The columns were tested under constant axial load and reversed cyclic lateral loads along their strong or weak axes before and after retrofitting with external FRP jackets. In the second stage, inelastic lateral force-displacement relationships of the columns are obtained analytically, making use of the plastic hinge assumption and different FRP confinement models available in the literature. Finally, the analytical findings are compared with the test results for both strong and weak directions of the columns. Comparisons showed that use of different models for the stress-strain relationship of FRP-confined concrete can yield significantly non-conservative or too conservative retrofit designs, particularly in terms of deformation capacity.

  20. COMPLETION OF THE TRANSURANIC GREATER CONFINEMENT DISPOSAL BOREHOLE PERFORMANCE ASSESSMENT FOR THE NEVADA TEST SITE

    International Nuclear Information System (INIS)

    Colarusso, Angela; Crowe, Bruce; Cochran, John R.

    2003-01-01

    Classified transuranic material that cannot be shipped to the Waste Isolation Pilot Plant in New Mexico is stored in Greater Confinement Disposal boreholes in the Area 5 Radioactive Waste Management Site on the Nevada Test Site. A performance assessment was completed for the transuranic inventory in the boreholes and submitted to the Transuranic Waste Disposal Federal Review Group. The performance assessment was prepared by Sandia National Laboratories on behalf of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office using an iterative methodology that assessed radiological releases from the intermediate depth disposal configuration against the regulatory requirements of the 1985 version of 40 CFR 191 of the U.S. Environmental Protection Agency. The transuranic materials are stored at 21 to 37 m depth (70 to 120 ft) in large diameter boreholes constructed in the unsaturated alluvial deposits of Frenchman Flat. Hydrologic processes that affect long- term isolation of the radionuclides are dominated by extremely slow upward rates of liquid/vapor advection and diffusion; there is no downward pathway under current climatic conditions and there is no recharge to groundwater under future ''glacial'' climatic conditions. A Federal Review Team appointed by the Transuranic Waste Disposal Federal Review Group reviewed the Greater Confinement Disposal performance assessment and found that the site met the majority of the regulatory criteria of the 1985 and portions of the 1993 versions of 40 CFR 191. A number of technical and procedural issues required development of supplemental information that was incorporated into a final revision of the performance assessment. These issues include inclusion of radiological releases into the complementary cumulative distribution function for the containment requirements associated with drill cuttings from inadvertent human intrusion, verification of mathematical models used in the performance

  1. Test of RIPL-2 cross section calculations

    International Nuclear Information System (INIS)

    Herman, M.

    2002-01-01

    The new levels and optical segments and microscopic HF-BCS level densities (part of the density segment) were tested in practical calculations of cross sections for neutron induced reactions on 22 targets (40-Ca, 47-Ti, 52-Cr, 55-Mn, 58-Ni, 63-Cu, 71-Ga, 80-Se, 92-Mo, 93-Nb, 100-Mo, 109-Ag, 114-Cd, 124-Sn, 127-I, 133-Cs, 140-Ce, 153-Eu, 169-Tm, 186-W, 197-Au, 208-Pb). For each target all reactions involving up to 3 neutron, 1 proton and 1 α-particle emissions (subject to actual reaction thresholds) were considered in the incident energy range from 1 keV up to 20 MeV (in some cases up to 27 MeV). In addition, total, elastic, and neutron capture cross sections were calculated

  2. Complot test section outlet CFD optimization (pre - test and dimensioning)

    International Nuclear Information System (INIS)

    Profir, M. M.; Moreau, V.; Kennedy, G.

    2013-01-01

    In the framework of the FP7 MAXSIMA European project, the COMPLOT (COMPonent LOop Testing) LBE experimental facility is employed for thermal-hydraulic experiments aimed to test and qualify, among other components, a buoyancy driven safety/control rods (SR/CR) system, as key components for the safe operation of the MYRRHA reactor. This paper focuses mainly on a simplified CFD representation of the SR test section outlet in order to optimise it for the testing program. Parametric cases, associated with different positions of the SR assembly have been set up and analysed. A quasi-static analysis has been performed for each case, accounting for the LBE volume displaced by the insertion of the SR bundle, by introducing appropriately positioned additional mass sources. Velocity and pressure fields, as well as pressure drop magnitudes and mass flow rates through relevant guide tube hole outlets have been calculated and compared. The CFD analysis proved that the outer boundary of the test section does not impact the expected performance of the SR (rapid transient downward insertion). Preliminary simulations reproducing the timely repositioning of the SR/CR in COMPLOT using procedures of automatic volume mesh regeneration, consistently with the rod imposed displacement, are illustrated. (authors)

  3. Problems With Section Two ITP TOEFL Test

    Directory of Open Access Journals (Sweden)

    Rizki Ananda

    2016-03-01

    Full Text Available This study was designed to investigate (1 the difficulties faced by EFL university students with section two of the ITP, and (2 whether part A or part B was more difficult for them and why. A number of 26 students from two different universities, Syiah Kuala University and the State Islamic University Ar-Raniry were the samples for the test. The data was obtained from a multiple choice questionnaire test consisting of 46 questions, each with 4 answers to choose from. The results showed that inversions (12%, subject-verb agreements (10%, adverb clause connectors (7%, passives (6%, reduced adjective clauses (5%, parallel structures (5% and use of verbs (5% were the most difficult questions for the students. Furthermore, they felt that part B was more difficult than part A, as finding an error in a sentence was harder than completing a sentence from a multiple choice. Furthermore, the length of questions in part A did not affect the amount of time the students spent to complete part A and did not cause them to panic. Also, unfamiliar words in part A were not regarded as a problem by the students. Hence, TOEFL teachers and trainers are highly encouraged to pay more attention to doing study exercises for the seven topics with the highest percentages above in part A and also to more practice for part B.

  4. Confined photovoltaic fields in a photo-responsive liquid crystal test cell

    Science.gov (United States)

    Habibpourmoghadam, Atefeh; Jiao, Lin; Omairat, Faissal; Evans, Dean R.; Lucchetti, Liana; Reshetnyak, Viktor; Lorenz, Alexander

    2017-08-01

    Exciting experimental results on the response properties of hybridized photo responsive liquid crystal test cells are reported, where iron doped lithium niobate substrates were used to photo generate electric fields and indium tin oxide coated cover glasses were used to confine these photo generated fields in a liquid crystal layer. Samples were investigated in a modified inverted optical polarizing microscope with white probe light (crossed polarizers) and exposed with a Gaussian laser beam focused to a small spot (14 μm FWHM). Test cells filled with nematic LC showed homeotropic director alignment. Upon exposure, this alignment was maintained at the exposure spot center and the LC director was selectively realigned in a surrounding single ring. This ring had a thickness of a few microns and its diameter increased with increasing exposure intensity (112 μm at 0.7 mW, 204 μm at 1.1 mW). This characteristic director realignment was traced back to the optically generated electric field distributions by simulations. In samples filled with chiral nematic LC, uniformly standing helix alignment was found. Textural transitions were induced at the focus position, which again led to the formation of well-defined circular defects. We could show that these defects can be permanently stored within the chiral nematic LC. Polarized optical microscopy of a rotated sample revealed that a point like defect with +1 topological charge was enclosed in each of these defects. Photovoltaic fields generated in small lithium niobate particles dispersed in a LC were found to cause promising optical responses and particle movement.

  5. Disposal configuration options for future uses of greater confinement disposal at the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Price, L. [Science Applications International Corp., Albuquerque, NM (United States)

    1994-09-01

    The US Department of Energy (DOE) is responsible for disposing of a variety of radioactive and mixed wastes, some of which are considered special-case waste because they do not currently have a clear disposal option. The DOE`s Nevada Field Office contracted with Sandia National Laboratories to investigate the possibility of disposing of some of this special-case waste at the Nevada Test Site (NTS). As part of this investigation, a review of a near-surface and subsurface disposal options that was performed to develop alternative disposal configurations for special-case waste disposal at the NTS. The criteria for the review included (1) configurations appropriate for disposal at the NTS; (2) configurations for disposal of waste at least 100 ft below the ground surface; (3) configurations for which equipment and technology currently exist; and (4) configurations that meet the special requirements imposed by the nature of special-case waste. Four options for subsurface disposal of special-case waste are proposed: mined consolidated rock, mined alluvium, deep pits or trenches, and deep boreholes. Six different methods for near-surface disposal are also presented: earth-covered tumuli, above-grade concrete structures, trenches, below-grade concrete structures, shallow boreholes, and hydrofracture. Greater confinement disposal (GCD) in boreholes at least 100 ft deep, similar to that currently practiced at the GCD facility at the Area 5 Radioactive Waste Management Site at the NTS, was retained as the option that met the criteria for the review. Four borehole disposal configurations are proposed with engineered barriers that range from the native alluvium to a combination of gravel and concrete. The configurations identified will be used for system analysis that will be performed to determine the disposal configurations and wastes that may be suitable candidates for disposal of special-case wastes at the NTS.

  6. A Study of Aerodynamics in Kevlar-Wall Test Sections

    OpenAIRE

    Brown, Kenneth Alexander

    2014-01-01

    This study is undertaken to characterize the aerodynamic behavior of Kevlar-wall test sections and specifically those containing two-dimensional, lifting models. The performance of the Kevlar-wall test section can be evaluated against the standard of the hard-wall test section, which in the case of the Stability Wind Tunnel (SWT) at Virginia Tech can be alternately installed or replaced by the Kevlar-wall test section. As a first step towards the evaluation of the Kevlar-wall test section aer...

  7. Experimental tests of confinement scale invariance on JET, DIIID, ASDEX Upgrade and CMOD

    International Nuclear Information System (INIS)

    Christiansen, J.P.; Cordey, J.G.; Budny, R.

    2001-01-01

    An international collaboration between JET, DIIID, AUG and CMOD has resulted in four sets of Tokamak discharges which are approximately identical as regards a set of dimensionless plasma variables. The data demonstrates some measure of scale invariance of local and global confinement but a more accurate matching of scaled density, power etc. is required to make firmer conclusions. (author)

  8. Evaluation tests for photovoltaic concentrator receiver sections and modules

    Energy Technology Data Exchange (ETDEWEB)

    Woodworth, J.R.; Whipple, M.L.

    1992-06-01

    Sandia has developed a third-generation set of specifications for performance and reliability testing of photovoltaic concentrator modules. Several new requirements have been defined. The primary purpose of the tests is to screen new concentrator designs and new production runs for susceptibility to known failure mechanisms. Ultraviolet radiation testing of materials precedes receiver section and module performance and environmental tests. The specifications include the purpose, procedure, and requirements for each test. Recommendations for future improvements are presented.

  9. Greater confinement disposal of high activity and special case wastes at the Nevada Test Site: A unified migration assessment approach

    International Nuclear Information System (INIS)

    Davis, P.A.; Olague, N.E.; Johnson, V.L.; Dickman, P.T.; O'Neill, L.J.

    1993-01-01

    The Department of Energy's Nevada Field Office has disposed of a small quantity of high activity and special case wastes using Greater Confinement Disposal facilities in Area 5 of the Nevada Test Site. Because some of these wastes are transuranic radioactive wastes, the Environmental Protection Agency standards for their disposal under 40 CFR Part 191 which requires a compliance assessment. In conducting the 40 CFR Part 191 compliance assessment, review of the Greater Confinement Disposal inventory revealed potentially land disposal restricted hazardous wastes. The regulatory options for disposing of land disposal restricted wastes consist of (1) treatment and monitoring, or (2) developing a no-migration petition. Given that the waste is already buried without treatment, a no-migration petition becomes the primary option. Based on a desire to minimize costs associated with site characterization and performance assessment, a single approach has been developed for assessing compliance with 40 CFR Part 191, DOE Order 5820.2A (which regulates low-level radioactive wastes contained in Greater Confinement Disposal facilities) and developing a no-migration petition. The approach consists of common points of compliance, common time frame for analysis, and common treatment of uncertainty. The procedure calls for conservative bias of modeling assumptions, including model input parameter distributions and adverse processes and events that can occur over the regulatory time frame, coupled with a quantitative treatment of data and parameter uncertainty. This approach provides a basis for a defensible regulatory decision. In addition, the process is iterative between modeling and site characterization activities, where the need for site characterization activities is based on a quantitative definition of the most important and uncertain parameters or assumptions

  10. Testing the saprobity hypothesis in a Mediterranean lagoon: effects of confinement and organic enrichment on benthic communities.

    Science.gov (United States)

    Foti, A; Fenzi, G A; Di Pippo, F; Gravina, M F; Magni, P

    2014-08-01

    The macrobenthic community was compared at four sites characterized by varying degrees of freshwater input, organic enrichment and confinement in the Cabras lagoon (Sardinia, Italy). Three sites, riverine (C1), confined (C2) and seaward (C3), were studied on two dates of summer 2010 and on two dates of winter 2011. A fourth site (C12), representative of the central sector of the Cabras lagoon, was included in this study using the extensive historical datasets at our disposal from previously published work. We aimed to test the hypothesis that (1) the benthos is distributed according to the recently proposed concept of habitat saprobity for coastal lagoons that unifies the Pearson-Rosenberg (sensu organic enrichment) and Guélorget-Perthuisot (sensu confinement) models, and (2) indicator species of different saprobic levels can be identified among dominant species occurring along the saprobity gradient. Salinity was also considered as an additional agent of selection in brackish environments. Irrespective of significant seasonal changes within each site, our results highlighted major environmental and biotic differences between sites. At the northward riverine site (C1), most affected by freshwater input and with limited organic matter (OM) enrichment, Corophium orientale was the single dominant species. The most confined site (C2) was characterized by the highest levels of sedimentary OM and benthic Chlorophyll-a and by mesohaline conditions; the site was inhabited mainly by the halolimnobic Hediste diversicolor and Hydrobia spp. Site C12, characterized by a high OM load and high residence time, was dominated by the opportunistic detritivorous Alitta succinea and Polydora ciliata. At the southernmost seaward site (C3) the considerable seawater renewal, resulting in high salinity (only in summer) and limited OM load, favored a much more diverse macrobenthic assemblage, essentially composed of both marine species, such as Corophium insidiosum, Gammarus aequicauda

  11. Live Imaging and Heating of Confined RDX and HMX Crystals Until Reaction Using the Dual Windowed Test Vehicle

    Science.gov (United States)

    Stennett, Chris; Cook, Malcolm; Cheese, Philip; Wood, Andrew; White, Nathan; Reeves, Tom

    2017-06-01

    A high fidelity live camera feed recording RDX and HMX crystals, measuring 1 mm thick and 15 mm in diameter, decomposing while heavily confined and subjected to various heating rates until a reaction occurs has been analysed. Video records reveal unexpected behaviour in both RDX and HMX crystals prior to ignition. Three distinct stages can be observed: phase changes and melting; slow, flameless decomposition with production of gaseous intermediates; and finally burning with a luminous flame of the gaseous intermediates. Tests with pure RDX and HMX crystals reveal pockets of gaseous materials forming above the molten and bubbling nitramine, before a flame appears at one side then burns inwards in an apparent conductive manner at a few metres per second. This causes the remaining bubbling nitramine to be compressed. Violent reaction appears to occur via a bubble collapse mechanism. The violence of this event is dependent on the loss of confinement; if it fails in the first or second phase the reaction is less violent than if the third phase is reached. The third phase burning reaction has associated pressure waves, which is presumed oscillation of the flame front, leading to wave interactions, pressure spikes and ultimately a violent reaction.

  12. A General Semi-Analytical Solution for Three Types of Well Tests in Confined Aquifers with a Partially Penetrating Well

    Directory of Open Access Journals (Sweden)

    Shaw-Yang Yang Hund-Der Yeh

    2012-01-01

    Full Text Available This note develops a general mathematical model for describing the transient hydraulic head response for constant-head test, constant-flux test, and slug test in a radial confined aquifer system with a partially penetrating well. The Laplace-domain solution for the model is derived by applying the Laplace transform with respect to time and finite Fourier cosine transform with respect to the z-direction. This new solution has been shown to reduce to the constant-head test when discounting the wellbore storage and maintaining a constant well water level. This solution can also be reduced to the constant-flux test solution when discounting the wellbore storage and keeping a constant pumping rate in the well. Moreover, the solution becomes the slug test solution when there is no pumping in the well. This general solution can be used to develop a single computer code to estimate aquifer parameters if coupled with an optimization algorithm or to assess the effect of well partial penetration on hydraulic head distribution for three types of aquifer tests.

  13. Well hydraulics in pumping tests with exponentially decayed rates of abstraction in confined aquifers

    Science.gov (United States)

    Wen, Zhang; Zhan, Hongbin; Wang, Quanrong; Liang, Xing; Ma, Teng; Chen, Chen

    2017-05-01

    Actual field pumping tests often involve variable pumping rates which cannot be handled by the classical constant-rate or constant-head test models, and often require a convolution process to interpret the test data. In this study, we proposed a semi-analytical model considering an exponentially decreasing pumping rate started at a certain (higher) rate and eventually stabilized at a certain (lower) rate for cases with or without wellbore storage. A striking new feature of the pumping test with an exponentially decayed rate is that the drawdowns will decrease over a certain period of time during intermediate pumping stage, which has never been seen before in constant-rate or constant-head pumping tests. It was found that the drawdown-time curve associated with an exponentially decayed pumping rate function was bounded by two asymptotic curves of the constant-rate tests with rates equaling to the starting and stabilizing rates, respectively. The wellbore storage must be considered for a pumping test without an observation well (single-well test). Based on such characteristics of the time-drawdown curve, we developed a new method to estimate the aquifer parameters by using the genetic algorithm.

  14. Quark confinement

    International Nuclear Information System (INIS)

    Joos, H.

    1976-07-01

    The main topics of these lectures are: phenomenological approach to quark confinement, standard Lagrangian of hadrondynamics, Lagrangian field theory and quark confinement, classical soliton solutions in a simple model, quantization of extended systems, colour charge screening and quantization on a lattice and remarks on applications. A survey of the scientific publications listed according to the topics until 26 March 1976 is supplemented. (BJ) [de

  15. Vertical Drop Test of a Transport Fuselage Section

    OpenAIRE

    熊倉, 郁夫; KUMAKURA, Ikuo

    2002-01-01

    The NAL Structures and Materials Research Center conducted a vertical drop test of a fuselage section from a YS-11A transport airplane in December 2001. This test program is part of research into the structural crashworthiness of transport aircraft in the event of a crash accident, one of the subjects of Aviation Safety and Environmental Compatibility Technology Research(ASET) at NAL. Cooperative research related to this test program has also been carried out by NAL and Kawasaki Heavy Industr...

  16. First-wall, blanket, and shield engineering test program for magnetically confined fusion power reactors

    International Nuclear Information System (INIS)

    Maroni, V.A.

    1980-01-01

    The key engineering areas identified for early study relate to FW/B/S system thermal-hydraulics, thermomechnics, nucleonics, electromagnetics, assembly, maintenance, and repair. Programmatic guidance derived frm planning exercises involving over thirty organizations (laboratories, industries, and universities) has indicated (1) that meaningful near term engineering testing should be feasible within the bounds of a modest funding base, (2) that there are existing facilities and expertise which can be profitably utilized in this testing, and (3) that near term efforts should focus on the measurement of engineering data and the verification/calibration of predictive methods for anticipated normal operational and transient FW/B/S conditions. The remainder of this paper discusses in more detail the planning strategies, proposed approach to near term testing, and longer range needs for integrated FW/B/S test facilities

  17. Relating pressure measurements to phenomena observed in high speed video recordings during tests of explosive charges in a semi-confined blast chamber

    CSIR Research Space (South Africa)

    Mostert, FJ

    2012-09-01

    Full Text Available Tests with explosive charges of 0.5 kg and 2 kg were conducted in the semi-confined blast chamber at the CSIR DBEL test range. Pressure measurements were obtained with side-on and face-on sensors mounted in the walls of the chamber and high speed...

  18. Modeling and Simulation of a Nuclear Fuel Element Test Section

    Science.gov (United States)

    Moran, Robert P.; Emrich, William

    2011-01-01

    "The Nuclear Thermal Rocket Element Environmental Simulator" test section closely simulates the internal operating conditions of a thermal nuclear rocket. The purpose of testing is to determine the ideal fuel rod characteristics for optimum thermal heat transfer to their hydrogen cooling/working fluid while still maintaining fuel rod structural integrity. Working fluid exhaust temperatures of up to 5,000 degrees Fahrenheit can be encountered. The exhaust gas is rendered inert and massively reduced in temperature for analysis using a combination of water cooling channels and cool N2 gas injectors in the H2-N2 mixer portion of the test section. An extensive thermal fluid analysis was performed in support of the engineering design of the H2-N2 mixer in order to determine the maximum "mass flow rate"-"operating temperature" curve of the fuel elements hydrogen exhaust gas based on the test facilities available cooling N2 mass flow rate as the limiting factor.

  19. Plasma confinement

    CERN Document Server

    Hazeltine, R D

    2003-01-01

    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  20. Vertical Drop Test of a YS-11 Fuselage Section

    Science.gov (United States)

    Minegishi, Masakatsu; Kumakura, Ikuo; Iwasaki, Kazuo; Shoji, Hirokazu; Yoshimoto, Norio; Terada, Hiroyuki; Sashikuma, Hirofumi; Isoe, Akira; Yamaoka, Toshihiro; Katayama, Noriaki; Hayashi, Toru; Akaso, Tetsuya

    The Structures and Materials Research Center of the National Aerospace Laboratory of Japan (NAL) and Kawasaki Heavy Industories, Ltd. (KHI) conducted a vertical drop test of a fuselage section cut from a NAMIC YS-11 transport airplane at NAL vertical drop test facility in December 2001. The main objectives of this program were to obtain background data for aircraft cabin safety by drop test of a full-scale fuselage section and to develop computational method for crash simulation. The test article including seats and anthropomorphic test dummies was dropped to a rigid impact surface at a velocity of 6.1 m/s (20 ft/s). The test condition and result were considered to be severe but potentially survivable. A finite element model of this test article was also developed using the explicit nonlinear transient-dynamic analysis code, LS-DYNA3D. An outline of analytical method and comparison of analysis result with drop test data are presented in this paper.

  1. Heavy Section Steel Technology Program. Part II. Intermediate vessel testing

    International Nuclear Information System (INIS)

    Whitman, G.D.

    1975-01-01

    The testing of the intermediate pressure vessels is a major activity under the Heavy Section Steel Technology Program. A primary objective of these tests is to develop or verify methods of fracture prediction, through the testing of selected structures and materials, in order that a valid basis can be established for evaluating the serviceability and safety of light-water reactor pressure vessels. These vessel tests were planned with sufficiently specific objectives that substantial quantitative weight could be given to the results. Each set of testing conditions was chosen so as to provide specific data by which analytical methods of predicting flaw growth, and in some cases crack arrest, could be evaluated. Every practical effort was made to assure that results would be relevant to some aspect of real reactor pressure vessel performance through careful control of material properties, selection of test temperatures, and design of prepared flaws. 5 references

  2. Analysis of a transport fuselage section drop test

    Science.gov (United States)

    Fasanella, E. L.; Hayduk, R. J.; Robinson, M. P.; Widmayer, E.

    1984-01-01

    Transport fuselage section drop tests provided useful information about the crash behavior of metal aircraft in preparation for a full-scale Boeing 720 controlled impact demonstration (CID). The fuselage sections have also provided an operational test environment for the data acquisition system designed for the CID test, and data for analysis and correlation with the DYCAST nonlinear finite-element program. The correlation of the DYCAST section model predictions was quite good for the total fuselage crushing deflection (22 to 24 inches predicted versus 24 to 26 inches measured), floor deformation, and accelerations for the floor and fuselage. The DYCAST seat and occupant model was adequate to approximate dynamic loading to the floor, but a more sophisticated model would be required for good correlation with dummy accelerations. Although a full-section model using only finite elements for the subfloor was desirable, constraints of time and computer resources limited the finite-element subfloor model to a two-frame model. Results from the two-frame model indicate that DYCAST can provide excellent correlation with experimental crash behavior of fuselage structure with a minimum of empirical force-deflection data representing structure in the analytical model.

  3. Critical heat flux experimentation in an annular test section

    International Nuclear Information System (INIS)

    White, J.D.; Levin, A.E.

    1978-01-01

    Steady-state critical heat flux experiments have been performed in the Forced Convection Test Facility (FCTF), an annular test section containing a single electrically heated rod, for the purpose of testing the applicability of existing critical heat flux correlations. Good accuracy has been obtained using the MacBeth-Barnett critical heat flux correlation for annuli, corrected for the ''stepped cosine'' power profile of the heater. The equivalent diameter of the test section, based on the wetted perimeter, is 2.1 cm (0.83 in.); the heated-to-wetted-perimeter ratio is 0.252. The heated length of the heater rod is 366 cm (144 in.). Nominal pressures for the tests have ranged from 7.2 to 15.5 MN/m 2 (1044 to 2250 psia); coolant flow rates have been 0.32 dm 3 /sec (5 gpm), 0.63 dm 3 /sec (10 gpm), and 1.26 dm 3 /sec (20 gpm); and heater powers of 72 kW, 122 kW, and 144 kW have been used. Maximum error in prediction of first observed critical heat flux is 21 percent; rms error is 11.7 percent. Attempts have also been made to predict the occurrence of critical heat flux during blowdowns (depressurization transients) of the FCTF. The results of these predictions are inconclusive at this time

  4. Analysis of a Hybrid Wing Body Center Section Test Article

    Science.gov (United States)

    Wu, Hsi-Yung T.; Shaw, Peter; Przekop, Adam

    2013-01-01

    The hybrid wing body center section test article is an all-composite structure made of crown, floor, keel, bulkhead, and rib panels utilizing the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) design concept. The primary goal of this test article is to prove that PRSEUS components are capable of carrying combined loads that are representative of a hybrid wing body pressure cabin design regime. This paper summarizes the analytical approach, analysis results, and failure predictions of the test article. A global finite element model of composite panels, metallic fittings, mechanical fasteners, and the Combined Loads Test System (COLTS) test fixture was used to conduct linear structural strength and stability analyses to validate the specimen under the most critical combination of bending and pressure loading conditions found in the hybrid wing body pressure cabin. Local detail analyses were also performed at locations with high stress concentrations, at Tee-cap noodle interfaces with surrounding laminates, and at fastener locations with high bearing/bypass loads. Failure predictions for different composite and metallic failure modes were made, and nonlinear analyses were also performed to study the structural response of the test article under combined bending and pressure loading. This large-scale specimen test will be conducted at the COLTS facility at the NASA Langley Research Center.

  5. Finite Element Analysis and Test Results Comparison for the Hybrid Wing Body Center Section Test Article

    Science.gov (United States)

    Przekop, Adam; Jegley, Dawn C.; Rouse, Marshall; Lovejoy, Andrew E.

    2016-01-01

    This report documents the comparison of test measurements and predictive finite element analysis results for a hybrid wing body center section test article. The testing and analysis efforts were part of the Airframe Technology subproject within the NASA Environmentally Responsible Aviation project. Test results include full field displacement measurements obtained from digital image correlation systems and discrete strain measurements obtained using both unidirectional and rosette resistive gauges. Most significant results are presented for the critical five load cases exercised during the test. Final test to failure after inflicting severe damage to the test article is also documented. Overall, good comparison between predicted and actual behavior of the test article is found.

  6. Tests with the second differential pumping section for KATRIN

    Energy Technology Data Exchange (ETDEWEB)

    Lukic, Strahinja [Universitaet Karlsruhe, Institut fuer Experimentelle Kernphysik (Germany)

    2009-07-01

    The KArlsruhe TRItium Neutrino experiment (KATRIN) aims at determining electron-neutrino mass from the beta-decay of tritium with unprecedented sensitivity of 0.2 eV/c{sup 2}. KATRIN comprises a Windowless Gaseous Tritium Source (WGTS), an electron-transport section, two high resolution electrostatic spectrometers and an electron detector. Along the electron-transport section, tritium will be pumped out for reprocessing and reinsertion into the source. Two stages of differential pumping followed by a cryogenic pumping system must reduce the tritium gas flow by a total factor of 10{sup 14} in order to avoid distortion of the electron energy spectrum and contamination of the spectrometers. In particular, the second Differential Pumping Section (DPS2-F) is constructed to reduce the flow of 10{sup -2} mbar l/s at its input by at least a factor of 10{sup 5}. Beside that, DPS2-F will host devices for monitoring the concentration of ions produced in the WGTS and for their removal. In this talk a series of experiments are described that aim at testing gas-flow reduction capabilities of the pumping section, as well as the performance of systems for ion-concentration measurement and for ion removal.

  7. Benchmark experiments to test plutonium and stainless steel cross sections

    International Nuclear Information System (INIS)

    Jenquin, U.P.; Bierman, S.R.

    1978-06-01

    Neutronics calculations of physical systems containing fissionable material in various configurations are often necessary to assess criticality safety and economic parameters. Criticality safety of the material must be assured for all configurations in the fuel fabrication, spent fuel reprocessing, and transportation processes. Integral criticality experiments are utilized to evaluate neutron cross sections, test theoretical methods, and validate calculational procedures. The Nuclear Regulatory Commission (NRC) commissioned Battelle, Pacific Northwest Laboratory (PNL) to ascertain the accuracy of the neutron cross sections for the isotopes of plutonium and the constituents of stainless steel and determine if improvements can be made in application to criticality safety analysis. NRC's particular area of interest is in the transportation of light--water reactor spent fuel assemblies. The project was divided into two tasks. The first task was to define a set of integral experimental measurements (benchmarks). The second task is to use these benchmarks in neutronics calculations such that the accuracy of ENDF/B-IV plutonium and stainless steel cross sections can be assessed. The results of the second task should help to identify deficiencies in the neutron cross sections. The results of the first task are given

  8. Power Enhancement in High Dimensional Cross-Sectional Tests

    Science.gov (United States)

    Fan, Jianqing; Liao, Yuan; Yao, Jiawei

    2016-01-01

    We propose a novel technique to boost the power of testing a high-dimensional vector H : θ = 0 against sparse alternatives where the null hypothesis is violated only by a couple of components. Existing tests based on quadratic forms such as the Wald statistic often suffer from low powers due to the accumulation of errors in estimating high-dimensional parameters. More powerful tests for sparse alternatives such as thresholding and extreme-value tests, on the other hand, require either stringent conditions or bootstrap to derive the null distribution and often suffer from size distortions due to the slow convergence. Based on a screening technique, we introduce a “power enhancement component”, which is zero under the null hypothesis with high probability, but diverges quickly under sparse alternatives. The proposed test statistic combines the power enhancement component with an asymptotically pivotal statistic, and strengthens the power under sparse alternatives. The null distribution does not require stringent regularity conditions, and is completely determined by that of the pivotal statistic. As specific applications, the proposed methods are applied to testing the factor pricing models and validating the cross-sectional independence in panel data models. PMID:26778846

  9. Results of experiments in the THIBO II test section

    International Nuclear Information System (INIS)

    Bojarsky, E.; Deckers, H.; Lehning, H.; Piel, D.; Reiser, H.; Schmidt, L.

    1989-10-01

    It was possible to prove in 1988 in the course of the THIBO I experiments; that under certain operating conditions thermohydraulically induced rod damaging oscillations may occur in sodium cooled Mark II fuel elements. Since May 1989 another THIBO II test series has been performed in a new test section of the sodium loop of the IMF III. The area of the coolant channel was reduced to approximately half its previous surface so that the thermohydraulic conditions come very close to those prevailing in the KNK II reactor. The experiments have shown that even with minor sodium enthalpy raises and low rating, respectively, motions of the fuel pins can be induced. This applies also in cases where the clearance of the pin in the spacer has been set to realistically low values

  10. Commissioning of the Ground Test Accelerator Intertank Matching Section

    International Nuclear Information System (INIS)

    Johnson, K.F.; Sander, O.R.; Atkins, W.H.; Bolme, G.O.; Cole, R.; Connolly, R.; Gilpatrick, J.D.; Ingalls, W.B.; Kersteins, D.; Little, C.; Lohsen, R.A.; Lysenko, W.P.; Mottershead, C.T.; Power, J.; Rusthoi, D.P.; Sandoval, D.P.; Stevens, R.R.; Vaughn, G.; Wadlinger, E.A.; Weiss, R.; Yuan, V.

    1992-01-01

    The Ground Test Accelerator (GTA) has the objective of verifying much of the technology (physics and engineering) required for producing high-brightness, high-current H - beams. GTA commissioning is staged to verify the beam dynamics design of each major accelerator component as it is brought on-line. The commissioning stages are the 35 keV H - injector, the 2.5 MeV Radio Frequency Quadrupole (RFQ), the Intertank Matching Section (IMS), the 3.2 MeV first 2βγ Drift Tube Linac (DTL-1) module, the 8.7 MeV 2βγ DTL (modules 1--5), and the 24 MeV GTA; all 10 DTL modules. Commissioning results from the IMS beam experiments will be presented

  11. Commissioning of the ground test accelerator intertank matching section

    International Nuclear Information System (INIS)

    Johnson, K.F.; Sander, O.R.; Atkins, W.H.; Bolme, G.O.; Cole, R.; Gilpatrick, J.D.; Ingalls, W.B.; Kersteins, D.; Little, C.; Lohsen, R.A.; Lysenko, W.P.; Mottershead, C.T.; Power, J.; Rushoi, D.P.; Sandoval, D.P.; Stevens, R.R.; Vaughn, G.; Wadlinger, E.A.; Yuan, V.; Connelly, R.; Weiss, R.

    1992-01-01

    The Ground Test Accelerator (GTA) has the objective of verifying much of the technology (physics and engineering) required for producing high-brightness, high-current H - beams. GTA commissioning is staged to verify the beam dynamics design of each major accelerator component as it is brought on-line. The commissioning stages are the 35-KeV H - injector, the 2.5-MeV radio-frequency quadrupole (RFQ); the intertank matching section (IMS), the 3.2-MeV first 2-βλ drift-tube linac (DTL-1) module, the 8.7-MeV 2-βλ DTL (modules 1-5), and the 24-MeV GTA (all 10 DTL modules). Commissioning results from the IMS beam experiments are presented. (Author) 10 refs., 6 figs

  12. ATR confinement leakage determination

    International Nuclear Information System (INIS)

    Kuan, P.; Buescher, B.J.

    1998-01-01

    The air leakage rate from the Advanced Test Reactor (ATR) confinement is an important parameter in estimating hypothesized accidental releases of radiation to the environment. The leakage rate must be determined periodically to assure that the confinement has not degraded with time and such determination is one of the technical safety requirements of ATR operation. This paper reviews the methods of confinement leakage determination and presents an analysis of leakage determination under windy conditions, which can complicate the interpretation of the determined leakage rates. The paper also presents results of analyses of building air exchange under windy conditions. High wind can enhance air exchange and this could increase the release rates of radioisotopes following an accident

  13. Performance evaluation testing of wells in the gradient control system at a federally operated Confined Disposal Facility using single well aquifer tests, East Chicago, Indiana

    Science.gov (United States)

    Lampe, David C.; Unthank, Michael D.

    2016-12-08

    The U.S. Geological Survey (USGS) performed tests to evaluate the hydrologic connection between the open interval of the well and the surrounding Calumet aquifer in response to fouling of extraction well pumps onsite. Two rounds of air slug testing were performed on seven monitoring wells and step drawdown and subsequent recovery tests on three extraction wells on a U.S. Army Corps of Engineers Confined Disposal Facility (CDF) in East Chicago, Indiana. The wells were tested in 2014 and again in 2015. The extraction and monitoring wells are part of the gradient control system that establishes an inward gradient around the perimeter of the facility. The testing established a set of protocols that site personnel can use to evaluate onsite well integrity and develop a maintenance procedure to evaluate future well performance.The results of the slug test analysis data indicate that the hydraulic connection of the well screen to the surrounding aquifer material in monitoring wells on the CDF and the reliability of hydraulic conductivity estimates of the surrounding geologic media could be increased by implementing well development maintenance. Repeated air slug tests showed increasing hydraulic conductivity until, in the case of the monitoring wells located outside of the groundwater cutoff wall (MW–4B, MW–11B, MW–14B), the difference in hydraulic conductivity from test to test decreased, indicating the results were approaching the optimal hydraulic connection between the aquifer and the well screen. Hydraulic conductivity values derived from successive tests in monitoring well D40, approximately 0.25 mile south of the CDF, were substantially higher than those derived from wells on the CDF property. Also, values did not vary from test to test like those measured in monitoring wells located on the CDF property, which indicated that a process may be affecting the connectivity of the wells on the CDF property to the Calumet aquifer. Derived hydraulic conductivity

  14. Nonlinear Analysis and Preliminary Testing Results of a Hybrid Wing Body Center Section Test Article

    Science.gov (United States)

    Przekop, Adam; Jegley, Dawn C.; Rouse, Marshall; Lovejoy, Andrew E.; Wu, Hsi-Yung T.

    2015-01-01

    A large test article was recently designed, analyzed, fabricated, and successfully tested up to the representative design ultimate loads to demonstrate that stiffened composite panels with through-the-thickness reinforcement are a viable option for the next generation large transport category aircraft, including non-conventional configurations such as the hybrid wing body. This paper focuses on finite element analysis and test data correlation of the hybrid wing body center section test article under mechanical, pressure and combined load conditions. Good agreement between predictive nonlinear finite element analysis and test data is found. Results indicate that a geometrically nonlinear analysis is needed to accurately capture the behavior of the non-circular pressurized and highly-stressed structure when the design approach permits local buckling.

  15. Magnetic confinement

    Energy Technology Data Exchange (ETDEWEB)

    Batistoni, Paola; De Marco, Francesco; Pieroni, Leonardo (ed.)

    2005-07-01

    The Frascati Tokamak Upgrade (FTU) is a compact, high-magnetic-field tokamak capable of operating at density and magnetic field values similar to, or even encompassing, those of International Thermonuclear Experimental Reactor (ITER) and therefore provides a unique opportunity to explore physics issues that are directly relevant to ITER. During 2004 the experimental activities were focussed on fully exploiting the lower hybrid system (for generating and controlling the plasma current) and the electron cyclotron heating system (joint experiment with the Institute of Plasma Physics of the National Research Council, Milan). With all four gyrotrons in operation, full electron cyclotron power was achieved up to a record level of 1.5 MW. By simultaneously injecting lower hybrid waves, to tailor the plasma current radial profile, and electron cyclotron waves, to heat the plasma centre, good confinement regimes with internal transport barriers were obtained at the highest plasma density values ever achieved for this operation regime (n {approx}1.5X10{sup 20}m{sup -3}). Specific studies were devoted to optimising the coupling of lower hybrid waves to the plasma (by real-time control of the plasma position) and to generating current by electron cyclotron current drive. The new scanning CO{sub 2} interferometer (developed by the Reversed Field Experiment Consortium) for high spatial and time resolution (1 cm/50 {mu}s) density profile measurements was extensively used. The Thomson scattering diagnostic was upgraded and enabled observation of scattered signals associated with the Confinement background plasma dynamics. As for theoretical studies on the dynamics of turbulence in plasmas, the transition from Bohm-like scaling to gyro-Bohm scaling of the local plasma diffusivity was demonstrated on the basis of a generalised four wave model (joint collaboration with Princeton Plasma Physics Laboratory and the University of California at Irvine). The transition from weak to strong

  16. Magnetic confinement

    International Nuclear Information System (INIS)

    Batistoni, Paola; De Marco, Francesco; Pieroni, Leonardo

    2005-01-01

    The Frascati Tokamak Upgrade (FTU) is a compact, high-magnetic-field tokamak capable of operating at density and magnetic field values similar to, or even encompassing, those of International Thermonuclear Experimental Reactor (ITER) and therefore provides a unique opportunity to explore physics issues that are directly relevant to ITER. During 2004 the experimental activities were focussed on fully exploiting the lower hybrid system (for generating and controlling the plasma current) and the electron cyclotron heating system (joint experiment with the Institute of Plasma Physics of the National Research Council, Milan). With all four gyrotrons in operation, full electron cyclotron power was achieved up to a record level of 1.5 MW. By simultaneously injecting lower hybrid waves, to tailor the plasma current radial profile, and electron cyclotron waves, to heat the plasma centre, good confinement regimes with internal transport barriers were obtained at the highest plasma density values ever achieved for this operation regime (n ∼1.5X10 20 m -3 ). Specific studies were devoted to optimising the coupling of lower hybrid waves to the plasma (by real-time control of the plasma position) and to generating current by electron cyclotron current drive. The new scanning CO 2 interferometer (developed by the Reversed Field Experiment Consortium) for high spatial and time resolution (1 cm/50 μs) density profile measurements was extensively used. The Thomson scattering diagnostic was upgraded and enabled observation of scattered signals associated with the Confinement background plasma dynamics. As for theoretical studies on the dynamics of turbulence in plasmas, the transition from Bohm-like scaling to gyro-Bohm scaling of the local plasma diffusivity was demonstrated on the basis of a generalised four wave model (joint collaboration with Princeton Plasma Physics Laboratory and the University of California at Irvine). The transition from weak to strong energetic particle

  17. Confined placental origin of the circulating cell free fetal DNA revealed by a discordant non-invasive prenatal test result in a trisomy 18 pregnancy.

    Science.gov (United States)

    Mao, Jun; Wang, Ting; Wang, Ben-Jing; Liu, Ying-Hua; Li, Hong; Zhang, Jianguang; Cram, David; Chen, Ying

    2014-06-10

    Non-invasive prenatal testing (NIPT) by massively parallel sequencing is a useful clinical test for the detection of common fetal aneuploidies. While the accuracy of aneuploidy detection can approach 100%, results discordant with the fetus are occasionally reported. In this study we investigated the basis of a discordant T21 positive and T18 negative NIPT result associated with a T18 fetus confirmed by karyotyping. Massively parallel sequencing was used to detect fetal DNA in maternal circulating plasma. The parental origin and nature of the fetal and placental aneuploidies were investigated by quantitative fluorescent PCR of short tandem repeat (STR) sequences and by copy number variation (CNV) sequencing. There was no evidence of T21 maternal mosaicism, T21 microchimerism or a vanishing twin to explain the discordant NIPT result. However, examination of multiple placental biopsies showed both T21 and T18 mosaicism, including one confined region with a significantly higher proportion of T21 cells. Based on fetal DNA fractions and average mosaicism levels, the effective T21 and T18 fetal DNA fractions should have been sufficient for the detection of both trisomies. In this pregnancy, we speculate that confined placental region(s) with higher proportions of T21 cells were preferentially releasing fetal DNAs into the maternal circulation. This study highlights placental mosaicism as a significant risk factor for discordant NIPT results. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Special section containing papers presented at the 13th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (Beijing, China, 17-20 September 2013) Special section containing papers presented at the 13th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (Beijing, China, 17-20 September 2013)

    Science.gov (United States)

    Lin, Z.

    2014-10-01

    In magnetic fusion plasmas, a significant fraction of the kinetic pressure is contributed by superthermal charged particles produced by auxiliary heating (fast ions and electrons) and fusion reactions (a-particles). Since these energetic particles are often far away from thermal equilibrium due to their non-Maxwellian distribution and steep pressure gradients, the free energy can excite electromagnetic instabilities to intensity levels well above the thermal fluctuations. The resultant electromagnetic turbulence could induce large transport of energetic particles, which could reduce heating efficiency, degrade overall plasma confinement, and damage fusion devices. Therefore, understanding and predicting energetic particle confinement properties are critical to the success of burning plasma experiments such as ITER since the ignition relies on plasma self-heating by a-particles. To promote international exchanges and collaborations on energetic particle physics, the biannual conference series under the auspices of the International Atomic Energy Agency (IAEA) were help in Kyiv (1989), Aspenas (1991), Trieste (1993), Princeton (1995), JET/Abingdon (1997), Naka (1999), Gothenburg (2001), San Diego (2003), Takayama (2005), Kloster Seeon (2007), Kyiv (2009), and Austin (2011). The papers in this special section were presented at the most recent meeting, the 13th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems, which was hosted by the Fusion Simulation Center, Peking University, Beijing, China (17-20 September 2013). The program of the meeting consisted of 71 presentations, including 13 invited talks, 26 oral contributed talks, 30 posters, and 2 summary talks, which were selected by the International Advisory Committee (IAC). The IAC members include H. Berk, L.G. Eriksson, A. Fasoli, W. Heidbrink, Ya. Kolesnichenko, Ph. Lauber, Z. Lin, R. Nazikian, S. Pinches, S. Sharapov, K. Shinohara, K. Toi, G. Vlad, and X.T. Ding. The conference program

  19. Preliminary identification of potentially disruptive scenarios at the Greater Confinement Disposal Facility, Area 5 of the Nevada Test Site

    International Nuclear Information System (INIS)

    Guzowski, R.V.; Newman, G.

    1993-12-01

    The Greater Confinement Disposal location is being evaluated to determine whether defense-generated transuranic waste buried at this location complies with the Containment Requirements established by the US Environmental Protection Agency. One step in determining compliance is to identify those combinations of events and processes (scenarios) that define possible future states of the disposal system for which performance assessments must be performed. An established scenario-development procedure was used to identify a comprehensive set of mutually exclusive scenarios. To assure completeness, 761 features, events, processes, and other listings (FEPS) were compiled from 11 references. This number was reduced to 205 primarily through the elimination of duplications. The 205 FEPs were screened based on site-specific, goal-specific, and regulatory criteria. Four events survived screening and were used in preliminary scenario development: (1) exploratory drilling penetrates a GCD borehole, (2) drilling of a withdrawal/injection well penetrates a GCD borehole, (3) subsidence occurs at the RWMS, and (4) irrigation occurs at the RWMS. A logic diagram was used to develop 16 scenarios from the four events. No screening of these scenarios was attempted at this time. Additional screening of the currently retained events and processes will be based on additional data and information from site-characterization activities. When screening of the events and processes is completed, a final set of scenarios will be developed and screened based on consequence and probability of occurrence

  20. Wall Correction Model for Wind Tunnels with Open Test Section

    DEFF Research Database (Denmark)

    Sørensen, Jens Nørkær; Shen, Wen Zhong; Mikkelsen, Robert Flemming

    2004-01-01

    In th paper we present a correction model for wall interference on rotors of wind turbines or propellers in wind tunnels. The model, that is based on a onedimensional momentum approach, is validated against results from CFD computations using a generalized actuator disc principle. Generally......, the corrections from the model are in very good agreement with the CFD computaions, demonstrating that one-dimensional momentum theory is a reliable way of predicting corrections for wall interference in wind tunnels with closed as well as open cross sections. Keywords: Wind tunnel correction, momentum theory...

  1. Comments on confinement criteria

    International Nuclear Information System (INIS)

    Kurak, V.; Schroer, B.; Swieca, J.A.

    1977-01-01

    For a QED 2 model with SU(n) flavour, the nature of the physical states space is more subtle than one expects on the basis of the loop criterion for confinement. One may have colour confinement without confinement of the fundamental flavour representation. Attempts to formulate confinement criteria in which the quark fields play a more fundamental role are discussed [pt

  2. Wall correction model for wind tunnels with open test section

    DEFF Research Database (Denmark)

    Sørensen, Jens Nørkær; Shen, Wen Zhong; Mikkelsen, Robert Flemming

    2006-01-01

    In the paper we present a correction model for wall interference on rotors of wind turbines or propellers in wind tunnels. The model, which is based on a one-dimensional momentum approach, is validated against results from CFD computations using a generalized actuator disc principle. In the model...... the exchange of axial momentum between the tunnel and the ambient room is represented by a simple formula, derived from actuator disc computations. The correction model is validated against Navier-Stokes computations of the flow about a wind turbine rotor. Generally, the corrections from the model are in very...... good agreement with the CFD computations, demonstrating that one-dimensional momentum theory is a reliable way of predicting corrections for wall interference in wind tunnels with closed as well as open cross sections....

  3. Influence of the Golfito earthquake of 30 July 2002 (Mw 6,2) over a pumping test in the confined aquifer in dam site of Pirris Hydroelectric Project

    International Nuclear Information System (INIS)

    Vargas, Asdrubal G.

    2016-01-01

    A pumping test was carry out during 2560 minutes with an average flow rate of 1,9 l/s, using a submersible pump of 5,6 kW, in order to determine the hydrogeological parameters of the fractured confined aquifer founded in the dam site of the Pirris Hydroelectric Power. A significant change in the drawdowns values was observed in four piezometers, approximately 420 minutes after the beginning of the pumping test. This was caused by an earthquake with a magnitude of 6.2 M w with an epicenter near the town of Golfito (133,7 km far away). After the event a recovery of the groundwater level in all piezometers were recorded, although the well continued with the extraction process. Five phases were identified using the recorded level and the time. Phase 1, a drawdown of groundwater level was caused by pumping with a 6-hour period; the second phase was shown a sharp recovery as a result of the earthquake. The third phase was related to stabilization levels after the earthquake, however then a new level recovery phase was occurred due to several aftershocks. Finally another period of small drawdown was presented. After the test the data were reviewed to determine the effect of various parameters. For example partial penetration of the well, and the dip of the aquifer. From this preliminary analysis it was concluded that these factors did not influence the traditional method for the estimation of hydrodynamic parameters, therefore it was decided to analyze the data by the method of Theis and Moench for confined and fractured aquifers respectively. (author) [es

  4. Ductility of reinforced concrete columns confined with stapled strips

    International Nuclear Information System (INIS)

    Tahir, M.F.; Khan, Q.U.Z.; Shabbir, F.; Sharif, M.B.; Ijaz, N.

    2015-01-01

    Response of three 150x150x450mm short reinforced concrete (RC) columns confined with different types of confining steel was investigated. Standard stirrups, strips and stapled strips, each having same cross-sectional area, were employed as confining steel around four comer column bars. Experimental work was aimed at probing into the affect of stapled strip confinement on post elastic behavior and ductility level under cyclic axial load. Ductility ratios, strength enhancement factor and core concrete strengths were compared to study the affect of confinement. Results indicate that strength enhancement in RC columns due to strip and stapled strip confinement was not remarkable as compared to stirrup confined column. It was found that as compared to stirrup confined column, stapled strip confinement enhanced the ductility of RC column by 183% and observed axial capacity of stapled strip confined columns was 41 % higher than the strip confined columns. (author)

  5. Preliminary evaluation of the use of the greater confinement disposal concept for the disposal of Fernald 11e(2) byproduct material at the Nevada Test Site

    International Nuclear Information System (INIS)

    Cochran, J.R.; Brown, T.J.; Stockman, H.W.; Gallegos, D.P.; Conrad, S.H.; Price, L.L.

    1997-09-01

    This report documents a preliminary evaluation of the ability of the greater confinement disposal boreholes at the Nevada Test Site to provide long-term isolation of radionuclides from the disposal of vitrified byproduct material. The byproduct material is essentially concentrated residue from processing uranium ore that contains a complex mixture of radionuclides, many of which are long-lived and present in concentrations greater than 100,000 picoCuries per gram. This material has been stored in three silos at the fernald Environmental Management Project since the early 1950s and will be vitrified into 6,000 yd 3 (4,580 m 3 ) of glass gems prior to disposal. This report documents Sandia National Laboratories' preliminary evaluation for disposal of the byproduct material and includes: the selection of quantitative performance objectives; a conceptual model of the disposal system and the waste; results of the modeling; identified issues, and activities necessary to complete a full performance assessment

  6. Initial progress in the first wall, blanket, and shield Engineering Test Program for magnetically confined fusion-power reactors

    International Nuclear Information System (INIS)

    Herman, H.; Baker, C.C.; Maroni, V.A.

    1981-10-01

    The first wall/blanket/shield (FW/B/S) Engineering Test Program (ETP) progressed from the planning stage into implementation during July, 1981. The program, generic in nature, comprises four Test Program Elements (TPE's), the emphasis of which is on defining the performance parameters for the Fusion Engineering Device (FED) and the major fusion device to follow FED. These elements are: (1) nonnuclear thermal-hydraulic and thermomechanical testing of first wall and component facsimiles with emphasis on surface heat loads and heat transient (i.e., plasma disruption) effects; (2) nonnuclear and nuclear testing of FW/B/S components and assemblies with emphasis on bulk (nuclear) heating effects, integrated FW/B/S hydraulics and mechanics, blanket coolant system transients, and nuclear benchmarks; (3) FW/B/S electromagnetic and eddy current effects testing, including pulsed field penetration, torque and force restraint, electromagnetic materials, liquid metal MHD effects and the like; and (4) FW/B/S Assembly, Maintenance and Repair (AMR) studies focusing on generic AMR criteria, with the objective of preparing an AMR designers guidebook; also, development of rapid remote assembly/disassembly joint system technology, leak detection and remote handling methods

  7. Initial progress in the first wall, blanket, and shield Engineering Test Program for magnetically confined fusion-power reactors

    Energy Technology Data Exchange (ETDEWEB)

    Herman, H.; Baker, C.C.; Maroni, V.A.

    1981-10-01

    The first wall/blanket/shield (FW/B/S) Engineering Test Program (ETP) progressed from the planning stage into implementation during July, 1981. The program, generic in nature, comprises four Test Program Elements (TPE's), the emphasis of which is on defining the performance parameters for the Fusion Engineering Device (FED) and the major fusion device to follow FED. These elements are: (1) nonnuclear thermal-hydraulic and thermomechanical testing of first wall and component facsimiles with emphasis on surface heat loads and heat transient (i.e., plasma disruption) effects; (2) nonnuclear and nuclear testing of FW/B/S components and assemblies with emphasis on bulk (nuclear) heating effects, integrated FW/B/S hydraulics and mechanics, blanket coolant system transients, and nuclear benchmarks; (3) FW/B/S electromagnetic and eddy current effects testing, including pulsed field penetration, torque and force restraint, electromagnetic materials, liquid metal MHD effects and the like; and (4) FW/B/S Assembly, Maintenance and Repair (AMR) studies focusing on generic AMR criteria, with the objective of preparing an AMR designers guidebook; also, development of rapid remote assembly/disassembly joint system technology, leak detection and remote handling methods.

  8. Construction and monitoring of thin overlay and crack sealant test sections at the Pecos test track.

    Science.gov (United States)

    2014-10-01

    In this project, several crack sealant sections were constructed at the Pecos RTC. Six different sealants were : applied in routed and non-routed configurations on both older and newer pavement. The following summer, : the sections were revaluated in...

  9. Development and test of a cryogenic trap system dedicated to confinement of radioactive volatile isotopes in SPIRAL2 post-accelerator

    Science.gov (United States)

    Souli, M.; Dolégiéviez, P.; Fadil, M.; Gallardo, P.; Levallois, R.; Munoz, H.; Ozille, M.; Rouillé, G.; Galet, F.

    2011-12-01

    A cryogenic trap system called Cryotrap has been studied and developed in the framework of nuclear safety studies for SPIRAL2 accelerator. The main objective of Cryotrap is to confine and reduce strongly the migration of radioactive volatile isotopes in beam lines. These radioactive gases are produced after interaction between a deuteron beam and a fissile target. Mainly, Cryotrap is composed by a vacuum vessel and two copper thermal screens maintained separately at two temperatures T1=80 K and T2=20 K. A Cryocooler with two stages at previous temperatures is used to remove static heat losses of the cryostat and ensure an efficient cooling of the system. Due to strong radiological constraints that surround Cryotrap, the coupling system between Cryocooler and thermal screens is based on aluminum thermo-mechanical contraction. The main objective of this original design is to limit direct human maintenance interventions and provide maximum automated operations. A preliminary prototype of Cryotrap has been developed and tested at GANIL laboratory to validate its design, and determine its thermal performance and trapping efficiency. In this paper, we will first introduce briefly SPIRAL2 project and discuss the main role of Cryotrap in nuclear safety of the accelerator. Then, we will describe the proposed conceptual design of Cryotrap and its main characteristics. After that, we will focus on test experiment and analyze experimental data. Finally, we will present preliminary results of gas trapping efficiency tests.

  10. Vertical drop test of a transport fuselage center section including the wheel wells

    Science.gov (United States)

    Williams, M. S.; Hayduk, R. J.

    1983-01-01

    A Boeing 707 fuselage section was drop tested to measure structural, seat, and anthropomorphic dummy response to vertical crash loads. The specimen had nominally zero pitch, roll and yaw at impact with a sink speed of 20 ft/sec. Results from this drop test and other drop tests of different transport sections will be used to prepare for a full-scale crash test of a B-720.

  11. Tool for assistance in testing the safety logic section of nuclear plants

    International Nuclear Information System (INIS)

    Boulc'h, J.; Meur, M. le; Collart, J.M.; Segalard, J.; Uberschlag, J.

    1986-01-01

    The analysis of the protection system logic section (SPIN) of the PALUEL plant performed manually have led to the study of a logical tool for testing the safety logic section having or having not failures. It is a dynamic analyser which from a terminal in a sharing time system will be able to generate testing sequences, to simulate a processor and its environment and to analyse the logic sections with their workable code

  12. Performance assessment of the Greater Confinement Disposal facility on the Nevada Test Site: Comparing the performance of two conceptual site models

    International Nuclear Information System (INIS)

    Baer, T.A.; Price, L.L.; Gallegos, D.P.

    1993-01-01

    A small amount of transuranic (TRU) waste has been disposed of at the Greater Confinement Disposal (GCD) site located on the Nevada Test Site's (NTS) Radioactive Waste Management Site (RWMS). The waste has been buried in several deep (37 m) boreholes dug into the floor of an alluvial basin. For the waste to remain in its current configuration, the DOE must demonstrate compliance of the site with the TRU disposal requirements, 40 CFR 191. Sandia's approach to process modelling in performance assessment is to use demonstrably conservative models of the site. Choosing the most conservative model, however, can be uncertain. As an example, diffusion of contaminants upward from the buried waste in the vadose zone water is the primary mechanism of release. This process can be modelled as straight upward planar diffusion or as spherical diffusion in all directions. The former has high fluxes but low release areas, the latter has lower fluxes but is spread over a greater area. We have developed analytic solutions to a simple test problem for both models and compared the total integrated discharges. The spherical diffusion conceptual model results in at least five times greater release to the accessible environment than the planar model at all diffusivities. Modifying the planar model to allow for a larger release, however, compensated for the smaller original planar discharge and resulted in a new planar model that was more conservative that the spherical model except at low diffusivities

  13. PREFACE: Water in confined geometries

    Science.gov (United States)

    Rovere, Mauro

    2004-11-01

    particularly important to understand whether the glass transition temperature could be experimentally accessible for confined water. In this respect the modifications induced by the confinement on the dynamics of water on supercooling are of extreme interest and a number of experimental and computer simulation studies have been devoted in recent years to this topic. This special section contains papers from different groups which have contributed with various experimental and computer simulation techniques to the progress made in the study of water in confined geometry. I thank all of the authors for their stimulating contributions. I am very pleased in particular that Sow-Hsin Chen agreed to contribute since he has done pioneering experimental work on the dynamical properties of confined water upon supercooling, and he is still very active in the field. The work presented by the group of J Swenson concerns also the glass transition of confined water. The Messina group (Crupi et al) is very active in the study of dynamical properties of confined water and they present their results on water in zeolites. From the experimental side there is also a contribution from J Dore's group, one of the first to perform neutron scattering studies on confined water. The work of J Klein looks at the mobility of water molecules confined in subnanometre films. Important contributions on the computer simulation side come from the Geiger group (Brovchenko et al). They performed very accurate simulations of water in nanopores, exploring a large portion of the phase space. Puibasset et al were able to build a very realistic model to simulate water inside Vycor. Zangi et al review the extensive work performed on confined water. Jedlovszky is an expert on the model potential for water and studied how the hydrogen bond network of water can be modified by the presence of an interface. The special issue is intended to stimulate interest and future work on this important subject.

  14. Liquefaction Mitigation Using Lateral Confinement Technique

    Directory of Open Access Journals (Sweden)

    W. R. Azzam

    2012-01-01

    Full Text Available The exploration of a series of shaking tests on circular model footing with and without cellular confinement constructed around the footing with variable depths and diameters under the effect of variable net bearing stress is studied. The effect of the confinement on the liquefaction time, final settlement, excess pore water pressure, and induced building acceleration were studied. The consequences showed that installing the cell with minimum diameter closer to footing and sufficient penetration depth significantly delayed the liquefaction time. It can be considered as an alternative technique to decrease both the lateral spreading and the final settlement below the foundation during the shaking. The results demonstrated that the cell reduced the excess pore water pressure within the confined zone and the pore water pressure migration outside the confined block where the liquefaction is induced. Moreover, the peak foundation acceleration of the confined footing soil system is reduced compared with the case of without cell confinement.

  15. 25 CFR 141.21 - Trade confined to premises.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Trade confined to premises. 141.21 Section 141.21 Indians... NAVAJO, HOPI AND ZUNI RESERVATIONS General Business Practices § 141.21 Trade confined to premises. The licensee shall confine all trade on the reservation to the premises specified in the license, except, where...

  16. 77 FR 15609 - Revocation of TSCA Section 4 Testing Requirements for Certain High Production Volume Chemical...

    Science.gov (United States)

    2012-03-16

    ... for C.I. Pigment Blue 61, providing a structure- activity relationship (SAR) argument in the test plan... section 4. July 2007. (Document ID number EPA-HQ-OPPT- 2005-0033-0343). 7. Organisation for Economic Co...

  17. Fabrication and Evaluation of Welded Ti-6Al-4V Test Sections

    National Research Council Canada - National Science Library

    Grendahl, Scott

    2001-01-01

    ... material for the Ml Abrams turret glacis as opposed to the presently utilized RHA steel. Two turret glacis test sections were fabricated from Ti-6A1-4V armor plate, and one was fabricated from RHA steel...

  18. CFRMF spectrum update and application to dosimeter cross-section data testing

    International Nuclear Information System (INIS)

    Anderl, R.A.; Harker, Y.D.; Millsap, D.A.; Rogers, J.W.; Ryskamp, J.M.

    1982-01-01

    The Coupled Fast Reactivity Measurements Facility (CFRMF) at the Idaho National Engineering Laboratory (INEL) is a Cross Section Evaluation Working Group (CSEWG) benchmark for data testing of dosimetry, fission-product and actinide cross sections important to fast-reactor technology. In this paper we present the results of our work in updating the CFRMF spectrum characterization and in applying CFRMF integral data to testing ENDF/B-V dosimeter cross sections. Updated characterization of the central neutron spectrum includes the results of neutronics calculations with ENDF/B-V nuclear data, the generation of a fine-group spectrum representation for integral data-testing applications, and a sensitivity and uncertainty analysis which provides a flux-spectrum covariance matrix related to uncertainties and correlations in the nuclear data used in a neutronics calculation. Our application of CFRMF integral data to cross section testing has included both conventional integral testing analyses and least-squares-adjustment analyses with the FERRET code. The conventional integral data-testing analysis, based on C/E ratios, indicates discrepancies outside the estimated integral test uncertainty for the 6 Li(n,He), 10 B(n,He), 47 Ti(n,p), 58 Fe(n,γ), 197 Au(n,γ) and 232 Th(n,γ) cross sections. The integral test uncertainty included contributions from the measured integral data and from the spectrum and cross sections used to obtain the calculated integral data. Within the uncertainty and correlation specifications for the input spectrum and dosimeter cross sections, the least-squares-adjustment analysis indicated a high degree of consistency between the measured integral data and the ENDF/B-V dosimeter cross sections for all reactions except 10 B

  19. Tokamak confinement scaling laws

    International Nuclear Information System (INIS)

    Connor, J.

    1998-01-01

    The scaling of energy confinement with engineering parameters, such as plasma current and major radius, is important for establishing the size of an ignited fusion device. Tokamaks exhibit a variety of modes of operation with different confinement properties. At present there is no adequate first principles theory to predict tokamak energy confinement and the empirical scaling method is the preferred approach to designing next step tokamaks. This paper reviews a number of robust theoretical concepts, such as dimensional analysis and stability boundaries, which provide a framework for characterising and understanding tokamak confinement and, therefore, generate more confidence in using empirical laws for extrapolation to future devices. (author)

  20. Confinement and the safety factor profile

    Energy Technology Data Exchange (ETDEWEB)

    Batha, S.H.; Levinton, F.M. [Fusion Physics and Technology, Torrance, CA (United States); Scott, S.D. [Princeton Univ., NJ (United States). Plasma Physics Lab.] [and others

    1995-12-01

    The conjecture that the safety factor profile, q(r), controls the improvement in tokamak plasmas from poor confinement in the Low (L-) mode regime to improved confinement in the supershot regime has been tested in two experiments on the Tokamak Fusion Test Reactor (TFTR). First, helium was puffed into the beam-heated phase of a supershot discharge which induced a degradation from supershot to L-mode confinement in about 100 msec, far less than the current relaxation time. The q and shear profiles measured by a motional Stark effect polarimeter showed little change during the confinement degradation. Second, rapid current ramps in supershot plasmas altered the q profile, but were observed not to change significantly the energy confinement. Thus, enhanced confinement in supershot plasmas is not due to a particular q profile which has enhanced stability or transport properties. The discharges making a continuous transition between supershot and L-mode confinement were also used to test the critical-electron-temperature-gradient transport model. It was found that this model could not reproduce the large changes in electron and ion temperature caused by the change in confinement.

