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Sample records for access drifts test

  1. Test Particles, Test Modes and Drift Turbulence

    SciTech Connect

    Vlad, Madalina; Spineanu, Florin

    2008-10-15

    Strong electrostatic turbulence in magnetically confined plasmas is characterized by trapping or eddying of test particle trajectories produced by the ExB stochastic drift. Trapping is shown to produce non-standard statistics of trajectories: non-Gaussian distribution, memory effects and quasi-coherence. Two types of effects produced by trapping are analyzed. The first type concerns particle and energy transport and consists in very strong nonlinear modification of the diffusion coefficients. Anomalous diffusion regimes are obtained when the other components of the motion (particle collisions, plasma rotation, the motion along the confining magnetic field) do not destroy trajectory eddying. The second type of effects are evidenced by studying test modes on turbulent plasma. We show that trappyng provides the physical mechanism for the inverse cascade observed in drift turbulence.

  2. First quarter chemical borehole studies in the drift scale test

    SciTech Connect

    DeLoach, L., LLNL

    1998-05-19

    The chemistry boreholes of the Drift Scale Test (DST) have been designed to gather geochemical information and assess the impact of thermal perturbations on gas and liquid phases present in pore spaces and fractures within the rock. There are a total of ten boreholes dedicated to these chemical studies. Two arrays of five boreholes each were drilled from the access/observation drift (AOD) in planes which run normal to the heater drift and which are located approximately 15 and 45% of the way along the length of the drift as measured from the bulkhead. The boreholes each have a length of about 40 meters and have been drilled at low angles directed just above or just below the heater plane. In each array, three boreholes are directed at increasingly steeper angles (< 25-) above the line of wing heaters and two are directed at shallow angles below the wing heater plane.

  3. The Yucca Mountain Project drift scale test

    SciTech Connect

    Finley, R.E.; Blair, S.C.; Boyle, W.J.

    1998-06-01

    The Yucca Mountain Project is currently evaluating the coupled thermal-mechanical-hydrological-chemical (TMHC) response of the potential repository host rock through an in situ thermal testing program. A drift scale test (DST) was constructed during 1997 and heaters were turned on in December 1997. The DST includes nine canister-sized containers with thirty operating heaters each located within the heated drift (HD) and fifty wing heaters located in boreholes in both ribs with a total power output of nominally 210kW. A total of 147 boreholes (combined length of 3.3 km) houses most of the over 3700 TMHC sensors connected with 201 km of cabling to a central data acquisition system. The DST is located in the Exploratory Studies Facility in a 5-m diameter drift approximately 50 m in length. Heating will last up to four years and cooling will last another four years. The rock mass surrounding the DST will experience a harsh thermal environment with rock surface temperatures expected to reach a maximum of about 200 C. This paper describes the process of designing the DST. The first 38 m of the 50-m long Heated Drift (HD) is dedicated to collection of data that will lead to a better understanding of the complex coupled TMHC processes in the host rock of the proposed repository. The final 12 m is dedicated to evaluating the interactions between the heated rock mass and cast-in-place (CIP) concrete ground support systems at elevated temperatures. In addition to a description of the DST design, data from site characterization, and a general description of the analyses and analysis approach used to design the test and make pretest predictions are presented. Test-scoping and pretest numerical predictions of one way thermal-hydrologic, thermal-mechanical, and thermal-chemical behaviors have been completed (TRW, 1997a). These analyses suggest that a dry-out zone will be created around the DST and a 10,000 m{sup 3} volume of rock will experience temperatures above 100 C. The HD

  4. Yucca Mountain drift scale test progress report

    SciTech Connect

    Apps, J.; Birkholzer, J.T.; Peterson,J.E.; Sonnenthal, E.; Spycher, N.; Tsang, Y.W.; Williams, K.H.

    1999-01-01

    The Drift Scale Test (DST) is part of the Exploratory Studies Facility (ESF) Thermal Test being conducted underground at the potential high-level nuclear waste repository at Yucca Mountain, Nevada. The purpose of the ESF Thermal Test is to acquire a more in-depth understanding of the coupled thermal, mechanical, hydrological, and chemical processes likely to be encountered in the rock mass surrounding the potential geological repository at Yucca Mountain. These processes are monitored by a multitude of sensors to measure the temperature, humidity, gas pressure, and mechanical displacement, of the rock formation in response to the heat generated by the heaters. In addition to collecting passive monitoring data, active hydrological and geophysical testing is also being carried out periodically in the DST. These active tests are intended to monitor changes in the moisture redistribution in the rock mass, to collect water and gas samples for chemical and isotopic analysis, and to detect microfiacturing due to heating. On December 3, 1998, the heaters in the DST were activated. The planned heating phase of the DST is 4 years, and the cooling phase following the power shutoff will be of similar duration. The present report summarizes interpretation and analysis of thermal, hydrological, chemical, and geophysical data for the first 6 months; it is the first of many progress reports to be prepared during the DST.

  5. Spray drift reduction test method correlation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ASTM Standard E609 Terminology Relating to Pesticides defines drift as “The physical movement of an agrochemical through the air at the time of application or soon thereafter to any non or off target site.” Since there are many commercial tank mix adjuvants designed to reduce spray drift, ASTM esta...

  6. An overview of spray drift reduction testing of spray nozzles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The importance of the development and testing of drift reduction technologies (DRTs) is increasing. Common spray drift reduction technologies include spray nozzles and spray adjuvants. Following draft procedures developed for a DRT program, three spray nozzles were tested under high air speed cond...

  7. THERMAL TEST ALCOVE HEATED DRIFT GROUND SUPPORT ANALYSIS

    SciTech Connect

    S. Bonabian

    1996-10-03

    The main purpose and objective of this analysis is to analyze the stability of the Thermal Test Facility Heated Drift and to design a ground support system. The stability of the Heated Drift is analyzed considering in situ, seismic, and thermal loading conditions. A ground support system is recommended to provide a stable opening for the Heated Drift. This report summarizes the results of the analyses and provides the details of the recommended ground support system for the Heated Drift. The details of the ground support system are then incorporated into the design output documents for implementation in the field.

  8. Validation testing of drift reduction technology testing protocol

    EPA Science Inventory

    A number of pesticide application technologies offer the potential to reduce spray drift from pesticide applications. However, limited information exists on the effectiveness of these technologies in reducing spray drift. Working with a stakeholder technical panel under EPA's Env...

  9. D. phi. vertex drift chamber construction and test results

    SciTech Connect

    Clark, A.R.; Goozen, F.; Grudberg, P.; Klopfenstein, C.; Kerth, L.T.; Loken, S.C.; Oltman, E.; Strovink, M.; Trippe, T.G.

    1991-05-01

    A jet-cell based vertex chamber has been built for the D{O} experiment at Fermilab and operated in a test beam there. Low drift velocity and diffusion properties were achieved using CO{sub 2}(95%)-ethane(5%) at atmospheric pressure. The drift velocity is found to be consistent with (9.74+8.68( E -1.25)) {mu}m/nsec where E is the electric field strength in (kV/cm < E z 1.6 kV/cm.) An intrinsic spatial resolution of 60 {mu}m or better for drift distances greater than 2 mm is measured. The track pair efficiency is estimated to be better than 90% for separations greater than 630 {mu}m. 8 refs., 6 figs., 1 tab.

  10. Drift scale test status report (Chapters 1-9)

    SciTech Connect

    Lin, W., LLNL

    1998-07-01

    The Drift-Scale Test (DST) is one of the thermal tests being conducted in the Exploratory Studies Facility (ESF) at Yucca Mountain, Nevada, site of the potential repository for high-level nuclear waste. One of the DST`s major objectives is to study the coupled thermal-hydrologic-chemical-mechanical (THCM) processes at the potential repository`s horizon. The objectives, test design, and test layouts of the DST are included in a previous test design report. this report present results and analysis of several difference measurements made in the DST by researchers at Lawrence Livermore National Laboratory through the second quarter of the heating phase. Sections 1.1 and 1.2 describe the layout of the DST and the boreholes and instrumentation used to monitor the THCM processes in the rock of associated drifts. Section 2 presents an analysis of temperature data for the test through the end of May 1998. Sections 3 and 4 present results of electrical resistance tomography and neutron logging measurements, respectively. These two sets of measurements are designed to determine the movement of moisture in the test. Results of a series of geochemical measurements made on gas and water samples are presented in Section 5. The purpose of these measurements is to monitor the chemical processes occurring in the DST. Section 6 presents results of thermohydrologic modeling analysis of the test, and Section 7 presents data collected via the laboratory testing for characterization of the hydrologic properties of the rock forming the DST. A brief analysis of barometric pressure and humidity data collected through the end of May 1998 is discussed in Section 8, along with temperature data for the bulkhead. Finally, Section 9 presented an evaluation of sensors used in the DST.

  11. Scale model testing of drogues for free drifting buoys

    NASA Technical Reports Server (NTRS)

    Vachon, W. A.

    1973-01-01

    Instrumented model drogue tests were conducted in a ship model towing tank. The purpose of the tests was to observe and measure deployment and drag characteristics of such shapes as parachutes, crossed vanes, and window shades which may be employed in conjunction with free drifting buoys. Both Froude and Reynolds scaling laws were applied while scaling to full scale relative velocities of from 0 to 0.2 knots. A weighted window shade drogue is recommended because of its performance, high drag coefficient, simplicity, and low cost. Detailed theoretical performance curves are presented for parachutes, crossed vanes, and window shade drogues. Theoretical estimates of depth locking accuracy and buoy-induced dynamic loads pertinent to window shade drogues are presented as a design aid. An example of a window shade drogue design is presented.

  12. Testing the Concept of Drift Shadow at Yucca Mountain, Nevada

    SciTech Connect

    J.B. Paces; L.A. Neymark; T. Ghezzehei; P.F. Dobson

    2006-03-10

    If proven, the concept of drift shadow, a zone of reduced water content and slower ground-water travel time beneath openings in fractured rock of the unsaturated zone, may increase performance of a proposed geologic repository for high-level radioactive waste at Yucca Mountain. To test this concept under natural-flow conditions present in the proposed repository horizon, isotopes within the uranium-series decay chain (uranium-238, uranium-234, and thorium-230, or {sup 238}U-{sup 234}U-{sup 230}Th) have been analyzed in samples of rock from beneath four naturally occurring lithophysal cavities. All samples show {sup 234}U depletion relative to parent {sup 238}U, indicating varying degrees of water-rock interaction over the past million years. Variations in {sup 234}U/{sup 238}U activity ratios indicate that depletion of {sup 234}U relative to {sup 238}U can be either smaller or greater in rock beneath cavity floors relative to rock near cavity margins. These results are consistent with the concept of drift shadow and with numerical simulations of meter-scale spherical cavities in fractured tuff. Differences in distribution patterns of {sup 234}U/{sup 238}U activity ratios in rock beneath the cavity floors are interpreted to reflect differences in the amount of past seepage into lithophysal cavities, as indicated by the abundance of secondary mineral deposits present on the cavity floors.

  13. Testing the concept of drift shadow at Yucca Mountain, Nevada

    USGS Publications Warehouse

    Paces, J.B.; Neymark, L.A.; Ghezzehei, T.; Dobson, P.F.

    2006-01-01

    If proven, the concept of drift shadow, a zone of reduced water content and slower ground-water travel time beneath openings in fractured rock of the unsaturated zone, may increase performance of a proposed geologic repository for high-level radioactive waste at Yucca Mountain, To test this concept under natural-flow conditions present in the proposed repository horizon, isotopes within the uranium-series decay chain (uranium-238, uranium-234, and thorium-230, or 238U-234U-230Th) have been analyzed in samples of rock from beneath four naturally occurring lithophysal cavities. All rock samples show 234U depletion relative to parent 238U indicating varying degrees of water-rock interaction over the past million years. Variations in 234U/238U activity ratios indicate that depletion of 234U relative to 238U can be either smaller or greater in rock beneath cavity floors relative to rock near cavity margins. These results are consistent with the concept of drift shadow and with numerical simulations of meter-scale spherical cavities in fractured tuff. Differences in distribution patterns of 234U/ 238U activity ratios in rock beneath the cavity floors are interpreted to reflect differences in the amount of past seepage into lithophysal cavities, as indicated by the abundance of secondary mineral deposits present on the cavity floors.

  14. Testing the COncept of Drift Shadow with X-Ray Absorption Imaging

    SciTech Connect

    S.J. Altman; A. Forsberg; W. Peplinski; CK. Ho

    2006-04-24

    X-ray absorption imaging experiments and measurements of inflow and outflow distribution provide quantitative and vistial evidence for capillary diversion around a drift and a drift-shadow effect. Test cells were constructed from volcanic tuff with either in-plane (one fracture parallel to the face of the test cell) or multi-fracture (with a grid of fractures perpendicular to the test cell) systems. Tracer solutions were dripped in the fractures at ports along the top of the test cell. Discharge along the bottom boundary and in the drift was monitored. Variables included flow rate and fracture aperture. X-ray absorption imaging allowed for visualization of flow paths through the system. Evidence for capillary diversion and drift shadow include: (1) very small (< 1 %,of inflow in most cases) measured discharge into the drift, (2) discharge less than expected under the drift and discharge greater than expected just beyond the drift, and (3) visualization of the tracer-solution flow path from above the drift, around the drift, and shedding beyond the drift. However, tracer was also observed in a natural fracture under the drift in one system. It is unclear whether these high concentrations are due to diversion around the drift and back under the drift or capillary spreading along the bottom boundary of the test cell. Future experiments will focus on using samples collected directly from Yucca Mountain and minimizing the capillary barrier effects along the lower boundary of the test cells. The implementation of the drift shadow effect, as supported by these experiments, could impact performance of the proposed Yucca Mountain repository.

  15. THE DRIFT SCALE HEATER TEST AT YUCCA MOUNTAIN, NEVADA

    SciTech Connect

    Peters, Mark T.; Boyle, William J.; Datta, Robin N.; Elkins, Ned Z.; Yasek, Robert N.; Wagner, Ralph A.; Weaver, Douglas J.

    1998-01-30

    The Drift Scale Heater Test (DST) is an integral part of the program of testing and studies being conducted by the U.S. Department of Energy to evaluate the suitability of Yucca Mountain, Nevada as a site of a deep geologic repository for the permanent disposal of spent nuclear fuel and high-level nuclear waste. The DST is a large-scale, in situ thermal test to be conducted over nearly a decade in the Exploratory Studies Facility at Yucca Mountain (Figure 1). The overall objective of the DST is to acquire a more indepth understanding of the physical processes that will occur in the rock surrounding the emplaced waste. There are four principal processes of concern: thermal, mechanical, hydrological, and chemical. These processes will be intensified because of the decay heat from the emplaced waste and their interaction or coupling. An understanding of these coupled processes is essential for the assessment of the long-term (over thousands of years) performance of the repository.

  16. Effects of Introduced Materials in the Drift Scale Test

    SciTech Connect

    DeLoach, L; Jones, RL

    2002-01-11

    Water samples previously acquired from superheated (>140 C) zones within hydrological test boreholes of the Drift Scale Test (DST) show relatively high fluoride concentrations (5-66 ppm) and low pH (3.1-3.5) values. In these high temperature regions of the rock, water is present superheated vapor only--liquid water for sampling purposes is obtained during the sampling process by cooling. Based on data collected to date, it is evident that the source of the fluoride and low pH is from introduced man-made materials (Teflon{trademark} and/or Viton{trademark} fluoroelastomer) used in the test. The test materials may contribute fluoride either by degassing hydrogen fluoride (HF) directly to produce trace concentrations of HF gas ({approx}0.1 ppm) in the high temperature steam, or by leaching fluoride in the sampling tubes after condensation of the superheated steam. HF gas is known to be released from Viton{trademark} at high temperatures (Dupont Dow Elastomers L.L.C., Elkton, MD, personal communication) and the sample water compositions indicate near stoichiometric balance of hydrogen ion and fluoride ion, indicating dissolution of HF gas into the aqueous phase. These conclusions are based on a series of water samples collected to determine if the source of the fluoride is from the degradation of materials originally installed to facilitate measurements. Analyses of these water samples show that the source of the fluoride is the introduced materials, that is the Viton{trademark} packers used to isolate test zones and/or Teflon{trademark} tubing used to draw water and steam from the test zones. In particular, water samples collected from borehole (BH) 72 high temperatures ({approx} 170 C) prior to introduction of any Viton{trademark} or Teflon{trademark} show pH Values (4.8 to 5.5) and fluoride concentrations well below 1 ppm over a period of six months. These characteristics are typical of condensing DST steam that contains only some dissolved carbon dioxide generated

  17. Spray drift reduction evaluations of spray nozzles using a standardized testing protocol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development and testing of drift reduction technologies has come to the forefront of application research in the past few years in the United States. Drift reduction technologies (DRTs) can be spray nozzles, sprayer modifications, spray delivery assistance, spray property modifiers (adjuvants),...

  18. A Stepwise Test Characteristic Curve Method to Detect Item Parameter Drift

    ERIC Educational Resources Information Center

    Guo, Rui; Zheng, Yi; Chang, Hua-Hua

    2015-01-01

    An important assumption of item response theory is item parameter invariance. Sometimes, however, item parameters are not invariant across different test administrations due to factors other than sampling error; this phenomenon is termed item parameter drift. Several methods have been developed to detect drifted items. However, most of the…

  19. Test particle study of ion transport in drift type turbulence

    SciTech Connect

    Vlad, M.; Spineanu, F.

    2013-12-15

    Ion transport regimes in drift type turbulence are determined in the frame of a realistic model for the turbulence spectrum based on numerical simulations. The model includes the drift of the potential with the effective diamagnetic velocity, turbulence anisotropy, and dominant waves. The effects of the zonal flow modes are also analyzed. A semi-analytical method that is able to describe trajectory stochastic trapping or eddying is used for obtaining the transport coefficients as function of the parameters of the turbulence. Analytical approximations of the transport coefficients are derived from the results. They show the transition from Bohm to gyro-Bohm scaling as plasma size increases in very good agreement with the numerical simulations.

  20. Radiation tests of the silicon drift detectors for LOFT

    NASA Astrophysics Data System (ADS)

    Del Monte, E.; Azzarello, P.; Bozzo, E.; Bugiel, S.; Diebold, S.; Evangelista, Y.; Kendziorra, E.; Muleri, F.; Perinati, E.; Rachevski, A.; Zampa, G.; Zampa, N.; Feroci, M.; Pohl, M.; Santangelo, A.; Vacchi, A.

    2014-07-01

    During the three years long assessment phase of the LOFT mission, candidate to the M3 launch opportunity of the ESA Cosmic Vision programme, we estimated and measured the radiation damage of the silicon drift detectors (SDDs) of the satellite instrumentation. In particular, we irradiated the detectors with protons (of 0.8 and 11 MeV energy) to study the increment of leakage current and the variation of the charge collection efficiency produced by the displacement damage, and we "bombarded" the detectors with hypervelocity dust grains to measure the effect of the debris impacts. In this paper we describe the measurements and discuss the results in the context of the LOFT mission.

  1. First-quarter report of neutron logging during the heating phase of the drift-scale test

    SciTech Connect

    Lin, W., LLNL

    1998-04-01

    The Drift-Scale Test (DST) is one of the thermal tests being conducted in the Exploratory Studies Facility (ESF). One of the purposes of the DST is to study, at the ESF, the coupled thermal- mechanical- hydrologic-chemical (TMHC) processes at the repository horizon of the potential high-level nuclear waste repository at Yucca Mountain, Nevada. The objectives, the test design, and the test layouts of the DST are included in the test design report by the Civilian Radioactive Waste Management System Management and Operation (CRWMS M&O) contractors. The configuration of the DST includes a declining observation drift driven mostly east and downward from main tunnel in the ESF at approximately 2.827 km from the north portal. The downward slope of the observation drift (11.5% to 14.0%) ensures a minimum of 10 m of middle nonlithophysal Topopah Spring tuff as the overburden for the DST. The length of the observation drift is approximately 136 m. At the elevation of the DST crown (nominally 10 m below the upper extent of the middle nonlithophysal Topopah Spring tuff), the connecting drift breaks out to the north from the observation drift 136 m from the main tunnel of the ESF. The connecting drift extends approximately 40 m to the north from the observation drift. A heater drift breaks out westward from the connecting drift at approximately 30 m from the observation drift. The heater drift consists of an 11-m-long entry, which includes a plate-loading niche, and a 47-m-long heated drift. The nominal diameter of the drifts is 5 m. The detail configuration of the DST, including diagrams showing the drift and borehole layout, is included in the test design report by CRWMS M&O contractors.

  2. The Effect of Anchor Test Construction on Scale Drift

    ERIC Educational Resources Information Center

    Antal, Judit; Melican, Gerald; Proctor, Thomas; Wiley, Andrew

    2010-01-01

    Presented at the Annual Meeting of National Council on Measurement in Education (NCME) in 2010. The focus of the research is to investigate the effect of applying the Sinharay & Holland (2007) midi-test idea for building anchor tests to an on-going testing program with a series of versions of the test and comparing these results to the more…

  3. Hardware Testing of the BaBar Drift Chamber Electronics Upgrade (SULI paper)

    SciTech Connect

    Littlejohn, Bryce; Chu, Yiwen; Wiik, Liv; /SLAC

    2006-01-04

    The BaBar drift chamber provides position, timing, and dE/dx measurements for charged decay products of the {Upsilon}(4S) resonance at 10.58 GeV. Increasing data collection rates stemming from higher PEP II luminosities and background have highlighted dead time problems in the drift chamber's data acquisition system. A proposed upgrade, called Phase II, aims to solve the problem with the introduction of rewritable, higher-memory firmware in the DAQ front-end electronics that lowers dataflow through the system. After fabrication, the new electronics components were tested to ensure proper function and reliability before installation in the detector. Some tests checked for successful operation of individual components, while others operated entire sections of the upgraded system in a mockup drift chamber environment. This paper explains the testing process and presents results regarding performance of the upgrade electronics.

  4. Test stands for the Central Drift Chamber front end hybrid in the Stanford Linear Collider Detector

    SciTech Connect

    Lo, C.C.; Yim, A.K.

    1987-10-01

    The Central Drift Chamber (CDC) of the SLAC Linear Collider Detector (SLD) uses 1280 front end electronic hybrid modules. Each of these modules contains over 450 components and performs numerous functions. This paper describes the four test stands for production and detailed circuit characterizations of these hybrids. Descriptions and performance of some of the important functions of the test systems will be presented here.

  5. The Effect of Anchor Test Construction on Scale Drift

    ERIC Educational Resources Information Center

    Antal, Judit; Proctor, Thomas P.; Melican, Gerald J.

    2014-01-01

    In common-item equating the anchor block is generally built to represent a miniature form of the total test in terms of content and statistical specifications. The statistical properties frequently reflect equal mean and spread of item difficulty. Sinharay and Holland (2007) suggested that the requirement for equal spread of difficulty may be too…

  6. Geographic variation in advertisement calls of a Microhylid frog - testing the role of drift and ecology.

    PubMed

    Lee, Ko-Huan; Shaner, Pei-Jen L; Lin, Yen-Po; Lin, Si-Min

    2016-05-01

    Acoustic signals for mating are important traits that could drive population differentiation and speciation. Ecology may play a role in acoustic divergence through direct selection (e.g., local adaptation to abiotic environment), constraint of correlated traits (e.g., acoustic traits linked to another trait under selection), and/or interspecific competition (e.g., character displacement). However, genetic drift alone can also drive acoustic divergence. It is not always easy to differentiate the role of ecology versus drift in acoustic divergence. In this study, we tested the role of ecology and drift in shaping geographic variation in the advertisement calls of Microhyla fissipes. We examined three predictions based on ecological processes: (1) the correlation between temperature and call properties across M. fissipes populations; (2) the correlation between call properties and body size across M. fissipes populations; and (3) reproductive character displacement (RCD) in call properties between M. fissipes populations that are sympatric with and allopatric to a congener M. heymonsi. To test genetic drift, we examined correlations among call divergence, geographic distance, and genetic distance across M. fissipes populations. We recorded the advertisement calls from 11 populations of M. fissipes in Taiwan, five of which are sympatrically distributed with M. heymonsi. We found geographic variation in both temporal and spectral properties of the advertisement calls of M. fissipes. However, the call properties were not correlated with local temperature or the callers' body size. Furthermore, we did not detect RCD. By contrast, call divergence, geographic distance, and genetic distance between M. fissipes populations were all positively correlated. The comparisons between phenotypic Q st (P st) and F st values did not show significant differences, suggesting a role of drift. We concluded that genetic drift, rather than ecological processes, is the more likely

  7. Tests of a single-wire drift chamber for possible use in low intensity beams

    SciTech Connect

    Haggerty, H.

    1986-02-01

    A single cell drift chamber with two dimensional readout has been evaluated as a candidate for reliable and inexpensive momentum tagging of low intensity calibration beams. Charges induced on shaped cathode pads allow a measurement of the coordinate parallel to the wire, while the drift time allows a measurement of the coordinate perpendicular to the wire. Two chamber orientations were used during the tests. In one the chambers were arranged with their wires parallel. In this case the intrinsic resolution of the chambers was measured; the top and bottom cells were used to define a track coordinate and this was compared to the coordinate in the middle chamber. To see if either of the two coordinate measurements is linear in real space, the chambers were rearranged to the second orientation, with the middle chamber rotated 90/sup 0/. The drift time was plotted against the charge ratio. The conclusion drawn from this study is that while the drift time measurement has adequate resolution, the charge ratio measurement is not a viable option for beam line use. (LEW)

  8. Generic Verification Protocol for Testing Pesticide Application Spray Drift Reduction Technologies for Row and Field Crops (Version 1.4)

    EPA Science Inventory

    This generic verification protocol provides a detailed method for conducting and reporting results from verification testing of pesticide application technologies. It can be used to evaluate technologies for their potential to reduce spray drift, hence the term “drift reduction t...

  9. Test Access & Modification for Individuals with Disabilities.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Office of Vocational Rehabilitation.

    This guide is intended to increase access for individuals with disabilities to local, state (New York), and national testing programs, as well as facilitate the consistent provision of modifications necessary to allow these individuals to demonstrate their knowledge and abilities. Ten modules cover the following topics: (1) federal and state…

  10. Thermohydrologic Modeling of the Drift Scale Test in Partially Saturated Fractured Tuff at Yucca Mountain, Nevada

    NASA Astrophysics Data System (ADS)

    Lee, K. H.; Buscheck, T. A.; Sun, Y.; Glascoe, L. G.; Gansemer, J.

    2003-12-01

    Results of thermohydrologic modeling of the Drift Scale Test (DST) at Yucca Mountain show good agreement with field temperatures and liquid phase saturation during the heating as well as the cooling phases of the test. The DST is an ongoing large-scale thermal field test conducted by the US Department of Energy as part of the characterization of Yucca Mountain as a potential site of a geologic repository for high-level nuclear waste. The test location is 250 m below the ground surface, in fractured nonlithophysal Topopah Spring tuff, which is one of the host-rock units for the potential repository. The DST is one of a series of field-scale thermohydrologic tests designed to help investigators better understand the coupled thermohydrologic-mechanical-chemical processes that would occur in the host rock in response to the radioactive heat of decay from emplaced waste packages. The tests also provide data for the calibration and validation of numerical models used to analyze the thermohydrologic response of the near-field host rock and Engineered Barrier System (EBS). The rock was heated by nine floor heaters, placed along a 47.5-meter long heated drift, and arrays of wing heaters installed in horizontal boreholes on either side of the drift. A bulkhead separates the HD from the unheated section of the drift. Peak heater power during the heating phase was about 52 kW for the floor heaters and 135 kW for the wing heaters. The rock was heated for 4.1 years before all heaters were turned off on January 14, 2002. Monitoring of the cool-down phase is expected to last for at least four years. Using the NUFT code and the dual-permeability approach to representing fracture-matrix interaction, we utilize a half-symmetry model to simulate the thermohydrologic response of the rock to a heating and cooling cycle. The primary goals of the analysis were to study the heat-flow mechanisms and water redistribution patterns in the boiling and sub-boiling zones, and to compare model

  11. ACCESS: Design, Strategy, and Test Performance

    NASA Astrophysics Data System (ADS)

    Kaiser, Mary Elizabeth; Morris, M. J.; McCandliss, S. R.; Rauscher, B. J.; Kimble, R. A.; Kruk, J. W.; Wright, E. L.; Pelton, R. S.; Feldman, P. D.; Moos, H. W.; Riess, A. G.; Benford, D. J.; Foltz, R.; Gardner, J. P.; Mott, D. B.; Wen, Y.; Woodgate, B. E.; Bohlin, R.; Deustua, S. E.; Dixon, W. V.; Sahnow, D. J.; Kurucz, R. L.; Lampton, M.; Perlmutter, S.

    2013-01-01

    Improvements in the astrophysical flux scale are needed to answer fundamental scientific questions ranging from cosmology to stellar physics. In particular, the precise calibration of the flux scale across the visible-NIR bandpass is fundamental to the precise determination of dark energy parameters based on SNeIa photometry. ACCESS, Absolute Color Calibration Experiment for Standard Stars, is a series of rocket-borne sub-orbital missions and ground-based experiments that will enable improvements in the precision of the astrophysical flux scale through the transfer of absolute laboratory detector standards from the National Institute of Standards and Technology (NIST) to a network of stellar standards with a calibration accuracy of 1% and a spectral resolving power of 500 across the 0.35 to 1.7 micron bandpass. The telescope is a Dall-Kirkham Cassegrain with a 15.5-inch primary. The spectrograph is a Rowland circle design, with the grating operating as a low order (m=1-4) echelle, a Fery prism provides cross dispersion, and a HST/WFC3 heritage HAWAII-1R HgCdTe detector is used across the full spectral bandpass. The telescope mirrors have received their flight coatings. The flight detector and detector spare have been integrated with their electronics and flight mount. The controller electronics have been flight qualified. Vibration testing to launch loads and thermal vacuum testing of the detector, mount, and housing have been performed. Detector characterization testing is in progress (Morris et al.). Fabrication, integration, and automation of the ground-based calibration subsystems are also in progress. The ACCESS design, calibration strategy, and ground-based integration and test results will be presented. Launch is expected this year. NASA sounding rocket grant NNX08AI65G and DOE DE-FG02-07ER41506 support this work.

  12. Coupled THM Simulations of the Drift Scale Test at Yucca Mountain

    SciTech Connect

    Blair, S C; Carlson, S R; Lee, K; Wagoner, J L

    2002-03-08

    This paper presents a coupled thermal-hydrological-mechanical (THM) analysis of the Drift Scale Test (DST) conducted at Yucca Mountain, Nevada. The DST is a large-scale, long-term thermal test designed to investigate coupled thermal-mechanical-hydrological-chemical behavior in a fractured, welded tuff rock mass in support of nuclear waste isolation efforts. The model used for this analysis utilizes temperature distributions predicted by a thermal-hydrological code as input to a distinct element thermal mechanical code. This paper presents a brief discussion of the test and the coupled model, followed by comparison of predicted and measured displacements. Results show that the model predicts the trend and magnitude of the displacements observed in a cross section monitored in the test through four years of heating. Maximum principal stress levels of 60 MPa are predicted in the crown and floor of the heated drift (HD) after 4 years of heating. Comparison of predicted and observed displacements shows that the model closely predicts vertical displacement above the HD and provides a good estimate of horizontal displacement perpendicular to the HD. These results indicate that a thermal expansion coefficient of 9e-6/{Lambda}C is generally appropriate for the rockmass forming this test. Normal displacements on joints in the cross section examined here show opening of up to 2mm on subvertical fractures in regions above and below the HD after 4 years of heating. These fractures do not close upon cooldown, indicating that some permanent enhancement of vertical fracture permeability may occur.

  13. Remotely accessible laboratory for MEMS testing

    NASA Astrophysics Data System (ADS)

    Sivakumar, Ganapathy; Mulsow, Matthew; Melinger, Aaron; Lacouture, Shelby; Dallas, Tim E.

    2010-02-01

    We report on the construction of a remotely accessible and interactive laboratory for testing microdevices (aka: MicroElectroMechancial Systems - MEMS). Enabling expanded utilization of microdevices for research, commercial, and educational purposes is very important for driving the creation of future MEMS devices and applications. Unfortunately, the relatively high costs associated with MEMS devices and testing infrastructure makes widespread access to the world of MEMS difficult. The creation of a virtual lab to control and actuate MEMS devices over the internet helps spread knowledge to a larger audience. A host laboratory has been established that contains a digital microscope, microdevices, controllers, and computers that can be logged into through the internet. The overall layout of the tele-operated MEMS laboratory system can be divided into two major parts: the server side and the client side. The server-side is present at Texas Tech University, and hosts a server machine that runs the Linux operating system and is used for interfacing the MEMS lab with the outside world via internet. The controls from the clients are transferred to the lab side through the server interface. The server interacts with the electronics required to drive the MEMS devices using a range of National Instruments hardware and LabView Virtual Instruments. An optical microscope (100 ×) with a CCD video camera is used to capture images of the operating MEMS. The server broadcasts the live video stream over the internet to the clients through the website. When the button is pressed on the website, the MEMS device responds and the video stream shows the movement in close to real time.

  14. Commissioning of the first drift tube linac module in the Ground Test Accelerator

    SciTech Connect

    Johnson, K.F.; Sander, O.R.; Atkins, W.H.; Bolme, G.O.; Bowling, S.; Cole, R.; Connolly, R.; Denney, P.; Erickson, J.; Gilpatrick, J.D.; Ingalls, W.B.; Kersteins, D.; Kraus, R.; Lysenko, W.P.; McMurry, D.; Mottershead, C.T.; Power, J.; Rose, C.; Rusthoi, D.P.; Sandoval, D.P.; Schneider, J.D.; Smith, M.; Vaughn, G.; Wadlinger, E.A.; Weiss, R.; Yuan, V.

    1993-06-01

    The Ground Test Accelerator (GTA) has the objective of verifying much of the technology required for producing high-brightness, high-current H{sup {minus}} beams. GTA commissioning is staged to verify the beam-dynamics design of each major accelerator component as it is brought on-line. The major components are the 35-keV H{sup {minus}} injector, the 2.5-MeV radio-frequency quadrupole (RFQ), the intertank matching section (IMS), the 3.2 MeV first 2{beta}{lambda} drift tube linac (DTL-1) module, and the 24-MeV GTA with 10 DTL modules. Results from the DTL-1 beam experiments will be presented.

  15. The central drift chamber for the D0 experiment: Design, construction and test

    SciTech Connect

    Behnke, T.

    1989-08-01

    A cylindrical drift chamber has been designed and built at the State University of New York at Stony Brook. This chamber is to be installed in the D0 detector which is being completed at the Fermi National Accelerator. In this dissertation the design, construction and testing of this chamber are described. The characteristic features of this chamber are cells formed by solid walls and a modular structure. Much discussion is given to the performance of and results from a chamber made from three final modules which was installed in the D0 interaction region during the 1988/1989 collider run. Using this chamber proton anti-proton interactions were measured at the D0 interaction point.

  16. Ground Control for Non-Emplacement Drifts for LA

    SciTech Connect

    D. Tang

    2004-02-26

    The purpose of this calculation is to analyze the stability of repository non-emplacement drifts during the preclosure period, and to provide a final ground support method for non-emplacement drifts for the License Application (LA). This calculation will provide input for the development of LA documents. The scope of this calculation is limited to the non-emplacement drifts including access mains, ramps, exhaust mains, turnouts, intersections between access mains and turnouts, and intersections between exhaust mains and emplacement drifts, portals, TBM launch chambers, observation drift and test alcove in the performance confirmation (PC) facilities, etc. The calculation is limited to the non-emplacement drifts subjected to a combined loading of in-situ stress, seismic stress, and/or thermal stress. Other effects such as hydrological and chemical effects are not considered in this analysis.

  17. Influence of heat flow on drift closure during Climax granite spent-fuel test: measurements and calculations

    SciTech Connect

    Butkovich, T.R.; Yow, J.L. Jr.; Montan, D.N.

    1982-09-08

    Measurements of drift closure caused by the thermal load have been made routinely during the Spent Fuel Test in Climax granite since about six weeks after emplacement of the fuel. Horizontal and vertical closure was measured with a manually operated tape extensometer at various locations along the lengths of the drifts. Average closures ranged from 0 to 0.6 mm, horizontal and vertical, out to about 2.2 years since the start of the test. At the same time, displacements from the thermal loads were measured with rod extensometers emplaced to measure relative displacements between hole collars and anchor points in holes drilled from two parallel heater drifts. These data are compared with thermo-elastic finite element calculations which utilized measured properties of the Climax granite. The calculations show that more than half of the closures occur between fuel installation and the first closure measurement. The comparisons show that the results track each other, in that where closure followed by dilation is measured, the calculations also show this effect. The agreement is excellent, considering the averaged measured closures remain within 30% of the total calculated drift closures and the extremely small magnitude of the relative displacements (0.5 mm), measured or calculated.

  18. Method and apparatus for globally-accessible automated testing

    DOEpatents

    Layne, Scott P.; Beugelsdijk, Tony J.

    1998-01-01

    A method and apparatus for sharing integrated testing services with a plurality of autonomous remote clients is disclosed. In the disclosed method, in response to an access request message, a process controller transmits an access enabling message to the remote client. The access enabling message includes instructions performable by a remote client to generate test equipment commands. A process controller interprets and transforms these commands into automated test instrument suite commands, which are provided to laboratory modules to perform the indicated tests. Test data results are then obtained and transmitted to the remote client.

  19. 9. ENGINE TEST CELL BUILDING INTERIOR. CELL ACCESS ELEVATOR, CELLS ...

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

    9. ENGINE TEST CELL BUILDING INTERIOR. CELL ACCESS ELEVATOR, CELLS 2 AND 4, BASEMENT LEVEL. LOOKING SOUTHEAST. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA

  20. ICP measurement accuracy: the effect of temperature drift. Design of a laboratory test for assessment of ICP transducers.

    PubMed

    Morgalla, M H; Mettenleiter, H; Katzenberger, T

    1999-01-01

    Intracranial pressure (ICP) monitoring has become the mainstay of multimodal neuromonitoring of comatous patients after head injury. In the presence of rising ICP and faced with pressures, difficult to control, aggressive measures, such as hypothermia may be used. The ICP readings should not be influenced by temperature changes. A laboratory test was designed to simulate temperature variations between 20 degrees C and 45 degrees C at different pressure levels under physiological conditions. Five types of transducers were examined: Epidyn Braun Melsungen, ICT/B-Titan Gaeltec, Camino-OLM-110-4B, Codman MicroSensor ICP-Transducer, Neurovent ICP transducer Rehau Ag+Co. Tests were performed at 6 different pressure levels between 0 mmHg and 50 mmHg. The results show very low drifts of less than 0.15 mmHg degree C-1 for Codman, Epidyn and Neurovent. Gaeltec and Camino exhibited higher drifts of 0.18 mmHg and 0.2 mmHg degree C-1 respectively. Within the temperature range from 35 degrees C to 42 degrees C all probes tested show insignificant temperature drift. Whether these results also apply to other types of transducers needs further evaluation. Problems and requirements related to the design of a laboratory test for the in vitro assessment of ICP transducers are discussed in detail. PMID:10202697

  1. Dike/Drift Interactions

    SciTech Connect

    E.S. Gaffney

    2003-10-08

    This report documents the model of events associated with a potential intrusion of magma from a volcanic dike into a drift or drifts in the Yucca Mountain Nuclear Waste Repository. The following topics are included in this report: (1) A discussion of dike propagation, which provides the basis for describing the path that a representative dike, or swarm of dikes, would follow during an event. (2) A discussion of magma flow, which evaluates the interaction at the junction of the propagating dike with the drift and the movement of magmatic products into and down drifts and, potentially, through a drift to the surface by way of access drift or a secondary dike opened up along the drift. (3) A discussion of gas flow and conductive cooling of a magma-filled drift, describing how an adjacent drift that has not been intersected by a dike could be affected by post-intrusion phenomena. Note that a gas flow analysis is also addressed in ''Igneous Intrusion Impacts on Waste Form and Waste Packages'' (BSC 2003 [DIRS 161810]), and those results are consistent with the results presented in this report.

  2. Calculated and measured drift closure during the spent-fuel test in Climax granite

    SciTech Connect

    Yow, J.L. Jr.; Butkovich, T.R.

    1982-04-01

    Horizontal and vertical measurements of drift closures have been made with a manually operated tape extensometer since about 6 weeks after the emplacement of the spent fuel at various locations along the length of the drifts. The averaged closures are less than 0.6 mm from the onset of measurements through about two years after the spent fuel emplacement. These results have been compared with thermo-elastic finite element calculations using measured medium properties. The comparisons show that most of the closure of the drifts occurred between the time the spent fuel was emplaced and the time of first measurement. The comparisons show that the results track each other, in that where closure followed by dilation is measured, the calculations also show this effect. The agreement is excellent, although where closures of less than 0.2 mm are measured the comparison with calculations is limited by measurement reproducability. Once measurements commenced the averaged measured closures remain to within 30% of the calculated total closure in each drift. 9 figures, 1 table.

  3. Evaluation of a proposed drift reduction technology high-speed wind tunnel testing protocol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The U.S. Environmental Protection Agency (EPA) has initiated the development of protocols for for measuring spray drift reduction technologies (DRTs) related to the application of agricultural protection chemicals. The DRT Program is an EPA-led initiative program to “achieve improved environmental ...

  4. Redshift-Drift as a Test for Discriminating Between Decelerating Inhomogeneous and Accelerating Universe Models

    NASA Astrophysics Data System (ADS)

    Mishra, Priti; Célérier, Marie-Noëlle Singh, Tejinder P.

    2015-01-01

    Exact inhomogeneous solutions of Einstein's equations have been used in the literature to build models reproducing the cosmological data without dark energy. However, owing to the degrees of freedom pertaining to these models, it is necessary to get rid of the degeneracy often exhibited by the problem of distinguishing between them and accelerating universe models. We give an overview of redshift drift in inhomogeneous cosmologies, and explain how it serves to this purpose. One class of models which fits the data is the Szekeres Swiss-cheese class where non-spherically symmetric voids exhibit a typical size of about 400 Mpc. We present our calculation of the redshift drift in this model, and compare it with the results obtained by other authors for alternate scenarios.

  5. Impact of genetic drift on access and benefit sharing under the Nagoya protocol: The case of the Meishan pig

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Convention on Biological Diversity developed the Nagoya Protocol (NP) on access and benefit sharing (ABS) for international exchange of genetic resources. Concerns are NP will impose new costs for exchanging livestock genetic resources and interfere with commonly used private treaty contracts. N...

  6. Using Operational Analysis to Improve Access to Pulmonary Function Testing.

    PubMed

    Ip, Ada; Asamoah-Barnieh, Raymond; Bischak, Diane P; Davidson, Warren J; Flemons, W Ward; Pendharkar, Sachin R

    2016-01-01

    Background. Timely pulmonary function testing is crucial to improving diagnosis and treatment of pulmonary diseases. Perceptions of poor access at an academic pulmonary function laboratory prompted analysis of system demand and capacity to identify factors contributing to poor access. Methods. Surveys and interviews identified stakeholder perspectives on operational processes and access challenges. Retrospective data on testing demand and resource capacity was analyzed to understand utilization of testing resources. Results. Qualitative analysis demonstrated that stakeholder groups had discrepant views on access and capacity in the laboratory. Mean daily resource utilization was 0.64 (SD 0.15), with monthly average utilization consistently less than 0.75. Reserved testing slots for subspecialty clinics were poorly utilized, leaving many testing slots unfilled. When subspecialty demand exceeded number of reserved slots, there was sufficient capacity in the pulmonary function schedule to accommodate added demand. Findings were shared with stakeholders and influenced scheduling process improvements. Conclusion. This study highlights the importance of operational data to identify causes of poor access, guide system decision-making, and determine effects of improvement initiatives in a variety of healthcare settings. Importantly, simple operational analysis can help to improve efficiency of health systems with little or no added financial investment. PMID:27445545

  7. Using Operational Analysis to Improve Access to Pulmonary Function Testing

    PubMed Central

    Ip, Ada; Asamoah-Barnieh, Raymond; Bischak, Diane P.; Davidson, Warren J.; Flemons, W. Ward; Pendharkar, Sachin R.

    2016-01-01

    Background. Timely pulmonary function testing is crucial to improving diagnosis and treatment of pulmonary diseases. Perceptions of poor access at an academic pulmonary function laboratory prompted analysis of system demand and capacity to identify factors contributing to poor access. Methods. Surveys and interviews identified stakeholder perspectives on operational processes and access challenges. Retrospective data on testing demand and resource capacity was analyzed to understand utilization of testing resources. Results. Qualitative analysis demonstrated that stakeholder groups had discrepant views on access and capacity in the laboratory. Mean daily resource utilization was 0.64 (SD 0.15), with monthly average utilization consistently less than 0.75. Reserved testing slots for subspecialty clinics were poorly utilized, leaving many testing slots unfilled. When subspecialty demand exceeded number of reserved slots, there was sufficient capacity in the pulmonary function schedule to accommodate added demand. Findings were shared with stakeholders and influenced scheduling process improvements. Conclusion. This study highlights the importance of operational data to identify causes of poor access, guide system decision-making, and determine effects of improvement initiatives in a variety of healthcare settings. Importantly, simple operational analysis can help to improve efficiency of health systems with little or no added financial investment. PMID:27445545

  8. A simple model for testing the effects of gravity-wave-produced vertical oscillations of scattering irregularities on spaced-antenna, horizontal drift measurements

    NASA Technical Reports Server (NTRS)

    Meek, C. E.; Reid, I. M.

    1984-01-01

    It has been suggested that the velocities produced by the spaced antenna partial-reflection drift experiment may constitute a measure of the vertical oscillations due to short-period gravity waves rather than the mean horizontal flow. The contention is that the interference between say two scatterers, one of which is traveling upward, and the other down, will create a pattern which sweeps across the ground in the direction (or anti-parallel) of the wave propagation. Since the expected result, viz., spurious drift directions, is seldom, if ever, seen in spaced antenna drift velocities, this speculation is tested in an atmospheric model.

  9. Test/QA plan for the validation of the verification protocol for high speed pesticide spray drift reduction technologies for row and field crops

    EPA Science Inventory

    This test/QA plan for evaluation the generic test protocol for high speed wind tunnel, representing aerial application, pesticide spray drift reduction technologies (DRT) for row and field crops is in conformance with EPA Requirements for Quality Assurance Project Plans (EPA QA/R...

  10. Test/QA plan for the validation of the verification protocol for low speed pesticide spray drift reduction technologies for row and field crops

    EPA Science Inventory

    This test/QA plan for evaluation the generic test protocol for high speed wind tunnel, representing aerial application, pesticide spray drift reduction technologies (DRT) for row and field crops is in conformance with EPA Requirements for Quality Assurance Project Plans (EPA QA/R...

  11. A system to test the effects of materials on the electron drift lifetime in liquid argon and observations on the effect of water

    SciTech Connect

    Andrews, R.; Jaskierny, W.; Jostlein, H.; Kendziora, C.; Pordes, S.; Tope, T.; /Fermilab

    2009-07-01

    A materials test system (MTS) has been developed at FNAL to assess the suitability of materials for use in a large liquid argon time projection chamber. During development of the MTS, it was noted that controlling the cryostat pressure with a 'raining' condenser reduced the electron drift lifetime in the liquid argon. The effect of condensing has been investigated using a series of passive materials to filter the condensate. We report the results of these studies and of tests on different candidate materials for detector construction. The inferred reduction of electron drift lifetime by water concentrations in the parts per trillion is of particular interest.

  12. Drift Scale THM Model

    SciTech Connect

    J. Rutqvist

    2004-10-07

    drift to transport any exposed radionuclides out of the drift to the groundwater below, and eventually to people within the accessible environment. Absent sufficient water, radionuclides cannot be transported and there would be no significant health effect on people, even if radioactive waste containers were damaged or corroded to such an extent that radionuclides were exposed to water.

  13. Accessibility Theory for Enhancing the Validity of Test Results for Students with Special Needs

    ERIC Educational Resources Information Center

    Beddow, Peter A.

    2012-01-01

    In the arena of educational testing, accessibility refers to the degree to which students are given the opportunity to participate in and engage a test. Accessibility theory is a model for examining the interactions between the test-taker and the test itself and defining how they may decrease some students' access to the test event, ultimately…

  14. Uncertainties in coupled thermal-hydrological processes associated with the Drift Scale Test at Yucca Mountain, Nevada.

    PubMed

    Mukhopadhyay, S; Tsang, Y W

    2003-01-01

    Understanding thermally driven coupled hydrological, mechanical, and chemical processes in unsaturated fractured tuff is essential for evaluating the performance of the potential radioactive waste repository at Yucca Mountain, Nevada. The Drift Scale Test (DST), intended for acquiring such an understanding of these processes, has generated a huge volume of temperature and moisture redistribution data. Sophisticated thermal-hydrological (TH) conceptual models have yielded a good fit between simulation results and those measured data. However, some uncertainties in understanding the TH processes associated with the DST still exist. This paper evaluates these uncertainties and provides quantitative estimates of the range of these uncertainties. Of particular interest for the DST are the uncertainties resulting from the unmonitored loss of vapor through an open bulkhead of the test. There was concern that the outcome from the test might have been significantly altered by these losses. Using alternative conceptual models, we illustrate that predicted mean temperatures from the DST are within 1 degrees C of the measured mean temperatures through the first 2 years of heating. The simulated spatial and temporal evolution of drying and condensation fronts is found to be qualitatively consistent with measured saturation data. Energy and mass balance computation shows that no more than 13% of the input energy is lost because of vapor leaving the test domain through the bulkhead. The change in average saturation in fractures is also relatively small. For a hypothetical situation in which no vapor is allowed to exit through the bulkhead, the simulated average fracture saturation is not qualitatively different enough to be discerned by measured moisture redistribution data. This leads us to conclude that the DST, despite the uncertainties associated with open field testing, has provided an excellent understanding of the TH processes. PMID:12714312

  15. Test report: Low cost access and efficient use of TDRSS

    NASA Technical Reports Server (NTRS)

    Horan, S.

    1996-01-01

    In order to develop new ways to increase the number of users taking advantage of NASA's Space Network for space-to-ground communications links, researchers at New Mexico State University (NMSU) developed a technique for using non-gimballed antennas for accessing a Tracking and Data Relay Satellite (TDRS) within the Space Network (SN). This concept would allow spin-stabilized satellites to access one of the TDRS spacecraft in the SN constellation as the user satellite sweeps past the TDRS position as the satellite approaches either its ascending or descending node if this node is relatively close to the TDRS subsatellite point. ne research team from NMSU developing this concept proposed to NASA the use of the Extreme Ultra Violet Explorer (EUVE) to test this concept on orbit. EUVE differs from the desired satellite configuration in that EUVE has a relatively high-gain parabolic antenna and, most importantly, EUVE has an inertially-stabilized attitude control system while the concept to be tested was for a spin-stabilized satellite. We believed that these limitations would not affect the basic proof-of-concept test we were trying to achieve. With the approval and coordination of NASA, a total of six satellite passes through the West TDRS were requested and the necessary equipment configured for data collection at the Second TDRS Ground Terminal (STGT), also known as Danzante, at the White Sands Complex.

  16. 10 CFR 26.65 - Pre-access drug and alcohol testing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Pre-access drug and alcohol testing. 26.65 Section 26.65... § 26.65 Pre-access drug and alcohol testing. (a) Purpose. This section contains pre-access testing... days. If an individual has negative results from drug and alcohol tests that were conducted under...

  17. A Conceptual and Numerical Model for Thermal-Hydrological-Chemical Processes in the Yucca Mountain Drift Scale Test

    SciTech Connect

    Sonnenthal, Eric L.; Spycher, Nicolas F.; Conrad, Mark; Apps, John

    2003-07-01

    A numerical model was developed to predict the coupled thermal, hydrological, and chemical (THC) processes accompanying the Drift Scale Test (DST) at Yucca Mountain, NV. The DST has been closely monitored through the collection of gas, water, and mineral samples as well as thermal, hydrological, and mechanical measurements. A two-dimensional dual permeability model was developed to evaluate multiphase, multicomponent, reaction-transport processes in the fractured tuff. Comparisons between results using the TOUGHREACT code and measured water (e.g., pH, SiO2(aq), Na+, K+) and gas (CO2) compositions show that the model captures the chemical evolution in the DST. Non-reactive aqueous species (e.g., Cl) show strong dilution in fracture waters, indicating little fracture-matrix interaction. Silica concentrations are higher than in the initial pore water and show a trend of increasing reaction with fracture-lining silicates at higher temperatures. The narrow precipitation zone of predominantly amorphous silica observed above the heaters was also captured.

  18. Geographic variation in the songs of neotropical singing mice: testing the relative importance of drift and local adaptation.

    PubMed

    Campbell, Polly; Pasch, Bret; Pino, Jorge L; Crino, Ondi L; Phillips, Molly; Phelps, Steven M

    2010-07-01

    Patterns of geographic variation in communication systems can provide insight into the processes that drive phenotypic evolution. Although work in birds, anurans, and insects demonstrates that acoustic signals are sensitive to diverse selective and stochastic forces, processes that shape variation in mammalian vocalizations are poorly understood. We quantified geographic variation in the advertisement songs of sister species of singing mice, montane rodents with a unique mode of vocal communication. We tested three hypotheses to explain spatial variation in the song of the lower altitude species, Scotinomys teguina: selection for species recognition in sympatry with congener, S. xerampelinus, acoustic adaptation to different environments, and stochastic divergence. Mice were sampled at seven sites in Costa Rica and Panamá; genetic distances were estimated from mitochondrial control region sequences, between-site differences in acoustic environment were estimated from climatic data. Acoustic, genetic and geographic distances were all highly correlated in S. teguina, suggesting that population differentiation in song is largely shaped by genetic drift. Contrasts between interspecific genetic-acoustic distances were significantly greater than expectations derived from intraspecific contrasts, indicating accelerated evolution of species-specific song. We propose that, although much intraspecific acoustic variation is effectively neutral, selection has been important in shaping species differences in song. PMID:20148958

  19. Analysis of Coupled Multiphase Fluid Flow, Heat Transfer and Mechanical Deformation at the Yucca Mountain Drift Scale Test

    SciTech Connect

    J. Rutqvist; C.F. Tsang; Y. Tsang

    2005-05-17

    A numerical simulation of coupled multiphase fluid flow, heat transfer, and mechanical deformation was carried out to study coupled thermal-hydrological-mechanical (THM) processes at the Yucca Mountain Drift Scale Test (DST) and for validation of a coupled THM numerical simulator. The ability of the numerical simulator to model relevant coupled THM processes at the DST was evaluated by comparison of numerical results to in situ measurements of temperature, water saturation, displacement, and fracture permeability. Of particular relevance for coupled THM processes are thermally induced rock-mass stress and deformations, with associated changes in fracture aperture and fractured rock permeability. Thermally induced rock-mass deformation and accompanying changes in fracture permeability were reasonably well predicted using a continuum elastic model, although some individual measurements of displacement and permeability indicate inelastic mechanical responses. It is concluded that fracture closure/opening caused by a change in thermally induced normal stress across fractures is an important mechanism for changes in intrinsic fracture permeability at the DST, whereas fracture shear dilation appears to be less significant. Observed and predicted maximum permeability changes at the DST are within one order of magnitude. These data are important for bounding model predictions of potential changes in rock-mass permeability at a future repository in Yucca Mountain.

  20. Coupled Analysis of Change in Fracture Permeability during the Cooling Phase of the Yucca Mountain Drift Scale Test

    SciTech Connect

    Rutqvist, Jonny; Rutqvist, J.; Freifeld, B.; Tsang, Y.W.; Min, K.B.; Elsworth, D.

    2008-06-01

    This paper presents results from a coupled thermal, hydrological and mechanical analysis of thermally-induced permeability changes during heating and cooling of fractured volcanic rock at the Drift Scale Test at Yucca Mountain, Nevada. The analysis extends the previous analysis of the four-year heating phase to include newly available data from the subsequent four year cooling phase. The new analysis of the cooling phase shows that the measured changes in fracture permeability follows that of a thermo-hydro-elastic model on average, but at several locations the measured permeability indicates (inelastic) irreversible behavior. At the end of the cooling phase, the air-permeability had decreased at some locations (to as low as 0.2 of initial), whereas it had increased at other locations (to as high as 1.8 of initial). Our analysis shows that such irreversible changes in fracture permeability are consistent with either inelastic fracture shear dilation (where permeability increased) or inelastic fracture surface asperity shortening (where permeability decreased). These data are important for bounding model predictions of potential thermally-induced changes in rock-mass permeability at a future repository at Yucca Mountain.

  1. Microgravity access as a means for testing therapeutic pharmaceutics

    NASA Astrophysics Data System (ADS)

    Zimmerman, Robert J.; Simske, Steven J.

    1995-01-01

    Spaceflight results in a unique combination of physiological effects. Immune, musculoskeletal, cardiovascular, renal and other physiological systems are deleteriously affected by the microgravity environment. Many of these effects are analogous to diseases that afflict people on earth; for instance, immunosuppressive disorders and osteoporosis. Chiron Corporation (Emeryville, CA) is interested in using spaceflight as a testing ground for its unique therapeutic pharmaceutics. On STS-60 (Feb. 1994), Chiron, heading up a consortium managed by its CCDS (Center for the Commercial Development of Space) partner Bioserve Space Technologies, investigated the effects of its recombinant interleukin-2 (IL-2) pharmaceutic on preventing the immune system suppression induced that mimicked spaceflight (tail suspension). The recombinant, pegulated IL-2 largely prevented the deleterious effects of spaceflight and particularly suspension on the development of macrophages and the spleen. Based on these findings, Chiron hopes to expand its original market for Il-2 to include veterinary applications. In future missions, Chiron hopes to further explore the physiological effects of IL-2 in preventing the spaceflight effects (STS-63), and to use spaceflight access as a means for testing drugs which may be useful for the treatment of other diseases (e.g., M-CSF for osteoporosis). Spaceflight access has provided Chiron with new applications and new approaches for determining the effects of their pharmaceutics.

  2. Accessibility

    MedlinePlus

    ... www.nlm.nih.gov/medlineplus/accessibility.html MedlinePlus Accessibility To use the sharing features on this page, ... Subscribe to RSS Follow us Disclaimers Copyright Privacy Accessibility Quality Guidelines Viewers & Players MedlinePlus Connect for EHRs ...

  3. Estimation of host rock thermal conductivities using thetemperature data from the drift-scale test at Yucca Mountain,Nevada

    SciTech Connect

    Mukhopadhyay, Sumitra; Tsang, Y.W.

    2003-11-25

    A large volume of temperature data has been collected from a very large, underground heater test, the Drift Scale Test (DST) at Yucca Mountain, Nevada. The DST was designed to obtain thermal, hydrological, mechanical, and chemical (THMC) data in the unsaturated fractured rock of Yucca Mountain. Sophisticated numerical models have been developed to analyze the collected THMC data. In these analyses, thermal conductivities measured from core samples have been used as input parameters to the model. However, it was not known whether these core measurements represented the true field-scale thermal conductivity of the host rock. Realizing these difficulties, elaborate, computationally intensive geostatistical simulations have also been performed to obtain field-scale thermal conductivity of the host rock from the core measurements. In this paper, we use the temperature data from the DST as the input (instead of the measured core-scale thermal conductivity values) to develop an estimate of the field-scale thermal conductivity values. Assuming a conductive thermal regime, we develop an analytical solution for the temperature rise in the host rock of the DST; and using a nonlinear fitting routine, we obtain a best-fit estimate of field-scale thermal conductivity for the DST host rock. The temperature data collected from the DST shows clear evidence of two distinct thermal regimes: a zone below boiling (wet) and a zone above boiling (dry). We obtain estimates of thermal conductivity for both the wet and dry zones. We also analyze the sensitivity of these estimates to the input heating power of the DST.

  4. Development and testing of a laboratory spray table methodology to bioassay simulated levels of aerial spray drift

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this work was to develop a repeatable methodology for bioassaying simulated levels of aerially applied glyphosate at deposition levels ranging from 1/3 to 1/100 of labeled rate at droplet sizes of 100 µm in a spray table environment. These drift deposition levels are consistent wit...

  5. Approaches to modeling coupled thermal, hydrological, and chemicalprocesses in the Drift Scale Heater Test at Yucca Mountain.

    SciTech Connect

    Sonnenthal, E.; Ito, K.; Spycher, N.; Yui, M.; Apps, J.; Sugita,Y.; Conrad, M.; Kawakami, S.

