Science.gov

Sample records for indirect detection experiments

  1. The muon-induced neutron indirect detection EXperiment, MINIDEX

    NASA Astrophysics Data System (ADS)

    Abt, I.; Caldwell, A.; Carissimo, C.; Gooch, C.; Kneißl, R.; Langford, J.; Liu, X.; Majorovits, B.; Palermo, M.; Schulz, O.; Vanhoefer, L.

    2017-04-01

    A new experiment to quantitatively measure neutrons induced by cosmic-ray muons in selected high-Z materials is introduced. The design of the Muon-Induced Neutron Indirect Detection EXperiment, MINIDEX, and the results from its first data taking period are presented as well as future plans. Neutron production in high-Z materials is of particular interest as such materials are used for shielding in low-background experiments. The design of next-generation large-scale experiments searching for neutrinoless double beta decay or direct interactions of dark matter requires reliable Monte Carlo simulations of background induced by muon interactions. The first five months of operation already provided a valuable data set on neutron production and neutron transport in lead. A first round of comparisons between MINIDEX data and Monte Carlo predictions obtained with a GEANT4-based package for two different sets of physics models of relevance for neutron production by muons is presented. The rate of muon-induced events is overall a factor three to four higher in data than predicted by the Monte Carlo packages. In addition, the time evolution of the muon-induced signal is not well described by the simulations.

  2. SUSY under siege from direct and indirect WIMP detection experiments

    NASA Astrophysics Data System (ADS)

    Baer, Howard; Barger, Vernon; Serce, Hasan

    2016-12-01

    We examine updated prospects for detecting WIMPs in supersymmetric models via direct and indirect dark matter search experiments. We examine several historical and also still viable scenarios: projections for well-tempered neutralinos (WTN), projections from the MasterCode (MC), BayesFits (BF) and Fittino (FO) collaborations, nonthermal wino dark matter (NThW) and finally mixed axion-Higgsino dark matter from SUSY with radiatively driven naturalness (RNS). The WTN is ruled out by recent limits from XENON and LUX collaborations. The NThW scenario, previously on tenuous ground due to gamma-line searches, appears also ruled out by recent combined Fermi-LAT/MAGIC limits combined with new HESS results from continuum gamma rays. Substantial portions of MC parameter space and 1 TeV Higgsino parameter space from BF group are ruled out. The 100-300 GeV Higgsino-like WIMP from RNS survives due to its possible depleted local abundance (where the axion may make up the bulk of dark matter). Projections from ton-scale noble liquid detectors should discover or rule out WIMPs from the remaining parameter space of these surviving models.

  3. Indirect microbial detection

    NASA Technical Reports Server (NTRS)

    Wilkins, J. R.

    1980-01-01

    Indirect method for detection of microbial growth utilizes flow of charged particles across barrier that physically separated growing cells from electrodes and measures resulting difference in potential between two platinum electrodes. Technique allows simplified noncontact monitoring of all growth in highly infectious cultures or in critical biochemical studies.

  4. Indirect microbial detection

    NASA Technical Reports Server (NTRS)

    Wilkins, J. R. (Inventor)

    1981-01-01

    The growth of microorganisms in a sample is detected and monitored by culturing microorganisms in a growth medium and detecting a change in potential between two electrodes, separated from the microbial growth by a barrier which is permeable to charged paticles but microorganism impermeable.

  5. Indirect Reciprocity; A Field Experiment.

    PubMed

    van Apeldoorn, Jacobien; Schram, Arthur

    2016-01-01

    Indirect reciprocity involves cooperative acts towards strangers, either in response to their kindness to third parties (downstream) or after receiving kindness from others oneself (upstream). It is considered to be important for the evolution of cooperative behavior amongst humans. Though it has been widely studied theoretically, the empirical evidence of indirect reciprocity has thus far been limited and based solely on behavior in laboratory experiments. We provide evidence from an online environment where members can repeatedly ask and offer services to each other, free of charge. For the purpose of this study we created several new member profiles, which differ only in terms of their serving history. We then sent out a large number of service requests to different members from all over the world. We observe that a service request is more likely to be rewarded for those with a profile history of offering the service (to third parties) in the past. This provides clear evidence of (downstream) indirect reciprocity. We find no support for upstream indirect reciprocity (in this case, rewarding the service request after having previously received the service from third parties), however. Our evidence of downstream indirect reciprocity cannot be attributed to reputational effects concerning one's trustworthiness as a service user.

  6. Indirect Reciprocity; A Field Experiment

    PubMed Central

    van Apeldoorn, Jacobien; Schram, Arthur

    2016-01-01

    Indirect reciprocity involves cooperative acts towards strangers, either in response to their kindness to third parties (downstream) or after receiving kindness from others oneself (upstream). It is considered to be important for the evolution of cooperative behavior amongst humans. Though it has been widely studied theoretically, the empirical evidence of indirect reciprocity has thus far been limited and based solely on behavior in laboratory experiments. We provide evidence from an online environment where members can repeatedly ask and offer services to each other, free of charge. For the purpose of this study we created several new member profiles, which differ only in terms of their serving history. We then sent out a large number of service requests to different members from all over the world. We observe that a service request is more likely to be rewarded for those with a profile history of offering the service (to third parties) in the past. This provides clear evidence of (downstream) indirect reciprocity. We find no support for upstream indirect reciprocity (in this case, rewarding the service request after having previously received the service from third parties), however. Our evidence of downstream indirect reciprocity cannot be attributed to reputational effects concerning one’s trustworthiness as a service user. PMID:27043712

  7. Cosmic Ray Experiments and the Implications for Indirect Detection of Dark Matter

    NASA Technical Reports Server (NTRS)

    Mitchell, John W.; Ormes, Jonathan F.; Streitmatter, Robert E.

    2013-01-01

    Detection of cosmic-ray antiprotons was first reported by Golden et al. in 1979 and their existence was firmly established by the BESS and IMAX collaborations in the early 1990s. Increasingly precise measurements of the antiproton spectrum, most recently from BESS-Polar and PAMELA, have made it an important tool for investigating cosmic-ray transport in the galaxy and heliosphere and for constraining dark-matter models. The history of antiproton measurements will be briefly reviewed. The current status will be discussed, focusing on the results of BESS-Polar II and their implications for the possibility of antiprotons from primordial black hole evaporation. The current results of the BESS-Polar II antihelium search are also presented.

  8. Capillary electrophoresis with indirect amperometric detection.

    PubMed

    Olefirowicz, T M; Ewing, A G

    1990-01-19

    The use of indirect amperometric detection with capillary electrophoresis is demonstrated. The system consists of a porous glass coupler which allows amperometric detection at a carbon fiber electrode placed in the end of the capillary. 3,4-Dihydroxybenzylamine is added to the buffer system as a continuously eluting electrophore. Indirect amperometric detection in 9-mumol I.D. capillaries provides detection limits as low as 380 attomole for the amino acid arginine. Finally, both direct and indirect amperometric detection can be accomplished simultaneously.

  9. Remote Leak Detection: Indirect Thermal Technique

    NASA Technical Reports Server (NTRS)

    Clements, Sandra

    2002-01-01

    Remote sensing technologies are being considered for efficient, low cost gas leak detection. Eleven specific techniques have been identified for further study and evaluation of several of these is underway. The Indirect Thermal Technique is one of the techniques that is being explored. For this technique, an infrared camera is used to detect the temperature change of a pipe or fitting at the site of a gas leak. This temperature change is caused by the change in temperature of the gas expanding from the leak site. During the 10-week NFFP program, the theory behind the technique was further developed, experiments were performed to determine the conditions for which the technique might be viable, and a proof-of-concept system was developed and tested in the laboratory.

  10. Dark matter dynamics and indirect detection

    SciTech Connect

    Bertone, Gianfranco; Merritt, David; /Rochester Inst. Tech.

    2005-04-01

    Non-baryonic, or ''dark'', matter is believed to be a major component of the total mass budget of the universe. We review the candidates for particle dark matter and discuss the prospects for direct detection (via interaction of dark matter particles with laboratory detectors) and indirect detection (via observations of the products of dark matter self-annihilations), focusing in particular on the Galactic center, which is among the most promising targets for indirect detection studies. The gravitational potential at the Galactic center is dominated by stars and by the supermassive black hole, and the dark matter distribution is expected to evolve on sub-parsec scales due to interaction with these components. We discuss the dominant interaction mechanisms and show how they can be used to rule out certain extreme models for the dark matter distribution, thus increasing the information that can be gleaned from indirect detection searches.

  11. Indirect neutralino detection rates in neutrino telescopes

    SciTech Connect

    Bergstroem, L.; Edsjoe, J.; Gondolo, P.

    1997-02-01

    Neutralinos annihilating in the center of the Sun or the Earth may give rise to a detectable signal of neutrinos. We derive the indirect detection rates for neutrino telescopes in the minimal supersymmetric extension of the standard model. We show that even after imposing all phenomenological and experimental constraints that make the theories viable, regions of parameter space exist which can already be probed by existing neutrino telescopes. We compare with the discovery potential of supersymmetry at CERN LEP 2 as well as direct detections and point out the complementarity of the methods. {copyright} {ital 1997} {ital The American Physical Society}

  12. Indirect fluorometric detection in gel electrophysics

    SciTech Connect

    Hogan, B. L.; Yeung, E. S.

    1989-02-01

    Polyacrylamide gel electrophoresis separates biomolecules by virtueof their inherent charge or size, or a combination of the two. Thiswidely used bioanalytical technique has seen applications in areassuch as the separation of complex mixtures of proteins, gene sequenchingand mapping, and clinical diagnosis. The method displays unmatchedresolution of macromolecules, yet still utilizes detection methods which areslow and labor/minus/intensive. Commonly used methods such as Coomassie Blue andsilver staining can become complicated and may require twenty-four hoursto allow one to visualize the analyte. Autoradiography offers highsensitivity (10--100 pg)for the detection of radio-labelled analytes, butrequires exposure times of hours or days. A sensitive, yet rapid,quantitation method for electrophoresis would be quite useful. This paperdemonstrates the feasibility of employing indirect fluorometry as a rapidand potentially highly sensitive detection scheme for gelelectrophoresis. (AIP)

  13. Indirect detection methods: Looking for what is not there

    SciTech Connect

    Yeung, E.S. )

    1989-04-01

    Indirect detection allows one to monitor species that normally do not give a response. It has grown from an intellectual curiosity to become an extremely useful tool. For volume displacement, polarimetry gives the best results. For charge displacement, ion chromatography and capillary zone electrophoresis are ideal situations for applying indirect fluorescence detection. LOD surpasses all but the most specialized detection schemes. Future developments in systems specially designed for indirect detection should make these schemes even more powerful.

  14. Spherical cows in dark matter indirect detection

    NASA Astrophysics Data System (ADS)

    Bernal, Nicolás; Necib, Lina; Slatyer, Tracy R.

    2016-12-01

    Dark matter (DM) halos have long been known to be triaxial, but in studies of possible annihilation and decay signals they are often treated as approximately spherical. In this work, we examine the asymmetry of potential indirect detection signals of DM annihilation and decay, exploiting the large statistics of the hydrodynamic simulation Illustris. We carefully investigate the effects of the baryons on the sphericity of annihilation and decay signals for both the case where the observer is at 8.5 kpc from the center of the halo (exemplified in the case of Milky Way-like halos), and for an observer situated well outside the halo. In the case of Galactic signals, we find that both annihilation and decay signals are expected to be quite symmetric, with axis ratios very different from 1 occurring rarely. In the case of extragalactic signals, while decay signals are still preferentially spherical, the axis ratio for annihilation signals has a much flatter distribution, with elongated profiles appearing frequently. Many of these elongated profiles are due to large subhalos and/or recent mergers. Comparing to gamma-ray emission from the Milky Way and X-ray maps of clusters, we find that the gamma-ray background appears less spherical/more elongated than the expected DM signal from the large majority of halos, and the Galactic gamma ray excess appears very spherical, while the X-ray data would be difficult to distinguish from a DM signal by elongation/sphericity measurements alone.

  15. (In)Direct detection of boosted dark matter

    NASA Astrophysics Data System (ADS)

    Agashe, Kaustubh; Cui, Yanou; Necib, Lina; Thaler, Jesse

    2016-05-01

    We present a new multi-component dark matter model with a novel experimental signature that mimics neutral current interactions at neutrino detectors. In our model, the dark matter is composed of two particles, a heavier dominant component that annihilates to produce a boosted lighter component that we refer to as boosted dark matter. The lighter component is relativistic and scatters off electrons in neutrino experiments to produce Cherenkov light. This model combines the indirect detection of the dominant component with the direct detection of the boosted dark matter. Directionality can be used to distinguish the dark matter signal from the atmospheric neutrino background. We discuss the viable region of parameter space in current and future experiments.

  16. Direct and indirect detection of dissipative dark matter

    SciTech Connect

    Fan, JiJi; Katz, Andrey; Shelton, Jessie E-mail: katz.andrey@gmail.com

    2014-06-01

    We study the constraints from direct detection and solar capture on dark matter scenarios with a subdominant dissipative component. This dissipative dark matter component in general has both a symmetric and asymmetric relic abundance. Dissipative dynamics allow this subdominant dark matter component to cool, resulting in its partial or total collapse into a smaller volume inside the halo (e.g., a dark disk) as well as a reduced thermal velocity dispersion compared to that of normal cold dark matter. We first show that these features considerably relax the limits from direct detection experiments on the couplings between standard model (SM) particles and dissipative dark matter. On the other hand, indirect detection of the annihilation of the symmetric dissipative dark matter component inside the Sun sets stringent and robust constraints on the properties of the dissipative dark matter. In particular, IceCube observations force dissipative dark matter particles with mass above 50 GeV to either have a small coupling to the SM or a low local density in the solar system, or to have a nearly asymmetric relic abundance. Possible helioseismology signals associated with purely asymmetric dissipative dark matter are discussed, with no present constraints.

  17. Complementarity of direct dark matter detection and indirect detection through gamma rays

    SciTech Connect

    Bergstroem, Lars; Bringmann, Torsten; Edsjoe, Joakim

    2011-02-15

    We show, by using an extensive sample of viable supersymmetric models as templates, that indirect detection of dark matter through gamma rays may have a large potential for identifying the nature of dark matter. This is, in particular, true also for models that give too weak dark matter-nucleon scattering cross sections to be probed by present and planned direct detection experiments. Also models with a mass scale too high to be accessible at CERN's LHC accelerator may show up in next-generation imaging Cherenkov telescope arrays. Based on our findings, we therefore suggest to view indirect searches as genuine particle physics experiments, complementing other strategies to probe so far unknown regions in the parameter space of e.g. supersymmetric models, and propose a new approach that would make use of telescopes dedicated for dark matter searches. As a concrete example for the potential of such an approach, we consider an array of imaging air Cherenkov telescopes, the Dark Matter Array (DMA), and show that such an experiment could extend present-day limits by several orders of magnitude, reaching a large class of models that would remain undetected in both direct detection experiments and searches at the LHC. In addition, in a sizable part of the parameter space, signals from more than one type of dark matter detection experiment would be possible, something that may eventually be necessary in order to identify the dark matter candidate.

  18. Indirect detections and analyses of GRBs by ionospheric response

    SciTech Connect

    Slosiar, R.; Hudec, R.

    2009-05-25

    We report on the independent and indirect detection of GRBs by their ionospheric response (SID--Sudden Ionospheric Disturbance) observed at VLF (Very Low Frequency), and discus its possible impact on GRB science and investigations in general. Although few such detections have been already reported in the past, the capability of such alternative and indirect investigations of GRBs still remains to be investigated in more details. We present and discuss examples of such VLF/SID detection of GRBs 060124A, GRB080319D a GRB080320A. A network of SID monitors has been created and is operated to detect more GRBs. The importance of these detections for GRB analyses and GRB science in general is still to be further and in full detail exploited. Some possible outcomes in this direction will be outlined and discussed.

  19. Indirect Immunofluorescence for the Detection of Autoimmune Urticaria.

    PubMed

    Bahrani, Bahar; Gattey, Natasha T; Hull, Peter R

    2016-01-01

    An autoimmune basis is believed to be responsible for about half of chronic spontaneous urticaria (CSU) cases. The autologous serum skin test is used as a possible indicator, but there is currently no test that directly indicates an autoimmune etiology. In this study, an indirect immunofluorescence was used to identify patients with autoantibodies directed at mast cells. Two substrates were used including paraffin embedded sections of skin biopsies from an infant with bullous mastocytosis and cord blood-derived mast cells (CBMC). Sera from 76 patients with CSU were incubated with substrates and conjugated with human IgG. Using the bullous mastocytosis preparations, positive indirect immunofluorescence was found in 46% (n = 76), while the CBMC substrate was positive in 39% (n = 70). The IgG autoantibodies directed at mast cells could be detected in about half the patients with CSU. Indirect immunofluorescence should be considered as an indicator of the autoimmune form of CSU. © The Author(s) 2015.

  20. The focal account: Indirect lie detection need not access unconscious, implicit knowledge.

    PubMed

    Street, Chris N H; Richardson, Daniel C

    2015-12-01

    People are poor lie detectors, but accuracy can be improved by making the judgment indirectly. In a typical demonstration, participants are not told that the experiment is about deception at all. Instead, they judge whether the speaker appears, say, tense or not. Surprisingly, these indirect judgments better reflect the speaker's veracity. A common explanation is that participants have an implicit awareness of deceptive behavior, even when they cannot explicitly identify it. We propose an alternative explanation. Attending to a range of behaviors, as explicit raters do, can lead to conflict: A speaker may be thinking hard (indicating deception) but not tense (indicating honesty). In 2 experiments, we show that the judgment (and in turn the correct classification rate) is the result of attending to a single behavior, as indirect raters are instructed to do. Indirect lie detection does not access implicit knowledge, but simply focuses the perceiver on more useful cues. (c) 2015 APA, all rights reserved).

  1. Indirect Detection Analysis: Wino Dark Matter Case Study

    SciTech Connect

    Hryczuk, Andrzej; Cholis, Ilias; Iengo, Roberto; Tavakoli, Maryam; Ullio, Piero

    2014-07-15

    We perform a multichannel analysis of the indirect signals for the Wino Dark Matter, including one-loop electroweak and Sommerfeld enhancement corrections. We derive limits from cosmic ray antiprotons and positrons, from continuum galactic and extragalactic diffuse γ-ray spectra, from the absence of γ-ray line features at the galactic center above 500 GeV in energy, from γ-rays toward nearby dwarf spheroidal galaxies and galaxy clusters, and from CMB power-spectra. Additionally, we show the future prospects for neutrino observations toward the inner Galaxy and from antideuteron searches. For each of these indirect detection probes we include and discuss the relevance of the most important astrophysical uncertainties that can impact the strength of the derived limits. We find that the Wino as a dark matter candidate is excluded in the mass range bellow simeq 800 GeV from antiprotons and between 1.8 and 3.5 TeV from the absence of a γ-ray line feature toward the galactic center. Limits from other indirect detection probes confirm the main bulk of the excluded mass ranges.

  2. Indirect detection analysis: wino dark matter case study

    SciTech Connect

    Hryczuk, Andrzej; Cholis, Ilias; Iengo, Roberto; Ullio, Piero; Tavakoli, Maryam E-mail: cholis@fnal.gov E-mail: maryam.tavakoli@desy.de

    2014-07-01

    We perform a multichannel analysis of the indirect signals for the Wino Dark Matter, including one-loop electroweak and Sommerfeld enhancement corrections. We derive limits from cosmic ray antiprotons and positrons, from continuum galactic and extragalactic diffuse γ-ray spectra, from the absence of γ-ray line features at the galactic center above 500 GeV in energy, from γ-rays toward nearby dwarf spheroidal galaxies and galaxy clusters, and from CMB power-spectra. Additionally, we show the future prospects for neutrino observations toward the inner Galaxy and from antideuteron searches. For each of these indirect detection probes we include and discuss the relevance of the most important astrophysical uncertainties that can impact the strength of the derived limits. We find that the Wino as a dark matter candidate is excluded in the mass range bellow ≅ 800 GeV from antiprotons and between 1.8 and 3.5 TeV from the absence of a γ-ray line feature toward the galactic center. Limits from other indirect detection probes confirm the main bulk of the excluded mass ranges.

  3. The Indirect Detection of GRBs by Ionospheric Response - Detection of GRB060124A

    SciTech Connect

    Slosiar, Rudolf; Hudec, Rene

    2008-05-22

    We report on the independent and indirect detection of GRBs by their ionospheric response (SID-Sudden Ionospheric Disturbance) observed at VLF (Very Low Frequency). Although few such detections have been already reported in the past, the capability of such alternative and indirect investigations of GRBs still remains to be investigated in more details. We present and discuss an example of such VLF/SID detection of the GRB 060124A.

  4. Direct and Indirect Dark Matter Detection in Gauge Theories

    SciTech Connect

    Queiroz, Farinaldo

    2013-01-01

    The Dark matter (DM) problem constitutes a key question at the interface among Particle Physics, Astrophysics and Cosmology. The observational data which have been accumulated in the last years point to an existence of non baryonic amount of DM. Since the Standard Model (SM) does not provide any candidate for such non-baryonic DM, the evidence of DM is a major indication for new physics beyond the SM. We will study in this work one of the most popular DM candidates, the so called WIMPs (Weakly Interacting Massive Particles) from a direct and indirect detection perspective. In order to approach the direct and indirect dection of DM in the context of Particle Physics in a more pedagogic way, we will begin our discussion talking about a minimal extension of the SM. Later we will work on the subject in a 3-3-1 model. Next, we will study the role of WIMPs in the Big Bang Nucleosynthesis. Lastly, we will look for indirect DM signals in the center of our galaxy using the NASA Satellite, called Fermi-LAT. Through a comprehensive analysis of the data events observed by Fermi-LAT and some background models, we will constrain the dark matter annihilation cross section for several annihilation channels and dark matter halo profiles.

  5. Indirect detection of radiation sources through direct detection of radiolysis products

    DOEpatents

    Farmer, Joseph C [Tracy, CA; Fischer, Larry E [Los Gatos, CA; Felter, Thomas E [Livermore, CA

    2010-04-20

    A system for indirectly detecting a radiation source by directly detecting radiolytic products. The radiation source emits radiation and the radiation produces the radiolytic products. A fluid is positioned to receive the radiation from the radiation source. When the fluid is irradiated, radiolytic products are produced. By directly detecting the radiolytic products, the radiation source is detected.

  6. Indirect fluorometric detection techniques on thin layer chromatography and effect of ultrasound on gel electrophoresis

    SciTech Connect

    Yinfa, Ma.

    1990-12-10

    Thin-layer chromatography (TLC) is a broadly applicable separation technique. It offers many advantages over high performance liquid chromatography (HPLC), such as easily adapted for two-dimensional separation, for whole-column'' detection and for handling multiple samples, etc. However, due to its draggy development of detection techniques comparing with HPLC, TLC has not received the attention it deserves. Therefore, exploring new detection techniques is very important to the development of TLC. It is the principal of this dissertation to present a new detection method for TLC -- indirect fluorometric detection method. This detection technique is universal sensitive, nondestructive, and simple. This will be described in detail from Sections 1 through Section 5. Section 1 and 3 describe the indirect fluorometric detection of anions and nonelectrolytes in TLC. In Section 2, a detection method for cations based on fluorescence quenching of ethidium bromide is presented. In Section 4, a simple and interesting TLC experiment is designed, three different fluorescence detection principles are used for the determination of caffeine, saccharin and sodium benzoate in beverages. A laser-based indirect fluorometric detection technique in TLC is developed in Section 5. Section 6 is totally different from Sections 1 through 5. An ultrasonic effect on the separation of DNA fragments in agarose gel electrophoresis is investigated. 262 refs.

  7. Indirect detection of dark matter with γ rays

    NASA Astrophysics Data System (ADS)

    Funk, Stefan

    2015-10-01

    The details of what constitutes the majority of the mass that makes up dark matter in the Universe remains one of the prime puzzles of cosmology and particle physics today - eighty years after the first observational indications. Today, it is widely accepted that dark matter exists and that it is very likely composed of elementary particles - that are weakly interacting and massive (WIMPs for Weakly Interacting Massive Particles). As important as dark matter is in our understanding of cosmology, the detection of these particles has so far been elusive. Their primary properties such as mass and interaction cross sections are still unknown. Indirect detection searches for the products of WIMP annihilation or decay. This is generally done through observations of gamma-ray photons or cosmic rays. Instruments such as the Fermi-LAT, H.E.S.S., MAGIC and VERITAS, combined with the future Cherenkov Telescope Array (CTA) will provide important and complementary constraints to other search techniques. Given the expected sensitivities of all search techniques, we are at a stage where the WIMP scenario is facing stringent tests and it can be expected that WIMPs will be either be detected or the scenario will be so severely constrained that it will have to be re-thought. In this sense we are on the "Threshold of Discovery". In this article, I will give a general overview over the current status and the future expectations for indirect searches for dark matter (WIMP) particles.

  8. Indirect detection of dark matter with γ rays.

    PubMed

    Funk, Stefan

    2015-10-06

    The details of what constitutes the majority of the mass that makes up dark matter in the Universe remains one of the prime puzzles of cosmology and particle physics today-80 y after the first observational indications. Today, it is widely accepted that dark matter exists and that it is very likely composed of elementary particles, which are weakly interacting and massive [weakly interacting massive particles (WIMPs)]. As important as dark matter is in our understanding of cosmology, the detection of these particles has thus far been elusive. Their primary properties such as mass and interaction cross sections are still unknown. Indirect detection searches for the products of WIMP annihilation or decay. This is generally done through observations of γ-ray photons or cosmic rays. Instruments such as the Fermi large-area telescope, high-energy stereoscopic system, major atmospheric gamma-ray imaging Cherenkov, and very energetic radiation imaging telescope array, combined with the future Cherenkov telescope array, will provide important complementarity to other search techniques. Given the expected sensitivities of all search techniques, we are at a stage where the WIMP scenario is facing stringent tests, and it can be expected that WIMPs will be either be detected or the scenario will be so severely constrained that it will have to be rethought. In this sense, we are on the threshold of discovery. In this article, I will give a general overview of the current status and future expectations for indirect searches of dark matter (WIMP) particles.

  9. Indirect detection of dark matter with γ rays

    PubMed Central

    Funk, Stefan

    2015-01-01

    The details of what constitutes the majority of the mass that makes up dark matter in the Universe remains one of the prime puzzles of cosmology and particle physics today—80 y after the first observational indications. Today, it is widely accepted that dark matter exists and that it is very likely composed of elementary particles, which are weakly interacting and massive [weakly interacting massive particles (WIMPs)]. As important as dark matter is in our understanding of cosmology, the detection of these particles has thus far been elusive. Their primary properties such as mass and interaction cross sections are still unknown. Indirect detection searches for the products of WIMP annihilation or decay. This is generally done through observations of γ-ray photons or cosmic rays. Instruments such as the Fermi large-area telescope, high-energy stereoscopic system, major atmospheric gamma-ray imaging Cherenkov, and very energetic radiation imaging telescope array, combined with the future Cherenkov telescope array, will provide important complementarity to other search techniques. Given the expected sensitivities of all search techniques, we are at a stage where the WIMP scenario is facing stringent tests, and it can be expected that WIMPs will be either be detected or the scenario will be so severely constrained that it will have to be rethought. In this sense, we are on the threshold of discovery. In this article, I will give a general overview of the current status and future expectations for indirect searches of dark matter (WIMP) particles. PMID:24821791

  10. Direct/indirect detection signatures of nonthermally produced dark matter

    SciTech Connect

    Nagai, Minoru; Nakayama, Kazunori

    2008-09-15

    We study direct and indirect detection possibilities of neutralino dark matter produced nonthermally by, e.g., the decay of long-lived particles, as is easily implemented in the case of anomaly or mirage-mediation models. In this scenario, large self-annihilation cross sections are required to account for the present dark matter abundance, and it leads to significant enhancement of the gamma-ray signature from the galactic center and the positron flux from the dark matter annihilation. It is found that GLAST and PAMELA will find the signal or give tight constraints on such nonthermal production scenarios of neutralino dark matter.

  11. Autoantibody detection using indirect immunofluorescence on HEp-2 cells.

    PubMed

    Sack, Ulrich; Conrad, Karsten; Csernok, Elena; Frank, Ingrid; Hiepe, Falk; Krieger, Thorsten; Kromminga, Arno; von Landenberg, Philipp; Messer, Gerald; Witte, Torsten; Mierau, Rudolf

    2009-09-01

    The detection of autoantibodies is an important element in the diagnosis and monitoring of disease progression in patients with autoimmune diseases. In laboratory diagnostic tests for connective tissue and autoimmune liver diseases, indirect immunofluorescence on HEp-2 cells plays a central role in a multistage diagnostic process. Despite the high quality of diagnostics, findings at different laboratories can differ considerably due to a lack of standardization, as well as subjective factors. The present paper formulates recommendations for the standardized processing and interpretation of the HEp-2 cell test for the detection of non-organ-specific (especially antinuclear) antibodies. It provides requirements regarding the diagnostic tests used, instructions for laboratory procedure and evaluation, and recommendations for interpretation. For an optimal laboratory diagnostic process, it is useful to have an informative, tentative clinical diagnosis and an experienced laboratory diagnostician. In addition, the following key elements are recommended: initial screening using indirect immunofluorescence on carefully chosen HEp-2 cells beginning with a serum dilution of 1:80 and evaluation under a microscope with powerful illumination; results from a titer of 1:160 upwards being considered positive; internal laboratory quality control; and standardized interpretation. The aim is to improve diagnostic tests and care of patients with autoimmune diseases as a central concern of the European Autoimmunity Standardization Initiative (EASI).

  12. Beryllium ignition target design for indirect drive NIF experiments

    NASA Astrophysics Data System (ADS)

    Simakov, A. N.; Wilson, D. C.; Yi, S. A.; Kline, J. L.; Salmonson, J. D.; Clark, D. S.; Milovich, J. L.; Marinak, M. M.

    2016-03-01

    Beryllium (Be) ablator offers multiple advantages over carbon based ablators for indirectly driven NIF ICF ignition targets. These are higher mass ablation rate, ablation pressure and ablation velocity, lower capsule albedo, and higher thermal conductivity at cryogenic temperatures. Such advantages can be used to improve the target robustness and performance. While previous NIF Be target designs exist, they were obtained a long time ago and do not incorporate the latest improved physical understanding and models based upon NIF experiments. Herein, we propose a new NIF Be ignition target design at 1.45 MJ, 430 TW that takes all this knowledge into account.

  13. Numerical Simulation of Indirect-Drive Tracer Diagnostic Experiments

    NASA Astrophysics Data System (ADS)

    Macfarlane, J. J.; Cohen, D. H.; Wang, P.; Jaanimagi, P.; Back, C. A.; Landen, O. L.; Turner, R. E.; Oertel, J. A.; Nash, T. J.

    1998-11-01

    We have performed indirect-drive experiments at the OMEGA (U. Rochester) and NOVA (LLNL) laser facilities to study the use of tracer emission and absorption spectroscopy in characterizing radiatively-driven materials. In these experiments, thin ( ~ 3000 Åthick) tracer layers of KCl, KF, and NaCl were embedded in ~ 50 -- 100 μm-thick Al and Ge-doped CH ``witness plates'' which were attached to the side of cylindrical Au hohlraums. In most cases the hohlraums were irradiated with 12 -- 25 TW, 1 ns square laser pulses, which generate a high-TR radiation drive (TR ≈ 200 eV). In some experiments, shaped laser pulses were used. The radiation wave burns into the witness plate, heating the tracer to temperatures of 100 -- 200 eV. In emission spectroscopy experiments performed using a Hettrick soft x-ray spectrometer,(Back et al., and Cohen et al. APS DPP Meeting 1997.) (hν ~ 300 - 900 eV; λ/Δλ ~ 500), K, Cl, and F emission lines were observed above the continuum of the Al witness plate. Absorption spectroscopy experiments at OMEGA are scheduled to be performed in August 1998.(Cohen et al., this meeting.) We will present results from numerical simulations of these experiments, utilizing non-LTE collisional-radiative, radiation-hydrodynamics, and 3-D view factor codes.

  14. High convergence, indirect drive inertial confinement fusion experiments at Nova

    SciTech Connect

    Lerche, R.A.; Cable, M.D.; Hatchett, S.P.

    1995-06-02

    High convergence, indirect drive implosion experiments have been done at the Nova Laser Facility. The targets were deuterium and deuterium/tritium filled, glass microballoons driven symmetrically by x rays produced in a surrounding uranium hohlraum. Implosions achieved convergence ratios of 24:1 with fuel densities of 19 g/cm{sup 3}; this is equivalent to the range required for the hot spot of ignition scale capsules. The implosions used a shaped drive and were well characterized by a variety of laser and target measurements. The primary measurement was the fuel density using the secondary neutron technique (neutrons from the reaction {sup 2}H({sup 3}H,n){sup 4}He in initially pure deuterium fuel). Laser measurements include power, energy and pointing. Simultaneous measurement of neutron yield, fusion reaction rate, and x-ray images provide additional information about the implosion process. Computer models are in good agreement with measured results.

  15. Estimating site occupancy and abundance using indirect detection indices

    USGS Publications Warehouse

    Stanley, T.R.; Royle, J. Andrew

    2005-01-01

    Knowledge of factors influencing animal distribution and abundance is essential in many areas of ecological research, management, and policy-making. Because common methods for modeling and estimating abundance (e.g., capture-recapture, distance sampling) are sometimes not practical for large areas or elusive species, indices are sometimes used as surrogate measures of abundance. We present an extension of the Royle and Nichols (2003) generalization of the MacKenzie et al. (2002) site-occupancy model that incorporates length of the sampling interval into the, model for detection probability. As a result, we obtain a modeling framework that shows how useful information can be extracted from a class of index methods we call indirect detection indices (IDIs). Examples of IDIs include scent station, tracking tube, snow track, tracking plate, and hair snare surveys. Our model is maximum likelihood, and it can be used to estimate site occupancy and model factors influencing patterns of occupancy and abundance in space. Under certain circumstances, it can also be used to estimate abundance. We evaluated model properties using Monte Carlo simulations and illustrate the method with tracking tube and scent station data. We believe this model will be a useful tool for determining factors that influence animal distribution and abundance.

  16. Fluorescence quenching as an indirect detection method for nitrated explosives.

    PubMed

    Goodpaster, J V; McGuffin, V L

    2001-05-01

    A novel approach based on fluorescence quenching is presented for the analysis of nitrated explosives. Seventeen common explosives and their degradation products are shown to be potent quenchers of pyrene, having Stern-Volmer constants that generally increase with the degree of nitration. Aromatic explosives such as 2,4,6-trinitrotoluene (2,4,6-TNT) are more effective quenchers than aliphatic or nitramine explosives. In addition, nitroaromatic explosives are found to have unique interactions with pyrene that lead to a wavelength dependence of their Stern-Volmer constants. This phenomenon allows for their differentiation from other nitrated explosives. The fluorescence quenching method is then applied to the determination of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine(HMX), 2,4,6-TNT, nitromethane, and ammonium nitrate in various commercial explosive samples. The samples are separated by capillary liquid chromatography with post-column addition of the pyrene solution and detection by laser-induced fluorescence. The indirect fluorescence quenching method shows increased sensitivity and selectivity over traditional UV-visible absorbance as well as the ability to detect a wider range of organic and inorganic nitrated compounds.

  17. Male and Female University Students' Experiences of Indirect Aggression

    ERIC Educational Resources Information Center

    Leenaars, Lindsey; Rinaldi, Christina M.

    2010-01-01

    This study examines the role of sex, gender role orientation, social representations of indirect aggression, and indicators of psychosocial adjustment in indirect aggression and victimization in an emerging adult sample. A total of 42 participants (19 men, 23 women) recruited are required to complete the questionnaires, along with 18 participants…

  18. Direct and indirect detection of higgsino-like WIMPs: Concluding the story of electroweak naturalness

    NASA Astrophysics Data System (ADS)

    Baer, Howard; Barger, Vernon; Mickelson, Dan

    2013-10-01

    Supersymmetric models which fulfill the conditions of electroweak naturalness generally contain light higgsinos with mass not too far from mh≃125 GeV, while other sparticles can be much heavier. In R-parity conserving models, the lightest neutralino is then a higgsino-like WIMP (albeit with non-negligible gaugino components), with thermal relic density well below measured values. This leaves room for axions to function as co-dark matter particles. The local WIMP abundance is then expected to be below standard estimates, and direct and indirect detection rates must be accordingly rescaled. We calculate rescaled direct and indirect higgsino-like WIMP detection rates in SUSY models that fulfill the electroweak naturalness condition. In spite of the rescaling, we find that ton-scale noble liquid detectors can probe the entire higgsino-like WIMP parameter space, so that these experiments should either discover WIMPs or exclude the concept of electroweak naturalness in R-parity conserving natural SUSY models. Prospects for spin-dependent or indirect detection are more limited due in part to the rescaling effect.

  19. Detection of Indirectly-Driven Ion Acoustic Waves

    NASA Astrophysics Data System (ADS)

    Carroll, J. J., III; Drake, R. P.; Smith, T. B.; Montgomery, D. S.; Watt, R. G.; de Groot, J. S.

    1998-11-01

    Recent theory^1 suggests that the non-resonant decay instability and induced scattering (IS) may explain the saturation of ion acoustic waves (IAWs) in laser fusion experiments. IS is found to explain ion wave saturation in lower-density microwave-driven plasmas.^2 We report the results of an experiment at Trident designed to detect ion wave scattering in a high-density laser plasma. The plasma is created from a CH target (6.5 μm thick, 1 mm wide) using a preform beam (175 J, 1.3 ns sq. pulse starting at t=0 ns, 527 nm, line-focus RPP). A pump beam (20 J, 200 ps Gaussian pulse centered at t=+1.7 ns, 527 nm, RPP) drives IAWs with k=2k_0, where k0 is the pump wavenumber. A probe beam (12 J, 1.3 ns sq. pulse starting at t=+1.0 ns, 527 nm, intensity below the SBS threshold) detects strong 2k0 IAWs at 30^o from the original SBS-pump-beam direction but not at 150^o. This is evidence of ion wave scattering. (Work supported by the U.S. DOE and the University of Michigan) ^1B.I. Cohen, B.F. Lasinski, A.B. Langdon and E.A. Williams, Phys. Plasmas 4, 956 (1997). ^2K. Mizuno, F. Kehl and J.S. DeGroot, Phys. Rev. Lett. 56, 2184 (1986).

  20. Capture and indirect detection of inelastic dark matter

    SciTech Connect

    Menon, Arjun; Pierce, Aaron; Morris, Rob; Weiner, Neal

    2010-07-01

    We compute the capture rate for dark matter in the Sun for models where the dominant interaction with nuclei is inelastic--the dark matter up-scatters to a nearby dark ''partner'' state with a small splitting of the order of 100 keV. Such models have been shown to be compatible with DAMA/LIBRA data, as well as data from all other direct detection experiments. The kinematics of inelastic dark matter ensures that the dominant contribution to capture occurs from scattering off of iron. We give a prediction for neutrino rates for current and future neutrino telescopes based on the results from current direct detection experiments. Current bounds from Super-Kamiokande and IceCube-22 significantly constrain these models, assuming annihilations are into two-body standard model final states, such as W{sup +}W{sup -}, tt, bb, or {tau}{sup +{tau}-}. Annihilations into first and second generation quarks and leptons are generally allowed, as are annihilations into new force carriers which decay dominantly into e{sup +}e{sup -}, {mu}{sup +{mu}-}, and {pi}{sup +{pi}-}.

  1. Means and method for capillary zone electrophoresis with laser-induced indirect fluorescence detection

    DOEpatents

    Yeung, Edward S.; Kuhr, Werner G.

    1996-02-20

    A means and method for capillary zone electrphoresis with laser-induced indirect fluorescence detection. A detector is positioned on the capillary tube of a capillary zone electrophoresis system. The detector includes a laser which generates a laser beam which is imposed upon a small portion of the capillary tube. Fluorescence of the elutant electromigrating through the capillary tube is indirectly detected and recorded.

  2. Means and method for capillary zone electrophoresis with laser-induced indirect fluorescence detection

    DOEpatents

    Yeung, Edwards; Kuhr, Werner G.

    1991-04-09

    A means and method for capillary zone electrphoresis with laser-induced indirect fluorescence detection. A detector is positioned on the capillary tube of a capillary zone electrophoresis system. The detector includes a laser which generates a laser beam which is imposed upon a small portion of the capillary tube. Fluorescence of the elutant electromigrating through the capillary tube is indirectly detected and recorded.

  3. New method of antibody detection by indirect immunoperoxidase plaque staining for serodiagnosis of African swine fever.

    PubMed Central

    Pan, I C; Huang, T S; Hess, W R

    1982-01-01

    An indirect immunoperoxidase plaque-staining method was developed for detecting antibody to African swine fever virus infection. In both sensitivity and specificity, the test was comparable to indirect immunofluorescence. Because it has all of the desirable features of the indirect immunofluorescence test and may also be readily used for testing large numbers of sera, the indirect immunoperoxidase plaque-staining method can be used as a single and final serodiagnostic test in a large-scale survey of African swine fever. The indirect immunoperoxidase plaque-staining method should be applicable to other viruses that can be adapted to and grown in cell cultures. Images PMID:6185528

  4. Indirect costs associated with glioblastoma: Experience at one hospital.

    PubMed

    Undabeitia, J; Torres-Bayona, S; Samprón, N; Arrázola, M; Bollar, A; Armendariz, M; Torres, P; Ruiz, I; Caballero, M C; Egaña, L; Querejeta, A; Villanua, J; Pardo, E; Etxegoien, I; Liceaga, G; Urtasun, M; Michan, M; Emparanza, J I; Aldaz, P; Matheu, A; Úrculo, E

    2016-07-20

    Glioblastoma is the most common primary brain tumour. Despite advances in treatment, its prognosis remains dismal, with a mean survival time of about 14 months. Many articles have addressed direct costs, those associated with the diagnosis and treatment of the disease. Indirect costs, those associated with loss of productivity due to the disease, have seldom been described. We conducted a retrospective study in patients diagnosed with glioblastoma at Hospital Universitario Donostia between January 1, 2010 and December 31, 2013. We collected demographics, data regarding the treatment received, and survival times. We calculated the indirect costs with the human capital approach, adjusting the mean salaries of comparable individuals by sex and age and obtaining mortality data for the general population from the Spanish National Statistics Institute. Past salaries were updated to 2015 euros according to the annual inflation rate and we applied a discount of 3.5% compounded yearly to future salaries. We reviewed the records of 99 patients: 46 women (mean age 63.53) and 53 men (mean age 59.94); 29 patients underwent a biopsy and the remaining 70 underwent excisional surgery. Mean survival was 18.092 months for the whole series. The total indirect cost for the series was €11 080 762 (2015). Mean indirect cost per patient was €111 926 (2015). Although glioblastoma is a relatively uncommon type of tumour, accounting for only 4% of all cancers, its poor prognosis and potential sequelae generate disproportionately large morbidity and mortality rates which translate to high indirect costs. Clinicians should be aware of the societal impact of glioblastoma and indirect costs should be taken into account when cost effectiveness studies are performed to better illustrate the overall consequences of this disease. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Indirect chiral separation of tryptophan enantiomers by high performance liquid chromatography with indirect chemiluminiscence detection.

    PubMed

    Zhou, Jie; Chen, Shanshan; Sun, Fang; Luo, Pei; Du, Qiuzheng; Zhao, Suzhen

    2015-12-01

    In recent years, the study of chiral compounds in vivo has received much attention. In this study, a novel method based on high performance liquid chromatography (HPLC) coupled with chemiluminescence (CL) detection was developed for the separation of tryptophan (Trp) enantiomers. o-Phthalaldehyde and N-acetyl-l-cysteine were used as chiral derivatization reagents for Trp before it can be detected by HPLC-CL method. The separation was carried out on an ODS column using a mobile phase composed of methanol-0.01mol/L phosphate buffer (40/60, v/v). Under the optimum conditions, satisfactory results were obtained, including complete separation, good relative standard deviations and low detection limits. The applicability of the proposed method has been validated by determining Trp in biological samples. Linear responses (r>0.9990) were observed over the range of 2.5×10(-7) to 1.2×10(-5)g/mL of Trp enantiomers, with quantitation limit of 2.5×10(-7)g/mL. The assay method shows good specificity to Trp enantiomers, and thus it will have great potential application in clinical diagnosis. The mean extraction efficiency of Trp enantiomers in mice plasma samples were 98.48% and 97.40%, respectively. The mean relative standard deviation (RSD) of Trp enantiomers were <3%.

  6. Towards understanding thermal history of the Universe through direct and indirect detection of dark matter

    NASA Astrophysics Data System (ADS)

    Roszkowski, Leszek; Trojanowski, Sebastian; Turzyński, Krzysztof

    2017-10-01

    We examine the question to what extent prospective detection of dark matter by direct and indirect- detection experiments could shed light on what fraction of dark matter was generated thermally via the freeze-out process in the early Universe. By simulating putative signals that could be seen in the near future and using them to reconstruct WIMP dark matter properties, we show that, in a model- independent approach this could only be achieved in a thin sliver of the parameter space. However, with additional theoretical input the hypothesis about the thermal freeze-out as the dominant mechanism for generating dark matter can potentially be verified. We illustrate this with two examples: an effective field theory of dark matter with a vector messenger and a higgsino or wino dark matter within the MSSM.

  7. [Autoantibody detection by indirect immunofluorescence on HEp-2 cells].

    PubMed

    Sack, U; Conrad, K; Csernok, E; Frank, I; Hiepe, F; Krieger, T; Kromminga, A; Landenberg, P von; Messer, G; Witte, T; Mierau, R

    2009-06-01

    Systemic autoimmune diseases are characterized by the presence of antinuclear autoantibodies (ANA). Diluted patient sera are typically used to screen for the presence of ANA by immunfluorescence microscopy with fixed HEp-2 cells. Despite high-quality test kits, reports of different laboratories frequently present controversial results. This article recommends unified processing and interpretation of HEp-2 based screening for autoantibodies. Suggestions are made for the selection of high-quality test kits, optimized processing and diagnostic procedures. In addition to a relevant clinical diagnosis and an experienced laboratory specialist, the following procedure is highly recommended to achieve good laboratory practice: Initial HEp-2 based screening by indirect immunofluorescence, starting with a 1:80 serum dilution, and evaluation in a bright fluorescence microscope, pathological values from a titer of 1:160 upwards, internal quality checks and unified interpretation. We aim to improve diagnosis and care of patients with autoimmune diseases as a central focus of the European Autoimmunity Standardization Initiative (EASI).