  1. On the implications of confinement

    International Nuclear Information System (INIS)

    Roberts, C.D.

    1992-01-01

    In this paper, the authors consider some implications of confinement starting from the basic observation that cross-sections for the production of colored asymptotic states, such as free quarks and gluons, from color singlet initial states must be zero if QCD is to be confining. The authors discuss two pictures of confinement: the failure of the cluster decomposition property and the absence of a pole at timelike momenta in the propagator of a confined particle. The authors use QCD-based models as a framework to relate the failure of the cluster decomposition property to other ideas, such as the role of a nonzero gluon condensate. The authors' primary interest is to address the question of the absence of a mass pole through a study of model Schwinger-Dyson equations. These equations contain some of the dynamical information that is present in the study of the cluster decomposition property. The authors discuss the problems within this idea and its study using the Schwinger-Dyson equations

  2. New Tools to Prepare ACE Cross-section Files for MCNP Analytic Test Problems

    International Nuclear Information System (INIS)

    Brown, Forrest B.

    2016-01-01

    Monte Carlo calculations using one-group cross sections, multigroup cross sections, or simple continuous energy cross sections are often used to: (1) verify production codes against known analytical solutions, (2) verify new methods and algorithms that do not involve detailed collision physics, (3) compare Monte Carlo calculation methods with deterministic methods, and (4) teach fundamentals to students. In this work we describe 2 new tools for preparing the ACE cross-section files to be used by MCNP ® for these analytic test problems, simple a ce.pl and simple a ce m g.pl.

  3. Vertical Drop Test of a YS-11 Fuselage Section (Part 2)

    Science.gov (United States)

    Iwasaki, Kazuo; Kumakura, Ikuo; Minegishi, Masakutsu; Shoji, Hirokazu; Yoshimoto, Norio; Miyaki, Hiromitsu; Terada, Hiroyuki; Isoe, Akira; Yamaoka, Toshihiro; Katayama, Noriaki; Hayashi, Toru; Akaso, Tetsuya; Kosaka, Hideyuki

    The Structures and Materials Research Center of the National Aerospace Laboratory of Japan (NAL) and Kawasaki Heavy Industries, Ltd. (KHI) conducted the 2nd vertical drop test of a fuselage section cut from a NAMC YS-11 transport airplane in July 2002. The main objective of this test program was to obtain background data for aircraft cabin safety by drop test of a full-scale fuselage section and to develop computational tool for crash simulation of aircraft fuselage structure. The test article including seats and anthropomorphic test dummies was dropped to a rigid impact surface by free-fall method at a velocity of 7.6m/s (25ft/s). The impact environment and the resultant response of the fuselage structure and the passenger dummies were considered to be severe but potentially survivable. A description of the results of the 1st drop test and the 2nd drop test is presented in this paper.

  4. Placement of Smart Grass reinforcement at test sections Groningen Sea dike

    NARCIS (Netherlands)

    Verhagen, H.J.; van Gerven, K.A.J.; Akkerman, G.J.

    2007-01-01

    The present report deals with the application of a provisional Smart Grass Reinforcement (SGR) system in 2006 for full scale testing of increased overtopping at the Groningen sea dyke test section near Delfzijl, as envisaged in 2007. The SGR has been placed at two strips of 4 m wide: one primary

  5. Mixed Waste Management Facility (MWMF) closure, Savannah River Plant: Clay cap test section construction report

    Energy Technology Data Exchange (ETDEWEB)

    1988-02-26

    This report contains appendices 3 through 6 for the Clay Cap Test Section Construction Report for the Mixed Waste Management Facility (MWMF) closure at the Savannah River Plant. The Clay Cap Test Program was conducted to evaluate the source, lab. permeability, in-situ permeability, and compaction characteristics, representative of kaolin clays from the Aiken, South Carolina vicinity. (KJD)

  6. Crash Simulation of a Boeing 737 Fuselage Section Vertical Drop Test

    Science.gov (United States)

    Fasanella, Edwin L.; Jackson, Karen E.; Jones, Yvonne T.; Frings, Gary; Vu, Tong

    2004-01-01

    A 30-ft/s vertical drop test of a fuselage section of a Boeing 737 aircraft was conducted in October of 1999 at the FAA Technical Center in Atlantic City, NJ. This test was performed to evaluate the structural integrity of a conformable auxiliary fuel tank mounted beneath the floor and to determine its effect on the impact response of the airframe structure and the occupants. The test data were used to compare with a finite element simulation of the fuselage structure and to gain a better understanding of the impact physics through analytical/experimental correlation. To perform this simulation, a full-scale 3-dimensional finite element model of the fuselage section was developed using the explicit, nonlinear transient-dynamic finite element code, MSC.Dytran. The emphasis of the simulation was to predict the structural deformation and floor-level acceleration responses obtained from the drop test of the B737 fuselage section with the auxiliary fuel tank.

  7. Finite Element Simulations of Two Vertical Drop Tests of F-28 Fuselage Sections

    Science.gov (United States)

    Jackson, Karen E.; Littell, Justin D.; Annett, Martin S.; Haskin, Ian M.

    2018-01-01

    In March 2017, a vertical drop test of a forward fuselage section of a Fokker F-28 MK4000 aircraft was conducted as part of a joint NASA/FAA project to investigate the performance of transport aircraft under realistic crash conditions. In June 2017, a vertical drop test was conducted of a wing-box fuselage section of the same aircraft. Both sections were configured with two rows of aircraft seats, in a triple-double configuration. A total of ten Anthropomorphic Test Devices (ATDs) were secured in seats using standard lap belt restraints. The forward fuselage section was also configured with luggage in the cargo hold. Both sections were outfitted with two hat racks, each with added ballast mass. The drop tests were performed at the Landing and Impact Research facility located at NASA Langley Research Center in Hampton, Virginia. The measured impact velocity for the forward fuselage section was 346.8-in/s onto soil. The wing-box section was dropped with a downward facing pitch angle onto a sloping soil surface in order to create an induced forward acceleration in the airframe. The vertical impact velocity of the wing-box section was 349.2-in/s. A second objective of this project was to assess the capabilities of finite element simulations to predict the test responses. Finite element models of both fuselage sections were developed for execution in LS-DYNA(Registered Trademark), a commercial explicit nonlinear transient dynamic code. The models contained accurate representations of the airframe structure, the hat racks and hat rack masses, the floor and seat tracks, the luggage in the cargo hold for the forward section, and the detailed under-floor structure in the wing-box section. Initially, concentrated masses were used to represent the inertial properties of the seats, restraints, and ATD occupants. However, later simulations were performed that included finite element representations of the seats, restraints, and ATD occupants. These models were developed to more

  8. Dynamics in geometrical confinement

    CERN Document Server

    Kremer, Friedrich

    2014-01-01

    This book describes the dynamics of low molecular weight and polymeric molecules when they are constrained under conditions of geometrical confinement. It covers geometrical confinement in different dimensionalities: (i) in nanometer thin layers or self supporting films (1-dimensional confinement) (ii) in pores or tubes with nanometric diameters (2-dimensional confinement) (iii) as micelles embedded in matrices (3-dimensional) or as nanodroplets.The dynamics under such conditions have been a much discussed and central topic in the focus of intense worldwide research activities within the last two decades. The present book discusses how the resulting molecular mobility is influenced by the subtle counterbalance between surface effects (typically slowing down molecular dynamics through attractive guest/host interactions) and confinement effects (typically increasing the mobility). It also explains how these influences can be modified and tuned, e.g. through appropriate surface coatings, film thicknesses or pore...

  9. Elastic membranes in confinement.

    Science.gov (United States)

    Bostwick, J B; Miksis, M J; Davis, S H

    2016-07-01

    An elastic membrane stretched between two walls takes a shape defined by its length and the volume of fluid it encloses. Many biological structures, such as cells, mitochondria and coiled DNA, have fine internal structure in which a membrane (or elastic member) is geometrically 'confined' by another object. Here, the two-dimensional shape of an elastic membrane in a 'confining' box is studied by introducing a repulsive confinement pressure that prevents the membrane from intersecting the wall. The stage is set by contrasting confined and unconfined solutions. Continuation methods are then used to compute response diagrams, from which we identify the particular membrane mechanics that generate mitochondria-like shapes. Large confinement pressures yield complex response diagrams with secondary bifurcations and multiple turning points where modal identities may change. Regions in parameter space where such behaviour occurs are then mapped. © 2016 The Author(s).

  10. FRP confined smart concrete/mortar

    Science.gov (United States)

    Xiao, Y.; Zhu, P. S.; Choi, K. G.; Wu, Y. T.; Huang, Z. Y.; Shan, B.

    2006-03-01

    In this study, fiber reinforced polymer (FRP) confined smart concrete/mortar sensors were invented and validated for significantly improved measurement range. Several trial mixes were made using cement mortar and micron-phase graphite powders at different mix proportions. Compressive loading tests were conducted on smart mortar cylinder specimens with or without FRP confinement. Two-probe method was used to detect the electrical resistance of the smart cement mortar specimens. Strong correlation was recognized between the stress and electric resistance of the smart mortar. The test results indicated that the FRP wrapping could significantly enlarge the range of such self-sensing property as a consequence of confinement.

  11. Confinement optimisation by plasma shaping on TCV

    International Nuclear Information System (INIS)

    Moret, J.M.; Behn, R.; Franke, S.; Hofmann, F.; Weisen, H.

    1997-01-01

    Any improvement in the energy confinement time of a tokamak reactor may facilitate its access to ignition. TCV has the unique capability of creating a wide variety of plasma shapes and can therefore investigate to which extent an appropriate choice of the plasma shape can improve the energy confinement time. For simple shapes defined only by their elongation and triangularity, it has already been observed on TCV that the confinement properties of the plasma depend strongly on the shape. This previous work has now been extended to include more complex shapes and higher elongations, in order firstly to test the applicability of the previously proposed explanation for the shape dependence of the confinement time and secondly to propose new shapes which offer a substantial gain on their confinement characteristics. (author) 4 figs., 1 tab., 2 refs

  12. Predictions of a theory of quark confinement

    International Nuclear Information System (INIS)

    Mack, G.

    1980-03-01

    We propose a theory of quark confinement which uses only the simplest of approximations. It explains persistence of quark confinement in Yang Mills theories with gauge group SU(2) or SU(3) as a consequence of asymptotic freedom in perturbation theory and of the known phase structure of Z(2) resp. Z(3) lattice gauge theory. Predictions are derived which can in principle be tested by computer simulation. Some are already tested by results of Creutz. They are in good agreement. (orig.)

  13. Equilibrium quality and mass flux distributions in an adiabatic three-subchannel test section

    International Nuclear Information System (INIS)

    Yadigaroglu, G.; Maganas, A.

    1993-01-01

    An experiment was designed to measure the fully-developed quality and mass flux distributions in an adiabatic three-subchannel test section. The three subchannels had the geometrical characteristics of the corner, side, and interior subchannels of a BWR-5 rod bundle. Data collected with Refrigerant-144 at pressures ranging from 7 to 14 bar, simulating operation with water in the range 55 to 103 bar are reported. The average mass flux and quality in the test section were in the ranges 1300 to 1750 kg/m s and -0.03 to 0.25, respectively. The data are analyzed and presented in various forms

  14. The confinement problem

    International Nuclear Information System (INIS)

    Seiler, E.

    1985-01-01

    Confinement of quarks is sometimes taken as some kind of dogma in the contemporary theory of strong interactions - quantum chromo-dynamics (QCD). Scientists should not be content with that. What is meant by ''permanent confinement'' should be formulated more precisely to see whether the theory has this property or not. The author looks at some possible interpretations of ''confinement'' and their shortcomings and then turns to the most widely used rather pragmatic definition based on the somewhat unphysical notion of infinitely heavy external sources. He describes what is known about the problem and tries to bring into focus some aspects that are insufficiently understood in his opinion

  15. Strength tests of cold-formed channel sections undergoing local and distortional buckling

    Science.gov (United States)

    Kwon, Y. B.; Hancock, G. J.

    1991-06-01

    In this report, the results of compression tests of thin-walled channel section columns formed by brake-precessing are described. Two different section geometries, a simple lipped channel and a lipped channel with an intermediate stiffener in the web, were tested between fixed-ended boundary conditions. The geometries and yield strength were chosen to ensure that a substantial post-buckling strength reserve occurred in the distortional mode and that local buckling might occur simultaneously at a shorter wavelength. The deformations were measured using a movable frame on which linear displacement transducers were mounted. The residual stresses and material properties were also measured. Distortional or mixed local distortional buckling stresses obtained from testing are compared with theoretical buckling stresses. Design curves for the maximum strength of the columns undergoing distortional or mixed modes of buckling are proposed and compared with the test results.

  16. Determining the Efficiency of Different Preoperative Difficult Intubation Tests on Patients Undergoing Caesarean Section.

    Science.gov (United States)

    Yıldırım, İlker; İnal, Mehmet Turan; Memiş, Dilek; Turan, F Nesrin

    2017-09-29

    Pregnancy-induced anatomical and physiological changes in the airway make airway management difficult in obstetric patients; thus, preoperative evaluation of the airway is important for obstetric patients. To determine the effectiveness of the modified Mallampati test; the interincisor, sternomental and thyromental distances and the upper limb bite test. The second aim was to assess the effectiveness of the combination of the upper limb bite test with the other tests in obstetric patients. Cross-sectional study. Pregnant women (n=250) scheduled for caesarean section were analysed. The patients' ages, heights and weights were collected. Preoperative airway evaluation was done by using a modified version of the Mallampati test. The interincisor, sternomental and thyromental distances were measured, and the upper limb bite test was performed. The laryngoscopy difficulty was evaluated by using Cormack-Lehane classification. No statistically significant differences were found between groups in age, height or weight (p>0.05). The modified Mallampati test and interincisor, sternomental and thyromental distances revealed a lower number of easy intubations than that determined by the Cormack-Lehane classification and a higher number of difficult intubations than the actual number of cases (p<0.05). The sensitivity and specificity of the modified Mallampati test, the upper limb bite test, the interincisor distance test and the sternomental and thyromental distance tests were found to be 73.08, 57.69, 84.62, 80.77 and 88.46 and 90.62, 99.11, 83.04, 84.37 and 87.05, respectively. When the combinations were examined, the sensitivity and specificity of the combination of the upper limb bite test with the modified Mallampati test were found to be 57.69 and 100, respectively. When the upper limb bite test was combined with the interincisor distance, the sensitivity and specificity were 46.15 and 100, respectively. We found a sensitivity and specificity of 93.75 and 95

  17. Determining the Efficiency of Different Preoperative Difficult Intubation Tests on Patients Undergoing Caesarean Section

    Directory of Open Access Journals (Sweden)

    İlker Yıldırım

    2017-10-01

    Full Text Available Background: Pregnancy-induced anatomical and physiological changes in the airway make airway management difficult in obstetric patients; thus, preoperative evaluation of the airway is important for obstetric patients. Aims: To determine the effectiveness of the modified Mallampati test; the interincisor, sternomental and thyromental distances and the upper limb bite test. The second aim was to assess the effectiveness of the combination of the upper limb bite test with the other tests in obstetric patients. Study Design: Cross-sectional study. Methods: Pregnant women (n=250 scheduled for caesarean section were analysed. The patients" ages, heights and weights were collected. Preoperative airway evaluation was done by using a modified version of the Mallampati test. The interincisor, sternomental and thyromental distances were measured, and the upper limb bite test was performed. The laryngoscopy difficulty was evaluated by using Cormack-Lehane classification. Results: No statistically significant differences were found between groups in age, height or weight (p>0.05. The modified Mallampati test and interincisor, sternomental and thyromental distances revealed a lower number of easy intubations than that determined by the Cormack-Lehane classification and a higher number of difficult intubations than the actual number of cases (p<0.05. The sensitivity and specificity of the modified Mallampati test, the upper limb bite test, the interincisor distance test and the sternomental and thyromental distance tests were found to be 73.08, 57.69, 84.62, 80.77 and 88.46 and 90.62, 99.11, 83.04, 84.37 and 87.05, respectively. When the combinations were examined, the sensitivity and specificity of the combination of the upper limb bite test with the modified Mallampati test were found to be 57.69 and 100, respectively. When the upper limb bite test was combined with the interincisor distance, the sensitivity and specificity were 46.15 and 100, respectively

  18. Water Impact Test and Simulation of a Composite Energy Absorbing Fuselage Section

    Science.gov (United States)

    Fasanella, Edwin L.; Jackson, Karen E.; Sparks, Chad; Sareen, Ashish

    2003-01-01

    In March 2002, a 25-ft/s vertical drop test of a composite fuselage section was conducted onto water. The purpose of the test was to obtain experimental data characterizing the structural response of the fuselage section during water impact for comparison with two previous drop tests that were performed onto a rigid surface and soft soil. For the drop test, the fuselage section was configured with ten 100-lb. lead masses, five per side, that were attached to seat rails mounted to the floor. The fuselage section was raised to a height of 10-ft. and dropped vertically into a 15-ft. diameter pool filled to a depth of 3.5-ft. with water. Approximately 70 channels of data were collected during the drop test at a 10-kHz sampling rate. The test data were used to validate crash simulations of the water impact that were developed using the nonlinear, explicit transient dynamic codes, MSC.Dytran and LS-DYNA. The fuselage structure was modeled using shell and solid elements with a Lagrangian mesh, and the water was modeled with both Eulerian and Lagrangian techniques. The fluid-structure interactions were executed using the fast general coupling in MSC.Dytran and the Arbitrary Lagrange-Euler (ALE) coupling in LS-DYNA. Additionally, the smooth particle hydrodynamics (SPH) meshless Lagrangian technique was used in LS-DYNA to represent the fluid. The simulation results were correlated with the test data to validate the modeling approach. Additional simulation studies were performed to determine how changes in mesh density, mesh uniformity, fluid viscosity, and failure strain influence the test-analysis correlation.

  19. BY FRUSTUM CONFINING VESSEL

    Directory of Open Access Journals (Sweden)

    Javad Khazaei

    2016-09-01

    Full Text Available Helical piles are environmentally friendly and economical deep foundations that, due to environmental considerations, are excellent additions to a variety of deep foundation alternatives available to the practitioner. Helical piles performance depends on soil properties, the pile geometry and soil-pile interaction. Helical piles can be a proper alternative in sensitive environmental sites if their bearing capacity is sufficient to support applied loads. The failure capacity of helical piles in this study was measured via an experimental research program that was carried out by Frustum Confining Vessel (FCV. FCV is a frustum chamber by approximately linear increase in vertical and lateral stresses along depth from top to bottom. Due to special geometry and applied bottom pressure, this apparatus is a proper choice to test small model piles which can simulate field stress conditions. Small scale helical piles are made with either single helix or more helixes and installed in fine grained sand with three various densities. Axial loading tests including compression and tension tests were performed to achieve pile ultimate capacity. The results indicate the helical piles behavior depends essentially on pile geometric characteristics, i.e. helix configuration and soil properties. According to the achievements, axial uplift capacity of helical model piles is about equal to usual steel model piles that have the helixes diameter. Helical pile compression bearing capacity is too sufficient to act as a medium pile, thus it can be substituted other piles in special geoenvironmental conditions. The bearing capacity also depends on spacing ratio, S/D, and helixes diameter.

  20. The confining trailing string

    CERN Document Server

    Kiritsis, E; Nitti, F

    2014-01-01

    We extend the holographic trailing string picture of a heavy quark to the case of a bulk geometry dual to a confining gauge theory. We compute the classical trailing confining string solution for a static as well as a uniformly moving quark. The trailing string is infinitely extended and approaches a confining horizon, situated at a critical value of the radial coordinate, along one of the space-time directions, breaking boundary rotational invariance. We compute the equations for the fluctuations around the classical solutions, which are used to obtain boundary force correlators controlling the Langevin dynamics of the quark. The imaginary part of the correlators has a non-trivial low-frequency limit, which gives rise to a viscous friction coefficient induced by the confining vacuum. The vacuum correlators are used to define finite-temperature dressed Langevin correlators with an appropriate high-frequency behavior.

  1. The confining trailing string

    Energy Technology Data Exchange (ETDEWEB)

    Kiritsis, Elias [APC, Université Paris 7, CNRS/IN2P3, CEA/IRFU, Obs. de Paris, Sorbonne Paris Cité,Bâtiment Condorcet, F-75205, Paris Cedex 13 (UMR du CNRS 7164) (France); Theory Group, Physics Department, CERN,CH-1211, Geneva 23 (Switzerland); Crete Center for Theoretical Physics, Department of Physics, University of Crete,71003 Heraklion (Greece); Mazzanti, Liuba [Institute for Theoretical Physics and Spinoza Institute, Utrecht University,3508 TD Utrecht (Netherlands); Nitti, Francesco [APC, Université Paris 7, CNRS/IN2P3, CEA/IRFU, Obs. de Paris, Sorbonne Paris Cité,Bâtiment Condorcet, F-75205, Paris Cedex 13 (UMR du CNRS 7164) (France)

    2014-02-19

    We extend the holographic trailing string picture of a heavy quark to the case of a bulk geometry dual to a confining gauge theory. We compute the classical trailing confining string solution for a static as well as a uniformly moving quark. The trailing string is infinitely extended and approaches a confining horizon, situated at a critical value of the radial coordinate, along one of the space-time directions, breaking boundary rotational invariance. We compute the equations for the fluctuations around the classical solutions, which are used to obtain boundary force correlators controlling the Langevin dynamics of the quark. The imaginary part of the correlators has a non-trivial low-frequency limit, which gives rise to a viscous friction coefficient induced by the confining vacuum. The vacuum correlators are used to define finite-temperature dressed Langevin correlators with an appropriate high-frequency behavior.

  2. Solitons and confinement

    International Nuclear Information System (INIS)

    Swieca, J.A.

    1976-01-01

    Some aspects of two recent developments in quantum field theory are discussed. First, related with 'extended particles' such as soliton, kink and the 't Hooft monopole. Second, with confinement of particles which are realized in the Schwinger model [pt

  3. The cryogenic pumping section of KATRIN and the test experiment TRAP

    CERN Document Server

    Eichelhardt, F

    2011-01-01

    The Karlsruhe Tritium Neutrino experiment (KATRIN) employs a Cryogenic Pumping Section (CPS) at ~ 4.5 K to suppress the tritium penetration into the spectrometers. A test experiment (TRAP - Tritium Argon frost Pump) has been set up to investigate the tritium pumping performance of the CPS.

  4. Experimental Investigation of Tensile Test on Connection of Cold-formed Cut-curved Steel Section

    Science.gov (United States)

    Sani, Mohd Syahrul Hisyam Mohd; Muftah, Fadhluhartini; Rahman, Nurul Farraheeda Abdul; Fakri Muda, Mohd

    2017-08-01

    Cold-formed steel (CFS) is widely used as structural and non-structural components such as roof trusses and purlin. A CFS channel section with double intermediate web stiffener and lipped is chosen based on the broader usage in roof truss construction. CFS section is cut to form cold-formed pre-cut-curved steel section and lastly strengthened by several types of method or likely known as connection to establish the cold-formed cut-curved steel (CFCCS) section. CFCCS is proposed to be used as a top chord section in the roof truss system. The CFCCS is to resist the buckling phenomena of the roof truss structure and reduced the compression effect on the top chord. The tensile test connection of CFCCS section, especially at the flange element with eight types of connection by welding, plate with self-drilling screw and combination is investigated. The flange element is the weakest part that must be solved first other than the web element because they are being cut totally, 100% of their length for curving process. The testing is done using a universal testing machine for a tensile load. From the experiment, specimen with full welding has shown as a good result with an ultimate load of 13.37 kN and reported having 35.41% when compared with normal specimen without any of connection methods. Furthermore, the experimental result is distinguished by using Eurocode 3. The failure of a full welding specimen is due to breaking at the welding location. Additionally, all specimens with either full weld or spot weld or combination failed due to breaking on weld connection, but specimen with flange plate and self-drilling screw failed due to tilting and bearing. Finally, the full welding specimen is chosen as a good connection to perform the strengthening method of CFCCS section.

  5. Fusion, magnetic confinement

    Energy Technology Data Exchange (ETDEWEB)

    Berk, H.L.

    1992-08-06

    An overview is presented of the principles of magnetic confinement of plasmas for the purpose of achieving controlled fusion conditions. Sec. 1 discusses the different nuclear fusion reactions which can be exploited in prospective fusion reactors and explains why special technologies need to be developed for the supply of tritium or {sup 3}He, the probable fuels. In Sec. 2 the Lawson condition, a criterion that is a measure of the quality of confinement relative to achieving fusion conditions, is explained. In Sec. 3 fluid equations are used to describe plasma confinement. Specific confinement configurations are considered. In Sec. 4 the orbits of particle sin magneti and electric fields are discussed. In Sec. 5 stability considerations are discussed. It is noted that confinement systems usually need to satisfy stability constraints imposed by ideal magnetohydrodynamic (MHD) theory. The paper culminates with a summary of experimental progress in magnetic confinement. Present experiments in tokamaks have reached the point that the conditions necessary to achieve fusion are being satisfied.

  6. Plasma confinement in a magnetic dipole

    International Nuclear Information System (INIS)

    Kesner, J.; Bromberg, L.; Garnier, D.; Mauel, M.

    2001-01-01

    A dipole fusion confinement device is stable to MHD interchange and ballooning modes when the pressure profile is sufficiently gentle. The plasma can be confined at high beta, is steady state and disruption free. Theory indicates that when the pressure gradient is sufficiently gentle to satisfy MHD requirements drift waves will also be stable. The dipole approach is particularly applicable for advanced fuels. A new experimental facility is presently being built to test the stability and transport properties of a dipole-confined plasma. (author)

  7. Plasma confinement in a magnetic dipole

    International Nuclear Information System (INIS)

    Kesner, J.; Bromberg, L.; Garnier, D.; Mauel, M.

    1999-01-01

    A dipole fusion confinement device is stable to MHD interchange and ballooning modes when the pressure profile is sufficiently gentle. The plasma can be confined at high beta, is steady state and disruption free. Theory indicates that when the pressure gradient is sufficiently gentle to satisfy MHD requirements drift waves will also be stable. The dipole approach is particularly applicable for advanced fuels. A new experimental facility is presently being built to test the stability and transport properties of a dipole-confined plasma. (author)

  8. Drop test and crash simulation of a civil airplane fuselage section

    Directory of Open Access Journals (Sweden)

    Liu Xiaochuan

    2015-04-01

    Full Text Available Crashworthiness of a civil airplane fuselage section was studied in this paper. Firstly, the failure criterion of a rivet was studied by test, showing that the ultimate tension and shear failure loads were obviously affected by the loading speed. The relations between the loading speed and the average ultimate shear, tension loads were expressed by two logarithmic functions. Then, a vertical drop test of a civil airplane fuselage section was conducted with an actual impact velocity of 6.85 m/s, meanwhile the deformation of cabin frame and the accelerations at typical locations were measured. The finite element model of a main fuselage structure was developed and validated by modal test, and the error between the calculated frequencies and the test ones of the first four modes were less than 5%. Numerical simulation of the drop test was performed by using the LS-DYNA code and the simulation results show a good agreement with that of drop test. Deforming mode of the analysis was the same as the drop test; the maximum average rigid acceleration in test was 8.81g while the calculated one was 9.17g, with an error of 4.1%; average maximum test deformation at four points on the front cabin floor was 420 mm, while the calculated one was 406 mm, with an error of 3.2%; the peak value of the calculated acceleration at a typical location was 14.72g, which is lower than the test result by 5.46%; the calculated rebound velocity result was greater than the test result 17.8% and energy absorption duration was longer than the test result by 5.73%.

  9. The design and development of an acoustic test section for the ARA transonic wind tunnel

    Science.gov (United States)

    Wood, M. E.; Newman, D. A.

    1988-11-01

    The structural, aerodynamic and acoustic design of a lined test section necessary to produce a sufficiently reflection-free environment for noise tests in the Aircraft Research Association (ARA) tunnel at Mach numbers up to 0.85 are described. The aerodynamic design was aided by computational fluid dynamics methods and the acoustic design by a ray-theory model. Results of the aerodynamic calibration of the liner and preliminary acoustic and performance tests on two model propellers are presented. Development work carried out to improve the liner acoustically and aerodynamically is described.

  10. How do people respond to self-test results? A cross-sectional survey

    Directory of Open Access Journals (Sweden)

    de Vries Nanne K

    2010-10-01

    Full Text Available Abstract Background Self-tests, tests on medical conditions that can be performed by consumers without consulting a doctor first, are frequently used. Nevertheless, there are concerns about the safety of self-testing, as it may delay diagnosis and appropriate treatment in the case of inappropriate use of the test, or false-negative results. It is unclear whether self-tests stimulate appropriate follow-up behaviour. Our aim was to examine the frequency of self-test use, consumers' response to self-test results in terms of their confidence in the result, reassurance by the test result, and follow-up behaviour. Methods A two step cross-sectional survey was designed. A random sample of 6700 Internet users in an existing Internet panel received an online questionnaire on the use of self-tests. Self-tests were defined as tests on body materials, initiated by consumers with the aim to diagnose a disease or risk factor. A second questionnaire on consumers' response to self-test results was sent to the respondents that were identified as a self-tester in the first questionnaire (n = 703. Results 18.1% (799/4416 of the respondents had ever performed a self-test, the most frequently used tests being those for diabetes (5.3%, kidney disease (4.9%, cholesterol (4.5%, urinary tract infection (1.9% and HIV/AIDS and Chlamydia (both 1.6%. A total of 78.1% of the testers with a normal test result and 81.4% of those with an abnormal result reported confidence in this result. Almost all (95.6% of the testers with a normal result felt reassured. After a normal result, 78.1% did not take any further action and 5.8% consulted a doctor. The corresponding figures after an abnormal test result were 9.3% and 72.2%, respectively. Conclusions Respondents who had performed a self-test seemed to base their follow-up behaviour on the result of the test. They had confidence in the test result, and were often reassured by a normal result. After an abnormal result, most self

  11. Benchmark experiments to test plutonium and stainless steel cross sections. Topical report

    International Nuclear Information System (INIS)

    Jenquin, U.P.; Bierman, S.R.

    1978-06-01

    The Nuclear Regulatory Commission (NRC) commissioned Battelle, Pacific Northwest Laboratory (PNL) to ascertain the accuracy of the neutron cross sections for the isotopes of plutonium and the constituents of stainless steel and determine if improvements can be made in application to criticality safety analysis. NRC's particular area of interest is in the transportation of light-water reactor spent fuel assemblies. The project was divided into two tasks. The first task was to define a set of integral experimental measurements (benchmarks). The second task is to use these benchmarks in neutronics calculations such that the accuracy of ENDF/B-IV plutonium and stainless steel cross sections can be assessed. The results of the first task are given in this report. A set of integral experiments most pertinent to testing the cross sections has been identified and the code input data for calculating each experiment has been developed

  12. Equilibrium quality and mass flux distributions in an adiabatic three-subchannel test section

    International Nuclear Information System (INIS)

    Yadigaroglu, G.; Maganas, A.

    1995-01-01

    An experiment was designed to measure the fully developed quality and mass flux distributions in an adiabatic three-subchannel test section. The three subchannels had the geometrical characteristics of the corner, side, and interior subchannels of a boiling water reactor (BWR-5) rod bundle. Data collected with Refrigerant-114 at pressures ranging from 7 to 14 bars, simulating operation with water in the range 55 to 103 bars are reported. The average mass flux and quality in the test section were in the ranges 1,300 to 1,750 kg/m 2 · s and -0.03 to 0.25, respectively. The data are analyzed and presented in various forms

  13. Analysis for transient temperature distribution two phase flow using test section QUEEN-02

    International Nuclear Information System (INIS)

    Ainur Rosidi; Joko Prasetio; Edy Sumarno; Kiswanta; Heru Bambang

    2013-01-01

    Experiments on the transient temperature distribution using a two-phase flow test facility QUEEN-02 and BETA test loop was conducted. Purpose of the experiment is to study temperature distribution during the transient cooling process. Experiments performed with the variation of the initial temperature of hot rod test section QUEEN-02 of 350 °C and 500 °C as well as the flow of cooling water temperature is 90 °C with the direction of flow from the bottom up from the BETA test loop. The analysis shows that temperature have the same downward trend in its every point thermocouple for the same initial temperature during cooling. Initial temperature of 350 °C hot rods produced when temperatures drop to 90 °C (the same as the temperature of the cooling water) for 78 seconds while the initial temperature of 500 °C produces hot rod drop time 190 seconds. (author)

  14. Calibration of the Flow in the Test Section of the Research Wind Tunnel at DST Group

    Science.gov (United States)

    2015-10-01

    the tunnel. The calibration data are presented and analysed and explanations of flow behaviour are given. 2. Mean-Velocity Measurements 2.1...1073. Defence Science and Technology Organisation , Melbourne, Australia. Erm, L. P. 2003 Calibration of the flow in the extended test section...of the low-speed wind tunnel at DSTO. DSTO-TR-1384. Defence Science and Technology Organisation , Melbourne, Australia. Erm, L. P. 2015

  15. Fracture toughness testing of core from the Cambro-Ordovician Section on the Oak Ridge Reservation

    International Nuclear Information System (INIS)

    Lemiszki, P.J.; Landes, J.D.

    1996-01-01

    The modified ring test was used to determine the mode I fracture toughness of bedrock cores from the DOE Oak Ridge Reservation in east Tennessee. Low porosity sandstones, limestones, and dolostones from the lower part of the Paleozoic section in Copper Creek and Whiteoak Mountain thrust sheets were sampled. In general, the average mode I fracture toughness decreases from sandstone, dolostone, and limestone. The fracture toughness of the limestones varies between rock units, which is related to different sedimentologic characteristics. Quality of results was evaluated by testing cores of Berea Sandstone and Indiana Limestone, which produced results similar to published results

  16. Theoretical and numerical analysis of reinforced concrete beams with confinement reinforcement

    Directory of Open Access Journals (Sweden)

    R. G. Delalibera

    Full Text Available This paper discusses the use of confinement in over-reinforced concrete beams. This reinforcement consists of square stirrups, placed in the compression zone of the beam cross-section, in order to improve its ductility. A parametric numerical study is initially performed, using a finite element computational program that considers the material nonlinearities and the confinement effect. To investigate the influence of the transverse reinforcing ratio on the beam ductility, an experimental program was also conducted. Four over-reinforced beams were tested; three beam specimens with additional transverse reinforcement to confine the beams, and one without it. All specimens were fabricated with a concrete designed for a compressive strength of 25 MPa. The experimental results show that the post-peak ductility factor is proportional to the confining reinforcement ratio, however the same is not observed for the pre-peak ductility factor, which varied randomly with changes in the confining reinforcement ratio. It was also observed from the experiments that the confinement effect tends to be smaller close to the beam neutral axis.

  17. Improving clinical cognitive testing: report of the AAN Behavioral Neurology Section Workgroup.

    Science.gov (United States)

    Daffner, Kirk R; Gale, Seth A; Barrett, A M; Boeve, Bradley F; Chatterjee, Anjan; Coslett, H Branch; D'Esposito, Mark; Finney, Glen R; Gitelman, Darren R; Hart, John J; Lerner, Alan J; Meador, Kimford J; Pietras, Alison C; Voeller, Kytja S; Kaufer, Daniel I

    2015-09-08

    To evaluate the evidence basis of single-domain cognitive tests frequently used by behavioral neurologists in an effort to improve the quality of clinical cognitive assessment. Behavioral Neurology Section members of the American Academy of Neurology were surveyed about how they conduct clinical cognitive testing, with a particular focus on the Neurobehavioral Status Exam (NBSE). In contrast to general screening cognitive tests, an NBSE consists of tests of individual cognitive domains (e.g., memory or language) that provide a more comprehensive diagnostic assessment. Workgroups for each of 5 cognitive domains (attention, executive function, memory, language, and spatial cognition) conducted evidence-based reviews of frequently used tests. Reviews focused on suitability for office-based clinical practice, including test administration time, accessibility of normative data, disease populations studied, and availability in the public domain. Demographic and clinical practice data were obtained from 200 respondents who reported using a wide range of cognitive tests. Based on survey data and ancillary information, between 5 and 15 tests in each cognitive domain were reviewed. Within each domain, several tests are highlighted as being well-suited for an NBSE. We identified frequently used single-domain cognitive tests that are suitable for an NBSE to help make informed choices about clinical cognitive assessment. Some frequently used tests have limited normative data or have not been well-studied in common neurologic disorders. Utilizing standardized cognitive tests, particularly those with normative data based on the individual's age and educational level, can enhance the rigor and utility of clinical cognitive assessment. © 2015 American Academy of Neurology.

  18. Critical Heat Flux Experiments on the Reactor Vessel Wall Using 2-D Slice Test Section

    International Nuclear Information System (INIS)

    Jeong, Yong Hoon; Chang, Soon Heung; Baek, Won-Pil

    2005-01-01

    The critical heat flux (CHF) on the reactor vessel outer wall was measured using the two-dimensional slice test section. The radius and the channel area of the test section were 2.5 m and 10 cm x 15 cm, respectively. The flow channel area and the heater width were smaller than those of the ULPU experiments, but the radius was greater than that of the ULPU. The CHF data under the inlet subcooling of 2 to 25 deg. C and the mass flux 0 to 300 kg/m 2 .s had been acquired. The measured CHF value was generally slightly lower than that of the ULPU. The difference possibly comes from the difference of the test section material and the thickness. However, the general trend of CHF according to the mass flux was similar with that of the ULPU. The experimental CHF data were compared with the predicted values by SULTAN correlation. The SULTAN correlation predicted well this study's data only for the mass flux higher than 200 kg/m 2 .s, and for the exit quality lower than 0.05. The local condition-based correlation was developed, and it showed good prediction capability for broad quality (-0.01 to 0.5) and mass flux ( 2 .s) conditions with a root-mean-square error of 2.4%. There were increases in the CHF with trisodium phosphate-added water

  19. Variation in charges for 10 common blood tests in California hospitals: a cross-sectional analysis

    Science.gov (United States)

    Hsia, Renee Y; Akosa Antwi, Yaa; Nath, Julia P

    2014-01-01

    Objectives To determine the variation in charges for 10 common blood tests across California hospitals in 2011, and to analyse the hospital and market-level factors that may explain any observed variation. Design, setting and participants We conducted a cross-sectional analysis of the degree of charge variation between hospitals for 10 common blood tests using charge data reported by all non-federal California hospitals to the California Office of Statewide Health Planning and Development in 2011. Outcome measures Charges for 10 common blood tests at California hospitals during 2011. Results We found that charges for blood tests varied significantly between California hospitals. For example, charges for a lipid panel ranged from US$10 to US$10 169, a thousand-fold difference. Although government hospitals and teaching hospitals were found to charge significantly less than their counterparts for many blood tests, few other hospital characteristics and no market-level predictors significantly predicted charges for blood tests. Our models explained, at most, 21% of the variation between hospitals in charges for the blood test in question. Conclusions These findings demonstrate the seemingly arbitrary nature of the charge setting process, making it difficult for patients to act as true consumers in this era of ‘consumer-directed healthcare.’ PMID:25127708

  20. Lexical patterns in the reading comprehension section of the toefl test

    Directory of Open Access Journals (Sweden)

    Fabiana Macmillan

    2006-11-01

    Full Text Available The TOEFL (Test of English as a Foreign Language is currently one of the most widely accepted English language proficiency tests. Designed by the ETS (Educational Testing Service, the main purpose of the TOEFL is to determine whether the English language skills of a student applying to a North American college or university are adequate for enrollment into the selected program of study. This study will focus upon the third section of the TOEFL, Reading Comprehension, which consists of several passages followed by questions with different testing purposes. An adaptation of Hoey's (1991 analytical system for the analysis of lexical cohesion in authentic texts will be used to identify bonds connecting reading comprehension questions on the test to key excerpts in the passages they are related to. A number of sample reading comprehension questions taken from practice tests produced by the ETS will be analyzed. The analysis will focus on the relationship between the testing purpose of each question and the type(s of lexical link involved in the identification of the correct answer.

  1. Optimised design and thermal-hydraulic analysis of the IFMIF/HFTM test section

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, S.; Heinzel, V.; Lang, K.H.; Moeslang, A.; Schleisiek, K.; Slobodtchouk, V.; Stratmanns, E.

    2003-10-01

    On the basis of previous concepts, analyses and experiments, the high flux test module (HFTM) for the International Fusion Materials Irradiation Facility (IFMIF) was further optimised. The work focused on the design and the thermal hydraulic analysis of the HFTM section containing the material specimens to be irradiated, the ''test section'', with the main objective to improve the concept with respect to the optimum use of the available irradiation volume and to the temperature of the specimens. Particular emphasis was laid on the application of design principles which assure stable and reproducible thermal conditions. The present work has confirmed the feasibility and suitability of the optimised design of the HFTM test section with chocolate plate like shaped rigs. In particular it has been shown that the envisaged irradiation temperatures can be reached with acceptable temperature differences inside the specimen stack. The latter can be achieved only by additional electrical heating of the axial ends of the capsules. Division of the heater in three sections with separate power supply and control units is necessary. Maintaining of the temperatures during beam-off periods likewise requires electrical heating. The required electrical heaters - mineral isolated wires - are commercially available. The potential of the CFD code STAR-CD for the thermal hydraulic analysis of complex systems like the HFTM was confirmed. Nevertheless, experimental confirmation is desirable. Suitable experiments are under preparation. To verify the assumptions made on the thermal conductivity of the contact faces and layers between the two shells of the rig, dedicated experiments are suggested. The present work must be complemented by a thermal mechanical analysis of the module. Most critical component in this respect seems to be the rig wall. Furthermore, it will be necessary to investigate the response of the HFTM to power transients, and to determine the requirements

  2. Analytical Validation of AmpliChip p53 Research Test for Archival Human Ovarian FFPE Sections.

    Directory of Open Access Journals (Sweden)

    Matthew J Marton

    Full Text Available The p53 tumor suppressor gene (TP53 is reported to be mutated in nearly half of all tumors and plays a central role in genome integrity. Detection of mutations in p53 can be accomplished by many assays, including the AmpliChip p53 Research Test. The AmpliChip p53 Research Test has been successfully used to determine p53 status in hematologic malignancies and fresh frozen solid tissues but there are few reports of using the assay with formalin fixed, paraffin-embedded (FFPE tissue. The objective of this study was to describe analytical performance characterization of the AmpliChip p53 Research Test to detect p53 mutations in genomic DNA isolated from archival FFPE human ovarian tumor tissues. Method correlation with sequencing showed 96% mutation-wise agreement and 99% chip-wise agreement. We furthermore observed 100% agreement (113/113 of the most prevalent TP53 mutations. Workflow reproducibility was 96.8% across 8 samples, with 2 operators, 2 reagent lots and 2 instruments. Section-to-section reproducibility was 100% for each sample across a 60 μm region of the FFPE block from ovarian tumors. These data indicate that the AmpliChip p53 Research Test is an accurate and reproducible method for detecting mutations in TP53 from archival FFPE human ovarian specimens.

  3. Four-Point Bending Strength Testing of Pultruded Fiberglass Composite Wind Turbine Blade Sections

    Energy Technology Data Exchange (ETDEWEB)

    Musial, W.; Bourne, B; Hughes, S; Zuteck, M. D. (MDZ Consulting)

    2001-07-10

    The ultimate strength of the PS Enterprises pultruded blade section was experimentally determined under four-point bending at the National Renewable Energy Laboratory. Thirteen 8-foot long full-scale blade segments were individually tested to determine their maximum moment carrying capability. Three airfoil-bending configurations were tested: high- and low-pressure skin buckling, and low pressure skin buckling with foam interior reinforcement. Maximum strain was recorded for each sample on the compressive and tensile surfaces of each test blade. Test data are compared to the results of three analytical buckling prediction methods. Based on deviations from the linear strain versus load curve, data indicate a post-buckling region. High-pressure side buckling occurred sooner than low-pressure side buckling. The buckling analyses were conservative for both configurations, but high-pressure side buckling in particular was substantially under-predicted. Both high- and low-pressure buckling configurations had very similar failure loads. These results suggests that a redundant load path may be providing strength to the section in the post-buckling region, making the onset of panel buckling a poor predictor of ultimate strength for the PS Enterprises pultrusion.

  4. To test or not to test: A cross-sectional survey of the psychosocial determinants of self-testing for cholesterol, glucose, and HIV

    Directory of Open Access Journals (Sweden)

    Dinant Geert-Jan

    2011-02-01

    Full Text Available Abstract Background Although self-tests are increasingly available and widely used, it is not clear whether their use is beneficial to the users, and little is known concerning the determinants of self-test use. The aim of this study was to identify the determinants of self-test use for cholesterol, glucose, and HIV, and to examine whether these are similar across these tests. Self-testing was defined as using in-vitro tests on body materials, initiated by consumers with the aim of diagnosing a particular disorder, condition, or risk factor for disease. Methods A cross-sectional Internet survey was conducted among 513 self-testers and 600 non-testers, assessing possible determinants of self-test use. The structured questionnaire was based on the Health Belief Model, Theory of Planned Behavior, and Protection Motivation Theory. Data were analyzed by means of logistic regression. Results The results revealed that perceived benefits and self-efficacy were significantly associated with self-testing for all three conditions. Other psychosocial determinants, e.g. gender, cues to action, perceived barriers, subjective norm, and moral obligation, seemed to be more test-specific. Conclusions Psychosocial determinants of self-testing are not identical for all tests and therefore information about self-testing needs to be tailored to a specific test. The general public should not only be informed about advantages of self-test use but also about the disadvantages. Designers of information about self-testing should address all aspects related to self-testing to stimulate informed decision making which, in turn, will result in more effective self-test use.

  5. Confinement contains condensates

    DEFF Research Database (Denmark)

    Brodsky, S. J.; Roberts, C. D.; Shrock, R.

    2012-01-01

    Dynamical chiral symmetry breaking and its connection to the generation of hadron masses has historically been viewed as a vacuum phenomenon. We argue that confinement makes such a position untenable. If quark-hadron duality is a reality in QCD, then condensates, those quantities that have common...... evidence and incidentally expose misconceptions in a recent Comment....

  6. Confinement for More Space

    DEFF Research Database (Denmark)

    Kipnusu, Wycliffe K.; Elsayed, Mohamed; Kossack, Wilhelm

    2015-01-01

    Broadband dielectric spectroscopy and positron annihilation lifetime spectroscopy are employed to study the molecular dynamics and effective free volume of 2-ethyl-1-hexanol (2E1H) in the bulk state and when confined in unidirectional nanopores with average diameters of 4, 6, and 8 nm. Enhanced α...

  7. Damping test results for straight sections of 3-inch and 8-inch unpressurized pipes. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Ware, A.G.; Thinnes, G.L.

    1984-04-01

    EG and G Idaho is assisting the Nuclear Regulatory Commission and the Pressure Vessel Research Committee in supporting a final position on revised damping values for structural analyses of nuclear piping systems. As part of this program, a series of vibrational tests on unpressurized 3-in. and 8-in. Schedule 40 carbon steel piping was conducted to determine the changes in structural damping due to various parametric effects. The 33-ft straight sections of piping were supported at the ends. Additionally, intermediate supports comprising spring, rod, and constant-force hangers, as well as a sway brace and snubbers, were used. Excitation was provided by low-force-level hammer impacts, a hydraulic shaker, and a 50-ton overhead crane for snapback testing. Data was recorded using acceleration, strain, and displacement time histories. This report presents test results showing the effect of stress level and type of supports on structural damping in piping.

  8. Damping test results for straight sections of 3-inch and 8-inch unpressurized pipes

    International Nuclear Information System (INIS)

    Ware, A.G.; Thinnes, G.L.

    1984-04-01

    EG and G Idaho is assisting the Nuclear Regulatory Commission and the Pressure Vessel Research Committee in supporting a final position on revised damping values for structural analyses of nuclear piping systems. As part of this program, a series of vibrational tests on unpressurized 3-in. and 8-in. Schedule 40 carbon steel piping was conducted to determine the changes in structural damping due to various parametric effects. The 33-ft straight sections of piping were supported at the ends. Additionally, intermediate supports comprising spring, rod, and constant-force hangers, as well as a sway brace and snubbers, were used. Excitation was provided by low-force-level hammer impacts, a hydraulic shaker, and a 50-ton overhead crane for snapback testing. Data was recorded using acceleration, strain, and displacement time histories. This report presents test results showing the effect of stress level and type of supports on structural damping in piping

  9. Fracture Toughness of Thick Boride Layers Estimated by the Cross-Sectioned Scratch Test

    Science.gov (United States)

    Campos-Silva, I.; Flores-Jiménez, M.; Bravo-Bárcenas, D.; Rodríguez-Castro, G.; Martínez-Trinidad, J.; Meneses-Amador, A.

    2018-02-01

    New results about the fracture toughness ( K c) of thick boride layers estimated by the cross-sectioned scratch test are presented in this study. The FeB-Fe2B layers developed at the surface of borided AISI 1018 and AISI 1045 steels and the Fe2B layer formed on the borided AISI 1045 steel exposed to a diffusion annealing process (DAP) were used for this purpose. The cross-sectioned scratch tests were performed with a Vickers diamond stylus drawn across the thick boride layer under a constant load to produce a half-cone-shaped fracture near to the top surface of the borided steels. The height of the half-cone-shaped fracture as a function of the cross-sectioned scratch loads was used to determine the fracture toughness of the FeB and Fe2B layers. The results showed a fracture resistance of ˜2.8 {MPa}√ m for the FeB layer formed at the surface of borided AISI 1045 steel. Likewise, the effect of the DAP on the surface of the borided AISI 1045 steel promoted the formation of an exclusively Fe2B layer, with an increase in the fracture toughness of the whole boride layer around 5 {MPa}√ m. Finally, the principle of the technique can be used to minimize the influence of the anisotropic properties on the fracture toughness along the depth of boride layers.

  10. Confined Space Evaluation Student Manual, #19613

    Energy Technology Data Exchange (ETDEWEB)

    Wilmot, David Ezekiel [Los Alamos National Laboratory

    2016-08-29

    Many workplaces contain spaces that are considered to be “confined” because their configuration hinders the activities of employees who must enter into, work in, and exit from them. In general, the permit-required confined spaces (PRCSs) Occupational Safety and Health Administration (OSHA) standard requires that Los Alamos National Laboratory (LANL) evaluate the workplace to determine if any spaces are PRCSs. The standard specifies strict procedures for the evaluation and atmospheric testing of a space before and during an entry by workers. The OSHA PRCS standard provides for alternative (less stringent than full-permit) entry procedures in cases where the only hazard in a space is atmospheric and the hazard can be controlled by forced air. At LANL, all confined spaces or potential confined spaces on LANL-owned or -operated property must be identified and evaluated by a confined space evaluator accompanied by a knowledgeable person. This course provides the information needed by confined space evaluators to make judgements about whether a space is a confined space, and if so, whether the space will require a permit for entry.

  11. New airfoil sections for general aviation aircraft. [cruising and flap development tests

    Science.gov (United States)

    Wentz, W. H., Jr.

    1973-01-01

    A program has been undertaken to develop new airfoil sections suitable for general aviation aircraft, utilizing theoretical and experimental advanced technology developed in recent years primarily for subsonic jet transport and military aircraft. The airfoil development program is one component of the Advanced Technology Light Twin program sponsored by NASA Langley Research Center. Two-dimensional tests of a new airfoil have demonstrated high cruising performance over a fairly wide C sub 1 range, and a C sub 1 max value of 3.69 with Fowler flap and no leading-edge devices. Experimental and theoretical development of additional configurations is under way.

  12. Structural study of cold central plant recycling sections at the National Center for Asphalt Technology (NCAT) test track.

    Science.gov (United States)

    2016-01-01

    In 2012, the Virginia Department of Transportation (VDOT) contracted with the National Center for Asphalt Technology (NCAT) to install, instrument, and monitor three pavement test sections at the NCAT Test Track during the 2012-2014 track cycle. The ...

  13. [Drug using risks screening in primary care patients using the ASSIST test: Cross sectional study].

    Science.gov (United States)

    López-Rodríguez, Juan A; Rigabert, Alina; Gómez Llano, M Nieves; Rubio, Gabriel

    2018-03-15

    The aim of this study is to estimate risky-drug use patterns of consumption of primary care patients. Multicentric descriptive cross-sectional study. five primary health care centers of the South of Madrid. all patients between 16-100 year-old consulting with their family physician. Spanish-validated World Health Organization ASSIST test was use to screen risky drug use in primary care. Total points scored at the test were obtained. A sum of 441 screening test were collected. Mean age was 51,3 years and 51.6% of patients presented a moderate-severe risky drug use out of the nine drugs tested. The more frequent drug use screened were tobacco (41.7%) followed by alcohol (15.4%), hypnotics (13.7%) and cannabis (5.7%). Differences were found between genders in the patterns: men had higher risky drug uses compared to women regarding alcohol and cannabis. Women had higher sedatives/hypnotics consumption prevalence. A 16% of patients presented with polyconsumption drug use patterns. There is risk derived from drug misuse in primary care for tobacco, alcohol, hypnotics and cannabis as detected by the ASSIST test. There is a higher rate of hypnotics than expected. Copyright © 2018 The Authors. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. HIV testing and tolerance to gender based violence: a cross-sectional study in Zambia.

    Directory of Open Access Journals (Sweden)

    Sara Gari

    Full Text Available This paper explores the effect of social relations and gender-based conflicts on the uptake of HIV testing in the South and Central provinces of Zambia. We conducted a community-based cross-sectional study of 1716 randomly selected individuals. Associations were examined using mixed-effect multivariable logistic regression. A total of 264 men (64% and 268 women (56% had never tested for HIV. The strongest determinants for not being tested were disruptive couple relationships (OR = 2.48 95% CI = 1.00-6.19; tolerance to gender-based violence (OR = 2.10 95% CI = 1.05-4.32 and fear of social rejection (OR = 1.48 95% CI = 1.23-1.80. In the Zambian context, unequal power relationships within the couple and the community seem to play a pivotal role in the decision to test which until now have been largely underestimated. Policies, programs and interventions to rapidly increase HIV testing need to urgently address gender-power inequity in relationships and prevent gender-based violence to reduce the negative impact on the lives of couples and families.

  15. Primary care patient willingness for genetic testing for salt-sensitive hypertension: a cross sectional study.

    Science.gov (United States)

    Okayama, Masanobu; Takeshima, Taro; Ae, Ryusuke; Harada, Masanori; Kajii, Eiji

    2013-10-09

    The current research into single nucleotide polymorphisms has extended the role of genetic testing to the identification of increased risk for common medical conditions. Advances in genetic research may soon necessitate preparation for the role of genetic testing in primary care medicine. This study attempts to determine what proportion of patients would be willing to undergo genetic testing for salt-sensitive hypertension in a primary care setting, and what factors are related to this willingness. A cross-sectional study using a self-report questionnaire was conducted among outpatients in primary care clinics and hospitals in Japan. The main characteristics measured were education level, family medical history, personal medical history, concern about hypertension, salt preference, reducing salt intake, and willingness to undergo genetic testing for salt-sensitive hypertension. Of 1,932 potential participants, 1,457 (75%) responded to the survey. Of the respondents, 726 (50%) indicated a willingness to undergo genetic testing. Factors related to this willingness were being over 50 years old (adjusted odds ratio [ad-OR] = 1.42, 95% Confidence interval = 1.09 - 1.85), having a high level of education (ad-OR: 1.83, 1.38 - 2.42), having a family history of hypertension (ad-OR: 1.36, 1.09 - 1.71), and worrying about hypertension (ad-OR: 2.06, 1.59 - 2.68). Half of the primary care outpatients surveyed in this study wanted to know their genetic risk for salt-sensitive hypertension. Those who were worried about hypertension or had a family history of hypertension were more likely to be interested in getting tested. These findings suggest that primary care physicians should provide patients with advice on genetic testing, as well as address their anxieties and concerns related to developing hypertension.

  16. Japanese magnetic confinement fusion research

    International Nuclear Information System (INIS)

    McKenney, B.L.; McGrain, M.; Horton, C.W.; Rutherford, P.H.

    1990-01-01

    This report is the work of six US scientists who surveyed and assessed Japanese research and development in magnetic fusion. All of the panelists are very familiar with Japanese fusion research through their knowledge of the published scientific literature and through personal contacts with Japanese colleagues and with US colleagues who have visited Japanese research facilities. This report concentrates on the period from the early 1980s through June 1989. The technical accomplishments during this period are reviewed, and the Japanese capabilities and outlook for future contributions are assessed. Detailed evaluations are provided in the areas of basic and applied plasma physics, tokamak confinement, alternate confinement approaches, plasma technology, and fusion nuclear technology and materials. With a sustained national commitment, Japan will surpass US and West European capabilities in the early to middle 1990s in several important areas of fusion research and development. For example, it is expected that the planned upgrade of the Japanese JT-60 tokamak will surpass both the US Tokamak Fusion Test Reactor (TFTR) and the Joint European tours (JET) in the usual measures of plasma performance in the 1992 to 1993 timeframe, and will take a clear international lead in large-tokamak research by 1994 to 1995. The Japanese fusion program has the human and technological resources required to build and operate a fusion engineering test reactor without external participation. By the same measure, Japan would be a highly desirable partner in the bilateral undertaking of such a project

  17. Topological confinement and superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Al-hassanieh, Dhaled A [Los Alamos National Laboratory; Batista, Cristian D [Los Alamos National Laboratory

    2008-01-01

    We derive a Kondo Lattice model with a correlated conduction band from a two-band Hubbard Hamiltonian. This mapping allows us to describe the emergence of a robust pairing mechanism in a model that only contains repulsive interactions. The mechanism is due to topological confinement and results from the interplay between antiferromagnetism and delocalization. By using Density-Matrix-Renormalization-Group (DMRG) we demonstrate that this mechanism leads to dominant superconducting correlations in aID-system.

  18. Innovative confinement concepts workshop

    International Nuclear Information System (INIS)

    Kirkpatrick, R.C.

    1998-01-01

    The Innovative Confinement Concepts Workshop occurred in California during the week preceding the Second Symposium on Current Trends in International Fusion Research. An informal report was made to the Second Symposium. A summary of the Workshop concluded that some very promising ideas were presented, that innovative concept development is a central element of the restructured US DOE. Fusion Energy Sciences program, and that the Workshop should promote real scientific progress in fusion

  19. Energy confinement in tokamaks

    International Nuclear Information System (INIS)

    Sugihara, M.; Singer, C.

    1986-08-01

    A straightforward generalization is made of the ohmic heating energy confinement scalings of Pfeiffer and Waltz and Blackwell et. al. The resulting model is systematically calibrated to published data from limiter tokamaks with ohmic, electron cyclotron, and neutral beam heating. With considerably fewer explicitly adjustable free parameters, this model appears to give a better fit to the available data for limiter discharges than the combined ohmic/auxiliary heating model of Goldston

  20. Confined exciton spectroscopy

    International Nuclear Information System (INIS)

    Torres, Clivia M.S.

    1998-01-01

    Full text: In this work, the exciton is considered as a sensor of the electronic and optical properties of materials such as semiconductors, which have size compared to the exciton De Broglie wavelength, approximately 20 nm, depending on the semiconductor. Examples of electron-phonon, electron-electron, photon-electron, exciton-polariton, phonon-plasmon, are presented, under different confinement conditions such as quantum wells, superlattices

  1. 77 FR 28340 - Revocation of TSCA Section 4 Testing Requirements for One High Production Volume Chemical Substance

    Science.gov (United States)

    2012-05-14

    ... Revocation of TSCA Section 4 Testing Requirements for One High Production Volume Chemical Substance AGENCY...]- (CAS No. 1324-76-1), also known as C.I. Pigment Blue 61. EPA is basing its decision to take this action... is proposing to amend the TSCA section 4(a) chemical testing requirements for one high production...

  2. Multishell inertial confinement fusion target

    International Nuclear Information System (INIS)

    Holland, J.R.; Del Vecchio, R.M.

    1984-01-01

    A method of fabricating multishell fuel targets for inertial confinement fusion usage. Sacrificial hemispherical molds encapsulate a concentric fuel pellet which is positioned by fiber nets stretched tautly across each hemispherical mold section. The fiber ends of the net protrude outwardly beyond the mold surfaces. The joint between the sacrificial hemispheres is smoothed. A ceramic or glass cover is then deposited about the finished mold surfaces to produce an inner spherical surface having continuously smooth surface configuration. The sacrificial mold is removed by gaseous reaction accomplished through the porous ceramic cover prior to enclosing of the outer sphere by addition of an outer coating. The multishell target comprises the inner fuel pellet concentrically arranged within a surrounding coated cover or shell by fiber nets imbedded within the cover material

  3. Heavy-Section Steel Technology Program intermediate-scale pressure vessel tests

    International Nuclear Information System (INIS)

    Bryan, R.H.; Merkle, J.G.; Smith, G.C.; Whitman, G.D.

    1977-01-01

    The tests of intermediate-size vessels with sharp flaws permitted the comparison of experimentally observed behavior with analytical predictions of the behavior of flawed pressure vessels. Fracture strains estimated by linear elastic fracture mechanics (LEFM) were accurate in the cases in which the flaws resided in regions of high transverse restraint and the fracture toughness was sufficiently low for unstable fracture to occur prior to yielding through the vessel wall. When both of these conditions were not present, unstable fracture did occur, always preceded by stable crack growth; and the cylinders with flaws initially less than halfway through the wall attained gross yield prior to burst. Predictions of failure pressure of the vessels with flawed nozzles, based upon LEFM estimates of failure strain, were very conservative. LEFM calculations of critical load were based upon small-specimen fracture toughness test data. Whenever gross yielding preceded failure, the actual strains achieved were considerably greater than the estimated strains at failure based on LEFM. In such cases the strength of the vessel may be no longer dependent upon plane-strain fracture toughness but upon the capacity of the cracked section to carry the imposed load stably in the plastic range. Stable crack growth, which has not been predictable quantitatively, is an important factor in elastic-plastic analysis of strength. The ability of the flawed vessels to attain gross yield in unflawed sections has important qualitative implications on pressure vessel safety margins. The gross yield condition occurs in light-water-reactor pressure vessels at about 2 x design pressure. The intermediate vessel tests that demonstrated a capacity for exceeding this load confirm that the presumed margin of safety is not diminished by the presence of flaws of substantial size, provided that material properties are adequate

  4. Factors affecting voluntary HIV counselling and testing among men in Ethiopia: a cross-sectional survey

    Directory of Open Access Journals (Sweden)

    Leta Tesfaye H

    2012-06-01

    Full Text Available Abstract Background Voluntary HIV counselling and testing (VCT is one of the key strategies in the HIV/AIDS prevention and control programmes in Ethiopia. However, utilization of this service among adults is very low. The aim of the present study was to investigate factors associated with VCT utilization among adult men since men are less likely than women to be offered and accept routine HIV testing. Methods The study utilized data from the Ethiopian Demographic Health Survey (EDHS 2005, which is a cross-sectional survey conducted on a nationally representative sample. Using cluster sampling, 6,778 men aged 15–59 years were selected from all the eleven administrative regions in Ethiopia. Logistic regression was used to analyze potential factors associated with VCT utilization. Results Overall, 21.9% of urban men and 2.6% of rural men had ever tested for HIV through VCT and most of them had learned their HIV test result. Having no stigmatizing attitudes toward people living with HIV/AIDS was found to be strongly and positively associated with VCT utilization in both urban and rural strata. In rural areas HIV test rates were higher among younger men (aged ≤44 years and those of higher socio-economic position (SEP. Among urban men, risky sexual behaviour was positively associated with VCT utilization whereas being Muslim was found to be inversely associated with utilization of VCT. Area of residence as well as SEP strongly affected men’s level of stigmatizing attitudes toward people living with HIV/AIDS. Conclusions VCT utilization among men in Ethiopia was low and affected by HIV/AIDS-related stigma and residence. In order to increase VCT acceptability, HIV/AIDS prevention and control programs in the country should focus on reducing HIV/AIDS-related stigma. Targeting rural men with low SEP should be given first priority when designing, expanding, and implementing VCT services in the country.