    2005-03-01

    A large-scale underground thermal test (Drift Scale Test DST) in fractured volcanic tuff resulted in changes to water and gas chemistry as well as mineral precipitation and dissolution in fractures. Thermal, hydrological, and chemical (THC) processes in the DST were modeled by Lawrence Berkeley National Laboratory ''LBNL'' and Japan Nuclear Cycle Development Institute ''JNC'' as part of the international working group DECOVALEX. Predictions of THC processes in the DST for the 4-year heating and 4-year cooling periods were initially performed by the LBNL group, with the current model reflecting a revised heater operation history and model. JNC used primarily the original data from the prediction and created a new model to evaluate a selected set of data. The approaches taken by the groups differed in several ways and a comparison of the methodologies and results of the simulations allow for a better understanding of modeling coupled processes in unsaturated fractured rock. The LBNL model represented the fractures and rock matrix as a fully interacting dual-continuum (in terms of fluid, heat, and chemical transport) with the local mineral water gas reactions treated by kinetic and equilibrium reactions. The JNC model represented the fractures and matrix as a single effective continuum, with equilibrium mineral-water reactions controlling the chemical evolution. Both models considered aqueous species transport, with gas phase CO2 transport only considered in the LBNL model. Comparisons to data collected from the DST illustrate the behavior of the models and their ability to capture the relevant THC processes. Overall, both models capture the temperature evolution in the rock quite closely, although the JNC model gave a closer match to the initial temperature rise in the rock, likely owing to the use of site-specific thermal data as opposed to average properties used for the LBNL model. Both models showed the contrasting solubility effects of increasing temperature on

  6. 10 CFR 26.65 - Pre-access drug and alcohol testing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Pre-access drug and alcohol testing. 26.65 Section 26.65 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.65 Pre-access drug and alcohol testing. (a) Purpose. This section contains pre-access...

  7. 10 CFR 26.65 - Pre-access drug and alcohol testing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Pre-access drug and alcohol testing. 26.65 Section 26.65 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.65 Pre-access drug and alcohol testing. (a) Purpose. This section contains pre-access...

  8. 10 CFR 26.65 - Pre-access drug and alcohol testing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Pre-access drug and alcohol testing. 26.65 Section 26.65 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.65 Pre-access drug and alcohol testing. (a) Purpose. This section contains pre-access...

  9. 10 CFR 26.65 - Pre-access drug and alcohol testing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Pre-access drug and alcohol testing. 26.65 Section 26.65 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.65 Pre-access drug and alcohol testing. (a) Purpose. This section contains pre-access...

  10. Extremely small test cell structure for resistive random access memory element with removable bottom electrode

    SciTech Connect

    Koh, Sang-Gyu; Kishida, Satoru; Kinoshita, Kentaro

    2014-02-24

    We established a method of preparing an extremely small memory cell by fabricating a resistive random access memory (ReRAM) structure on the tip of a cantilever of an atomic force microscope. This structure has the high robustness against the drift of the cantilever, and the effective cell size was estimated to be less than 10 nm in diameter due to the electric field concentration at the tip of the cantilever, which was confirmed using electric field simulation. The proposed structure, which has a removable bottom electrode, enables not only the preparation of a tiny ReRAM structure but also the performance of unique experiments, by making the most of its high robustness against the drift of the cantilever.

  11. Direct access testing in the clinical laboratory: should laboratories offer testing services directly to the consumer?

    PubMed

    Halsey, J F

    2000-01-01

    This article outlines the author's views on the many issues to consider if a laboratory plans to initiate a program to offer clinical laboratory testing directly to the public. Direct access testing and why is it important are discussed in detail. The regulatory issues are outlined with some alternatives for laboratories in states with restrictive regulations. To illustrate many of the operational issues to consider, the author describes the Personal Diagnostic Center (PDC) in Kansas City. Finally, some of the key business issues are mentioned, including several approaches to promote this type of testing program. PMID:11210210

  12. Geographic Variation in the Acoustic Traits of Greater Horseshoe Bats: Testing the Importance of Drift and Ecological Selection in Evolutionary Processes

    PubMed Central

    Sun, Keping; Luo, Li; Kimball, Rebecca T.; Wei, Xuewen; Jin, Longru; Jiang, Tinglei; Li, Guohong; Feng, Jiang

    2013-01-01

    Patterns of intraspecific geographic variation of signaling systems provide insight into the microevolutionary processes driving phenotypic divergence. The acoustic calls of bats are sensitive to diverse evolutionary forces, but processes that shape call variation are largely unexplored. In China, Rhinolophus ferrumequinum displays a diverse call frequency and inhabits a heterogeneous landscape, presenting an excellent opportunity for this kind of research. We quantified geographic variation in resting frequency (RF) of echolocation calls, estimated genetic structure and phylogeny of R. ferrumequinum populations, and combined this with climatic factors to test three hypotheses to explain acoustic variation: genetic drift, cultural drift, and local adaptation. Our results demonstrated significant regional divergence in frequency and phylogeny among the bat populations in China's northeast (NE), central-east (CE) and southwest (SW) regions. The CE region had higher frequencies than the NE and SW regions. Drivers of RF divergence were estimated in the entire range and just the CE/NE region (since these two regions form a clade). In both cases, RF divergence was not correlated with mtDNA or nDNA genetic distance, but was significantly correlated with geographic distance and mean annual temperature, indicating cultural drift and ecological selection pressures are likely important in shaping RF divergence among different regions in China. PMID:23950926

  13. 49 CFR 219.206 - FRA access to breath test results.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false FRA access to breath test results. 219.206 Section 219.206 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 219.206 FRA access to breath test results. Documentation of breath test results must be made...

  14. 49 CFR 219.206 - FRA access to breath test results.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false FRA access to breath test results. 219.206 Section 219.206 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 219.206 FRA access to breath test results. Documentation of breath test results must be made...

  15. 49 CFR 219.206 - FRA access to breath test results.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false FRA access to breath test results. 219.206 Section 219.206 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 219.206 FRA access to breath test results. Documentation of breath test results must be made...

  16. 49 CFR 219.206 - FRA access to breath test results.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false FRA access to breath test results. 219.206 Section 219.206 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 219.206 FRA access to breath test results. Documentation of breath test results must be made...

  17. 49 CFR 219.206 - FRA access to breath test results.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false FRA access to breath test results. 219.206 Section 219.206 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 219.206 FRA access to breath test results. Documentation of breath test results must be made...

  18. Drift reduction with drift control adjuvants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous drift reduction adjuvants and spray deposition aids are available to applicators of crop production and protection chemicals. Performance of many of the newly introduced drift control adjuvants has not been well documented for aerial application. Five new drift control adjuvants were sele...

  19. Drift reduction with drift control adjuvants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous drift reduction adjuvants and spray deposition aids are available to applicators of crop production and protection chemicals. Performance of many of the newly introduced drift control adjuvants has not been well documented for aerial application. Four new drift control adjuvants were sele...

  20. An Everting Ureteral Access Sheath: Concepts and In Vitro Testing

    NASA Astrophysics Data System (ADS)

    Lee, Keith L.; Stoller, Marshall L.

    2007-04-01

    Ureteral access sheaths have been a recent innovation in facilitating ureteral stone surgery. Once properly placed, access sheaths allow the movement of ureteroscopes and other instruments through the ureter with minimal injury to the urothelium. However, there are shortcomings of the current device designs. Initial sheath placement requires significant force, and shear stress can injure the ureter. In addition, inadvertent advancement of the outer sheath without the inner introducer stylet can tear and avulse the ureter. A novel eversion design incorporating a lubricous film provides marked improvement over current access sheaths. In bench top and animal models, the eversion shealths require less force during advancement, cause less injury to the urothelial tissue, and have a lower potential of introducing extraneous materials (e.g., microbes) into a simulated urinary tract. While, the everting design provides important advantages over traditional non-everting designs, further preclinical and clinical trials are required.

  1. Is the possible fine-structure constant drift also a test of a time-dependent Planck constant?

    NASA Astrophysics Data System (ADS)

    Öztas, A. M.; Smith, M. L.

    2011-12-01

    The recent publication of spatial and distance variation of the fine-structure constant, α, derived from astronomical data of quasar emissions (QE) is exciting. The decreasing value of α over time, derived from data obtained from the Very Large Telescope (VLT) in Chile, encourages the search for other possible running constants. We surmise that emissions from distant supernovae, type Ia (SNe Ia), which are more blue than predictions are best explained by a decreasing Planck constant with increasing lookback time. We present some results from our theoretical work and comparison to the astronomical observations and suggest that both α and h might be running constants. More data are required to answer several questions about the origin of the "drifting" α and the possible time dependence of h. Astronomical tools such as SNe and QE may be the best means to secure the exacting data needed to confirm or deny these hypotheses.

  2. An experimental test and models of drift and dispersal processes of pallid sturgeon (Scaphirhynchus albus) free embryos in the Missouri River

    USGS Publications Warehouse

    Braaten, P.J.; Fuller, D.B.; Lott, R.D.; Ruggles, M.P.; Brandt, T.F.; Legare, R.G.; Holm, R.J.

    2012-01-01

    Free embryos of wild pallid sturgeon Scaphirhynchus albus were released in the Missouri River and captured at downstream sites through a 180-km reach of the river to examine ontogenetic drift and dispersal processes. Free embryos drifted primarily in the fastest portion of the river channel, and initial drift velocities for all age groups (mean = 0.66–0.70 m s−1) were only slightly slower than mean water column velocity (0.72 m s−1). During the multi-day long-distance drift period, drift velocities of all age groups declined an average of 9.7% day−1. Younger free embryos remained in the drift upon termination of the study; whereas, older age groups transitioned from drifting to settling during the study. Models based on growth of free embryos, drift behavior, size-related variations in drift rates, and channel hydraulic characteristics were developed to estimate cumulative distance drifted during ontogenetic development through a range of simulated water temperatures and velocity conditions. Those models indicated that the average free embryo would be expected to drift several hundred km during ontogenetic development. Empirical data and model results highlight the long-duration, long-distance drift and dispersal processes for pallid sturgeon early life stages. In addition, results provide a likely mechanism for lack of pallid sturgeon recruitment in fragmented river reaches where dams and reservoirs reduce the length of free-flowing river available for pallid sturgeon free embryos during ontogenetic development.

  3. Gender and access to HIV testing and antiretroviral treatments in Thailand: why do women have more and earlier access?

    PubMed

    Le Coeur, Sophie; Collins, Intira J; Pannetier, Julie; Lelièvre, Eva

    2009-09-01

    In the recent scale-up of antiretroviral treatment, gender differences in access to treatment have been reported. In Thailand, as the HIV epidemic became more generalised, there has been a shift from men being disproportionately affected to increased vulnerability of women. In 2007, the Living with Antiretrovirals (LIWA-ANRS 12141) study investigated the gender distribution of all adult patients receiving antiretroviral therapy (N=513 patients) in four community hospitals in northern Thailand and factors influencing the disparities observed. From this retrospective life-event history survey, we found that proportionately more women (53%) were receiving antiretroviral therapy than men, an unexpected result for a country with a higher proportion of infections among men. They were more likely to initiate treatment within one year of diagnosis and were at a more advanced stage of the disease compared to women. This gender distribution is partly explained by the evolving dynamics of the HIV epidemic, initial prioritization of mothers for treatment and earlier access to HIV testing for women. These issues are also entangled with gender differences in the reasons and timing to HIV testing at the individual level. This study found that the majority of men underwent HIV testing for health reasons while the majority of women were tested following family events such as a spouse/child death or during pregnancy. Further qualitative research on gender specific barriers to HIV testing and care, such as perceived low risk of infection, poor access to medical care, lack of social support, actual or anticipated HIV/AIDS-related stigma would provide greater insight. In the meantime, urgent efforts are needed to increase access to voluntary counselling and testing inside and outside the family setting with targeted interventions for men. PMID:19573965

  4. Gauge cooling for the singular-drift problem in the complex Langevin method — a test in Random Matrix Theory for finite density QCD

    NASA Astrophysics Data System (ADS)

    Nagata, Keitaro; Nishimura, Jun; Shimasaki, Shinji

    2016-07-01

    Recently, the complex Langevin method has been applied successfully to finite density QCD either in the deconfinement phase or in the heavy dense limit with the aid of a new technique called the gauge cooling. In the confinement phase with light quarks, however, convergence to wrong limits occurs due to the singularity in the drift term caused by small eigenvalues of the Dirac operator including the mass term. We propose that this singular-drift problem should also be overcome by the gauge cooling with different criteria for choosing the complexified gauge transformation. The idea is tested in chiral Random Matrix Theory for finite density QCD, where exact results are reproduced at zero temperature with light quarks. It is shown that the gauge cooling indeed changes drastically the eigenvalue distribution of the Dirac operator measured during the Langevin process. Despite its non-holomorphic nature, this eigenvalue distribution has a universal diverging behavior at the origin in the chiral limit due to a generalized Banks-Casher relation as we confirm explicitly.

  5. GIT (Glucose Infusion Test): polycentric evaluation of a new test for vascular access recirculation.

    PubMed

    Alloatti, S; Magnasco, A; Bonfant, G; Bonello, F; Ciciani, A M; Fidelio, T; Filiberti, O; Forneris, G; Martina, G; Robaudo, C; Romano, U; Schelotto, C

    2000-01-01

    Introduction. Vascular access recirculation (AR), which is often unacknowledged, remains an important cause of inadequate dialytic dose. The glucose infusion test (GIT) is a new method for detecting and quantifying AR. This paper reports on a polycentric evaluation of the new test and a comparison with the classical Urea-test (UT). Methods. GIT protocol comprises withdrawal from the arterial port (sample A), injection into the venous drip chamber of 1 g glucose in 4 seconds, withdrawal from the arterial port (sample B) continuously from 13 to 17 seconds. Glucose is determined on A and B by a reflectance photometer. If B = A then there is no recirculation. If B exceeds A by at least 20 mg/dl there is recirculation. AR quantification: AR% = (B-A) / 20. GIT was performed on 623 patients from eleven dialysis centers to screen the patients for AR. Subsequently, GIT and Urea-test (UT) were compared in 189 paired tests. The reproducibility of GIT and UT was studied in 28 paired tests performed in sequence. Results. The screening test by GIT was positive in 68 cases (11 %). The majority of positivities was found in central venous catheters (CVC, 27/50 cases, 54 %), whereas only 7 % of artero-venous fistulas (AVF) were positive. In the CVC group, Tesio catheters were more frequently positive compared to Dual Lumen Catheters (64 % vs. 29 %). The comparison GIT - UT showed that results matched in 162 tests (79 negative and 83 positive both by GIT and UT), showing that on the grounds of UT, GIT has high sensitivity and specificity. In 27 tests GIT was positive, but UT negative. This disagreement is due to the different minimal limit of detection, 1 % for GIT and 5% for UT. The reproducibility was greater with GIT than with UT with a lower D% (respectively -0.6 +/- 2.5 and -0.4 +/- 6.1 %, p<0.001) and a lower coefficient of variation (17 vs 33 %). Conclusions. The screening of 623 patients by GIT confirmed that AR in AVF is normally absent, whereas an un-expectedly high

  6. Observational test of shock drift and Fermi acceleration on a seed particle population upstream of earth's bow shock

    NASA Technical Reports Server (NTRS)

    Anagnostopoulos, G. C.; Sarris, E. T.; Krimigis, S. M.

    1988-01-01

    The efficiency of proposed shock acceleration mechanisms as they operate at the bow shock in the presence of a seed energetic particle population was examined using data from simultaneous observations of energetic solar-origin protons, carried out by the IMP 7 and 8 spacecraft in the vicinity of the quasi-parallel (dawn) and quasi-perpendicular (dusk) regions of the earth's bow shock, respectively. The results of observations (which include acceleration effects in the intensities of the energetic protons with energies as high as 4 MeV observed at the vicinity of the dusk bow shock, but no evidence for any particle acceleration at the energy equal to or above 50 keV at the dawn side of the bow shock) indicate that the acceleration of a seed particle population occurs only at the quasi-perpendicular bow shock through shock drift acceleration and that the major source of observed upstream ion populations is the leakage of magnetospheric ions of energies not less than 50 keV, rather than in situ acceleration.

  7. From Seismic Characterization to Coupled Process Testing Along Drifts at LSBB as an Example of Establishing an International Facility for a Worldwide Network of Underground Research Laboratories

    NASA Astrophysics Data System (ADS)

    Gaffet, S.; Wang, J. S.

    2009-12-01

    The Laboratoire Souterrain à Bas Bruit (LSBB) at Rustrel France is a French National Instrumented Infrastructure, CNRS, dedicated to inter-Disciplinary Underground Science and Technology. The underground galleries and the surrounding carbonate rock formations are well characterized by seismic imaging studies obtained with sensors both along the ridges and underground along the drifts. The facility is horizontally accessible with the main tunnel following an L-shape. The deepest is 518m below the surface. The main tunnel continues with a long gallery below the ridge, and ends with an escape shaft to the surface. Electrical and fiber optic communication cables connect the galleries and the underground to the huts on the surface. All data from LSBB are distributed on line (http://lsbb.oca.eu) and data from the 3D broadband seismic array are fed in real time (delay of ~4s) to the European Union seismic network (see streams RUSF_01, 03, 04, 05, 06, and 07 at http://www.orfeus-eu.org/Data-info/orbstats.html). Concurrently with establishing the seismic network, the LSBB characterizes its low noise environment, including its low ambient magnetic noise with a (SQUID)2 magnetometer, located 518m below the surface in a shielded cage. The magnetic noise floor in the cage is lower than 2fT/SQRT(Hz). Together with the seismic network and the magnetic sensor, tiltmeters, radiation sensors, groundwater pressure and chemistry monitoring devices are installed to characterize the unsaturated environment along the tunnel. Seasonal seepage observations are also collected. 3 national research projects are currently carried out along dedicated tunnels: (1) the project on High-Pulse Poroelasticity Protocol (HPPP) for geophysical monitoring of CO2 injection in reservoirs (http://hppp.unice.fr/), focusing currently on hydromechanical testing in carbonate rock; (2) the MAXWELL electromagnetic project on broadband imaging which employs joint resistivity and permittivity inversion (http

  8. Flow-test device fits into restricted access passages

    NASA Technical Reports Server (NTRS)

    Fitzgerald, J. J.; Oberschmidt, M.; Rosenbaum, B. J.

    1967-01-01

    Test device using a mandrel with a collapsible linkage assembly enables a fluid flow sensor to be properly positioned in a restricted passage by external manipulation. This device is applicable to the combustion chamber of a rocket motor.

  9. A Double Take at 'Serpent' Drift

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit took this microscopic imager picture of the drift dubbed 'Serpent' on Spirit's 73rd martian day on Mars after successfully digging into the side of the drift. The image, which has a black box at the top caused by missing data, captures a transition part of the drift where lighter, undisturbed material meets disturbed, darker material. The microscopic view of the undisturbed material reveals sphere-like grains with diameters between one and two millimeters (.04 and .08 inches), which are similar to the grains Spirit observed in other drift areas near Spirit's landing site, Gusev Crater. These larger grains form a single layer or crust on the surface of the drift and are covered in a fine layer of martian dust.

    Most interesting to scientists are the fine grains making up the interior of Serpent drift. The grains of sand found within drifts or dunes on Earth are usually about 200 micrometers (.008 inches) in diameter--much like sand on a beach. On Earth, dunes are formed when sand particles of this size are bounced across a surface by wind and collect together as drifts. Smaller particles, like the ones making up Serpent drift, would not necessarily collect into a dune on Earth, but would more likely be distributed across the surface like dust. The fine grains making up the interior of Serpent drift are no larger than 50 or 60 micrometers (.002 inches) and can be compared to silt on Earth.

    How did this very fine material managed to accumulate into a drift? Earth-based tests that simulate the wind speed and atmospheric density of Mars have found it difficult to reproduce dunes with grain particles as small as those found in the Serpent drift. However, Earth-based tests cannot duplicate the gravity of Mars, which is one-third that of the gravity on Earth. This environmental factor is a likely contributor to the diminutive material making up Serpent drift.

  10. A Double Take at 'Serpent' Drift

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit took this microscopic imager picture of the drift dubbed 'Serpent' on Spirit's 73rd martian day on Mars after successfully digging into the side of the drift. The image is the first-ever microscopic look inside a drift. It captures only the scuffed interior of the Serpent drift and is dominated by larger pea-shaped particles. These grains are not natural to the inside of the drift, but are crust particles that have tumbled into the scuffed area as a result of the digging. These grains lost their dust cover in the process of falling into the scuff, giving scientists clues about the strength -- or lack of strength -- of the bond between the dust and sand particles.

    Most interesting to scientists are the fine grains making up the interior of Serpent drift. The grains of sand found within drifts or dunes on Earth are usually about 200 micrometers (.008 inches) in diameter -- much like sand on a beach. On Earth, dunes are formed when sand particles of this size are bounced across a surface by wind and collect together as drifts. Smaller particles, like the ones making up Serpent drift, would not necessarily collect into a dune on Earth, but would more likely be distributed across the surface like dust. The fine grains making up the interior of Serpent drift are no larger than 50 or 60 micrometers (.002 inches) and can be compared to silt on Earth.

    How did this very fine material manage to accumulate into a drift? Earth-based tests that simulate the wind speed and atmospheric density of Mars have found it difficult to reproduce dunes with grain particles as small as those found in the Serpent drift. However, Earth-based tests cannot duplicate the gravity of Mars, which is one-third that of the gravity on Earth. This environmental factor is a likely contributor to the diminutive material making up Serpent drift.

  11. Notes on drift theory

    NASA Technical Reports Server (NTRS)

    Burger, R. A.; Moraal, H.; Webb, G. M.

    1985-01-01

    It is shown that there is a simpler way to derive the average guiding center drift of a distribution of particles than via the so-called single particle analysis. Based on this derivation it is shown that the entire drift formalism can be considerably simplified, and that results for low order anisotropies are more generally valid than is usually appreciated. This drift analysis leads to a natural alternative derivation of the drift velocity along a neutral sheet.

  12. Using Technology to Create and Administer Accessible Tests

    ERIC Educational Resources Information Center

    Salend, Spencer

    2009-01-01

    Technology is transforming many aspects of society including the ways teachers teach and students learn. Although technology has been firmly established as a teaching tool across a range of content areas, educators are realizing that technology also offers innovative ways to help their students take standardized tests that comply with the mandates…

  13. Variation in Direct Access to Tests to Investigate Cancer: A Survey of English General Practitioners

    PubMed Central

    Nicholson, Brian D.; Oke, Jason L.; Rose, Peter W.; Mant, David

    2016-01-01

    Background The 2015 NICE guidelines for suspected cancer recommend that English General Practitioners have direct access to diagnostic tests to investigate symptoms of cancer that do not meet the criteria for urgent referral. We aimed to identify the proportion of GPs in England with direct access to these tests. Methods We recruited 533 English GPs through a national clinical research network to complete an online survey about direct access to laboratory, radiology, and endoscopy tests in the three months leading up to the release of the 2015 NICE guidance. If they had direct access to a diagnostic test, GPs were asked about the time necessary to arrange a test and receive a report. Results are reported by NHS sub-region and, adjusting for sampling, for England as a whole. Results Almost all GPs reported direct access to x-ray and laboratory investigations except faecal occult blood testing (54%, 95% CI 49–59%) and urine protein electrophoresis (89%, 95% CI 84–92%). Fewer GPs had direct access to CT scans (54%, 95% CI 49–59%) or endoscopy (colonoscopy 32%, 95% CI 28–37%; gastroscopy 72%, 95% CI 67–77%). There was significant variation in direct access between NHS regions for the majority of imaging tests—for example, from 20 to 85% to MRI. Apart from x-ray, very few GPs (1–22%) could access radiology and endoscopy within the timescales recommended by NICE. The modal request to test time was 2–4 weeks for routine radiology and 4–6 weeks for routine endoscopy with results taking another 1–2 weeks. Conclusion At the time that the 2015 NICE guideline was released, local investment was required to not only provide direct access but also reduce the interval between request and test and speed up reporting. Further research using our data as a benchmark is now required to identify whether local improvements in direct access have been achieved in response to the NICE targets. If alternative approaches to test access are to be proposed they must be

  14. Inoculation against forgetting: advantages of immediate versus delayed initial testing due to superior verbatim accessibility.

    PubMed

    Pansky, Ainat

    2012-11-01

    In this study, potential benefits of early memory testing were examined in terms of "inoculating" eyewitness memory against forgetting. As predicted by fuzzy trace theory (e.g., Reyna & Titcomb, 1997), a larger testing advantage in the delayed recall of event details was expected after immediate testing than after delayed testing because of the decline in accessibility of verbatim traces over time. However, memory for only the gist of these details was expected to be relatively stable over time, resulting in a smaller (if any) effect of the timing of interpolated testing. After viewing a target event, participants were questioned about event items immediately, after a 24-hr delay, or after a 48-hr delay and were free to respond at either the gist or the verbatim level. Verbatim memory for event details was tested 72 hr after the event. As expected, immediate interpolated testing improved verbatim memory performance on the final test more than delayed testing did, yielding a larger testing effect. Furthermore, the effect of the timing of interpolated testing on the magnitude of the testing effect was mediated by verbatim accessibility at interpolated testing. In contrast, memory for only the gist of event details was unaffected by the timing of interpolated testing, both on the interpolated test and on the final test. The findings highlight the role of declining verbatim memory over time in accounting for the advantage of immediate over delayed interpolated testing in inoculating eyewitness memory against forgetting of detailed information. PMID:22582965

  15. Examining the Accessibility of a Computerized Adapted Test Using Assistive Technology

    ERIC Educational Resources Information Center

    Kamei-Hannan, Cheryl

    2008-01-01

    This study examined the accessibility barriers of a computerized adapted test called the Measure of Academic Performance. The results showed that as magnification increased, time on the test increased and students required visual efficiency skills. Students who used refreshable braille displays were faced with several obstacles. (Contains 4…

  16. 46 CFR 4.06-15 - Accessibility of chemical testing devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... sufficient number of urine-specimen collection and shipping kits meeting the requirements of 49 CFR part 40... 46 Shipping 1 2012-10-01 2012-10-01 false Accessibility of chemical testing devices. 4.06-15... MARINE CASUALTIES AND INVESTIGATIONS Mandatory Chemical Testing Following Serious Marine...

  17. 46 CFR 4.06-15 - Accessibility of chemical testing devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... sufficient number of urine-specimen collection and shipping kits meeting the requirements of 49 CFR part 40... 46 Shipping 1 2011-10-01 2011-10-01 false Accessibility of chemical testing devices. 4.06-15... MARINE CASUALTIES AND INVESTIGATIONS Mandatory Chemical Testing Following Serious Marine...

  18. 46 CFR 4.06-15 - Accessibility of chemical testing devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... sufficient number of urine-specimen collection and shipping kits meeting the requirements of 49 CFR part 40... 46 Shipping 1 2014-10-01 2014-10-01 false Accessibility of chemical testing devices. 4.06-15... MARINE CASUALTIES AND INVESTIGATIONS Mandatory Chemical Testing Following Serious Marine...

  19. 46 CFR 4.06-15 - Accessibility of chemical testing devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... sufficient number of urine-specimen collection and shipping kits meeting the requirements of 49 CFR part 40... 46 Shipping 1 2013-10-01 2013-10-01 false Accessibility of chemical testing devices. 4.06-15... MARINE CASUALTIES AND INVESTIGATIONS Mandatory Chemical Testing Following Serious Marine...

  20. 46 CFR 4.06-15 - Accessibility of chemical testing devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... sufficient number of urine-specimen collection and shipping kits meeting the requirements of 49 CFR part 40... 46 Shipping 1 2010-10-01 2010-10-01 false Accessibility of chemical testing devices. 4.06-15... MARINE CASUALTIES AND INVESTIGATIONS Mandatory Chemical Testing Following Serious Marine...

  1. Dike/Drift Interactions

    SciTech Connect

    E. Gaffiney

    2004-11-23

    This report presents and documents the model components and analyses that represent potential processes associated with propagation of a magma-filled crack (dike) migrating upward toward the surface, intersection of the dike with repository drifts, flow of magma in the drifts, and post-magma emplacement effects on repository performance. The processes that describe upward migration of a dike and magma flow down the drift are referred to as the dike intrusion submodel. The post-magma emplacement processes are referred to as the post-intrusion submodel. Collectively, these submodels are referred to as a conceptual model for dike/drift interaction. The model components and analyses of the dike/drift interaction conceptual model provide the technical basis for assessing the potential impacts of an igneous intrusion on repository performance, including those features, events, and processes (FEPs) related to dike/drift interaction (Section 6.1).

  2. Free Drifting Buoys

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Information was exchanged between people directly involved with the development, use, and/or potential use of free drifting buoys. Tracking systems and techniques, where methods and accuracy of optical, radio, radar, satellite, and sonic tracking of free-drifting buoys were discussed. Deployment and retrieval covering methods currently used or planned in the deployment and retrieval of free-drifting buoys from boats, ships, helicopters, fixed platforms, and fixed-wing aircraft were reported. Simulation, sensors, and data emphasizing the status of water circulation modeling, and sensors useful on free-drifting buoys, and data display and analysis were described.

  3. Field investigation of the drift shadow

    SciTech Connect

    Su, Grace W.; Kneafsey, Timothy J.; Ghezzehei, Teamrat A.; Marshall, Brian D.; Cook, Paul J.

    2005-09-08

    A drift shadow is an area immediately beneath an undergroundvoidthat, in theory, will be relatively drier than the surrounding rockmass. Numerical and analytical models of water flow through unsaturatedrock predict the existence of a drift shadow, but field tests confirmingits existence have yet to be performed. Proving the existence of driftshadows and understanding their hydrologic and transport characteristicscould provide a better understanding of how contaminants move in thesubsurface if released from waste emplacement drifts such as the proposednuclear waste repository at Yucca Mountain, Nevada. We describe the fieldprogram that will be used to investigate the existence of a drift shadowand the corresponding hydrological process at the Hazel-Atlas silica-sandmine located at the Black Diamond Mines Regional Preserve in Antioch,California. The location and configuration of this mine makes it anexcellent site to observe and measure drift shadow characteristics. Themine is located in a porous sandstone unit of the Domengine Formation, anapproximately 230 meter thick series of interbedded Eocene-age shales,coals, and massive-bedded sandstones. The mining method used at the minerequired the development of two parallel drifts, one above the other,driven along the strike of the mined sandstone stratum. Thisconfiguration provides the opportunity to introduce water into the rockmass in the upper drift and to observe and measure its flow around theunderlying drift. The passive and active hydrologic tests to be performedare described. In the passive method, cores will be obtained in a radialpattern around a drift and will be sectioned and analyzed for in-situwater content and chemical constituents. With the active hydrologic test,water will be introduced into the upper drift of the two parallel driftsand the flow of the water will be tracked as it passes near the bottomdrift. Tensiometers, electrical resistance probes, neutron probes, andground penetrating radar may be

  4. HIV risk behavior and access to services: what predicts HIV testing among heterosexually active homeless men?

    PubMed

    Wenzel, Suzanne L; Rhoades, Harmony; Tucker, Joan S; Golinelli, Daniela; Kennedy, David P; Zhou, Annie; Ewing, Brett

    2012-06-01

    HIV is a serious epidemic among homeless persons, where rates of infection are estimated to be three times higher than in the general population. HIV testing is an effective tool for reducing HIV transmission and for combating poor HIV/AIDS health outcomes that disproportionately affect homeless persons, however, little is known about the HIV testing behavior of homeless men. This study examined the association between individual (HIV risk) and structural (service access) factors and past year HIV testing. Participants were a representative sample of 305 heterosexually active homeless men interviewed from meal programs in the Skid Row region of Los Angeles. Logistic regression examined the association between past year HIV testing and demographic characteristics, HIV risk behavior, and access to other services in the Skid Row area in the past 30 days. Despite high rates of past year HIV testing, study participants also reported high rates of HIV risk behavior, suggesting there is still significant unmet need for HIV prevention among homeless men. Having recently used medical/dental services in the Skid Row area (OR: 1.91; CI: 1.09, 3.35), and being a military veteran (OR: 2.10; CI: 1.01-4.37) were significantly associated with HIV testing service utilization. HIV testing was not associated with HIV risk behavior, but rather with access to services and veteran status, the latter of which prior research has linked to increased service access. We suggest that programs encouraging general medical service access may be important for disseminating HIV testing services to this high-risk, vulnerable population. PMID:22676465

  5. FIELD INVESTIGATION OF THE DRIFT SHADOW

    SciTech Connect

    G.W. Su; T.J. Kneafsey

    2006-02-01

    A drift shadow is an area immediately beneath an underground void that, in theory, will be relatively drier than the surrounding rock mass. Numerical and analytical models of water flow through unsaturated rock predict the existence of a drift shadow, but field tests confirming the existence of the drift shadow have yet to be performed. Proving the existence of drift shadows and understanding their hydrologic and transport characteristics could provide a better understanding of how contaminants move in the subsurface if released from waste emplacement drifts such as the proposed nuclear waste repository at Yucca Mountain, Nevada. We describe the field program that will be used to investigate the existence of a drift shadow--and the corresponding hydrological process at the Hazel-Atlas silica-sand mine located at the Black Diamond Mines Regional Preserve in Antioch, California. The location and configuration of this mine makes it an excellent site to observe and measure drift shadow characteristics. The mine is located in a porous sandstone unit of the Domengine formation, an approximately 230 meter thick series of interbedded Eocene-age shales, coals, and massive-bedded sandstones. The mining method used at the mine required the development of two parallel drifts, one above the other, driven along the strike of the mined sandstone stratum. This configuration provides the opportunity to introduce water into the rock mass in the upper drift and to observe and measure its flow around the underlying drift. The passive and active hydrologic tests to be performed are described. In the passive method, cores will be obtained in a radial pattern around a drift and will be sectioned and analyzed for in-situ water content using a gravimetric technique, as well as analyzed for chemistry. With the active hydrologic test, water will be introduced into the upper drift of the two parallel drifts and the flow of the water will be tracked as it passes near the bottom drift

  6. Vapor Transport Through Fractures and Other High-Permeability Paths: Its Role in the Drift Scale Test at Yucca Mountain, Nevada

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, S.; Tsang, Y. W.

    2001-12-01

    Heating unsaturated fractured tuff sets off a series of complicated thermal-hydrological (TH) processes, which result in large-scale redistribution of moisture in the host rock. Moisture redistribution arises from boiling of water near heat sources, transport of vapor away from those heat sources, condensation of that vapor in cooler rock, and subsequent gravity drainage of condensate through fractures. Vapor transport through high-permeability paths, which include both the fractures in the rock and other conduits, contributes to the evolution of these TH processes in two ways. First, the highly permeable natural fractures provide easy passage for vapor away from the heat sources. Second, these fractures and other highly permeable conduits allow vapor (and the associated energy) to escape the rock through open boundaries of the test domain. The overall impact of vapor transport on the evolution of the TH processes can be more easily understood in the context of the Drift Scale Test (DST), the largest ever in situ heater test in unsaturated fractured tuff. The DST, in which a large volume of rock has been heated for four years now, is located in the middle nonlithophysal (Tptpmn) stratigraphic unit of Yucca Mountain, Nevada. The fractured tuff in Tptpmn contains many well-connected fractures. In the DST, heating is provided by nine cannister heaters placed in a five-meter-diameter Heated Drift (HD) and fifty wing heaters installed orthogonal to the axis of the HD. The test has many instrumentation boreholes, some of which are not sealed by packers or grout and may provide passage for vapor and energy. Of these conduits, the boreholes housing the wing heaters are most important for vapor transport because of their proximity to heat sources. While part of the vapor generated by heating moves away from the heat sources through the fractures and condenses elsewhere in the rock, the rest of the vapor, under gas-pressure difference, enters the HD by way of the high

  7. Field investigation of the drift shadow

    USGS Publications Warehouse

    Su, G.W.; Kneafsey, T.J.; Ghezzehei, T.A.; Cook, P.J.; Marshall, B.D.

    2006-01-01

    The "Drift Shadow" is defined as the relatively drier region that forms below subsurface cavities or drifts in unsaturated rock. Its existence has been predicted through analytical and numerical models of unsaturated flow. However, these theoretical predictions have not been demonstrated empirically to date. In this project we plan to test the drift shadow concept through field investigations and compare our observations to simulations. Based on modeling studies we have an identified a suitable site to perform the study at an inactive mine in a sandstone formation. Pretest modeling studies and preliminary characterization of the site are being used to develop the field scale tests.

  8. FIELD INVESTIGATIONS OF THE DRIFT SHADOW

    SciTech Connect

    G. W. Su, T. J. Kneafsey, T. A. Ghezzehei, B. D. Marshall, and P. J. Cook

    2006-01-15

    The ''Drift Shadow'' is defined as the relatively drier region that forms below subsurface cavities or drifts in unsaturated rock. Its existence has been predicted through analytical and numerical models of unsaturated flow. However, these theoretical predictions have not been demonstrated empirically to date. In this project they plan to test the drift shadow concept through field investigations and compare our observations to simulations. Based on modeling studies they have an identified suitable site to perform the study at an inactive mine in a sandstone formation. Pretest modeling studies and preliminary characterization of the site are being used to develop the field scale tests.

  9. Booktalking: Avoiding Summer Drift

    ERIC Educational Resources Information Center

    Whittingham, Jeff; Rickman, Wendy A.

    2015-01-01

    Summer drift, otherwise known as loss of reading comprehension skills or reading achievement, has been a well-known and well-documented phenomenon of public education for decades. Studies from the late twentieth century to the present have demonstrated a slowdown in summer drift attributed to specific summer reading programs addressing motivation…

  10. Abstraction of Drift Seepage

    SciTech Connect

    J.T. Birkholzer

    2004-11-01

    This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package corrosion or radionuclide transport.

  11. What Constrains the Accuracy of Metacomprehension Judgments? Testing the Transfer-Appropriate-Monitoring and Accessibility Hypotheses

    ERIC Educational Resources Information Center

    Dunlosky, J.; Rawson, K.A.; Middleton, E.L.

    2005-01-01

    We evaluated two hypotheses-transfer appropriate monitoring (TAM) and the accessibility hypothesis-that explain why the accuracy of metacomprehension judgments is commonly low. In 2 experiments, participants read six expository texts, made global judgments about how well they would perform on a test over each text, and made term-specific judgments…

  12. Man-computer Inactive Data Access System (McIDAS). [design, development, fabrication, and testing

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A technical description is given of the effort to design, develop, fabricate, and test the two dimensional data processing system, McIDAS. The system has three basic sections: an access and data archive section, a control section, and a display section. Areas reported include hardware, system software, and applications software.

  13. 76 FR 56712 - CLIA Program and HIPAA Privacy Rule; Patients' Access to Test Reports

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-14

    ... December 28, 2000, the Department published a final rule in the Federal Register (65 FR 82462) entitled... was amended on August 14, 2002 (67 FR 53182). The Privacy Rule at 45 CFR 164.524 provides individuals... conflict with the CLIA requirements that limited patient access to test reports (65 FR 82485)....

  14. Design of access-tube TDR sensor for soil water content: Testing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil water measurement is important in water management for irrigation and hydrologic sciences. The purpose of this paper is to develop and test the design of a cylindrical access-tube mounted waveguide for use in time-domain reflectometry (TDR) for in-situ soil water content sensing. Several prot...

  15. The Changing Faces of Corruption in Georgian Higher Education: Access through Times and Tests

    ERIC Educational Resources Information Center

    Orkodashvili, Mariam

    2012-01-01

    This article presents a comparative-historical analysis of access to higher education in Georgia. It describes the workings of corrupt channels during the Soviet and early post-Soviet periods and the role of standardized tests in fighting corruption in higher education admission processes after introduction of the Unified National Entrance…

  16. Analysis of Thermally Induced Changes in Fractured Rock Permeability during Eight Years of Heating and Cooling at the Yucca Mountain Drift Scale Test

    SciTech Connect

    Rutqvist, J.; Freifeld, B.; Min, K.-B.; Elsworth, D.; Tsang, Y.

    2008-06-01

    We analyzed a data set of thermally induced changes in fractured rock permeability during a four-year heating (up to 200 C) and subsequent four-year cooling of a large volume, partially saturated and highly fractured volcanic tuff at the Yucca Mountain Drift Scale Test, in Nevada, USA. Permeability estimates were derived from about 700 pneumatic (air-injection) tests, taken periodically at 44 packed-off borehole intervals during the heating and cooling cycle from November 1997 through November 2005. We analyzed air-permeability data by numerical modeling of thermally induced stress and moisture movements and their impact on air permeability within the highly fractured rock. Our analysis shows that changes in air permeability during the initial four-year heating period, which were limited to about one order of magnitude, were caused by the combined effects of thermal-mechanically-induced stress on fracture aperture and thermal-hydrologically-induced changes in fracture moisture content. At the end of the subsequent four-year cooling period, air-permeability decreases (to as low as 0.2 of initial) and increases (to as high as 1.8 of initial) were observed. By comparison to the calculated thermo-hydro-elastic model results, we identified these remaining increases or decreases in air permeability as irreversible changes in intrinsic fracture permeability, consistent with either inelastic fracture shear dilation (where permeability increased) or inelastic fracture surface asperity shortening (where permeability decreased). In this paper, we discuss the possibility that such fracture asperity shortening and associated decrease in fracture permeability might be enhanced by dissolution of highly stressed surface asperities over years of elevated stress and temperature.

  17. Field Investigation of the Drift Shadow

    NASA Astrophysics Data System (ADS)

    Su, G. W.; Kneafsey, T. J.; Ghezzehei, T. A.; Marshall, B. D.; Cook, P. J.

    2005-12-01

    A drift shadow is an area immediately beneath an underground void that, in theory, will be relatively drier than the surrounding rock mass. Numerical and analytical models of water flow through unsaturated rock predict the existence of a drift shadow, but field tests confirming its existence have yet to be performed. Proving the existence of drift shadows and understanding their hydrologic and transport characteristics could provide a better understanding of how contaminants move in the subsurface if released from waste emplacement drifts such as the proposed nuclear waste repository at Yucca Mountain, Nevada. We describe the field program that will be used to investigate the existence of a drift shadow and the corresponding hydrological process at the Hazel-Atlas silica-sand mine located at the Black Diamond Mines Regional Preserve in Antioch, California. The location and configuration of this mine makes it an excellent site to observe and measure drift shadow characteristics. The mine is located in a porous sandstone unit of the Domengine Formation, an approximately 230 meter thick series of interbedded Eocene-age shales, coals, and massive-bedded sandstones. The mining method used at the mine required the development of two parallel drifts, one above the other, driven along the strike of the mined sandstone stratum. This configuration provides the opportunity to introduce water into the rock mass in the upper drift and to observe and measure its flow around the underlying drift. The passive and active hydrologic tests to be performed are described. In the passive method, cores will be obtained in a radial pattern around a drift and will be sectioned and analyzed for in-situ water content and chemical constituents. With the active hydrologic test, water will be introduced into the upper drift of the two parallel drifts and the flow of the water will be tracked as it passes near the bottom drift. Tensiometers, electrical resistance probes, neutron probes, and

  18. Search Hanford Accessible Reports Electronically system test plan and documentation: Revision 1

    SciTech Connect

    White, E.L.

    1994-12-07

    The purpose of this document is to describe the following items: the approach, resources, and sequence of the testing activities; identifies the components and features to be tested; the personnel responsible for testing; the risks associated with this plan; and test cases and procedures. This document contains all test documentation for the SHARE system. The Search Hanford Accessible Reports Electronically (SHARE) testing process is based upon WHC-CM-3-10, Software Practices, Section SP-3.3 REV 0, and Appendix J REV 0. These procedures and guidelines are based on IEEE Standard 829-1983. The planning in this document was further influenced through guidance in IEEE Standard 1012-1986. This document contains the System, Acceptance, Integration and Component Test Plans, Designs, Procedures, and Cases for SHARE. The Test Cases and procedures have been attached to the document.

  19. Dodging the Drifts

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This image taken by NASA's Mars Exploration Rover Opportunity is a portion of a mosaic acquired by the panoramic camera. The picture highlights the light-toned outcrop on the rim of 'Erebus Crater' and large, dark, wind-deposited drifts that have filled the center of the crater. Opportunity took this image on the rover's 608th sol (Oct. 9, 2005). The rover is driving west, avoiding the large drifts and crossing the low ripples and outcrop to the right. After traversing to the north of the large drift on the horizon (near the center of the image), Opportunity will drive south to the western rim of the crater.

  20. The Electron Drift Instrument for Cluster

    NASA Technical Reports Server (NTRS)

    Paschmann, G.; Melzner, F.; Frenzel, R.; Vaith, H.; Parigger, P.; Pagel, U.; Bauer, O. H.; Haerendel, G.; Baumjohann, W.; Scopke, N.

    1997-01-01

    The Electron Drift Instrument (EDI) measures the drift of a weak beam of test electrons that, when emitted in certain directions, return to the spacecraft after one or more gyrations. This drift is related to the electric field and the gradient in the magnetic field, and these quantities can, by use of different electron energies, be determined separately. As a by-product, the magnetic field strength is also measured. The present paper describes the scientific objectives, the experimental method, and the technical realization of the various elements of the instrument.

  1. HIV testing practices of South African township MSM in the era of expanded access to ART.

    PubMed

    Sandfort, Theo G M; Knox, Justin; Collier, Kate L; Lane, Tim; Reddy, Vasu

    2015-03-01

    While men who have sex with men (MSM) in Africa are at high risk for HIV infection, few of those already infected know their status. Effectively promoting frequent HIV testing-of increasing importance with the expanding accessibility of antiretroviral treatment-requires an understanding of the testing practices in this population. To understand men's HIV testing practices, including their behavior, experiences, and perceptions, we conducted in-depth interviews with 81 black South African MSM (ages 20-39), purposively recruited from four townships. Many men in the sample had tested for HIV. While ever having tested seemed to facilitate repeat testing, men still expressed a high level of discomfort with testing. It was common to test after having engaged in risky behavior, thus increasing anxiety about testing that was already present. Fear that they might test HIV positive caused some men to avoid testing until they were clearly sick, and others to avoid testing completely. HIV testing may increase in this population if it becomes a routine practice, instead of being driven by anxiety-inducing incidents. Mobilization through social support might facilitate frequent testing while education about current treatment options is needed. PMID:25103866

  2. Lithium drifted germanium system

    NASA Technical Reports Server (NTRS)

    Fjarlie, E. J.

    1969-01-01

    General characteristics of the lithium-drifted germanium photodiode-Dewar-preamplifier system and particular operating instructions for the device are given. Information is included on solving operational problems.

  3. HIV testing practices of South African township MSM in the era of expanded access to ART

    PubMed Central

    Sandfort, Theo G. M.; Knox, Justin; Collier, Kate L.; Lane, Tim; Reddy, Vasu

    2014-01-01

    While men who have sex with men (MSM) in Africa are at high risk for HIV infection, few of those already infected know their status. Effectively promoting frequent HIV testing—of increasing importance with the expanding accessibility of antiretroviral treatment—requires an understanding of the testing practices in this population. To understand men’s HIV testing practices, including their behavior, experiences, and perceptions, we conducted in-depth interviews with 81 black South African MSM (ages 20–39), purposively recruited from four townships. Many men in the sample had tested for HIV. While ever having tested seemed to facilitate repeat testing, men still expressed a high level of discomfort with testing. It was common to test after having engaged in risky behavior, thus increasing anxiety about testing that was already present. Fear that they might test HIV positive caused some men to avoid testing until they were clearly sick, and others to avoid testing completely. HIV testing may increase in this population if it becomes a routine practice, instead of being driven by anxiety-inducing incidents. Mobilization through social support might facilitate frequent testing while education about current treatment options is needed. PMID:25103866

  4. A system for model access in tunnels with an unbreathable test medium

    NASA Technical Reports Server (NTRS)

    Howell, R. R.; Joplin, S. D.

    1980-01-01

    In many specialty wind tunnels, test gases other than ambient air are used to meet special testing requirements. A typical example is the use of freon as the test gas to achieve a realistic density ratio between gas and model for exploring flutter stability boundaries. Another example is the use of pressurized air to elevate the stream density and enhance Reynolds number or dynamic pressure simulation. Such specialty tunnels require a system of access o the model which will allow services and changes to the model without exposing personnel to the unnatural and perhaps hostile environment or requiring the venting and purging of the entire tunnel circuit. This paper will describe the plenum and model access systems for the forthcoming U.S. National Transonic facility where gaseous nitrogen (N2) at temperatures between 338 and 78 K and at pressures to 9 bars is used as the test medium. The operation at cold temperatures imposes some additional requirements which make the access systems more difficult to design and time consuming to operate than for conventional wind tunnels.

  5. Environmental Technology Verification Report: Pesticide spray drift reduction technologies--Evaluation of the verification protocol for low and high speed wind tunnel testing

    EPA Science Inventory

    Pesticide spray drift is defined as the movement of spray droplets through the air at the time of application or soon thereafter from the target site to any non- or off-target site, excluding pesticide movements by erosion, migration, volatility, or windblown soil particles after...

  6. The Electron Drift Instrument for MMS

    NASA Astrophysics Data System (ADS)

    Torbert, R. B.; Vaith, H.; Granoff, M.; Widholm, M.; Gaidos, J. A.; Briggs, B. H.; Dors, I. G.; Chutter, M. W.; Macri, J.; Argall, M.; Bodet, D.; Needell, J.; Steller, M. B.; Baumjohann, W.; Nakamura, R.; Plaschke, F.; Ottacher, H.; Hasiba, J.; Hofmann, K.; Kletzing, C. A.; Bounds, S. R.; Dvorsky, R. T.; Sigsbee, K.; Kooi, V.

    2016-03-01

    The Electron Drift Instrument (EDI) on the Magnetospheric Multiscale (MMS) mission measures the in-situ electric and magnetic fields using the drift of a weak beam of test electrons that, when emitted in certain directions, return to the spacecraft after one or more gyrations. This drift is related to the electric field and, to a lesser extent, the gradient in the magnetic field. Although these two quantities can be determined separately by use of different electron energies, for MMS regions of interest the magnetic field gradient contribution is negligible. As a by-product of the drift determination, the magnetic field strength and constraints on its direction are also determined. The present paper describes the scientific objectives, the experimental method, and the technical realization of the various elements of the instrument on MMS.

  7. Test and analysis of a stitched RFI graphite-epoxy panel with a fuel access door

    NASA Technical Reports Server (NTRS)

    Jegley, Dawn C.; Waters, W. Allen, Jr.

    1994-01-01

    A stitched RFI graphite-epoxy panel with a fuel access door was analyzed using a finite element analysis and loaded to failure in compression. The panel was initially 56-inches long and 36.75-inches wide and the oval access door was 18-inches long and 15-inches wide. The panel was impact damaged with impact energy of 100 ft-lb prior to compressive loading; however, no impact damage was detectable visually or by A-scan. The panel carried a failure load of 695,000 Ib and global failure strain of .00494 in/in. Analysis indicated the panel would fail due to collapse at a load of 688,100 Ib. The test data indicate that the maximum strain in a region near the access door was .0096 in/in and analysis indicates a local surface strain of .010 in/in at the panel's failure load. The panel did not fail through the impact damage, but instead failed through bolt holes for attachment of the access door in a region of high strain.

  8. Drift Degradation Analysis

    SciTech Connect

    D. Kicker

    2004-09-16

    Degradation of underground openings as a function of time is a natural and expected occurrence for any subsurface excavation. Over time, changes occur to both the stress condition and the strength of the rock mass due to several interacting factors. Once the factors contributing to degradation are characterized, the effects of drift degradation can typically be mitigated through appropriate design and maintenance of the ground support system. However, for the emplacement drifts of the geologic repository at Yucca Mountain, it is necessary to characterize drift degradation over a 10,000-year period, which is well beyond the functional period of the ground support system. This document provides an analysis of the amount of drift degradation anticipated in repository emplacement drifts for discrete events and time increments extending throughout the 10,000-year regulatory period for postclosure performance. This revision of the drift degradation analysis was developed to support the license application and fulfill specific agreement items between the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Department of Energy (DOE). The earlier versions of ''Drift Degradation Analysis'' (BSC 2001 [DIRS 156304]) relied primarily on the DRKBA numerical code, which provides for a probabilistic key-block assessment based on realistic fracture patterns determined from field mapping in the Exploratory Studies Facility (ESF) at Yucca Mountain. A key block is defined as a critical block in the surrounding rock mass of an excavation, which is removable and oriented in an unsafe manner such that it is likely to move into an opening unless support is provided. However, the use of the DRKBA code to determine potential rockfall data at the repository horizon during the postclosure period has several limitations: (1) The DRKBA code cannot explicitly apply dynamic loads due to seismic ground motion. (2) The DRKBA code cannot explicitly apply loads due to thermal stress. (3) The DRKBA

  9. SAA drift: Experimental results

    NASA Astrophysics Data System (ADS)

    Grigoryan, O. R.; Romashova, V. V.; Petrov, A. N.

    According to the paleomagnetic analysis there are variations of Earth’s magnetic field connected with magnetic moment changing. These variations affect on the South Atlantic Anomaly (SAA) location. Indeed different observations approved the existence of the SAA westward drift rate (0.1 1.0 deg/year) and northward drift rate (approximately 0.1 deg/year). In this work, we present the analysis of experimental results obtained in Scobeltsyn Institute of Nuclear Physics, Moscow State University (SINP MSU) onboard different Earth’s artificial satellites (1972 2003). The fluxes of protons with energy >50 MeV, gamma quanta with energy >500 keV and neutrons with energy 0.1 1.0 MeV in the SAA region have been analyzed. The mentioned above experimental data were obtained onboard the orbital stations Salut-6 (1979), MIR (1991, 1998) and ISS (2003) by the similar experimental equipment. The comparison of the data obtained during these two decades of investigations confirms the fact that the SAA drifts westward. Moreover the analysis of fluxes of electrons with energy about hundreds keV (Cosmos-484 (1972) and Active (Interkosmos-24, 1991) satellites) verified not only the SAA westward drift but northward drift also.

  10. Changes in constructed Brassica communities treated with glyphosate drift.

    PubMed

    Watrud, Lidia S; King, George; Londo, Jason P; Colasanti, Ricardo; Smith, Bonnie M; Waschmann, Ronald S; Lee, E Henry

    2011-03-01

    We constructed a mixed-species community designed to simulate roadside and field edge plant communities and exposed it to glyphosate drift in order to test three hypotheses: (1) higher fitness in transgenic Brassica carrying the CP4 EPSPS transgene that confers resistance to glyphosate will result in significant changes in the plant community relative to control communities; (2) given repeated years of glyphosate drift selective pressure, the increased fitness of the transgenic Brassica with CP4 EPSPS will contribute to an increase in the proportion of transgenic progeny produced in plant communities; and (3) the increased fitness of Brassica carrying the CP4 EPSPS transgene will contribute to decreased levels of mycorrhizal infection and biomass in a host species (Trifolium incarnatum). Due to regulatory constraints that prevented the use of outdoor plots for our studies, in 2005 we established multispecies communities in five large cylindrical outdoor sunlit mesocosms (plastic greenhouses) designed for pollen confinement. Three of the community members were sexually compatible Brassica spp.: transgenic glyphosate-resistant canola (B. napus) cultivar (cv.) RaideRR, glyphosate-sensitive non-transgenic B. napus cv. Sponsor, and a weedy B. rapa (GRIN Accession 21735). Additional plant community members were the broadly distributed annual weeds Digitaria sanguinalis, Panicum capillare, and Lapsana communis. Once annually in 2006 and 2007, two mesocosms were sprayed with glyphosate at 10% of the field application rate to simulate glyphosate drift as a selective pressure. After two years, changes were observed in community composition, plant density, and biomass in both control and treatment mesocosms. In control mesocosms, the weed D. sanguinalis (crabgrass) began to dominate. In glyphosate drift-treated mesocosms, Brassica remained the dominant genus and the incidence of the CP4 EPSPS transgene increased in the community. Shoot biomass and mycorrhizal infection in

  11. Seeking wider access to HIV testing for adolescents in sub-Saharan Africa.

    PubMed

    Sam-Agudu, Nadia A; Folayan, Morenike O; Ezeanolue, Echezona E

    2016-06-01

    More than 80% of the HIV-infected adolescents live in sub-Saharan Africa. Acquired immune deficiency syndrome (AIDS)-related mortality has increased among adolescents 10-19 y old. The impact is highest in sub-Saharan Africa, where >80% of HIV-infected adolescents live. The World Health Organization has cited inadequate access to HIV testing and counseling (HTC) as a contributing factor to AIDS-related adolescent deaths, most of which occur in sub-Saharan Africa. This review focuses on studies conducted in high adolescent HIV-burden countries targeted by the "All In to End Adolescent AIDS" initiative, and describes barriers to adolescent HTC uptake and coverage. Fear of stigma and family reaction, fear of the impact of a positive diagnosis, perceived risk with respect to sexual exposure, poor attitudes of healthcare providers, and parental consent requirements are identified as major impediments. Most-at-risk adolescents for HIV infection and missed opportunities for testing include, those perinatally infected, those with early sexual debut, high mobility and multiple/older partners, and pregnant and nonpregnant females. Regional analyses show relatively low adolescent testing rates and more restrictive consent requirements for HTC in West and Central Africa as compared to East and southern Africa. Actionable recommendations for widening adolescent access to HTC and therefore timely care include minimizing legal consent barriers, healthcare provider training, parental education and involvement, and expanding testing beyond healthcare facilities. PMID:26882367

  12. Negotiating multiple barriers: health workers' access to counselling, testing and treatment in Malawi.

    PubMed

    Namakhoma, Ireen; Bongololo, Grace; Bello, George; Nyirenda, Lot; Phoya, Anne; Phiri, Sam; Theobald, Sally; Obermeyer, Carla Makhlouf

    2010-01-01

    Malawi is facing a severe HIV and AIDS epidemic with an estimated 12% of its population living with the virus. Health workers are on the front lines of the HIV epidemic and they face the risk of HIV infection in both their personal and professional lives. This mixed method study aimed to explore the enablers and barriers to HIV counselling and testing and antiretroviral therapy by health workers in Malawi. After qualitative data were collected through in-depth interviews with health workers in the Mchinji and Nsanje districts, a survey questionnaire was constructed and administered to 906 health workers in eight districts in Malawi. A majority (76%) of health workers surveyed reported having undergone HIV testing and counselling, of whom 74% reported repeat testing. A striking result of the study is that 22% of health workers reported testing after occupational exposure to HIV. The proportions of respondents reporting that they tested after experiencing symptoms, or self-testing for HIV were 11% each. The in-depth interviews and the survey revealed multiple challenges that health workers face to accessing HIV testing, counselling and treatment, including fear of a positive result, fear of stigma and lack of confidentiality. Additional barriers included health workers' personal acquaintance with those conducting testing, along with their perception of being "role models" which could exacerbate their fears about confidentiality. Given health workers' critical role in HIV delivery in Malawi, there is need to develop solutions to help health workers overcome these barriers. PMID:20680862

  13. Impact of Gene Patents and Licensing Practices on Access to Genetic Testing for Hereditary Hemochromatosis

    PubMed Central

    Chandrasekharan, Subhashini; Pitlick, Emily; Heaney, Christopher; Cook-Deegan, Robert

    2010-01-01

    Hereditary hemochromatosis (HH) is an iron metabolism disorder that leads to excess iron buildup, especially in the heart, liver, and pancreas. Mutations in the HFE gene are the single most common cause of HH, which can be treated effectively if diagnosed early. Patents cover the HFE gene, related proteins, screening methods, and testing kits. Most initial testing for HH is biochemical, but HFE DNA testing or genotyping is used to confirm a diagnosis of inherited hemochromatosis. Concerns over patents covering HFE testing emerged in 2002, when scholars argued that exclusive licensing and the patent-enabled sole provider model then in place led to high prices and limited access. Critics of the sole provider model noted that the test was available at multiple laboratories prior to the enforcement of patents. By 2007, however, Bio-Rad, Limited, acquired the key intellectual property and sub-licensed it widely. In part because of broad, non-exclusive licensing, there are now multiple providers and testing technologies, and research continues. This case study illustrates how both changes in intellectual property ownership and evolving clinical utility of HFE genetic testing in the last decade have effected the licensing of patents and availability of genetic testing. PMID:20393306

  14. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Research Team

    NASA Technical Reports Server (NTRS)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage raft empennage.

  15. Continental drift before 1900.

    PubMed

    Rupke, N A

    1970-07-25

    The idea that Francis Bacon and other seventeenth and eighteenth century thinkers first conceived the notion of continental drift does not stand up to close scrutiny. The few authors who expressed the idea viewed the process as a catastrophic event. PMID:16057953

  16. High resolution drift chambers

    SciTech Connect

    Va'vra, J.

    1985-07-01

    High precision drift chambers capable of achieving less than or equal to 50 ..mu..m resolutions are discussed. In particular, we compare so called cool and hot gases, various charge collection geometries, several timing techniques and we also discuss some systematic problems. We also present what we would consider an ''ultimate'' design of the vertex chamber. 50 refs., 36 figs., 6 tabs.

  17. IN DRIFT CORROSION PRODUCTS

    SciTech Connect

    D.M. Jolley

    1999-12-02

    As directed by a written development plan (CRWMS M&O 1999a), a conceptual model for steel and corrosion products in the engineered barrier system (EBS) is to be developed. The purpose of this conceptual model is to assist Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift, thus allowing PAO to provide a more detailed and complete in-drift geochemical model abstraction and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near-Field Environment (NFE) Revision 2 (NRC 1999). This document provides the conceptual framework for the in-drift corrosion products sub-model to be used in subsequent PAO analyses including the EBS physical and chemical model abstraction effort. This model has been developed to serve as a basis for the in-drift geochemical analyses performed by PAO. However, the concepts discussed within this report may also apply to some near and far-field geochemical processes and may have conceptual application within the unsaturated zone (UZ) and saturated zone (SZ) transport modeling efforts.