  8. Indirect dark matter detection for flattened dwarf galaxies

    NASA Astrophysics Data System (ADS)

    Sanders, Jason L.; Evans, N. Wyn; Geringer-Sameth, Alex; Dehnen, Walter

    2016-09-01

    Gamma-ray experiments seeking to detect evidence of dark matter annihilation in dwarf spheroidal galaxies require knowledge of the distribution of dark matter within these systems. We analyze the effects of flattening on the annihilation (J) and decay (D) factors of dwarf spheroidal galaxies with both analytic and numerical methods. Flattening has two consequences: first, there is a geometric effect as the squeezing (or stretching) of the dark matter distribution enhances (or diminishes) the J-factor; second, the line of sight velocity dispersion of stars must hold up the flattened baryonic component in the flattened dark matter halo. We provide analytic formulas and a simple numerical approach to estimate the correction to the J- and D-factors required over simple spherical modeling. The formulas are validated with a series of equilibrium models of flattened stellar distributions embedded in flattened dark-matter distributions. We compute corrections to the J- and D-factors for the Milky Way dwarf spheroidal galaxies under the assumption that they are all prolate or all oblate and find that the hierarchy of J-factors for the dwarf spheroidals is slightly altered (typical correction factors for an ellipticity of 0.4 are 0.75 for the oblate case and 1.6 for the prolate case). We demonstrate that spherical estimates of the D-factors are very insensitive to the flattening and introduce uncertainties significantly less than the uncertainties in the D-factors from the other observables for all the dwarf spheroidals (for example, +10 per cent/-3 per cent for a typical ellipticity of 0.4). We conclude by investigating the spread in correction factors produced by triaxial figures and provide uncertainties in the J-factors for the dwarf spheroidals using different physically motivated assumptions for their intrinsic shape and axis alignments. We find that the uncertainty in the J-factors due to triaxiality increases with the observed ellipticity and, in general, introduces

  9. A rapid method to improve protein detection by indirect ELISA

    USDA-ARS?s Scientific Manuscript database

    The enzyme-linked immunosorbant assay (ELISA) is a rapid, high-throughput, quantitative immunoassay for the selective detection of target antigens. The general principle behind an ELISA is antibody mediated capture and detection of an antigen with a measureable substrate. Numerous incarnations of th...

  10. Predicting and detecting reciprocity between indirect ecological interactions and evolution.

    PubMed

    Estes, James A; Brashares, Justin S; Power, Mary E

    2013-05-01

    Living nature can be thought of as a tapestry, defined not only by its constituent parts but also by how these parts are woven together. The weaving of this tapestry is a metaphor for species interactions, which can be divided into three broad classes: competitive, mutualistic, and consumptive. Direct interactions link together as more complex networks, for example, the joining of consumptive interactions into food webs. Food web dynamics are driven, in turn, by changes in the abundances of web members, whose numbers or biomass respond to bottom-up (resource limitation) and top-down (consumer limitation) forcing. The relative strengths of top-down and bottom-up forcing on the abundance of a given web member depend on its ecological context, including its topological position within the food web. Top-down effects by diverse consumers are nearly ubiquitous, in many cases influencing the structure and operation of ecosystems. While the ecological effects of such interactions are well known, far less is known of their evolutionary consequences. In this essay, we describe sundry consequences of these interaction chains on species and ecosystem processes, explain several known or suspected evolutionary effects of consumer-induced interaction chains, and identify areas where reciprocity between ecology and evolution involving the indirect effects of consumer-prey interaction chains might be further explored.

  11. The Early Years of Indirect Drive Development for High Energy Density Physics Experiments at AWE

    NASA Astrophysics Data System (ADS)

    Thomas, Brian

    2016-10-01

    The importance of laser driven indirect drive for high energy density physics experiments was recognised at A WE in 1971. The two beam 1TW HELEN laser was procured to work in this area and experiments with this system began in 1980. Early experiments in hohlraum coupling and performance scaling with both l.06μm and 0.53μm will be described together with experiments specifically designed to confirm the understanding of radiation wave propagation, hohlraum heating and hohlraum plasma filling. The use of indirect drive for early experiments to study spherical and cylindrical implosions, opacity, EOS, mix and planar radiation hydrodynamics experiments will also be described.

  12. Indirect Charged Particle Detection: Concepts and a Classroom Demonstration

    ERIC Educational Resources Information Center

    Childs, Nicholas B.; Horányi, Mihály; Collette, Andrew

    2013-01-01

    We describe the principles of macroscopic charged particle detection in the laboratory and their connections to concepts taught in the physics classroom. Electrostatic dust accelerator systems, capable of launching charged dust grains at hypervelocities (1-100 km/s), are a critical tool for space exploration. Dust grains in space typically have…

  13. Indirect Charged Particle Detection: Concepts and a Classroom Demonstration

    ERIC Educational Resources Information Center

    Childs, Nicholas B.; Horányi, Mihály; Collette, Andrew

    2013-01-01

    We describe the principles of macroscopic charged particle detection in the laboratory and their connections to concepts taught in the physics classroom. Electrostatic dust accelerator systems, capable of launching charged dust grains at hypervelocities (1-100 km/s), are a critical tool for space exploration. Dust grains in space typically have…

  14. Indirect detection of light neutralino dark matter in the next-to-minimal supersymmetric standard model

    SciTech Connect

    Ferrer, Francesc; Krauss, Lawrence M.; Profumo, Stefano

    2006-12-01

    We explore the prospects for indirect detection of neutralino dark matter in supersymmetric models with an extended Higgs sector (next-to-minimal supersymmetric standard model, or NMSSM). We compute, for the first time, one-loop amplitudes for NMSSM neutralino pair annihilation into two photons and two gluons, and point out that extra diagrams (with respect to the minimal supersymmetric standard model, or MSSM), featuring a potentially light CP-odd Higgs boson exchange, can strongly enhance these radiative modes. Expected signals in neutrino telescopes due to the annihilation of relic neutralinos in the Sun and in the Earth are evaluated, as well as the prospects of detection of a neutralino annihilation signal in space-based gamma-ray, antiproton and positron search experiments, and at low-energy antideuteron searches. We find that in the low mass regime the signals from capture in the Earth are enhanced compared to the MSSM, and that NMSSM neutralinos have a remote possibility of affecting solar dynamics. Also, antimatter experiments are an excellent probe of galactic NMSSM dark matter. We also find enhanced two-photon decay modes that make the possibility of the detection of a monochromatic gamma-ray line within the NMSSM more promising than in the MSSM, although likely below the sensitivity of next generation gamma-ray telescopes.

  15. Indirectly detected chemical shift correlation NMR spectroscopy in solids under fast magic angle spinning

    SciTech Connect

    Mao, Kanmi

    2011-01-01

    The development of fast magic angle spinning (MAS) opened up an opportunity for the indirect detection of insensitive low-γ nuclei (e.g., 13C and 15N) via the sensitive high-{gamma} nuclei (e.g., 1H and 19F) in solid-state NMR, with advanced sensitivity and resolution. In this thesis, new methodology utilizing fast MAS is presented, including through-bond indirectly detected heteronuclear correlation (HETCOR) spectroscopy, which is assisted by multiple RF pulse sequences for 1H-1H homonuclear decoupling. Also presented is a simple new strategy for optimization of 1H-1H homonuclear decoupling. As applications, various classes of materials, such as catalytic nanoscale materials, biomolecules, and organic complexes, are studied by combining indirect detection and other one-dimensional (1D) and two-dimensional (2D) NMR techniques. Indirectly detected through-bond HETCOR spectroscopy utilizing refocused INEPT (INEPTR) mixing was developed under fast MAS (Chapter 2). The time performance of this approach in 1H detected 2D 1H{l_brace}13C{r_brace} spectra was significantly improved, by a factor of almost 10, compared to the traditional 13C detected experiments, as demonstrated by measuring naturally abundant organic-inorganic mesoporous hybrid materials. The through-bond scheme was demonstrated as a new analytical tool, which provides complementary structural information in solid-state systems in addition to through-space correlation. To further benefit the sensitivity of the INEPT transfer in rigid solids, the combined rotation and multiple-pulse spectroscopy (CRAMPS) was implemented for homonuclear 1H decoupling under fast MAS (Chapter 3). Several decoupling schemes (PMLG5m$\\bar{x}$, PMLG5mm$\\bar{x}$x and SAM3) were analyzed to maximize the performance of through-bond transfer based

  16. The relative weights of direct and indirect experiences in the formation of environmental risk beliefs.

    PubMed

    Viscusi, W Kip; Zeckhauser, Richard J

    2015-02-01

    Direct experiences, we find, influence environmental risk beliefs more than the indirect experiences derived from outcomes to others. This disparity could have a rational basis. Or it could be based on behavioral proclivities in accord with the well-established availability heuristic or the vested-interest heuristic, which we introduce in this article. Using original data from a large, nationally representative sample, this article examines the perception of, and responses to, morbidity risks from tap water. Direct experiences have a stronger and more consistent effect on different measures of risk belief. Direct experiences also boost the precautionary response of drinking bottled water and drinking filtered water, while indirect experiences do not. These results are consistent with the hypothesized neglect of indirect experiences in other risk contexts, such as climate change.

  17. Indirect photometric detection of boron cluster anions electrophoretically separated in methanol.

    PubMed

    Vítová, Lada; Fojt, Lukáš; Vespalec, Radim

    2014-04-18

    3,5-Dinitrobenzoate and picrate are light absorbing anions pertinent to indirect photometric detection of boron cluster anions in buffered methanolic background electrolytes (BGEs). Tris(hydroxymethyl)aminomethane and morpholine have been used as buffering bases, which eliminated baseline steps, and minimized the baseline noise. In methanolic BGEs, mobilities of boron cluster anions depend on both ionic constituents of the BGE buffer. This dependence can be explained by ion pair interaction of detected anions with BGE cations, which are not bonded into ion pairs with the BGE anions. The former ion pair interaction decreases sensitivity of the indirect photometric detection.

  18. Indirect fluorometric detection of anions in thin-layer chromatography

    SciTech Connect

    Ma, Y.; Yeung, E.S.

    1988-04-01

    Thin-layer chromatography (TLC) is a broadly applicable separation technique. There is a technique for TLC quantitation known as fluorescence quenching. In fact, commercial TLC plates are available with a fluorophor already incorporated for this purpose. It is really a misnomer because rarely does the analyte actually change the fluorescence quantum yield of the fluorophor. In reality that is only a modified absorption technique. The analyte absorbs the excitation light (or the emitted light), and depletes the amount of fluorescence. The advantage is the elimination of UV optics in the observation of emission, so that direct visualization is possible for UV chromophors. Sensitivity is at best comparable to UV transmission or UV reflectance spectrometry. In this article, they describe the detection of nonfluorescing and nonabsorbing anions. Displacement of a fluorescing (background) eluting ion by the analyte ion due to electroneutrality gives rise to the response.

  19. A microfluidic indirect competitive immunoassay for multiple and sensitive detection of testosterone in serum and urine.

    PubMed

    Wang, Huashan; Li, Juanjuan; Zhang, Xiaoqing; Hu, Binfeng; Liu, Yang; Zhang, Lin; Cha, Ruitao; Sun, Jiashu; Jiang, Xingyu

    2016-02-07

    We demonstrate a microfluidic-based indirect competitive chemiluminescence enzyme immunoassay (MIC) for multiple, sensitive, reliable and rapid detection of testosterone in human serum and urine samples. As MIC can detect biomarkers in a cost-effective and easy-to-operate manner, it may have great potential for clinical diagnosis and point-of-care testing (POCT).

  20. Hoping to indirectly detect Dark Matter with cosmic rays

    NASA Astrophysics Data System (ADS)

    Cirelli, Marco

    2010-11-01

    Dark Matter constitutes more that 80% of the total amount of matter in the Universe, yet almost nothing is known about its nature. A powerful investigation technique is that of searching for the products of annihilations of Dark Matter particles in the galactic halo, on top of the ordinary cosmic rays. Recent data from the PAMELA and FERMI satellites and a number of balloon experiment have reported unexpected excesses in the measured fluxes of cosmic rays. Are these the first direct evidences for Dark Matter? If yes, which DM models and candidates can explain these anomalies (in terms of annihilations) and what do they imply for future searches? What are the constraints from gamma rays measurements and cosmology? [Report number: Saclay T-10/098, CERN-PH-TH/2010-183].

  1. The WIMP Forest: Indirect Detection of a Chiral Square

    SciTech Connect

    Bertone, Gianfranco; Jackson, C.B.; Shaughnessy, Gabe; Tait, Tim M.P.; Vallinotto, Alberto

    2009-04-01

    The spectrum of photons arising from WIMP annihilation carries a detailed imprint of the structure of the dark sector. In particular, loop-level annihilations into a photon and another boson can in principle lead to a series of lines (a WIMP forest) at energies up to the WIMP mass. A specific model which illustrates this feature nicely is a theory of two universal extra dimensions compactified on a chiral square. Aside from the continuum emission, which is a generic prediction of most dark matter candidates, we find a 'forest' of prominent annihilation lines that, after convolution with the angular resolution of current experiments, leads to a distinctive (2-bump plus continuum) spectrum, which may be visible in the near future with the Fermi Gamma-Ray Space Telescope (formerly known as GLAST).

  2. Indirect detection of subsurface outflow from a rift valley lake

    NASA Astrophysics Data System (ADS)

    Darling, W. G.; Allen, D. J.; Armannsson, H.

    1990-02-01

    Naivasha, highest of the Kenya (Gregory) Rift Valley lakes, has no surface outlet. However, unlike other Rift lakes it has not become saline despite high potential evaporation rates, which indicates that there must be some subsurface drainage. The fate of this outflow has been the subject of speculation for many years, especially during the general decline in lake water level during the 1980's. Particularly to the south of the lake, there are few opportunities to obtain information from direct groundwater sampling. However, the stable isotopic composition of fumarole steam from late Quaternary volcanic centres in the area has been used to infer groundwater composition. Using a simple mixing model between Rift-flank groundwater and highly-evaporated lakewater, this has enabled subsurface water flow to be contoured by its lakewater content. By this method, outflow can still be detected some 30 km to the south of the lake. Stable isotope data also confirm that much of the steam used by the local Olkaria geothermal power station is derived from lakewater, though simple balance considerations show that steam use cannot alone be responsible for the fall in lake level observed during the 1980's.

  3. Calculations for Indirectly Driven Be capsule Implosion Experiments at Omega

    NASA Astrophysics Data System (ADS)

    Kyrala, George; Kline, John; Merritt, Elizabeth

    2014-10-01

    Beryllium (Be) ablators offer an attractive path to ignition on the National Ignition Facility (NIF). They offer better ablation rate, higher efficiency, and higher ablation velocity than the currently used CH or Diamond capsules. We have designed a capsule of Be for implosions at Omega to test our understanding of Be implosions in the foot of the anticipated NIF pulse, ~100-110 eV for a period of 1-2 ns drive. We calculated the emission profile, diameter, and implosion time. We will present a comparison to the completed experiments using either Be or CH ablator. We also will provide calculations of the effect of adding different amounts of an Argon dopant on the expected x-ray yield and emission shapes. This work is supported by the US DOE.

  4. Detection of antinuclear antibodies by indirect immunofluorescence and by solid phase assay.

    PubMed

    Op De Beeck, Katrijn; Vermeersch, Pieter; Verschueren, Patrick; Westhovens, René; Mariën, Godelieve; Blockmans, Daniel; Bossuyt, Xavier

    2011-10-01

    Testing for antinuclear antibodies is useful for the diagnosis of systemic rheumatic diseases. Solid phase assays are increasingly replacing indirect immunofluorescence for detection of antinuclear antibodies. In the most recent generation of solid phase assays, manufacturers attempt to improve the performance of the assays by adding extra antigens. Solid phase assay (EliA CTD Screen, Phadia, in which antibodies to 17 antigens are detected) was compared to indirect immunofluorescence for the detection of antinuclear antibodies in diagnostic samples of 236 patients with autoimmune connective tissue diseases, in 149 healthy blood donors, 139 patients with chronic fatigue syndrome, and 134 diseased controls. The sensitivity of EliA CTD Screen for systemic lupus erythematosus, systemic sclerosis, primary Sjögren's syndrome, mixed connective tissue disease, and inflammatory myopathy was 74%, 72%, 89%, 100%, and 39%, respectively. The reactivity in blood donors, in patients with chronic fatigue syndrome, and in diseased controls was <4%. Likelihood ratios increased with increasing antibody concentrations. Generally, a positive test result by EliA CTD Screen had a higher likelihood ratio for systemic rheumatic disease than a positive test result by indirect immunofluorescence. A negative test result by indirect immunofluorescence, however, had a lower likelihood ratio than a negative test result by EliA CTD Screen, indicating that the negative predictive value was higher for indirect immunofluorescence than for EliA CTD screen.

  5. Capillary zone electrophoresis with indirect photometric detection in the visible range.

    PubMed

    Malá, Z; Vespalec, R; Bocek, P

    1994-12-01

    Sensitivity and applicability of commonly used indirect photometric detection in the UV region can be adversely affected by the absorption of the UV light by detected solutes and/or by matrix constituents migrating with them. If the visible light is exploited instead of the UV light, both these disadvantages may be for the most part eliminated, and, moreover, the indirect photometric detection will extend its versatility and sensitivity. Prospects as well as main problems of the approach were tested using inorganic ions as analytes. If organic dyes with a molar light absorption coefficient of the order of 10(6) mol-1 L m-1 was selected as the light-absorbing constituents of the background electrolyte, detection sensitivity comparable with the best reported results was reached for anions; for cations, the detection limit was even lower by two orders of magnitude.

  6. Indirect detection of infinite-speed MAS solid-state NMR spectra

    NASA Astrophysics Data System (ADS)

    Perras, Frédéric A.; Venkatesh, Amrit; Hanrahan, Michael P.; Goh, Tian Wei; Huang, Wenyu; Rossini, Aaron J.; Pruski, Marek

    2017-03-01

    Heavy spin-1/2 nuclides are known to possess very large chemical shift anisotropies that can challenge even the most advanced magic-angle-spinning (MAS) techniques. Wide manifolds of overlapping spinning sidebands and insufficient excitation bandwidths often obfuscate meaningful spectral information and force the use of static, low-resolution solid-state (SS)NMR methods for the characterization of materials. To address these issues, we have merged fast-magic-angle-turning (MAT) and dipolar heteronuclear multiple-quantum coherence (D-HMQC) experiments to obtain D-HMQC-MAT pulse sequences which enable the rapid acquisition of 2D SSNMR spectra that correlate isotropic 1H chemical shifts to the indirectly detected isotropic ;infinite-MAS; spectra of heavy spin-1/2 nuclides. For these nuclides, the combination of fast MAS and 1H detection provides a high sensitivity, which rivals the DNP-enhanced ultra-wideline SSNMR. The new pulse sequences were used to determine the Pt coordination environments in a complex mixture of decomposition products of transplatin and in a metal-organic framework with Pt ions coordinated to the linker ligands.

  7. Swelling behavior detection of irradiated U-10Zr alloy fuel using indirect neutron radiography

    NASA Astrophysics Data System (ADS)

    Sun, Yong; Huo, He-yong; Wu, Yang; Li, Jiangbo; Zhou, Wei; Guo, Hai-bing; Li, Hang; Cao, Chao; Yin, Wei; Wang, Sheng; Liu, Bin; Feng, Qi-jie; Tang, Bin

    2016-11-01

    It is hopeful that fusion-fission hybrid energy system will become an effective approach to achieve long-term sustainable development of fission energy. U-10Zr alloy (which means the mass ratio of Zr is 10%) fuel is the key material of subcritical blanket for fusion-fission hybrid energy system which the irradiation performance need to be considered. Indirect neutron radiography is used to detect the irradiated U-10Zr alloy because of the high residual dose in this paper. Different burnup samples (0.1%, 0.3%, 0.5% and 0.7%) have been tested with a special indirect neutron radiography device at CMRR (China Mianyang Research Reactor). The resolution of the device is better than 50 μm and the quantitative analysis of swelling behaviors was carried out. The results show that the swelling behaviors relate well to burnup character which can be detected accurately by indirect neutron radiography.

  8. PRECONCENTRATION OF ALIPHATIC AMINES FROM WATER DETERMINED BY CAPILLARY ELECTROPHORESIS WITH INDIRECT UV DETECTION

    EPA Science Inventory

    Preconcentration methodology based on adsorption chromatographies for enriching aliphatic amines (c1 to C4 substituted primary, secondary, and tertiary) and alkanolamines in water was studied by free zone capillary electrophoresis (CZE)with indirect UV detection. The solid-phase ...

  9. Using Indirect Questions to Detect Intimate Partner Violence: The SAFE-T Questionnaire

    ERIC Educational Resources Information Center

    Fulfer, Jamie L.; Tyler, Jillian J.; Choi, Natalie J. S.; Young, Jill A.; Verhulst, Steven J.; Kovach, Regina; Dorsey, J. Kevin

    2007-01-01

    A screening instrument for detecting intimate partner violence (IPV) was developed using indirect questions. The authors identified 5 of 18 items studied that clearly distinguished victims of IPV from a random group of health conference attendees with a sensitivity of 85% and a specificity of 87%. This 5-item instrument (SAFE-T) was then tested on…

  10. PRECONCENTRATION OF ALIPHATIC AMINES FROM WATER DETERMINED BY CAPILLARY ELECTROPHORESIS WITH INDIRECT UV DETECTION

    EPA Science Inventory

    Preconcentration methodology based on adsorption chromatographies for enriching aliphatic amines (c1 to C4 substituted primary, secondary, and tertiary) and alkanolamines in water was studied by free zone capillary electrophoresis (CZE)with indirect UV detection. The solid-phase ...

  11. Powering up with indirect reciprocity in a large-scale field experiment

    PubMed Central

    Yoeli, Erez; Hoffman, Moshe; Rand, David G.; Nowak, Martin A.

    2013-01-01

    A defining aspect of human cooperation is the use of sophisticated indirect reciprocity. We observe others, talk about others, and act accordingly. We help those who help others, and we cooperate expecting that others will cooperate in return. Indirect reciprocity is based on reputation, which spreads by communication. A crucial aspect of indirect reciprocity is observability: reputation effects can support cooperation as long as peoples’ actions can be observed by others. In evolutionary models of indirect reciprocity, natural selection favors cooperation when observability is sufficiently high. Complimenting this theoretical work are experiments where observability promotes cooperation among small groups playing games in the laboratory. Until now, however, there has been little evidence of observability’s power to promote large-scale cooperation in real world settings. Here we provide such evidence using a field study involving 2413 subjects. We collaborated with a utility company to study participation in a program designed to prevent blackouts. We show that observability triples participation in this public goods game. The effect is over four times larger than offering a $25 monetary incentive, the company’s previous policy. Furthermore, as predicted by indirect reciprocity, we provide evidence that reputational concerns are driving our observability effect. In sum, we show how indirect reciprocity can be harnessed to increase cooperation in a relevant, real-world public goods game. PMID:23754399

  12. Powering up with indirect reciprocity in a large-scale field experiment.

    PubMed

    Yoeli, Erez; Hoffman, Moshe; Rand, David G; Nowak, Martin A

    2013-06-18

    A defining aspect of human cooperation is the use of sophisticated indirect reciprocity. We observe others, talk about others, and act accordingly. We help those who help others, and we cooperate expecting that others will cooperate in return. Indirect reciprocity is based on reputation, which spreads by communication. A crucial aspect of indirect reciprocity is observability: reputation effects can support cooperation as long as peoples' actions can be observed by others. In evolutionary models of indirect reciprocity, natural selection favors cooperation when observability is sufficiently high. Complimenting this theoretical work are experiments where observability promotes cooperation among small groups playing games in the laboratory. Until now, however, there has been little evidence of observability's power to promote large-scale cooperation in real world settings. Here we provide such evidence using a field study involving 2413 subjects. We collaborated with a utility company to study participation in a program designed to prevent blackouts. We show that observability triples participation in this public goods game. The effect is over four times larger than offering a $25 monetary incentive, the company's previous policy. Furthermore, as predicted by indirect reciprocity, we provide evidence that reputational concerns are driving our observability effect. In sum, we show how indirect reciprocity can be harnessed to increase cooperation in a relevant, real-world public goods game.

  13. Unconscious deception detection measured by finger skin temperature and indirect veracity judgments-results of a registered report.

    PubMed

    van 't Veer, Anna E; Gallucci, Marcello; Stel, Mariëlle; van Beest, Ilja

    2015-01-01

    A pre-registered experiment was conducted to examine psychophysiological responses to being lied to. Bridging research on social cognition and deception detection, we hypothesized that observing a liar compared to a truth-teller would decrease finger skin temperature of observers. Participants first watched two targets while not forewarned that they would later be asked to judge (direct and indirect) veracity, and then watched another two targets while forewarned about this. During both these phases finger skin temperature was measured. Findings pertaining to temperature partly confirmed our main hypothesis. When participants were observing a liar, irrespective of being forewarned, on average finger skin temperature declined over time. In the forewarned phase, temperature trajectories of truth-tellers were higher than those of liars, however, in the not forewarned phase, this pattern was reversed. Results confirmed our further hypotheses that participants judge liars as less likeable and less trustworthy than truth-tellers-an indication of indirect deception detection. Our hypothesis that the effect size for trustworthiness would be bigger than that of liking was not supported by the data. Additionally, and also confirming our hypothesis, participants performed around chance level when directly judging whether the target person was lying. Exploratory analyses are reported with regard to truth bias and dependency between direct and indirect veracity judgments. Limitations and directions for future work related to the existence of psychophysiological indicators of deception detection are discussed.

  14. Unconscious deception detection measured by finger skin temperature and indirect veracity judgments—results of a registered report

    PubMed Central

    van ’t Veer, Anna E.; Gallucci, Marcello; Stel, Mariëlle; van Beest, Ilja

    2015-01-01

    A pre-registered experiment was conducted to examine psychophysiological responses to being lied to. Bridging research on social cognition and deception detection, we hypothesized that observing a liar compared to a truth-teller would decrease finger skin temperature of observers. Participants first watched two targets while not forewarned that they would later be asked to judge (direct and indirect) veracity, and then watched another two targets while forewarned about this. During both these phases finger skin temperature was measured. Findings pertaining to temperature partly confirmed our main hypothesis. When participants were observing a liar, irrespective of being forewarned, on average finger skin temperature declined over time. In the forewarned phase, temperature trajectories of truth-tellers were higher than those of liars, however, in the not forewarned phase, this pattern was reversed. Results confirmed our further hypotheses that participants judge liars as less likeable and less trustworthy than truth-tellers—an indication of indirect deception detection. Our hypothesis that the effect size for trustworthiness would be bigger than that of liking was not supported by the data. Additionally, and also confirming our hypothesis, participants performed around chance level when directly judging whether the target person was lying. Exploratory analyses are reported with regard to truth bias and dependency between direct and indirect veracity judgments. Limitations and directions for future work related to the existence of psychophysiological indicators of deception detection are discussed. PMID:26106339

  15. An indirect ELISA and a PCR technique for the detection of Grouper (Epinephelus marginatus) mislabeling.

    PubMed

    Asensio, Luis; González, Isabel; Pavón, Miguel A; García, Teresa; Martín, Rosario

    2008-06-01

    An indirect enzyme-linked immunosorbent assay (ELISA) and a multiplex polymerase chain reaction (PCR) procedure was applied for the detection of Grouper (Epinephelus marginatus) mislabelling in the fish market. An indirect ELISA (microtiter-plate format) using two monoclonal antibodies (3D12 and 1A4) was assayed and multiplex PCR performed using species-specific primers of the 5S rDNA gene for the rapid authentication of grouper. A total of 70 commercial fish fillet samples, collected from local markets and supermarkets, labelled as grouper were analysed: 12 of the 70 samples were confirmed to be Grouper. The PCR technique permitted the detection of Nile Perch (Lates niloticus) in the commercial fillet samples, which was not possible using ELISA. The results suggest that both ELISA and PCR are specific and reliable tools for the detection of Grouper mislabelling/adulteration and the accurate implementation of traceability for successful regulatory food controls.

  16. Doppler effect on indirect detection of dark matter using dark matter only simulations

    NASA Astrophysics Data System (ADS)

    Powell, Devon; Laha, Ranjan; Ng, Kenny C. Y.; Abel, Tom

    2017-03-01

    Indirect detection of dark matter is a major avenue for discovery. However, baryonic backgrounds are diverse enough to mimic many possible signatures of dark matter. In this work, we study the newly proposed technique of dark matter velocity spectroscopy [E. G. Speckhard, K. C. Y. Ng, J. F. Beacom, and R. Laha, Phys. Rev. Lett. 116, 031301 (2016), 10.1103/PhysRevLett.116.031301]. The nonrotating dark matter halo and the Solar motion produce a distinct longitudinal dependence of the signal which is opposite in direction to that produced by baryons. Using collisionless dark matter only simulations of Milky Way like halos, we show that this new signature is robust and holds great promise. We develop mock observations by a high energy resolution x-ray spectrometer on a sounding rocket, the Micro-X experiment, to our test case, the 3.5 keV line. We show that by using six different pointings, Micro-X can exclude a constant line energy over various longitudes at ≥3 σ . The halo triaxiality is an important effect, and it will typically reduce the significance of this signal. We emphasize that this new smoking gun in motion signature of dark matter is general and is applicable to any dark matter candidate which produces a sharp photon feature in annihilation or decay.

  17. Doppler effect on indirect detection of dark matter using dark matter only simulations

    DOE PAGES

    Powell, Devon; Laha, Ranjan; Ng, Kenny C. Y.; ...

    2017-03-15

    Indirect detection of dark matter is a major avenue for discovery. However, baryonic backgrounds are diverse enough to mimic many possible signatures of dark matter. In this work, we study the newly proposed technique of dark matter velocity spectroscopy. The nonrotating dark matter halo and the Solar motion produce a distinct longitudinal dependence of the signal which is opposite in direction to that produced by baryons. Using collisionless dark matter only simulations of Milky Way like halos, we show that this new signature is robust and holds great promise. We develop mock observations by a high energy resolution x-ray spectrometermore » on a sounding rocket, the Micro-X experiment, to our test case, the 3.5 keV line. We show that by using six different pointings, Micro-X can exclude a constant line energy over various longitudes at ≥ 3σ. As a result, the halo triaxiality is an important effect, and it will typically reduce the significance of this signal. We emphasize that this new smoking gun in motion signature of dark matter is general and is applicable to any dark matter candidate which produces a sharp photon feature in annihilation or decay.« less

  18. Detection of direct and indirect noise generated by synthetic hot spots in a duct

    NASA Astrophysics Data System (ADS)

    De Domenico, Francesca; Rolland, Erwan O.; Hochgreb, Simone

    2017-04-01

    Sound waves in a combustor are generated from fluctuations in the heat release rate (direct noise) or the acceleration of entropy, vorticity or compositional perturbations through nozzles or turbine guide vanes (indirect or entropy noise). These sound waves are transmitted downstream as well as reflected upstream of the acceleration point, contributing to the overall noise emissions, or triggering combustion instabilities. Previous experiments attempted to isolate indirect noise by generating thermoacoustic hot spots electrically and measuring the transmitted acoustic waves, yet there are no measurements on the backward propagating entropy and acoustic waves. This work presents the first measurements which clearly separate the direct and indirect noise contributions to pressure fluctuations upstream of the acceleration point. Synthetic entropy spots are produced by unsteady electrical heating of a grid of thin wires located in a tube. Compression waves (direct noise) are generated from this heating process. The hot spots are then advected with the mean flow and finally accelerated through an orifice plate located at the end of the tube, producing a strong acoustic signature which propagates upstream (indirect noise). The convective time is selected to be longer than the heating pulse length, in order to obtain a clear time separation between direct and indirect noise in the overall pressure trace. The contribution of indirect noise to the overall noise is shown to be non-negligible either in subsonic or sonic throat conditions. However, the absolute amplitude of direct noise is larger than the corresponding fraction of indirect noise, explaining the difficulty in clearly identifying the two contributions when they are merged. Further, the work shows the importance of using appropriate pressure transducer instrumentation and correcting for the respective transfer functions in order to account for low frequency effects in the determination of pressure fluctuations.

  19. Quantitative aspects of rare earth metal determinations using capillary electrophoresis with indirect absorbance detection

    SciTech Connect

    Colburn, B.A.; Starnes, S.D.; Sepaniak, M.J.

    1995-04-01

    The practical utility of capillary zone electrophoresis with indirect absorbance detection is examined for the separation and quantitation of rare earth metals. Various imidazole derivatives are investigated as to their suitability as running buffer (displaceable) detection ions with {alpha}-hydroxyisobutyric acid functioning as a chelating agent to enhance separations. Parameters important for quantitative analysis, such as limits of detection, relative standard deviation of peak areas, efficiency, resolution, peak shape and linear dynamic range are presented. The influence of sample matrix, method of injection, and background ion identity on these parameters are investigated and discussed.

  20. Combined Direct and Indirect CT Venography (Combined CTV) in Detecting Lower Extremity Deep Vein Thrombosis

    PubMed Central

    Shi, Wan-Yin; Wang, Li-Wei; Wang, Shao-Juan; Yin, Xin-Dao; Gu, Jian-Ping

    2016-01-01

    Abstract This study aimed to evaluate the diagnostic accuracy of combined direct and indirect CT venography (combined CTV) in the detection of lower extremity deep vein thrombosis (LEDVT). The institutional review board approved the study protocol, and patients or qualifying family members provided informed consent. A total of 96 consecutive patients undergoing combined CTV were prospectively enrolled. A combined examination with digital subtraction angiography (DSA) plus duplex ultrasonography (US) was used as the criterion standard. Three observers were blinded to clinical, DSA, and US results, and they independently analyzed all combined CTV datasets. Interobserver agreement was expressed in terms of the Cohen k value for categorical variables. Accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of combined CTV in the detection of LEDVT were determined by using patient- and location-based evaluations. Of the 96 patients, DSA plus US revealed LEDVT in 125 segmental veins in 63 patients. Patient-based evaluation with combined CTV yielded an accuracy of 96.9% to 97.9%, a sensitivity of 95.2% to 96.8%, a specificity of 100% to 100%, a PPV of 100% to 100%, and an NPV of 91.7% to 94.3% in the detection of LEDVT. Location-based evaluation yielded similar results. Through combined direct and indirect CTV, patients obtained a combined CT angiogram on the diseased limb and an indirect CT angiogram on the opposite side. The image quality of combined CTV was superior to an indirect venogram. Combined CTV shows promising diagnostic accuracy in the detection of LEDVT with 3-dimensional modeling of the lower limb venous system. PMID:26986113

  1. Combined Direct and Indirect CT Venography (Combined CTV) in Detecting Lower Extremity Deep Vein Thrombosis.

    PubMed

    Shi, Wan-Yin; Wang, Li-Wei; Wang, Shao-Juan; Yin, Xin-Dao; Gu, Jian-Ping

    2016-03-01

    This study aimed to evaluate the diagnostic accuracy of combined direct and indirect CT venography (combined CTV) in the detection of lower extremity deep vein thrombosis (LEDVT). The institutional review board approved the study protocol, and patients or qualifying family members provided informed consent. A total of 96 consecutive patients undergoing combined CTV were prospectively enrolled. A combined examination with digital subtraction angiography (DSA) plus duplex ultrasonography (US) was used as the criterion standard. Three observers were blinded to clinical, DSA, and US results, and they independently analyzed all combined CTV datasets. Interobserver agreement was expressed in terms of the Cohen k value for categorical variables. Accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of combined CTV in the detection of LEDVT were determined by using patient- and location-based evaluations. Of the 96 patients, DSA plus US revealed LEDVT in 125 segmental veins in 63 patients. Patient-based evaluation with combined CTV yielded an accuracy of 96.9% to 97.9%, a sensitivity of 95.2% to 96.8%, a specificity of 100% to 100%, a PPV of 100% to 100%, and an NPV of 91.7% to 94.3% in the detection of LEDVT. Location-based evaluation yielded similar results. Through combined direct and indirect CTV, patients obtained a combined CT angiogram on the diseased limb and an indirect CT angiogram on the opposite side. The image quality of combined CTV was superior to an indirect venogram. Combined CTV shows promising diagnostic accuracy in the detection of LEDVT with 3-dimensional modeling of the lower limb venous system.

  2. Comparison of various NMR methods for the indirect detection of nitrogen-14 nuclei via protons in solids

    NASA Astrophysics Data System (ADS)

    Shen, Ming; Trébosc, Julien; O'Dell, Luke A.; Lafon, Olivier; Pourpoint, Frédérique; Hu, Bingwen; Chen, Qun; Amoureux, Jean-Paul

    2015-09-01

    We present an experimental comparison of several through-space Hetero-nuclear Multiple-Quantum Correlation experiments, which allow the indirect observation of homo-nuclear single- (SQ) or double-quantum (DQ) 14N coherences via spy 1H nuclei. These 1H-{14N} D-HMQC sequences differ not only by the order of 14N coherences evolving during the indirect evolution, t1, but also by the radio-frequency (rf) scheme used to excite and reconvert these coherences under Magic-Angle Spinning (MAS). Here, the SQ coherences are created by the application of center-band frequency-selective pulses, i.e. long and low-power rectangular pulses at the 14N Larmor frequency, ν0(14N), whereas the DQ coherences are excited and reconverted using rf irradiation either at ν0(14N) or at the 14N overtone frequency, 2ν0(14N). The overtone excitation is achieved either by constant frequency rectangular pulses or by frequency-swept pulses, specifically Wide-band, Uniform-Rate, and Smooth-Truncation (WURST) pulse shapes. The present article compares the performances of four different 1H-{14N} D-HMQC sequences, including those with 14N rectangular pulses at ν0(14N) for the indirect detection of homo-nuclear (i) 14N SQ or (ii) DQ coherences, as well as their overtone variants using (iii) rectangular or (iv) WURST pulses. The compared properties include: (i) the sensitivity, (ii) the spectral resolution in the 14N dimension, (iii) the rf requirements (power and pulse length), as well as the robustness to (iv) rf offset and (v) MAS frequency instabilities. Such experimental comparisons are carried out for γ-glycine and L-histidine.HCl monohydrate, which contain 14N sites subject to moderate quadrupole interactions. We demonstrate that the optimum choice of the 1H-{14N} D-HMQC method depends on the experimental goal. When the sensitivity and/or the robustness to offset are the major concerns, the D-HMQC sequence allowing the indirect detection of 14N SQ coherences should be employed. Conversely

  3. Dark matter direct-detection experiments

    NASA Astrophysics Data System (ADS)

    Marrodán Undagoitia, Teresa; Rauch, Ludwig

    2016-01-01

    In recent decades, several detector technologies have been developed with the quest to directly detect dark matter interactions and to test one of the most important unsolved questions in modern physics. The sensitivity of these experiments has improved with a tremendous speed due to a constant development of the detectors and analysis methods, proving uniquely suited devices to solve the dark matter puzzle, as all other discovery strategies can only indirectly infer its existence. Despite the overwhelming evidence for dark matter from cosmological indications at small and large scales, clear evidence for a particle explaining these observations remains absent. This review summarises the status of direct dark matter searches, focusing on the detector technologies used to directly detect a dark matter particle producing recoil energies in the keV energy scale. The phenomenological signal expectations, main background sources, statistical treatment of data and calibration strategies are discussed.

  4. An indirect hemagglutination test for the detection of antibodies to Clostridium chauvoei.

    PubMed

    Tamura, Y; Makie, H; Tanaka, S

    1985-06-01

    An indirect hemagglutination (IHA) test using sonicated extract as the antigen was developed for the detection of antibodies to Clostridium chauvoei. This antigen can be adsorbed onto glutaraldehyde-fixed sheep red blood cells treated with tannic acid and can be destroyed by trypsin and heat treatment. It corresponded well with the flagella of the organism, when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the gel diffusion test. No serological cross-reactivity was found in the IHA test when the antigen was tested against 4 species of clostridial antibodies. Our results suggest that the IHA test mainly detects antibodies against the flagella of C. chauvoei.

  5. Monoclonal antibodies and an indirect ELISA for detection of psychrotrophic bacteria in refrigerated milk.

    PubMed

    Gutiérrez, R; González, I; García, T; Carrera, E; Sanz, B; Hernández, P E; Martín, R

    1997-01-01

    Monoclonal antibodies generated against live cells of Pseudomonas fluorescens have been used in an indirect ELISA format for the detection of Pseudomonas spp. and related psychrotrophic bacteria in refrigerated milk. The immunorecognition of monoclonal antibodies adsorbed to bacteria bound to the wells of a microtiter plate was performed with rabbit anti-mouse immunoglobulins conjugated to horseradish peroxidase. Subsequent enzymic conversion of the substrate resulted in distinct absorbance differences when assaying milk samples containing psychrotrophic bacteria in the range 10(5) to 10(9) CFU ml(-1) . The detection threshold for the ELISA assay developed in this work is 10(5) CFU ml(-1).

  6. Indirect laser-induced breakdown of transparent thin gel layer for sensitive trace element detection

    NASA Astrophysics Data System (ADS)

    Xiu, Junshan; Bai, Xueshi; Negre, Erwan; Motto-Ros, Vincent; Yu, Jin

    2013-06-01

    Optical emissions from major and trace elements embodied in a transparent gel prepared from cooking oil were detected when the gel was spread in thin film on a metallic substrate and a plasma was induced on the substrate surface using nanosecond infrared pulsed laser. Such emissions are due to indirect breakdown of the coating layer. The generated plasma, a mixture of substances from the substrate, the layer, and the ambient gas, was characterized using emission spectroscopy. Temperature higher than 15 000 K determined in the plasma allows considering sensitive detection of trace elements in liquids, gels, biological samples, or thin films.

  7. Separation and indirect detection of small-chain peptides using chromophoric mobile phase additives.

    PubMed

    Yuan, D X; Pietrzyk, D J

    1990-06-22

    Ruthenium(II) 1,10-phenanthroline, Ru(phen)3(2+), and ruthenium(II) 2,2'-bipyridyl, Ru(bipy)3(2+), salts were evaluated as mobile phase additives for the liquid chromatographic separation of small-chain peptides on a polystyrene-divinylbenzene copolymeric (Hamilton PRP-1) stationary phase. In a basic mobile phase peptides are anions, and retention, resolution and detection occur because of the interactions between the stationary phase, the RuII complex and the peptide anion. Since the RuII complex concentration changes in the analyte band relative to the background eluent RuII complex concentration, the peptide can be detected by indirect photometric detection using the wavelength where the RuII complex absorbs. Peptide analyte peaks may be positive or negative depending on the counter-anion and its concentration. Small-chain peptides that do not contain chromophoric side-chains are detected without derivatization at about 0.1 nmol injected at a 3:1 signal-to-noise ratio. Factors that affect retention, resolution and indirect photometric detection are the RuII complex, its mobile phase concentration, mobile phase pH and solvent composition, and the type and concentration of the mobile phase counter-anion and/or buffer anion.

  8. Bringing isolated dark matter out of isolation: Late-time reheating and indirect detection

    NASA Astrophysics Data System (ADS)

    Erickcek, Adrienne L.; Sinha, Kuver; Watson, Scott

    2016-09-01

    In standard cosmology, the growth of structure becomes significant following matter-radiation equality. In nonthermal histories, where an effectively matter-dominated phase occurs due to scalar oscillations prior to big bang nucleosynthesis, a new scale at smaller wavelengths appears in the matter power spectrum. Density perturbations that enter the horizon during the early matter-dominated era (EMDE) grow linearly with the scale factor prior to the onset of radiation domination, which leads to enhanced inhomogeneity on small scales if dark matter (DM) thermally and kinetically decouples during the EMDE. The microhalos that form from these enhanced perturbations significantly boost the self-annihilation rate for dark matter. This has important implications for indirect detection experiments: the larger annihilation rate may result in observable signals from dark matter candidates that are usually deemed untestable. As a proof of principle, we consider binos in heavy supersymmetry with an intermediate extended Higgs sector and all other superpartners decoupled. We find that these isolated binos, which lie under the neutrino floor, can account for the dark matter relic density and decouple from the standard model early enough to preserve the enhanced small-scale inhomogeneity generated during the EMDE. If early forming microhalos survive as subhalos within larger microhalos, the resulting boost to the annihilation rate for bino dark matter near the pseudoscalar resonance exceeds the upper limit established by Fermi-LAT's observations of dwarf spheroidal galaxies. These DM candidates motivate the N -body simulations required to eliminate uncertainties in the microhalos' internal structure by exemplifying how an EMDE can enable Fermi-LAT to probe isolated dark matter.

  9. Simple J-factors and D-factors for indirect dark matter detection

    NASA Astrophysics Data System (ADS)

    Evans, N. W.; Sanders, J. L.; Geringer-Sameth, Alex

    2016-05-01

    J-factors (or D-factors) describe the distribution of dark matter in an astrophysical system and determine the strength of the signal provided by annihilating (or decaying) dark matter respectively. We provide simple analytic formulas to calculate the J-factors for spherical cusps obeying the empirical relationship between enclosed mass, velocity dispersion and half-light radius. We extend the calculation to the spherical Navarro-Frenk-White model, and demonstrate that our new formulas give accurate results in comparison to more elaborate Jeans models driven by Markov chain Monte Carlo methods. Of the known ultrafaint dwarf spheroidals, we show that Ursa Major II, Reticulum II, Tucana II and Horologium I have the largest J-factors and so provide the most promising candidates for indirect dark matter detection experiments. Amongst the classical dwarfs, Draco, Sculptor and Ursa Minor have the highest J-factors. We show that the behavior of the J-factor as a function of integration angle can be inferred for general dark halo models with inner slope γ and outer slope β . The central and asymptotic behavior of the J-factor curves are derived as a function of the dark halo properties. Finally, we show that models obeying the empirical relation on enclosed mass and velocity dispersion have J-factors that are most robust at the integration angle equal to the projected half-light radius of the dwarf spheroidal (dSph) divided by heliocentric distance. For most of our results, we give the extension to the D-factor which is appropriate for the decaying dark matter picture.

  10. Self-regulation and the hypothesis of experience-based selection: investigating indirect conscious control.

    PubMed

    Dorris, Derek C

    2009-09-01

    The assumption that the contents of our conscious visual experience directly control our fine-tuned, real-time motor activity has been challenged by neurological and psychophysical evidence that suggest the two processes work semi-independently of each other. Clark [Clark, A. (2001). Visual experience and motor action: Are the bonds too tight? The Philosophical Review, 110, 495-519; Clark, A. (2002). Is seeing all it seems? Action, reason and the grand illusion. Journal of Consciousness Studies, 9, 181-202; Clark, A. (2006). Vision as dance? Three challenges for sensori-motor contingency theory. PSYCHE, 12 (1). Available from http://www.psyche.cs.monash.edu.au] argues that such evidence implies a more indirect relationship between conscious visual experience and motor-control where the function of visual consciousness is not to control action but to select what actions are to be controlled. In this paper, I argue that this type of dynamic also exists at the wider level of self-regulation where conscious intent appears to indirectly control the enactment of the intended behaviour. I argue that by drawing parallels between Clark's proposed dynamic and self-regulation, the former is not only bolstered by a previously unrecognised source of support but our understanding of the latter can help to further elucidate Clark's proposed mechanism of indirect conscious control.