  5. Test flattening in the larger foraminifer Heterostegina depressa: predicting bathymetry from axial sections

    Science.gov (United States)

    Eder, Wolfgang; Hohenegger, Johann; Kinoshita, Shunichi; Wöger, Julia; Briguglio, Antonino

    2016-04-01

    The cosmopolite foraminifer Heterostegina depressa has been a target of studies, describing its internal and external morphology, ecology and biology. During the last decades many researcher concentrated on test morphology and described its maturoevolute shape. Furthermore, a continuously increasing trend of test flattening along water depth has been described multiple times. However, the most common measurements, such as the thickness/diameter ratio, are too dependent on individual size to pose as an accurate tool. /newline Therefore a growth invariant character has been used to describe the change of thickness through the ontogeny of H. depressa. To compute this, the thickness at the half-radius, the so-called mediolateral thickness, of five whorls has been measured in 127 axial section of H. depressa. Based on this the ontogenetic change in thickness has been computed for specimens from different depth intervals of the slope of Sesoko-Jima, NW-Okinawa. In addition, this has been compared with the actual thickness and the corresponding radii at the same measuring points. The latter describes how thickness would change according to the thickness/diameter ratio./newline Hence, our analysis clearly quantifies a continuous transition of individuals with thicker central parts to individuals with flatter central parts along the water depth gradient. This is most likely controlled by light intensity, since photosymbionts (diatoms) of H. depressa are most active at low irradiation levels. Thus, shallower specimens grow thicker tests to reduce light penetration, while deeper specimens increase their surface to reach a better light exposure. Due to its broad water depth distribution H. depressa is a perfect model species to calibrate test flattening as bathymetric signal for fossil assemblages. Since similar ecological constraints are assumed for fossil nummulitid taxa, useful palaeobathymetric information might be gathered from studying test flattening in extinct species

  6. Use of a scenario-development procedure to identify potentially disruptive scenarios, Greater Confinement Disposal facility, Area 5, Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Guzowski, R.V. [Science Applications International Corp., San Diego, CA (United States)]|[Sandia National Labs., Albuquerque, NM (United States). Safety and Risk Assessment Dept.

    1994-12-31

    The Greater Confinement Disposal (GCD) facility includes four boreholes that contain transuranic (TRLT) waste. Presence of the TRU waste means that this facility must comply with the US Environmental Protection Agency`s Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Waste-Final Rule 40 CFR Part 191. To comply with the Containment Requirements of this rule, all potentially disruptive events and processes, and by implication all potentially disruptive combinations of events and processes (scenarios), must be identified for possible inclusion in performance assessments. Screening of the FEPs identified four events for scenario development: exploratory drilling for natural resources, drilling withdrawal wells, irrigation, and subsidence. Recent environmental-isotope analyses of the vadose zone suggest that radionuclide transport from the boreholes to the water table by infiltration is not a feasible transport mechanism within the time frame of regulatory concern. For this reason, the event of drilling withdrawal wells was merged with exploratory drilling for resources. The descriptions of the remaining three events were modified slightly to aid in estimation of event probabilities and consequence analyses. The three events are: exploratory drilling for resources penetrates a TRU borehole, irrigation occurs at the Radioactive Waste Management Site (RWMS), and subsidence occurs at the RWMS. Use of a logic diagram with these three events resulted in the construction of eight scenarios, including base-case (undisturbed) conditions. Screening these scenarios at this stage of scenario development was beyond the scope of this task. Based on the implementation assumptions, this scenario-development procedure produced a comprehensive set of mutually exclusive scenarios that are reproducible and auditable for use in GCD performance assessments.

  7. Dental anxiety prediction using Venham Picture test: A preliminary cross-sectional study

    Directory of Open Access Journals (Sweden)

    M Agarwal

    2013-01-01

    Full Text Available Anxiety or fearfulness affects a child′s behavior, and to a large extent, determines the success of a dental treatment. It is essential to identify anxious children at the earliest age possible rather than simply deal with them later. It is crucial that every effort be made to ensure a positive experience for each child patient. Appropriate acknowledgment of patient′s anxiety can solidify their confidence and allows the pediatric dentist an informed review of potential management options specific to every individual. In the present cross-sectional study, Venham Picture, a psychometric test, was used to estimate the prevalence of dental anxiety among children in the age group 6-10 years, with and without previous dental experience.

  8. The effect of inlet flow oscillations on reflooding of a tubular test section

    International Nuclear Information System (INIS)

    Oh, S.; Banerjee, S.; Yadigaroglu, G.

    1983-01-01

    The reflooding of a vertical channel under oscillatory inlet flow conditions has been investigated experimentally. Compared to constant injection, oscillations always increase the liquid carryover in the early stages of reflooding. As reflooding progresses, the enhancement diminishes. The crossover point roughly coincides with saturation of the liquid at the quench front (QF). The higher liquid carryover at the beginning increases downstream heat transfer and speeds up QF propagation. But this higher liquid carryover, in turn, reduces the test section mass accumulation rate and delays QF propagation at later stages. The enhancement of liquid carryover, and the early increase and subsequent decrease in quench velocity are all accentuated as the oscillation amplitude and frequency increase. Large amplitude oscillations change the characteristics of QF propagation and the heat transfer immediately downstream of QF substantially. Correlations based on constant-injection reflooding data are not adequate, even if they are applied on an average local-conditions basis

  9. Test of the universal rise of hadronic total cross sections at super-high energies

    International Nuclear Information System (INIS)

    Ishida, Muneyuki; Igi, Keiji

    2007-01-01

    The increase of the total cross sections at very high energies described by log 2 (s/s 0 ) appears to be confirmed. In the analysis of the COMPETE collaboration in the Particle Data Group (2006), the Blog 2 (s/s 0 ) was assumed to extend the universal rise of all the total hadronic cross sections to reduce the number of adjustable parameters. We test if the assumption on the universality of B is justified, through investigation of the values of B for π ± p(K ± p) and pp,pp scatterings. We search for the simultaneous best fit to the σ tot and ρ ratios, using a constraint from the FESR of the P' type for π -+ p scatterings and constraints that are free from the unphysical regions for the pp, pp and K ± p scatterings. By including rich information of the low-energy scattering data owing to the use of FESR, the errors of the B parameters decrease especially for πp. The resulting value of B pp is consistent with B πp within two standard deviations, which appears to support the universality hypothesis. (orig.)

  10. Measurement of single-top cross section and test of anomalous $Wtb$ coupling

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ji-Eun [Seoul National Univ. (Korea, Republic of)

    2010-01-01

    The top quark is most often produced in tt pairs via the strong interaction, however electroweak production of a singly-produced top quark is also possible. Electroweak single-top production is more difficult to observe than tt production. Studying single-top production is important for the following reasons. It provides direct measurement of the CKM matrix element and also single-top events are a background to several searches for SM or non-SM signals, such as Higgs boson searches. The information of spin polarization of top-quark can be used to t est anomalous W-t-b coupling. This thesis describes the result of a measurement of single-top cross-section and a test of anomalous W-t-b coupling using 4.8 f b-1 of data collected by the CDF Run II experiment at the Fermilab Tevatron. The measured cross-section is 1.83$+0.7\\atop{-0.6}$ pb and measured limit of |Vtb| is 0.41 at 95% CL. The fraction of V+A coupling is 0 ± 28 (%).

  11. Assesment of artificial caries lesions through scanning electron microscopy and cross-sectional microhardness test

    Directory of Open Access Journals (Sweden)

    Mirian de Waele Souchois de Marsillac

    2013-01-01

    Materials and Methods: Ten human permanent molars were used in this experiment. One section of each tooth was double coated with nail varnish except for a limited central area sized 2.5 mm × 1 mm (2.5 mm 2 . Each specimen was individually exposed to 10.4 ml of a demineralizing solution at pH 5.0, during 42 days (37°C without agitation. Samples were sectioned in the center of the AAWSL and one half was analyzed in SEM and the other half was subjected to CSMH. Descriptive statistics was performed to determine mean depth of the lesion. Results: The mean depth of AAWSL was 100 μm (s.d. =12.1 and a white dull rough surface could be detected by the unaided eye. SEM images demonstrated that although some surface areas of the lesion appeared to be relatively intact, erosion was present. A prismatic pattern of dissolution was observed in all samples with an enlargement of the prism sheaths and some samples had also sites of destruction of prism cores. Conclusion: This methodology can be used to induce AAWSLs in human dental enamel but surface erosion has to be taken into account when performing CSMH test.

  12. Velocimetry modalities for secondary flows in a curved artery test section

    Science.gov (United States)

    Bulusu, Kartik V.; Elkins, Christopher J.; Banko, Andrew J.; Plesniak, Michael W.; Eaton, John K.

    2014-11-01

    Secondary flow structures arise due to curvature-related centrifugal forces and pressure imbalances. These flow structures influence wall shear stress and alter blood particle residence times. Magnetic resonance velocimetry (MRV) and particle image velocimetry (PIV) techniques were implemented independently, under the same physiological inflow conditions (Womersley number = 4.2). A 180-degree curved artery test section with curvature ratio (1/7) was used as an idealized geometry for curved arteries. Newtonian blood analog fluids were used for both MRV and PIV experiments. The MRV-technique offers the advantage of three-dimensional velocity field acquisition without requiring optical access or flow markers. Phase-averaged, two-dimensional, PIV-data at certain cross-sectional planes and inflow phases were compared to phase-averaged MRV-data to facilitate the characterization of large-scale, Dean-type vortices. Coherent structures detection methods that included a novel wavelet decomposition-based approach to characterize these flow structures was applied to both PIV- and MRV-data. The overarching goal of this study is the detection of motific, three-dimensional shapes of secondary flow structures using MRV techniques with guidance obtained from high fidelity, 2D-PIV measurements. This material is based in part upon work supported by the National Science Foundation under Grant Number CBET-0828903, and GW Center for Biomimetics and Bioinspired Engineering (COBRE).

  13. Experimental and Theoretical Study of Air Flow with Obstruction Through Test Section of Wind Tunnel

    Directory of Open Access Journals (Sweden)

    Hayder Kraidy Rashid

    2016-03-01

    Full Text Available This paper estimates the sound and flow generated by a turbulent air flow in a duct from the knowledge of mean quantities (average velocity and sound pressure level.The sound excitation by fluid flow through duct can be used to predict fluid behavior. This behavior can be carried out by discovering the relation between sound excitation and fluid flow parameters like Reynolds number, Strouhal number and frequencies of turbulent fluid flow. However, the fluid flow container stability has to be taken in account simultaneously with fluid flow effect on sound generation and propagation. The experimental system used in this work is air flow through subsonic wind tunnel duct.The sound pressure levels of air flows through test section of subsonic wind tunnel (at three air flow velocities2.5, 7.3 and 12.5 m/s respectively were carried out experimentally. The sound excitation or generation by air flow throughout the test section of subsonic wind tunnel without any obstruction can't be used to imagine the fluid behavior. To predict fluid flow properties,an infinite cylinder was immersed in order to obstruct the air flow and generate a new source of sound.This case is relevant to a wide range of engineering applications including aircraft landing gear, rail pantographs and automotive side-mirrors. Sound measurements have been taken in an anechoic room at Babylon University. ANSYS program software is used to simulate all experimental results.The experimental and theoretical data that were presented in this paper will give further insight into the underlying sound generation mechanism.In the presented work, the linkage between sound generation and CFD results using thepresented work results and ANSYS simulation results was done.The results discuss the effects of fluid flow parameters such as Reynolds and Strouhal numbers on the sound generation, propagation features and vice-versa. The results are compared with other researchers which give good agreements.

  14. Inertial confinement fusion (ICF)

    International Nuclear Information System (INIS)

    Nuckolls, J.

    1977-01-01

    The principal goal of the inertial confinement fusion program is the development of a practical fusion power plant in this century. Rapid progress has been made in the four major areas of ICF--targets, drivers, fusion experiments, and reactors. High gain targets have been designed. Laser, electron beam, and heavy ion accelerator drivers appear to be feasible. Record-breaking thermonuclear conditions have been experimentally achieved. Detailed diagnostics of laser implosions have confirmed predictions of the LASNEX computer program. Experimental facilities are being planned and constructed capable of igniting high gain fusion microexplosions in the mid 1980's. A low cost long lifetime reactor design has been developed

  15. Hadrosynthesis and Quark Confinement

    Directory of Open Access Journals (Sweden)

    Satz Helmut

    2014-04-01

    Full Text Available Multihadron production in high energy collisions, from e+e− annihilation to heavy ion interactions, shows remarkable thermal behaviour, specified by a universal “Hagedorn” temperature. We argue that this hadronic radiation is formed by tunnelling through the event horizon of colour confinement, i.e., that it is the QCD counterpart of Hawking-Unruh radiation from black holes. It is shown to be emitted at a universal temperature TH ≃ (σ/2π1/2, where σ denotes the string tension. Since the event horizon does not allow information transfer, the radiation is thermal “at birth”.

  16. Confinement and 4-manifolds

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    In this talk I will survey a connection between two very challenging problems, one in physics and one in math. The physics problem involves quantitative understanding of confinement in a system with least amount of supersymmetry that has been studied so far and that has a wide range of applications, from semi-realistic string models to qualitatively new examples of gauge-gravity duality. Surprisingly, the rich physics of this system translates into incredibly rich mathematics of the only remaining unsolved case of the Poincare conjecture.

  17. COMPORTAMIENTO DE UN MATERIAL GRANULAR NO TRATADO EN ENSAYOS TRIAXIALES CÍCLICOS CON PRESIÓN DE CONFINAMIENTO CONSTANTE Y VARIABLE BEHAVIOR OF AN UNBOUND GRANULAR MATERIAL IN CYCLIC TRIAXIAL TESTS WITH CONSTANT AND VARIABLE CONFINING PRESSURE

    Directory of Open Access Journals (Sweden)

    Hugo Alexander Rondón Quintana

    2008-12-01

    Full Text Available En un pavimento, cada una de las capas de la estructura experimenta bajo una carga vehicular ciclos de esfuerzo con componentes vertical, horizontal y de corte. Para el estudio de materiales granulares no tratados (utilizados para conformar capas de base y subbase, la mayor parte de las investigaciones se realizan empleando equipos triaxiales cíclicos en donde sólo la carga vertical es cíclica y la presión de confinamiento permanece constante durante el ensayo. Un ensayo que reproduce mejor la forma como se distribuyen los esfuerzos en estas capas es el ensayo triaxial cíclico con presión de confinamiento variable. En este ensayo se pueden modelar las componentes cíclicas tanto en el sentido vertical como horizontal. A pesar que son ensayos distintos, la ingeniería de pavimentos supone que la respuesta que experimentan estos materiales en estos ensayos es similar, lo anterior basado en algunos estudios realizados en la década de los setenta. En la presente investigación se diseña y desarrolla un programa experimental más detallado, para comparar el comportamiento que desarrolla un material granular no tratado en estos ensayos. De los resultados se evidencia que sólo para algunas trayectorias de esfuerzo, la dirección y la acumulación de la deformación vertical y volumétrica es similar.In a pavement structure, passing wheel loads impose cyclic stresses consisting of vertical, horizontal and shear components. Studies of the behavior of unbound granular materials (UGM, used for base and sub-base layers under cyclic loading are mostly performed using the axisymmetric triaxial test with constant confining pressure (CCP test and a cyclic variation of the axial stress. However, in this type of test only the vertical component of the cyclic stress path is considered. The oscillation of the horizontal stress can be reproduced by an additional cyclic variation of the confining pressure (VCP test. CCP and VCP tests are sometimes assumed to

  18. Operation and post operative examinations on the 1 MW test section SDP-1

    International Nuclear Information System (INIS)

    Casalini, P.; Valentini, P.; Urbani, A.

    1975-01-01

    The tests carried out were essentially, of general interest and could regard the general Performance and the behavior of the materials. The last aspect was rather interesting as the steam generator coil consists of a steel which has not been yet homologated in Italy. As already specified, the geometry of the steam generator was somewhat particular: it consisted of a stainless steel (Type AISI 316) cylindrical envelope with a diameter of about 500 mm and about 4 m high, with inside an helicoidal duct having a rectangular section, also in AISI 316 stainless steel. Three helicoidal tubes with an outer diameter of 26,9 mm and a thickness of 5 mm, out of ferritic steel - Type Mannesman F 11 were arranged inside the duct. The rectangular duct was run through by sodium downwards, while water/steam was running through the three parallel tubes upwards. The main characteristics pertaining to the steam generator and the nominal operational data are given. All the tests carried out on the tube coil resulted in noticeable alteration due to operation in sodium. In particular, with regard to the absence of variation of the carbon content between the inner and outer side in all the specimens analyzed, one can conclude that no considerable mass transfer occurred in the tube

  19. Quark Confinement and Strings

    Science.gov (United States)

    't Hooft, Gerardus

    QCD was proposed as a theory for the strong interactions long before we had any idea as to how it could be that its fundamental constituents, the quarks, are never seen as physical particles. Massless gluons also do not exist as free particles. How can this be explained? The first indication that this question had to be considered in connection with the topological structure of a gauge theory came when Nielsen and Olesen observed the occurrence of stable magnetic vortex structures [1] in the Abelian Higgs model. Expanding on such ideas, the magnetic monopole solution was found [2]. Other roundabout attempts to understand confinement involve instantons. Today, we have better interpretations of these topological structures, including a general picture of the way they do lead to unbound potentials confining quarks. It is clear that these unbound potentials can be ascribed to a string-like structure of the vortices formed by the QCD field lines. Can string theory be used to analyze QCD? Many researchers think so. The leading expert on this is Sacha Polyakov. In his instructive account he adds how he experienced the course of events in Gauge Theory, emphasizing the fact that quite a few discoveries often ascribed to researchers from the West, actually were made independently by scientists from the Soviet Union…

  20. Confinement from correlation functions

    Science.gov (United States)

    Fister, Leonard; Pawlowski, Jan M.

    2013-08-01

    We compute the Polyakov loop potential in Yang-Mills theory from the fully dressed primitively divergent correlation functions only. This is done in a variety of functional approaches ranging from functional renormalization group equations over Dyson-Schwinger equations to two-particle irreducible functionals. We present a confinement criterion that links the infrared behavior of propagators and vertices to the Polyakov loop expectation value. The present work extends the works of [J. Braun , Phys. Lett. B 684, 262 (2010)PYLBAJ0370-2693; F. Marhauser and J. M. Pawlowski, arXiv:0812.1144; J. Braun , Eur. Phys. J. C 70, 689 (2010)EPCFFB1434-6044] to general functional methods and sharpens the confinement criterion presented there. The computations are based on the thermal correlation functions in the Landau gauge calculated in [L. Fister and J. M. Pawlowski, arXiv:1112.5440; L. Fister and J. M. Pawlowski, arXiv:1112.5429; L. Fister, Ph.D. thesis, Heidelberg University, 2012].

  1. Greater-confinement disposal

    International Nuclear Information System (INIS)

    Trevorrow, L.E.; Schubert, J.P.

    1989-01-01

    Greater-confinement disposal (GCD) is a general term for low-level waste (LLW) disposal technologies that employ natural and/or engineered barriers and provide a degree of confinement greater than that of shallow-land burial (SLB) but possibly less than that of a geologic repository. Thus GCD is associated with lower risk/hazard ratios than SLB. Although any number of disposal technologies might satisfy the definition of GCD, eight have been selected for consideration in this discussion. These technologies include: (1) earth-covered tumuli, (2) concrete structures, both above and below grade, (3) deep trenches, (4) augered shafts, (5) rock cavities, (6) abandoned mines, (7) high-integrity containers, and (8) hydrofracture. Each of these technologies employ several operations that are mature,however, some are at more advanced stages of development and demonstration than others. Each is defined and further described by information on design, advantages and disadvantages, special equipment requirements, and characteristic operations such as construction, waste emplacement, and closure

  2. First prediction of the direct effect of a confined atom on photoionization of the confining fullerene

    International Nuclear Information System (INIS)

    McCune, Matthew A; De, Ruma; Chakraborty, Himadri S; Madjet, Mohamed E

    2010-01-01

    We predict that the confined atom can qualitatively modify the energetic photoionization of some cage levels, even though these levels are of very dominant fullerene character. The effect imposes strong new oscillations in the cross sections which are forbidden to the ionization of empty fullerenes. Results are presented for the AratC 60 endofullerene compound. (fast track communication)

  3. Confinement effects in sesquioxydes

    Energy Technology Data Exchange (ETDEWEB)

    Mercier, B. [Laboratoire de Physico-Chimie des Materiaux Luminescents, UMR 5620 du CNRS, Universite Claude Bernard Lyon I, 10 rue A.M. Ampere 69622 Villeurbanne Cedex (France); Dujardin, C. [Laboratoire de Physico-Chimie des Materiaux Luminescents, UMR 5620 du CNRS, Universite Claude Bernard Lyon I, 10 rue A.M. Ampere 69622 Villeurbanne Cedex (France); Ledoux, G. [Laboratoire de Physico-Chimie des Materiaux Luminescents, UMR 5620 du CNRS, Universite Claude Bernard Lyon I, 10 rue A.M. Ampere 69622 Villeurbanne Cedex (France)]. E-mail: ledoux@pcml.univ-lyon1.fr; Louis, C. [Laboratoire de Physico-Chimie des Materiaux Luminescents, UMR 5620 du CNRS, Universite Claude Bernard Lyon I, 10 rue A.M. Ampere 69622 Villeurbanne Cedex (France); Tillement, O. [Laboratoire de Physico-Chimie des Materiaux Luminescents, UMR 5620 du CNRS, Universite Claude Bernard Lyon I, 10 rue A.M. Ampere 69622 Villeurbanne Cedex (France); Perriat, P. [Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, UMR 5510 du CNRS, INSA de Lyon, 69622 Villeurbanne Cedex (France)

    2006-07-15

    When the size of a particle is decreased to nano-scales, confinement effects induce strong changes. The luminescence of Eu{sup 3+}-doped Gd{sub 2}O{sub 3} nanoparticles has been studied as a function of both the temperature and the size of the nanoparticles. Two consequences of the small sizes in Eu{sup 3+}-doped Gd{sub 2}O{sub 3} are observed. First the linewidth of the Eu{sup 3+} transitions are inhomogeneously broadened at low temperature, and second the population of the ground and the first excited state of Eu{sup 3+} as a function of temperature differs depending on the size: at low temperatures, the smaller the particles, the less populated the first excited state is. The explanation of this second phenomenon could be the absence of very low-energy phonons in small particles.

  4. Testing an ionization chamber with gaseous samples and measurements of the (n, alpha) reaction cross sections

    CERN Document Server

    Gledenov, Yu M; Salatskii, V I; Sedyshev, P V; Andrzejewski, J; Szalanski, P

    1999-01-01

    A new ionization chamber with gaseous samples (GIC) has been designed and tested on the thermal and resonance neutron beams of FLNP's neutron sources. The exposed gas volume serves as a target for neutrons. The obtained thermal cross sections for the sup 1 sup 7 O(n, alpha) sup 1 sup 4 C, sup 2 sup 1 Ne(n, alpha) sup 1 sup 8 O and sup 3 sup 6 Ar(n, alpha) sup 3 sup 3 S reactions are (233+-12) mb, (0.18+-0.09) mb and (5.43+-0.27) mb, respectively. These measurements have been performed on a pure beam of thermal neutrons from the high flux reactor IBR-2; and they demonstrated high efficiency and reliability of the method. Compared to samples on substrates, the application of gaseous samples makes the beam background essentially lower, and what is more important, the background component is totally absent due to the absence of Li and B microimpurities in gaseous samples while they do present in the samples on substrates. The method is also applicable to measurements with resonance neutrons. The recovery capabili...

  5. Estimation of the hydraulic parameters of a confined geologic formation from slug test in fully penetrating well using a complete quasi-steady flow model in a forward and in an inverse optimal estimation procedure

    Science.gov (United States)

    Rozos, Evangelos; Akylas, Evangelos; Koussis, Antonis D.

    2013-04-01

    Slug tests offer a fast and inexpensive means of estimating the hydraulic parameters of a geologic formation, and are very well suited for contaminated site assessment because no water is essentially withdrawn. In the great majority of slug tests performed in wells fully penetrating confined geologic formations, and for over-damped conditions, the response data are evaluated with the transient-flow model of Cooper et al. (1967) when the radial hydraulic conductivity Kr and the coefficient of specific storage Ss are to be estimated. That particular analytical solution, however, is computationally involved and awkward to use. Thus, groundwater professionals often use a few pre-prepared type-curves to fit the data by a rough matching procedure, visually or computationally. On the other hand, the method of Hvorslev (1951), which assumes the flow to be quasi-steady, is much simpler but yields only Kr-estimates. Koussis and Akylas (2012) have derived a complete quasi-steady flow model that includes a storage balance inside the aquifer and allows estimating both Kr and Ss, through matching of the well response data to a (dimensionless) type-curve. That model approximates the model of Cooper et al. closely and has the practical advantage that its solution type-curves are generated very simply, even using an electronic spreadsheet. Thus, an optimal fit of data by a type-curve can be readily embedded in an exhaustive search. That forward procedure, however, is semi-automated; it involves repeated computation of the quasi-steady flow solution, until finding an optimal pair of Kr and Ss values, according to some formal criterion of optimality, or visually. In addition, we have developed a fully automated inverse procedure for estimating the optimal hydraulic formation parameters Kr and Ss. We test and compare these two parameter estimation methods for the slug test and discuss their strengths and weaknesses. Cooper, H. H., Jr., J. D. Bredehoeft and I. S. Papadopulos. 1967

  6. Robust Automated Test Assembly for Testlet-Based Tests: An Illustration With the Analytical Reasoning Section of the LSAT

    NARCIS (Netherlands)

    Veldkamp, Bernard P.; Paap, Muirne

    2013-01-01

    In many high-stakes tests, subsets of questions (i.e., items) grouped around a common stimulus are often utilized to increase testing efficiency. These subsets of items are commonly called testlets. Since responses to items belonging to the same testlet not only depend on the test taker’s ability,

  7. 77 FR 28281 - Withdrawal of Revocation of TSCA Section 4 Testing Requirements for One High Production Volume...

    Science.gov (United States)

    2012-05-14

    ... Withdrawal of Revocation of TSCA Section 4 Testing Requirements for One High Production Volume Chemical...]amino]- (CAS No. 1324-76-1), also known as C.I. Pigment Blue 61. EPA received an adverse comment regarding C.I. Pigment Blue 61. This document withdraws the revocation of testing requirements for C.I...

  8. Crash Simulation of a Vertical Drop Test of a B737 Fuselage Section with Overhead Bins and Luggage

    Science.gov (United States)

    Jackson, Karen E.; Fasanella, Edwin L.

    2004-01-01

    The focus of this paper is to describe a crash simulation of a 30-ft/s vertical drop test of a Boeing 737 (B737) fuselage section. The drop test of the 10-ft. long fuselage section of a B737 aircraft was conducted in November of 2000 at the FAA Technical Center in Atlantic City, NJ. The fuselage section was outfitted with two different commercial overhead stowage bins. In addition, 3,229-lbs. of luggage were packed in the cargo hold to represent a maximum take-off weight condition. The main objective of the test was to evaluate the response and failure modes of the overhead stowage bins in a narrow-body transport fuselage section when subjected to a severe, but survivable, impact. A secondary objective of the test was to generate experimental data for correlation with the crash simulation. A full-scale 3-dimensional finite element model of the fuselage section was developed and a crash simulation was conducted using the explicit, nonlinear transient dynamic code, MSC.Dytran. Pre-test predictions of the fuselage and overhead bin responses were generated for correlation with the drop test data. A description of the finite element model and an assessment of the analytical/experimental correlation are presented. In addition, suggestions for modifications to the model to improve correlation are proposed.

  9. Screening Test Procedure For Long Life Single Mode Step Index Separate Confinement Heterostructure Single Quantum Well (Sinsch-Sqw) Laser Diodes

    Science.gov (United States)

    Fritz, William J.

    1989-06-01

    An experiment was conducted to establish an effective burn-in and screening procedure for long life SINSCH-SQW laser diodes. The laser diodes were grown by MOCVD and processed with 20μ wide oxide defined stripes. The devices had a high reflective back facet coating with a small etalon bonded to a passivated front facet to ensure single mode operation. The laser diodes were bonded p-side up to copper heat sinks using indium solder. A total of 48 devices were selected prior to burn-in and were operated at 200mA constant current for 2000 hours at an average heat sink temperature of 55°C. The average initial output power was 45mW per device. At the end of the test, the output powers ranged from lmW to 85mW. Most of the devices with the low final power failed catastrophically within 24 hours from the start of the test. Many laser diodes showed very little change in output power while others degraded gradually by varying amounts. Failure analysis showed that failures were facet, bulk, or heat sink related. The temporal output power degradations (i.e., gradual degradation, etc.) can be explained by the identified failure mechanisms. From the test results and failure analysis, a screening strategy based on inspection and burn-in can be devised to reject devices that may fail early. Also, improvements in processing can provide potential yield improvements. After accounting for degradation related to processing, a very long material lifetime is predicted for these SINSCH-SQW laser diodes.

  10. Thin-section CT imaging that correlates with pulmonary function tests in obstructive airway disease

    Energy Technology Data Exchange (ETDEWEB)

    Arakawa, Hiroaki, E-mail: arakawa@dokkyomed.ac.jp [Department of Radiology, Dokkyo Medical University, 880 Kita-Kobayashi, Mibu, Tochigi 321-0293 (Japan); Fujimoto, Kiminori [Department of Radiology, Kurume University School of Medicine (Japan); Fukushima, Yasutugu [Department of Pulmonary Medicine and Clinical Immunology, Dokkyo Medical University (Japan); Kaji, Yasushi [Department of Radiology, Dokkyo Medical University, 880 Kita-Kobayashi, Mibu, Tochigi 321-0293 (Japan)

    2011-11-15

    Purpose: The purpose of this study was to identify independent CT findings that correlated with pulmonary function tests (PFTs) in patients with obstructive airway diseases. Materials and methods: Sixty-eight patients with obstructive airway disease and 29 normal subjects (mean age, 52 years; 36 men and 61 women) underwent inspiratory and expiratory thin-section CT and PFTs. Patient with obvious emphysema was excluded. Two radiologists independently reviewed the images and semi-quantitatively evaluated lung attenuation (mosaic perfusion, air trapping) and airway abnormalities (extent and severity of bronchial wall thickening and bronchiectasis, bronchiolectasis or centrilobular nodules, mucous plugging). Univariate, multivariate and receiver operating characteristic (ROC) analyses were performed with CT findings and PFTs. Results: Forty-two patients showed obstructive PFTs, 26 symptomatic patients showed near-normal PFTs. On univariate analysis, air trapping and bronchial wall thickening showed highest correlation with obstructive PFTs such as FEV1.0/FVC, MMEF and FEF75 (r ranged from -0.712 to -0.782; p < 0.001), while mosaic perfusion and mucous plugging showed moderate correlation, and bronchiectasis, bronchiolectasis and nodules showed the least, but significant, correlation. Multiple logistic analyses revealed air trapping and bronchial wall thickening as the only significant independent determinants of obstructive PFTs. ROC analysis revealed the cut-off value of air trapping for obstructive PFTs to be one-third of whole lung (area under curve, 0.847). Conclusions: Our study confirmed air trapping and bronchial wall thickening are the most important observations when imaging obstructive PFTs. The cut-off value of air trapping for identifying obstructive PFTs was one-third of lung irrespective of inspiratory CT findings.

  11. 76 FR 39110 - Medicare Program; Section 3113: The Treatment of Certain Complex Diagnostic Laboratory Tests...

    Science.gov (United States)

    2011-07-05

    ... Certain Complex Diagnostic Laboratory Tests Demonstration AGENCY: Centers for Medicare & Medicaid Services... participate in the Treatment of Certain Complex Diagnostic Laboratory Tests Demonstration. The Demonstration... complex diagnostic laboratory test under the Demonstration. The statute requires a Report to Congress that...

  12. 76 FR 49491 - Medicare Program; Section 3113: The Treatment of Certain Complex Diagnostic Laboratory Tests...

    Science.gov (United States)

    2011-08-10

    ... Certain Complex Diagnostic Laboratory Tests Demonstration; Extension of the Deadline for Submission of... Complex Diagnostic Laboratory Tests Demonstration. The deadline for submitting supporting information to... Treatment of Certain Complex Diagnostic Laboratory Tests Demonstration. The Demonstration is mandated by...

  13. Development of the Porous-Slot Geometry of the NWTC Test Section

    National Research Council Canada - National Science Library

    Steinle, Frank

    1997-01-01

    .... Flow quality requirements concerning stream angle homogeneity at the outer edge of the test volume, requirements for maximum wall interference, optical access, and test volume acoustic considerations...

  14. Hydrochemistry and hydrogeologic conditions within the Hanford Site upper basalt confined aquifer system

    Energy Technology Data Exchange (ETDEWEB)

    Spane, F.A. Jr.; Webber, W.D.

    1995-09-01

    As part of the Hanford Site Ground-Water Surveillance Project, Flow System Characterization Task. Pacific Northwest Laboratory examines the potential for offsite migration of contamination within the upper basalt confined aquifer system for the US Department of Energy (DOE). As part of this activity, groundwater samples were collected over the past 2 years from selected wells completed in the upper Saddle Mountains Basalt. The hydrochemical and isotopic information obtained from these groundwater samples provides hydrologic information concerning the aquifer-flow system. Ideally, when combined with other hydrologic property information, hydrochemical and isotopic data can be used to evaluate the origin and source of groundwater, areal groundwater-flow patterns, residence and groundwater travel time, rock/groundwater reactions, and aquifer intercommunication for the upper basalt confined aquifer system. This report presents the first comprehensive Hanford Site-wide summary of hydrochemical properties for the upper basalt confined aquifer system. This report provides the hydrogeologic characteristics (Section 2.0) and hydrochemical properties (Section 3.0) for groundwater within this system. A detailed description of the range of the identified hydrochemical parameter subgroups for groundwater in the upper basalt confined aquifer system is also presented in Section 3.0. Evidence that is indicative of aquifer contamination/aquifer intercommunication and an assessment of the potential for offsite migration of contaminants in groundwater within the upper basalt aquifer is provided in Section 4.0. The references cited throughout the report are given in Section 5.0. Tables that summarize groundwater sample analysis results for individual test interval/well sites are included in the Appendix.

  15. Inertial confinement fusion

    International Nuclear Information System (INIS)

    Nuckolls, J.H.; Wood, L.L.

    1988-01-01

    Edward Teller has been a strong proponent of harnessing nuclear explosions for peaceful purposes. There are two approaches: Plowshare, which utilizes macro- explosions, and inertial confinement fusion, which utilizes microexplosions. The development of practical fusion power plants is a principal goal of the inertial program. It is remarkable that Teller's original thermonuclear problem, how to make super high yield nuclear explosions, and the opposite problem, how to make ultra low yield nuclear explosions, may both be solved by Teller's radiation implosion scheme. This paper reports on the essential physics of these two thermonuclear domains, which are separated by nine orders of magnitude in yield, provided by Teller's similarity theorem and its exceptions. Higher density makes possible thermonuclear burn of smaller masses of fuel. The leverage is high: the scale of the explosion diminishes with the square of the increase in density. The extraordinary compressibility of matter, first noticed by Teller during the Los Alamos atomic bomb program, provides an almost incredible opportunity to harness fusion. The energy density of thermonuclear fuels isentropically compressed to super high-- -densities---even to ten thousand times solid density---is small compared to the energy density at thermonuclear ignition temperatures. In small masses of fuel imploded to these super high matter densities, the energy required to achieve ignition may be greatly reduced by exploiting thermonuclear propagation from a relatively small hot spot

  16. Gravitationally confined relativistic neutrinos

    Science.gov (United States)

    Vayenas, C. G.; Fokas, A. S.; Grigoriou, D.

    2017-09-01

    Combining special relativity, the equivalence principle, and Newton’s universal gravitational law with gravitational rather than rest masses, one finds that gravitational interactions between relativistic neutrinos with kinetic energies above 50 MeV are very strong and can lead to the formation of gravitationally confined composite structures with the mass and other properties of hadrons. One may model such structures by considering three neutrinos moving symmetrically on a circular orbit under the influence of their gravitational attraction, and by assuming quantization of their angular momentum, as in the Bohr model of the H atom. The model contains no adjustable parameters and its solution, using a neutrino rest mass of 0.05 eV/c2, leads to composite state radii close to 1 fm and composite state masses close to 1 GeV/c2. Similar models of relativistic rotating electron - neutrino pairs give a mass of 81 GeV/c2, close to that of W bosons. This novel mechanism of generating mass suggests that the Higgs mass generation mechanism can be modeled as a latent gravitational field which gets activated by relativistic neutrinos.

  17. Thermostating highly confined fluids.

    Science.gov (United States)

    Bernardi, Stefano; Todd, B D; Searles, Debra J

    2010-06-28

    In this work we show how different use of thermostating devices and modeling of walls influence the mechanical and dynamical properties of confined nanofluids. We consider a two dimensional fluid undergoing Couette flow using nonequilibrium molecular dynamics simulations. Because the system is highly inhomogeneous, the density shows strong fluctuations across the channel. We compare the dynamics produced by applying a thermostating device directly to the fluid with that obtained when the wall is thermostated, considering also the effects of using rigid walls. This comparison involves an analysis of the chaoticity of the fluid and evaluation of mechanical properties across the channel. We look at two thermostating devices with either rigid or vibrating atomic walls and compare them with a system only thermostated by conduction through vibrating atomic walls. Sensitive changes are observed in the xy component of the pressure tensor, streaming velocity, and density across the pore and the Lyapunov localization of the fluid. We also find that the fluid slip can be significantly reduced by rigid walls. Our results suggest caution in interpreting the results of systems in which fluid atoms are thermostated and/or wall atoms are constrained to be rigid, such as, for example, water inside carbon nanotubes.

  18. Operational technology for greater confinement disposal

    International Nuclear Information System (INIS)

    Dickman, P.T.; Vollmer, A.T.; Hunter, P.H.

    1984-12-01

    Procedures and methods for the design and operation of a greater confinement disposal facility using large-diameter boreholes are discussed. It is assumed that the facility would be located at an operating low-level waste disposal site and that only a small portion of the wastes received at the site would require greater confinement disposal. The document is organized into sections addressing: facility planning process; facility construction; waste loading and handling; radiological safety planning; operations procedures; and engineering cost studies. While primarily written for low-level waste management site operators and managers, a detailed economic assessment section is included that should assist planners in performing cost analyses. Economic assessments for both commercial and US government greater confinement disposal facilities are included. The estimated disposal costs range from $27 to $104 per cubic foot for a commercial facility and from $17 to $60 per cubic foot for a government facility. These costs are based on average site preparation, construction, and waste loading costs for both contact- and remote-handled wastes. 14 figures, 22 tables

  19. Non-resonant Nanoscale Extreme Light Confinement

    Energy Technology Data Exchange (ETDEWEB)

    Subramania, Ganapathi Subramanian [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Huber, Dale L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    A wide spectrum of photonics activities Sandia is engaged in such as solid state lighting, photovoltaics, infrared imaging and sensing, quantum sources, rely on nanoscale or ultrasubwavelength light-matter interactions (LMI). The fundamental understanding in confining electromagnetic power and enhancing electric fields into ever smaller volumes is key to creating next generation devices for these programs. The prevailing view is that a resonant interaction (e.g. in microcavities or surface-plasmon polaritions) is necessary to achieve the necessary light confinement for absorption or emission enhancement. Here we propose new paradigm that is non-resonant and therefore broadband and can achieve light confinement and field enhancement in extremely small areas [~(λ/500)^2 ]. The proposal is based on a theoretical work[1] performed at Sandia. The paradigm structure consists of a periodic arrangement of connected small and large rectangular slits etched into a metal film named double-groove (DG) structure. The degree of electric field enhancement and power confinement can be controlled by the geometry of the structure. The key operational principle is attributed to quasistatic response of the metal electrons to the incoming electromagnetic field that enables non-resonant broadband behavior. For this exploratory LDRD we have fabricated some test double groove structures to enable verification of quasistatic electronic response in the mid IR through IR optical spectroscopy. We have addressed some processing challenges in DG structure fabrication to enable future design of complex sensor and detector geometries that can utilize its non-resonant field enhancement capabilities.].

  20. Confinement less spectral behavior in hollow-core Bragg fibers

    DEFF Research Database (Denmark)

    Foroni, M.; Passaro, D.; Poli, F.

    2007-01-01

    The influence of each cross-section geometric parameter on hollow-core Bragg fiber guiding properties has been numerically investigated. Fabricated fibers have been modeled, giving insight into the spectral behavior of the confinement loss. It has been verified that, by changing the amount...... of silica and air in the fiber cladding, it is possible to change the reflection conditions undergone by the field within the core, thus shifting the confinement loss spectrum....

  1. Factors Affecting Result in Chinese Proficiency Test (HSK Level 6: Reading Section and Preparation Strategies

    Directory of Open Access Journals (Sweden)

    Sri Haryanti

    2013-11-01

    Full Text Available Chinese Proficiency Test (HSK is an internationally standardized exam which tests and rates Chinese language proficiency. The highest level in this test is level 6. The writing part of the test consists of 3 (three parts, namely, (1 listening, (2 reading, (3 writing. Furthermore, the reading part is made of 4 components. Level 6 of this test implies a high degree of difficulty. This paper specifically looked on how to prepare effectively for participants to be able to work on the reading part in order to achieve best result. This article used the methods of literature review and observational study as well as field research and would also incorporate the author’s personal experience in taking the test into recommending strategies for doing the reading part in a level 6 HSK test. Finally, research suggested several techniques and tips that might assist participants in achieving maximum scores in handling the reading part of level 6 HSK test.

  2. Behavior of Confined Columns under Different Techniques

    OpenAIRE

    Mostafa Osman; Ata El-Kareim Shoeib Soliman

    2015-01-01

    Since columns are the most important elements of the structures, failure of one column in a critical location can cause a progressive collapse. In this respect, the repair and strengthening of columns is a very important subject to reduce the building failure and to keep the columns capacity. Twenty columns with different parameters is tested and analysis. Eleven typical confined reinforced concrete (RC) columns with different types of techniques are assessment. And also,...

  3. Equity in HIV testing: evidence from a cross-sectional study in ten Southern African countries

    Directory of Open Access Journals (Sweden)

    Mitchell Steven

    2010-09-01

    Full Text Available Abstract Background HIV testing with counseling is an integral component of most national HIV and AIDS prevention strategies in southern Africa. Equity in testing implies that people at higher risk for HIV such as women; those who do not use condoms consistently; those with multiple partners; those who have suffered gender based violence; and those who are unable to implement prevention choices (the choice-disabled are tested and can have access to treatment. Methods We conducted a household survey of 24,069 people in nationally stratified random samples of communities in Botswana, Lesotho, Malawi, Mozambique, Namibia, South Africa, Swaziland, Tanzania, Zambia, and Zimbabwe. We asked about testing for HIV in the last 12 months, intention to test, and about HIV risk behaviour, socioeconomic indicators, access to information, and attitudes related to stigma. Results Across the ten countries, seven out of every ten people said they planned to have an HIV test but the actual proportion tested in the last 12 months varied from 24% in Mozambique to 64% in Botswana. Generally, people at higher risk of HIV were not more likely to have been tested in the last year than those at lower risk, although women were more likely than men to have been tested in six of the ten countries. In Swaziland, those who experienced partner violence were more likely to test, but in Botswana those who were choice-disabled for condom use were less likely to be tested. The two most consistent factors associated with HIV testing across the countries were having heard about HIV/AIDS from a clinic or health centre, and having talked to someone about HIV and AIDS. Conclusions HIV testing programmes need to encourage people at higher risk of HIV to get tested, particularly those who do not interact regularly with the health system. Service providers need to recognise that some people are not able to implement HIV preventive actions and may not feel empowered to get themselves

  4. A cross-sectional study of the association between mobility test performance and personality among older adults

    OpenAIRE

    Agmon, Maayan; Armon, Galit

    2016-01-01

    Background Falls among the elderly are a major public health challenge. The Timed-Up and Go (TUG) test is commonly used to identify older adults with mobility limitations. This study explored the association between TUG test results and personality among community-dwelling older adults. Methods This cross-sectional study included 85 older adults. Personality was evaluated with the Five Factor Model. Times to complete the TUG as a single task (TUGST) alone and also with an additional cognitive...

  5. Alternative approaches to plasma confinement

    Science.gov (United States)

    Roth, J. R.

    1978-01-01

    The paper discusses 20 plasma confinement schemes each representing an alternative to the tokamak fusion reactor. Attention is given to: (1) tokamak-like devices (TORMAC, Topolotron, and the Extrap concept), (2) stellarator-like devices (Torsatron and twisted-coil stellarators), (3) mirror machines (Astron and reversed-field devices, the 2XII B experiment, laser-heated solenoids, the LITE experiment, the Kaktus-Surmac concept), (4) bumpy tori (hot electron bumpy torus, toroidal minimum-B configurations), (5) electrostatically assisted confinement (electrostatically stuffed cusps and mirrors, electrostatically assisted toroidal confinement), (6) the Migma concept, and (7) wall-confined plasmas. The plasma parameters of the devices are presented and the advantages and disadvantages of each are listed.

  6. Assessing confinement in coastal lagoons.

    Science.gov (United States)

    Canu, Donata Melaku; Solidoro, Cosimo; Umgiesser, Georg; Cucco, Andrea; Ferrarin, Christian

    2012-11-01

    Measures of transport scale in aquatic systems can contribute to the formulation of definitions of indicators of the system's ecological properties. This paper addresses confinement, a specific transport scale proposed by biological scientists as a parameter that can capture and synthesize the principal properties that determine the spatial structure of biological communities in transitional environments. Currently, there is no direct experimental measure of confinement. In this study, a methodology based on the accumulation rate within a lagoon of a passive tracer of marine origin is proposed, the influences of different factors in the calculation of confinement are analyzed, and general recommendations are derived. In particular, we analyze the spatial and the temporal variability of confinement and its sensitivity to the seasonal variability of climatic forcing, the inputs from rivers and the parameterization of the tidal exchanges. The Lagoon of Venice is used as a case study. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Impurities confined in quantum structures

    CERN Document Server

    Holtz, Per Olof

    2004-01-01

    The introduction of impurities, even in very small concentrations, in a semiconductor can change its optical and electrical properties entirely. This attribute of the semiconductor is utilized in the manifoldness of their applications. In this book, the progress on elucidating the physical properties of impurities confined in quantum structures are reviewed with an emphasis on the experimental aspects. The major results of various kinds of characterization, such as infrared spectroscopy, Raman measurements, luminescence characterization, perturbation spectroscopy and dynamical studies of the confined impurities are reviewed, but also the theoretical basis to calculate the electronic structure of the confined donors and acceptors are presented. This monograph also describes more specific aspects of the confined impurities such as the properties in the high doping regime and the effects of hydrogen passivation.

  8. The relationship between Test Takers’ Multiple Intelligences and Their Performance on the Reading Sections of TOEFL and IELTS

    Directory of Open Access Journals (Sweden)

    Minoo Alemi

    2010-04-01

    Full Text Available The present study aimed at investigating the hypothetical relationship between the multiple intelligences of test takers and their performance on the reading sections of TOEFL and IELTS. Howard Gardner’s theory of multiple intelligences suggests that intelligence is not a single and solely inborn capacity, rather a multiple construct which is only partly genetic, and can be crystallized or paralyzed over one’s lifetime. Based on the theory, there are eight types of intelligence: linguistic, mathematical, musical, bodily, spatial, intrapersonal, interpersonal and naturalist, but the list is not exhaustive. The multiple intelligences of test takers were estimated by means of MIDAS, the Multiple Intelligences Developmental Assessment Scales, developed by Shearer (1994. Subsequently, the bias detection for the reading section of TOEFL was carried out on 90 participants, and this subtest was found to correlate positively with linguistic and logical intelligences. By the same token, 89 out of the 163 participants in the study were included in the analysis of the relationship between the multiple intelligences of test takers and their performance on the reading section of IELTS, and this test proved biased toward linguistic and spatial intelligences. The implications concern the inadequacy of the definition of language proficiency .Moreover, Measurement-Driven Instruction courses and preparatory materials of the two proficiency tests, TOEFL and IELTS, can benefit from the results of the study by being designed in such a way as to represent the intelligences which are positively correlated with performance on the tests in question.

  9. Compression Tests on Circular Cylinders Stiffened Longitudinally by Closely Spaced Z-Section Stringers

    Science.gov (United States)

    Peterson, James P.; Dow, Marvin B.

    1959-01-01

    Six circular cylinders stiffened longitudinally by closely spaced Z-section stringers were loaded to failure in compression. The results obtained are presented and compared with available theoretical results for the buckling of orthotropic cylinders. The results indicate that the large disparity that exists between theory and experiment for unstiffened compression cylinders may be significantly smaller for stiffened cylinders.

  10. Unit root tests for cross-sectionally dependent panels : The influence of observed factors

    NARCIS (Netherlands)

    Becheri, I.G.; Drost, F.C.; van den Akker, R.

    This paper considers a heterogeneous panel unit root model with cross-sectional dependence generated by a factor structure—the factor common to all units being an observed covariate. The model is shown to be Locally Asymptotically Mixed Normal (LAMN), with the random part of the limiting Fisher

  11. Numerical prediction of shock induced oscillations over a 2D airfoil: Influence of turbulence modelling and test section walls

    International Nuclear Information System (INIS)

    Thiery, Mylene; Coustols, Eric

    2006-01-01

    The present study deals with recent numerical results from on-going research conducted at ONERA/DMAE regarding the prediction of transonic flows, for which shock wave/boundary layer interaction is important. When this interaction is strong enough (M ≥ 1.3), shock induced oscillations (SIO) appear at the suction side of the airfoil and lead to the formation of unsteady separated areas. The main issue is then to perform unsteady computations applying appropriate turbulence modelling and relevant boundary conditions with respect to the test case. Computations were performed with the ONERA elsA software and the URANS-type approach, closure relationships being achieved from transport-equation models. Applications are provided for the OAT15A airfoil data base, well documented for unsteady CFD validation (mean and r.m.s. pressure, phase-averaged LDA data, ...). In this paper, the capabilities of turbulence models are evaluated with two 2D URANS strategies, under free-stream or confined conditions. The latter takes into account the adaptive upper and lower wind-tunnel walls. A complete 3D URANS simulation was then performed to demonstrate the real impact of all lateral wind-tunnel walls on such a flow

  12. Infrared slavery and quark confinement

    CERN Document Server

    Alabiso, C

    1976-01-01

    The question is considered of whether the so-called infrared slavery mechanism as, e.g., being manifest in non-Abelian gauge theories, necessarily confines quarks. Making a specific ansatz for the long- range forces, the Schwinger-Dyson equation is solved for the quark Green function. Besides having a confining solution, it appears that quarks may by-pass the long-range forces and be produced. (20 refs).

  13. Impact Testing and Simulation of a Crashworthy Composite Fuselage Section with Energy-Absorbing Seats and Dummies

    Science.gov (United States)

    Fasanella, Edwin L.; Jackson, Karen E.

    2002-01-01

    A 25-ft/s vertical drop test of a composite fuselage section was conducted with two energy-absorbing seats occupied by anthropomorphic dummies to evaluate the crashworthy features of the fuselage section and to determine its interaction with the seats and dummies. The 5-ft diameter fuselage section consists of a stiff structural floor and an energy-absorbing subfloor constructed of Rohacel foam blocks. The experimental data from this test were analyzed and correlated with predictions from a crash simulation developed using the nonlinear, explicit transient dynamic computer code, MSC.Dytran. The anthropomorphic dummies were simulated using the Articulated Total Body (ATB) code, which is integrated into MSC.Dytran.

  14. Testing for Helicobacter pylori in dyspeptic patients suspected of peptic ulcer disease in primary care: cross sectional study

    NARCIS (Netherlands)

    Weijnen, C. F.; Numans, M. E.; de Wit, N. J.; Smout, A. J.; Moons, K. G.; Verheij, T. J.; Hoes, A. W.

    2001-01-01

    OBJECTIVES: To develop an easily applicable diagnostic scoring method to determine the presence of peptic ulcers in dyspeptic patients in a primary care setting; to evaluate whether Helicobacter pylori testing adds value to history taking. Design: Cross sectional study. SETTING: General

  15. 78 FR 27860 - Revocation of TSCA Section 4 Testing Requirements for One High Production Volume Chemical Substance

    Science.gov (United States)

    2013-05-13

    ... Revocation of TSCA Section 4 Testing Requirements for One High Production Volume Chemical Substance AGENCY... Production Volume (HPV) chemical substance, benzenesulfonic acid, [[4-[[4-(phenylamino)phenyl][4-(phenylimino)-2,5- cyclohexadien-1-ylidene]methyl]phenyl]amino]- (CAS No. 1324-76-1), also known as C.I. Pigment...

  16. Cross-sectional evaluation of an internet-based hearing screening test in an occupational setting

    NARCIS (Netherlands)

    Sheikh Rashid, Marya; Leensen, Monique Cj; de Laat, Jan Apm; Dreschler, Wouter A.

    2017-01-01

    Objectives The Occupational Earcheck (OEC) is an online internet test to detect high-frequency hearing loss for the purposes of occupational hearing screening. In this study, we evaluated the OEC in an occupational setting in order to assess test sensitivity, specificity, and validity. Methods A

  17. Safety measures for integrity test apparatus for IS process. Sulfuric acid decomposition section

    International Nuclear Information System (INIS)

    Noguchi, Hiroki; Kubo, Shinji; Iwatsuki, Jin; Onuki, Kaoru

    2013-07-01

    Hazardous substances such as sulfuric acid, sulfur dioxide and hydrogen iodide acid are employed in thermochemical Iodine-Sulfur (IS) process. It is necessary to take safety measure against workers and external environments to study experimentally on IS process. Presently we have been conducting to verify the soundness of main components made of engineering material in actual corrosive condition. An integrity test apparatus for the components of sulfuric acid decomposition was set up. We will use the hazardous substances such as sulfuric acid and sulfur dioxide and perform the experiment in pressurized condition in this integrity test. Safety measures for the test apparatus, operation and abnormal situation were considered prior to starting the test. This report summarized the consideration results for the safety measures on the integrity test apparatus for the components of sulfuric acid decomposition. (author)

  18. A new laser reflectance system capable of measuring changing cross-sectional area of soft tissues during tensile testing.

    Science.gov (United States)

    Pokhai, Gabriel G; Oliver, Michele L; Gordon, Karen D

    2009-09-01

    Determination of the biomechanical properties of soft tissues such as tendons and ligaments is dependent on the accurate measurement of their cross-sectional area (CSA). Measurement methods, which involve contact with the specimen, are problematic because soft tissues are easily deformed. Noncontact measurement methods are preferable in this regard, but may experience difficulty in dealing with the complex cross-sectional shapes and glistening surfaces seen in soft tissues. Additionally, existing CSA measurement systems are separated from the materials testing machine, resulting in the inability to measure CSA during testing. Furthermore, CSA measurements are usually made in a different orientation, and with a different preload, prior to testing. To overcome these problems, a noncontact laser reflectance system (LRS) was developed. Designed to fit in an Instron 8872 servohydraulic test machine, the system measures CSA by orbiting a laser transducer in a circular path around a soft tissue specimen held by tissue clamps. CSA measurements can be conducted before and during tensile testing. The system was validated using machined metallic specimens of various shapes and sizes, as well as different sizes of bovine tendons. The metallic specimens could be measured to within 4% accuracy, and the tendons to within an average error of 4.3%. Statistical analyses showed no significant differences between the measurements of the LRS and those of the casting method, an established measurement technique. The LRS was successfully used to measure the changing CSA of bovine tendons during uniaxial tensile testing. The LRS developed in this work represents a simple, quick, and accurate way of reconstructing complex cross-sectional profiles and calculating cross-sectional areas. In addition, the LRS represents the first system capable of automatically measuring changing CSA of soft tissues during tensile testing, facilitating the calculation of more accurate biomechanical properties.

  19. Improved confinement in L-mode JET plasmas

    International Nuclear Information System (INIS)

    Jones, T.T.C.; Balet, B.; Bhatnagar, V.; Bures, M.; Campbell, D.J.; Christiansen, J.P.; Cordey, J.G.; Core, W.F.; Corti, S.; Costley, A.E.; Cottrell, G.A.; Edwards, A.; Ehrenberg, J.; Jacquinot, J.; Lallia, P.; Lomas, P.J.; Lowry, C.; Malacarne, M.; Muir, D.G.; Nave, M.F.; Nielsen, P.; Sack, C.; Sadler, G.; Start, D.F.H.; Taroni, A.; Thomas, P.R.; Thomsen, K.

    1989-01-01

    The JET confinement data show considerable variations of stored plasma energy W (thermal + fast ions) at fixed input power P, plasma current I, toroidal field B and plasma configuration C. The data on confinement properties, e.g. the confinement time τ E or its incremental value τ E (inc), derived from variations of P at fixed I, B, C thus exhibit scatter which makes the scaling of τ E with P, I, B, C difficult to establish. The effects from sawteeth, from variations in the power deposition profiles and from plasma edge physics on confinement do not depend on P, I, B, C in any simple way which would permit a deduced scaling law to be identified with a single (or more) physics loss mechanism(s). In this paper we examine the response of confinement to variations in plasma configuration at fixed I and B (3 MA and 3 T). Results from global and local transport analysis are discussed in sections 2 and 3; section 4 describes the role of fast ions produced by ICRF and NBI heating. High confinement in the L-mode regime at increased plasma currents up to 6 MA is also studied, in particular the effects from sawteeth on stored energy W. Such effects increase with current and presently only predictive transport studies (section 5) can estimate what may be achieved at high current without sawteeth effects. The predictive studies also assess the benefits which may arise from an increase of the neutral beam energy at high plasma currents (section 6). The conclusions are based on extensive study of data from JET pulses with up to 14 MW of ICRH, 21 MW of NBI and 6 MW of ohmic power. None of the pulses included in the study show the sudden reduction of D α emission characteristic of the L to H mode transition of confinement. 7 refs., 4 figs

  20. Construction of PWR nuclear cross sections for transient calculations. Test of the ANTI program against TWODIM

    International Nuclear Information System (INIS)

    Thorlaksen, B.

    1981-05-01

    Nuclear cross sections for fuel assemblies of the more recent Westinghouse designs, representing two different PWR reactor cores, are calculated as functions of average fuel temperature, moderator density, and moderator poison concentration. The cross-section functions are verified by referring to Westinghouse power-shape calculations and other analysis. Computations on the side reflector resulted in significantly higher albedo values than used previously for BWR's in similar nodal codes. This led to an investigation of the influence of the internodal coupling coefficients on the power shape. It is concluded that the calculated power shape is strongly dependent, on the choise of coupling coefficients. However, it is shown that ''the correct'' set of coupling coefficients depends mostly on the nodal configuration, and that it is fairly independent of the power condition. (author)

  1. Test anxiety and self-esteem in senior high school students: a cross-sectional study.

    Science.gov (United States)

    Sarı, Seda Aybüke; Bilek, Günal; Çelik, Ekrem

    2018-02-01

    In this study, it is aimed to determine the level of test anxiety and self-esteem in the high school students preparing for the university exam in Bitlis, Turkey, and to investigate the effect of test anxiety on self-esteem. Seven-hundred and twenty-four high school students who were preparing for the university entrance examination in Bitlis participated in the study. A questionnaire which includes socio-demographic data form, Rosenberg Self-Esteem Scale and Revised Test Anxiety Scale was prepared as an e-questionnaire for the students to fill easily and uploaded to the Bitlis State Hospital's website. Schools were called and informed for the students to fill out the e-questionnaire on the Internet. The most important findings from our study are that gender is influential on test anxiety and self-esteem score and test anxiety level are negatively correlated. It was observed that female students had more test anxiety than male students and those who had higher self-esteem had less test anxiety. Consequently, our study shows that university entrance examination creates anxiety on students and reduces self-esteem, especially in female students.

  2. Evaluation of Precast Panels for Airfield Pavement Repair. Phase 1: System Optimization and Test Section Construction

    Science.gov (United States)

    2013-06-01

    the section followed by a double coating of white pigmented membrane forming curing compound. The average 28-day compressive and flexural strength...cover formed faces.  This method can discolor or stain the surface and has the potential to leave wrinkle marks when removed.  Apply burlap once...to mark the locations for the dowel receptacles. Fully paint ERDC/GSL TR-13-24 159 the areas in between the teeth to indicate what will be

  3. Comparative study on the mechanical mechanism of confined concrete supporting arches in underground engineering.

    Science.gov (United States)

    Lv, Zhijin; Qin, Qian; Jiang, Bei; Luan, Yingcheng; Yu, Hengchang

    2018-01-01

    In order to solve the supporting problem in underground engineering with high stress, square steel confined concrete (SQCC) supporting method is adopted to enhance the control on surrounding rocks, and the control effect is remarkable. The commonly used cross section shapes of confined concrete arch are square and circular. At present, designers have no consensus on which kind is more proper. To search for the answer, this paper makes an analysis on the mechanical properties of the two shapes of the cross-sections. A full-scale indoor comparative test was carried out on the commonly used straight-wall semi-circular SQCC arch and circular steel confined concrete arch (CCC arch). This test is based on self-developed full-scale test system for confined concrete arch. Our research, combining with the numerical analysis, shows: (1) SQCC arch is consistent with CCC arch in the deformation and failure mode. The largest damages parts are at the legs of both of them. (2) The SQCC arch's bearing capability is 1286.9 kN, and the CCC arch's ultimate bearing capability is 1072.4kN. Thus, the SQCC arch's bearing capability is 1.2 times that of the CCC arch. (3) The arches are subjected to combined compression and bending, bending moment is the main reason for the arch failure. The section moment of inertia of SQCC arch is 1.26 times of that of CCC arch, and the former is better than the latter in bending performance. The ultimate bearing capacity is positively correlated with the size of the moment of inertia. Based on the above research, the engineering suggestions are as follows: (1) To improve the bearing capacity of the arch, the cross-sectional shape of the chamber should be optimized and the arch bearing mode changed accordingly. (2) The key damaged positions, such as the arch leg, should be reinforced, optimizing the state of force on the arch. SQCC arches should be used for supporting in underground engineering, which is under stronger influence of the bending moment and

  4. Comparative study on the mechanical mechanism of confined concrete supporting arches in underground engineering.

    Directory of Open Access Journals (Sweden)

    Zhijin Lv

    Full Text Available In order to solve the supporting problem in underground engineering with high stress, square steel confined concrete (SQCC supporting method is adopted to enhance the control on surrounding rocks, and the control effect is remarkable. The commonly used cross section shapes of confined concrete arch are square and circular. At present, designers have no consensus on which kind is more proper. To search for the answer, this paper makes an analysis on the mechanical properties of the two shapes of the cross-sections. A full-scale indoor comparative test was carried out on the commonly used straight-wall semi-circular SQCC arch and circular steel confined concrete arch (CCC arch. This test is based on self-developed full-scale test system for confined concrete arch. Our research, combining with the numerical analysis, shows: (1 SQCC arch is consistent with CCC arch in the deformation and failure mode. The largest damages parts are at the legs of both of them. (2 The SQCC arch's bearing capability is 1286.9 kN, and the CCC arch's ultimate bearing capability is 1072.4kN. Thus, the SQCC arch's bearing capability is 1.2 times that of the CCC arch. (3 The arches are subjected to combined compression and bending, bending moment is the main reason for the arch failure. The section moment of inertia of SQCC arch is 1.26 times of that of CCC arch, and the former is better than the latter in bending performance. The ultimate bearing capacity is positively correlated with the size of the moment of inertia. Based on the above research, the engineering suggestions are as follows: (1 To improve the bearing capacity of the arch, the cross-sectional shape of the chamber should be optimized and the arch bearing mode changed accordingly. (2 The key damaged positions, such as the arch leg, should be reinforced, optimizing the state of force on the arch. SQCC arches should be used for supporting in underground engineering, which is under stronger influence of the

  5. A Review of Quantum Confinement

    Science.gov (United States)

    Connerade, Jean-Patrick

    2009-12-01

    A succinct history of the Confined Atom problem is presented. The hydrogen atom confined to the centre of an impenetrable sphere counts amongst the exactly soluble problems of physics, alongside much more noted exact solutions such as Black Body Radiation and the free Hydrogen atom in absence of any radiation field. It shares with them the disadvantage of being an idealisation, while at the same time encapsulating in a simple way particular aspects of physical reality. The problem was first formulated by Sommerfeld and Welker [1]—henceforth cited as SW—in connection with the behaviour of atoms at very high pressures, and the solution was published on the occasion of Pauli's 60th birthday celebration. At the time, it seemed that there was not much other connection with physical reality beyond a few simple aspects connected to the properties of atoms in solids, for which more appropriate models were soon developed. Thus, confined atoms attracted little attention until the advent of the metallofullerene, which provided the first example of a confined atom with properties quite closely related to those originally considered by SW. Since then, the problem has received much more attention, and many more new features of quantum confinement, quantum compression, the quantum Faraday cage, electronic reorganisation, cavity resonances, etc have been described, which are relevant to real systems. Also, a number of other situations have been uncovered experimentally to which quantum confinement is relevant. Thus, studies of the confined atom are now more numerous, and have been extended both in terms of the models used and the systems to which they can be applied. Connections to thermodynamics are explored through the properties of a confined two-level atom adapted from Einstein's celebrated model, and issues of dynamical screening of electromagnetic radiation by the confining shell are discussed in connection with the Faraday cage produced by a confining conducting shell

  6. Visualization of flaws within heavy section ultrasonic test blocks using high energy computed tomography

    International Nuclear Information System (INIS)

    House, M.B.; Ross, D.M.; Janucik, F.X.; Friedman, W.D.; Yancey, R.N.