  18. Prior extended daily access to cocaine elevates the reward threshold in a conditioned place preference test.

    PubMed

    Su, Zu-In; Wenzel, Jennifer; Ettenberg, Aaron; Ben-Shahar, Osnat

    2014-09-01

    We have previously shown that extended-access subjects exhibit heightened motivation for cocaine in the runway model, as reflected by reduced number of retreats. This heightened motivation could reflect either an increase in cocaine-induced reward or a decrease in cocaine-induced aversion. The current experiment was therefore devised to assess the cocaine-induced reward and aversion in extended-access rats using a place conditioning test. Rats trained to lever press for intravenous (IV) cocaine (0.25 mg/infusion) were provided 6-hour daily access to the drug over 10 days. Lever pressing in control subjects produced IV infusions of saline. Following drug self-administration, subjects underwent place conditioning for the immediate or delayed effects of cocaine (1.0 or 2.5 mg/kg, IV). In control subjects, the immediate effects of the low dose of cocaine produced conditioned places preferences (CPPs), while the delayed effects produced conditioned place aversions (CPAs). In contrast, the animals receiving low cocaine dose for 6 hours, exhibited place aversions but not preferences; an effect that was reversed when the dose of cocaine was increased. Additionally, in the 6-hour group, delayed conditioning was associated with a reduction in zif268 immunoreactivity in the medial prefrontal cortex and nucleus accumbens shell while immediate conditioning was associated with an increase in zif268-positive cells in the central nucleus of the amygdala. Collectively, these data suggest that extended daily access to cocaine produces a shift in the subject's perceived reward threshold that is paralleled by alterations in the activity of both the reward and stress pathways. PMID:23634951

  19. Dike Propagation Near Drifts

    SciTech Connect

    NA

    2002-03-04

    The purpose of this Analysis and Model Report (AMR) supporting the Site Recommendation/License Application (SR/LA) for the Yucca Mountain Project is the development of elementary analyses of the interactions of a hypothetical dike with a repository drift (i.e., tunnel) and with the drift contents at the potential Yucca Mountain repository. This effort is intended to support the analysis of disruptive events for Total System Performance Assessment (TSPA). This AMR supports the Process Model Report (PMR) on disruptive events (CRWMS M&O 2000a). This purpose is documented in the development plan (DP) ''Coordinate Modeling of Dike Propagation Near Drifts Consequences for TSPA-SR/LA'' (CRWMS M&O 2000b). Evaluation of that Development Plan and the work to be conducted to prepare Interim Change Notice (ICN) 1 of this report, which now includes the design option of ''Open'' drifts, indicated that no revision to that DP was needed. These analyses are intended to provide reasonable bounds for a number of expected effects: (1) Temperature changes to the waste package from exposure to magma; (2) The gas flow available to degrade waste containers during the intrusion; (3) Movement of the waste package as it is displaced by the gas, pyroclasts and magma from the intruding dike (the number of packages damaged); (4) Movement of the backfill (Backfill is treated here as a design option); (5) The nature of the mechanics of the dike/drift interaction. These analyses serve two objectives: to provide preliminary analyses needed to support evaluation of the consequences of an intrusive event and to provide a basis for addressing some of the concerns of the Nuclear Regulatory Commission (NRC) expressed in the Igneous Activity Issue Resolution Status Report.

  20. Proportional drift tubes for large area muon detectors

    NASA Technical Reports Server (NTRS)

    Cho, C.; Higashi, S.; Hiraoka, N.; Maruyama, A.; Okusawa, T.; Sato, T.; Suwada, T.; Takahashi, T.; Umeda, H.

    1985-01-01

    A proportional drift chamber which consists of eight rectangular drift tubes with cross section of 10 cm x 5 cm, a sense wire of 100 micron phi gold-plated tungsten wire and the length of 6 m, was tested using cosmic ray muons. Spatial resolution (rms) is between 0.5 and 1 mm over drift space of 50 mm, depending on incident angle and distance from sense wire.

  1. An Universal packaging technique for low-drift implantable pressure sensors.

    PubMed

    Kim, Albert; Powell, Charles R; Ziaie, Babak

    2016-04-01

    Monitoring bodily pressures provide valuable diagnostic and prognostic information. In particular, long-term measurement through implantable sensors is highly desirable in situations where percutaneous access can be complicated or dangerous (e.g., intracranial pressure in hydrocephalic patients). In spite of decades of progress in the fabrication of miniature solid-state pressure sensors, sensor drift has so far severely limited their application in implantable systems. In this paper, we report on a universal packaging technique for reducing the sensor drift. The described method isolates the pressure sensor from a major source of drift, i.e., contact with the aqueous surrounding environment, by encasing the sensor in a silicone-filled medical-grade polyurethane balloon. In-vitro soak tests for 100 days using commercial micromachined piezoresistive pressure sensors demonstrate a stable operation with the output remaining within 1.8 cmH2O (1.3 mmHg) of a reference pressure transducer. Under similar test conditions, a non-isolated sensor fluctuates between 10 and 20 cmH2O (7.4-14.7 mmHg) of the reference, without ever settling to a stable operation regime. Implantation in Ossabow pigs demonstrate the robustness of the package and its in-vivo efficacy in reducing the baseline drift. PMID:26945864

  2. Impact of Gene Patents and Licensing Practices on Access to Genetic Testing for Cystic Fibrosis

    PubMed Central

    Chandrasekharan, Subhashini; Heaney, Christopher; James, Tamara; Conover, Chris; Cook-Deegan, Robert

    2010-01-01

    Cystic fibrosis (CF) is one of the most commonly tested autosomal recessive disorders in the US. Clinical CF is associated with mutations in the CFTR gene, of which the most common mutation among Caucasians, ΔF508, was identified in 1989. The University of Michigan, Johns Hopkins University, and the Hospital for Sick Children, where much of the initial research occurred, hold key patents for CF genetic sequences, mutations and methods for detecting them. Several patents including the one that covers detection of the ΔF508 mutation are jointly held by the University of Michigan and the Hospital for Sick Children in Toronto, with Michigan administering patent licensing in the US. The University of Michigan broadly licenses the ΔF508 patent for genetic testing with over 60 providers of genetic testing to date. Genetic testing is now used in newborn screening, diagnosis, and reproductive decisions. Interviews with key researchers and intellectual property managers, a survey of laboratories’ prices for CF genetic testing, a review of literature on CF tests’ cost effectiveness, and a review of the developing market for CF testing provide no evidence that patents have significantly hindered access to genetic tests for CF or prevented financially cost-effective screening. Current licensing practices for cystic fibrosis (CF) genetic testing appear to facilitate both academic research and commercial testing. More than one thousand different CFTR mutations have been identified, and research continues to determine their clinical significance. Patents have been nonexclusively licensed for diagnostic use, and have been variably licensed for gene transfer and other therapeutic applications. The Cystic Fibrosis Foundation has been engaged in licensing decisions, making CF a model of collaborative and cooperative patenting and licensing practice. PMID:20393308

  3. Multiple user access and testing for PreNotiS: a fast mobile event reporting solution

    NASA Astrophysics Data System (ADS)

    Chan, Michael; Kumar, Abhinav; Akopian, David; Agaian, Sos S.

    2011-06-01

    The PreNotiS (preventive notification system) was proposed to address the current lack in consumer prevention and disaster informatics systems. The underscore of this letter is to propose PreNotiS as a provision of trusted proxies of information sourcing to be integral to the disaster informatics framework. To promote loose coupling among subsystems, PreNotiS has evolved into a model-view-controller (MVC) architecture via object-oriented incremental prototyping. The MVC specifies how all subsystems and how they interact with each other. A testing framework is also proposed for the PreNotiS to verify multiple concurrent user access which might be observable during disasters. The framework relies on conceptually similar self-test modules to help with serviceability.

  4. Redefining Accessibility on High-Stakes Tests for Postsecondary College Students with Learning Disabilities in an Era of Technology

    ERIC Educational Resources Information Center

    Banerjee, Manju; Gregg, Noel

    2008-01-01

    Unprecedented increases in the use of technologies throughout postsecondary education and the workplace are redefining traditional concepts of accessibility during testing for college students with learning disabilities. High stakes testing practices are under pressure to change. The challenge for professionals is to ensure that tests are designed…

  5. When access is an issue: exploring barriers to predictive testing for Huntington disease in British Columbia, Canada

    PubMed Central

    Hawkins, Alice K; Creighton, Susan; Hayden, Michael R

    2013-01-01

    Predictive testing (PT) for Huntington disease (HD) requires several in-person appointments. This requirement may be a barrier to testing so that at risk individuals do not realize the potential benefits of PT. To understand the obstacles to PT in terms of the accessibility of services, as well as exploring mechanisms by which this issue may be addressed, we conducted an interview study of individuals at risk for HD throughout British Columbia, Canada. Results reveal that the accessibility of PT can be a barrier for two major reasons: distance and the inflexibility of the testing process. Distance is a structural barrier, and relates to the time and travel required to access PT, the financial and other opportunity costs associated with taking time away from work and family to attend appointments and the stress of navigating urban centers. The inflexibility of the testing process barrier relates to the emotional and psychological accessibility of PT. The results of the interview study reveal that there are access barriers to PT that deter individuals from receiving the support, information and counseling they require. What makes accessibility of PT services important is not just that it may result in differences in quality of life and care, but because these differences may be addressed with creative and adaptable solutions in the delivery of genetic services. The study findings underscore the need for us to rethink and personalize the way we deliver such services to improve access issues to prevent inequities in the health care system. PMID:22781094

  6. Diogene pictorial drift chamber

    SciTech Connect

    Gosset, J.

    1984-01-01

    A pictorial drift chamber, called DIOGENE, has been installed at Saturne in order to study central collisions of high energy heavy ions. It has been adapted from the JADE internal detector, with two major differences to be taken into account. First, the center-of-mass of these collisions is not identical to the laboratory reference frame. Second, the energy loss and the momentum ranges of the particles to be detected are different from the ones in JADE. It was also tried to keep the cost as small as possible, hence the choice of minimum size and minimum number of sensitive wires. Moreover the wire planes are shifted from the beam axis: this trick helps very much to quickly reject the bad tracks caused by the ambiguity of measuring drift distances (positive or negative) through times (always positive).

  7. Improving Inpatient Surveys: Web-Based Computer Adaptive Testing Accessed via Mobile Phone QR Codes

    PubMed Central

    2016-01-01

    Background The National Health Service (NHS) 70-item inpatient questionnaire surveys inpatients on their perceptions of their hospitalization experience. However, it imposes more burden on the patient than other similar surveys. The literature shows that computerized adaptive testing (CAT) based on item response theory can help shorten the item length of a questionnaire without compromising its precision. Objective Our aim was to investigate whether CAT can be (1) efficient with item reduction and (2) used with quick response (QR) codes scanned by mobile phones. Methods After downloading the 2008 inpatient survey data from the Picker Institute Europe website and analyzing the difficulties of this 70-item questionnaire, we used an author-made Excel program using the Rasch partial credit model to simulate 1000 patients’ true scores followed by a standard normal distribution. The CAT was compared to two other scenarios of answering all items (AAI) and the randomized selection method (RSM), as we investigated item length (efficiency) and measurement accuracy. The author-made Web-based CAT program for gathering patient feedback was effectively accessed from mobile phones by scanning the QR code. Results We found that the CAT can be more efficient for patients answering questions (ie, fewer items to respond to) than either AAI or RSM without compromising its measurement accuracy. A Web-based CAT inpatient survey accessed by scanning a QR code on a mobile phone was viable for gathering inpatient satisfaction responses. Conclusions With advances in technology, patients can now be offered alternatives for providing feedback about hospitalization satisfaction. This Web-based CAT is a possible option in health care settings for reducing the number of survey items, as well as offering an innovative QR code access. PMID:26935793

  8. Testing flow-through air samplers for use in near-field vapour drift studies by measuring pyrimethanil in air after spraying.

    PubMed

    Geoghegan, Trudyanne S; Hageman, Kimberly J; Hewitt, Andrew J

    2014-03-01

    Pesticide volatilisation and subsequent vapour drift reduce a pesticide's efficiency and contribute to environmental contamination. High-volume air samplers (HVSs) are often used to measure pesticide concentrations in air but these samplers are expensive to purchase and require network electricity, limiting the number and type of sites where they can be deployed. The flow-through sampler (FTS) presents an opportunity to overcome these limitations. The FTS is a wind-driven passive sampler that has been developed to quantify organic contaminants in remote ecosystems. FTSs differ from other passive samplers in that they turn into the wind and use the wind to draw air through the sampling media. The main objective of this work was to evaluate the FTS in a near-field pesticide vapour drift study by comparing the concentrations of pyrimethanil in air measured using one HVS and three FTSs placed in the same location. Pyrimethanil was sprayed onto a vineyard as part of normal pest management procedures. Air samples were collected every eight hours for 48 h. The volume of air sampled by the FTSs was calculated using the measured relationship between ambient wind speed and the wind speed inside the sampler as determined with a separate wind tunnel study. The FTSs sampled 1.7 to 40.6 m(3) of air during each 8 h sampling period, depending on wind speed, whereas the mean volume sampled by the HVS was 128.7 m(3). Mean pyrimethanil concentrations ranged from 0.4 to 3.2 μg m(-3) of air. Inter-sampler reproducibility, as represented by percent relative standard deviation, for the three FTSs was ∼20%. The largest difference in FTS-derived versus HVS-derived pyrimethanil concentrations occurred during the lowest wind-speed period. During this period, it is likely that the FTS predominately acted like a traditional diffusion-based passive sampler. As indicated by both types of sampler, pyrimethanil concentrations in air changed by a factor of ∼2 during the two days after spaying

  9. Construction Progress of the S-IC Test Stand-Block House Access Tunnel

    NASA Technical Reports Server (NTRS)

    1962-01-01

    At its founding, the Marshall Space Flight Center (MSFC) inherited the Army's Jupiter and Redstone test stands, but much larger facilities were needed for the giant stages of the Saturn V. From 1960 to 1964, the existing stands were remodeled and a sizable new test area was developed. The new comprehensive test complex for propulsion and structural dynamics was unique within the nation and the free world, and they remain so today because they were constructed with foresight to meet the future as well as on going needs. Construction of the S-IC Static test stand complex began in 1961 in the west test area of MSFC, and was completed in 1964. The S-IC static test stand was designed to develop and test the 138-ft long and 33-ft diameter Saturn V S-IC first stage, or booster stage, weighing in at 280,000 pounds. Required to hold down the brute force of a 7,500,000-pound thrust produced by 5 F-1 engines, the S-IC static test stand was designed and constructed with the strength of hundreds of tons of steel and 12,000,000 pounds of cement, planted down to bedrock 40 feet below ground level. The foundation walls, constructed with concrete and steel, are 4 feet thick. The base structure consists of four towers with 40-foot-thick walls extending upward 144 feet above ground level. The structure was topped by a crane with a 135-foot boom. With the boom in the upright position, the stand was given an overall height of 405 feet, placing it among the highest structures in Alabama at the time. In addition to the stand itself, related facilities were constructed during this time. Built directly east of the test stand was the Block House, which served as the control center for the test stand. The two were connected by a narrow access tunnel which housed the cables for the controls. This construction photo taken August 17, 1962 depicts a view of the Block House from the test stand site. The tunnel opening is visible in the forefront center of the photo.

  10. Laboratory Course on Drift Chambers

    NASA Astrophysics Data System (ADS)

    García-Ferreira, Ix-B.; García-Herrera, J.; Villaseñor, L.

    2006-09-01

    Drift chambers play an important role in particle physics experiments as tracking detectors. We started this laboratory course with a brief review of the theoretical background and then moved on to the the experimental setup which consisted of a single-sided, single-cell drift chamber. We also used a plastic scintillator paddle, standard P-10 gas mixture (90% Ar, 10% CH4) and a collimated 90Sr source. During the laboratory session the students performend measurements of the following quantities: a) drift velocities and their variations as function of the drift field; b) gas gains and c) diffusion of electrons as they drifted in the gas.

  11. Construction Progress of the S-IC Test Stand-Block House Access Tunnel

    NASA Technical Reports Server (NTRS)

    1962-01-01

    At its founding, the Marshall Space Flight Center (MSFC) inherited the Army's Jupiter and Redstone test stands, but much larger facilities were needed for the giant stages of the Saturn V. From 1960 to 1964, the existing stands were remodeled and a sizable new test area was developed. The new comprehensive test complex for propulsion and structural dynamics was unique within the nation and the free world, and they remain so today because they were constructed with foresight to meet the future as well as on going needs. Construction of the S-IC Static test stand complex began in 1961 in the west test area of MSFC, and was completed in 1964. The S-IC static test stand was designed to develop and test the 138-ft long and 33-ft diameter Saturn V S-IC first stage, or booster stage, weighing in at 280,000 pounds. Required to hold down the brute force of a 7,500,000-pound thrust produced by 5 F-1 engines, the S-IC static test stand was designed and constructed with the strength of hundreds of tons of steel and 12,000,000 pounds of cement, planted down to bedrock 40 feet below ground level. The foundation walls, constructed with concrete and steel, are 4 feet thick. The base structure consists of four towers with 40-foot-thick walls extending upward 144 feet above ground level. The structure was topped by a crane with a 135-foot boom. With the boom in the upright position, the stand was given an overall height of 405 feet, placing it among the highest structures in Alabama at the time. In addition to the stand itself, related facilities were constructed during this time. Built directly east of the test stand was the Block House, which served as the control center for the test stand. The two were connected by a narrow access tunnel which housed the cables for the controls. Construction of the tunnel is depicted in this photo taken June 13, 1962.

  12. Construction Progress of the S-IC Test Stand-Block House Access Tunnel

    NASA Technical Reports Server (NTRS)

    1962-01-01

    At its founding, the Marshall Space Flight Center (MSFC) inherited the Army's Jupiter and Redstone test stands, but much larger facilities were needed for the giant stages of the Saturn V. From 1960 to 1964, the existing stands were remodeled and a sizable new test area was developed. The new comprehensive test complex for propulsion and structural dynamics was unique within the nation and the free world, and they remain so today because they were constructed with foresight to meet the future as well as on going needs. Construction of the S-IC Static test stand complex began in 1961 in the west test area of MSFC, and was completed in 1964. The S-IC static test stand was designed to develop and test the 138-ft long and 33-ft diameter Saturn V S-IC first stage, or booster stage, weighing in at 280,000 pounds. Required to hold down the brute force of a 7,500,000-pound thrust produced by 5 F-1 engines, the S-IC static test stand was designed and constructed with the strength of hundreds of tons of steel and 12,000,000 pounds of cement, planted down to bedrock 40 feet below ground level. The foundation walls, constructed with concrete and steel, are 4 feet thick. The base structure consists of four towers with 40-foot-thick walls extending upward 144 feet above ground level. The structure was topped by a crane with a 135-foot boom. With the boom in the upright position, the stand was given an overall height of 405 feet, placing it among the highest structures in Alabama at the time. In addition to the stand itself, related facilities were constructed during this time. Built directly east of the test stand was the Block House, which served as the control center for the test stand. The two were connected by a narrow access tunnel which housed the cables for the controls. This construction photo, taken October 26, 1962, depicts a view of the Block House tunnel opening.

  13. Construction Progress of the S-IC Test Stand-Access Tunnel

    NASA Technical Reports Server (NTRS)

    1962-01-01

    At its founding, the Marshall Space Flight Center (MSFC) inherited the Army's Jupiter and Redstone test stands, but much larger facilities were needed for the giant stages of the Saturn V. From 1960 to 1964, the existing stands were remodeled and a sizable new test area was developed. The new comprehensive test complex for propulsion and structural dynamics was unique within the nation and the free world, and they remain so today because they were constructed with foresight to meet the future as well as on going needs. Construction of the S-IC Static test stand complex began in 1961 in the west test area of MSFC, and was completed in 1964. The S-IC static test stand was designed to develop and test the 138-ft long and 33-ft diameter Saturn V S-IC first stage, or booster stage, weighing in at 280,000 pounds. Required to hold down the brute force of a 7,500,000-pound thrust produced by 5 F-1 engines, the S-IC static test stand was designed and constructed with the strength of hundreds of tons of steel and 12,000,000 pounds of cement, planted down to bedrock 40 feet below ground level. The foundation walls, constructed with concrete and steel, are 4 feet thick. The base structure consists of four towers with 40-foot-thick walls extending upward 144 feet above ground level. The structure was topped by a crane with a 135-foot boom. With the boom in the upright position, the stand was given an overall height of 405 feet, placing it among the highest structures in Alabama at the time. In addition to the stand itself, related facilities were constructed during this time. Built directly east of the test stand was the Block House, which served as the control center for the test stand. The two were connected by a narrow tunnel which housed the cables for the controls. This photograph, taken on May 21, 1962 depicts the access tunnel construction.

  14. Using Institutional Theory To Reframe Research on Academic Drift.

    ERIC Educational Resources Information Center

    Morphew, Christopher C.; Huisman, Jeroen

    2002-01-01

    Examines patterns of academic drift (a drift toward the structure and norms typical of more prestigious universities) in multiple higher education systems and tests the concept of "isomorphism in organizational fields" as discussed in institutional theory. Argues that the theoretical framework provided by institutional theory presents a useful…

  15. 40 CFR 161.440 - Spray drift data requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Spray drift data requirements. 161.440... DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Data Requirement Tables § 161.440 Spray... determine the aerial spray drift data requirements and the substance to be tested. Kind of data required...

  16. 40 CFR 161.440 - Spray drift data requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Spray drift data requirements. 161.440... DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Data Requirement Tables § 161.440 Spray... determine the aerial spray drift data requirements and the substance to be tested. Kind of data required...

  17. Inner and outer waste storage vaults with leak-testing accessibility

    SciTech Connect

    Splinter, B.C.

    1985-04-23

    A storage arrangement for waste materials of the type which tend to pollute the environment consists of a waterproof reinforced concrete vault, preferably located underground, and a permanent reinforced concrete storage vault within the underground vault and spaced from the walls thereof by a water lock. Sealed containers filled with chemical or nuclear waste are deposited in the permanent storage vault and sealed therein with bitumen. The underground vault is provided with an access opening to the water lock to enable testing of the water periodically for contamination due to leakage from the permanent storage vault. If no leakage is evident after a predetermined time period has elapsed, the permanent storage vault is removed from the underground vault and shipped to a permanent storage site.

  18. Drift in toroidal configurations

    NASA Astrophysics Data System (ADS)

    Evangelidis, E. A.

    1990-12-01

    This paper considers possible mechanisms involved in amplifying the drift velocity of plasma particles, under conditions of toroidal geometry. It is shown that particles constrained to move on an axisymmetric circular spheroidal surface, develop a sinusoidal motion with a characteristic frequency which depends on the energy of the particles, the value of the isoflux surface, and the value of the general momentum. It is also shown that the incorporation of the effects of toroidal geometry in the Lorentz equation produces a nonambipolar charge-dependent particle flux amplified by a factor 2(q/epsilon) squared.

  19. Spaced antenna drift

    NASA Technical Reports Server (NTRS)

    Royrvik, O.

    1983-01-01

    It has been suggested that the spaced antenna drift (SAD) technique could be successfully used by VHF radars and that it would be superior to a Doppler-beam-swinging (DBS) technique because it would take advantage of the aspect sensitivity of the scattered signal, and might also benefit from returns from single meteors. It appears, however, that the technique suffers from several limitations. On the basis of one SAD experiment performed at the very large Jicamarca radar, it is concluded that the SAD technique can be compared in accuracy to the DBS technique only if small antenna dimensions are used.

  20. Develop and test a solvent accessible surface area-based model in conformational entropy calculations.

    PubMed

    Wang, Junmei; Hou, Tingjun

    2012-05-25

    It is of great interest in modern drug design to accurately calculate the free energies of protein-ligand or nucleic acid-ligand binding. MM-PBSA (molecular mechanics Poisson-Boltzmann surface area) and MM-GBSA (molecular mechanics generalized Born surface area) have gained popularity in this field. For both methods, the conformational entropy, which is usually calculated through normal-mode analysis (NMA), is needed to calculate the absolute binding free energies. Unfortunately, NMA is computationally demanding and becomes a bottleneck of the MM-PB/GBSA-NMA methods. In this work, we have developed a fast approach to estimate the conformational entropy based upon solvent accessible surface area calculations. In our approach, the conformational entropy of a molecule, S, can be obtained by summing up the contributions of all atoms, no matter they are buried or exposed. Each atom has two types of surface areas, solvent accessible surface area (SAS) and buried SAS (BSAS). The two types of surface areas are weighted to estimate the contribution of an atom to S. Atoms having the same atom type share the same weight and a general parameter k is applied to balance the contributions of the two types of surface areas. This entropy model was parametrized using a large set of small molecules for which their conformational entropies were calculated at the B3LYP/6-31G* level taking the solvent effect into account. The weighted solvent accessible surface area (WSAS) model was extensively evaluated in three tests. For convenience, TS values, the product of temperature T and conformational entropy S, were calculated in those tests. T was always set to 298.15 K through the text. First of all, good correlations were achieved between WSAS TS and NMA TS for 44 protein or nucleic acid systems sampled with molecular dynamics simulations (10 snapshots were collected for postentropy calculations): the mean correlation coefficient squares (R²) was 0.56. As to the 20 complexes, the TS

  1. Testing a bedside personal computer Clinical Care Classification System for nursing students using Microsoft Access.

    PubMed

    Feeg, Veronica D; Saba, Virginia K; Feeg, Alan N

    2008-01-01

    This study tested a personal computer-based version of the Sabacare Clinical Care Classification System on students' performance of charting patient care plans. The application was designed as an inexpensive alternative to teach electronic charting for use on any laptop or personal computer with Windows and Microsoft Access. The data-based system was tested in a randomized trial with the control group using a type-in text-based-only system also mounted on a laptop at the bedside in the laboratory. Student care plans were more complete using the data-based system over the type-in text version. Students were more positive but not necessarily more efficient with the data-based system. The results demonstrate that the application is effective for improving student nursing care charting using the nursing process and capturing patient care information with a language that is standardized and ready for integration with other patient electronic health record data. It can be implemented on a bedside stand in the clinical laboratory or used to aggregate care planning over a student's clinical experience. PMID:19047883

  2. Stability evaluation of the Panel 1 rooms and the E140 drift at WIPP

    SciTech Connect

    Maleki, H.; Chaturvedi, L.

    1996-08-01

    WIPP, intended for underground permanent disposal of defense transuranic waste, is located 40 km east of Carlsbad at a depth of 655 m in the salt beds of the 600-m thick Permian Salado Formation. It will consist of 56 ``rooms`` each 91.5 m long, 10 m wide, and 4 m high, grouped in 8 ``panels`` of 7 rooms each. About 7.5 km of access drifts will also be provided. Excavation began in 1982 and surface/access/test facilities and one panel were completed by 1988, many years before it could be used. Current plans are to start emplacing waste in WIPP in 1998 and continue for 35 years. The north- south drift E140 is the widest (25 ft) of the four main north-south drifts and is the main north-south passage. Plans to conduct experiments with waste in 1993 were abandoned, and the plan now is to use panel 1 for permanent disposal of waste starting in 1998. The stability evaluation resulted in the conclusion that, while it would be possible to safely use portions of panel 1 for waste emplacement, it would be best to abandon panel 1 and mine a new panel after the decision has been made to use WIPP as a repository and the necessary permits obtained.

  3. Fingermark ridge drift.

    PubMed

    De Alcaraz-Fossoul, Josep; Roberts, Katherine A; Feixat, Carme Barrot; Hogrebe, Gregory G; Badia, Manel Gené

    2016-01-01

    Distortions of the fingermark topography are usually considered when comparing latent and exemplar fingerprints. These alterations are characterized as caused by an extrinsic action, which affects entire areas of the deposition and alters the overall flow of a series of contiguous ridges. Here we introduce a novel visual phenomenon that does not follow these principles, named fingermark ridge drift. An experiment was designed that included variables such as type of secretion (eccrine and sebaceous), substrate (glass and polystyrene), and degrees of exposure to natural light (darkness, shade, and direct light) indoors. Fingermarks were sequentially visualized with titanium dioxide powder, photographed and analyzed. The comparison between fresh and aged depositions revealed that under certain environmental conditions an individual ridge could randomly change its original position regardless of its unaltered adjacent ridges. The causes of the drift phenomenon are not well understood. We believe it is exclusively associated with intrinsic natural aging processes of latent fingermarks. This discovery will help explain the detection of certain dissimilarities at the minutiae/ridge level; determine more accurate "hits"; identify potentially erroneous corresponding points; and rethink identification protocols, especially the criteria of "no single minutiae discrepancy" for a positive identification. PMID:26646735

  4. Fracture mapping at the Spent Fuel Test-Climax

    SciTech Connect

    Wilder, D.G.; Yow, J.L. Jr.

    1981-05-01

    Mapping of geologic discontinuities has been done in several phases at the Spent Fuel Test-Climax (SFT-C) in the granitic Climax stock at the Nevada Test Site. Mapping was carried out in the tail drift, access drift, canister drift, heater drifts, instrumentation alcove, and receiving room. The fractures mapped as intersecting a horizontal datum in the canister and heater drifts are shown on one figure. Fracture sketch maps have been compiled as additional figures. Geologic mapping efforts were scheduled around and significantly impacted by the excavation and construction schedules. Several people were involved in the mapping, and over 2500 geologic discontinuities were mapped, including joints, shears, and faults. Some variance between individuals` mapping efforts was noticed, and the effects of various magnetic influences upon a compass were examined. The examination of compass errors improved the credibility of the data. The compass analysis work is explained in Appendix A. Analysis of the fracture data will be presented in a future report.

  5. Dealing with the unexpected: consumer responses to direct-access BRCA mutation testing.

    PubMed

    Francke, Uta; Dijamco, Cheri; Kiefer, Amy K; Eriksson, Nicholas; Moiseff, Bianca; Tung, Joyce Y; Mountain, Joanna L

    2013-01-01

    appreciated learning their BRCA mutation status. Conclusions. Direct access to BRCA mutation tests, considered a model for high-risk actionable genetic tests of proven clinical utility, provided clear benefits to participants. The unexpected information demonstrated a cascade effect as relatives of newly identified carriers also sought testing and more mutation carriers were identified. Given the absence of evidence for serious emotional distress or inappropriate actions in this subset of mutation-positive customers who agreed to be interviewed for this study, broader screening of Ashkenazi Jewish women for these three BRCA mutations should be considered. PMID:23638402

  6. Assessing the Feasibility of In-Situ Aerobic Cometabolism of Chlorinated Solvents by a Single-Well Push-Pull and Natural Gradient Drift Tests in McClellan AFB, CA

    NASA Astrophysics Data System (ADS)

    Kim, Y.; Istok, J. D.; Semprini, L.

    2001-12-01

    A single-well push-pull test has been developed to evaluate in-situ aerobic cometabolic treatment of chlorinated aliphatic hydrocarbons (CAHs), such as trichloroethylene (TCE) and cis-1,2-dichloroethylene (c-DCE). A series of single-well natural gradient drift and push-pull tests were conducted in two monitoring wells at the McClellan Air Force Base, CA, where aquifer is contaminated mainly with c-DCE and TCE. Transport characteristics of dissolved solutes [bromide (tracer), propane (growth substrate), ethylene, propylene (nontoxic surrogates to probe for CAH transformation activity), DO and nitrate (nutrient)] were evaluated in push-pull transport tests by injecting 200-L of groundwater containing the solutes into the aquifer (Push), providing a rest period of 18 hours (Reaction), and then extracting 400-L of the test solution/groundwater mixtures (Pull). Mass balances showed over 95% of the injected bromide was recovered, and the recoveries of the other solutes were comparable with bromide. The dispersion of all the solutes was similar indicating sorption or other partitioning processes were minimal. These results indicate that bromide could be used as a conservative tracer for biological activity tests and that little loss of the dissolved gaseous substrates occurred prior to biostimulation of the aquifer. A series of biostimulation tests were performed by injecting 500 L-groundwater containing propane (6 mg/L), DO (25 mg/L), nitrate (9 mg/L as N) and bromide (100 mg/L) into the aquifer. Temporal groundwater samples were obtained from the injection well under natural gradient drift conditions. With repeating biostimulation tests the rates of both propane and DO utilization were increased significantly. The results demonstrated that the progress of biostimulation could be assessed by injecting and monitoring under natural gradient drift conditions. Successive push-pull activity tests were performed after biostimulation was achieved using the same procedures as

  7. Filtering and analysis on the random drift of FOG

    NASA Astrophysics Data System (ADS)

    Tian, Yun-Peng; Yang, Xiao-Jun; Guo, Yun-Zeng; Liu, Feng

    2015-10-01

    Fiber optic gyro (FOG) is an optical gyroscope which is based on the Sagnac effect and uses the optical fiber coil as light propagation channel. Gyro drift consists of two components: systemic drift and random drift. Systemic drift can be compensated by testing and calibrating. Random drift changes with time, so it becomes an important indicator to measure the precision of gyroscope, which has a great impact on the inertial navigation system. It can't be compensated by the simple method. Random drift is a main error of fiber optic gyro (FOG). The static output of FOG is a random project and it has more random noise when as the inertial navigation sensor, which will affect the measurement accuracy. It is an efficient method to reduce the random drift and improve the accuracy by modeling and compensation from the output of FOG. According to the characteristic of fiber optic gyro, the random drift model is studied. Using the time series method, the constant component of the random noise original data is extracted. After stationarity and normality tests, a normal random process is acquired. Based on this, the model is established using the recursive least squares, and then the model is applied to the normal Kalman and adaptive Kalman, finally the data is process with the filter. After experimental verification, the noise variance was reduced after filtering, and the effect is obvious.

  8. Drift-Scale Radionuclide Transport

    SciTech Connect

    J. Houseworth

    2004-09-22

    The purpose of this model report is to document the drift scale radionuclide transport model, taking into account the effects of emplacement drifts on flow and transport in the vicinity of the drift, which are not captured in the mountain-scale unsaturated zone (UZ) flow and transport models ''UZ Flow Models and Submodels'' (BSC 2004 [DIRS 169861]), ''Radionuclide Transport Models Under Ambient Conditions'' (BSC 2004 [DIRS 164500]), and ''Particle Tracking Model and Abstraction of Transport Process'' (BSC 2004 [DIRS 170041]). The drift scale radionuclide transport model is intended to be used as an alternative model for comparison with the engineered barrier system (EBS) radionuclide transport model ''EBS Radionuclide Transport Abstraction'' (BSC 2004 [DIRS 169868]). For that purpose, two alternative models have been developed for drift-scale radionuclide transport. One of the alternative models is a dual continuum flow and transport model called the drift shadow model. The effects of variations in the flow field and fracture-matrix interaction in the vicinity of a waste emplacement drift are investigated through sensitivity studies using the drift shadow model (Houseworth et al. 2003 [DIRS 164394]). In this model, the flow is significantly perturbed (reduced) beneath the waste emplacement drifts. However, comparisons of transport in this perturbed flow field with transport in an unperturbed flow field show similar results if the transport is initiated in the rock matrix. This has led to a second alternative model, called the fracture-matrix partitioning model, that focuses on the partitioning of radionuclide transport between the fractures and matrix upon exiting the waste emplacement drift. The fracture-matrix partitioning model computes the partitioning, between fractures and matrix, of diffusive radionuclide transport from the invert (for drifts without seepage) into the rock water. The invert is the structure constructed in a drift to provide the floor of the

  9. Testing the fecundity advantage hypothesis with Sitobion avenae, Rhopalosiphum padi, and Schizaphis graminum (Hemiptera: Aphididae) feeding on ten wheat accessions.

    PubMed

    Hu, Xiang-Shun; Liu, Xiao-Feng; Thieme, Thomas; Zhang, Gai-Sheng; Liu, Tong-Xian; Zhao, Hui-Yan

    2015-01-01

    The fecundity advantage hypothesis suggests that females with a large body size produce more offspring than smaller females. We tested this hypothesis by exploring the correlations between life-history traits of three aphid species feeding on ten wheat accessions at three levels of analysis with respect to the host plant: overall, inter-accession, and intra-accession. We found that fecundity was significantly correlated with mean relative growth rate (MRGR), weight gain, and development time, and that the faster aphid develops the greater body and fecundity, depending on aphid species, wheat accession, and analyses level. Larger aphids of all three species produced more offspring overall; this held true for Sitobion avenae and Schizaphis graminum at the inter-accession level, and for S. avenae, Rhopalosiphum padi, and S. graminum for three, five, and eight accessions respectively at the intra-accession level. Only one correlation, between intrinsic rates of natural increase (rm) and MRGR, was significant for all aphid species at all three analysis levels. A more accurate statement of the fecundity advantage hypothesis is that cereal aphids with greater MRGR generally maintain higher rm on wheat. Our results also provide a method for exploring relationships between individual life-history traits and population dynamics for insects on host plants. PMID:26680508

  10. Testing the fecundity advantage hypothesis with Sitobion avenae, Rhopalosiphum padi, and Schizaphis graminum (Hemiptera: Aphididae) feeding on ten wheat accessions

    PubMed Central

    Hu, Xiang-Shun; Liu, Xiao-Feng; Thieme, Thomas; Zhang, Gai-Sheng; Liu, Tong-Xian; Zhao, Hui-Yan

    2015-01-01

    The fecundity advantage hypothesis suggests that females with a large body size produce more offspring than smaller females. We tested this hypothesis by exploring the correlations between life-history traits of three aphid species feeding on ten wheat accessions at three levels of analysis with respect to the host plant: overall, inter-accession, and intra-accession. We found that fecundity was significantly correlated with mean relative growth rate (MRGR), weight gain, and development time, and that the faster aphid develops the greater body and fecundity, depending on aphid species, wheat accession, and analyses level. Larger aphids of all three species produced more offspring overall; this held true for Sitobion avenae and Schizaphis graminum at the inter-accession level, and for S. avenae, Rhopalosiphum padi, and S. graminum for three, five, and eight accessions respectively at the intra-accession level. Only one correlation, between intrinsic rates of natural increase (rm) and MRGR, was significant for all aphid species at all three analysis levels. A more accurate statement of the fecundity advantage hypothesis is that cereal aphids with greater MRGR generally maintain higher rm on wheat. Our results also provide a method for exploring relationships between individual life-history traits and population dynamics for insects on host plants. PMID:26680508

  11. HIV Risk Behavior and Access to Services: What Predicts HIV Testing among Heterosexually-Active Homeless Men?

    PubMed Central

    Wenzel, Suzanne L.; Rhoades, Harmony; Tucker, Joan S.; Golinelli, Daniela; Kennedy, David P.; Zhou, Annie; Ewing, Brett

    2013-01-01

    Objectives HIV is a serious epidemic among homeless persons, where rates of infection are estimated to be three times higher than in the general population. HIV testing is an effective tool for reducing HIV transmission and for combating poor HIV/AIDS health outcomes that disproportionately affect homeless persons, however, little is known about the HIV testing behavior of homeless men. This study examined the association between individual (HIV risk) and structural (service access) factors and past year HIV testing. Methods Participants were a representative sample of 305 heterosexually active homeless men interviewed from meal programs in the Skid Row region of Los Angeles. Logistic regression examined the association between past year HIV testing and demographic characteristics, HIV risk behavior, and access to other services in the Skid Row area in the past 30 days. Results Despite high rates of past year HIV testing, study participants also reported high rates of HIV risk behavior, suggesting there is still significant unmet need for HIV prevention among homeless men. Having recently used medical/dental services in the Skid Row area (OR: 1.91; CI: 1.09, 3.35), and being a military veteran (OR: 2.10; CI: 1.01 – 4.37) were significantly associated with HIV testing service utilization. Conclusions HIV testing was not associated with HIV risk behavior, but rather with access to services and veteran status, the latter of which prior research has linked to increased service access. Therefore, we suggest that programs encouraging general medical service access may be important for disseminating HIV testing services to this high-risk, vulnerable population. PMID:22676465

  12. Determination of selection criteria for spray drift reduction from atomization data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When testing and evaluating drift reduction technologies (DRT), there are different metrics that can be used to determine if the technology reduces drift as compared to a reference system. These metrics can include reduction in percent of fine drops, measured spray drift from a field trial, or comp...

  13. Drift waves in rotating plasmas

    SciTech Connect

    Horton, W.; Liu, J.

    1983-09-01

    The stability of the electron drift wave is investigated in the presence of E x B plasma rotation typical of the central cell plasma in tandem mirrors. It is shown that a rotationally-driven drift wave may occur at low azimuthal mode numbers. Conditions for rotational instabilities are derived. Quasilinear formulas are given for the anomalous transport associated with the unstable fluctuations.

  14. Toward Accessible Assessments: The Promises and Limitations of Test Item Adaptations for Students with Disabilities and English Language Learners

    ERIC Educational Resources Information Center

    Cawthon, Stephanie; Leppo, Rachel; Carr, Therese; Kopriva, Rebecca

    2013-01-01

    When do item adaptations veer from their intent and, instead of increasing access, modify the construct being measured? This study analyzed early elementary student achievement data from a statewide field test containing both standard and adapted science items. Four student groups were included in this analysis: English language learners, students…

  15. Evaluating School and Parent Reports of the National Student Achievement Testing System (SIMCE) in Chile: Access, Comprehension, and Use

    ERIC Educational Resources Information Center

    Taut, Sandy; Cortes, Flavio; Sebastian, Christian; Preiss, David

    2009-01-01

    This evaluation examined school and parent reports of the national student achievement testing system (SIMCE) in Chile regarding three dimensions: access, comprehension, and use. We conducted phone surveys with a representative sample of directors (N = 375), teachers (N = 1145) and parents (N = 625), and we collected more in-depth data through…

  16. Spinocerebellar Ataxia: Patient and Health Professional Perspectives on Whether and How Patents Affect Access to Clinical Genetic Testing

    PubMed Central

    Powell, Ashton; Chandrasekharan, Subhashini; Cook-Deegan, Robert

    2011-01-01

    Genetic testing for spinocerebellar ataxia (SCA) is used in diagnosis of rare movement disorders. Such testing generally does not affect treatment, but confirmation of mutations in a known gene can confirm diagnosis and end an often years-long quest for the cause of distressing and disabling symptoms. Through interviews and a web forum hosted by the National Ataxia Foundation, patients and health professionals related their experiences with patents’ impact on access to genetic testing for SCA. In the United States, Athena Diagnostics holds either a patent or an exclusive license to a patent in the case of 6 SCA variants (SCA1-3 & 6-8) and two other hereditary ataxias (Friedreich’s Ataxia and Early Onset Ataxia). Athena has enforced its exclusive rights to SCA-related patents by sending cease and desist letters to multiple laboratories offering genetic testing for inherited neurological conditions, including SCA. Roughly half of web forum respondents had decided not to get genetic tests. Price, coverage and reimbursement by insurers and health plans, and fear of genetic discrimination were the main reasons cited for deciding not to get tested. Price was cited as an access concern by the physicians, and as sole US provider, coverage and reimbursement depend on having payment agreements between Athena and payers. In cases where payers do not reimburse, the patient is responsible for payment, although some patients can apply to the voluntary Athena Access and Patient Protection Programs offered by the company. PMID:20393313

  17. Spinocerebellar ataxia: patient and health professional perspectives on whether and how patents affect access to clinical genetic testing.

    PubMed

    Powell, Ashton; Chandrasekharan, Subhashini; Cook-Deegan, Robert

    2010-04-01

    Genetic testing for spinocerebellar ataxia is used in diagnosis of rare movement disorders. Such testing generally does not affect treatment, but confirmation of mutations in a known gene can confirm diagnosis and end an often years-long quest for the cause of distressing and disabling symptoms. Through interviews and a web forum hosted by the National Ataxia Foundation, patients and health professionals related their experiences with the effect of patents on access to genetic testing for spinocerebellar ataxia. In the United States, Athena Diagnostics holds either a patent or an exclusive license to a patent in the case of six spinocerebellar ataxia variants (spinocerebellar ataxia 1-3 and 6-8) and two other hereditary ataxias (Friedreich's Ataxia and Early Onset Ataxia). Athena has enforced its exclusive rights to spinocerebellar ataxia-related patents by sending notification letters to multiple laboratories offering genetic testing for inherited neurological conditions, including spinocerebellar ataxia. Roughly half of web forum respondents had decided not to get genetic tests. Price, coverage and reimbursement by insurers and health plans, and fear of genetic discrimination were the main reasons cited for deciding not to get tested. Price was cited as an access concern by the physicians, and as sole US provider, coverage and reimbursement depend on having payment agreements between Athena and payers. In cases in which payers do not reimburse, the patient is responsible for payment, although some patients can apply to the voluntary Athena Access and Patient Protection Plan offered by the company. PMID:20393313

  18. Drift mode accelerometry for spaceborne gravity measurements

    NASA Astrophysics Data System (ADS)

    Conklin, John W.

    2015-11-01

    A drift mode accelerometer is a precision instrument for spacecraft that overcomes much of the acceleration noise and readout dynamic range limitations of traditional electrostatic accelerometers. It has the potential of achieving acceleration noise performance similar to that of drag-free systems over a restricted frequency band without the need for external drag-free control or continuous spacecraft propulsion. Like traditional accelerometers, the drift mode accelerometer contains a high-density test mass surrounded by an electrode housing, which can control and sense all six degrees of freedom of the test mass. Unlike traditional accelerometers, the suspension system is operated with a low duty cycle so that the limiting suspension force noise only acts over brief, known time intervals, which can be neglected in the data analysis. The readout is performed using a laser interferometer which is immune to the dynamic range limitations of even the best voltage references typically used to determine the inertial acceleration of electrostatic accelerometers. The drift mode accelerometer is a novel offshoot of the like-named operational mode of the LISA Pathfinder spacecraft, in which its test mass suspension system is cycled on and off to estimate the acceleration noise associated with the front-end electronics. This paper presents the concept of a drift mode accelerometer, describes the operation of such a device, develops models for its performance with respect to non-drag-free satellite geodesy and gravitational wave missions, and discusses plans for testing the performance of a prototype sensor in the laboratory using torsion pendula.

  19. Access and Quality of HIV-Related Point-of-Care Diagnostic Testing in Global Health Programs.

    PubMed

    Fonjungo, Peter N; Boeras, Debrah I; Zeh, Clement; Alexander, Heather; Parekh, Bharat S; Nkengasong, John N

    2016-02-01

    Access to point-of-care testing (POCT) improves patient care, especially in resource-limited settings where laboratory infrastructure is poor and the bulk of the population lives in rural settings. However, because of challenges in rolling out the technology and weak quality assurance measures, the promise of human immunodeficiency virus (HIV)-related POCT in resource-limited settings has not been fully exploited to improve patient care and impact public health. Because of these challenges, the Joint United Nations Programme on HIV/AIDS (UNAIDS), in partnership with other organizations, recently launched the Diagnostics Access Initiative. Expanding HIV programs, including the "test and treat" strategies and the newly established UNAIDS 90-90-90 targets, will require increased access to reliable and accurate POCT results. In this review, we examine various components that could improve access and uptake of quality-assured POC tests to ensure coverage and public health impact. These components include evaluation, policy, regulation, and innovative approaches to strengthen the quality of POCT. PMID:26423384

  20. 3-dimensional Oil Drift Simulations

    NASA Astrophysics Data System (ADS)

    Wettre, C.; Reistad, M.; Hjøllo, B.Å.

    Simulation of oil drift has been an ongoing activity at the Norwegian Meteorological Institute since the 1970's. The Marine Forecasting Centre provides a 24-hour service for the Norwegian Pollution Control Authority and the oil companies operating in the Norwegian sector. The response time is 30 minutes. From 2002 the service is extended to simulation of oil drift from oil spills in deep water, using the DeepBlow model developed by SINTEF Applied Chemistry. The oil drift model can be applied both for instantaneous and continuous releases. The changes in the mass of oil and emulsion as a result of evaporation and emulsion are computed. For oil spill at deep water, hydrate formation and gas dissolution are taken into account. The properties of the oil depend on the oil type, and in the present version 64 different types of oil can be simulated. For accurate oil drift simulations it is important to have the best possible data on the atmospheric and oceanic conditions. The oil drift simulations at the Norwegian Meteorological Institute are always based on the most updated data from numerical models of the atmosphere and the ocean. The drift of the surface oil is computed from the vectorial sum of the surface current from the ocean model and the wave induced Stokes drift computed from wave energy spectra from the wave prediction model. In the new model the current distribution with depth is taken into account when calculating the drift of the dispersed oil droplets. Salinity and temperature profiles from the ocean model are needed in the DeepBlow model. The result of the oil drift simulations can be plotted on sea charts used for navigation, either as trajectory plots or particle plots showing the situation at a given time. The results can also be sent as data files to be included in the user's own GIS system.

  1. Drift Mode Accelerometry for Spaceborne Gravity Measurements

    NASA Astrophysics Data System (ADS)

    Conklin, J. W.; Shelley, R.; Chilton, A.; Olatunde, T.; Ciani, G.; Mueller, G.

    2014-12-01

    A drift mode accelerometer is a precision instrument for spacecraft that overcomes much of the acceleration noise and readout dynamic range limitations of traditional electrostatic accelerometers. It has the potential of achieving acceleration noise performance similar to that of drag-free systems over a restricted frequency band without the need for external drag-free control or continuous spacecraft propulsion. Like traditional accelerometers, the drift mode accelerometer contains a high-density test mass surrounded by an electrode housing, which can control and sense all six degrees of freedom of the test mass. Unlike traditional accelerometers, the suspension system is operated with a low duty cycle so that the limiting suspension force noise only acts over brief, known time intervals, which can be accounted for in the data analysis. The readout is performed using a laser interferometer which is immune to the dynamic range limitations of even the best voltage references typically used to determine the inertial acceleration of electrostatic accelerometers. This presentation describes operation and performance modeling for such a device with respect to a low Earth orbiting satellite geodesy mission. Methods for testing the drift mode accelerometer with the University of Florida precision torsion pendulum will also be discussed.

  2. An exploratory study into the effect of time-restricted internet access on face-validity, construct validity and reliability of postgraduate knowledge progress testing

    PubMed Central

    2013-01-01

    Background Yearly formative knowledge testing (also known as progress testing) was shown to have a limited construct-validity and reliability in postgraduate medical education. One way to improve construct-validity and reliability is to improve the authenticity of a test. As easily accessible internet has become inseparably linked to daily clinical practice, we hypothesized that allowing internet access for a limited amount of time during the progress test would improve the perception of authenticity (face-validity) of the test, which would in turn improve the construct-validity and reliability of postgraduate progress testing. Methods Postgraduate trainees taking the yearly knowledge progress test were asked to participate in a study where they could access the internet for 30 minutes at the end of a traditional pen and paper test. Before and after the test they were asked to complete a short questionnaire regarding the face-validity of the test. Results Mean test scores increased significantly for all training years. Trainees indicated that the face-validity of the test improved with internet access and that they would like to continue to have internet access during future testing. Internet access did not improve the construct-validity or reliability of the test. Conclusion Improving the face-validity of postgraduate progress testing, by adding the possibility to search the internet for a limited amount of time, positively influences test performance and face-validity. However, it did not change the reliability or the construct-validity of the test. PMID:24195696

  3. Temperature Induced Voltage Offset Drifts in Silicon Carbide Pressure Sensors

    NASA Technical Reports Server (NTRS)

    Okojie, Robert S.; Lukco, Dorothy; Nguyen, Vu; Savrun, Ender

    2012-01-01

    We report the reduction of transient drifts in the zero pressure offset voltage in silicon carbide (SiC) pressure sensors when operating at 600 C. The previously observed maximum drift of +/- 10 mV of the reference offset voltage at 600 C was reduced to within +/- 5 mV. The offset voltage drifts and bridge resistance changes over time at test temperature are explained in terms of the microstructure and phase changes occurring within the contact metallization, as analyzed by Auger electron spectroscopy and field emission scanning electron microscopy. The results have helped to identify the upper temperature reliable operational limit of this particular metallization scheme to be 605 C.

  4. An Investigation of How the Channel of Input and Access to Test Questions Affect L2 Listening Test Performance

    ERIC Educational Resources Information Center

    Wagner, Elvis

    2013-01-01

    The use of video technology has become widespread in the teaching and testing of second-language (L2) listening, yet research into how this technology affects the learning and testing process has lagged. The current study investigated how the channel of input (audiovisual vs. audio-only) used on an L2 listening test affected test-taker…

  5. A clearing house for diagnostic testing: the solution to ensure access to and use of patented genetic inventions?

    PubMed Central

    van Zimmeren, Esther; Verbeure, Birgit; Matthijs, Gert; Van Overwalle, Geertrui

    2006-01-01

    In genetic diagnostics, the emergence of a so-called "patent thicket" is imminent. Such an overlapping set of patent rights may have restrictive effects on further research and development of diagnostic tests, and the provision of clinical diagnostic services. Currently, two models that may facilitate access to and use of patented genetic inventions are attracting much debate in various national and international fora: patent pools and clearing houses. In this article, we explore the concept of clearing houses. Several types of clearing houses are identified. First, we describe and discuss two types that would provide access to information on the patented inventions: the information clearing house and the technology exchange clearing house. Second, three types of clearing houses are analysed that not only offer access to information but also provide an instrument to facilitate the use of the patented inventions: the open access clearing house, the standardized licences clearing house and the royalty collection clearing house. A royalty collection clearing house for genetic diagnostic testing would be the most comprehensive as it would serve several functions: identifying patents and patent claims essential to diagnostic testing, matching licensees with licensors, developing and supplying standardized licences, collecting royalties, monitoring whether users respect licensing conditions, and providing dispute resolution services such as mediation and arbitration. In this way, it might function as an effective model for users to facilitate access to and use of the patented inventions. However, it remains to be seen whether patent holders with a strong patent portfolio will be convinced by the advantages of the royalty collection clearing house and be willing to participate. PMID:16710543

  6. Time-dependent drift Hamiltonian

    SciTech Connect

    Boozer, A.H.

    1983-03-01

    The lowest-order drift equations are given in a canonical magnetic coordinate form for time-dependent magnetic and electric fields. The advantages of the canonical Hamiltonian form are also discussed.

  7. Classroom Use of Test Accommodations: Issues of Access, Equity, and Conflation

    ERIC Educational Resources Information Center

    Schissel, Jamie L.

    2014-01-01

    Test accommodations are changes to test administration, responses, or the test itself that are offered to emergent bilingual students for standardized tests and also for classroom assessments in some states in the USA. Currently there is a lack of research examining the use of test accommodations as a pedagogical practice. This paper presents a…

  8. Does insecticide drift adversely affect grasshoppers (Orthoptera: Saltatoria) in field margins? A case study combining laboratory acute toxicity testing with field monitoring data.

    PubMed

    Bundschuh, Rebecca; Schmitz, Juliane; Bundschuh, Mirco; Brühl, Carsten Albrecht

    2012-08-01

    The current terrestrial risk assessment of insecticides regarding nontarget arthropods considers exclusively beneficial organisms, whereas herbivorous insects, such as grasshoppers, are ignored. However, grasshoppers living in field margins or meadows adjacent to crops may potentially be exposed to insecticides due to contact with or ingestion of contaminated food. Therefore, the present study assessed effects of five active ingredients of insecticides (dimethoate, pirimicarb, imidacloprid, lambda-cyhalothrin, and deltamethrin) on the survival of Chorthippus sp. grasshopper nymphs by considering two routes of exposure (contact and oral). The experiments were accompanied by monitoring field margins that neighbored cereals, vineyards, and orchards. Grasslands were used as reference sites. The laboratory toxicity tests revealed a sensitivity of grasshoppers with regard to the insecticides tested in the present study similar to that of the standard test species used in arthropod risk assessments. In the field monitoring program, increasing grasshopper densities were detected with increasing field margin width next to cereals and vineyards, but densities remained low over the whole range of field margins from 0.5 to 20 m next to orchards. Grasshopper densities equivalent to those of grassland sites were only observed in field margins exceeding 9 m in width, except for field margins next to orchards. These results may indicate that current insecticide risk assessments are insufficiently protective for grasshoppers in field margins. PMID:22619160

  9. Drift sight replacement in the U-2

    NASA Astrophysics Data System (ADS)

    Bialecki, Lawrence J.

    2005-05-01

    When first deployed in the mid 1950s, the U-2 had an inverted periscope (Drift Sight) to provide the pilot a view of the area below the aircraft. During a recent glass cockpit upgrade, this periscope was removed. This paper discusses: " The development activity leading up to flight test of an Electro Optical Viewsight System (EOVS) replacement for the Drift Sight. The impact and design consideration of using an inexpensive Commercial Off the Shelf (COTS) cameral module, originally designed for small hand held video cameras, " The process used to develop the basic requirements and how early input from the user community lead to an effective design (e.g.., Hand Grip), " The ruggedization techniques necessary to ensure the camera would meet the vibration, thermal, and Electro Magnetic Interface (EMI) environment, " Actual system performance data, " Growth "hooks" and how they were accommodated in a firm fixed price contract.

  10. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1989-03-01

    Twenty-three laced permanent magnet quadrupole drift tube magnets have been constructed, tested, and installed in the SuperHILAC heavy ion linear accelerator at LBL, marking the first accelerator use of this new type of quadrupole. The magnets consist of conventional tape-wound quadrupole electromagnets, using iron pole-pieces, with permanent magnet material (samarium cobalt) inserted between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the individual quadrupole magnets in a drift tube linac is never reversed, we can take advantage of this asymmetrical saturation to provide about 20% greater focusing strength than is available with conventional quadrupoles, while replacing the vanadium permendur poletips with iron poletips. Comparisons between these magnets and conventional tape-wound quadrupoles will be presented. 3 refs., 5 figs.

  11. GENERIC VERIFICATION PROTOCOL FOR THE VERIFICATION OF PESTICIDE SPRAY DRIFT REDUCTION TECHNOLOGIES FOR ROW AND FIELD CROPS

    EPA Science Inventory

    This ETV program generic verification protocol was prepared and reviewed for the Verification of Pesticide Drift Reduction Technologies project. The protocol provides a detailed methodology for conducting and reporting results from a verification test of pesticide drift reductio...

  12. Drift analysis for integer IDCT

    NASA Astrophysics Data System (ADS)

    Hinds, Arianne T.; Reznik, Yuriy A.; Yu, Lu; Ni, Zhibo; Zhang, Cixun

    2007-09-01

    This paper analyzes the drift phenomenon that occurs between video encoders and decoders that employ different implementations of the Inverse Discrete Cosine Transform (IDCT). Our methodology utilizes MPEG-2, MPEG-4 Part 2, and H.263 encoders and decoders to measure drift occurring at low QP values for CIF resolution video sequences. Our analysis is conducted as part of the effort to define specific implementations for the emerging ISO/IEC 23002-2 Fixed-Point 8x8 IDCT and DCT standard. Various IDCT implementations submitted as proposals for the new standard are used to analyze drift. Each of these implementations complies with both the IEEE Standard 1180 and the new MPEG IDCT precision specification ISO/IEC 23002-1. Reference implementations of the IDCT/DCT, and implementations from well-known video encoders/decoders are also employed. Our results indicate that drift is eliminated entirely only when the implementations of the IDCT in both the encoder and decoder match exactly. In this case, the precision of the IDCT has no influence on drift. In cases where the implementations are not identical, then the use of a highly precise IDCT in the decoder will reduce drift in the reconstructed video sequence only to the extent that the IDCT used in the encoder is also precise.

  13. Beyond the Test Score: A Mixed Methods Analysis of a College Access Intervention in Chile

    ERIC Educational Resources Information Center

    Treviño, Ernesto; Scheele, Judith; Flores, Stella M.

    2014-01-01

    Using both quantitative and qualitative analyses, we examine the role of a college access intervention in the enrollment and persistence outcomes of low-income students in Chile modeled partially after a Texas admissions program. We find that, although students from the program have a mean cumulative GPA significantly lower than that of their…

  14. Testing an Asset-Building Approach for Young People: Early Access to Savings Predicts Later Savings

    ERIC Educational Resources Information Center

    Friedline, Terri; Elliott, William; Chowa, Gina A. N.

    2013-01-01

    A major hypothesis of asset-building is that early access to savings accounts leads to continued and improved educational and economic outcomes over time. This study asks whether or not young adults (ages 18-22) in 2007, particularly among lower income households, are significantly more likely to own savings accounts and to accumulate more savings…

  15. Design and testing of access-tube TDR soil water sensor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We developed the design of a waveguide on the exterior of an access tube for use in time-domain reflectometry (TDR) for in-situ soil water content sensing. In order to optimize the design with respect to sampling volume and losses, we derived the electromagnetic (EM) fields produced by a TDR sensor...