  11. Indirect immunofluorescence test and enzyme-linked immunosorbent assay for detection of Campylobacter pylori.

    PubMed Central

    Schaber, E; Umlauft, F; Stöffler, G; Aigner, F; Paulweber, B; Sandhofer, F

    1989-01-01

    An indirect immunofluorescence test (IIF) has been developed for detecting Campylobacter pylori in gastroduodenal biopsies. This test was compared with standard methods of C. pylori diagnosis, namely Gram staining and urease test, in a study population of 226 patients; 121 of the biopsy specimens were cultured for C. pylori as well. C. pylori colonization was detected in 154 of 226 patients (68%) by at least one of these methods (IIF, 96%; Gram staining, 78%; urease test, 60%; cultivation, 55%). Serum samples from 191 patients of the study population were screened for circulating antibodies to C. pylori by an indirect enzyme-linked immunosorbent assay with whole, untreated bacteria as antigen. Of these serum specimens, 140 (73%) revealed absorbance readings above the limit of positivity, which was determined as an optical density of greater than 0.35 at 405/620 nm. Of 132 serum specimens, 128 (97%) from patients with C. pylori detected in biopsies, but only 12 (20%) of 59 specimens from those without C. pylori detection showed elevated specific antibody levels. Our data revealed that IIF proved to be the superior rapid, sensitive, and specific diagnostic method. The correlation between microbiological findings and the immune response favors our enzyme-linked immunosorbent assay as an additional tool in C. pylori diagnosis. PMID:2644295

  12. Search for direct and indirect unitarity violation in neutrino oscillation experiments

    NASA Astrophysics Data System (ADS)

    Luo, Shu

    2014-08-01

    If three standard neutrinos mix with other degree of freedoms like sterile neutrinos, no matter how heavy the sterile neutrino masses are, it could result in the unitarity violation in the MNSP matrix. Nevertheless, the unitarity violation induced by the existence of light or heavy sterile neutrinos can have very different effects on neutrino oscillations, we call the former case direct unitarity violation and the later case the indirect unitarity violation. We will explain in this paper the difference of these two kinds of unitarity violations, then focus on the possibilities of searching the unitarity violation in neutrino oscillation experiments, of which the precision reactor experiments with multiple baselines are discussed in detail.

  13. [Detection of implicit memory for hard-to-encode tone sequences using an indirect recognition procedure].

    PubMed

    Ueda, Ayaka; Terasawa, Takafumi

    2010-10-01

    Two experiments, using an indirect recognition procedure (Terasawa & Ohta, 1993) as an implicit memory task, were conducted to examine implicit memory for random tone sequences. The indirect recognition procedure involved two sessions. The second session was a general recognition experiment consisting of learning and a recognition test phase. The effects of the learning during the first session were examined based on the recognition performance in the second session. The interval between the sessions was 10 weeks for experiment 1 and 8 weeks for experiment 2. In each session, participants were required to rate their liking for each of the sequences presented. In the second session, participants were required to respond to an old-new recognition test about the items just presented. The targets and distractors in the test consisted of stimuli presented or not presented in the first session. Analyses of the hits and false alarms showed an effect of the number of presentations in the first session. This result indicates an effect of long lasting implicit memory for tone sequences.

  14. Indirect competitive assays on DVD for direct multiplex detection of drugs of abuse in oral fluids.

    PubMed

    Zhang, Lingling; Li, Xiaochun; Li, Yunchao; Shi, Xiaoli; Yu, Hua-Zhong

    2015-02-03

    On-site oral fluid testing for drugs of abuse has become prominent in order to take immediate administrative action in an enforcement process. Herein, we report a DVD technology-based indirect competitive immunoassay platform for the quantitative detection of drugs of abuse. A microfluidic approach was adapted to prepare multiplex immunoassays on a standard DVD-R, an unmodified multimode DVD/Blu-Ray drive to read signal, and a free disc-quality analysis software program to process the data. The DVD assay platform was successfully demonstrated for the simultaneous, quantitative detection of drug candidates (morphine and cocaine) in oral fluids with high selectivity. The detection limit achieved was as low as 1.0 ppb for morphine and 5.0 ppb for cocaine, comparable with that of standard mass spectrometry and ELISA methods.

  15. Zero field NMR and NQR with selective pulses and indirect detection

    SciTech Connect

    Millar, J.M.; Thayer, A.M.; Bielecki, A.; Zax, D.B.; Pines, A.

    1985-08-01

    Zero field NMR and NQR spectra are obtained by the application of dc magnetic field pulses to a demagnetized sample. Pulsed dc fields allow for selective excitation of isotopic species and provide a means for coherent manipulation of the spin system in zero field. Using these selective pulses and level crossing techniques, indirect detection of a quadrupolar nucleus may be accomplished via protons without obtaining the proton background signal in the NQR spectrum. Experimental results from a variety of /sup 1/H, /sup 2/H, and /sup 14/N homo- and heteronuclear systems are presented as an illustration of these techniques.

  16. Minding the MeV gap: The indirect detection of low mass dark matter

    SciTech Connect

    Boddy, Kimberly K.; Kumar, Jason

    2016-06-21

    We consider the prospects for the indirect detection of low mass dark matter which couples dominantly to quarks. If the center of mass energy is below about 280 MeV, the kinematically allowed final states will be dominated by photons and neutral pions, producing striking signatures at gamma ray telescopes. In fact, an array of new instruments have been proposed, which would greatly improve sensitivity to photons in this energy range. We find that planned instruments can improve on current sensitivity to dark matter models of this type by up to a few orders of magnitude.

  17. Experience of the Indirect Neutron Radiography Method Based on the X-ray Imaging Plate at CARR

    NASA Astrophysics Data System (ADS)

    Wei, Guohai; Han, Songbai; Wang, Hongli; He, Linfeng; Wang, Yu; Wu, Meimei; Liu, Yuntao; Chen, Dongfeng

    Indirect neutron radiography (INR) experiments by X-ray imaging plate were carried out at the China Advanced Research Reactor (CARR). The key experiment parameters were optimized, especially the exposure time of the neutron converter andimaging plate. The optimized total exposure time is 37.25 min, it is two-fifths of the timebased on the film method under the same experimental conditions. The qualitative and quantitativeinspections were tested with dummy nuclear fuel rods and a water temperaturesensor ofa motor vehicle. The spring in the sensor and the defects of the dummy fuel rod's pellets can be qualitatively detected. The thickness of the tape at one position on the cladding of the dummy nuclear fuel rodwas quantitatively calculated to be 9.57 layers with the relative error of ±4.3%.

  18. Indirect detection of gravitino dark matter including its three-body decays

    SciTech Connect

    Choi, Ki-Young; Restrepo, Diego; Yaguna, Carlos E.; Zapata, Oscar E-mail: restrepo@udea.edu.co E-mail: pfozapata@eia.edu.co

    2010-10-01

    It was recently pointed out that in supersymmetric scenarios with gravitino dark matter and bilinear R-parity violation, gravitinos with masses below M{sub W} typically decay with a sizable branching ratio into the 3-body final states W*l and Z*ν. In this paper we study the indirect detection signatures of gravitino dark matter including such final states. First, we obtain the gamma ray spectrum from gravitino decays, which features a monochromatic contribution from the decay into γν and a continuum contribution from the three-body decays. After studying its dependence on supersymmetric parameters, we compute the expected gamma ray fluxes and derive new constraints, from recent FERMI data, on the R-parity breaking parameter and on the gravitino lifetime. Indirect detection via antimatter searches, a new possibility brought about by the three-body final states, is also analyzed. For models compatible with the gamma ray observations, the positron signal is found to be negligible whereas the antiproton one can be significant.

  19. The incidence of antinuclear antibodies (ANA) detected by indirect immunofluorescence assay (IFA) method.

    PubMed

    Karamehic, Jasenko; Subasic, Djemo; Gavrankapetanovic, Faris; Zecevic, Lamija; Eminovic, Izet; Memic, Senaid; Seric, Natasa; Drace, Zahida

    2007-01-01

    Human anti-nuclear antibodies (ANA) in Systemic Lupus Erythematosus (SLE) react specificaly with DNA, RNA, several proteins and ribonucleoproteins. Systemic Lupus Erythematosus is the classic type of polysystemic autoimmune disease. The high frequency of ANA is determined in these patients. Actually, all SLE patients are ANA positive. ANA testing by IFA (Indirect Immunofluorescence Assay) is an excellent screening tool for SLE cases, but it is not so highly specific test. Patients with connective tissue diseases, such as rheumatoid arthritis, scleroderma and dermatomyositis are also frequently positive. Results of IFA ANA have relative low specific degree, and for this reason the titration of these specimens to the end point is usually recommended. Indirect immunoflourescence is reference method for ANA testing. Common substrates are thin sections of rodent organs or various types of cell lines. The cell line substrates are preferable to organ sections, because these rapidly dividing cells have higher level for detection of certain clinically relevant antigens such as (e.g., centromere, SSA (Ro) and Scl-70). In this paper we present the results evaluation of ANA incidence, detected by IFA in serum specimens of corresponding clinical patients, during 2005 and 2006.

  20. How Good Are Indirect Tests at Detecting Recombination in Human mtDNA?

    PubMed Central

    White, Daniel James; Bryant, David; Gemmell, Neil John

    2013-01-01

    Empirical proof of human mitochondrial DNA (mtDNA) recombination in somatic tissues was obtained in 2004; however, a lack of irrefutable evidence exists for recombination in human mtDNA at the population level. Our inability to demonstrate convincingly a signal of recombination in population data sets of human mtDNA sequence may be due, in part, to the ineffectiveness of current indirect tests. Previously, we tested some well-established indirect tests of recombination (linkage disequilibrium vs. distance using D′ and r2, Homoplasy Test, Pairwise Homoplasy Index, Neighborhood Similarity Score, and Max χ2) on sequence data derived from the only empirically confirmed case of human mtDNA recombination thus far and demonstrated that some methods were unable to detect recombination. Here, we assess the performance of these six well-established tests and explore what characteristics specific to human mtDNA sequence may affect their efficacy by simulating sequence under various parameters with levels of recombination (ρ) that vary around an empirically derived estimate for human mtDNA (population parameter ρ = 5.492). No test performed infallibly under any of our scenarios, and error rates varied across tests, whereas detection rates increased substantially with ρ values > 5.492. Under a model of evolution that incorporates parameters specific to human mtDNA, including rate heterogeneity, population expansion, and ρ = 5.492, successful detection rates are limited to a range of 7−70% across tests with an acceptable level of false-positive results: the neighborhood similarity score incompatibility test performed best overall under these parameters. Population growth seems to have the greatest impact on recombination detection probabilities across all models tested, likely due to its impact on sequence diversity. The implications of our findings on our current understanding of mtDNA recombination in humans are discussed. PMID:23665874

  1. Indirect detection by semiconductor laser-induced fluorometry in micellar electrokinetic chromatography

    NASA Astrophysics Data System (ADS)

    Kaneta, Takashi; Imasaka, Totaro

    1995-05-01

    Indirect fluorescence detection of electrically neutral compounds separated by micellar electrokinetic chromatography is performed using a semiconductor laser as an exciting light source. Oxazine 750 is used as a visualizing agent of which absorption maximum is near 680 nm. A surfactant, tetradecyltrimethylammonium chloride, is used to form micelles and to prevent adsorption of oxazine 750 with a positive charge on the capillary wall negatively charged. This surfactant coats on the capillary wall so that oxazine 750 is repulsed electrically on the capillary wall. In this technique, some aromatic compounds with relatively polar functional groups, such as aniline and nitrobenzene, could be separated and detected, while nonpolar compounds such as benzene and toluene can not be detected. The range of the detection limit is from 4.2 X 10-4 to 1.6 X 10-3 M (S/N equals 3) for the aromatic compounds. The detection mechanism is based on enhancement of the fluorescence intensity in the micellar solution and on exclusion of the fluorophore attached at the hydrophilic moiety of the micelle by a hydrophilic sample.

  2. Indirect detection of Particle Dark Matter with gamma rays - status and perspectives

    NASA Astrophysics Data System (ADS)

    Conrad, Jan

    2014-03-01

    In this contribution I review the present status and discuss some prospects for indirect detection of dark matter with gamma rays. Thanks mainly to the Fermi Large Area Telescope (Fermi-LAT), searches in gamma-rays have reached sensitivities that allow to probe the most interesting parameter space of the weakly interacting massive particles (WIMP) paradigm. This gain in sensitivity is naturally accompanied by a number of detection claims or indications. At WIMP masses above roughly a TeV current Imaging Air Cherenkov Telescopes (HESS, VERITAS, MAGIC) become more sensitive than the Fermi-LAT, the most promising recent development being the first light for the second phase HESS II telescope with significantly lower energy threshold. Predictions for the next generation air Cherenkov telescope, Cherenkov Telescope Array (CTA), together with forecasts on future Fermi-LAT constraints arrive at the exciting possibility that the cosmological benchmark cross-section could be probed from masses of a few GeV to a few TeV. Consequently, non-detection would pose a challenge to the WIMP paradigm, but the reached sensitivities also imply that-optimistically-a detection within the next decade is in the cards. Time allowing, I will comment on complementarity between the different approaches to WIMP detection.

  3. Progress in indirect and direct-drive planar experiments on hydrodynamic instabilities at the ablation front

    SciTech Connect

    Casner, A. Masse, L.; Huser, G.; Galmiche, D.; Liberatore, S.; Riazuelo, G.; Delorme, B.; Martinez, D.; Remington, B.; Smalyuk, V. A.; Igumenshchev, I.; Michel, D. T.; Froula, D.; Seka, W.; Goncharov, V. N.; Olazabal-Loumé, M.; Nicolaï, Ph.; Breil, J.; Tikhonchuk, V. T.; Fujioka, S.; and others

    2014-12-15

    Understanding and mitigating hydrodynamic instabilities and the fuel mix are the key elements for achieving ignition in Inertial Confinement Fusion. Cryogenic indirect-drive implosions on the National Ignition Facility have evidenced that the ablative Rayleigh-Taylor Instability (RTI) is a driver of the hot spot mix. This motivates the switch to a more flexible higher adiabat implosion design [O. A. Hurricane et al., Phys. Plasmas 21, 056313 (2014)]. The shell instability is also the main candidate for performance degradation in low-adiabat direct drive cryogenic implosions [Goncharov et al., Phys. Plasmas 21, 056315 (2014)]. This paper reviews recent results acquired in planar experiments performed on the OMEGA laser facility and devoted to the modeling and mitigation of hydrodynamic instabilities at the ablation front. In application to the indirect-drive scheme, we describe results obtained with a specific ablator composition such as the laminated ablator or a graded-dopant emulator. In application to the direct drive scheme, we discuss experiments devoted to the study of laser imprinted perturbations with special phase plates. The simulations of the Richtmyer-Meshkov phase reversal during the shock transit phase are challenging, and of crucial interest because this phase sets the seed of the RTI growth. Recent works were dedicated to increasing the accuracy of measurements of the phase inversion. We conclude by presenting a novel imprint mitigation mechanism based on the use of underdense foams. The foams induce laser smoothing by parametric instabilities thus reducing the laser imprint on the CH foil.

  4. Isotachophoresis on a chip with indirect fluorescence detection as a field deployable system for analysis of carboxylic acids.

    PubMed

    Smejkal, Petr; Breadmore, Michael C; Guijt, Rosanne M; Foret, František; Bek, Fritz; Macka, Mirek

    2012-11-01

    ITP with indirect fluorescence detection (IFD) was introduced three decades ago. Despite this fact, the method has never become widely adopted. The main aim of this work was to utilize the ITP-IFD for the separation of carboxylic acids by using a commercially available, portable, microfluidic chip electrophoresis system. On the 16.8-mm effective length separation channel, a maximum of eight carboxylic acids could be separated, with LOD values in a range from 0.12 to 0.4 mM. The commercial chips used for all experiments have multichannel structures important for analysis of more than one sample per a chip in case of standard use. This multichannel structure was used to investigate the possibility of multiple sample loading for ITP separation. Application of ITP-IFD was investigated for analysis of benzoate in diet soft drinks and the results were in good agreement with results of a CE method.

  5. Indirect-drive ablative Rayleigh-Taylor growth experiments on the Shenguang-II laser facility

    SciTech Connect

    Wu, J. F.; Fan, Z. F.; Zheng, W. D.; Wang, M.; Pei, W. B.; Zhu, S. P.; Zhang, W. Y.; Miao, W. Y.; Yuan, Y. T.; Cao, Z. R.; Deng, B.; Jiang, S. E.; Liu, S. Y.; Ding, Y. K.; Wang, L. F.; Ye, W. H. He, X. T.

    2014-04-15

    In this research, a series of single-mode, indirect-drive, ablative Rayleigh-Taylor (RT) instability experiments performed on the Shenguang-II laser facility [X. T. He and W. Y. Zhang, Eur. Phys. J. D 44, 227 (2007)] using planar target is reported. The simulation results from the one-dimensional hydrocode for the planar foil trajectory experiment indicate that the energy flux at the hohlraum wall is obviously less than that at the laser entrance hole. Furthermore, the non-Planckian spectra of x-ray source can strikingly affect the dynamics of the foil flight and the perturbation growth. Clear images recorded by an x-ray framing camera for the RT growth initiated by small- and large-amplitude perturbations are obtained. The observed onset of harmonic generation and transition from linear to nonlinear growth regime is well predicted by two-dimensional hydrocode simulations.

  6. Helping direct and indirect victims of national terror: experiences of Israeli social workers.

    PubMed

    Shamai, Michal; Ron, Pnina

    2009-01-01

    In this study we explored the subjective experience and the meaning attached to it by Israeli social workers who provide help to direct and indirect victims of national terror attacks. A qualitative methodology, based on grounded theory tradition, was used to conduct and analyze interviews with 29 social workers from three types of agencies (municipal social services, general hospitals, and the National Insurance Institute) from various parts of the country. Based on the data, three main themes were constructed: (a) professional and personal functioning during intervention, (b) the immediate and long-term impact of intervening with terror attacks, and (c) the meaning attached to the social worker's role in intervening with victims. Overall, the findings show that the social workers experienced symptoms similar to those of secondary traumatic stress disorder (STSD) for a few days only, but in the long-term, they perceived their experience of helping victims of terror attacks as leading to personal and professional growth.

  7. Comparisons between conventional optical imaging and parametric indirect microscopic imaging on human skin detection

    NASA Astrophysics Data System (ADS)

    Liu, Guoyan; Gao, Kun; Liu, Xuefeng; Ni, Guoqiang

    2016-10-01

    We report a new method, polarization parameters indirect microscopic imaging with a high transmission infrared light source, to detect the morphology and component of human skin. A conventional reflection microscopic system is used as the basic optical system, into which a polarization-modulation mechanics is inserted and a high transmission infrared light source is utilized. The near-field structural characteristics of human skin can be delivered by infrared waves and material coupling. According to coupling and conduction physics, changes of the optical wave parameters can be calculated and curves of the intensity of the image can be obtained. By analyzing the near-field polarization parameters in nanoscale, we can finally get the inversion images of human skin. Compared with the conventional direct optical microscope, this method can break diffraction limit and achieve a super resolution of sub-100nm. Besides, the method is more sensitive to the edges, wrinkles, boundaries and impurity particles.

  8. Analysis of glycolysis metabolites by capillary zone electrophoresis with indirect UV detection.

    PubMed

    Shen, P; Hauri, D; Ross, J; Oefner, P J

    1996-01-01

    The glycolysis metabolites glucose 6-phosphate (G6-P), fructose 6-phosphate (F6-P), fructose 1,6-bisphosphate (F1,6-BP), fructose 2,6-bisphosphate (F2,6-BP), glyceraldehyde phosphate (GAP), dihydroxyacetone phosphate (DHAP), phosphoenolpyruvate (PEP), pyruvate, and lactate were analyzed by capillary zone electrophoresis (CZE) with indirect UV detection. The chromophores phthalic acid, sorbic acid, and 4-hydroxybenzoic acid were studied as background electrolytes. Both detection sensitivity and resolution were found to depend on the pH and the concentration of the carrier electrolyte. Optimum separation and detection of the phosphate compounds were accomplished upon reversal of electroendosmotic flow (EOF) with OFM Anion-BT (Waters Corp., Milford, MA) at a concentration of 4-6 mM 4-hydroxybenzoic acid, pH 11.6-12.0, with the detection wave-length set at 280 nm. The highly alkaline pH allowed the successful separation of the isomers F6-P and G6-P, as well as F1,6-BP and F2,6-BP, respectively. The effect of sample ionic strength on the detection limits of G6-P, F6-P, F1,6-BP, and F2,6-BP was also investigated: These limits ranged from 1 to 3 microM in both low- and high-ionic-strength samples. However, high Mg2+ concentrations in the sample led to a progressive loss of resolution between F1,6-BP and F2,6-BP, unless the inlet reservoir was replenished with fresh electrolyte after every injection. Linearity of detection was observed over one to two orders of magnitude.

  9. Indirect monitoring shot-to-shot shock waves strength reproducibility during pump–probe experiments

    SciTech Connect

    Pikuz, T. A.; Faenov, A. Ya.; Ozaki, N.; Habara, H.; Tanaka, K. A.; Kodama, R.; Hartley, N. J.; Matsuoka, T.; Albertazzi, B.; Matsuyama, S.; Yamauchi, K.; Ochante, R.; Takahashi, K.; Sueda, K.; Tange, Y.; Sakata, O.; Sekine, T.; Sato, T.; Umeda, Y.; Inubushi, Y.; and others

    2016-07-21

    We present an indirect method of estimating the strength of a shock wave, allowing on line monitoring of its reproducibility in each laser shot. This method is based on a shot-to-shot measurement of the X-ray emission from the ablated plasma by a high resolution, spatially resolved focusing spectrometer. An optical pump laser with energy of 1.0 J and pulse duration of ∼660 ps was used to irradiate solid targets or foils with various thicknesses containing Oxygen, Aluminum, Iron, and Tantalum. The high sensitivity and resolving power of the X-ray spectrometer allowed spectra to be obtained on each laser shot and to control fluctuations of the spectral intensity emitted by different plasmas with an accuracy of ∼2%, implying an accuracy in the derived electron plasma temperature of 5%–10% in pump–probe high energy density science experiments. At nano- and sub-nanosecond duration of laser pulse with relatively low laser intensities and ratio Z/A ∼ 0.5, the electron temperature follows T{sub e} ∼ I{sub las}{sup 2/3}. Thus, measurements of the electron plasma temperature allow indirect estimation of the laser flux on the target and control its shot-to-shot fluctuation. Knowing the laser flux intensity and its fluctuation gives us the possibility of monitoring shot-to-shot reproducibility of shock wave strength generation with high accuracy.

  10. Indirect monitoring shot-to-shot shock waves strength reproducibility during pump-probe experiments

    NASA Astrophysics Data System (ADS)

    Pikuz, T. A.; Faenov, A. Ya.; Ozaki, N.; Hartley, N. J.; Albertazzi, B.; Matsuoka, T.; Takahashi, K.; Habara, H.; Tange, Y.; Matsuyama, S.; Yamauchi, K.; Ochante, R.; Sueda, K.; Sakata, O.; Sekine, T.; Sato, T.; Umeda, Y.; Inubushi, Y.; Yabuuchi, T.; Togashi, T.; Katayama, T.; Yabashi, M.; Harmand, M.; Morard, G.; Koenig, M.; Zhakhovsky, V.; Inogamov, N.; Safronova, A. S.; Stafford, A.; Skobelev, I. Yu.; Pikuz, S. A.; Okuchi, T.; Seto, Y.; Tanaka, K. A.; Ishikawa, T.; Kodama, R.

    2016-07-01

    We present an indirect method of estimating the strength of a shock wave, allowing on line monitoring of its reproducibility in each laser shot. This method is based on a shot-to-shot measurement of the X-ray emission from the ablated plasma by a high resolution, spatially resolved focusing spectrometer. An optical pump laser with energy of 1.0 J and pulse duration of ˜660 ps was used to irradiate solid targets or foils with various thicknesses containing Oxygen, Aluminum, Iron, and Tantalum. The high sensitivity and resolving power of the X-ray spectrometer allowed spectra to be obtained on each laser shot and to control fluctuations of the spectral intensity emitted by different plasmas with an accuracy of ˜2%, implying an accuracy in the derived electron plasma temperature of 5%-10% in pump-probe high energy density science experiments. At nano- and sub-nanosecond duration of laser pulse with relatively low laser intensities and ratio Z/A ˜ 0.5, the electron temperature follows Te ˜ Ilas2/3. Thus, measurements of the electron plasma temperature allow indirect estimation of the laser flux on the target and control its shot-to-shot fluctuation. Knowing the laser flux intensity and its fluctuation gives us the possibility of monitoring shot-to-shot reproducibility of shock wave strength generation with high accuracy.

  11. [Determination of amino acids in honey by capillary electrophoresis with indirect ultraviolet detection].

    PubMed

    Zhou, Xianjing; Shi, Yanping

    2013-07-01

    A method of capillary electrophoresis with indirect ultraviolet (UV) detection was developed for the separation and determination of nine amino acids such as lysine, tryptophan, glutamic acid, etc. The effects of sodium dihydrogen phosphates concentration, pH of buffer and sample injection type and time on the reproducibility and efficiency were investigated. The optimum injection time was 5 s at 5 kPa. The optimum electrophoretic conditions were as follow: 10 mmol/L sodium dihydrogen phosphates (pH 10. 2) containing 0. 5 mmol/L cetrimonium bromide, 20 mmol/L nicotinic acid and 10% (v/v) methanol as running buffer, applied voltage of - 15 kV, detection wavelength of 220 nm. The base line separation of the nine amino acids was achieved successfully within 11 min. The lowest detection limit was 0. 3 mg/L. All of the nine analytes showed good linearities within 1. 0 - 1000 mg/L. The relative standard deviations of migration time and peak area were 0. 64% - 5. 83%. The recoveries of the eight amino acids spiked in a real sample were between 60. 00% and 118.37%. The method was applied in the determination of the amino acids in honey samples from different nectar plants and origins. Prolin, serine and aspartic acid were found in five honey samples, and tryptophan was only found in a litchi honey sample. This method can provide good reference to the evaluation of the quality and nectar origin of honey.

  12. An indirect enzyme linked immunosorbent assay for the detection of bovine antibodies to multiple Leptospira serovars

    PubMed Central

    2004-01-01

    Abstract An indirect enzyme linked immunosorbent assay was developed for the detection of bovine antibodies to multiple pathogenic Leptospira serovars, including canicola, copenhageni (represents icterohaemorrhagiae), grippotyphosa, hardjobovis, pomona, and sejroe. The antigen utilized in this assay was a sonicated mixture of equal parts of killed whole cells of each of the 6 serovars named above. A mouse monoclonal antibody against bovine immunoglobulin (Ig)G1 that was conjugated with horseradish peroxidase was used for detection of bound antibodies. This assay was evaluated with sera (n = 3107) that were microscopic agglutination test (MAT)-negative (at a 1:100 dilution) for each of the 6 serovars listed above and sera (n = 601) that were MAT-positive (at a 1:100 dilution) for 1, or any combination of the 6 listed serovars. In addition, sera from serial weekly bleedings of cows, which were individually experimentally infected with serovars hardjobovis, copenhageni, grippotyphosa, or canicola, were also tested in this assay. At an optimal cut-off point determined by receiver operating characteristic (ROC) curve analysis, the relative sensitivity and specificity of the assay were 93.5% (95% confidence interval = 91.2% to 95.3%) and 94.7% (95% confidence interval = 93.9% to 95.5%), respectively. This assay was able to detect antibody in the sera of animals experimentally infected with serovar hardjobovis as early as 1 week postinoculation PMID:14979428

  13. An indirect enzyme linked immunosorbent assay for the detection of bovine antibodies to multiple Leptospira serovars.

    PubMed

    Surujballi, Om; Mallory, Maria

    2004-01-01

    An indirect enzyme linked immunosorbent assay was developed for the detection of bovine antibodies to multiple pathogenic Leptospira serovars, including canicola, copenhageni (represents icterohaemorrhagiae), grippotyphosa, hardjobovis, pomona, and sejroe. The antigen utilized in this assay was a sonicated mixture of equal parts of killed whole cells of each of the 6 serovars named above. A mouse monoclonal antibody against bovine immunoglobulin (Ig)G1 that was conjugated with horseradish peroxidase was used for detection of bound antibodies. This assay was evaluated with sera (n = 3107) that were microscopic agglutination test (MAT)-negative (at a 1:100 dilution) for each of the 6 serovars listed above and sera (n = 601) that were MAT-positive (at a 1:100 dilution) for 1, or any combination of the 6 listed serovars. In addition, sera from serial weekly bleedings of cows, which were individually experimentally infected with serovars hardjobovis, copenhageni, grippotyphosa, or canicola, were also tested in this assay. At an optimal cut-off point determined by receiver operating characteristic (ROC) curve analysis, the relative sensitivity and specificity of the assay were 93.5% (95% confidence interval = 91.2% to 95.3%) and 94.7% (95% confidence interval = 93.9% to 95.5%), respectively. This assay was able to detect antibody in the sera of animals experimentally infected with serovar hardjobovis as early as 1 week postinoculation.

  14. An indirect microimmunofluorescence test for detection of chlamydial antibodies in ovine fetal fluids.

    PubMed

    Sanderson, T P; Andersen, A A; Miller, L D; Andrews, J J; Janke, B H; Larson, D L; Schwartz, K J

    1994-07-01

    The objective of this study was to evaluate an indirect microimmunofluorescence test (IMIF) for detection of chlamydial antibodies in serum and/or thoracic fluids of aborted ovine fetuses. One hundred eighty-two ovine fetuses, including 64 fetuses from 40 ewes that were experimentally infected with an ovine abortion strain of Chlamydia psittaci at gestation days 90-100, 10 fetuses from 6 normal ewes, and 108 fetuses selected from those received at the Iowa Veterinary Diagnostic Laboratory, were evaluated in this study. Fetuses from experimentally infected ewes were examined 4-60 days after inoculation. The IMIF findings were compared with the results of complement fixation serology for chlamydiae and concentrations of immunoglobulin (IgG). Chlamydiae-specific antibodies were detected by IMIF in 28 of 38 fetuses infected with C. psittaci. Elevated levels of IgG and IMIF titers > or = 1:8 were consistent findings in ovine fetuses infected with chlamydiae for more than 24 days. IgG levels and titers of chlamydial antibodies increased with maturity of the fetus and duration of chlamydial infection. Chlamydial antibodies were not detected with the complement fixation test. Fluids from ovine fetuses aborted as a result of other causes also were examined, and IMIF results were negative. The results of this study indicate that the IMIF is a useful and relatively rapid test for identification of chlamydial antibodies in ovine fetuses.

  15. An indirect measurement of the width of the w boson at the D0 experiment

    SciTech Connect

    Telford, Paul

    2006-01-01

    This thesis presents an indirect measurement of the width of the W boson using data collected at the D0 experiment, a multipurpose particle detector utilizing the Fermilab Tevatron. The W width was determined from the ratio of W → μv to Z → μ+μ- cross sections to be ΓW = 2168 ± 22(stat) ± 62(syst)$+24\\atop{-16}$(pdf) ±4(other) MeV, in good agreement with the Standard Model prediction and other experimental measurements. In addition there is a description of how work made towards this measurement has been used to improve the parameterized detector simulation, a vital tool in the obtention of physics results from signals observed in the detector, and in estimating the uncertainty due to choice of PDF, which is of interest for all measurements made at hadron colliders.

  16. Exercise Experiences and Changes in Affective Attitude: Direct and Indirect Effects of In Situ Measurements of Experiences

    PubMed Central

    Sudeck, Gorden; Schmid, Julia; Conzelmann, Achim

    2016-01-01

    Objectives: The purpose of this study was to examine the relationship between exercise experiences (perceptions of competence, perceived exertion, acute affective responses to exercise) and affective attitudes toward exercise. This relationship was analyzed in a non-laboratory setting during a 13-weeks exercise program. Materials and Methods: 56 women and 49 men (aged 35–65 years; Mage = 50.0 years; SD = 8.2 years) took part in the longitudinal study. Affective responses to exercise (affective valence, positive activation, calmness) as well as perceptions of competence and perceived exertion were measured at the beginning, during, and end of three exercise sessions within the 13-weeks exercise program. Affective attitude toward exercise were measured before and at the end of the exercise program. A two-level path analysis was conducted. The direct and indirect effects of exercise experiences on changes in affective attitude were analyzed on the between-person level: firstly, it was tested whether perceptions of competence and perceived exertion directly relate to changes in affective attitude. Secondly, it was assessed whether perceptions of competence and perceived exertion indirectly relate to changes in affective attitudes—imparted via the affective response during exercise. Results and Conclusion: At the between-person level, a direct effect on changes in affective attitude was found for perceptions of competence (β = 0.24, p < 0.05). The model revealed one significant indirect pathway between perceived exertion and changes in affective attitude via positive activation: on average, the less strenuous people perceive physical exercise to be, the more awake they will feel during exercise (β = -0.57, p < 0.05). Those people with higher average levels of positive activation during exercise exhibit more improvements in affective attitudes toward exercise from the beginning to the end of the 13-weeks exercise program (β = 0.24, p < 0.05). Main study results

  17. Evaluation of three simple direct or indirect carbonyl detection methods for characterization of oxidative modifications of proteins.

    PubMed

    Vásquez-Garzón, Verónica R; Rouimi, Patrick; Jouanin, Isabelle; Waeg, Georg; Zarkovic, Neven; Villa-Treviño, Saul; Guéraud, Françoise

    2012-05-01

    Among disruptions induced by oxidative stress, modifications of proteins, particularly irreversible carbonylation, are associated with the development of several diseases, including cardiovascular diseases, neurodegenerative diseases, and cancer. Carbonylation of proteins can occur directly or indirectly through the adduction of lipid oxidation products. In this study, three classical and easy-to-perform techniques to detect direct or indirect carbonylation of proteins were compared. A model protein apomyoglobin and a complex mixture of rat liver cytosolic proteins were exposed to cumene hydroperoxide oxidation or adduction to the lipid peroxidation product 4-hydroxynonenal in order to test direct or indirect carbonylation, respectively. The technique using a specific anti-4-hydroxynonenal-histidine adduct antibody was effective to detect in vitro modification of model apomyoglobin and cytosolic proteins by 4-hydroxynonenal but not by direct carbonylation which was achieved by techniques using biotin-coupled hydrazide or dinitrophenylhydrazine derivatization of carbonyls. Sequential use of these methods enabled the detection of both direct and indirect carbonyl modification in proteins, although constitutively biotinylated proteins were detected by biotin-hydrazide. Although rather classical and efficient, methods for carbonyl detection on proteins in oxidative stress studies may be biased by some artifactual detections and complicated by proteins multimerizations. The use of more and more specific available antibodies is recommended to complete detection of lipid peroxidation product adducts on proteins.

  18. Exchange facilitated indirect detection of hyperpolarized 15ND 2-amido-glutamine

    NASA Astrophysics Data System (ADS)

    Barb, A. W.; Hekmatyar, S. K.; Glushka, J. N.; Prestegard, J. H.

    2011-10-01

    Hyperpolarization greatly enhances opportunities to observe in vivo metabolic processes in real time. Accessible timescales are, however, limited by nuclear spin relaxation times, and sensitivity is limited by magnetogyric ratios of observed nuclei. The majority of applications to date have involved direct 13C observation of metabolites with non-protonated carbons at sites of interest ( 13C enriched carbonyls, for example), a choice that extends relaxation times and yields moderate sensitivity. Interest in 15N containing metabolites is equally high but non-protonated sites are rare and direct 15N observation insensitive. Here an approach is demonstrated that extends applications to protonated 15N sites with high sensitivity. The normally short relaxation times are lengthened by initially replacing protons (H) with deuterons (D) and low sensitivity detection of 15N is avoided by indirect detection through protons reintroduced by H/D exchange. A pulse sequence is presented that periodically samples 15N polarization at newly protonated sites by INEPT transfer to protons while returning 15N magnetization of deuterated sites to the + Z axis to preserve polarization for subsequent samplings. Applications to 15ND 2-amido-glutamine are chosen for illustration. Glutamine is an important regulator and a direct donor of nitrogen in cellular metabolism. Potential application to in vivo observation is discussed.

  19. Development of an indirect competitive ELISA for simultaneous detection of enrofloxacin and ciprofloxacin*

    PubMed Central

    Zhang, Hai-tang; Jiang, Jin-qing; Wang, Zi-liang; Chang, Xin-yao; Liu, Xing-you; Wang, San-hu; Zhao, Kun; Chen, Jin-shan

    2011-01-01

    Modified 1-ethyl-3-(3-dimethylaminopropy) carbodiimide (EDC) method was employed to synthesize the artificial antigen of enrofloxacin (ENR), and New Zealand rabbits were used to produce anti-ENR polyclonal antibody (pAb). Based on the checkerboard titration, an indirect competitive enzyme-linked immunosorbent assay (ELISA) standard curve was established. This assay was sensitive and had a linear range from 0.6 to 148.0 μg/kg (R 2=0.9567), with the half maximal inhibitory concentration (IC50) and limit of detection (LOD) values of 9.4 μg/kg and 0.2 μg/kg, respectively. Of all the competitive analogues, the produced pAb exhibited a high cross-reactivity to ciprofloxacin (CIP) (87%), the main metabolite of ENR in tissues. After optimization, the matrix effects can be ignored using a 10-fold dilution in beef and 20-fold dilution in pork. The overall recoveries and coefficients of variation (CVs) were in the ranges of 86%–109% and 6.8%–13.1%, respectively. It can be concluded that the established ELISA method is suitable for simultaneous detection of ENR and CIP in animal tissues. PMID:22042652

  20. Micro-indirect hemagglutination test for detection of antibody against transmissible gastroenteritis virus of pigs.

    PubMed Central

    Shimizu, M; Shimizu, Y

    1977-01-01

    A micro-indirect hemagglutination (IHA) test was developed for detecting antibody against transmissible gastroenteritis (TGE) virus of pigs. TGE virus propagated in swine kidney cell cultures was highly purified and concentrated by the combination of ammonium sulfate precipitation, treatment with fluorocarbon, and sucrose density gradient centrifugation. Tanned sheep erythrocytes were sensitized with purified virus for use in the IHA test. The results of testing 104 serum samples collected from pigs in the field indicated that the IHA antibody titers were approximately five times higher than those obtained by a serum neutralization test and that there was good correlation between the antibody titers determined by the two tests. High IHA antibody titers developed in pigs experimentally exposed to virulent TGE virus. Sensitized sheep erythrocytes were stable under long-term storage at 4 degrees C (at least for 50 days). The conclusions made are that the IHA test described is more sensitive than the serum neutralization test for the detection of TGE antibody and may be of value for serodiagnosis of TGE. Images PMID:197119

  1. Development and application of an indirect ELISA for detection of antibodies against avian hepatitis E virus.

    PubMed

    Zhao, Qin; Sun, Yani; Zhao, Jinan; Hu, Shoubin; Zhao, Feifei; Chen, Fuyong; Clavijo, Alfonso; Zhou, En-Min; Xiao, Yihong

    2013-01-01

    An indirect enzyme-linked immunosorbent assay (iELISA) that could detect immunoglobulin G antibodies against avian hepatitis E virus (HEV) was developed. This assay employs a truncated C-terminal 268-amino acid recombinant ORF2 protein from an avian HEV genotype 3 strain isolated in China (CaHEV) as the coating antigen. The antigen concentration and serum dilution were optimized using a checkerboard titration. A cut-off value of 0.368 at OD(450nm) was determined by testing 120 positive and 200 negative chicken sera for avian HEV antibodies using the two-graph receiver operating characteristic (TG-ROC) analysis. This iELISA has a sensitivity of 96.1% and a specificity of 95.8%. The overall agreement between the iELISA and a corresponding Western blot was 97%. The iELISA was used to evaluate the seroprevalence of avian HEV in poultry farms in the Shandong province. The avian HEV seropositive rate of 35.9% was determined by testing 1871 serum samples that were collected from 10 chicken flocks ranged from 10 to 60 weeks of age. The iELISA that was developed in this study can be used for detection of immunoglobulin G antibodies against avian HEV.

  2. Indirect Reciprocity, Resource Sharing, and Environmental Risk: Evidence from Field Experiments in Siberia.

    PubMed

    Howe, E Lance; Murphy, James J; Gerkey, Drew; West, Colin Thor

    2016-01-01

    Integrating information from existing research, qualitative ethnographic interviews, and participant observation, we designed a field experiment that introduces idiosyncratic environmental risk and a voluntary sharing decision into a standard public goods game. Conducted with subsistence resource users in rural villages on the Kamchatka Peninsula in Northeast Siberia, we find evidence consistent with a model of indirect reciprocity and local social norms of helping the needy. When participants are allowed to develop reputations in the experiments, as is the case in most small-scale societies, we find that sharing is increasingly directed toward individuals experiencing hardship, good reputations increase aid, and the pooling of resources through voluntary sharing becomes more effective. We also find high levels of voluntary sharing without a strong commitment device; however, this form of cooperation does not increase contributions to the public good. Our results are consistent with previous experiments and theoretical models, suggesting strategic risks tied to rewards, punishments, and reputations are important. However, unlike studies that focus solely on strategic risks, we find the effects of rewards, punishments, and reputations are altered by the presence of environmental factors. Unexpected changes in resource abundance increase interdependence and may alter the costs and benefits of cooperation, relative to defection. We suggest environmental factors that increase interdependence are critically important to consider when developing and testing theories of cooperation.

  3. Indirect Reciprocity, Resource Sharing, and Environmental Risk: Evidence from Field Experiments in Siberia

    PubMed Central

    Howe, E. Lance; Murphy, James J.; Gerkey, Drew; West, Colin Thor

    2016-01-01

    Integrating information from existing research, qualitative ethnographic interviews, and participant observation, we designed a field experiment that introduces idiosyncratic environmental risk and a voluntary sharing decision into a standard public goods game. Conducted with subsistence resource users in rural villages on the Kamchatka Peninsula in Northeast Siberia, we find evidence consistent with a model of indirect reciprocity and local social norms of helping the needy. When participants are allowed to develop reputations in the experiments, as is the case in most small-scale societies, we find that sharing is increasingly directed toward individuals experiencing hardship, good reputations increase aid, and the pooling of resources through voluntary sharing becomes more effective. We also find high levels of voluntary sharing without a strong commitment device; however, this form of cooperation does not increase contributions to the public good. Our results are consistent with previous experiments and theoretical models, suggesting strategic risks tied to rewards, punishments, and reputations are important. However, unlike studies that focus solely on strategic risks, we find the effects of rewards, punishments, and reputations are altered by the presence of environmental factors. Unexpected changes in resource abundance increase interdependence and may alter the costs and benefits of cooperation, relative to defection. We suggest environmental factors that increase interdependence are critically important to consider when developing and testing theories of cooperation PMID:27442434

  4. Autoantibody detection with indirect immunofluorescence on HEp-2 cells: starting serum dilutions for systemic rheumatic diseases.

    PubMed

    González, Delia Almeida; León, Antonio Cabrera de; Varela, Alfredo Roces; García, Miriam García; Rahola, Marta de Sequera; Pérez, María Del Cristo Rodríguez; Hernández, Ana González; Falcón, María José Falcón; Díaz, Buenaventura Brito

    2011-10-30

    Antinuclear antibodies (ANA) are determined, among other reasons, to identify samples which need a second test to detect the associated specificities. Our aim was to evaluate the clinical and economic impact generated by using an initial dilution for ANA of 1:160. We analyzed all samples for which ANA, anti-ENA and anti-dsDNA were requested over a 1-year period. ANA were detected by indirect immunofluorescence. Anti-ENA were analyzed with a combination of techniques. Anti-dsDNA were detected by radioimmunoassay. Cost analysis was performed by calculating the difference between two cut-offs (ANA 1:40 and 1:160). A total of 13,233 samples were processed for ANA, of which 59.9% were positive with the 1:40 cut-off and 39.2% with the 1:160 cut-off. At ANA titer 1:40, 0.2% of the samples were anti-ENA-positive and 2.2% were anti-dsDNA positive. Only ANA dilutions of 1:160 and higher showed significantly increased positive predictive value for anti-ENA (1.5 versus 0.2, p=0.029) and anti-dsDNA (8.3 versus 2.2, p<0.001) compared to the 1:40 titer. With the 1:160 cut-off, 16.6% fewer ANA tests, 41.8% fewer anti-ENA determinations and 36.4% fewer anti-dsDNA tests would have been needed. The average saving was 0.87 cost-units per sample (1 unit=2.06euro). We conclude that setting the starting dilution for ANA at 1:160 avoids unnecessary studies, increases the positive predictive values of ANA for anti-ENA and anti-dsDNA, and generates clinical and economic benefits.

  5. Fast proton exchange in histidine: measurement of rate constants through indirect detection by NMR spectroscopy.

    PubMed

    Sehgal, Akansha Ashvani; Duma, Luminita; Bodenhausen, Geoffrey; Pelupessy, Philippe

    2014-05-19

    Owing to its imidazole side chain, histidine participates in various processes such as enzyme catalysis, pH regulation, metal binding, and phosphorylation. The determination of exchange rates of labile protons for such a system is important for understanding its functions. However, these rates are too fast to be measured directly in an aqueous solution by using NMR spectroscopy. We have obtained the exchange rates of the NH3(+) amino protons and the labile NH(ε2) and NH(δ1) protons of the imidazole ring by indirect detection through nitrogen-15 as a function of temperature (272 K

  6. [Comparative study of indirect immunofluorescence (IIF) and ELISA techniques in the detection of parvovirus B19].

    PubMed

    González, M; Hassanhi, M; Rivera, S; Bracho, M P

    2000-03-01

    To determine the seroprevalence of IgG and IgM antibodies against Parvovirus B19 (P. B19), we studied the sera of 53 patients with different hematologic disorders and the sera of 15 controls using indirect immunofluorescence (IFI) and the ELISA method. The prevalence of IgG in the control group was 46.6%, in patients with aplastic crisis was 83.3% (IFI) and 66.7% (ELISA) and, in patients without crisis was 68.9% (IFI) and 72.4% (ELISA). IgM was negative except for patients with crisis: 8.3% (IFI) and 29.1% (ELISA). The higher seroprevalence (IgG) found in patients in comparison with controls might be due to a greater exposure of of patients to the virus. The agreement for both techniques was 81%(IgG) and 93% (IgM) however ELISA technique was more sensitive for detecting IgM of P. B19. In spite of serologic evidence and evaluating a simple serum sample per patient, we could establish an association between aplastic crisis and viral infection for IgM ELISA but not for IgG between hematologic disorders and infection for the P. B19.

  7. AMS-02 positron excess and indirect detection of three-body decaying dark matter

    NASA Astrophysics Data System (ADS)

    Cheng, Hsin-Chia; Huang, Wei-Chih; Huang, Xiaoyuan; Low, Ian; Sming Tsai, Yue-Lin; Yuan, Qiang

    2017-03-01

    We consider indirect detection of meta-stable dark matter particles decaying into a stable neutral particle and a pair of standard model fermions. Due to the softer energy spectra from the three-body decay, such models could potentially explain the AMS-02 positron excess without being constrained by the Fermi-LAT gamma-ray data and the cosmic ray anti-proton measurements. We scrutinize over different final state fermions, paying special attention to handling of the cosmic ray background and including various contributions from cosmic ray propagation with the help of the LIKEDM package. It is found that primary decays into an electron-positron pair and a stable neutral particle could give rise to the AMS-02 positron excess and, at the same time, stay unscathed against the gamma-ray and anti-proton constraints. Decays to a muon pair or a mixed flavor electron-muon pair may also be viable depending on the propagation models. Decays to all other standard model fermions are severely disfavored.