    1996-05-01

    The feasibility of high energy computed tomography (9 MeV) to detect volumetric and planar discontinuities in large pressure vessel mock-up blocks was studied. The data supplied by the manufacturer of the test blocks on the intended flaw geometry were compared to manual, contact ultrasonic test and computed tomography test data. Subsequently, a visualization program was used to construct fully three-dimensional morphological information enabling interactive data analysis on the detected flaws. Density isosurfaces show the relative shape and location of the volumetric defects within the mock-up blocks. Such a technique may be used to qualify personnel or newly developed ultrasonic test methods without the associated high cost of destructive evaluation. Data is presented showing the capability of the volumetric data analysis program to overlay the computed tomography and destructive evaluation (serial metallography) data for a direct, three-dimensional comparison

  7. Predictors of HIV Testing among Youth in Sub-Saharan Africa: A Cross-Sectional Study.

    Science.gov (United States)

    Asaolu, Ibitola O; Gunn, Jayleen K; Center, Katherine E; Koss, Mary P; Iwelunmor, Juliet I; Ehiri, John E

    2016-01-01

    In spite of a high prevalence of HIV infection among adolescents and young adults in sub-Saharan Africa, uptake of HIV testing and counseling among youth in the region remains sub-optimal. The objective of this study was to assess factors that influence uptake of HIV testing and counseling among youth aged 15-24 years in sub-Saharan Africa. This study used the Demographic and Health Survey (DHS) data from countries that represent four geographic regions of sub-Saharan Africa: Congo (Brazzaville), representing central Africa (DHS 2011-2012); Mozambique, representing southern Africa (DHS 2011); Nigeria, representing western Africa (DHS 2013); and Uganda, representing eastern Africa (DHS 2011). Analyses were restricted to 23,367 male and female respondents aged 15-24 years with complete data on the variables of interest. Chi-square tests and logistic regression models were used to assess predictors of HIV testing. Statistical significance was set at psub-Saharan Africa for HIV testing continues to be a challenge. Public health programs that seek to increase HIV counseling and testing among youth should pay particular attention to efforts that target high-risk subpopulations of youth. The results further suggest that these initiatives would be strengthened by including strategies to increase HIV comprehensive knowledge.

  8. Dynamic impact testing on post-tensioned steel rectangular hollow sections; An investigation into the "compression-softening" effect

    Science.gov (United States)

    Noble, Darragh; Nogal, Maria; O`Connor, Alan; Pakrashi, Vikram

    2015-10-01

    This paper describes the results of dynamic impact testing on externally axially loaded steel rectangular hollow sections (RHSs) and compares the response to that of externally post-tensioned steel RHSs. Both the fundamental natural bending frequency of the beam sections and the corresponding damping ratios have been calculated from the measured dynamic response of the beam to a series of impact hammer strikes. The validity of the "compression-softening" effect for post-tensioned sections is tested. The implications of the research are vast, as currently, there is significant disagreement among researchers about the effect of pre- and post-tensioning loads on the dynamic characteristics of structures. The fundamental bending frequencies have been calculated and corresponding damping ratio have been calculated from dynamic test results for each axial load level. The bending frequencies have been calculated repeatedly while changing the axial load level and the subsequent changes in both frequency and damping ratio, with increasing axial load level have been analysed to determine if the results are statistically significant. It has been determined that "compression softening" theory is not valid for pre- or post-tensioned sections.

  9. Gas solubility in hydrophobic confinement.

    Science.gov (United States)

    Luzar, Alenka; Bratko, Dusan

    2005-12-01

    Measured forces between apolar surfaces in water have often been found to be sensitive to exposure to atmospheric gases despite low gas solubilities in bulk water. This raises questions as to how significant gas adsorption is in hydrophobic confinement, whether it is conducive to water depletion at such surfaces, and ultimately if it can facilitate the liquid-to-gas phase transition in the confinement. Open Ensemble molecular simulations have been used here to determine saturated concentrations of atmospheric gases in water-filled apolar confinements as a function of pore width at varied gas fugacities. For paraffin-like confinements of widths barely exceeding the mechanical instability threshold (spinodal) of the liquid-to-vapor transition of confined water (aqueous film thickness between three and four molecular diameters), mean gas concentrations in the pore were found to exceed the bulk values by a factor of approximately 30 or approximately 15 in cases of N2 and CO2, respectively. At ambient conditions, this does not result in visible changes in the water density profile next to the surfaces. Whereas the barrier to capillary evaporation has been found to decrease in the presence of dissolved gas (Leung, K.; Luzar, A.; and Bratko, D. Phys. Rev. Lett. 2003, 90, 065502), gas concentrations much higher than those observed at normal atmospheric conditions would be needed to produce noticeable changes in the kinetics of capillary evaporation. In simulations, dissolved gas concentrations corresponding to fugacities above approximately 40 bar for N2, or approximately 2 bar for CO2, were required to trigger expulsion of water from a hydrocarbon slit as narrow as 1.4 nm. For nanosized pore widths corresponding to the mechanical instability threshold or above, no significant coupling between adsorption layers at opposing confinement walls was observed. This finding explains the approximately linear increase in gas solubility with inverse confinement width and the

  10. Experimental test of the non-reproducibility of cross sections in dissipative reactions

    CERN Document Server

    Dong Yu Chuan; Tian Wen Dong; Li Song Lin; Li Zhi Chang; Lu Xiu Qin; Zhao Kui; Fu Chang Bo; Liu Jian Cheng; Jiang Hua; Hu Gui Qing

    2002-01-01

    Two independent measurements of cross sections for the sup 1 sup 9 F + sup 9 sup 3 Nb dissipative heavy ion collisions have been performed at incident energies from 100 to 108 MeV in steps of 250 keV. In the two measurements, two independently prepared targets were used. All other experimental conditions were identical in both experiments. The data indicate that non-reproducibility of the non-self-averaging oscillation is yielded in the two measurements. This supports the recent theoretical predictions of spontaneous coherence, slow phase randomization and extreme sensitivity in highly excited complex quantum systems

  11. Testing of cross-section functionals in the unresolved resonance region

    International Nuclear Information System (INIS)

    Koshcheev, V.N.; Krivtsov, A.S.; Sinitsa, V.V.; Ukraintsev, V.F.

    1994-01-01

    The results of a comparison of the GRUCON, MMK and NJOY data processing codes in the treatment of evaluated neutron data in the unresolved resonance region are presented. The sets of average resonance parameters of 238 U and 239 Pu isotopes, which have been published by Munos-Cobos et al., and Ribon et al., were used in this exercise. Average cross-sections, self-shielding factors and Doppler broadening self-shielding factors are compared with the original results presented by the above-mentioned authors. Conclusions regarding the reliability of the neutron data processing codes are made. (author). 6 refs, 7 tabs

  12. Singularity confinement for maps with the Laurent property

    International Nuclear Information System (INIS)

    Hone, A.N.W.

    2007-01-01

    The singularity confinement test is very useful for isolating integrable cases of discrete-time dynamical systems, but it does not provide a sufficient criterion for integrability. Quite recently a new property of the bilinear equations appearing in discrete soliton theory has been noticed: The iterates of such equations are Laurent polynomials in the initial data. A large class of non-integrable mappings of the plane are presented which both possess this Laurent property and have confined singularities

  13. A Cross-Sectional Survey of HIV Testing and Prevalence in Twelve Brazilian Correctional Facilities.

    Directory of Open Access Journals (Sweden)

    Renata Viebrantz Enne Sgarbi

    Full Text Available Prior studies have reported higher HIV prevalence among prisoners than the general population in Brazil, but data have been derived from single prisons. The aim of this study was to evaluate HIV testing practices, prevalence and linkage to care among inmates in a network of 12 prisons.We administered a questionnaire to a population-based sample of inmates from 12 prisons in Central-West Brazil and collected sera for HIV and syphilis testing from January to December 2013. We evaluated factors associated with HIV testing and infection using multivariable logistic regression models. Six months after HIV testing, we assessed whether each HIV-infected prisoner was engaged in clinical care and whether they had started antiretroviral therapy.We recruited 3,362 inmates, of whom 2,843 (85% were men from 8 prisons, and 519 (15% were women from 4 prisons. Forty-five percent of participants reported never having been tested for HIV previously. In multivariable analysis, the variables associated with previous HIV testing were lack of a stable partner (adjusted odds ratio [AOR]: 1.38; 95% CI: 1.18-1.60, completed more than four years of schooling (AOR 1.40; 95% CI: 1.20-1.64, history of previous incarceration (AOR: 1.68; 95% CI: 1.43-1.98, history of mental illness (AOR 1.52; 95% CI: 1.31-1.78 and previous surgery (AOR 1.31; 95% CI: 1.12-1.52. Fifty-four (1.6% of all participants tested positive for HIV; this included 44 (1.54% men and 10 (1.92% women. Among male inmates, HIV infection was associated with homosexuality (AOR 6.20, 95% CI: 1.73-22.22, self-report of mental illness (AOR 2.18, 95% CI: 1.13-4.18, history of sexually transmitted infections (AOR 3.28, 95% CI: 1.64-6.56, and syphilis sero-positivity (AOR 2.54, 95% CI: 1.20-5.39. Among HIV-infected individuals, 34 (63% were unaware of their HIV status; only 23 of these 34 (68% newly diagnosed participants could be reached at six month follow-up, and 21 of 23 (91% were engaged in HIV care.HIV testing

  14. Integral tests of some high-threshold activation cross-sections of neutrons

    International Nuclear Information System (INIS)

    Vasil'eva, E.G.; Bukanov, V.N.; Kolotyj, V.V.; Pasechnik, V.M.; Trofimova, N.A.

    1993-01-01

    The coordination of differential data of excitation functions of activation reactions has been studied in the neutron energy ranges 3 - 55 MeV. Experiments have been performed in neutron fields got in reactions 9 Be(d,n) 10 B and 9 Be(p,n) 9 B at E d = 30, 40, 50 MeV and E p = 50 MeV. It is shown that differential data of reaction cross-sections 47 Ti(n,p) 47 Sc, nat. Ti(n,x) 47 Sc, 90 Zr(n,p) 90m Y, 93 Nb(n,a) 90m Y, 202 Tl(n,2 n) 203 Tl, 58 Ni(n,2 n) 57 Ni, 89 Y(n,2 n) 88 Y, 23 Na(n,2 n) 22 Na, 59 Co(n,3 n) 57 Co, 90 Zr(n,3 n) 88 Zr, 203 Tl(n,3 n) 201 Tl, 197 Au(n,4 n) 194 Au have not been determined for sure. These cross-sections demand further clarification. (author). 14 refs., 1 tab., 3 figs

  15. Thermodynamics of confined gallium clusters.

    Science.gov (United States)

    Chandrachud, Prachi

    2015-11-11

    We report the results of ab initio molecular dynamics simulations of Ga13 and Ga17 clusters confined inside carbon nanotubes with different diameters. The cluster-tube interaction is simulated by the Lennard-Jones (LJ) potential. We discuss the geometries, the nature of the bonding and the thermodynamics under confinement. The geometries as well as the isomer spectra of both the clusters are significantly affected. The degree of confinement decides the dimensionality of the clusters. We observe that a number of low-energy isomers appear under moderate confinement while some isomers seen in the free space disappear. Our finite-temperature simulations bring out interesting aspects, namely that the heat capacity curve is flat, even though the ground state is symmetric. Such a flat nature indicates that the phase change is continuous. This effect is due to the restricted phase space available to the system. These observations are supported by the mean square displacement of individual atoms, which are significantly smaller than in free space. The nature of the bonding is found to be approximately jellium-like. Finally we note the relevance of the work to the problem of single file diffusion for the case of the highest confinement.

  16. High Explosive Detonation–Confiner Interactions

    Science.gov (United States)

    Short, Mark; Quirk, James J.

    2018-01-01

    The primary purpose of a detonation in a high explosive (HE) is to provide the energy to drive a surrounding confiner, typically for mining or munitions applications. The details of the interaction between an HE detonation and its confinement are essential to achieving the objectives of the explosive device. For the high pressures induced by detonation loading, both the solid HE and confiner materials will flow. The structure and speed of a propagating detonation, and ultimately the pressures generated in the reaction zone to drive the confiner, depend on the induced flow both within the confiner and along the HE–confiner material interface. The detonation–confiner interactions are heavily influenced by the material properties and, in some cases, the thickness of the confiner. This review discusses the use of oblique shock polar analysis as a means of characterizing the possible range of detonation–confiner interactions. Computations that reveal the fluid mechanics of HE detonation–confiner interactions for finite reaction-zone length detonations are discussed and compared with the polar analysis. This includes cases of supersonic confiner flow; subsonic, shock-driven confiner flow; subsonic, but shockless confiner flow; and sonic flow at the intersection of the detonation shock and confiner material interface. We also summarize recent developments, including the effects of geometry and porous material confinement, on detonation–confiner interactions.

  17. CATTLE PRODUCTIVE PERFORMANCE EVALUATION CONFINED SUBMITTED IMMUNOCASTRATION

    Directory of Open Access Journals (Sweden)

    J. M. Maluf

    2016-09-01

    Full Text Available In order to evaluate the performance and carcass characteristics of cattle cross breeds ½ Aberdeen Angus x ½Nelore and Nelore confined submitted to immunocastration 218 male animals were used, feedlot, averaging 342 kg, divided into three experimental groups, T1: 117 steers ½ Angus x ½ Nelore no castrated (ANC, T2: 51 Nelore steers uncastrated (NNC and T3: 50 Nellore steers immunocastrated (NIC. The experiment lasted 144 days of confinement. The selection of animals for group formation was according to the individual weight, breed, sex condition and age. For immunocastration it wasused Bopriva® vaccine. The rating was finished according to the parameter used by the meatpacking industry ranging from 1 to 5. The experimental design was completely randomized in three groups. For the analyzes the variables studied statistics were submitted to analysis of variance (ANOVA and Tukey test both at the 5% level of significance. The results showed differences (p <0.01 at various features of productive performance and carcass between treatments. For slaughter weight, the ANC animals were higher (with 582.1 kg to Nelore, regardless of sexual condition, and the NNC were in turn heavier than the NIC, 527.4 and 503.7 respectively. Finally, it observed that the use of immunocastration in Nellore animals provided a decrease in productive performance of confined animals, but provided better finish carcass similar to crossbred (ANC.

  18. Constant speed control for complex cross-section welding using robot based on angle self-test

    Science.gov (United States)

    Xue, Long; Zou, Yong; Huang, Jiqiang; Huang, Junfen; Tao, Xinghua; Hu, Yanfeng

    2014-03-01

    Expandable profile liner(EPL) is a promising new oil well casing cementing technique, and welding is a major EPLs connection technology. Connection of EPL is still in the stage of manual welding so far, automatic welding technology is a hotspot of EPL which is one of the key technologies to be solved. A robot for automatic welding of "8" type EPL is studied. Four quadrants of mathematical equations of the 8-shaped cross-section track of EPL, consisting of multiple arcs, are established. Mechanism program for complex cross-section welding of EPL based on angle detection is proposed according to characteristics of small size, small valleys, and large forming errors, etc. A welding velocity vector control model is established by linkage control of a welding vehicle, a small driven actuator, and a height tracking mechanism. A constant speed control model based on an angle and symmetrical analysis model of rectangular coordinate system for EPL is built. Constraint conditions of constant speed control between each section are analyzed with 4 sections in first quadrant as an example, and cooperation work mechanism of the welding vehicle and the small tracking actuator is established based on pressure detection. The constant speed control model using angle self-test can be used to avoid the need for a precise mathematical model for tracking control and to adapt manufacture and installation deviation of EPL workpiece. The model is able to solve constant speed and trajectory tracking problems of EPL cross-section welding. EPL seams welded by the studied robot are good in appearance, and non-destructive testing(NDT) shows the seams are good in quality with no welding defects. Bulge tests show that the maximum pressure of welded EPL is 35 MPa, which can fulfill expansion performance requirements.

  19. To test or not to test: a cross-sectional survey of the psychosocial determinants of self-testing for cholesterol, glucose, and HIV.

    NARCIS (Netherlands)

    Grispen, J.E.; Ronda, G.; Dinant, G.J.; Vries, N.K. de; Weijden, G.D.E.M. van der

    2011-01-01

    BACKGROUND: Although self-tests are increasingly available and widely used, it is not clear whether their use is beneficial to the users, and little is known concerning the determinants of self-test use. The aim of this study was to identify the determinants of self-test use for cholesterol,

  20. What do Key Stakeholders Think About HIV Self-Testing in Canada? Results from a Cross-Sectional Survey.

    Science.gov (United States)

    Pai, N Pant; Smallwood, M; Gulati, D; Lapczak, N; Musten, A; Gaydos, C; Johnston, C; Steben, M; Wong, T; Engel, N; Kim, J

    2018-02-01

    Human immunodeficiency virus (HIV) self-testing presents an empowering alternative to facility-based testing for reaching undiagnosed HIV infected individuals, but is not currently available in Canada. We surveyed stakeholders (clinical providers, public health professionals, researchers) engaged in HIV testing initiatives nationwide to identify the concerns, opportunities and challenges to implementing HIV self-testing in Canada. An online cross-sectional survey was disseminated by the Canadian Institutes of Health Research Centre for REACH 2.0 National HIV & sexually transmitted and blood borne infections working group to stakeholders nationwide, with a target sample size of 200. Quantitative and qualitative data were analyzed using a mixed-methods, respondent-informed approach, to inform subsequent HIV self-testing in a country where self-testing is not yet accessible. A total of 183 responses were received. A majority (70.7%) (128/181) felt that self-testing was a necessary investment to reach the undiagnosed. 64.6% (117/181) felt that self-tests should be made available to their clients and 71.5% (128/179) of respondents agreed that self-test instructions required improvements. However, 50% (90/180) felt that self-testing will pose an economic challenge to current HIV testing models. Regardless, 21% urged for timely action and availability of HIV self-tests. Thematic analyses reflected the following concerns: (a) need for affordable self-tests, (b) need for expedited, customized, and accessible linkages to counselling, (c) concern for patients to cope with positive self-test results, (d) accuracy of self-tests to detect acute HIV and (e) liability in the context of non-disclosure. Stakeholders agreed to the provision of an option of HIV self-testing to reach the undiagnosed individuals. Concerns regarding costs and accuracy of self-tests, expedited linkages to counselling, and integration of self-test within prevailing HIV testing models, will need to be

  1. Correlations In Confined Quantum Plasmas

    International Nuclear Information System (INIS)

    Dufty, J.W.

    2012-01-01

    This is the final report for the project 'Correlations in Confined Quantum Plasmas', NSF-DOE Partnership Grant DE FG02 07ER54946, 8/1/2007 - 7/30/2010. The research was performed in collaboration with a group at Christian Albrechts University (CAU), Kiel, Germany. That collaboration, almost 15 years old, was formalized during the past four years under this NSF-DOE Partnership Grant to support graduate students at the two institutions and to facilitate frequent exchange visits. The research was focused on exploring the frontiers of charged particle physics evolving from new experimental access to unusual states associated with confinement. Particular attention was paid to combined effects of quantum mechanics and confinement. A suite of analytical and numerical tools tailored to the specific inquiry has been developed and employed

  2. Desire for predictive testing for Alzheimer's disease and impact on advance care planning: a cross-sectional study.

    Science.gov (United States)

    Sheffrin, Meera; Stijacic Cenzer, Irena; Steinman, Michael A

    2016-12-13

    It is unknown whether older adults in the United States would be willing to take a test predictive of future Alzheimer's disease, or whether testing would change behavior. Using a nationally representative sample, we explored who would take a free and definitive test predictive of Alzheimer's disease, and examined how using such a test may impact advance care planning. A cross-sectional study within the 2012 Health and Retirement Study of adults aged 65 years or older asked questions about a test predictive of Alzheimer's disease (N = 874). Subjects were asked whether they would want to take a hypothetical free and definitive test predictive of future Alzheimer's disease. Then, imagining they knew they would develop Alzheimer's disease, subjects rated the chance of completing advance care planning activities from 0 to 100. We classified a score > 50 as being likely to complete that activity. We evaluated characteristics associated with willingness to take a test for Alzheimer's disease, and how such a test would impact completing an advance directive and discussing health plans with loved ones. Overall, 75% (N = 648) of the sample would take a free and definitive test predictive of Alzheimer's disease. Older adults willing to take the test had similar race and educational levels to those who would not, but were more likely to be ≤75 years old (odds ratio 0.71 (95% CI 0.53-0.94)). Imagining they knew they would develop Alzheimer's, 81% would be likely to complete an advance directive, although only 15% had done so already. In this nationally representative sample, 75% of older adults would take a free and definitive test predictive of Alzheimer's disease. Many participants expressed intent to increase activities of advance care planning with this knowledge. This confirms high public interest in predictive testing for Alzheimer's disease and suggests this may be an opportunity to engage patients in advance care planning discussions.

  3. Hermitian relativity, chromodynamics and confinement

    International Nuclear Information System (INIS)

    Treder, H.J.

    1983-01-01

    The extension of the Riemann metrics of General Relativity to the complex domain (substitution of the symmetry conditions for the fundamental tensor, the affinity and the Ricci curvature by the conditions of hermicity) leads to a 'Generalized Theory of Gravity' (Einstein) describing the Newton-Einstein gravodynamics combined with the chromodynamics of quarks. The interaction of gravodynamics and chromodynamics implied by the Einstein-Schroedinger field equations of the hermitian relativity theory enforces the 'confinement'. The 'confinement' prevents the gravitational potential from divergence which would result in the lack of a Riemann space-time metric

  4. Hermitian relativity, chromodynamics and confinement

    Energy Technology Data Exchange (ETDEWEB)

    Treder, H.J. (Akademie der Wissenschaften der DDR, Potsdam-Babelsberg. Einstein-Laboratorium fuer Theoretische Physik)

    1983-01-01

    The extension of the Riemann metrics of General Relativity to the complex domain (substitution of the symmetry conditions for the fundamental tensor, the affinity and the Ricci curvature by the conditions of hermicity) leads to a 'Generalized Theory of Gravity' (Einstein) describing the Newton-Einstein gravodynamics combined with the chromodynamics of quarks. The interaction of gravodynamics and chromodynamics implied by the Einstein-Schroedinger field equations of the hermitian relativity theory enforces the 'confinement'. The 'confinement' prevents the gravitational potential from divergence which would result in the lack of a Riemann space-time metric.

  5. Some aspects of geometrical confinement

    Energy Technology Data Exchange (ETDEWEB)

    Novello, M.; De Lorenci, V.A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Elbaz, E. [Lyon-1 Univ., 69 - Villeurbanne (France)

    1998-04-01

    In this paper we present a toy model for the dynamics of a gauge field theory in such way that spin-one particles can be confined in a compact domain. We show that the property of confinement can be associated to the formation of a null surface identified to a horizon. This is due to the presence of an effective geometry generated by the self-interaction of the gauge field that guides the wave propagation of the field. This phenomenon has a striking analogy to the gravitational black hole in Einstein general theory of relativity, separating two domains of spacetime that can be trespassed only into one direction. (author) 4 refs.

  6. Test Data on Intumescent Fire Protection for Structural Steel Sections in Thailand

    Directory of Open Access Journals (Sweden)

    Thanyawat Pothisiri

    2012-04-01

    Full Text Available Current fire safety regulations in Thailand require that primary structural steel components of buildings be protected to achieve a minimum of 3-hour fire-resistance rating. For steel roof structures, 1-hour or 2-hour fire-resistance ratings may be specified depending on the number of stories. The verification methods of fire-resistance ratings set forth in the regulations are ISO 834 and ASTM E119 standards. The current trend of fire protection system for steel structures is intumescent paint due to aesthetical reasons. However, the fire-resistance ratings attained by proprietary intumescent systems currently available in the market are inconclusive. It is therefore the aim of this paper to provide an insight of the fire-resistance ratings of different intumescent products based on the data collected from the fire tests conducted by the Fire Safety Research Center of Chulalongkorn University during the period of 2009 - 2011. A statistical analysis was also conducted to compare the test data with the fire-resistance ratings specified in the current fire safety regulations.

  7. Immune responses in humans after 60 days of confinement

    Science.gov (United States)

    Schmitt, D. A.; Peres, C.; Sonnenfeld, G.; Tkackzuk, J.; Arquier, M.; Mauco, G.; Ohayon, E.

    1995-01-01

    A confinement experiment in a normobaric diving chamber was undertaken to better understand the effect of confinement and isolation on human psychology and physiology. Pre- and postconfinement blood samples were obtained from four test subjects and control donors to analyze immune responses. No modification in the levels of CD2+, CD3+, CD4+, CD8+, CD19+, and CD56+ cells was observed after confinement. Mitogen-induced T-lymphocyte proliferation and interleukin-2 receptor expression were not altered significantly. Whole blood interferon-alpha and gamma-induction and plasma cortisol levels were also unchanged, as was natural killer cell activity. These data suggest that in humans, no specific components of the immune response are affected by a 2-month isolation and confinement of a small group.

  8. Experimental tests of planar strain theory for predicting bone cross-sectional longitudinal and shear strains.

    Science.gov (United States)

    Verner, Kari A; Lehner, Michael; Lamas, Luis P; Main, Russell P

    2016-10-01

    Understanding of the diversity of skeletal loading regimes in vertebrate long bones during locomotion has been significantly enhanced by the application of planar strain theory (PST) to in vivo bone strain data. PST is used to model the distribution of longitudinal strains normal to the bone's transverse cross-section and the location of the neutral axis of bending. To our knowledge, the application of this theory to skeletal biomechanics has not been experimentally validated. We evaluated the accuracy of PST using strain measurements from emu tibiotarsi instrumented with four strain gauges and loaded in ex vivo four-point bending. Using measured strains from three-gauge combinations, PST was applied to predict strain values at a fourth gauge's location. Experimentally measured and predicted strain values correlated linearly with a slope near 1.0, suggesting that PST accurately predicts longitudinal strains. Additionally, we assessed the use of PST to extrapolate shear strains to locations on a bone not instrumented with rosette strain gauges. Guineafowl tibiotarsi were instrumented with rosette strain gauges and in vivo longitudinal and shear strains were measured during treadmill running. Individual-specific and sample-mean ratios between measured longitudinal strains from the medial and posterior bone surfaces were used to extrapolate posterior-site shear strain from shear strains measured on the medial surface. Measured and predicted shear strains at the posterior gauge site using either ratio showed trends for a positive correlation between measured and predicted strains, but the correlation did not equal 1.0 and had a non-zero intercept, suggesting that the use of PST should be carefully considered in the context of the goals of the study and the desired precision for the predicted shear strains. © 2016. Published by The Company of Biologists Ltd.

  9. Geomaterial characterizations of full scale pavement test sections for mechanistic analysis and design

    CSIR Research Space (South Africa)

    Kwon, J

    2007-02-01

    Full Text Available rate (inches/blow) of DCP. Accordingly, the DCP based evaluation of the test strip soil CBR values ranged from 5 to 28% before the top subgrade soils were prepared for pavement construction. Moisture Content, % 6 8 10 12 14 16 18 20 D ry D... en sit y, kN /m 3 15.7 16.5 17.3 18.1 18.8 19.6 20.4 C BR , % 0 5 10 15 20 25 30 Moisture-Density CBR Maximum Dry Density = 19.3 kN/m3 Optimum Moisture Content = 11.2 % CBR = 4 Dry Density = 18.9 kN/m3 Moisture Content...

  10. Wind Tunnel Testing of the NASA-DFRC Flutterometer using a Two DOF Wing Section

    Science.gov (United States)

    Strganac, Thomas W.

    2001-01-01

    Flutter of an aeroelastic structure is potentially destructive aeroelastic instability. This phenomenon has motivated research within the aeroelastic community to develop methods that can accurately predict aeroelastic instabilities. The Flutterometer method used herein, and as developed by NASA DFRC, is based upon the mu method which has been coupled with wavelet filtering processes in estimating aeroelastic models from flight data. The approach leads to a methodology to predict the occurrence of flutter boundaries, and may prove to reliably predict flutter boundaries during flight tests. An analytical model is used as the first estimate of the aeroelastic structural dynamics, and uncertainty operators are introduced into the system to model variations between the theoretical system and the physical system. The modelling uncertainties are then updated from experimental data. Although the model used did not work well with this particular experiment, a sensitivity analysis was additionally performed and improvements suggested.

  11. Hydraulic impact end effector final test report. Automation and robotics section, ER/WM-AT Program

    Energy Technology Data Exchange (ETDEWEB)

    Couture, S.

    1994-02-18

    One tool being developed for dislodging and fragmenting the hard salt cake waste in the single-shell nuclear waste tanks at the Hanford Reservation near Richland, Washington, is the hydraulic impact end effector (HIEE). This total operates by discharging 11-in. slugs of water at ultrahigh pressures. The HIEE was designed, built, and initially tested in 1992. Work in 1993 included advanced developments of the HIEE to further investigate its fragmentation abilities and to determine more effective operating procedures. These tests showed that more fragmentation can be achieved by increasing the charge pressure of 40 kpsi to 55 kpsi and by the use of different operating procedures. The size of the material and the impact energy of the water slug fired from the HIEE are believed to be major factors in material fragmentation. The material`s ability to fracture also appears to depend on the distance a fracture or crack line must travel to a free surface. Thus, larger material is more difficult to fracture than smaller material. Discharge pressures of 40 kpsi resulted in little penetration or fracturing of the material. At 55 kpsi, however, the size and depth of the fractures increased. Nozzle geometry had a significant effect on fragment size and quantity. Fragmentation was about an order of magnitude greater when the HIEE was discharged into drilled holes rather than onto the material surface. Since surface shots tend to create craters, a multi-shot procedure, coupled with an advanced nozzle design, was used to drill (crater) deep holes into large material. With this procedure, a 600-lb block was reduced to smaller pieces without the use of any additional equipment. Through this advanced development program, the HIEE has demonstrated that it can quickly fragment salt cake material into small, easily removable fragments. The HIEE`s material fragmentation ability can be substantially increased through the use of different nozzle geometries and operating procedures.

  12. Hydraulic impact end effector final test report. Automation and robotics section, ER/WM-AT Program

    International Nuclear Information System (INIS)

    Couture, S.

    1994-01-01

    One tool being developed for dislodging and fragmenting the hard salt cake waste in the single-shell nuclear waste tanks at the Hanford Reservation near Richland, Washington, is the hydraulic impact end effector (HIEE). This total operates by discharging 11-in. slugs of water at ultrahigh pressures. The HIEE was designed, built, and initially tested in 1992. Work in 1993 included advanced developments of the HIEE to further investigate its fragmentation abilities and to determine more effective operating procedures. These tests showed that more fragmentation can be achieved by increasing the charge pressure of 40 kpsi to 55 kpsi and by the use of different operating procedures. The size of the material and the impact energy of the water slug fired from the HIEE are believed to be major factors in material fragmentation. The material's ability to fracture also appears to depend on the distance a fracture or crack line must travel to a free surface. Thus, larger material is more difficult to fracture than smaller material. Discharge pressures of 40 kpsi resulted in little penetration or fracturing of the material. At 55 kpsi, however, the size and depth of the fractures increased. Nozzle geometry had a significant effect on fragment size and quantity. Fragmentation was about an order of magnitude greater when the HIEE was discharged into drilled holes rather than onto the material surface. Since surface shots tend to create craters, a multi-shot procedure, coupled with an advanced nozzle design, was used to drill (crater) deep holes into large material. With this procedure, a 600-lb block was reduced to smaller pieces without the use of any additional equipment. Through this advanced development program, the HIEE has demonstrated that it can quickly fragment salt cake material into small, easily removable fragments. The HIEE's material fragmentation ability can be substantially increased through the use of different nozzle geometries and operating procedures

  13. Tumor-infiltrating CD8+ lymphocytes predict different clinical outcomes in organ- and non-organ-confined urothelial carcinoma of the bladder following radical cystectomy.

    Science.gov (United States)

    Zhang, Shiqiang; Wang, Jun; Zhang, Xinyu; Zhou, Fangjian

    2017-01-01

    Tumor-infiltrating lymphocytes (TILs) are associated with better clinical outcomes in many tumors. TILs represent a cell-mediated immune response against the carcinoma. CD8+ TILs are a crucial component of cell-mediated immunity. The significance of CD8+ TILs has not been reported respectively in organ- and non-organ-confined urothelial carcinoma (UC) of the bladder. We explored the prognostic value of CD8+ TILs in the two groups. The presence of CD8+ TILs was assessed by immunohistochemical staining of whole tissue sections from 75 organ and 51 non-organ-confined disease patients with long-term follow-up, and its correlation with clinicopathological features and overall survival (OS) was determined. The CD8+ TIL immunohistochemical staining score was 0 (CD8 negative if the score was 0. There were no associations between CD8+ TILs and age, sex, nuclear grade, and adjuvant or neoadjuvant chemotherapy in organ- and non-organ-confined disease. The presence of CD8+ TILs was seen more frequently in pTa- 1 than pT 2 stage ( p  = 0.033) in organ-confined disease. No associations between CD8+ TILs and pT stage, pN stage were found in non-organ-confined disease. CD8+ TILs were associated with better OS (log-rank test, P  = 0.036) in non-organ-confined disease, but with poorer OS (log-rank test, P  = 0.040) in organ-confined disease by the Kaplan-Meier method. In multivariate analysis, CD8+ TILs were an independent favorable prognostic factor in non-organ-confined disease, but were an independent unfavorable prognostic factor in organ-confined disease. These results suggest that CD8+ TILs have clinically significant anti-tumor activity in non-organ-confined disease, but may have pro-tumor activity in organ-confined disease. Therefore, we should be cautious if CD8+ TILs are aimed to be exploited in the treatment of bladder cancer.

  14. Modeling Molecular Systems at Extreme Pressure by an Extension of the Polarizable Continuum Model (PCM) Based on the Symmetry-Adapted Cluster-Configuration Interaction (SAC-CI) Method: Confined Electronic Excited States of Furan as a Test Case.

    Science.gov (United States)

    Fukuda, Ryoichi; Ehara, Masahiro; Cammi, Roberto

    2015-05-12

    Novel molecular photochemistry can be developed by combining high pressure and laser irradiation. For studying such high-pressure effects on the confined electronic ground and excited states, we extend the PCM (polarizable continuum model) SAC (symmetry-adapted cluster) and SAC-CI (SAC-configuration interaction) methods to the PCM-XP (extreme pressure) framework. By using the PCM-XP SAC/SAC-CI method, molecular systems in various electronic states can be confined by polarizable media in a smooth and flexible way. The PCM-XP SAC/SAC-CI method is applied to a furan (C4H4O) molecule in cyclohexane at high pressure (1-60 GPa). The relationship between the calculated free-energy and cavity volume can be approximately represented with the Murnaghan equation of state. The excitation energies of furan in cyclohexane show blueshifts with increasing pressure, and the extents of the blueshifts significantly depend on the character of the excitations. Particularly large confinement effects are found in the Rydberg states. The energy ordering of the lowest Rydberg and valence states alters under high-pressure. The pressure effects on the electronic structure may be classified into two contributions: a confinement of the molecular orbital and a suppression of the mixing between the valence and Rydberg configurations. The valence or Rydberg character in an excited state is, therefore, enhanced under high pressure.

  15. Psychosocial determinants of HIV testing across stages of change in Spanish population: a cross-sectional national survey

    Directory of Open Access Journals (Sweden)

    Maria Jose Fuster-RuizdeApodaca

    2017-03-01

    Full Text Available Abstract Background The goal of this research is to study the psychosocial determinants of HIV-testing as a function of the decision or change stage concerning this health behavior. The determinants considered in the major ongoing health models and the stages contemplated in the Precaution Adoption Process Model are analysed. Methods A cross-sectional survey was administered to 1,554 people over 16 years of age living in Spain by a computer-assisted telephone interview (CATI. The sample design was randomised, with quotas of sex and age. The survey measured various psychosocial determinants of health behaviors considered in the main cognitive theories, the interviewees' stage of change concerning HIV-testing (lack of awareness, decision not to act, decision to act, action, maintenance, and abandonment, and the signal for the action of getting tested or the perceived barriers to being tested. Results Approximately two thirds of the population had not ever had the HIV test. The predominant stage was lack of awareness. The most frequently perceived barriers to testing were related to the health system and to the stigma. We also found that the psychosocial determinants studied differed depending on the respondents' stage of change. Perception of risk, perceived self-efficacy, proximity to people who had been tested, perceived benefits of knowing the diagnosis, and a positive instrumental and emotional attitude were positively associated with the decision and maintenance of testing behavior. However, unrealistic underestimation of the risk of HIV infection, stereotypes about the infection, and the perceived severity of HIV were associated with the decision not to be tested. Conclusions There are various sociocognitive and motivational profiles depending on people’s decision stage concerning HIV-testing. Knowing this profile may allow us to design interventions to influence the psychosocial determinants that characterise each stage of change.

  16. Effective viscosity of confined hydrocarbons

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, V.N.; Persson, B.N.J.

    2012-01-01

    We present molecular dynamics friction calculations for confined hydrocarbon films with molecular lengths from 20 to 1400 carbon atoms. We find that the logarithm of the effective viscosity ηeff for nanometer-thin films depends linearly on the logarithm of the shear rate: log ηeff=C-nlog γ̇, where...

  17. Confining membranes and dimensional reduction

    Science.gov (United States)

    Antonov, Dmitri

    2001-11-01

    The dual theory describing the 4D Coulomb gas of point-like magnetically charged objects, which confines closed electric strings, is considered. The respective generalization of the theory of confining strings to confining membranes is further constructed. The same is done for the analogous SU(3)-inspired model. We then consider a combined model which confines both electric charges and closed strings. Such a model is a mixture of the above-mentioned Coulomb gas with the condensate of the dual Higgs field, where the latter one is described by the dual abelian Higgs model. It is demonstrated that in a certain limit of this dual abelian Higgs model, the system under study undergoes naively the dimensional reduction and becomes described by the (completely integrable) 2D sine-Gordon theory. In particular, at finite temperature, this fact leads to the phase transition of the Berezinskii-Kosterlitz-Thouless type with the respective critical temperature expressed in terms of the parameters of the dual abelian Higgs model. However, it is finally discussed that the dimensional reduction is rigorously valid only in the strong coupling limit of the original 4D Coulomb gas. In such a limit, this reduction transforms the combined model into the 2D free bosonic theory.

  18. Turbulent jet in confined counterflow

    Indian Academy of Sciences (India)

    Abstract. The mean flowfield of a turbulent jet issuing into a confined, uniform counterflow was investigated computationally. Based on dimensional analysis, the jet penetration length was shown to scale with jet-to-counterflow momentum flux ratio. This scaling and the computational results reproduce the well-known correct ...

  19. Is confinement the ultimate truth

    International Nuclear Information System (INIS)

    Thirrring, W.

    1980-01-01

    This seminar discusses a field theory which leads to a r-potential and therefore to a confinement. By comparison to the instability due to a resonance phenomenon, the author concentrates on the theory's ghost problem and concludes that for some couplings this does not occur and the theory behaves reasonably

  20. Turbulent jet in confined counterflow

    Indian Academy of Sciences (India)

    The mean flowfield of a turbulent jet issuing into a confined, uniform counterflow was investigated computationally. Based on dimensional analysis, the jet penetration length was shown to scale with jet-to-counterflow momentum flux ratio. This scaling and the computational results reproduce the well-known correct limit of ...

  1. Effects of coffee, smoking, and alcohol on liver function tests: a comprehensive cross-sectional study.

    Science.gov (United States)

    Jang, Eun Sun; Jeong, Sook-Hyang; Hwang, Sung Ho; Kim, Hyun Young; Ahn, So Yeon; Lee, Jaebong; Lee, Sang Hyub; Park, Young Soo; Hwang, Jin Hyeok; Kim, Jin-Wook; Kim, Nayoung; Lee, Dong Ho

    2012-10-18

    Liver function tests (LFTs) can be affected by many factors and the proposed effects of coffee on LFT require a comprehensive evaluation. The aim of this study was to elucidate whether drinking coffee, smoking, or drinking alcohol have independent effects on LFTs in Korean health-check examinees. We used the responses of 500 health-check examinees, who had participated in a self-administered questionnaire survey about coffee, alcohol drinking, and smoking habits. Coffee consumption was closely related to male gender, high body mass index (BMI), alcohol drinking, and smoking. On univariable and multivariable analyses, drinking coffee lowered serum levels of total protein, albumin, and aspartate aminotransferases (AST). On multivariable analyses, smoking raised serum γ-glutamyl transferase (GGT) level and decreased serum protein and albumin levels, while alcohol drinking raised GGT level after adjustment for age, gender, regular medication, BMI, coffee and alcohol drinking amounts, and smoking. Coffee consumption, smoking, and alcohol drinking affect the individual components of LFT in different ways, and the above 3 habits each have an impact on LFTs. Therefore, their effects on LFTs should be carefully interpreted, and further study on the mechanism of the effects is warranted.

  2. Effects of coffee, smoking, and alcohol on liver function tests: a comprehensive cross-sectional study

    Directory of Open Access Journals (Sweden)

    Jang Eun

    2012-10-01

    Full Text Available Abstract Background Liver function tests (LFTs can be affected by many factors and the proposed effects of coffee on LFT require a comprehensive evaluation. The aim of this study was to elucidate whether drinking coffee, smoking, or drinking alcohol have independent effects on LFTs in Korean health-check examinees. Methods We used the responses of 500 health-check examinees, who had participated in a self-administered questionnaire survey about coffee, alcohol drinking, and smoking habits. Results Coffee consumption was closely related to male gender, high body mass index (BMI, alcohol drinking, and smoking. On univariable and multivariable analyses, drinking coffee lowered serum levels of total protein, albumin, and aspartate aminotransferases (AST. On multivariable analyses, smoking raised serum γ-glutamyl transferase (GGT level and decreased serum protein and albumin levels, while alcohol drinking raised GGT level after adjustment for age, gender, regular medication, BMI, coffee and alcohol drinking amounts, and smoking. Conclusions Coffee consumption, smoking, and alcohol drinking affect the individual components of LFT in different ways, and the above 3 habits each have an impact on LFTs. Therefore, their effects on LFTs should be carefully interpreted, and further study on the mechanism of the effects is warranted.

  3. Reverberation cancellation in a closed test section of a wind tunnel using a multi-microphone cesptral method

    Science.gov (United States)

    Blacodon, D.; Bulté, J.

    2014-04-01

    Nowadays, although aerodynamic data are still primarily sought after during wind tunnel tests, reliable acoustic measurements also become a priority for aircraft designers. In order to gather both kinds of data, aerodynamic and acoustic tests are carried out simultaneously under the same closed test section. This solution has two major drawbacks: the acoustic signals delivered by microphones may be corrupted by the boundary layer expanding on the wind tunnel walls and by the reverberant noise originating from reflective surfaces. Technological solutions can be deployed to reduce the corruption of the signals by the wind tunnel background noise. Methods based on the power cepstrum can be used to reduce reverberation effects by removing the quefrencies due to the echoes in the cepstral domain.

  4. 8 CFR 236.2 - Confined aliens, incompetents, and minors.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Confined aliens, incompetents, and minors. 236.2 Section 236.2 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED Detention...

  5. 8 CFR 1236.2 - Confined aliens, incompetents, and minors.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Confined aliens, incompetents, and minors. 1236.2 Section 1236.2 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL...

  6. Prevalence of prior HIV testing and associated factors among MSM in Zhejiang Province, China: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Runhua Li

    2016-11-01

    Full Text Available Abstract Background Men who have sex with men (MSM have become one of high-risk population for human immunodeficiency virus (HIV infection, due to their multiple sex partners and unprotected anal intercourse. Promoting HIV testing is an effective strategy for the prevention and control of HIV infection. We assessed the factors associated with a prior HIV testing history, which could provide guidance for implementation of future HIV intervention programs. Methods A cross-sectional study was conducted in three cities of Zhejiang Province, namely, Hangzhou, Ningbo and Wenzhou, using respondent-driven sampling, between December 2013 and June 2014. A face-to-face questionnaire survey was employed to collect relevant information about HIV testing. Univariate and multivariate logistic regression analyses were used to identify the factors associated with a prior HIV testing history. Results The adjusted rate of prior HIV testing among MSM in Zhejiang Province was 55.9 %. The adjusted rates of HIV and syphilis infections among MSM in Zhejiang Province were 14.0 % and 11.4 %, respectively. A weighted multivariate analysis showed that MSM of older age were more likely to be tested, as were MSM with higher level of education, self-reported homosexuality and a higher frequency of receiving AIDS/sexually transmitted infections educational intervention in the past year. MSM with suicidal inclination and self-perceived lower possibility of HIV infection were less likely to report ever having undergone an HIV test. Conclusions The prevalence of prior HIV testing among MSM in Zhejiang Province, China is low. Effective and more frequent interventional measures should be adopted to improve risk awareness and psychosocial support for younger, less educated MSM, and to encourage more MSM to undergo HIV testing.

  7. Mechanical behavior of confined self-compacting reinforced concrete circular columns under concentric axial loading

    Directory of Open Access Journals (Sweden)

    Fouad Khairallah

    2013-12-01

    Full Text Available While there is abundant research information on ordinary confined concrete, there are little data on the behavior of Self-Compacting Concrete (SCC under such condition. Due to higher shrinkage and lower coarse aggregate content of SCC compared to that of Normal Concrete (NC, its composite performance under confined conditions needs more investigation. This paper has been devoted to investigate and compare the mechanical behavior of confined concrete circular columns cast with SCC and NC under concentric axial loading. The parameters affecting are including concrete compressive strength and confinement configuration. Twenty column specimens were casted and confined using four confinement techniques, CFRP wrap, FRP tube, GFRP wrap, and spiral steel hoops. The performance of the tested column specimens is evaluated based on mode of failure, load–displacement curve, stress–strain characteristics, ultimate strength, ductility, and degree of confinement.

  8. Numerical analysis on inlet and outlet sections of a test fuel assembly for a Supercritical Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kiss, Attila, E-mail: kissa@reak.bme.hu; Vágó, Tamás; Aszódi, Attila

    2015-12-15

    Graphical abstract: - Highlights: • SCWR-FQT, first facility works with nuclear fuel cooled by SCW, was analysed. • The inlet and outlet section of the test fuel assembly was investigated by CFD. • Two thermohydraulic problems were revealed, described and analysed. • To solve them design changes were proposed and proven by further analysis. - Abstract: The Supercritical Water Reactor (SCWR) is one of the six reactor concepts being investigated under the framework of the Generation IV International Forum (GIF). One of the major challenges in the development of a SCWR is to develop materials for the fuel and core structures that will be sufficiently corrosion-resistant to withstand supercritical water conditions. Previously, core, reactor and plant design concept of the European High Performance Light Water Reactor (HPLWR) have been worked out in substantial detail. As the next step, it has been proposed to carry out a fuel qualification test of a small scale fuel assembly in a research reactor under typical prototype conditions. Therefore design and licensing of an experimental facility for the fuel qualification test, including the small scale fuel assembly with four fuel rods, the required coolant loop with supercritical water and safety and auxiliary systems, is the scope of the project “Supercritical Water Reactor—Fuel Qualification Test” (SCWR-FQT). This project is a collaborative project co-funded by the European Commission, which takes advantage of a Chinese—European collaboration. As a sub-task of the SCWR-FQT project, the geometry of inlet and outlet sections of the fuel assembly has to be investigated and optimized according to thermohydraulic considerations such as expected stable and uniform inflow pattern and uniform outflow temperature field conditions. To accomplish this task three dimensional CFD analysis has been performed. During the analysis two main problems were identified. On the one hand, generation of a huge eddy was

  9. Surface motion and confinement potential for a microwave confined corona

    International Nuclear Information System (INIS)

    Ensley, D.L.

    1979-07-01

    Approximate time dependent solutions for surface velocities and potentials are given for a plane polarized microwave field confining a hot, over-dense plasma corona. Steady state solutions to Poissons' equation can be applied to the time dependent case, provided transit time effects are included. The product of ion pressure and potential wave (surface) velocity gives an average heating rate approx. 7/32 NKT 0 V/sub theta/ directly to the ions

  10. Knowledge, attitudes and preferences regarding genetic testing for smoking cessation. A cross-sectional survey among Dutch smokers.

    Science.gov (United States)

    Quaak, Marieke; Smerecnik, Chris; van Schooten, Frederik J; de Vries, Hein; van Schayck, Constant P

    2012-01-01

    Objectives Recent research strongly suggests that genetic variation influences smokers' ability to stop. Therefore, the use of (pharmaco) genetic testing may increase cessation rates. This study aims to assess the intention of smokers concerning undergoing genetic testing for smoking cessation and their knowledge, attitudes and preferences about this subject. Design Online cross-sectional survey. Setting Database internet research company of which every inhabitant of the Netherlands of ≥12 years with an email address and capable of understanding Dutch can become a member. Participants 587 of 711 Dutch smokers aged ≥18 years, daily smokers for ≥5 years and smoke on average ≥10 cigarettes/day (response rate=83%). Primary and secondary outcome measures Smokers' knowledge, attitudes and preferences and their intention to undergo genetic testing for smoking cessation. Results Knowledge on the influence of genetic factors in smoking addiction and cessation was found to be low. Smokers underestimated their chances of having a genetic predisposition and the influence of this on smoking cessation. Participants perceived few disadvantages, some advantages and showed moderate self-efficacy towards undergoing a genetic test and dealing with the results. Smokers were mildly interested in receiving information and participating in genetic testing, especially when offered by their general practitioner (GP). Conclusions For successful implementation of genetic testing for smoking in general practice, several issues should be addressed, such as the knowledge on smoking cessation, genetics and genetic testing (including advantages and disadvantages) and the influence of genetics on smoking addiction and cessation. Furthermore, smokers allocate their GPs a crucial role in the provision of information and the delivery of a genetic test for smoking; however, it is unclear whether GPs will be able and willing to take on this role.

  11. Reduction of cross section area at fracture in tensile test: measurement and applications for flat sheet steels

    Science.gov (United States)

    Larour, P.; Freudenthaler, J.; Weissböck, T.

    2017-09-01

    This contribution deals with the use of maximum thinning and reduction of sample cross section area at fracture after tensile testing and applications for industrial flat sheet steels. Although included in all usual tensile testing standards, this mechanical property (“Z-value”) has long been neglected for flat sheet materials. It happens however to include some most valuable information on local ductility at fracture of sheet steels. This is increasingly needed for a more suitable description and ranking of newly developed advanced high strength sheet steels with regard to local ductility (stretch-flangeability, bendability, crash-ability) versus global ductility (deep-drawability). It is shown in this investigation that the ISO16630 punched and milled hole expansion ratio correlates linearly with the relative thickness reduction at fracture. A classification of cold rolled AHSS-UHSS sheet steels is attempted by plotting the relative thickness & area reduction at fracture vs. uniform and fracture elongation.

  12. Laterality judgments in people with low back pain--A cross-sectional observational and test-retest reliability study.

    Science.gov (United States)

    Linder, Martin; Michaelson, Peter; Röijezon, Ulrik

    2016-02-01

    Disruption of cortical representation, or body schema, has been indicated as a factor in the persistence and recurrence of low back pain (LBP). This has been observed through impaired laterality judgment ability and it has been suggested that this ability is affected in a spatial rather than anatomical manner. We compared laterality judgment performance of foot and trunk movements between people with LBP with or without leg pain and healthy controls, and investigated associations between test performance and pain. We also assessed the test-retest reliability of the Recognise Online™ software when used in a clinical and a home setting. Cross-sectional observational and test-retest study. Thirty individuals with LBP and 30 healthy controls performed judgment tests of foot and trunk laterality once supervised in a clinic and twice at home. No statistically significant group differences were found. LBP intensity was negatively related to trunk laterality accuracy (p = 0.019). Intraclass correlation values ranged from 0.51 to 0.91. Reaction time improved significantly between test occasions while accuracy did not. Laterality judgments were not impaired in subjects with LBP compared to controls. Further research may clarify the relationship between pain mechanisms in LBP and laterality judgment ability. Reliability values were mostly acceptable, with wide and low confidence intervals, suggesting test-retest reliability for Recognise Online™ could be questioned in this trial. A significant learning effect was observed which should be considered in clinical and research application of the test. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Parental Attitudes to Genetic Testing Differ by Ethnicity and Immigration in Childhood Nephrotic Syndrome: A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Karlota Borges

    2016-03-01

    Full Text Available Background: Studies in the USA report differences in opinion among parents of different ethnic groups toward genetic testing for their child; however, there are no studies that address this issue in the diverse ethnic and immigrant population in Canada. Objective: This study aims to determine whether ethnicity and immigration status influences parental interest in clinical genetic testing for a potentially progressive kidney disease. Design: This is a cross-sectional study. Setting: Participants were recruited from the Greater Toronto Area, Canada. Participants: The study included 320 parents of children ages 1–18 years with nephrotic syndrome enrolled in the Insight into Nephrotic Syndrome: Investigating Genes, Health and Therapeutics (INSIGHT observational cohort study. Measurements: Demographic, ethnicity, immigration, and child specific factors as well as interest in genetic testing were collected through self-reported questionnaires administered at baseline study visit. Methods: Logistic regression models were used to examine association of ethnicity and immigration status with interest in genetic testing. Results: The majority of parents (85 % were interested in genetic testing for their child. South Asian and East/Southeast Asian parents had 74 and 76 % lower odds of agreeing to genetic testing when compared to Europeans (odds ratio (OR 0.26, 95 % confidence interval (CI 0.10–0.68; OR 0.24, 95 % CI 0.07–0.79, respectively after controlling for age and sex of child, age and education level of parent, initial steroid resistance, and duration of time in Canada. Immigrants to Canada also had significantly lower odds (OR 0.29, 95 % CI 0.12–0.72 of agreeing to genetic testing after similar adjustment. Higher education level was not associated with greater interest in genetic testing (OR 1.24, 95 % CI 0.64–2.42. Limitations: Participants have already agreed to aggregate genetic testing for research purposes as part of enrolment in

  14. Parental attitudes to genetic testing differ by ethnicity and immigration in childhood nephrotic syndrome: a cross-sectional study.

    Science.gov (United States)

    Borges, Karlota; Vasilevska-Ristovska, Jovanka; Hussain-Shamsy, Neesha; Patel, Viral; Banh, Tonny; Hebert, Diane; Pearl, Rachel J; Radhakrishnan, Seetha; Piscione, Tino D; Licht, Christoph P B; Langlois, Valerie; Levin, Leo; Strug, Lisa; Parekh, Rulan S

    2016-01-01

    Studies in the USA report differences in opinion among parents of different ethnic groups toward genetic testing for their child; however, there are no studies that address this issue in the diverse ethnic and immigrant population in Canada. This study aims to determine whether ethnicity and immigration status influences parental interest in clinical genetic testing for a potentially progressive kidney disease. This is a cross-sectional study. Participants were recruited from the Greater Toronto Area, Canada. The study included 320 parents of children ages 1-18 years with nephrotic syndrome enrolled in the Insight into Nephrotic Syndrome: Investigating Genes, Health and Therapeutics (INSIGHT) observational cohort study. Demographic, ethnicity, immigration, and child specific factors as well as interest in genetic testing were collected through self-reported questionnaires administered at baseline study visit. Logistic regression models were used to examine association of ethnicity and immigration status with interest in genetic testing. The majority of parents (85 %) were interested in genetic testing for their child. South Asian and East/Southeast Asian parents had 74 and 76 % lower odds of agreeing to genetic testing when compared to Europeans (odds ratio (OR) 0.26, 95 % confidence interval (CI) 0.10-0.68; OR 0.24, 95 % CI 0.07-0.79, respectively) after controlling for age and sex of child, age and education level of parent, initial steroid resistance, and duration of time in Canada. Immigrants to Canada also had significantly lower odds (OR 0.29, 95 % CI 0.12-0.72) of agreeing to genetic testing after similar adjustment. Higher education level was not associated with greater interest in genetic testing (OR 1.24, 95 % CI 0.64-2.42). Participants have already agreed to aggregate genetic testing for research purposes as part of enrolment in INSIGHT study. While majority of parents were interested in genetic testing for their child, immigrants, particularly

  15. Community engagement in sexual health and uptake of HIV testing and syphilis testing among MSM in China: a cross-sectional online survey.

    Science.gov (United States)

    Zhang, Tiange P; Liu, Chuncheng; Han, Larry; Tang, Weiming; Mao, Jessica; Wong, Terrence; Zhang, Ye; Tang, Songyuan; Yang, Bin; Wei, Chongyi; Tucker, Joseph D

    2017-04-03

    HIV and syphilis testing rates remain low among men who have sex with men (MSM) in low- and middle-income countries (LMICs). Community engagement has been increasingly used to promote HIV testing among key populations in high-income countries, often in settings with stronger civil society. This study aimed to assess socio-demographic, behavioural, and community engagement factors associated with HIV and syphilis testing among MSM in China. MSM ≥16 years old who had condomless sex in the past three months were recruited nationwide to complete a cross-sectional online survey in November 2015. Data were collected on socio-demographics, sexual behaviours, HIV testing, syphilis testing, and community engagement in sexual health. We defined community engagement in sexual health using six items assessing awareness and advocacy of sexual health programmes. The underlying factor structure of a 6-item community engagement scale was determined through exploratory factor analysis. Univariate and multivariable logistic regressions identified correlates of HIV and syphilis testing. 1189 MSM were recruited. 54% (647/1189) of men had ever tested for HIV and 30% (354/1189) had ever tested for syphilis. Factor analysis suggested three levels of community engagement (minimal, moderate, and substantial) and this model explained 79.5% of observed variance. A quarter (26%, 312/1189) reported none to minimal engagement, over one half (54%, 644/1189) reported moderate engagement, and a fifth (20%, 233/1189) reported substantial engagement. Multivariable logistic regression showed that MSM with greater community engagement in sexual health were more likely to have ever tested for HIV (substantial vs. no engagement: aOR 7.91, 95% CI 4.98-12.57) and for syphilis (substantial vs. no engagement: aOR 5.35, 95% CI 3.16-9.04). HIV and syphilis testing are suboptimal among MSM in China. Community engagement may be useful for promoting testing in China and should be considered in intervention

  16. Testing a self-determination theory model of children's physical activity motivation: a cross-sectional study.

    Science.gov (United States)

    Sebire, Simon J; Jago, Russell; Fox, Kenneth R; Edwards, Mark J; Thompson, Janice L

    2013-09-26

    Understanding children's physical activity motivation, its antecedents and associations with behavior is important and can be advanced by using self-determination theory. However, research among youth is largely restricted to adolescents and studies of motivation within certain contexts (e.g., physical education). There are no measures of self-determination theory constructs (physical activity motivation or psychological need satisfaction) for use among children and no previous studies have tested a self-determination theory-based model of children's physical activity motivation. The purpose of this study was to test the reliability and validity of scores derived from scales adapted to measure self-determination theory constructs among children and test a motivational model predicting accelerometer-derived physical activity. Cross-sectional data from 462 children aged 7 to 11 years from 20 primary schools in Bristol, UK were analysed. Confirmatory factor analysis was used to examine the construct validity of adapted behavioral regulation and psychological need satisfaction scales. Structural equation modelling was used to test cross-sectional associations between psychological need satisfaction, motivation types and physical activity assessed by accelerometer. The construct validity and reliability of the motivation and psychological need satisfaction measures were supported. Structural equation modelling provided evidence for a motivational model in which psychological need satisfaction was positively associated with intrinsic and identified motivation types and intrinsic motivation was positively associated with children's minutes in moderate-to-vigorous physical activity. The study provides evidence for the psychometric properties of measures of motivation aligned with self-determination theory among children. Children's motivation that is based on enjoyment and inherent satisfaction of physical activity is associated with their objectively-assessed physical

  17. Testing a self-determination theory model of children’s physical activity motivation: a cross-sectional study

    Science.gov (United States)

    2013-01-01

    Background Understanding children’s physical activity motivation, its antecedents and associations with behavior is important and can be advanced by using self-determination theory. However, research among youth is largely restricted to adolescents and studies of motivation within certain contexts (e.g., physical education). There are no measures of self-determination theory constructs (physical activity motivation or psychological need satisfaction) for use among children and no previous studies have tested a self-determination theory-based model of children’s physical activity motivation. The purpose of this study was to test the reliability and validity of scores derived from scales adapted to measure self-determination theory constructs among children and test a motivational model predicting accelerometer-derived physical activity. Methods Cross-sectional data from 462 children aged 7 to 11 years from 20 primary schools in Bristol, UK were analysed. Confirmatory factor analysis was used to examine the construct validity of adapted behavioral regulation and psychological need satisfaction scales. Structural equation modelling was used to test cross-sectional associations between psychological need satisfaction, motivation types and physical activity assessed by accelerometer. Results The construct validity and reliability of the motivation and psychological need satisfaction measures were supported. Structural equation modelling provided evidence for a motivational model in which psychological need satisfaction was positively associated with intrinsic and identified motivation types and intrinsic motivation was positively associated with children’s minutes in moderate-to-vigorous physical activity. Conclusions The study provides evidence for the psychometric properties of measures of motivation aligned with self-determination theory among children. Children’s motivation that is based on enjoyment and inherent satisfaction of physical activity is

  18. Theory of rheology in confinement.

    Science.gov (United States)

    Aerov, Artem A; Krüger, Matthias

    2015-10-01

    The viscosity of fluids is generally understood in terms of kinetic mechanisms, i.e., particle collisions, or thermodynamic ones as imposed through structural distortions upon, e.g., applying shear. Often the latter are more relevant, which allows a simpler theoretical description, and, e.g., (damped) Brownian particles can be considered good fluid model systems. We formulate a general theoretical approach for rheology in confinement, based on microscopic equations of motion and classical density functional theory. Specifically, we discuss the viscosity for the case of two parallel walls in relative motion as a function of the wall-to-wall distance, analyzing its relation to the slip length found for a single wall. The previously observed [A. A. Aerov and M. Krüger, J. Chem. Phys. 140, 094701 (2014).] deficiency of inhomogeneous (unphysical) stresses under naive application of shear in confinement is healed when hydrodynamic interactions are included.

  19. Physics of magnetic confinement fusion

    Science.gov (United States)

    Wagner, F.

    2013-06-01

    Fusion is the energy source of the universe. The local conditions in the core of the Sun allow the transfer of mass into energy, which is finally released in the form of radiation. Technical fusion melts deuterons and tritons to helium releasing large amounts of energy per fusion process. Because of the conditions for fusion, which will be deduced, the fusion fuel is in the plasma state. Here we report on the confinement of fusion plasmas by magnetic fields. Different confinement concepts — tokamaks and stellarators — will be introduced and described. The first fusion reactor, ITER, and the most modern stellarator, Wendelstein 7-X, are under construction. Their basic features and objectives will be presented.

  20. Physics of magnetic confinement fusion

    Directory of Open Access Journals (Sweden)

    Wagner F.

    2013-06-01

    Full Text Available Fusion is the energy source of the universe. The local conditions in the core of the Sun allow the transfer of mass into energy, which is finally released in the form of radiation. Technical fusion melts deuterons and tritons to helium releasing large amounts of energy per fusion process. Because of the conditions for fusion, which will be deduced, the fusion fuel is in the plasma state. Here we report on the confinement of fusion plasmas by magnetic fields. Different confinement concepts — tokamaks and stellarators — will be introduced and described. The first fusion reactor, ITER, and the most modern stellarator, Wendelstein 7-X, are under construction. Their basic features and objectives will be presented.

  1. Inertial Electrostatic Confinement (IEC) devices

    International Nuclear Information System (INIS)

    Nebel, R.A.; Turner, L.; Tiouririne, T.N.; Barnes, D.C.; Nystrom, W.D.; Bussard, R.W.; Miley, G.H.; Javedani, J.; Yamamoto, Y.

    1994-01-01

    Inertial Electrostatic Confinement (IEC) is one of the earliest plasma confinement concepts, having first been suggested by P. T. Farnsworth in the 1950s. The concept involves a simple apparatus of concentric spherical electrostatic grids or a combination of grids and magnetic fields. An electrostatic structure is formed from the confluence of electron or ion beams. Gridded IEC systems have demonstrated neutron yields as high as 2 * 10 10 neutrons/sec. These systems have considerable potential as small, inexpensive, portable neutron sources for assaying applications. Neutron tomography is also a potential application. Atomic physics effects strongly influence the performance of all of these systems. Important atomic effects include elastic scattering, ionization, excitation, and charge exchange. This paper discusses how an IEC system is influenced by these effects and how to design around them. Theoretical modeling and experimental results are presented

  2. Confinement and diffusion in tokamaks

    International Nuclear Information System (INIS)

    McWilliams, R.