  16. Drift-Scale THC Seepage Model

    SciTech Connect

    C.R. Bryan

    2005-02-17

    The purpose of this report (REV04) is to document the thermal-hydrologic-chemical (THC) seepage model, which simulates the composition of waters that could potentially seep into emplacement drifts, and the composition of the gas phase. The THC seepage model is processed and abstracted for use in the total system performance assessment (TSPA) for the license application (LA). This report has been developed in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2005 [DIRS 172761]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this report. The plan for validation of the models documented in this report is given in Section 2.2.2, ''Model Validation for the DS THC Seepage Model,'' of the TWP. The TWP (Section 3.2.2) identifies Acceptance Criteria 1 to 4 for ''Quantity and Chemistry of Water Contacting Engineered Barriers and Waste Forms'' (NRC 2003 [DIRS 163274]) as being applicable to this report; however, in variance to the TWP, Acceptance Criterion 5 has also been determined to be applicable, and is addressed, along with the other Acceptance Criteria, in Section 4.2 of this report. Also, three FEPS not listed in the TWP (2.2.10.01.0A, 2.2.10.06.0A, and 2.2.11.02.0A) are partially addressed in this report, and have been added to the list of excluded FEPS in Table 6.1-2. This report has been developed in accordance with LP-SIII.10Q-BSC, ''Models''. This report documents the THC seepage model and a derivative used for validation, the Drift Scale Test (DST) THC submodel. The THC seepage model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral alteration on flow in rocks surrounding drifts. The DST THC submodel uses a drift

  17. Access to syringes for HIV prevention for injection drug users in St. Petersburg, Russia: syringe purchase test study

    PubMed Central

    2013-01-01

    Background The HIV epidemic in Russia is concentrated among injection drug users (IDUs). This is especially true for St. Petersburg where high HIV incidence persists among the city’s estimated 80,000 IDUs. Although sterile syringes are legally available, access for IDUs may be hampered. To explore the feasibility of using pharmacies to expand syringe access and provide other prevention services to IDUs, we investigated the current access to sterile syringes at the pharmacies and the correlation between pharmacy density and HIV prevalence in St. Petersburg. Methods 965 pharmacies citywide were mapped, classified by ownership type, and the association between pharmacy density and HIV prevalence at the district level was tested. We selected two districts among the 18 districts – one central and one peripheral – that represented two major types of city districts and contacted all operating pharmacies by phone to inquire if they stocked syringes and obtained details about their stock. Qualitative interviews with 26 IDUs provided data regarding syringe access in pharmacies and were used to formulate hypotheses for the pharmacy syringe purchase test wherein research staff attempted to purchase syringes in all pharmacies in the two districts. Results No correlation was found between the density of pharmacies and HIV prevalence at the district level. Of 108 operating pharmacies, 38 (35%) did not sell syringes of the types used by IDUs; of these, half stocked but refused to sell syringes to research staff, and the other half did not stock syringes at all. Overall 70 (65%) of the pharmacies did sell syringes; of these, 49 pharmacies sold single syringes without any restrictions and 21 offered packages of ten. Conclusions Trainings for pharmacists need to be conducted to reduce negative attitudes towards IDUs and increase pharmacists’ willingness to sell syringes. At a structural level, access to safe injection supplies for IDUs could be increased by including syringes

  18. Ocean modelling aspects for drift applications

    NASA Astrophysics Data System (ADS)

    Stephane, L.; Pierre, D.

    2010-12-01

    Nowadays, many authorities in charge of rescue-at-sea operations lean on operational oceanography products to outline research perimeters. Moreover, current fields estimated with sophisticated ocean forecasting systems can be used as input data for oil spill/ adrift object fate models. This emphasises the necessity of an accurate sea state forecast, with a mastered level of reliability. This work focuses on several problems inherent to drift modeling, dealing in the first place with the efficiency of the oceanic current field representation. As we want to discriminate the relevance of a particular physical process or modeling option, the idea is to generate series of current fields of different characteristics and then qualify them in term of drift prediction efficiency. Benchmarked drift scenarios were set up from real surface drifters data, collected in the Mediterranean sea and off the coasts of Angola. The time and space scales that we are interested in are about 72 hr forecasts (typical timescale communicated in case of crisis), for distance errors that we hope about a few dozen of km around the forecast (acceptable for reconnaissance by aircrafts) For the ocean prediction, we used some regional oceanic configurations based on the NEMO 2.3 code, nested into Mercator 1/12° operational system. Drift forecasts were computed offline with Mothy (Météo France oil spill modeling system) and Ariane (B. Blanke, 1997), a Lagrangian diagnostic tool. We were particularly interested in the importance of the horizontal resolution, vertical mixing schemes, and any processes that may impact the surface layer. The aim of the study is to ultimately point at the most suitable set of parameters for drift forecast use inside operational oceanic systems. We are also motivated in assessing the relevancy of ensemble forecasts regarding determinist predictions. Several tests showed that mis-described observed trajectories can finally be modelled statistically by using uncertainties

  19. Inoculation against Forgetting: Advantages of Immediate versus Delayed Initial Testing Due to Superior Verbatim Accessibility

    ERIC Educational Resources Information Center

    Pansky, Ainat

    2012-01-01

    In this study, potential benefits of early memory testing were examined in terms of "inoculating" eyewitness memory against forgetting. As predicted by fuzzy trace theory (e.g., Reyna & Titcomb, 1997), a larger testing advantage in the delayed recall of event details was expected after immediate testing than after delayed testing because of the…

  20. The Drifting Star

    NASA Astrophysics Data System (ADS)

    2008-04-01

    By studying in great detail the 'ringing' of a planet-harbouring star, a team of astronomers using ESO's 3.6-m telescope have shown that it must have drifted away from the metal-rich Hyades cluster. This discovery has implications for theories of star and planet formation, and for the dynamics of our Milky Way. ESO PR Photo 09a/08 ESO PR Photo 09a/08 Iota Horologii The yellow-orange star Iota Horologii, located 56 light-years away towards the southern Horologium ("The Clock") constellation, belongs to the so-called "Hyades stream", a large number of stars that move in the same direction. Previously, astronomers using an ESO telescope had shown that the star harbours a planet, more than 2 times as large as Jupiter and orbiting in 320 days (ESO 12/99). But until now, all studies were unable to pinpoint the exact characteristics of the star, and hence to understand its origin. A team of astronomers, led by Sylvie Vauclair from the University of Toulouse, France, therefore decided to use the technique of 'asteroseismology' to unlock the star's secrets. "In the same way as geologists monitor how seismic waves generated by earthquakes propagate through the Earth and learn about the inner structure of our planet, it is possible to study sound waves running through a star, which forms a sort of large, spherical bell," says Vauclair. The 'ringing' from this giant musical instrument provides astronomers with plenty of information about the physical conditions in the star's interior. And to 'listen to the music', the astronomers used one of the best instruments available. The observations were conducted in November 2006 during 8 consecutive nights with the state-of-the-art HARPS spectrograph mounted on the ESO 3.6-m telescope at La Silla. Up to 25 'notes' could be identified in the unique dataset, most of them corresponding to waves having a period of about 6.5 minutes. These observations allowed the astronomers to obtain a very precise portrait of Iota Horologii: its

  1. The Electron Drift Technique for Measuring Electric and Magnetic Fields

    NASA Technical Reports Server (NTRS)

    Paschmann, G.; McIlwain, C. E.; Quinn, J. M.; Torbert, R. B.; Whipple, E. C.; Christensen, John (Technical Monitor)

    1998-01-01

    The electron drift technique is based on sensing the drift of a weak beam of test electrons that is caused by electric fields and/or gradients in the magnetic field. These quantities can, by use of different electron energies, in principle be determined separately. Depending on the ratio of drift speed to magnetic field strength, the drift velocity can be determined either from the two emission directions that cause the electrons to gyrate back to detectors placed some distance from the emitting guns, or from measurements of the time of flight of the electrons. As a by-product of the time-of-flight measurements, the magnetic field strength is also determined. The paper describes strengths and weaknesses of the method as well as technical constraints.

  2. Drift distance survey in DPIS for high current beam production

    SciTech Connect

    Kanesue,T.; Okamura, M.; Kondo, K.; Tamura, J.; Kashiwagi, H.; Zhang, Z.

    2009-09-20

    In a laser ion source, plasma drift distance is one of the most important design parameters. Ion current density and beam pulse width are defined by plasma drift distance between laser target and beam extraction position. In direct plasma injection scheme (DPIS), which uses a laser ion source and Radio Frequency Quadrupole (RFQ) linac, we can apply relatively higher electric field at the beam extraction due to the unique shape of a positively biased electrode. However, when we aim at very high current acceleration like several tens of mA, we observed mismatched beam extraction conditions. We tested three different ion current at ion extraction region by changing plasma drift distance to study better extraction condition. In this experiment, C{sup 6+} beam was accelerated. We confirmed that the matching condition can be improved by controlling plasma drift distance.

  3. A drift chamber telescope for high-Z particles

    SciTech Connect

    Isbert, J. |; Crawford, H.J.; Mathis, K.D.; Guzik, T.G.; Mitchell, J.W.; Wefel, J.P.; Hof, M.; Neuhaus, J.; Simon, M.

    1990-02-01

    Drift chambers are one of the position sensing technologies used in cosmic ray balloon and satellite experiments with potential application to the next generation of detectors for space flight. A low mass TPC type drift chamber, employing 8 distinct drift regions within a single gas volume has been built, tested and used at the LBL Bevalac. From the drift time X-coordinate, spatial resolutions below 100 {mu}m are obtained for a variety of heavy ions with selected trigger modes. The Y-coordinate is determined by pickup pads located behind the anode wire, thereby providing both X and Y coordinates from the same avalanche. Results from different timing schemes, {delta}-ray effects and the pickup pad resolution are presented. 6 refs., 5 figs.

  4. Genetic drift and the population history of the Irish travellers.

    PubMed

    Relethford, John H; Crawford, Michael H

    2013-02-01

    The Irish Travellers are an itinerant group in Ireland that has been socially isolated. Two hypotheses have been proposed concerning the genetic origin of the Travellers: (1) they are genetically related to Roma populations in Europe that share a nomadic lifestyle or (2) they are of Irish origin, and genetic differences from the rest of Ireland reflect genetic drift. These hypotheses were tested using data on 33 alleles from 12 red blood cell polymorphism loci. Comparison with other European, Roma, and Indian populations shows that the Travellers are genetically distinct from the Roma and Indian populations and most genetically similar to Ireland, in agreement with earlier genetic analyses of the Travellers. However, the Travellers are still genetically distinct from other Irish populations, which could reflect some external gene flow and/or the action of genetic drift in a small group that was descended from a small number of founders. In order to test the drift hypothesis, we analyzed genetic distances comparing the Travellers to four geographic regions in Ireland. These distances were then compared with adjusted distances that account for differential genetic drift using a method developed by Relethford (Hum Biol 68 (1996) 29-44). The unadjusted distances show the genetic distinctiveness of the Travellers. After adjustment for the expected effects of genetic drift, the Travellers are equidistant from the other Irish samples, showing their Irish origins and population history. The observed genetic differences are thus a reflection of genetic drift, and there is no evidence of any external gene flow. PMID:23180293

  5. Atlas of Dutch drift sands

    NASA Astrophysics Data System (ADS)

    Riksen, Michel; Jungerius, Pieter

    2013-04-01

    The Netherlands is well known for its aeolian landscapes. Frequent storms during the High Middle Ages (1000-1300 AD) reactivated Pleistocene coversands and river dunes and are responsible for the formation of the Holocene drift sands at a scale which is unique for Europe. A hypothesized relationship with farmer practices for making plaggensoils has recently been refuted, because drift sand formation began centuries earlier. The coastal dune belt with their parabolic dunes dates from the same period as the drift sand. An estimate of the extent of drift sands can be made from soil maps: drift sands are too young to show much profile development (Regosols). With this method Koster estimated the maximum extent of Holocene drift sands in the Netherlands to be about 800 km2 (Koster 2005). Laser altimetry allows a more precise estimate of the total surface affected by wind from the characteristic relief patterns produced by the Holocene wind, which is different from the smooth surface of cover sand deposits. Laser altimetry has been used before to investigate the mechanism of drift sand formation (Jungerius & Riksen 2010). Most of the surface affected by wind is not active anymore, but the tell-tale rough surface survived ages of different landuse. The total affected surface amounts to 825 km2. It is noteworthy that both methods give comparable results. We recorded a total number of 367 of affected areas of varying shapes, ranging in size from 1.6 ha to a large complex of drif sands of 7,119.5 ha. As is to be expected from their mode of origin, most occurrences are associated with cover sands, and with river dunes along the river Meuse and smaller rivers in other parts of the country. Particularly the final phases of cover sand and river dunes that show more relief as parabolic dunes were affected. There are also small aeolian deposits at the lee side blown from fallow agricultural fields but they are (sub)recent. Most of the relief is irregular, but the larger

  6. In-Drift Microbial Communities

    SciTech Connect

    D. Jolley

    2000-11-09

    As directed by written work direction (CRWMS M and O 1999f), Performance Assessment (PA) developed a model for microbial communities in the engineered barrier system (EBS) as documented here. The purpose of this model is to assist Performance Assessment and its Engineered Barrier Performance Section in modeling the geochemical environment within a potential repository drift for TSPA-SR/LA, thus allowing PA to provide a more detailed and complete near-field geochemical model and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near Field Environment (NFE) Revision 2 (NRC 1999). This model and its predecessor (the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document, CRWMS M and O 1998a) was developed to respond to the applicable KTIs. Additionally, because of the previous development of the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document (CRWMS M and O 1998a), the M and O was effectively able to resolve a previous KTI concern regarding the effects of microbial processes on seepage and flow (NRC 1998). This document supercedes the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document (CRWMS M and O 1998a). This document provides the conceptual framework of the revised in-drift microbial communities model to be used in subsequent performance assessment (PA) analyses.

  7. SAA drift:experimental results

    NASA Astrophysics Data System (ADS)

    Grigoryan, O. R.; Kudela, K.; Romashova, V. V.; Drozdov, A. Yu.

    According to the paleomagnetic analysis there are variations of Earth's magnetic field connected with magnetic momentum changing. Besides these variations affects on the trapped belt South Atlantic Anomaly (SAA) location. Indeed different observations including Space Shuttle short-time flights approved the existence SAA westward drift with speed 0.1-1.0 (deg/year) and northward drift with speed approximately 0.1 (deg/year). In this work we present the analysis of experimental results obtained in SINP MSU in 1972-2003 from different satellites. There were analyzed the fluxes of protons with energy > 50 MeV, gamma quanta with energy > 500 keV and neutrons with energy 0.1-1.0 MeV in SAA area and their maxima location. The data about fluxes were obtained onboard the orbital stations ``Salut-6'' (1979), MIR (1991, 1998) and ISS (2003) by the identical experimental equipment. The comparison of the data obtained during these two decades of investigations confirms the fact of the SAA westward drift. Moreover the same analysis of maximum flux location of electrons with hundreds keV energy (satellites ``Kosmos-484'' (1972), ``Interkosmos-17'' (1977) and ``Activny'' (``Interkosmos-24'', 1991)) confirmed not only the SAA westward drift but northward drift also.

  8. Impact of Gene Patents and Licensing Practices on Access to Genetic Testing for Hearing Loss

    PubMed Central

    Chandrasekharan, Subhashini; Fiffer, Melissa

    2011-01-01

    Genetic testing for heritable hearing loss involves a mix of patented and unpatented genes, mutations and testing methods. More than half of all hearing loss is linked to inherited mutations, and five genes are most commonly tested in the United States. There are no patents on three of these genes, but Athena Diagnostics holds exclusive licenses to test for a common mutation in the GJB2 gene associated with about 50% of all cases, as well as mutations in the MTRNR1 gene. This fragmented intellectual property landscape made hearing loss a useful case study for assessing whether patent rights in genetic testing can proliferate or overlap, and whether it is possible to gather the rights necessary to perform testing. Testing for hearing loss is widely available, primarily from academic medical centers. Based on literature reviews and interviews with researchers, research on the genetics of hearing loss has generally not been impeded by patents. There is no consistent evidence of a premium in testing prices attributable to patent status. Athena Diagnostics has, however, used its intellectual property to discourage other providers from offering some tests. There is no definitive answer about the suitability of current patenting and licensing of commonly tested genes because of continuing legal uncertainty about the extent of enforcement of patent rights. Clinicians have also expressed concerns that multiplex tests will be difficult to develop because of overlapping intellectual property and conflict with Athena’s sole provider business model. PMID:20393307

  9. Can the HIV Home Test Promote Access to Care? Lessons Learned from the In-home Pregnancy Test

    PubMed Central

    Schnall, Rebecca; Carballo-Dieguez, Alex; Larson, Elaine

    2015-01-01

    Adolescents and young adults are the fastest growing age group of HIV+ individuals in the US and many who are infected do not know their HIV status. The HIV home test has the potential to help curb the HIV epidemic by improving detection of persons living with HIV and enabling them to seek follow-up care, but, it has not yet been evaluated in adolescents. Analogous to the home pregnancy test, which was met with much resistance and only successfully marketed during a time of social change, the HIV home test has been met with resistance since its FDA approval. This commentary summarizes the need to systematically evaluate positive and untoward/unanticipated effects of HIV home testing, particularly in young adults. PMID:24849622

  10. The CLAS drift chamber system

    SciTech Connect

    Mestayer, M.D.; Carman, D.S.; Asavaphibhop, B.

    1999-04-01

    Experimental Hall B at Jefferson Laboratory houses the CEBAF Large Acceptance Spectrometer, the magnetic field of which is produced by a superconducting toroid. The six coils of this toroid divide the detector azimuthally into six sectors, each of which contains three large multi-layer drift chambers for tracking charged particles produced from a fixed target on a toroidal axis. Within the 18 drift chambers are a total of 35,148 individually instrumented hexagonal drift cells. The novel geometry of these chambers provides for good tracking resolution and efficiency, along with large acceptance. The design and construction challenges posed by these large-scale detectors are described, and detailed results are presented from in-beam measurements.

  11. The continental drift convection cell

    NASA Astrophysics Data System (ADS)

    Whitehead, J. A.; Behn, Mark D.

    2015-06-01

    Continents on Earth periodically assemble to form supercontinents and then break up again into smaller continental blocks (the Wilson cycle). Previous highly developed numerical models incorporate fixed continents while others indicate that continent movement modulates flow. Our simplified numerical model suggests that continental drift is fundamental. A thermally insulating continent is anchored at its center to mantle flow on an otherwise stress-free surface for infinite Prandtl number cellular convection with constant material properties. Rayleigh numbers exceed 107, while continent widths and chamber lengths approach Earth's values. The Wilson cycle is reproduced by a unique, rugged monopolar "continental drift convection cell." Subduction occurs at the cell's upstream end with cold slabs dipping at an angle beneath the moving continent (as found in many continent/subduction regions on Earth). Drift enhances vertical heat transport up to 30%, especially at the core-mantle boundary, and greatly decreases lateral mantle temperature differences.

  12. Redshift drift exploration for interacting dark energy

    NASA Astrophysics Data System (ADS)

    Geng, Jia-Jia; Li, Yun-He; Zhang, Jing-Fei; Zhang, Xin

    2015-08-01

    By detecting redshift drift in the spectra of the Lyman- forest of distant quasars, the Sandage-Loeb (SL) test directly measures the expansion of the universe, covering the "redshift desert" of . Thus this method is definitely an important supplement to the other geometric measurements and will play a crucial role in cosmological constraints. In this paper, we quantify the ability of the SL test signal by a CODEX-like spectrograph for constraining interacting dark energy. Four typical interacting dark energy models are considered: (i) , (ii) , (iii) , and (iv) . The results show that for all the considered interacting dark energy models, relative to the current joint SN BAO CMB observations, the constraints on and would be improved by about 60 and 30-40 %, while the constraints on w and would be slightly improved, with a 30-year observation of the SL test. We also explore the impact of the SL test on future joint geometric observations. In this analysis, we take the model with as an example, and we simulate future SN and BAO data based on the space-based project WFIRST. We find that with the future geometric constraints, the redshift drift observations would help break the geometric degeneracies in a meaningful way, thus the measurement precisions of , , w, and could be substantially improved using future probes.

  13. Access to Adequate Healthcare for Hmong Women: A Patient Navigation Program to Increase Pap Test Screening

    PubMed Central

    Lo, Penny; Fang, Dao Moua; Ly, May Ying; Stewart, Susan; Lee, Serge; Chen, Moon S.

    2015-01-01

    This paper describes the development and implementation of a Hmong Cervical Cancer Intervention Program utilizing a patient navigation model to raise cervical cancer awareness for Hmong women through educational workshops and to assist Hmong women in obtaining a Pap test. Out of 402 women who participated in a baseline survey, the Patient Navigation Program was able to enroll 109 participants who had not had a Pap test in the past 3 years and had never had a Pap test. Through utilization of outreach, an awareness campaign and patient navigation support, at least 38 percent of 109 participants obtained a Pap test. Overall, 21 workshops and 43 outreach activities were conducted by the Hmong Women’s Heritage Association, leading to 63 percent of those enrolled in the Patient Navigation Program who could be contacted to obtain a Pap test. PMID:26594134

  14. An Alcohol Test for Drifting Constants

    NASA Astrophysics Data System (ADS)

    Jansen, P.; Bagdonaite, J.; Ubachs, W.; Bethlem, H. L.; Kleiner, I.; Xu, L.-H.

    2013-06-01

    The Standard Model of physics is built on the fundamental constants of nature, however without providing an explanation for their values, nor requiring their constancy over space and time. Molecular spectroscopy can address this issue. Recently, we found that microwave transitions in methanol are extremely sensitive to a variation of the proton-to-electron mass ratio μ, due to a fortuitous interplay between classically forbidden internal rotation and rotation of the molecule as a whole. In this talk, we will explain the origin of this effect and how the sensitivity coefficients in methanol are calculated. In addition, we set a limit on a possible cosmological variation of μ by comparing transitions in methanol observed in the early Universe with those measured in the laboratory. Based on radio-astronomical observations of PKS1830-211, we deduce a constraint of Δμ/μ=(0.0± 1.0)× 10^{-7} at redshift z = 0.89, corresponding to a look-back time of 7 billion years. While this limit is more constraining and systematically more robust than previous ones, the methanol method opens a new search territory for probing μ-variation on cosmological timescales. P. Jansen, L.-H. Xu, I. Kleiner, W. Ubachs, and H.L. Bethlem Phys. Rev. Lett. {106}(100801) 2011. J. Bagdonaite, P. Jansen, C. Henkel, H.L. Bethlem, K.M. Menten, and W. Ubachs Science {339}(46) 2013.

  15. The development of an optically accessible, high-power combustion test rig.

    PubMed

    Slabaugh, Carson D; Pratt, Andrew C; Lucht, Robert P; Meyer, Scott E; Benjamin, Michael; Lyle, Kent; Kelsey, Mark

    2014-03-01

    This work summarizes the development of a gas turbine combustion experiment which will allow advanced optical measurements to be made at realistic engine conditions. Facility requirements are addressed, including instrumentation and control needs for remote operation when working with high energy flows. The methodology employed in the design of the optically accessible combustion chamber is elucidated, including window considerations and thermal management of the experimental hardware under extremely high heat loads. Experimental uncertainties are also quantified. The stable operation of the experiment is validated using multiple techniques and the boundary conditions are verified. The successful prediction of operating conditions by the design analysis is documented and preliminary data are shown to demonstrate the capability of the experiment to produce high-fidelity datasets for advanced combustion research. PMID:24689618

  16. Measurement of Spray Drift with a Specifically Designed Lidar System.

    PubMed

    Gregorio, Eduard; Torrent, Xavier; Planas de Martí, Santiago; Solanelles, Francesc; Sanz, Ricardo; Rocadenbosch, Francesc; Masip, Joan; Ribes-Dasi, Manel; Rosell-Polo, Joan R

    2016-01-01

    Field measurements of spray drift are usually carried out by passive collectors and tracers. However, these methods are labour- and time-intensive and only provide point- and time-integrated measurements. Unlike these methods, the light detection and ranging (lidar) technique allows real-time measurements, obtaining information with temporal and spatial resolution. Recently, the authors have developed the first eye-safe lidar system specifically designed for spray drift monitoring. This prototype is based on a 1534 nm erbium-doped glass laser and an 80 mm diameter telescope, has scanning capability, and is easily transportable. This paper presents the results of the first experimental campaign carried out with this instrument. High coefficients of determination (R² > 0.85) were observed by comparing lidar measurements of the spray drift with those obtained by horizontal collectors. Furthermore, the lidar system allowed an assessment of the drift reduction potential (DRP) when comparing low-drift nozzles with standard ones, resulting in a DRP of 57% (preliminary result) for the tested nozzles. The lidar system was also used for monitoring the evolution of the spray flux over the canopy and to generate 2-D images of these plumes. The developed instrument is an advantageous alternative to passive collectors and opens the possibility of new methods for field measurement of spray drift. PMID:27070613

  17. Measurement of Spray Drift with a Specifically Designed Lidar System

    PubMed Central

    Gregorio, Eduard; Torrent, Xavier; Planas de Martí, Santiago; Solanelles, Francesc; Sanz, Ricardo; Rocadenbosch, Francesc; Masip, Joan; Ribes-Dasi, Manel; Rosell-Polo, Joan R.

    2016-01-01

    Field measurements of spray drift are usually carried out by passive collectors and tracers. However, these methods are labour- and time-intensive and only provide point- and time-integrated measurements. Unlike these methods, the light detection and ranging (lidar) technique allows real-time measurements, obtaining information with temporal and spatial resolution. Recently, the authors have developed the first eye-safe lidar system specifically designed for spray drift monitoring. This prototype is based on a 1534 nm erbium-doped glass laser and an 80 mm diameter telescope, has scanning capability, and is easily transportable. This paper presents the results of the first experimental campaign carried out with this instrument. High coefficients of determination (R2 > 0.85) were observed by comparing lidar measurements of the spray drift with those obtained by horizontal collectors. Furthermore, the lidar system allowed an assessment of the drift reduction potential (DRP) when comparing low-drift nozzles with standard ones, resulting in a DRP of 57% (preliminary result) for the tested nozzles. The lidar system was also used for monitoring the evolution of the spray flux over the canopy and to generate 2-D images of these plumes. The developed instrument is an advantageous alternative to passive collectors and opens the possibility of new methods for field measurement of spray drift. PMID:27070613

  18. Impact of Gene Patents and Licensing Practices on Access to Genetic Testing for Long QT Syndrome

    PubMed Central

    Angrist, Misha; Chandrasekharan, Subhashini; Heaney, Christopher; Cook-Deegan, Robert

    2010-01-01

    Genetic testing for Long QT syndrome (LQTS) exemplifies patenting and exclusive licensing with different outcomes at different times. Exclusive licensing from the University of Utah changed the business model from sole provider to two US providers of LQTS testing. LQTS is associated with mutations in many genes, ten of which are now tested by two competing firms in the United States, PGxHealth and GeneDx. Until 2009, PGxHealth was sole provider, based largely on exclusive rights to patents from the University of Utah and other academic institutions. University of Utah patents were initially licensed to DNA Sciences, whose patent rights were acquired by Gennaissance, and then by Clinical Data, Inc., which owns PGxHealth. In 2002, DNA Sciences “cleared the market” by sending cease and desist patent enforcement letters to university and reference laboratories offering LQTS genetic testing. There was no test on the market for a one- to two-year period. From 2005-2008, most LQTS-related patents were controlled by Clinical Data, Inc., and its subsidiary PGxHealth. BioReference Laboratories, Inc., secured countervailing exclusive patent rights starting in 2006, also from the University of Utah, and broke the PGxHealth monopoly in early 2009, creating a duopoly for genetic testing in the United States, and expanding the number of genes for which commercial testing is available from five to ten. PMID:20393304

  19. Widening the Access to HIV Testing: The Contribution of Three In-Pharmacy Testing Programmes in Spain

    PubMed Central

    Fernández-Balbuena, Sonia; Belza, María José; Zulaica, Daniel; Martinez, Jose Luis; Marcos, Henar; Rifá, Benet; Arrillaga, Arantxa; de la Fuente, Luis; Hoyos, Juan

    2015-01-01

    Background and Objective Spain has implemented several in-pharmacy HIV testing programmes performed by pharmacists as part of their everyday routine. We aim to assess the feasibility and the main outcomes of three programmes implemented in three Spanish regions with different sociological profiles and also different epidemiology for HIV. Methods The characteristics of the 24151 people tested between 2009 and 2013 at 74 urban pharmacies are studied. We compare the main outcomes of the programmes with those of each Regional HIV Surveillance System (RHSS) assessing the contribution to the total new diagnosis in each region and if priority groups are being reached. Results 45.7% were heterosexual men (MSW), 14.4% men who have sex with men (MSM), and 27% women. The 35% were younger than 30 and 9.6% foreigners. The 52% were previously untested, and women were the most likely to be untested. The three programmes altogether diagnosed 226 people, resulting in a global prevalence of 0.9% (95%CI: 0.8–1.1); 3.4% in MSM (95%CI: 2.8–4.0). The prevalence among Spaniards was 0.8% (0.7–1.0) vs. 2.2 (1.6–2.9) among foreigners. The percentages of MSM diagnosed by all three programmes were higher than the one reported by their respective RHSS. Thirty four percent of the reactive MSM and the 71.4% of the reactive MSW did not have a previous HIV test although big testing history differences were observed across the programmes. Altogether, these services contributed with the 10.6% of all HIV diagnoses in these regions. Conclusions In-pharmacy HIV testing programmes are a valuable testing option, having been able to uncover 1 out of 10 the new diagnoses reported in each region. They showed a good capacity of reaching and diagnosing previously untested populations, not only a priority population such as MSM but also heterosexual population who are more affected by delayed diagnosis. They seem to be particularly suitable for regions without large cities and specific HIV diagnostic

  20. Drift Hamiltonian in magnetic coordinates

    SciTech Connect

    White, R.B.; Boozer, A.H.; Hay, R.

    1982-02-01

    A Hamiltonian formulation of the guiding-center drift in arbitrary, steady state, magnetic and electric fields is given. The canonical variables of this formulation are simply related to the magnetic coordinates. The modifications required to treat ergodic magnetic fields using magnetic coordinates are explicitly given in the Hamiltonian formulation.

  1. Does the geoid drift west?

    NASA Technical Reports Server (NTRS)

    Backus, G. E.; Parker, R. L.; Zumberge, M. A.

    1985-01-01

    In 1970 Hide and Malin noted a correlation of about 0.8 between the geoid and the geomagnetic potential at the Earth's surface when the latter is rotated eastward in longitude by about 160 degrees and the spherical harmonic expansions of both functions are truncated at degree 4. From a century of magnetic observatory data, Hide and Malin inferred an average magnetic westward drift rate of about 0.27 degrees/year. They attributed the magnetic-gravitational correlation to a core event at about 1350 A.D. which impressed the mantle's gravity pattern at long wavelengths onto the core motion and the resulting magnetic field. The impressed pattern was then carried westward 160 degrees by the nsuing magnetic westward drift. An alternative possibility is some sort of steady physical coupling between the magnetic and gravitational fields (perhaps migration of Hide's bumps on the core-mantle interface). This model predicts that the geoid will drift west at the magnetic rate. On a rigid earth, the resulting changes in sea level would be easily observed, but they could be masked by adjustment of the mantle if it has a shell with viscosity considerably less than 10 to the 21 poise. However, steady westward drift of the geoid also predicts secular changes in g, the local acceleration of gravity, at land stations. These changes are now ruled out by recent independent high-accuracy absolute measurements of g made by several workers at various locations in the Northern Hemisphere.

  2. Forecast of iceberg ensemble drift

    SciTech Connect

    El-Tahan, M.S.; El-Tahan, H.W.; Venkatesh, S.

    1983-05-01

    The objectives of the study are to gain a better understanding of the characteristics of iceberg motion and the factors controlling iceberg drift, and to develop an iceberg ensemble drift forecast system to be operated by the Canadian Atmospheric Environment Service. An extensive review of field and theoretical studies on iceberg behaviour, and the factors controlling iceberg motion has been carried out. Long term and short term behaviour of icebergs are critically examined. A quantitative assessment of the effects of the factors controlling iceberg motion is presented. The study indicated that wind and currents are the primary driving forces. Coriolis Force and ocean surface slope also have significant effects. As for waves, only the higher waves have a significant effect. Iceberg drift is also affected by iceberg size characteristics. Based on the findings of the study a comprehensive computerized forecast system to predict the drift of iceberg ensembles off Canada's east coast has been designed. The expected accuracy of the forecast system is discussed and recommendations are made for future improvements to the system.

  3. Drift, Violence, and the Schools.

    ERIC Educational Resources Information Center

    Besag, Frank P.

    This paper begins by discussing David Matza's concept of "Drift" as a causal factor in violence and delinquent behavior. Matza's theory of delinquency contends that youth are prone to feelings of injustice, neutralization, preparation, and desperation. According to Matza, no one characteristic of the potential delinquent is sufficient, although…

  4. Exploring the Relationship between Access Technology and Standardized Test Scores for Youths with Visual Impairments: Secondary Analysis of the National Longitudinal Transition Study 2

    ERIC Educational Resources Information Center

    Freeland, Amy L.; Emerson, Robert Wall; Curtis, Amy B.; Fogarty, Kieran

    2010-01-01

    This article presents the findings of a secondary analysis of the National Longitudinal Transition Study 2 that explored the predictive association between training in access technology and performance on the Woodcock-Johnson Tests of Academic Achievement: III. The results indicated that the use of access technology had a limited predictive…

  5. Evaluating retailer behavior in preventing youth access to harmful legal products a feasibility test.

    PubMed

    Courser, Matthew W; Holder, Harold D; Collins, David; Johnson, Knowlton; Ogilvie, Kristen A

    2009-10-01

    This article reports results from a feasibility study of a community effort to reduce the availability of legal products that youth can use to get high. The study evaluated the potential of youth purchase attempts to detect actual changes in retail availability of harmful legal products. These results were triangulated with self-reports from retailers about their own policies and practices. Before the intervention, less than half of retailers reported using any of six possible strategies identified as ways to reduce youth access to harmful products, and less than 8% of baseline youth attempts to purchase potentially harmful legal products were refused or questioned. After the low-dosage intervention, retailers reported increased use of three strategies and a statistically significant increase in the percentage of purchase attempts that were either questioned or refused by retail clerks. These findings (a) demonstrate the potential feasibility of retailer-focused environmental strategies and (b) support continued use of youth purchase attempts as a measure of actual retailer behavior. PMID:18660467

  6. Repositioning of drugs using open-access data portal DTome: A test case with probenecid (Review).

    PubMed

    Ahmed, Mohammad U; Bennett, Dylan J; Hsieh, Tze-Chen; Doonan, Barbara B; Ahmed, Saba; Wu, Joseph M

    2016-01-01

    The one gene-one enzyme hypothesis, first introduced by Beadle and Tatum in the 1940s and based on their genetic analysis and observation of phenotype changes in Neurospora crassa challenged by various experimental conditions, has witnessed significant advances in recent decades. Much of our understanding of the association between genes and their phenotype expression has benefited from the completion of the human genome project, and has shown continual transformation guided by the effort directed at the annotation and characterization of human genes. Similarly, the idea of one drug‑one primary disease indication that traditionally has been the benchmark for the labeling and usage of drugs has also undergone evident progressive refinements; in recent years the science and practice of pharmaceutical development has notable success in the strategy of drug repurposing. Drug repurposing is an innovative approach where, instead of de novo synthesis and discovery of new drugs with novel indications, drug candidates with the desired usage are identified by a process of re‑profiling using an open‑source database or knowledge of known or failed drugs already in existence. In the present study, the repurposing drug strategy employing open‑access data portal drug‑target interactome (DTome) is applied to the uncovering of new clinical usage for probenecid. PMID:26572802

  7. Information access in a dual-task context: testing a model of optimal strategy selection

    NASA Technical Reports Server (NTRS)

    Wickens, C. D.; Seidler, K. S.

    1997-01-01

    Pilots were required to access information from a hierarchical aviation database by navigating under single-task conditions (Experiment 1) and when this task was time-shared with an altitude-monitoring task of varying bandwidth and priority (Experiment 2). In dual-task conditions, pilots had 2 viewports available, 1 always used for the information task and the other to be allocated to either task. Dual-task strategy, inferred from the decision of which task to allocate to the 2nd viewport, revealed that allocation was generally biased in favor of the monitoring task and was only partly sensitive to the difficulty of the 2 tasks and their relative priorities. Some dominant sources of navigational difficulties failed to adaptively influence selection strategy. The implications of the results are to provide tools for jumping to the top of the database, to provide 2 viewports into the common database, and to provide training as to the optimum viewport management strategy in a multitask environment.

  8. Evaluating Retailer Behavior in Preventing Youth Access to Harmful Legal Products: A Feasibility Test*

    PubMed Central

    Courser, Matthew W.; Holder, Harold D.; Collins, David; Johnson, Knowlton; Ogilvie, Kristen A.

    2008-01-01

    This paper reports results from a feasibility study of a community effort to reduce the availability of legal products that youth can use to get “high”. The study evaluated the potential of youth purchase attempts to detect actual changes in retail availability of harmful legal products. These results were triangulated with self-reports from retailers themselves about their own policies and practices. Before the intervention less than half of retailers reported using any of six possible strategies identified as ways to reduce youth access to harmful products and less than 7% of baseline youth attempts to purchase potentially harmful legal products were refused or questioned. After the low dosage intervention, retailers reported increased use of three strategies and a statistically significant increase in the percentage of purchase attempts that were either questioned or refused by retail clerks. These findings (1) demonstrate the potential feasibility of retailer focused environmental strategies and (2) support continued use of youth purchase attempts as a measure of actual retailer behavior. PMID:18660467

  9. Improving Access to Malaria Rapid Diagnostic Test in Niger State, Nigeria: An Assessment of Implementation up to 2013

    PubMed Central

    Awoleye, Olatunji Joshua; Thron, Chris

    2016-01-01

    Nigeria's 2009–2013 malaria strategic plan adopted WHO diagnosis and treatment guidelines, which include the use of rapid diagnostic tests (RDTs) prior to prescribing treatment with artemisinin combination therapies (ACTs). The current study explores accessibility barriers to the use of RDTs in Niger State and makes recommendations for improving the uptake of RDTs. The study employs literature review, review of data from the Niger State Health Management Information System for January–October 2013, and application of Peters' conceptual framework for assessing access to health services. Data showed that 27 percent of public health facilities (HFs) implemented RDTs, with the aid of donor funds. In these facilities, 77 percent of fever cases presented during the study period were tested with RDTs; 53 percent of fever cases were confirmed cases of malaria, while 60 percent of fever cases were treated. Stockouts of RDTs were a major constraint, and severe fever tended to trigger presumptive treatment. We conclude that although implementation of RDTs led to a reduction in the use of ACTs at HFs, more substantial reduction could be achieved if the state government directed more resources towards the acquisition of RDTs as well as raising the level of awareness of potential users. PMID:27042376

  10. Improving Access to Malaria Rapid Diagnostic Test in Niger State, Nigeria: An Assessment of Implementation up to 2013.

    PubMed

    Awoleye, Olatunji Joshua; Thron, Chris

    2016-01-01

    Nigeria's 2009-2013 malaria strategic plan adopted WHO diagnosis and treatment guidelines, which include the use of rapid diagnostic tests (RDTs) prior to prescribing treatment with artemisinin combination therapies (ACTs). The current study explores accessibility barriers to the use of RDTs in Niger State and makes recommendations for improving the uptake of RDTs. The study employs literature review, review of data from the Niger State Health Management Information System for January-October 2013, and application of Peters' conceptual framework for assessing access to health services. Data showed that 27 percent of public health facilities (HFs) implemented RDTs, with the aid of donor funds. In these facilities, 77 percent of fever cases presented during the study period were tested with RDTs; 53 percent of fever cases were confirmed cases of malaria, while 60 percent of fever cases were treated. Stockouts of RDTs were a major constraint, and severe fever tended to trigger presumptive treatment. We conclude that although implementation of RDTs led to a reduction in the use of ACTs at HFs, more substantial reduction could be achieved if the state government directed more resources towards the acquisition of RDTs as well as raising the level of awareness of potential users. PMID:27042376

  11. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    SciTech Connect

    E. Gonnenthal; N. Spyoher

    2001-02-05

    The purpose of this Analysis/Model Report (AMR) is to document the Near-Field Environment (NFE) and Unsaturated Zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrologic-chemical (THC) processes on unsaturated zone flow and transport. This is in accordance with the ''Technical Work Plan (TWP) for Unsaturated Zone Flow and Transport Process Model Report'', Addendum D, Attachment D-4 (Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) 2000 [153447]) and ''Technical Work Plan for Nearfield Environment Thermal Analyses and Testing'' (CRWMS M and O 2000 [153309]). These models include the Drift Scale Test (DST) THC Model and several THC seepage models. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal loading conditions, and predict the chemistry of waters and gases entering potential waste-emplacement drifts. The intended use of this AMR is to provide input for the following: (1) Performance Assessment (PA); (2) Abstraction of Drift-Scale Coupled Processes AMR (ANL-NBS-HS-000029); (3) UZ Flow and Transport Process Model Report (PMR); and (4) Near-Field Environment (NFE) PMR. The work scope for this activity is presented in the TWPs cited above, and summarized as follows: continue development of the repository drift-scale THC seepage model used in support of the TSPA in-drift geochemical model; incorporate heterogeneous fracture property realizations; study sensitivity of results to changes in input data and mineral assemblage; validate the DST model by comparison with field data; perform simulations to predict mineral dissolution and precipitation and their effects on fracture properties and chemistry of water (but not flow rates) that may seep into drifts; submit modeling results to the TDMS and document the models. The model development, input data, sensitivity and validation studies described in

  12. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    SciTech Connect

    E. Sonnenthale

    2001-04-16

    The purpose of this Analysis/Model Report (AMR) is to document the Near-Field Environment (NFE) and Unsaturated Zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrologic-chemical (THC) processes on unsaturated zone flow and transport. This is in accordance with the ''Technical Work Plan (TWP) for Unsaturated Zone Flow and Transport Process Model Report'', Addendum D, Attachment D-4 (Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M&O) 2000 [1534471]) and ''Technical Work Plan for Nearfield Environment Thermal Analyses and Testing'' (CRWMS M&O 2000 [153309]). These models include the Drift Scale Test (DST) THC Model and several THC seepage models. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal loading conditions, and predict the chemistry of waters and gases entering potential waste-emplacement drifts. The intended use of this AMR is to provide input for the following: Performance Assessment (PA); Near-Field Environment (NFE) PMR; Abstraction of Drift-Scale Coupled Processes AMR (ANL-NBS-HS-000029); and UZ Flow and Transport Process Model Report (PMR). The work scope for this activity is presented in the TWPs cited above, and summarized as follows: Continue development of the repository drift-scale THC seepage model used in support of the TSPA in-drift geochemical model; incorporate heterogeneous fracture property realizations; study sensitivity of results to changes in input data and mineral assemblage; validate the DST model by comparison with field data; perform simulations to predict mineral dissolution and precipitation and their effects on fracture properties and chemistry of water (but not flow rates) that may seep into drifts; submit modeling results to the TDMS and document the models. The model development, input data, sensitivity and validation studies described in this AMR are required

  13. Testing for Sex Inequality in Standardized Admission Exams: The Case for Open Access.

    ERIC Educational Resources Information Center

    Powell, Brian; Steelman, Lala Carr

    1982-01-01

    Compares men's and women's performance on the Law School Admission Test (LSAT), and suggests that the math section may have penalized women, since they scored equally to men on other sections. Questions the validity of mathematics performance as a predictor of success in law school and as a lawyer. (GC)

  14. Test Scores, Class Rank and College Performance: Lessons for Broadening Access and Promoting Success

    PubMed Central

    Niu, Sunny X.; Tienda, Marta

    2012-01-01

    Using administrative data for five Texas universities that differ in selectivity, this study evaluates the relative influence of two key indicators for college success—high school class rank and standardized tests. Empirical results show that class rank is the superior predictor of college performance and that test score advantages do not insulate lower ranked students from academic underperformance. Using the UT-Austin campus as a test case, we conduct a simulation to evaluate the consequences of capping students admitted automatically using both achievement metrics. We find that using class rank to cap the number of students eligible for automatic admission would have roughly uniform impacts across high schools, but imposing a minimum test score threshold on all students would have highly unequal consequences by greatly reduce the admission eligibility of the highest performing students who attend poor high schools while not jeopardizing admissibility of students who attend affluent high schools. We discuss the implications of the Texas admissions experiment for higher education in Europe. PMID:23788828

  15. HIV Risk Behavior and Access to Services: What Predicts HIV Testing among Heterosexually Active Homeless Men?

    ERIC Educational Resources Information Center

    Wenzel, Suzanne L.; Rhoades, Harmony; Tucker, Joan S.; Golinelli, Daniela; Kennedy, David P.; Zhou, Annie; Ewing, Brett

    2012-01-01

    HIV is a serious epidemic among homeless persons, where rates of infection are estimated to be three times higher than in the general population. HIV testing is an effective tool for reducing HIV transmission and for combating poor HIV/AIDS health outcomes that disproportionately affect homeless persons, however, little is known about the HIV…

  16. Accessing Early Behavioral Intervention for Autism: The Development and Testing of a Psychoeducational Website

    ERIC Educational Resources Information Center

    Steever, Michele Pasquale

    2009-01-01

    Little is known about the utility of psychoeducation within a stepped care model as applied to the problem of autism treatment. The current study developed and pilot tested a psychoeducational website for parents who recently had a child diagnosed with autism. A nonconcurrent multiple baseline across participants design was used to evaluate the…

  17. Enhancing the Accessibility of High School Science Tests: A Multistate Experiment

    ERIC Educational Resources Information Center

    Kettler, Ryan J.; Dickenson, Tammiee S.; Bennett, Heather L.; Morgan, Grant B.; Gilmore, Joanna A.; Beddow, Peter A.; Swaffield, Suzanne; Turner, Linda; Herrera, Bill; Turner, Charlene; Palmer, Porter W.

    2012-01-01

    This study was inspired by the final regulations for the No Child Left Behind Act (NCLB) indicating that each state has the option to develop a new assessment for students whose disabilities have kept them from obtaining proficiency. Sets of high school science achievement items were enhanced for the new test. A 3-by-2, within subjects,…

  18. Standardizing Interfaces for External Access to Data and Processing for the NASA Ozone Product Evaluation and Test Element (PEATE)

    NASA Technical Reports Server (NTRS)

    Tilmes, Curt A.; Fleig, Albert J.

    2008-01-01

    NASA's traditional science data processing systems have focused on specific missions, and providing data access, processing and services to the funded science teams of those specific missions. Recently NASA has been modifying this stance, changing the focus from Missions to Measurements. Where a specific Mission has a discrete beginning and end, the Measurement considers long term data continuity across multiple missions. Total Column Ozone, a critical measurement of atmospheric composition, has been monitored for'decades on a series of Total Ozone Mapping Spectrometer (TOMS) instruments. Some important European missions also monitor ozone, including the Global Ozone Monitoring Experiment (GOME) and SCIAMACHY. With the U.S.IEuropean cooperative launch of the Dutch Ozone Monitoring Instrument (OMI) on NASA Aura satellite, and the GOME-2 instrumental on MetOp, the ozone monitoring record has been further extended. In conjunction with the U.S. Department of Defense (DoD) and the National Oceanic and Atmospheric Administration (NOAA), NASA is now preparing to evaluate data and algorithms for the next generation Ozone Mapping and Profiler Suite (OMPS) which will launch on the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP) in 2010. NASA is constructing the Science Data Segment (SDS) which is comprised of several elements to evaluate the various NPP data products and algorithms. The NPP SDS Ozone Product Evaluation and Test Element (PEATE) will build on the heritage of the TOMS and OM1 mission based processing systems. The overall measurement based system that will encompass these efforts is the Atmospheric Composition Processing System (ACPS). We have extended the system to include access to publically available data sets from other instruments where feasible, including non-NASA missions as appropriate. The heritage system was largely monolithic providing a very controlled processing flow from data.ingest of

  19. Evolution: drift will tear us apart.

    PubMed

    Maderspacher, Florian

    2012-11-01

    That the widely scattered geographical distribution of some animals could be due to continental drift is a neat idea. Now, cave animals provide evidence for extreme long-term persistence on continents drifting apart. PMID:23137684

  20. Diel drift of Chironomidae larvae in a pristine Idaho mountain stream

    USGS Publications Warehouse

    Tilley, L.J.

    1989-01-01

    Simultaneous hourly net collections in a meadow and canyon reach of a mountain stream determined diel and spatial abundances of drifting Chironomidae larvae. Sixty-one taxa were identified to the lowest practical level, 52 in the meadow and 41 in the canyon. Orthocladiinae was the most abundant subfamily with 32 taxa and a 24 h mean density of 294 individuals 100 m-3 (meadow) and 26 taxa and a mean of 648 individuals 100 m-3 (canyon). Chironominae was the second most abundant subfamily. Nonchironomid invertebrates at both sites and total Chironomidae larvae (meadow) were predominantly night-drifting. Parakiefferiella and Psectrocladius were day-drifting (meadow) whereas 8 other chironomid taxa (meadow) and 2 taxa (canyon) were night-drifting. All others were aperiodic or too rare to test periodicity, Stempellinella cf brevis Edwards exhibited catastrophic drift in the canyon only. The different drift patterns between sites is attributed to greater loss of streambed habitat in the canyon compared to the meadow as streamflow decreased. Consequent crowding of chironomid larvae in the canyon caused catastrophic drift or interfered with drift periodicty. This study adds to knowledge of Chironomidae drift and shows influences on drift of hydrologic and geomorphic conditions. ?? 1989 Kluwer Academic Publishers.

  1. Spray drift mitigation with spray mix adjuvants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous drift reduction adjuvants and spray deposition aids are available to applicators of crop production and protection chemicals. Performance of many of the newly introduced drift control adjuvants has not been well documented for aerial application. Four new drift control adjuvants were sele...

  2. Electrometer preamplifier has drift correction feedback

    NASA Technical Reports Server (NTRS)

    Labarthe, L. C.

    1965-01-01

    Negative feedback circuit corrects output drift in an electrometer. The negative feedback is used in the no signal state to maintain the output level at zero reference. Drift voltage storage in the signal on state is also used to provide a drift-free readout.

  3. Generalized banana-drift transport

    SciTech Connect

    Mynick, H.E.

    1985-10-01

    The theory of tokamak ripple transport in the banana-drift and ripple-plateau regimes is extended in a number of directions. The theory is valid for small values of the toroidal periodicity number n of the perturbation, as well as for the moderate values (n approx. 10 to 20) previously assumed. It is shown that low-n perturbations can produce much greater transport than the larger-n perturbations usually studied. In addition, the ripple perturbation is allowed arbitrary values of poloidal mode number m and frequency ..omega.., making it applicable to the transport induced by MHD modes. Bounce averaging is avoided, so the theory includes the contributions to transport from all harmonics of the bounce frequency, providing a continuous description of the transition from the banana drift to the ripple-plateau regime. The implications of the theory for toroidal rotation in tokamaks are considered.

  4. Factors Enabling Access to HIV Voluntary Counseling and Testing for Key Affected Populations in Thailand.

    PubMed

    Thepthien, Bang-on; Srivanichakorn, Supattra; Apipornchaisakul, Kanya

    2015-10-01

    The objective was to study the factors that enabled persons at risk of HIV to obtain voluntary counseling and testing (VCT) in Thailand. This research was a cross-sectional study and data were collected during May to July 2013 in 8, purposively selected provinces. The method for selecting respondents used time-location quota sampling to achieve a total sample of 751 persons. The proportion who had VCT in the year prior to the survey was 56%.The significant enabling factors associated with VCT were having someone encourage them to go for testing and receiving information about VCT In addition, other significant factors for female sex workers were self-assessed risk for HIV and having had risk behavior, and for men who have sex with men the factors were awareness of eligibility for VCT. Thus, in order to achieve the VCT target for higher risk populations by 2016, there should be special mechanisms to inform the different groups, along with improvements in outreach services to make VCT more convenient for key affected populations. PMID:26069165

  5. MPS II drift chamber system

    SciTech Connect

    Platner, E.D.

    1982-01-01

    The MPS II detectors are narrow drift space chambers designed for high position resolution in a magnetic field and in a very high particle flux environment. Central to this implementation was the development of 3 multi-channel custom IC's and one multi-channel hybrid. The system is deadtimeless and requires no corrections on an anode-to-anode basis. Operational experience and relevance to ISABELLE detectors is discussed.

  6. Random drift and culture change.

    PubMed

    Bentley, R Alexander; Hahn, Matthew W; Shennan, Stephen J

    2004-07-22

    We show that the frequency distributions of cultural variants, in three different real-world examples--first names, archaeological pottery and applications for technology patents--follow power laws that can be explained by a simple model of random drift. We conclude that cultural and economic choices often reflect a decision process that is value-neutral; this result has far-reaching testable implications for social-science research. PMID:15306315

  7. Random drift and culture change.

    PubMed Central

    Bentley, R. Alexander; Hahn, Matthew W.; Shennan, Stephen J.

    2004-01-01

    We show that the frequency distributions of cultural variants, in three different real-world examples--first names, archaeological pottery and applications for technology patents--follow power laws that can be explained by a simple model of random drift. We conclude that cultural and economic choices often reflect a decision process that is value-neutral; this result has far-reaching testable implications for social-science research. PMID:15306315

  8. Ionospheric Plasma Drift Analysis Technique Based On Ray Tracing

    NASA Astrophysics Data System (ADS)

    Ari, Gizem; Toker, Cenk

    2016-07-01

    Ionospheric drift measurements provide important information about the variability in the ionosphere, which can be used to quantify ionospheric disturbances caused by natural phenomena such as solar, geomagnetic, gravitational and seismic activities. One of the prominent ways for drift measurement depends on instrumentation based measurements, e.g. using an ionosonde. The drift estimation of an ionosonde depends on measuring the Doppler shift on the received signal, where the main cause of Doppler shift is the change in the length of the propagation path of the signal between the transmitter and the receiver. Unfortunately, ionosondes are expensive devices and their installation and maintenance require special care. Furthermore, the ionosonde network over the world or even Europe is not dense enough to obtain a global or continental drift map. In order to overcome the difficulties related to an ionosonde, we propose a technique to perform ionospheric drift estimation based on ray tracing. First, a two dimensional TEC map is constructed by using the IONOLAB-MAP tool which spatially interpolates the VTEC estimates obtained from the EUREF CORS network. Next, a three dimensional electron density profile is generated by inputting the TEC estimates to the IRI-2015 model. Eventually, a close-to-real situation electron density profile is obtained in which ray tracing can be performed. These profiles can be constructed periodically with a period of as low as 30 seconds. By processing two consequent snapshots together and calculating the propagation paths, we estimate the drift measurements over any coordinate of concern. We test our technique by comparing the results to the drift measurements taken at the DPS ionosonde at Pruhonice, Czech Republic. This study is supported by TUBITAK 115E915 and Joint TUBITAK 114E092 and AS CR14/001 projects.

  9. Grain Size of the North-Atlantic Drifts Sediments: is the Gloria Drift a Contourite Drift?

    NASA Astrophysics Data System (ADS)

    Dorokhova, E.; Sivkov, V.; Bashirova, L.

    2015-12-01

    Mean size of mineral particles of 10-63 fraction, so-called sortable silt mean size (SS) (McCave, 1995) and modes of grain-size distribution were used as proxies for reconstruction of paleocurrents intensity variations in the North Atlantic. It was assumed that the first mode (3-8 μm) is formed as the result of normal pelagic sedimentation and the second mode (10-30 μm) appears under the bottom currents influence. The sediments with bimodal grain-size distribution (the second mode varies from 10 to 28 μm) correlate with increased SS (up to 18-23 μm) in the Hatton and Snorry Drifts, indicating an increase in contour currents intensity during MIS 1, 3 and 5e. In contrast, there are no any relationships between grain size distribution (high SS values, appearance of bimodal distributions) and climatic cyclicity of variations in contour currents intensity at the Gloria Drift. Moreover, the Gloria Drift sediments differ from the contourite sediments of the Snorry and Hatton Drifts by shifting of the second mode toward the coarse particles (25-40 μm), higher sedimentation rates and higher IRD content. This evidence puts in doubt the contourite origin of the Gloria Drift. At the same time, we have identified the similarity between the Gloria Drift sediments and IRD-containing hemiturbidites of Labrador Sea (Hesse and Khodabakhsh, 2006). Fine-grained sediment lofting has been inferred for ice marginal regions of the northwest Labrador Sea. Sediment failure on the Labrador Slope predominantly produces muddy turbidity currents, because the slope sediments are mud-dominated. Their deposits are the indicative muddy spill-over turbidites of the NAMOC levees and the levees of the tributaries to the NAMOC. Dispersal of the IRD throughout the graded mud layers is evidence that the two processes, ice rafting and the delivery of the fines by lofting, occurred simultaneously. This work was supported by Russian Scientific Fund (grant No. 14-50-00095).

  10. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1988-10-01

    A laced permanent magnet quadrupole drift tube magnet has been constructed for a proof-of-principle test. The magnet is a conventional tape-wound quadrupole electromagnet, using iron pole- pieces, with the addition of permanent magnet material (neodymium iron) between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the quadrupole magnets in a drift tube linac is not reversed we can take advantage of this asymmetrical saturation to provide greater focusing strength. The magnet configuration has been optimized and the vanadium permendur poles needed in a conventional quadrupole have been replaced with iron poles. The use of permanent magnet material has allowed us to increase the focusing strength of the magnet by about 20% over that of a conventional tape-wound quadrupole. Comparisons will be made between this magnet and the conventional tape-wound quadrupole. 3 refs., 5 figs.

  11. New drift chamber for the Mark II at SLC

    SciTech Connect

    Hanson, G.G.

    1984-04-01

    A new cylindrical drift chamber is being constructed for the Mark II detector for use at the new SLAC Linear Collider. The design of the new chamber is based on a multi-sense-wire cell of the jet-chamber type. In addition to drift-time measurements, pulse height measurements from the sense wires will provide electron-hadron separation by dE/dx. The design and construction of the chamber, tests of prototypes, and chamber electronics are discussed. 7 references, 12 figures.

  12. New central drift chamber for the MARK II at SLC

    SciTech Connect

    Bartelt, J.E.

    1986-09-01

    A new central drift chamber has been constructed for the Mark II detector for use at the new SLAC Linear Collider (SLC). The design of the chamber is based on a multi-sense-wire cell of the jet chamber type. In addition to drift-time measurements, pulse-height measurements from the sense wires provide electron-hadron separation by dE/dx. The chamber has been tested in operation at PEP before its move to the SLC. The design and construction are described, and measurements from the new chamber are presented.

  13. Scroll wave drift along steps, troughs, and corners

    NASA Astrophysics Data System (ADS)

    Ke, Hua; Zhang, Zhihui; Steinbock, Oliver

    2015-06-01

    Three-dimensional excitable systems can create nonlinear scroll waves that rotate around one-dimensional phase singularities. Recent theoretical work predicts that these filaments drift along step-like height variations. Here, we test this prediction using experiments with thin layers of the Belousov-Zhabotinsky reaction. We observe that over short distances scroll waves are attracted towards the step and then rapidly commence a steady drift along the step line. The translating filaments always reside on the shallow side of the step near the edge. Accordingly, filaments in the deep domain initially collide with and shorten at the step wall. The drift speeds obey the predicted proportional dependence on the logarithm of the height ratio and the direction depends on the vortex chirality. We also observe drift along the perimeter of rectangular plateaus and find that the filaments perform sharp turns at the corners. In addition, we investigate rectangular troughs for which vortices of equal chirality can drift in different directions. The latter two effects are reproduced in numerical simulations with the Barkley model. The simulations show that narrow troughs instigate scroll wave encounters that induce repulsive interaction and symmetry breaking. Similar phenomena could exist in the geometrically complicated ventricles of the human heart where reentrant vortex waves cause tachycardia and fibrillation.

  14. An Investigation of Scale Drift for Arithmetic Assessment of ACCUPLACER®. Research Report No. 2010-2

    ERIC Educational Resources Information Center

    Deng, Hui; Melican, Gerald

    2010-01-01

    The current study was designed to extend the current literature to study scale drift in CAT as part of improving quality control and calibration process for ACCUPLACER, a battery of large-scale adaptive placement tests. The study aims to evaluate item parameter drift using empirical data that span four years from the ACCUPLACER Arithmetic…

  15. Flight Services and Aircraft Access: Active Flow Control Vertical Tail and Insect Accretion and Mitigation Flight Test

    NASA Technical Reports Server (NTRS)

    Whalen, Edward A.

    2016-01-01

    This document serves as the final report for the Flight Services and Aircraft Access task order NNL14AA57T as part of NASA Environmentally Responsible Aviation (ERA) Project ITD12A+. It includes descriptions of flight test preparations and execution for the Active Flow Control (AFC) Vertical Tail and Insect Accretion and Mitigation (IAM) experiments conducted on the 757 ecoDemonstrator. For the AFC Vertical Tail, this is the culmination of efforts under two task orders. The task order was managed by Boeing Research & Technology and executed by an enterprise-wide Boeing team that included Boeing Research & Technology, Boeing Commercial Airplanes, Boeing Defense and Space and Boeing Test and Evaluation. Boeing BR&T in St. Louis was responsible for overall Boeing project management and coordination with NASA. The 757 flight test asset was provided and managed by the BCA ecoDemonstrator Program, in partnership with Stifel Aircraft Leasing and the TUI Group. With this report, all of the required deliverables related to management of this task order have been met and delivered to NASA as summarized in Table 1. In addition, this task order is part of a broader collaboration between NASA and Boeing.