  8. The potential of the dwarf galaxy Triangulum II for dark matter indirect detection

    NASA Astrophysics Data System (ADS)

    Genina, Anna; Fairbairn, Malcolm

    2016-12-01

    The recently discovered object Triangulum II appears to be an ultrafaint dwarf spheroidal galaxy which may be one of the most dark-matter-dominated objects yet known. In this work we try to estimate the potential of this object for studies of the indirect detection of self-annihilating dark matter by obtaining its astrophysical J-factor. We perform a basic estimate of the velocity gradient to look for signs of the halo being tidally disrupted but show that the observed value is statistically compatible with zero velocity gradient. We solve the spherical Jeans equation using Markov chain Monte Carlo engine GreAT and the Jeans analysis part of the CLUMPY package. We find the results point towards a very large J-factor, appearing to make Triangulum II one of the best targets in the search for dark matter. However we stress that the very small number of line of sight velocities currently available for this object make follow-up studies essential.

  9. Determination of the detective quantum efficiency of a prototype, megavoltage indirect detection, active matrix flat-panel imager.

    PubMed

    El-Mohri, Y; Jee, K W; Antonuk, L E; Maolinbay, M; Zhao, Q

    2001-12-01

    After years of aggressive development, active matrix flat-panel imagers (AMFPIs) have recently become commercially available for radiotherapy imaging. In this paper we report on a comprehensive evaluation of the signal and noise performance of a large-area prototype AMFPI specifically developed for this application. The imager is based on an array of 512 x 512 pixels incorporating amorphous silicon photodiodes and thin-film transistors offering a 26 x 26 cm2 active area at a pixel pitch of 508 microm. This indirect detection array was coupled to various x-ray converters consisting of a commercial phosphor screen (Lanex Fast B, Lanex Regular, or Lanex Fine) and a 1 mm thick copper plate. Performance of the imager in terms of measured sensitivity, modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE) is reported at beam energies of 6 and 15 MV and at doses of 1 and 2 monitor units (MU). In addition, calculations of system performance (NPS, DQE) based on cascaded-system formalism were reported and compared to empirical results. In these calculations, the Swank factor and spatial energy distributions of secondary electrons within the converter were modeled by means of EGS4 Monte Carlo simulations. Measured MTFs of the system show a weak dependence on screen type (i.e., thickness), which is partially due to the spreading of secondary radiation. Measured DQE was found to be independent of dose for the Fast B screen, implying that the imager is input-quantum-limited at 1 MU, even at an extended source-to-detector distance of 200 cm. The maximum DQE obtained is around 1%--a limit imposed by the low detection efficiency of the converter. For thinner phosphor screens, the DQE is lower due to their lower detection efficiencies. Finally, for the Fast B screen, good agreement between calculated and measured DQE was observed.

  10. Indirect drive ablative Rayleigh-Taylor experiments with rugby hohlraums on OMEGA

    NASA Astrophysics Data System (ADS)

    Casner, A.; Galmiche, D.; Huser, G.; Jadaud, J.-P.; Liberatore, S.; Vandenboomgaerde, M.

    2009-09-01

    Results of ablative Rayleigh-Taylor instability growth experiments performed in indirect drive on the OMEGA laser facility [T. R. Boehly, D. L. Brown, S. Craxton et al., Opt. Commun. 133, 495 (1997)] are reported. These experiments aim at benchmarking hydrocodes simulations and ablator instabilities growth in conditions relevant to ignition in the framework of the Laser MégaJoule [C. Cavailler, Plasma Phys. Controlled Fusion 47, 389 (2005)]. The modulated samples under study were made of germanium-doped plastic (CHGe), which is the nominal ablator for future ignition experiments. The incident x-ray drive was provided using rugby-shaped hohlraums [M. Vandenboomgaerde, J. Bastian, A. Casner et al., Phys. Rev. Lett. 99, 065004 (2007)] and was characterized by means of absolute time-resolved soft x-ray power measurements through a dedicated diagnostic hole, shock breakout data and one-dimensional and two-dimensional (2D) side-on radiographies. All these independent x-ray drive diagnostics lead to an actual on-foil flux that is about 50% smaller than laser-entrance-hole measurements. The experimentally inferred flux is used to simulate experimental optical depths obtained from face-on radiographies for an extensive set of initial conditions: front-side single-mode (wavelength λ =35, 50, and 70 μm) and two-mode perturbations (wavelength λ =35 and 70 μm, in phase or in opposite phase). Three-dimensional pattern growth is also compared with the 2D case. Finally the case of the feedthrough mechanism is addressed with rear-side modulated foils.

  11. Indirect drive ablative Rayleigh-Taylor experiments with rugby hohlraums on OMEGA

    SciTech Connect

    Casner, A.; Galmiche, D.; Huser, G.; Jadaud, J.-P.; Liberatore, S.; Vandenboomgaerde, M.

    2009-09-15

    Results of ablative Rayleigh-Taylor instability growth experiments performed in indirect drive on the OMEGA laser facility [T. R. Boehly, D. L. Brown, S. Craxton et al., Opt. Commun. 133, 495 (1997)] are reported. These experiments aim at benchmarking hydrocodes simulations and ablator instabilities growth in conditions relevant to ignition in the framework of the Laser MegaJoule [C. Cavailler, Plasma Phys. Controlled Fusion 47, 389 (2005)]. The modulated samples under study were made of germanium-doped plastic (CHGe), which is the nominal ablator for future ignition experiments. The incident x-ray drive was provided using rugby-shaped hohlraums [M. Vandenboomgaerde, J. Bastian, A. Casner et al., Phys. Rev. Lett. 99, 065004 (2007)] and was characterized by means of absolute time-resolved soft x-ray power measurements through a dedicated diagnostic hole, shock breakout data and one-dimensional and two-dimensional (2D) side-on radiographies. All these independent x-ray drive diagnostics lead to an actual on-foil flux that is about 50% smaller than laser-entrance-hole measurements. The experimentally inferred flux is used to simulate experimental optical depths obtained from face-on radiographies for an extensive set of initial conditions: front-side single-mode (wavelength {lambda}=35, 50, and 70 {mu}m) and two-mode perturbations (wavelength {lambda}=35 and 70 {mu}m, in phase or in opposite phase). Three-dimensional pattern growth is also compared with the 2D case. Finally the case of the feedthrough mechanism is addressed with rear-side modulated foils.

  12. SERS detection of indirect viral DNA capture using colloidal gold and methylene blue as a Raman label

    USDA-ARS?s Scientific Manuscript database

    An indirect capture model assay using colloidal Au nanoparticles is demonstrated for surface enhanced Raman scattering (SERS) spectroscopy detection of DNA. The sequence targeted for capture is derived from the West Nile Virus (WNV) RNA genome and was selected on the basis of exhibiting minimal seco...

  13. Optimized beryllium target design for indirectly driven inertial confinement fusion experiments on the National Ignition Facility

    SciTech Connect

    Simakov, Andrei N. Wilson, Douglas C.; Yi, Sunghwan A.; Kline, John L.; Batha, Steven H.; Clark, Daniel S.; Milovich, Jose L.; Salmonson, Jay D.

    2014-02-15

    For indirect drive inertial confinement fusion, Beryllium (Be) ablators offer a number of important advantages as compared with other ablator materials, e.g., plastic and high density carbon. In particular, the low opacity and relatively high density of Be lead to higher rocket efficiencies giving a higher fuel implosion velocity for a given X-ray drive; and to higher ablation velocities providing more ablative stabilization and reducing the effect of hydrodynamic instabilities on the implosion performance. Be ablator advantages provide a larger target design optimization space and can significantly improve the National Ignition Facility (NIF) [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)] ignition margin. Herein, we summarize the Be advantages, briefly review NIF Be target history, and present a modern, optimized, low adiabat, Revision 6 NIF Be target design. This design takes advantage of knowledge gained from recent NIF experiments, including more realistic levels of laser-plasma energy backscatter, degraded hohlraum-capsule coupling, and the presence of cross-beam energy transfer.

  14. Optimized beryllium target design for indirectly driven inertial confinement fusion experiments on the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Simakov, Andrei N.; Wilson, Douglas C.; Yi, Sunghwan A.; Kline, John L.; Clark, Daniel S.; Milovich, Jose L.; Salmonson, Jay D.; Batha, Steven H.

    2014-02-01

    For indirect drive inertial confinement fusion, Beryllium (Be) ablators offer a number of important advantages as compared with other ablator materials, e.g., plastic and high density carbon. In particular, the low opacity and relatively high density of Be lead to higher rocket efficiencies giving a higher fuel implosion velocity for a given X-ray drive; and to higher ablation velocities providing more ablative stabilization and reducing the effect of hydrodynamic instabilities on the implosion performance. Be ablator advantages provide a larger target design optimization space and can significantly improve the National Ignition Facility (NIF) [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)] ignition margin. Herein, we summarize the Be advantages, briefly review NIF Be target history, and present a modern, optimized, low adiabat, Revision 6 NIF Be target design. This design takes advantage of knowledge gained from recent NIF experiments, including more realistic levels of laser-plasma energy backscatter, degraded hohlraum-capsule coupling, and the presence of cross-beam energy transfer.

  15. Optimizing the hohlraum gas density for better symmetry control of indirect drive implosion experiments

    NASA Astrophysics Data System (ADS)

    Izumi, Nobuhiko; Hall, G. N.; Nagel, S. R.; Khan, S.; Rygg, R. R.; MacKinnon, A. J.; Ho, D. D.; Berzak Hopkins, L.; Jones, O. S.; Town, R. P. J.; Bradley, D. K.

    2014-10-01

    To achieve a spherically symmetric implosion, control of drive uniformity is essential. Both the ablation pressure and the mass ablation rate on the capsule surface should be made as uniform as possible for the duration of the drive. For an indirect drive implosion, the drive uniformity changes during the pulse because of: (1) the dynamic movement of the laser spots due to blow-off of the hohlraum wall, and (2) cross-beam energy transfer caused by laser-plasma interaction in the hohlraum. To tamp the wall blow-off, we use gas filled hohlraums. The cross-beam energy transfer can be controlled by applying a wave length separation between the cones of the laser beams. However, both of those dynamic effects are sensitive to the initial density of the hohlraum gas fill. To assess this, we performed implosion experiments with different hohlraum gas densities and tested the effect on drive asymmetry. The uniformity of the acceleration was measured by in-flight x-ray backlit imaging of the capsule. The uniformity of the core assembly was observed by imaging the self emission x-ray from the core. We will report on the experimental results and compare them to hydrodynamic simulations. Prepared by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-626372.

  16. Spin-state selective carbon-detected HNCO with TROSY optimization in all dimensions and double echo-antiecho sensitivity enhancement in both indirect dimensions.

    PubMed

    Hu, Kaifeng; Vögeli, Beat; Clore, G Marius

    2007-05-02

    A carbon-detected TROSY-optimized experiment correlating 1HN, 15N, and 13C' resonances, referred to as c-TROSY-HNCO is presented, in which the 1HN and 15N TROSY effects are maintained in both indirect dimensions, while the directly detected 13C' is doubly TROSY-optimized with respect to 1HN and 15N. A new strategy for sensitivity enhancement, the so-called double echo-antiecho (dEA), is described and implemented in the c-TROSY-HNCO experiment. dEA offers sensitivity enhancement of square root of 2 in both indirect dimensions and is generally applicable to many multidimensional experiments. A carbon-detected HNCO experiment, c-HNCO, without TROSY optimization and sensitivity enhancement is also designed for comparison purposes. Relaxation simulations show that for a protein with a rotational correlation time of 10 ns or larger, the c-TROSY-HNCO experiment displays comparable or higher signal-to-noise (S/N) ratios than the c-HNCO experiment, although the former selects only 1/4 of the initial magnetization relative to the later. The high resolution afforded in the directly detected carbon dimension allows direct measurement of the doublet splitting to extract 1JCalphaC' scalar and 1DCalphaC' residual dipolar couplings. Simulations indicate that the c-TROSY-HNCO experiment offers higher precision (lower uncertainty) compared to the c-HNCO experiment for larger proteins. The experiments are applied to 15N/13C/2H/[Leu,Val]-methyl-protonated IIBMannose, a protein of molecular mass 18.6 kDa with a correlation time of approximately 10 ns at 30 degrees C. The experimental pairwise root-mean-square deviation for the measured 1JCalphaC' couplings obtained from duplicate experiments is 0.77 Hz. By directly measuring the doublet splitting, the experiments described here are expected to be much more tolerant to nonuniform values of 1JCalphaC' (or 1JCalphaC' + 1DCalphaC' for aligned samples) and pulse imperfections due to the smaller number of applied pulses in the "out

  17. [Rapid determination of cyclamate in foods by capillary zone electrophoresis with indirect ultraviolet detection].

    PubMed

    Chen, Tong; Ding, Xiaojing; Li, Yizheng; Zhao, Xudong; Zhao, Shan

    2014-06-01

    A new method for the rapid determination of cyclamate in foods by capillary zone electrophoresis (CZE) with indirect ultraviolet detection was developed. The separation was carried out with an uncoated fused-silica capillary (75 microm i.d., total length 80 cm, effective length 70 cm). The separation buffer consisted of 2 mmol/L sodium benzoate, 10 mmol/L sodium carbonate and 0.5 mmol/L hexadecyl trimethyl ammonium bromide. The separation voltage was -30 kV and the detection wavelength was 200 nm. The liquid samples could be directly injected after dilution with ultrapure water. The solid samples were first grounded or cut into pieces, and then extracted with ultrapure water. Then, the mixed solution was centrifuged. The supernatant was directly injected or injected after dilution with ultrapure water. The analytes were determined by external calibration. The limits of detection (S/N = 3) and the limits of quantification (S/N = 9) were 8.9 mg/kg and 26.7 mg/kg, respectively. The linear range between the corrected peak area and the mass concentration was from 1.2 mg/L to 80 mg/L with the correlation coefficient of 0.999 9. The average spiked recoveries of five replicates at three spiked levels (2.5, 10 and 20 mg/L) were 93.4%, 100.3% and 101.9% with the relative standard deviations of 6.7%, 2.0% and 2.2%, respectively. The intra- and inter-day precisions of the method were 2.6% and 4.5%, respectively. The method is simple and rapid with minimal sample pretreatment and reagent consumption. No solvent was needed throughout the whole process of analysis. The analysis could be completed within 11 min (6 min for rinsing and 5 min for separation). The newly established method was used for the determination of cyclamate in a proficiency test sample. The results were in good agreement with that of the National Standard method, which illustrated the accuracy of the present method. Then, seven food samples were analyzed using the current new method and satisfactory results

  18. [Indirect UV detection of short chain carboxylic acids in oil field water by high performance capillary zone electrophoresis].

    PubMed

    Liu, C; Ma, T; Fang, X; Mei, B

    1997-03-01

    Short chain carboxylic acids are the major aqueous organic species in oil field water. It is considered that they play an important role in the geochemical evolution of second porosity in oil reservoir. In this paper, short chain carboxylic acid anions were analyzed by HP(3D)CE high performance capillary electrophoresis system (Hewlett-Packard, Germany) with a buffer system of dinitrobenzoic acid-hexadecyltrimethyl ammonium bromide (CTAB). The influence of buffer pH and the concentrations of electrolyte, surfactant and methanol on the seperation of short chain carboxylic acids have been studied. The results showed that the best separation of short chain carboxylic acids could be done with the buffer of 10mmol/L dinitrobenzoic acid, 0.5mmol/L CTAB and 5% methanol at pH=9. Separations were performed in a 50cm x 50microm i.d. fused silica capillary (effective length 48.5cm) at 25 degrees C. A negative potential of 30kV was used for each experiment. Sample was introduced into the capillary by pressure at 50kPa for 10s. Indirect UV detection was operated at 254nm and reference wavelength at 380nm for all experiments. Negative peak was changed into positive one by exchanging between detection wavelength and reference wavelength. Capillary was rinsed for 10min with 0.1mol/L sodium hydroxide and buffer solution before each run. Oil field water was injected directly after filtered through 0.45microm membrane. The result was satisfactory.

  19. Indirect-detection single-photon-counting x-ray detector for breast tomosynthesis

    NASA Astrophysics Data System (ADS)

    Jiang, Hao; Kaercher, Joerg; Durst, Roger

    2016-03-01

    X-ray mammography is a crucial screening tool for early identification of breast cancer. However, the overlap of anatomical features present in projection images often complicates the task of correctly identifying suspicious masses. As a result, there has been increasing interest in acquisition of volumetric information through digital breast tomosynthesis (DBT) which, compared to mammography, offers the advantage of depth information. Since DBT requires acquisition of many projection images, it is desirable that the noise in each projection image be dominated by the statistical noise of the incident x-ray quanta and not by the additive noise of the imaging system (referred to as quantum-limited imaging) and that the cumulative dose be as low as possible (e.g., no more than for a mammogram). Unfortunately, the electronic noise (~2000 electrons) present in current DBT systems based on active matrix, flat-panel imagers (AMFPIs) is still relatively high compared with modest x-ray gain of the a-Se and CsI:Tl x-ray converters often used. To overcome the modest signal-to-noise ratio (SNR) limitations of current DBT systems, we have developed a large-area x-ray imaging detector with the combination of an extremely low noise (~20 electrons) active-pixel CMOS and a specially designed high resolution scintillator. The high sensitivity and low noise of such system provides better SNR by at least an order of magnitude than current state-of-art AMFPI systems and enables x-ray indirect-detection single photon counting (SPC) at mammographic energies with the potential of dose reduction.

  20. Application of photostable quantum dots for indirect immunofluorescent detection of specific bacterial serotypes on small marine animals

    NASA Astrophysics Data System (ADS)

    Decho, Alan W.; Beckman, Erin M.; Chandler, G. Thomas; Kawaguchi, Tomohiro

    2008-06-01

    An indirect immunofluorescence approach was developed using semiconductor quantum dot nanocrystals to label and detect a specific bacterial serotype of the bacterial human pathogen Vibrio parahaemolyticus, attached to small marine animals (i.e. benthic harpacticoid copepods), which are suspected pathogen carriers. This photostable labeling method using nanotechnology will potentially allow specific serotypes of other bacterial pathogens to be detected with high sensitivity in a range of systems, and can be easily applied for sensitive detection to other Vibrio species such as Vibrio cholerae.

  1. Power Doppler imaging in detection of surgically induced indirect neoangiogenesis in adult moyamoya disease.

    PubMed

    Perren, Fabienne; Horn, Peter; Vajkoczy, Peter; Schmiedek, Peter; Meairs, Stephen

    2005-11-01

    Moyamoya is a rare, chronic disease that leads to the progressive narrowing and/or occlusion of the distal internal carotid and proximal cerebral arteries. Chronic cerebral ischemia ensues due to insufficient collateral blood supply. One potential treatment consists of the restoration of regional cerebral blood flow by direct or indirect revascularization surgery. The extent of neovascularization, especially in indirect procedures such as encephalomyosynangiosis (EMS), is currently evaluated with conventional angiography. Because this method is invasive and carries some risks, the authors investigated power Doppler imaging as an alternative noninvasive bedside procedure that can be used to assess surgically induced indirect revascularization in adult patients with moyamoya disease. Twelve symptomatic patients with adult moyamoya disease (seven women and five men, mean age 38 +/- 17 years) underwent combined (direct and indirect) revascularization. They were then examined using conventional angiography and power Doppler imaging to assess the extent of revascularization within 120 days postsurgery. According to the number of intracranial vessels demonstrating opacification on conventional angiography and power Doppler imaging studies, EMS was graded as follows: 1, absent (0 vessels); 2, moderate (one-four vessels); and 3, extensive (> four vessels) for both methods. Examiners were blinded to the classification results for the procedure that they did not grade. All 24 hemispheres were examined. The visual grading of EMS revealed a highly significant agreement between conventional angiography and power Doppler imaging (Spearman rank coefficient, r = 0.92; p < 0.001) and there was 100% agreement of patency of the bypass between the direct and indirect methods. The authors found excellent agreement between the two methods. Therefore, power Doppler imaging is a valid noninvasive alternative to carotid artery angiography in evaluating direct and indirect revascularization.

  2. Separation and detection of VX and its methylphosphonic acid degradation products on a microchip using indirect laser-induced fluorescence.

    PubMed

    Heleg-Shabtai, Vered; Gratziany, Natzach; Liron, Zvi

    2006-05-01

    The application of indirect LIF (IDLIF) technique for on-chip electrophoretic separation and detection of the nerve agent O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothiolate (VX) and its major phosphonic degradation products, ethyl methylphosphonic acid (EMPA) and methylphosphonic acid (MPA) was demonstrated. Separation and detection of MPA degradation products of VX and the nerve agent isopropyl methylphosphonofluoridate (GB) are presented. The negatively charged dye eosin was found to be a good fluorescent marker for both the negatively charged phosphonic acids and the positively charged VX, and was chosen as the IDLIF visualization fluorescent dye. Separation and detection of VX, EMPA, and MPA in a simple-cross microchip were completed within less than a minute, and consumed only a 50 pL sample volume. A characteristic system peak that appeared in all IDLIF electropherograms served as an internal standard that increased the reliability of peak identification. The negative peak of both VX and the MPAs is in agreement with indirect detection theory and with previous reports in the literature. The LOD of VX and EMPA by IDLIF was 30 and 37 microM, respectively. Despite the fact that the detection sensitivity is relatively low, the rapid simultaneous on-chip analysis of both VX and its degradation products as well as the separation and detection of the MPA degradation products of both VX and GB, increases detection reliability and may present a choice when sensitivity is not critical compared with speed and simplicity of the assay.

  3. The Influence of Direct and Indirect Juvenile Victimization Experiences on Adult Victimization and Fear of Crime.

    PubMed

    Grubb, Jonathan A; Bouffard, Leana A

    2015-11-01

    Research has identified that juvenile victimization can play a detrimental role for individuals later in life. While this literature has focused on direct and indirect forms of victimization at different stages of life, the influence of juvenile victimization on fear of crime and violent victimization as an adult has been limited. To expand this body of literature, the present research examines the effects of direct (sexual victimization) and indirect (witnessing parental intimate partner violence) juvenile victimization on fear of crime as well as the prevalence of victimization as an adult. Using telephone survey data collected from randomly selected Texas adults, this study demonstrates that both juvenile sexual victimization and indirect victimization increase the likelihood of adult victimization, whereas juvenile sexual victimization increases the likelihood of adult sexual victimization. In contrast, fear of crime as an adult was not significantly influenced by either juvenile sexual victimization or indirect victimization. A discussion of how these findings relate to previous research, limitations, and implications are also provided. © The Author(s) 2014.

  4. Flight experience with windshear detection

    NASA Technical Reports Server (NTRS)

    Zweifel, Terry

    1990-01-01

    Windshear alerts resulting from the Honeywell Windshear Detection and Guidance System are presented based on data from approximately 248,000 revenue flights at Piedmont Airlines. The data indicate that the detection system provides a significant benefit to the flight crew of the aircraft. In addition, nuisance and false alerts were found to occur at an acceptably low rate to maintain flight crew confidence in the system. Data from a digital flight recorder is also presented which shows the maximum and minimum windshear magnitudes recorded for a representative number of flights in February, 1987. The effect of the boundary layer of a steady state wind is also discussed.

  5. Indirect UV detection-ion-exclusion/cation-exchange chromatography of common inorganic ions with sulfosalicylic acid eluent.

    PubMed

    Kozaki, Daisuke; Mori, Masanobu; Nakatani, Nobutake; Arai, Kaori; Masuno, Tomoe; Koseki, Masakazu; Itabashi, Hideyuki; Tanaka, Kazuhiko

    2013-01-01

    Herein, we describe indirect UV detection-ion-exclusion/cation-exchange chromatography (IEC/CEC) on a weakly acidic cation-exchange resin in the H(+)-form (TSKgel Super IC-A/C) using sulfosalicylic acid as the eluent. The goal of the study was to characterize the peaks detected by UV detector. The peak directions of analyte ions in UV at 315 nm were negative because the molar absorbance coefficients of analyte anions and cations were lower than that of the sulfosalicylic acid eluent. Good chromatographic resolution and high signal-to-noise ratios of analyte ions were obtained for the separations performed using 1.1 mM sulfosalicylic acid and 1.5 mM 18-crown-6 as the eluent. The relative standard deviations (RSDs) of the peak areas ranged from 0.6 to 4.9%. Lower detection limits of the analytes were achieved using indirect UV detection at 315 nm (0.23 - 0.98 μM) than those obtained with conductometric detection (CD) (0.61 - 2.1 μM) under the optimized elution conditions. The calibration curves were linear in the range from 0.01 to 1.0 mM except for Cl(-), which was from 0.02 to 2.0 mM. The present method was successfully applied to determine common inorganic ions in a pond water sample.

  6. Impedance match equation of state experiments using indirectly laser-driven multimegabar shocks

    NASA Astrophysics Data System (ADS)

    Rothman, S. D.; Evans, A. M.; Horsfield, C. J.; Graham, P.; Thomas, B. R.

    2002-05-01

    Measurements of equation of state (EOS) points on the principal Hugoniots of Cu, Au, Pb and the plastics Parylene-C and brominated CH at multimegabar pressures have been made using the 1 TW HELEN laser at AWE. The aim was 1% accuracy in shock velocity measurement (3%-4% in pressure) in order to compare with data from gas-gun and nuclear underground test experiments and the theoretical EOS's based on, or supported by, these data. Experiments comprised a hohlraum heated by two 500 J, 0.53 μm wavelength, 1 ns Gaussian laser pulses generating an x-ray flux which drove a shock into a target consisting of a base, with steps of a known EOS material and of the material of unknown EOS. Shock breakout from base and steps was detected by monitoring light emission from the target with optical streak cameras and shock velocities were derived from the transit times across the known-height steps.

  7. [Expression of prn gene of Bordetella bronchiseptica and development of a recombinant protein-based indirect ELISA for antibodies detection].

    PubMed

    Zhao, Zhanqin; Xue, Yun; Wu, Bin; Tang, Xibiao; Chen, Huanchun; Li, Zengqiang; Hu, Ruiming; Zhang, Jianmin; Duan, Longchuan

    2008-03-01

    We developed an indirect ELISA method for detecting Bordetella bronchiseptica (Bb) pertactin antibodies based on the recombinant pertactin protein expressed in Escherichia coli (DE3) strain. The prn gene encoding Bb pertactin was fused to the downstream of glutathione S-transferase (GST) of pGEX-KG expression vector, resulting in the fusion expression plasmid pGEX-prn. SDS-PAGE showed that the GST-PRN fusion protein was expressed in high level in BL21 carrying pGEX-prn. The strong reactivity of the GST-PRN fusion protein, specifically with antiserum against porcine Bordetellosis caused by Bb HH0809, was identified by Western blot. The recombinant protein fragment of rPRN was purified from the GST-PRN fusion protein digested by protease thrombin with the purity of 93.1%. The rPRN-based indirect ELISA was developed for detecting antibodies against PRN. The ELISA could detect positive samples in experimentally infected pigs fourteen days post inoculation and the degree of sensitivity was over 4 times higher than the latex agglutination test with the coating antigen of killed Bb. Thirty-two point seven percent of positive samples were detected in 1,229 clinical samples while no false positive results were found in detecting 7 antisera against porcine bacterial diseases. Sera samples from two bordetellosis-positive pig fields were tested by the indirect ELISA method and the results indicated that pigs were infected by Bb during the nursery periods. The assay showed excellent specificity, sensitivity and reduplication, and can be useful for epidemiological survey and clinical diagnosis of swine bordetellosis.

  8. Lateralized direct and indirect semantic priming effects in subjects with paranormal experiences and beliefs.

    PubMed

    Pizzagalli, D; Lehmann, D; Brugger, P

    2001-01-01

    The present investigation tested the hypothesis that, as an aspect of schizotypal thinking, the formation of paranormal beliefs was related to spreading activation characteristics within semantic networks. From a larger student population (n = 117) prescreened for paranormal belief, 12 strong believers and 12 strong disbelievers (all women) were invited for a lateralized semantic priming task with directly and indirectly related prime-target pairs. Believers showed stronger indirect (but not direct) semantic priming effects than disbelievers after left (but not right) visual field stimulation, indicating faster appreciation of distant semantic relations specifically by the right hemisphere, reportedly specialized in coarse rather than focused semantic processing. These results are discussed in the light of recent findings in schizophrenic patients with thought disorders. They suggest that a disinhibition with semantic networks may underlie the formation of paranormal belief. The potential usefulness of work with healthy subjects for neuropsychiatric research is stressed.

  9. Sensitive detection of surface- and size-dependent direct and indirect band gap transitions in ferritin.

    PubMed

    Colton, J S; Erickson, S D; Smith, T J; Watt, R K

    2014-04-04

    Ferritin is a protein nano-cage that encapsulates minerals inside an 8 nm cavity. Previous band gap measurements on the native mineral, ferrihydrite, have reported gaps as low as 1.0 eV and as high as 2.5-3.5 eV. To resolve this discrepancy we have used optical absorption spectroscopy, a well-established technique for measuring both direct and indirect band gaps. Our studies included controls on the protein nano-cage, ferritin with the native ferrihydrite mineral, and ferritin with reconstituted ferrihydrite cores of different sizes. We report measurements of an indirect band gap for native ferritin of 2.140 ± 0.015 eV (579.7 nm), with a direct transition appearing at 3.053 ± 0.005 eV (406.1 nm). We also see evidence of a defect-related state having a binding energy of 0.220 ± 0.010 eV . Reconstituted ferrihydrite minerals of different sizes were also studied and showed band gap energies which increased with decreasing size due to quantum confinement effects. Molecules that interact with the surface of the mineral core also demonstrated a small influence following trends in ligand field theory, altering the native mineral's band gap up to 0.035 eV.

  10. Model-independent indirect detection constraints on hidden sector dark matter

    NASA Astrophysics Data System (ADS)

    Elor, Gilly; Rodd, Nicholas L.; Slatyer, Tracy R.; Xue, Wei

    2016-06-01

    If dark matter inhabits an expanded ``hidden sector'', annihilations may proceed through sequential decays or multi-body final states. We map out the potential signals and current constraints on such a framework in indirect searches, using a model-independent setup based on multi-step hierarchical cascade decays. While remaining agnostic to the details of the hidden sector model, our framework captures the generic broadening of the spectrum of secondary particles (photons, neutrinos, e+e- and bar p p) relative to the case of direct annihilation to Standard Model particles. We explore how indirect constraints on dark matter annihilation limit the parameter space for such cascade/multi-particle decays. We investigate limits from the cosmic microwave background by Planck, the Fermi measurement of photons from the dwarf galaxies, and positron data from AMS-02. The presence of a hidden sector can change the constraints on the dark matter by up to an order of magnitude in either direction (although the effect can be much smaller). We find that generally the bound from the Fermi dwarfs is most constraining for annihilations to photon-rich final states, while AMS-02 is most constraining for electron and muon final states; however in certain instances the CMB bounds overtake both, due to their approximate independence on the details of the hidden sector cascade. We provide the full set of cascade spectra considered here as publicly available code with examples at http://web.mit.edu/lns/research/CascadeSpectra.html.

  11. Optical detection of magnetoplasma resonances in indirect-gap AlAs/AlGaAs quantum wells

    NASA Astrophysics Data System (ADS)

    Khisameeva, A. R.; Gubarev, S. I.; Murav'ev, V. M.; Kukushkin, I. V.

    2017-07-01

    Magnetoplasma excitations in AlAs/AlGaAs quantum wells, characterized by strong anisotropy in the effective mass of two-dimensional electrons, are investigated using the optical detection of resonance microwave absorption. This technique is used for the first time for an indirect-gap semiconductor. It is found that the magnetic dispersion of the cyclotron magnetoplasma mode deviates significantly from the theoretically expected behavior. This may be related to the considerably more pronounced manifestation of retardation effects in two-dimensional systems with an anisotropic energy spectrum.

  12. Femoro-acetabular impingement: can indirect MR arthrography be considered a valid method to detect endoarticular damage? A preliminary study.

    PubMed

    Pozzi, Grazia; Stradiotti, Paola; Parra, Cleber Garcia; Zagra, Luigi; Sironi, Sandro; Zerbi, Alberto

    2009-01-01

    To assess the effectiveness of indirect Magnetic Resonance arthrography (i-MRa) in the detection of chondral and labral lesions related to femoro-acetabular impingement (FAI) a series of 21 hip joints in 17 patients with a clinical diagnosis of FAI were examined either with standard MR imaging, i-MRa and direct-MR arthrography (d-MRa). Sensitivity and accuracy of i-MRa in detecting chondral, labral and tardive lesions were calculated and compared with standard MR. The agreement in detecting endoarticular damage between i-MRa and d-MRa and the interobserver agreement was assessed by K statistic (p<0.05). Finally the presence of trocanteric bursitis was evaluated. I-MRa showed higher values of both sensivity and accuracy than standard MR in detecting chondral damage, with an increase to 92% for the first item and 95% for the second. The same was noticed in labrum evaluation with an increase to 88% and 90% respectively. The level of agreement between i-MRa and d-MRa in detection of chondral lesions was excellent, substantial for the labral damage and absolute for early osteoarthritic changes. An excellent interobserver agreement resulted in detection of both chondral and labral damages with i-MRa. In 6 hips (28,5%) we also found the presence of peri-trochanteric soft tissue inflammation that indicated the possibility of extrarticular involvement in FAI. Indirect-MRa can be considered a valid method of assessing endoarticular damage related to FAI, in comparison to d-MRa. It should be performed instead of standard MR if d-MRa is not available.

  13. Advantages of an indirect semiconductor quantum well system for infrared detection

    NASA Technical Reports Server (NTRS)

    Yang, Chan-Lon; Somoano, Robert; Pan, Dee-Son

    1989-01-01

    The infrared intersubband absorption process in quantum well systems with anisotropic bulk effective masses, which usually occurs in indirect semiconductors was analyzed. It is found that the anisotropic effective mass can be utilized to provide allowed intersubband transitions at normal incidence to the quantum well growth direction. This transition is known to be forbidden for cases of isotropic effective mass. This property can be exploited for infrared sensor application of quantum well structures by allowing direct illumination of large surface areas without using special waveguide structures. The 10-micron intersubband absorption in quantum wells made of the silicon-based system Si/Si(1-x)Ge(x) was calculated. It is found that it is readily possible to achieve an absorption constant of the order of 10,000/cm in these Si quantum wells with current doping technology.

  14. Model-independent indirect detection constraints on hidden sector dark matter

    SciTech Connect

    Elor, Gilly; Rodd, Nicholas L.; Slatyer, Tracy R.; Xue, Wei

    2016-06-10

    If dark matter inhabits an expanded “hidden sector”, annihilations may proceed through sequential decays or multi-body final states. We map out the potential signals and current constraints on such a framework in indirect searches, using a model-independent setup based on multi-step hierarchical cascade decays. While remaining agnostic to the details of the hidden sector model, our framework captures the generic broadening of the spectrum of secondary particles (photons, neutrinos, e{sup +}e{sup −} and p-barp) relative to the case of direct annihilation to Standard Model particles. We explore how indirect constraints on dark matter annihilation limit the parameter space for such cascade/multi-particle decays. We investigate limits from the cosmic microwave background by Planck, the Fermi measurement of photons from the dwarf galaxies, and positron data from AMS-02. The presence of a hidden sector can change the constraints on the dark matter by up to an order of magnitude in either direction (although the effect can be much smaller). We find that generally the bound from the Fermi dwarfs is most constraining for annihilations to photon-rich final states, while AMS-02 is most constraining for electron and muon final states; however in certain instances the CMB bounds overtake both, due to their approximate independence on the details of the hidden sector cascade. We provide the full set of cascade spectra considered here as publicly available code with examples at http://web.mit.edu/lns/research/CascadeSpectra.html.

  15. Evaluation of an In-house indirect ELISA for detection of antibody against haemorrhagic septicemia in Asian elephants.

    PubMed

    Tankaew, Pallop; Singh-La, Thawatchai; Titaram, Chatchote; Punyapornwittaya, Veerasak; Vongchan, Preeyanat; Sawada, Takuo; Sthitmatee, Nattawooti

    2017-03-01

    Pasteurella multocida causes haemorrhagic septicemia in livestock and wild animals, including elephants. The disease has been reported in Asian elephants in India and Sri Lanka, but to date there have been no reported cases in Thailand. ELISA or indirect hemagglutination assays (IHA) have been demonstrated to be able to detect the antibody against the disease in cattle, but no data are available for elephants. The present study reports a novel in-house indirect ELISA for antibody detection of haemorrhagic septicemia in Asian elephants, and evaluates the sensitivity and specificity of the method using a Bayesian approach. The characteristics of ELISA and IHA were analyzed using a one population Bayesian model assuming conditional dependence between these two diagnostic tests. The IHA was performed as recommended by the World Organization for Animal Health (OIE) manual for haemorrhagic septicemia. An in-house indirect ELISA was developed with a heat extract antigen of P. multocida strain M-1404 (serovar B:2) as a coating antigen and rabbit anti-immunoglobulin G conjugated with horseradish peroxidase (eIgG-HRP). The checkerboard titration method was done using elephant sera immunized with P. multocida bacterin and negative sera from colostrum-deprived elephant calves. The concentrations of heat extract antigen (160μg/ml), sample serum (1:100), and eIgG-HRP (1:1000) were optimal for the assay. The calculated cut-off value was 0.103. Of the elephant sera, 50.59% (43/85) were considered seropositive by ELISA. The sensitivity of the ELISA test was higher than that of the IHA test [median=86.5%, 95% posterior probability interval (PPI)=52.5-98.9%] while the specificity was lower (median=54.1%, PPI=43.6-64.7%). The median sensitivity and specificity of IHA were 80.5% (PPI=43.8-98.0%) and 78.4% (PPI=69.0-87.0%), respectively. These findings suggest that our in-house indirect ELISA can be used as a tool to detect the antibody against haemorrhagic septicemia in Asian

  16. New preconditioning strategy for the determination of inorganic anions with capillary zone electrophoresis using indirect UV detection.

    PubMed

    Raber, G; Greschonig, H

    2000-08-25

    It is widely accepted that preconditioning procedures are indispensable in capillary electrophoresis in order to achieve reproducibility of migration times and peak areas. Several preconditioning strategies have been employed for electrophoretic determinations of inorganic anions using indirect UV detection including simple flushing with buffer or alkaline or acid pre-rinsing followed by flushing with electrolyte. We investigated the influence of various preconditioning strategies on the reproducibility of migration times and peak areas of inorganic anions. The electrolyte systems for indirect UV detection were based on pyromellitic acid and chromic acid respectively as UV absorbing probes and hexamethonium hydroxide as electroosmatic flow modifier. Preconditioning agents under investigation were electrolyte buffer, NaOH, HCl and the free acids of the UV absorbing probes. Investigations showed that reproducibility of migration times and peak areas can be significantly improved by acid pre-rinsing using the corresponding acid of the UV absorbing probes compared to preconditioning by flushing the capillary with buffer. In contrast to acid pre-rinsing using hydrochloric acid no interfering signals within the migration time window of inorganic anions under investigation can be observed. The optimized preconditioning procedure yields relative standard deviations of migration times less than 0.25% (n = 10). Relative standard deviations of corrected peak areas were below 5% applying acid preconditioning using pyromellitic acid.

  17. Detection of Ganoderic Acid A in Ganoderma lingzhi by an Indirect Competitive Enzyme-Linked Immunosorbent Assay.

    PubMed

    Sakamoto, Seiichi; Kohno, Toshitaka; Shimizu, Kuniyoshi; Tanaka, Hiroyuki; Morimoto, Satoshi

    2016-05-01

    Ganoderma is a genus of medicinal mushroom traditionally used for treating various diseases. Ganoderic acid A is one of the major bioactive Ganoderma triterpenoids isolated from Ganoderma species. Herein, we produced a highly specific monoclonal antibody against ganoderic acid A (MAb 12 A) and developed an indirect competitive ELISA for the highly sensitive detection of ganoderic acid A in Ganoderma lingzhi, with a limit of detection of 6.10 ng/mL. Several validation analyses support the accuracy and reliability of the developed indirect competitive ELISA for use in the quality control of Ganoderma based on ganoderic acid A content. Furthermore, quantitative analysis of ganoderic acid A in G. lingzhi revealed that the pileus exhibits the highest ganoderic acid A content compared with the stipe and spore of the fruiting body; the best extraction efficiency was found when 50 % ethanol was used, which suggests the use of a strong liquor to completely harness the potential of Ganoderma triterpenoids in daily life. Georg Thieme Verlag KG Stuttgart · New York.

  18. Detection of Schistosoma mansoni Antibodies in a Low-Endemicity Area Using Indirect Immunofluorescence and Circumoval Precipitin Test

    PubMed Central

    Carvalho do Espírito-Santo, Maria Cristina; Pinto, Pedro Luiz; Gargioni, Cybele; Viviana Alvarado-Mora, Monica; Pagliusi Castilho, Vera Lúcia; Pinho, João Ranato Rebello; de Albuquerque Luna, Expedito José; Borges Gryschek, Ronaldo Cesar

    2014-01-01

    Parasitological diagnostic methods for schistosomiasis lack sensitivity, especially in regions of low endemicity. The objective of this study was to determine the prevalence of Schistosoma mansoni infections by antibody detection using the indirect immunofluorescence assay (IFA-IgM) and circumoval precipitin test (COPT). Serum samples of 572 individuals were randomly selected. The IFA-IgM and COPT were used to detect anti-S. mansoni antibodies. Of the patients studied, 15.9% (N = 91) were IFA-IgM positive and 5.1% (N = 29) had COPT reactions (P < 0.001 by McNemar's test). Immunodiagnostic techniques showed higher infection prevalence than had been previously estimated. This study suggests that combined use of these diagnostic tools could be useful for the diagnosis of schistosomiasis in epidemiological studies in areas of low endemicity. PMID:24639303

  19. Rapid differentiation of commercial juices and blends by using sugar profiles obtained by capillary zone electrophoresis with indirect UV detection.

    PubMed

    Navarro-Pascual-Ahuir, María; Lerma-García, María Jesús; Simó-Alfonso, Ernesto F; Herrero-Martínez, José Manuel

    2015-03-18

    A method for the determination of sugars in several fruit juices and nectars by capillary zone electrophoresis with indirect UV-vis detection has been developed. Under optimal conditions, commercial fruit juices and nectars from several fruits were analyzed, and the sugar and cyclamate contents were quantified in less than 6 min. A study for the detection of blends of high-value juices (orange and pineapple) with cheaper alternatives was also developed. For this purpose, different chemometric techniques, based on sugar content ratios, were applied. Linear discriminant analysis showed that fruit juices can be distinguished according to the fruit type, juice blends also being differentiated. Multiple linear regression models were also constructed to predict the adulteration of orange and pineapple juices with grape juice. This simple and reliable methodology provides a rapid analysis of fruit juices of economic importance, which is relevant for quality control purposes in food industries and regulatory agencies.

  20. The density of dark matter in the Galactic bulge and implications for indirect detection

    SciTech Connect

    Hooper, Dan

    2016-11-29

    A recent study, making use of the number of horizontal branch stars observed in infrared photometric surveys and kinematic measurements of M-giant stars from the BRAVA survey, combined with N-body simulations of stellar populations, has presented a new determination of the dark matter mass within the bulge-bar region of the Milky Way. That study constrains the total mass within the $\\pm 2.2 \\times \\pm 1.4 \\times \\pm 1.2$ kpc volume of the bulge-bar region to be ($1.84 \\pm 0.07) \\times 10^{10} \\, M_{\\odot}$, of which 9-30% is made up of dark matter. Here, we use this result to constrain the the Milky Way's dark matter density profile, and discuss the implications for indirect dark matter searches. Furthermore uncertainties remain significant, these results favor dark matter distributions with a cusped density profile. For example, for a scale radius of 20 kpc and a local dark matter density of 0.4 GeV/cm$^3$, density profiles with an inner slope of 0.69 to 1.40 are favored, approximately centered around the standard NFW value. In contrast, profiles with large flat-density cores are disfavored by this information.

  1. The density of dark matter in the Galactic bulge and implications for indirect detection

    DOE PAGES

    Hooper, Dan

    2016-11-29

    A recent study, making use of the number of horizontal branch stars observed in infrared photometric surveys and kinematic measurements of M-giant stars from the BRAVA survey, combined with N-body simulations of stellar populations, has presented a new determination of the dark matter mass within the bulge-bar region of the Milky Way. That study constrains the total mass within themore » $$\\pm 2.2 \\times \\pm 1.4 \\times \\pm 1.2$$ kpc volume of the bulge-bar region to be ($$1.84 \\pm 0.07) \\times 10^{10} \\, M_{\\odot}$$, of which 9-30% is made up of dark matter. Here, we use this result to constrain the the Milky Way's dark matter density profile, and discuss the implications for indirect dark matter searches. Furthermore uncertainties remain significant, these results favor dark matter distributions with a cusped density profile. For example, for a scale radius of 20 kpc and a local dark matter density of 0.4 GeV/cm$^3$, density profiles with an inner slope of 0.69 to 1.40 are favored, approximately centered around the standard NFW value. In contrast, profiles with large flat-density cores are disfavored by this information.« less

  2. The Density of Dark Matter in the Galactic Bulge and Implications for Indirect Detection

    SciTech Connect

    Hooper, Dan

    2016-07-29

    A recent study, making use of the number of horizontal branch stars observed in infrared photometric surveys and kinematic measurements of M-giant stars from the BRAVA survey, combined with N-body simulations of stellar populations, has presented a new determination of the dark matter mass within the bulge-bar region of the Milky Way. That study constrains the total mass within the $\\pm 2.2 \\times \\pm 1.4 \\times \\pm 1.2$ kpc volume of the bulge-bar region to be ($1.84 \\pm 0.07) \\times 10^{10} \\, M_{\\odot}$, of which 9-30% is made up of dark matter. Here, we use this result to constrain the the Milky Way's dark matter density profile, and discuss the implications for indirect dark matter searches. Although uncertainties remain significant, these results favor dark matter distributions with a cusped density profile. For example, for a scale radius of 20 kpc and a local dark matter density of 0.4 GeV/cm$^3$, density profiles with an inner slope of 0.69 to 1.40 are favored, approximately centered around the standard NFW value. In contrast, profiles with large flat-density cores are disfavored by this information.