    1988-01-01

    The effect of electric field fluctuations on confinement and diffusion in tokamak is discussed. Based on the experimentally determined cross-field turbolent diffusion coefficient, D∼3.7*cT e /eB(δn i /n i ) rms which is also derived by a simple theory, the cross-field diffusion time, tp=a 2 /D, is calculated and compared to experimental results from 51 tokamak for standard Ohmic operation

  3. Holographic confinement in inhomogeneous backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Marolf, Donald; Wien, Jason [Department of Physics, University of California,Santa Barbara, CA 93106 (United States)

    2016-08-02

    As noted by Witten, compactifying a d-dimensional holographic CFT on an S{sup 1} gives a class of (d−1)-dimensional confining theories with gravity duals. The prototypical bulk solution dual to the ground state is a double Wick rotation of the AdS{sub d+1} Schwarzschild black hole known as the AdS soliton. We generalize such examples by allowing slow variations in the size of the S{sup 1}, and thus in the confinement scale. Coefficients governing the second order response of the system are computed for 3≤d≤8 using a derivative expansion closely related to the fluid-gravity correspondence. The primary physical results are that i) gauge-theory flux tubes tend to align orthogonal to gradients and along the eigenvector of the Hessian with the lowest eigenvalue, ii) flux tubes aligned orthogonal to gradients are attracted to gradients for d≤6 but repelled by gradients for d≥7, iii) flux tubes are repelled by regions where the second derivative along the tube is large and positive but are attracted to regions where the eigenvalues of the Hessian are large and positive in directions orthogonal to the tube, and iv) for d>3, inhomogeneities act to raise the total energy of the confining vacuum above its zeroth order value.

  4. Confinement-induced Molecular Templating and Controlled Ligation

    Science.gov (United States)

    Berard, Daniel; Shayegan, Marjan; Michaud, François; Henkin, Gil; Scott, Shane; Leith, Jason; Leslie, Sabrina; Leslie Lab Team

    Loading and manipulating long DNA molecules within sub-50 nm cross-section nanostructures for genomic and biochemical analyses, while retaining their structural integrity, present key technological challenges to the biotechnology sector, such as device clogging and molecular breakage. We overcome these challenges by using Convex Lens-induced Confinement (CLiC) technology to gently load DNA into nanogrooves from above. Here, we demonstrate single-fluorophore visualization of custom DNA barcodes as well as efficient top-loading of DNA into sub-50 nm nanogrooves of variable topographies. We study confinement-enhanced self-ligation of polymers loaded in circular nanogrooves. Further, we use concentric, circular nanogrooves to eliminate confinement gradient-induced drift of stretched DNA.

  5. On the buckling of elastic rings by external confinement.

    Science.gov (United States)

    Hazel, Andrew L; Mullin, Tom

    2017-05-13

    We report the results of an experimental and numerical investigation into the buckling of thin elastic rings confined within containers of circular or regular polygonal cross section. The rings float on the surface of water held in the container and controlled removal of the fluid increases the confinement of the ring. The increased compressive forces can cause the ring to buckle into a variety of shapes. For the circular container, finite perturbations are required to induce buckling, whereas in polygonal containers the buckling occurs through a linear instability that is closely related to the canonical Euler column buckling. A model based on Kirchhoff-Love beam theory is developed and solved numerically, showing good agreement with the experiments and revealing that in polygons increasing the number of sides means that buckling occurs at reduced levels of confinement.This article is part of the themed issue 'Patterning through instabilities in complex media: theory and applications.' © 2017 The Author(s).

  6. A cross-sectional study of the association between mobility test performance and personality among older adults.

    Science.gov (United States)

    Agmon, Maayan; Armon, Galit

    2016-05-18

    Falls among the elderly are a major public health challenge. The Timed-Up and Go (TUG) test is commonly used to identify older adults with mobility limitations. This study explored the association between TUG test results and personality among community-dwelling older adults. This cross-sectional study included 85 older adults. Personality was evaluated with the Five Factor Model. Times to complete the TUG as a single task (TUGST) alone and also with an additional cognitive task i.e., dual-task (DT), were recorded. Ordinary least squares OLS regression models were used to examine the associations between personality factors and both single DT TUG. Extraversion was found to be inversely associated with time to complete the TUGST (β = -.26, p older adults with high Extraversion completed the TUGST test more quickly than those who had lower measures of this trait and, people with high Conscientiousness completed the TUGDT tests more quickly. These findings may contribute to early identification of older adults at higher risk from mobility limitations and falls, and to developing personality-tailored interventions for fall prevention.

  7. Work-related stress is associated with impaired neuropsychological test performance: a clinical cross-sectional study.

    Science.gov (United States)

    Eskildsen, Anita; Andersen, Lars Peter; Pedersen, Anders Degn; Vandborg, Sanne Kjær; Andersen, Johan Hviid

    2015-01-01

    Patients on sick leave due to work-related stress often complain about impaired concentration and memory. However, it is undetermined how widespread these impairments are, and which cognitive domains are most long-term stress sensitive. Previous studies show inconsistent results and are difficult to synthesize. The primary aim of this study was to examine whether patients with work-related stress complaints have cognitive impairments compared to a matched control group without stress. Our secondary aim was to examine whether the level of self-reported perceived stress is associated with neuropsychological test performance. We used a broad neuropsychological test battery to assess 59 outpatients with work-related stress complaints (without major depression) and 59 healthy controls. We matched the patients and controls pairwise by sex, age and educational level. Compared to controls, patients generally showed mildly reduced performance across all the measured domains of the neuropsychological test battery. However, only three comparisons reached statistical significance (p working memory. There were no statistical significant associations between self-reported perceived stress level and neuropsychological test performance. In conclusion, we recommend that cognitive functions should be considered when evaluating patients with work-related stress complaints, especially when given advice regarding return to work. Since this study had a cross-sectional design, it is still uncertain whether the impairments are permanent. Further study is required to establish causal links between work-related stress and cognitive deficits.

  8. HIV testing among men who have sex with men in Tijuana, Mexico: a cross-sectional study.

    Science.gov (United States)

    Pines, Heather A; Goodman-Meza, David; Pitpitan, Eileen V; Torres, Karla; Semple, Shirley J; Patterson, Thomas L

    2016-02-04

    HIV testing is critical to the delivery of comprehensive HIV prevention and care services, yet coverage of sexual minorities by HIV testing programmes remains insufficient in many low- and middle-income countries, including Mexico. The objective of this study was to identify the prevalence and correlates of HIV testing among men who have sex with men (MSM) in Tijuana, Mexico. We conducted a cross-sectional study (2012-2013) among 189 MSM recruited via respondent-driven sampling (RDS). RDS-weighted logistic regression was used to identify correlates of prior HIV testing. RDS-adjusted prevalence of prior and recent (≤ 12 months) HIV testing was 63.5% (95% CI 51.9% to 73.5%) and 36.8% (95% CI 25.4% to 46.4%), respectively. Prior HIV testing was positively associated with older age (adjusted OR (AOR)=1.09, 95% CI 1.04 to 1.15), being born in Tijuana (AOR=2.68, 95% CI 1.05 to 6.86), higher levels of education (AOR=2.65, 95% CI 1.08 to 6.53), identifying as homosexual or gay (AOR=3.73, 95% CI 1.48 to 9.42), being more 'out' about having sex with men (AOR=1.28, 95% CI:1.02 to 1.62), and a history of sexual abuse (AOR=3.24, 95% CI 1.06 to 9.86). Prior HIV testing was negatively associated with reporting more condomless anal intercourse acts (past 2 months) (AOR=0.95, 95% CI 0.92 to 0.98) and greater internalised homophobia (AOR=0.92, 95% CI 0.86 to 0.99). Our findings indicate an urgent need for expanded HIV testing services for MSM in Tijuana. Innovative, non-stigmatising, confidential HIV testing interventions targeted at young, less educated, migrant and non-gay identifying MSM may facilitate HIV testing and timely linkage to HIV care and treatment within this population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  9. Uniaxial Compressive Constitutive Relationship of Concrete Confined by Special-Shaped Steel Tube Coupled with Multiple Cavities.

    Science.gov (United States)

    Wu, Haipeng; Cao, Wanlin; Qiao, Qiyun; Dong, Hongying

    2016-01-29

    A method is presented to predict the complete stress-strain curves of concrete subjected to triaxial stresses, which were caused by axial load and lateral force. The stress can be induced due to the confinement action inside a special-shaped steel tube having multiple cavities. The existing reinforced confined concrete formulas have been improved to determine the confinement action. The influence of cross-sectional shape, of cavity construction, of stiffening ribs and of reinforcement in cavities has been considered in the model. The parameters of the model are determined on the basis of experimental results of an axial compression test for two different kinds of special-shaped concrete filled steel tube (CFT) columns with multiple cavities. The complete load-strain curves of the special-shaped CFT columns are estimated. The predicted concrete strength and the post-peak behavior are found to show good agreement within the accepted limits, compared with the experimental results. In addition, the parameters of proposed model are taken from two kinds of totally different CFT columns, so that it can be concluded that this model is also applicable to concrete confined by other special-shaped steel tubes.

  10. Uniaxial Compressive Constitutive Relationship of Concrete Confined by Special-Shaped Steel Tube Coupled with Multiple Cavities

    Directory of Open Access Journals (Sweden)

    Haipeng Wu

    2016-01-01

    Full Text Available A method is presented to predict the complete stress-strain curves of concrete subjected to triaxial stresses, which were caused by axial load and lateral force. The stress can be induced due to the confinement action inside a special-shaped steel tube having multiple cavities. The existing reinforced confined concrete formulas have been improved to determine the confinement action. The influence of cross-sectional shape, of cavity construction, of stiffening ribs and of reinforcement in cavities has been considered in the model. The parameters of the model are determined on the basis of experimental results of an axial compression test for two different kinds of special-shaped concrete filled steel tube (CFT columns with multiple cavities. The complete load-strain curves of the special-shaped CFT columns are estimated. The predicted concrete strength and the post-peak behavior are found to show good agreement within the accepted limits, compared with the experimental results. In addition, the parameters of proposed model are taken from two kinds of totally different CFT columns, so that it can be concluded that this model is also applicable to concrete confined by other special-shaped steel tubes.

  11. Factors associated with HIV testing among young men who have sex with men in Myanmar: a cross-sectional study.

    Science.gov (United States)

    Pham, Minh D; Aung, Poe Poe; Paing, Aye Kyawt; Pasricha, Naanki; Agius, Paul A; Tun, Waimar; Bajracharya, Ashish; Luchters, Stanley

    2017-11-01

    In Myanmar, men who have sex with men (MSM) experience high risk of HIV infection. However, access to HIV testing and prevention services remains a challenge among this marginalized population. The objective of this study was to estimate population prevalence and correlates of prior HIV testing among young MSM (YMSM) and informs the development of HIV testing and intervention programmes that respond to the specific needs of this population. Five hundred and eighty-five YMSM aged 18 to 24 years were recruited using respondent-driven sampling (RDS) in a cross-sectional survey conducted in six townships of Myanmar. RDS-adjusted population estimates were calculated to estimate prevalence of HIV testing; RDS-weighted logistic regression was used to examine correlates of HIV testing in the past 6 months and in a lifetime. There were 12 participants who reported receiving a HIV-positive test; of those, five were tested in the past 6 months. The RDS-weighted prevalence estimates of lifetime (any prior) HIV testing was 60.6% (95% CI: 53.3% to 66.4%) and of recent (≤ 6 months) HIV testing was 50.1% (95% CI: 44.1% to 55.5%). In multivariable analysis, sexual identity was associated with lifetime but not recent HIV testing. Lifetime and recent HIV testing were associated with having three or more male sexual partners in the past 12 months (adjusted ORs (aORs) = 2.28, 95% CIs: 1.21 to 4.32 and 2.69, 95% CI: 1.59 to 4.56), having good HIV-related knowledge (aORs = 1.96, 95% CIs: 1.11 to 3.44 and 1.77, 95% CI: 1.08 to 2.89), reporting high HIV testing self-efficacy (aORs = 13.5, 95% CIs: 6.0 to 30.1 and 9.81, 95% CI: 4.27 to 22.6) and having access to and use of non-HIV health-related services in the past 12 months (aORs = 13.2, 95% CIs: 6.85 to 25.6 and 7.15, 95% CI: 4.08 to 12.5) respectively. HIV testing coverage among YMSM aged 18 to 24 years old in Myanmar is still suboptimal. Integrated HIV testing and prevention services in existing health service

  12. BOOK REVIEW: Advanced Diagnostics for Magnetic and Inertial Confinement Fusion

    Science.gov (United States)

    Stott, PE; Wootton, A.; Gorini, G.; Sindoni, E.; Batani, D.

    2003-02-01

    parameters approach ignition. Spectroscopic systems and their recent developments are well represented, whereas edge diagnostics are somewhat thin on the ground. A dedicated section is devoted to the latest tests on radiation effects and technological issues. The problems of damage to optical components and the difficulties presented by the determination of the tritium inventory are described. In the last part, the new diagnostic systems of the most recent experiments (under construction or recently operated) are reported. Various aspects of some diagnostics not included in the three previous sections are also covered, with particular emphasis on microwaves and infrared diagnostics. The book is well suited for specialists and, more generally, for people involved in nuclear fusion, who need information about the most recent developments in the field of plasma diagnostics. The papers cover many aspects of the challenges and possible solutions for performing measurements in fusion machines approaching reactor conditions. On the other hand, the contributions are in general quite advanced and would be challenging for people without a significant background in plasma diagnostics and nuclear fusion. The quality of the paper is more than satisfactory both from the point of view of clarity and of graphics. Moreover, at the beginning of the book, several papers make a considerable effort to put diagnostic issues in the wider context of present day nuclear fusion research. For those topics, which are too involved to be completely described in a conference contribution, in general adequate references are provided for deeper investigation. A Murari Approximately one third of the papers included in this volume deal with diagnostics related to inertial confinement fusion plasmas (i.e., laser-produced plasmas and pulsed-power). These papers discuss recent developments in charged particle diagnostics, neutron diagnostics, optical and x-ray measurements along with laser and particle probing

  13. Confinement dynamics in the reversed field pinch

    International Nuclear Information System (INIS)

    Schoenberg, K.F.

    1988-01-01

    The study of basic transport and confinement dynamics is central to the development of the reversed field pinch (RFP) as a confinement concept. Thus, the goal of RFP research is to understand the connection between processes that sustain the RFP configuration and related transport/confinement properties. Recently, new insights into confinement have emerged from a detailed investigation of RFP electron and ion physics. These insights derive from the recognition that both magnetohydrodynamic (MHD) and electron kinetic effects play an important and strongly coupled role in RFP sustainment and confinement dynamics. In this paper, we summarize the results of these studies on the ZT-40M experiment. 8 refs

  14. Cylindrical confinement of semiflexible polymers.

    Science.gov (United States)

    Vázquez-Montejo, Pablo; McDargh, Zachary; Deserno, Markus; Guven, Jemal

    2015-06-01

    Equilibrium states of a closed semiflexible polymer binding to a cylinder are described. This may be either by confinement or by constriction. Closed completely bound states are labeled by two integers: the number of oscillations, n, and the number of times it winds the cylinder, p, the latter being a topological invariant. We examine the behavior of these states as the length of the loop is increased by evaluating the energy, the conserved axial torque, and the contact force. The ground state for a given p is the state with n=1; a short loop with p=1 is an elliptic deformation of a parallel circle; as its length increases it elongates along the cylinder axis with two hairpin ends. Excited states with n≥2 and p=1 possess n-fold axial symmetry. Short (long) loops possess energies ≈pE(0)(nE(0)), with E(0) the energy of a circular loop with same radius as the cylinder; in long loops the axial torque vanishes. Confined bound excited states are initially unstable; however, above a critical length each n-fold state becomes stable: The folded hairpin cannot be unfolded. The ground state for each p is also initially unstable with respect to deformations rotating the loop off the surface into the interior. A closed planar elastic curve aligned along the cylinder axis making contact with the cylinder on its two sides is identified as the ground state of a confined loop. Exterior bound states behave very differently, if free to unbind, as signaled by the reversal in the sign of the contact force. If p=1, all such states are unstable. If p≥2, however, a topological obstruction to complete unbinding exists. If the loop is short, the bound state with p=2 and n=1 provides a stable constriction of the cylinder, partially unbinding as the length is increased. This motif could be relevant to an understanding of the process of membrane fission mediated by dynamin rings.

  15. Factors associated with continuing emergence of β-thalassemia major despite prenatal testing: a cross-sectional survey

    Directory of Open Access Journals (Sweden)

    Al Sabbah H

    2017-09-01

    Full Text Available Haleama Al Sabbah,1 Sarah Khan,1 Abdallah Hamadna,2 Lamia Abu Ghazaleh,2 Anwar Dudin,2 Bashar Adnan Karmi3 1College of Natural and Health Sciences, Zayed University, Dubai, UAE; 2Faculty of Medicine, An-Najah National University, Nablus, Palestine; 3Thalassemia Patients’ Friends Society, Ramallah, Palestine Purpose: Health care initiatives focusing on prenatal testing and premarital genetic screening aiming to reduce the incidence of β-thalassemia have emerged during the last decade. In Palestine, 4% of the population are known thalassemia carriers with new cases continuing to appear despite the availability of prenatal testing. This study aims to identify factors that influence the decision to retain or abort fetuses affected by β-thalassemia in Palestine. Methods: Convenience sampling was used to select 32 women (72 fetuses who were at risk of having a baby with β-thalassemia. A questionnaire on prenatal testing, test results, pregnancy outcomes, and factors influencing the decision to terminate the pregnancy were used for this cross-sectional study. The data were analyzed using SPSS version 17. Results: Among the fetuses screened, 36 (50% were thalassemia carriers and 20 (28% had β-thalassemia; 17 (85% affected fetuses were aborted. Religious beliefs were the most cited reason for opposing abortion while prior experience with β-thalassemia patients and awareness programs promoted abortions. Mothers who opted to retain an affected fetus had modest educational attainment. Higher educational level was significantly associated with the decision to abort an affected fetus (p<0.05. Conclusion: A religious consensus is needed on the abortion of fetuses affected by β-thalassemia. Improving female education and increasing awareness on thalassemia could help reduce the incidence of β-thalassemia in Palestine and around the world. Keywords: abortion, Islam, fetus, awareness

  16. Confinement of high temperature plasmas

    International Nuclear Information System (INIS)

    Bass, R.W.; Ferguson, H.R.; Fletcher, H.J.; Gardner, J.H.; Harrison, B.K.; Larsen, K.M.

    1980-01-01

    A high temperature plasma is confined in the shape of a topological torus by a topologically stable magnetic field which is everywhere constant on and tangent to the surface of the torus. There are exactly an even finite number of closed magnetic field lines on the plasma surface and all other magnetic field lines on the surface are asymptotic to the closed field lines. This magnetic field configuration is achieved by a set of current carrying conductors appropriately arranged with respect to the plasma and carrying suitably selected currents

  17. Frictional properties of confined polymers

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, Vladimir N; Persson, Bo N J

    2008-01-01

    We present molecular dynamics friction calculations for confined hydrocarbon solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: a) polymer sliding against a hard substrate, and b) polymer sliding on polymer. In the first setup the shear stresses are relatively...... independent of molecular length. For polymer sliding on polymer the friction is significantly larger, and dependent on the molecular chain length. In both cases, the shear stresses are proportional to the squeezing pressure and finite at zero load, indicating an adhesional contribution to the friction force...

  18. Results from deuterium-tritium tokamak confinement experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hawryluk, R.J.

    1997-02-01

    Recent scientific and technical progress in magnetic fusion experiments has resulted in the achievement of plasma parameters (density and temperature) which enabled the production of significant bursts of fusion power from deuterium-tritium fuels and the first studies of the physics of burning plasmas. The key scientific issues in the reacting plasma core are plasma confinement, magnetohydrodynamic (MHD) stability, and the confinement and loss of energetic fusion products from the reacting fuel ions. Progress in the development of regimes of operation which have both good confinement and are MHD stable have enabled a broad study of burning plasma physics issues. A review of the technical and scientific results from the deuterium-tritium experiments on the Joint European Torus (JET) and the Tokamak Fusion Test Reactor (TFTR) is given with particular emphasis on alpha-particle physics issues.

  19. Results from deuterium-tritium tokamak confinement experiments

    International Nuclear Information System (INIS)

    Hawryluk, R.J.

    1997-02-01

    Recent scientific and technical progress in magnetic fusion experiments has resulted in the achievement of plasma parameters (density and temperature) which enabled the production of significant bursts of fusion power from deuterium-tritium fuels and the first studies of the physics of burning plasmas. The key scientific issues in the reacting plasma core are plasma confinement, magnetohydrodynamic (MHD) stability, and the confinement and loss of energetic fusion products from the reacting fuel ions. Progress in the development of regimes of operation which have both good confinement and are MHD stable have enabled a broad study of burning plasma physics issues. A review of the technical and scientific results from the deuterium-tritium experiments on the Joint European Torus (JET) and the Tokamak Fusion Test Reactor (TFTR) is given with particular emphasis on alpha-particle physics issues

  20. Nonlinearity of mechanical damping and stiffness of a spring-suspended sectional model system for wind tunnel tests

    Science.gov (United States)

    Gao, Guangzhong; Zhu, Ledong

    2015-10-01

    The wind tunnel test of spring-suspended sectional models (SSSM) is an important means in the research of wind engineering, which is very frequently employed to check the performances of flutter and vortex-induced resonance of bridges as well as to identify the various aerodynamic and aeroelastic parameters of bridge components, such as aerodynamic derivatives of self-excited forces. However, in practice, the mechanical damping ratios and natural frequencies of SSSM system are prevailingly supposed to be constant in the whole procedure of a test. This assumption often leads to notable errors of the test results or dispersion of the identified aerodynamic parameters because the mechanical damping ratios and natural frequencies of SSSM system are proved to vary in fact to some extent with the change of oscillating amplitude. On that account, the mechanical nonlinearity of SSSM system is investigated and discussed in this paper by taking a flat-closed box section as a research background. The conventional linear model is firstly proved to fail to predict precisely the long-duration free decay responses of the SSSM system. The formulae of equivalent linearization approximation (ELA) are then derived by using a multiple-scale method to model the mechanical nonlinearities in the first-order approximate sense, and a time-domain system identification method is proposed on this basis to identify equivalent amplitude-dependent (EAD) damping ratio and frequency. The proposed ELA and nonlinear system identification methods are then found to be precise enough to model the mechanical nonlinearities of SSSM system. The characteristics of EAD damping ratio and frequency of both the bending and torsional modes are then discussed in detail. It is then found that the major energy dissipation of SSSM vibrations at both the bending and torsional modes generally comes from the combined effect of viscous damping and quadratic damping. However, for the vibration at the bending mode with

  1. Magnetic confinement fusion energy research

    Energy Technology Data Exchange (ETDEWEB)

    Grad, H

    1977-03-01

    Controlled Thermonuclear Fusion offers probably the only relatively clean energy solution with completely inexhaustible fuel and unlimited power capacity. The scientific and technological problem consists in magnetically confining a hot, dense plasma (pressure several to hundreds of atmospheres, temperature 10/sup 8/ degrees or more) for an appreciable fraction of a second. The scientific and mathematical problem is to describe the behavior, such as confinement, stability, flow, compression, heating, energy transfer and diffusion of this medium in the presence of electromagnetic fields just as we now can for air or steam. Some of the extant theory consists of applications, routine or ingenious, of known mathematical structures in the theory of differential equations and in traditional analysis. Other applications of known mathematical structures offer surprises and new insights: the coordination between sub-supersonic and elliptic-hyperbolic is fractured; supersonic propagation goes upstream; etc. Other completely nonstandard mathematical structures with significant theory are being rapidly uncovered (and somewhat less rapidly understood) such as non-elliptic variational equations and new types of weak solutions. It is these new mathematical structures which one should expect to supply the foundation for the next generation's pure mathematics, if history is a guide. Despite the substantial effort over a period of some twenty years, there are still basic and important scintific and mathematical discoveries to be made, lying just beneath the surface.

  2. Knowledge, attitude and practice towards voluntary counseling and testing among university students in North West Ethiopia: a cross sectional study.

    Science.gov (United States)

    Addis, Zelalem; Yalew, Aregawi; Shiferaw, Yitayal; Alemu, Abebe; Birhan, Wubet; Mathewose, Biniam; Tachebele, Belayenesh

    2013-08-02

    Voluntary counseling and testing (VCT) is one among different approaches which have been implemented as an attempt to slow the spread of HIV infection and minimize its impact at the individual, family and society level. VCT is perceived to be an effective strategy in risk reduction among sexually active young people like tertiary level students. Ethiopia as a country with high burden of HIV started responding to the epidemic by preparing and updating guidelines on VCT. The objective of this study was to assess the level of knowledge, attitude and practice of Voluntary Counseling and Testing (VCT) for HIV among university students in North West Ethiopia. A cross sectional study was conducted from February to May 2010 using a stratified sampling method to enroll students from different faculties into the study. A total of 330 university students filled in a self-administered questionnaire with response rate of 97.3%. Main outcome measures included level of knowledge, attitude and practice of VCT for HIV. A chi-square test was used to determine an association between a number of independent factors and dependant variables. About 66.1% of the study participants were males with a mean age of 20 years. Majority (75.6%) of the respondents were Orthodox with 63% reported living in urban areas before joining the university. From the study participants 86.3% were knowledgeable on VCT, 73.3% had positive attitude towards VCT for HIV and 61.8% had had VCT for HIV in the past. Previous residence before joining the university, level of education, sex and religion were among the sociodemographic variables that showed statistically significant association with the one or more of the outcome variables. Fear of positive results, stigma and discrimination following the positive results were reported as main barriers for VCT uptake. The findings reveal important barriers for VCT uptake and suggest strategies to reduce stigma and discrimination.

  3. Ion thermal confinement in the TFTR enhanced confinement regime

    Energy Technology Data Exchange (ETDEWEB)

    Fonck, R.J.; Howell, R.; Jaehnig, K.; Roquemore, L.; Schilling, G.; Scott, S.; Zarnstorff, M.C.; Bitter, M.; Bush, C.; Goldston, R.

    1988-12-01

    Measurements of the plasma ion temperature and toroidal rotation speed profiles have allowed the study of ion thermal transport in the TFTR hot ion enhanced confinement regime. Central ion temperatures up to 30 keV and rotation speeds up to 8 x 10/sup 5/ m/sec have been confirmed with new diagnostic measurements, and the ion thermal diffusivity is found to be non-neoclassical and comparable to the anomalous electron thermal diffusivity. The dominant effects of strong rotation are the down-shifting of the neutral beam energies in the plasma frame, which results in reduced ion and electron heating on axis, and the presence of off-axis ion heating from viscous damping of the plasma rotation. 14 refs., 3 figs.

  4. Associations between cadmium exposure and neurocognitive test scores in a cross-sectional study of US adults

    Science.gov (United States)

    2013-01-01

    Background Low-level environmental cadmium exposure and neurotoxicity has not been well studied in adults. Our goal was to evaluate associations between neurocognitive exam scores and a biomarker of cumulative cadmium exposure among adults in the Third National Health and Nutrition Examination Survey (NHANES III). Methods NHANES III is a nationally representative cross-sectional survey of the U.S. population conducted between 1988 and 1994. We analyzed data from a subset of participants, age 20–59, who participated in a computer-based neurocognitive evaluation. There were four outcome measures: the Simple Reaction Time Test (SRTT: visual motor speed), the Symbol Digit Substitution Test (SDST: attention/perception), the Serial Digit Learning Test (SDLT) trials-to-criterion, and the SDLT total-error-score (SDLT-tests: learning recall/short-term memory). We fit multivariable-adjusted models to estimate associations between urinary cadmium concentrations and test scores. Results 5662 participants underwent neurocognitive screening, and 5572 (98%) of these had a urinary cadmium level available. Prior to multivariable-adjustment, higher urinary cadmium concentration was associated with worse performance in each of the 4 outcomes. After multivariable-adjustment most of these relationships were not significant, and age was the most influential variable in reducing the association magnitudes. However among never-smokers with no known occupational cadmium exposure the relationship between urinary cadmium and SDST score (attention/perception) was significant: a 1 μg/L increase in urinary cadmium corresponded to a 1.93% (95%CI: 0.05, 3.81) decrement in performance. Conclusions These results suggest that higher cumulative cadmium exposure in adults may be related to subtly decreased performance in tasks requiring attention and perception, particularly among those adults whose cadmium exposure is primarily though diet (no smoking or work based cadmium exposure). This

  5. Runaway electrons and magnetic island confinement

    Science.gov (United States)

    Boozer, Allen H.

    2016-08-01

    The breakup of magnetic surfaces is a central feature of ITER planning for the avoidance of damage due to runaway electrons. Rapid thermal quenches, which lead to large accelerating voltages, are thought to be due to magnetic surface breakup. Impurity injection to avoid and to mitigate both halo and runaway electron currents utilizes massive gas injection or shattered pellets. The actual deposition is away from the plasma center, and the breakup of magnetic surfaces is thought to spread the effects of the impurities across the plasma cross section. The breakup of magnetic surfaces would prevent runaway electrons from reaching relativistic energies were it not for the persistence of non-intercepting flux tubes. These are tubes of magnetic field lines that do not intercept the walls. In simulations and in magnetic field models, non-intercepting flux tubes are found to persist near the magnetic axis and in the cores of magnetic islands even when a large scale magnetic surface breakup occurs. As long as a few magnetic surfaces reform before all of the non-intercepting flux tubes dissipate, energetic electrons confined and accelerated in these flux tubes can serve as the seed electrons for a transfer of the overall plasma current from thermal to relativistic carriers. The acceleration of electrons is particularly strong because of the sudden changes in the poloidal flux that naturally occur in a rapid magnetic relaxation. The physics of magnetic islands as non-intercepting flux tubes is studied. Expressions are derived for (1) the size of islands required to confine energetic runaway electrons, (2) the accelerating electric field in an island, (3) the increase or reduction in the size of an island by the runaway electron current, (4) the approximate magnitude of the runaway current in an island, and (5) the time scale for the evolution of an island.

  6. Methyl group dynamics in a confined glass

    OpenAIRE

    Moreno, A. J.; Colmenero, J.; Alegría, A.; Alba-Simionesco, C.; Dosseh, G.; Morineau, D.; Frick, B.

    2002-01-01

    We present a neutron scattering investigation on methyl group dynamics in glassy toluene confined in mesoporous silicates of different pore sizes. The experimental results have been analysed in terms of a barrier distribution model, such a distribution following from the structural disorder in the glassy state. Confinement results in a strong decreasing of the average rotational barrier in comparison to the bulk state. We have roughly separated the distribution for the confined state in a bul...

  7. Quark confinement in a constituent quark model

    International Nuclear Information System (INIS)

    Langfeld, K.; Rho, M.

    1995-01-01

    On the level of an effective quark theory, we define confinement by the absence of quark anti-quark thresholds in correlation function. We then propose a confining Nambu-Jona-Lasinio-type model. The confinement is implemented in analogy to Anderson localization in condensed matter systems. We study the model's phase structure as well as its behavior under extreme conditions, i.e. high temperature and/or high density

  8. Quark confinement in a constituent quark model

    Energy Technology Data Exchange (ETDEWEB)

    Langfeld, K.; Rho, M. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique

    1995-07-01

    On the level of an effective quark theory, we define confinement by the absence of quark anti-quark thresholds in correlation function. We then propose a confining Nambu-Jona-Lasinio-type model. The confinement is implemented in analogy to Anderson localization in condensed matter systems. We study the model`s phase structure as well as its behavior under extreme conditions, i.e. high temperature and/or high density.

  9. Confined subdiffusion in three dimensions

    International Nuclear Information System (INIS)

    Qin Shan-Lin; He Yong

    2014-01-01

    Three-dimensional (3D) Fick's diffusion equation and fractional diffusion equation are solved for different reflecting boundaries. We use the continuous time random walk model (CTRW) to investigate the time-averaged mean square displacement (MSD) of a 3D single particle trajectory. Theoretical results show that the ensemble average of the time-averaged MSD can be expressed analytically by a Mittag—Leffler function. Our new expression is in agreement with previous formulas in two limiting cases: <δ 2 -bar> ∼ Δ in short lag time and <δ 2 -bar> ∼ Δ 1-α in long lag time. We also simulate the experimental data of mRNA diffusion in living E. coli using a 3D CTRW model under confined and crowded conditions. The simulation results are well consistent with experimental results. The calculations of power spectral density (PSD) further indicate the subdiffsive behavior of an individual trajectory. (general)

  10. Colour screening and quark confinement

    International Nuclear Information System (INIS)

    Mack, G.

    1978-03-01

    It is proposed that in Quantum Chromodynamics the colour charge of gluons and of anything with zero triality is screened by a dynamical Higgs mechanism with Higgs scalars made out of gluons. The center Z 3 of the gauge group SU(3) is left unbroken in this way, and single quarks, which have nonzero triality, cannot be screened. Long range forces between them persist therefore. Given that the Higgs mechanism produces a mass gap, the most favorable configuration of field lines between e.g. quark and antiquark will be in strings analogous to magnetic field lines in a superconductor. The strings confine the quarks. The screening mechanism, on the other hand, produces not only the mass gap (which leads to string formation) but is also responsible for saturation of forces, i.e. absence of bound states of six quarks etc. (orig.) [de

  11. Confined subdiffusion in three dimensions

    Science.gov (United States)

    Qin, Shan-Lin; He, Yong

    2014-11-01

    Three-dimensional (3D) Fick's diffusion equation and fractional diffusion equation are solved for different reflecting boundaries. We use the continuous time random walk model (CTRW) to investigate the time-averaged mean square displacement (MSD) of a 3D single particle trajectory. Theoretical results show that the ensemble average of the time-averaged MSD can be expressed analytically by a Mittag—Leffler function. Our new expression is in agreement with previous formulas in two limiting cases: in short lag time and in long lag time. We also simulate the experimental data of mRNA diffusion in living E. coli using a 3D CTRW model under confined and crowded conditions. The simulation results are well consistent with experimental results. The calculations of power spectral density (PSD) further indicate the subdiffsive behavior of an individual trajectory.

  12. Sex differences in urea breath test results for the diagnosis of Helicobacter pylori infection: a large cross-sectional study.

    Science.gov (United States)

    Eisdorfer, Ido; Shalev, Varda; Goren, Sophy; Chodick, Gabriel; Muhsen, Khitam

    2018-01-02

    Helicobacter pylori causes peptic ulcer disease and gastric cancer only in a subset of infected persons. Sex differences were shown in results of urea breath test (UBT), a commonly used test for the diagnosis of H. pylori infection. However, factors that might explain these differences, or affect UBT values, are not fully understood. We examined differences in UBT values between H. pylori-infected men and women while adjusting for background characteristics such as age, body mass index (BMI), and smoking. A cross-sectional study was undertaken using coded data from the computerized database of Maccabi Health Services in Israel. Included were adults examined for UBT during 2002-2012 and were found H. pylori positive (UBT > 3.5‰). Multivariable linear mixed models were performed to assess the relationship between sex and UBT quantitative results, while adjusting for background characteristics. A total of 76,403 patients were included (52% of examined patients during the study period). Adjusted mean UBT value was significantly higher in women 33.8‰ (95% CI 33.4, 34.1) than in men 24.9‰ (95% CI 24.5, 25.3). A significant (P sex and smoking, showing diminished sex-differences in UBT results in smokers. Adjusted mean UBT values increased significantly with age and decreased with BMI, and it was higher in people who lived in low vs high socioeconomic status communities and lower in smokers vs non-smokers. Systemic differences exist between men and women in quantitative UBT results. Host-related and environmental factors might affect UBT quantitative results. These findings have clinical implications regarding confirmation of the success of H. pylori eradication after treatment in various subgroups.

  13. Properties of radio-frequency heated argon confined uranium plasmas

    International Nuclear Information System (INIS)

    Roman, W.C.

    1976-01-01

    An experimental investigation was performed to aid in determining the characteristics of uranium plasma core reactors. Pure uranium hexafluoride (UF 6 ) was injected into an argon-confined, steady-state, rf-heated plasma, within a fused-silica peripheral wall test chamber. Exploratory tests conducted using an 80 kW rf facility and different test chamber flow configurations permitted selection of the configuration demonstrating the best confinement characteristics and minimum uranium compound wall coating. The test chamber selected was 10-cm-long and 5.7-cm-inside diameter; operating pressures were up to 12 atm. A UF 6 handling and feeder system to provide a controlled and steady flow of heated UF 6 at temperatures up to 500 0 K and mass flow rates up to 0.21 g/s was employed

  14. 2XIIB plasma confinement experiments

    International Nuclear Information System (INIS)

    Coensgen, F.H.; Clauser, J.F.; Correll, D.L.

    1976-01-01

    This paper reports results of 2XIIB neutral-beam injection experiments with plasma-stream stabilization. The plasma stream is provided either by a pulsed plasma generator located on the field lines outside the plasma region or by ionization of neutral gas introduced at the mirror throat. In the latter case, the gas is ionized by the normal particle flux through the magnetic mirror. A method of plasma startup and sustenance in a steady-state magnetic field is reported in which the plasma stream from the pulsed plasma generator serves as the initial target for the neutral beams. After an energetic plasma of sufficient density is established, the plasma generator stream is replaced by the gas-fed stream. Lifetimes of the stabilized plasma increase with plasma temperature in agreement with the plasma stabilization of the drift-cyclotron loss-cone mode. The following plasma parameters are attained using the pulsed plasma generator for stabilization: n approximately 5 x 10 13 cm -3 , anti W/sub i/ approximately 13 keV, T/sub e/ = 140 eV, and ntau/sub p/ approximately 7 x 10 10 cm -3 .s. With the gas feed, the mean deuterium ion energy is 9 keV and the peak density n approximately 10 14 cm -3 . In the latter case, the energy confinement parameter reaches ntau/sub E/ = 7 x 10 10 cm -3 .s, and the particle confinement parameter reaches ntau/sub p/ = 1 x 10 11 cm -3 .s

  15. Dynamics and reactivity of confined water

    International Nuclear Information System (INIS)

    Musat, R.

    2008-01-01

    In the context of new sustainable energy sources quest, the nuclear energy remains a key solution. However, with the development of nuclear technology, problems relating to nuclear waste disposal arise; thus, the radiolysis of water in confined media is extremely important with respect to matters related to long time storage of nuclear waste. Studies in model porous media would allow the projection of a confined water radiolysis simulator. A first step in this direction was made by studying the radiolysis of water confined in Vycor and CPG glasses; this study continues the trend set and investigates the effects of confinement in metal materials upon the water radiolysis allowing the understanding of metal - water radiation induced corrosion. A further/complete understanding of the radiolytic process under confinement requires knowledge of the effect of confinement upon the dynamics of confined molecules and on the evolution of the species produced upon ionizing radiation. In this respect, we have used the OH vibrator as a probe of the hydrogen bond network properties and thus investigated the dynamics of confined water using IR time resolved spectroscopy. The evolution of the hydrated electron under confinement was studied on a nano and picosecond time scale using UV pump - visible probe technique and single shot spectroscopy. (author) [fr

  16. Factors influencing the uptake of voluntary HIV counseling and testing in rural Ethiopia: a cross sectional study

    Directory of Open Access Journals (Sweden)

    Hailay D. Teklehaimanot

    2016-03-01

    Full Text Available Abstract Background Voluntary counseling and testing (VCT has been one of the key policy responses to the HIV/AIDS epidemic in Ethiopia. However, the utilization of VCT has been low in the rural areas of the country. Understanding factors influencing the utilization of VCT provides information for the design of context based appropriate strategies that aim to improve utilization. This study examined the effects of socio-demographic and behavioral factors, and health service characteristics on the uptake of VCT among rural adults in Ethiopian. Methods/design This study was designed as a cross sectional study. Data from 11,919 adults (6278 women aged 15–49 years and 5641 men aged 15–59 years residing in rural areas of Ethiopia who participated in a national health extension program evaluation were used for this study. The participants were selected from ten administrative regions using stratified multi-stage cluster sampling. Multivariate logistic regression analysis was performed accounting for factors associated with the use of VCT service. Results Overall, men (28 % were relatively more likely to get tested for HIV than women (23.7 % through VCT. Rural men and women who were young and better educated, who perceived having small risk of HIV infection, who had comprehensive knowledge, no stigmatization attitude and discussed about HIV/AIDS with their partner, and model-family were more likely to undergone VCT. Regional state was also strongly associated with VCT utilization in both men and women. Rural women who belonged to households with higher socio-economic status, non-farming occupation, female-headed household and located near health facility, and who visited health extension workers and participated in community conversation were more likely to use VCT. Among men, agrarian lifestyle was associated with VCT use. Conclusions Utilization of VCT in the rural communities is low, and socio-economic, behavioral and health service factors

  17. Generating equilateral random polygons in confinement III

    International Nuclear Information System (INIS)

    Diao, Y; Ernst, C; Montemayor, A; Ziegler, U

    2012-01-01

    In this paper we continue our earlier studies (Diao et al 2011 J. Phys. A: Math. Theor. 44 405202, Diao et al J. Phys. A: Math. Theor. 45 275203) on the generation methods of random equilateral polygons confined in a sphere. The first half of this paper is concerned with the generation of confined equilateral random walks. We show that if the selection of a vertex is uniform subject to the position of its previous vertex and the confining condition, then the distributions of the vertices are not uniform, although there exists a distribution such that if the initial vertex is selected following this distribution, then all vertices of the random walk follow this same distribution. Thus in order to generate a confined equilateral random walk, the selection of a vertex cannot be uniform subject to the position of its previous vertex and the confining condition. We provide a simple algorithm capable of generating confined equilateral random walks whose vertex distribution is almost uniform in the confinement sphere. In the second half of this paper we show that any process generating confined equilateral random walks can be turned into a process generating confined equilateral random polygons with the property that the vertex distribution of the polygons approaches the vertex distribution of the walks as the polygons get longer and longer. In our earlier studies, the starting point of the confined polygon is fixed at the center of the sphere. The new approach here allows us to move the starting point of the confined polygon off the center of the sphere. (paper)

  18. QCD confinement and the meson spectrum

    CERN Document Server

    González, P; Valcarce, A; Vijande, J

    2003-01-01

    From QCD and lattice calculations two specific forms of quark confining potential, a strict linear and a screened linear confinement, come out. Both forms of the potential, implemented by the one gluon exchange interaction, are applied to the description of heavy quarkonia: cc and bb. Applications to light hadrons, mesons and baryons, are also commented. (11 refs).

  19. Nanorheology of strongly confined oligomeric lubricants

    NARCIS (Netherlands)

    Manias, E.; Brinke, G. ten; Hadziioannou, G.

    1996-01-01

    Lubricant films confined in nanometric slit pores and subjected to shear flow are studied by non-equilibrium molecular dynamics in a planar Couette flow geometry. An inhomogeneous, layered density profile is developed near the confining surfaces and the shape of the velocity profile across the pore

  20. Structure of polymer chains under confinement

    Indian Academy of Sciences (India)

    Single chain form factor was observed both for bulk and confined chains using the condition of zero average contrast. Our measurements on neutral polymer chains are in agreement with the theoretical predictions established by Daoud and de Gennes for chains confined in a cylindrical pore when the chains are entangled ...

  1. Climate conditions in bedded confinement buildings

    Science.gov (United States)

    Confinement buildings are utilized for finishing cattle to allow more efficient collection of animal waste and to buffer animals against adverse climatic conditions. Environmental data were obtained from a 29 m wide x 318 m long bedded confinement building with the long axis oriented east to west. T...

  2. Development of filter module for passive filtration and accident gas release confinement system for NPP

    International Nuclear Information System (INIS)

    Yelizarov, P.G.; Efanov, A.D.; Martynov, P.N.; Masalov, D.P.; Osipov, V.P.; Yagodkin, I.V.

    2005-01-01

    Full text of publication follows: One of the urgent problems of the safe NPP operation is air cleaning from radioactive aerosols and volatile iodine compounds under the accident operation conditions of NPP. A principally new passive accident gas release confinement system is used as the basis of the designs of new generation reactor power blocks under the-beyond-design-basis accident conditions with total loss of current. The basic structural component of the passive filtration system (PFS) is the filter-sorber being heated up to 300 deg. C. The filter-sorber represents a design consisting of 150 connected in parallel two-step filtering modules. The first step is intended to clean air from radioactive aerosols, the second one - to clean air from radioactive iodine and its volatile compounds. The filter-sorber is located in the upper point of the exterior protection shell. Due to natural convection, it provides confinement of r/a impurities and controlled steam-gas release from the inter-shell space into atmosphere. The basic specific design feature is the two-section design of the PFS filter module consisting of a coarse-cleaning section and a fine-cleaning section. A combination of layer-by-layer put filtering materials on the basis of glass fiber and metal fiber. The pilot PFS filter module specimen tests run in conditions modeling accident situation indicated that at a filtration rate of 0,3 cm/s the aerodynamic resistance of the module does not exceed 12 Pa, the filtration effectiveness equals 99,99 % in terms of aerosol, no less than 99,9% in terms of radioactive 131 I and no less than 99,0% in terms of organic compounds of iodine (CH 3 131 I); the dust capacity amounts to a value above 50 g/m 2 . The obtained results of tests comply with the design requirements imposed on the PFS filter-sorber module. (authors)

  3. Inertial Confinement Fusion R and D and Nuclear Proliferation

    International Nuclear Information System (INIS)

    Goldston, Robert J.

    2011-01-01

    In a few months, or a few years, the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory may achieve fusion gain using 192 powerful lasers to generate x-rays that will compress and heat a small target containing isotopes of hydrogen. This event would mark a major milestone after decades of research on inertial confinement fusion (ICF). It might also mark the beginning of an accelerated global effort to harness fusion energy based on this science and technology. Unlike magnetic confinement fusion (ITER, 2011), in which hot fusion fuel is confined continuously by strong magnetic fields, inertial confinement fusion involves repetitive fusion explosions, taking advantage of some aspects of the science learned from the design and testing of hydrogen bombs. The NIF was built primarily because of the information it would provide on weapons physics, helping the United States to steward its stockpile of nuclear weapons without further underground testing. The U.S. National Academies' National Research Council is now hosting a study to assess the prospects for energy from inertial confinement fusion. While this study has a classified sub-panel on target physics, it has not been charged with examining the potential nuclear proliferation risks associated with ICF R and D. We argue here that this question urgently requires direct and transparent examination, so that means to mitigate risks can be assessed, and the potential residual risks can be balanced against the potential benefits, now being assessed by the NRC. This concern is not new (Holdren, 1978), but its urgency is now higher than ever before.

  4. Forms of cohesion in confinement institutions

    Directory of Open Access Journals (Sweden)

    Ekaterina D. Slobodenyuk

    2015-12-01

    Full Text Available Objective to identify the diversity of cohesion forms in confinement institutions. Methods qualitative analyses based on indepth semistructured interviews. Results the study included adaptation of Western methodologies of the cohesion phenomenon analysis to the Russian reality and operationalization of the moral bases of group cohesion. This served as the bases for designing a guide for indepth semistructured interviews 10 interviews were conducted with people recently released from general and strict regime colonies. Content analysis of the interviews revealed a number of structural sections that demonstrate the diversity of cohesion forms alongside with one that is most meaningful to the prisoners and therefore the most well perceived and articulated by respondents. Analysis of the latter allowed to identify a set of groups showing different degree and nature of cohesion. By the degree of cohesion one can identify the poorly cohesive groups quotloutsquot moderately cohesive quotredsquot quotthievesquot and highly cohesive quotfightersquot. By the nature of cohesion in the prisonersrsquo community there are both groups united on the basis of social morality quotredsquot quotthievesquot and groups demonstrating a high degree of cohesion based on the social justice morality quotfightersquot. A detailed analysis of the latter group also showed that the cohesion can have both traits of morality social justice and features of social order moral. Scientific novelty using the sociopsychological theory of the moral motives in determining the bases of cohesion. Practical significance the research results can be applied for the development of sociopsychological techniques for the penal system reform.

  5. Effects of Predamaged Level on Confined HSC Columns

    Directory of Open Access Journals (Sweden)

    Ma Chau-Khun

    2017-01-01

    Full Text Available In the design of repair works for damaged concrete, an accurate and representative stress-strain model is of important. The stress-strain model for damaged high strength concrete (HSC repaired with post-tensioning steel straps confinement yet available, although the confining method has been proven to be effective in improving the performance of non-damaged HSC. A series of experimental test was carried out to investigate the stress-strain relationships of such concrete. A total of 24 HSC cylinders were compressed until certain damaged levels, then repaired by using steel straps. Two important parameters have been identified to have significant effects on the stress-strain relationship of such repaired concrete, namely the confining volumetric ratio and damaged levels. These parameters were incorporated into the development of stressstrain model, which later was shown to correlate well with the experimental results. This paper also has evidenced that existing stressstrain models of damaged concrete are not suitable to be directly applied to the design of repair works using post-tensioning steel straps confinement that produce external lateral stress on damaged columns before subsequent loading applied.

  6. Subsurface barrier design alternatives for confinement and controlled advection flow

    International Nuclear Information System (INIS)

    Phillips, S.J.; Stewart, W.E.; Alexander, R.G.; Cantrell, K.J.; McLaughlin, T.J.

    1994-02-01

    Various technologies and designs are being considered to serve as subsurface barriers to confine or control contaminant migration from underground waste storage or disposal structures containing radioactive and hazardous wastes. Alternatives including direct-coupled flood and controlled advection designs are described as preconceptual examples. Prototype geotechnical equipment for testing and demonstration of these alternative designs tested at the Hanford Geotechnical Development and Test Facility and the Hanford Small-Tube Lysimeter Facility include mobile high-pressure injectors and pumps, mobile transport and pumping units, vibratory and impact pile drivers, and mobile batching systems. Preliminary laboratory testing of barrier materials and additive sequestering agents have been completed and are described

  7. Theoretical and numerical analysis of reinforced concrete beams with confinement reinforcement

    OpenAIRE

    Delalibera, R. G.; Giongo, J. S.

    2008-01-01

    This paper discusses the use of confinement in over-reinforced concrete beams. This reinforcement consists of square stirrups, placed in the compression zone of the beam cross-section, in order to improve its ductility. A parametric numerical study is initially performed, using a finite element computational program that considers the material nonlinearities and the confinement effect. To investigate the influence of the transverse reinforcing ratio on the beam ductility, an experimental prog...

  8. Confinement of NORMAL- AND HIGH-STRENGTH CONCRETE by Shape Memory Alloy (SMA) Spirals

    Science.gov (United States)

    Gholampour, A.; Ozbakkaloglu, T.

    2018-01-01

    This paper presents the results of an experimental study on the axial compressive behaviour of normal- and high-strength concrete (NSC and HSC) confined by shape memory alloy (SMA) spirals. A spiral pitch space of 36 and 20 mm was used for SMA confinement of NSC and HSC columns, respectively. The confining pressure was applied on the concrete cylinders by SMA spirals that were prestrained at 0, 5.5, and 9.5%. The compression test results on the SMA-confined specimens indicate that the prestrain level of SMA significantly affects the axial compressive behaviour of both NSC and HSC. An increase in the level of prestrain leads to an increase in the peak axial stress and corresponding strain of SMA-confined concrete.

  9. Features and optimization approaches of the entrance section cooling gas flow of the IFMIF high flux test module

    Energy Technology Data Exchange (ETDEWEB)

    Arbeiter, F.; Gordeev, S.; Heinzel, V.; Ihli, T.; Leichtle, D. [Forschungszentrum Karlsruhe (Germany). Inst. fuer Reaktorsicherheit; Moeslang, A. [Forschungszentrum Karlsruhe (Germany). Inst. fuer Materialforschung

    2007-07-01

    The International Fusion Materials Irradiation Facility (IFMIF) is devised to contribute experimental evidence to an irradiated material properties database for candidate materials exposed to irradiation spectra and doses relevant for future fusion power reactors. Due to neutron fluxes generated by high energy deuterons reacting in a liquid lithium target, damage rates of 20-50 displacements per atom in one full power year can be achieved in steel specimens inside a volume of approximately 0.5 litres. The design of the High Flux Test Module developed at the Forschungszentrum Karlsruhe (FZK) allows for maximizing the space available in the high flux neutron field for material irradiation, while at the same time allowing precise adherence of the irradiation temperature of the specimen stacks. Since enhancement of the neutron irradiation requires to locate the specimens as close as possible to the neutron source, the design proposes thin container structures (obeying mechanical constraints), and flat coolant channels between the rigs. A helium gas flow is designated to remove the heat from the rigs to keep the required irradiation temperature, which may be chosen between 250-650 C. As a result of the thin container walls and the small channel dimensions, the helium cooling gas flow is characterized by low pressure, transitional Reynolds numbers and intermediate Mach numbers. Dedicated experimental investigations on such minichannel cooling gas flows have been conducted with the ITHEX helium loop facility. Results obtained by Laser Doppler Anemometry indicate a complex three dimensional evolution of the transitional laminarturbulent flow field in the hydraulic entrance section. In the short cooling channels, a relevant portion of the flow alongside the rigs is influenced by this developing region. Detailed knowledge of the flow development and the resulting heat transfer coefficients is necessary to optimize the flow channel inlet design and to avoid in

  10. Features and optimization approaches of the entrance section cooling gas flow of the IFMIF High Flux Test Module

    Energy Technology Data Exchange (ETDEWEB)

    Arbeiter, F. [Institut fuer Reaktorsicherheit, Forschungszentrum Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)], E-mail: arbeiter@irs.fzk.de; Gordeev, S.; Heinzel, V.; Ihli, T.; Leichtle, D. [Institut fuer Reaktorsicherheit, Forschungszentrum Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Moeslang, A. [Institut fuer Materialforschung I, Forschungszentrum Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Slobotchouk, V. [Institut fuer Reaktorsicherheit, Forschungszentrum Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2008-12-15

    The International Fusion Materials Irradiation Facility (IFMIF) is devised to contribute experimental evidence to an irradiated material properties database for candidate materials exposed to irradiation spectra and doses relevant for future fusion power reactors. Due to neutron fluxes generated by high-energy deuterons reacting in a liquid lithium target, damage rates of 20-50 displacements per atom in one full power year can be achieved in steel specimens inside a volume of approximately 0.5 L. The design of the high flux test module developed at the Forschungszentrum Karslruhe (FZK) allows for maximizing the space available in the high flux neutron field for material irradiation, while at the same time allowing precise adherence of the irradiation temperature of the specimen stacks. Since enhancement of the neutron irradiation requires placement of the specimens as close as possible to the neutron source, the design proposes thin container structures (obeying mechanical constraints) and flat coolant channels between the rigs. A helium gas flow is designated to remove the heat from the rigs to keep the required irradiation temperature, which may be chosen between 250 and 650 deg. C. As a result of the thin container walls and the small channel dimensions, the helium cooling gas flow is characterized by low pressure, transitional Reynolds numbers and intermediate Mach numbers. Dedicated experimental investigations on such minichannel cooling gas flows have been conducted with the ITHEX helium loop facility. Results obtained by laser Doppler anemometry indicate a complex three-dimensional evolution of the transitional laminar-turbulent flow field in the hydraulic entrance section. In the short cooling channels, a relevant portion of the flow alongside the rigs is influenced by this developing region. Detailed knowledge of the flow development and the resulting heat transfer coefficients is necessary to optimize the flow channel inlet design and to avoid

  11. Predictors of floater status in a long-lived bird: a cross-sectional and longitudinal test of hypotheses.

    Science.gov (United States)

    Sergio, Fabrizio; Blas, Julio; Hiraldo, Fernando

    2009-01-01

    1. Few studies have been capable of monitoring the nonterritorial sector of a population because of the typically secretive behaviour of floating individuals, despite the existing consensus over the demographic importance of floating. Furthermore, there is almost no information on floating behaviour for migratory species. 2. The factors that determine whether an individual will be a floater or a territory owner have been framed into five, non-mutually exclusive hypotheses: (i) territory holders are morphologically superior to floaters (resource-holding potential hypothesis); (ii) age confers skills and fighting motivation which lead to social dominance and territory ownership (age hypothesis); (iii) occupancy time of a site determines asymmetries in its knowledge, familiarity and value for potential contenders (site-dominance hypothesis); (iv) contenders use an arbitrary rule to settle contests leading to pre-defined cut-off points for a biologically meaningful trait (e.g. age, body size) separating floaters from territory holders (arbitrary convention hypothesis); and (v) floaters set up a 'war of attrition' at arbitrarily chosen territories (arbitrary attrition hypothesis). 3. We tested these hypotheses using long-term data on a long-lived, migratory raptor, the black kite Milvus migrans Boddaert. 4. Floating status was best explained by the concerted action of mechanisms consistent with the age and site-dominance hypotheses. 5. In both cross-sectional and longitudinal analyses, acquisition of a territory was determined by a complex interaction between age and early arrival from migration, suggesting: (i) a progressive incorporation of early arriving individuals in the territorial contingent of the population, and (ii) the existence of an alternative restraint strategy of delayed territoriality mediated by long-term acquisition of social dominance. 6. Such results suggested that territory acquisition was mediated by the establishment of site dominance through pre

  12. Actual Versus Perceived HIV Testing Norms, and Personal HIV Testing Uptake: A Cross-Sectional, Population-Based Study in Rural Uganda.

    Science.gov (United States)

    Perkins, Jessica M; Nyakato, Viola N; Kakuhikire, Bernard; Mbabazi, Pamela K; Perkins, H Wesley; Tsai, Alexander C; Subramanian, S V; Christakis, Nicholas A; Bangsberg, David R

    2018-02-01

    HIV testing is an essential part of treatment and prevention. Using population-based data from 1664 adults across eight villages in rural Uganda, we assessed individuals' perception of the norm for HIV testing uptake in their village and compared it to the actual uptake norm. In addition, we examined how perception of the norm was associated with personal testing while adjusting for other factors. Although the majority of people had been tested for HIV across all villages, slightly more than half of men and women erroneously thought that the majority in their village had never been tested. They underestimated the prevalence of HIV testing uptake by 42 percentage points (s.d. = 17 percentage points), on average. Among men, perceiving that HIV testing was not normative was associated with never testing for HIV (AOR = 2.6; 95% CI 1.7-4.0, p testing uptake.

  13. Isolation, incubation, and parallel functional testing and identification by FISH of rare microbial single-copy cells from multi-species mixtures using the combination of chemistrode and stochastic confinement.

    Science.gov (United States)

    Liu, Weishan; Kim, Hyun Jung; Lucchetta, Elena M; Du, Wenbin; Ismagilov, Rustem F

    2009-08-07

    This paper illustrates a plug-based microfluidic approach combining the technique of the chemistrode and the principle of stochastic confinement, which can be used to i) starting from a mixture of cells, stochastically isolate single cells into plugs, ii) incubate the plugs to grow clones of the individual cells without competition among different clones, iii) split the plugs into arrays of identical daughter plugs, where each plug contained clones of the original cell, and iv) analyze each array by an independent technique, including cellulase assays, cultivation, cryo-preservation, Gram staining, and Fluorescence In Situ Hybridization (FISH). Functionally, this approach is equivalent to simultaneously assaying the clonal daughter cells by multiple killing and non-killing methods. A new protocol for single-cell FISH, a killing method, was developed to identify isolated cells of Paenibacillus curdlanolyticus in one array of daughter plugs using a 16S rRNA probe, Pc196. At the same time, live copies of P. curdlanolyticus in another array were obtained for cultivation. Among technical advances, this paper reports a chemistrode that enables sampling of nanoliter volumes directly from environmental specimens, such as soil slurries. In addition, a method for analyzing plugs is described: an array of droplets is deposited on the surface, and individual plugs are injected into the droplets of the surface array to induce a reaction and enable microscopy without distortions associated with curvature of plugs. The overall approach is attractive for identifying rare, slow growing microorganisms and would complement current methods to cultivate unculturable microbes from environmental samples.

  14. Aerofractures in Confined Granular Media

    Science.gov (United States)

    Eriksen, Fredrik K.; Turkaya, Semih; Toussaint, Renaud; Måløy, Knut J.; Flekkøy, Eirik G.

    2015-04-01

    We will present the optical analysis of experimental aerofractures in confined granular media. The study of this generic process may have applications in industries involving hydraulic fracturing of tight rocks, safe construction of dams, tunnels and mines, and in earth science where phenomena such as mud volcanoes and sand injectites are results of subsurface sediment displacements driven by fluid overpressure. It is also interesting to increase the understanding the flow instability itself, and how the fluid flow impacts the solid surrounding fractures and in the rest of the sample. Such processes where previously studied numerically [Niebling 2012a, Niebling 2012b] or in circular geometries. We will here explore experimentally linear geometries. We study the fracturing patterns that form when air flows into a dense, non-cohesive porous medium confined in a Hele-Shaw cell - i.e. into a packing of dry 80 micron beads placed between two glass plates separated by ~1mm. The cell is rectangular and fitted with a semi-permeable boundary to the atmosphere - blocking beads but not air - on one short edge, while the other three edges are impermeable. The porous medium is packed inside the cell between the semi-permeable boundary and an empty volume at the sealed side where the air pressure can be set and kept at a constant overpressure (1-2bar). Thus, for the air trapped inside the cell to release the overpressure it has to move through the solid. At high enough overpressures the air flow deforms the solid and increase permeability in some regions along the air-solid interface, which results in unstable flow and aerofracturing. Aerofractures are thought to be an analogue to hydrofractures, and an advantage of performing aerofracturing experiments in a Hele-Shaw cell is that the fracturing process can easily be observed in the lab. Our experiments are recorded with a high speed camera with a framerate of 1000 frames per second. In the analysis, by using various image

  15. Parameters estimation of Drucker-Prager plasticity criteria for steel confined circular concrete columns in compression

    Directory of Open Access Journals (Sweden)

    Al-Kutti Walid A.

    2018-01-01

    Full Text Available This paper explores the possibility to use Drucker-Prager model in Steel-Concrete composite section. Numerical simulation was conducted using finite element package to simulate the steel-concrete composite section subjected to uniaxial compressive loading. After calibration with experimental study, parametric study was conducted to evaluate the effect of the friction angle and the cohesion constant c on the stress-strain curve of composite section. Empirical relationship between the friction angle and the confined concrete compressive strength was developed and a range of cohesion constant c between 5-10 MPa was suggested for confined concrete strength range of 25 to 100 MPa, respectively.

  16. High Strength Concrete Columns under Axial Compression Load: Hybrid Confinement Efficiency of High Strength Transverse Reinforcement and Steel Fibers

    Science.gov (United States)

    Perceka, Wisena; Liao, Wen-Cheng; Wang, Yo-de

    2016-01-01

    Addition of steel fibers to high strength concrete (HSC) improves its post-peak behavior and energy absorbing capability, which can be described well in term of toughness. This paper attempts to obtain both analytically and experimentally the efficiency of steel fibers in HSC columns with hybrid confinement of transverse reinforcement and steel fibers. Toughness ratio (TR) to quantify the confinement efficiency of HSC columns with hybrid confinement is proposed through a regression analysis by involving sixty-nine TRs of HSC without steel fibers and twenty-seven TRs of HSC with hybrid of transverse reinforcement and steel fibers. The proposed TR equation was further verified by compression tests of seventeen HSC columns conducted in this study, where twelve specimens were reinforced by high strength rebars in longitudinal and transverse directions. The results show that the efficiency of steel fibers in concrete depends on transverse reinforcement spacing, where the steel fibers are more effective if the spacing transverse reinforcement becomes larger in the range of 0.25–1 effective depth of the section column. Furthermore, the axial load–strain curves were developed by employing finite element software (OpenSees) for simulating the response of the structural system. Comparisons between numerical and experimental axial load–strain curves were carried out. PMID:28773391

  17. Generating equilateral random polygons in confinement

    International Nuclear Information System (INIS)

    Diao, Y; Ernst, C; Montemayor, A; Ziegler, U

    2011-01-01

    One challenging problem in biology is to understand the mechanism of DNA packing in a confined volume such as a cell. It is known that confined circular DNA is often knotted and hence the topology of the extracted (and relaxed) circular DNA can be used as a probe of the DNA packing mechanism. However, in order to properly estimate the topological properties of the confined circular DNA structures using mathematical models, it is necessary to generate large ensembles of simulated closed chains (i.e. polygons) of equal edge lengths that are confined in a volume such as a sphere of certain fixed radius. Finding efficient algorithms that properly sample the space of such confined equilateral random polygons is a difficult problem. In this paper, we propose a method that generates confined equilateral random polygons based on their probability distribution. This method requires the creation of a large database initially. However, once the database has been created, a confined equilateral random polygon of length n can be generated in linear time in terms of n. The errors introduced by the method can be controlled and reduced by the refinement of the database. Furthermore, our numerical simulations indicate that these errors are unbiased and tend to cancel each other in a long polygon. (paper)

  18. Recent results of H-mode confinement study in JT-60U (April-September, 1995)

    International Nuclear Information System (INIS)

    1995-11-01

    Improvement in the performance of energy confinement is one of the most important issues to realize thermonuclear fusion reactors. The H-mode is one of excellent improved confinement modes. From the view point of steady-state operation, the ELMy H-mode is considered to be a principal operation mode in ITER. For the engineering design of the ITER, there still remain issues to be clarified on the H-mode characteristics. These issues are required to be studied on the present tokamaks as ITER physics research needs. In order to satisfy the above request, experiments of the H-mode confinement have been carried out on JT-60U. Recent results of H-mode confinement study in JT-60U during April to September, 1995 are summarized in the present report. The scaling of high T i H-mode confinement is described in section 2. The time behaviour of transport properties are shown in sections 3 and 4. Result of the non-dimensional transport experiment is presented in section 5. The H-mode transition is investigated in sections 6, 7, 8 and 9; threshold power scaling, parametric study on edge local quantities, effect of edge neutrals, and H-L back transition. The onset condition of ELMs is studied in section 10. (author)

  19. Confinement and heating of a deuterium-tritium plasma

    Energy Technology Data Exchange (ETDEWEB)

    Hawryluk, R.J.; Adler, H.; Alling, P.; Ancher, C.; Anderson, H.; Anderson, J.L.; Ashcroft, D.; Barnes, C.W.; Barnes, G.; Batha, S.; Bell, M.G.; Bell, R.; Bitter, M.; Blanchard, W.; Bretz, N.L.; Budny, R.; Bush, C.E.; Camp, R.; Caorlin, M.; Cauffman, S.; Chang, Z.; Cheng, C.Z.; Collins, J.; Coward, G.; Darrow, D.S.; DeLooper, J.; Duong, H.; Dudek, L.; Durst, R.; Efthimion, P.C.; Ernst, D.; Fisher, R.; Fonck, R.J.; Fredrickson, E.; Fromm, N.; Fu, G.Y.; Furth, H.P.; Gentile, C.; Gorelenkov, N.; Grek, B.; Grisham, L.R.; Hammett, G.; Hanson, G.R.; Heidbrink, W.; Herrmann, H.W.; Hill, K.W.; Hosea, J.; Hsuan, H.; Janos, A.; Jassby, D.L.; Jobes, F.C.; Johnson, D.W.; Johnson, L.C.; Kamperschroer, J.; Kugel, H.; Lam, N.T.; LaMarche, P.H.; Loughlin, M.J.; LeBlanc, B.; Leonard, M.; Levinton, F.M.; Machuzak, J.; Mansfield, D.K.; Martin, A.; Mazzucato, E.; Majeski, R.; Marmar, E.; McChesney, J.; McCormack, B.; McCune, D.C.; McGuire, K.M.; McKee, G.; Meade, D.M.; Medley, S.S.; Mikkelsen, D.R.; Muelle

    1994-05-30

    The Tomamak Fusion Test reactor has performed initial high-power experiments with the plasma fueled with nominally equal densities of deuterium and tritium. Compared to pure deuterium plasmas, the energy stored in the electron and ions increased by [similar to]20%. These increases indicate improvements in confinement associated with the use of tritium and possibly heating of electrons by [alpha] particles created by the D-T fusion reactions.