  16. Precipitates/Salts Model Calculations for Various Drift Temperature Environments

    SciTech Connect

    P. Marnier

    2001-12-20

    The objective and scope of this calculation is to assist Performance Assessment Operations and the Engineered Barrier System (EBS) Department in modeling the geochemical effects of evaporation within a repository drift. This work is developed and documented using procedure AP-3.12Q, Calculations, in support of ''Technical Work Plan For Engineered Barrier System Department Modeling and Testing FY 02 Work Activities'' (BSC 2001a). The primary objective of this calculation is to predict the effects of evaporation on the abstracted water compositions established in ''EBS Incoming Water and Gas Composition Abstraction Calculations for Different Drift Temperature Environments'' (BSC 2001c). A secondary objective is to predict evaporation effects on observed Yucca Mountain waters for subsequent cement interaction calculations (BSC 2001d). The Precipitates/Salts model is documented in an Analysis/Model Report (AMR), ''In-Drift Precipitates/Salts Analysis'' (BSC 2001b).

  17. Understanding structural barriers to accessing HIV testing and prevention services among black men who have sex with men (BMSM) in the United States.

    PubMed

    Levy, Matthew E; Wilton, Leo; Phillips, Gregory; Glick, Sara Nelson; Kuo, Irene; Brewer, Russell A; Elliott, Ayana; Watson, Christopher; Magnus, Manya

    2014-05-01

    Structural-level factors have contributed to the substantial disproportionate rates of HIV among Black men who have sex with men (BMSM) in the United States. Despite insufficient HIV testing patterns, however, there is a void in research investigating the relationship between structural factors and access to HIV testing and prevention services among BMSM. Building on previous scholarly work and incorporating a dynamic social systems conceptual framework, we conducted a comprehensive review of the literature on structural barriers to HIV testing and prevention services among BMSM across four domains: healthcare, stigma and discrimination, incarceration, and poverty. We found that BMSM experience inadequate access to culturally competent services, stigma and discrimination that impede access to services, a deficiency of services in correctional institutions, and limited services in areas where BMSM live. Structural interventions that eliminate barriers to HIV testing and prevention services and provide BMSM with core skills to navigate complex systems are needed. PMID:24531769

  18. Understanding Structural Barriers to Accessing HIV Testing and Prevention Services Among Black Men Who Have Sex with Men (BMSM) in the United States

    PubMed Central

    Wilton, Leo; Phillips, Gregory; Glick, Sara Nelson; Kuo, Irene; Brewer, Russell A.; Elliott, Ayana; Watson, Christopher; Magnus, Manya

    2015-01-01

    Structural-level factors have contributed to the substantial disproportionate rates of HIV among Black men who have sex with men (BMSM) in the United States. Despite insufficient HIV testing patterns, however, there is a void in research investigating the relationship between structural factors and access to HIV testing and prevention services among BMSM. Building on previous scholarly work and incorporating a dynamic social systems conceptual framework, we conducted a comprehensive review of the literature on structural barriers to HIV testing and prevention services among BMSM across four domains: healthcare, stigma and discrimination, incarceration, and poverty. We found that BMSM experience inadequate access to culturally competent services, stigma and discrimination that impede access to services, a deficiency of services in correctional institutions, and limited services in areas where BMSM live. Structural interventions that eliminate barriers to HIV testing and prevention services and provide BMSM with core skills to navigate complex systems are needed. PMID:24531769

  19. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Research Team . Volume 2; Appendices

    NASA Technical Reports Server (NTRS)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage (horizontal and vertical tail). This report contains the Appendices to Volume I.

  20. Redshift drift constraints on f( T) gravity

    NASA Astrophysics Data System (ADS)

    Geng, Jia-Jia; Guo, Rui-Yun; He, Dong-Ze; Zhang, Jing-Fei; Zhang, Xin

    2015-10-01

    We explore the impact of the Sandage-Loeb (SL) test on the precision of cosmological constraints for f( T) gravity theories. The SL test is an important supplement to current cosmological observations because it measures the redshift drift in the Lyman-α forest in the spectra of distant quasars, covering the "redshift desert" of 2 ≤ z ≤ 5. To avoid data inconsistency, we use the best-fit models based on current combined observational data as fiducial models to simulate 30 mock SL test data. We quantify the impact of these SL test data on parameter estimation for f( T) gravity theories. Two typical f( T) models are considered, the power-law model f( T) PL and the exponential-form model f( T) EXP . The results show that the SL test can effectively break the existing strong degeneracy between the present-day matter density Ω m and the Hubble constant H 0 in other cosmological observations. For the considered f( T) models, a 30-year observation of the SL test can improve the constraint precision of Ω m and H 0 enormously but cannot effectively improve the constraint precision of the model parameters.

  1. Spiral biasing adaptor for use in Si drift detectors and Si drift detector arrays

    DOEpatents

    Li, Zheng; Chen, Wei

    2016-07-05

    A drift detector array, preferably a silicon drift detector (SDD) array, that uses a low current biasing adaptor is disclosed. The biasing adaptor is customizable for any desired geometry of the drift detector single cell with minimum drift time of carriers. The biasing adaptor has spiral shaped ion-implants that generate the desired voltage profile. The biasing adaptor can be processed on the same wafer as the drift detector array and only one biasing adaptor chip/side is needed for one drift detector array to generate the voltage profiles on the front side and back side of the detector array.

  2. The Fallacy of Drifting Snow

    NASA Astrophysics Data System (ADS)

    Andreas, Edgar L.

    2011-12-01

    A common parametrization over snow-covered surfaces that are undergoing saltation is that the aerodynamic roughness length for wind speed ( z 0) scales as {α u_ast^2/g}, where u * is the friction velocity, g is the acceleration of gravity, and α is an empirical constant. Data analyses seem to support this scaling: many published plots of z 0 measured over snow demonstrate proportionality to {u_ast^2 }. In fact, I show similar plots here that are based on two large eddy-covariance datasets: one collected over snow-covered Arctic sea ice; another collected over snow-covered Antarctic sea ice. But in these and in most such plots from the literature, the independent variable, u *, was used to compute z 0 in the first place; the plots thus suffer from fictitious correlation that causes z 0 to unavoidably increase with u * without any intervening physics. For these two datasets, when I plot z 0 against u * derived from a bulk flux algorithm—and thus minimize the fictitious correlation— z 0 is independent of u * in the drifting snow region, u * ≥ 0.30 ms-1. I conclude that the relation {z_0 = α u_ast^2/g} when snow is drifting is a fallacy fostered by analyses that suffer from fictitious correlation.

  3. Investigations of SPS Orbit Drifts

    SciTech Connect

    Drøsdal, Lene; Bracco, Chiara; Cornelis, Karel; Goddard, Brennan; Kain, Verena; Meddahi, Malika; Wenninger, Jorg; Gianfelice-Wendt, Eliana

    2014-07-01

    The LHC is filled from the last pre-injector, the Super Proton Synchrotron (SPS), via two 3 km long transfer lines, TI 2 and TI 8. Over the LHC injection processes, a drift of the beam trajectories has been observed in TI 2 and TI 8, requiring regular correction of the trajectories, in order to ensure clean injection into the LHC. Investigations of the trajectory variations in the transfer lines showed that the main source of short term trajectory drifts are current variations of the SPS extraction septa (MSE). The stability of the power converters has been improved, but the variations are still present and further improvements are being investigated. The stability over a longer period of time cannot be explained by this source alone. The analysis of trajectory variations shows that there are also slow variations in the SPS closed orbit at extraction. A set of SPS orbit measurements has been saved and analysed. These observations will be used together with simulations and observed field errors to locate the second source of variations.

  4. Simulation of the DRIFT Experiment

    NASA Astrophysics Data System (ADS)

    Hyatt, Matt; Ayad, Rachid; Hanson-Hart, Zach; Katz-Hyman, Moshe; Posner, Aaron; Martoff, C. J.

    2003-04-01

    The DRIFT Experiment [1] is an underground search for WIMP Dark Matter using a novel detector invented for this purpose: the Negative Ion TPC (NITPC). To aid in interpreting the results, a simulation code system has been developed. The system uses the CERNLIB program GEANT [2] and the NRC package EGS4 [3] to simulate particle interactions in the detector. These are linked directly to the CERNLIB program GARFIELD, which simulates signal production in the NITPC. Finally the GARFIELD output is converted into the format of the DRIFT DAQ for presentation to the analysis code. The physics and software issues dealt with in this development will be discussed. [1] Low Pressure Negative Ion TPC for Dark Matter Search. D. P. Snowden-Ifft, C. J. Martoff, J. M. Burwell, Phys Rev. D. Rapid Comm. 61, 101301 (2000) [2] GEANT Manual, CERN Program Library Long Writeup W5013, Copyright CERN, Geneva, 1993 . [3] EGS4, National Research Council, Canada. Note PIRS-701. http://www.irs.inms.nrc.ca/inms/irs/EGS4/get_egs4.html . [4] GARFIELD Manual, version 7.04, CERN Program Library Long Writeup W5050, Copyright CERN, Geneva, 2001 .

  5. Acceptance test report (MI-74067-009-00). SVWS access arm (Serial number AA-09-03) (drawing 75M08129-13)

    NASA Technical Reports Server (NTRS)

    Hagood, J. T.

    1973-01-01

    Acceptance tests were conducted at Kennedy Space Center of the Saturn Vehicle Workshop Spacecraft Access Arm and related equipment. The tests were conducted to prove complete system capability to operate satisfactorily under conditions required to support spacecraft operations and activities. The SVWS Access Arm, serial number AA-09-03, is a Command Module Service Arm, S/A 9, which was removed from the mobile launcher and modified to support the SVWS operations. The C/M environmental chamber was removed and a completely new chamber was installed. The retract system was redesigned to remove the automatic/remote control capability and replaced with a local manual control. The SVWS Access Arm System was successfully tested and supported spacecraft processing without major problems.

  6. Flow and transport in the drift shadow in a dual-continuum model

    SciTech Connect

    Houseworth, J.E.; Finsterle, S.; Bodvarsson, G.S.

    2002-09-01

    The current concept for high-level radioactive waste disposal at Yucca Mountain is for the waste to be placed in underground tunnels (or drifts) in the middle of a thick unsaturated zone. Flow modeling and field testing have shown that not all flow encountering a drift will seep into the drift. The underlying reason for the diversion of unsaturated flow around a drift is that capillary forces in the fractures and matrix prevent water entry into the drift unless the capillary pressure in the rock decreases sufficiently to allow for gravity forces to overcome the capillary barrier. As a result of the capillary barrier effect, flow tends to be diverted around the drift, affecting the flow pattern beneath the drift. For some distance beneath the drift, water saturation and flux are reduced. This drift shadow zone is much more pronounced in the fractures than in the matrix due to dominance of gravity over capillary forces in the fractures. Moving downward, away from the drift, the shadow zone asymptotically re-equilibrates to the undisturbed flow conditions due to capillary forces. The behavior of radionuclide transport in this zone of reduced flow is investigated here because this will affect the amount of time required for radionuclides to penetrate the unsaturated zone. The delay of radio nuclide movement in the geosphere is one aspect of the potential repository system that could limit public exposure to radioactive waste. The behavior of flow and transport are calculated using a two-dimensional, drift-scale dual permeability model extending to nine drift diameters below the potential waste emplacement drift. The flow model is first compared with an analytical model for a single-continuum. Then the dual-continuum flow model is investigated with respect to drift-scale and mountain-scale property sets. Transport calculations are performed for a wide range of flow conditions and for different aqueous radionuclides and colloids. Findings indicate that transport times

  7. WORLD SURFACE CURRENTS FROM SHIP'S DRIFT OBSERVATIONS

    SciTech Connect

    Duncan, C.P.; Schladow, S.G.

    1980-11-01

    Over 4 million observations of ship's drift are on file at the U.S. National Oceanographic Data Centre, in Washington, D. C., representing a vast amount of information on ocean surface currents. The observed drift speeds are dependent on the frequency of occurence of the particular current speeds and the frequency of observation. By comparing frequency of observation with the drift speeds observed it is possible to confirm known current patterns and detect singularities in surface currents.

  8. Drift chamber tracking with neural networks

    SciTech Connect

    Lindsey, C.S.; Denby, B.; Haggerty, H.

    1992-10-01

    We discuss drift chamber tracking with a commercial log VLSI neural network chip. Voltages proportional to the drift times in a 4-layer drift chamber were presented to the Intel ETANN chip. The network was trained to provide the intercept and slope of straight tracks traversing the chamber. The outputs were recorded and later compared off line to conventional track fits. Two types of network architectures were studied. Applications of neural network tracking to high energy physics detector triggers is discussed.

  9. THERMAL EVALUATION OF DIFFERENT DRIFT DIAMETER SIZES

    SciTech Connect

    H.M. Wade

    1999-01-04

    The purpose of this calculation is to estimate the thermal response of a repository-emplaced waste package and its corresponding drift wall surface temperature with different drift diameters. The case examined is that of a 21 pressurized water reactor (PWR) uncanistered fuel (UCF) waste package loaded with design basis spent nuclear fuel assemblies. This calculation evaluates a 3.5 meter to 6.5 meter drift diameter range in increments of 1.0 meters. The time-dependent temperatures of interest, as determined by this calculation, are the spent nuclear fuel cladding temperature, the waste package surface temperature, and the drift wall surface temperature.

  10. Ability or Access-Ability: Differential Item Functioning of Items on Alternate Performance-Based Assessment Tests for Students with Visual Impairments

    ERIC Educational Resources Information Center

    Zebehazy, Kim T.; Zigmond, Naomi; Zimmerman, George J.

    2012-01-01

    Introduction: This study investigated differential item functioning (DIF) of test items on Pennsylvania's Alternate System of Assessment (PASA) for students with visual impairments and severe cognitive disabilities and what the reasons for the differences may be. Methods: The Wilcoxon signed ranks test was used to analyze differences in the scores…

  11. Tools for assessing the quality and accessibility of online health information: initial testing among breast cancer websites.

    PubMed

    Whitten, Pamela; Nazione, Samantha; Lauckner, Carolyn

    2013-12-01

    Health websites are used frequently, but there are many concerns about their value as information sources. Additionally, there are numerous personal barriers that prevent individuals from wholly benefitting from them. In order to assess the quality of health websites and their accessibility to users, we created tools based on previous research that examine design aspects, information validity, motivational health content and literacy content. To test these tools, we examined 155 breast cancer websites and created scores for each assessment tool to describe the percent of constructs on the average website. Results demonstrated that websites performed best on the design tool followed by the information validity, motivational health content and literacy assessment tools. The average website contained the majority of the design and information validity constructs, but only about a third of the motivational health or literacy constructs. Multiple items from the motivational health content and literacy assessment tools were not found on any of the websites, and many were only represented on a handful of sites. Overall, the assessment tools were useful in evaluating the quality of websites, and could serve as valuable resources for health website developers in the future. PMID:23957628

  12. Access to edge scenarios for testing a scraper element in early operation phases of Wendelstein 7-X

    NASA Astrophysics Data System (ADS)

    Hölbe, H.; Pedersen, T. Sunn; Geiger, J.; Bozhenkov, S.; König, R.; Feng, Y.; Lore, J.; Lumsdaine, A.; the Wendelstein 7-X Team

    2016-02-01

    The edge topology of magnetic fusion devices is decisive for the control of the plasma exhaust. In Wendelstein 7-X, the island divertor concept will be used, for which the edge topology can change significantly as the internal currents in a plasma discharge evolve towards steady-state. Consequently, the device has been optimized to minimize such internal currents, in particular the bootstrap current [1]. Nonetheless, there are predicted pulse scenarios where effects of the remaining internal currents could potentially lead to overload of plasma-facing components. These internal currents are predicted to evolve on long time scales (tens of seconds) so their effects on the edge topology and the divertor heat loads may not be experimentally accessible in the first years of W7-X operation, where only relatively short pulses are possible. However, we show here that for at least one important long-pulse divertor operation issue, relevant physics experiments can be performed already in short-pulse operation, through judicious adjustment of the edge topology by the use of the existing coil sets. The specific issue studied here is a potential overload of the divertor element edges. This overload might be mitigated by the installation of an extra set of plasma-facing components, so-called scraper elements, as suggested in earlier publications. It is shown here that by a targeted control of edge topology, the effectiveness of such scraper elements can be tested already with uncooled test-scraper elements in short-pulse operation. This will allow an early and well-informed decision on whether long-pulse-capable (actively cooled) scraper elements should be built and installed.

  13. Access to edge scenarios for testing a scraper element in early operation phases of Wendelstein 7-X

    DOE PAGESBeta

    Holbe, H.; Pedersen, T. Sunn; Geiger, J.; Bozhenkov, S.; Kornejew, P; Feng, Y.; Lore, Jeremy D.; Lumsdaine, Arnold; Konig, R.

    2016-01-29

    The edge topology of magnetic fusion devices is decisive for the control of the plasma exhaust. In Wendelstein 7-X, the island divertor concept will be used, for which the edge topology can change significantly as the internal currents in a plasma discharge evolve towards steady-state. Consequently, the device has been optimized to minimize such internal currents, in particular the bootstrap current [1]. Nonetheless, there are predicted pulse scenarios where effects of the remaining internal currents could potentially lead to overload of plasma-facing components. These internal currents are predicted to evolve on long time scales (tens of seconds) so their effectsmore » on the edge topology and the divertor heat loads may not be experimentally accessible in the first years of W7-X operation, where only relatively short pulses are possible. However, we show here that for at least one important long-pulse divertor operation issue, relevant physics experiments can be performed already in short-pulse operation, through judicious adjustment of the edge topology by the use of the existing coil sets. The specific issue studied here is a potential overload of the divertor element edges. This overload might be mitigated by the installation of an extra set of plasma-facing components, so-called scraper elements, as suggested in earlier publications. It is shown here that by a targeted control of edge topology, the effectiveness of such scraper elements can be tested already with uncooled test-scraper elements in short-pulse operation. Furthermore, this will allow an early and well-informed decision on whether long-pulse-capable (actively cooled) scraper elements should be built and installed.« less

  14. Drift and proportional tracking chambers

    NASA Astrophysics Data System (ADS)

    Jaros, J. A.

    1980-11-01

    The many techniques exploited in constructing tracking chambers, particle detectors which measure the trajectories and momenta of charged particles, are discussed. In high energy interactions, the final states are dominated by closely collimated jets of high multiplicity, requiring good track-pair resolution in the tracking chamber. High energy particles deflect very little in limited magnetic field volumes, necessitating good spatial resolution for accurate momentum measurements. The colliding beam technique requires a device easily adapted to full solid angle coverage, and the high event rates expected in some of these machines put a premium on good time resolution. Finally, the production and subsequent decays of the tau, charmed and beautiful mesons provide multiple vertex topologies. To reconstruct these vertices reliably requires improvements in spatial resolution and track pair resolution. The proportional counter and its descendant, the drift chamber, are considered as tracking chambers. The physics of this device are discussed in order to understand its performance limitations and promises.

  15. Access to HIV counseling and testing among people who inject drugs in Central Asia: Strategies for improving access and linkages to treatment and care

    PubMed Central

    Terlikbayeva, Assel; Zhussupov, Baurzhan; Primbetova, Sholpan; Gilbert, Louisa; Atabekov, Nurmat; Giyasova, Gusal; Ruziev, Murodali; Soliev, Alijon; Saliev, Daniiar; El-Bassel, Nabila

    2013-01-01

    Introduction As a population profoundly affected by the HIV epidemic and in critical need of linkages to HIV treatment and care, PWID in Central Asia remain largely underserved. This paper provides an overview of the current state of HIV testing and counseling in Central Asia for PWID, identifies main barriers leading to gaps in service delivery, and discusses implications for improving strategies that promote HIV testing for PWID. Methods We reviewed a number of sources for this paper including unpublished government reports, published papers, and Ministries of Health of Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan country progress reports to the UN General Assembly Special Session on HIV/AIDS (UNGASS) for 2012. Results Between 29 to 65% of PLWH in some Central Asian countries have been tested for HIV in the last 12 months. The rates have been increasing in the recent years but still are relatively low. Stigma, discrimination, human rights violations, and repressive legislation are barriers to HTC for people who inject drugs (PWID). Conclusion The use of innovative evidence-based HTC models, such as community mobile-vans, self-testing at home, and rapid HIV testing among PWID in Central Asia are discussed and recommendations given regarding amendments in legislation and scaling up of existing community-based pilot projects to support HIV testing among PWID in CA. PMID:23916319

  16. 40 CFR 1065.550 - Gas analyzer range validation, drift validation, and drift correction.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Gas analyzer range validation, drift validation, and drift correction. 1065.550 Section 1065.550 Protection of Environment ENVIRONMENTAL... Over Specified Duty Cycles § 1065.550 Gas analyzer range validation, drift validation, and...

  17. 40 CFR 1065.550 - Gas analyzer range validation, drift validation, and drift correction.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Gas analyzer range validation, drift validation, and drift correction. 1065.550 Section 1065.550 Protection of Environment ENVIRONMENTAL... Over Specified Duty Cycles § 1065.550 Gas analyzer range validation, drift validation, and...

  18. The Genetic Drift Inventory: A Tool for Measuring What Advanced Undergraduates Have Mastered about Genetic Drift

    ERIC Educational Resources Information Center

    Price, Rebecca M.; Andrews, Tessa C.; McElhinny, Teresa L.; Mead, Louise S.; Abraham, Joel K.; Thanukos, Anna; Perez, Kathryn E.

    2014-01-01

    Understanding genetic drift is crucial for a comprehensive understanding of biology, yet it is difficult to learn because it combines the conceptual challenges of both evolution and randomness. To help assess strategies for teaching genetic drift, we have developed and evaluated the Genetic Drift Inventory (GeDI), a concept inventory that measures…

  19. Effect of drift control adjuvants on glyphosate spray drift and weed control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glyphosate drift on to off-target sensitive soybean may cause injury and reduce the yield. To solve this problem field experiment was conducted to determine the effect of drift control adjuvants (DCA) on downwind glyphosate drift and weed control in non-glyphosate-resistant soybean. The results show...

  20. Testing the Digital Divide: Does Access to High-Quality Use of Technology in Schools Affect Student Achievement?

    ERIC Educational Resources Information Center

    Talley, Gregory Keith

    2012-01-01

    This study investigates the relationship between access, use of technology and student achievement in public middle schools in Maryland. The objective of this study was to determine whether a digital divide (differences in access and utilization of technology based on student characteristics of race, socioeconomic status, and gender) exists among…

  1. Transient-induced climate drift

    SciTech Connect

    Johansson, A.; Reinhold, B.; Saha, S. )

    1993-05-01

    The climate drift of various quantities associated with deep, planetary-scale, equilibrated, transient Rossby waves are estimated for the Southern Hemisphere extratropical summer as revealed by the DERF II (Dynamical Extended Range Forecasting) dataset. It is found that the vertical structures of these waves systematically become too baroclinic during the course of integration. There are two time scales associated with this climate drift. There is one very short time scale, estimated to be of the order of one day, when the waves become more barotropic. It is followed by a period when the wave baroclinicity monotonically increases, and after roughly 10 days the model structures appear to have reached their statistically equilibrated state. In the meantime, the kinetic energy of the transient waves decreases substantially to roughly half the observed value. After this initial drop, however, the transient kinetic energy increases again, and it is not clear if an equilibrium value has been reached after 30 days, which is the limit of the DERF II dataset. This third time scale is not found in the quantities directly associated with the vertical structures per se, but it is hypothesized to be a consequence of these errors. A theory is utilized that in a simplified way takes into account the processes that determine the vertical structure of baroclinic waves as well as their robustness as a means of understanding the processes leading to these errors. The implications from this theory are that the formulation and magnitude of the dissipative and diffusive processes in the model are the most likely problem, but there are other possibilities. 37 refs., 10 figs.

  2. Intonation in unaccompanied singing: accuracy, drift, and a model of reference pitch memory.

    PubMed

    Mauch, Matthias; Frieler, Klaus; Dixon, Simon

    2014-07-01

    This paper presents a study on intonation and intonation drift in unaccompanied singing, and proposes a simple model of reference pitch memory that accounts for many of the effects observed. Singing experiments were conducted with 24 singers of varying ability under three conditions (Normal, Masked, Imagined). Over the duration of a recording, ∼50 s, a median absolute intonation drift of 11 cents was observed. While smaller than the median note error (19 cents), drift was significant in 22% of recordings. Drift magnitude did not correlate with other measures of singing accuracy, singing experience, or the presence of conditions tested. Furthermore, it is shown that neither a static intonation memory model nor a memoryless interval-based intonation model can account for the accuracy and drift behavior observed. The proposed causal model provides a better explanation as it treats the reference pitch as a changing latent variable. PMID:24993224

  3. Effect of unsteady wind on drifting snow

    NASA Astrophysics Data System (ADS)

    Cierco, F.-X.; Naaim-Bouvet, F.; Naaim, M.

    2003-04-01

    Wind is not always a steady flow. It can oscillate producing blasts. However most of the current numerical models of drifting snow are constrained by one major assumption : forcing winds are steady and uniform. Experiments done in the CSTB climatic wind tunnel (with a data acquisition frequency of 1 Hz both for wind and drifting snow) showed that drifting snow is in a state of permanent disequilibrium in the presence of fluctuating airflows : mass flux and velocity were poorly matched. However, the study of wind and drifting snow gust factors done at Col du Lac Blanc (parameters recorded every 15 min with a scan rate of 1 s) shown that the largest drifting snow episodes appear during periods of roughly constant strong wind whereas a short but strong blast does not produce significant drifting snow. In order to better understand the effect of unsteady wind on drifting snow processes, these first investigations have been completed during winter 2003 by increasing the acquisition frequency during snow storms at Col du Lac Blanc using an ultrasonic anemometer and a profile of six drifting snow acoustic sensors set up side by side.

  4. Banana drift transport in tokamaks with ripple

    SciTech Connect

    Linsker, R.; Boozer, A.H.

    1982-01-01

    Ripple transport in tokamaks is discussed for the ''banana drift'' collisionality regime, which lies below the ripple plateau regime treated earlier. The physical mechanisms that dominate banana drift transport are found to differ from those considered in previous work on this regime, and consequently the resulting transport coefficients can differ by several orders of magnitude.

  5. Banana drift transport in tokamaks with ripple

    SciTech Connect

    Linsker, R.; Boozer, A.H.

    1981-04-01

    Ripple transport in tokamaks is discussed for the banana drift collisionality regime, which lies below the ripple plateau regime treated earlier. The physical mechanisms that dominate banana drift transport are found to differ from those considered in previous work on this regime, and the resulting transport coefficients can consequently differ by several orders of magnitude.

  6. TBV-361 RESOLUTION ANALYSIS: EMPLACEMENT DRIFT ORIENTATION

    SciTech Connect

    M. Lin; D.C. Kicker; M.D. Sellers

    1999-07-17

    The purpose of this To Be Verified/To Be Determined (TBX) resolution analysis is to release ''To Be Verified'' (TBV)-361 related to the emplacement drift orientation. The system design criterion in ''Subsurface Facility System Description Document'' (CRWMS M&O 1998a, p.9) specifies that the emplacement drift orientation relative to the dominant joint orientations should be at least 30 degrees. The specific objectives for this analysis include the following: (1) Collect and evaluate key block data developed for the repository host horizon rock mass. (2) Assess the dominant joint orientations based on available fracture data. (3) Document the maximum block size as a function of drift orientation. (4) Assess the applicability of the drift orientation/joint orientation offset criterion in the ''Subsurface Facility System Description Document'' (CRWMS M&O 1998a, p.9). (5) Consider the effects of seepage on drift orientation. (6) Verify that the viability assessment (VA) drift orientation complies with the drift orientation/joint orientation offset criterion, or provide justifications and make recommendations for modifying the VA emplacement drift layout. In addition to providing direct support to the System Description Document (SDD), the release of TBV-361 will provide support to the Repository Subsurface Design Department. The results from this activity may also provide data and information needs to support the MGR Requirements Department, the MGR Safety Assurance Department, and the Performance Assessment Organization.

  7. Spray Drift Issues and Technologies for Mitigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Herbicide-induced plant damage due to off-target spray drift has become a major problem in some regions prompting States to take regulatory action regarding drift mitigation. For example, the Arkansas Plant Board has proposed new regulations regarding spray of Glyphosate and 2, 4-D. These regulation...

  8. Biology Undergraduates' Misconceptions about Genetic Drift

    ERIC Educational Resources Information Center

    Andrews, T. M.; Price, R. M.; Mead, L. S.; McElhinny, T. L.; Thanukos, A.; Perez, K. E.; Herreid, C. F.; Terry, D. R.; Lemons, P. P.

    2012-01-01

    This study explores biology undergraduates' misconceptions about genetic drift. We use qualitative and quantitative methods to describe students' definitions, identify common misconceptions, and examine differences before and after instruction on genetic drift. We identify and describe five overarching categories that include 16 distinct…

  9. Evaluation of realtime spray drift using RTDrift Gaussian advection-diffusion model.

    PubMed

    Lebeau, Frédéric; Verstraete, Arnaud; Schiffers, Bruno; Destain, Marie-France

    2009-01-01

    A spray drift model was developed to deliver real time information to the pesticide applicator. The sprayer is equipped with sensors to deliver real time measurement of operational parameters as spray pressure, boom height, horizontal boom movements and geolocalization. The spray droplet size spectrum as a function of pressure was characterized using PDI measurements. Wind speed and direction were measured using a sprayer mounted 2-D ultrasonic anemometer. For each successive boom position, a diffusion-advection Gaussian tilting plume model is used to compute the spray drift deposits downwind. Drift is computed independently for each droplet classes and each nozzle based on the operating parameters. Field trials were performed on a test plot in various wind conditions. The ground drift was measured for different drift distances using fluorimetry analysis. Results show that drift deposits are mainly affected by wind speed and direction what was correctly accounted for by the model. Short distance drift deposits values were overestimated by the model while long distance drift was underestimated. It appears that this most probably origins from embarked wind speed measurements and diffusion parameter. It is concluded that a treatment of embarked wind speed and diffusion measurement should be used to minimize these errors. PMID:20218507

  10. Eye-safe lidar system for pesticide spray drift measurement.

    PubMed

    Gregorio, Eduard; Rocadenbosch, Francesc; Sanz, Ricardo; Rosell-Polo, Joan R

    2015-01-01

    Spray drift is one of the main sources of pesticide contamination. For this reason, an accurate understanding of this phenomenon is necessary in order to limit its effects. Nowadays, spray drift is usually studied by using in situ collectors which only allow time-integrated sampling of specific points of the pesticide clouds. Previous research has demonstrated that the light detection and ranging (lidar) technique can be an alternative for spray drift monitoring. This technique enables remote measurement of pesticide clouds with high temporal and distance resolution. Despite these advantages, the fact that no lidar instrument suitable for such an application is presently available has appreciably limited its practical use. This work presents the first eye-safe lidar system specifically designed for the monitoring of pesticide clouds. Parameter design of this system is carried out via signal-to-noise ratio simulations. The instrument is based on a 3-mJ pulse-energy erbium-doped glass laser, an 80-mm diameter telescope, an APD optoelectronic receiver and optomechanically adjustable components. In first test measurements, the lidar system has been able to measure a topographic target located over 2 km away. The instrument has also been used in spray drift studies, demonstrating its capability to monitor the temporal and distance evolution of several pesticide clouds emitted by air-assisted sprayers at distances between 50 and 100 m. PMID:25658395

  11. Eye-Safe Lidar System for Pesticide Spray Drift Measurement

    PubMed Central

    Gregorio, Eduard; Rocadenbosch, Francesc; Sanz, Ricardo; Rosell-Polo, Joan R.

    2015-01-01

    Spray drift is one of the main sources of pesticide contamination. For this reason, an accurate understanding of this phenomenon is necessary in order to limit its effects. Nowadays, spray drift is usually studied by using in situ collectors which only allow time-integrated sampling of specific points of the pesticide clouds. Previous research has demonstrated that the light detection and ranging (lidar) technique can be an alternative for spray drift monitoring. This technique enables remote measurement of pesticide clouds with high temporal and distance resolution. Despite these advantages, the fact that no lidar instrument suitable for such an application is presently available has appreciably limited its practical use. This work presents the first eye-safe lidar system specifically designed for the monitoring of pesticide clouds. Parameter design of this system is carried out via signal-to-noise ratio simulations. The instrument is based on a 3-mJ pulse-energy erbium-doped glass laser, an 80-mm diameter telescope, an APD optoelectronic receiver and optomechanically adjustable components. In first test measurements, the lidar system has been able to measure a topographic target located over 2 km away. The instrument has also been used in spray drift studies, demonstrating its capability to monitor the temporal and distance evolution of several pesticide clouds emitted by air-assisted sprayers at distances between 50 and 100 m. PMID:25658395

  12. How Much Control Do Children and Adolescents Have over Genomic Testing, Parental Access to Their Results, and Parental Communication of Those Results to Others?

    PubMed

    Clayton, Ellen Wright

    2015-01-01

    Adolescents may often have opinions about whether they want genetic and genomic testing in both the clinic and research and about who should have access to the results. This legal analysis demonstrates that the law provides very little protection to minors' wishes. PMID:26479563

  13. Ground Control for Emplacement Drifts for LA

    SciTech Connect

    Y. Sun

    2004-07-09

    The purpose of this calculation is to analyze the stability of repository emplacement drifts during the preclosure period, and to provide a final ground support method for emplacement drifts for the License Application (LA). The scope of the work includes determination of input parameter values and loads, selection of appropriate process and methods for the calculation, application of selected methods, such as empirical or analytical, to the calculation, development and execution of numerical models, and evaluation of results. Results from this calculation are limited to use for design of the emplacement drifts and the final ground support system installed in these drifts. The design of non-emplacement openings and their ground support systems is covered in the ''Ground Control for Non-Emplacement Drifts for LA'' (BSC 2004c).

  14. Quantifying Particle Numbers and Mass Flux in Drifting Snow

    NASA Astrophysics Data System (ADS)

    Crivelli, Philip; Paterna, Enrico; Horender, Stefan; Lehning, Michael

    2016-06-01

    We compare two of the most common methods of quantifying mass flux, particle numbers and particle-size distribution for drifting snow events, the snow-particle counter (SPC), a laser-diode-based particle detector, and particle tracking velocimetry based on digital shadowgraphic imaging. The two methods were correlated for mass flux and particle number flux. For the SPC measurements, the device was calibrated by the manufacturer beforehand. The shadowgrapic imaging method measures particle size and velocity directly from consecutive images, and before each new test the image pixel length is newly calibrated. A calibration study with artificially scattered sand particles and glass beads provides suitable settings for the shadowgraphical imaging as well as obtaining a first correlation of the two methods in a controlled environment. In addition, using snow collected in trays during snowfall, several experiments were performed to observe drifting snow events in a cold wind tunnel. The results demonstrate a high correlation between the mass flux obtained for the calibration studies (r ≥slant 0.93 ) and good correlation for the drifting snow experiments (r ≥slant 0.81 ). The impact of measurement settings is discussed in order to reliably quantify particle numbers and mass flux in drifting snow. The study was designed and performed to optimize the settings of the digital shadowgraphic imaging system for both the acquisition and the processing of particles in a drifting snow event. Our results suggest that these optimal settings can be transferred to different imaging set-ups to investigate sediment transport processes.

  15. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    SciTech Connect

    P. Dixon

    2004-04-05

    The purpose of this Model Report (REV02) is to document the unsaturated zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrological-chemical (THC) processes on UZ flow and transport. This Model Report has been developed in accordance with the ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (Bechtel SAIC Company, LLC (BSC) 2002 [160819]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this Model Report in Section 1.12, Work Package AUZM08, ''Coupled Effects on Flow and Seepage''. The plan for validation of the models documented in this Model Report is given in Attachment I, Model Validation Plans, Section I-3-4, of the TWP. Except for variations in acceptance criteria (Section 4.2), there were no deviations from this TWP. This report was developed in accordance with AP-SIII.10Q, ''Models''. This Model Report documents the THC Seepage Model and the Drift Scale Test (DST) THC Model. The THC Seepage Model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral alteration on flow in rocks surrounding drifts. The DST THC model is a drift-scale process model relying on the same conceptual model and much of the same input data (i.e., physical, hydrological, thermodynamic, and kinetic) as the THC Seepage Model. The DST THC Model is the primary method for validating the THC Seepage Model. The DST THC Model compares predicted water and gas compositions, as well as mineral alteration patterns, with observed data from the DST. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal-loading conditions, and predict the evolution of mineral alteration and fluid chemistry around potential waste emplacement drifts. The DST THC Model is used solely for the validation of the THC

  16. The Silicon Drift Detector of the ALICE Experiment

    SciTech Connect

    Batigne, G.

    2005-10-12

    The ALICE experiment studies the properties of quark-gluon plasma and requires a good tracking system. This document presents the silicon drift detector which is part of the Inner Tracking System. Its principle and main features are given, especially its sensitivity to temperature variation and the effect of parasitic fields on measurement. Finally, the typical spatial resolution of this detector, which has been measured during beam tests, is shown.

  17. Drift Kinetic Theory and Cosmic Rays

    SciTech Connect

    Webb, G. M.; Le Roux, J. A.; Zank, G. P.

    2009-11-11

    Starting from the Vlasov or Boltzmann equation for cosmic rays in a random and regular magnetic field, we introduce guiding center coordinates and transform the velocity to a frame moving at the electric field drift velocity. The resultant equation is written in terms of the parallel and perpendicular momentum and gyro-phase of the particle, and describes spatial particle transport in guiding center coordinates. Using the drift ordering in which the gyro-scale and gyro-period are assumed short compared to the background flow length and time scales, and averaging over the gyro-phase gives the drift kinetic equation in which the adiabatic moment and total particle energy in the inertial frame are used to describe the momentum and energy of the particle. If the parallel electric field is small, the adiabatic moment of the particles is conserved to lowest order in the drift ordering. The resultant drift kinetic equation properly takes into account the energy changes of the particles due to drifts along the electric field, and betatron acceleration, but contains only the lowest order approximation for the guiding center drift velocity to describe the spatial advection of the particles. A further transformation of variables, in which the particle momentum and pitch angle are specified in the local fluid frame, gives the focussed transport equation derived by Skilling to describe particle transport in a moving plasma medium, such as the solar wind. The connections to previous derivations of the Skilling's pitch angle focussed transport equation are discussed.

  18. Seepage into drifts with mechanical degradation.

    PubMed

    Li, Guomin; Tsang, Chin-Fu

    2003-01-01

    Seepage into drifts in unsaturated tuff is an important issue for the long-term performance of the proposed nuclear waste repository at Yucca Mountain, Nevada. Drifts in which waste packages will be emplaced are subject to degradation in the form of rockfall from the drift ceiling, induced by stress-relief, seismic, or thermal effects. The objective of this study is to calculate seepage rates, for various drift-degradation scenarios and for different values of percolation flux, in the Topopah Spring middle nonlithophysal (Tptpmn) and the Topopah Spring lower lithophysal (Tptpll) units at Yucca Mountain. Seepage calculations are conducted by (1) defining a heterogeneous drift-scale permeability model with field data, (2) selecting calibrated parameters associated with the Tptpmn and Tptpll units, and (3) simulating seepage, based on detailed degraded-drift profiles obtained from a separate rock mechanics engineering analysis. The simulation results indicate (1) that the seepage threshold (i.e., the percolation flux at which seepage first occurs) is not significantly changed by drift degradation and (2) the degradation-induced increase in seepage above the threshold is influenced probably more by the shape of the cavity created by rockfall than by rockfall volume. PMID:12714289

  19. Drift Kinetic Theory and Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Webb, G. M.; Le Roux, J. A.; Zank, G. P.

    2009-11-01

    Starting from the Vlasov or Boltzmann equation for cosmic rays in a random and regular magnetic field, we introduce guiding center coordinates and transform the velocity to a frame moving at the electric field drift velocity. The resultant equation is written in terms of the parallel and perpendicular momentum and gyro-phase of the particle, and describes spatial particle transport in guiding center coordinates. Using the drift ordering in which the gyro-scale and gyro-period are assumed short compared to the background flow length and time scales, and averaging over the gyro-phase gives the drift kinetic equation in which the adiabatic moment and total particle energy in the inertial frame are used to describe the momentum and energy of the particle. If the parallel electric field is small, the adiabatic moment of the particles is conserved to lowest order in the drift ordering. The resultant drift kinetic equation properly takes into account the energy changes of the particles due to drifts along the electric field, and betatron acceleration, but contains only the lowest order approximation for the guiding center drift velocity to describe the spatial advection of the particles. A further transformation of variables, in which the particle momentum and pitch angle are specified in the local fluid frame, gives the focussed transport equation derived by Skilling [1] to describe particle transport in a moving plasma medium, such as the solar wind. The connections to previous derivations of the Skilling's pitch angle focussed transport equation are discussed.

  20. In-Drift Precipitates/Salts Model

    SciTech Connect

    P. Mariner

    2003-10-21

    As directed by ''Technical Work Plan For: Engineered Barrier System Department Modeling and Testing FY03 Work Activities'' (BSC 2003 [165601]), the In-Drift Precipitates/Salts (IDPS) model is developed and refined to predict the aqueous geochemical effects of evaporation in the proposed repository. The purpose of this work is to provide a model for describing and predicting the postclosure effects of evaporation and deliquescence on the chemical composition of water within the proposed Engineered Barrier System (EBS). Application of this model is to be documented elsewhere for the Total System Performance Assessment License Application (TSPA-LA). The principal application of this model is to be documented in REV 02 of ''Engineered Barrier System: Physical and Chemical Environment Model'' (BSC 2003 [165601]). The scope of this document is to develop, describe, and validate the IDPS model. This model is a quasi-equilibrium model. All reactions proceed to equilibrium except for several suppressed minerals in the thermodynamic database not expected to form under the proposed repository conditions within the modeling timeframe. In this revision, upgrades to the EQ3/6 code (Version 8.0) and Pitzer thermodynamic database improve the applicable range of the model. These new additions allow equilibrium and reaction-path modeling of evaporation to highly concentrated brines for potential water compositions of the system Na-K-H-Mg-Ca-Al-Cl-F-NO{sub 3}-SO{sub 4}-Br-CO{sub 3}-SiO{sub 2}-CO{sub 2}-O{sub 2}-H{sub 2}O at temperatures in the range of 0 C to 125 C, pressures in the atmospheric range, and relative humidity in the range of 0 to 100 percent. This system applies to oxidizing conditions only, and therefore limits the model to applications involving oxidizing conditions. A number of thermodynamic parameters in the Pitzer database have values that have not been determined or verified for the entire temperature range. In these cases, the known values are used to approximate

  1. Transient chaotic transport in dissipative drift motion

    NASA Astrophysics Data System (ADS)

    Oyarzabal, R. S.; Szezech, J. D.; Batista, A. M.; de Souza, S. L. T.; Caldas, I. L.; Viana, R. L.; Sanjuán, M. A. F.

    2016-04-01

    We investigate chaotic particle transport in magnetised plasmas with two electrostatic drift waves. Considering dissipation in the drift motion, we verify that the removed KAM surfaces originate periodic attractors with their corresponding basins of attraction. We show that the properties of the basins depend on the dissipation and the space-averaged escape time decays exponentially when the dissipation increases. We find positive finite time Lyapunov exponents in dissipative drift motion, consequently the trajectories exhibit transient chaotic transport. These features indicate how the transient plasma transport depends on the dissipation.

  2. Nonlinear Gyrokinetic Theory With Polarization Drift

    SciTech Connect

    L. Wang and T.S. Hahm

    2010-03-25

    A set of the electrostatic toroidal gyrokinetic Vlasov equation and the Poisson equation, which explicitly includes the polarization drift, is derived systematically by using Lie-transform method. The polarization drift is introduced in the gyrocenter equations of motion, and the corresponding polarization density is derived. Contrary to the wide-spread expectation, the inclusion of the polarization drift in the gyrocenter equations of motion does not affect the expression for the polarization density significantly. This is due to modification of the gyrocenter phase-space volume caused by the electrostatic potential [T. S. Hahm, Phys. Plasmas 3, 4658 (1996)] .

  3. Collisional Drift Waves in Stellarator Plasmas

    SciTech Connect

    J.L.V. Lewandowski

    2003-10-07

    A computational study of resistive drift waves in the edge plasma of a stellarator with an helical magnetic axis is presented. Three coupled field equations, describing the collisional drift wave dynamics in the linear approximation, are solved as an initial-value problem along the magnetic field line. The magnetohydrodynamic equilibrium is obtained from a three-dimensional local equilibrium model. The use of a local magnetohydrodynamic equilibrium model allows for a computationally efficient systematic study of the impact of the magnetic field structure on drift wave stability.

  4. 50 CFR 665.810 - Prohibition of drift gillnetting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES IN THE WESTERN PACIFIC Western Pacific Pelagic Fisheries § 665.810 Prohibition of drift gillnetting. Fishing with drift gillnets in...

  5. 50 CFR 665.810 - Prohibition of drift gillnetting.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES IN THE WESTERN PACIFIC Western Pacific Pelagic Fisheries § 665.810 Prohibition of drift gillnetting. Fishing with drift gillnets in...

  6. 50 CFR 665.810 - Prohibition of drift gillnetting.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES IN THE WESTERN PACIFIC Western Pacific Pelagic Fisheries § 665.810 Prohibition of drift gillnetting. Fishing with drift gillnets in...

  7. 50 CFR 665.810 - Prohibition of drift gillnetting.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES IN THE WESTERN PACIFIC Western Pacific Pelagic Fisheries § 665.810 Prohibition of drift gillnetting. Fishing with drift gillnets in...

  8. Testing the Coulomb/Accessible Surface Area solvent model for protein stability, ligand binding, and protein design

    PubMed Central

    am Busch, Marcel Schmidt; Lopes, Anne; Amara, Najette; Bathelt, Christine; Simonson, Thomas

    2008-01-01

    Background Protein structure prediction and computational protein design require efficient yet sufficiently accurate descriptions of aqueous solvent. We continue to evaluate the performance of the Coulomb/Accessible Surface Area (CASA) implicit solvent model, in combination with the Charmm19 molecular mechanics force field. We test a set of model parameters optimized earlier, and we also carry out a new optimization in this work, using as a target a set of experimental stability changes for single point mutations of various proteins and peptides. The optimization procedure is general, and could be used with other force fields. The computation of stability changes requires a model for the unfolded state of the protein. In our approach, this state is represented by tripeptide structures of the sequence Ala-X-Ala for each amino acid type X. We followed an iterative optimization scheme which, at each cycle, optimizes the solvation parameters and a set of tripeptide structures for the unfolded state. This protocol uses a set of 140 experimental stability mutations and a large set of tripeptide conformations to find the best tripeptide structures and solvation parameters. Results Using the optimized parameters, we obtain a mean unsigned error of 2.28 kcal/mol for the stability mutations. The performance of the CASA model is assessed by two further applications: (i) calculation of protein-ligand binding affinities and (ii) computational protein design. For these two applications, the previous parameters and the ones optimized here give a similar performance. For ligand binding, we obtain reasonable agreement with a set of 55 experimental mutation data, with a mean unsigned error of 1.76 kcal/mol with the new parameters and 1.47 kcal/mol with the earlier ones. We show that the optimized CASA model is not inferior to the Generalized Born/Surface Area (GB/SA) model for the prediction of these binding affinities. Likewise, the new parameters perform well for the design of 8

  9. HIV testing and preventive services accessibility among men who have sex with men at high risk of HIV infection in Beijing, China.

    PubMed

    Zhao, Yuejuan; Zhang, Li; Zhang, Heng; Xia, Dongyan; Pan, Stephen W; Yue, Hai; Lu, Hongyan; Xing, Hui; He, Xiong; Shao, Yiming; Ruan, Yuhua

    2015-02-01

    The HIV epidemic among men who have sex with men (MSM) has been increasing at an alarming rate in most areas of China in recent years. Many Chinese MSM still lack sufficient access to HIV prevention services, despite ongoing scale-up of comprehensive HIV testing and intervention services. The purpose of this study was to investigate utilization of HIV testing and prevention services, and related factors that influence the MSM people to access HIV test or other services to prevent HIV among MSM in Beijing, China.Three successive cross-sectional surveys of MSM were conducted in Beijing from September 2009 to January 2010, September 2010 to January 2011, and September 2011 to January 2012. Demographic and behavioral data were collected and analyzed. Blood samples were tested for HIV and syphilis. Three models were established to analyze factors associated with HIV testing and preventive services.Of the 1312 participants, prevalence of HIV and syphilis was 7.9% and 15.4%, respectively. Sixty-nine percent ever had an HIV test, 56.2%, 78.7%, and 46.1% received HIV test, free condom/lubricants, and sexually transmitted infection services in the past 12 months (P12M), respectively. MSM with larger social networks and who knew someone infected with HIV were more likely to receive HIV testing and preventive services; lower degrees of stigma and discriminatory attitudes toward HIV/AIDS were positively associated with having an HIV test, whereas unprotected anal intercourse in the past 6 months (P6M) was associated with less preventive services participation. The most reported barriers to HIV testing were fear of testing HIV positive (79.3%) and perceiving no risk for HIV (75.4%). Almost all participants felt that ensuring confidentiality would encourage more MSM to have an HIV test. The two main reasons for not seeking HIV test was not knowing where to go for a test (63.2%) and perceiving low risk of HIV infection (55.1%).Given a high prevalence of HIV, syphilis, and risky

  10. HIV Testing and Preventive Services Accessibility Among Men Who Have Sex With Men at High Risk of HIV Infection in Beijing, China

    PubMed Central

    Zhao, Yuejuan; Zhang, Li; Zhang, Heng; Xia, Dongyan; Pan, Stephen W.; Yue, Hai; Lu, Hongyan; Xing, Hui; He, Xiong; Shao, Yiming; Ruan, Yuhua

    2015-01-01

    Abstract The HIV epidemic among men who have sex with men (MSM) has been increasing at an alarming rate in most areas of China in recent years. Many Chinese MSM still lack sufficient access to HIV prevention services, despite ongoing scale-up of comprehensive HIV testing and intervention services. The purpose of this study was to investigate utilization of HIV testing and prevention services, and related factors that influence the MSM people to access HIV test or other services to prevent HIV among MSM in Beijing, China. Three successive cross-sectional surveys of MSM were conducted in Beijing from September 2009 to January 2010, September 2010 to January 2011, and September 2011 to January 2012. Demographic and behavioral data were collected and analyzed. Blood samples were tested for HIV and syphilis. Three models were established to analyze factors associated with HIV testing and preventive services. Of the 1312 participants, prevalence of HIV and syphilis was 7.9% and 15.4%, respectively. Sixty-nine percent ever had an HIV test, 56.2%, 78.7%, and 46.1% received HIV test, free condom/lubricants, and sexually transmitted infection services in the past 12 months (P12M), respectively. MSM with larger social networks and who knew someone infected with HIV were more likely to receive HIV testing and preventive services; lower degrees of stigma and discriminatory attitudes toward HIV/AIDS were positively associated with having an HIV test, whereas unprotected anal intercourse in the past 6 months (P6M) was associated with less preventive services participation. The most reported barriers to HIV testing were fear of testing HIV positive (79.3%) and perceiving no risk for HIV (75.4%). Almost all participants felt that ensuring confidentiality would encourage more MSM to have an HIV test. The two main reasons for not seeking HIV test was not knowing where to go for a test (63.2%) and perceiving low risk of HIV infection (55.1%). Given a high prevalence of HIV, syphilis

  11. Drift in interference filters. 2: radiation effects.

    PubMed

    Title, A M

    1974-11-01

    Studies of peak transmission drift in narrow-band interference filters have shown that there exist two mechanisms that cause drift toward shorter wavelengths. One is dependent on the thermal history of the filter and is discussed in Part 1 of this paper. The other is dependent on the exposure of the filter to radiation. For ZnS-cryolite filters of the design [(HL)(4)H(8)(LH)(4)L](3)L(-1), it is experimentally demonstrated that the filters are most sensitive to radiation in a 100-A band centered at approximately 3900 A. The drift rate in the focal plane of an f/20 solar image is approximately 3 A/100 h of exposure. Further, it is also shown by model calculations that the observed radiation-induced drift is consistent with the hypothesis that the optical thickness of ZnS decreases in proportion to the radiant energy absorbed. PMID:20134754

  12. CROSS DRIFT ALCOVE/NICHE UTILITIES ANALYSIS

    SciTech Connect

    S. Goodin

    1999-07-08

    The purpose of this analysis is to provide the design basis and general arrangement requirements of the non-potable water, waste water, compressed air and ventilation (post excavation) utilities required in support of the Cross Drift alcoves and niches.

  13. Drift Wave Turbulence and Magnetic Reconnection

    NASA Astrophysics Data System (ADS)

    Price, L.; Drake, J. F.; Swisdak, M.

    2015-12-01

    An important feature in collisionless magnetic reconnection is the development of sharp discontinuities along the separatrices bounding the Alfvenic outflow. The typical scale length of these features is ρs (the Larmor radius based on the sound speed) for guide field reconnection. Temperature gradients in the inflowing plasma (as might be found in the magnetopause and the magnetotail) can lead to instabilities at these separatrices, specifically drift wave turbulence. We present standalone 2D and 3D PIC simulations of drift wave turbulence to investigate scaling properties and growth rates. We specifically consider stabilization of the lower hybrid drift instability (LHDI) and the development of this instability in the presence of a sheared magnetic field. Further investigations of the relative importance of drift wave turbulence in the development of reconnection will also be considered.

  14. On the electron drift velocity in plasma devices with E × B drift

    NASA Astrophysics Data System (ADS)

    Chapurin, O.; Smolyakov, A.

    2016-06-01

    The structure and various components of the electron drift velocity are discussed in application to plasma discharges with the E × B drift. In high density plasmas, the contribution of the diamagnetic drift can be of the same order magnitude as the E × B drift. It is pointed out that curvature and gradient drifts associated with magnetic field inhomogeneities manifest themselves via the electron pressure anisotropy. Estimates show that the components of the diamagnetic drift related to the electron pressure anisotropy and magnetic field gradients can be important for the parameters of modern magnetrons and Hall thrusters. Similar additional terms appear in the momentum balance as mirror forces which may affect the distribution of the electrostatic potential in Hall devices.

  15. Self-shielding flex-circuit drift tube, drift tube assembly and method of making

    DOEpatents

    Jones, David Alexander

    2016-04-26

    The present disclosure is directed to an ion mobility drift tube fabricated using flex-circuit technology in which every other drift electrode is on a different layer of the flex-circuit and each drift electrode partially overlaps the adjacent electrodes on the other layer. This results in a self-shielding effect where the drift electrodes themselves shield the interior of the drift tube from unwanted electro-magnetic noise. In addition, this drift tube can be manufactured with an integral flex-heater for temperature control. This design will significantly improve the noise immunity, size, weight, and power requirements of hand-held ion mobility systems such as those used for explosive detection.

  16. Effects of Fault Displacement on Emplacement Drifts

    SciTech Connect

    F. Duan

    2000-04-25

    The purpose of this analysis is to evaluate potential effects of fault displacement on emplacement drifts, including drip shields and waste packages emplaced in emplacement drifts. The output from this analysis not only provides data for the evaluation of long-term drift stability but also supports the Engineered Barrier System (EBS) process model report (PMR) and Disruptive Events Report currently under development. The primary scope of this analysis includes (1) examining fault displacement effects in terms of induced stresses and displacements in the rock mass surrounding an emplacement drift and (2 ) predicting fault displacement effects on the drip shield and waste package. The magnitude of the fault displacement analyzed in this analysis bounds the mean fault displacement corresponding to an annual frequency of exceedance of 10{sup -5} adopted for the preclosure period of the repository and also supports the postclosure performance assessment. This analysis is performed following the development plan prepared for analyzing effects of fault displacement on emplacement drifts (CRWMS M&O 2000). The analysis will begin with the identification and preparation of requirements, criteria, and inputs. A literature survey on accommodating fault displacements encountered in underground structures such as buried oil and gas pipelines will be conducted. For a given fault displacement, the least favorable scenario in term of the spatial relation of a fault to an emplacement drift is chosen, and the analysis is then performed analytically. Based on the analysis results, conclusions are made regarding the effects and consequences of fault displacement on emplacement drifts. Specifically, the analysis will discuss loads which can be induced by fault displacement on emplacement drifts, drip shield and/or waste packages during the time period of postclosure.

  17. Drift of dislocation tripoles under ultrasound influence.

    PubMed

    Murzaev, R T; Bachurin, D V; Nazarov, A A

    2016-01-01

    Numerical simulations of dynamics of different stable dislocation tripoles under influence of monochromatic standing sound wave were performed. The basic conditions necessary for the drift and mutual rearrangements between dislocation structures were investigated. The dependence of the drift velocity of the dislocation tripoles as a function of the frequency and amplitude of the external influence was obtained. The results of the work can be useful in analysis of motion and self-organization of dislocation structure under ultrasound influence. PMID:26278625

  18. SEEPAGE MODEL FOR PA INCLUDING DRIFT COLLAPSE

    SciTech Connect

    C. Tsang

    2004-09-22

    The purpose of this report is to document the predictions and analyses performed using the seepage model for performance assessment (SMPA) for both the Topopah Spring middle nonlithophysal (Tptpmn) and lower lithophysal (Tptpll) lithostratigraphic units at Yucca Mountain, Nevada. Look-up tables of seepage flow rates into a drift (and their uncertainty) are generated by performing numerical simulations with the seepage model for many combinations of the three most important seepage-relevant parameters: the fracture permeability, the capillary-strength parameter 1/a, and the percolation flux. The percolation flux values chosen take into account flow focusing effects, which are evaluated based on a flow-focusing model. Moreover, multiple realizations of the underlying stochastic permeability field are conducted. Selected sensitivity studies are performed, including the effects of an alternative drift geometry representing a partially collapsed drift from an independent drift-degradation analysis (BSC 2004 [DIRS 166107]). The intended purpose of the seepage model is to provide results of drift-scale seepage rates under a series of parameters and scenarios in support of the Total System Performance Assessment for License Application (TSPA-LA). The SMPA is intended for the evaluation of drift-scale seepage rates under the full range of parameter values for three parameters found to be key (fracture permeability, the van Genuchten 1/a parameter, and percolation flux) and drift degradation shape scenarios in support of the TSPA-LA during the period of compliance for postclosure performance [Technical Work Plan for: Performance Assessment Unsaturated Zone (BSC 2002 [DIRS 160819], Section I-4-2-1)]. The flow-focusing model in the Topopah Spring welded (TSw) unit is intended to provide an estimate of flow focusing factors (FFFs) that (1) bridge the gap between the mountain-scale and drift-scale models, and (2) account for variability in local percolation flux due to

  19. Strange Attractors in Drift Wave Turbulence

    SciTech Connect

    J.L.V. Lewandowski

    2003-04-25

    A multi-grid part-in-cell algorithm for a shearless slab drift wave model with kinetic electrons is presented. The algorithm, which is based on an exact separation of adiabatic and nonadiabatic electron responses, is used to investigate the presence of strange attractors in drift wave turbulence. Although the simulation model has a large number of degrees of freedom, it is found that the strange attractor is low-dimensional and that it is strongly affected by dissipative (collisional) effects.

  20. Web Site Usability Testing Involving People with Learning Disabilities Using Only Images and Audio to Access Information

    ERIC Educational Resources Information Center

    Williams, Peter

    2013-01-01

    The need for social inclusion, informed choice and the facilitation of independent living for people with learning disabilities (LD) is being emphasised ever more by government, professionals, academics and, indeed, by people with LD themselves, particularly in self-advocacy groups. Achieving goals around inclusion and autonomy requires access to…

  1. Confronting the "Acid Test": Educators' Perspectives on Expanding Access to Advanced Placement at a Diverse Florida High School

    ERIC Educational Resources Information Center

    Rowland, M. Lance; Shircliffe, Barbara J.

    2016-01-01

    This study examines educators' perspectives on accountability mandates designed to expand access to the College Board's Advanced Placement (AP) classes to traditionally underserved students at a diverse suburban high school in Florida, Palm Crest High School. Consistent with Elmore (1979), district and site-based administrators focused on the…

  2. Continuously live image processor for drift chamber track segment triggering

    SciTech Connect

    Berenyi, A.; Chen, H.K.; Dao, K.

    1999-06-01

    The first portion of the BaBar experiment Level 1 Drift Chamber Trigger pipeline is the Track Segment Finder (TSF). Using a novel method incorporating both occupancy and drift-time information, the TSF system continually searches for segments in the supercells of the full 7104-wire Drift Chamber hit image at 3.7 MHz. The TSF was constructed to operate in a potentially high beam-background environment while achieving high segment-finding efficiency, deadtime-free operation, a spatial resolution of <0.7 mm and a per-segment event time resolution of <70 ns. The TSF system consists of 24 hardware-identical TSF modules. These are the most complex modules in the BaBar trigger. On each module, fully parallel segment finding proceeds in 20 pipeline steps. Each module consists of a 9U algorithm board and a 6U interface board. The 9U printed circuit board has 10 layers and contains 0.9 million gates implemented in 25 FPGAs, which were synthesized from a total of 50,000 lines of VHDL. The boards were designed from the top-down with state-of-the-art CAD tools, which included gate-level board simulation. This methodology enabled production of a flawless board with no intermediate prototypes. It was fully tested with basic test patterns and 10{sup 5} simulated physics events.

  3. Shock drift acceleration in the presence of waves

    NASA Technical Reports Server (NTRS)

    Decker, R. B.; Vlahos, L.

    1985-01-01

    Attention is given to the initial results of a model designed to study the modification of the scatter-free, shock drift acceleration of energetic test particles by wave activity in the vicinity of a quasi-perpendicular, fast-mode MHD shock. It is emphasized that the concept of magnetic moment conservation is a valid approximation only in the perpendicular and nearly perpendicular regimes, when the angle theta-Bn between the shock normal and the upstream magnetic field vector is in the range from 70 deg to 90 deg. The present investigation is concerned with one step in a program which is being developed to combine the shock drift and diffusive processes at a shock of arbitrary theta-Bn.