  3. The density of dark matter in the Galactic bulge and implications for indirect detection

    NASA Astrophysics Data System (ADS)

    Hooper, Dan

    2017-03-01

    A recent study by Portail et al., which made use of the number of horizontal branch stars observed in infrared photometric surveys and kinematic measurements of M-giant stars from the BRAVA survey combined with N-body simulations of stellar populations, has presented a new determination of the dark matter mass within the bulge-bar region of the Milky Way. That study constrains the total mass within the ± 2 . 2 × ± 1 . 4 × ± 1 . 2 kpc volume of the bulge-bar region to be (1 . 84 ± 0 . 07) × 1010M⊙, of which 9%-30% is made up of dark matter. Here, we use this result to constrain the Milky Way's dark matter density profile, and discuss the implications for indirect dark matter searches. Although uncertainties remain significant, these results are consistent with and generally favor dark matter distributions with a cusped density profile. For example, for a scale radius of 20 kpc and a local dark matter density of 0.4 GeV/cm3, density profiles with an inner slope of 0.69 to 1.40 are favored, approximately centered around the standard NFW value. In contrast, profiles with large (multi-kiloparsec) flat-density cores are disfavored by this information.

  4. Evaluation of indirect biomarkers for detecting corticosteroids used as illegal growth promoters in beef cattle.

    PubMed

    Vascellari, M; Pozza, G; Poppi, L; Capello, K; Angeletti, R; Ravarotto, L; Andrighetto, I; Mutinelli, F

    2008-08-02

    The histological status of the thymus, blood cortisol concentration and circulating neutrophil:lymphocyte ratio were evaluated in 349 slaughtered beef cattle, to assess the potential of these parameters as indirect biomarkers of the illegal use of corticosteroids in meat production. The livers of 20 of the animals were analysed chemically for residues of corticosteroids. The morphology of the thymus was examined for adipose tissue infiltration, cortical atrophy and 'starry sky' appearance, and on the basis of these characteristics, the animals were considered to be negative, suspected or positive for illegal corticosteroid treatment. The animals considered to be negative had a mean cortisol concentration that was significantly higher (29 ng/ml) than that of the animals suspected for corticosteroid treatment (22 ng/ml). Using the chemical analysis as the gold standard for identifying illegally treated animals, the histological examination of the thymus had a sensitivity of 100 per cent and a specificity of 85 per cent. The samples that were positive by chemical analysis had cortisol concentrations of less than 2.0 ng/ml, whereas the mean cortisol concentration of the negative samples was 10.3 ng/ml.

  5. Indirect photomeric detection of anions in capillary electrophoresis using dyes as probes and electrolytes buffered with an isoelectric ampholyte.

    PubMed

    Johns, C; Macka, M; Haddad, P R

    2000-04-01

    The use of highly absorbing anionic dyes as probes and isoelectric ampholytes as buffers in background electrolytes (BGEs) combined with the use of a light emitting diode (LED) as a light source has been studied for ultrasensitive indirect photometric detection in capillary electrophoresis (CE). Potential dyes and buffers were evaluated based on characteristics relevant to indirect photometric detection principles, such as the electrophoretic mobility of the probe dye, its solubility and adsorption behaviour, and the isoelectric point and buffering capacity of the ampholytic buffer. Two dyes, tartrazine and naphthol yellow S, and histidine as the ampholytic buffer, were selected for detailed investigation. Purification of the probes was vital to avoid anionic impurities interfering with the detection. For the electrolytes containing a purified probe (0.5 mM) and histidine as the isoelectric buffer (p/ 7.7), hydroxypropylmethyl cellulose (approximately 0.05%) was effective in suppression of the electroosmotic flow (EOF). Analytical method performance characteristics were determined. For both probes, experimentally determined mobilities were generally close to literature values, excellent peak shapes and separation efficiencies of up to 298 000 theoretical plates were obtained, and detection limits were generally at the sub-microM level. For the naphthol yellow S-histidine BGE, linearity and reproducibility were also evaluated, with excellent linearity being observed over a range of 5-500 microM, and reproducibility (relative standard deviation, RSD) less than 1% for migration times and 2-8% for normalised peak areas. The approach developed was applied successfully to several real samples including tap water, mineral waters, and beer.

  6. Development and standardization of an in-house indirect ELISA for detection of duck antibody to fowl cholera.

    PubMed

    Poolperm, Pichayanut; Varinrak, Thanya; Kataoka, Yasushi; Tragoolpua, Khajornsak; Sawada, Takuo; Sthitmatee, Nattawooti

    2017-08-24

    Serological tests, such as agglutination and indirect hemagglutination assay (IHA), have been used to identify antibodies against Pasteurella multocida in poultry sera, but none are highly sensitive. An enzyme-linked immunosorbent assays (ELISA) has been used with varying degrees of success in attempts to monitor seroconversion in vaccinated poultry, but are not suitable for diagnosis. Commercial ELISA kits are available for chickens and turkeys, but not for ducks. The present study reports development and standardization of an in-house indirect ELISA for detection of duck antibody to fowl cholera. The characteristics of ELISA and IHA were analyzed using a one population Bayesian model assuming conditional dependence between the two diagnostic tests. An in-house indirect ELISA was developed using a heat extract antigen of P. multocida strain X-73 as a coating antigen and horseradish peroxidase conjugated goat anti-duck IgG antibody (dIgG-HRP). The checkerboard titration method was done using sera from ducks immunized with P. multocida bacterin as positive sera and 1day old duckling sera as negative sera. The heat extract antigen at 1μg/ml, sample serum at a dilution of 1:100, and dIgG-HRP 1:2000 were optimal concentrations for the assay. The cut-off value was 0.200. Of the duck sera, 89.05% (244/274) were considered seropositive by ELISA. Estimates for sensitivity and specificity of ELISA were higher than prior values with medians of 94.7% [95% posterior probability interval (PPI)=89.6-98.2%] and 87.2% (PPI=68.2-98.3%). Estimates for sensitivity of IHA were lower than prior values (median=97.6, PPI=93.2-99.7%) while the specificity was close to the prior value (median=76.5, PPI=65.8-85.4%). This finding suggests that an in-house indirect ELISA can be used to detect duck antibody to fowl cholera. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. An Improved Label-Free Indirect Competitive SPR Immunosensor and Its Comparison with Conventional ELISA for Ractopamine Detection in Swine Urine

    PubMed Central

    Wang, Sai; Zhao, Shuai; Wei, Xiao; Zhang, Shan; Liu, Jiahui; Dong, Yiyang

    2017-01-01

    Ractopamine (RCT) is banned for use in animals in many countries, and it is urgent to develop efficient methods for specific and sensitive RCT detection. A label-free indirect competitive surface plasmon resonance (SPR) immunosensor was first developed with a primary antibody herein and then improved by a secondary antibody for the detection of RCT residue in swine urine. Meanwhile, a pre-incubation process of RCT and the primary antibody was performed to further improve the sensitivity. With all the key parameters optimized, the improved immunosenor can attain a linear range of 0.3–32 ng/mL and a limit of detection (LOD) of 0.09 ng/mL for RCT detection with high specificity. Furthermore, the improved label-free SPR immunosenor was compared thoroughly with a conventional enzyme-linked immunosorbent assay (ELISA). The SPR immunosensor showed advantages over the ELISA in terms of LOD, reagent consumption, analysis time, experiment automation, and so on. The SPR immunosensor can be used as potential method for real-time monitoring and screening of RCT residue in swine urine or other samples. In addition, the design using antibody pairs for biosensor development can be further referred to for other small molecule detection. PMID:28300766

  8. Mode-shape-based mass detection scheme using mechanically diverse, indirectly coupled microresonator arrays

    NASA Astrophysics Data System (ADS)

    Glean, Aldo A.; Judge, John A.; Vignola, Joseph F.; Ryan, Teresa J.

    2015-02-01

    We explore vibration localization in arrays of microresonators used for ultrasensitive mass detection and describe an algorithm for identifying the location and amount of added mass using measurements of a vibration mode of the system. For a set of sensing elements coupled through a common shuttle mass, the inter-element coupling is shown to be proportional to the ratio of the element masses to the shuttle mass and to vary with the frequency mistuning between any two sensing elements. When any two elements have sufficiently similar frequencies, mass adsorption on one element can result in measurable changes to multiple modes of the system. We describe the effects on system frequencies and mode shapes due to added mass, in terms of mass ratio and frequency spacing. In cases in which modes are not fully localized, frequency-shift-based mass detection methods may give ambiguous results. The mode-shape-based detection algorithm presented uses a single measured mode shape and corresponding natural frequency to identify the location and amount of added mass. Mass detection in the presence of measurement noise is numerically simulated using a ten element sensor array. The accuracy of the detection scheme is shown to depend on the amplitude with which each element vibrates in the chosen mode.

  9. Climate and infectious disease: Use of remote sensing for detection of Vibrio cholerae by indirect measurement

    PubMed Central

    Lobitz, Brad; Beck, Louisa; Huq, Anwar; Wood, Byron; Fuchs, George; Faruque, A. S. G.; Colwell, Rita

    2000-01-01

    It has long been known that cholera outbreaks can be initiated when Vibrio cholerae, the bacterium that causes cholera, is present in drinking water in sufficient numbers to constitute an infective dose, if ingested by humans. Outbreaks associated with drinking or bathing in unpurified river or brackish water may directly or indirectly depend on such conditions as water temperature, nutrient concentration, and plankton production that may be favorable for growth and reproduction of the bacterium. Although these environmental parameters have routinely been measured by using water samples collected aboard research ships, the available data sets are sparse and infrequent. Furthermore, shipboard data acquisition is both expensive and time-consuming. Interpolation to regional scales can also be problematic. Although the bacterium, V. cholerae, cannot be sensed directly, remotely sensed data can be used to infer its presence. In the study reported here, satellite data were used to monitor the timing and spread of cholera. Public domain remote sensing data for the Bay of Bengal were compared directly with cholera case data collected in Bangladesh from 1992–1995. The remote sensing data included sea surface temperature and sea surface height. It was discovered that sea surface temperature shows an annual cycle similar to the cholera case data. Sea surface height may be an indicator of incursion of plankton-laden water inland, e.g., tidal rivers, because it was also found to be correlated with cholera outbreaks. The extensive studies accomplished during the past 25 years, confirming the hypothesis that V. cholerae is autochthonous to the aquatic environment and is a commensal of zooplankton, i.e., copepods, when combined with the findings of the satellite data analyses, provide strong evidence that cholera epidemics are climate-linked. PMID:10677480

  10. Climate and infectious disease: use of remote sensing for detection of Vibrio cholerae by indirect measurement.

    PubMed

    Lobitz, B; Beck, L; Huq, A; Wood, B; Fuchs, G; Faruque, A S; Colwell, R

    2000-02-15

    It has long been known that cholera outbreaks can be initiated when Vibrio cholerae, the bacterium that causes cholera, is present in drinking water in sufficient numbers to constitute an infective dose, if ingested by humans. Outbreaks associated with drinking or bathing in unpurified river or brackish water may directly or indirectly depend on such conditions as water temperature, nutrient concentration, and plankton production that may be favorable for growth and reproduction of the bacterium. Although these environmental parameters have routinely been measured by using water samples collected aboard research ships, the available data sets are sparse and infrequent. Furthermore, shipboard data acquisition is both expensive and time-consuming. Interpolation to regional scales can also be problematic. Although the bacterium, V. cholerae, cannot be sensed directly, remotely sensed data can be used to infer its presence. In the study reported here, satellite data were used to monitor the timing and spread of cholera. Public domain remote sensing data for the Bay of Bengal were compared directly with cholera case data collected in Bangladesh from 1992-1995. The remote sensing data included sea surface temperature and sea surface height. It was discovered that sea surface temperature shows an annual cycle similar to the cholera case data. Sea surface height may be an indicator of incursion of plankton-laden water inland, e.g., tidal rivers, because it was also found to be correlated with cholera outbreaks. The extensive studies accomplished during the past 25 years, confirming the hypothesis that V. cholerae is autochthonous to the aquatic environment and is a commensal of zooplankton, i.e., copepods, when combined with the findings of the satellite data analyses, provide strong evidence that cholera epidemics are climate-linked.

  11. Use of Indirect Calorimetry to Detect Overfeeding in Critically Ill Children: Finding the Appropriate Definition.

    PubMed

    Kerklaan, Dorian; Hulst, Jessie M; Verhoeven, Jennifer J; Verbruggen, Sascha C A T; Joosten, Koen F M

    2016-10-01

    Overfeeding during critical illness is associated with adverse effects such as metabolic disturbances and increased risk of infection. Because of the lack of sound studies with clinical endpoints, overfeeding is arbitrarily defined as the ratio caloric intake/measured resting energy expenditure (mREE) or alternatively as a comparison of measured respiratory quotient (RQ) to the predicted RQ based on the macronutrient intake (RQmacr). We aimed to compare definitions of overfeeding in critically ill mechanically ventilated children based on mREE, RQ, and caloric intake to find an appropriate definition. Indirect calorimetry measurements were performed in 78 mechanically ventilated children, median age 6.3 months. Enteral and/or parenteral nutrition was provided according to the local guidelines. Definitions used to indicate overfeeding were the ratio caloric intake/mREE of >110% and >120% and by the measured RQ > RQmacr + 0.05. The proportion of patients identified as overfed varied widely depending on the definition used, ranging from 22% (RQ > RQmacr + 0.05), to 40% and 50% (caloric intake/mREE of >120% and >110%, respectively). Linear regression analysis showed that all patients would be identified as overfed with the definition RQ > RQmacr + 0.05 when the ratio caloric intake/mREE exceeded 165%. Caloric intake was higher in children with a standard deviation-score weight for age <-2. The proportion of mechanically ventilated patients identified as overfed ranged widely depending on the definition applied. These currently used definitions fail to take into account several relevant factors affecting metabolism during critical illness and are therefore not generally applicable to the pediatric intensive care unit population.

  12. Climate and infectious disease: use of remote sensing for detection of Vibrio cholerae by indirect measurement

    NASA Technical Reports Server (NTRS)

    Lobitz, B.; Beck, L.; Huq, A.; Wood, B.; Fuchs, G.; Faruque, A. S.; Colwell, R.

    2000-01-01

    It has long been known that cholera outbreaks can be initiated when Vibrio cholerae, the bacterium that causes cholera, is present in drinking water in sufficient numbers to constitute an infective dose, if ingested by humans. Outbreaks associated with drinking or bathing in unpurified river or brackish water may directly or indirectly depend on such conditions as water temperature, nutrient concentration, and plankton production that may be favorable for growth and reproduction of the bacterium. Although these environmental parameters have routinely been measured by using water samples collected aboard research ships, the available data sets are sparse and infrequent. Furthermore, shipboard data acquisition is both expensive and time-consuming. Interpolation to regional scales can also be problematic. Although the bacterium, V. cholerae, cannot be sensed directly, remotely sensed data can be used to infer its presence. In the study reported here, satellite data were used to monitor the timing and spread of cholera. Public domain remote sensing data for the Bay of Bengal were compared directly with cholera case data collected in Bangladesh from 1992-1995. The remote sensing data included sea surface temperature and sea surface height. It was discovered that sea surface temperature shows an annual cycle similar to the cholera case data. Sea surface height may be an indicator of incursion of plankton-laden water inland, e.g., tidal rivers, because it was also found to be correlated with cholera outbreaks. The extensive studies accomplished during the past 25 years, confirming the hypothesis that V. cholerae is autochthonous to the aquatic environment and is a commensal of zooplankton, i.e., copepods, when combined with the findings of the satellite data analyses, provide strong evidence that cholera epidemics are climate-linked.

  13. Climate and infectious disease: use of remote sensing for detection of Vibrio cholerae by indirect measurement

    NASA Technical Reports Server (NTRS)

    Lobitz, B.; Beck, L.; Huq, A.; Wood, B.; Fuchs, G.; Faruque, A. S.; Colwell, R.

    2000-01-01

    It has long been known that cholera outbreaks can be initiated when Vibrio cholerae, the bacterium that causes cholera, is present in drinking water in sufficient numbers to constitute an infective dose, if ingested by humans. Outbreaks associated with drinking or bathing in unpurified river or brackish water may directly or indirectly depend on such conditions as water temperature, nutrient concentration, and plankton production that may be favorable for growth and reproduction of the bacterium. Although these environmental parameters have routinely been measured by using water samples collected aboard research ships, the available data sets are sparse and infrequent. Furthermore, shipboard data acquisition is both expensive and time-consuming. Interpolation to regional scales can also be problematic. Although the bacterium, V. cholerae, cannot be sensed directly, remotely sensed data can be used to infer its presence. In the study reported here, satellite data were used to monitor the timing and spread of cholera. Public domain remote sensing data for the Bay of Bengal were compared directly with cholera case data collected in Bangladesh from 1992-1995. The remote sensing data included sea surface temperature and sea surface height. It was discovered that sea surface temperature shows an annual cycle similar to the cholera case data. Sea surface height may be an indicator of incursion of plankton-laden water inland, e.g., tidal rivers, because it was also found to be correlated with cholera outbreaks. The extensive studies accomplished during the past 25 years, confirming the hypothesis that V. cholerae is autochthonous to the aquatic environment and is a commensal of zooplankton, i.e., copepods, when combined with the findings of the satellite data analyses, provide strong evidence that cholera epidemics are climate-linked.

  14. Indirect voltammetric detection of fluoride ions in toothpaste on a comb-shaped interdigitated microelectrode array.

    PubMed

    Cernanská, Monika; Tomcík, Peter; Jánosíková, Zuzana; Rievaj, Miroslav; Bustin, Dusan

    2011-02-15

    A novel technique based on dynamic electrochemistry for the detection of fluoride ions was developed. It is based on its strong complexation with ferric ion. Formed fluoroferric complex is cathodically inactive at the potential of the reduction of free ferric aquo ion. The voltammetric and amperometric response of platinum comb-shaped interdigitated microelectrode array is decreased after fluoride addition. This decrease serves for the quantification of fluoride ions added to the solution. The detection limit of 4.5×10(-5) mol dm(-3) was achieved when one of the segments of interdigitated microelectrode array (IDA) was used as an indicating electrode. The detection limit is about one order of magnitude lower than in the case of conventional platinum macroelectrode. In comparison with ISE electrodes this method is faster and also avoiding large error resulting from the antilogarithmization of ISE Nerstian response. The method was applied to the analysis of toothpaste.

  15. Guidelines to indirectly measure and enhance detection efficiency of stationary PIT tag interrogation systems in streams

    USGS Publications Warehouse

    Connolly, Patrick J.; Wolf, Keith; O'Neal, Jennifer S.

    2010-01-01

    With increasing use of passive integrated transponder (PIT) tags and reliance on stationary PIT tag interrogation systems to monitor fish populations, guidelines are offered to inform users how best to use limited funding and human resources to create functional systems that maximize a desired level of detection and precision. The estimators of detection efficiency and their variability as described by Connolly et al. (2008) are explored over a span of likely performance metrics. These estimators were developed to estimate detection efficiency without relying on a known number of fish passing the system. I present graphical displays of the results derived from these estimators to show the potential efficiency and precision to be gained by adding an array or by increasing the number of PIT-tagged fish expected to move past an interrogation system.

  16. Characterization of Antibodies and Development of an Indirect Competitive Immunoassay for Detection of Deamidated Gluten.

    PubMed

    Tranquet, Olivier; Lupi, Roberta; Echasserieau-Laporte, Valerie; Pietri, Manon; Larré, Colette; Denery-Papini, Sandra

    2015-06-10

    Diversification of gluten applications in the food and cosmetics industries was achieved through the production of water-soluble gluten that can be obtained by deamidation. Current analytical methods dedicated to gluten detection failed to detect deamidated gluten. After immunizing mice with the peptide LQPEEPFPE conjugated to keyhole limpet hemocyanin, five mouse monoclonal antibodies (mAbs) were produced and sequences of bound epitopes were determined as XPXEPFPE, where X is Q or E. The mAbs exhibited high specificity for deamidated gliadins and low molecular weight glutenin subunits. A competitive enzyme-linked immunosorbent assay (ELISA) based on INRA-DG1 mAb was developed with an IC50% of 85 ng/mL and a limit of detection of 25 ng/mL. The intra- and interassay coefficients of variation (CV) were <10% except for the interassay CV of the low-level control (40 ng/mL), which was 20%. This assay was capable of detecting three of the four deamidated gluten samples spiked in rice flour at 20 mg/kg.

  17. Phyllosilicate emission from protoplanetary disks: is the indirect detection of extrasolar water possible?

    PubMed

    Morris, Melissa A; Desch, Steven J

    2009-12-01

    Phyllosilicates are hydrous minerals formed by interaction between rock and liquid water, and are commonly found in meteorites that originate in the asteroid belt. Collisions between asteroids contribute to zodiacal dust, which therefore reasonably could include phyllosilicates. Collisions between planetesimals in protoplanetary disks may also produce dust that contains phyllosilicates. These minerals possess characteristic emission features in the mid-infrared and could be detectable in extrasolar protoplanetary disks. We have determined whether phyllosilicates in protoplanetary disks are detectable in the infrared, using instruments such as those on board the Spitzer Space Telescope and the Stratospheric Observatory for Infrared Astronomy (SOFIA). We calculated opacities for the phyllosilicates most common in meteorites and, using a two-layer radiative transfer model, computed the emission of radiation from a protoplanetary disk. We found that phyllosilicates present at the 3% level lead to observationally significant differences in disk spectra and should therefore be detectable with the use of infrared observations and spectral modeling. Detection of phyllosilicates in a protoplanetary disk would be diagnostic of liquid water in planetesimals in that disk and would demonstrate similarity to our own Solar System. We also discuss use of phyllosilicate emission to test the "water worlds" hypothesis, which proposes that liquid water in planetesimals should correlate with the inventory of short-lived radionuclides in planetary systems, especially (26)Al.

  18. Indirect effects of bioinsecticides on the nontarget fauna: The Camargue experiment calls for future research

    NASA Astrophysics Data System (ADS)

    Poulin, Brigitte

    2012-10-01

    Following its high selectivity and low toxicity to nontarget organisms, Bacillus thuringiensis var. israelensis (Bti) has become the most commonly used microbial agent to control mosquitoes worldwide. Considered non-toxic to mammals, birds, fish, plants and most aquatic organisms, Bti direct effects on the nontarget fauna are largely limited to non-biting midges (Chironomidae). Studies addressing the indirect effects of Bti through food web perturbations are scanty and showed no significant results. Mosquito-control in southern France was implemented in 1965 using various insecticides over 400 km of coast. In spite of a high mosquito nuisance, the Camargue wetlands were excluded from this control programme to preserve biodiversity. The expanding use of Bti has prompted the implementation of an experimental mosquito control in 2006 involving 2500 of the 25,000 ha of larval biotopes of the Camargue, accompanied by impact studies on the nontarget fauna. Using birds from natural and human-inhabited areas as model species, we assessed trophic perturbations caused by three years of Bti applications. The preliminary results of this 5-yr programme revealed significant effects of Bti spraying on abundance of reed-dwelling invertebrates serving as food to passerines, as well as on the diet and breeding success of house martins nesting in rural estates and small towns. Very few studies (if any) have provided such compelling evidence of an insecticide affecting vertebrate populations, putting into question the environmental-friendly character of Bti, at least in some areas. The significance of these results are discussed within a wider context and completed with an analysis of the current Bti bibliography to highlight and orient priorities for future research on this topic.

  19. Indirect Haemagglutination Test in Comparison with ELISA for Detection of Antibodies against Invasive Amoebiasis

    PubMed Central

    Dhanalakshmi, Sankaramoorthy; Meenachi, Chidambaram

    2016-01-01

    Introduction Diagnosis of amoebiasis is based on combination of tests like microscopy, imaging, serology and molecular methods. In absence of molecular techniques, serology can be used as an alternative aid. Various serological techniques were reported with different sensitivity and specificity. The diagnostic efficiency of these assays mainly depends on the characteristics of antigen that is being used and various conditions of performance. Aim To evaluate the efficiency of recombinant calcium binding domain containing protein by Indirect Haemagglutination Assay (IHA) against a commercial ELISA among amoebic liver abscess cases and control group. Materials and Methods The study was carried out during the period of 2011-2015 and blood samples were collected from suspected amoebiasis cases who were attending the clinics of Medicine and Paediatrics department, JIPMER. A total of 200 sera samples which included 100 Amoebic Liver Abscess (ALA), 50 cases of other parasitic infections and liver diseases and 50 presumed healthy controls were examined by IHA and commercial ELISA. In brief, chick cells were stabilized by Double Aldehyde Sensitization (DAS) method. Optimum Sensitizing Dose (OSD) of the antigen was determined. The test was performed in a U-bottomed microtiter plate with recombinant amoebic antigen (12.5μg/ml), incubated at Room Temperature (RT) for 2 hours. RIDASCREEN Entamoeba IgG ELISA kit which is commercially available was used to evaluate the samples as per manufacturer’s instruction. Results The overall sensitivity and specificity of the IHA was 62% and 96%, respectively when compared to ELISA having sensitivity and specificity of 69% and 90%, respectively. The positive predictive value of the IHA was 91% while negative predictive value was 79%. Similarly, the positive predictive value of the ELISA was 87% while negative predictive value was 74%. Conclusion As serology heavily suffers due to lack of a standardised test system employing the native

  20. Indirect Haemagglutination Test in Comparison with ELISA for Detection of Antibodies against Invasive Amoebiasis.

    PubMed

    Dhanalakshmi, Sankaramoorthy; Meenachi, Chidambaram; Parija, Subhash Chandra

    2016-08-01

    Diagnosis of amoebiasis is based on combination of tests like microscopy, imaging, serology and molecular methods. In absence of molecular techniques, serology can be used as an alternative aid. Various serological techniques were reported with different sensitivity and specificity. The diagnostic efficiency of these assays mainly depends on the characteristics of antigen that is being used and various conditions of performance. To evaluate the efficiency of recombinant calcium binding domain containing protein by Indirect Haemagglutination Assay (IHA) against a commercial ELISA among amoebic liver abscess cases and control group. The study was carried out during the period of 2011-2015 and blood samples were collected from suspected amoebiasis cases who were attending the clinics of Medicine and Paediatrics department, JIPMER. A total of 200 sera samples which included 100 Amoebic Liver Abscess (ALA), 50 cases of other parasitic infections and liver diseases and 50 presumed healthy controls were examined by IHA and commercial ELISA. In brief, chick cells were stabilized by Double Aldehyde Sensitization (DAS) method. Optimum Sensitizing Dose (OSD) of the antigen was determined. The test was performed in a U-bottomed microtiter plate with recombinant amoebic antigen (12.5μg/ml), incubated at Room Temperature (RT) for 2 hours. RIDASCREEN Entamoeba IgG ELISA kit which is commercially available was used to evaluate the samples as per manufacturer's instruction. The overall sensitivity and specificity of the IHA was 62% and 96%, respectively when compared to ELISA having sensitivity and specificity of 69% and 90%, respectively. The positive predictive value of the IHA was 91% while negative predictive value was 79%. Similarly, the positive predictive value of the ELISA was 87% while negative predictive value was 74%. As serology heavily suffers due to lack of a standardised test system employing the native antigen, there arises need to identify alternative source of

  1. A comparative indirect ELISA for the detection of henipavirus antibodies based on a recombinant nucleocapsid protein expressed in Escherichia coli.

    PubMed

    Chen, Ji-Ming; Yu, Meng; Morrissy, Chris; Zhao, Yong-Gang; Meehan, Greer; Sun, Ying-Xue; Wang, Qing-Hua; Zhang, Wei; Wang, Lin-Fa; Wang, Zhi-Liang

    2006-09-01

    The indirect ELISA is a simple and useful method for detection of pathogen-specific antibodies in animal sera. However, non-specific or background binding is often a problem, especially when recombinant proteins from Escherichia coli are used. In this study, a comparative indirect ELISA in which the total reactivity and the background binding were determined simultaneously on the same ELISA plate was reported. The background was determined by incubation of the test sera with excess free antigen to block specific binding. The sample was considered positive only when its total reactivity reading was higher than a pre-determined cut-off value and the ratio of the total reactivity to the background reading was more than 2.0. Using this approach, an antibody assay for henipaviruses using a recombinant Nipah virus nucleocapsid protein expressed in E. coli was developed. A total of 919 negative serum samples were tested in this assay and the specificity was 95.8%. In addition, eight positive experimental serum samples all tested positive. The use of recombinant protein as the ELISA antigen, instead of inactivated virus antigens, will be of significant advantage for countries where there is no facility of Biosafety level 4 to handle this group of zoonotic viruses.

  2. Change Detection Experiments Using Low Cost UAVs

    NASA Technical Reports Server (NTRS)

    Logan, Michael J.; Vranas, Thomas L.; Motter, Mark; Hines, Glenn D.; Rahman, Zia-ur

    2005-01-01

    This paper presents the progress in the development of a low-cost change-detection system. This system is being developed to provide users with the ability to use a low-cost unmanned aerial vehicle (UAV) and image processing system that can detect changes in specific fixed ground locations using video provided by an autonomous UAV. The results of field experiments conducted with the US Army at Ft. A.P.Hill are presented.

  3. Indirect dark matter detection limits from the ultrafaint Milky Way satellite Segue 1

    NASA Astrophysics Data System (ADS)

    Essig, Rouven; Sehgal, Neelima; Strigari, Louis E.; Geha, Marla; Simon, Joshua D.

    2010-12-01

    We use new kinematic data from the ultrafaint Milky Way satellite Segue 1 to model its dark matter distribution and derive upper limits on the dark matter annihilation cross section. Using gamma-ray flux upper limits from the Fermi satellite and MAGIC, we determine cross section exclusion regions for dark matter annihilation into a variety of different particles including charged leptons. We show that these exclusion regions are beginning to probe the regions of interest for a dark matter interpretation of the electron and positron fluxes from PAMELA, Fermi, and HESS, and that future observations of Segue 1 have strong prospects for testing such an interpretation. We additionally discuss prospects for detecting annihilation with neutrinos using the IceCube detector, finding that in an optimistic scenario a few neutrino events may be detected. Finally, we use the kinematic data to model the Segue 1 dark matter velocity dispersion and constrain Sommerfeld enhanced models.

  4. Indirect Dark Matter Detection Limits from the Ultra-Faint Milky Way Satellite Segue 1

    SciTech Connect

    Essig, Rouven; Sehgal, Neelima; Strigari, Louis E.; Geha, Marla; Simon, Joshua D.; /Carnegie Inst. Observ.

    2011-08-11

    We use new kinematic data from the ultra-faint Milky Way satellite Segue 1 to model its dark matter distribution and derive upper limits on the dark matter annihilation cross-section. Using gamma-ray ux upper limits from the Fermi satellite and MAGIC, we determine cross-section exclusion regions for dark matter annihilation into a variety of different particles including charged leptons. We show that these exclusion regions are beginning to probe the regions of interest for a dark matter interpretation of the electron and positron uxes from PAMELA, Fermi, and HESS, and that future observations of Segue 1 have strong prospects for testing such an interpretation. We additionally discuss prospects for detecting annihilation with neutrinos using the IceCube detector, finding that in an optimistic scenario a few neutrino events may be detected. Finally we use the kinematic data to model the Segue 1 dark matter velocity dispersion and constrain Sommerfeld enhanced models.

  5. A new indirect impedancemeter to detect microbial contaminations in agro-food industry.

    PubMed

    Ribeiro, T; Romestant, G; Depoortere, J; Pauss, A

    2003-01-01

    The impedancemetry method can be used in Microbiology to perform the detection, quantification and even identification of some bacteria. Basic knowledge about this subject can be stated from Ur and Brown (1975), Firstenberg-Eden and Eden (1984), the reviews of Silley and Forsythe (1996), and Wawerla et al. (1999). With Escherichia coli, Bacillus subtilis and Saccharomyces cerevisiae cultures, the conductimetric responses were highly replicable, and repeatable for inocula concentrations from 1 to 10(8) CFU mL(-1). The main use of such devices could be the detection of contaminations of foodstuff. Several of these foodstuffs incubated at 37 degrees C spontaneously release quite large amounts of CO2. Our impedancemeter, however, was able to detect an Escherichia coli presence in canned French beans down to 2.35 10(-2) colony forming units (CFU) mL(-1), and a Saccharomyces cerevisae contamination of apple purée in glass jars down to 6.1 10(-3) CFU mL(-1).

  6. Indirect Detection of Remanent Magnetization: A Procedure for the Composition of Initial Models for Inversion

    NASA Astrophysics Data System (ADS)

    Louro, V. H.; Mantovani, M. S.; Ribeiro, V. B.

    2012-12-01

    The remanent magnetization is a barrier in geophysical magnetic studies involving n-dimensional modeling, especially when the geological target does not present evidences of outcropping or from existing borehole analysis. Here, we present a methodology of indirect determination of the remanent magnetization using airborne magnetic data. The procedure is composed of three steps: (1) estimation of the borders and depth of the target through the enhanced horizontal derivatives, (2) a sweeping for the reduction to the magnetic pole that best represent the behavior of the target in the magnetic pole considering the vector sum of the known induced and the unknown remanent magnetizations, and (3) the modeling of a synthetic body, based on the recovered geometry and depth, on the directions of inclination and declination of the total magnetic field, and on the known induced field. Having set these parameters, the problem will be reduced to two variables: the magnetic susceptibility and the intensity of the total magnetic field. The apparent magnetic susceptibility may be inferred by a regional analysis of the geology (tectonics, nearby occurrences, previously studied cases of similar magnetic behavior, etc.), or directly inserted if the target of the survey is known. In the last case only the intensity of the total magnetization is left. For that, a new sweeping will be taken for the intensity of the total magnetization that generates a magnetic response which best approximates the original data. Once recovered the intensity of the total magnetic field, a simple vector subtraction will allow the determination of the remanence vector. This procedure was applied to 111 synthetic cases and 9 real scenarios in the center and southeast Brazil (from northwest to southeast: Catalão, Serra Negra, Salitre I, II and III, Araxá, Tapira, Pratinha I and Juquiá), having different types of magnetization: from a primarily induced to a very strong remanent. The synthetic cases were

  7. Enantiomeric separation of 1,3-dimethylamylamine by capillary electrophoresis with indirect UV detection using a dual-selector system.

    PubMed

    Přibylka, Adam; Švidrnoch, Martin; Ševčík, Juraj; Maier, Vítězslav

    2015-12-01

    The CE method employing an indirect UV detection for the enantioseparation of 1,3-dimethylamylamine (DMAA), widely used in various preworkout and dietary supplements labeled as a constituent of geranium extract has been developed. The dual-selector system consisting of negatively charged sulfated α-CD (1.1% w/v) and sulfated β-CD (0.2% w/v) in 5 mM phosphate/Tris buffer (pH 3.0) containing the addition of 10 mM benzyltriethylammonium chloride (BTEAC) as the chromophoric additive was used for the enantiomeric separation of DMAA stereoisomers with the LODs in the range of 7.82-9.24 μg/mL. The method was partly validated and applied for the determination of the stereoisomeric composition of DMAA in commercial dietary supplements to verify the potential natural origin of DMAA.

  8. The indirect detection of bleach (sodium hypochlorite) in beverages as evidence of product tampering.

    PubMed

    Jackson, David S; Crockett, David F; Wolnik, Karen A

    2006-07-01

    Bleach (sodium hypochlorite) has been identified as the adulterant in a relatively large number of product tamperings that have been investigated by the Forensic Chemistry Center (FCC) of the U.S. Food and Drug Administration. In this work, household bleach was added to 23 different beverages at each of three levels. The impact of sodium hypochlorite on these beverages over a 13-day study period was evaluated using the following techniques: diphenylamine spot test for oxidizing agents, potassium iodide-starch test paper for oxidizing agents, pH, iodometric titration for quantitating hypochlorite, ion chromatography for chloride and chlorate quantitation, automated headspace sampling with gas chromatography-flame ionization detection (GC-FID) for determination of chloroform, and visual and organoleptic observations. This study has shown that hypochlorite is fragile when added to most common beverages and typically breaks down either partially or completely over time. In cases where a beverage is suspected of being adulterated with bleach but tests for hypochlorite are negative, it is still possible to characterize the product to demonstrate that the results are consistent with the addition of bleach. An adulterated product will give a positive test for oxidizing agents using the diphenylamine spot test. It is likely that the pH of the adulterated product will be higher than a control of that product. Ion chromatographic analysis shows elevated chloride and chlorate as compared with a control. And, chloroform may also be detected by GC-FID especially if the beverage that was adulterated contains citric acid.

  9. Evaluation of Diverse Antisera, Conjugates, and Support Media for Detecting Bradyrhizobium japonicum by Indirect Enzyme-Linked Immunosorbent Assay

    PubMed Central

    Ayanaba, Abateni; Weiland, Karen D.; Zablotowicz, Robert M.

    1986-01-01

    We evaluated three antisera and four enzyme conjugates for the detection of Bradyrhizobium japonicum by an indirect enzyme-linked immunosorbent assay in microtiter plates. Nitrocellulose membrane sheets were then evaluated as an alternative support medium by using some combinations. Partially purified immunoglobulin G (IgG) or unpurified antisera to strain USDA 110 raised in rabbits, goats, or sheep was reacted in microtiter plates with alkaline phosphatase conjugated to protein A, goat anti-rabbit (GAR), sheep anti-rabbit (SAR), or rabbit anti-goat (RAG) IgG. Cultures or nodules containing homologous rhizobia were detected with equal sensitivity when protein A, GAR, or SAR was reacted with 5 μg of protein IgG per ml or a 1:800 titer of antisera from rabbits, but not goats or sheep. RAG reacted with IgG or antisera from goats or sheep. The detection limit was 2 × 105 rhizobia per well. Rhizobia were spotted on nitrocellulose sheets as an alternative support medium, followed by soaking in 5 μg of protein per ml as IgG and 1:4,000 dilutions of protein A or GAR conjugate. Rhizobia in serogroup 110 were detected with the dye combination Nitro Blue Tetrazolium-5-bromo-4-chloro-3-indolyl phosphate (NBT-BCIP), and rhizobia in serogroup 122 were detected with fast red-naphthol phosphate (FR-NP). At the conclusion of the 5-h assay, purple (NBT-BCIP) or red (FR-NP) spots were visible in positive reactions. The sensitivity of detection was about 1,000 rhizobial cells or 3 μg of nodules tissue. Images PMID:16347212

  10. Can Planck constrain indirect detection of dark matter in our Galaxy?

    NASA Astrophysics Data System (ADS)

    Delahaye, Timur; Böhm, Céline; Silk, Joseph

    2012-05-01

    We investigate the synchrotron emission (both intensity and morphology) associated with generic dark matter particles and make predictions for the Planck experiment, using the Fermi data and a model for the astrophysical sources. Our results indicate that the morphology (and not only the intensity) of the synchrotron emission from both dark matter annihilations plus astrophysical source is frequency dependent. Expected signals for light and heavy dark matter candidates seem sufficiently different to potentially delineate the value of the dark matter mass using a thorough comparison between LFI and HFI data.

  11. Indirect MRI of (17) o-labeled water using steady-state sequences: Signal simulation and preclinical experiment.

    PubMed

    Kudo, Kohsuke; Harada, Taisuke; Kameda, Hiroyuki; Uwano, Ikuko; Yamashita, Fumio; Higuchi, Satomi; Yoshioka, Kunihiro; Sasaki, Makoto

    2017-08-31

    Few studies have been reported for T2 -weighted indirect (17) O imaging. To evaluate the feasibility of steady-state sequences for indirect (17) O brain imaging. Signal simulation, phantom measurements, and prospective animal experiments were performed in accordance with the institutional guidelines for animal experiments. Signal simulations of balanced steady-state free precession (bSSFP) were performed for concentrations of (17) O ranging from 0.037-1.600%. Phantom measurements with concentrations of (17) O water ranging from 0.037-1.566% were also conducted. Six healthy beagle dogs were scanned with intravenous administration of 20% (17) O-labeled water (1 mL/kg). Dynamic 3D-bSSFP scans were performed at 3T MRI. (17) O-labeled water was injected 60 seconds after the scan start, and the total scan duration was 5 minutes. Based on the result of signal simulation and phantom measurement, signal changes in the beagle dogs were measured and converted into (17) O concentrations. The (17) O concentrations were averaged for every 15 seconds, and compared to the baseline (30-45 sec) with Dunnett's multiple comparison tests. Signal simulation revealed that the relationships between (17) O concentration and the natural logarithm of relative signals were linear. The intraclass correlation coefficient between relative signals in phantom measurement and signal simulations was 0.974. In the animal experiments, significant increases in (17) O concentration (P < 0.05) were observed 60 seconds after the injection of (17) O. At the end of scanning, mean respective (17) O concentrations of 0.084 ± 0.026%, 0.117 ± 0.038, 0.082 ± 0.037%, and 0.049 ± 0.004% were noted for the cerebral cortex, cerebellar cortex, cerebral white matter, and ventricle. Dynamic steady-state sequences were feasible for indirect (17) O imaging, and absolute quantification was possible. This method can be applied for the measurement of permeability and blood flow in the brain, and for

  12. Development of an indirect competitive immunochromatographic strip test for rapid detection and determination of anticancer drug, harringtonine.

    PubMed

    Sakamoto, Seiichi; Yusakul, Gorawit; Nuntawong, Poomraphie; Kitisripanya, Tharita; Putalun, Waraporn; Miyamoto, Tomofumi; Tanaka, Hiroyuki; Morimoto, Satoshi

    2017-03-24

    Harringtonine (HT) is a natural compound, which is mainly produced by the genus Cephalotaxus, and has been clinically utilized in China for the treatment of acute leukemia and lymphoma. However, the amounts of HT in the Cephalotaxus species are very small; therefore, plant tissue cultures have been focused upon to enhance HT production. Qualitative/quantitative methods for HT detection are required to screen superior cell lines. We developed a one-step indirect competitive immunochromatographic assay (ICA) using colloidal gold nanoparticles conjugated with highly specific monoclonal antibodies against HT (MAb 1D2) for simple, rapid, and sensitive detection of HT in plant samples. This ICA can be completed in 15min after dipping the strip into analytes with a limit of detection of ∼313ng/mL. In developed ICA, fiber pad which is usually used for conventional ICA, was not used to shorten the time for preparing chromatographic strip, resulting in a decrease in the volume of valuable analytes (20μL). Considering simplicity, rapidity, and sensitivity of the developed ICA, this study could be applied to a fieldwork study for finding new natural resources containing HT. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Indirect Dark Matter detection from Dwarf satellites: joint expectations from astrophysics and supersymmetry

    SciTech Connect

    Martinez, Gregory D.; Bullock, James S.; Kaplinghat, Manoj; Strigari, Louis E.; Trotta, Roberto E-mail: bullock@uci.edu E-mail: strigari@stanford.edu

    2009-06-01

    We present a general methodology for determining the gamma-ray flux from annihilation of dark matter particles in Milky Way satellite galaxies, focusing on two promising satellites as examples: Segue 1 and Draco. We use the SuperBayeS code to explore the best-fitting regions of the Constrained Minimal Supersymmetric Standard Model (CMSSM) parameter space, and an independent MCMC analysis of the dark matter halo properties of the satellites using published radial velocities. We present a formalism for determining the boost from halo substructure in these galaxies and show that its value depends strongly on the extrapolation of the concentration-mass (c(M)) relation for CDM subhalos down to the minimum possible mass. We show that the preferred region for this minimum halo mass within the CMSSM with neutralino dark matter is ∼ 10{sup −9}–10{sup −6} M{sub s}un. For the boost model where the observed power-law c(M) relation is extrapolated down to the minimum halo mass we find average boosts of about 20, while the Bullock et al (2001) c(M) model results in boosts of order unity. We estimate that for the power-law c(M) boost model and photon energies greater than a GeV, the Fermi space-telescope has about 20% chance of detecting a dark matter annihilation signal from Draco with signal-to-noise greater than 3 after about 5 years of observation.

  14. Indirect Dark Matter detection from Dwarf satellites: joint expectations from astrophysics and supersymmetry

    NASA Astrophysics Data System (ADS)

    Martinez, Gregory D.; Bullock, James S.; Kaplinghat, Manoj; Strigari, Louis E.; Trotta, Roberto

    2009-06-01

    We present a general methodology for determining the gamma-ray flux from annihilation of dark matter particles in Milky Way satellite galaxies, focusing on two promising satellites as examples: Segue 1 and Draco. We use the SuperBayeS code to explore the best-fitting regions of the Constrained Minimal Supersymmetric Standard Model (CMSSM) parameter space, and an independent MCMC analysis of the dark matter halo properties of the satellites using published radial velocities. We present a formalism for determining the boost from halo substructure in these galaxies and show that its value depends strongly on the extrapolation of the concentration-mass (c(M)) relation for CDM subhalos down to the minimum possible mass. We show that the preferred region for this minimum halo mass within the CMSSM with neutralino dark matter is ~ 10-9-10-6 Modot. For the boost model where the observed power-law c(M) relation is extrapolated down to the minimum halo mass we find average boosts of about 20, while the Bullock et al (2001) c(M) model results in boosts of order unity. We estimate that for the power-law c(M) boost model and photon energies greater than a GeV, the Fermi space-telescope has about 20% chance of detecting a dark matter annihilation signal from Draco with signal-to-noise greater than 3 after about 5 years of observation.

  15. New indirect measures of "inattentive" visual grouping in a change-detection task.

    PubMed

    Russell, Charlotte; Driver, Jon

    2005-05-01

    It has often been suggested that Gestalt-like visual grouping processes may operate preattentively, but Mack and Rock (1998) suggested that no visual grouping takes place under "inattention." We introduced a new method to assess this. While participants performed a demanding change-detection task on a small matrix at fixation, task-irrelevant background elements were arranged by color sinilarity into columns, rows, or pseudorandomly. Independent of any change in the target matrix, background grouping could also change or remain the same on each trial. This influenced accuracy of change judgments for the central task, even though background grouping or its change usually could not be explicitly reported when probed with surprise questions as in Mack and Rock. This suggests that visual grouping may arise implicitly under inattention and provides a new method for testing the boundaries of this processing. Here we extended the initial result to changes in background grouping remote from the target and to those occurring across an intervening saccade.

  16. First early time symmetry tuning experiments for indirect drive ignition implosions on the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Dewald, Eduard; Milovich, Jose; Thomas, Cliff; Glenn, Steven; Kyrala, George; Kline, John; Widmann, Klaus; MacKinnon, Andrew; Landen, Otto

    2011-10-01

    In ignition experiments on the National Ignition Facility (NIF), the symmetry of the hohlraum radiation drive for the first 2 ns is tuned using the re-emit technique. To achieve this, the capsule is replaced by a high-Z ``reemit'' sphere so that the incident drive symmetry can be inferred by soft x-ray imaging of the sphere re-emission pattern. We report on the first re-emit symmetry experiments performed on NIF in full ignition scale hohlraums that achieved 1% low mode accuracy. We will discuss results demonstrating the sensitivity of the radiation symmetry incident on the capsule to inner-to-outer laser beams wavelength shift that influences the inter-cone energy transfer, as well as to inner/outer beams power fraction that is used to tune the P2/P0 Legendre polynomial of the radiation flux at the capsule. This work performed under the auspices of the U.S. Department of Energy by LLNL under Contract DE-AC52-07NA27344.