  20. Plasma confinement in the TMX tandem mirror

    International Nuclear Information System (INIS)

    Hooper, E.B. Jr.; Allen, S.L.; Casper, T.A.

    1981-01-01

    Plasma confinement in the Tandem Mirror Experiment (TMX) is described. Axially confining potentials are shown to exist throughout the central 20-cm core of TMX. Axial electron-confinement time is up to 100 times that of single-cell mirror machines. Radial transport of ions is smaller than axial transport near the axis. It has two parts at large radii: nonambipolar, in rough agreement with predictions from resonant-neoclassical transport theory, and ambipolar, observed near the plasma edge under certain conditions, accompanied by a low-frequency, m = 1 instability or strong turbulence

  1. Numerical Investigations On The Seismic Behaviour Of Confined Masonry Walls

    International Nuclear Information System (INIS)

    Calderini, Chiara; Cattari, Serena; Lagomarsino, Sergio

    2008-01-01

    In the last century, severe earthquakes highlighted the seismic vulnerability of unreinforced masonry buildings. Many technological innovations have been introduced in time in order to improve resistance, ductility, and dissipation properties of this type of constructions. The most widely diffused are reinforced masonry and confined masonry. Damage observation of recent earthquakes demonstrated the effectiveness of the response of confined masonry structures to seismic actions. In general, in this type of structures, reinforced concrete beams and columns are not main structural elements, however, they have the following functions: to confine masonry in order to increase its ductility; to bear tensile stresses derived from bending; to contrast the out-of-plane overturning of masonry panels. It is well evident that these functions are as much effectively performed as the connection between masonry and reinforced concrete elements is good (for example by mean of local interlocking or reinforcements). Confined masonry structures have been extensively studied in the last decades both from a theoretical point of view and by experimental tests Aims of this paper is to give a contribution to the understanding of the seismic behaviour of confined masonry walls by means of numerical parametrical analyses. There latter are performed by mean of the finite element method; a nonlinear anisotropic constitutive law recently developed for masonry is adopted. Comparison with available experimental results are carried out in order to validate the results. A comparison between the resistance obtained from the numerical analyses and the prevision provided by simplified resistance criteria proposed in literature and in codes is finally provided

  2. Confinement Vessel Assay System: Design and Implementation Report

    Energy Technology Data Exchange (ETDEWEB)

    Frame, Katherine C. [Los Alamos National Laboratory; Bourne, Mark M. [Los Alamos National Laboratory; Crooks, William J. [Los Alamos National Laboratory; Evans, Louise [Los Alamos National Laboratory; Mayo, Douglas R. [Los Alamos National Laboratory; Gomez, Cipriano D. [Retired CMR-OPS: OPERATIONS; Miko, David K. [Los Alamos National Laboratory; Salazar, William R. [Los Alamos National Laboratory; Stange, Sy [Los Alamos National Laboratory; Vigil, Georgiana M. [Los Alamos National Laboratory

    2012-07-18

    Los Alamos National Laboratory has a number of spherical confinement vessels remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1- to 2-inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the vessels. We have developed a neutron assay system for the purposes of Materials Control and Accountability (MC&A) measurements of the vessel prior to and after cleanout. We present our approach to confronting the challenges in designing, building, and testing such a system. The system was designed to meet a set of functional and operational requirements. A Monte Carlo model was developed to aid in optimizing the detector design as well as to predict the systematic uncertainty associated with confinement vessel measurements. Initial testing was performed to optimize and determine various measurement parameters, and then the system was characterized using {sup 252}Cf placed a various locations throughout the measurement system. Measurements were also performed with a {sup 252}Cf source placed inside of small steel and HDPE shells to study the effect of moderation. These measurements compare favorably with their MCNPX model equivalent, making us confident that we can rely on the Monte Carlo simulation to predict the systematic uncertainty due to variations in response to material that may be localized at different points within a vessel.

  3. iPhone Sensors in Tracking Outcome Variables of the 30-Second Chair Stand Test and Stair Climb Test to Evaluate Disability: Cross-Sectional Pilot Study.

    Science.gov (United States)

    Adusumilli, Gautam; Joseph, Solomon Eben; Samaan, Michael A; Schultz, Brooke; Popovic, Tijana; Souza, Richard B; Majumdar, Sharmila

    2017-10-27

    Performance tests are important to characterize patient disabilities and functional changes. The Osteoarthritis Research Society International and others recommend the 30-second Chair Stand Test and Stair Climb Test, among others, as core tests that capture two distinct types of disability during activities of daily living. However, these two tests are limited by current protocols of testing in clinics. There is a need for an alternative that allows remote testing of functional capabilities during these tests in the osteoarthritis patient population. Objectives are to (1) develop an app for testing the functionality of an iPhone's accelerometer and gravity sensor and (2) conduct a pilot study objectively evaluating the criterion validity and test-retest reliability of outcome variables obtained from these sensors during the 30-second Chair Stand Test and Stair Climb Test. An iOS app was developed with data collection capabilities from the built-in iPhone accelerometer and gravity sensor tools and linked to Google Firebase. A total of 24 subjects performed the 30-second Chair Stand Test with an iPhone accelerometer collecting data and an external rater manually counting sit-to-stand repetitions. A total of 21 subjects performed the Stair Climb Test with an iPhone gravity sensor turned on and an external rater timing the duration of the test on a stopwatch. App data from Firebase were converted into graphical data and exported into MATLAB for data filtering. Multiple iterations of a data processing algorithm were used to increase robustness and accuracy. MATLAB-generated outcome variables were compared to the manually determined outcome variables of each test. Pearson's correlation coefficients (PCCs), Bland-Altman plots, intraclass correlation coefficients (ICCs), standard errors of measurement, and repeatability coefficients were generated to evaluate criterion validity, agreement, and test-retest reliability of iPhone sensor data against gold-standard manual

  4. FINAL DESIGN REVIEW REPORT Subcritical Experiments Gen 2, 3-ft Confinement Vessel Weldment

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Christopher [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-28

    A Final Design Review (FDR) of the Subcritical Experiments (SCE) Gen 2, 3-ft. Confinement Vessel Weldment was held at Los Alamos National Laboratory (LANL) on September 14, 2017. The review was a focused review on changes only to the confinement vessel weldment (versus a system design review). The changes resulted from lessons-learned in fabricating and inspecting the current set of confinement vessels used for the SCE Program. The baseline 3-ft. confinement vessel weldment design has successfully been used (to date) for three (3) high explosive (HE) over-tests, two (2) fragment tests, and five (5) integral HE experiments. The design team applied lessons learned from fabrication and inspection of these vessel weldments to enhance fit-up, weldability, inspection, and fitness for service evaluations. The review team consisted of five (5) independent subject matter experts with engineering design, analysis, testing, fabrication, and inspection experience. The

  5. Use of point-of-care tests among general practitioners: a cross-sectional study in Saxony, Germany.

    Science.gov (United States)

    Frese, Thomas; Steger, Kathleen; Deutsch, Tobias; Schmid, Gordian L; Sandholzer, Hagen

    2016-01-01

    There is little knowledge about the use of point-of-care (POC) tests among general practitioners (GPs). The aim of this study was to determine which POC tests are known and used by GPs and how they estimate the usefulness of those tests. The use of POC tests among GPs and university-associated general practitioners who teach undergraduates (GPTUs) was elucidated. Differences between GPs working in urban and rural areas were also investigated. The knowledge, utilisation and usefulness (as estimated by the responders) of 27 POC tests were assessed with a self-designed questionnaire in a random sample of GPs (n=244) and GPTUs (n=48) in Saxony, Germany. A total of 63 GPs and 31 GPTUs (response rates 26.5% and 64.6%, respectively) responded. No relevant difference between GPs and GPTUs was found. The GPs were familiar with 22.5±4.5 (mean ± standard deviation) of the laboratory parameters, the GPTUs with 22.9±4.3 (p=0.427). The amount of recognised POC tests was 11.6±4.9 vs 12.4±5.5 (GPs vs GPTUs; p=0.441). The amount of utilised POC tests was 5.5±2.3 vs 6.0±2.5 (GPs vs GPTUs; p=0.431). Rural GPs were familiar with more POC tests than urban GPs (mean number of tests (rural vs urban): 13.3±5.5 vs 10.6±4.4; p=0.011), but there was no difference in the amount of utilised POC tests. Twelve of the 27 POC tests were estimated as useful by more than 50% of the responders who answered this item. Only a limited number of rapid tests are estimated as useful and are used by GPs in Saxony.

  6. Propagating confined states in phase dynamics

    International Nuclear Information System (INIS)

    Brand, H.R.; Deissler, R.J.

    1992-01-01

    We show that the nonlinear phase equation that applies to propagating patterns allows for a large range of parameter values for propagating confined states for which a spatially localized region with wavelengths different from that of the background travels on this background. This phenomenon is the generalization of the stationary confined states predicted a few years ago by the authors, which have since been seen experimentally in various systems. We suggest that the propagating confined states found here could arise in spirals in Taylor vortex flow or in convective systems showing traveling waves far above onset. We find that the propagating confined states can be replaced by a pattern that is irregular in space and time as the control parameter in the nonlinear phase equation is varied

  7. The Physics Basis of ITER Confinement

    International Nuclear Information System (INIS)

    Wagner, F.

    2009-01-01

    ITER will be the first fusion reactor and the 50 year old dream of fusion scientists will become reality. The quality of magnetic confinement will decide about the success of ITER, directly in the form of the confinement time and indirectly because it decides about the plasma parameters and the fluxes, which cross the separatrix and have to be handled externally by technical means. This lecture portrays some of the basic principles which govern plasma confinement, uses dimensionless scaling to set the limits for the predictions for ITER, an approach which also shows the limitations of the predictions, and describes briefly the major characteristics and physics behind the H-mode--the preferred confinement regime of ITER.

  8. Reorientational dynamics of water confined in zeolites.

    Science.gov (United States)

    Fogarty, Aoife C; Coudert, François-Xavier; Boutin, Anne; Laage, Damien

    2014-02-24

    We present a detailed molecular-dynamics study of water reorientation and hydrogen-bond dynamics in a strong confinement situation, within the narrow pores of an all-silica Linde type A (LTA) zeolite. Two water loadings of the zeolite are compared with the bulk case. Water dynamics are retarded in this extreme hydrophobic confinement and the slowdown is more pronounced at higher water loading. We show that water reorientation proceeds mainly by large-amplitude angular jumps, whose mechanism is similar to that determined in the bulk. The slowdown upon hydrophobic confinement arises predominantly from an excluded-volume effect on the large fraction of water molecules lying at the interface with the zeolite matrix, with an additional minor contribution coming from a structuring effect induced by the confinement. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Eros-based Confined Capability Client

    National Research Council Canada - National Science Library

    Shapiro, Jonathan S

    2006-01-01

    Objective of EROS-Based Confined Capability Client Project is to demonstrate that systems constructed using capability-based protection can be organized in a way that makes it defensible from hostile internet content...

  10. Vorticity confinement technique for drag prediction

    Science.gov (United States)

    Povitsky, Alex; Snyder, Troy

    2011-11-01

    This work couples wake-integral drag prediction and vorticity confinement technique (VC) for the improved prediction of drag from CFD simulations. Induced drag computations of a thin wing are shown to be more accurate than the more widespread method of surface pressure integration when compared to theoretical lifting-line value. Furthermore, the VC method improves trailing vortex preservation and counteracts the shift from induced drag to numerical entropy drag with increasing distance of Trefftz plane downstream of the wing. Accurate induced drag prediction via the surface integration of pressure barring a sufficiently refined surface grid and increased computation time. Furthermore, the alternative wake-integral technique for drag prediction suffers from numerical dissipation. VC is shown to control the numerical dissipation with very modest computational overhead. The 2-D research code is used to test specific formulations of the VC body force terms and illustrate the computational efficiency of the method compared to a ``brute force'' reduction in spatial step size. For the 3-D wing simulation, ANSYS FLUENT is employed with the VC body force terms added to the solver with user-defined functions (UDFs). VC is successfully implemented to highly unsteady flows typical for Micro Air Vehicles (MAV) producing oscillative drag force either by natural vortex shedding at high angles of attack or by flapping wing motion.

  11. Effect of new cross-section evaluations on criticality and neutron energy spectrum of a typical material test research reactor

    International Nuclear Information System (INIS)

    Ahmad, Siraj-ul-Islam; Ahmad, Nasir; Aslam

    2004-01-01

    Several new WIMSD libraries based on recent cross-section evaluations such as IAEA, ENDFB-VI, JENDL, and JEF have been made available by IAEA. These libraries were used for the computation of multiplication factor and energy spectrum for Pakistan Research Reactor-1 (PARR-1). Methodology was validated for benchmark problems made available by IAEA and comparison with reference results. The value of effective multiplication factors for all newly released libraries are 1.8-3.2% less than that of 1981 WIMSD library. The effect of various cross-section libraries on neutron energy spectrum was also studied. Differences of about -10% to 12.5% were found in thermal flux using the newly released libraries as compared with that obtained using 1981 WIMSD library. From the analysis, it was found that the main source of the difference is the cross-sections of hydrogen bound in water. When these cross-sections of hydrogen (bound in water) from new libraries were used along with all other data in 1981 WIMSD library, the k eff obtained in this way has a difference of only 0.02-0.8% with that obtained from new libraries, while the flux spectrum agreed within 1% below 1 MeV with new libraries

  12. Magnetic confinement in plasmas in nuclear devices

    International Nuclear Information System (INIS)

    Tull, C.G.

    1979-01-01

    The main emphasis of the magnetic fusion energy research program today lies in the development of two types of confinement schemes: magnetic mirrors and tokamaks. Experimental programs for both of these confinement schemes have shown steady progress toward achieving fusion power breakeven. The scaling of the current machines to a reactor operating regime and newly developed methods for plasma heating will very likely produce power breakeven within the next decade. Predictions are that the efficiency in a fusion power plant should exceed 32%

  13. Stellarator approach to toroidal plasma confinement

    International Nuclear Information System (INIS)

    Johnson, J.L.

    1981-12-01

    An overview is presented of the development and current status of the stellarator approach to controlled thermonuclear confinement. Recent experimental, theoretical, and systems developments have made this concept a viable option for the evolution of the toroidal confinement program. Some experimental study of specific problems associated with departure from two-dimensional symmetry must be undertaken before the full advantages and opportunities of steady-state, net-current-free operation can be realized

  14. Relationship between lung function and Modified Shuttle Test performance in adult patients with cystic fibrosis : A cross-sectional, retrospective study

    NARCIS (Netherlands)

    Doeleman, W. R.; Takken, T.; Bronsveld, I.; Hulzebos, E. H J

    2016-01-01

    Objectives: To investigate the relationship between lung function and exercise capacity in adults with cystic fibrosis (CF), and to develop a CF-specific equation to predict Modified Shuttle Test (MST) performance from baseline data. Design: Cross-sectional, retrospective study. Setting: Adult CF

  15. Triaging borderline/mild dyskaryotic Pap cytology with p16/Ki-67 dual-stained cytology testing: Cross-sectional and longitudinal outcome study

    NARCIS (Netherlands)

    M.H. Uijterwaal (Margot); B.I. Witte (Birgit); F.J. van Kemenade (Folkert); D.C. Rijkaart (Dorien); R. de Ridder (Rogier); J. Berkhof (Johannes); G.A.M.A. Balfoort-Van Der Meij (G. A M A); M.C.G. Bleeker; P.J.F. Snijders (Peter); C.J.L.M. Meijer (Chris J. L.)

    2014-01-01

    textabstractBackground: Women with borderline/mildly dyskaryotic (BMD) cytology smears are currently followed up with repeat testing at 6 and 18 months. The objective of this study is to analyse the cross-sectional and longitudinal performance of p16/Ki-67 dual-stained cytology for the detection of

  16. The decay of confined vortex rings

    Science.gov (United States)

    Stewart, K. C.; Niebel, C. L.; Jung, S.; Vlachos, P. P.

    2012-07-01

    Vortex rings are produced during the ejection of fluid through a nozzle or orifice, which occurs in a wide range of biological conditions such as blood flow through the valves of the heart or through arterial constrictions. Confined vortex ring dynamics, such as these, have not been previously studied despite their occurrence within the biological flow conditions mentioned. In this work, we investigate laminar vortex rings using particle image velocimetry and develop a new semi-empirical model for the evolution of vortex ring circulation subject to confinement. Here we introduce a decay parameter β which exponentially grows with increasing vortex ring confinement ratio, the ratio of the vortex ring diameter ( D VR) to the confinement diameter ( D), with the relationship β=4.38 exp(9.5D_VR/D), resulting in a corresponding increase in the rate of vortex ring circulation decay. This work enables the prediction of circulation decay rate based on confinement, which is important to understanding naturally occurring confined vortex ring dynamics.

  17. ENDF/B-VII.1 Neutron Cross Section Data Testing with Critical Assembly Benchmarks and Reactor Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kahler, A.C.; Herman, M.; Kahler,A.C.; MacFarlane,R.E.; Mosteller,R.D.; Kiedrowski,B.C.; Frankle,S.C.; Chadwick,M.B.; McKnight,R.D.; Lell,R.M.; Palmiotti,G.; Hiruta,H.; Herman,M.; Arcilla,R.; Mughabghab,S.F.; Sublet,J.C.; Trkov,A.; Trumbull,T.H.; Dunn,M.

    2011-12-01

    The ENDF/B-VII.1 library is the latest revision to the United States Evaluated Nuclear Data File (ENDF). The ENDF library is currently in its seventh generation, with ENDF/B-VII.0 being released in 2006. This revision expands upon that library, including the addition of new evaluated files (was 393 neutron files previously, now 423 including replacement of elemental vanadium and zinc evaluations with isotopic evaluations) and extension or updating of many existing neutron data files. Complete details are provided in the companion paper [M. B. Chadwick et al., 'ENDF/B-VII.1 Nuclear Data for Science and Technology: Cross Sections, Covariances, Fission Product Yields and Decay Data,' Nuclear Data Sheets, 112, 2887 (2011)]. This paper focuses on how accurately application libraries may be expected to perform in criticality calculations with these data. Continuous energy cross section libraries, suitable for use with the MCNP Monte Carlo transport code, have been generated and applied to a suite of nearly one thousand critical benchmark assemblies defined in the International Criticality Safety Benchmark Evaluation Project's International Handbook of Evaluated Criticality Safety Benchmark Experiments. This suite covers uranium and plutonium fuel systems in a variety of forms such as metallic, oxide or solution, and under a variety of spectral conditions, including unmoderated (i.e., bare), metal reflected and water or other light element reflected. Assembly eigenvalues that were accurately predicted with ENDF/B-VII.0 cross sections such as unmoderated and uranium reflected {sup 235}U and {sup 239}Pu assemblies, HEU solution systems and LEU oxide lattice systems that mimic commercial PWR configurations continue to be accurately calculated with ENDF/B-VII.1 cross sections, and deficiencies in predicted eigenvalues for assemblies containing selected materials, including titanium, manganese, cadmium and tungsten are greatly reduced. Improvements are also

  18. Conference summary: Experiments in confinement and plasma-wall interaction and innovative confinement concept

    International Nuclear Information System (INIS)

    Ninomiya, H.

    2005-01-01

    This paper summarizes the results presented at the 20th IAEA Fusion Energy Conference 2004 in the sessions of confinement, plasma-wall interaction and innovative confinement concept. The highlights of the presentations are as follows. Long pulse operation with high beta and high bootstrap fraction much longer than the current diffusion time has been achieved. The discharge scenario optimization and its extrapolation towards ITER have progressed remarkably. Significant progress has been made in understanding of global confinement and transport physics. (author)

  19. Experimental Study on Fibre-reinforced Cementitious Matrix Confined Concrete Columns under Axial Compression

    Directory of Open Access Journals (Sweden)

    Lan Zeng

    2017-03-01

    Full Text Available Poor fire resistance of fibre-reinforced polymer (FRP restricts its further application in construction structures. In this paper, a novel fibre-reinforced cementitious matrix confined concrete column (FRCMCC using fireproof grout as the fibre matrix was developed, and experiments were conducted to establish its performance and analyse the mechanical properties under axial compression. The test results show that its failure mode was more moderate compared to the traditional fibre-reinforced resinous matrix confined concrete column (FRRMCC, and the concrete columns confined with multi-layer fibres and end reinforcement could provide both good strength and ductility.

  20. Confinement Vessel Assay System: Calibration and Certification Report

    Energy Technology Data Exchange (ETDEWEB)

    Frame, Katherine C. [Los Alamos National Laboratory; Bourne, Mark M. [Los Alamos National Laboratory; Crooks, William J. [Los Alamos National Laboratory; Evans, Louise [Los Alamos National Laboratory; Gomez, Cipriano [Retired CMR-OPS: OPERATIONS; Mayo, Douglas R. [Los Alamos National Laboratory; Miko, David K. [Los Alamos National Laboratory; Salazar, William R. [Los Alamos National Laboratory; Stange, Sy [Los Alamos National Laboratory; Vigil, Georgiana M. [Los Alamos National Laboratory

    2012-07-17

    Los Alamos National Laboratory has a number of spherical confinement vessels (CVs) remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1 to 2 inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the vessels. The Confinement Vessel Assay System (CVAS) was developed to measure the amount of SNM in CVs before and after cleanout. Prior to cleanout, the system will be used to perform a verification measurement of each vessel. After cleanout, the system will be used to perform safeguards-quality assays of {le} 100-g {sup 239}Pu equivalent in a vessel for safeguards termination. The system was calibrated in three different mass regions (low, medium, and high) to cover the entire plutonium mass range that will be assayed. The low mass calibration and medium mass calibration were verified for material positioned in the center of an empty vessel. The systematic uncertainty due to position bias was estimated using an MCNPX model to simulate the response of the system to material localized at various points along the inner surface of the vessel. The background component due to cosmic ray spallation was determined by performing measurements of an empty vessel and comparing to measurements in the same location with no vessel present. The CVAS has been tested and calibrated in preparation for verification and safeguards measurements of CVs before and after cleanout.

  1. Experimental investigation of cooling by top spray and bottom flooding of a simulated 64 rod bundle for a BWR. Pt. 2. Main experiment with modified test section

    International Nuclear Information System (INIS)

    Nilsson, L.; Gustafson, L.; Harju, R.

    1978-06-01

    The cooling of an electrically heated, full scale 64-rod bundle has been investigated under simulated emergency core cooling conditions. Emphasis was laid on measurements of rod cladding and canister temperatures. By means of difference pressure measurements the levels in bundle, by-pass and downcomer could be estimated and thus the effective reflooding velocity. The test section was modified compared to the pre-tests, in order to improve system effects simulation. A new rod bundle was installed including a hollow, water, rod and 63 indirectly heated rods. Parameter effects of coolant mass flow rate and distribution, initial cladding temperature, pressure and power were studied. The effect of the way the test section was vented was also investigated and turned out to be very significant. (author)

  2. Topology of polymer chains under nanoscale confinement.

    Science.gov (United States)

    Satarifard, Vahid; Heidari, Maziar; Mashaghi, Samaneh; Tans, Sander J; Ejtehadi, Mohammad Reza; Mashaghi, Alireza

    2017-08-24

    Spatial confinement limits the conformational space accessible to biomolecules but the implications for bimolecular topology are not yet known. Folded linear biopolymers can be seen as molecular circuits formed by intramolecular contacts. The pairwise arrangement of intra-chain contacts can be categorized as parallel, series or cross, and has been identified as a topological property. Using molecular dynamics simulations, we determine the contact order distributions and topological circuits of short semi-flexible linear and ring polymer chains with a persistence length of l p under a spherical confinement of radius R c . At low values of l p /R c , the entropy of the linear chain leads to the formation of independent contacts along the chain and accordingly, increases the fraction of series topology with respect to other topologies. However, at high l p /R c , the fraction of cross and parallel topologies are enhanced in the chain topological circuits with cross becoming predominant. At an intermediate confining regime, we identify a critical value of l p /R c , at which all topological states have equal probability. Confinement thus equalizes the probability of more complex cross and parallel topologies to the level of the more simple, non-cooperative series topology. Moreover, our topology analysis reveals distinct behaviours for ring- and linear polymers under weak confinement; however, we find no difference between ring- and linear polymers under strong confinement. Under weak confinement, ring polymers adopt parallel and series topologies with equal likelihood, while linear polymers show a higher tendency for series arrangement. The radial distribution analysis of the topology reveals a non-uniform effect of confinement on the topology of polymer chains, thereby imposing more pronounced effects on the core region than on the confinement surface. Additionally, our results reveal that over a wide range of confining radii, loops arranged in parallel and cross

  3. ENDF/B-VII.1 Neutron Cross Section Data Testing with Critical Assembly Benchmarks and Reactor Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kahler, A. [Los Alamos National Laboratory (LANL); Macfarlane, R E [Los Alamos National Laboratory (LANL); Mosteller, R D [Los Alamos National Laboratory (LANL); Kiedrowski, B C [Los Alamos National Laboratory (LANL); Frankle, S C [Los Alamos National Laboratory (LANL); Chadwick, M. B. [Los Alamos National Laboratory (LANL); Mcknight, R D [Argonne National Laboratory (ANL); Lell, R M [Argonne National Laboratory (ANL); Palmiotti, G [Idaho National Laboratory (INL); Hiruta, h [Idaho National Laboratory (INL); Herman, Micheal W [Brookhaven National Laboratory (BNL); Arcilla, r [Brookhaven National Laboratory (BNL); Mughabghab, S F [Brookhaven National Laboratory (BNL); Sublet, J C [Culham Science Center, Abington, UK; Trkov, A. [Jozef Stefan Institute, Slovenia; Trumbull, T H [Knolls Atomic Power Laboratory; Dunn, Michael E [ORNL

    2011-01-01

    The ENDF/B-VII.1 library is the latest revision to the United States' Evaluated Nuclear Data File (ENDF). The ENDF library is currently in its seventh generation, with ENDF/B-VII.0 being released in 2006. This revision expands upon that library, including the addition of new evaluated files (was 393 neutron files previously, now 423 including replacement of elemental vanadium and zinc evaluations with isotopic evaluations) and extension or updating of many existing neutron data files. Complete details are provided in the companion paper [1]. This paper focuses on how accurately application libraries may be expected to perform in criticality calculations with these data. Continuous energy cross section libraries, suitable for use with the MCNP Monte Carlo transport code, have been generated and applied to a suite of nearly one thousand critical benchmark assemblies defined in the International Criticality Safety Benchmark Evaluation Project's International Handbook of Evaluated Criticality Safety Benchmark Experiments. This suite covers uranium and plutonium fuel systems in a variety of forms such as metallic, oxide or solution, and under a variety of spectral conditions, including unmoderated (i.e., bare), metal reflected and water or other light element reflected. Assembly eigenvalues that were accurately predicted with ENDF/B-VII.0 cross sections such as unrnoderated and uranium reflected (235)U and (239)Pu assemblies, HEU solution systems and LEU oxide lattice systems that mimic commercial PWR configurations continue to be accurately calculated with ENDF/B-VII.1 cross sections, and deficiencies in predicted eigenvalues for assemblies containing selected materials, including titanium, manganese, cadmium and tungsten are greatly reduced. Improvements are also confirmed for selected actinide reaction rates such as (236)U; (238,242)Pu and (241,243)Am capture in fast systems. Other deficiencies, such as the overprediction of Pu solution system critical

  4. Longitudinal Acceleration Test of Overhead Luggage Bins and Auxiliary Fuel Tank in a Transport Airplane Airframe Section, Part 2

    National Research Council Canada - National Science Library

    McGuire, Robert

    2000-01-01

    ...). The purpose of the tests was to measure the structural responses and interaction between the fuselage, overhead stowage bins, and auxiliary fuel tank under simulated, potentially survivable, crash conditions...

  5. Longitudinal Acceleration Tests of Overhead Luggage Bins and Auxiliary Fuel Tank in a Transport Airplane Airframe Section

    National Research Council Canada - National Science Library

    McGuire, Robert

    1999-01-01

    ...). The purpose of the tests was to measure the structural responses and interaction between the fuselage, overhead stowage bins, and auxiliary fuel tank under simulated, potentially survivable, crash conditions...

  6. Semiquantitative fecal calprotectin test in postinfectious and non-postinfectious irritable bowel syndrome: cross-sectional study

    OpenAIRE

    David, Liliana-Elisabeta; Surdea-Blaga, Teodora; Dumitrascu, Dan-Lucian

    2014-01-01

    CONTEXT AND OBJECTIVE:The presence of a certain degree of inflammation in the gut wall is now accepted in irritable bowel syndrome (IBS). Fecal calprotectin is considered to be a reliable test for detecting intestinal inflammation. Our aim was to assess the presence of inflammation in postinfectious IBS (PI-IBS), compared with non-postinfectious IBS (NPI-IBS). A secondary objective was to determine the usefulness of a rapid fecal calprotectin test in inflammatory bowel diseases (IBD).DESIGN A...

  7. A score test for comparing cross-sectional survival data with a fraction of non-susceptible patients and its application in clinical immunology.

    Directory of Open Access Journals (Sweden)

    Sarah Flora Jonas

    Full Text Available In cross-sectional studies of time-to-event data collected by patient examinations at a single random point in time, a fraction of them will not experience the event regardless of the length of the follow-up time. This is the case in clinical immunology studies that include a mixed population, with both immune-reactive and immune-tolerant (or non-susceptible patients. In these cases, classical tests of current status data may perform poorly. New methods for testing these data are needed.In the two-sample comparison setting, we propose a score test for testing the null hypothesis that survival does not differ in either the non-susceptible fraction or the time-to-event distribution among the susceptible fraction.In a wide range of scenarios, simulation results show interesting improvements in power for the proposed score test compared to the logrank-type test in most of the configurations we investigated. In a cross-sectional study of drug immunogenicity among treated multiple sclerosis patients, the proposed score test reveals that gender is associated with the immunogenicity of interferon.

  8. Three-dimensional nonlinear waves under spatial confinement

    OpenAIRE

    Azhand, Arash

    2016-01-01

    The aim of my thesis is to study the evolution of scroll waves under spatial confinement both experimentally as well as numerically. Scroll waves represent three-dimensional (3D) analogs of spiral waves. In the simplest case, the central axis around which a scroll wave rotates is a straight line. The line is named the filament of the scroll wave, and each infinitesimal cross-section represents the core of a spiral wave. Two specific types of scroll waves are considered: (1) Straight scroll wa...

  9. Community views about routine HIV testing and antiretroviral treatment in Botswana: signs of progress from a cross sectional study

    Directory of Open Access Journals (Sweden)

    Mokoena Thamie

    2007-06-01

    Full Text Available Abstract Background The Botswana government began providing free antiretroviral therapy (ART in 2002 and in 2004 introduced routine HIV testing (RHT in government health facilities, aiming to increase HIV testing and uptake of ART. There have been concerns that the RHT programme might be coercive, lead to increased partner violence, and drive people away from government health services. Methods We conducted a household survey of 1536 people in a stratified random sample of communities across Botswana, asking about use and experience of government health services, views about RHT, views about ART, and testing for HIV in the last 12 months. Focus groups further discussed issues about ART. Results Some 81% of respondents had visited a government clinic within the last 24 months. Of these 92% were satisfied with the service, 96% felt they were treated with respect and 90% were comfortable about confidentiality. Almost all respondents said they would choose a government clinic for treatment of AIDS. Nearly one half (47% thought they were at risk of HIV. Those who had experienced partner violence within the last 12 months were more likely to think themselves at risk. One half of those who had visited a government facility in the last 24 months were offered HIV tests, and nearly half were tested. A few (8% of those who were not asked thought they were tested. Most people (79% had heard of RHT and 94% were in favour of it. Over one half (55% of the entire sample had been tested for HIV within the last 12 months, one half of these through RHT. Women were more likely to have been tested. Nearly everyone (94% had heard of ART and thought it could help AIDS. Focus groups identified problems of access to ART due to distance from treatment centres and long queues in the centres. Conclusion Public awareness and approval of RHT was very high. The high rate of RHT has contributed to the overall high rate of HIV testing. The government's programme to increase HIV

  10. Associations of the stair climb power test with muscle strength and functional performance in people with COPD: A cross-sectional study

    DEFF Research Database (Denmark)

    Roig, Marc; Eng, Janice J.; MacIntyre, Donna L.

    2010-01-01

    BACKGROUND: The Stair Climb Power Test (SCPT) is a functional test associated with leg muscle power in older people. OBJECTIVE: The purposes of this study were to compare the results of the SCPT in people with chronic obstructive pulmonary disease (COPD) and people who were healthy and to explore...... associations of the SCPT with muscle strength (force-generating capacity) and functional performance. DESIGN: The study was a cross-sectional investigation. METHODS: Twenty-one people with COPD and a predicted mean (SD) percentage of forced expiratory volume in 1 second of 47.2 (12.9) and 21 people who were...... healthy and matched for age, sex, and body mass were tested with the SCPT. Knee extensor and flexor muscle torque was assessed with an isokinetic dynamometer. Functional performance was assessed with the Timed "Up & Go" Test (TUG) and the Six-Minute Walk Test (6MWT). RESULTS: People with COPD showed lower...

  11. Assessment of global stellarator confinement: Status of the international stellarator confinement scaling data base

    International Nuclear Information System (INIS)

    Dinklage, A.; Beidler, C.D.; Dose, V.; Geiger, J.; Kus, A.; Preuss, R.; Ascasibar, E.; Tribaldos, V.; Harris, J.H.; Murakami, S.; Sano, F.; Okamura, S.; Suzuki, Y.; Watanabe, K.Y.; Yamada, H.; Yokoyama, M.; Stroth, U.; Talmadge, J.

    2005-01-01

    Different stellarator/heliotron devices along with their respective flexibility cover a large magnetic configuration space. Since the ultimate goal of stellarator research aims at an alternative fusion reactor concept, the exploration of the most promising configurations requires a comparative assessment of the plasma performance and how different aspects of a 3D configuration influence it. Therefore, the International Stellarator Confinement Database (ISCDB) has been re- initiated in 2004 and the ISS95 database has been extended to roughly 3000 discharges from eight different devices. Further data-sets are continuously added. A revision of a data set restricted to comparable scenarios lead to the ISS04 scaling law which confirmed ISS95 but also revealed clearly the necessity to incorporate configuration descriptive parameters. In other words, an extension beyond the set of regression parameters used for ISS95/ISS04 appears to be necessary and candidates, such as the elongation are investigated. Since grouping of data is a key-issue for deriving ISS04, basic assumptions are revised, e.g. the dependence on the heating scheme. Moreover, an assessment of statistical approaches is investigated with respect to their impact on the scaling. A crucial issue is the weighting of data groups which is discussed in terms of error-in-variable techniques and Bayesian model comparison. The latter is employed for testing scaling ansatzes depending on scaling invariance principles hence allowing the assessment of applicability of theory-based scaling laws on stellarator confinement. 1. ISCDB resources are jointly hosted by NIFS and IPP, see http://iscdb.nifs.ac.jp and http://www.ipp.mpg.de/ISS. (author)

  12. Behavior of circular footing resting on laterally confined granular reinforced soil

    OpenAIRE

    Elsaied, Ahmed Elzoghby; Saleh, Nasser Mosleh; Elmashad, Mohi Eldeen

    2015-01-01

    Three dimensional physical laboratory models were examined to investigate the influence of soil confinement on circular footing behavior resting on granular soil. A total of 23 model footing tests were performed. Nine hollow cylinders with various heights and diameters were installed around the footing model for soil confinement purpose. Square geogrid layers were placed at different depths beneath the bottom edge of the cylinder. Different parameters such as height, diameter, and depth of th...

  13. Monte Carlo testing of new cross section data sets for thermal and intermediate highly enriched uranium critical assemblies

    International Nuclear Information System (INIS)

    Weinman, J.P.

    1998-06-01

    The purpose of this study is to investigate the eigenvalue sensitivity to new 235 U, hydrogen, and oxygen cross section data sets by comparing RACER Monte Carlo calculations for several thermal and intermediate spectrum critical experiments. The new 235 U library (Version 107) was derived by L. Leal and H. Derrien by fitting differential experimental data for 235 U while constraining the fit to match experimental capture and fission resonance integrals and Maxwellian averaged thermal K1 (v fission minus absorption). The new hydrogen library (Version 45) consists of the ENDF/B-VI release 3 data with a 332.0 mb 2,200 m/s cross section which replaces the value of 332.6 mb in the current library. The new oxygen library (Version 39) is based on a recent evaluation of 16 O by E. Caro. Nineteen Oak Ridge and Rocky Flats thermal solution benchmark critical assemblies that span a range of hydrogen-to- 235 U (H/U) concentrations (2,052 to 27.1) and above-thermal neutron leakage fractions (0.555 to 0.011) were analyzed. In addition, three intermediate spectrum critical assemblies (UH3-UR, UH3-NI, and HISS-HUG) were studied

  14. International Stellarator/Heliotron Database progress on high-beta confinement and operational boundaries

    International Nuclear Information System (INIS)

    Weller, A.; Dinklage, A.; Geiger, J.; Preuss, R.; Werner, A.; Watanabe, K.Y.; Sakakibara, S.; Funaba, H.; Ohdachi, S.; Suzuki, Y.; Yamada, H.; Harris, J.H.; Zarnstorff, M.C.

    2009-01-01

    The International Stellarator/Heliotron Confinement Database was extended by high-β data compiled from the Large Helical System (LHD) and the W7-AS Stellarator. The main purpose is to enhance the basis for extrapolation of the global confinement properties to the reactor regime. The high-β configurations and experimental achievements in both devices are briefly described. The impact of beta on the configuration parameters and the global confinement is discussed. In particular, the confinement data in the high-β regime are compared with the ISS95 and ISS04 scaling laws which were derived from a database including relatively few high-β cases. In addition, a Bayesian model comparison approach is used to test scaling predictions derived from basic confinement models. Unlike in tokamaks, the operational boundaries in stellarators and helical systems are determined by the available heating power and confinement properties rather than by disruptive stability or density limits. The role of a pressure induced equilibrium limit is discussed in particular. An attempt is made to compare the high-β data with tokamak confinement and with operational boundaries observed in tokamaks. Further extensions of the database by parameters characterizing stability and local transport properties are proposed.

  15. Comparing the cyclic behavior of concrete cylinders confined by shape memory alloy wire or steel jackets

    International Nuclear Information System (INIS)

    Park, Joonam; Choi, Eunsoo; Kim, Hong-Taek; Park, Kyoungsoo

    2011-01-01

    Shape memory alloy (SMA) wire jackets for concrete are distinct from conventional jackets of steel or fiber reinforced polymer (FRP) since they provide active confinement which can be easily achieved due to the shape memory effect of SMAs. This study uses NiTiNb SMA wires of 1.0 mm diameter to confine concrete cylinders with the dimensions of 300 mm × 150 mm (L × D). The NiTiNb SMAs have a relatively wider temperature hysteresis than NiTi SMAs; thus, they are more suitable for the severe temperature-variation environments to which civil structures are exposed. Steel jackets of passive confinement are also prepared in order to compare the cyclic behavior of actively and passively confined concrete cylinders. For this purpose, monotonic and cyclic compressive loading tests are conducted to obtain axial and circumferential strain. Both strains are used to estimate the volumetric strains of concrete cylinders. Plastic strains from cyclic behavior are also estimated. For the cylinders jacketed by NiTiNb SMA wires, the monotonic axial behavior differs from the envelope of cyclic behavior. The plastic strains of the actively confined concrete show a similar trend to those of passive confinement. This study proposed plastic strain models for concrete confined by SMA wire or steel jackets. For the volumetric strain, the active jackets of NiTiNb SMA wires provide more energy dissipation than the passive jacket of steel

  16. Confined catalysis under two-dimensional materials

    Science.gov (United States)

    Li, Haobo; Xiao, Jianping; Bao, Xinhe

    2017-01-01

    Confined microenvironments formed in heterogeneous catalysts have recently been recognized as equally important as catalytically active sites. Understanding the fundamentals of confined catalysis has become an important topic in heterogeneous catalysis. Well-defined 2D space between a catalyst surface and a 2D material overlayer provides an ideal microenvironment to explore the confined catalysis experimentally and theoretically. Using density functional theory calculations, we reveal that adsorption of atoms and molecules on a Pt(111) surface always has been weakened under monolayer graphene, which is attributed to the geometric constraint and confinement field in the 2D space between the graphene overlayer and the Pt(111) surface. A similar result has been found on Pt(110) and Pt(100) surfaces covered with graphene. The microenvironment created by coating a catalyst surface with 2D material overlayer can be used to modulate surface reactivity, which has been illustrated by optimizing oxygen reduction reaction activity on Pt(111) covered by various 2D materials. We demonstrate a concept of confined catalysis under 2D cover based on a weak van der Waals interaction between 2D material overlayers and underlying catalyst surfaces. PMID:28533413

  17. Static current profile control and RFP confinement

    International Nuclear Information System (INIS)

    Scheffel, Jan; Mirza, Ahmed A.; Schnack, Dalton D.

    2013-01-01

    Static current profile control (CPC) is shown numerically to substantially enhance plasma confinement in the reversed-field pinch (RFP). By suitable application of an auxiliary electric field and adjustment of its internal location, width and amplitude, strongly decreased levels of dynamo fluctuations are obtained. The simulations are performed using a fully non-linear, resistive magnetohydrodynamic model, including the effects of ohmic heating as well as parallel and perpendicular heat conduction along stochastic field lines. The importance of controlling the parallel current profile in the core plasma to minimize the effects of tearing modes on confinement is thus confirmed. A near three-fold increase in energy confinement is found and poloidal plasma beta increases by 30% from 0.20 to 0.27. The edge heat flux is reduced to a third of that of the conventional RFP. The high-confinement phase is interrupted here by a crash, characterized by a rapid decrease in confinement. A detailed study of the crash phase is carried out by the standard Δ′ theory and a fully resistive linearized time-spectral method; the generalized weighted residual method. The analysis suggests that the instability is caused by pressure-driven, resistive g-modes. Inclusion of anisotropic thermal conduction reduces the linear growth rates. As compared with our earlier numerical studies of CPC in the RFP, employing feedback control, the present static control scheme should be more easily implemented experimentally. (paper)

  18. Reinforced confinement in a nuclear reactor

    International Nuclear Information System (INIS)

    Norman, H.

    1988-01-01

    The present invention concerns a nuclear reactor containing a reactor core, a swimming pool space that is filled and pressurized with a neutron-absorbing solution, a reactor tank, at least one heat exchanger, at least one inlet line, at least one return line and at least one circulation pump, where the said reactor tank is confined in the said swimming pool space and designed to be cooled with the aid of relatively pure water, which is fed by means of the said at least one circulating pump to the said reactor tank from the said heat exchanger via the said at least one inlet line and is returned to the heat exchanger via the said at least one return line. The problem that is to be solved by the invention is to design a reactor of the above type in such a way that a complete confinement of the primary circuit of the reactor is achieved at relatively low extra cost. This problem is solved by providing the reactor with a special confinement space that confines the heat exchanger, but not the reactor tank, with the confinement space and the swimming pool space being fashioned in the same concrete body

  19. Packing frustration in dense confined fluids.

    Science.gov (United States)

    Nygård, Kim; Sarman, Sten; Kjellander, Roland

    2014-09-07

    Packing frustration for confined fluids, i.e., the incompatibility between the preferred packing of the fluid particles and the packing constraints imposed by the confining surfaces, is studied for a dense hard-sphere fluid confined between planar hard surfaces at short separations. The detailed mechanism for the frustration is investigated via an analysis of the anisotropic pair distributions of the confined fluid, as obtained from integral equation theory for inhomogeneous fluids at pair correlation level within the anisotropic Percus-Yevick approximation. By examining the mean forces that arise from interparticle collisions around the periphery of each particle in the slit, we calculate the principal components of the mean force for the density profile--each component being the sum of collisional forces on a particle's hemisphere facing either surface. The variations of these components with the slit width give rise to rather intricate changes in the layer structure between the surfaces, but, as shown in this paper, the basis of these variations can be easily understood qualitatively and often also semi-quantitatively. It is found that the ordering of the fluid is in essence governed locally by the packing constraints at each single solid-fluid interface. A simple superposition of forces due to the presence of each surface gives surprisingly good estimates of the density profiles, but there remain nontrivial confinement effects that cannot be explained by superposition, most notably the magnitude of the excess adsorption of particles in the slit relative to bulk.

  20. Prevalence and factors associated with inappropriate use of treadmill exercise stress test for coronary artery disease: a cross-sectional study.

    Science.gov (United States)

    Silva, Antônio M L; Armstrong, Anderson C; Silveira, Fernando J C; Cavalcanti, Marcelo D; França, Fernando M F; Correia, Luis C L

    2015-06-16

    In some countries, the public health system has less availability when compared to the population covered by health insurance. In addition, inappropriate referrals for treadmill exercise stress test increase spending and lead to unnecessary interventions. We aim to determine the prevalence and characteristics of inappropriate referrals for treadmill exercise stress tests in the assessment of coronary artery disease (CAD), considering public and private health systems scenarios. A cross-sectional design was used to describe the frequency of inappropriate use of exercise testing in the diagnosis of CAD and to determine its predictors. We consecutively enrolled 191 patients from two outpatient facilities in Northeast Brazil. For inclusion, the exercise testing should be referred for the assessment of CAD. We performed logistic regression models to identify independent predictors of inappropriate use. Treadmill exercise stress tests were rated as inappropriate in 150 (78 %) patients. The majority of patients had low or very low pre-test probability of CAD. Presence of hypertension, diabetes and dyslipidemia were more frequent in the appropriate than inappropriate indications (71 %, 19 % and 29 % versus 43 %, 8 % and 16 %, respectively). Tests performed both at the public and private system showed high prevalence of inappropriate examinations, higher in the latter (57 % versus 87 %, P test referrals in the assessment of CAD were inappropriate. The availability of the method and not the estimate probability of CAD appear to be the underlying condition for a treadmill test referral.

  1. Investigating the Value of Section Scores for the "TOEFL iBT"® Test. "TOEFL iBT"® Research Report. TOEFL iBT-21. ETS Research Report RR-13-35

    Science.gov (United States)

    Sawaki, Yasuyo; Sinharay, Sandip

    2013-01-01

    This study investigates the value of reporting the reading, listening, speaking, and writing section scores for the "TOEFL iBT"® test, focusing on 4 related aspects of the psychometric quality of the TOEFL iBT section scores: reliability of the section scores, dimensionality of the test, presence of distinct score profiles, and the…

  2. Confinement in TPE-RX reversed field pinch

    International Nuclear Information System (INIS)

    Yagi, Y.; Bolzonella, T.; Canton, A.

    2001-01-01

    Characteristics of the confinement properties of a reversed field pinch (RFP), the TPE-RX (R/a=1.72/0.45 m, R and a are major and minor radii), are presented for the plasma current, I p of 0.2-0.4 MA. TPE-RX has been operational since 1998, and I p =0.5 MA and duration time of up to 0.1 s have been obtained separately. It is found that I p /N (=12x10 -14 Am, N is the line density) is higher than those of other RFPs and poloidal beta, β p , and energy confinement time, τ E , are 5-10% and 0.5-1 ms, respectively, which are comparable with those of other RFPs of comparable sizes (RFX and MST). Pulsed poloidal current drive has recently been tested and the result has shown a twofold improvement of β p and τ E . The improvement is discussed in terms of the dynamic trajectories in the F-Θ plane, where F and Θ are reversal and pinch parameters, respectively. The global confinement properties are compared between the locked and non-locked discharges, which yields a better understanding of the mode-locking phenomena in RFP plasmas. (author)

  3. Reformulation of the CBR Procedure, Report 2: Design, Construction, and Behavior Under Traffic of the Pavement Test Sections

    Science.gov (United States)

    2013-12-01

    thicknesses. The subbase material was delivered by dump trucks and placed in 5- to 7-in.-thick lifts. Each lift was compacted by 22 passes of a vibratory...supplied to the hydraulic ram. Since there was no independent system to directly measure the load being applied to the test tire, a calibration of the... Systems and Materials Division (ESMD), GSL. The research team consisted of Dr. Walter R. Barker, SOL Engineering Service, LLC, and Carlos R. Gonzalez

  4. A visual study of forced convection boiling. Part 2: Flow patterns and burnout for a round test section

    International Nuclear Information System (INIS)

    Kirby, G.J.; Staniforth, R.; Kinneir, J.H.

    1967-03-01

    The studies of boiling water at 25 p.s.i.a. reported here show the same flow patterns as in earlier tests in that the bubbles formed on the heater regained close to the heated surface to coalesce into large bubbles which eventually spanned the flow channel. Burnout tests were made and it was found there was a change of slope of the heat flux-subcooling curve. Further tests showed that this effect was due to a change in flow regime between burnout with much vapour present and burnout with just nucleate bubbles present. In the latter regime it was found that burnout is dependent only on the conditions local to the burnout point. Photography of the burnout region was practicable only when few bubbles were present but although pictures of the bubble over the burnout point were taken, no clear evidence on the mechanism of formation of the bubble could be gleaned. Some speculation on the cause of burnout in this regime is made in the light of these experiments. (author)

  5. Universality classes and critical phenomena in confined liquid systems

    Directory of Open Access Journals (Sweden)

    A.V. Chalyi

    2013-06-01

    Full Text Available It is well known that the similar universal behavior of infinite-size (bulk systems of different nature requires the same basic conditions: space dimensionality; number components of order parameter; the type (short- or long-range of the intermolecular interaction; symmetry of the fluctuation part of thermodynamical potential. Basic conditions of similar universal behavior of confined systems needs the same supplementary conditions such as the number of monolayers for a system confinement; low crossover dimensionality, i.e., geometric form of restricted volume; boundary conditions on limiting surfaces; physical properties under consideration. This review paper is aimed at studying all these conditions of similar universal behavior for diffusion processes in confined liquid systems. Special attention was paid to the effects of spatial dispersion and low crossover dimensionality. This allowed us to receive receiving correct nonzero expressions for the diffusion coefficient at the critical point and to take into account the specific geometric form of the confined liquid volume. The problem of 3D⇔2D dimensional crossover was analyzed. To receive a smooth crossover for critical exponents, the Kawasaki-like approach from the theory of mode coupling in critical dynamics was proposed. This ensured a good agreement between data of computer experiment and theoretical calculations of the size dependence of the critical temperature Tc(H of water in slitlike pores. The width of the quasi-elastic scattering peak of slow neutrons near the structural phase transition in the aquatic suspensions of plasmatic membranes (mesostructures with the typical thickness up to 10 nm was studied. It was shown that the width of quasi-elastic peak of neutron scattering decreases due to the process of cell proliferation, i.e., with an increase of the membrane size (including the membrane thickness. Thus, neutron studies could serve as an additional diagnostic test for the

  6. The Knot Spectrum of Confined Random Equilateral Polygons

    Directory of Open Access Journals (Sweden)

    Diao Y.

    2014-01-01

    Full Text Available It is well known that genomic materials (long DNA chains of living organisms are often packed compactly under extreme confining conditions using macromolecular self-assembly processes but the general DNA packing mechanism remains an unsolved problem. It has been proposed that the topology of the packed DNA may be used to study the DNA packing mechanism. For example, in the case of (mutant bacteriophage P4, DNA molecules packed inside the bacteriophage head are considered to be circular since the two sticky ends of the DNA are close to each other. The DNAs extracted from the capsid without separating the two ends can thus preserve the topology of the (circular DNAs. It turns out that the circular DNAs extracted from bacteriophage P4 are non-trivially knotted with very high probability and with a bias toward chiral knots. In order to study this problem using a systematic approach based on mathematical modeling, one needs to introduce a DNA packing model under extreme volume confinement condition and test whether such a model can produce the kind of knot spectrum observed in the experiments. In this paper we introduce and study a model of equilateral random polygons con_ned in a sphere. This model is not meant to generate polygons that model DNA packed in a virus head directly. Instead, the average topological characteristics of this model may serve as benchmark data for totally randomly packed circular DNAs. The difference between the biologically observed topological characteristics and our benchmark data might reveal the bias of DNA packed in the viral capsids and possibly lead to a better understanding of the DNA packing mechanism, at least for the bacteriophage DNA. The purpose of this paper is to provide information about the knot spectrum of equilateral random polygons under such a spherical confinement with length and confinement ratios in a range comparable to circular DNAs packed inside bacteriophage heads.

  7. Transition metal catalysis in confined spaces.

    Science.gov (United States)

    Leenders, Stefan H A M; Gramage-Doria, Rafael; de Bruin, Bas; Reek, Joost N H

    2015-01-21

    Transition metal catalysis plays an important role in both industry and in academia where selectivity, activity and stability are crucial parameters to control. Next to changing the structure of the ligand, introducing a confined space as a second coordination sphere around a metal catalyst has recently been shown to be a viable method to induce new selectivity and activity in transition metal catalysis. In this review we focus on supramolecular strategies to encapsulate transition metal complexes with the aim of controlling the selectivity via the second coordination sphere. As we will discuss, catalyst confinement can result in selective processes that are impossible or difficult to achieve by traditional methods. We will describe the template-ligand approach as well as the host-guest approach to arrive at such supramolecular systems and discuss how the performance of the catalyst is enhanced by confining it in a molecular container.

  8. Do swingers self-identify as swingers when attending STI services for testing? A cross-sectional study.

    Science.gov (United States)

    Spauwen, Laura W L; Niekamp, Anne-Marie; Hoebe, Christian J P A; Dukers-Muijrers, Nicole H T M

    2018-01-30

    Swingers, that is, members of a heterosexual couple who, as a couple, had sex with other couples and/or singles within the swinger's subculture, are a hidden population with substantial rates of sexually transmitted infections (STIs) and high-risk sexual behaviour. Information on swingers' self-identification to be a swinger, their risk perception and attitudes about STI testing and safe sex will help to reveal swingers who are hidden while in care, to address them with targeted strategies. We used data from a convenience sample of 289 swingers from our Dutch STI clinic patient registry between 2009 and 2012 (median age 45 years; 49% women; STI positivity 13%, no condom in vaginal sex: 57%). Participants filled in a self-administered questionnaire on sexual behaviour and answered statements about self-identification, risk perception and attitudes about STI testing and safe sex. Of all participating registered swingers, 56% self-identified as a swinger. Safe sex was reportedly deemed important (77%). Overall, 72%, 62% and 56% reported that STI testing, partner notification and condom use is the norm in the swinger community. The latter was reported more often by self-identified swingers compared with non-self-identified swingers. Self-identified swingers further swinged more often, had more partners and more often swinged at home parties than non-self-identified swingers. About half of STI clinic attending swingers whose sexual behaviour agrees with the definition of swinging are neutral/do not identify themselves to be a swinger. As many STI clinics internationally not specifically ask clients about their swinging behaviour, swingers may be a missed target population in care. Implementation of routine questions addressing behaviour (thus not only asking whether someone is a swinger) in STI clinics is feasible and facilitated by swingers' positive norm towards STI prevention and testing. Implementing routine swinger questions contribute to effective STI services

  9. Experimental Investigation of the Influence of Confining Stress on Hard Rock Fragmentation Using a Conical Pick

    Science.gov (United States)

    Li, Xibing; Wang, Shaofeng; Wang, Shanyong

    2018-01-01

    High geostress is a prominent condition in deep excavations and affects the cuttability of deep hard rock. This study aims to determine the influence of confining stress on hard rock fragmentation as applied by a conical pick. Using a true triaxial test apparatus, static and coupled static and dynamic loadings from pick forces were applied to end faces of cubic rock specimens to break them under biaxial, uniaxial and stress-free confining stress conditions. The cuttability indices (peak pick force, insertion depth and disturbance duration), failure patterns and fragment sizes were measured and compared to estimate the effects of confining stress. The results show that the rock cuttabilities decreased in order from rock breakages under stress-free conditions to uniaxial confining stress and then to biaxial confining stress. Under biaxial confining stress, only flake-shaped fragments were stripped from the rock surfaces under the requirements of large pick forces or disturbance durations. As the level of uniaxial confining stress increased, the peak pick force and the insertion depth initially increased and then decreased, and the failure patterns varied from splitting to partial splitting and then to rock bursts with decreasing average fragment sizes. Rock bursts will occur under elastic compression via ultra-high uniaxial confining stresses. There are two critical uniaxial confining stress levels, namely stress values at which peak pick forces begin to decrease and improve rock cuttability, and those at which rock bursts initially occur and cutting safety decreases. In particular, hard rock is easiest to split safely and efficiently under stress-free conditions. Moreover, coupled static preloading and dynamic disturbance can increase the efficiency of rock fragmentation with increasing preloading levels and disturbance amplitudes. The concluding remarks confirm hard rock cuttability using conical pick, which can improve the applicability of mechanical excavation in

  10. Higher representations: Confinement and large N

    International Nuclear Information System (INIS)

    Sannino, Francesco

    2005-01-01

    We investigate the confining phase transition as a function of temperature for theories with dynamical fermions in the two index symmetric and antisymmetric representation of the gauge group. By studying the properties of the center of the gauge group we predict for an even number of colors a confining phase transition, if second order, to be in the universality class of Ising in three dimensions. This is due to the fact that the center group symmetry does not break completely for an even number of colors. For an odd number of colors the center group symmetry breaks completely. This pattern remains unaltered at a large number of colors. The confining/deconfining phase transition in these theories at large and finite N is not mapped in the one of super Yang-Mills theory. We extend the Polyakov loop effective theory to describe the confining phase transition of the theories studied here for a generic number of colors. Our results are not modified when adding matter in the same higher dimensional representations of the gauge group. We comment on the interplay between confinement and chiral symmetry in these theories and suggest that they are ideal laboratories to shed light on this issue also for ordinary QCD. We compare the free energy as a function of temperature for different theories. We find that the conjectured thermal inequality between the infrared and ultraviolet degrees of freedom computed using the free energy does not lead to new constraints on asymptotically free theories with fermions in higher dimensional representations of the gauge group. Since the center of the gauge group is an important quantity for the confinement properties at zero temperature our results are relevant here as well

  11. Magnetic properties of confined electron gas

    International Nuclear Information System (INIS)

    Felicio, J.R.D. de.

    1977-04-01

    The effects of confinement by a two or three-dimensional harmonic potential on the magnetic properties of a free electron gas are investigated using the grand-canonical ensemble framework. At high temperatures an extension of Darwin's, Felderhof and Raval's works is made taking into account spin effects at low temperature. A comprehensive description of the magnetic properties of a free electron gas is given. The system is regarded as finite, but the boundary condition psi=0 is not introduced. The limits of weak and strong confinement are also analysed [pt

  12. Testing an OMERACT MRI scoring system for peripheral psoriatic arthritis in cross-sectional and longitudinal settings

    DEFF Research Database (Denmark)

    McQueen, Fiona; Lassere, Marissa; Duer-Jensen, Anne

    2009-01-01

    OBJECTIVE: Magnetic resonance imaging (MRI) is increasingly used to measure articular inflammation and damage in patients with psoriatic arthritis (PsA). We evaluated the reliability of a new OMERACT PsA MRI scoring system, PsAMRIS, in PsA fingers. METHODS: In 2 separate studies, MRI scans were o......, reliability for change scores was acceptable only for synovitis and tenosynovitis. CONCLUSION: Further development and testing of the PsAMRIS is planned to improve its performance as a clinical and research tool to identify and measure pathology in peripheral joint PsA....

  13. Behavior of FRP-Confined Concrete-Filled Steel Tube Columns

    Directory of Open Access Journals (Sweden)

    Yiyan Lu

    2014-05-01

    Full Text Available This paper presents the results of an experimental study into the behavior of concrete-filled steel tube columns confined by fiber-reinforced polymer (FRP. Eleven columns were tested to investigate the effects of the FRP layer number, the thickness of the steel tube and concrete strength on their load capacity and axial deformation capacity. The experimental results indicated that the FRP wrap can effectively confine the concrete expansion and delay the local buckling of the steel tube. Both the load capacity and the axial deformation capacity of concrete-filled steel tube columns can be substantially enhanced with FRP confinement. A model is proposed to predict the load capacity of the FRP-confined concrete-filled steel tube columns. The predicted results are generally in good agreement with the experimental ones obtained in this study and in the literature.

  14. Test of universal rise of hadronic total cross sections based on πp, Kp and pp, pp scatterings

    International Nuclear Information System (INIS)

    Ishida, Muneyuki; Igi, Keiji

    2009-01-01

    Recently, there have been several evidences that the hadronic total cross section σ tot is proportional to Blog 2 s, which is consistent with the Froissart unitarity bound. The COMPETE Collaboration has further assumed σ tot ≅Blog 2 (s/s 0 )+Z to extend its universal rise with the common values of B and s 0 for all hadronic scatterings to reduce the number of adjustable parameters. It was suggested that the coefficient B was universal in the arguments of the color glass condensate of QCD in recent years. However, there has been no rigorous proof yet based only on QCD. We attempt to investigate the value of B for π ± p, K ± p and pp, pp scatterings, respectively, through the search for the simultaneous best fit to the experimental σ tot and ρ ratios at high energies. The σ tot at the resonance- and intermediate-energy regions has also been exploited as a duality constraint based on the special form of the finite-energy sum rule. We estimate the values of B, s 0 , and Z individually for π ± p, K ± p and pp, pp scatterings without using the universality hypothesis. It turns out that the values of B are mutually consistent within 1 standard deviation. It has to be stressed that we cannot obtain such a definite conclusion without the duality constraint. It is also interesting to note that the values of Z for πp, Kp, and p(p)p approximately satisfy the ratio 2 ratio 2 ratio 3 predicted by the quark model. The obtained value of B for p(p)p is B pp =0.280±0.015 mb, which predicts σ tot pp =108.0±1.9 mb and ρ pp =0.131±0.0025 at the LHC energy √(s)=14 TeV.

  15. A study on spalling in soft rock under low confining stress

    International Nuclear Information System (INIS)

    Tomita, Atsunori; Ebina, Takahito; Toida, Masaru; Shirasagi, Suguru; Kishida, Kiyoshi; Adachi, Toshihisa

    2007-01-01

    The aim of this paper is to study spalling in soft rock excavation. During the test cavern excavation of the radioactive waste disposal project, spalling occurred. Therefore, it has been estimated performing the stress path simulation test and measuring the induced stress. In the stress path simulation test, the splitting failure has been confirmed under low confining stress. In the induced stress measurements, the rock mass around the cavern has shifted to the low radial confinement. Hence, spalling in soft rock was interpreted by the splitting failure caused by the induced stress under low confinement. Furthermore, the failure zone was proved by the numerical analysis applying the criterion based on the results of the above triaxial test. (author)

  16. Wall adjustment strategy software for use with the NASA Langley 0.3-meter transonic cryogenic tunnel adaptive wall test section

    Science.gov (United States)

    Wolf, Stephen W. D.