  4. Modelling of the space-to-drift-time relationship of the ATLAS monitored drift-tube chambers in the presence of magnetic fields

    NASA Astrophysics Data System (ADS)

    Dubbert, J.; Horvat, S.; Khartchenko, D.; Kortner, O.; Kotov, S.; Kroha, H.; Manz, A.; Nikolaev, K.; Rauscher, F.; Richter, R.; Staude, A.; Valderanis, Ch.

    2007-03-01

    The ATLAS muon spectrometer uses tracking chambers consisting of up to 5 m long drift tubes filled with Ar:CO2(93:7) at 3 bar. The chambers are run in a average toroidal magnetic field of 0.4 T created by 8 air core coils. They provide a track-point accuracy of 40 μm if the space-to-drift-time relationship r(t) is known with 20 μm accuracy. The magnetic field B influences the electron drift inside the tubes: the maximum drift time tmax=700 ns increases by ≈70 ns/T2B2. B varies by up to ±0.4 T along the tubes of the chambers mounted near the magnet coils which translates into a variation of tmax of up to 45 ns. The dependence of r(t) on B must be taken into account. Test-beam measurements show that the electron drift in case of B≠0 can be modelled with the required accuracy by a Langevin equation with a friction term which is slightly non-linear in the drift velocity.

  5. Risk evaluation of drift from 40 aerially-applied herbicides on fish production pond plankton and water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Row crop herbicides were tested for possible adverse effects on pond plankton and water quality in triplicate 500-L outdoor, pool mesocosms. Treatments were drift at low (1% of full field rates) and high levels (10% of the full rate) to production ponds of 5 ha and large, and no drift (control). H...

  6. Daytime three-dimensional drifts at Millstone Hill Observatory. [F region drift from radar measurement

    NASA Technical Reports Server (NTRS)

    Carpenter, L. A.; Kirchhoff, V. W. J. H.

    1974-01-01

    Vertical drift measurements in the topside F region at midlatitudes have confirmed the importance of dynamical processes, but it has been difficult isolating those processes due to E X B drifts from those due to neutral winds. To remove this ambiguity, three-dimensional drift measurements were made at Millstone Hill Observatory with the steerable L-band radar in conjunction with the vertical UHF antenna. The geometry of the experiment is discussed and daytime drifts are presented. Unusual lifting of the F-layer peak was observed on two occasions. A reversal in the deduced meridional neutral wind is observed in one case and an enhanced eastward electric field in the other.

  7. The Legal Past, Present and Future of Prenatal Genetic Testing: Professional Liability and Other Legal Challenges Affecting Patient Access to Services

    PubMed Central

    Pergament, Deborah; Ilijic, Katie

    2014-01-01

    This chapter is an overview of the current status of the law in the United States regarding prenatal genetic testing with an emphasis on issues related to professional liability and other challenges affecting patient access to prenatal genetic testing. The chapter discusses the roles that federal regulations, promulgated by the Centers for Medicare and Medicaid Services (CMS), the Food and Drug Administration (FDA) and the Federal Trade Commission (FTC), play in the regulation of prenatal genetic tests. The chapter discusses tort litigation based on allegations of malpractice in the provision of prenatal genetic testing and how courts have analyzed issues related to causation, damages and mitigation of damages. The chapter provides reference information regarding how individual states address causes of action under the tort theories of wrongful birth and wrongful life. The chapter concludes with a discussion of future legal issues that may affect clinical prenatal genetic testing services arising from the continued expansion of prenatal genetic testing, legal restrictions on access to abortion and the potential development of embryonic treatments. PMID:26237611

  8. The Legal Past, Present and Future of Prenatal Genetic Testing: Professional Liability and Other Legal Challenges Affecting Patient Access to Services.

    PubMed

    Pergament, Deborah; Ilijic, Katie

    2014-01-01

    This chapter is an overview of the current status of the law in the United States regarding prenatal genetic testing with an emphasis on issues related to professional liability and other challenges affecting patient access to prenatal genetic testing. The chapter discusses the roles that federal regulations, promulgated by the Centers for Medicare and Medicaid Services (CMS), the Food and Drug Administration (FDA) and the Federal Trade Commission (FTC), play in the regulation of prenatal genetic tests. The chapter discusses tort litigation based on allegations of malpractice in the provision of prenatal genetic testing and how courts have analyzed issues related to causation, damages and mitigation of damages. The chapter provides reference information regarding how individual states address causes of action under the tort theories of wrongful birth and wrongful life. The chapter concludes with a discussion of future legal issues that may affect clinical prenatal genetic testing services arising from the continued expansion of prenatal genetic testing, legal restrictions on access to abortion and the potential development of embryonic treatments. PMID:26237611

  9. Advanced AEM by Comprehensive Analysis and Modeling of System Drift

    NASA Astrophysics Data System (ADS)

    Schiller, Arnulf; Klune, Klaus; Schattauer, Ingrid

    2010-05-01

    The quality of the assessment of risks outgoing from environmental hazards strongly depends on the spatial and temporal distribution of the data collected in a survey area. Natural hazards generally emerge from wide areas as it is in the case of volcanoes or land slides. Conventional surface measurements are restricted to few lines or locations and often can't be conducted in difficult terrain. So they only give a spatial and temporary limited data set and therefore limit the reliability of risk analysis. Aero-geophysical measurements potentially provide a valuable tool for completing the data set as they can be performed over a wide area, even above difficult terrain within a short time. A most desirable opportunity in course of such measurements is the ascertainment of the dynamics of such potentially hazardous environmental processes. This necessitates repeated and reproducible measurements. Current HEM systems can't accomplish this adequately due to their system immanent drift and - in some cases - bad signal to noise ratio. So, to develop comprising concepts for advancing state of the art HEM-systems to a valuable tool for data acquisition in risk assessment or hydrological problems, different studies have been undertaken which form the contents of the presented work conducted in course of the project HIRISK (Helicopter Based Electromagnetic System for Advanced Environmental Risk Assessment - FWF L-354 N10, supported by the Austrian Science Fund). The methodology is based upon two paths: A - Comprehensive experimental testing on an existing HEM system serving as an experimental platform. B - The setup of a numerical model which is continuously refined according to the results of the experimental data. The model then serves to simulate the experimental as well as alternative configurations and to analyze them subject to their drift behavior. Finally, concepts for minimizing the drift are derived and tested. Different test series - stationary on ground as well

  10. Wind selectivity and partial compensation for wind drift among nocturnally migrating passerines

    PubMed Central

    McLaren, James D.

    2012-01-01

    A migrating bird’s response to wind can impact its timing, energy expenditure, and path taken. The extent to which nocturnal migrants select departure nights based on wind (wind selectivity) and compensate for wind drift remains unclear. In this paper, we determine the effect of wind selectivity and partial drift compensation on the probability of successfully arriving at a destination area and on overall migration speed. To do so, we developed an individual-based model (IBM) to simulate full drift and partial compensation migration of juvenile Willow Warblers (Phylloscopus trochilus) along the southwesterly (SW) European migration corridor to the Iberian coast. Various degrees of wind selectivity were tested according to how large a drift angle and transport cost (mechanical energy per unit distance) individuals were willing to tolerate on departure after dusk. In order to assess model results, we used radar measurements of nocturnal migration to estimate the wind selectivity and proportional drift among passerines flying in SW directions. Migration speeds in the IBM were highest for partial compensation populations tolerating at least 25% extra transport cost compared to windless conditions, which allowed more frequent departure opportunities. Drift tolerance affected migration speeds only weakly, whereas arrival probabilities were highest with drift tolerances below 20°. The radar measurements were indicative of low drift tolerance, 25% extra transport cost tolerance and partial compensation. We conclude that along migration corridors with generally nonsupportive winds, juvenile passerines should not strictly select supportive winds but partially compensate for drift to increase their chances for timely and accurate arrival. PMID:22936843

  11. Mesh-size effects on drift sample composition as determined with a triple net sampler

    USGS Publications Warehouse

    Slack, K.V.; Tilley, L.J.; Kennelly, S.S.

    1991-01-01

    Nested nets of three different mesh apertures were used to study mesh-size effects on drift collected in a small mountain stream. The innermost, middle, and outermost nets had, respectively, 425 ??m, 209 ??m and 106 ??m openings, a design that reduced clogging while partitioning collections into three size groups. The open area of mesh in each net, from largest to smallest mesh opening, was 3.7, 5.7 and 8.0 times the area of the net mouth. Volumes of filtered water were determined with a flowmeter. The results are expressed as (1) drift retained by each net, (2) drift that would have been collected by a single net of given mesh size, and (3) the percentage of total drift (the sum of the catches from all three nets) that passed through the 425 ??m and 209 ??m nets. During a two day period in August 1986, Chironomidae larvae were dominant numerically in all 209 ??m and 106 ??m samples and midday 425 ??m samples. Large drifters (Ephemerellidae) occurred only in 425 ??m or 209 ??m nets, but the general pattern was an increase in abundance and number of taxa with decreasing mesh size. Relatively more individuals occurred in the larger mesh nets at night than during the day. The two larger mesh sizes retained 70% of the total sediment/detritus in the drift collections, and this decreased the rate of clogging of the 106 ??m net. If an objective of a sampling program is to compare drift density or drift rate between areas or sampling dates, the same mesh size should be used for all sample collection and processing. The mesh aperture used for drift collection should retain all species and life stages of significance in a study. The nested net design enables an investigator to test the adequacy of drift samples. ?? 1991 Kluwer Academic Publishers.

  12. WINCS v.2 for the Neutral Wind and Ion-drift in the Thermosphere/Ionosphere

    NASA Astrophysics Data System (ADS)

    Herrero, F. A.; Nicholas, A. C.

    2013-12-01

    The Wind Ion-drift Neutral Composition Suite (WINCS) has been updated to increase sensitivity to wind/ion-drift change and to further reduce risk and cost. Description of the new neutral wind/ion-drift spectrometer component of WINCS will be given with data results from simulations and laboratory tests of WINCS version 2. A 20-fold increase in wind/ion-drift sensitivity brings their uncertainties to about × 0.5 m/s; corresponding to a pointing uncertainty of × 0.005°. This precision improves accuracy in the wind/ion-drift when used with new star cameras that provide ×0.005° or better pointing accuracy; thus allowing vertical wind and vertical ion-drift measurements over broad regions of the upper atmosphere. The new design uses a larger aperture (0.1cm diameter instead of the 0.02cm diameter of WINCS v.1), and replaces the energy-scanning energy analyzer with a 30° PPA (parallel plate analyzer) energy spectrograph that simultaneously measures all energies of interest. These two features increase the signal to enable the new wind/ion-drift precisions stated above. Risk and cost reduction follow from the new electro-mechanical format that combines spectrometer mechanical mounting with the actual electrical connection. The presentation will close with discussion of cross-track and in-track wind and ion-drift components to emphasize the requirement of the energy analyzer in obtaining the magnitude of the total velocity in both cross-track and in-track winds and ion-drifts - that is, the total velocity of the neutrals or ions incident upon WINCS.

  13. 40 CFR 158.1100 - Spray drift data requirements table.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Spray drift data requirements table...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Spray Drift § 158.1100 Spray drift data requirements... spray drift data requirements for a particular pesticide product. Notes that apply to an individual...

  14. 40 CFR 158.1100 - Spray drift data requirements table.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Spray drift data requirements table...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Spray Drift § 158.1100 Spray drift data requirements... spray drift data requirements for a particular pesticide product. Notes that apply to an individual...

  15. 40 CFR 158.1100 - Spray drift data requirements table.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Spray drift data requirements table...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Spray Drift § 158.1100 Spray drift data requirements... spray drift data requirements for a particular pesticide product. Notes that apply to an individual...

  16. Field scale evaluation of spray drift reduction technologies from ground and aerial application systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this work is to evaluate a proposed Test Plan for the validation testing of pesticide spray drift reduction technologies for row and field crops, focusing on the testing of ground and aerial application systems under full-scale field evaluations. The measure of performance for a gi...

  17. Large-scale drift and Rossby wave turbulence

    NASA Astrophysics Data System (ADS)

    Harper, K. L.; Nazarenko, S. V.

    2016-08-01

    We study drift/Rossby wave turbulence described by the large-scale limit of the Charney–Hasegawa–Mima equation. We define the zonal and meridional regions as Z:= \\{{k} :| {k}y| \\gt \\sqrt{3}{k}x\\} and M:= \\{{k} :| {k}y| \\lt \\sqrt{3}{k}x\\} respectively, where {k}=({k}x,{k}y) is in a plane perpendicular to the magnetic field such that k x is along the isopycnals and k y is along the plasma density gradient. We prove that the only types of resonant triads allowed are M≤ftrightarrow M+Z and Z≤ftrightarrow Z+Z. Therefore, if the spectrum of weak large-scale drift/Rossby turbulence is initially in Z it will remain in Z indefinitely. We present a generalised Fjørtoft’s argument to find transfer directions for the quadratic invariants in the two-dimensional {k}-space. Using direct numerical simulations, we test and confirm our theoretical predictions for weak large-scale drift/Rossby turbulence, and establish qualitative differences with cases when turbulence is strong. We demonstrate that the qualitative features of the large-scale limit survive when the typical turbulent scale is only moderately greater than the Larmor/Rossby radius.

  18. Redshift drift in axially symmetric quasispherical Szekeres models

    NASA Astrophysics Data System (ADS)

    Mishra, Priti; Célérier, Marie-Noëlle; Singh, Tejinder P.

    2012-10-01

    Models of inhomogeneous universes constructed with exact solutions of Einstein’s general relativity have been proposed in the literature with the aim of reproducing the cosmological data without any need for a dark energy component. Besides large scale inhomogeneity models spherically symmetric around the observer, Swiss-cheese models have also been studied. Among them, Swiss cheeses where the inhomogeneous patches are modeled by different particular Szekeres solutions have been used for reproducing the apparent dimming of the type Ia supernovae. However, the problem of fitting such models to the type Ia supernovae data is completely degenerate and we need other constraints to fully characterize them. One of the tests which is known to be able to discriminate between different cosmological models is the redshift drift. This drift has already been calculated by different authors for Lemaître-Tolman-Bondi models. We compute it here for one particular axially symmetric quasispherical Szekeres Swiss cheese which has previously been shown to reproduce to a good accuracy the type Ia supernovae data, and we compare the results to the drift in the ΛCDM model and in some Lemaître-Tolman-Bondi models that can be found in the literature. We show that it is a good discriminator between them. Then, we discuss our model’s remaining degrees of freedom and propose a recipe to fully constrain them.

  19. Measurements verifying the optics of the Electron Drift Instrument

    NASA Astrophysics Data System (ADS)

    Kooi, Vanessa M.

    This thesis concentrates on laboratory measurements of the Electron Drift Instrument (EDI), focussing primarily on the EDI optics of the system. The EDI is a device used on spacecraft to measure electric fields by emitting an electron beam and measuring the E x B drift of the returning electrons after one gyration. This drift velocity is determined using two electron beams directed perpendicular to the magnetic field returning to be detected by the spacecraft. The EDI will be used on the Magnetospheric Multi-Scale Mission. The EDI optic's testing process takes measurements of the optics response to a uni-directional electron beam. These measurements are used to verify the response of the EDI's optics and to allow for the optimization of the desired optics state via simulation. The optics state tables were created in simulations and we are using these measurements to confirm their accuracy. The setup consisted of an apparatus made up of the EDI's optics and sensor electronics was secured to the two axis gear arm inside a vacuum chamber. An electron beam was projected at the apparatus which then used the EDI optics to focus the beam into the micro-controller plates and onto the circular 32 pad annular ring that makes up the sensor. The concentration of counts per pad over an interval of 1ms were averaged over 25 samples and plotted in MATLAB. The results of the measurements plotted agreed well with the simulations, providing confidence in the EDI instrument.

  20. STATUS OF THE NEUTRALIZED DRIFT COMPRESSION EXPERIMENT (NDCX-II)

    SciTech Connect

    Waldron, W.L.; Kwan, J.W.

    2011-04-21

    The Neutralized Drift Compression Experiment (NDCX-II) is an 11 M$ induction accelerator project currently in construction at Lawrence Berkeley National Laboratory for warm dense matter (WDM) experiments investigating the interaction of ion beams with matter at elevated temperature and pressure. The machine consists of a lithium injector, induction accelerator cells, diagnostic cells, a neutralized drift compression line, a final focus solenoid, and a target chamber. The induction cells and some of the pulsed power systems have been reused from the decommissioned Advanced Test Accelerator at Lawrence Livermore National Laboratory after refurbishment and modification. The machine relies on a sequence of acceleration waveforms to longitudinally compress the initial ion pulse from 600 ns to less than 1 ns in {approx} 12 m. Radial confinement of the beam is achieved with 2.5 T pulsed solenoids. In the initial hardware configuration, 50 nC of Li{sup +} will be accelerated to 1.25 MeV and allowed to drift-compress to a peak current of {approx}40 A. The project started in the summer of 2009. Construction of the accelerator will be completed in the fall of 2011 and will provide a worldwide unique opportunity for ion-driven warm dense matter experiments as well as research related to novel beam manipulations for heavy ion fusion drivers.

  1. Lattice Boltzmann model for collisionless electrostatic drift wave turbulence obeying Charney-Hasegawa-Mima dynamics

    NASA Astrophysics Data System (ADS)

    Held, M.; Kendl, A.

    2015-10-01

    A lattice Boltzmann method (LBM) approach to the Charney-Hasegawa-Mima (CHM) model for adiabatic drift wave turbulence in magnetised plasmas is implemented. The CHM-LBM model contains a barotropic equation of state for the potential, a force term including a cross-product analogous to the Coriolis force in quasigeostrophic models, and a density gradient source term. Expansion of the resulting lattice Boltzmann model equations leads to cold-ion fluid continuity and momentum equations, which resemble CHM dynamics under drift ordering. The resulting numerical solutions of standard test cases (monopole propagation, stable drift modes and decaying turbulence) are compared to results obtained by a conventional finite difference scheme that directly discretizes the CHM equation. The LB scheme resembles characteristic CHM dynamics apart from an additional shear in the density gradient direction. The occurring shear reduces with the drift ratio and is ascribed to the compressible limit of the underlying LBM.

  2. HIV testing in community pharmacies and retail clinics: A model to expand access to screening for HIV infection

    PubMed Central

    Weidle, Paul J.; Lecher, Shirley; Botts, Linda W.; Jones, LaDawna; Spach, David H.; Alvarez, Jorge; Jones, Rhondette; Thomas, Vasavi

    2015-01-01

    Objective To test the feasibility of offering rapid, point-of-care human immunodeficiency virus (HIV) testing at community pharmacies and retail clinics. Design Pilot program to determine how to implement confidential HIV testing services in community pharmacies and retail clinics. Setting 21 community pharmacies and retail clinics serving urban and rural patients in the United States, from August 2011 to July 2013. Participants 106 community pharmacy and retail clinic staff members. Intervention A model was developed to implement confidential HIV counseling and testing services using community pharmacy and retail clinic staff as certified testing providers, or through collaborations with organizations that provide HIV testing. Training materials were developed and sites selected that serve patients from urban and rural areas to pilot test the model. Each site established a relationship with its local health department for HIV testing policies, developed referral lists for confirmatory HIV testing/care, secured a CLIA Certificate of Waiver, and advertised the service. Staff were trained to perform a rapid point-of-care HIV test on oral fluid, and provide patients with confidential test results and information on HIV. Patients with a preliminary positive result were referred to a physician or health department for confirmatory testing and, if needed, HIV clinical care. Main outcome measures Number of HIV tests completed and amount of time required to conduct testing. Results The 21 participating sites administered 1,540 HIV tests, with 1,087 conducted onsite by staff during regular working hours and 453 conducted at 37 different HIV testing events (e.g., local health fairs). The median amount of time required for pretest counseling/consent, waiting for test results, and posttest counseling was 4, 23, and 3 minutes, respectively. A majority of the sites (17) said they planned to continue HIV testing after the project period ended and would seek assistance or support

  3. Health insurance for the poor decreases access to HIV testing in antenatal care: evidence of an unintended effect of health insurance reform in Colombia

    PubMed Central

    Ettenger, Allison; Bärnighausen, Till; Castro, Arachu

    2014-01-01

    Prevention of mother-to-child transmission of HIV was added to standard antenatal care (ANC) in 2000 for Colombians enrolled in the two national health insurance schemes, the ‘subsidized regime’ (covering poor citizens) and the ‘contributory regime’ (covering salaried citizens with incomes above the poverty threshold), which jointly covered 80% of the total Colombian population as of 2007. This article examines integration of HIV testing in ANC through the relationship between ordering an HIV test with the type of health insurance, including lack of health insurance, using data from the nationally representative 2005 Colombia Demographic and Health Survey. Overall, health-care providers ordered an HIV test for only 35% of the women attending ANC. We regressed the order of an HIV test during ANC on health systems characteristics (type of insurance and type of ANC provider), women’s characteristics (age, wealth, educational attainment, month of pregnancy at first antenatal visit, HIV knowledge, urban vs. rural residence and sub-region of residence) and children’s characteristics (birth order and birth year). Women enrolled in the subsidized regime were significantly less likely to be offered and receive an HIV test in ANC than women without any health insurance (adjusted odds ratio = 0.820, P < 0.001), when controlling for the other independent variables. Wealth, urban residence, birth year of the child and the type of health-care provider seen during the ANC visit were significantly associated with providers ordering an HIV test for a woman (all P < 0.05). Our findings suggest that enrolment in the subsidized regime reduced access to HIV testing in ANC. Additional research is needed to elucidate the mechanisms through which the potential effect of health insurance coverage on HIV testing in ANC occurs and to examine whether enrolment in the subsidized regime has affected access to other essential health services. PMID:23598426

  4. Drift emplaced waste package thermal response

    SciTech Connect

    Ruffner, D.J.; Johnson, G.L.; Platt, E.A.; Blink, J.A.; Doering, T.W.

    1993-12-31

    Thermal calculations of the effects of radioactive waste decay heat on the potential repository at Yucca Mountain, Nevada, have been conducted by the Yucca Mountain Site Characterization Project (YMP) at Lawrence Livermore National Lab. (LLNL) in conjunction with the B&W Fuel Co. For a number of waste package spacings, these 3D transient calculations use the TOPAZ3D code to predict drift wall temperatures to 10,000 years following emplacement. Systematic temperature variation occurs as a function of fuel age at emplacement and Areal Mass Loading (AML) during the first few centuries after emplacement. After about 1000 years, emplacement age is not a strong driver on rock temperature; AML has a larger impact. High AMLs occur when large waste packages are emplaced end-to-end in drifts. Drift emplacement of equivalent packages results in lower rock temperatures than borehole emplacement. For an emplacement scheme with 50% of the drift length occupied by packages, an AML of 138 MTU/acre is about three times higher than the Site Characterization Plan-Conceptual Design (SCP-CD) value. With this higher AML (requiring only 1/3 of the SCP-CD repository footprint), peak drift wall temperatures do not exceed 160{degrees}C, but rock temperatures exceed the boiling point of water for about 3000 years. These TOPAZ3D results have been compared with reasonable agreement with two other computer codes.

  5. Drift emplaced waste package thermal response

    SciTech Connect

    Ruffner, D.J.; Johnson, G.L.; Platt, E.A.; Blink, J.A.; Doering, T.W.

    1993-01-01

    Thermal calculations of the effects of radioactive waste decay heat on the I repository at Yucca Mountain, Nevada have been conducted by the Yucca Mountain Site Characterization Project (YMP) at Lawrence Livermore National Laboratory (LLNL) in conjunction with the B&W Fuel Company. For a number of waste package spacings, these 3D transient calculations use the TOPAZ3D code to predict drift wall temperatures to 10,000 years following emplacement. Systematic tcniperature variation occurs as a function of fuel age at emplacement and Areal Mass Loading (AML) during the first few centuries after emplacement. After about 1000 years, emplacement age is not a strong driver on rock temperature; AML has a larger impact. High AMLs occur when large waste packages are emplaced end-tocnd in drifts. Drift emplacement of equivalent packages results in lower rock teniperatures than borehole emplacement. For an emplacement scheme with 50% of the drift length occupied by packages, an AML of 138 MTU/acre is about three times higher than the Site Characterization Plan-Conceptual Design (SCP-CD) value. With this higher AML (requiring only 1/3 of the SCP-CD repository footprint), peak drift wall temperatures do not exceed 160*C, but rock temperatures excetd the boiling point of water for about 3000 years. These TOPAZ3D results Iiive been compared with reasonable agreement with two other computer codes.

  6. Understanding regional and local scale hydraulic processes controlling recharge through drift

    NASA Astrophysics Data System (ADS)

    Cuthbert, M. O.; Mackay, R.; Lawrence, A. R.; Peach, D.

    2003-04-01

    The estimation of groundwater recharge is a fundamental component of any water resources appraisal or aquifer vulnerability study. Although methods for evaluating the distribution of potential recharge leaving the soil zone are relatively well developed, the recharge signal to the underlying aquifer can be significantly modified in the presence of superficial drift deposits. Current mapping of the drift does not often provide representations of drift distribution and structure suitable for understanding the hydraulics of the subsurface flow system. The current research seeks to develop new understanding of the processes contributing to recharge in heterogeneous drift sequences, their characterisation in models and their parameterisation through field experiments. Surface and downhole geophysical sampling through regional to micro scales will be integrated with textural measurements and hydraulic monitoring to characterise drift deposits in parts of the Tern catchment (Shropshire, UK) and gain insight into the relationship between flow behaviour and geological structure. Fieldwork will then culminate in a series of flow and tracer tests at a well characterised site with continuous monitoring including the use of recently developed 4-D resistivity imaging methods to monitor the movement of natural and applied waters through the drift. Conceptual and numerical models will be used throughout the project to test ideas and drive the experimental designs. The study aims to assess the relative importance of hydraulic processes at a range of scales and, by back analysis, the degree of sophistication required in fieldwork to construct a useful model of flow patterns within the drift. The potential usefulness of various surface and downhole geophysical techniques within drift and unsaturated zone studies will be critically assessed.

  7. Health care providers and direct-to-consumer access and advertising of genetic testing in the United States

    PubMed Central

    2011-01-01

    Marketing pressures, regulatory policies, clinical guidelines, and consumer demand all affect health care providers' knowledge and use of health-related genetic tests that are sold and/or advertised to consumers. In addition, clinical guidelines, regulatory policies, and educational efforts are needed to promote the informed use of genetic tests that are sold and advertised to consumers and health care providers. A shift in culture regarding the regulation of genetic tests that are sold directly to consumers is suggested: by recent actions taken by the US Food and Drug Administration (FDA), including letters sent to direct-to-consumer (DTC) genetic testing companies stating that their tests meet the definition of medical devices; by public meetings held by the FDA to discuss laboratory developed tests; and by the convening of the Molecular and Clinical Genetics Panel to gather input on scientific issues concerning DTC genetic tests that make medical claims. This review provides a brief overview of DTC advertising and the regulation of pharmaceuticals and genetic tests in the United States. It highlights recent changes in the regulatory culture regarding genetic tests that are sold to consumers, and discusses the impact on health care providers of selling and advertising genetic tests directly to consumers. PMID:22204616

  8. Health care providers and direct-to-consumer access and advertising of genetic testing in the United States.

    PubMed

    Myers, Melanie F

    2011-01-01

    Marketing pressures, regulatory policies, clinical guidelines, and consumer demand all affect health care providers' knowledge and use of health-related genetic tests that are sold and/or advertised to consumers. In addition, clinical guidelines, regulatory policies, and educational efforts are needed to promote the informed use of genetic tests that are sold and advertised to consumers and health care providers. A shift in culture regarding the regulation of genetic tests that are sold directly to consumers is suggested: by recent actions taken by the US Food and Drug Administration (FDA), including letters sent to direct-to-consumer (DTC) genetic testing companies stating that their tests meet the definition of medical devices; by public meetings held by the FDA to discuss laboratory developed tests; and by the convening of the Molecular and Clinical Genetics Panel to gather input on scientific issues concerning DTC genetic tests that make medical claims. This review provides a brief overview of DTC advertising and the regulation of pharmaceuticals and genetic tests in the United States. It highlights recent changes in the regulatory culture regarding genetic tests that are sold to consumers, and discusses the impact on health care providers of selling and advertising genetic tests directly to consumers. PMID:22204616

  9. Limits of Neutral Drift: Lessons from the In Vitro Evolution of Two Ribozymes

    PubMed Central

    Petrie, Katherine L.; Joyce, Gerald F.

    2014-01-01

    The relative contributions of adaptive selection and neutral drift to observed genetic change are unknown, but likely depend on the inherent abundance of functional genotypes in sequence space and how accessible those genotypes are to one another. To better understand the relative roles of selection and drift in evolution, local fitness landscapes for two different RNA ligase ribozymes were examinedusing a continuous in vitro evolution system under conditions that foster the capacity for neutral drift to mediate genetic change.The exploration of sequence spacewas acceleratedby increasing the mutation rate using mutagenic nucleotide analogs. Drift wasencouraged by carrying out evolution within millions of separate compartments to exploit the founder effect. Deep sequencing of individuals from the evolved populations revealed that the distribution of genotypes did not escape the starting local fitness peak, remaining clustered around the sequenceused to initiate evolution.This is consistent with a fitness landscape where high-fitness genotypes are sparse and well isolated, and suggests, at least in this context, that neutral drift alone is not a primary driver of genetic change. Neutral driftdoes, however, provide a repository of genetic variation upon which adaptive selection can act. PMID:25155818

  10. Comparison of Vertical Drifts of ISR and Magnetometer Data Measurements at the Magnetic Equator

    NASA Astrophysics Data System (ADS)

    Condor P, P. J.

    2014-12-01

    We compare vertical drifts measured with the Jicamarca incoherent scatter radar (ISR) and drifts estimated from magnetometer data applying a Neural Network data processing technique. For the application of the Neural Network (NN) method, we use the magnitude of the horizontal (H) component of the magnetic field measured with magnetometers at Jicamarca and Piura (Peru). The data was collected between the years 2002 and 2013. In training the NN we use the difference between the magnitudes of the horizontal components (dH) measured at JRO (placed at the magnetic equator) and Piura (displaced 5° away). Additional parameters used are F10.7 and Ap indexes. The estimates obtained with the NN procedure are very good. We have an RMS error of 3.7 m/s using dH as an input of the NN while the error is 3.9 m/s when we use the component H of JRO as an input. The results are validated using the set of vertical drifts observations collected with the Jicamarca incoherent scatter radar. The estimated drifts can be accessed using the following website: http://jro.igp.gob.pe/driftnn. In the poster, we show the comparison of vertical drifts from 2002 to 2013 where we discuss the agreement between magnetometer and ISR data.

  11. EMPLACEMENT DRIFT INVERT-LOW STEEL EVALUATION

    SciTech Connect

    M. E. Taylor and D. H. Tang

    2000-09-29

    This technical report evaluates and develops options for reducing the amount of steel in the emplacement drift invert. Concepts developed in the ''Invert Configuration and Drip Shield Interface'' were evaluated to determine material properties required for the proposed invert concepts. Project requirements documents prescribe the use of a carbon steel frame for the invert with a granular material of crushed tuff as ballast. The ''Invert Configuration and Drip Shield Interface'' developed three concepts: (1) All-Ballast Invert; (2) Modified Steel Invert with Ballast; and (3) Steel Tie with Ballast Invert. Analysis of the steel frame members, runway beams, and guide beams, for the modified steel invert with ballast, decreased the quantity of steel in the emplacement drift invert, however a substantial steel support frame for the gantry and waste package/pallet assembly is still required. Use of one of the other two concepts appears to be an alternative to the steel frame and each of the concepts uses considerably less steel materials. Analysis of the steel tie with ballast invert shows that the bearing pressure on the ballast under the single steel tie, C 9 x 20, loaded with the waste package/pallet assembly, drip shield, and backfill exceeds the upper bound of the allowable bearing capacity for tuff used in this study. The single tie, C 10 x 20, will also fail for the same loading condition except for the tie length of 4.2 meters and longer. Analysis also shows that with two ties, C 9 or 10 x 20's, the average ballast pressure is less than the allowable bearing capacity. Distributing the waste package/pallet, drip shield, and backfill loads to two steel ties reduces the contact bearing pressure. Modifying the emplacement pallet end beams to a greater width, reducing the tie spacing, and increasing the width of the ties would ensure that the pallet beams are always supported by two steel ties. Further analysis is required to determine compatible tie size and spacing

  12. Environmental assessment for the Area 5 radioactive waste management site access improvement at the Nevada Test Site

    SciTech Connect

    1997-11-01

    The United States Department of Energy has prepared an Environmental Assessment which analyzes the potential environmental effects of improving access to its AREA 5 RWMS at the NTS. The EA evaluates the potential impacts of constructing an extension of the Cane Springs Road between Mercury Highway and the 5-01 Road. Three alternative actions are also evaluated: (1) construction of a new road along the existing alignment of the Powerline Road between Mercury Highway and the 5-01 Road, (2) upgrading the existing 5-01 Road, and (3) taking no action. The purpose and need for improving access to the RWMS are addressed in Section 1.0 of the EA. A detailed description of the proposed action and alternatives is in Section 2.0. Section 3.0 describes the affected environment and Section 4.0 the environmental effects of the proposed action and alternatives. Health and transportation effects, accident scenarios, cumulative effects, and other relevant information are found in Sections 5.0 through 12.0 of the EA. DOE determined that the alternative action of upgrading the existing 5-01 Road would best meet the needs of the agency.

  13. Pharmacy staff characteristics associated with support for pharmacy-based HIV-testing in pharmacies participating in the New York State Expanded Access Syringe Exchange Program

    PubMed Central

    Amesty, Silvia; Blaney, Shannon; Crawford, Natalie D.; Rivera, Alexis V.; Fuller, Crystal

    2013-01-01

    Objective To determine support of in-pharmacy HIV-testing among pharmacy staff and the individual-level characteristics associated with in-pharmacy HIV testing support. Design Descriptive, nonexperimental, cross-sectional study. Setting New York City (NYC) during January 2008 to March 2009. Intervention 131 pharmacies registered in the Expanded Syringe Access Program (ESAP) completed a survey. Participants 480 pharmacy staff, including pharmacists, owners/managers, and technicians/clerks. Main outcome measures Support of in-pharmacy HIV testing. Results Support of in-pharmacy HIV testing is high among pharmacy staff (79.4%). Pharmacy staff that supported in-pharmacy vaccinations were significantly more likely to support in-pharmacy HIV testing. Pharmacy staff that think that selling syringes to IDUs causes the community to be littered with dirty syringes were significantly less likely to support in-pharmacy HIV testing. Conclusion Support for in-pharmacy HIV testing is high among our sample of ESAP pharmacy staff actively involved in non-prescription syringe sales. These findings suggest that active ESAP pharmacy staff may be amenable to providing HIV counseling and testing to injection drug users and warrants further investigation. PMID:22825227

  14. Count-Rate Statistics for Drift Detectors

    PubMed Central

    Pietraski, Philip J.; Furenlid, Lars R.

    2015-01-01

    Synchrotron light sources are low-duty-cycle pulsed X-ray sources, a fact that is often neglected in estimating the count-rate capabilities of photon-counting detectors in synchrotron-based experiments. In this paper, we demonstrate the effect that this has on the pileup statistics of drift detectors. We derive expressions for the cases of continuous and pulsed X-ray sources. We consider a pulsed source with period that is either much less than the shaper support time or much less than the average drift time. We also consider a pulsed source with a period that is long or comparable to both the shaper support and the drift time. These conditions correspond to normal and reduced bunch fill patterns of synchrotrons. PMID:27103751

  15. Drift Mode Calculations in Nonaxisymmetric Geometry

    SciTech Connect

    G. Rewoldt; L.-P. Ku; W.A. Cooper; W.M. Tang

    1999-07-01

    A fully kinetic assessment of the stability properties of toroidal drift modes has been obtained for nonaxisymmetric (stellarator) geometry, in the electrostatic limit. This calculation is a comprehensive solution of the linearized gyrokinetic equation, using the lowest-order ''ballooning representation'' for high toroidal mode number instabilities, with a model collision operator. Results for toroidal drift waves destabilized by temperature gradients and/or trapped particle dynamics are presented, using three-dimensional magnetohydrodynamic equilibria generated as part of a design effort for a quasiaxisymmetric stellarator. Comparisons of these results with those obtained for typical tokamak cases indicate that the basic trends are similar.

  16. Generalized Drift-Diffusion Model In Semiconductors

    SciTech Connect

    Mesbah, S.; Bendib-Kalache, K.; Bendib, A.

    2008-09-23

    A new drift-diffusion model is proposed based on the computation of the stationary nonlocal current density. The semi classical Boltzmann equation is solved keeping all the anisotropies of the distribution function with the use of the continued fractions. The conductivity is calculated in the linear approximation and for arbitrary collision frequency with respect to Kv{sub t} where K{sup -1} is the characteristic length scale of the system and V{sub t} is the thermal velocity. The nonlocal conductivity can be used to close the generalized drift-diffusion equations valid for arbitrary collisionality.

  17. Drift estimation from a simple field theory

    SciTech Connect

    Mendes, F. M.; Figueiredo, A.

    2008-11-06

    Given the outcome of a Wiener process, what can be said about the drift and diffusion coefficients? If the process is stationary, these coefficients are related to the mean and variance of the position displacements distribution. However, if either drift or diffusion are time-dependent, very little can be said unless some assumption about that dependency is made. In Bayesian statistics, this should be translated into some specific prior probability. We use Bayes rule to estimate these coefficients from a single trajectory. This defines a simple, and analytically tractable, field theory.

  18. Quantum Computation with Phase Drift Errors

    NASA Astrophysics Data System (ADS)

    Miquel, César; Paz, Juan Pablo; Zurek, Wojciech Hubert

    1997-05-01

    We numerically simulate the evolution of an ion trap quantum computer made out of 18 ions subject to a sequence of nearly 15 000 laser pulses in order to find the prime factors of N = 15. We analyze the effect of random and systematic phase drift errors arising from inaccuracies in the laser pulses which induce over (under) rotation of the quantum state. Simple analytic estimates of the tolerance for the quality of driving pulses are presented. We examine the use of watchdog stabilization to partially correct phase drift errors concluding that, in the regime investigated, it is rather inefficient.

  19. Shock drift mechanism for Forbush decreases

    NASA Technical Reports Server (NTRS)

    Cheng, Andrew F.; Sarris, E. T.; Dodopoulos, C.

    1990-01-01

    Consideration is given to the way in which Forbush decreases can arise from variable drifts in nonuniform shocks, where the variation in shock strength along the shock front causes both the shock drift distance and the energy gain to become variable. More particles can then be transported out of a given region of space and energy interval than were transported in, so a spacecraft passing through this region can observe a Forbush decrease in this energy interval despite shock energization and compression. A simple example of how this can occur is presented.

  20. Shock drift mechanism for Forbush decreases

    SciTech Connect

    Cheng, A.F.; Sarris, E.T.; Dodopoulos, C. Thrace Democritus Univ., Xanthe )

    1990-02-01

    Consideration is given to the way in which Forbush decreases can arise from variable drifts in nonuniform shocks, where the variation in shock strength along the shock front causes both the shock drift distance and the energy gain to become variable. More particles can then be transported out of a given region of space and energy interval than were transported in, so a spacecraft passing through this region can observe a Forbush decrease in this energy interval despite shock energization and compression. A simple example of how this can occur is presented. 20 refs.

  1. Drifts of Dust or Something Else?

    NASA Technical Reports Server (NTRS)

    2004-01-01

    While the interior and far walls of the crater dubbed 'Bonneville' can be seen in the background, the dominant foreground features in this 180-degree navigation camera mosaic are the wind-deposited drifts of dust or sand. NASA's Mars Exploration Rover Spirit completed this mosaic on sol 71, March 15, 2004, from its newest location at the rim of 'Bonneville' crater.

    Scientists are interested in these formations in part because they might give insight into the processes that formed some of the material within the crater. Thermal emission measurements by the rover indicate that the dark material just below the far rim of this crater is spectrally similar to rocks that scientists have analyzed along their journey to this location. They want to know why this soil-like material has a spectrum that more closely resembles rocks rather than other soils examined so far. The drifts seen in the foreground of this mosaic might have the answer. Scientists hypothesize that these drifts might consist of wind-deposited particles that are the same as the dark material found against the back wall of the crater. If so, Spirit may spend time studying the material and help scientists understand why it is different from other fine-grained material seen at Gusev.

    The drifts appear to be lighter in color than the dark material deposited on the back wall of the crater. They might be covered by a thin deposit of martian dust, or perhaps the drift is like other drifts seen during Spirit's journey and is just a collection of martian dust.

    To find out, Spirit will spend some of sol 72 digging its wheels into the drift to uncover its interior. After backing up a bit, Spirit will use the panoramic camera and miniature thermal emission spectrometer to analyze the scuffed area. If the interior material has a similar spectrum to the dark deposit in the crater, then Spirit will most likely stay here a little longer to study the drift with the instruments on its robotic arm. If the

  2. Voluntary Counseling and Testing Services: Breaking Resistance to Access and Utilization among the Youths in Rakai District of Uganda

    ERIC Educational Resources Information Center

    Sebudde, Stephen; Nangendo, Florence

    2009-01-01

    Voluntary counseling and testing is important in controlling the spread of HIV, especially among adolescents. The aim is to describe the perceptions of adolescents of the best options to providing voluntary counseling and testing services to them in Rakai District Uganda. A cross-sectional descriptive study was carried out among male and female…

  3. Use of a terrestrial LIDAR sensor for drift detection in vineyard spraying.

    PubMed

    Gil, Emilio; Llorens, Jordi; Llop, Jordi; Fàbregas, Xavier; Gallart, Montserrat

    2013-01-01

    The use of a scanning Light Detection and Ranging (LIDAR) system to characterize drift during pesticide application is described. The LIDAR system is compared with an ad hoc test bench used to quantify the amount of spray liquid moving beyond the canopy. Two sprayers were used during the field test; a conventional mist blower at two air flow rates (27,507 and 34,959 m3·h(-1)) equipped with two different nozzle types (conventional and air injection) and a multi row sprayer with individually oriented air outlets. A simple model based on a linear function was used to predict spray deposit using LIDAR measurements and to compare with the deposits measured over the test bench. Results showed differences in the effectiveness of the LIDAR sensor depending on the sprayed droplet size (nozzle type) and air intensity. For conventional mist blower and low air flow rate; the sensor detects a greater number of drift drops obtaining a better correlation (r = 0.91; p < 0.01) than for the case of coarse droplets or high air flow rate. In the case of the multi row sprayer; drift deposition in the test bench was very poor. In general; the use of the LIDAR sensor presents an interesting and easy technique to establish the potential drift of a specific spray situation as an adequate alternative for the evaluation of drift potential. PMID:23282583

  4. Use of a Terrestrial LIDAR Sensor for Drift Detection in Vineyard Spraying

    PubMed Central

    Gil, Emilio; Llorens, Jordi; Llop, Jordi; Fàbregas, Xavier; Gallart, Montserrat

    2013-01-01

    The use of a scanning Light Detection and Ranging (LIDAR) system to characterize drift during pesticide application is described. The LIDAR system is compared with an ad hoc test bench used to quantify the amount of spray liquid moving beyond the canopy. Two sprayers were used during the field test; a conventional mist blower at two air flow rates (27,507 and 34,959 m3·h−1) equipped with two different nozzle types (conventional and air injection) and a multi row sprayer with individually oriented air outlets. A simple model based on a linear function was used to predict spray deposit using LIDAR measurements and to compare with the deposits measured over the test bench. Results showed differences in the effectiveness of the LIDAR sensor depending on the sprayed droplet size (nozzle type) and air intensity. For conventional mist blower and low air flow rate; the sensor detects a greater number of drift drops obtaining a better correlation (r = 0.91; p < 0.01) than for the case of coarse droplets or high air flow rate. In the case of the multi row sprayer; drift deposition in the test bench was very poor. In general; the use of the LIDAR sensor presents an interesting and easy technique to establish the potential drift of a specific spray situation as an adequate alternative for the evaluation of drift potential. PMID:23282583

  5. The NIH genetic testing registry: a new, centralized database of genetic tests to enable access to comprehensive information and improve transparency

    PubMed Central

    Rubinstein, Wendy S.; Maglott, Donna R.; Lee, Jennifer M.; Kattman, Brandi L.; Malheiro, Adriana J.; Ovetsky, Michael; Hem, Vichet; Gorelenkov, Viatcheslav; Song, Guangfeng; Wallin, Craig; Husain, Nora; Chitipiralla, Shanmuga; Katz, Kenneth S.; Hoffman, Douglas; Jang, Wonhee; Johnson, Mark; Karmanov, Fedor; Ukrainchik, Alexander; Denisenko, Mikhail; Fomous, Cathy; Hudson, Kathy; Ostell, James M.

    2013-01-01

    The National Institutes of Health Genetic Testing Registry (GTR; available online at http://www.ncbi.nlm.nih.gov/gtr/) maintains comprehensive information about testing offered worldwide for disorders with a genetic basis. Information is voluntarily submitted by test providers. The database provides details of each test (e.g. its purpose, target populations, methods, what it measures, analytical validity, clinical validity, clinical utility, ordering information) and laboratory (e.g. location, contact information, certifications and licenses). Each test is assigned a stable identifier of the format GTR000000000, which is versioned when the submitter updates information. Data submitted by test providers are integrated with basic information maintained in National Center for Biotechnology Information’s databases and presented on the web and through FTP (ftp.ncbi.nih.gov/pub/GTR/_README.html). PMID:23193275

  6. Accessing HIV testing and treatment among men who have sex with men in China: a qualitative study.

    PubMed

    Wei, Chongyi; Yan, Hongjing; Yang, Chuankun; Raymond, H Fisher; Li, Jianjun; Yang, Haitao; Zhao, Jinkou; Huan, Xiping; Stall, Ron

    2014-01-01

    Barriers to HIV testing and HIV care and treatment pose significant challenges to HIV prevention among men who have sex with men (MSM) in China. We carried out a qualitative study to identify barriers and facilitators to HIV testing and treatment among Chinese MSM. In 2012, seven focus group (FG) discussions were conducted with 49 MSM participants in Nanjing, China. Purposive sampling was used to recruit a diverse group of MSM participants. Semi-structured interviews were conducted to collect FG data. Major barriers to testing included gay- and HIV-related stigma and discrimination, relationship type and partner characteristics, low perception of risk or threat, HIV is incurable or equals death, concerns of confidentiality, unaware that testing is offered for free, and name-based testing. Key facilitators of testing included engaging in high-risk sex, sense of responsibility for partner, collectivism, testing as a part of standard/routine medical care, MSM-friendly medical personnel, increased acceptance of gay/bisexual men by the general public, legal recognition and protection of homosexuals, and home self-testing. Barriers to treatment included negative coping, nondisclosure to families, misconceptions of domestically produced antiretroviral drugs (ARVs) and the benefits of treatment, and costs associated with long-term treatment. Facilitators of treatment included sense of hopefulness that a cure would be found, the cultural value of longevity, peer social support and professional psychological counseling, affordable and specialized treatment and care, and reduced HIV-related stigma and discrimination. Finally, for both testing and treatment, more educational and promotional activities within MSM communities and among the general public are needed. PMID:23909807

  7. Preliminary geochemical and physical testing of materials for plugging of man-made accesses to a repository in basalt

    SciTech Connect

    Taylor, C.L.; Anttonen, G.J.; O'Rourke, J.E.; Allirot, D.

    1980-04-01

    The available data on environmental conditions (both natural and man-made) at the Hanford Site are sufficient for preconceptual plug system design. Results of the geochemical testing program indicate that preferred candidate plug materials are chemically nonreactive during laboratory tests that simulated some of the expected environmental conditions. Agitated, crushed-basalt samples and mixtures containing basalt were found to be self-cementing under the hydrothermal conditions. Materials considered most suitable for consideration in future test programs and preconceptual plug design are mixtures of natural materials (basalt, clay, glaciofluvial sand, gravel, and zeolite) and processed natural materials (portland cement Type V and grouts plus additives).

  8. Test-Bed Design and Implementation of High-Definition Multimedia Interface Based 3D Broadcast Coarse Wavelength-Division Multiplexing Access Network

    NASA Astrophysics Data System (ADS)

    Mizusawa, Jun-Ichi

    2011-10-01

    Test-bed operations of three real-time transmission types are described: a three-dimensional (+two-dimensional) high-definition multimedia interface broadcast on point-to-multi-point connections, a two-dimensional high-definition multimedia interface broadcast on multi-point-to-multi-point connections, and a three-dimensional high-definition multimedia interface full duplex on a point-to-point connection. The network design has an optical broadcast topology centered with an "optical hub." This article first introduces the design and implementation, then explains the issues and further considerations for implementing a high-definition multimedia interface based three-dimensional broadcast access network.

  9. Detecting and correcting sensor drifts in long-term weather data.

    PubMed

    von Arx, Georg; Dobbertin, Matthias; Rebetez, Martine

    2013-06-01

    Quality control of long-term monitoring data of thousands and millions of individual records as present in meteorological data is cumbersome. In such data series, sensor drifts, stalled values, and scale shifts may occur and potentially result in flawed conclusions if not noticed and handled properly. However, there is no established standard procedure to perform quality control of high-frequency meteorological data. In this paper, we outline a procedure to remove sensor drift in high-frequency data series using the example of 15-year-long sets of hourly relative humidity (RH) data from 28 stations subdivided into 202 individual sensor operation periods. The procedure involves basic quality control, relative homogeneity testing, and drift removal. Significant sensor drifts were observed in 40.6 % of all sensor operation periods. The drifts varied between data series and depended in a complex, usually inconsistent way on absolute RH values; within single series for instance, a drift could be negative in the lower RH range and positive in the upper RH range. Detrending changed RH values by, on average, 1.96 %. For one fifth of the detrended data, adjustments were 2.75 % and more of the measured value, and in one tenth 4.75 % and more. Overall, drifts were strongest for RH values close to 100 %. The detrending procedure proved to effectively remove sensor drifts. The principles of the procedure also apply to other meteorological parameters and more generally to any time series of data for which comparable reference data are available. PMID:22915222

  10. Detecting genetic drift versus selection in human evolution

    PubMed Central

    Ackermann, Rebecca Rogers; Cheverud, James M.

    2004-01-01

    Recent paleoanthropological discoveries reveal a diverse, potentially speciose human fossil record. Such extensive morphological diversity results from the action of divergent evolutionary forces on an evolving lineage. Here, we apply quantitative evolutionary theory to test whether random evolutionary processes alone can explain the morphological diversity seen among fossil australopith and early Homo crania from the Plio–Pleistocene. We show that although selection may have played an important role in diversifying hominin facial morphology in the late Pliocene, this is not the case during the early evolution of the genus Homo, where genetic drift was probably the primary force responsible for facial diversification. PMID:15604148

  11. Analysis and encoder prevention techniques for pathological IDCT drift accumulation in static video scenes

    NASA Astrophysics Data System (ADS)

    Sullivan, Gary J.

    2007-09-01

    This paper discusses the problem of severe pathological encoder-decoder IDCT drift in video compression coding when using a very small quantization step size and typical encoding techniques to encode video sequences with areas of completely static source content. We suggest that there are two ways to try to address the problem: 1) using a highaccuracy IDCT (or an encoder-matched IDCT) in a decoder design, and 2) using encoder techniques to avoid such drift build-up. The primary problem is asserted to be the encoder's behavior. Effective encoder techniques to avoid the problem are described, including a simple "generalized Morris drift test", which is suggested as being superior to the test currently described in the MPEG-2 video specification. Experiment results are reported to show that performing this test in an encoder will completely solve the problem. Other encoding techniques to address the problem are also discussed.

  12. Qualitative Assessment of Barriers and Facilitators of Access to HIV Testing Among Men Who Have Sex with Men in China.

    PubMed

    Liu, Yu; Sun, Xiaoyun; Qian, Han-Zhu; Yin, Lu; Yan, Zheng; Wang, Lijuan; Jiang, Shulin; Lu, Hongyan; Ruan, Yuhua; Shao, Yiming; Vermund, Sten H; Amico, K Rivet

    2015-09-01

    Diagnosis of HIV is the entry point into the continuum of HIV care; a well-recognized necessary condition for the ultimate prevention of onward transmission. In China, HIV testing rates among men who have sex with men (MSM) are low compared to other high risk subgroups, yet experiences with HIV testing among MSM in China are not well understood. To address this gap and prepare for intervention development to promote HIV testing and rapid linkage to treatment, six focus groups (FGs) were conducted with MSM in Beijing (40 HIV-positive MSM participated in one of four FGs and 20 HIV-negative or status unknown MSM participated in one of two FGs). Major themes reported as challenges to HIV testing included stigma and discrimination related to HIV and homosexuality, limited HIV knowledge, inconvenient clinic times, not knowing where to get a free test, fear of positive diagnosis or nosocomial infection, perceived low service quality, and concerns/doubts about HIV services. Key facilitators included compensation, peer support, professionalism, comfortable testing locations, rapid testing, referral and support after diagnosis, heightened sense of risk through engagement in high-risk behaviors, sense of responsibility to protect self, family and partner support, and publicity via social media. Themes and recommendations were generally consistent across HIV-positive and negative/status unknown groups, although examples of enacted stigma were more prevalent in the HIV-positive groups. Findings from our study provide policy suggestions for how to bolster current HIV prevention intervention efforts to enhance 'test-and-treat' strategies for Chinese MSM. PMID:26186029

  13. Qualitative Assessment of Barriers and Facilitators of Access to HIV Testing Among Men Who Have Sex with Men in China

    PubMed Central

    Liu, Yu; Sun, Xiaoyun; Yin, Lu; Yan, Zheng; Wang, Lijuan; Jiang, Shulin; Lu, Hongyan; Ruan, Yuhua; Shao, Yiming; Vermund, Sten H.

    2015-01-01

    Abstract Diagnosis of HIV is the entry point into the continuum of HIV care; a well-recognized necessary condition for the ultimate prevention of onward transmission. In China, HIV testing rates among men who have sex with men (MSM) are low compared to other high risk subgroups, yet experiences with HIV testing among MSM in China are not well understood. To address this gap and prepare for intervention development to promote HIV testing and rapid linkage to treatment, six focus groups (FGs) were conducted with MSM in Beijing (40 HIV-positive MSM participated in one of four FGs and 20 HIV-negative or status unknown MSM participated in one of two FGs). Major themes reported as challenges to HIV testing included stigma and discrimination related to HIV and homosexuality, limited HIV knowledge, inconvenient clinic times, not knowing where to get a free test, fear of positive diagnosis or nosocomial infection, perceived low service quality, and concerns/doubts about HIV services. Key facilitators included compensation, peer support, professionalism, comfortable testing locations, rapid testing, referral and support after diagnosis, heightened sense of risk through engagement in high-risk behaviors, sense of responsibility to protect self, family and partner support, and publicity via social media. Themes and recommendations were generally consistent across HIV-positive and negative/status unknown groups, although examples of enacted stigma were more prevalent in the HIV-positive groups. Findings from our study provide policy suggestions for how to bolster current HIV prevention intervention efforts to enhance ‘test-and-treat’ strategies for Chinese MSM. PMID:26186029

  14. Evaluation of spray drift using low speed wind tunnel measurements and dispersion modeling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this work was to evaluate the EPA’s proposed Test Plan for the validation testing of pesticide spray drift reduction technologies (DRTs) for row and field crops, focusing on the evaluation of ground application systems using the low-speed wind tunnel protocols and processing the dat...

  15. Effects of drift from 39 aerially-applied herbicides on production pond plankton and water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty-nine, aerially-applied row crop herbicides were tested for possible adverse effects from drift on fish pond plankton and water quality over 10 years of testing at the University of Arkansas at Pine Bluff. Phytoplankton biomass and productivity, 6 water quality parameters of interest in aquac...

  16. 40 CFR 1065.550 - Gas analyzer range verification and drift verification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Gas analyzer range verification and drift verification. 1065.550 Section 1065.550 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Performing an Emission Test Over Specified Duty Cycles § 1065.550 Gas analyzer...

  17. Aging effect in the BESIII drift chamber

    NASA Astrophysics Data System (ADS)

    Ming-Yi, Dong; Qing-Lei, Xiu; Ling-Hui, Wu; Zhi, Wu; Zhong-Hua, Qin; Pin, Shen; Fen-Fen, An; Xu-Dong, Ju; Yi, Liu; Kai, Zhu; Qun, Ou-Yang; Yuan-Bo, Chen

    2016-01-01

    As the main tracking detector of BESIII, the drift chamber provides accurate measurements of the position and the momentum of the charged particles produced in e+e- collisions at BEPCII. After six years of operation, the drift chamber is suffering from aging problems due to huge beam-related background. The gains of the cells in the first ten layers show an obvious decrease, reaching a maximum decrease of about 29% for the first layer cells. Two calculation methods for the gain change (Bhabha events and accumulated charges with 0.3% aging ratio for inner chamber cells) give almost the same results. For the Malter effect encountered by the inner drift chamber in January 2012, about 0.2% water vapor was added to the MDC gas mixture to solve this cathode aging problem. These results provide an important reference for MDC operating high voltage settings and the upgrade of the inner drift chamber. Supported by the CAS Center for Excellence in Particle Physics (CCEPP)

  18. Electron plasma orbits from competing diocotron drifts.

    PubMed

    Hurst, N C; Danielson, J R; Baker, C J; Surko, C M

    2014-07-11

    The perpendicular dynamics of a pure electron plasma column are investigated when the plasma spans two Penning-Malmberg traps with noncoinciding axes. The plasma executes noncircular orbits described by competing image-charge electric-field (diocotron) drifts from the two traps. A simple model is presented that predicts a set of nested orbits in agreement with observed plasma trajectories. PMID:25062198

  19. Toroidal rotation driven by the polarization drift.

    PubMed

    McDevitt, C J; Diamond, P H; Gürcan, O D; Hahm, T S

    2009-11-13

    Starting from a phase space conserving gyrokinetic formulation, a systematic derivation of parallel momentum conservation uncovers a novel mechanism by which microturbulence may drive intrinsic rotation. This mechanism, which appears in the gyrokinetic formulation through the parallel nonlinearity, emerges due to charge separation induced by the polarization drift. The derivation and physical discussion of this mechanism will be pursued throughout this Letter. PMID:20365987

  20. Plate Tectonics and Continental Drift: Classroom Ideas.

    ERIC Educational Resources Information Center

    Stout, Prentice K.

    1983-01-01

    Suggests various classroom studies related to plate tectonics and continental drift, including comments on and sources of resource materials useful in teaching the topics. A complete list of magazine articles on the topics from the Sawyer Marine Resource Collection may be obtained by contacting the author. (JN)

  1. Drift Nets on the High Seas.

    ERIC Educational Resources Information Center

    Clearing, 1990

    1990-01-01

    Information is provided on the use and misuse of drift nets used internationally in the Pacific Ocean. An activity in which students acquire some understanding of the history of fishing and the effects of modern technologies on fish populations is included. (KR)

  2. Drift waves in helically symmetric stellarators

    SciTech Connect

    Rafiq, T.; Hegna, C.

    2005-11-15

    The local linear stability of electron drift waves and ion temperature gradient modes (ITG) is investigated in a quasihelically symmetric (QHS) stellarator and a conventional asymmetric (Mirror) stellarator. The geometric details of the different equilibria are emphasized. Eigenvalue equations for the models are derived using the ballooning mode formalism and solved numerically using a standard shooting technique in a fully three-dimensional stellarator configuration. While the eigenfunctions have a similar shape in both magnetic geometries, they are slightly more localized along the field line in the QHS case. The most unstable electron drift modes are strongly localized at the symmetry points (where stellarator symmetry is present) and in the regions where normal curvature is unfavorable and magnitude of the local magnetic shear and magnetic field is minimum. The presence of a large positive local magnetic shear in the bad curvature region is found to be destabilizing. Electron drift modes are found to be more affected by the normal curvature than by the geodesic curvature. The threshold of stability of the ITG modes in terms of {eta}{sub i} is found to be 2/3 in this fluid model consistent with the smallest threshold for toroidal geometry with adiabatic electrons. Optimization to favorable drift wave stability has small field line curvature, short connection lengths, the proper combination of geodesic curvature and local magnetic shear, large values of local magnetic shear, and the compression of flux surfaces in the unfavorable curvature region.

  3. Unmanned seismometer levels self, corrects drift errors

    NASA Technical Reports Server (NTRS)

    Sutton, G.

    1964-01-01

    Four-component, three-axis, feedback-controlled seismograph incorporates electronic circuitry for leveling and for monitoring the feedback signal required for servo-centering. Viscous damping of the earth-motion signal, compensation of the residual long-term drift, and centering of the seismometers are provided by automatic mechanisms.