  17. Direct and Indirect Pathways From Adverse Childhood Experiences to High School Dropout Among High-Risk Adolescents.

    PubMed

    Morrow, Anne S; Villodas, Miguel T

    2017-07-24

    Adverse childhood experiences (ACEs) are associated with an increased risk for school dropout. This study examined pathways from childhood adversity to school dropout through academic, behavioral, emotional, and social pathways. Data were collected prospectively from 728 adolescents and their caregivers who participated in the Longitudinal Studies of Child Abuse and Neglect and from child protective services records. Path analyses revealed a direct association between ACEs and dropout, as well as indirect effects through poor reading achievement and elevated externalizing problems. ACEs were associated with elevated internalizing problems, which were negatively associated with dropout. However, ACEs were not associated with peer influences. Implications of the identified mechanisms in the ACEs and school dropout association for future preventive interventions are discussed. © 2017 The Authors. Journal of Research on Adolescence © 2017 Society for Research on Adolescence.

  18. Status of Indirect Drive ICF Experiments on the National Ignition Facility

    SciTech Connect

    Dewald, E.

    2016-03-21

    In the quest to demonstrate Inertial Confinement Fusion (ICF) ignition of deuterium-tritium (DT) filled capsules and propagating thermonuclear burn with net energy gain (fusion energy/laser energy >1), recent experiments on the National Ignition Facility (NIF) have shown progress towards increasing capsule hot spot temperature (Tion>5 keV) and fusion neutron yield (~1016), while achieving ~2x yield amplification by alpha particle deposition. At the same time a performance cliff was reached, resulting in lower fusion yields than expected as the implosion velocity was increased. Ongoing studies of the hohlraum and capsule physics are attempting to disseminate possible causes for this performance ceiling.

  19. Recursive Indirect-Paths Modularity (RIP-M) for Detecting Community Structure in RNA-Seq Co-expression Networks.

    PubMed

    Rahmani, Bahareh; Zimmermann, Michael T; Grill, Diane E; Kennedy, Richard B; Oberg, Ann L; White, Bill C; Poland, Gregory A; McKinney, Brett A

    2016-01-01

    Clusters of genes in co-expression networks are commonly used as functional units for gene set enrichment detection and increasingly as features (attribute construction) for statistical inference and sample classification. One of the practical challenges of clustering for these purposes is to identify an optimal partition of the network where the individual clusters are neither too large, prohibiting interpretation, nor too small, precluding general inference. Newman Modularity is a spectral clustering algorithm that automatically finds the number of clusters, but for many biological networks the cluster sizes are suboptimal. In this work, we generalize Newman Modularity to incorporate information from indirect paths in RNA-Seq co-expression networks. We implement a merge-and-split algorithm that allows the user to constrain the range of cluster sizes: large enough to capture genes in relevant pathways, yet small enough to resolve distinct functions. We investigate the properties of our recursive indirect-pathways modularity (RIP-M) and compare it with other clustering methods using simulated co-expression networks and RNA-seq data from an influenza vaccine response study. RIP-M had higher cluster assignment accuracy than Newman Modularity for finding clusters in simulated co-expression networks for all scenarios, and RIP-M had comparable accuracy to Weighted Gene Correlation Network Analysis (WGCNA). RIP-M was more accurate than WGCNA for modest hard thresholds and comparable for high, while WGCNA was slightly more accurate for soft thresholds. In the vaccine study data, RIP-M and WGCNA enriched for a comparable number of immunologically relevant pathways.

  20. Indirect enzyme-linked immunosorbent assay for detection of Brucella melitensis-specific antibodies in goat milk.

    PubMed

    Funk, N D; Tabatabai, L B; Elzer, P H; Hagius, S D; Martin, B M; Hoffman, L J

    2005-02-01

    Brucella melitensis is the cause of brucellosis in sheep and goats, which often results in abortion. Few cases of B. melitensis infection in goats have occurred in the United States over the last 25 years. However, vigilance must be maintained, as it is for the bovine milk industry, to ensure that brucellosis is not introduced into the U.S. goat population. The objective of this study was to develop a sensitive and specific indirect enzyme-linked immunosorbent assay (iELISA) for the detection of B. melitensis-specific antibodies in goat milk. Brucella salt-extractable protein extract was employed as an antigen, and a horseradish peroxidase-labeled polyclonal anti-goat antibody was used as an anti-species conjugate. Thirteen of 13 (100%) individual infected goat milk samples tested positive and 134 of 134 (100%) uninfected bulk milk samples tested negative by the developed iELISA. Three positive milk samples with high, medium, and low absorbance values were used to simulate one positive animal in an otherwise negative herd. By this estimation, one high-titer animal could be detected in a herd of >1,600 animals. Detection estimates for medium- and low-titer animals were one positive animal per herd of <200 and 50 animals, respectively. Based on this estimation, it is recommended that herds be sampled in groups of 50 animals or less for bulk milk testing. The iELISA developed for this study was found to be sensitive and specific and shows potential for use as a bulk milk test for the detection of B. melitensis-specific antibodies in goat milk.

  1. Fluoroimmunoassay for detection of rubella-specific immunoglobulin M: comparison with indirect enzyme immunoassay and mu-chain capture.

    PubMed Central

    Echevarria, J M; de Ory, F; Najera, R

    1985-01-01

    The performance of a commercially-available method of fluoroimmunoassay (Rubella M FIAX, International Diagnostic Technology, Santa Clara, Calif.), designed for the detection of rubella-specific immunoglobulin M, was tested with 137 selected sera, including 52 from cases of primary rubella, 29 from healthy pregnant women, 21 containing rheumatoid factor, and 35 from cases of infectious mononucleosis (IM) caused by Epstein-Barr virus. The results were compared with those obtained by commercial indirect enzyme immunoassay (EIA) and EIA anti-mu chain capture tests. The fluoroimmunoassay technique showed a satisfactory level of sensitivity, but low values had to be interpreted with caution as false-positive results were detected with sera with rheumatoid factor and from IM cases, even after preliminary treatment of sera with the anti-human immunoglobulin G antisera provided in the kit. On the other hand, no false-positive results in the analysis of IM sera were seen in the EIA anti-mu chain capture method. Because of its sensitivity and specificity, we recommend the use of the latter technique for the diagnosis of primary rubella. PMID:2995439

  2. Ion chromatographic method for the simultaneous determination of nitrite and nitrate by post-column indirect fluorescence detection.

    PubMed

    Stalikas, Constantine D; Konidari, Constantina N; Nanos, Christos G

    2003-06-20

    This short paper highlights the suitability of ion chromatography with post-column indirect fluorescence detection to determine simultaneously nitrite and nitrate based on the quenching of tryptophan native fluorescence. The method uses an enhanced fluorescence mobile phase containing tryptophan and detects the suppression of fluorescence of the mobile phase due to the elution of the target ions. The phenomenon of fluorescence quenching of tryptophan is highly induced by the presence of phosphate ions. The quenched fluorescence intensity exhibits concentration dependence in the range 1-25 mg/l and 3-65 mg/l for nitrite and nitrate, respectively. The relative standard deviation for five replicates of a standard solution containing a mixture of 5 mg/l of nitrite and 10 mg/l of nitrate lies around 2.8%. This simple coupling technique results in a relatively sensitive, fast, and accurate method, allowing for both qualitative and quantitative analysis of nitrite and nitrate. The method can easily be implemented to real samples such as foodstuffs, fertilizers and soils and is proven to be precise and accurate when compared with reference methods.

  3. Development of an indirect competitive ELISA for detection of Campylobacter jejuni subsp.jejuni O:23 in foods.

    PubMed

    Hochel, I; Viochna, D; Skvor, J; Musil, M

    2004-01-01

    An indirect enzyme immunoassay for rapid detection of Campylobacter jejuni subsp. jejuni 0:23 has been developed. Optimum concentrations of immobilized cells, polyclonal chicken IgY, and rabbit anti-IgY antibody-horseradish peroxidase conjugate were 3.1 CFU/nL, 10 microg/mL, and 8 microg/mL, respectively. Under such conditions, the detection limit reached 50 CFU/microL, limit of quantification being 480 CFU/microL. By testing 5 chromogens, viz. 1,2-benzenediamine, 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid), 3,3',5,5'-tetramethylbenzidine, bi(4,4'-anisidine) and 3-methyl-2-benzothiazolinone hydrazone, in horseradish peroxidase substrate, 1,2-benzenediamine or 3,3',5,5'-tetramethylbenzidine as H-donors in the enzyme substrate provided the highest ELISA sensitivity. The applied polyclonal antibody was specific for homogeneous antigen. The cross-reactions were observed only with one strain of C. sputorum subsp. sputorum (21.5 %) and with G+ bacterium Micrococcus luteus (6.1 %). Preliminary tests have been performed with a limited number of artificially contaminated food samples. No matrix effects on the ELISA sensitivity were observed. The results (by means of ELISA) were comparable with those given by both a standard cultivation method performed according to CSN ISO 10272 and commercially available Singlepath Campylobacter GLISA-Rapid Test.

  4. SHARE 2012: subpixel detection and unmixing experiments

    NASA Astrophysics Data System (ADS)

    Kerekes, John P.; Ludgate, Kyle; Giannandrea, AnneMarie; Raqueno, Nina G.; Goldberg, Daniel S.

    2013-05-01

    The quantitative evaluation of algorithms applied to remotely sensed hyperspectral imagery require data sets with known ground truth. A recent data collection known as SHARE 2012, conducted by scientists in the Digital Imaging and Remote Sensing Laboratory at the Rochester Institute of Technology together with several outside collaborators, acquired hyperspectral data with this goal in mind. Several experiments were designed, deployed, and ground truth collected to support algorithm evaluation. In this paper, we describe two experiments that addressed the particular needs for the evaluation of subpixel detection and unmixing algorithms. The subpixel detection experiment involved the deployment of dozens of nearly identical subpixel targets in a random spatial array. The subpixel targets were pieces of wood painted either green or yellow. They were sized to occupy about 5% to 20% of the 1 m pixels. The unmixing experiment used novel targets with prescribed fractions of different materials based on a geometric arrangement of subpixel patterns. These targets were made up of different fabrics with various colors. Whole pixel swatches of the same materials were also deployed in the scene to provide in-scene endmembers. Alternatively, researchers can use the unmixing targets alone to derive endmembers from the mixed pixels. Field reflectance spectra were collected for all targets and adjacent background areas. While efforts are just now underway to evaluate the detection performance using the subpixel targets, initial results for the unmixing targets have demonstrated retrieved fractions that are close approximations to the geometric fractions. These data, together with the ground truth, are planned to be made available to the remote sensing research community for evaluation and development of detection and unmixing algorithms.

  5. Comparison of Indirect Hemagglutination and Immunodiffusion Tests for Detecting Type II Leukosis (Marek's) Infection in S- and K-Line Chickens1

    PubMed Central

    Hong, Chou C.; Sevoian, Martin

    1972-01-01

    The indirect hemagglutination and immunodiffusion tests were compared for detection of antigen and antibody to JM strain of leukosis virus infection between S- and K-line chickens. The indirect hemagglutination test was more sensitive than the immunodiffusion test for detecting the smallest amount of viral antigen and corresponding antibody in the plasma of infected chickens. The Cornell S-line had higher levels of antigen and antibody as compared with the Cornell K-line during the 20-week experimental period. Images PMID:4336659

  6. Multiplex RT-PCR and indirect immunofluorescence assays for detection and subtyping of human influenza virus in Tunisia.

    PubMed

    Ben M'hadheb, Manel; Harrabi, Myriam; Souii, Amira; Jrad-Battikh, Nadia; Gharbi, Jawhar

    2015-03-01

    Influenza viruses are negative stranded segmented RNA viruses belonging to Orthomyxoviridae family. They are classified into three types A, B, and C. Type A influenza viruses are classified into subtypes according to the antigenic characters of the surface glycoproteins: hemagglutinin (H) and neuraminidase (N). The aim of the present study is to develop a fast and reliable multiplex RT-PCR technique for detecting simultaneously the subtypes A/H1N1 and A/H3N2 of influenza virus. Our study included 398 patients (mean age 30.33 ± 19.92 years) with flu or flu-like syndromes, consulting physicians affiliated with collaborating teams. A multiplex RT-PCR detecting A/H1N1 and A/H3N2 influenza viruses and an examination by indirect immunofluorescence (IFI) were performed. In the optimized conditions, we diagnosed by IFI a viral infection in 90 patients (22.6 %): 85 cases of influenza type A, four cases of influenza type B, and only one case of coinfection with types A and B. An evaluation of the technique was performed on 19 clinical specimens positive in IFI, and we detected eight cases of A/H3N2, five cases of A/H1N1, one case of influenza virus type A which is not an H1N1 nor H3N2, and five negative cases. Multiplex RT-PCR is a sensitive technique allowing an effective and fast diagnosis of respiratory infections caused by influenza viruses in which the optimization often collides with problems of sensibility.

  7. The Preparation and Identification of a Monoclonal Antibody against Citrinin and the Development of Detection via Indirect Competitive ELISA

    PubMed Central

    Kalayu Yirga, Shimuye; Ling, Sumei; Yang, Yanling; Yuan, Jun; Wang, Shihua

    2017-01-01

    Citrinin (CTN) is a hepato-nephrotoxic mycotoxin produced by fungi genera of Aspergillus, Monauscus, and Penicillium. CTN contaminates grains, fruits, juices and vegetables, and causes various toxic effects to humans and animals. It has small molecular weight, which is non-immunogenic to animals. Thus, CTN was conjugated to bovine serum albumin (BSA) and ovalbumin (OVA), respectively, by amide bonds using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). Mice were immunized with CTN-BSA conjugates, and spleen cells of the immunized mice were fused with Sp2/0 myeloma cells to obtain 21H27 hybriodoma cell. Ascitic fluid of hybridoma cell was produced in mice abdomen, and purified using caprylic/ammonium sulfate precipitation method. The 21H27 anti-CTN mcAb was the IgG2a antibody subclass, and cross-reactivity results indicated that anti-CTN mcAb is specific to CTN with high affinity (2.0 × 108 L/mol). Indirect competitive ELISA (ic-ELISA) results showed that the linear range of detection was 0.01–5.96 ng/mL and the IC50 was 0.28 ng/mL with a lower detection limit (LOD) of 0.01 ng/mL. The average recovery was 93.8% ± 1.6% with a coefficient variation of 1.0%–4.3%. Hence, anti-CTN mcAb secreted by 21H27 hybridoma cell was successfully produced and can be used to detect CTN contaminated feed and foodstuffs. PMID:28304351

  8. Indirect ultraviolet detection of alkaline earth metal ions using an imidazolium ionic liquid as an ultraviolet absorption reagent in ion chromatography.

    PubMed

    Liu, Yong-Qiang; Yu, Hong

    2017-02-20

    A convenient and versatile method was developed for the separation and detection of alkaline earth metal ions by ion chromatography with indirect UV detection. The chromatographic separation of Mg(2+) , Ca(2+) , and Sr(2+) was performed on a carboxylic acid base cation exchange column using imidazolium ionic liquid/acid as the mobile phase, in which the imidazolium ionic liquid acted as an UV-absorption reagent. The effects of imidazolium ionic liquids, detection wavelength, acids in the mobile phase, and column temperature on the retention of Mg(2+) , Ca(2+) , and Sr(2+) were investigated. The main factors influencing the separation and detection were the background UV absorption reagent and the concentration of hydrogen ion in ion chromatography with indirect UV detection. The successful separation and detection of Mg(2+) , Ca(2+) , and Sr(2+) within 14 min were achieved using the selected chromatographic conditions, and the detection limits (S/N = 3) were 0.06, 0.12, and 0.23 mg/L, respectively. A new separation and detection method of alkaline earth metal ions by ion chromatography with indirect UV detection was developed, and the application range of ionic liquids was expanded.

  9. Cloning, expression and purification of duck hepatitis B virus (DHBV) core protein and its use in the development of an indirect ELISA for serologic detection of DHBV infection.

    PubMed

    Liu, Qiang; Jia, Renyong; Wang, Mingshu; Huang, Juan; Zhu, Dekang; Chen, Shun; Yin, Zhongqiong; Wang, Yin; Chen, Xiaoyue; Cheng, Anchun

    2014-05-01

    Infecting ducks with duck hepatitis B virus (DHBV) is widely accepted as a relevant model for studying aspects of human HBV infection. However, efficient and sensitive diagnostic methods for the various infection models are limited. In order to provide a more simple and convenient method for serologic diagnosis, we improved the production of recombinant DHBV viral capsid protein (core protein) and then used it to develop an indirect enzyme-linked immunosorbent assay (ELISA) for detecting anti-DHBc antibodies (DHBcAg ELISA) in DHBV-infected ducks. Given the positive/negative cut-off value, the maximum dilution of duck sera in which anti-DHBc antibodies could be detected was 1:12,800. In addition, the DHBcAg ELISA displayed no cross reactivity with duck antisera against duck circovirus (DuCV), duck plague virus (DPV), duck hepatitis virus (DHV), duck swollen head septicemia virus (DSHSV), avian influenza virus (AIV), Riemerella anatipestifer, Salmonella anatum, or Escherichia coli. Furthermore, the coefficients of variation (CVs) of inter-assay and intra-assay experiments were both below than 10 %. When compared to PCR for accuracy on clinical samples from cases of suspected DHBV infection, the DHBcAg showed 95.45 % coincidence with PCR. In conclusion, recombinant DHBc was readily produced and used to establish a simple DHBcAg ELISA that provided a highly specific and sensitive method for analysis of clinical samples.

  10. Nucleoprotein-based indirect enzyme-linked immunosorbent assay (indirect ELISA) for detecting antibodies specific to Ebola virus and Marbug virus.

    PubMed

    Huang, Yi; Zhu, Youjie; Yang, Mengshi; Zhang, Zhenqing; Song, Donglin; Yuan, Zhiming

    2014-12-01

    Full-length nucleoproteins from Ebola and Marburg viruses were expressed as His-tagged recombinant proteins in Escherichia coli and nucleoprotein-based enzyme-linked immunosorbent assays (ELISAs) were established for the detection of antibodies specific to Ebola and Marburg viruses. The ELISAs were evaluated by testing antisera collected from rabbit immunized with Ebola and Marburg virus nucleoproteins. Although little cross-reactivity of antibodies was observed in anti-Ebola virus nucleoprotein rabbit antisera, the highest reactions to immunoglobulin G (IgG) were uniformly detected against the nucleoprotein antigens of homologous viruses. We further evaluated the ELISA's ability to detect antibodies to Ebola and Marburg viruses using human sera samples collected from individuals passing through the Guangdong port of entry. With a threshold set at the mean plus three standard deviations of average optical densities of sera tested, the ELISA systems using these two recombinant nucleoproteins have good sensitivity and specificity. These results demonstrate the usefulness of ELISA for diagnostics as well as ecological and serosurvey studies of Ebola and Marburg virus infection.

  11. Ion chromatography with the indirect ultraviolet detection of alkali metal ions and ammonium using imidazolium ionic liquid as ultraviolet absorption reagent and eluent.

    PubMed

    Liu, Yong-Qiang; Yu, Hong

    2016-08-01

    Indirect ultraviolet detection was conducted in ultraviolet-absorption-agent-added mobile phase to complete the detection of the absence of ultraviolet absorption functional group in analytes. Compared with precolumn derivatization or postcolumn derivatization, this method can be widely used, has the advantages of simple operation and good linear relationship. Chromatographic separation of Li(+) , Na(+) , K(+) , and NH4 (+) was performed on a carboxylic acid base cation exchange column using imidazolium ionic liquid/acid/organic solvent as the mobile phase, in which imidazolium ionic liquids acted as ultraviolet absorption reagent and eluting agent. The retention behaviors of four kinds of cations are discussed, and the mechanism of separation and detection are described. The main factors influencing the separation and detection were the background ultraviolet absorption reagent and the concentration of hydrogen ion in the ion chromatography-indirect ultraviolet detection. The successful separation and detection of Li(+) , Na(+) , K(+) , and NH4 (+) within 13 min was achieved using the selected chromatographic conditions, and the detection limits (S/N = 3) were 0.02, 0.11, 0.30, and 0.06 mg/L, respectively. A new separation and analysis method of alkali metal ions and ammonium by ion chromatography with indirect ultraviolet detection method was developed, and the application range of ionic liquid was expanded. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Indirect competitive immunoassay for the detection of fungicide Thiabendazole in whole orange samples by Surface Plasmon Resonance.

    PubMed

    Estevez, M-Carmen; Belenguer, Jose; Gomez-Montes, Silvia; Miralles, Javier; Escuela, Alfonso M; Montoya, Angel; Lechuga, Laura M

    2012-12-07

    A highly sensitive and specific SPR-based competitive immunoassay for the detection of Thiabendazole (TBZ) has been developed. An indirect format where a TBZ-protein conjugate is immobilized onto gold surfaces has been selected. Under the optimal conditions, a LOD of 0.67 nM (0.13 μg L(-1)) and an IC(50) of 3.2 nM (0.64 μg L(-1)) have been achieved which are comparable to the values obtained by conventional ELISA. Analysis of real samples has been attempted by first evaluating the influence of complex matrix samples coming from whole oranges and secondly measuring samples containing TBZ previously evaluated by chromatographic methods. A methanolic extraction procedure followed by a simple dilution in assay buffer has proven to be sufficient to measure orange samples using the developed immunoassay with an excellent recovery percentage. The sensitivity and the feasibility of measuring whole orange samples demonstrate the effectiveness and robustness of the SPR biosensor, which can be useful for the determination of TBZ in food at concentrations below the Maximum Residue Levels (MRLs) established by the European legislation.

  13. Broadband excitation and indirect detection of nitrogen-14 in rotating solids using Delays Alternating with Nutation (DANTE)

    NASA Astrophysics Data System (ADS)

    Vitzthum, Veronika; Caporini, Marc A.; Ulzega, Simone; Bodenhausen, Geoffrey

    2011-09-01

    A train of short rotor-synchronized pulses in the manner of Delays Alternating with Nutations for Tailored Excitation (DANTE) applied to nitrogen-14 nuclei ( I = 1) in samples spinning at the magic angle at high frequencies (typically νrot = 62.5 kHz so that τrot = 16 μs) allows one to achieve uniform excitation of a great number of spinning sidebands that arise from large first-order quadrupole interactions, as occur for aromatic nitrogen-14 nuclei in histidine. With routine rf amplitudes ω1( 14N)/(2 π) = 60 kHz and very short pulses of a typical duration 0.5 < τp < 2 μs, efficient excitation can be achieved with 13 rotor-synchronized pulses in 13 τrot = 208 μs. Alternatively, with 'overtone' DANTE sequences using 2, 4, or 8 pulses per rotor period one can achieve efficient broadband excitation in fewer rotor periods, typically 2-4 τrot. These principles can be combined with the indirect detection of 14N nuclei via spy nuclei with S = ½ such as 1H or 13C in the manner of Dipolar Heteronuclear Multiple-Quantum Correlation (D-HMQC).

  14. Broadband excitation and indirect detection of nitrogen-14 in rotating solids using Delays Alternating with Nutation (DANTE).

    PubMed

    Vitzthum, Veronika; Caporini, Marc A; Ulzega, Simone; Bodenhausen, Geoffrey

    2011-09-01

    A train of short rotor-synchronized pulses in the manner of Delays Alternating with Nutations for Tailored Excitation (DANTE) applied to nitrogen-14 nuclei (I=1) in samples spinning at the magic angle at high frequencies (typically νrot=62.5 kHz so that τrot=16 μs) allows one to achieve uniform excitation of a great number of spinning sidebands that arise from large first-order quadrupole interactions, as occur for aromatic nitrogen-14 nuclei in histidine. With routine rf amplitudes ω1(14N)/(2π)=60 kHz and very short pulses of a typical duration 0.5<τp<2 μs, efficient excitation can be achieved with 13 rotor-synchronized pulses in 13 τrot=208 μs. Alternatively, with 'overtone' DANTE sequences using 2, 4, or 8 pulses per rotor period one can achieve efficient broadband excitation in fewer rotor periods, typically 2-4 τrot. These principles can be combined with the indirect detection of 14N nuclei via spy nuclei with S=½ such as 1H or 13C in the manner of Dipolar Heteronuclear Multiple-Quantum Correlation (D-HMQC). Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Brompheniramine as a novel probe for indirect UV detection and its application for the capillary electrophoresis of adamantane drugs.

    PubMed

    Prapatpong, Pornpan; Prutthiwanasan, Brompoj; Nuchtavorn, Nantana; Buranaphalin, Sawanya; Suntornsuk, Leena

    2017-03-01

    Brompheniramine, an antihistamine drug, was employed as a novel UV probe for capillary electrophoresis with indirect UV detection of adamantane drugs (memantine, amantadine, and rimantadine). The probe possesses high molar absorptivity of 24 × 10(3) L/mol cm at 6 mM, which enables the measurement of these nonchromophore analytes without derivatization. The simple background electrolyte (10 mM sodium dihydrogen phosphate (pH 5.0) containing 5 mM brompheniramine and 6 mM β-cyclodextrin) provided the separation of the analytes in a short time (7.5 min). Under these conditions, brompheniramine had similar mobility to that of the analyte ions resulting in symmetric peaks with minimal electrodispersion. The analytes displace the probe at a one-to-one ratio with transfer values close to unity. β-Cyclodextrin played a role in the resolution of the structurally similar adamantane derivatives. Method validation showed good linearity (r(2)  > 0.98), precision (%RSD ≤ 3.30), and accuracy (recoveries ranging from 98 to 109%). The proposed method was successfully applied to determine the adamantane content in pharmaceutical products.

  16. [Establishment of a high sensitive indirect ELISA for detecting specific antibodies against H9 subtype avian influenza virus].

    PubMed

    Zhang, Wei; Hou, Lidan; Song, Jie; Zhang, Shuang; Li, Yun; Li, Jing; Sun, Lei; Fan, Wenhui; Liu, Wenjun

    2017-08-25

    H9 subtype avian influenza virus causes worldwide epidemic, resulting in enormous economic losses of poultry production. In the present study, an indirect ELISA method was established for more accurate and specific detection. The recombinant protein of the globular head domain of HA of H9 subtype avian influenza virus was used as antigen. Specific blocking buffers and dilution buffers were determined to increase the sensitivity and specificity. The sensitivity of ELISA was higher than that of hemagglutination inhibition (HI) test. The coating antigen is very specific and no cross-reactivity with positive serum against H3N2, H5N2 and H7N9 subtype influenza viruses, Newcastle disease virus, avian infectious bronchitis virus, avian infectious disease virus, and egg drop syndrome virus. Two hundred of clinical sera samples were examined. The results indicate the coincidence rate between ELISA and HI test reached 97%. In addition, there was a positive correlation between OD450 values and the logarithm of HI titer to the base 2 of an individual serum sample (R2=0.981 1).

  17. Bayesian analysis of multiple direct detection experiments

    NASA Astrophysics Data System (ADS)

    Arina, Chiara

    2014-12-01

    Bayesian methods offer a coherent and efficient framework for implementing uncertainties into induction problems. In this article, we review how this approach applies to the analysis of dark matter direct detection experiments. In particular we discuss the exclusion limit of XENON100 and the debated hints of detection under the hypothesis of a WIMP signal. Within parameter inference, marginalizing consistently over uncertainties to extract robust posterior probability distributions, we find that the claimed tension between XENON100 and the other experiments can be partially alleviated in isospin violating scenario, while elastic scattering model appears to be compatible with the frequentist statistical approach. We then move to model comparison, for which Bayesian methods are particularly well suited. Firstly, we investigate the annual modulation seen in CoGeNT data, finding that there is weak evidence for a modulation. Modulation models due to other physics compare unfavorably with the WIMP models, paying the price for their excessive complexity. Secondly, we confront several coherent scattering models to determine the current best physical scenario compatible with the experimental hints. We find that exothermic and inelastic dark matter are moderatly disfavored against the elastic scenario, while the isospin violating model has a similar evidence. Lastly the Bayes' factor gives inconclusive evidence for an incompatibility between the data sets of XENON100 and the hints of detection. The same question assessed with goodness of fit would indicate a 2 σ discrepancy. This suggests that more data are therefore needed to settle this question.

  18. Characterization of an Indirect-Detection Amorphous Silicon Detector for Dosimetric Measurement of Intensity Modulated Photon Fields

    NASA Astrophysics Data System (ADS)

    Bailey, Daniel Wayne

    Indirect-detection amorphous silicon electronic imagers show much promise for measurement of radiation dose, particularly for pre-treatment verification of patient-specific intensity modulated radiotherapy plans. These instruments, commonly known as Electronic Portal Imaging Devices (EPIDs), have high data density, large detecting area, convenient electronic read-out, excellent positional reproducibility, and are quickly becoming standard equipment on today's medical megavoltage linear accelerators. However, because these devices were originally intended to be digital radiograph imagers and not dosimeters, the modeling, calibration, and prediction of their response to dose carries a number of challenges. For instance, EPID dose images exhibit off-axis dose errors of up to 18% with increasing distance from the central axis of the imager (as compared to dose predictions calculated by a commercially available treatment planning system). Furthermore, these off-axis errors are asymmetric, with higher errors in the in-plane direction than in the cross-plane direction. In this work, methods are proposed to account for EPID off-axis effects by precisely calculating off-axis output factors from experimental measurements to increase the accuracy of EPID absolute dose measurement. Using these methods, dose readings acquired over the entire surface of the detector agree to within 2% accuracy as compared to respective EPID dose predictions. Similarly, the percentage of measured dose points that agree with respective calculated dose points (using 3%, 3 mm criteria) improves by as much as 60% for off-axis intensity modulated photon fields. Furthermore, a number of clinical applications of EPID dosimetry are investigated, including pixel response constancy, the effect of data density on a common metric for quantitatively comparing measured vs. calculated dose, and the implementation of an electronic portal dosimetry program for radiotherapy quality assurance.

  19. Indirect detection of superoxide in RAW 264.7 macrophage cells using microchip electrophoresis coupled to laser-induced fluorescence.

    PubMed

    de Campos, Richard P S; Siegel, Joseph M; Fresta, Claudia G; Caruso, Giuseppe; da Silva, José A F; Lunte, Susan M

    2015-09-01

    Superoxide, a naturally produced reactive oxygen species (ROS) in the human body, is involved in many pathological and physiological signaling processes. However, if superoxide formation is left unregulated, overproduction can lead to oxidative damage to important biomolecules, such as DNA, lipids, and proteins. Superoxide can also lead to the formation of peroxynitrite, an extremely hazardous substance, through its reaction with endogenously produced nitric oxide. Despite its importance, quantitative information regarding superoxide production is difficult to obtain due to its high reactivity and low concentrations in vivo. MitoHE, a fluorescent probe that specifically reacts with superoxide, was used in conjunction with microchip electrophoresis (ME) and laser-induced fluorescence (LIF) detection to investigate changes in superoxide production by RAW 264.7 macrophage cells following stimulation with phorbol 12-myristate 13-acetate (PMA). Stimulation was performed in the presence and absence of the superoxide dismutase (SOD) inhibitors, diethyldithiocarbamate (DDC) and 2-metoxyestradiol (2-ME). The addition of these inhibitors resulted in an increase in the amount of superoxide specific product (2-OH-MitoE(+)) from 0.08 ± 0.01 fmol (0.17 ± 0.03 mM) in native cells to 1.26 ± 0.06 fmol (2.5 ± 0.1 mM) after PMA treatment. This corresponds to an approximately 15-fold increase in intracellular concentration per cell. Furthermore, the addition of 3-morpholino-sydnonimine (SIN-1) to the cells during incubation resulted in the production of 0.061 ± 0.006 fmol (0.12 ± 0.01 mM) of 2-OH-MitoE(+) per cell on average. These results demonstrate that indirect superoxide detection coupled with the use of SOD inhibitors and a separation method is a viable method to discriminate the 2-OH-MitoE(+) signal from possible interferences.

  20. Monocular pedestrian detection: survey and experiments.

    PubMed

    Enzweiler, Markus; Gavrila, Dariu M

    2009-12-01

    Pedestrian detection is a rapidly evolving area in computer vision with key applications in intelligent vehicles, surveillance, and advanced robotics. The objective of this paper is to provide an overview of the current state of the art from both methodological and experimental perspectives. The first part of the paper consists of a survey. We cover the main components of a pedestrian detection system and the underlying models. The second (and larger) part of the paper contains a corresponding experimental study. We consider a diverse set of state-of-the-art systems: wavelet-based AdaBoost cascade [74], HOG/linSVM [11], NN/LRF [75], and combined shape-texture detection [23]. Experiments are performed on an extensive data set captured onboard a vehicle driving through urban environment. The data set includes many thousands of training samples as well as a 27-minute test sequence involving more than 20,000 images with annotated pedestrian locations. We consider a generic evaluation setting and one specific to pedestrian detection onboard a vehicle. Results indicate a clear advantage of HOG/linSVM at higher image resolutions and lower processing speeds, and a superiority of the wavelet-based AdaBoost cascade approach at lower image resolutions and (near) real-time processing speeds. The data set (8.5 GB) is made public for benchmarking purposes.

  1. Near Real Time Ship Detection Experiments

    NASA Astrophysics Data System (ADS)

    Brusch, S.; Lehner, S.; Schwarz, E.; Fritz, T.

    2010-04-01

    A new Near Real Time (NRT) ship detection processor SAINT (SAR AIS Integrated Toolbox) was developed in the framework of the ESA project MARISS. Data are received at DLRs ground segment DLR-BN (Neustrelitz, Germany). Results of the ship detection are available on ftp server within 30 min after the acquisition started. The detectability of ships on Synthetic Aperture Radar (SAR) ERS-2, ENVISAT ASAR and TerraSAR-X (TS-X) images is validated by coastal (live) AIS and space AIS. The monitoring areas chosen for surveillance are the North-, Baltic Sea, and Cape Town. The detectability in respect to environmental parameters like wind field, sea state, currents and changing coastlines due to tidal effects is investigated. In the South Atlantic a tracking experiment of the German research vessel Polarstern has been performed. Issues of piracy in particular in respect to ships hijacked at the Somali coast are discussed. Some examples using high resolution images from TerraSAR-X are given.

  2. Mode-coupling and 3D effects in Indirect-Drive Rayleigh-Taylor experiments on OMEGA

    NASA Astrophysics Data System (ADS)

    Casner, Alexis; Huser, G.; Jadaud, J.-P.; Liberatore, S.; Galmiche, D.; Vandenboomgaerde, M.

    2006-10-01

    Indirect-Drive Rayleigh-Taylor experiments have been performed on the OMEGA laser facility since 2002 with rugby-ball shaped hohlraums [1]. A set of consistent data has been acquired for different single mode wavelengths (λ = 35, 50 and 70 μm) machined on brominated and germanium-doped samples. Hohlraum energetics was characterized by Dante measurements through the LEH while complementary shock breakout measurements or side-on radiography allow us to assess the x-ray flux incident on the wall-mounted sample. We recently address the problem of mode-coupling by comparing the growth of 2-mode patterns (λ = 35 and 70 μm), either in phase or in opposite phase. Depending on phase one or the other wavelength becomes predominant. Comparison between the FCI2 code calculations and the experimental data will be shown. We will also compare the experimental growth of 3D pattern (70 μm * 70 μm) with the equivalent 2D (λ =50 μm) one. [1] A. Casner et al., Proceedings of the 4^thIFSA Conference, Biarritz (2005).

  3. Litter quality indirectly influences community composition, reproductive mode and trophic structure of oribatid mite communities: a microcosm experiment.

    PubMed

    Gergócs, Veronika; Rétháti, Gabriella; Hufnagel, Levente

    2015-11-01

    Our knowledge of the assembly processes of species-rich oribatid mite communities is fairly limited. Also, very little information is available on the effects of habitat factors on these processes. In this paper, the role of litter quality in pattern formation was investigated in a microcosm experiment using the "home-field advantage" approach. Native (home) and foreign (away) types of microarthropod assemblages were extracted from three types of litter samples (Turkey oak, Scots pine and black locust tree), and transferred alive into 'home' and 'away' samples, which have been defaunated and reinoculated with microorganisms to form microcosms. Microarthropods were extracted from the microcosms after incubation for 3-12 months. In addition to species identification and abundance records, some chemical properties of the litter were measured. We hypothesized that oribatid mite communities deteriorate, the proportion of parthenogenetic individuals decreases and the proportion of omnivorous individuals increases in 'away' microcosms in contrast to 'home' systems. Pine and oak litter were favourable for all the three types of oribatid communities since their community traits in these types of litter were found to be similar to 'home' litter. Black locust litter was favourable only for its native oribatid community in the long run. The proportion of parthenogenetic individuals partly supported our hypothesis, mainly in black locust litter. The relative abundance of omnivorous individuals did not differ significantly between treatments. Litter quality is likely to influence oribatid mite assemblages only indirectly.

  4. Mine detection experiments using hyperspectral sensors

    NASA Astrophysics Data System (ADS)

    Winter, Edwin M.; Miller, Miranda A.; Simi, Christopher G.; Hill, Anthony B.; Williams, Timothy J.; Hampton, David; Wood, Mark; Zadnick, Jerry; Sviland, Marc D.

    2004-09-01

    Hyperspectral imaging is an important technology for the detection of surface and buried land mines from an airborne platform. For this reason, hyperspectral was included with SAR sensors in the two deployments that were executed by the CECOM RDEC Night Vision and Electronic Systems Directorate (NVESD) in Fall 2002 and in Spring 2003. The purpose of these deployments was to bring together a wide variety of airborne sensors for the detection of mines, with well ground-truthed targets. The hyperspectral sensors included the Airborne Hyperspectral Imager (AHI), a University of Hawaii LWIR HSI sensor and the Compact Airborne Spectral Sensor (COMPASS), an NVESD VNIR/SWIR sensor. Both a high frequency SAR and a ground penetrating radar were also flown. These experiments were carried out at sites where an extensive array of buried and surface mines were deployed. At the first location, on the east coast, the mines were deployed against several different backgrounds ranging from bare dirt to long grass. At the second location in the desert southwest, the mines were placed on backgrounds ranging from loose sand to mixed sand and vegetation. The COMPASS and AHI sensors were both placed on the Twin Otter aircraft, and data was collected with the airplane as low as 700 ft and as high as 4000 ft. In this paper, the data collected on surface mines will be reviewed, and specific examples from each background type presented. Spectral detection algorithms will be applied to the data and the results of the algorithm processing will be presented.

  5. Indirect immunofluorescence assay for the simultaneous detection of antibodies against clinically important old and new world hantaviruses.

    PubMed

    Lederer, Sabine; Lattwein, Erik; Hanke, Merle; Sonnenberg, Karen; Stoecker, Winfried; Lundkvist, Åke; Vaheri, Antti; Vapalahti, Olli; Chan, Paul K S; Feldmann, Heinz; Dick, Daryl; Schmidt-Chanasit, Jonas; Padula, Paula; Vial, Pablo A; Panculescu-Gatej, Raluca; Ceianu, Cornelia; Heyman, Paul; Avšič-Županc, Tatjana; Niedrig, Matthias

    2013-01-01

    In order to detect serum antibodies against clinically important Old and New World hantaviruses simultaneously, multiparametric indirect immunofluorescence assays (IFAs) based on biochip mosaics were developed. Each of the mosaic substrates consisted of cells infected with one of the virus types Hantaan (HTNV), Puumala (PUUV), Seoul (SEOV), Saaremaa (SAAV), Dobrava (DOBV), Sin Nombre (SNV) or Andes (ANDV). For assay evaluation, serum IgG and IgM antibodies were analyzed using 184 laboratory-confirmed hantavirus-positive sera collected at six diagnostic centers from patients actively or previously infected with the following hantavirus serotypes: PUUV (Finland, n=97); SEOV (China, n=5); DOBV (Romania, n=7); SNV (Canada, n=23); ANDV (Argentina and Chile, n=52). The control panel comprised 89 sera from healthy blood donors. According to the reference tests, all 184 patient samples were seropositive for hantavirus-specific IgG (n=177; 96%) and/or IgM (n=131; 72%), while all control samples were tested negative. In the multiparametric IFA applied in this study, 183 (99%) of the patient sera were IgG and 131 (71%) IgM positive (accordance with the reference tests: IgG, 96%; IgM, 93%). Overall IFA sensitivity for combined IgG and IgM analysis amounted to 100% for all serotypes, except for SNV (96%). Of the 89 control sera, 2 (2%) showed IgG reactivity against the HTNV substrate, but not against any other hantavirus. Due to the high cross-reactivity of hantaviral nucleocapsid proteins, endpoint titrations were conducted, allowing serotype determination in >90% of PUUV- and ANDV-infected patients. Thus, multiparametric IFA enables highly sensitive and specific serological diagnosis of hantavirus infections and can be used to differentiate PUUV and ANDV infection from infections with Murinae-borne hantaviruses (e.g. DOBV and SEOV).

  6. Indirect Immunofluorescence Assay for the Simultaneous Detection of Antibodies against Clinically Important Old and New World Hantaviruses

    PubMed Central

    Lederer, Sabine; Lattwein, Erik; Hanke, Merle; Sonnenberg, Karen; Stoecker, Winfried; Lundkvist, Åke; Vaheri, Antti; Vapalahti, Olli; Chan, Paul K. S.; Feldmann, Heinz; Dick, Daryl; Schmidt-Chanasit, Jonas; Padula, Paula; Vial, Pablo A.; Panculescu-Gatej, Raluca; Ceianu, Cornelia; Heyman, Paul; Avšič-Županc, Tatjana; Niedrig, Matthias

    2013-01-01

    In order to detect serum antibodies against clinically important Old and New World hantaviruses simultaneously, multiparametric indirect immunofluorescence assays (IFAs) based on biochip mosaics were developed. Each of the mosaic substrates consisted of cells infected with one of the virus types Hantaan (HTNV), Puumala (PUUV), Seoul (SEOV), Saaremaa (SAAV), Dobrava (DOBV), Sin Nombre (SNV) or Andes (ANDV). For assay evaluation, serum IgG and IgM antibodies were analyzed using 184 laboratory-confirmed hantavirus-positive sera collected at six diagnostic centers from patients actively or previously infected with the following hantavirus serotypes: PUUV (Finland, n = 97); SEOV (China, n = 5); DOBV (Romania, n = 7); SNV (Canada, n = 23); ANDV (Argentina and Chile, n = 52). The control panel comprised 89 sera from healthy blood donors. According to the reference tests, all 184 patient samples were seropositive for hantavirus-specific IgG (n = 177; 96%) and/or IgM (n = 131; 72%), while all control samples were tested negative. In the multiparametric IFA applied in this study, 183 (99%) of the patient sera were IgG and 131 (71%) IgM positive (accordance with the reference tests: IgG, 96%; IgM, 93%). Overall IFA sensitivity for combined IgG and IgM analysis amounted to 100% for all serotypes, except for SNV (96%). Of the 89 control sera, 2 (2%) showed IgG reactivity against the HTNV substrate, but not against any other hantavirus. Due to the high cross-reactivity of hantaviral nucleocapsid proteins, endpoint titrations were conducted, allowing serotype determination in >90% of PUUV- and ANDV-infected patients. Thus, multiparametric IFA enables highly sensitive and specific serological diagnosis of hantavirus infections and can be used to differentiate PUUV and ANDV infection from infections with Murinae-borne hantaviruses (e.g. DOBV and SEOV). PMID:23593524

  7. The Earth's velocity for direct detection experiments

    SciTech Connect

    McCabe, Christopher

    2014-02-01

    The Earth's velocity relative to the Sun in galactic coordinates is required in the rate calculation for direct detection experiments. We provide a rigorous derivation of this quantity to first order in the eccentricity of the Earth's orbit. We also discuss the effect of the precession of the equinoxes, which has hitherto received little explicit discussion. Comparing with other expressions in the literature, we confirm that the expression of Lee, Lisanti and Safdi is correct, while the expression of Lewin and Smith, the de facto standard expression, contains an error. For calculations of the absolute event rate, the leading order expression is sufficient while for modulation searches, an expression with the eccentricity is required for accurate predictions of the modulation phase.

  8. Detecting Dark Photons with Reactor Neutrino Experiments

    NASA Astrophysics Data System (ADS)

    Park, H. K.

    2017-08-01

    We propose to search for light U (1 ) dark photons, A', produced via kinetically mixing with ordinary photons via the Compton-like process, γ e-→A'e-, in a nuclear reactor and detected by their interactions with the material in the active volumes of reactor neutrino experiments. We derive 95% confidence-level upper limits on ɛ , the A'-γ mixing parameter, ɛ , for dark-photon masses below 1 MeV of ɛ <1.3 ×10-5 and ɛ <2.1 ×10-5, from NEOS and TEXONO experimental data, respectively. This study demonstrates the applicability of nuclear reactors as potential sources of intense fluxes of low-mass dark photons.

  9. Indirect Fist Percussion of the Liver Is a More Sensitive Technique for Detecting Hepatobiliary Infections than Murphy's Sign

    PubMed Central

    Ueda, Takeshi; Ishida, Eri

    2015-01-01

    Background. Murphy's sign and Charcot's triad are established clinical findings of acute cholecystitis and cholangitis, respectively, but both show low sensitivity and limited clinical application. We evaluated if indirect fist percussion of the liver improves the efficiency of diagnosing cholecystitis and cholangitis when used as a diagnostic adjunct. Methods. The presence/absence of right upper quadrant (RUQ) tenderness, Murphy's sign, and pain induced by indirect fist percussion of the liver was assessed, and the results were compared with the definite diagnosis based on ultrasound and additional examinations in patients aged over 18 who visited our outpatient clinic with suspected hepatobiliary diseases. Results. Four hundred and eight patients were investigated, and 40 had hepatobiliary infection (acute cholecystitis: 10, acute cholangitis: 28, liver abscess: 1, and hepatic cyst infection: 1). The sensitivity of indirect fist percussion of the liver for diagnosing hepatobiliary infection was 60%, being significantly higher than that of RUQ tenderness (33%) and Murphy's sign (30%), and its specificity was 85%. There was no significant improvement in sensitivity or diagnostic accuracy when Murphy's sign was combined with indirect fist percussion of the liver. Conclusion. Indirect fist percussion-induced liver pain is a useful clinical finding to diagnose hepatobiliary infection, with high-level sensitivity. PMID:26788057

  10. Indirect Fist Percussion of the Liver Is a More Sensitive Technique for Detecting Hepatobiliary Infections than Murphy's Sign.

    PubMed

    Ueda, Takeshi; Ishida, Eri

    2015-01-01

    Background. Murphy's sign and Charcot's triad are established clinical findings of acute cholecystitis and cholangitis, respectively, but both show low sensitivity and limited clinical application. We evaluated if indirect fist percussion of the liver improves the efficiency of diagnosing cholecystitis and cholangitis when used as a diagnostic adjunct. Methods. The presence/absence of right upper quadrant (RUQ) tenderness, Murphy's sign, and pain induced by indirect fist percussion of the liver was assessed, and the results were compared with the definite diagnosis based on ultrasound and additional examinations in patients aged over 18 who visited our outpatient clinic with suspected hepatobiliary diseases. Results. Four hundred and eight patients were investigated, and 40 had hepatobiliary infection (acute cholecystitis: 10, acute cholangitis: 28, liver abscess: 1, and hepatic cyst infection: 1). The sensitivity of indirect fist percussion of the liver for diagnosing hepatobiliary infection was 60%, being significantly higher than that of RUQ tenderness (33%) and Murphy's sign (30%), and its specificity was 85%. There was no significant improvement in sensitivity or diagnostic accuracy when Murphy's sign was combined with indirect fist percussion of the liver. Conclusion. Indirect fist percussion-induced liver pain is a useful clinical finding to diagnose hepatobiliary infection, with high-level sensitivity.