    1988-01-01

    The Wall Adjustment Strategy (WAS) software provides successful on-line control of the 2-D flexible walled test section of the Langley 0.3-m Transonic Cryogenic Tunnel. This software package allows the level of operator intervention to be regulated as necessary for research and production type 2-D testing using and Adaptive Wall Test Section (AWTS). The software is designed to accept modification for future requirements, such as 3-D testing, with a minimum of complexity. The WAS software described is an attempt to provide a user friendly package which could be used to control any flexible walled AWTS. Control system constraints influence the details of data transfer, not the data type. Then this entire software package could be used in different control systems, if suitable interface software is available. A complete overview of the software highlights the data flow paths, the modular architecture of the software and the various operating and analysis modes available. A detailed description of the software modules includes listings of the code. A user's manual is provided to explain task generation, operating environment, user options and what to expect at execution.

  17. Well responses to barometric-pressure fluctuations in confined and semi-confined aquifers

    Science.gov (United States)

    Mohammed, G. A.; Jin, W.; Butler, J. J., Jr.; Reboulet, E. C.

    2009-04-01

    Modern data logger and sensor technology enable well responses to barometric pressure changes to be monitored at a high frequency and precision. In this presentation, we demonstrate that such monitoring data can be utilized not just for the conventional calculation of a well's barometric efficiency but also to provide valuable information for site characterization applications. We investigate the water-level responses of wells in confined and semi-confined aquifers to changes in barometric pressure and show how simple analytical solutions can be fit to experimentally determined barometric response functions to place bounds on the properties of the confining bed. We demonstrate our approach at the Larned Research Site, located along the Arkansas River in south-central Kansas in the Great Plains region of the United States. The site contains monitoring wells tapping an unconsolidated, semi-confined aquifer (High Plains Aquifer) overlain by a clay unit and a shallow, unconfined aquifer. Water levels and atmospheric pressure have been monitored in the wells at 15-minute intervals for up to seven years. The spatial and temporal changes in the barometric response functions provide important insights on the degree of confinement and its change in space and time. Short term (hour or less) response functions indicate a classical confined aquifer, whereas long term responses (day) show semi-confined behavior, an indication that the air pressure exerted on the water table is being transmitted downward through the confining bed. The barometric response functions vary little in space, indicating the homogeneity of the confining bed, but do vary temporally as a function of the water table elevation and the pneumatic diffusivity of the vadose zone.

  18. The use of semi-quantitative tests at Cesarean section delivery for the differentiation of canine fetal fluids from maternal urine on the basis of biochemical characteristics.

    Science.gov (United States)

    Balogh, Orsolya; Roch, Marie; Keller, Stefanie; Michel, Erika; Reichler, Iris M

    2017-01-15

    In dogs, there is no diagnostic test to identify and differentiate fetal fluids from maternal urine in the event that a clear-yellowish vulvar discharge is observed pre-whelping. The objective of this study was to find a test that could easily and accurately identify rupture of the fetal membranes preceding parturition. Maternal urine, and amniotic fluid (AMF) and allantoic fluid (ALF) from only one fetus per bitch, were collected intraoperatively during Cesarean section. Specific gravity (SG) was analyzed with a refractometer, whereas the presence of leukocytes, protein, glucose, ketones, bilirubin, urobilinogen, nitrite, erythrocyte/hemoglobin (Hb), and the pH were assessed using a urine dipstick (Combur-Test ® ). Combined calcium and magnesium (Ca/Mg) content were evaluated with the Total Hardness Test. The AmniSure test, which detects rupture of fetal membranes in women on the basis of the presence of human placental alpha microglobulin-1, was also performed on canine AMF, ALF, and urine. Data were analyzed using the Fisher's exact test, Wilcoxon signed-rank test, and Pearson's correlation. Sensitivity, specificity, and positive and negative likelihood ratios (LR) were calculated for parameters with significant difference between urine and both fetal fluids. Maternal urine had higher SG and lower leukocyte, protein, Hb, and Ca/Mg content than AMF and ALF. Glucose was more often present in AMF (n = 17) and ALF (n = 12) than in urine (n = 1), whereas ketone bodies were rarely detected in ALF compared with urine. Bilirubin content was higher in urine and ALF than in AMF. AMF pH was less variable and higher than the pH of ALF or urine. The AmniSure was negative in all samples tested. Sensitivity and specificity for SG and for the detection of leukocytes, protein, glucose, Hb, Ca/Mg, and glucose without ketones in urine and fetal fluids were between 42% to 100% and 65% to 100%, respectively. Best positive LR was achieved for the detection of glucose without ketones

  19. Inertial Confinement Fusion at Los Alamos

    International Nuclear Information System (INIS)

    Cartwright, D.C.

    1989-09-01

    This report discusses the following topics on Inertial Confinement Fusion: ICF contributions to science and technology; target fabrication; laser-target interaction; KrF laser development; advanced KrF lasers; KrF laser technology; and plasma physics for light-ion program

  20. Large hadronic structures and colour confinement

    International Nuclear Information System (INIS)

    Abbas, Afsar; Paria, Lina; Abbas, Samar

    1999-01-01

    Colour confinement is an experimentally well established property of QCD at temperature T = 0. Though it has not been conclusively demonstrated in QCD, it is universally believed to be true. Several model calculations indicate that indeed the 3-q and qq-bar colour-singlet states are more bound than for example the colour octet, decuplet representations

  1. Dynamics of water confined in clay minerals

    International Nuclear Information System (INIS)

    Le Caer, S.; Pommeret, S.; Renault, J.Ph.; Lima, M.; Righini, R.; Gosset, D.; Simeone, D.; Bergaya, F.

    2012-01-01

    Ultrafast infrared spectroscopy of the O-D stretching mode of dilute HOD in H 2 O probes the local environment and the hydrogen bond network of confined water. The dynamics of water molecules confined in the interlayer space of montmorillonites (Mt) and in interaction with two types of cations (Li + and Ca 2+ ) but also with the negatively charged siloxane surface are studied. The results evidence that the OD vibrational dynamics is significantly slowed down in confined media: it goes from 1.7 ps in neat water to 2.6 Ps in the case of Li + cations with two water pseudo-layers (2.2-2.3 ps in the case of Ca 2+ cations) and to 4.7 ps in the case of Li + cations with one water pseudo-layer. No significant difference between the two cations is noticed. In this 2D confined geometry (the interlayer space being about 0.6 nm for two water pseudo-layers), the relaxation time constants obtained are comparable to the ones measured in analogous concentrated salt solutions. Nevertheless, and in strong opposition to the observations performed in the liquid phase, anisotropy experiments evidence the absence of rotational motions on a 5 ps time scale, proving that the hydrogen bond network in the interlayer space of the clay mineral is locked at this time scale. (authors)

  2. Confinement, hidden color and multibaryon states

    International Nuclear Information System (INIS)

    Nicolescu, B.

    1979-01-01

    Ideas and theoretical results on multiquark states are reviewed. The measuring of concepts such as 'quarks', 'color' and 'confinement' is analysed first then the possible existence of multiquark states is discussed. the example of dibaryons is used to study their properties in the bag model and in the Dual Topological Unitarization theory [fr

  3. Ultrafast chemistry in complex and confined systems

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 116; Issue 1. Ultrafast chemistry in complex and ... Recent applications of ultrafast laser spectroscopy and computer simulations revealed that chemistry in a confined environment is fundamentally different from that in ordinary solutions. Many recent examples of slow ...

  4. Mesoscale simulations of confined Nafion thin films

    Science.gov (United States)

    Vanya, P.; Sharman, J.; Elliott, J. A.

    2017-12-01

    The morphology and transport properties of thin films of the ionomer Nafion, with thicknesses on the order of the bulk cluster size, have been investigated as a model system to explain the anomalous behaviour of catalyst/electrode-polymer interfaces in membrane electrode assemblies. We have employed dissipative particle dynamics (DPD) to investigate the interaction of water and fluorocarbon chains, with carbon and quartz as confining materials, for a wide range of operational water contents and film thicknesses. We found confinement-induced clustering of water perpendicular to the thin film. Hydrophobic carbon forms a water depletion zone near the film interface, whereas hydrophilic quartz results in a zone with excess water. There are, on average, oscillating water-rich and fluorocarbon-rich regions, in agreement with experimental results from neutron reflectometry. Water diffusivity shows increasing directional anisotropy of up to 30% with decreasing film thickness, depending on the hydrophilicity of the confining material. A percolation analysis revealed significant differences in water clustering and connectivity with the confining material. These findings indicate the fundamentally different nature of ionomer thin films, compared to membranes, and suggest explanations for increased ionic resistances observed in the catalyst layer.

  5. Enhanced heat transfer in confined pool boiling

    NARCIS (Netherlands)

    Rops, C.M.; Lindken, R.; Velthuis, J.F.M.; Westerweel, J.

    2009-01-01

    We report the results of an experimental investigation of the heat transfer during nucleate boiling on a spatially confined boiling surface. The heat flux as a function of the boiling surface temperature was measured in pool boiling pots with diameters ranging from 15 mm down to 4.5 mm. It was found

  6. Perspectives on confinement in helical systems

    International Nuclear Information System (INIS)

    Itoh, Kimitaka; Itoh, Sanae

    1989-01-01

    A review on recent experimental results and theoretical models on anomalous transport and density limit in toroidal helical devices is presented. Importance of transport problems is discussed. Experiments on Heliotron-E, Wendelstein-VIIA and new devices, i.e., ATF, Wendelstein-VIIAS and CHS, are reviewed and an overview on confinement property is given. From recent experimental results one sees that there are anomalous transport, which increases with temperature, and density limit, and that they limit the energy confinement time as well as the attainable beta value. The confinement characteristics of the scrape off layer plasma and loss cone loss are discussed, and perspectives on the high temperature plasma are given. These anomalous transport and density limit will be difficult obstacles in realizing a reactor grade plasma in helical systems. It is an urgent task to draw a realistic picture of the confinement based on the present data base. The relevant knowledge now would be critically essential for the successful development of the research in 1990's. (author) 102 refs

  7. Hohlraum manufacture for inertial confinement fusion

    International Nuclear Information System (INIS)

    Foreman, L.R.; Gobby, P.; Bartos, J.

    1994-01-01

    Hohlraums are an integral part of indirect drive targets for Inertial Confinement Fusion (ICF) research. Hohlraums are made by an electroforming process that combines elements of micromachining and coating technology. The authors describe how these target element are made and extension of the method that allow fabrication of other, more complex target components

  8. Clusters of polyhedra in spherical confinement

    Science.gov (United States)

    Teich, Erin G.; van Anders, Greg; Klotsa, Daphne; Dshemuchadse, Julia; Glotzer, Sharon C.

    2016-01-01

    Dense particle packing in a confining volume remains a rich, largely unexplored problem, despite applications in blood clotting, plasmonics, industrial packaging and transport, colloidal molecule design, and information storage. Here, we report densest found clusters of the Platonic solids in spherical confinement, for up to N=60 constituent polyhedral particles. We examine the interplay between anisotropic particle shape and isotropic 3D confinement. Densest clusters exhibit a wide variety of symmetry point groups and form in up to three layers at higher N. For many N values, icosahedra and dodecahedra form clusters that resemble sphere clusters. These common structures are layers of optimal spherical codes in most cases, a surprising fact given the significant faceting of the icosahedron and dodecahedron. We also investigate cluster density as a function of N for each particle shape. We find that, in contrast to what happens in bulk, polyhedra often pack less densely than spheres. We also find especially dense clusters at so-called magic numbers of constituent particles. Our results showcase the structural diversity and experimental utility of families of solutions to the packing in confinement problem. PMID:26811458

  9. Somersault of Paramecium in extremely confined environments

    Science.gov (United States)

    Jana, Saikat; Eddins, Aja; Spoon, Corrie; Jung, Sunghwan

    2015-08-01

    We investigate various swimming modes of Paramecium in geometric confinements and a non-swimming self-bending behavior like a somersault, which is quite different from the previously reported behaviors. We observe that Paramecia execute directional sinusoidal trajectories in thick fluid films, whereas Paramecia meander around a localized region and execute frequent turns due to collisions with adjacent walls in thin fluid films. When Paramecia are further constrained in rectangular channels narrower than the length of the cell body, a fraction of meandering Paramecia buckle their body by pushing on the channel walls. The bucking (self-bending) of the cell body allows the Paramecium to reorient its anterior end and explore a completely new direction in extremely confined spaces. Using force deflection method, we quantify the Young’s modulus of the cell and estimate the swimming and bending powers exerted by Paramecium. The analysis shows that Paramecia can utilize a fraction of its swimming power to execute the self-bending maneuver within the confined channel and no extra power may be required for this new kind of self-bending behavior. This investigation sheds light on how micro-organisms can use the flexibility of the body to actively navigate within confined spaces.

  10. Dynamics of Colloids Confined in Microcylinders

    NARCIS (Netherlands)

    Ghosh, Somnath; Wijnperle, Daniël; Mugele, Friedrich Gunther; Duits, Michael H.G.

    2016-01-01

    We studied both global and local effects of cylindrical confinement on the diffusive behavior of hard sphere (HS) colloids. Using confocal scanning laser microscopy (CSLM) and particle tracking, we measured the mean squared displacement (MSD) of 1 micron sized silica particles in water–glycerol.

  11. Structure of polymer chains under confinement

    Indian Academy of Sciences (India)

    cluded volume interactions (so-called regime of “semi-dilute cigars”). For confined charged polymers, a peak is observed whose intensity increases with molecular weight and the asymptotic 1/q scattering region is extended compared to the bulk. We infer that the chains are sufficiently extended, under the influence of ...

  12. Transition metal catalysis in confined spaces

    NARCIS (Netherlands)

    Leenders, S.H.A.M.; Gramage-Doria, R.; de Bruin, B.; Reek, J.N.H.

    2015-01-01

    Transition metal catalysis plays an important role in both industry and in academia where selectivity, activity and stability are crucial parameters to control. Next to changing the structure of the ligand, introducing a confined space as a second coordination sphere around a metal catalyst has

  13. Inertial Confinement Fusion at Los Alamos

    International Nuclear Information System (INIS)

    Cartwright, D.C.

    1989-09-01

    This report discusses the following topics on inertial confinement fusion: distribution of electron-beam energy in KrF laser media; electron collision processes in KrF laser media; Krf laser kinetics; and properties of the KrF laser medium

  14. Confining strings revisited - a short comment

    International Nuclear Information System (INIS)

    Botelho, Luiz C.L.

    2000-03-01

    We show that Polyakov's confining string Nucl. Phys. B486, (1997) 23, is the author's previously proposed self-avoiding extrinsic strings (Luiz C.L. Botelho), Rev. Bras. Fis. 16, 279, (1986); CALTECH-preprint 68, 1444, (1987); J. Math. Phys. 30 (9), (1989), 2160). (author)

  15. Confining strings revisited - a short comment

    Energy Technology Data Exchange (ETDEWEB)

    Botelho, Luiz C.L. [Universidade Federal Rural do Rio de Janeiro, RJ (Brazil). Dept. de Fisica

    2000-03-01

    We show that Polyakov's confining string Nucl. Phys. B486, (1997) 23, is the author's previously proposed self-avoiding extrinsic strings (Luiz C.L. Botelho), Rev. Bras. Fis. 16, 279, (1986); CALTECH-preprint 68, 1444, (1987); J. Math. Phys. 30 (9), (1989), 2160. (author)

  16. Cross-Sectional Analysis of the Utility of Pulmonary Function Tests in Predicting Emphysema in Ever-Smokers

    Directory of Open Access Journals (Sweden)

    Farrah Kheradmand

    2011-04-01

    Full Text Available Emphysema is largely an under-diagnosed medical condition that can exist in smokers in the absence of airway obstruction. We aimed to determine the sensitivity and specificity of pulmonary function tests (PFTs in assessing emphysema using quantitative CT scans as the reference standard. We enrolled 224 ever-smokers (current or former over the age of 40. CT of thorax was used to quantify the low attenuation area (% emphysema, and to measure the standardized airway wall thickness. PFTs were used individually and in combination to predict their ability to discriminate radiographic emphysema. Significant emphysema (>7% was detected in 122 (54% subjects. Twenty six (21% emphysema subjects had no evidence of airflow obstruction (FEV1/FVC ratio 23% emphysema showed airflow obstruction. The sensitivity and specificity of spirometry for detecting radiographic emphysema were 79% and 75%, respectively. Standardized airway wall thickness was increased in subjects with airflow obstruction, but did not correlate with emphysema severity. In this cohort of lifetime ever-smokers, PFTs alone were inadequate for diagnosing emphysema. Airway wall thickness quantified by CT morphometry was associated with airflow limitation, but not with emphysema indicating that the heterogeneous nature of lung disease in smokers may represent distinct phenotypes.

  17. Do Neurocognitive SCAT3 Baseline Test Scores Differ Between Footballers (Soccer) Living With and Without Disability? A Cross-Sectional Study.

    Science.gov (United States)

    Weiler, Richard; van Mechelen, Willem; Fuller, Colin; Ahmed, Osman Hassan; Verhagen, Evert

    2018-01-01

    To determine if baseline Sport Concussion Assessment Tool, third Edition (SCAT3) scores differ between athletes with and without disability. Cross-sectional comparison of preseason baseline SCAT3 scores for a range of England international footballers. Team doctors and physiotherapists supporting England football teams recorded players' SCAT 3 baseline tests from August 1, 2013 to July 31, 2014. A convenience sample of 249 England footballers, of whom 185 were players without disability (male: 119; female: 66) and 64 were players with disability (male learning disability: 17; male cerebral palsy: 28; male blind: 10; female deaf: 9). Between-group comparisons of median SCAT3 total and section scores were made using nonparametric Mann-Whitney-Wilcoxon ranked-sum test. All footballers with disability scored higher symptom severity scores compared with male players without disability. Male footballers with learning disability demonstrated no significant difference in the total number of symptoms, but recorded significantly lower scores on immediate memory and delayed recall compared with male players without disability. Male blind footballers' scored significantly higher for total concentration and delayed recall, and male footballers with cerebral palsy scored significantly higher on balance testing and immediate memory, when compared with male players without disability. Female footballers with deafness scored significantly higher for total concentration and balance testing than female footballers without disability. This study suggests that significant differences exist between SCAT3 baseline section scores for footballers with and without disability. Concussion consensus guidelines should recognize these differences and produce guidelines that are specific for the growing number of athletes living with disability.

  18. Primary health care teams put to the test a cross-sectional study from Austria within the QUALICOPC project.

    Science.gov (United States)

    Hoffmann, Kathryn; George, Aaron; Dorner, Thomas E; Süß, Katharina; Schäfer, Willemijn L A; Maier, Manfred

    2015-11-16

    Multidisciplinary Primary Health Care Teams (PHCT) provide a comprehensive approach to address the social and health needs of communities. It was the aim of this analysis to assess the number of PHCT in Austria, a country with a weak PHC system, and to compare preventive activities, psychosocial care, and work satisfaction between GPs who work and those who do not work in PHCT. Within the QUALICOPC study, data collection was performed between November 2011 and May 2012, utilizing a standardized questionnaire for GPs. A stratified sample of GPs from across Austria was invited. Statistical analyses included descriptive statistics and tests. Data from 171 GPs questionnaires were used for this analysis. Of these, 61.1 % (n = 113) had a mono-disciplinary office, 26.3 % (n = 45) worked in an office consisting of GP, receptionist and one additional primary care profession, and 7.6 % (n = 13) worked in a larger PHCT. GPs that worked in larger PHCT were younger and more involved in psychosocial and preventive care. No differences were found with regard to work satisfaction or workload. This study gives insight into the structures of PHC in Austria. The results indicate a low number of PHCT; however, the overall return rate in our sample was low with more male GPs, more GPs from urban areas and more GPs working in offices together with other physicians than the national average. Younger GPs demonstrate a greater tendency to implement this primary care practice model in their practices, which seems to be associated with an emphasis in psychosocial and preventive care. If Austria is to increase the number of PHC teams, the country should embrace the work of young GPs and should offer relevant support for PHCT. Future developments could be guided by considering effective models of good practice and governmental support as in other countries.

  19. 29 CFR 1915.94 - Work in confined or isolated spaces.

    Science.gov (United States)

    2010-07-01

    ....94 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT General Working Conditions § 1915.94 Work in confined or isolated spaces. The provisions of this section shall...

  20. Audit of HIV counselling and testing services among primary healthcare facilities in Cameroon: a protocol for a multicentre national cross-sectional study.

    Science.gov (United States)

    Tianyi, Frank-Leonel; Tochie, Joel Noutakdie; Agbor, Valirie Ndip; Kadia, Benjamin Momo

    2018-03-01

    HIV testing is an invaluable entry point to prevention, care and treatment services for people living with HIV and AIDS. Poor adherence to recommended protocols and guidelines reduces the performance of rapid diagnostic tests, leading to misdiagnosis and poor estimation of HIV seroprevalence. This study seeks to evaluate the adherence of primary healthcare facilities in Cameroon to recommended HIV counselling and testing (HCT) procedures and the impact this may have on the reliability of HIV test results. This will be an analytical cross-sectional study involving primary healthcare facilities from all the 10 regions of Cameroon, selected by a multistaged random sampling of primary care facilities in each region. The study will last for 9 months. A structured questionnaire will be used to collect general information concerning the health facility, laboratory and other departments involved in the HCT process. The investigators will directly observe at least 10 HIV testing processes in each facility and fill out the checklist accordingly. Clearance has been obtained from the National Ethical Committee to carry out the study. Informed consent will be sought from the patients to observe the HIV testing process. The final study will be published in a peer-reviewed journal and the findings presented to health policy-makers and the general public. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Materials program plan for inertial confinement fusion

    Energy Technology Data Exchange (ETDEWEB)

    Garde, A.; Hall, B.O.; Harkness, S.D.; Maiya, P.S.; Rechtin, M.D.; Li, C.Y.

    1979-08-01

    The effect of the irradiation environment on the microstructure of materials is studied. A major part of the initial activity in this area will be aimed toward evaluating the importance of pulse effects on microstructural development. The development effort that is necessary to cope with the high cycle loading of the first wall structure is studied. The loading pulses are expected to range from 1 to 20 per second (3 x 10/sup 7/ to 6 x 10/sup 8//year), thus creating a high cycle fatigue problem for any long-lived first wall structure. The interrelationship between specimen and component testing is a major issue in this section. Static mechanical property requirements are also considered here. Lithium compatibility is treated. The final section integrates the conclusions reached in the body of the report into a unified strategy that suggests a particular effort level to support major program milestones.

  2. Materials program plan for inertial confinement fusion

    International Nuclear Information System (INIS)

    Garde, A.; Hall, B.O.; Harkness, S.D.; Maiya, P.S.; Rechtin, M.D.; Li, C.Y.

    1979-08-01

    The effect of the irradiation environment on the microstructure of materials is studied. A major part of the initial activity in this area will be aimed toward evaluating the importance of pulse effects on microstructural development. The development effort that is necessary to cope with the high cycle loading of the first wall structure is studied. The loading pulses are expected to range from 1 to 20 per second (3 x 10 7 to 6 x 10 8 /year), thus creating a high cycle fatigue problem for any long-lived first wall structure. The interrelationship between specimen and component testing is a major issue in this section. Static mechanical property requirements are also considered here. Lithium compatibility is treated. The final section integrates the conclusions reached in the body of the report into a unified strategy that suggests a particular effort level to support major program milestones

  3. Confinement Effect on Material Properties of RC Beams Under Flexure

    Science.gov (United States)

    Kulkarni, Sumant; Shiyekar, Mukund Ramchandra; Shiyekar, Sandip Mukund

    2017-12-01

    In structural analysis, especially in indeterminate structures, it becomes essential to know the material and geometrical properties of members. The codal provisions recommend elastic properties of concrete and steel and these are fairly accurate enough. The stress-strain curve for concrete cylinder or a cube specimen is plotted. The slope of this curve is modulus of elasticity of plain concrete. Another method of determining modulus of elasticity of concrete is by flexural test of a beam specimen. The modulus of elasticity most commonly used for concrete is secant modulus. The modulus of elasticity of steel is obtained by performing a tension test of steel bar. While performing analysis by any software for high rise building, cross area of plain concrete is taken into consideration whereas effects of reinforcement bars and concrete confined by stirrups are neglected. Present aim of study is to determine elastic properties of reinforced cement concrete beam. Two important stiffness properties such as AE and EI play important role in analysis of high rise RCC building idealized as plane frame. The experimental program consists of testing of beams (model size 150 × 150 × 700 mm) with percentage of reinforcement varying from 0.54 to 1.63% which commensurate with existing Codal provisions of IS:456-2000 for flexural member. The effect of confinement is considered in this study. The experimental results are verified by using 3D finite element techniques.

  4. A cohort study using pulmonary function tests and x-ray examination in toner-handling workers: cross-sectional and longitudinal analyses from 2003 to 2008.

    Science.gov (United States)

    Kitamura, H; Terunuma, N; Kurosaki, S; Hata, K; Masuda, M; Kochi, T; Yanagi, N; Murase, T; Ogami, A; Higashi, T

    2015-04-01

    This study uses pulmonary function tests and chest x-ray examinations to examine the relationship between toner-handling work and its health effects. The subjects were 1504 male workers in a Japanese toner and photocopier manufacturing company, in the age range from 19 to 50 years in 2003. Personal exposure measurements, pulmonary function tests, chest x-ray examinations, biomarker measurements, and a questionnaire about respiratory symptoms were conducted. The present study reports the results of pulmonary function tests and chest x-ray examinations conducted in the subjects, which includes a cross-sectional study on the toner handling and non-handling workers and a longitudinal study from 2003 to 2008. Few significant findings were suspected to be caused by toner exposure found in pulmonary function indices in both the cross-sectional and longitudinal studies. Any obvious fibrotic findings in chest x-ray findings related to the toner exposure could not be found out. No evidence of adverse effects on pulmonary function indices and chest x-rays was present in the toner-handling workers as compared to the nonspecifically exposed workers. Although the toner exposure concentration is quite low in the current well-controlled working environment, even among the toner-handling workers, we would like to continue this study in the future to verify the toner exposure health effects. © The Author(s) 2014.

  5. Multi-ethnic perspective of uptake of HIV testing and HIV-related stigma: a cross-sectional population-based study.

    Science.gov (United States)

    Wong, Li Ping

    2013-01-01

    The objective of this study was to identify demographic characteristics and correlates of the uptake of HIV testing, willingness to be tested and perceived HIV-related stigma of Malaysian lay public. A cross-sectional computer-assisted telephone interview survey of a representative sample of multiracial Malaysians aged 18 years and above was conducted between December and July 2011. The survey collected information on demographics, knowledge about HIV transmission and religious beliefs on attitudes to HIV/AIDS. A total of 2271 households were successfully interviewed. The response rate was 48.65%. The HIV transmission knowledge score ranged from 0 to 15 (mean =10.56; SD±2.42). Three of the most common misconceptions about HIV transmission were mosquito bite (42.8%), eating in a restaurant where the cook is HIV positive (20.4%) and using a public toilet (20.1%). Only 20.6% reported ever having been tested for HIV, 49.1% reported a willingness to be tested for HIV and 30.3% had no intention of getting an HIV test. Low-risk perception (63.7%) constitutes a major barrier to HIV testing. Being Malay and Chinese (relative to Indian) were the strongest predictors of low-risk perception. Other significant predictors of low-risk perception were being male, being married and living in an urban locality. Perceived self-stigma if tested positive for HIV was prevalent (78.8%). Multivariate findings showed that being female, Malay, low income, living in rural localities and public stigma were significant correlates of self-stigma. These findings warrant interventions to reduce the disproportionate HIV transmission misconception, barriers to HIV testing and stigma and discriminative attitudes to involve considerations of sociocultural economic and demographic characteristics.

  6. Assessment of Axial Behavior of Circular HPFRCC Members Externally Confined with FRP Sheets

    Directory of Open Access Journals (Sweden)

    Ugur Demir

    2018-01-01

    Full Text Available The aim of this paper is to identify the axial behavior characteristics of FRP (fiber reinforced polymer confined circular HPFRCC (high performance fiber reinforced cementitious composite members under compression. The test program comprised of 24 circular specimens with an average compressive strength of 102.7 MPa, including 21 carbon FRP (CFRP confined (2, 4, 6, 8 and 10 layers and three unconfined specimens. Transverse confinement generated by external FRP sheets resulted with a remarkable enhancement in axial strength and deformability, which is extremely important to resist seismic actions. The higher was the thickness of FRP confinement, the larger was the ultimate strain (εcu and peak compressive strength (f′cc of externally confined HPFRCC. When compared to FRP confined conventional concrete, different axial and lateral deformation characteristics were seen in FRP jacketed HPFRCC members. Higher strength and steel fiber presence in HPFRCC limited the lateral deformations which resulted with reduced strain efficiency with respect to conventional concrete. After presenting the experimental work, performance and accuracy of several available models proposed for predicting the axial behavior of FRP jacketed concrete were evaluated in a comparative manner.

  7. Burnout experiments with 6 x 6, 8 x 8 and 7 x 7 rod bundle test sections using freon as model fluid

    International Nuclear Information System (INIS)

    Fulfs, H.; Katsaounis, A.; Minden, C.v.

    1976-01-01

    This paper reports on burnout experiments at staedy state condition using Freon12 as model fluid. The experiments were carried out with three test sections with 6 x 6, 8 x 8 and 7 x 7 rod bundles. The axial flux distribution of the rods is either constant or reactor like. The transformed measured points using STEVENS and BOURE scaling factors to equivalent water conditions respectively, were compared to the burnout correlation W3 using the reactor layout program DYNAMIT. The DYNAMIT code is a thermohydraulic lay-out reactor program without consideration of mixing flow between the subchannels. (orig.) [de

  8. The impact of a chlamydia education program on practice nurse's knowledge and attitudes in relation to chlamydia testing: a cross-sectional survey.

    Science.gov (United States)

    Lorch, Rebecca; Guy, Rebecca; Temple-Smith, Meredith; Vaisey, Alaina; Wood, Anna; Ford, Belinda; Murray, Carolyn; Bourne, Chris; Tomnay, Jane; Hocking, Jane; ACCEPt Consortium, On Behalf Of The

    2016-02-01

    Background We aimed to determine the impact of a chlamydia (Chlamydia trachomatis) education program on the knowledge of and attitudes towards chlamydia testing of practice nurses (PNs). A cross-sectional survey was conducted at baseline and 6-12 months following recruitment with PNs in the Australian Chlamydia Control Effectiveness Pilot. Likert scales were analysed as continuous variables (scores), and t-tests were used to assess changes in mean scores between survey rounds and groups. Of the 72 PNs who completed both surveys, 42 received education. Epidemiology knowledge scores increased significantly between surveys in the education group (Ptesting scenarios (P=0.01) and retesting following treatment (Ptesting scores improved over time in the education group (P=0.03), with PNs more likely to want increased involvement in chlamydia testing (Ptesting between surveys was higher in the education group (P=0.05). Barriers to chlamydia testing scores also increased in the education group (P=0.03), with change in barriers greater in the education vs the non-education group (P=0.03). The education program led to improved knowledge and attitudes to chlamydia, and could be made available to PNs working in general practice. Future analyses will determine if the education program plus other initiatives can increase testing rates.

  9. NON-LINEAR ANALYSIS OF EFFECT OF CONFINEMENT REGIONS ON MOMENT CURVATURE BEHAVIOR OF SHEAR WALL (THEORETICAL STUDY

    Directory of Open Access Journals (Sweden)

    Şevket Murat ŞENEL

    2002-02-01

    Full Text Available Computer program which investigates the effectiveness of confinement regions of shear walls was developed.Specimens which have unique web reinforcement and different confinement regions were analyzed by using this computer program. Data needed for theoratical computations were obtained by tensile testing of steel rods and by concrete specimen tests. Mander Method was applied to reflect confined concrete behavior. Strain hardening behavior of steel was included in computations. Effect of stirrup spacing and hook reinforcement was introduced together and seperately to understand the moment-curvature response of specimens.

  10. Structural behavior of supercritical fluids under confinement

    Science.gov (United States)

    Ghosh, Kanka; Krishnamurthy, C. V.

    2018-01-01

    The existence of the Frenkel line in the supercritical regime of a Lennard-Jones (LJ) fluid shown through molecular dynamics (MD) simulations initially and later corroborated by experiments on argon opens up possibilities of understanding the structure and dynamics of supercritical fluids in general and of the Frenkel line in particular. The location of the Frenkel line, which demarcates two distinct physical states, liquidlike and gaslike within the supercritical regime, has been established through MD simulations of the velocity autocorrelation (VACF) and radial distribution function (RDF). We, in this article, explore the changes in the structural features of supercritical LJ fluid under partial confinement using atomistic walls. The study is carried out across the Frenkel line through a series of MD simulations considering a set of thermodynamics states in the supercritical regime (P =5000 bar, 240 K ≤T ≤1500 K ) of argon well above the critical point. Confinement is partial, with atomistic walls located normal to z and extending to "infinity" along the x and y directions. In the "liquidlike" regime of the supercritical phase, particles are found to be distributed in distinct layers along the z axis with layer spacing less than one atomic diameter and the lateral RDF showing amorphous-like structure for specific spacings (packing frustration) and non-amorphous-like structure for other spacings. Increasing the rigidity of the atomistic walls is found to lead to stronger layering and increased structural order. For confinement with reflective walls, layers are found to form with one atomic diameter spacing and the lateral RDF showing close-packed structure for the smaller confinements. Translational order parameter and excess entropy assessment confirms the ordering taking place for atomistic wall and reflective wall confinements. In the "gaslike" regime of the supercritical phase, particle distribution along the spacing and the lateral RDF exhibit features

  11. Prevalence and Correlates of HIV Testing among Young People Enrolled in Non-Formal Education Centers in Urban Chiang Mai, Thailand: A Cross-Sectional Study.

    Directory of Open Access Journals (Sweden)

    Patou Masika Musumari

    Full Text Available HIV testing is the gateway to HIV prevention, treatment, and care. Despite the established vulnerability of young Thai people to HIV infection, studies examining the prevalence and correlates of HIV testing among the general population of Thai youth are still very limited. This study investigates socio-demographic, behavioral, and psychosocial factors associated with HIV testing among young Thai people enrolled in Non-formal Education Centers (NFEC in urban Chiang Mai, Northern Thailand.This was a cross-sectional quantitative study conducted among young unmarried Thai youth--between the ages of 15 and 24--who were enrolled in NFEC in urban Chiang Mai. Multiple logistic regressions were used to identify correlates of "ever tested for HIV" among the sexually active participants.Of the 295 sexually active participants, 27.3% reported "ever tested for HIV;" 65.4% "did not consistently use condom;" and 61.7% "had at least 2 lifetime partners." We found that "self-efficacy" (AOR, 4.92; CI, 1.22-19.73; "perception that it is easy to find a location nearby to test for HIV" (AOR, 4.67; CI, 1.21-18.06; "having at least 2 lifetime sexual partners" (AOR, 2.05; CI, 1.09-3.85; and "ever been pregnant or made someone pregnant" (AOR, 4.06; CI, 2.69-9.15; were associated with increased odds of having ever been tested. On the other hand, "fear of HIV test results" (AOR, 0.21; CI, 0.08-0.57 was associated with lower odds of ever having been tested for HIV.The main finding is that a substantially high proportion of Thai youth is engaged in risky sexual behaviors--yet reports low rates of ever having been tested for HIV. This highlights an urgent need to develop appropriate interventions--based on the identified correlates of HIV testing. There is also an urgent need to enhance HIV testing and to promote safer sexual behaviors among young Thai people--particularly those who are out-of-school.

  12. Experimental Study of Confined Low-, Medium- and High-Strength Concrete Subjected to Concentric Compression

    Directory of Open Access Journals (Sweden)

    Antonius

    2012-11-01

    Full Text Available An experimental study of 23 low-, medium- and high-strength concrete columns is presented in this paper. Square-confined concrete columns without longitudinal reinforcement were designed, and tested under concentric axial compression. The columns were made of concrete with a compressive strength ranging between 30 MPa and 70 MPa. The test parameters in the study are concrete compressive strengths and confining steel properties, i.e. spacing, volumetric ratios and configurations. The effects of these parameters on the strength and ductility of square-confined concrete were evaluated. Of the specimens tested in this study, the columns made with higher-strength concrete produced less strength enhancement and ductility than those with lower-strength concrete. The steel configurations were found to have an important role in governing the strength and ductility of the confined high-strength concrete. Moreover, several models of strength enhancement for confined concrete available in the literature turned out to be quite accurate in predicting the experimental results.

  13. Monotonic and cyclic bond behavior of confined concrete using NiTiNb SMA wires

    International Nuclear Information System (INIS)

    Choi, Eunsoo; Chung, Young-Soo; Kim, Yeon-Wook; Kim, Joo-Woo

    2011-01-01

    This study conducts bond tests of reinforced concrete confined by shape memory alloy (SMA) wires which provide active and passive confinement of concrete. This study uses NiTiNb SMA which usually shows wide temperature hysteresis; this is a good advantage for the application of shape memory effects. The aims of this study are to investigate the behavior of SMA wire under residual stress and the performance of SMA wire jackets in improving bond behavior through monotonic-loading tests. This study also conducts cyclic bond tests and analyzes cyclic bond behavior. The use of SMA wire jackets transfers the bond failure from splitting to pull-out mode and satisfactorily increases bond strength and ductile behavior. The active confinement provided by the SMA plays a major role in providing external pressure on the concrete because the developed passive confinement is much smaller than the active confinement. For cyclic behavior, slip and circumferential strain are recovered more with larger bond stress. This recovery of slip and circumferential strain are mainly due to the external pressure of the SMA wires since cracked concrete cannot provide any elastic recovery

  14. Modeling and numerical simulation of the dynamics of nanoparticles applied to free and confined atmospheres

    International Nuclear Information System (INIS)

    Devilliers, Marion

    2012-01-01

    It is necessary to adapt existing models in order to simulate the number concentration, and correctly account for nanoparticles, in both free and confined atmospheres. A model of particle dynamics capable of following accurately the number as well as the mass concentration of particles, with an optimal calculation time, has been developed. The dynamics of particles depends on various processes, the most important ones being condensation/evaporation, followed by nucleation, coagulation, and deposition phenomena. These processes are well-known for fine and coarse particles, but some additional phenomena must be taken into account when applied to nanoparticles, such as the Kelvin effect for condensation/evaporation and the van der Waals forces for coagulation. This work focused first on condensation/evaporation, which is the most numerically challenging process. Particles were assumed to be of spherical shape. The Kelvin effect has been taken into account as it becomes significant for particles with diameter below 50 nm. The numerical schemes are based on a sectional approach: the particle size range is discretized in sections characterized by a representative diameter. A redistribution algorithm is used, after condensation/ evaporation occurred, in order to keep the representative diameter between the boundaries of the section. The redistribution can be conducted in terms of mass or number. The key point in such algorithms is to choose which quantity has to be redistributed over the fixed sections. We have developed a hybrid algorithm that redistributes the relevant quantity for each section. This new approach has been tested and shows significant improvements with respect to most existing models over a wide range of conditions. The process of coagulation for nanoparticles has also been solved with a sectional approach. Coagulation is monitored by the Brownian motion of nanoparticles. This approach is shown to be more efficient if the coagulation rate is evaluated

  15. The Effect of Test Taking Strategy Instruction on Iranian High School Students’ Performance on English Section of the University Entrance Examination and Their Attitude towards Using These Strategies

    Directory of Open Access Journals (Sweden)

    Fatemeh Takallou

    2015-11-01

    Full Text Available This paper reports on a study that investigated the effect of teaching test-taking strategies on Iranian high school students’ performance on English section of the National University Entrance Examination (Konkoor. To do so, 273 male and female high school students participated in a workshop that lasted for four sessions. The participants were randomly divided into an experimental and a control group. In the beginning of the workshop, participants received a demographic questionnaire to see if they had taken part in a similar test-taking class which resulted in excluding some students from the groups. The groups were also homogenized regarding their language proficiency level by administering Oxford Placement Test (OPT. Therefore, 260 participants were left for the main study. Then, experimental group participated in the test-taking strategy workshop and control group worked on the previous samples of Konkoor examinations without any reference to test-taking strategies. At the end of the workshop, the attitude questionnaire was run in the experimental group to compile the group’s opinions about the treatment.  One month later, the students of both groups took Konkoor. The data were analyzed using an independent-samples t-test. The learners’ responses to the attitude questionnaire were also analyzed quantitatively. The findings of this study indicated that Iranian high school students in the experimental group outperformed the control group on their Konkoor exam. Moreover, they had positive attitudes towards teaching and learning test-taking strategies. This study suggests that integrating such strategies in the teaching curriculum could be beneficial for the students.

  16. Simulation and low velocity impact testing on confined explosives

    NARCIS (Netherlands)

    Scholtes, J.H.G.; Verbeek, H.J.

    2010-01-01

    TNO Defence Security and Safety, performs in depth research in energetic material responses to several Insensitive Munitions (IM) stimuli like cook-off, bullet-fragment impact and shaped charge impact. The response of energetic materials to these stimuli depends strongly on the properties of these

  17. System and method of operating toroidal magnetic confinement devices

    Science.gov (United States)

    Chance, M.S.; Jardin, S.C.; Stix, T.H.; Grimm, R.C.; Manickam, J.; Okabayashi, M.

    1984-08-30

    This invention pertains to methods and arrangements for attaining high beta values in plasma confinement devices. More specifically, this invention pertains to methods for accessing the second stability region of operation in toroidal magnetic confinement devices.

  18. Multiscale confining dynamics from holographic RG flows

    Science.gov (United States)

    Elander, Daniel; Faedo, Anton F.; Hoyos, Carlos; Mateos, David; Piai, Maurizio

    2014-05-01

    We consider renormalization group flows between conformal field theories in five (six) dimensions with a string (M-theory) dual. By compactifying on a circle (torus) with appropriate boundary conditions, we obtain continuous families of confining fourdimensional theories parametrized by the ratio Λflow/ΛQCD, with Λflow the scale at which the flow between fixed points takes place and ΛQCD the confinement scale. We construct the dual geometries explicitly and compute the spectrum of scalar bound states (glueballs). We find a `universal' subset of states common to all the models. We comment on the modifications of these models, and the corresponding fine-tuning, required for a parametrically light `dilaton' state to be present. We also comment on some aspects of these theories as probed by extended objects such as strings and branes.

  19. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    Energy Technology Data Exchange (ETDEWEB)

    FISHER,R.K

    2004-04-01

    Three new approaches to obtain information on the confined fast alphas in International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by {approx}140 microns per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER.

  20. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    International Nuclear Information System (INIS)

    FISHER, R.K.

    2004-01-01

    Three new approaches to obtain information on the confined fast alphas in International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by ∼140 microns per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER

  1. Inertial confinement: concept and early history

    International Nuclear Information System (INIS)

    Linhart, J.G.

    1986-01-01

    The concept of inertial confinement is linked to the general theme of energy compression and staging. It is shown how it arose from the ideas and experiments on dynamic pinches towards the end of the fifties and how the important key concept of a linear was further developed during the sixties. THe various attempts at driving linears to speeds in excess of 1 cm/μs are reviewed in chronological order, mentioning the important impetus given to this field by the consideration of laser as a driver. It is concluded that the field of inertial confinement fusion (ICF) is becoming ever richer in possibilities, and the understanding of the physics of high-energy density has reached now a satisfactory level

  2. Influence of confining layers' heterogeneity on the barometric response functions in semi-confined aquifers

    Science.gov (United States)

    Redaelli, Marco; Perulero Serrano, Raul

    2017-04-01

    It has been shown that Barometric Response Functions (BRFs) can provide a useful tool for detecting the occurrence of highly conducive bodies which span across aquifer confining layers and can potentially give rise to pathways for pollutant migration (Hussein et al 2013, Odling et al 2015). Analytical models employed to estimate BRFs from geological system properties assume homogeneity within the aquifer and its confining layer. These assumptions are rarely satisfied in practice. Our study focusses on the impact on predicted BRFs of heterogeneous distribution of high conductivity geomaterials within the confining layer. The work is grounded on a suite of three-dimensional, transient numerical computations of groundwater flow in a confining layer-aquifer system for i) a perfectly homogeneous two-layer setting where a single highly conducive block is fully penetrating the confining layer and ii) a heterogeneous two-layer system where hydraulic conductivity in the confining layer is modelled as a stochastic process. Our numerical results are interpreted through a comparison against those associated with an analytical model which assumes system homogeneity. Monitoring points located in the middle of the modelled aquifer domain, mimicking screened boreholes in field conditions, are used to extract water level records. The output is used to obtain the corresponding BRFs (in terms of gain and phase components) and compared vis-a-vis the selected analytical solution. The results show a wide variety of BRF responses, especially in the gain component, which vary from almost confined to unconfined scenarios. Our simulations show that the BRFs are a viable tool to improve understanding of the degree of spatial continuity within low permeability heterogeneous geological materials such as glacial till which is frequently found overlying water bearing units across the UK and other localities worldwide. As such, it has the potential to improve groundwater vulnerability assessment

  3. Triaxial behaviour of a micro-concrete complete stress-strain curves for confining pressures ranging from 0 to 100 MPa

    International Nuclear Information System (INIS)

    Jamet, P.; Millard, A.; Nahas, G.

    1984-05-01

    A series of triaxial tests has been performed on micro-concrete cylinders. The specimens have been strained with a constant displacement rate, up to a deformation of about 10%. Two different domains were distinguihed. For low confining pressures strain softening is observed, the behaviour of the material becomes ductile for high confining pressures. Continuous measurement of the volume of fluid which had to be injected or withdrawn from the cell, to keep the confining pressure constant during the test, allowed to obtain data, concerning the overall lateral deformations of the specimens. Some specimens were also subjected to successive loadings with different confining pressures, in order to study the influence of stress path

  4. Yukawa particles in a confining potential

    Energy Technology Data Exchange (ETDEWEB)

    Girotto, Matheus, E-mail: matheus.girotto@ufrgs.br; Levin, Yan, E-mail: levin@if.ufrgs.br [Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS (Brazil); Santos, Alexandre P. dos, E-mail: alexandreps@ufcspa.edu.br [Departamento de Educação e Informação em Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, 90050-170, Porto Alegre, RS (Brazil); Departamento de Física, Universidade Federal de Santa Catarina, 88040-900, Florianópolis, Santa Catarina (Brazil); Colla, Thiago, E-mail: thiago.colla@ufrgs.br [Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna (Austria)

    2014-07-07

    We study the density distribution of repulsive Yukawa particles confined by an external potential. In the weak coupling limit, we show that the mean-field theory is able to accurately account for the particle distribution. In the strong coupling limit, the correlations between the particles become important and the mean-field theory fails. For strongly correlated systems, we construct a density functional theory which provides an excellent description of the particle distribution, without any adjustable parameters.

  5. Confinement scaling and ignition in tokamaks

    International Nuclear Information System (INIS)

    Perkins, F.W.; Sun, Y.C.

    1985-10-01

    A drift wave turbulence model is used to compute the scaling and magnitude of central electron temperature and confinement time of tokamak plasmas. The results are in accord with experiment. Application to ignition experiments shows that high density (1 to 2) . 10 15 cm -3 , high field, B/sub T/ > 10 T, but low temperature T approx. 6 keV constitute the optimum path to ignition

  6. Twenty years of ''Nuclear Fusion''. Inertial confinement

    International Nuclear Information System (INIS)

    Yamanaka, C.

    1980-01-01

    Inertial confinement (ICF) fusion research is directed towards demonstrating the feasibility of very rapidly heating and compressing small pellets of suitable fuel until conditions exist where thermonuclear fusion can occur and useful amounts of power can be produced. Major problems which have to be solved are the following: 1) pellet design based on driver-plasma coupling; 2) the technology of energy drivers; 3) feasibility of ICF reactor systems

  7. A transport model with color confinement

    International Nuclear Information System (INIS)

    Loh, S.

    1997-01-01

    First the mostly important properties of QCD are dealt with. It is made plausible, how the QCD vacuum generates a screening of color charges and is by this responsible for the quark confinement in color singlets. in the following the behaviour of classical color charges and color fields is studied and it is concluded that by this approximation, the neglection of quantum-mechanical fluctuation, the quark confinement cannot be explained, because the mean-field approximation leads to a screening of the color charges. Motivated by this result the Friedberg-Lee soliton model is presented, in which the the color confinement and all further nonperturbative QCD effects are phenomenologically modelled by means of a scalar field. Thereafter a derivation of the transport equations for quarks in the framework of the Wigner-function is presented. An extension of the equation to the Friedberg-Lee model is explained. As results the ground-state properties of the model are studied. Mesonic and baryonic ground-state solutions (soliton solutions) of the equations are constructed, whereby the constituents are both light quarks and heavy quarks. Furthermore the color coupling constant of QCD is fixed by means of the string tension by dynamical separation of the quarks of the meson. The flux tubes formed dynamically in this way are applied, in order to study the interaction of two strings and to calculate a string-string potential. Excited states of the meson (isovectorial modes) are presented as well as the influence of the color confinement on the quark motion. Finally the dynamical formation and the break-up of a string by the production of light and heavy quark pairs is described

  8. Theoretical aspects of energy confinement in spheromaks

    International Nuclear Information System (INIS)

    Fowler, T.K.

    1994-01-01

    It is shown that, despite the poor global energy confinement observed in spheromak experiments to date, the long-term prospects may be favorable as spheromaks are scaled to larger size and higher temperatures. The present performance is traced to excessive magnetic energy loss at the edge compared to tokamaks and heat transport due to magnetic fluctuations, both of which should scale away as the temperature increases

  9. Charm production and the confining force field

    International Nuclear Information System (INIS)

    Andersson, B.; Bengtsson, H.-U.; Gustafson, G.

    1983-03-01

    We show that charm production at SPS energies can be understood simply from O(α 2 sub (s)) QCD processes when combined with fragmentation of the colour fields stretched by the final state partons. The tension of the confining force field responsible for particle production is found to pull the charmed particles away from the reaction centre, giving rise to a harder x sub (F)-spectrum than would be expected from the bare QCD matrix elements. (Authors)

  10. Target support for inertial confinement fusion

    International Nuclear Information System (INIS)

    Schultz, K.R.

    1995-08-01

    General Atomics (GA) plays an important industrial support role for the US Inertial Confinement Fusion (ICF) program in the area of target technology. This includes three major activities: target fabrication support, target handling systems development, and target chamber design. The work includes target fabrication for existing ICF experiments, target and target system development for future experiments, and target research and target chamber design for experiments on future machines, such as the National Ignition Facility (NIF)

  11. Mesoscale simulations of confined Nafion thin films

    OpenAIRE

    Vanya, Peter; Sharman, Jonathan; Elliott, James A.

    2017-01-01

    The morphology and transport properties of thin films of the ionomer Nafion, with thicknesses on the order of the bulk cluster size, have been investigated as a model system to explain the anomalous behaviour of catalyst/electrode-polymer interfaces in membrane-electrode assemblies. We have employed dissipative particle dynamics (DPD) to investigate the interaction of water and fluorocarbon chains with carbon and quartz as confining materials for a wide range of operational water contents and...

  12. Mesoscale simulations of confined Nafion thin films

    OpenAIRE

    Vanya, Peter; Sharman, J; Elliott, James Arthur

    2017-01-01

    The morphology and transport properties of thin films of the ionomer Nafion, with thicknesses on the order of the bulk cluster size, have been investigated as a model system to explain the anomalous behaviour of catalyst/electrode-polymer interfaces in membrane electrode assemblies. We have employed dissipative particle dynamics (DPD) to investigate the interaction of water and fluorocarbon chains with carbon and quartz as confining materials for a wide range of operational water contents and...

  13. Spectral confinement and current for atoms in strong magnetic fields

    DEFF Research Database (Denmark)

    Fournais, Søren

    2007-01-01

    e study confinement of the ground state of atoms in strong magnetic fields to different subspaces related to the lowest Landau band. Using the results on confinement we can calculate the quantum current in the entire semiclassical region B<3......e study confinement of the ground state of atoms in strong magnetic fields to different subspaces related to the lowest Landau band. Using the results on confinement we can calculate the quantum current in the entire semiclassical region B

  14. Confinement of nonneutral plasma in unconventional geometries

    International Nuclear Information System (INIS)

    Turner, L.

    1990-01-01

    Our interest in efficient storage of cold, nonneutral plasma has been motivated by the elegant studies on cryogenic nonneutral electron plasmas at UCSD and by the remarkable results obtained from the laser-cooled ion plasmas at the NIST, Boulder, Colorado. Also motivating our study is the perceived need to develop the most expedient means of storing antimatter, whether it be antiprotons for gravitational studies or positrons for a variety of physics experiments and diagnostic purposes. One of the most explored technologies of confining nonneutral plasmas is the Penning trap. The maximum number density of cold nonneutral plasma that can be stored in such a trap is B 2 /2μ 0 mc 2 , in which B 2 /2μ 0 is the (homogeneous) magnetic energy density and mc 2 is the rest energy of the stored charges. In this paper, we shall present a synopsis of the results of our theoretical exploration of the effect on this hydrostatic limit, the so-called ''Brillouin'' limit, of altering the geometry of the confining vacuum magnetic field while maintaining the field's azimuthal symmetry. In particular, we shall analyze equilibrium confinement by, first, a poloidal magnetic field, B 4 (r,z)r + B z (r,z)z, and second, a toroidal magnetic field, along with the concomitant electrostatic fields

  15. Plasma confinement studies in open systems

    Science.gov (United States)

    Yatsu, Kiyoshi

    1999-03-01

    Studies in open systems in the world are reviewed from viewpoints of the potential confinement and magnetohydrodynamic (MHD) stability. The tandem mirror GAMMA 10 has shown the potential confinement of a high-ion-temperature plasma from an analysis of the time evolution of end-loss ion current and end-loss ion energy distributions. The central cell density was increased by 50% by the potential confinement. In the HIEI tandem mirror H-mode-like phenomena were observed with an increase in density and diamagnetic signal in a limiter biasing experiment. Potential formation phenomena in plasmas are studied by 0741-3335/41/3A/024/img1-like Upgrade under different magnetic field configurations and plasma conditions. The fully axisymmetric tandem mirror AMBAL-M is under construction and its end mirror system has been assembled. Heating experiments of a plasma gun produced plasma by neutral beam injection and ICRF heating are in progress. The gas dynamic trap (GDT) experiment has successfully produced an MHD-stable high-temperature, high-density plasma. In GOL-3-II, a high-density plasma with several 100 eV temperature is created by powerful relativistic electron beam injection. Construction of HANBIT has been completed and experiments on plasma production and ICRF heating have begun.

  16. Dynamics of Hyperbranched Polymers under Confinement

    Science.gov (United States)

    Androulaki, Krystallenia; Chrissopoulou, Kiriaki; Anastasiadis, Spiros H.; Prevosto, Daniele; Labardi, Massimiliano

    2015-03-01

    The effect of severe confinement on the dynamics of three different generations of hyperbranched polyesters (Boltorns) is investigated by Dielectric Spectroscopy. The polymers are intercalated within the galleries of natural Na+-MMT, thus, forming 1nm polymer films confined between solid walls. The Tg's of the polymers determined by DSC show a clear dependence on the generation whereas the transition is completely suppressed when all the polymer chains are intercalated. The dynamic investigation of the bulk polymers reveals two sub-Tg processes, with similar behavior for the three polymers with the segmental relaxation observed above the Tg of each. For the nanocomposites, where all polymers are severely confined, the dynamics show significant differences compared to that of the bulk polymers. The sub-Tg processes are similar for the three generations but significantly faster and with weaker temperature dependence than those in the bulk. The segmental process appears at temperatures below the bulk polymer Tg, it exhibits an Arrhenius temperature dependence and shows differences for the three generations. A slow process that appears at higher temperatures is due to interfacial polarization. Co-financed by the EU and Greek funds through the Operational Program ``Education and Lifelong Learning'' of the NSRF-Research Funding Program: THALES-Investing in knowledge society through the Eur. Social Fund (MIS 377278) and COST Action MP0902-COINAPO.

  17. Quantum Confined Semiconductors for High Efficiency Photovoltaics

    Science.gov (United States)

    Beard, Matthew

    2014-03-01

    Semiconductor nanostructures, where at least one dimension is small enough to produce quantum confinement effects, provide new pathways for controlling energy flow and therefore have the potential to increase the efficiency of the primary photon-to-free energy conversion step. In this discussion, I will present the current status of research efforts towards utilizing the unique properties of colloidal quantum dots (NCs confined in three dimensions) in prototype solar cells and demonstrate that these unique systems have the potential to bypass the Shockley-Queisser single-junction limit for solar photon conversion. The solar cells are constructed using a low temperature solution based deposition of PbS or PbSe QDs as the absorber layer. Different chemical treatments of the QD layer are employed in order to obtain good electrical communication while maintaining the quantum-confined properties of the QDs. We have characterized the transport and carrier dynamics using a transient absorption, time-resolved THz, and temperature-dependent photoluminescence. I will discuss the interplay between carrier generation, recombination, and mobility within the QD layers. A unique aspect of our devices is that the QDs exhibit multiple exciton generation with an efficiency that is ~ 2 to 3 times greater than the parental bulk semiconductor.

  18. Chemical reactions confined within carbon nanotubes.

    Science.gov (United States)

    Miners, Scott A; Rance, Graham A; Khlobystov, Andrei N

    2016-08-22

    In this critical review, we survey the wide range of chemical reactions that have been confined within carbon nanotubes, particularly emphasising how the pairwise interactions between the catalysts, reactants, transition states and products of a particular molecular transformation with the host nanotube can be used to control the yields and distributions of products of chemical reactions. We demonstrate that nanoscale confinement within carbon nanotubes enables the control of catalyst activity, morphology and stability, influences the local concentration of reactants and products thus affecting equilibria, rates and selectivity, pre-arranges the reactants for desired reactions and alters the relative stability of isomeric products. We critically evaluate the relative advantages and disadvantages of the confinement of chemical reactions inside carbon nanotubes from a chemical perspective and describe how further developments in the controlled synthesis of carbon nanotubes and the incorporation of multifunctionality are essential for the development of this ever-expanding field, ultimately leading to the effective control of the pathways of chemical reactions through the rational design of multi-functional carbon nanoreactors.

  19. Water nanodroplets confined in zeolite pores.

    Science.gov (United States)

    Coudert, François-Xavier; Cailliez, Fabien; Vuilleumier, Rodolphe; Fuchs, Alain H; Boutin, Anne

    2009-01-01

    We provide a comprehensive depiction of the behaviour of a nanodroplet of approximately equal to 20 water molecules confined in the pores of a series of 3D-connected isostructural zeolites with varying acidity, by means of molecular simulations. Both grand canonical Monte Carlo simulations using classical interatomic forcefields and first-principles Car-Parrinello molecular dynamics were used in order to characterise the behaviour of confined water by computing a range of properties, from thermodynamic quantities to electronic properties such as dipole moment, including structural and dynamical information. From the thermodynamic point of view, we have identified the all-silica zeolite as hydrophobic, and the cationic zeolites as hydrophilic; the condensation transition in the first case was demonstrated to be of first order. Furthermore, in-depth analysis of the dynamical and electronic properties of water showed that water in the hydrophobic zeolite behaves as a nanodroplet trying to close its hydrogen-bond network onto itself, with a few short-lived dangling OH groups, while water in hydrophilic zeolites "opens up" to form weak hydrogen bonds with the zeolite oxygen atoms. Finally, the dipole moment of confined water is studied and the contributions of water self-polarisation and the zeolite electric field are discussed.

  20. Status of global energy confinement studies

    International Nuclear Information System (INIS)

    Kaye, S.M.; Bell, M.G.; DeBoo, J.C.; Waltz, R.; Greenwald, M.; Sigmar, D.

    1990-02-01

    Empirical scaling expressions, reflecting the parametric dependence of the L-mode energy confinement time, have been used not only as benchmarks for tokamak operation and theories of energy transport, but for predicting the performance of proposed tokamak devices. Several scaling expressions based on data from small-and medium-sized devices have done well in predicting performance in larger devices, although great uncertainty exists in extrapolating yet farther, into the ignition regime. Several approaches exist for developing higher confidence scaling expressions. These include reducing the statistical uncertainty by identifying and filling in gaps in the present database, making use of more sophisticated statistical techniques, and developing scalings for confinement regimes within which future devices will operate. Confidence in the scaling expressions will be increased still if the expressions can be more directly tied to transport physics theory. This can be done through the use of dimensionless parameters, better describing the edge and core confinement regimes separately, and by incorporating transport models directly into the scaling expressions. 50 refs., 5 figs., 3 tabs

  1. West European magnetic confinement fusion research

    International Nuclear Information System (INIS)

    McKenney, B.L.; McGrain, M.; Hogan, J.T.; Porkolab, M.; Thomassen, K.I.

    1990-01-01

    This report presents a technical assessment and review of the West European program in magnetic confinement fusion by a panel of US scientists and engineers active in fusion research. Findings are based on the scientific and technical literature, on laboratory reports and preprints, and on the personal experiences and collaborations of the panel members. Concerned primarily with developments during the past 10 years, from 1979 to 1989, the report assesses West European fusion research in seven technical areas: tokamak experiments; magnetic confinement technology and engineering; fusion nuclear technology; alternate concepts; theory; fusion computations; and program organization. The main conclusion emerging from the analysis is that West European fusion research has attained a position of leadership in the international fusion program. This distinction reflects in large measure the remarkable achievements of the Joint European Torus (JET). However, West European fusion prominence extends beyond tokamak experimental physics: the program has demonstrated a breadth of skill in fusion science and technology that is not excelled in the international effort. It is expected that the West European primacy in central areas of confinement physics will be maintained or even increased during the early 1990s. The program's maturity and commitment kindle expectations of dramatic West European advances toward the fusion energy goal. For example, achievement of fusion breakeven is expected first in JET, before 1995

  2. Confined Tube Crimp Using Portable Hand Tools

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, Joseph James [Los Alamos National Laboratory; Pereyra, R. A. [LANL Retired; Archuleta, Jeffrey Christopher [Los Alamos National Laboratory; Martinez, Isaac P. [Los Alamos National Laboratory; Nelson, A. M. [MST-16 Summer Student (2007); Allen, Ronald Scott [Los Alamos National Laboratory; Page, R. L. [LANL Retired; Freer, Jerry Eugene [Los Alamos National Laboratory; Dozhier, Nathan Gus [Los Alamos National Laboratory

    2016-04-04

    The Lawrence Radiation Laboratory developed handheld tools that crimp a 1/16 inch OD tube, forming a leak tight seal1 (see Figure 1). The leak tight seal forms by confining the 1/16 inch OD tubing inside a die while applying crimp pressure. Under confined pressure, the tube walls weld at the crimp. The purpose of this study was to determine conditions for fabricating a leak tight tube weld. The equipment was used on a trial-and-error basis, changing the conditions after each attempt until successful welds were fabricated. To better confine the tube, the die faces were polished. Polishing removed a few thousandths of an inch from the die face, resulting in a tighter grip on the tubing wall. Using detergent in an ultrasonic bath, the tubing was cleaned. Also, the time under crimp pressure was increased to 30 seconds. With these modifications, acceptable cold welds were fabricated. After setting the conditions for an acceptable cold weld, the tube was TIG welded across the crimped face.

  3. Evaporation rate of water in hydrophobic confinement.

    Science.gov (United States)

    Sharma, Sumit; Debenedetti, Pablo G

    2012-03-20

    The drying of hydrophobic cavities is believed to play an important role in biophysical phenomena such as the folding of globular proteins, the opening and closing of ligand-gated ion channels, and ligand binding to hydrophobic pockets. We use forward flux sampling, a molecular simulation technique, to compute the rate of capillary evaporation of water confined between two hydrophobic surfaces separated by nanoscopic gaps, as a function of gap, surface size, and temperature. Over the range of conditions investigated (gaps between 9 and 14 Å and surface areas between 1 and 9 nm(2)), the free energy barrier to evaporation scales linearly with the gap between hydrophobic surfaces, suggesting that line tension makes the predominant contribution to the free energy barrier. The exponential dependence of the evaporation rate on the gap between confining surfaces causes a 10 order-of-magnitude decrease in the rate when the gap increases from 9 to 14 Å. The computed free energy barriers are of the order of 50 kT and are predominantly enthalpic. Evaporation rates per unit area are found to be two orders of magnitude faster in confinement by the larger (9 nm(2)) than by the smaller (1 nm(2)) surfaces considered here, at otherwise identical conditions. We show that this rate enhancement is a consequence of the dependence of hydrophobic hydration on the size of solvated objects. For sufficiently large surfaces, the critical nucleus for the evaporation process is a gap-spanning vapor tube.