  4. Impact of Gene Patents and Licensing Practices on Access to Genetic Testing for Alzheimer’s Disease

    PubMed Central

    Skeehan, Katie; Heaney, Christopher; Cook-Deegan, Robert

    2010-01-01

    Genetic testing for Alzheimer’s disease (AD) includes genotyping for apolipoprotein E, for late-onset AD, and three rare autosomal dominant, early-onset forms of AD associated with different genes (APP, PSEN1 and PSEN2). According to researchers, patents have not impeded research in the field, nor were patents an important consideration in the quest for the genetic risk factors. Athena Diagnostics holds exclusive licenses from Duke University for three “method” patents covering APOE genetic testing. Athena offers tests for APOE and genes associated with early onset, autosomal dominant AD. One of those presenilin genes is patented and exclusively licensed to Athena; the other presenilin gene was patented but the patent was allowed to lapse; and one (APP) is patented only as a research tool and patent claims do not cover diagnostic use. Direct-to-consumer testing is available for some AD-related genes, apparently without a license. Athena Diagnostics consolidated its position in the market for AD genetic testing by collecting exclusive rights to patents arising from university research. Duke University also used its licenses to Athena to enforce adherence to clinical guidelines, including elimination of the service from Smart Genetics, which was offering direct-to-consumer risk assessment based on APOE genotyping. PMID:20393312

  5. Generalization of the one dimensional modeling and design considerations of spiral Si drift detectors: Flat (straight) drift channels and constant drift fields

    NASA Astrophysics Data System (ADS)

    Liu, Manwen; Li, Zheng

    2016-07-01

    The one-dimensional design consideration for the spiral (cylindrical geometry) Si drift detector (SDD) has been modified and generalized for small drift distance (R) compatible to the detector thickness (d), i.e. for R-d, and for non uniform backside biasing situations. By applying a non uniform biasing voltage with a gradient similar (proportional) to the front side, one can increase the reach-through voltage, resulting in a large drift field for carriers. This can be important for large R (>3 mm). With a careful design of electric field profiles on both sides, one can obtain the optimum case of a spiral SDD with a straight (flat) drift channel and constant drift field throughout the carrier drift channel. The previous solution in the literature is an approximation of this work for R»d and with a curved drift channel.

  6. Finding Oxygen Reservoir by Using Extremely Small Test Cell Structure for Resistive Random Access Memory with Replaceable Bottom Electrode

    PubMed Central

    Kinoshita, Kentaro; Koh, Sang-Gyu; Moriyama, Takumi; Kishida, Satoru

    2015-01-01

    Although the presence of an oxygen reservoir (OR) is assumed in many models that explain resistive switching of resistive random access memory (ReRAM) with electrode/metal oxide (MO)/electrode structures, the location of OR is not clear. We have previously reported a method, which involved the use of an AFM cantilever, for preparing an extremely small ReRAM cell that has a removable bottom electrode (BE). In this study, we used this cell structure to specify the location of OR. Because an anode is often assumed to work as OR, we investigated the effect of changing anodes without changing the MO layer and the cathode on the occurrence of reset. It was found that the reset occurred independently of the catalytic ability and Gibbs free energy (ΔG) of the anode. Our proposed structure enabled to determine that the reset was caused by repairing oxygen vacancies of which a filament consists due to the migration of oxygen ions from the surrounding area when high ΔG anode metal is used, whereas by oxidizing the anode due to the migration of oxygen ions from the MO layer when low ΔG anode metal is used, suggesting the location of OR depends on ΔG of the anode. PMID:26689682

  7. Finding Oxygen Reservoir by Using Extremely Small Test Cell Structure for Resistive Random Access Memory with Replaceable Bottom Electrode.

    PubMed

    Kinoshita, Kentaro; Koh, Sang-Gyu; Moriyama, Takumi; Kishida, Satoru

    2015-01-01

    Although the presence of an oxygen reservoir (OR) is assumed in many models that explain resistive switching of resistive random access memory (ReRAM) with electrode/metal oxide (MO)/electrode structures, the location of OR is not clear. We have previously reported a method, which involved the use of an AFM cantilever, for preparing an extremely small ReRAM cell that has a removable bottom electrode (BE). In this study, we used this cell structure to specify the location of OR. Because an anode is often assumed to work as OR, we investigated the effect of changing anodes without changing the MO layer and the cathode on the occurrence of reset. It was found that the reset occurred independently of the catalytic ability and Gibbs free energy (ΔG) of the anode. Our proposed structure enabled to determine that the reset was caused by repairing oxygen vacancies of which a filament consists due to the migration of oxygen ions from the surrounding area when high ΔG anode metal is used, whereas by oxidizing the anode due to the migration of oxygen ions from the MO layer when low ΔG anode metal is used, suggesting the location of OR depends on ΔG of the anode. PMID:26689682

  8. Finding Oxygen Reservoir by Using Extremely Small Test Cell Structure for Resistive Random Access Memory with Replaceable Bottom Electrode

    NASA Astrophysics Data System (ADS)

    Kinoshita, Kentaro; Koh, Sang-Gyu; Moriyama, Takumi; Kishida, Satoru

    2015-12-01

    Although the presence of an oxygen reservoir (OR) is assumed in many models that explain resistive switching of resistive random access memory (ReRAM) with electrode/metal oxide (MO)/electrode structures, the location of OR is not clear. We have previously reported a method, which involved the use of an AFM cantilever, for preparing an extremely small ReRAM cell that has a removable bottom electrode (BE). In this study, we used this cell structure to specify the location of OR. Because an anode is often assumed to work as OR, we investigated the effect of changing anodes without changing the MO layer and the cathode on the occurrence of reset. It was found that the reset occurred independently of the catalytic ability and Gibbs free energy (ΔG) of the anode. Our proposed structure enabled to determine that the reset was caused by repairing oxygen vacancies of which a filament consists due to the migration of oxygen ions from the surrounding area when high ΔG anode metal is used, whereas by oxidizing the anode due to the migration of oxygen ions from the MO layer when low ΔG anode metal is used, suggesting the location of OR depends on ΔG of the anode.

  9. Calculator Access, Use, and Type in Relation to Performance on the SAT I: Reasoning Test in Mathematics.

    ERIC Educational Resources Information Center

    Scheuneman, Janice Dowd; Camara, Wayne J.; Cascallar, Alicia S.; Wendler, Cathy; Lawrence, Ida

    2002-01-01

    Studied the effects of calculator use on performance on the Scholastic Assessment Test I through a questionnaire completed by 202,391 examinees in 1996 and 215,034 in 1997. Use of calculators was associated with higher performance, but the more able students were more likely to have calculators. Overall, the effects of calculators were found to be…

  10. Evaluating Public Access On-Line Catalogs. Phase I: Development and Testing of Data Collection and Analysis Tools. Final Report.

    ERIC Educational Resources Information Center

    Larson, Ray R.

    This report outlines specifications for the online transaction monitoring and questionnaire administration features of the University of California's (UC) Prototype On-Line Catalog, known as MELVYL. The development and testing of these features by the UC Division of Library Automation (DLA) is also described. This document is the final report…

  11. The Effects of Clock Drift on the Mars Exploration Rovers

    NASA Technical Reports Server (NTRS)

    Ali, Khaled S.; Vanelli, C. Anthony

    2012-01-01

    All clocks drift by some amount, and the mission clock on the Mars Exploration Rovers (MER) is no exception. The mission clock on both MER rovers drifted significantly since the rovers were launched, and it is still drifting on the Opportunity rover. The drift rate is temperature dependent. Clock drift causes problems for onboard behaviors and spacecraft operations, such as attitude estimation, driving, operation of the robotic arm, pointing for imaging, power analysis, and telecom analysis. The MER operations team has techniques to deal with some of these problems. There are a few techniques for reducing and eliminating the clock drift, but each has drawbacks. This paper presents an explanation of what is meant by clock drift on the rovers, its relationship to temperature, how we measure it, what problems it causes, how we deal with those problems, and techniques for reducing the drift.

  12. An Augmented SMS Intervention to Improve Access to Antenatal CD4 Testing and ART Initiation in HIV-Infected Pregnant Women: A Cluster Randomized Trial

    PubMed Central

    Dryden-Peterson, Scott; Bennett, Kara; Hughes, Michael D.; Veres, Adrian; John, Oaitse; Pradhananga, Rosina; Boyer, Matthew; Brown, Carolyn; Sakyi, Bright; van Widenfelt, Erik; Keapoletswe, Koona; Mine, Madisa; Moyo, Sikhulile; Asmelash, Aida; Siedner, Mark; Mmalane, Mompati; Shapiro, Roger L.; Lockman, Shahin

    2015-01-01

    Background Less than one-third of HIV-infected pregnant women eligible for combination antiretroviral therapy (ART) globally initiate treatment prior to delivery, with lack of access to timely CD4 results being a principal barrier. We evaluated the effectiveness of an SMS-based intervention to improve access to timely antenatal ART. Methods We conducted a stepped-wedge cluster randomized trial of a low-cost programmatic intervention in 20 antenatal clinics in Gaborone, Botswana. From July 2011-April 2012, 2 clinics were randomly selected every 4 weeks to receive an ongoing clinic-based educational intervention to improve CD4 collection and to receive CD4 results via an automated SMS platform with active patient tracing. CD4 testing before 26 weeks gestation and ART initiation before 30 weeks gestation were assessed. Results Three-hundred-sixty-six ART-naïve women were included, 189 registering for antenatal care under Intervention and 177 under Usual Care periods. Of CD4-eligible women, 100 (59.2%) women under Intervention and 79 (50.6%) women under Usual Care completed CD4 phlebotomy before 26 weeks gestation, adjusted odds ratio (aOR, adjusted for time that a clinic initiated Intervention) 0.87 (95% confidence interval [CI]0.47–1.63, P = 0.67). The SMS-based platform reduced time to clinic receipt of CD4 test result from median of 16 to 6 days (P<0.001), was appreciated by clinic staff, and was associated with reduced operational cost. However, rates of ART initiation remained low, with 56 (36.4%) women registering under Intervention versus 37 (24.2%) women under Usual Care initiating ART prior to 30 weeks gestation, aOR 1.06 (95%CI 0.53–2.13, P = 0.87). Conclusions The augmented SMS-based intervention delivered CD4 results more rapidly and efficiently, and this type of SMS-based results delivery platform may be useful for a variety of tests and settings. However, the intervention did not appear to improve access to timely antenatal CD4 testing or ART

  13. Wind tunnel evaluation of several tracer and collection techniques for the measurement of spray drift.

    PubMed

    Brusselman, E; Van Driessen, K; Steurbaut, W; Gabriels, D; Cornelis, W; Nuyttens, D; Sonck, B; Baetens, K; Nicolai, B; Verboven, P; Ramon, H

    2004-01-01

    In the history of pesticide drift measuring techniques, different tracers and a lot of different collection techniques have been used. At the start of a new Flemish project 'Protecting the Flemish environment against drift - The importance of drift-reducing techniques', wind tunnel tests have been executed to select the most efficient tracer and collection technique. As tracer types a fluorescent tracer Renaissance W15, 2 different chelates, a NaCl-solution and a fungicide Tolylfluanide were used. 2 different collection techniques were tested: drains incorporated in the wind tunnel floor filled with filter paper and filled with cloths. The recovery of the different tracers combined with the 2 collection materials was calculated. The advantages and disadvantages of the tracers and collection materials are enumerated in this article. PMID:15756877

  14. Self-Attractive Random Walks: The Case of Critical Drifts

    NASA Astrophysics Data System (ADS)

    Ioffe, Dmitry; Velenik, Yvan

    2012-07-01

    Self-attractive random walks (polymers) undergo a phase transition in terms of the applied drift (force): If the drift is strong enough, then the walk is ballistic, whereas in the case of small drifts self-attraction wins and the walk is sub-ballistic. We show that, in any dimension d ≥ 2, this transition is of first order. In fact, we prove that the walk is already ballistic at critical drifts, and establish the corresponding LLN and CLT.

  15. Longevity of Emplacement Drift Ground Support Materials

    SciTech Connect

    Tang, David H.

    2001-05-30

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for the selection of materials for ground support that will function throughout the preclosure period of a potential repository at Yucca Mountain. REV 01 ICN 01 of this analysis is developed in accordance with AP-3.10Q, Analyses and Models, Revision 2, ICN 4, and prepared in accordance with the Technical Work Plan for Subsurface Design Section FY 01 Work Activities (CRWMS M&O 2001a). The objective of this analysis is to update the previous analysis (CRWMS M&O 2000a) to account for related changes in the Ground Control System Description Document (CRWMS M&O 2000b), the Monitored Geologic Repository Project Description Document, which is included in the Requirements and Criteria for Implementing a Repository Design that can be Operated Over a Range of Thermal Modes (BSC 2001), input information, and in environmental conditions, and to provide updated information on candidate ground support materials. Candidate materials for ground support are carbon steel and cement grout. Steel is mainly used for steel sets, lagging, channel, rock bolts, and wire mesh. Cement grout is only considered in the case of grouted rock bolts. Candidate materials for the emplacement drift invert are carbon steel and granular natural material. Materials are evaluated for the repository emplacement drift environment based on the updated thermal loading condition and waste package design. The analysis consists of the following tasks: (1) Identify factors affecting the longevity of ground support materials for use in emplacement drifts. (2) Review existing documents concerning the behavior of candidate ground support materials during the preclosure period. (3) Evaluate impacts of temperature and radiation effects on mechanical and thermal properties of steel. Assess corrosion potential of steel at emplacement drift environment. (4) Evaluate factors

  16. 40 CFR 158.1100 - Spray drift data requirements table.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Spray drift data requirements table. 158.1100 Section 158.1100 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Spray Drift § 158.1100 Spray drift data requirements table. (a) General. Sections 158.100...

  17. 40 CFR 158.1100 - Spray drift data requirements table.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Spray drift data requirements table. 158.1100 Section 158.1100 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Spray Drift § 158.1100 Spray drift data requirements table. (a) General. Sections 158.100...

  18. Effectiveness of spray adjuvants on reduction of spray drift

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous drift reduction adjuvants and spray deposition aids are available to applicators of crop production and protection chemicals. Performance of many of the newly introduced drift control adjuvants has not been well documented for aerial application. Five new drift control adjuvants were sele...

  19. DRIFTSIM, A Computer Program for Estimating Spray Drift Distances

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the severe problems with spraying pesticides is the spray drift. Drift is a problem if chemicals are sprayed too close to residential areas, livestock facilities, bodies of water, or sensitive crops. Complaints regarding spray drift are routinely brought to state departments of agriculture,...

  20. Web Accessibility and Accessibility Instruction

    ERIC Educational Resources Information Center

    Green, Ravonne A.; Huprich, Julia

    2009-01-01

    Section 508 of the Americans with Disabilities Act (ADA) mandates that programs and services be accessible to people with disabilities. While schools of library and information science (SLIS*) and university libraries should model accessible Web sites, this may not be the case. This article examines previous studies about the Web accessibility of…

  1. Electromagnetic nonlinear gyrokinetics with polarization drift

    SciTech Connect

    Duthoit, F.-X.; Hahm, T. S.; Wang, Lu

    2014-08-15

    A set of new nonlinear electromagnetic gyrokinetic Vlasov equation with polarization drift and gyrokinetic Maxwell equations is systematically derived by using the Lie-transform perturbation method in toroidal geometry. For the first time, we recover the drift-kinetic expression for parallel acceleration [R. M. Kulsrud, in Basic Plasma Physics, edited by A. A. Galeev and R. N. Sudan (North-Holland, Amsterdam, 1983)] from the nonlinear gyrokinetic equations, thereby bridging a gap between the two formulations. This formalism should be useful in addressing nonlinear ion Compton scattering of intermediate-mode-number toroidal Alfvén eigenmodes for which the polarization current nonlinearity [T. S. Hahm and L. Chen, Phys. Rev. Lett. 74, 266 (1995)] and the usual finite Larmor radius effects should compete.

  2. Gas sensor with attenuated drift characteristic

    DOEpatents

    Chen, Ing-Shin [Danbury, CT; Chen, Philip S. H. [Bethel, CT; Neuner, Jeffrey W [Bethel, CT; Welch, James [Fairfield, CT; Hendrix, Bryan [Danbury, CT; Dimeo, Jr., Frank [Danbury, CT

    2008-05-13

    A sensor with an attenuated drift characteristic, including a layer structure in which a sensing layer has a layer of diffusional barrier material on at least one of its faces. The sensor may for example be constituted as a hydrogen gas sensor including a palladium/yttrium layer structure formed on a micro-hotplate base, with a chromium barrier layer between the yttrium layer and the micro-hotplate, and with a tantalum barrier layer between the yttrium layer and an overlying palladium protective layer. The gas sensor is useful for detection of a target gas in environments susceptible to generation or incursion of such gas, and achieves substantial (e.g., >90%) reduction of signal drift from the gas sensor in extended operation, relative to a corresponding gas sensor lacking the diffusional barrier structure of the invention

  3. Non-Neutral Drift Resonance in Magnetrons

    NASA Astrophysics Data System (ADS)

    Kaup, D. J.

    2005-04-01

    We study the features of the RF fields in a magnetron, when the RF amplitude has saturated, in the nonrelativistic, electrostatic limit. In this saturated stage, the linear RF equations can be reduced to a fifth-order set of ordinary differential equations. Two modes of which are fast cyclotron modes, one mode is a fast drift wave, and the other two modes are the usual, well-known, slow magnetron modes. Here, we will study the interaction between the fast drift mode (diocotron mode) and the slow magnetron modes, at the diocotron resonance. We will also show that the fast cyclotron modes can be ignored at this resonance, and thereby can reduce the system to a third- order set of ordinary differential equations. Using multiscale techniques, we will then obtain solutions for the inner and the outer regions at the diocotron resonance, and thereby obtain the conversion and transmission rates between these three modes at the diocotron resonance.

  4. Coupled-cavity drift-tube linac

    DOEpatents

    Billen, J.H.

    1996-11-26

    A coupled-cavity drift-tube linac (CCDTL) combines features of the Alvarez drift-tube linac (DTL) and the {pi}-mode coupled-cavity linac (CCL). In one embodiment, each accelerating cavity is a two-cell, 0-mode DTL. The center-to-center distance between accelerating gaps is {beta}{lambda}, where {lambda} is the free-space wavelength of the resonant mode. Adjacent accelerating cavities have oppositely directed electric fields, alternating in phase by 180 degrees. The chain of cavities operates in a {pi}/2 structure mode so the coupling cavities are nominally unexcited. The CCDTL configuration provides an rf structure with high shunt impedance for intermediate velocity charged particles, i.e., particles with energies in the 20-200 MeV range. 5 figs.

  5. Coupled-cavity drift-tube linac

    DOEpatents

    Billen, James H.

    1996-01-01

    A coupled-cavity drift-tube linac (CCDTL) combines features of the Alvarez drift-tube linac (DTL) and the .pi.-mode coupled-cavity linac (CCL). In one embodiment, each accelerating cavity is a two-cell, 0-mode DTL. The center-to-center distance between accelerating gaps is .beta..lambda., where .lambda. is the free-space wavelength of the resonant mode. Adjacent accelerating cavities have oppositely directed electric fields, alternating in phase by 180 degrees. The chain of cavities operates in a .pi./2 structure mode so the coupling cavities are nominally unexcited. The CCDTL configuration provides an rf structure with high shunt impedance for intermediate velocity charged particles, i.e., particles with energies in the 20-200 MeV range.

  6. Passive appendages generate drift through symmetry breaking

    NASA Astrophysics Data System (ADS)

    Lācis, U.; Brosse, N.; Ingremeau, F.; Mazzino, A.; Lundell, F.; Kellay, H.; Bagheri, S.

    2014-10-01

    Plants and animals use plumes, barbs, tails, feathers, hairs and fins to aid locomotion. Many of these appendages are not actively controlled, instead they have to interact passively with the surrounding fluid to generate motion. Here, we use theory, experiments and numerical simulations to show that an object with a protrusion in a separated flow drifts sideways by exploiting a symmetry-breaking instability similar to the instability of an inverted pendulum. Our model explains why the straight position of an appendage in a fluid flow is unstable and how it stabilizes either to the left or right of the incoming flow direction. It is plausible that organisms with appendages in a separated flow use this newly discovered mechanism for locomotion; examples include the drift of plumed seeds without wind and the passive reorientation of motile animals.

  7. Chandra Optical Axis, Aimpoint and Their Drifts

    NASA Astrophysics Data System (ADS)

    Zhao, Ping

    2014-08-01

    Chandra X-ray Observatory revolutionized the X-ray astronomy as being the first, and so far the only, X-ray telescope achieving sub-arcsecond resolution. Chandra comprises of three principal elements: the High Resolution Mirror Assembly (HRMA), Pointing Control and Aspect Determination (PCAD) system, and the Science Instrument Module (SIM). To achieve and retain the unprecedented imaging quality, it is critical that these three principal elements stay rigid and stable for the entire life time of the Chandra operation. Measuring and tracking the telescope optical axis and aimpoint positions are the key to understand the stability of the telescope and to maintain the optimal Chandra operation. The study shows that both the optical axis and the aimpoint has been drifting since Chandra launch. I will review the history and current status of these drift and their impact to the Chandra operation, as well as the steps we took to ensure the Chandra science returns.

  8. Ocular drift along the mental number line.

    PubMed

    Myachykov, Andriy; Ellis, Rob; Cangelosi, Angelo; Fischer, Martin H

    2016-05-01

    We examined the spontaneous association between numbers and space by documenting attention deployment and the time course of associated spatial-numerical mapping with and without overt oculomotor responses. In Experiment 1, participants maintained central fixation while listening to number names. In Experiment 2, they made horizontal target-direct saccades following auditory number presentation. In both experiments, we continuously measured spontaneous ocular drift in horizontal space during and after number presentation. Experiment 2 also measured visual-probe-directed saccades following number presentation. Reliable ocular drift congruent with a horizontal mental number line emerged during and after number presentation in both experiments. Our results provide new evidence for the implicit and automatic nature of the oculomotor resonance effect associated with the horizontal spatial-numerical mapping mechanism. PMID:26724955

  9. Electromagnetic nonlinear gyrokinetics with polarization drift

    NASA Astrophysics Data System (ADS)

    Duthoit, F.-X.; Hahm, T. S.; Wang, Lu

    2014-08-01

    A set of new nonlinear electromagnetic gyrokinetic Vlasov equation with polarization drift and gyrokinetic Maxwell equations is systematically derived by using the Lie-transform perturbation method in toroidal geometry. For the first time, we recover the drift-kinetic expression for parallel acceleration [R. M. Kulsrud, in Basic Plasma Physics, edited by A. A. Galeev and R. N. Sudan (North-Holland, Amsterdam, 1983)] from the nonlinear gyrokinetic equations, thereby bridging a gap between the two formulations. This formalism should be useful in addressing nonlinear ion Compton scattering of intermediate-mode-number toroidal Alfvén eigenmodes for which the polarization current nonlinearity [T. S. Hahm and L. Chen, Phys. Rev. Lett. 74, 266 (1995)] and the usual finite Larmor radius effects should compete.

  10. Passive appendages generate drift through symmetry breaking.

    PubMed

    Lācis, U; Brosse, N; Ingremeau, F; Mazzino, A; Lundell, F; Kellay, H; Bagheri, S

    2014-01-01

    Plants and animals use plumes, barbs, tails, feathers, hairs and fins to aid locomotion. Many of these appendages are not actively controlled, instead they have to interact passively with the surrounding fluid to generate motion. Here, we use theory, experiments and numerical simulations to show that an object with a protrusion in a separated flow drifts sideways by exploiting a symmetry-breaking instability similar to the instability of an inverted pendulum. Our model explains why the straight position of an appendage in a fluid flow is unstable and how it stabilizes either to the left or right of the incoming flow direction. It is plausible that organisms with appendages in a separated flow use this newly discovered mechanism for locomotion; examples include the drift of plumed seeds without wind and the passive reorientation of motile animals. PMID:25354545

  11. Bottle appeal drifts across the Pacific

    NASA Astrophysics Data System (ADS)

    Ebbesmeyer, Curtis; Ingraham, W. James, Jr.; McKinnon, Richard; Okubo, Akira; Wang, Dong-Ping; Strickland, Richard; Willing, Peter

    Pacific drift currents were used by a group of oceanographers to estimate the path of a drift bottle that was found on a beach of Barkley Sound in Vancouver Island by Richard Strickland on June 10, 1990. The Chinese rice wine bottle, which remained unopened until December 18, 1991, contained six leaflets, one appealing for the release of China's well-known dissident, Wei Jingsheng. The bottle was one of thousands set adrift as part of a propaganda effort from the islands of Quemoy and Matsu off mainland China shortly after Wei was sentenced in 1979 to 15 years in prison (see Figure 1 for locations). Wei was in poor health and still in prison when the bottle made its way across the Pacific Ocean.

  12. Passive appendages generate drift through symmetry breaking

    PubMed Central

    Lācis, U.; Brosse, N.; Ingremeau, F.; Mazzino, A.; Lundell, F.; Kellay, H.; Bagheri, S.

    2014-01-01

    Plants and animals use plumes, barbs, tails, feathers, hairs and fins to aid locomotion. Many of these appendages are not actively controlled, instead they have to interact passively with the surrounding fluid to generate motion. Here, we use theory, experiments and numerical simulations to show that an object with a protrusion in a separated flow drifts sideways by exploiting a symmetry-breaking instability similar to the instability of an inverted pendulum. Our model explains why the straight position of an appendage in a fluid flow is unstable and how it stabilizes either to the left or right of the incoming flow direction. It is plausible that organisms with appendages in a separated flow use this newly discovered mechanism for locomotion; examples include the drift of plumed seeds without wind and the passive reorientation of motile animals. PMID:25354545

  13. Longevity of emplacement drift ground support materials

    SciTech Connect

    Tang, David

    2000-04-01

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for the selection of materials for ground support that will function throughout the preclosure period of a potential repository at Yucca Mountain. The Development Plan (DP) for this analysis is given in Longevity of Emplacement Drift Ground Support Materials (CRWMS M and O 1999a). The objective of this analysis is to update the previous analysis (CRWMS M and O 2000a) to account for related changes in the Ground Control System Description Document (CRWMS M and O 2000b), the Monitored Geologic Repository Project Description Document (CRWMS M and O 1999b), and in environmental conditions, and to provide updated information on candidate ground support materials.

  14. Drift Phenomena of Forward and Reverse Recovery Characteristics in 0001 4H-SiC p-i-n Diode

    NASA Astrophysics Data System (ADS)

    Nakayama, Koji; Sugawara, Yoshitaka; Tsuchida, Hidekazu; Kimura, Chiharu; Aoki, Hidemitsu

    2011-04-01

    4H-SiC p-i-n diodes fabricated on the (0001) C-face showed smaller forward voltage drift and minimal changes in reverse recovery characteristics after a forward bias stress test compared to those observed on the (0001) Si-face. These drift phenomena in 4H-SiC p-i-n diodes could be explained by increased recombination along the perimeter of single Shockley-type stacking faults. It is suggested that the number of single Shockley-type stacking faults significantly decreased in the drift layer fabricated on (0001) C-face in comparison with that on (0001) Si-face.

  15. A future for drifting seismic networks

    NASA Astrophysics Data System (ADS)

    Simons, F. J.; Nolet, G.; Babcock, J.

    2007-12-01

    One-dimensional, radial Earth models are sufficiently well constrained to accurately locate earthquakes and calculate the paths followed by seismic rays. The differences between observations and theoretical predictions of seismograms in such Earth models can be used to reconstruct the three-dimensional wave speed distribution in the regions sampled by the seismic waves, by the technique of seismic tomography. Caused by thermal, compositional, and textural variations, wave speed anomalies remain the premier data source to fully understand the structure and evolution of our planet, from the scale of mantle convection and the mechanisms of heat transfer from core to surface to the international between the deep Earth and surface processes such as plate motion and crustal deformation. Unequal geographical data coverage continues to fundamentally limit the quality of tomographic reconstructions of seismic wave speeds in the interior of the Earth. Only at great cost can geophysicists overcome the difficulties of placing seismographs on the two thirds of the Earth's surface that is covered by oceans. The lack of spatial data coverage strongly hampers the determination of the structure of the Earth in the uncovered regions: all 3-D Earth models are marked by blank spots in areas, distributed throughout the Earth, where little or no information can be obtained. As a possible solution to gaining equal geographic data coverage, we have developed MERMAID, a prototype mobile receiver that could provide an easy, cost-effective way to collect seismic data in the ocean. It is a modification of the robotic floating instruments designed and used by oceanographers. Like them, MERMAID spends its life at depth but is capable of surfacing using a pump and bladder. We have equipped it with a hydrophone to record water pressure variations induced by compressional (P) waves. Untethered and passively drifting, such a floating seismometer will surface upon detection of a "useful" seismic

  16. Inertial Orientation Trackers with Drift Compensation

    NASA Technical Reports Server (NTRS)

    Foxlin, Eric M.

    2008-01-01

    A class of inertial-sensor systems with drift compensation has been invented for use in measuring the orientations of human heads (and perhaps other, similarly sized objects). These systems can be designed to overcome some of the limitations of prior orientation-measuring systems that are based, variously, on magnetic, optical, mechanical-linkage, and acoustical principles. The orientation signals generated by the systems of this invention could be used for diverse purposes, including controlling head-orientation-dependent virtual reality visual displays or enabling persons whose limbs are paralyzed to control machinery by means of head motions. The inventive concept admits to variations too numerous to describe here, making it necessary to limit this description to a typical system, the selected aspects of which are illustrated in the figure. A set of sensors is mounted on a bracket on a band or a cap that gently but firmly grips the wearer s head to be tracked. Among the sensors are three drift-sensitive rotationrate sensors (e.g., integrated-circuit angular- rate-measuring gyroscopes), which put out DC voltages nominally proportional to the rates of rotation about their sensory axes. These sensors are mounted in mutually orthogonal orientations for measuring rates of rotation about the roll, pitch, and yaw axes of the wearer s head. The outputs of these rate sensors are conditioned and digitized, and the resulting data are fed to an integrator module implemented in software in a digital computer. In the integrator module, the angular-rate signals are jointly integrated by any of several established methods to obtain a set of angles that represent approximately the orientation of the head in an external, inertial coordinate system. Because some drift is always present as a component of an angular position computed by integrating the outputs of angular-rate sensors, the orientation signal is processed further in a drift-compensator software module.

  17. Drift in interference filters. Part 1.

    PubMed

    Title, A M; Pope, T P; Andelin, J P

    1974-11-01

    Studies of narrow-band interference filters have shown that two mechanisms exist that cause drift to shorter wavelengths. One is dependent on the thermal history of the filter, and the other depends on the radiation history. The present paper presents experimental results on thermal effects; and it is shown that by a proper bake cycle, ZnS-cryolite filters are stable for years if stored at less than 38 degrees C. PMID:20134753

  18. Drift Resonance in High Density Nonneutral Plasmas

    NASA Astrophysics Data System (ADS)

    Kaup, D. J.

    2005-10-01

    Theoretical studies of the operation of crossed-field electron vacuum devices, such as magnetrons and crossed-field amplifiers (CFA), have usually centered on their initial growth, taking this as an indication of their operating modes. In such an analysis, one solves the equations for the density profile and other features of these devices. However what one actually obtains are only the conditions for the initial operation of the device. Eventually the rf fields will saturate, at which time, an operating device will settle into a stationary operating regime, called the ``saturation stage,'' which is where the device simply delivers rf power. Here there is a different set of physical interactions occuring. The amplitudes have saturated and the ponderomotive forces and nonlinear diffusion of the initiation stage have vanished. In this saturation stage, we now find three new rf modes appearing, in addition to the two modes of the initiation stage. These three new modes have very fast oscillations in the vertical direction: one fast mode corresponds to a plasma drift wave, while the other two fast modes are cyclotron-like modes. In this presentation, we will describe how the fast plasma drift wave interacts with the slow modes at the diocotron resonance. In particular, we will determine the conversion coefficients for the crossing of the drift mode with the slow modes at the diocotron resonance.

  19. Causal Drift, Robust Signaling, and Complex Disease

    PubMed Central

    Wagner, Andreas

    2015-01-01

    The phenotype of many regulatory circuits in which mutations can cause complex, polygenic diseases is to some extent robust to DNA mutations that affect circuit components. Here I demonstrate how such mutational robustness can prevent the discovery of genetic disease determinants. To make my case, I use a mathematical model of the insulin signaling pathway implicated in type 2 diabetes, whose signaling output is governed by 15 genetically determined parameters. Using multiple complementary measures of a parameter’s importance for this phenotype, I show that any one disease determinant that is crucial in one genetic background will be virtually irrelevant in other backgrounds. In an evolving population that drifts through the parameter space of this or other robust circuits through DNA mutations, the genetic changes that can cause disease will vary randomly over time. I call this phenomenon causal drift. It means that mutations causing disease in one (human or non-human) population may have no effect in another population, and vice versa. Causal drift casts doubt on our ability to infer the molecular mechanisms of complex diseases from non-human model organisms. PMID:25774510

  20. Sunrise enhancement of equatorial vertical plasma drift

    NASA Astrophysics Data System (ADS)

    Liu, Libo; Zhang, Ruilong; Le, Huijun

    2016-04-01

    Sunrise enhancement in vertical plasma drift over equatorial regions is not discernible in the statistical picture compared with the significant enhancement during dusk hours. In this report, it is the first time to investigate the occurrence of the dawn enhancement in the equatorial ionospheric vertical plasma drift from ROCSAT-1 observations during geomagnetic quiet times. The dawn enhancements occur most frequently in June solstice and least frequently in December solstice. The statistical survey shows that the occurrence depends on the magnetic declination. The enhancement has the strongest amplitude in regions near 320° longitude and peaks during June solstice. The dawn enhancement reaches its peak after the sunrise in conjugated E regions. Furthermore, it is found that the dawn enhancement is closely related to the difference between the sunrise times in the conjugated E regions (sunrise time lag). The dawn enhancement occurs easily in regions with a large sunrise time lag. Moreover, we will report the effects of the sunrise enhancement of vertical plasma drift on the equatorial ionosphere as indicated from the observations and model simulations. We thanks National Central University of Taiwan providing the ROCSAT-1 data. The Ap and F107 indices are obtained from the National Geophysical Data Center (http://spidr.ngdc.noaa.gov/spidr/). This research is supported by National Natural Science Foundation of China (41231065), the Chinese Academy of Sciences project (KZZD-EW-01-3), National Key Basic Research Program of China (2012CB825604) and National Natural Science Foundation of China (41321003).

  1. Longevity of Emplacement Drift Ground Support Materials

    SciTech Connect

    D. Tang

    2000-01-07

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for selection of materials for ground support that will function throughout the preclosure period. The Development Plan (DP) for this analysis is given in CRWMS M&O (Civilian Radioactive Waste Management System Management and Operating Contractor) (1999a). The candidate materials for ground support are steel (carbon steel, ductile cast iron, galvanized steel, and stainless steel, etc.) and cement. Steel will mainly be used for steel sets, lagging, channels, rock bolts, and wire mesh. Cement usage is only considered in the case of grouted rock bolts. The candidate materials for the invert structure are steel and crushed rock ballast. The materials shall be evaluated for the repository emplacement drift environment under a specific thermal loading condition based on the proposed License Application Design Selection (LADS) design. The analysis consists of the following tasks: (1) Identify factors affecting the longevity of ground control materials for use in emplacement drifts. (2) Review existing documents concerning behavior of candidate ground control materials during the preclosure period. The major criteria to be considered for steel are mechanical and thermal properties, and durability, of which corrosion is the most important concern. (3) Evaluate the available results and develop recommendations for material(s) to be used.

  2. Wind tunnel observations of drifting snow

    NASA Astrophysics Data System (ADS)

    Paterna, Enrico; Crivelli, Philip; Lehning, Michael

    2016-04-01

    Drifting snow has a significant impact on snow redistribution in mountains, prairies as well as on glaciers, ice shelves, and sea ice. In all these environments, the local mass balance is highly influenced by drifting snow. Understanding the dynamic of snow saltation is crucial to the accurate description of the process. We applied digital shadowgraphy in a cold wind tunnel to measure drifting snow over natural snow covers. The acquisition and evaluation of time-resolved shadowgraphy images allowed us to resolve a large part of the saltation layer. The technique has been successfully compared to the measurements obtained from a Snow Particle Counter, considered the most robust technique for snow mass-flux measurements so far. The streamwise snow transport is dominated by large-scale events. The vertical snow transport has a more equal distribution of energy across the scales, similarly to what is observed for the flow turbulence velocities. It is hypothesized that the vertical snow transport is a quantity that reflects the local entrainment of the snow crystals into the saltation layer while the streamwise snow transport results from the streamwise development of the trajectories of the snow particles once entrained, and therefore is rather a non-local quantity.

  3. Access to Diagnostic Tests and Essential Medicines for Cardiovascular Diseases and Diabetes Care: Cost, Availability and Affordability in the West Region of Cameroon

    PubMed Central

    Jingi, Ahmadou M.; Noubiap, Jean Jacques N.; Ewane Onana, Arnold; Nansseu, Jobert Richie N.; Wang, Binhuan; Kingue, Samuel; Kengne, André Pascal

    2014-01-01

    Objective To assess the availability and affordability of medicines and routine tests for cardiovascular disease (CVD) and diabetes in the West region of Cameroon, a low-income setting. Methods A survey was conducted on the availability and cost of twelve routine tests and twenty medicines for CVD and diabetes in eight health districts (four urban and four rural) covering over 60% of the population of the region (1.8 million). We analyzed the percentage of tests and medicines available, the median price against the international reference price (median price ratio) for the medicines, and affordability in terms of the number of days’ wages it would cost the lowest-paid unskilled government worker for initial investigation tests and procurement for one month of treatment. Results The availability of tests varied between 10% for the ECG to 100% for the fasting blood sugar. The average cost for the initial investigation using the minimum tests cost 29.76 days’ wages. The availability of medicines varied from 36.4% to 59.1% in urban and from 9.1% to 50% in rural settings. Only metformin and benzathine-benzylpenicilline had a median price ratio of ≤1.5, with statins being largely unaffordable (at least 30.51 days’ wages). One month of combination treatment for coronary heart disease costs at least 40.87 days’ wages. Conclusion The investigation and management of patients with medium-to-high cardiovascular risk remains largely unavailable and unaffordable in this setting. An effective non-communicable disease program should lay emphasis on primary prevention, and improve affordable access to essential medicines in public outlets. PMID:25369455

  4. Prospective assessment of rapid diagnostic tests for the detection of antibodies to hepatitis C virus, a tool for improving access to care.

    PubMed

    Chevaliez, S; Poiteau, L; Rosa, I; Soulier, A; Roudot-Thoraval, F; Laperche, S; Hézode, C; Pawlotsky, J-M

    2016-05-01

    Large-scale hepatitis C screening is required to prevent further spread of the infection, improve access to care in the context of new hepatitis C virus (HCV) drug regimens without interferon-alpha and subsequently reduce the risk of long-term complications of chronic liver disease. Rapid diagnostic tests (RDTs) represent an attractive alternative to enzyme immunoassay using blood from venepuncture. The aim of the present study was to prospectively assess the clinical performance of CE-marked RDTs detecting anti-HCV antibodies in fingerstick capillary whole blood and/or oral fluid. A total of 513 individuals, including 318 patients with chronic HCV infection, 25 patients with resolved HCV infection and 170 HCV-seronegative individuals, were prospectively enrolled. The specificity of RDTs with fingerstick whole blood varied from 98.8% to 100%. The clinical sensitivity was high for the OraQuick(®) and Toyo(®) tests (99.4% and 95.8%, respectively), but low for the Labmen(®) test (63.1%). The specificity and clinical sensitivity in crevicular fluid were both satisfactory for the OraQuick(®) test (100% and 97.6%, respectively). HCV antibody RDTs were easy and rapid to perform in the context of patient care. They were highly specific. Both the OraQuick(®) and Toyo(®) tests reached the expected level of performance for wide-scale use, with a performance advantage for the OraQuick(®) HCV test. RDTs appear to be a promising new tool for wide-scale screening of HCV infection in high-risk to medium-risk populations. Hence, careful assessment of the performance of HCV RDTs must be recommended before they can be implemented in clinical practice. PMID:26806260

  5. Access to Healthcare, HIV/STI Testing, and Preferred Pre-Exposure Prophylaxis Providers among Men Who Have Sex with Men and Men Who Engage in Street-Based Sex Work in the US

    PubMed Central

    Underhill, Kristen; Morrow, Kathleen M.; Colleran, Christopher M.; Holcomb, Richard; Operario, Don; Calabrese, Sarah K.; Galárraga, Omar; Mayer, Kenneth H.

    2014-01-01

    Background Pre-exposure prophylaxis (PrEP) is a promising strategy for HIV prevention among men who have sex with men (MSM) and men who engage in sex work. But access will require routine HIV testing and contacts with healthcare providers. This study investigated men’s healthcare and HIV testing experiences to inform PrEP implementation. Methods We conducted 8 focus groups (n = 38) in 2012 and 56 in-depth qualitative interviews in 2013–14 with male sex workers (MSWs) (n = 31) and other MSM (n = 25) in Providence, RI. MSWs primarily met clients in street-based sex work venues. Facilitators asked participants about access to healthcare and HIV/STI testing, healthcare needs, and preferred PrEP providers. Results MSWs primarily accessed care in emergency rooms (ERs), substance use clinics, correctional institutions, and walk-in clinics. Rates of HIV testing were high, but MSWs reported low access to other STI testing, low insurance coverage, and unmet healthcare needs including primary care, substance use treatment, and mental health services. MSM not engaging in sex work were more likely to report access to primary and specialist care. Rates of HIV testing among these MSM were slightly lower, but they reported more STI testing, more insurance coverage, and fewer unmet needs. Preferred PrEP providers for both groups included primary care physicians, infectious disease specialists, and psychiatrists. MSWs were also willing to access PrEP in substance use treatment and ER settings. Conclusions PrEP outreach efforts for MSWs and other MSM should engage diverse providers in many settings, including mental health and substance use treatment, ERs, needle exchanges, correctional institutions, and HIV testing centers. Access to PrEP will require financial assistance, but can build on existing healthcare contacts for both populations. PMID:25386746

  6. Gas analyzer's drift leads to systematic error in maximal oxygen uptake and maximal respiratory exchange ratio determination

    PubMed Central

    Garcia-Tabar, Ibai; Eclache, Jean P.; Aramendi, José F.; Gorostiaga, Esteban M.

    2015-01-01

    The aim was to examine the drift in the measurements of fractional concentration of oxygen (FO2) and carbon dioxide (FCO2) of a Nafion-using metabolic cart during incremental maximal exercise in 18 young and 12 elderly males, and to propose a way in which the drift can be corrected. The drift was verified by comparing the pre-test calibration values with the immediate post-test verification values of the calibration gases. The system demonstrated an average downscale drift (P < 0.001) in FO2 and FCO2 of −0.18% and −0.05%, respectively. Compared with measured values, corrected average maximal oxygen uptakevalues were 5–6% lower (P < 0.001) whereas corrected maximal respiratory exchange ratio values were 8–9% higher (P < 0.001). The drift was not due to an electronic instability in the analyzers because it was reverted after 20 min of recovery from the end of the exercise. The drift may be related to an incomplete removal of water vapor from the expired gas during transit through the Nafion conducting tube. These data demonstrate the importance of checking FO2 and FCO2 values by regular pre-test calibrations and post-test verifications, and also the importance of correcting a possible shift immediately after exercise. PMID:26578980

  7. Ground Control for Emplacement Drifts for SR

    SciTech Connect

    Y. Sun

    2000-04-07

    This analysis demonstrates that a satisfactory ground control system can be designed for the Yucca Mountain site, and provides the technical basis for the design of ground support systems to be used in repository emplacement and non-emplacement drifts. The repository ground support design was based on analytical methods using acquired computer codes, and focused on the final support systems. A literature review of case histories, including the lessons learned from the design and construction of the ESF, the studies on the seismic damages of underground openings, and the use of rock mass classification systems in the ground support design, was conducted (Sections 6.3.4 and 6.4). This review provided some basis for determining the inputs and methodologies used in this analysis. Stability of the supported and unsupported emplacement and non-emplacement drifts was evaluated in this analysis. The excavation effects (i.e., state of the stress change due to excavation), thermal effects (i.e., due to heat output from waste packages), and seismic effects (i.e., from potential earthquake events) were evaluated, and stress controlled modes of failure were examined for two in situ stress conditions (k_0=0.3 and 1.0) using rock properties representing rock mass categories of 1 and 5. Variation of rock mass units such as the non-lithophysal (Tptpmn) and lithophysal (Tptpll) was considered in the analysis. The focus was on the non-lithophysal unit because this unit appears to be relatively weaker and has much smaller joint spacing. Therefore, the drift stability and ground support needs were considered to be controlled by the design for this rock unit. The ground support systems for both emplacement and non-emplacement drifts were incorporated into the models to assess their performance under in situ, thermal, and seismic loading conditions. Both continuum and discontinuum modeling approaches were employed in the analyses of the rock mass behavior and in the evaluation of the

  8. In-Drift Precipitates/Salts Analysis

    SciTech Connect

    P. Mariner

    2001-01-10

    As directed by a written development plan (CRWMS M&O 1999a), an analysis of the effects of salts and precipitates on the repository chemical environment is to be developed and documented in an Analyses/Model Report (AMR). The purpose of this analysis is to assist Performance Assessment Operations (PAO) and the Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift, thus allowing PAO to provide a more detailed and complete in-drift geochemical model abstraction and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near Field Environment (NFE) Revision 2 (NRC 1999). The purpose of this ICN is to qualify and document qualification of the AMR's technical products. The scope of this document is to develop a model of the processes that govern salt precipitation and dissolution and resulting water composition in the Engineered Barrier System (EBS). This model is developed to serve as a basis for the in-drift geochemical modeling work performed by PAO and is to be used in subsequent PAO analyses including the EBS physical and chemical model abstraction effort. However, the concepts may also apply to some near and far field geochemical processes and can have conceptual application within the unsaturated zone and saturated zone transport modeling efforts. The intended use of the model developed in this report is to estimate, within an appropriate level of confidence, the pH, chloride concentration, and ionic strength of water on the drip shield or other location within the drift during the post-closure period. These estimates are based on evaporative processes that are subject to a broad range of potential environmental conditions and are independent of the presence or absence of backfill. An additional intended use is to estimate the environmental conditions required for complete vaporization of water. The presence and composition of liquid water in

  9. Abstraction of Drift-Scale Coupled Processes

    SciTech Connect

    N.D. Francis; D. Sassani

    2000-03-31

    This Analysis/Model Report (AMR) describes an abstraction, for the performance assessment total system model, of the near-field host rock water chemistry and gas-phase composition. It also provides an abstracted process model analysis of potentially important differences in the thermal hydrologic (TH) variables used to describe the performance of a geologic repository obtained from models that include fully coupled reactive transport with thermal hydrology and those that include thermal hydrology alone. Specifically, the motivation of the process-level model comparison between fully coupled thermal-hydrologic-chemical (THC) and thermal-hydrologic-only (TH-only) is to provide the necessary justification as to why the in-drift thermodynamic environment and the near-field host rock percolation flux, the essential TH variables used to describe the performance of a geologic repository, can be obtained using a TH-only model and applied directly into a TSPA abstraction without recourse to a fully coupled reactive transport model. Abstraction as used in the context of this AMR refers to an extraction of essential data or information from the process-level model. The abstraction analysis reproduces and bounds the results of the underlying detailed process-level model. The primary purpose of this AMR is to abstract the results of the fully-coupled, THC model (CRWMS M&O 2000a) for effects on water and gas-phase composition adjacent to the drift wall (in the near-field host rock). It is assumed that drift wall fracture water and gas compositions may enter the emplacement drift before, during, and after the heating period. The heating period includes both the preclosure, in which the repository drifts are ventilated, and the postclosure periods, with backfill and drip shield emplacement at the time of repository closure. Although the preclosure period (50 years) is included in the process models, the postclosure performance assessment starts at the end of this initial period

  10. Airborne organophosphate pesticides drift in Mediterranean climate: The importance of secondary drift

    NASA Astrophysics Data System (ADS)

    Zivan, Ohad; Segal-Rosenheimer, Michal; Dubowski, Yael

    2016-02-01

    Pesticide application is a short-term air-pollution episode with near and far field effects due to atmospheric drift. In order to better evaluate resulting air concentrations in nearby communities following pesticide application, measurements of airborne pesticides were conducted at ∼70 m from field edge. This was done following three different application events of the organophosphate pesticide Chlorpyrifos in a persimmon orchard. Complementary information on larger spatial scale was obtained using CALPUFF modeling in which application and meteorological data was used to better evaluate dispersion patterns. Measurements indicated high airborne concentrations during application hours (few μg m-3 for 8 h average), which dropped to tens of ng m-3 in the following days. Measured atmospheric concentrations show that secondary drift (i.e., post-application drift) involves significant loads of pesticides and hence should not be ignored in exposure considerations. Furthermore, CALPUFF modeling revealed the complex dispersion pattern when weak winds prevailed, and showed that during the 24 h after application air concentrations reached levels above the hourly Texas effect screening level (0.1 μg m-3). Interestingly, weak winds on the night after application resulted in a secondary peak in measured and modeled air concentrations. Long exposure time (when secondary drift is considered) and concentrations measured following such common air-assisted orchard application, suggest pesticide drift may have health repercussions that are currently unknown, and emphasize the need for further epidemiological studies.

  11. Pressurized drift tubes scintillating fiber hadron calorimetry. Final report

    SciTech Connect

    Bromberg, C.; Huston, J.; Miller, R.

    1995-03-22

    Under this contract members of the MSU high energy physics group constructed a full-scale Pressurized Drift Tube Chamber intended for the GEM muon system at the SSC. They achieved a position resolution of <90 {mu} over the full 5 m{sup 2} area of the detector. This resolution satisfied the GEM resolution requirements of <100 {mu} by a comfortable margin. Based on their SSC work they developed a new technique for creating wire supports in drift tubes with an overall placement accuracy of <20 {mu}. This technique requires only simple jigging and can be duplicated and operated at low cost. Also, they participated in the design and testing of a hadron calorimeter prototype for GEM. This work lead the authors to develop a semi-automatic welding machine to fuse together two plastic optical fibers. Copies of this machine are currently in use in the CDF endplug upgrade at Fermilab and additional copies are used widely in calorimeter and fiber-tracker construction.

  12. Linear ion source with closed drift and extended acceleration region

    SciTech Connect

    Park, Dong-Hee; Kim, Ji-Hwan; Ermakov, Yury; Choi, Won-Kook

    2008-02-15

    Ion source with closed drift, which is caused by ExB field, and extended acceleration region is discussed. Though conventional circular-type closed drift ion source has advantages of high efficiency of gas ionization and low ion beam energy, there is a limitation in enlarging the beam size. Linear ion source with horse-track shape with 270 mm ceramic channel width is newly designed and tested. Inert gas (Ar) and reactive gas (O{sub 2}) are discharged. Discharge is ignited with voltage of 90 V. Discharge current is proportional to discharge voltage and increases up to 16.3 A in argon and 15.6 A in oxygen at discharge voltage of 320 V. Extracted ion beam current is also proportional to discharge voltage and is saturated after 280 V for both gases. It is measured up to 0.78 mA/cm{sup 2} in argon beam and 0.73 mA/cm{sup 2} in oxygen beam at a distance of 100 mm from the ion source. Argon ion beam shows better space uniformity than oxygen across the beam extraction region.

  13. A drifting GPS buoy for retrieving effective riverbed bathymetry

    NASA Astrophysics Data System (ADS)

    Hostache, R.; Matgen, P.; Giustarini, L.; Teferle, F. N.; Tailliez, C.; Iffly, J.-F.; Corato, G.

    2015-01-01

    Spatially distributed riverbed bathymetry information are rarely available but mandatory for accurate hydrodynamic modeling. This study aims at evaluating the potential of the Global Navigation Satellite System (GNSS), like for instance Global Positioning System (GPS), for retrieving such data. Drifting buoys equipped with navigation systems such as GPS enable the quasi-continuous measurement of water surface elevation, from virtually any point in the world. The present study investigates the potential of assimilating GNSS-derived water surface elevation measurements into hydraulic models in order to retrieve effective riverbed bathymetry. First tests with a GPS dual-frequency receiver show that the root mean squared error (RMSE) on the elevation measurement equals 30 cm provided that a differential post processing is performed. Next, synthetic observations of a drifting buoy were generated assuming a 30 cm average error of Water Surface Elevation (WSE) measurements. By assimilating the synthetic observation into a 1D-Hydrodynamic model, we show that the riverbed bathymetry can be retrieved with an accuracy of 36 cm. Moreover, the WSEs simulated by the hydrodynamic model using the retrieved bathymetry are in good agreement with the synthetic "truth", exhibiting an RMSE of 27 cm.

  14. Assembly techniques for ultra-low mass drift chambers

    NASA Astrophysics Data System (ADS)

    Assiro, R.; Cascella, M.; Grancagnolo, F.; L'Erario, A.; Miccoli, A.; Rella, S.; Spedicato, M.; Tassielli, G.

    2014-03-01

    We presents a novel technique for the fast assembly of next generation ultra low mass drift chambers offering space point resolution of the order of 100 μm and high tolerance to pile-up. The chamber design has been developed keeping in mind the requirements for the search of rare processes: high resolutions (order of 100-200 KeV/c) for particles momenta in a range (50-100 MeV/c) totally dominated by the multiple scattering contribution (e.g., muon and kaon decay experiment such as MEG at PSI and Mu2e and ORKA at Fermilab). We describe a novel wiring strategy enabling the semiautomatic wiring of a complete layer with a high degree of control over wire tension and position. We also present feed-through-less wire anchoring system. These techniques have been already implemented at INFN-Lecce in the construction of a prototype drift chamber to be soon tested with cosmic rays and particle beams.

  15. Measurements Verifying the Optics of the Electron Drift Instrument

    NASA Astrophysics Data System (ADS)

    Kooi, Vanessa; Kletzing, Craig; Bounds, Scott; Sigsbee, Kristine M.

    2015-04-01

    Magnetic reconnection is the process of breaking and reconnecting of opposing magnetic field lines, and is often associated with tremendous energy transfer. The energy transferred by reconnection directly affects people through its influence on geospace weather and technological systems - such as telecommunication networks, GPS, and power grids. However, the mechanisms that cause magnetic reconnection are not well understood. The Magnetospheric Multi-Scale Mission (MMS) will use four spacecraft in a pyramid formation to make three-dimensional measurements of the structures in magnetic reconnection occurring in the Earth's magnetosphere.The spacecraft will repeatedly sample these regions for a prolonged period of time to gather data in more detail than has been previously possible. MMS is scheduled to be launched in March of 2015. The Electron Drift Instrument (EDI) will be used on MMS to measure the electric fields associated with magnetic reconnection. The EDI is a device used on spacecraft to measure electric fields by emitting an electron beam and measuring the E x B drift of the returning electrons after one gyration. This paper concentrates on measurements of the EDI’s optics system. The testing process includes measuring the optics response to a uni-directional electron beam. These measurements are used to verify the response of the EDI's optics and to allow for the optimization of the desired optics state. The measurements agree well with simulations and we are confident in the performance of the EDI instrument.

  16. [Research on the parameter drift problem of near infrared spectra based corn variety discrimination technology].

    PubMed

    Zhang, Li-Ping; Li, Wei-Jun; Wang, Ping; An, Dong

    2012-10-01

    Aiming to differentiate 13 varieties of corn, present paper proposes an effective approach to solving the parameter drift problem of spectrum instruments. Remarkable drift has been found among the inter-day data when using the identical spectrum instrument to acquire sample data at different times, modeling with the intra-day data, and testing with the rest. The correct recognition rate is reduced to only 7.69% in the condition of severe drift. To tackle this problem, this paper proposes a supervised feature-based inter-day combination modeling approach, at first, the representative sample data acquired at multiple times will be selected to make up the modeling set, and then the PLS+LDA algorithm will be applied to extract the feature of varieties which is independent on instrument parameter drift, and finally BPR will be used to identify the varieties. The experiment results indicate that this approach is effective to rectify the data drift at different times, can bring higher recognition rate, and also shows its stability in practice. PMID:23285887

  17. Differentiation with drift: a spatio-temporal genetic analysis of Galapagos mockingbird populations (Mimus spp.).

    PubMed

    Hoeck, Paquita E A; Bollmer, Jennifer L; Parker, Patricia G; Keller, Lukas F

    2010-04-12

    Small and isolated island populations provide ideal systems to study the effects of limited population size, genetic drift and gene flow on genetic diversity. We assessed genetic diversity within and differentiation among 19 mockingbird populations on 15 Galápagos islands, covering all four endemic species, using 16 microsatellite loci. We tested for signs of drift and gene flow, and used historic specimens to assess genetic change over the last century and to estimate effective population sizes. Within-population genetic diversity and effective population sizes varied substantially among island populations and correlated strongly with island size, suggesting that island size serves as a good predictor for effective population size. Genetic differentiation among populations was pronounced and increased with geographical distance. A century of genetic drift did not change genetic diversity on an archipelago-wide scale, but genetic drift led to loss of genetic diversity in small populations, especially in one of the two remaining populations of the endangered Floreana mockingbird. Unlike in other Galápagos bird species such as the Darwin's finches, gene flow among mockingbird populations was low. The clear pattern of genetically distinct populations reflects the effects of genetic drift and suggests that Galápagos mockingbirds are evolving in relative isolation. PMID:20194174

  18. Geotechnical characterization for the Main Drift of the Exploratory Studies Facility

    SciTech Connect

    Kicker, D.C.; Martin, E.R.; Brechtel, C.E.; Stone, C.A.; Kessel, D.S.

    1997-07-01

    Geotechnical characterization of the Main Drift of the Exploratory Studies Facility was based on borehole data collected in site characterization drilling and on scanline rock mass quality data collected during the excavation of the North Ramp. The Main Drift is the planned 3,131-m near-horizontal tunnel to be excavated at the potential repository horizon for the Yucca Mountain Site Characterization Project. Main Drift borehole data consisted of three holes--USW SD-7, SD-9, and SD-12--drilled along the tunnel alignment. In addition, boreholes USW UZ-14, NRG-6, and NRG-7/7A were used to supplement the database on subsurface rock conditions. Specific data summarized and presented included lithologic and rock structure core logs, rock mechanics laboratory testing, and rock mass quality indices. Cross sections with stratigraphic and thermal-mechanical units were also presented. Topics discussed in the report include geologic setting, geologic features of engineering and construction significance, anticipated ground conditions, and the range of required ground support. Rock structural and rock mass quality data have been developed for each 3-m interval of core in the middle nonlithophysal stratigraphic zone of the Topopah Spring Tuff Formation. The distribution of the rock mass quality data in all boreholes used to characterize the Main Drift was assumed to be representative of the variability of the rock mass conditions to be encountered in the Main Drift. Observations in the North Ramp tunnel have been used to project conditions in the lower lithophysal zone and in fault zones.

  19. Drift-driven evolution of electric signals in a Neotropical knifefish.

    PubMed

    Picq, Sophie; Alda, Fernando; Bermingham, Eldredge; Krahe, Rüdiger

    2016-09-01

    Communication signals are highly diverse traits. This diversity is usually assumed to be shaped by selective forces, whereas the null hypothesis of divergence through drift is often not considered. In Panama, the weakly electric fish Brachyhypopomus occidentalis is widely distributed in multiple independent drainage systems, which provide a natural evolutionary laboratory for the study of genetic and signal divergence in separate populations. We quantified geographic variation in the electric signals of 109 fish from five populations, and compared it to the neutral genetic variation estimated from cytochrome oxidase I (COI) sequences of the same individuals, to test whether drift may be driving divergence of their signals. Signal distances were highly correlated with genetic distances, even after controlling for geographic distances, suggesting that drift alone is sufficient to explain geographic variation in electric signals. Significant differences at smaller geographic scales (within drainages) showed, however, that electric signals may evolve at a faster rate than expected under drift, raising the possibility that additional adaptive forces may be contributing to their evolution. Overall, our data point to stochastic forces as main drivers of signal evolution in this species and extend the role of drift in the evolution of communication systems to fish and electrocommunication. PMID:27436179

  20. Determination of Importance Evaluation for the ESF Enhanced Charcterization of the Repository Block Cross Drift

    SciTech Connect

    S. Goodin

    2002-01-09

    The objective of this DIE is to determine whether the ECRB-Cross-Drift-related activities, as identified in Section 6.0, could potentially impact (1) Yucca Mountain Site Characterization Project (YMP) testing or (2) the waste isolation capabilities of a potential repository at the Yucca Mountain site. Any controls necessary to limit such potential impacts are also identified herein.

  1. Evaluation of the EPA Drift Reduction Technology (DRT) low-speed wind tunnel protocol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The EPA’s proposed Drift Reduction Technology low-speed wind tunnel evaluation protocol was tested across a series of modified ASAE reference nozzles. Both droplet size and deposition and flux volume measurements were made downwind from the nozzles operating in the tunnel at airspeeds of 1 and 2.5 ...

  2. An Examination of Two Procedures for Identifying Consequential Item Parameter Drift

    ERIC Educational Resources Information Center

    Wells, Craig S.; Hambleton, Ronald K.; Kirkpatrick, Robert; Meng, Yu

    2014-01-01

    The purpose of the present study was to develop and evaluate two procedures flagging consequential item parameter drift (IPD) in an operational testing program. The first procedure was based on flagging items that exhibit a meaningful magnitude of IPD using a critical value that was defined to represent barely tolerable IPD. The second procedure…

  3. The Impact of Multidirectional Item Parameter Drift on IRT Scaling Coefficients and Proficiency Estimates

    ERIC Educational Resources Information Center

    Han, Kyung T.; Wells, Craig S.; Sireci, Stephen G.