  11. An experiment to detect gut monopoles

    NASA Technical Reports Server (NTRS)

    Macneill, G.; Fegan, D. J.

    1985-01-01

    Recent advances in the development of Grand Unification Theories have led to several interesting predictions. One of these states that Grand Unification Monopoles (GUMs) exist as solutions in may nonabelian gauge theories. Another consequence of Unification is the possibility of baryon decay. The efficiency of the water tank detector in registering a Rubakov type decay will vary with both the interaction length and the GUM's velocity, expressed in terms of beta ( 0.01). The efficiency decreases at large values of because of the limited resolving time of the detector (approx. 50 ns). At lower values of Beta the time between interactions is such that the criterion of 4 events in 2 mu s can no longer be satisfied. The Rubakov experiment has now been in operation for almost 2 years with an estimated live time of 80%. During this time no candidate events have been observed leading to an estimated upper limit on the flux of 7.82 x 0.00001 m(-2) d(-1) Sr(-1). The ionization loss detection system has only recently come on line and as yet no results are available from this experiment.

  12. Analysis of the imaging performance in indirect digital mammography detectors by linear systems and signal detection models

    NASA Astrophysics Data System (ADS)

    Liaparinos, P.; Kalyvas, N.; Kandarakis, I.; Cavouras, D.

    2013-01-01

    PurposeThe purpose of this study was to provide an analysis of imaging performance in digital mammography, using indirect detector instrumentation, by combining the Linear Cascaded Systems (LCS) theory and the Signal Detection Theory (SDT). Observer performance was assessed, by examining frequently employed detectors, consisting of phosphor-based X-ray converters (granular Gd2O2S:Tb and structural CsI:Tl), coupled with the recently introduced complementary metal-oxide-semiconductor (CMOS) sensor. By applying combinations of various irradiation conditions (filter-target and exposure levels at 28 kV) on imaging detectors, our study aimed to find the optimum system set-up for digital mammography. For this purpose, the signal to noise transfer properties of the medical imaging detectors were examined for breast carcinoma detectability. MethodsAn analytical model was applied to calculate X-ray interactions within software breast phantoms and detective media. Modeling involved: (a) three X-ray spectra used in digital mammography: 28 kV Mo/Mo (Mo: 0.030 mm), 28 kV Rh/Rh (Rh: 0.025 mm) and 28 kV W/Rh (Rh: 0.060 mm) at different entrance surface air kerma (ESAK) of 3 mGy and 5 mGy, (b) a 5 cm thick Perspex software phantom incorporating a small Ca lesion of varying size (0.1-1 cm), and (c) two 200 μm thick phosphor-based X-ray converters (Gd2O2S:Tb, CsI:Tl), coupled to a CMOS based detector of 22.5 μm pixel size. ResultsBest (lowest) contrast threshold (CT) values were obtained with the combination: (i) W/Rh target-filter, (ii) 5 mGy (ESAK), and (iii) CsI:Tl-CMOS detector. For lesion diameter 0.5 cm the CT was found improved, in comparison to other anode/filter combinations, approximately 42% than Rh/Rh and 55% than Mo/Mo, for small sized carcinoma (0.1 cm) and approximately 50% than Rh/Rh and 125% than Mo/Mo, for big sized carcinoma (1 cm), considering 5 mGy X-ray beam. By decreasing lesion diameter and thickness, a limiting CT (100%) was occurred for size values less

  13. NATO TG-53: acoustic detection of weapon firing joint field experiment

    NASA Astrophysics Data System (ADS)

    Robertson, Dale N.; Pham, Tien; Scanlon, Michael V.; Srour, Nassy; Reiff, Christian G.; Sim, Leng K.; Solomon, Latasha; Thompson, Dorothea F.

    2006-05-01

    In this paper, we discuss the NATO Task Group 53 (TG-53) acoustic detection of weapon firing field joint experiment at Yuma Proving Ground during 31 October to 4 November 2005. The participating NATO countries include France, the Netherlands, UK and US. The objectives of the joint experiments are: (i) to collect acoustic signatures of direct and indirect firings from weapons such as sniper, mortar, artillery and C4 explosives and (ii) to share signatures among NATO partners from a variety of acoustic sensing platforms on the ground and in the air distributed over a wide area.

  14. Prototype detection unit for the CHIPS experiment

    NASA Astrophysics Data System (ADS)

    Pfützner, Maciej M.

    2017-09-01

    CHIPS (CHerenkov detectors In mine PitS) is an R&D project aiming to develop novel cost-effective neutrino detectors, focused on measuring the CP-violating neutrino mixing phase (δ CP). A single detector module, containing an enclosed volume of purified water, would be submerged in an existing lake, located in a neutrino beam. A staged approach is proposed with first detectors deployed in a flooded mine pit in Northern Minnesota, 7 mrad off-axis from the existing NuMI beam. A small proof-of-principle model (CHIPS-M) has already been tested and the first stage of a fully functional 10 kt module (CHIPS-10) is planned for 2018. One of the instruments submerged on board of CHIPS-M in autumn 2015 was a prototype detection unit, constructed at Nikhef. The unit contains hardware borrowed from the KM3NeT experiment, including 16 3 inch photomultiplier tubes and readout electronics. In addition to testing the mechanical design and data acquisition, the detector was used to record a large sample of cosmic ray muon events. The collected data is valuable for characterising the cosmic muon background and validating a Monte Carlo simulation used to optimise future designs. This paper introduces the CHIPS project, describes the design of the prototype unit, and presents the results of a preliminary data analysis.

  15. Comparison of direct (13)C and indirect (1)H-[(13)C] MR detection methods for the study of dynamic metabolic turnover in the human brain.

    PubMed

    Chen, Hao; De Feyter, Henk M; Brown, Peter B; Rothman, Douglas L; Cai, Shuhui; de Graaf, Robin A

    2017-10-01

    A wide range of direct (13)C and indirect (1)H-[(13)C] MR detection methods exist to probe dynamic metabolic pathways in the human brain. Choosing an optimal detection method is difficult as sequence-specific features regarding spatial localization, broadband decoupling, spectral resolution, power requirements and sensitivity complicate a straightforward comparison. Here we combine density matrix simulations with experimentally determined values for intrinsic (1)H and (13)C sensitivity, T1 and T2 relaxation and transmit efficiency to allow selection of an optimal (13)C MR detection method for a given application and magnetic field. The indirect proton-observed, carbon-edited (POCE) detection method provides the highest accuracy at reasonable RF power deposition both at 4T and 7T. The various polarization transfer methods all have comparable performances, but may become infeasible at 7T due to the high RF power deposition. 2D MR methods have limited value for the metabolites considered (primarily glutamate, glutamine and γ-amino butyric acid (GABA)), but may prove valuable when additional information can be extracted, such as isotopomers or lipid composition. While providing the lowest accuracy, the detection of non-protonated carbons is the simplest to implement with the lowest RF power deposition. The magnetic field homogeneity is one of the most important parameters affecting the detection accuracy for all metabolites and all acquisition methods. Copyright © 2017. Published by Elsevier Inc.

  16. Strangeness detection in ALICE experiment at LHC

    SciTech Connect

    Safarik, K.

    1995-07-15

    The authors present some parameters of the ALICE detector which concern the detection of strange particles. The results of a simulation for neutral strange particles and cascades, together with estimated rates are presented. They also briefly discuss the detection of charged K-mesons. Finally, they mention the possibility of open charm particle detection.

  17. HA1-specific indirect ELISA for serological detection of canine influenza virus H3N2 infection in dogs.

    PubMed

    Shim, Doo Hee; Kim, Jeong-Ki; Hong, Minki; Na, Woonsung; Park, Yong-A; Park, Seong Jun; Song, Daesub; Lee, Jae Myun; Kim, Hye Kwon

    2015-04-01

    An indirect ELISA using recombinant HA1 protein of canine influenza virus (CIV) as a coating antigen was developed and characterized for its application to serosurveillance in dogs. The CIV H3N2-specific indirect ELISA was developed using recombinant HA1 protein (baculovirus-expression system) as a coating antigen. A total of 65 CIV H3N2-positive or negative canine sera were tested by the indirect ELISA for receiver operating characteristic (ROC) analysis and results compared to those generated by the hemagglutination inhibition (HI) test. Canine sera collected 10 days following intranasal inoculation with canine H3N2, seasonal H3N2 (A/Brisbane/10/2007) or pandemic H1N1 influenza virus (A/California/04/2009) were used for the cross-reaction test. An adjusted optical density (OD) of 0.17 was determined to be the optimal cut-off value for seropositivity. The indirect ELISA showed 95.7% sensitivity and 94.7% specificity when compared to the HI test. A cross-reaction test was also performed using canine sera reactive with CIV H3N2, seasonal H3N2 (human) and pandemic H1N1 (human) influenza viruses. Based on the data generated in this study, the canine H3N2-associated ELISA using baculovirus expressed HA1 antigen will be useful for herd-based serological survey of the canine H3N2 virus infection in dogs. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Quantitation of underivatized branched-chain amino acids in sport nutritional supplements by capillary electrophoresis with direct or indirect UV absorbance detection.

    PubMed

    Qiu, Jun; Wang, Jinhao; Xu, Zhongqi; Liu, Huiqing; Ren, Jie

    2017-01-01

    The branched-chain amino acids (BCAAs) including leucine (Leu), isoleucine (Ile) and valine (Val) play a pivotal role in the human body. Herein, we developed capillary electrophoresis (CE) coupled with conventional UV detector to quantify underivatized BCAAs in two kinds of sport nutritional supplements. For direct UV detection at 195 nm, the BCAAs (Leu, two enantiomers of Ile and Val) were separated in a background electrolyte (BGE) consisting of 40.0 mmol/L sodium tetraborate, and 40.0 mmol/L β-cyclodextrin (β-CD) at pH 10.2. In addition, the indirect UV detection at 264 nm was achieved in a BGE of 2.0 mmol/L Na2HPO4, 10.0 mmol/L p-aminosalicylic acid (PAS) as UV absorbing probe, and 40.0 mmol/L β-CD at pH 12.2. The β-CD significantly benefited the isomeric separation of Leu, L- and D-Ile. The optimal conditions allowed the LODs (limit of detections) of direct and indirect UV absorption detection to be tens μmol/L level, which was comparable to the reported CE inline derivatization method. The RSDs (relative standard deviations) of migration time and peak area were less than 0.91% and 3.66% (n = 6). Finally, CE with indirect UV detection method was applied for the quantitation of BCAAs in two commercial sport nutritional supplements, and good recovery and precision were obtained. Such simple CE method without tedious derivatization process is feasible of quality control and efficacy evaluation of the supplemental proteins.

  19. A multi-species indirect ELISA for detection of non-structural protein 3ABC specific antibodies to foot-and-mouth disease virus.

    PubMed

    Hosamani, M; Basagoudanavar, S H; Tamil Selvan, R P; Das, Varsha; Ngangom, Pravina; Sreenivasa, B P; Hegde, Raveendra; Venkataramanan, R

    2015-04-01

    Reliable diagnostic tests that are able to distinguish infected from vaccinated animals are a critical component of regional control programs for foot-and-mouth disease (FMD) in the affected countries. Non-structural protein (NSP) serology based on the 3ABC protein has been widely used for this purpose, and several kits are commercially available worldwide. This report presents the development of a 3ABC-antigen-based indirect ELISA, employing a peroxidase-conjugated protein G secondary antibody that can detect antibodies from multiple species. Recombinant 3ABC protein was expressed in insect cells and purified using affinity column chromatography. Using this protein, an indirect ELISA was developed and validated for the detection of NSP antibodies in serum samples collected from animals with different status of FMD. Diagnostic sensitivity and specificity were found to be 95.8 (95 % CI: 92.8-97.8) and 97.45 % (95 % CI: 94.8-99.0), respectively. The in-house ELISA compared well with the commercially available prioCHECK FMDV NS-FMD kit, with a high agreement between the tests, as determined by the kappa coefficient, which was 0.87. The in-house ELISA showed higher sensitivity for detecting vaccinated and subsequently infected animals, when compared to the reference test. Both of the tests were able to detect NSP antibodies as early as 7-8 days after experimental infection.

  20. In vitro analysis of the radiodensity of indirect composites and ceramic inlay systems and its influence on the detection of cement overhangs.

    PubMed

    Soares, Carlos José; Santana, Fernanda Ribeiro; Fonseca, Rodrigo Borges; Martins, Luis Roberto Marcondes; Neto, Francisco Haiter

    2007-12-01

    The purpose of this study was to evaluate the radiodensity of indirect restorative systems and to determine its influence on detection of resin cement overhangs. Sixty sound molars with similar dimensions were selected, and MOD inlay preparations were made in a standardized fashion with 6 degrees taper of the walls. Restorations were made with a porcelain, Duceram LFC, and with three indirect composites, Solidex, Artglass, and Targis. Digital radiographic images were taken before and after cementation of the inlays (Digora system) and were analyzed on two regions, the cervical and the isthmus floor. Digital radiodensity measurements were performed on standardized points symmetrically distributed over each restoration and tooth structure. Cement overhangs were detected through visual analysis by three evaluators. Data were statistically analyzed utilizing ANOVA following Tukey's test (p < 0.05), showing that Solidex presented lower radiodensity than Duceram LFC, and both Artglass and Targis presented similar higher levels of radiodensity than the other groups. Radiodensity of cervical regions was always greater than for isthmus floor regions. Detection of the resin cement overhangs is easier observed on Solidex and Duceram LFC. Radiodensity is highly influenced by restorative material type and tooth regions. The detection of radiopaque resin cement overhangs is influenced by radiodensity of restorative materials.

  1. Prospects for detecting dark matter with neutrino telescopes in light of recent results from direct detection experiments

    NASA Astrophysics Data System (ADS)

    Halzen, Francis; Hooper, Dan

    2006-06-01

    Direct detection dark matter experiments, lead by the CDMS Collaboration, have placed increasingly stronger constraints on the cross sections for elastic scattering of weakly interacting massive particles (WIMPs) on nucleons. These results impact the prospects for the indirect detection of dark matter using neutrino telescopes. With this in mind, we revisit the prospects for detecting neutrinos produced by the annihilation of WIMPs in the Sun. We find that the latest bounds do not seriously limit the models most accessible to next generation kilometer-scale neutrino telescopes such as IceCube. This is largely due to the fact that models with significant spin-dependent couplings to protons are the least constrained and, at the same time, the most promising because of the efficient capture of WIMPs in the Sun. We identify models where dark matter particles are beyond the reach of any planned direct detection experiments while within reach of neutrino telescopes. In summary, we find that, even when contemplating recent direct detection results, neutrino telescopes still have the opportunity to play an important as well as complementary role in the search for particle dark matter.

  2. Establishing an indirect sandwich enzyme-linked-immunosorbent-assay (ELISA) for the detection of antibodies against Histomonas meleagridis from experimentally infected specific pathogen-free chickens and turkeys

    PubMed Central

    Windisch, M.; Hess, M.

    2010-01-01

    No serological method suitable for large screening of antibodies against Histomonas meleagridis in poultry is available so far, the objective targeted in the present investigation. Consequently, an ELISA was developed as a suitable tool for this purpose. Investigating serum samples from non-infected specific pathogen-free (spf) chickens and commercial turkeys a high-background signal was noticed when ELISA plates were directly coated with purified parasitic cells. This signal was significantly reduced by coating the plates with a polyclonal rabbit antibody, raised against histomonads, prior to the addition of the antigen. Adopting this approach five antigen preparations were compared and a high reproducibility could be demonstrated reflected by a very low coefficient of variation of 5.3% and 1.7% for the chicken and turkey sera, respectively. After this initial development all further experiments were carried out with one set of plates and the same antigen preparation. Investigating chicken sera obtained from birds infected at 14 days of life, OD values above a predetermined cut-off value were observed 2 weeks post-infection and a rise of IgG antibodies was noticed until 6 weeks post-infection, when the experiment was terminated. Non-protected turkeys infected at 6 weeks of age displayed an increasing IgG response until 14 days post-infection, prior to the death of animals due to histomonosis. In comparison, the majority of turkeys vaccinated with attenuated histomonads, obtained through prolonged passaging and challenged 4 weeks later with virulent parasites, displayed a demonstrable antibody response after the challenge only. Antibody titres increased until 4 weeks post-challenge when the birds were killed and the study was terminated. Altogether, the developed indirect sandwich ELISA proved to be a quick and efficient method to detect IgG antibodies against H. meleagridis in sera of experimentally infected chickens and turkeys and will be a helpful tool to

  3. Establishing an indirect sandwich enzyme-linked-immunosorbent-assay (ELISA) for the detection of antibodies against Histomonas meleagridis from experimentally infected specific pathogen-free chickens and turkeys.

    PubMed

    Windisch, M; Hess, M

    2009-04-06

    No serological method suitable for large screening of antibodies against Histomonas meleagridis in poultry is available so far, the objective targeted in the present investigation. Consequently, an ELISA was developed as a suitable tool for this purpose. Investigating serum samples from non-infected specific pathogen-free (spf) chickens and commercial turkeys a high-background signal was noticed when ELISA plates were directly coated with purified parasitic cells. This signal was significantly reduced by coating the plates with a polyclonal rabbit antibody, raised against histomonads, prior to the addition of the antigen. Adopting this approach five antigen preparations were compared and a high reproducibility could be demonstrated reflected by a very low coefficient of variation of 5.3% and 1.7% for the chicken and turkey sera, respectively. After this initial development all further experiments were carried out with one set of plates and the same antigen preparation. Investigating chicken sera obtained from birds infected at 14 days of life, OD values above a predetermined cut-off value were observed 2 weeks post-infection and a rise of IgG antibodies was noticed until 6 weeks post-infection, when the experiment was terminated. Non-protected turkeys infected at 6 weeks of age displayed an increasing IgG response until 14 days post-infection, prior to the death of animals due to histomonosis. In comparison, the majority of turkeys vaccinated with attenuated histomonads, obtained through prolonged passaging and challenged 4 weeks later with virulent parasites, displayed a demonstrable antibody response after the challenge only. Antibody titres increased until 4 weeks post-challenge when the birds were killed and the study was terminated. Altogether, the developed indirect sandwich ELISA proved to be a quick and efficient method to detect IgG antibodies against H. meleagridis in sera of experimentally infected chickens and turkeys and will be a helpful tool to

  4. First, Get Your Feet Wet: The Effects of Learning from Direct and Indirect Experience on Team Creativity

    ERIC Educational Resources Information Center

    Gino, Francesca; Argote, Linda; Miron-Spektor, Ella; Todorova, Gergana

    2010-01-01

    How does prior experience influence team creativity? We address this question by examining the effects of task experience acquired directly and task experience acquired vicariously from others on team creativity in a product-development task. Across three laboratory studies, we find that direct task experience leads to higher levels of team…

  5. Indirect immunofluorescence on HEp-2000 substrate is a sensitive method for detecting anti-Ro/SSA antibodies in patients with lupus erythematosus and/or photosensitivity.

    PubMed

    Cozzani, Emanuele; Drosera, Massimo; Siccardi, Marina; Babbini, Giovanni; Parodi, Aurora

    2008-07-01

    To evaluate the sensitivity of indirect immunofluorescence (IIF) utilizing HEp-2000 cells to detect antinuclear and anti-Ro/SSA antibodies. We examined 5949 sera samples from 2316 patients with connective tissue diseases. All sera were tested by IIF on HEp-2 cells as substrate and by counterimmunoelectrophoresis (CIE). The positive sera for anti-Ro/SSA antibodies by CIE were retested by IIF using HEp-2000 cells. The sera that were anti-Ro/SSA-positive in CIE but negative on HEp-2000 cells were tested by ELISA for the 60 and 52 subunits of Ro/SSA antigen. Our results confirm the high sensitivity (81%) of HEp-2000 cells in detecting anti Ro/SSA antibodies. Using the HEp-2000 substrate is a reliable, simple alternative method for detecting anti-Ro/SSA antibodies in a first-level screening test such as IIF, especially in patients with lupus erythematosus and/or photosensitivity.

  6. Analysis of γ-hydroxy butyrate by combining capillary electrophoresis-indirect detection and wall dynamic coating: application to dried matrices.

    PubMed

    Saracino, Maria A; Catapano, Maria C; Iezzi, Rosa; Somaini, Lorenzo; Gerra, Gilberto; Mercolini, Laura

    2015-11-01

    γ-Hydroxybutyric acid (GHB) is a powerful central nervous system depressant, currently used in medicine for the treatment of narcolepsy and alcohol dependence. In recent years, it has gained popularity among illegal club drugs, mainly because of its euphoric effects as well as doping agent and date rape drug. The purpose of the present work was the development of a rapid analytical method for the analysis of GHB in innovative biological matrices, namely dried blood spots (DBSs) and dried urine spots (DUSs). The analytical method is based on capillary zone electrophoresis with indirect UV absorption detection at 210 nm and capillary wall dynamic coating. The background electrolyte is composed of a phosphate buffer containing nicotinic acid (probe for detection) and cetyltrimethylammonium bromide (CTAB, reversal of electroosmosis in wall dynamic coating). The influence of probe and CTAB concentration, together with buffer pH, on migration time and signal response was investigated. Under the optimized conditions, analytical linearity and precision were satisfactory; absolute recovery values were also high (>90 %); the use of dried matrices (DBSs and DUSs) was advantageous as an alternative matrix to classical ones. No interferences were found either from the most common exogenous or from endogenous compounds. This analytical approach can offer a rapid, precise and accurate method for GHB determination in innovative biological samples, which could be important for screening purposes in clinical and forensic toxicology. Graphical Abstract CE method, by combined indirect UV detection and dynamic coating, for GHB determination in DBSs and DUSs.

  7. Development and evaluation of indirect enzyme-linked immunosorbent assay for a screening test to detect antibodies against classical swine fever virus.

    PubMed

    Sakoda, Yoshihiro; Wakamoto, Hiroaki; Tamura, Tehpin; Nomura, Takushi; Naito, Michiko; Aoki, Hiroshi; Morita, Hiroshi; Kida, Hiroshi; Fukusho, Akio

    2012-08-01

    An indirect enzyme-linked immunosorbent assay (ELISA) was developed for a screening test to detect antibodies against classical swine fever virus (CSFV). Viral glycoproteins, which were purified from swine kidney cells infected with CSFV ALD/A76 strain by the immunoaffinity purification using monoclonal antibody against E2 protein, were adsorbed on a microtiter plate as the antigen for the antibody detection. Each antibody titer of serum sample was expressed as a sample per positive value calculated with optical absorbance of each sample and that of a positive control. The advantage of this ELISA is its higher sensitivity: most sera containing more than 4 neutralization titers were determined to be positive. This ELISA is unable to discriminate between antibodies against CSFV and those against other ruminant pestiviruses, therefore positive sera in this ELISA should be evaluated by a cross-neutralization test using CSFV, bovine viral diarrhea virus, and border disease virus. Taken together, the indirect ELISA developed in this study is useful screening tool to detect antibodies against CSFV for the large-scale monitoring of classical swine fever.

  8. Development and application of an indirect immunoperoxidase assay for the detection of Duck swollen head hemorrhagic disease virus antigen in Pekin ducks (Anas platyrhynchos).

    PubMed

    Li, Chuanfeng; Shen, Chanjuan; Cheng, Anchun; Wang, Mingshu; Zhang, Na; Zhou, Yi; Zhu, Dekang; Jia, Renyong; Luo, Qihui; Chen, Xiaoyue

    2010-01-01

    An improved indirect immunoperoxidase assay (IPA) was developed to detect antigens of Duck swollen head hemorrhagic disease virus (DSHDV) in paraformaldehyde-fixed, paraffin-embedded tissues of Pekin ducks (Anas platyrhynchos). This technique used an indirect streptavidin-alkaline phosphatase labeling system with polyclonal antiserum developed against purified DSHDV antigens. Specimens from the experimentally inoculated Pekin ducks with DSHDV and archived paraffin-embedded tissues from natural cases of Duck viral swollen head hemorrhagic disease (DVSHD) were examined by clinical and histological criteria. Positive staining was most widely observed in the cytoplasm of the following organs: immune, digestive, and urinary organs, heart, lung, and trachea, which corresponded to the intracellular distribution of reovirus. The DSHDV antigens were first detected at 4 hr postinoculation in the bursa of Fabricius of infected ducks. Therefore, this method was suitable for the early diagnosis of DVSHD. Immunoperoxidase staining was not present in tissues and organs of sham-inoculated ducks (negative control). The IPA developed in the current study is a convenient, sensitive, and specific means of detecting DSHDV and is applicable to routine diagnosis, retrospective studies, and prospective studies of DSHDV infection in ducks.

  9. Sensitivity of lunar particle-detection experiments

    NASA Astrophysics Data System (ADS)

    Bray, Justin D.

    2017-03-01

    The use of the Moon as a detector volume for ultra-high-energy neutrinos and cosmic rays, by searching for the Askaryan radio pulse produced when they interact in the lunar regolith, has been attempted by a range of projects over the past two decades. In this contribution, I discuss some of the technical considerations relevant to these experiments, and their consequent sensitivity to ultra-high-energy particles. I also discuss some possible future experiments, and highlight their potential.

  10. Mikhailov's experiments on detection of magnetic charge

    SciTech Connect

    Akers, D.

    1988-08-01

    In a reanalysis of Mikhailov's experiments, it is argued that observations of magnetic charge g = (1/2)(1/137)(1/3)e on ferromagnetic aerosols are incorrect. Future experiments of the type conducted by Mikhailov must take into an account the component of particle velocity orthogonal to E and H. It is shown that Mikhailov's data are consistent with the existence of a Dirac unit of magnetic charge g = (137/2)e found in meson spectroscopy.

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

    PubMed Central

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

    2003-01-01

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

  12. Evidence for a Bubble-Competition Regime in Indirectly Driven Ablative Rayleigh-Taylor Instability Experiments on the NIF

    SciTech Connect

    Martinez, D. A.; Smalyuk, V. A.; Kane, J. O.; Casner, A.; Liberatore, S.; Masse, L. P.

    2015-05-29

    In this paper, we investigate on the National Ignition Facility the ablative Rayleigh-Taylor instability in the transition from weakly nonlinear to highly nonlinear regimes. A planar plastic package with preimposed two-dimensional broadband modulations is accelerated for up to 12 ns by the x-ray drive of a gas-filled Au radiation cavity with a radiative temperature plateau at 175 eV. This extended tailored drive allows a distance traveled in excess of 1 mm for a 130 μm thick foil. Measurements of the modulation optical density performed by x-ray radiography show that a bubble-merger regime for the Rayleigh-Taylor instability at an ablation front is achieved for the first time in indirect drive. Finally, the mutimode modulation amplitudes are in the nonlinear regime, grow beyond the Haan multimode saturation level, evolve toward the longer wavelengths, and show insensitivity to the initial conditions.

  13. Evidence for a bubble-competition regime in indirectly driven ablative Rayleigh-Taylor instability experiments on the NIF.

    PubMed

    Martinez, D A; Smalyuk, V A; Kane, J O; Casner, A; Liberatore, S; Masse, L P

    2015-05-29

    We investigate on the National Ignition Facility the ablative Rayleigh-Taylor instability in the transition from weakly nonlinear to highly nonlinear regimes. A planar plastic package with preimposed two-dimensional broadband modulations is accelerated for up to 12 ns by the x-ray drive of a gas-filled Au radiation cavity with a radiative temperature plateau at 175 eV. This extended tailored drive allows a distance traveled in excess of 1 mm for a 130  μm thick foil. Measurements of the modulation optical density performed by x-ray radiography show that a bubble-merger regime for the Rayleigh-Taylor instability at an ablation front is achieved for the first time in indirect drive. The mutimode modulation amplitudes are in the nonlinear regime, grow beyond the Haan multimode saturation level, evolve toward the longer wavelengths, and show insensitivity to the initial conditions.

  14. Evidence for a Bubble-Competition Regime in Indirectly Driven Ablative Rayleigh-Taylor Instability Experiments on the NIF

    NASA Astrophysics Data System (ADS)

    Martinez, D. A.; Smalyuk, V. A.; Kane, J. O.; Casner, A.; Liberatore, S.; Masse, L. P.

    2015-05-01

    We investigate on the National Ignition Facility the ablative Rayleigh-Taylor instability in the transition from weakly nonlinear to highly nonlinear regimes. A planar plastic package with preimposed two-dimensional broadband modulations is accelerated for up to 12 ns by the x-ray drive of a gas-filled Au radiation cavity with a radiative temperature plateau at 175 eV. This extended tailored drive allows a distance traveled in excess of 1 mm for a 130 μ m thick foil. Measurements of the modulation optical density performed by x-ray radiography show that a bubble-merger regime for the Rayleigh-Taylor instability at an ablation front is achieved for the first time in indirect drive. The mutimode modulation amplitudes are in the nonlinear regime, grow beyond the Haan multimode saturation level, evolve toward the longer wavelengths, and show insensitivity to the initial conditions.

  15. Evidence for a Bubble-Competition Regime in Indirectly Driven Ablative Rayleigh-Taylor Instability Experiments on the NIF

    DOE PAGES

    Martinez, D. A.; Smalyuk, V. A.; Kane, J. O.; ...

    2015-05-29

    In this paper, we investigate on the National Ignition Facility the ablative Rayleigh-Taylor instability in the transition from weakly nonlinear to highly nonlinear regimes. A planar plastic package with preimposed two-dimensional broadband modulations is accelerated for up to 12 ns by the x-ray drive of a gas-filled Au radiation cavity with a radiative temperature plateau at 175 eV. This extended tailored drive allows a distance traveled in excess of 1 mm for a 130 μm thick foil. Measurements of the modulation optical density performed by x-ray radiography show that a bubble-merger regime for the Rayleigh-Taylor instability at an ablation frontmore » is achieved for the first time in indirect drive. Finally, the mutimode modulation amplitudes are in the nonlinear regime, grow beyond the Haan multimode saturation level, evolve toward the longer wavelengths, and show insensitivity to the initial conditions.« less

  16. Indirect decentralized learning control

    NASA Technical Reports Server (NTRS)

    Longman, Richard W.; Lee, Soo C.; Phan, M.

    1992-01-01

    The new field of learning control develops controllers that learn to improve their performance at executing a given task, based on experience performing this specific task. In a previous work, the authors presented a theory of indirect learning control based on use of indirect adaptive control concepts employing simultaneous identification and control. This paper develops improved indirect learning control algorithms, and studies the use of such controllers in decentralized systems. The original motivation of the learning control field was learning in robots doing repetitive tasks such as on an assembly line. This paper starts with decentralized discrete time systems, and progresses to the robot application, modeling the robot as a time varying linear system in the neighborhood of the nominal trajectory, and using the usual robot controllers that are decentralized, treating each link as if it is independent of any coupling with other links. The basic result of the paper is to show that stability of the indirect learning controllers for all subsystems when the coupling between subsystems is turned off, assures convergence to zero tracking error of the decentralized indirect learning control of the coupled system, provided that the sample time in the digital learning controller is sufficiently short.

  17. Probing the deep nonlinear stage of the ablative Rayleigh-Taylor instability in indirect drive experiments on the National Ignition Facility

    SciTech Connect

    Casner, A. Masse, L.; Liberatore, S.; Loiseau, P.; Masson-Laborde, P. E.; Jacquet, L.; Martinez, D.; Moore, A. S.; Seugling, R.; Felker, S.; Haan, S. W.; Remington, B. A.; Smalyuk, V. A.; Farrell, M.; Giraldez, E.; Nikroo, A.

    2015-05-15

    Academic tests in physical regimes not encountered in Inertial Confinement Fusion will help to build a better understanding of hydrodynamic instabilities and constitute the scientifically grounded validation complementary to fully integrated experiments. Under the National Ignition Facility (NIF) Discovery Science program, recent indirect drive experiments have been carried out to study the ablative Rayleigh-Taylor Instability (RTI) in transition from weakly nonlinear to highly nonlinear regime [A. Casner et al., Phys. Plasmas 19, 082708 (2012)]. In these experiments, a modulated package is accelerated by a 175 eV radiative temperature plateau created by a room temperature gas-filled platform irradiated by 60 NIF laser beams. The unique capabilities of the NIF are harnessed to accelerate this planar sample over much larger distances (≃1.4 mm) and longer time periods (≃12 ns) than previously achieved. This extended acceleration could eventually allow entering into a turbulent-like regime not precluded by the theory for the RTI at the ablation front. Simultaneous measurements of the foil trajectory and the subsequent RTI growth are performed and compared with radiative hydrodynamics simulations. We present RTI growth measurements for two-dimensional single-mode and broadband multimode modulations. The dependence of RTI growth on initial conditions and ablative stabilization is emphasized, and we demonstrate for the first time in indirect-drive a bubble-competition, bubble-merger regime for the RTI at ablation front.

  18. Preparation of a monoclonal antibody and development of an indirect competitive ELISA for the detection of chlorpromazine residue in chicken and swine liver.

    PubMed

    Liu, Wei; Li, Weihua; Yin, Weiwei; Meng, Meng; Wan, Yuping; Feng, Caiwei; Wang, Shanliang; Xi, Rimo

    2010-08-30

    Chlorpromazine is a typical antipsychotic drug used to make food-producing animals calm and promote growth as feed additives. Accumulation of chlorpromazine in animal bodies would cause side effects in the circulatory and nervous systems, and have adverse effects on blood cells, the skin and the eye. To detect the chlorpromazine residue in food producing animals, an indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed based on preparation of an anti-chlorpromazine monoclonal antibody. The antibody generated from immunogen of cationic bovine serum albumin (cBSA) coupled with chlorpromazine showed high sensitivity toward chlorpromazine with an IC(50) value of 0.73 ppb. The ELISA method was applied to detect swine liver and chicken samples spiked by chlorpromazine and satisfactory results were obtained. The recovery rates in chicken and swine liver were in the range of 88-95% and 86-95%, respectively; the intra-assay coefficients of variation were both < 15.3% and < 13.5%, respectively. An indirect competitive ELISA method based on a monoclonal antibody towards chlorpromazine with excellent sensitivity and specificity has been successfully developed. The immunoassay provided in this study was a hopeful alternative to chromatography spectrometry for regulatory analysis of chlorpromazine residue in food-producing animals. Copyright (c) 2010 Society of Chemical Industry.

  19. Development of an ion-pair reversed-phase HPLC method with indirect UV detection for determination of phosphates and phosphites as impurities in sodium risedronate.

    PubMed

    Breuzovska, Katerina; Dimitrovska, Aneta; Kitanovski, Zoran; Petrusevska, Jelena; Ribarska, Jasmina Tonic; Jolevska, Suzana Trajkovic

    2010-01-01

    A method based on RP-HPLC with indirect UV detection was developed for the determination of phosphates and phosphites as impurities in sodium risedronate. RP separation of the phosphates and phosphites was achieved by adding tetrabutylammonium hydroxide as an ion-pairing agent in the mobile phase. Potassium hydrogen phthalate was added to the mobile phase as an ionic chromophore in order to obtain high background absorption of the mobile phase. Separation was performed on a C18 column using a mixture of pH 8.2 buffer (containing 0.5 mM tetrabutylammonium hydroxide and 1 mM phthalate) and acetonitrile (95 + 5, v/v) as the mobile phase, with indirect UV detection at 248 nm. The validation of the method included determination of specificity/selectivity, linearity, LOD, LOQ, accuracy, precision, and robustness. The LOD was 0.86 microg/mL for phosphates and 0.76 microg/mL for phosphites. The LOQ was 2.60 microg/mL for phosphates and 2.29 microg/mL for phosphites. The developed method is suitable for quantitative determination of phosphates and phosphites as impurities in QC of sodium risedronate.

  20. Complementary test of the dark matter self-interaction in dark U(1) model by direct and indirect dark matter detection

    SciTech Connect

    Chen, Chian-Shu; Lin, Guey-Lin; Lin, Yen-Hsun

    2016-01-07

    The halo dark matter (DM) can be captured by the Sun if its final velocity after the collision with a nucleus in the Sun is less than the escape velocity. We consider a selfinteracting dark matter (SIDM) model where U(1) gauge symmetry is introduced to account for the DM self-interaction. Such a model naturally leads to isospin violating DM-nucleon interaction, although isospin symmetric interaction is still allowed as a special case. We present the IceCube-PINGU 2σ sensitivity to the parameter range of the above model with 5 years of search for neutrino signature from DM annihilation in the Sun. This indirect detection complements the direct detection by probing those SIDM parameter ranges which are either the region for very small m{sub χ} or the region opened up due to isospin violations.

  1. Enrichment Double-Antibody Sandwich Indirect Enzyme-Linked Immunosorbent Assay That Uses a Specific Monoclonal Antibody for Sensitive Detection of Ralstonia solanacearum in Asymptomatic Potato Tubers

    PubMed Central

    Caruso, Paola; Gorris, María Teresa; Cambra, Mariano; Palomo, José Luis; Collar, Jesús; López, María M.

    2002-01-01

    Sensitive and specific routine detection of Ralstonia solanacearum in symptomless potato tubers was achieved by efficient enrichment followed by a reliable double-antibody sandwich indirect enzyme-linked immunosorbent assay based on the specific monoclonal antibody 8B-IVIA. This monoclonal antibody reacted with 168 typical R. solanacearum strains and did not recognize 174 other pathogenic or unidentified bacteria isolated from potato. The optimized protocol included an initial enrichment step consisting of shaking the samples in modified Wilbrink broth for 72 h at 29°C. This step enabled specific detection by the enzyme-linked immunosorbent assay of 1 to 10 CFU of R. solanacearum per ml of initial potato extract. Analysis of 233 commercial potato lots by this method provided results that coincided with the results of conventional methods. PMID:12089053

  2. Complementary test of the dark matter self-interaction in dark U(1) model by direct and indirect dark matter detection

    SciTech Connect

    Chen, Chian-Shu; Lin, Guey-Lin; Lin, Yen-Hsun E-mail: glin@cc.nctu.edu.tw

    2016-01-01

    The halo dark matter (DM) can be captured by the Sun if its final velocity after the collision with a nucleus in the Sun is less than the escape velocity. We consider a selfinteracting dark matter (SIDM) model where U(1) gauge symmetry is introduced to account for the DM self-interaction. Such a model naturally leads to isospin violating DM-nucleon interaction, although isospin symmetric interaction is still allowed as a special case. We present the IceCube-PINGU 2σ sensitivity to the parameter range of the above model with 5 years of search for neutrino signature from DM annihilation in the Sun. This indirect detection complements the direct detection by probing those SIDM parameter ranges which are either the region for very small m{sub χ} or the region opened up due to isospin violations.

  3. Development of a combined technique using a rapid one-step immunochromatographic assay and indirect competitive ELISA for the rapid detection of baicalin.

    PubMed

    Paudel, Madan Kumar; Putalun, Waraporn; Sritularak, Boonchoo; Morinaga, Osamu; Shoyama, Yukihiro; Tanaka, Hiroyuki; Morimoto, Satoshi

    2011-09-09

    A colloidal gold conjugated anti-baicalin monoclonal antibody (anti-BA MAb) was prepared and used in an immunochromatographic assay (ICA) for BA in Scutellariae Radix and Kampo medicines. This competitive ICA uses an anti-BA MAb which shows a high specificity for BA and baicalein. Its advantages include a short assay time (15 min), no dependence on any instrumental systems, and it can detect BA in plant materials and Kampo medicines. The limit of detection for the ICA was found to be around 0.6 μg mL(-1)of baicalin. Moreover, the usefulness of the combination of indirect competitive ELISA and the ICA using anti-BA MAb as a quality control method was confirmed for analysis of BA in Scutellariae Radix and Kampo medicines with a sufficient sensitivity (200 ng mL(-1) to 2 μg mL(-1)), obtainable in an easy and timely manner.

  4. Development and application of an indirect ELISA test for the detection of antibodies to Mycoplasma crocodyli infection in crocodiles (Crocodylus niloticus).

    PubMed

    Dawo, Fufa; Mohan, Krishna

    2007-01-31

    Non-availability of a standardized rapid serodiagnostic test for quick and accurate diagnosis of Mycoplasma crocodyli (M. crocodyli) infection in crocodiles was the underlining reason for conducting the present study. An indirect enzyme-linked immunosorbent assay (iELISA) for the detection of antibodies (Ab) to M. crocodyli infection in crocodile sera was developed using sonicated antigen (Ag) and anti-crocodile conjugate. The iELISA test was optimised with different reagents and at different steps. A cut-off value of percent positive greater than or equal to 53.47% resulted in an estimated sensitivity and specificity of 85.67 and 100%, respectively. The developed iELISA could be used for detection of Abs to M. crocodyli infection in crocodiles and may enable to understand the transmission of the disease.

  5. Indirect immunohistochemistry on skin biopsy for the detection of persistently infected cattle with bovine viral diarrhoea virus in Italian dairy herds.

    PubMed

    Luzzago, Camilla; Frigerio, Michela; Tolari, Francesco; Mazzei, Maurizio; Salvadori, Claudia; Del Piero, Fabio; Arispici, Mario

    2006-04-01

    Indirect immunohistochemistry (IHC) on skin biopsies for identification of persistently infected (PI) animals has been used as a parallel test to antigen and antibody ELISAs in a bovine viral diarrhoea (BVD) voluntary control program. The aim was to evaluate the reliability and feasibility of IHC on ear skin tissues to detect PI animals in field conditions, including both adult and calves under 6 months of age. In animals over 6 months of age skin biopsy and blood sample were collected at the same time, whereas in young calves blood sampling was performed when animals reached 6 months of age. One hundred and sixty-five animals were tested and immunohistochemical results were compared with those of antigen ELISA. In case of inconclusive results virus isolation and virus neutralization assays were performed. Agreement K value was 0.96. Immunohistochemical staining in positive animals was clearly detectable in the keratinocytes of the epidermis and adnexa.

  6. Indirect inversions

    NASA Astrophysics Data System (ADS)

    Sergienko, Olga

    2013-04-01

    Since Doug MacAyeal's pioneering studies of the ice-stream basal traction optimizations by control methods, inversions for unknown parameters (e.g., basal traction, accumulation patterns, etc) have become a hallmark of the present-day ice-sheet modeling. The common feature of such inversion exercises is a direct relationship between optimized parameters and observations used in the optimization procedure. For instance, in the standard optimization for basal traction by the control method, ice-stream surface velocities constitute the control data. The optimized basal traction parameters explicitly appear in the momentum equations for the ice-stream velocities (compared to the control data). The inversion for basal traction is carried out by minimization of the cost (or objective, misfit) function that includes the momentum equations facilitated by the Lagrange multipliers. Here, we build upon this idea, and demonstrate how to optimize for parameters indirectly related to observed data using a suite of nested constraints (like Russian dolls) with additional sets of Lagrange multipliers in the cost function. This method opens the opportunity to use data from a variety of sources and types (e.g., velocities, radar layers, surface elevation changes, etc.) in the same optimization process.

  7. Census cities experiment in urban change detection

    NASA Technical Reports Server (NTRS)

    Wray, J. R. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Computer compatible tapes for an early ERTS-1 multispectral scanner image over the San Francisco Bay area are being used to classify and analyze land use in this metropolitan region. NASA aircraft underflight data and land use maps from the Census Cities ERTS-1 experiment are providing training samples. The tape record has been reformatted for use with the LARSYSSA pattern recognition and classification algorithms developed at the Purdue University Laboratory for Applications of Remote Sensing. Trial land use classification systems are being compared with color infrared photography and ground truth data for San Jose and vicinity.

  8. Community-based clinic volunteering: an evaluation of the direct and indirect effects on the experience of health science college students.

    PubMed

    Bird, Yelena; Islam, Adiba; Moraros, John

    2016-01-18

    The present study was conducted in a multi service-learning, student managed and operated, community-based clinic. Its aim was to measure the direct and indirect effects of how proximal factors (i.e., 'management', 'support received', 'duration of involvement', and 'average time spent per month') and mediators (i.e., 'training received', 'motivation', and 'commitment') influence distal outcomes (i.e., 'performance', 'satisfaction', and 'overall experience') within a volunteer organization. Participants were recruited through the use of an email list server. An online survey was used containing multi-item measures from validated scales. Data were collected from 170 volunteers from July to August 2013. Data analysis used a structural equation modeling (SEM) framework for the estimation of direct and indirect effects on constructs and variables of interest. Only statistically significant relationships were reported at p < 0.05. In this study, there are several direct effects worthy of note. First, the proximal factor of 'management' plays an important role in influencing the mediators of 'motivation' (standardized beta = 0.55) and 'training received' (0.65) by the student volunteers but has a relatively small impact on their 'commitment' (0.39) to the organization. Second, the mediator of 'motivation' proved to have the strongest impact on the distal outcome of volunteer 'performance' and 'satisfaction' levels (0.41 and 0.58 respectively), whereas 'commitment' (0.44) was the key in determining their 'overall experience' with the organization. These results in turn, help contextualize the indirect effects observed in our study. Namely, the proximal factor of 'management' played a distinctive role in influencing the distal outcomes of volunteer 'performance' (0.32) and 'overall experience' (0.66), whereas the organizational 'support received' by the volunteers was key to their 'satisfaction' (0.21). The findings of the present study shed light into the direct

  9. Census cities experiment in urban change detection

    NASA Technical Reports Server (NTRS)

    Wray, J. R. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Work continues on mapping of 1970 urban land use from 1970 census contemporaneous aircraft photography. In addition, change detection analysis from 1972 aircraft photography is underway for several urban test sites. Land use maps, mosaics, and census overlays for the two largest urban test sites are nearing publication readiness. Preliminary examinations of ERTS-1 imagery of San Francisco Bay have been conducted which show that tracts of land of more than 10 acres in size which are undergoing development in an urban setting can be identified. In addition, each spectral band is being evaluated as to its utility for urban analyses. It has been found that MSS infrared band 7 helps to differentiate intra-urban land use details not found in other MSS bands or in the RBV coverage of the same scene. Good quality false CIR composites have been generated from 9 x 9 inch positive MSS bands using the Diazo process.

  10. Early time implosion symmetry from two-axis shock-timing measurements on indirect drive NIF experiments

    SciTech Connect

    Moody, J. D. Robey, H. F.; Celliers, P. M.; Munro, D. H.; Barker, D. A.; Baker, K. L.; Döppner, T.; Hash, N. L.; Berzak Hopkins, L.; LaFortune, K.; Landen, O. L.; LePape, S.; MacGowan, B. J.; Ralph, J. E.; Ross, J. S.; Widmayer, C.; Nikroo, A.; Giraldez, E.; Boehly, T.