  4. Thermal-hydraulic characteristics inside in-core structure test section (T2) of helium engineering demonstration loop (HENDEL) under loss of forced circulation condition

    International Nuclear Information System (INIS)

    Takada, Shoji; Inagaki, Yoshiyuki; Ioka, Ikuo; Sudo, Yukio

    1995-01-01

    As the results of experimental and analytical works using T 2 test section in HENDEL, the thermal and hydraulic characteristics inside the pressure vessel under loss of forced circulation condition are summarized as follows, (1) Temperatures of side shielding blocks and metallic structures such as a pressure vessel, core restraint mechanism reach their peak temperatures at 15-40 hours after the starting time of natural convection. The temperature transients of components agree with analytical results, comparatively. (2) Pressure difference between cold and hot helium gas becomes close to zero in 6 minutes after the starting time of natural convection due to the leakage flow of helium gas through the graphite blocks. The exchange of hot and cold helium gas through the leakage paths in the CBS graphite blocks are predicted by analytical results. (3) Helium gas pressure decreases after the starting point of natural convection. The reason is considered that hot helium gas is cooled down in the hot gas ducts, helium gas coolers and a helium gas heater with water jacket between T 2 test section and the closed valves of M+A sections in HENDEL. (4) Initial temperatures of the CBS graphite components depend on helium gas pressure because leakage flow of cold helium gas through the CBS increases with helium gas pressure. (5) The elapsed times which temperatures of pressure vessel reach peak temperatures become shorter and the peak temperature decreases as helium gas pressure is higher. The reason is considered that natural convection becomes stronger and the heat transfer coefficients on the CBS and pressure vessel increase as helium gas pressure increases under the natural convection conditions. (author)

  5. Confining continuous manipulations of accelerator beam-line optics

    Directory of Open Access Journals (Sweden)

    Ph. Amstutz

    2017-04-01

    Full Text Available Altering the optics in one section of a linear accelerator beam line will in general cause an alteration of the optics in all downstream sections. In circular accelerators, changing the optical properties of any beam-line element will have an impact on the optical functions throughout the whole machine. In many cases, however, it is desirable to change the optics in a certain beam-line section without disturbing any other parts of the machine. Such a local optics manipulation can be achieved by adjusting a number of additional corrector magnets that restore the initial optics after the manipulated section. In that case, the effect of the manipulation is confined in the region between the manipulated and the correcting beam-line elements. Introducing a manipulation continuously, while the machine is operating, therefore requires continuous correction functions to be applied to the correcting quadrupole magnets. In this paper, we present an approach to calculate such continuous correction functions for six quadrupole magnets by means of a homotopy method. Besides a detailed derivation of the method, we present its application to an algebraic example, as well as its demonstration at the seeding experiment sFLASH at the free-electron laser FLASH located at DESY in Hamburg.

  6. Mechanosensitivity during lower extremity neurodynamic testing is diminished in individuals with Type 2 Diabetes Mellitus and peripheral neuropathy: a cross sectional study

    Directory of Open Access Journals (Sweden)

    Boyd Benjamin S

    2010-08-01

    Full Text Available Abstract Background Type 2 Diabetes Mellitus (T2DM and diabetic symmetrical polyneuropathy (DSP impact multiple modalities of sensation including light touch, temperature, position sense and vibration perception. No study to date has examined the mechanosensitivity of peripheral nerves during limb movement in this population. The objective was to determine the unique effects T2DM and DSP have on nerve mechanosensitivity in the lower extremity. Methods This cross-sectional study included 43 people with T2DM. Straight leg raise neurodynamic tests were performed with ankle plantar flexion (PF/SLR and dorsiflexion (DF/SLR. Hip flexion range of motion (ROM, lower extremity muscle activity and symptom profile, intensity and location were measured at rest, first onset of symptoms (P1 and maximally tolerated symptoms (P2. Results The addition of ankle dorsiflexion during SLR testing reduced the hip flexion ROM by 4.3° ± 6.5° at P1 and by 5.4° ± 4.9° at P2. Individuals in the T2DM group with signs of severe DSP (n = 9 had no difference in hip flexion ROM between PF/SLR and DF/SLR at P1 (1.4° ± 4.2°; paired t-test p = 0.34 or P2 (0.9° ± 2.5°; paired t-test p = 0.31. Movement induced muscle activity was absent during SLR with the exception of the tibialis anterior during DF/SLR testing. Increases in symptom intensity during SLR testing were similar for both PF/SLR and DF/SLR. The addition of ankle dorsiflexion induced more frequent posterior leg symptoms when taken to P2. Conclusions Consistent with previous recommendations in the literature, P1 is an appropriate test end point for SLR neurodynamic testing in people with T2DM. However, our findings suggest that people with T2DM and severe DSP have limited responses to SLR neurodynamic testing, and thus may be at risk for harm from nerve overstretch and the information gathered will be of limited clinical value.

  7. The health beliefs of mothers about preventing cervical cancer and their intention to recommend the Pap test to their daughters: a cross-sectional survey

    Directory of Open Access Journals (Sweden)

    Hae Won Kim

    2016-05-01

    Full Text Available Abstract Background Mothers have a primary role in the prevention of cervical cancer in Korea. This study aimed to determine the awareness and health beliefs of mothers about preventing cervical cancer in their daughters, their intention to recommend the Pap test to their daughters, and the factors influencing this intention. Methods A cross-sectional survey design was employed, and the study enrolled mothers (n = 1,581 of pubescent girls aged 13 to 18 years who were living nationwide in Korea. The six health-beliefs variables related to preventing cervical cancer in their daughters, awareness of the importance of cervical cancer prevention methods, and the intention to recommend the Pap test to daughters were investigated. The impacts of these health beliefs of the mothers and the sociodemographic factors influencing their intention to recommend the Pap test to their daughters were assessed using multiple logistic regression analysis. Results Almost one-quarter (23.7 % of the mothers had talked about the Pap test, 69.2 % were intending to recommend the Pap test to their daughters, and 38.5 % considered that the Pap test could be necessary if their daughters became sexually active. The significant health beliefs influencing the intention to recommend the Pap test were the perceived barriers [odds ratio (OR = 1.47, 95 % confidence interval (95 % CI = 1.03–2.11] and benefits (OR = 2.25, 95 % CI = 1.55–3.25. The significant sociodemographic factors of mothers were their education (OR = 1.52, 95 % CI = 1.08–2.13, their experience of talking about the Pap test with their daughters (OR = 2.11, 95 % CI = 1.23–3.64, their regularity of undergoing the Pap test themselves (OR = 1.98, 95 % CI = 1.30–3.03, and their age when they first underwent the Pap test (OR = 1.60, 95 % CI = 1.43–0.82. Conclusions The mothers perceived HPV vaccination as the most important of the five methods

  8. The health beliefs of mothers about preventing cervical cancer and their intention to recommend the Pap test to their daughters: a cross-sectional survey.

    Science.gov (United States)

    Kim, Hae Won

    2016-05-03

    Mothers have a primary role in the prevention of cervical cancer in Korea. This study aimed to determine the awareness and health beliefs of mothers about preventing cervical cancer in their daughters, their intention to recommend the Pap test to their daughters, and the factors influencing this intention. A cross-sectional survey design was employed, and the study enrolled mothers (n = 1,581) of pubescent girls aged 13 to 18 years who were living nationwide in Korea. The six health-beliefs variables related to preventing cervical cancer in their daughters, awareness of the importance of cervical cancer prevention methods, and the intention to recommend the Pap test to daughters were investigated. The impacts of these health beliefs of the mothers and the sociodemographic factors influencing their intention to recommend the Pap test to their daughters were assessed using multiple logistic regression analysis. Almost one-quarter (23.7 %) of the mothers had talked about the Pap test, 69.2 % were intending to recommend the Pap test to their daughters, and 38.5 % considered that the Pap test could be necessary if their daughters became sexually active. The significant health beliefs influencing the intention to recommend the Pap test were the perceived barriers [odds ratio (OR) = 1.47, 95 % confidence interval (95 % CI) = 1.03-2.11] and benefits (OR = 2.25, 95 % CI = 1.55-3.25). The significant sociodemographic factors of mothers were their education (OR = 1.52, 95 % CI = 1.08-2.13), their experience of talking about the Pap test with their daughters (OR = 2.11, 95 % CI = 1.23-3.64), their regularity of undergoing the Pap test themselves (OR = 1.98, 95 % CI = 1.30-3.03), and their age when they first underwent the Pap test (OR = 1.60, 95 % CI = 1.43-0.82). The mothers perceived HPV vaccination as the most important of the five methods for preventing cervical cancer in their daughters. Mothers perceived the

  9. An Experimental Study of Dynamic Tensile Failure of Rocks Subjected to Hydrostatic Confinement

    Science.gov (United States)

    Wu, Bangbiao; Yao, Wei; Xia, Kaiwen

    2016-10-01

    It is critical to understand the dynamic tensile failure of confined rocks in many rock engineering applications, such as underground blasting in mining projects. To simulate the in situ stress state of underground rocks, a modified split Hopkinson pressure bar system is utilized to load Brazilian disc (BD) samples hydrostatically, and then exert dynamic load to the sample by impacting the striker on the incident bar. The pulse shaper technique is used to generate a slowly rising stress wave to facilitate the dynamic force balance in the tests. Five groups of Laurentian granite BD samples (with static BD tensile strength of 12.8 MPa) under the hydrostatic confinement of 0, 5, 10, 15, and 20 MPa were tested with different loading rates. The result shows that the dynamic tensile strength increases with the hydrostatic confining pressure. It is also observed that under the same hydrostatic pressure, the dynamic tensile strength increases with the loading rate, revealing the so-called rate dependency for engineering materials. Furthermore, the increment of the tensile strength decreases with the hydrostatic confinement, which resembles the static tensile behavior of rock under confining pressure, as reported in the literature. The recovered samples are examined using X-ray micro-computed tomography method and the observed crack pattern is consistent with the experimental result.

  10. Coexistence of Multilayered Phases of Confined Water: The Importance of Flexible Confining Surfaces.

    Science.gov (United States)

    Ruiz Pestana, Luis; Felberg, Lisa E; Head-Gordon, Teresa

    2018-01-23

    Flexible nanoscale confinement is critical to understanding the role that bending fluctuations play on biological processes where soft interfaces are ubiquitous or to exploit confinement effects in engineered systems where inherently flexible 2D materials are pervasively employed. Here, using molecular dynamics simulations, we compare the phase behavior of water confined between flexible and rigid graphene sheets as a function of the in-plane density, ρ 2D . We find that both cases show commensurate mono-, bi-, and trilayered states; however, the water phase in those states and the transitions between them are qualitatively different for the rigid and flexible cases. The rigid systems exhibit discontinuous transitions between an (n)-layer and an (n+1)-layer state at particular values of ρ 2D , whereas under flexible confinement, the graphene sheets bend to accommodate an (n)-layer and an (n+1)-layer state coexisting in equilibrium at the same density. We show that the flexible walls introduce a very different sequence of ice phases and their phase coexistence with vapor and liquid phases than that observed with rigid walls. We discuss the applicability of these results to real experimental systems to shed light on the role of flexible confinement and its interplay with commensurability effects.

  11. History of Solitary Confinement Is Associated with Post-Traumatic Stress Disorder Symptoms among Individuals Recently Released from Prison.

    Science.gov (United States)

    Hagan, Brian O; Wang, Emily A; Aminawung, Jenerius A; Albizu-Garcia, Carmen E; Zaller, Nickolas; Nyamu, Sylviah; Shavit, Shira; Deluca, Joseph; Fox, Aaron D

    2018-04-01

    This study assessed the relationship between solitary confinement and post-traumatic stress disorder (PTSD) symptoms in a cohort of recently released former prisoners. The cross-sectional design utilized baseline data from the Transitions Clinic Network, a multi-site prospective longitudinal cohort study of post-incarceration medical care. Our main independent variable was self-reported solitary confinement during the participants' most recent incarceration; the dependent variable was the presence of PTSD symptoms determined by primary care (PC)-PTSD screening when participants initiated primary care in the community. We used multivariable logistic regression to adjust for potential confounders, such as prior mental health conditions, age, and gender. Among 119 participants, 43% had a history of solitary confinement and 28% screened positive for PTSD symptoms. Those who reported a history of solitary confinement were more likely to report PTSD symptoms than those without solitary confinement (43 vs. 16%, p history of solitary confinement (OR = 3.93, 95% CI 1.57-9.83) and chronic mental health conditions (OR = 4.04, 95% CI 1.52-10.68) were significantly associated with a positive PTSD screen after adjustment for the potential confounders. Experiencing solitary confinement was significantly associated with PTSD symptoms among individuals accessing primary care following release from prison. Larger studies should confirm these findings.

  12. Test

    DEFF Research Database (Denmark)

    Bendixen, Carsten

    2014-01-01

    Bidrag med en kortfattet, introducerende, perspektiverende og begrebsafklarende fremstilling af begrebet test i det pædagogiske univers.......Bidrag med en kortfattet, introducerende, perspektiverende og begrebsafklarende fremstilling af begrebet test i det pædagogiske univers....

  13. Deformation of confined poly(ethylene oxide) in multilayer films.

    Science.gov (United States)

    Lai, Chuan-Yar; Hiltner, Anne; Baer, Eric; Korley, LaShanda T J

    2012-04-01

    The effect of confinement on the deformation behavior of poly(ethylene oxide) (PEO) was studied using melt processed coextruded poly(ethylene-co-acrylic acid) (EAA) and PEO multilayer films with varying PEO layer thicknesses from 3600 to 25 nm. The deformation mechanism was found to shift as layer thickness was decreased between 510 and 125 nm, from typical axial alignment of the crystalline fraction, as seen in bulk materials, to nonuniform micronecking mechanisms found in solution-grown single crystals. This change was evaluated via tensile testing, wide-angle X-ray diffraction (WAXD), atomic force microscopy (AFM), and differential scanning calorimetry (DSC). With the commercially relevant method of melt coextrusion, we were able to overcome the limitations to the testing of solution-grown single crystals, and the artifacts that occur from their handling, and bridged the gap in knowledge between thick bulk materials and thin single crystals.

  14. Measurements of uranium mass confined in high density plasmas

    Science.gov (United States)

    Stoeffler, R. C.

    1976-01-01

    An X-ray absorption method for measuring the amount of uranium confined in high density, rf-heated uranium plasmas is described. A comparison of measured absorption of 8 keV X-rays with absorption calculated using Beer Law indicated that the method could be used to measure uranium densities from 3 times 10 to the 16th power atoms/cu cm to 5 times 10 to the 18th power atoms/cu cm. Tests were conducted to measure the density of uranium in an rf-heated argon plasma with UF6 infection and with the power to maintain the discharge supplied by a 1.2 MW rf induction heater facility. The uranium density was measured as the flow rate through the test chamber was varied. A maximum uranium density of 3.85 times 10 to the 17th power atoms/cu cm was measured.

  15. The role of urine pregnancy testing in facilitating access to antenatal care and abortion services in South Africa: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Moodley Jennifer

    2006-08-01

    Full Text Available Abstract Background Effective confirmation of pregnancy is a basic component of reproductive health services. It is a prerequisite for accessing antenatal care (AnC if the pregnancy is wanted and abortion services if the pregnancy is unwanted. This study examined the role of urine pregnancy testing in the timing of presentation for pregnancy-care. Method A cross-sectional study was conducted among 158 women presenting for antenatal care and 164 women presenting for abortion at public sector clinics in Cape Town, South Africa. Results The median gestational age at first presentation was 23 weeks for AnC clients and 13 weeks for abortion clients. Obtaining a urine pregnancy test of one's own accord was associated with a decrease in the gestational age at presentation of 3.6 and 1.4 weeks for antenatal and abortion clients, respectively, independently of all other factors. Conclusion Given the proven clinical benefit and public health impact of early presentation for antenatal and abortion services, strategies to decrease gestational age at presentation for pregnancy care should be given priority. 'Fast-track' urine pregnancy testing services should be established in public sector clinics in South Africa.

  16. Factors influencing the uptake of Voluntary HIV Counseling and Testing among secondary school students in Arusha City, Tanzania: a cross sectional study.

    Science.gov (United States)

    Sanga, Zawadi; Kapanda, Gibson; Msuya, Sia; Mwangi, Rose

    2015-05-02

    Voluntary HIV counseling and testing (VCT) is a key strategy towards HIV prevention yet, the uptake of VCT services among young people remains low. This study determined the factors that influence the uptake of VCT among secondary school students in Arusha City, Tanzania. A cross sectional study using quantitative methods was conducted. A multi-stage sampling method was applied to randomly select the secondary schools. Stratification, random and systematic sampling techniques were used to identify the study participants. Interviews were conducted using structured questionnaires. Data analysis was done using statistical package for social sciences version 16. Analytical statistics were done using odds ratio to measure strength of association between VCT uptake and independent variables. Association with p-value towards VCT services. On VCT uptake, only 29.3% had ever tested. VCT uptake was found to be significantly predicted by age (p = 0.003), sex (p stigma and distance to the VCT centre. Integration of youth friendly VCT services in secondary schools would increase VCT uptake among secondary school students. Support and care received after knowing the test results should be clearly communicated as it helps motivate more young people towards VCT uptake and reduce stigma among them.

  17. Effect of home-based HIV counselling and testing on stigma and risky sexual behaviours: serial cross-sectional studies in Uganda.

    Science.gov (United States)

    Nuwaha, Fred; Kasasa, Simon; Wana, Godwill; Muganzi, Elly; Tumwesigye, Elioda

    2012-06-04

    A large, district-wide, home-based HIV counselling and testing (HBHCT) programme was implemented in Bushenyi district of Uganda from 2004 to 2007. This programme provided free HBHCT services to all consenting adults of Bushenyi district and had a very high uptake and acceptability. We measured population-level changes in knowledge of HIV status, stigma and HIV-risk behaviours before and after HBHCT to assess whether widespread HBHCT had an effect on trends of risky sexual behaviours and on stigma and discrimination towards HIV. Serial cross-sectional surveys were carried out before and after the implementation of HBHCT programme in Bushenyi district of Uganda. A total of 1402 randomly selected adults (18 to 49 years) were interviewed in the baseline survey. After the implementation, a different set of randomly selected 1562 adults was interviewed using the same questionnaire. Data was collected on socio-demographic characteristics, sexual behaviour, whether respondents had ever tested for HIV and stigma and discrimination towards HIV/AIDS. The proportion of people who had ever tested for HIV increased from 18.6% to 62% (pstigma and discrimination. Because HBCT programmes are cost-effective, they should be considered for implementation in delivery of HIV services especially in areas where access to HCT is low.

  18. Timed function tests, motor function measure, and quantitative thigh muscle MRI in ambulant children with Duchenne muscular dystrophy: A cross-sectional analysis.

    Science.gov (United States)

    Schmidt, Simone; Hafner, Patricia; Klein, Andrea; Rubino-Nacht, Daniela; Gocheva, Vanya; Schroeder, Jonas; Naduvilekoot Devasia, Arjith; Zuesli, Stephanie; Bernert, Guenther; Laugel, Vincent; Bloetzer, Clemens; Steinlin, Maja; Capone, Andrea; Gloor, Monika; Tobler, Patrick; Haas, Tanja; Bieri, Oliver; Zumbrunn, Thomas; Fischer, Dirk; Bonati, Ulrike

    2018-01-01

    The development of new therapeutic agents for the treatment of Duchenne muscular dystrophy has put a focus on defining outcome measures most sensitive to capture treatment effects. This cross-sectional analysis investigates the relation between validated clinical assessments such as the 6-minute walk test, motor function measure and quantitative muscle MRI of thigh muscles in ambulant Duchenne muscular dystrophy patients, aged 6.5 to 10.8 years (mean 8.2, SD 1.1). Quantitative muscle MRI included the mean fat fraction using a 2-point Dixon technique, and transverse relaxation time (T2) measurements. All clinical assessments were highly significantly inter-correlated with p quantitative muscle MRI values significantly correlated with all clinical assessments with the extensors showing the strongest correlation. In contrast to the clinical assessments, quantitative muscle MRI values were highly significantly correlated with age. In conclusion, the motor function measure and timed function tests measure disease severity in a highly comparable fashion and all tests correlated with quantitative muscle MRI values quantifying fatty muscle degeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Energy confinement scaling from the international stellarator database

    Energy Technology Data Exchange (ETDEWEB)

    Stroth, U. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Murakami, M.; Dory, R.A.; Yamada, H.; Okamura, S.; Sano, F.; Obiki, T.

    1995-09-01

    An international stellarator database on global energy confinement is presented comprising data from the ATF, CHS and Heliotron E heliotron/torsatrons and the W7-A and W7-AS shearless stellarators. Regression expressions for the energy confinement time are given for the individual devices and the combined dataset. A comparison with tokamak L mode confinement is discussed on the basis of various scaling expressions. In order to make this database available to interested colleagues, the structure of the database and the parameter list are explained in detail. More recent confinement results incorporating data from enhanced confinement regimes such as H mode are reported elsewhere. (author).

  20. Dimensional crossover in fluids under nanometer-scale confinement.

    Science.gov (United States)

    Das, Amit; Chakrabarti, J

    2012-05-01

    Several earlier studies have shown signatures of crossover in various static and dynamics properties of a confined fluid when the confining dimension decreases to about a nanometer. The density fluctuations govern the majority of such properties of a fluid. Here, we illustrate the crossover in density fluctuation in a confined fluid, to provide a generic understanding of confinement-induced crossover of fluid properties, using computer simulations. The crossover can be understood as a manifestation of changes in the long-wavelength behavior of fluctuation in density due to geometrical constraints. We further show that the confining potential significantly affects the crossover behavior.

  1. Confinement in a planar waveguide with porous silicon omnidirectional mirrors as confining walls

    International Nuclear Information System (INIS)

    Xifre-Perez, E.; Marsal, L.F.; Ferre-Borrull, J.; Pallares, J.

    2006-01-01

    We present the design and study of waveguide structures based on porous silicon where the light confinement is not due to the usual total reflection effect but to the use of photonic crystals (PCs) as confining walls. These PC are omnidirectional mirrors (OMs), consisting of the periodic repetition of two porous silicon layers with different refractive indices and thicknesses. They reflect the radiation for all angles of incidence within a frequency range called the omnidirectional band gap (OBG). We have followed the PC formalism to investigate the properties of the OM as a multimode waveguide: the number of modes within the band gap, their field spatial distribution and their confinement as a function of the frequency and the core thickness

  2. Confinement and propagation characteristics of subwavelength plasmonic modes

    International Nuclear Information System (INIS)

    Oulton, R F; Bartal, G; Zhang, X; Pile, D F P

    2008-01-01

    We have studied subwavelength confinement of the surface plasmon polariton modes of various plasmonic waveguides and examined their relative merits using a graphical parametric representation of their confinement and propagation characteristics. While the same plasmonic phenomenon governs mode confinement in all these waveguides, the various architectures can exhibit distinctive behavior in terms of effective mode area and propagation distance. We found that the waveguides based on metal and one dielectric material show a similar trade-off between energy confinement and propagation distance. However, a hybrid plasmon waveguide, incorporating metal, low index and high index dielectric materials, exhibits longer propagation distances for the same degree of confinement. We also point out that plasmonic waveguides with sharp features can provide an extremely strong local field enhancement, which is not necessarily accompanied by strong confinement of the total electromagnetic energy. In these waveguides, a mode may couple strongly to nearby atoms, but suffer relatively low propagation losses due to weak confinement.

  3. Theoretical studies of H2--H2 collisions. II. Scattering and transport cross sections of hydrogen at low energies: Tests of a new ab initio vibrotor potential

    International Nuclear Information System (INIS)

    Close-coupled calculations of scattering amplitudes have been carried out for H 2 --H 2 collisions for a new ab initio potential energy surface, treating the hydrogen molecules as true vibrotors. The amplitudes were inserted into the kinetic theory expressions for integral and transport cross sections and used to compute (1) the elastic scattering of (j=0, v=0) para-hydrogen for relative velocities between 1000 and 2500 m/sec; (2) the viscosity differences of ortho- and para-hydrogen for temperatures less than 25 0 K; and (3) the thermal diffusion ratio of ortho- and para-hydrogen for temperatures between 50 and 150 0 K. The agreement with experiment is highly satisfactory and provides a thoroughgoing test of the new potential energy surface

  4. Generation and Testing of the ENDF/B-VI Continuous-Energy Cross-Section Library for Use with Continuous-Energy Versions of KENO

    International Nuclear Information System (INIS)

    Goluoglu, Sedat; Dunn, Michael E.; Greene, Norman Maurice; Petrie Jr, Lester M.; Hollenbach, Daniel F.

    2007-01-01

    KENO V.a and KENO-VI are Monte Carlo codes that solve the multigroup form of the Boltzmann transport equation. These codes are part of the SCALE system of codes and are used for performing criticality calculations of systems with fissionable material. In general, continuous-energy Monte Carlo methods are preferred because such an approach avoids many of the assumptions inherent in the multigroup treatment. On the other hand, continuous-energy treatment is much more demanding in terms of computer storage space for data, memory requirements, and calculation speed. Continuous-energy versions of KENO V.a and KENO-VI have been created and are being extensively tested. Generation of ENDF/B-VI continuous-energy cross sections is explained, and the results of the validation and verification of the codes and the data are presented

  5. HIV care-seeking behaviour after HIV self-testing among men who have sex with men in Beijing, China: a cross-sectional study.

    Science.gov (United States)

    Ren, Xian-Long; Wu, Zun-You; Mi, Guo-Dong; McGoogan, Jennifer M; Rou, Ke-Ming; Zhao, Yan; Zhang, Nanci

    2017-06-28

    Men who have sex with men (MSM) has become the group with the fastest growing HIV epidemic in China. Since many Chinese MSM are conducting HIV self-testing, we aimed to determine the rate of HIV care seeking after self-testing, examine characteristics of "seekers" compared to "non-seekers," and explore factors associated with HIV care-seeking behaviour. A cross-sectional study design was used and an online survey was conducted in Beijing, China in 2016, among users of a popular Chinese gay networking smart phone application. Chi-square test was used to compare characteristics of those who sought HIV care ("seekers") and those who did not ("non-seekers"). Univariate and multivariate logistic regression analyses were conducted to assess factors associated with HIV care seeking. Among 21,785 screened, 2383 participants (10.9%) were included in the study. A total of 380 participants (15.9%) reported seeking HIV care after HIV self-testing while 2003 (84.1%) did not. Lack of knowledge of the "window period" (adjusted odds ratio [AOR] = 0.68, 95% confidence interval [95% CI] = 0.47-0.97, P = 0.04) was associated with reduced odds of seeking HIV care, while lower monthly income (AOR = 1.29, 95% CI = 1.03-1.62, P = 0.03) and obtaining HIV self-testing kits from health facilities (AOR = 2.40, 95% CI = 1.81-3.17, P seeking HIV care. Among those who sought HIV care, a large majority (92.4%) had non-reactive HIV self-testing results. Only 29 out of 265 with reactive, uncertain, or unknown results sought HIV care. We found a very low rate of HIV care seeking among our sample of urban Chinese MSM. The observation that most with reactive, uncertain, or unknown results did not seek HIV care is a cause for concern. These people should be paid more attention and helped to enter the care cascade. Our findings highlight that interventions aimed at improving linkage to care after HIV self-testing are urgently needed. However, further study is required to inform the

  6. Electron confinement in drift detectors by means of ``channel-stop`` implants: Characterization at high signal charges

    Energy Technology Data Exchange (ETDEWEB)

    Castoldi, A. [Univ. degli Studi di Milano (Italy). Dipt. di Fisica; Rehak, P. [Brookhaven National Lab., Upton, NY (United States); Strueder, L. [MPI Halbleiterlabor, Muenchen (Germany)

    1996-12-01

    Electron confinement in the direction transverse to the drift can be implemented in silicon drift detectors by means of deep p-implants. The reduced broadening of the electron cloud due to the deep p-implants has been tested as a function of the signal amplitude up to 200,000 electrons. The maximum number of electrons for which full confinement is achieved has been measured. The dependence of this threshold charge on the potential barrier generated by the deep p-implants, the size of the confinement, and the detector operating conditions are reported.

  7. Spherical microwave confinement and ball lightning

    Science.gov (United States)

    Robinson, William Richard

    This dissertation presents the results of research done on unconventional energy technologies from 1995 to 2009. The present civilization depends on an infrastructure that was constructed and is maintained almost entirely using concentrated fuels and ores, both of which will run out. Diffuse renewable energy sources rely on this same infrastructure, and hence face the same limitations. I first examined sonoluminescence directed toward fusion, but demonstrated theoretically that this is impossible. I next studied Low Energy Nuclear Reactions and developed methods for improving results, although these have not been implemented. In 2000, I began Spherical Microwave Confinement (SMC), which confines and heats plasma with microwaves in a spherical chamber. The reactor was designed and built to provide the data needed to investigate the possibility of achieving fusion conditions with microwave confinement. A second objective was to attempt to create ball lightning (BL). The reactor featured 20 magnetrons, which were driven by a capacitor bank and operated in a 0.2 s pulse mode at 2.45 GHz. These provided 20 kW to an icosahedral array of 20 antennas. Video of plasmas led to a redesign of the antennas to provide better coupling of the microwaves to the plasma. A second improvement was a grid at the base of the antennas, which provided corona electrons and an electric field to aid quick formation of plasmas. Although fusion conditions were never achieved and ball lightning not observed, experience gained from operating this basic, affordable system has been incorporated in a more sophisticated reactor design intended for future research. This would use magnets that were originally planned. The cusp geometry of the magnetic fields is suitable for electron cyclotron resonance in the same type of closed surface that in existing reactors has generated high-temperature plasmas. Should ball lightning be created, it could be a practical power source with nearly ideal

  8. Properties of confined states in phase dynamics

    International Nuclear Information System (INIS)

    Brand, H.R.; Deissler, R.J.

    1990-01-01

    In this paper we point out that for the confined states discussed recently for the phase associated with a stationary pattern, a conservation law for both the phase variation and the local wave vector exists. We discuss the physical implications of this observation as a function of the imposed boundary conditions. We investigate the influence of noise and we find that for the phase change and for the local wave vector, the stationary solution of the associated functional differential Fokker-Planck equation can be explicitly given

  9. Confining quark condensate model of the nucleon.

    Energy Technology Data Exchange (ETDEWEB)

    Frank, Michael; Tandy, Peter

    1992-07-01

    We obtain a mean-field solution for the nucleon as a quark-meson soliton obtained from the action of the global color-symmetry model of QCD. All dynamics is generated from an effective interaction of quark currents. At the quark-meson level there are two novel features: (1) absolute confinement is produced from the space-time structure of the dynamical self-energy in the vacuum quark propagator; and (2) the related scalar meson field is an extended q-barq composite that couples nonlocally to quarks. The influence of these features upon the nucleon mass contributions and other nucleon properties is presented.

  10. The Gribov theory of quark confinement

    CERN Document Server

    2001-01-01

    V N Gribov, one of the founders of modern particle physics, shaped our understanding of QCD as the microscopic dynamics of hadrons. This volume collects his papers on quark confinement, showing the road he followed to arrive at the theory and formulating the theory itself. It begins with papers providing a beautiful physical explanation of asymptotic freedom based on the phenomenon of antiscreening and demonstrating the inconsistency of the standard perturbative treatment of the gluon fields (Gribov copies, Gribov horizon). It continues with papers presenting the Gribov theory according to whi

  11. Central cell confinement in MFTF-B

    International Nuclear Information System (INIS)

    Jong, R.A.

    1981-01-01

    The point code TANDEM has been used to survey the range of plasma parameters which can be attained in MFTF-B. The code solves for the electron and ion densities and temperatures in the central cell, yin-yang, barrier, and A-cell regions as well as the plasma potential in each region. In these studies, the A-cell sloshing ion beams were fixed while the neutral beams in the yin-yang and central cell, the gas feed in the central cell, and the applied ECRH power β, central cell ion density and temperature, and the confining potential are discussed

  12. Microwave Reflectometry for Magnetically Confined Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Mazzucato, E.

    1998-02-01

    This paper is about microwave reflectometry -- a radar technique for plasma density measurements using the reflection of electromagnetic waves by a plasma cutoff. Both the theoretical foundations of reflectometry and its practical application to the study of magnetically confined plasmas are reviewed in this paper. In particular, the role of short-scale density fluctuations is discussed at length, both as a unique diagnostic tool for turbulence studies in thermonuclear plasmas and for the deleterious effects that fluctuations may have on the measurement of the average plasma density with microwave reflectometry.

  13. Quasigluon lifetime and confinement from first principles

    Science.gov (United States)

    Siringo, Fabio

    2017-12-01

    The mass and the lifetime of a gluon are evaluated from first principles at a finite temperature across the deconfinement transition of pure SU(3) Yang-Mills theory, by a direct calculation of the pole of the propagator in the complex plane, using the finite temperature extension of a massive expansion in the Landau gauge. Even at T =0 , the quasigluon lifetime is finite, and the gluon is canceled from the asymptotic states, yielding a microscopic proof of confinement from first principles. Above the transition, the damping rate is a linear increasing function of temperature as predicted by standard perturbation theory.

  14. Micromachining of inertial confinement fusion targets

    International Nuclear Information System (INIS)

    Gobby, P.L.; Salzer, L.J.; Day, R.D.

    1996-01-01

    Many experiments conducted on today's largest inertial confinement fusion drive lasers require target components with sub-millimeter dimensions, precisions of a micron or less and surface finishes measured in nanometers. For metal and plastic, techniques using direct machining with diamond tools have been developed that yield the desired parts. New techniques that will be discussed include the quick-flip locator, a magnetically held kinematic mount that has allowed the direct machining of millimeter-sized beryllium hemishells whose inside and outside surface are concentric to within 0.25 micron, and an electronic version of a tracer lathe which has produced precise azimuthal variations of less than a micron

  15. k-connectivity for confined random networks

    Science.gov (United States)

    Georgiou, Orestis; Dettmann, Carl P.; Coon, Justin P.

    2013-07-01

    k-connectivity is an important measure of network robustness and resilience to random faults and disruptions. We undertake both local and global approaches to k-connectivity and calculate closed-form analytic formulas for the probability that a confined random network remains fully connected after the removal of k - 1 nodes. Our analysis reveals that k-connectivity is governed by microscopic details of the network domain such as sharp corners rather than the macroscopic total volume. Hence, our results can aid in the design of reliable networks, an important problem in, e.g., wireless ad hoc and sensor networks.

  16. Effects of Confinement on Conventional Spin Problems

    DEFF Research Database (Denmark)

    Marchukov, Oleksandr

    2015-01-01

    , Hubbard model, etc., which are nevertheless used to describe physical phenomena in various fields, such as condensed matter physics, nuclear physics, etc. This dissertation discusses the effects of the external confinement on some con- ventional spin problems. It consists of two parts: In the first part...... the effects of spin-orbit coupling on particles trapped in a two-dimensional harmonic oscilla- tor are considered. The influences of the deformation of the trap, interparticle interaction and external magnetic field are analyzed. The statistical analysis of the single-particle energy spectrum and its relation...

  17. Isolation and confinement - Considerations for colonization

    Science.gov (United States)

    Akins, F. R.

    1978-01-01

    This paper discusses three types of isolation (sensory/perceptual, temporal, and social) that could adversely affect mankind in space. The literature dealing with laboratory and field experiments relevant to these areas is summarized and suggestions are given for dealing with these problems within the space colony community. Also, consideration is given to the potential effects of physical confinement and the need for usable space. Finally, a modification of Maslow's hierarchy of needs is proposed as a theoretical framework to understand and investigate mankind's psychological needs in space.

  18. Reversible Clustering of Gold Nanoparticles under Confinement.

    Science.gov (United States)

    Sánchez-Iglesias, Ana; Claes, Nathalie; Solís, Diego M; Taboada, Jose M; Bals, Sara; Liz-Marzán, Luis M; Grzelczak, Marek

    2018-03-12

    A limiting factor of solvent-induced nanoparticle self-assembly is the need for constant sample dilution in assembly/disassembly cycles. Changes in the nanoparticle concentration alter the kinetics of the subsequent assembly process, limiting optical signal recovery. Herein, we show that upon confining hydrophobic nanoparticles in permeable silica nanocapsules, the number of nanoparticles participating in cyclic aggregation remains constant despite bulk changes in solution, leading to highly reproducible plasmon band shifts at different solvent compositions. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Correlation of Nondestructive Pavement Evaluation Test Results with Results of Conventional Quality Control and In-Situ Strength Tests on an MX Road Test Section. Volume 2. Appendix A.

    Science.gov (United States)

    1986-02-01

    through 5 are pressented in Figure A36. These ruts are actually changes in surface elevation as determined from cross -section and profile data (rod...placed on a nest of circular plates (base diameter = 30 in.) and the resulting deflection is measured. The modulus of soil reaction, k , is defined as...pavement structure. DSM is defined as the inverse slope of the load-deflection curve and has units of kips/inch. Frequency can be varied from

  20. Confinement of ultra-cold neutron in a multiple cusp magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Nobumichi; Inoue, Nobuyuki; Nihei, Hitoshi; Kinosita, Ken-ichi [Tokyo Univ. (Japan). Faculty of Engineering

    1996-08-01

    A new confinement system of ultra-cold neutrons is proposed. The neutron bottle is made of a rectangular vacuum chamber with the size of 40 cm x 40 cm x 30 cm covered with arrays of bar type permanent magnets. The operation of bottle requires neither cooling system nor high electric power supply, and thereby the bottle is appropriate to use in the room which is located in controlled area. The maximum kinetic energy of neutrons confined is 20 neV. Experimental scheme to test the performance of the bottle is described. (author)

  1. Using Balance Tests to Discriminate Between Participants With a Recent Index Lateral Ankle Sprain and Healthy Control Participants: A Cross-Sectional Study.

    Science.gov (United States)

    Pourkazemi, Fereshteh; Hiller, Claire; Raymond, Jacqueline; Black, Deborah; Nightingale, Elizabeth; Refshauge, Kathryn

    2016-03-01

    The first step to identifying factors that increase the risk of recurrent ankle sprains is to identify impairments after a first sprain and compare performance with individuals who have never sustained a sprain. Few researchers have restricted recruitment to a homogeneous group of patients with first sprains, thereby introducing the potential for confounding. To identify impairments that differ in participants with a recent index lateral ankle sprain versus participants with no history of ankle sprain. Cross-sectional study. We recruited a sample of convenience from May 2010 to April 2013 that included 70 volunteers (age = 27.4 ± 8.3 years, height = 168.7 ± 9.5 cm, mass = 65.0 ± 12.5 kg) serving as controls and 30 volunteers (age = 31.1 ± 13.3 years, height = 168.3 ± 9.1 cm, mass = 67.3 ± 13.7 kg) with index ankle sprains. We collected demographic and physical performance variables, including ankle-joint range of motion, balance (time to balance after perturbation, Star Excursion Balance Test, foot lifts during single-legged stance, demi-pointe balance test), proprioception, motor planning, inversion-eversion peak power, and timed stair tests. Discriminant analysis was conducted to determine the relationship between explanatory variables and sprain status. Sequential discriminant analysis was performed to identify the most relevant variables that explained the greatest variance. The average time since the sprain was 3.5 ± 1.5 months. The model, including all variables, correctly predicted a sprain status of 77% (n = 23) of the sprain group and 80% (n = 56) of the control group and explained 40% of the variance between groups ([Formula: see text] = 42.16, P = .03). Backward stepwise discriminant analysis revealed associations between sprain status and only 2 tests: Star Excursion Balance Test in the anterior direction and foot lifts during single-legged stance ([Formula: see text] = 15.2, P = .001). These 2 tests explained 15% of the between-groups variance

  2. Summary and evaluation of hydraulic property data available for the Hanford Site upper basalt confined aquifer system

    International Nuclear Information System (INIS)

    Spane, F.A. Jr.; Vermeul, V.R.

    1994-09-01

    Pacific Northwest Laboratory, as part of the Hanford Site Ground-Water Surveillance Project, examines the potential for offsite migration of contamination within the upper basalt confined aquifer system. For the past 40 years, hydrologic testing of the upper basalt confined aquifer has been conducted by a number of Hanford Site programs. Hydraulic property estimates are important for evaluating aquifer flow characteristics (i.e., ground-water flow patterns, flow velocity, transport travel time). Presented are the first comprehensive Hanford Site-wide summary of hydraulic properties for the upper basalt confined aquifer system (i.e., the upper Saddle Mountains Basalt). Available hydrologic test data were reevaluated using recently developed diagnostic test analysis methods. A comparison of calculated transmissivity estimates indicates that, for most test results, a general correspondence within a factor of two between reanalysis and previously reported test values was obtained. For a majority of the tests, previously reported values are greater than reanalysis estimates. This overestimation is attributed to a number of factors, including, in many cases, a misapplication of nonleaky confined aquifer analysis methods in previous analysis reports to tests that exhibit leaky confined aquifer response behavior. Results of the test analyses indicate a similar range for transmissivity values for the various hydro-geologic units making up the upper basalt confined aquifer. Approximately 90% of the calculated transmissivity values for upper basalt confined aquifer hydrogeologic units occur within the range of 10 0 to 10 2 m 2 /d, with 65% of the calculated estimate values occurring between 10 1 to 10 2 m 2 d. These summary findings are consistent with the general range of values previously reported for basalt interflow contact zones and sedimentary interbeds within the Saddle Mountains Basalt

  3. Summary and evaluation of hydraulic property data available for the Hanford Site upper basalt confined aquifer system

    Energy Technology Data Exchange (ETDEWEB)

    Spane, F.A. Jr.; Vermeul, V.R.

    1994-09-01

    Pacific Northwest Laboratory, as part of the Hanford Site Ground-Water Surveillance Project, examines the potential for offsite migration of contamination within the upper basalt confined aquifer system. For the past 40 years, hydrologic testing of the upper basalt confined aquifer has been conducted by a number of Hanford Site programs. Hydraulic property estimates are important for evaluating aquifer flow characteristics (i.e., ground-water flow patterns, flow velocity, transport travel time). Presented are the first comprehensive Hanford Site-wide summary of hydraulic properties for the upper basalt confined aquifer system (i.e., the upper Saddle Mountains Basalt). Available hydrologic test data were reevaluated using recently developed diagnostic test analysis methods. A comparison of calculated transmissivity estimates indicates that, for most test results, a general correspondence within a factor of two between reanalysis and previously reported test values was obtained. For a majority of the tests, previously reported values are greater than reanalysis estimates. This overestimation is attributed to a number of factors, including, in many cases, a misapplication of nonleaky confined aquifer analysis methods in previous analysis reports to tests that exhibit leaky confined aquifer response behavior. Results of the test analyses indicate a similar range for transmissivity values for the various hydro-geologic units making up the upper basalt confined aquifer. Approximately 90% of the calculated transmissivity values for upper basalt confined aquifer hydrogeologic units occur within the range of 10{sup 0} to 10{sup 2} m{sup 2}/d, with 65% of the calculated estimate values occurring between 10{sup 1} to 10{sup 2} m{sup 2}d. These summary findings are consistent with the general range of values previously reported for basalt interflow contact zones and sedimentary interbeds within the Saddle Mountains Basalt.

  4. Decreased re-conviction rates of DUI offenders with intensive supervision and home confinement.

    Science.gov (United States)

    Barta, William D; Fisher, Virginia; Hynes, Patrick

    2017-11-01

    In some jurisdictions, persons who are convicted of driving under the influence of alcohol (DUI) are allowed to serve some portion of their prison sentence under home confinement as part of Intensive Supervision Programs (ISPs) which include pre-release psycho-education and close post-release supervision. Test the hypothesis that persons convicted of DUI offenses who have spent some portion of their sentence under home confinement, as compared to a historical comparison group, will exhibit a relatively low re-conviction rate. Using administrative data for 1,410 repeat DUI offenders (302 members of the historical comparison group, 948 ISP members, and 160 persons who appear in both groups at different points in time), with a follow-up period of up to 3 years and 10 months, a marginal Cox model was employed to compare conviction rates of persons who experienced intensive supervision and home confinement with historical comparison group members. Persons with ISP + home confinement experience a re-conviction rate that is less than half that observed in the comparison group. Age, ethnicity (white vs. non-white), and gender are also significant predictors of re-conviction. Home confinement, in conjunction with psycho-education and other program elements, is one means of reducing the costs of incarceration. The results of this study suggest that, in addition to cost savings, states may realize a public safety benefit in the form of a reduction in DUI offense rates.

  5. Performance Analysis of CFRP Composite Strips Confined RC Columns under Axial Compression

    Directory of Open Access Journals (Sweden)

    J. Raja Murugadoss

    2015-01-01

    Full Text Available In an attempt to mitigate the high cost of FRP composite strengthening, an experimental investigation was carried out that sought to achieve efficient and most favorable FRP strengthening using CFRP composite strips. 50 mm wide CFRP composite strips were used in two different spacings (20 mm and 40 mm to confine columns. The test results of the column confined with smaller spacing (20 mm showed significant restraint of axial deformation of the column and enhanced the strength capacity to a maximum of 99.20% compared to that of reference column. In contrast, the column confined by strips with larger spacing (40 mm failed by crushing of concrete alone, which occurred even before the CFRP strips reached their ultimate strain. In addition, the embodied energy that exists in the CFRP strips could not be utilized effectively. The stress and strength enhancement ratio of this present study was compared with the previous research that has been conducted on columns confined with full wrapping. From the obtained results, it is recommended that CFRP strips with a spacing of 20 mm be used to improve the strength capacity of the RC column; in addition, this wrapping technique provides economic benefits compared to a column confined with full wrapping.

  6. Experimental Investigation of Concrete Filled PVC Tube Columns Confined By Plain PVC Socket

    Directory of Open Access Journals (Sweden)

    Jamaluddin N.

    2017-01-01

    Full Text Available This paper presents results of an experimental study for concrete column filled poly vinyl chloride (PVC tubes confined by plain socket with 5.8 & 6.8 mm thicknesses, 102 mm diameter and 100 mm depth. The total of five concrete filled columns using PVC tubes (CFT PVC was tested to investigate the columns’ behaviour. The column is 700 mm height, 100 mm external diameter and 3.5 mm tube thickness with different thickness of plain socket. The results presented include maximum axial load, plain socket confinement effect, the mode of failure, and lateral PVC strain. The axial load enhancement of PVC-concrete columns confined using plain socket shows an increment of 21.3% up to 55.2% and axial strain from 21% to 40% compared with displacement for control composite columns at 192 kN ultimate load.

  7. Pellet injection with improved confinement in ASDEX

    International Nuclear Information System (INIS)

    Kaufmann, M.; Buechl, K.; Fussmann, G.; Gehre, O.; Grassie, K.; Gruber, O.; Haas, G.; Janeschitz, G.; Kornherr, M.; Lackner, K.; Lang, R.S.; Mast, K.F.; McCormick, K.; Mertens, V.; Neuhauser, J.; Niedermeyer, H.; Sandmann, W.; Zasche, D.; Zehrfeld, H.P.; Pietrzyk, Z.A.

    1987-07-01

    Tokamak discharges with repetitive pellet fueling were investigated in the ASDEX divertor device. The importance of sufficiently high divertor recycling for successful density build-up in the bulk plasma was demonstrated. In OH-heated discharges with high recycling an energy confinement time of 160 ms was reached, the normal values being 80 ms in the roll-over region. The peaked density profiles in this cases were accompanied by reduced or suppressed sawtooth activity and finally ended in a phase of strong central impurity accumulation. The particle transport was characterized by strong, non-classical inward drift, while the improved energy transport can be explained by two alternatives: (1) a local model which assumes neo-Alcator χ e for the electrons and an χ i = 3χ neocl for the ions in the gas puff cases reduced to χ i = χ neocl for the optimum pellet cases; (2) a profile consistency picture were T e (a) determines the energy confinement. Low-power, NI-heated discharges with pellet fueling behave like ohmic discharges, while for high power in the L-mode no successful density build-up was possible, and τ E was not improved. The H-regime was extended to anti n e = 1.2x10 20 m -3 by the injection of pellets. In this case a density build-up takes place, but a further density profile peaking could not be observed. (orig.)

  8. Thermodynamic properties of bulk and confined water

    Energy Technology Data Exchange (ETDEWEB)

    Mallamace, Francesco, E-mail: francesco.mallamace@unime.it [Dipartimento di Fisica e Scienza della Terra Università di Messina and CNISM, I-98168 Messina (Italy); Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215 (United States); Corsaro, Carmelo [Dipartimento di Fisica e Scienza della Terra Università di Messina and CNISM, I-98168 Messina (Italy); Mallamace, Domenico [Dipartimento di Scienze dell' Ambiente, della Sicurezza, del Territorio, degli Alimenti e della Salute, Università di Messina, I-98166 Messina (Italy); Vasi, Sebastiano; Vasi, Cirino [IPCF-CNR, I-98166 Messina (Italy); Stanley, H. Eugene [Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215 (United States)

    2014-11-14

    The thermodynamic response functions of water display anomalous behaviors. We study these anomalous behaviors in bulk and confined water. We use nuclear magnetic resonance (NMR) to examine the configurational specific heat and the transport parameters in both the thermal stable and the metastable supercooled phases. The data we obtain suggest that there is a behavior common to both phases: that the dynamics of water exhibit two singular temperatures belonging to the supercooled and the stable phase, respectively. One is the dynamic fragile-to-strong crossover temperature (T{sub L} ≃ 225 K). The second, T{sup *} ∼ 315 ± 5 K, is a special locus of the isothermal compressibility K{sub T}(T, P) and the thermal expansion coefficient α{sub P}(T, P) in the P–T plane. In the case of water confined inside a protein, we observe that these two temperatures mark, respectively, the onset of protein flexibility from its low temperature glass state (T{sub L}) and the onset of the unfolding process (T{sup *})

  9. Velocity Dependence of Friction of Confined Hydrocarbons

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, Vladimir N.; Persson, Bo N. J.

    2010-01-01

    We present molecular dynamics friction calculations for confined hydrocarbon “polymer” solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: (a) polymer sliding against a hard substrate and (b) polymer sliding on polymer. We discuss the velocity dependence of the f......We present molecular dynamics friction calculations for confined hydrocarbon “polymer” solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: (a) polymer sliding against a hard substrate and (b) polymer sliding on polymer. We discuss the velocity dependence...... of the frictional shear stress for both cases. In our simulations, the polymer films are very thin (∼3 nm), and the solid walls are connected to a thermostat at a short distance from the polymer slab. Under these circumstances we find that frictional heating effects are not important, and the effective temperature...... in the polymer film is always close to the thermostat temperature. In the first setup (a), for hydrocarbons with molecular lengths from 60 to 1400 carbon atoms, the shear stresses are nearly independent of molecular length, but for the shortest hydrocarbon C20H42 the frictional shear stress is lower. In all...

  10. Congestion and communication in confined ant traffic

    Science.gov (United States)

    Gravish, Nick; Gold, Gregory; Zangwill, Andrew; Goodisman, Michael A. D.; Goldman, Daniel I.

    2014-03-01

    Many social animals move and communicate within confined spaces. In subterranean fire ants Solenopsis invicta, mobility within crowded nest tunnels is important for resource and information transport. Within confined tunnels, communication and traffic flow are at odds: trafficking ants communicate through tactile interactions while stopped, yet ants that stop to communicate impose physical obstacles on the traffic. We monitor the bi-directional flow of fire ant workers in laboratory tunnels of varied diameter D. The persistence time of communicating ant aggregations, τ, increases approximately linearly with the number of participating ants, n. The sensitivity of traffic flow increases as D decreases and diverges at a minimum diameter, Dc. A cellular automata model incorporating minimal traffic features--excluded volume and communication duration--reproduces features of the experiment. From the model we identify a competition between information transfer and the need to maintain jam-free traffic flow. We show that by balancing information transfer and traffic flow demands, an optimum group strategy exists which maximizes information throughput. We acknowledge funding from NSF PoLS #0957659 and #PHY-1205878.

  11. Dual Higgs theory for color confinement

    International Nuclear Information System (INIS)

    Ichie, H.; Suganuma, H.

    1999-01-01

    We study theoretical bases of the dual Higgs theory for confinement physics in QCD in terms of monopoles and the gluon configuration in the maximally abelian (MA) gauge. Abelian dominance for the confinement force can be analytically proved by regarding the off-diagonal angle variable as a random variable in the lattice formalism. In the long-distance scale, the contribution of off-diagonal gluons to the Wilson loop cancels each other and exhibits a perimeter law behavior, which leads to exact abelian dominance on the string tension if the finite size effect of the Wilson loop is removed. We investigate the appearance of the monopole in the QCD vacuum, considering the role of off-diagonal gluons. The monopole carries a large fluctuation of the gluon field and provides a large abelian action in abelian projected QCD. Due to the partial cancellation between the abelian part and the off-diagonal part of the QCD action, the monopole can appear in QCD without large cost of the QCD action. The off-diagonal gluon is necessary for existence of the monopole at the short-distance scale. We study monopole condensation, which is the requirement of the dual Higgs theory, by comparing the QCD vacuum with the monopole-current system. We find that 'entropy' of monopole-current dominates than its 'energy', and the monopole seems to be condensed at the infrared scale in the QCD vacuum. Copyright (1999) World Scientific Publishing Co. Pte. Ltd

  12. Quantum chromodynamics near the confinement limit

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, C.

    1985-09-01

    These nine lectures deal at an elementary level with the strong interaction between quarks and its implications for the structure of hadrons. Quarkonium systems are studied as a means for measuring the interquark interaction. This is presumably (part of) the answer a solution to QCD must yield, if it is indeed the correct theory of the strong interactions. Some elements of QCD are reviewed, and metaphors for QCD as a confining theory are introduced. The 1/N expansion is summarized as a way of guessing the consequences of QCD for hadron physics. Lattice gauge theory is developed as a means for going beyond perturbation theory in the solution of QCD. The correspondence between statistical mechanics, quantum mechanics, and field theory is made, and simple spin systems are formulated on the lattice. The lattice analog of local gauge invariance is developed, and analytic methods for solving lattice gauge theory are considered. The strong-coupling expansion indicates the existence of a confining phase, and the renormalization group provides a means for recovering the consequences of continuum field theory. Finally, Monte Carlo simulations of lattice theories give evidence for the phase structure of gauge theories, yield an estimate for the string tension characterizing the interquark force, and provide an approximate description of the quarkonium potential in encouraging good agreement with what is known from experiment.

  13. Self-consistent model of confinement

    International Nuclear Information System (INIS)

    Swift, A.R.

    1988-01-01

    A model of the large-spatial-distance, zero--three-momentum, limit of QCD is developed from the hypothesis that there is an infrared singularity. Single quarks and gluons do not propagate because they have infinite energy after renormalization. The Hamiltonian formulation of the path integral is used to quantize QCD with physical, nonpropagating fields. Perturbation theory in the infrared limit is simplified by the absence of self-energy insertions and by the suppression of large classes of diagrams due to vanishing propagators. Remaining terms in the perturbation series are resummed to produce a set of nonlinear, renormalizable integral equations which fix both the confining interaction and the physical propagators. Solutions demonstrate the self-consistency of the concepts of an infrared singularity and nonpropagating fields. The Wilson loop is calculated to provide a general proof of confinement. Bethe-Salpeter equations for quark-antiquark pairs and for two gluons have finite-energy solutions in the color-singlet channel. The choice of gauge is addressed in detail. Large classes of corrections to the model are discussed and shown to support self-consistency

  14. Polymer escape from a confining potential

    International Nuclear Information System (INIS)

    Mökkönen, Harri; Ikonen, Timo; Jónsson, Hannes; Ala-Nissila, Tapio

    2014-01-01

    The rate of escape of polymers from a two-dimensionally confining potential well has been evaluated using self-avoiding as well as ideal chain representations of varying length, up to 80 beads. Long timescale Langevin trajectories were calculated using the path integral hyperdynamics method to evaluate the escape rate. A minimum is found in the rate for self-avoiding polymers of intermediate length while the escape rate decreases monotonically with polymer length for ideal polymers. The increase in the rate for long, self-avoiding polymers is ascribed to crowding in the potential well which reduces the free energy escape barrier. An effective potential curve obtained using the centroid as an independent variable was evaluated by thermodynamic averaging and Kramers rate theory then applied to estimate the escape rate. While the qualitative features are well reproduced by this approach, it significantly overestimates the rate, especially for the longer polymers. The reason for this is illustrated by constructing a two-dimensional effective energy surface using the radius of gyration as well as the centroid as controlled variables. This shows that the description of a transition state dividing surface using only the centroid fails to confine the system to the region corresponding to the free energy barrier and this problem becomes more pronounced the longer the polymer is. A proper definition of a transition state for polymer escape needs to take into account the shape as well as the location of the polymer

  15. Using Quantum Confinement to Uniquely Identify Devices

    Science.gov (United States)

    Roberts, J.; Bagci, I. E.; Zawawi, M. A. M.; Sexton, J.; Hulbert, N.; Noori, Y. J.; Young, M. P.; Woodhead, C. S.; Missous, M.; Migliorato, M. A.; Roedig, U.; Young, R. J.

    2015-11-01

    Modern technology unintentionally provides resources that enable the trust of everyday interactions to be undermined. Some authentication schemes address this issue using devices that give a unique output in response to a challenge. These signatures are generated by hard-to-predict physical responses derived from structural characteristics, which lend themselves to two different architectures, known as unique objects (UNOs) and physically unclonable functions (PUFs). The classical design of UNOs and PUFs limits their size and, in some cases, their security. Here we show that quantum confinement lends itself to the provision of unique identities at the nanoscale, by using fluctuations in tunnelling measurements through quantum wells in resonant tunnelling diodes (RTDs). This provides an uncomplicated measurement of identity without conventional resource limitations whilst providing robust security. The confined energy levels are highly sensitive to the specific nanostructure within each RTD, resulting in a distinct tunnelling spectrum for every device, as they contain a unique and unpredictable structure that is presently impossible to clone. This new class of authentication device operates with minimal resources in simple electronic structures above room temperature.

  16. Confinement of helium tides by aerogel

    Science.gov (United States)

    Dolesi, R.; Bonaldi, M.; Vitale, S.

    1999-12-01

    In the context of scientific space missions that use liquid helium as a coolant, many methods have been proposed to solve the problem of helium confinement. This problem is particularly relevant for those missions which carry on board sensitive accelerometers, because the sub-millimetre motion of the liquid-vapour interface due to the varying gravitational field amplifies the gravitational disturbances beyond the affordable level. Within this framework it has been proposed to use the strong Van der Waals and capillary forces that rise in nanometer sized pores of aerogel to confine helium. Aerogel is a space qualified material and many of its properties have been already studied to a large extent. Its pores occupy a volume always larger than at least 90% of the total volume, with an overall density comparable to the density of the helium liquid itself. We report here on a preliminary experiment that has investigated, by means of the torsion pendulum method, the He II behaviour when only partially filling an aerogel sample. For pressure values below saturation, we observed in particular a high "tortuosity" of the liquid-vapour interface. This supports the idea that even a gravitational field of 1 g does not overcome capillary forces in shaping the superfluid configuration in aerogel.

  17. Block copolymer morphologies confined by square-shaped particle: Hard and soft confinement

    International Nuclear Information System (INIS)

    Zhang Qiyi; Yang Wenyan; Hu Kaiyan

    2016-01-01

    The self-assembly of diblock copolymers confined around one square-shaped particle is studied systematically within two-dimensional self-consistent field theory (SCFT). In this model, we assume that the thin block copolymer film is confined in the vicinity of a square-shaped particle by a homopolymer melt, which is equivalent to the poor solvents. Multiple sequences of square-shaped particle-induced copolymer aggregates with different shapes and self-assembled internal morphologies are predicted as functions of the particle size, the structural portion of the copolymer, and the volume fraction of the copolymer. A rich variety of aggregates are found with complex internal self-assembled morphologies including complex structures of the vesicle, with one or several inverted micelle surrounded by the outer monolayer with the particle confined in the core. These results demonstrate that the assemblies of diblock copolymers formed around the square-shaped particle in poor solvents are of immediate interest to the assembly of copolymer and the morphology of biomembrane in the confined environment, as well as to the transitions of vesicles to micelles. (paper)

  18. From Pauli's birthday to 'Confinement Resonances' - a potted history of Quantum Confinement

    Science.gov (United States)

    Connerade, J. P.

    2013-06-01

    Quantum Confinement is in some sense a new subject. International meetings dedicated to Quantum Confinement have occurred only recently in Mexico City (the first in 2010 and the second, in September 2011). However, at least in principle, the subject has existed since a very long time. Surprisingly perhaps, it lay dormant for many years, for want of suitable experimental examples. However, when one looks carefully at its origin, it turns out to have a long and distinguished history. In fact, the problem of quantum confinement raises a number of very interesting issues concerning boundary conditions in elementary quantum mechanics and how they should be applied to real problems. Some of these issues were missed in the earliest papers, but are implicit in the structure of quantum mechanics, and lead to the notion of Confinement Resonances, the existence of which was predicted theoretically more than ten years ago. Although, for several reasons, these resonances remained elusive for a very long time, they have now been observed experimentally, which puts the whole subject in much better shape and, together with the advent of metallofullerenes, has contributed to its revival.

  19. Population normative data for the 10/66 Dementia Research Group cognitive test battery from Latin America, India and China: a cross-sectional survey

    Directory of Open Access Journals (Sweden)

    Yang Fang

    2009-08-01

    Full Text Available Abstract Background 1 To report site-specific normative values by age, sex and educational level for four components of the 10/66 Dementia Research Group cognitive test battery; 2 to estimate the main and interactive effects of age, sex, and educational level by site; and 3 to investigate the effect of site by region and by rural or urban location. Methods Population-based cross-sectional one phase catchment area surveys were conducted in Cuba, Dominican Republic, Venezuela, Peru, Mexico, China and India. The protocol included the administration of the Community Screening Instrument for Dementia (CSI 'D', generating the COGSCORE measure of global function, and the Consortium to Establish a Registry for Alzheimer's Disease (CERAD verbal fluency (VF, word list memory (WLM, immediate recall and recall (WLR, delayed recall tests. Only those free of dementia were included in the analysis. Results Older people, and those with less education performed worse on all four tests. The effect of sex was much smaller and less consistent. There was a considerable effect of site after accounting for compositional differences in age, education and sex. Much of this was accounted for by the effect of region with Chinese participants performing better, and Indian participants worse, than those from Latin America. The effect of region was more prominent for VF and WLM than for COGSCORE and WLR. Conclusion Cognitive assessment is a basic element for dementia diagnosis. Age- and education-specific norms are required for this purpose, while the effect of gender can probably be ignored. The basis of cultural effects is poorly understood, but our findings serve to emphasise that normative data may not be safely generalised from one population to another with quite different characteristics. The minimal effects of region on COGSCORE and WLR are reassuring with respect to the cross-cultural validity of the 10/66 dementia diagnosis, which uses only these elements of the 10

  20. Marine Hydrokinetic (MHK) Energy Conversion Research at UNH: From Fundamental Studies of Hydrofoil Sections, to Moderate Reynolds Number Turbine Tests in a Tow Tank, to Open Water Deployments at Tidal Energy Test Sites (Invited)

    Science.gov (United States)

    Wosnik, M.; Bachant, P.; Nedyalkov, I.; Rowell, M.; Dufresne, N.; Lyon, V.

    2013-12-01

    We report on research related to MHK turbines at the Center for Ocean Renewable Energy (CORE) at the University of New Hampshire (UNH). The research projects span varies scales, levels of complexity and environments - from fundamental studies of hydrofoil sections in a high speed water tunnel, to moderate Reynolds number turbine tests with inflow and wake studies in a large cross-section tow tank, to deployments of highly instrumented process models at tidal energy test sites in New England. A concerted effort over the past few years has brought significant new research infrastructure for marine hydrokinetic energy conversion online at UNH-CORE. It includes: a high-speed cavitation tunnel with independent control of velocity and pressure; a highly accurate tow mechanism, turbine test bed and wake traversing system for the 3.7m x 2.4m cross-section UNH tow tank; a 10.7m x 3.0m tidal energy test platform which can accommodate turbines up to 1.5m in diameter, for deployments at the UNH-CORE Tidal Energy Test Site in Great Bay Estuary, NH, a sheltered 'nursery site' suitable for intermediate scale tidal energy conversion device testing with peak currents typically above 2 m/s during each tidal cycle. Further, a large boundary layer wind tunnel, the new UNH Flow Physics Facility (W6.0m x H2.7m xL72m) is being used for detailed turbine wake studies, producing data and insight also applicable to MHK turbines in low Froude number deployments. Bi-directional hydrofoils, which perform equally well in either flow direction and could avoid the use of complex and maintenance-intensive yaw or blade pitch mechanisms, are being investigated theoretically, numerically and experimentally. For selected candidate shapes lift, drag, wake, and cavitation inception/desinence are measured. When combined with a cavitation inception model for MHK turbines, this information can be used to prescribe turbine design/operational parameters. Experiments were performed with a 1m diameter and 1m