    2012-01-01

    Item parameter drift (IPD) occurs when item parameter values change from their original value over time. IPD may pose a serious threat to the fairness and validity of test score interpretations, especially when the goal of the assessment is to measure growth or improvement. In this study, we examined the effect of multidirectional IPD (i.e., some…

  4. Negative Ion Drift Velocity and Longitudinal Diffusion in Mixtures of Carbon Disulfide and Methane

    NASA Technical Reports Server (NTRS)

    Dion, Michael P.; Son, S.; Hunter, S. D.; deNolfo, G. A.

    2011-01-01

    Negative ion drift velocity and longitudinal diffusion has been measured for gas mixtures of carbon disulfide (CS2) and methane (CH4)' Measurements were made as a function of total pressure, CS2 partial pressure and electric field. Constant mobility and thermal-limit longitudinal diffusion is observed for all gas mixtures tested. Gas gain for some of the mixtures is also included.

  5. Ionospheric vertical drift response at a mid-latitude station

    NASA Astrophysics Data System (ADS)

    Kouba, Daniel; Koucká Knížová, Petra

    2016-07-01

    Vertical plasma drift data measured at a mid-latitude ionospheric station Pruhonice (50.0 ° N, 14.6 ° E) were collected and analysed for the year 2006, a year of low solar and geomagnetic activity. Hence these data provide insight into the drift behaviour during quiet conditions. The following typical diurnal trend is evident: a significant decay to negative values (downward peak) at dawn; generally less pronounced downward peak at dusk hours. Magnitude of the downward drift varies during the year. Typically it reaches values about 20 ms-1 at dawn hours and 10 ms-1 at dusk hours. Maximum dawn magnitude of about 40 ms-1 has been detected in August. During daytime the vertical drifts increases from the initial small downward drifts to zero drift around noon and to small upward drifts in the afternoon. Night-time drift values display large variability around a near zero vertical drift average. There is a significant trend to larger downward drift values near dawn and a less pronounced decrease of the afternoon upward vertical drifts near sunset. Two regular downward peaks of the drift associated with the dawn and dusk are general characteristics of the analysed data throughout the year 2006. Their seasonal course corresponds to the seasonal course of the sunrise and sunset. The duration of prevailing negative drift velocities forming these peaks and thus the influence of the dawn/dusk on the drift velocity is mostly 1.5-3 h. The dawn effect on vertical drift tends to be larger than the effect of the dusk. The observed magnitude of the sunrise and sunset peaks show significant annual course. The highest variability of the magnitude is seen during winter. High variability is detected till March equinox and again after September equinox. Around solstice, both peaks reaches lowest values. After that, the magnitudes of the drift velocity increase smoothly till maxima in summer (August). The vertical drift velocity course is smooth between June solstice and September

  6. Covariance Matrix Adaptation Evolutionary Strategy for Drift Correction of Electronic Nose Data

    NASA Astrophysics Data System (ADS)

    Di Carlo, S.; Falasconi, M.; Sanchez, E.; Sberveglieri, G.; Scionti, A.; Squillero, G.; Tonda, A.

    2011-09-01

    Electronic Noses (ENs) might represent a simple, fast, high sample throughput and economic alternative to conventional analytical instruments [1]. However, gas sensors drift still limits the EN adoption in real industrial setups due to high recalibration effort and cost [2]. In fact, pattern recognition (PaRC) models built in the training phase become useless after a period of time, in some cases a few weeks. Although algorithms to mitigate the drift date back to the early 90 this is still a challenging issue for the chemical sensor community [3]. Among other approaches, adaptive drift correction methods adjust the PaRC model in parallel with data acquisition without need of periodic calibration. Self-Organizing Maps (SOMs) [4] and Adaptive Resonance Theory (ART) networks [5] have been already tested in the past with fair success. This paper presents and discusses an original methodology based on a Covariance Matrix Adaptation Evolution Strategy (CMA-ES) [6], suited for stochastic optimization of complex problems.

  7. Signal-to-noise ratio for temporal integrated drifting images: a model for perceived image sharpening.

    PubMed

    Power, G J; Sturtz, K E

    2000-12-10

    A formulation of signal-to-noise ratio is constructed that uses temporal integrated images from image sequences. Given a blurred image that drifts horizontally at various speeds and at various linear blurs, we prove that this formulation of the signal-to-noise ratio consistently increases with an increase in speed. This increase is shown to model the trends in the human vision system by which drifting blurred images are perceived with increased sharpness. The existing widely used objective quality techniques fail to model the perceptual increase in sharpness. This new formulation, along with other objective quality measures, is tested on several blurred drifting image sequences. The new formulation reflects the theoretically predicted increase in perceived sharpness. PMID:18354675

  8. Influence of determination of reference position of image on rocket take-off drift

    NASA Astrophysics Data System (ADS)

    Cui, Shuhua; Liu, Jun; Shen, Si; Hu, Shaolin

    2016-01-01

    Mathematical analysis model for influence of reference position deviation on carrier rocket take-off drift has been made to tackle the issue on determination of reference position of reticule for optical tracking and measurement of video image in aerospace test range and the variation in rocket take-off drift due to reference position deviation has been subjected to quantitative analysis based on angular error of tracking and lateral error of measuring point as a result of deviation of reference position of reticule cross. The method serves as technical support to quality analysis of rocket take-off deviation measurement data and improvement in data processing precision for carrier rocket take-off drift.

  9. Field experiment on spray drift: deposition and airborne drift during application to a winter wheat crop.

    PubMed

    Wolters, André; Linnemann, Volker; van de Zande, Jan C; Vereecken, Harry

    2008-11-01

    A field experiment was performed to evaluate various techniques for measuring spray deposition and airborne drift during spray application to a winter wheat crop. The application of a spraying agent containing the fluorescent dye Brilliant Sulfo Flavine by a conventional boom sprayer was done according to good agricultural practice. Deposition was measured by horizontal collectors in various arrangements in and outside the treated area. Airborne spray drift was measured both with a passive and an active air collecting system. Spray deposits on top of the treated canopy ranged between 68 and 71% of the applied dose and showed only small differences for various arrangements of the collectors. Furthermore, only small variations were measured within the various groups of collectors used for these arrangements. Generally, the highest spray deposition outside the treated area was measured close to the sprayed plot and was accompanied by a high variability of values, while a rapid decline of deposits was detected in more remote areas. Estimations of spray deposits with the IMAG Drift Calculator were in accordance with experimental findings only for areas located at a distance of 0.5-4.5 m from the last nozzle, while there was an overestimation of a factor of 4 at a distance of 2.0-3.0 m, thus revealing a high level of uncertainty of the estimation of deposition for short distances. Airborne spray drift measured by passive and active air collecting systems was approximately at the same level, when taking into consideration the collector efficiency of the woven nylon wire used as sampling material for the passive collecting system. The maximum value of total airborne spray drift for both spray applications (0.79% of the applied dose) was determined by the active collecting system. However, the comparatively high variability of measurements at various heights above the soil by active and passive collecting systems revealed need for further studies to elucidate the spatial

  10. Open Access

    ERIC Educational Resources Information Center

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder…

  11. Access Denied

    ERIC Educational Resources Information Center

    Villano, Matt

    2008-01-01

    Building access control (BAC)--a catchall phrase to describe the systems that control access to facilities across campus--has traditionally been handled with remarkably low-tech solutions: (1) manual locks; (2) electronic locks; and (3) ID cards with magnetic strips. Recent improvements have included smart cards and keyless solutions that make use…

  12. YUCCA MOUNTAIN SITE CHARACTERIZATION PROJECT EAST-WEST DRIFT SYSTEM SAFETY ANALYSIS

    SciTech Connect

    NA

    1999-06-08

    The purpose of this analysis is to systematically identify and evaluate hazards related to the design of the Yucca Mountain Project Exploratory Studies Facility (ESF) East-West Cross Drift. This analysis builds upon prior ESF System Safety Analyses and incorporates TS Main Drift scenarios, where applicable, into the East-West Drift scenarios. This System Safety Analysis (SSA) focuses on the personnel safety and health hazards associated with the engineered design of the East-West Drift. The analysis also evaluates other aspects of the East-West Drift, including purchased equipment (e.g., scientific mapping platform) or Systems/Structures/Components (SSCs) and out-of-tolerance conditions. In addition to recommending design mitigation features, the analysis identifies the potential need for procedures, training, or Job Safety Analyses (JSAs). The inclusion of this information in the SSA is intended to assist the organization(s) (e.g., constructor, Safety and Health, design) responsible for these aspects of the East-West Drift in evaluating personnel hazards and augment the information developed by these organizations. The SSA is an integral part of the systems engineering process, whereby safety is considered during planning, design, testing, and construction. A largely qualitative approach is used which incorporates operating experiences and recommendations from vendors, the constructor and the operating contractor. The risk assessment in this analysis characterizes the scenarios associated with East-West Drift SSCs in terms of relative risk and includes recommendations for mitigating all identified hazards. The priority for recommending and implementing mitigation control features is: (1) Incorporate measures to reduce risks and hazards into SSC designs. (2) Add safety features and capabilities to existing designs. (3) Develop procedures and conduct training to increase worker awareness of potential hazards, reduce exposure to hazards, and inform personnel of the

  13. SYSTEMS SAFETY ANALYSIS FOR FIRE EVENTS ASSOCIATED WITH THE ECRB CROSS DRIFT

    SciTech Connect

    R. J. Garrett

    2001-12-12

    The purpose of this analysis is to systematically identify and evaluate fire hazards related to the Yucca Mountain Site Characterization Project (YMP) Enhanced Characterization of the Repository Block (ECRB) East-West Cross Drift (commonly referred to as the ECRB Cross-Drift). This analysis builds upon prior Exploratory Studies Facility (ESF) System Safety Analyses and incorporates Topopah Springs (TS) Main Drift fire scenarios and ECRB Cross-Drift fire scenarios. Accident scenarios involving the fires in the Main Drift and the ECRB Cross-Drift were previously evaluated in ''Topopah Springs Main Drift System Safety Analysis'' (CRWMS M&O 1995) and the ''Yucca Mountain Site Characterization Project East-West Drift System Safety Analysis'' (CRWMS M&O 1998). In addition to listing required mitigation/control features, this analysis identifies the potential need for procedures and training as part of defense-in-depth mitigation/control features. The inclusion of this information in the System Safety Analysis (SSA) is intended to assist the organization(s) (e.g., Construction, Environmental Safety and Health, Design) responsible for these aspects of the ECRB Cross-Drift in developing mitigation/control features for fire events, including Emergency Refuge Station(s). This SSA was prepared, in part, in response to Condition/Issue Identification and Reporting/Resolution System (CIRS) item 1966. The SSA is an integral part of the systems engineering process, whereby safety is considered during planning, design, testing, and construction. A largely qualitative approach is used which incorporates operating experiences and recommendations from vendors, the constructor and the operating contractor. The risk assessment in this analysis characterizes the scenarios associated with fires in terms of relative risk and includes recommendations for mitigating all identified hazards. The priority for recommending and implementing mitigation control features is: (1) Incorporate measures

  14. Notes on radial drift for dalitz detection

    SciTech Connect

    Thomas, J H

    1992-08-21

    One solution to the problem of identifying electron pairs due to dalitz decay is to exploit the large difference in energy lose by electrons and pions at momenta below 150 MEV/C. The restricted'' energy loss is measured by averaging the bottom 60% of the energy loss samples in order to avoid the wide fluctuations caused by the Landau tails. Note that the electrons are fully relativistic and well up on the relativistic rise of the dE/dx curve at a momentum of 30 MeV/c whereas the pions are still moving down off the peak of the Bragg curve and are more heavily ionizing than the electrons. The separation between pions and electrons is very good up to about the pion rest mass and so we can in principle separate the species all through the kinematically allowed range for Dalitz decay but, in practice, the dE/dx resolution will eventually limit the technique to the range well below where the curves crossover. We then might need an additional technique for e/[pi] separation above 110 MeV/c or so. Time of Flight would be a suitable technique. We propose to use a radial drift Time Expansion Chamber (TEC, or sometimes known as at Time Projection Chamber, TPC) to simultaniously measure the energy loss and momentum of electrons and pions. The detector would be placed at Y=0 and extend to [plus minus] 0.5 units of rapidity and the secondary electrons generated by a track would drift radially away from the vertex towards a sensepad plane. The detector would be inside the magnetic field of the RE2 detector and the drift direction would be perpendicular to the field direction.

  15. Daytime plasma drifts in the equatorial lower ionosphere

    NASA Astrophysics Data System (ADS)

    Hui, Debrup; Fejer, Bela G.

    2015-11-01

    We have used extensive radar measurements from the Jicamarca Observatory during low solar flux periods to study the quiet time variability and altitudinal dependence of equatorial daytime vertical and zonal plasma drifts. The daytime vertical drifts are upward and have largest values during September-October. The day-to-day variability of these drifts does not change with height between 150 and 600 km, but the bimonthly variability is much larger in the F region than below about 200 km. These drifts vary linearly with height generally increasing in the morning and decreasing in the afternoon. The zonal drifts are westward during the day and have largest values during July-October. The 150 km region zonal drifts have much larger day-to-day, but much smaller bimonthly variability than the F region drifts. The daytime zonal drifts strongly increase with height up to about 300 km from March through October, and more weakly at higher altitudes. The December solstice zonal drifts have generally weaker altitudinal dependence, except perhaps below 200 km. Current theoretical and general circulation models do not reproduce the observed altitudinal variation of the daytime equatorial zonal drifts.

  16. MAGSAT anomaly map and continental drift

    NASA Technical Reports Server (NTRS)

    Lemouel, J. L. (Principal Investigator); Galdeano, A.; Ducruix, J.

    1981-01-01

    Anomaly maps of high quality are needed to display unambiguously the so called long wave length anomalies. The anomalies were analyzed in terms of continental drift and the nature of their sources is discussed. The map presented confirms the thinness of the oceanic magnetized layer. Continental magnetic anomalies are characterized by elongated structures generally of east-west trend. Paleomagnetic reconstruction shows that the anomalies found in India, Australia, and Antarctic exhibit a fair consistency with the African anomalies. It is also shown that anomalies are locked under the continents and have a fixed geometry.

  17. Experimental study of low frequency drift instability

    SciTech Connect

    Ioffe, M.S.; Kanaev, B.I.; Pastukhov, V.P.

    1994-05-01

    Experimental studies of nondissipative low frequency drift instability are reported; the plasma of a long mirror trap with edge casp anchors was investigated. The instability growth was found to take place only in a limited number of operation modes even in the case of all the growth requirements being satisfied. Furthermore, the instability development is rather moderate, and the associated anomalous losses appear to be small compared to the classical Coulomb losses. Possible factors accounting for the {open_quotes}soft{close_quotes} instability evolution are discussed. 13 refs., 6 figs.

  18. A drift model of interchange instability

    SciTech Connect

    Benilov, E. S.; Power, O. A.

    2007-08-15

    A set of asymptotic equations is derived, describing the dynamics of the flute mode in a magnetized plasma with cold ions, under a 'local' approximation (i.e., near a particular point). The asymptotic set is then used to calculate the growth rate of interchange instability in the slab model. It is shown that, unlike the magnetohydrodynamic ordering, the drift one allows instability to occur for either sign of the pressure gradient (i.e., for both 'bad' and 'good' curvature of the magnetic field). It is also demonstrated that finite beta gives rise to an extra instability that does not exist in the small-beta limit.

  19. Effects of grids in drift tubes

    SciTech Connect

    Okamura M.; Yamauchi, H.

    2012-05-20

    In 2011, we upgraded a 201 MHz buncher in the proton injector for the alternating gradient synchrotron (AGS) - relativistic heavy ion collider (RHIC) complex. In the buncher we installed four grids made of tungsten to improve the transit time factor. The grid installed drift tubes have 32 mm of inner diameter and the each grid consists of four quadrants. The quadrants were cut out precisely from 1mm thick tungsten plates by a computerized numerically controlled (CNC) wire cutting electrical discharge machining (EDM). The 3D electric field of the grid was simulated.

  20. Ergodic mixing for turbulent drift motion

    SciTech Connect

    Isichenko, M.B.; Petviashvili, N.V.

    1995-02-16

    The statistical properties of the long-time chaotic two-dimensional (2D) drift motion of a charged particle in an inhomogeneous magnetic field {beta}(x,y) and a time-dependent electrostatic potential {phi}(x,y,t) are studied by numerical symplectic integration. For a conditionally periodic potential with two or more incommensurate frequencies, an ergodic behavior is demonstrated in which the probability density of the particle position is proportional to the magnetic field {beta}. The accuracy of this prediction is found to be independent of the number N{sub {omega}} of the incommensurate frequencies for N{sub {omega}} {ge}2.

  1. Results from the DRIFT Dark Matter Search

    NASA Astrophysics Data System (ADS)

    Ayad, R.; Hyatt, M.; Hanson-Hart, Z.; Katz-Hyman, M.; Martoff, C. J.; Kirkpatrick, J.; Snowden-Ifft, D. P.; Lawson, T. B.; Lightfoot, P. K.; Morgan, B.; Paling, S. M.; Robinson, M.; Spooner, N. J. C.

    2004-05-01

    DRIFT [1] is the only direction-sensitive WIMP Dark Matter search experiment now running underground. It employs a novel detector invented for this purpose: the Negative Ion TPC (NITPC). Data is collected in the form of digitized time-records of signals received on each active anode wire of the NITPC endcap. New Results from 2002 data taking will be presented, especially on underground neutron calibration and background. [1] Low Pressure Negative Ion TPC for Dark Matter Search. D. P.Snowden-Ifft, C. J. Martoff, J. M. Burwell, Phys Rev. D. Rapid Comm. 61,101301 (2000).

  2. Drift Chamber Alignment using Cosmic Rays

    SciTech Connect

    Kotwal, Ashutosh V.; Hays, Christopher P.

    2014-05-07

    The Collider Detector at Fermilab (CDF) is a general-purpose experimental apparatus with an inner tracking detector for measuring charged particles, surrounded by a calorimeter for measurements of electromagnetic and hadronic showers, and a muon detector system. We present a technique for, and results of, a precise relative alignment of the drift chamber wires of the CDF tracker. This alignment has been an important component of the track momentum calibration, which is the basis for the charged-lepton calibration for the measurement of the W boson mass at CDF.

  3. Demersally drifting invertebrates from Kongsfjorden, Svalbård (Arctic Ocean)-a comparison of catches from drift-pump and drift-nets

    NASA Astrophysics Data System (ADS)

    Dahms, Hans-Uwe; Joo, Hyoung-Min; Lee, Jae Hyung; Yun, Mi Sun; Ahn, So Hyun; Lee, Sang Heon

    2015-12-01

    Demersally drifting organisms were collected at Ny Ålesund (Svalbård-Arctic Ocean) to study the taxon composition and relative abundances in the Arctic summer. Catch potentials of two collection devices for demersal drift were compared. A lowvolume submersible drift-pump and a drift-net unit were employed for the collection of demersally drifting biota, particularly for shallow aquatic habitats. With the exception of Appendicularia, Chaetognatha, Coelenterata, and Ctenophora, which were damaged at times, the pump catches were in good condition and sufficient for identification and quantification of less mobile fauna. A comparison of the two devices revealed that the drift-pump collected more specimens than the drift-net. However, the drift-net may have caused an underestimation of the abundances of invertebrates. No differences in identified taxon number and indices of richness, evenness and diversity were found. However, the proportion of invertebrate animals in the two devices was different for the three groups: zooplankton, macrofauna and meiofauna. At Svalbård, zooplankton, larvae of macrofauna, and meiofauna were successfully collected by the two collecting devices. However, the catchibility of the two devices in collecting various invertebrate taxa was different and, therefore, a sound `Device Effect' was revealed.

  4. Effective drifts in dynamical systems with multiplicative noise: a review of recent progress.

    PubMed

    Volpe, Giovanni; Wehr, Jan

    2016-05-01

    Noisy dynamical models are employed to describe a wide range of phenomena. Since exact modeling of these phenomena requires access to their microscopic dynamics, whose time scales are typically much shorter than the observable time scales, there is often need to resort to effective mathematical models such as stochastic differential equations (SDEs). In particular, here we consider effective SDEs describing the behavior of systems in the limits when natural time scales become very small. In the presence of multiplicative noise (i.e. noise whose intensity depends upon the system's state), an additional drift term, called noise-induced drift or effective drift, appears. The nature of this noise-induced drift has been recently the subject of a growing number of theoretical and experimental studies. Here, we provide an extensive review of the state of the art in this field. After an introduction, we discuss a minimal model of how multiplicative noise affects the evolution of a system. Next, we consider several case studies with a focus on recent experiments: the Brownian motion of a microscopic particle in thermal equilibrium with a heat bath in the presence of a diffusion gradient; the limiting behavior of a system driven by a colored noise modulated by a multiplicative feedback; and the behavior of an autonomous agent subject to sensorial delay in a noisy environment. This allows us to present the experimental results, as well as mathematical methods and numerical techniques, that can be employed to study a wide range of systems. At the end we give an application-oriented overview of future projects involving noise-induced drifts, including both theory and experiment. PMID:27088308

  5. Effective drifts in dynamical systems with multiplicative noise: a review of recent progress

    NASA Astrophysics Data System (ADS)

    Volpe, Giovanni; Wehr, Jan

    2016-05-01

    Noisy dynamical models are employed to describe a wide range of phenomena. Since exact modeling of these phenomena requires access to their microscopic dynamics, whose time scales are typically much shorter than the observable time scales, there is often need to resort to effective mathematical models such as stochastic differential equations (SDEs). In particular, here we consider effective SDEs describing the behavior of systems in the limits when natural time scales become very small. In the presence of multiplicative noise (i.e. noise whose intensity depends upon the system’s state), an additional drift term, called noise-induced drift or effective drift, appears. The nature of this noise-induced drift has been recently the subject of a growing number of theoretical and experimental studies. Here, we provide an extensive review of the state of the art in this field. After an introduction, we discuss a minimal model of how multiplicative noise affects the evolution of a system. Next, we consider several case studies with a focus on recent experiments: the Brownian motion of a microscopic particle in thermal equilibrium with a heat bath in the presence of a diffusion gradient; the limiting behavior of a system driven by a colored noise modulated by a multiplicative feedback; and the behavior of an autonomous agent subject to sensorial delay in a noisy environment. This allows us to present the experimental results, as well as mathematical methods and numerical techniques, that can be employed to study a wide range of systems. At the end we give an application-oriented overview of future projects involving noise-induced drifts, including both theory and experiment.

  6. Risk of Active Tuberculosis in HIV-Infected Patients in Taiwan with Free Access to HIV Care and a Positive T-Spot.TB Test

    PubMed Central

    Sun, Hsin-Yun; Hsueh, Po-Ren; Liu, Wen-Chun; Su, Yi-Ching; Chang, Sui-Yuan; Hung, Chien-Ching; Chang, Shan-Chwen

    2015-01-01

    Background Interferon-gamma release assays (IGRAs) have been used to identify individuals at risk for developing active tuberculosis (TB). However, data regarding the risk of TB development in HIV-infected patients testing positive for IGRAs remain sparse in the era of combination antiretroviral therapy. Methods Between 2011 and 2013, 608 HIV-infected patients without active TB undergoing T-Spot.TB testing were enrolled in this prospective observational study at a university hospital designated for HIV care in Taiwan with a declining TB incidence from 72 per 100,000 population in 2005 to 53 per 100,000 population in 2012. All of the subjects were followed until September 30, 2014. The national TB registry was accessed to identify any TB cases among those lost to follow-up. Results T-Spot.TB tested negative in 534 patients (87.8%), positive in 64 patients (10.5%), and indeterminate in 10 patients (1.6%). In multivariate analysis, positive T-Spot.TB was significantly associated with older age (adjusted odds ratio [AOR], 1.172 per 10-year increase; 95% confidence interval [CI], 1.022-1.344, P=0.023), past history of TB (AOR, 13.412; 95% CI, 6.106-29.460, P<0.001), and higher CD4 counts at enrollment (AOR, per 50-cell/μl increase, 1.062; 95% CI, 1.017-1.109, P=0.007). Of the 64 patients testing positive for T-Spot.TB, none received isoniazid preventive therapy and all but 5 received combination antiretroviral therapy at the end of follow-up with the latest CD4 count and plasma HIV RNA load being 592.8 cells/μL and 1.85 log10 copies/mL, respectively. One patient (1.6%) developed active TB after 167 person-years of follow-up (PYFU), resulting in an incidence rate of 0.599 per 100 PFYU. None of the 534 patients testing negative for T-Spot.TB developed TB after 1380 PYFU, nor did the 24 patients with old TB and positive T-Spot.TB tests develop TB after 62.33 PYFU. Conclusions The risk of developing active TB in HIV-infected patients with positive T-Spot.TB receiving

  7. Fabrication of vertex drift chamber with 1.75mm drift length

    NASA Astrophysics Data System (ADS)

    Sakuma, F.; En'yo, H.; Tabaru, T.; Yokkaichi, S.; Ishino, M.; Mihara, S.; Ozawa, K.; Hamagaki, H.; Funahashi, H.; Kitaguchi, M.; Miyashita, T.; Murakami, T.; Muto, R.; Naruki, M.; Sato, H. D.; Yamada, S.; Yoshimura, Y.; Kanda, H.; Chiba, J.; Ieiri, M.; Sasaki, O.; Sekimoto, M.; Tanaka, K. H.; Nomachi, M.

    2001-10-01

    The fabrication and the performance of the vertex drift chamber for the KEK-PS E325 are presented. The chamber consists of 3 layers of hexagonal drift cells with sides 3.02mm or 2.02mm long, depending on the region of polar angle coverage. The smallest drift length is only 1.75mm long. Such a geometry is realized with normal feed-through technics on the alminum frame by grounding cathodes and applying high voltages on anodes. The drift cells surround the targets at radii of 100 mm and 200 mm covering the polar angle region of 6 degrees to 141 degrees. The chamber is operated under 10^9/sec primary beam intensity, and the minimum distance between the beam and the sense wires is only 21mm. The chamber uses Amplifier-Shaper-Discriminator ICs (SONY CXA3183Q) for read-out, which are developed for Thin Gap Chamber for the ATLAS mun detector. In the presentation, we will report details of the chamber design and the measured performance.

  8. Maternal high-fat diet during pregnancy and lactation reduces the appetitive behavioral component in female offspring tested in a brief-access taste procedure.

    PubMed

    Treesukosol, Yada; Sun, Bo; Moghadam, Alexander A; Liang, Nu-Chu; Tamashiro, Kellie L; Moran, Timothy H

    2014-04-01

    Maternal high-fat diet appears to disrupt several energy balance mechanisms in offspring. Here, female offspring from dams fed a high-fat diet (HF) did not significantly differ in body weight compared with those fed chow (CHOW), when weaned onto chow diet. Yet when presented with both a chow and a high-fat diet, high-fat intake was significantly higher in HF compared with CHOW offspring. To assess taste-based responsiveness, offspring (12 wk old) were tested in 30-min sessions (10-s trials) to a sucrose concentration series in a brief-access taste test. Compared with CHOW, the HF offspring initiated significantly fewer trials but did not significantly differ in the amount of concentration-dependent licking. Thus, rather than affect lick response (consummatory), maternal diet affects spout approach (appetitive), which may be attributed to motivation-related mechanisms. Consistent with this possibility, naltrexone, an opioid receptor antagonist, further reduced trial initiation, but not licking in both groups. With naltrexone administration, the group difference in trial initiation was no longer evident, suggesting differences in endogenous opioid activity between the two groups. Relative expression of μ-opioid receptor in the ventral tegmental area was significantly lower in HF rats. When trial initiation was not required in one-bottle intake tests, no main effect of maternal diet on the intake of sucrose and corn oil emulsions was observed. Thus, the maternal high-fat diet-induced difference in diet preference is not likely due to changes in the sensory orosensory component of the taste stimulus but may depend on alterations in satiety signals or absorptive mechanisms. PMID:24500433

  9. Maternal high-fat diet during pregnancy and lactation reduces the appetitive behavioral component in female offspring tested in a brief-access taste procedure

    PubMed Central

    Sun, Bo; Moghadam, Alexander A.; Liang, Nu-Chu; Tamashiro, Kellie L.; Moran, Timothy H.

    2014-01-01

    Maternal high-fat diet appears to disrupt several energy balance mechanisms in offspring. Here, female offspring from dams fed a high-fat diet (HF) did not significantly differ in body weight compared with those fed chow (CHOW), when weaned onto chow diet. Yet when presented with both a chow and a high-fat diet, high-fat intake was significantly higher in HF compared with CHOW offspring. To assess taste-based responsiveness, offspring (12 wk old) were tested in 30-min sessions (10-s trials) to a sucrose concentration series in a brief-access taste test. Compared with CHOW, the HF offspring initiated significantly fewer trials but did not significantly differ in the amount of concentration-dependent licking. Thus, rather than affect lick response (consummatory), maternal diet affects spout approach (appetitive), which may be attributed to motivation-related mechanisms. Consistent with this possibility, naltrexone, an opioid receptor antagonist, further reduced trial initiation, but not licking in both groups. With naltrexone administration, the group difference in trial initiation was no longer evident, suggesting differences in endogenous opioid activity between the two groups. Relative expression of μ-opioid receptor in the ventral tegmental area was significantly lower in HF rats. When trial initiation was not required in one-bottle intake tests, no main effect of maternal diet on the intake of sucrose and corn oil emulsions was observed. Thus, the maternal high-fat diet-induced difference in diet preference is not likely due to changes in the sensory orosensory component of the taste stimulus but may depend on alterations in satiety signals or absorptive mechanisms. PMID:24500433

  10. Metabolic drift in the aging brain.

    PubMed

    Ivanisevic, Julijana; Stauch, Kelly L; Petrascheck, Michael; Benton, H Paul; Epstein, Adrian A; Fang, Mingliang; Gorantla, Santhi; Tran, Minerva; Hoang, Linh; Kurczy, Michael E; Boska, Michael D; Gendelman, Howard E; Fox, Howard S; Siuzdak, Gary

    2016-05-01

    Brain function is highly dependent upon controlled energy metabolism whose loss heralds cognitive impairments. This is particularly notable in the aged individuals and in age-related neurodegenerative diseases. However, how metabolic homeostasis is disrupted in the aging brain is still poorly understood. Here we performed global, metabolomic and proteomic analyses across different anatomical regions of mouse brain at different stages of its adult lifespan. Interestingly, while severe proteomic imbalance was absent, global-untargeted metabolomics revealed an energymetabolic drift or significant imbalance in core metabolite levels in aged mouse brains. Metabolic imbalance was characterized by compromised cellular energy status (NAD decline, increased AMP/ATP, purine/pyrimidine accumulation) and significantly altered oxidative phosphorylation and nucleotide biosynthesis and degradation. The central energy metabolic drift suggests a failure of the cellular machinery to restore metabostasis (metabolite homeostasis) in the aged brain and therefore an inability to respond properly to external stimuli, likely driving the alterations in signaling activity and thus in neuronal function and communication. PMID:27182841

  11. EMPLACEMENT DRIFT ISOLATION DOOR CONTROL SYSTEM

    SciTech Connect

    N.T. Raczka

    1998-09-17

    The purpose of this analysis is to review and refine key design concepts related to the control system presently under consideration for remotely operating the emplacement drift isolation doors at the potential subsurface nuclear waste repository at Yucca Mountain. This analysis will discuss the key design concepts of the control system that may be utilized for remotely monitoring, opening, and closing the emplacement drift isolation doors. The scope and primary objectives of this analysis are to: (1) Discuss the purpose and function of the isolation doors (Presented in Section 7.1). (2) Review the construction of the isolation door and other physical characteristics of the doors that the control system will interface with (Presented in Section 7.2). (3) Discuss monitoring and controlling the operation of the isolation doors with a digital control system (either a Programmable Logic Controller (PLC) system or a Distributed Control System (DCS)) (Presented in Section 7.3). (4) Discuss how all isolation doors can be monitored and controlled from a subsurface central control center (Presented in Section 7.4). This analysis will focus on the development of input/output (I/O) counts including the types of I/O, redundancy and fault tolerance considerations, and processor requirements for the isolation door control system. Attention will be placed on operability, maintainability, and reliability issues for the system operating in the subsurface environment with exposure to high temperatures and radiation.

  12. Snow particle speeds in drifting snow

    NASA Astrophysics Data System (ADS)

    Nishimura, Kouichi; Yokoyama, Chika; Ito, Yoichi; Nemoto, Masaki; Naaim-Bouvet, Florence; Bellot, Hervé; Fujita, Koji

    2014-08-01

    Knowledge of snow particle speeds is necessary for deepening our understanding of the internal structures of drifting snow. In this study, we utilized a snow particle counter (SPC) developed to observe snow particle size distributions and snow mass flux. Using high-frequency signals from the SPC transducer, we obtained the sizes of individual particles and their durations in the sampling area. Measurements were first conducted in the field, with more precise measurements being obtained in a boundary layer established in a cold wind tunnel. The obtained results were compared with the results of a numerical analysis. Data on snow particle speeds, vertical velocity profiles, and their dependence on wind speed obtained in the field and in the wind tunnel experiments were in good agreement: both snow particle speed and wind speed increased with height, and the former was always 1 to 2 m s-1 less than the latter below a height of 1 m. Thus, we succeeded in obtaining snow particle speeds in drifting snow, as well as revealing the dependence of particle speed on both grain size and wind speed. The results were verified by similar trends observed using random flight simulations. However, the difference between the particle speed and the wind speed in the simulations was much greater than that observed under real conditions. Snow transport by wind is an aeolian process. Thus, the findings presented here should be also applicable to other geophysical processes relating to the aeolian transport of particles, such as blown sand and soil.

  13. Species selection and random drift in macroevolution.

    PubMed

    Chevin, Luis-Miguel

    2016-03-01

    Species selection resulting from trait-dependent speciation and extinction is increasingly recognized as an important mechanism of phenotypic macroevolution. However, the recent bloom in statistical methods quantifying this process faces a scarcity of dynamical theory for their interpretation, notably regarding the relative contributions of deterministic versus stochastic evolutionary forces. I use simple diffusion approximations of birth-death processes to investigate how the expected and random components of macroevolutionary change depend on phenotype-dependent speciation and extinction rates, as can be estimated empirically. I show that the species selection coefficient for a binary trait, and selection differential for a quantitative trait, depend not only on differences in net diversification rates (speciation minus extinction), but also on differences in species turnover rates (speciation plus extinction), especially in small clades. The randomness in speciation and extinction events also produces a species-level equivalent to random genetic drift, which is stronger for higher turnover rates. I then show how microevolutionary processes including mutation, organismic selection, and random genetic drift cause state transitions at the species level, allowing comparison of evolutionary forces across levels. A key parameter that would be needed to apply this theory is the distribution and rate of origination of new optimum phenotypes along a phylogeny. PMID:26880617

  14. Metabolic drift in the aging brain

    PubMed Central

    Ivanisevic, Julijana; Stauch, Kelly L.; Petrascheck, Michael; Benton, H. Paul; Epstein, Adrian A.; Fang, Mingliang; Gorantla, Santhi; Tran, Minerva; Hoang, Linh; Kurczy, Michael E.; Boska, Michael D.; Gendelman, Howard E.; Fox, Howard S.; Siuzdak, Gary

    2016-01-01

    Brain function is highly dependent upon controlled energy metabolism whose loss heralds cognitive impairments. This is particularly notable in the aged individuals and in age-related neurodegenerative diseases. However, how metabolic homeostasis is disrupted in the aging brain is still poorly understood. Here we performed global, metabolomic and proteomic analyses across different anatomical regions of mouse brain at different stages of its adult lifespan. Interestingly, while severe proteomic imbalance was absent, global-untargeted metabolomics revealed an energy metabolic drift or significant imbalance in core metabolite levels in aged mouse brains. Metabolic imbalance was characterized by compromised cellular energy status (NAD decline, increased AMP/ATP, purine/pyrimidine accumulation) and significantly altered oxidative phosphorylation and nucleotide biosynthesis and degradation. The central energy metabolic drift suggests a failure of the cellular machinery to restore metabostasis (metabolite homeostasis) in the aged brain and therefore an inability to respond properly to external stimuli, likely driving the alterations in signaling activity and thus in neuronal function and communication. PMID:27182841

  15. Double-peak subauroral ion drifts (DSAIDs)

    NASA Astrophysics Data System (ADS)

    He, Fei; Zhang, Xiao-Xin; Wang, Wenbin; Chen, Bo

    2016-06-01

    This paper reports double-peak subauroral ion drifts (DSAIDs), which is unique subset of subauroral ion drifts (SAIDs). A statistical analysis has been carried out for the first time with a database of 454 DSAID events identified from Defense Meteorological Satellite Program observations from 1987 to 2012. Both case studies and statistical analyses show that the two velocity peaks of DSAIDs are associated with two ion temperature peaks and two region-2 field-aligned currents (R2-FACs) peaks in the midlatitude ionospheric trough located in the low-conductance subauroral region. DSAIDs are regional and vary significantly with magnetic local time. DSAIDs can evolve from/to SAIDs during their lifetimes, which are from several minutes to tens of minutes. Comparisons between the ionospheric parameters of DSAIDs and SAIDs indicate that double-layer region-2 field-aligned currents (R2-FACs) may be the main driver of DSAIDs. It is also found that DSAIDs happen during more disturbed conditions compared with SAIDs.

  16. Electromagnetic drift waves dispersion for arbitrarily collisional plasmas

    SciTech Connect

    Lee, Wonjae Krasheninnikov, Sergei I.; Angus, J. R.

    2015-07-15

    The impacts of the electromagnetic effects on resistive and collisionless drift waves are studied. A local linear analysis on an electromagnetic drift-kinetic equation with Bhatnagar-Gross-Krook-like collision operator demonstrates that the model is valid for describing linear growth rates of drift wave instabilities in a wide range of plasma parameters showing convergence to reference models for limiting cases. The wave-particle interactions drive collisionless drift-Alfvén wave instability in low collisionality and high beta plasma regime. The Landau resonance effects not only excite collisionless drift wave modes but also suppress high frequency electron inertia modes observed from an electromagnetic fluid model in collisionless and low beta regime. Considering ion temperature effects, it is found that the impact of finite Larmor radius effects significantly reduces the growth rate of the drift-Alfvén wave instability with synergistic effects of high beta stabilization and Landau resonance.

  17. Drift parameters optimization of a TPC polarimeter: a simulation study

    NASA Astrophysics Data System (ADS)

    Rakhee, K.; Radhakrishna, V.; Koushal, V.; Baishali, G.; Vinodkumar, A. M.

    2015-06-01

    Time Projection Chamber (TPC) based X-ray polarimeters using Gas Electron Multiplier (GEM) are currently being developed to make sensitive measurement of polarization in 2-10 keV energy range. The emission direction of the photoelectron ejected via photoelectric effect carries the information of the polarization of the incident X-ray photon. Performance of a gas based polarimeter is affected by the operating drift parameters such as gas pressure, drift field and drift-gap. We present simulation studies carried out in order to understand the effect of these operating parameters on the modulation factor of a TPC polarimeter. Models of Garfield are used to study photoelectron interaction in gas and drift of electron cloud towards GEM. Our study is aimed at achieving higher modulation factors by optimizing drift parameters. Study has shown that Ne/DME (50/50) at lower pressure and drift field can lead to desired performance of a TPC polarimeter.

  18. Conditional capture probability for Scaphirhynchus spp. in drifting trammel nets

    SciTech Connect

    Guy, Christopher S.; Oldenburg, Eric W.; Gerrity, Paul C.

    2009-06-01

    Pallid sturgeon Scaphirhynchus albus and shovelnose sturgeon Scaphirhynchus platorynchus are commonly sampled using drifting-trammel nets in the Missouri River basin. Despite that drifting trammel nets have been used for decades to sample these species, little is known about the capture efficiency of this gear. We estimated conditional capture probability and gear efficiency for drifting trammel nets. In addition we examined several abiotic variables that were assumed to influence the success of capturing a pallid sturgeon or shovelnose sturgeon in a drifting trammel net. Conditional capture probability varied from 0.36 on the first attempt to 0.50 on the second attempt. Drifting trammel nets are relatively efficient and we suggest that they continue to be used to sample in large turbid rivers. The high variability associated with sampling pallid sturgeon and shovelnose sturgeon using drifting trammel nets is likely related to low abundance and patchy distributions. Thus, we suggest using more appropriate sampling designs for rare species.

  19. In-Drift Precipitates/Salts Model

    SciTech Connect

    P. Mariner

    2004-11-09

    This report documents the development and validation of the in-drift precipitates/salts (IDPS) model. The IDPS model is a geochemical model designed to predict the postclosure effects of evaporation and deliquescence on the chemical composition of water within the Engineered Barrier System (EBS) in support of the Total System Performance Assessment for the License Application (TSPA-LA). Application of the model in support of TSPA-LA is documented in ''Engineered Barrier System: Physical and Chemical Environment Model'' (BSC 2004 [DIRS 169860]). Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration (BSC 2004 [DIRS 171156]) is the technical work plan (TWP) for this report. It called for a revision of the previous version of the report (BSC 2004 [DIRS 167734]) to achieve greater transparency, readability, data traceability, and report integration. The intended use of the IDPS model is to estimate and tabulate, within an appropriate level of confidence, the effects of evaporation, deliquescence, and potential environmental conditions on the pH, ionic strength, and chemical compositions of water and minerals on the drip shield or other location within the drift during the postclosure period. Specifically, the intended use is as follows: (1) To estimate, within an appropriate level of confidence, the effects of evaporation and deliquescence on the presence and composition of water occurring within the repository during the postclosure period (i.e., effects on pH, ionic strength, deliquescence relative humidity, total concentrations of dissolved components in the system Na-K-H-Mg-Ca-Al-Cl-F-NO{sub 3}-SO{sub 4}-Br-CO{sub 3}-SiO{sub 2}-CO{sub 2}-O{sub 2}-H{sub 2}O, and concentrations of the following aqueous species that potentially affect acid neutralizing capacity: HCO{sub 3}{sup -}, CO{sub 3}{sup 2-}, OH{sup -}, H{sup +}, HSO{sub 4}{sup -}, Ca{sup 2+}, Mg{sup 2+}, CaHCO{sub 3}{sup +}, MgHCO{sub 3}{sup +}, HSiO{sub 3

  20. The Ion Drift Meter for Dynamics Explorer-B

    NASA Technical Reports Server (NTRS)

    Heelis, R. A.; Hanson, W. B.; Lippincott, C. R.; Zuccaro, D. R.; Harmon, L. H.; Holt, B. J.; Doherty, J. E.; Power, R. A.

    1981-01-01

    The Ion Drift Meter on Dynamics Explorer-B measures two mutually perpendicular angles of arrival of thermal ions with respect to the sensor look direction. These measurements are used to derive two components of the ambient thermal ion drift velocity, which together with the third component from the Retarding Potential Analyzer instrument provide the total velocity. The Ion Drift Meter technique yields high temporal resolution measurements essential in the studies of the convection pattern and energy deposition in the ionosphere.

  1. Analysis of drift correction in different simulated weighing schemes

    NASA Astrophysics Data System (ADS)

    Beatrici, A.; Rebelo, A.; Quintão, D.; Cacais, F. L.; Loayza, V. M.

    2015-10-01

    In the calibration of high accuracy mass standards some weighing schemes are used to reduce or eliminate the zero drift effects in mass comparators. There are different sources for the drift and different methods for its treatment. By using numerical methods, drift functions were simulated and a random term was included in each function. The comparison between the results obtained from ABABAB and ABBA weighing series was carried out. The results show a better efficacy of ABABAB method for drift with smooth variation and small randomness.

  2. Drifts of auroral structures and magnetospheric electric fields

    SciTech Connect

    Nakamura, Rumi; Oguti, Takasi )

    1987-10-01

    Drifts of pulsating auroral patches and discrete auroral arc fragments are analyzed on the basis of all-sky TV observations of auroras. The drifts of auroral structures in this study correspond on a gross scale with other measurements of magnetospheric convection. The result strongly suggests that not only auroral patches but also arc fragments, when detached from the main body of the discrete aurora, drift owing to the magnetospheric electric fields. The measurement of the drifts of auroral structures could possibly provide us with a convenient and accurate method to estimate the magnetospheric electric fields.

  3. Structural Drift: The Population Dynamics of Sequential Learning

    PubMed Central

    Crutchfield, James P.; Whalen, Sean

    2012-01-01

    We introduce a theory of sequential causal inference in which learners in a chain estimate a structural model from their upstream “teacher” and then pass samples from the model to their downstream “student”. It extends the population dynamics of genetic drift, recasting Kimura's selectively neutral theory as a special case of a generalized drift process using structured populations with memory. We examine the diffusion and fixation properties of several drift processes and propose applications to learning, inference, and evolution. We also demonstrate how the organization of drift process space controls fidelity, facilitates innovations, and leads to information loss in sequential learning with and without memory. PMID:22685387

  4. Spin drift in highly doped n-type Si

    SciTech Connect

    Kameno, Makoto; Ando, Yuichiro; Shinjo, Teruya; Koike, Hayato; Sasaki, Tomoyuki; Oikawa, Tohru; Suzuki, Toshio; Shiraishi, Masashi

    2014-03-03

    A quantitative estimation of spin drift velocity in highly doped n-type silicon (Si) at 8 K is presented in this letter. A local two-terminal Hanle measurement enables the detection of a modulation of spin signals from the Si as a function of an external electric field, and this modulation is analyzed by using a spin drift-diffusion equation and an analytical solution of the Hanle-type spin precession. The analyses reveal that the spin drift velocity is linearly proportional to the electric field. The contribution of the spin drift effect to the spin signals is crosschecked by introducing a modified nonlocal four-terminal method.

  5. Analysis and suppression of drain current drift in graphene FETs

    NASA Astrophysics Data System (ADS)

    Park, Jun-Mo; Lee, Dongho; Shim, Jeoyoung; Jeon, Taehan; Eom, Kunsun; Park, Byung-Gook; Lee, Jong-Ho

    2015-10-01

    The cause of drain current (ID) drift in graphene field-effect transistors is analyzed and a method to suppress the drift is proposed. By analyzing ID-time characteristics, a condition of reasonable gate, drain and source biases (VG, VD, and VS) is proposed to suppress ID drift. Based on this result, we find a condition for VG during off-time (Vbase), VD, and VS in pulsed I-V measurement to obtain the intrinsic ID-VG curves, and analyze the effect of Vbase on the Dirac point shift. Through an analysis of ID-time characteristics depending on VG, ID drift according to the range of VG is explained.

  6. A minority research and education information service: Design, develop, pilot test, and implement on-line access for historically black colleges and universities and government agencies

    SciTech Connect

    Rodman, J.A.

    1992-01-01

    This Annual Status Report describes the design, development and implementation of the Minority On-Line Information Service (MOLIS) project by Federal Information Exchange, Inc. for the period of April 1, 1991 to March 31, 1992. Summary information detailing developments prior to this reporting period will also be included to establish a comprehensive perspective of the project. The goal of the MOLIS project, was to develop, design, pilot test on-line access to current information on minority colleges and universities and federal minority opportunities. Federal Information Exchange, Inc. (FIE), a diversified information services company recognized by researchers and educators as a leader in the field of information delivery services, was awarded a 5 year small business research grant to develop and implement MOLIS. Since April 29, 1991, the inauguration of its on-line service, MOLIS has provided current information on 138 Black and Hispanic colleges and universities -- including faculty and student profiles, financial data, research centers and equipment information, pre-college and education programs, emerging capabilities, enrollment data, administrative personnel data, and current events -- as well as minority opportunities from 8 participating federal agencies.

  7. Tabulated In-Drift Geometric and Thermal Properties Used In Drift-Scale Models for TSPA-SR

    SciTech Connect

    N.D. Francis

    2000-06-16

    The objective of this calculation is to provide in-drift physical properties required by the drift-scale models (both two- and three-dimensional) used in total system performance assessments (TSPA). The physical properties include waste package geometry, waste package thermal properties, emplacement drift geometry including backfill and invert geometry and properties (both thermal and hydrologic), drip shield geometry and thermal properties, all tabulated in a single source.

  8. Alternative methods for herbicide spray drift detection in corn and cotton

    NASA Astrophysics Data System (ADS)

    Buehring, Nathan Wade

    The acceptance of herbicide-resistant crops and the subsequent increase in glyphosate use throughout the growing season has led to increased problems with herbicide drift in corn and cotton. Potential yield losses due to herbicide spray drift cannot always be accurately assessed using visual ratings or by measuring reductions in plant height. This research was conducted to determine if other methods, such as biochemical assays or remote sensing, could be used to assess potential yield reductions and visual injury associated with herbicide drift. Other objectives included using hyperspectral and multispectral remote sensing for herbicide drift detection in corn and cotton. Classification accuracies were highest 14 DAA when distinguishing untreated from treated corn. When the data were classified by herbicides, overall accuracies of ≥74% resulted 14 and 28 DAA. Classifications based on yield reduction also resulted in highest overall classification accuracies 14 and 28 DAA, ranging from 69 to 70%. Within the glufosinate-treated corn, overall accuracies for classifying percent yield reductions was 85% at 3 DAA and decreased to 68% at 28 DAA. Overall classification accuracies for determining percent yield reductions with glyphosate were higher 14 and 28 DAA. With pyrithiobac, overall accuracies for determining percent yield reductions ranged from 73 to 82% across all evaluations. Of the nine vegetative indices tested to classify the data, Anthocyanin Reflective Index (ARI) and Chlorophyll Fluorescence Ratio of reflectance at 735 nm/700 nm (CF 735) were the most important for classifying, assessing, and detecting herbicide spray drift in corn. Multispectral aerial imagery was also used to identify cotton affected by a simulated bromoxynil drift event. Multispectral aerial imagery collected 9 DAA in 2002 resulted in better classification accuracies for identifying bromoxynil rate, percent visual injury, and percent yield reduction than imagery collected 21 DAA in 2001

  9. Drift effects on electromagnetic geodesic acoustic modes

    SciTech Connect

    Sgalla, R. J. F.

    2015-02-15

    A two fluid model with parallel viscosity is employed to derive the dispersion relation for electromagnetic geodesic acoustic modes (GAMs) in the presence of drift (diamagnetic) effects. Concerning the influence of the electron dynamics on the high frequency GAM, it is shown that the frequency of the electromagnetic GAM is independent of the equilibrium parallel current but, in contrast with purely electrostatic GAMs, significantly depends on the electron temperature gradient. The electromagnetic GAM may explain the discrepancy between the f ∼ 40 kHz oscillation observed in tokamak TCABR [Yu. K. Kuznetsov et al., Nucl. Fusion 52, 063044 (2012)] and the former prediction for the electrostatic GAM frequency. The radial wave length associated with this oscillation, estimated presently from this analytical model, is λ{sub r} ∼ 25 cm, i.e., an order of magnitude higher than the usual value for zonal flows (ZFs)

  10. New Pulsars from Arecibo Drift Scan Searches

    NASA Technical Reports Server (NTRS)

    McLaughlin, M. A.; Lorimer, D. R.; Arzoumanian, Z.; Backer, D. C.; Cordes, J. M.; Fruchter, A.; Lommen, A. N.; Xilouris, K.

    2003-01-01

    We report new pulsars discovered in drift-scan data taken by two collaborations (Berkeley/Cornell and STScI/NAIC) during the latter stages of the Arecibo upgrade period. The data were taken with the Penn State Pulsar Machine and are being processed on the COBRA cluster at Jodrell Bank. Processing is roughly 70% complete and has resulted in the detection of 10 new and 31 known pulsars, in addition to a number of pulsar candidates. The 10 new pulsars include one pulsar with a spin-period of 55 ms and another with a spin period of 5.8 ms. At the completion of the processing, we expect to have discovered roughly 20 new pulsars. All new pulsars are being subjected to a program of followup observations at Arecibo to determine spin and astrometric parameters.

  11. Drift effects on electromagnetic geodesic acoustic modes

    NASA Astrophysics Data System (ADS)

    Sgalla, R. J. F.

    2015-02-01

    A two fluid model with parallel viscosity is employed to derive the dispersion relation for electromagnetic geodesic acoustic modes (GAMs) in the presence of drift (diamagnetic) effects. Concerning the influence of the electron dynamics on the high frequency GAM, it is shown that the frequency of the electromagnetic GAM is independent of the equilibrium parallel current but, in contrast with purely electrostatic GAMs, significantly depends on the electron temperature gradient. The electromagnetic GAM may explain the discrepancy between the f ˜ 40 kHz oscillation observed in tokamak TCABR [Yu. K. Kuznetsov et al., Nucl. Fusion 52, 063044 (2012)] and the former prediction for the electrostatic GAM frequency. The radial wave length associated with this oscillation, estimated presently from this analytical model, is λr ˜ 25 cm, i.e., an order of magnitude higher than the usual value for zonal flows (ZFs).

  12. Drift-Kinetic Simulations of Neoclassical Transport

    SciTech Connect

    Belli, E. A.; Candy, J.

    2008-11-01

    We present results from numerical studies of neoclassical transport for multi-species plasmas. The code, NEO, provides a first-principles based calculation of the neoclassical transport coefficients directly from solution of the distribution function by solving a hierarchy of equations derived by expanding the fundamental drift-kinetic equation in powers of {rho}{sub *i}, the ratio of the ion gyroradius to system size. It extends previous studies by including the self-consistent coupling of electrons and multiple ion species and strong toroidal rotation effects. Systematic calculations of the second-order particle and energy fluxes and first-order plasma flows and bootstrap current and comparisons with existing theories are given for multi-species plasmas. The ambipolar relation {sigma}{sub a}z{sub a}{gamma}{sub a} = 0, which can only be maintained with complete cross-species collisional coupling, is confirmed. The effects of plasma shaping are also explored.

  13. Mixed Layer Drift Revealed by Satellite Data

    NASA Technical Reports Server (NTRS)

    Liu, Antony K.; Zhao, Yun-He; Esaias, Wayne E.; Campbell, Janet W.; Moore, Timothy; Koblinsky, Chester J. (Technical Monitor)

    2001-01-01

    For the first time we are able to derive ocean currents using the wavelet algorithm for feature tracking from two different sensors (MODIS and SeaWiFS) on different satellites. Satellite ocean color data provide an important insight to the marine biosphere because of their capability to quantify certain fundamental properties (such as phytoplankton pigment concentration, marine primary production, etc.) on a global basis. The mixed layer drift can be derived because the ocean color signal bears information from a much larger depth (10 to 30 meters) as compared with the sea surface temperature data. Although the drifter data are very limited in the study area, the comparison shows a general agreement between drifter data and satellite tracking results, especially for the cases near the Gulf Stream boundary.

  14. Evaporation drift of pesticides active ingredients.

    PubMed

    De Schampheleire, M; Nuyttens, D; De Keyser, D; Spanoghe, P

    2008-01-01

    Losses of pesticide active ingredients (a.i.) into the atmosphere can occur through several pathways. A main pathway is evaporation drift. The evaporation process of pesticide a.i., after application, is affected by three main factors: Physicochemical properties of the pesticide a.i., weather conditions and crop structure. The main physicochemical parameters are the Henry coefficient, which is a measure for the volatilization tendency of the pesticide a.i. from a dilute aqueous solution, and the vapour pressure, which is a measure for the volatilization tendency of the pesticide a.i. from the solid phase. Five pesticide a.i., with various Henry coefficients and various vapour pressures, were selected to conduct laboratory experiments: metalaxyl-m, dichlorovos, diazinon, Lindane and trifluralin. Evaporation experiments were conducted in a volatilization chamber. It was found that the evaporation tendencies significantly differed according to the physicochemical properties of the a.i. PMID:19226822

  15. Two Dimensional Inhomogeneous Magnetic Electron Drift Modes

    SciTech Connect

    Shaikh, Dastgeer; Eliasson, Bengt; Shukla, P. K.

    2009-11-10

    We present simulations of the magnetic electron drift vortex (MEDV) mode turbulence in a magnetoplasma in the presence of inhomogeneities in the plasma temperature and density, as well as in the external magnetic field. The study shows that the influence of the magnetic field in-homogeneity is to suppress streamer-like structures observed in previous simulation studies without background magnetic fields. The MEDV mode turbulence exhibits non-universal (non-Kolmogorov type) spectra for different sets of the plasma parameters. In the presence of an inhomogeneous magnetic field, the spectrum changes to a 7/3 power law, which is flatter than without magnetic field gradients. The relevance of this work to laboratory and cosmic plasmas is briefly mentioned.

  16. Nonlinear analysis of the gradient drift instability

    NASA Astrophysics Data System (ADS)

    González, Rafael; Vega, Matías de la

    An analytical study of the gradient drift instability in the equatorial electrojet of wavelengths in the order of one kilometer is presented. Different mechanisms, linear, non-local and turbulent, are found in the literature to explain the predominance of the 1 km wavelength in the electrojet. In the present work a simplified model is proposed in which the nonlinear evolution of three coupled modes is followed. By considering that one of the modes attains the stationary state, the evolution of the other two is obtained, and it is found that they follow equations of the Lotka-Volterra type. A stable stationary nonlinear solution for these equations is also found, and the conditions under which periodic solutions are possible are analyzed.

  17. Anomalous phase shifts in drift wave fluctuations

    NASA Astrophysics Data System (ADS)

    Diallo, Ahmed; Skiff, Fred

    2003-10-01

    Ion phase space density fluctuation measurements are performed in a linearly magnetized device using Laser Induced Fluorescence(LIF). An ICP source produces an 8cm diameter plasma column that drifts in a cylindrical vessel whose diameter and length are 40 cm and 3 m, respectively. These experiments are performed using a CW singly ionized Argon plasma that is immersed in a 1kG magnetic field along the axis of the cylinder. A density of the order of 10^9 cm-3 is obtained under a regulated neutral background pressure of 2.× 10-4 torr. The electron and ion temperature are respectively 2 eV and 0.1 eV. LIF is carried out by pumping the Ar II metastable (3d^1)^2G_9/2, using a CW tunable laser centered at 611.6653 nm scanned over 6 GHz, to metastable (4p^1)F_7/2, and then detecting the 460nm photons emitted from its transition to (4s^1)^2F_5/2. This collection is made possible using two low f-umber periscopes that are directed to PMTs. Here we present measurements of the complex two-point correlation function < f(v_i_allel),z_1,ω)f(v_i_allel,z_2,ω)> as a function of the spatial separation of two LIF detection systems Δ d = z_2-z_1, the ion parallel velocity v_i_allel and the frequency ω. Preliminary results show ion particle velocity dependent phase shifts at the drift wave frequency.

  18. Hemodialysis access - self care

    MedlinePlus

    Kidney failure - chronic-hemodialysis access; Renal failure - chronic-hemodialysis access; Chronic renal insufficiency - hemodialysis access; Chronic kidney failure - hemodialysis access; Chronic renal failure - hemodialysis access; dialysis - hemodialysis access

  19. Magnetopause structure and the question of particle accessibility

    NASA Technical Reports Server (NTRS)

    Whipple, E. C.; Hill, J. R.; Nichols, J. D.

    1984-01-01

    A simple plane model of the magnetopause is used to address the question of particle accessibility. Particle motion in the current sheet region is analyzed, showing that the concept of gyromotion is useful even when the electric and magnetic fields vary significantly over the gyroradius, as long as the variation is perpendicular to the drift direction. The first adiabatic invariant for particle motion is defined in such a way that it is preserved in regions of large field gradients, provided that the gradients are in a direction primarily perpendicular to the particle drifts. This generalized invariant provides an adiabatically conserved quantity that can be used to characterize particles as they move from a source region through the drift region and into the magnetopause itself, helping to resolve the accessibility question. Some preliminary results are given for the magnetopause structure based on the location of particle guiding points.

  20. In-Drift Microbial Communities Model Validation Calculations

    SciTech Connect

    D. M. Jolley

    2001-09-24

    The objective and scope of this calculation is to create the appropriate parameter input for MING 1.0 (CSCI 30018 V1.0, CRWMS M&O 1998b) that will allow the testing of the results from the MING software code with both scientific measurements of microbial populations at the site and laboratory and with natural analogs to the site. This set of calculations provides results that will be used in model validation for the ''In-Drift Microbial Communities'' model (CRWMS M&O 2000) which is part of the Engineered Barrier System Department (EBS) process modeling effort that eventually will feed future Total System Performance Assessment (TSPA) models. This calculation is being produced to replace MING model validation output that is effected by the supersession of DTN MO9909SPAMING1.003 using its replacement DTN MO0106SPAIDM01.034 so that the calculations currently found in the ''In-Drift Microbial Communities'' AMR (CRWMS M&O 2000) will be brought up to date. This set of calculations replaces the calculations contained in sections 6.7.2, 6.7.3 and Attachment I of CRWMS M&O (2000) As all of these calculations are created explicitly for model validation, the data qualification status of all inputs can be considered corroborative in accordance with AP-3.15Q. This work activity has been evaluated in accordance with the AP-2.21 procedure, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities'', and is subject to QA controls (BSC 2001). The calculation is developed in accordance with the AP-3.12 procedure, Calculations, and prepared in accordance with the ''Technical Work Plan For EBS Department Modeling FY 01 Work Activities'' (BSC 2001) which includes controls for the management of electronic data.