    2014-09-15

    An innovative technique has been developed and used to measure the shock propagation speed along two orthogonal axes in an inertial confinement fusion indirect drive implosion target. This development builds on an existing target and diagnostic platform for measuring the shock propagation along a single axis. A 0.4 mm square aluminum mirror is installed in the ablator capsule which adds a second orthogonal view of the x-ray-driven shock speeds. The new technique adds capability for symmetry control along two directions of the shocks launched in the ablator by the laser-generated hohlraum x-ray flux. Laser power adjustments in four different azimuthal cones based on the results of this measurement can reduce time-dependent symmetry swings during the implosion. Analysis of a large data set provides experimental sensitivities of the shock parameters to the overall laser delivery and in some cases shows the effects of laser asymmetries on the pole and equator shock measurements.

  11. Development of polyclonal antibody-based indirect enzyme-linked immunosorbent assay for the detection of Alicyclobacillus strains in apple juice.

    PubMed

    Wang, Zhouli; Yue, Tianli; Yuan, Yahong; Cai, Rui; Guo, Caixia; Wang, Xin; Niu, Chen

    2012-11-01

    A sort of specific polyclonal anti-Alicyclobacillus antibody was generated by immunizing New Zealand white rabbits, and a sensitive indirect enzyme-linked immunosorbent assay (ELISA) was developed for Alicyclobacillus detection in apple juice. A set of experimental parameters such as concentration of antigen, dilutions of the antibody and goat anti-rabbit IgG-horseradish peroxidase conjugate, selection of the blocking reagent, incubation time, and temperature was optimized. The cross-reactivity of the antibody was evaluated by ELISA and the result was consistent with Western blot analysis. The detection limit of the ELISA was about 10(5) colony forming units (CFU)/mL in apple juice samples. Samples were detected by ELISA and conventional culture method, and the ELISA results gave a good agreement with the results obtained by plating on Alicyclobacillus acidoterrestris medium agar. ELISA takes a total detection time of 6 to 7 h, which is less than the time of conventional techniques requiring more than 24 to 48 h. These results indicated that the established ELISA was a potential useful analytical method for detection of Alicyclobacillus in apple juice. © 2012 Institute of Food Technologists®

  12. A novel fusion protein-based indirect enzyme-linked immunosorbent assay for the detection of bovine tuberculosis.

    PubMed

    Liu, Siguo; Guo, Sheping; Wang, Chunlai; Shao, Meili; Zhang, Xiuhua; Guo, Yang; Gong, Qiang

    2007-05-01

    Enzyme-linked immunosorbent assay (ELISA) for diagnosis of bovine tuberculosis has been widely explored over the years. Three Mycobacterium bovis-specific antigen genes, namely, mpb70, mpb83, and esat-6 were recombined in tandem by spliced overlap extension technology and expressed in Escherichia coli to obtain the fusion protein (rM70-83-E6). Western blot analysis showed that rM70-83-E6 can specifically react with bovine tuberculosis-positive sera but not those from cattle infected with other bovine diseases such as bovine paratuberculosis. An indirect ELISA (iELISA) method was established with rM70-83-E6 as the diagnostic antigen. The diagnostic criteria were determined using 150 serum samples from healthy cattle. Analyses of 85 serum samples from cattle with bovine tuberculosis and 100 serum samples from healthy cattle demonstrated that the sensitivity of the iELISA was 69.4% (59/85) and the specificity was 96.0% (96/100). Moreover, 46 out of 67 purified protein derivative (PPD) skin test-positive samples were also positive by iELISA, giving a positive coincidence of 68.7%, while all 50 PPD skin test-negative samples were negative by iELISA, giving a negative coincidence of 100%. The total coincidence between iELISA and the PPD skin test was 82.1%. This study demonstrated that iELISA using rM70-83-E6 antigen is simple, sensitive and easy to perform and can be used to analysis of a large number of samples for serodiagnosis of bovine tubercuiosis.

  13. [Detection of antibodies against Trypanosoma cruzi in Somoto, Nicaragua, using indirect ELISA and IFI on blood samples on filter paper].

    PubMed

    Palacios, X; Belli, A; Espino, A M

    2000-12-01

    We standardized a solid-phase enzyme-linked immunosorbent assay (ELISA) in order to study the presence of Trypanosoma cruzi antibodies in asymptomatic persons who live in an area of Nicaragua endemic for Chagas' disease. The test was standardized to analyze filter-paper blood samples, which are easy to transport. In the first phase of our investigation, ELISA was used to study 18 samples of total serum and 18 eluates of blood from patients with chronic Chagas' disease; 30 samples of serum and 30 eluates of blood from healthy people, used as negative controls; and 14 samples of serum and 14 eluates of blood from patients with cutaneous or visceral leishmaniasis, which were used to study cross-reactions. Both with the total-serum and the blood-eluate samples, the ELISA test provided 100% sensitivity and 90% specificity. Cross-reactions in the patient samples were observed only with visceral leishmaniasis. The second phase of our investigation was a population study that included eight rural communities in the area of Somoto, Nicaragua. Through random sampling, filter-paper blood samples were collected from 2,434 people (1,335 men and 1,099 women) from the communities of Aguas Calientes, El Brocal, La Manzana, Las Playas, Los Canales, Santa Isabel, Santa Rosa, and Santa Teresa. Studied by ELISA and by indirect immunofluorescence (IIF), the samples included 260 found seropositive by ELISA (10.7%), of which 207 were positive according to IIF (8.5%). With both techniques, the majority of seropositives were among women, but the difference between men and women was not statistically significant. There was a high level of agreement between the results obtained with the two techniques. There was an upward trend with age, with 5.4% of those found seropositive by ELISA being persons 10 years of age or younger and 42.7% of those found seropositive being older than 50. The vast majority of the individuals analyzed were asymptomatic.

  14. Diagnosis of tuberculosis in an Indian population by an indirect ELISA protocol based on detection of Antigen 85 complex: a prospective cohort study

    PubMed Central

    Kashyap, Rajpal S; Rajan, Anju N; Ramteke, Sonali S; Agrawal, Vijay S; Kelkar, Sanjivani S; Purohit, Hemant J; Taori, Girdhar M; Daginawala, Hatim F

    2007-01-01

    Background Diagnosis of tuberculosis (TB) remains problematic despite many new advanced diagnostic methods. A reliable and rapid diagnostic test, which could be performed in any standard pathology laboratory, would help to obtain definitive early diagnoses of TB. In the present study we describe a prospective evaluation for demonstrating Antigen (Ag) 85 complex in the sera from TB patients. Methods Indirect ELISA, employing monoclonal antibodies (mAb) against the purified Ag 85 complex, was used to demonstrate Ag 85 complex in sera from TB patients. Serum samples were obtained from 197 different groups of patients: confirmed TB {n = 24}, clinically diagnosed TB {n = 104}, disease controls {n = 49} and healthy controls {n = 20}. Receiver operating curve (ROC) was used to calculate the cut off value and comparison between TB and non-TB groups were done by the chi-square test. Results The indirect ELISA method, using an mAb against Ag 85 complex, yielded 82% sensitivity (95% confidence interval [CI] 67 to 93%) and 86% specificity (95% CI, 57 to 98%) for the diagnosis of TB. The serum positivities for Ag 85 complex in cases of confirmed and clinically diagnosed TB patients were 96% (23/24) and 79% (82/104) respectively, while the positivity for patients in the non-tuberculosis group was 14% (10/69). Conclusion The detection of Ag 85 complex in sera from TB patients by indirect ELISA using mAb against purified Ag 85 complex gives a reliable diagnosis and can be used to develop an immunodiagnostic assay with increased sensitivity and specificity. PMID:17620147

  15. Rapid Detection and Identification of Streptococcus Iniae Using a Monoclonal Antibody-Based Indirect Fluorescent Antibody Technique

    USDA-ARS?s Scientific Manuscript database

    Streptococcus iniae is among the major pathogens of a large number of fish species cultured in fresh and marine recirculating and net pen production systems . The traditional plate culture technique to detect and identify S. iniae is time consuming and may be problematic due to phenotypic variations...

  16. A review of traditional and contemporary assays for direct and indirect detection of Equid herpesvirus 1 in clinical samples.

    PubMed

    Balasuriya, Udeni B R; Crossley, Beate M; Timoney, Peter J

    2015-11-01

    Equid herpesvirus 1 (EHV-1) is one of the most economically important equine viral pathogens. Its clinical manifestations in horses vary from acute upper respiratory tract disease, abortion, or neonatal death, to neurological disease termed equine herpesviral myeloencephalopathy, which may lead to paralysis and a fatal outcome. Successful identification of EHV-1 infection in horses depends on a variety of factors such as suitable case selection with emphasis on timing of sample collection, selection of appropriate sample(s) based on the clinical manifestations, application of relevant diagnostic technique(s) and/or test(s), and careful evaluation and interpretation of laboratory results. Several traditional serologic and virus isolation assays have been described; however, these assays have inherent limitations that prevent rapid and reliable detection of EHV-1. The advent of molecular biologic techniques has revolutionized the diagnosis of infectious diseases in humans and animal species. Specifically, polymerase chain reaction (PCR)-based assays have allowed detection of nucleic acid in clinical specimens precisely and rapidly as compared to the traditional methods that detect the agent or antigen, or agent-specific antibodies in serum. The new molecular methods, especially real-time PCR, can be a very useful means of EHV-1 detection and identification. Veterinarians involved in equine practice must be aware of the advantages and disadvantages of various real-time PCR assays, interpretation of viral genetic marker(s), and latency in order to provide the best standard of care for their equine patients. © 2015 The Author(s).

  17. Development and validation of an indirect Enzyme-linked immunosorbent assay for the detection of antibodies against Schmallenberg virus in blood samples from ruminants.

    PubMed

    van der Heijden, H M J F; Bouwstra, R J; Mars, M H; van der Poel, W H M; Wellenberg, G J; van Maanen, C

    2013-10-01

    To detect Schmallenberg virus (SBV) infections in ruminants and to perform SBV epidemiological studies a cost-effective serological test is required. For these purposes an indirect whole virus Enzyme-linked Immunosorbent Assay (ELISA) for detection of SBV specific antibodies in ruminant blood samples was developed. Schmallenberg virus antigen was produced by propagation on Vero cells, partly purified and coated onto ELISA plates. The indirect ELISA procedure included the subsequent incubation of diluted samples, protein-G-HRP conjugate and TMB substrate solution. Net Optical Densities (OD) values were calculated and expressed as a sample to positive percentage (S/P%) by comparison of the average net OD with the OD of the positive control. Validation of this assay was performed using 633 samples from SBV-free sheep, goats and cattle, and 141 samples from SBV suspect ruminants. The diagnostic specificity was 98.8%. Test results of 86 ruminant serum samples using both the SBV-ELISA and an SBV virus neutralization test (VNT), designated as the gold standard serological test for SBV, showed good correlation: at an S/P cut-off of 15% only one VNT positive sample tested negative in the SBV ELISA. The diagnostic sensitivity of the ELISA, relative to the VNT, was 98.8% (95% CI: 93.3-100.0%). The ELISA showed a high repeatability (cv=6.5%) and reproducibility (100% agreement). It was concluded that this ELISA is a suitable test method for the detection of SBV antibodies in sera from cows, sheep and, possibly, goats.

  18. Estimating detection-effort curves for plants using search experiments.

    PubMed

    Moore, Joslin L; Hauser, Cindy E; Bear, Jennifer L; Williams, Nicholas S G; McCarthy, Michael A

    2011-03-01

    Recent studies suggest that plant detection is not perfect, even for large, highly visible plants. However, this is often not taken into account during plant surveys where failing to detect a plant when present can result in poor management and biodiversity outcomes. Including knowledge of imperfect detectability into survey design and evaluation is hampered by the paucity of empirical data, and in particular, how detectability will change with search effort, plant size and abundance, the surrounding vegetation, or observer experience. We carried out a search experiment to measure the detection-effort curve for the invasive species orange hawkweed (Hieracium aurantiacum) in Victoria, Australia. The probability that hawkweed was detected increased with increasing search effort and the number of plants at the location. While detection probability varied between observers, experience appeared to have little effect. Accounting for imperfect detectability in plant surveys holds much promise for improved survey design and biodiversity outcomes, and we encourage other researchers to undertake similar experiments to further our understanding of plant detectability.

  19. Evaluation of Vircell Enzyme-Linked Immunosorbent Assay and Indirect Immunofluorescence Assay for Detection of Antibodies against Legionella pneumophila

    PubMed Central

    Diederen, Bram M. W.; Kluytmans, Jan A. J. W.; Peeters, Marcel F.

    2006-01-01

    We evaluated the abilities of the Vircell immunoglobulin G (IgG) and IgM indirect immunofluorescence assay (IFA) for Legionella pneumophila serogroup 1, the IgM and IgG enzyme-linked immunosorbent assay (ELISA) for Legionella pneumophila serogroup 1, and the IgM-plus-IgG ELISA for Legionella pneumophila serogroups 1 to 6 to diagnose Legionnaires' disease (LD) in a well-described sample of patients with and without LD. Also, we determined the agreements, sensitivities, and specificities of the different Vircell assays in comparison to a validated ELISA (Serion classic ELISA). Clinical sensitivity and specificity were 74.6% and 96.6%, respectively, for the IgM IFA, 65.1% and 88.0% for the IgG IFA, 92.3% and 100% for the IgM ELISA, 43.3% and 96.6% for the IgG ELISA, and 90.8% and 100% for the IgM-plus-IgG ELISA. Compared to Serion classic ELISA, agreement, sensitivity, and specificity were 80.0%, 83.1%, and 78.4%, respectively, for the IgM IFA, 75.2%, 66.0%, and 79.5% for the IgG IFA, 89.5%, 82.0%, and 97.6% for the IgM ELISA, 81.9%, 88.9%, and 78.0% for the IgG ELISA, and 93.5%, 90.0%, and 96.6% for the IgM-plus-IgG ELISA. The value of a positive diagnostic result obtained by the Vircell IgM IFA, the Vircell IgG IFA, and the Vircell IgG ELISA might not be acceptable for a diagnostic assay. Both the high specificities and sensitivities of the Vircell IgM ELISA and the IgM-plus-IgG ELISA and the high correlation with the Serion classic ELISA indicate that they are useful in the diagnosis of LD. PMID:16522778

  20. Detection of platelet antibodies by enzyme-linked immunosorbent assay (ELISA). Comparative studies with the indirect immunofluorescence assay.

    PubMed

    Horai, S; Claas, F H; van Rood, J J

    1981-08-01

    A newly developed enzyme-linked immunosorbent assay (ELISA) for the detection of platelet antibodies was compared with the platelet immunofluorescence test (PIF). A good correlation was found between both assays. However, ELISA seems to be more sensitive than PIF. Some sera reacted only in ELISA whereas no sera were found that were negative in ELISA and positive in PIF. When comparing the antibody titres, ELISA is at least 8 times more sensitive than PIF.

  1. Development and evaluation of an indirect in situ polymerase chain reaction for the detection of porcine circovirus type 2 in formalin-fixed and paraffin-embedded tissue specimens.

    PubMed

    Lin, Chun-Ming; Jeng, Chian-Ren; Hsiao, Shih-Hsuan; Chang, Chih-Cheng; Liu, Chen-Hsuan; Tsai, Yi-Chieh; Chia, Mi-Yuan; Pang, Victor Fei

    2009-09-18

    Taking advantage of the high sensitivity of polymerase chain reaction (PCR) and the cell-localizing ability of in situ hybridization (ISH), an indirect in situ PCR (ISPCR) method was developed for detecting the distribution of porcine circovirus type 2 (PCV2) in formalin-fixed and paraffin-embedded inguinal lymph nodes obtained from clinically healthy PCV2-carrier pigs and postweaning multisystemic wasting syndrome (PMWS)-affected pigs. Comparisons of the relative sensitivity of indirect ISPCR with other routinely used diagnostic methods for PCV2 indicated that nested PCR was the most sensitive method followed by indirect ISPCR, conventional PCR, ISH, and immunohistochemical (IHC) staining. Although indirect ISPCR, ISH, and IHC staining all revealed a similar signal distribution pattern of PCV2, using indirect ISPCR allowed specific amplification and detection of previously uneasily detected PCV2 signal than by routine ISH or IHC staining, particularly in those cells within the germinal center in clinically healthy PCV2-carrier pigs. Furthermore, six different PCV2 signal expression patterns in conjunction with the correlated lymphoid lesion stages were classified to describe the tissue morphological changes and viral infection. The result indicates that indirect ISPCR is a more effective, cell-based diagnostic tool with good specificity to detect limited PCV2 infection in formalin-fixed and paraffin-embedded tissue specimens and it would be a useful tool for further exploring the pathogenesis of PCV2 infection.

  2. Application of an indirect immunofluorescent staining method for detection of Salmonella enteritidis in paraffin slices and antigen location in infected duck tissues.

    PubMed

    Yan, Bin; Cheng, An-Chun; Wang, Ming-Shu; Deng, Shu-Xuan; Zhang, Zhen-Hua; Yin, Nian-Chun; Cao, Ping; Cao, Sheng-Yan

    2008-02-07

    To detect Salmonella enteritidis (S. enteritidis) in paraffin slices and antigen location in infected duck tissues. The rabbits were immunized with purified bacillus to obtain S. enteritidis-specific antibody, which were then extracted by the caprylic-ammonium sulphate method, purified through High-Q columns. An indirect immuno-fluorescent staining method (IFA) was established to detect the S. enteritidis antigen in paraffin slices. Detected S. enteritidis in each organ tissue of ducklings experimentally infected with S. enteritidis. The gland of Garder, heart, kidney, spleen, liver, brain, ileum, jejunum, bursa of Fabricius from S. enteritidis experimentally infected ducklings were positive or strongly positive, and the S. enteritidis antigen mainly distributed in the infected cell cytoplasm. IFA is an intuitionist, sensitive and specific method in detecting S. enteritidis antigen in paraffin wax slices, and it is a good method in diagnosis and antigen location of S. enteritidis. We also conclude that the gland of Garder, heart, kidney, spleen, liver, ileum, jejunum are target organs in S. enteritidis infections of duck, and S. enteritidis is an intracellular parasitic bacterium.

  3. Evaluation of indirect drug susceptibility testing using the MODS assay for the detection of XDR-TB in China.

    PubMed

    Huang, Z-K; Luo, Q; Xiong, G-L; Li, W-T; Xu, X-M; Li, J-M

    2014-04-01

    The First Affiliated Hospital of Nanchang University and the Chest Hospital of Jiangxi Province, Jiangxi, China. To assess the performance and feasibility of the microscopic observation drug susceptibility (MODS) assay for the simultaneous detection of multidrug-resistant (MDR) and extensively drug-resistant tuberculosis (XDR-TB) in a high-burden, resource-limited setting. A total of 208 archived clinical isolates of Mycobacterium tuberculosis were used to compare MODS with the conventional proportion method for the rapid detection of resistance to rifampicin (RMP) and isoniazid (INH), as well as to the second-line drugs ofloxacin (OFX) and kanamycin (KM). Sensitivity was respectively 94.5%, 91%, 96.2% and 91.5% for RMP, INH, OFX and KM, and specificity was respectively 97.5%, 96%, 100% and 98.7%. Results for MODS were obtained in a median time of 7 days (range 5-17). The MODS assay offers a simple, rapid, economical and feasible method for the detection of M. tuberculosis resistance to first- and second-line drugs in resource-limited settings.

  4. Indirect decentralized repetitive control

    NASA Technical Reports Server (NTRS)

    Lee, Soo Cheol; Longman, Richard W.

    1993-01-01

    Learning control refers to controllers that learn to improve their performance at executing a given task, based on experience performing this specific task. In a previous work, the authors presented a theory of indirect decentralized learning control based on use of indirect adaptive control concepts employing simultaneous identification and control. This paper extends these results to apply to the indirect repetitive control problem in which a periodic (i.e., repetitive) command is given to a control system. Decentralized indirect repetitive control algorithms are presented that have guaranteed convergence to zero tracking error under very general conditions. The original motivation of the repetitive control and learning control fields was learning in robots doing repetitive tasks such as on an assembly line. This paper starts with decentralized discrete time systems, and progresses to the robot application, modeling the robot as a time varying linear system in the neighborhood of the desired trajectory. Decentralized repetitive control is natural for this application because the feedback control for link rotations is normally implemented in a decentralized manner, treating each link as if it is independent of the other links.

  5. A Simple Ultrasonic Experiment Using a Phase Shift Detection Technique.

    ERIC Educational Resources Information Center

    Yunus, W. Mahmood Mat; Ahmad, Maulana

    1996-01-01

    Describes a simple ultrasonic experiment that can be used to measure the purity of liquid samples by detecting variations in the velocity of sound. Uses a phase shift detection technique that incorporates the use of logic gates and a piezoelectric transducer. (JRH)

  6. A Simple Ultrasonic Experiment Using a Phase Shift Detection Technique.

    ERIC Educational Resources Information Center

    Yunus, W. Mahmood Mat; Ahmad, Maulana

    1996-01-01

    Describes a simple ultrasonic experiment that can be used to measure the purity of liquid samples by detecting variations in the velocity of sound. Uses a phase shift detection technique that incorporates the use of logic gates and a piezoelectric transducer. (JRH)

  7. A novel indirect ELISA based on glycoprotein Gn for the detection of IgG antibodies against Rift Valley fever virus in small ruminants.

    PubMed

    Jäckel, S; Eiden, M; Balkema-Buschmann, A; Ziller, M; van Vuren, P Jansen; Paweska, J T; Groschup, M H

    2013-10-01

    Rift Valley fever virus (RVFV) is an emerging zoonotic pathogen that causes high morbidity and mortality in humans and livestock. In this paper, we describe the cloning, expression and purification of RVFV glycoprotein Gn and its application as a diagnostic antigen in an indirect ELISA for the specific detection of RVF IgG antibodies in sheep and goats. The performance of this Gn based ELISA is validated using a panel of almost 2000 field samples from sheep and goats from Mozambique, Senegal, Uganda and Yemen. All serum samples were also tested by virus neutralization test (VNT), the gold standard method for RVFV serological testing. Compared to the VNT results the Gn based ELISA proved to have an excellent sensitivity (94.56%) and specificity (95.57%). Apart from establishing this new diagnostic assay, these results also demonstrate a close correlation between the presence of RVFV Gn and neutralizing antibodies.

  8. Development of an indirect enzyme-linked immunosorbent assay for the detection of leptospiral antibodies in dogs.

    PubMed

    Ribotta, M J; Higgins, R; Gottschalk, M; Lallier, R

    2000-01-01

    Serology plays an important role in the diagnosis of leptospirosis. Few laboratories have the resources, expertise, or facilities to perform the microscopic agglutination test (MAT). Thus, there is a need for a rapid and simple serological test that could be used in any diagnostic laboratory. In this study, a genus-specific, heat-stable antigenic preparation from Leptospira interrogans serovar pomona was used in an enzyme-linked immunosorbent assay (ELISA) for the detection of leptospiral antibodies in dog sera. This antigenic preparation reacted with rabbit antisera against L. interrogans serovars bratislava, autumnalis, icterohaemorrhagiae and pomona and with rabbit antiserum against L. kirschneri serovar grippotyphosa. The ELISA showed a relative specificity of 95.6% with 158 dog sera which were negative at a dilution of 1:100 in the MAT for serovars pomona, bratislava, icterohaemorrhagiae, autumnalis, hardjo, and grippotyphosa. The relative sensitivity of this assay with 21 dog sera that revealed serovars MAT titres of > or =100 to different serovars was 100%. This assay is easily standardized, technically more advantageous than MAT, and uses an antigenic preparation that can be routinely prepared in large amounts. It was concluded that this ELISA is sufficiently sensitive test to be used as an initial screening test for the detection of leptospiral antibodies in canine sera, with subsequent confirmation of positive test results with the MAT.

  9. Development of an indirect enzyme-linked immunosorbent assay for the detection of leptospiral antibodies in dogs.

    PubMed Central

    Ribotta, M J; Higgins, R; Gottschalk, M; Lallier, R

    2000-01-01

    Serology plays an important role in the diagnosis of leptospirosis. Few laboratories have the resources, expertise, or facilities to perform the microscopic agglutination test (MAT). Thus, there is a need for a rapid and simple serological test that could be used in any diagnostic laboratory. In this study, a genus-specific, heat-stable antigenic preparation from Leptospira interrogans serovar pomona was used in an enzyme-linked immunosorbent assay (ELISA) for the detection of leptospiral antibodies in dog sera. This antigenic preparation reacted with rabbit antisera against L. interrogans serovars bratislava, autumnalis, icterohaemorrhagiae and pomona and with rabbit antiserum against L. kirschneri serovar grippotyphosa. The ELISA showed a relative specificity of 95.6% with 158 dog sera which were negative at a dilution of 1:100 in the MAT for serovars pomona, bratislava, icterohaemorrhagiae, autumnalis, hardjo, and grippotyphosa. The relative sensitivity of this assay with 21 dog sera that revealed serovars MAT titres of > or =100 to different serovars was 100%. This assay is easily standardized, technically more advantageous than MAT, and uses an antigenic preparation that can be routinely prepared in large amounts. It was concluded that this ELISA is sufficiently sensitive test to be used as an initial screening test for the detection of leptospiral antibodies in canine sera, with subsequent confirmation of positive test results with the MAT. PMID:10680654

  10. [Comparison of the indirect immunofluorescent (IFAT), ELISA test and the comercial Chagatek test for anti-Trypanosoma cruzi antibodies detection].

    PubMed

    Enciso, Clara; Montilla, Marleny; Santacruz, María M; Nicholls, Rubén Santiago; Rodríguez, Adriana; Mercado, Marcela; Puerta, Concepción

    2004-03-01

    Chagas disease is a public health problem in Colombia, particularly in the eastern region. Because of human migration from rural areas to urban centers, the possibility of transfusional transmission becomes increasingly important. However the risk can be minimized by a careful screening of blood donors by means of serological tests. Colombian blood banks use comercial, foreign serological tests for screening for T. cruzi infection. The purpose of the current study was to compare the IFAT and ELISA tests (both use antigen obtained from Colombian strains) with the comercially available Chagatek tests. Sera of blood donors were classified in two groups on the basis of the IFAT: group I, 15 positive patients and group II, 14 negative patients. Sera from each group were tested by the ELISA and Chagatek tests. The ELISA test detected 100% of the patients as positive in group I and 7% (1/14) of patients as positive in group II. The Chagatek test detected 93% (14/15) of the patients as positive in group I and 50% (7/14) in group II. The kappa index for concordance between the ELISA and IFAT tests was 0.93 (95% C.I.: 0.80-1.00); between IFAT and Chagatek 0.43 (95% C.I.: 0.26-0.62), and between ELISA and Chagatek 0.49 (95% C.I.: 0.31-0.67). These results highlighted the importance of using autochtonous Colombian strains as antigens in screening tests for blood donors.

  11. Modified Indirect Porcine Circovirus (PCV) Type 2-Based and Recombinant Capsid Protein (ORF2)-Based Enzyme-Linked Immunosorbent Assays for Detection of Antibodies to PCV

    PubMed Central

    Nawagitgul, Porntippa; Harms, Perry A.; Morozov, Igor; Thacker, Brad J.; Sorden, Steven D.; Lekcharoensuk, Chalermpol; Paul, Prem S.

    2002-01-01

    Postweaning multisystemic wasting syndrome of swine associated with porcine circovirus (PCV) is a recently reported and economically important disease. Simple and reliable diagnostic methods are needed for detecting antibodies to PCV type 2 (PCV2) for monitoring of PCV infection. Here, we report the development of two modified indirect enzyme-linked immunosorbent assays (ELISAs): a PCV2 ELISA based on cell-culture-propagated PCV2 and an ORF2 ELISA based on recombinant major capsid protein. PCV2 and ORF2 ELISA detected antibodies to PCV2 and the capsid protein, respectively, in sera from pigs experimentally infected with PCV2 as early as 14 and 21 days postinoculation (dpi). The kinetics of the antibody response to PCV2 and the major capsid protein were similar. Repeatability tests revealed that the coefficients of variation of positive sera within and between runs for both assays were less than 30%. To validate the assays, PCV2 and ORF2 ELISAs were performed with 783 serum samples of young and adult pigs collected from different herds in the Midwestern United States and compared with an indirect immunofluorescent assay (IIF). Six out of 60 samples collected from nursery and growing pigs in 1987 were positive by both ELISA and IIF. Compared with IIF, the diagnostic sensitivity, specificity, and accuracy of PCV2 and ORF2 ELISAs were similar (>90%). The tests showed no cross-reactivity with antibodies to porcine parvovirus and porcine reproductive and respiratory syndrome virus. There was good agreement between the two ELISAs and between the ELISAs and IIF. The availability of the two ELISAs should accelerate our understanding of the host immune response to PCV2 and facilitate the development of prevention and control strategies by elucidating the ecology of PCV2 within swine populations. PMID:11777826

  12. [Multicenter evaluation of the indirect nitrate reductase assay for the rapid detection of multidrug-resistant tuberculosis].

    PubMed

    Çoban, Ahmet Yılmaz; Taştekin, Berika; Uzun, Meltem; Kalaycı, Fatma; Ceyhan, İsmail; Biçmen, Can; Albay, Ali; Sığ, Ali Korhan; Özkütük, Nuri; Sürücüoğlu, Süheyla; Özkütük, Aydan; Esen, Nuran; Albayrak, Nurhan; Aslantürk, Ahmet; Sarıbaş, Zeynep; Alp, Alparslan

    2016-01-01

    Multidrug-resistant tuberculosis (MDR-TB) is defined as resistance to at least isoniazid (INH) and rifampicin (RIF), and it complicates the implementation of tuberculosis control programmes. The rapid detection of MDR-TB is crucial to reduce the transmission of disease. The nitrate reductase assay (NRA) is one of the colorimetric susceptibility test methods for rapid detection of MDR-TB and based on the ability of reduction of nitrate to nitrite by Mycobacterium tuberculosis. The aim of this study was to evaluate the performance of the NRA for the rapid detection of MDR-TB. A total of 237 M.tuberculosis complex (MTC) isolates that were identified by the same method (BD MGIT(TM) TBc Identification Test, USA) from nine different medical centers in Turkey were included in the study. The susceptibility results of the isolates against INH and RIF obtained by reference test (Bactec MGIT(TM) 960, BD, USA) were then compared with NRA. In order to ensure consistency between centers, Löwenstein-Jensen (LJ) medium with antibiotics and without antibiotics (growth control) and Griess reagent solution were prepared in a single center (Ondokuz Mayıs University School of Medicine, Medical Microbiology Department) and sent to all participant centers with the standardized test procedure. After the inoculation of bacteria into the test tubes, the tubes were incubated at 37°C, and after seven days of incubation, 500 μl Griess reagent was added to the LJ medium without antibiotics. If a color change was observed, an equal volume of Griess reagent was added to test LJ media with antibiotics. When a color change was observed in LJ media with antibiotics, it was considered that the isolate was resistant to tested antibiotics. Among 237 MTC isolates, 16 were resistant only to INH and nine were resistant only to RIF; 93 isolates (39.2%) were resistant (MDR) and 119 isolates (50.2%) were susceptible to both of the drugs determined with the reference susceptibility test. In the study

  13. Detection of antibodies specific for sheeppox and goatpox viruses using recombinant capripoxvirus antigens in an indirect enzyme-linked immunosorbent assay.

    PubMed

    Bowden, Timothy R; Coupar, Barbara E; Babiuk, Shawn L; White, John R; Boyd, Victoria; Duch, Christine J; Shiell, Brian J; Ueda, Norihito; Parkyn, Geoff R; Copps, John S; Boyle, David B

    2009-10-01

    Viruses in the genus Capripoxvirus, family Poxviridae, cause sheeppox, goatpox and lumpy skin disease, which are the most serious poxvirus diseases of production animals. Despite the considerable threat that these viruses pose to livestock production and global trade in sheep, goats, cattle and their products, convenient and effective serodiagnostic tools are not readily available. To develop a more effective antibody detection capability, selected open reading frames from capripoxvirus DNA were amplified and expressed in Escherichia coli as His-tagged fusion proteins. By screening 42 candidate antigens, two sheeppox virus virion core proteins that were expressed efficiently, purified readily using affinity chromatography and reactive against capripoxvirus immune sera in an indirect enzyme-linked immunosorbent assay (ELISA) were identified. The ELISA performed favourably when sera from sheep and goats infected experimentally with virulent capripoxvirus isolates were tested, with sensitivity and diagnostic specificity ranging between 95 and 97%, but it was unable to detect antibodies reliably in vaccinated sheep or goats. Furthermore, no cross-reactivity with antibodies against orf virus was detected. This assay offers the prospect of a convenient and standardised ELISA-based serodiagnostic test, with no requirement for infectious reagents, that is well suited to high-throughput capripoxvirus surveillance on a flock or herd basis.

  14. 13C-detected NMR experiments for measuring chemical shifts and coupling constants in nucleic acid bases.

    PubMed

    Fiala, Radovan; Sklenár, Vladimír

    2007-10-01

    The paper presents a set of two-dimensional experiments that utilize direct (13)C detection to provide proton-carbon, carbon-carbon and carbon-nitrogen correlations in the bases of nucleic acids. The set includes a (13)C-detected proton-carbon correlation experiment for the measurement of (13)C-(13)C couplings, the CaCb experiment for correlating two quaternary carbons, the HCaCb experiment for the (13)C-(13)C correlations in cases where one of the carbons has a proton attached, the HCC-TOCSY experiment for correlating a proton with a network of coupled carbons, and a (13)C-detected (13)C-(15)N correlation experiment for detecting the nitrogen nuclei that cannot be detected via protons. The IPAP procedure is used for extracting the carbon-carbon couplings and/or carbon decoupling in the direct dimension, while the S(3)E procedure is preferred in the indirect dimension of the carbon-nitrogen experiment to obtain the value of the coupling constant. The experiments supply accurate values of (13)C and (15)N chemical shifts and carbon-carbon and carbon-nitrogen coupling constants. These values can help to reveal structural features of nucleic acids either directly or via induced changes when the sample is dissolved in oriented media.

  15. Influence of Aerosols on the Shortwave Cloud Radiative Forcing from North Pacific Oceanic Clouds: Results from the Cloud Indirect Forcing Experiment (CIFEX)

    NASA Technical Reports Server (NTRS)

    Wilcox, Eric M.; Roberts, Greg; Ramanathan, V.

    2007-01-01

    Aerosols over the Northeastern Pacific Ocean enhance the cloud drop number concentration and reduce the drop size for marine stratocumulus and cumulus clouds. These microphysical effects result in brighter clouds, as evidenced by a combination of aircraft and satellite observations. In-situ measurements from the Cloud Indirect Forcing Experiment (CIFEX) indicate that the mean cloud drop number concentration in low clouds over the polluted marine boundary layer is greater by 53 cm(sup -3) compared to clean clouds, and the mean cloud drop effective radius is smaller by 4 micrometers. We link these in-situ measurements of cloud modification by aerosols, for the first time, with collocated satellite broadband radiative flux observations from the Clouds and the Earth s Radiant Energy System to show that these microphysical effects of aerosols enhance the top-of-atmosphere cooling by -.9.9 plus or minus 4.3 W m(sup -2) for overcast conditions.

  16. Influence of Aerosols on the Shortwave Cloud Radiative Forcing from North Pacific Oceanic Clouds: Results from the Cloud Indirect Forcing Experiment (CIFEX)

    NASA Technical Reports Server (NTRS)

    Wilcox, Eric M.; Roberts, Greg; Ramanathan, V.

    2007-01-01

    Aerosols over the Northeastern Pacific Ocean enhance the cloud drop number concentration and reduce the drop size for marine stratocumulus and cumulus clouds. These microphysical effects result in brighter clouds, as evidenced by a combination of aircraft and satellite observations. In-situ measurements from the Cloud Indirect Forcing Experiment (CIFEX) indicate that the mean cloud drop number concentration in low clouds over the polluted marine boundary layer is greater by 53 cm(sup -3) compared to clean clouds, and the mean cloud drop effective radius is smaller by 4 micrometers. We link these in-situ measurements of cloud modification by aerosols, for the first time, with collocated satellite broadband radiative flux observations from the Clouds and the Earth s Radiant Energy System to show that these microphysical effects of aerosols enhance the top-of-atmosphere cooling by -.9.9 plus or minus 4.3 W m(sup -2) for overcast conditions.

  17. The Influence of Aerosols on the Shortwave Cloud Radiative Forcing from North Pacific Oceanic Clouds: Results from the Cloud Indirect Forcing Experiment (CIFEX)

    NASA Technical Reports Server (NTRS)

    Wilcox, Eric M.; Roberts, Greg; Ramanathan, V.

    2006-01-01

    Aerosols over the Northeastern Pacific Ocean enhance the cloud drop number concentration and reduce the drop size for marine stratocumulus and cumulus clouds. These microphysical effects result in brighter clouds, as evidenced by a combination of aircraft and satellite observations. In-situ measurements from the Cloud Indirect Forcing Experiment (CIFEX) indicate that the mean cloud drop number concentration in low clouds over the polluted marine boundary layer is greater by 53/cu cm compared to clean clouds, and the mean cloud drop effective radius is smaller by 4 microns. We link these in-situ measurements of cloud modification by aerosols, for the first time, with collocated satellite broadband radiative flux observations from the Clouds and the Earth's Radiant Energy System (CERES) to show that these microphysical effects of aerosols enhance the top-of-atmosphere cooling by -9.9+/-4.3 W/sq m for overcast conditions.

  18. A Low Frequency Electromagnetic Sensor for Indirect Measurement of Glucose Concentration: In Vitro Experiments in Different Conductive Solutions

    PubMed Central

    Tura, Andrea; Sbrignadello, Stefano; Cianciavicchia, Domenico; Pacini, Giovanni; Ravazzani, Paolo

    2010-01-01

    In recent years there has been considerable interest in the study of glucose-induced dielectric property variations of human tissues as a possible approach for non-invasive glycaemia monitoring. We have developed an electromagnetic sensor, and we tested in vitro its ability to estimate variations in glucose concentration of different solutions with similarities to blood (sodium chloride and Ringer-lactate solutions), differing though in the lack of any cellular components. The sensor was able to detect the effect of glucose variations over a wide range of concentrations (∼78–5,000 mg/dL), with a sensitivity of ∼0.22 mV/(mg/dL). Our proposed system may thus be useful in a new approach for non-invasive and non-contact glucose monitoring. PMID:22219665

  19. A low frequency electromagnetic sensor for indirect measurement of glucose concentration: in vitro experiments in different conductive solutions.

    PubMed

    Tura, Andrea; Sbrignadello, Stefano; Cianciavicchia, Domenico; Pacini, Giovanni; Ravazzani, Paolo

    2010-01-01

    In recent years there has been considerable interest in the study of glucose-induced dielectric property variations of human tissues as a possible approach for non-invasive glycaemia monitoring. We have developed an electromagnetic sensor, and we tested in vitro its ability to estimate variations in glucose concentration of different solutions with similarities to blood (sodium chloride and Ringer-lactate solutions), differing though in the lack of any cellular components. The sensor was able to detect the effect of glucose variations over a wide range of concentrations (∼78-5,000 mg/dL), with a sensitivity of ∼0.22 mV/(mg/dL). Our proposed system may thus be useful in a new approach for non-invasive and non-contact glucose monitoring.

  20. Prospects for indirect MeV dark matter detection with gamma rays in light of cosmic microwave background constraints

    NASA Astrophysics Data System (ADS)

    González-Morales, Alma X.; Profumo, Stefano; Reynoso-Cordova, Javier

    2017-09-01

    The self-annihilation of dark matter particles with mass in the MeV range can produce gamma rays via prompt or secondary radiation. The annihilation rate for such light dark matter particles is however tightly constrained by cosmic microwave background (CMB) data. Here we explore the possibility of discovering MeV dark matter annihilation with future MeV gamma-ray telescopes taking into account the latest and future CMB constraints. We study the optimal energy window as a function of the dominant annihilation final state. We consider both the (conservative) case of the dwarf spheroidal galaxy Draco and the (more optimistic) case of the Galactic center. We find that for certain channels, including those with one or two monochromatic photon(s) and one or two neutral pion(s), a detectable gamma-ray signal is possible for both targets under consideration and compatible with CMB constraints. For other annihilation channels, however, including all leptonic annihilation channels and two charged pions, CMB data rule out any significant signal of dark matter annihilation at future MeV gamma-ray telescopes from dwarf galaxies, but possibly not for the Galactic center.

  1. Comparative investigation of the detective quantum efficiency of direct and indirect conversion detector technologies in dedicated breast CT.

    PubMed

    Kuttig, Jan D; Steiding, Christian; Kolditz, Daniel; Hupfer, Martin; Karolczak, Marek; Kalender, Willi A

    2015-06-01

    To investigate the dose saving potential of direct-converting CdTe photon-counting detector technology for dedicated breast CT. We analyzed the modulation transfer function (MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE) of two detector technologies, suitable for breast CT (BCT): a flat-panel energy-integrating detector with a 70 μm and a 208 μm thick gadolinium oxysulfide (GOS) and a 150 μm thick cesium iodide (CsI) scintillator and a photon-counting detector with a 1000 μm thick CdTe sensor. The measurements for GOS scintillator thicknesses of 70 μm and 208 μm delivered 10% pre-sampled MTF values of 6.6 mm(-1) and 3.2 mm(-1), and DQE(0) values of 23% and 61%. The 10% pre-sampled MTF value for the 150 μm thick CsI scintillator 6.9 mm(-1), and the DQE(0) value was 49%. The CdTe sensor reached a 10% pre-sampled MTF value of 8.5 mm(-1) and a DQE(0) value of 85%. The photon-counting CdTe detector technology allows for significant dose reduction compared to the energy-integrating scintillation detector technology used in BCT today. Our comparative evaluation indicates that a high potential dose saving may be possible for BCT by using CdTe detectors, without loss of spatial resolution. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  2. Detection of African Swine Fever Virus Antibodies in Serum and Oral Fluid Specimens Using a Recombinant Protein 30 (p30) Dual Matrix Indirect ELISA.

    PubMed

    Giménez-Lirola, Luis G; Mur, Lina; Rivera, Belen; Mogler, Mark; Sun, Yaxuan; Lizano, Sergio; Goodell, Christa; Harris, D L Hank; Rowland, Raymond R R; Gallardo, Carmina; Sánchez-Vizcaíno, José Manuel; Zimmerman, Jeff

    2016-01-01

    In the absence of effective vaccine(s), control of African swine fever caused by African swine fever virus (ASFV) must be based on early, efficient, cost-effective detection and strict control and elimination strategies. For this purpose, we developed an indirect ELISA capable of detecting ASFV antibodies in either serum or oral fluid specimens. The recombinant protein used in the ELISA was selected by comparing the early serum antibody response of ASFV-infected pigs (NHV-p68 isolate) to three major recombinant polypeptides (p30, p54, p72) using a multiplex fluorescent microbead-based immunoassay (FMIA). Non-hazardous (non-infectious) antibody-positive serum for use as plate positive controls and for the calculation of sample-to-positive (S:P) ratios was produced by inoculating pigs with a replicon particle (RP) vaccine expressing the ASFV p30 gene. The optimized ELISA detected anti-p30 antibodies in serum and/or oral fluid samples from pigs inoculated with ASFV under experimental conditions beginning 8 to 12 days post inoculation. Tests on serum (n = 200) and oral fluid (n = 200) field samples from an ASFV-free population demonstrated that the assay was highly diagnostically specific. The convenience and diagnostic utility of oral fluid sampling combined with the flexibility to test either serum or oral fluid on the same platform suggests that this assay will be highly useful under the conditions for which OIE recommends ASFV antibody surveillance, i.e., in ASFV-endemic areas and for the detection of infections with ASFV isolates of low virulence.

  3. Detection of African Swine Fever Virus Antibodies in Serum and Oral Fluid Specimens Using a Recombinant Protein 30 (p30) Dual Matrix Indirect ELISA

    PubMed Central

    Giménez-Lirola, Luis G.; Mur, Lina; Rivera, Belen; Mogler, Mark; Sun, Yaxuan; Lizano, Sergio; Goodell, Christa; Harris, D. L. Hank; Rowland, Raymond R. R.; Gallardo, Carmina; Sánchez-Vizcaíno, José Manuel; Zimmerman, Jeff

    2016-01-01

    In the absence of effective vaccine(s), control of African swine fever caused by African swine fever virus (ASFV) must be based on early, efficient, cost-effective detection and strict control and elimination strategies. For this purpose, we developed an indirect ELISA capable of detecting ASFV antibodies in either serum or oral fluid specimens. The recombinant protein used in the ELISA was selected by comparing the early serum antibody response of ASFV-infected pigs (NHV-p68 isolate) to three major recombinant polypeptides (p30, p54, p72) using a multiplex fluorescent microbead-based immunoassay (FMIA). Non-hazardous (non-infectious) antibody-positive serum for use as plate positive controls and for the calculation of sample-to-positive (S:P) ratios was produced by inoculating pigs with a replicon particle (RP) vaccine expressing the ASFV p30 gene. The optimized ELISA detected anti-p30 antibodies in serum and/or oral fluid samples from pigs inoculated with ASFV under experimental conditions beginning 8 to 12 days post inoculation. Tests on serum (n = 200) and oral fluid (n = 200) field samples from an ASFV-free population demonstrated that the assay was highly diagnostically specific. The convenience and diagnostic utility of oral fluid sampling combined with the flexibility to test either serum or oral fluid on the same platform suggests that this assay will be highly useful under the conditions for which OIE recommends ASFV antibody surveillance, i.e., in ASFV-endemic areas and for the detection of infections with ASFV isolates of low virulence. PMID:27611939

  4. Effects of blood contamination of cerebrospinal fluid on results of indirect fluorescent antibody tests for detection of antibodies against Sarcocystis neurona and Neospora hughesi.

    PubMed

    Finno, Carrie J; Packham, Andrea E; David Wilson, W; Gardner, Ian A; Conrad, Patricia A; Pusterla, Nicola

    2007-05-01

    The purpose of this study was to determine the effect of blood contamination of cerebrospinal fluid (CSF) on the results of indirect fluorescent antibody tests (IFATs) for Sarcocystis neurona and Neospora hughesi. The in vitro study used antibody-negative CSF collected from non-neurologic horses immediately after euthanasia and blood samples from 40 healthy horses that had a range of IFAT antibody titers against S. neurona and N. hughesi. Serial dilutions of whole blood were made in seronegative CSF to generate blood-contaminated CSF with red blood cell (RBC) concentrations ranging from 10 to 100,000 RBCs/microl. The blood-contaminated CSF samples were then tested for antibodies against both pathogens using IFAT. Blood contamination of CSF had no detectable effect on IFAT results for S. neurona or N. hughesi at any serologic titer when the RBC concentration in CSF was <10,000 RBCs/microl. At concentrations of 10,000-100,000 RBCs/microl of CSF, positive CSF results (IFAT titer >or=5) for S. neurona and N. hughesi were detected only when the corresponding serum titers were >or=160 and >or=80, respectively. The IFAT performed on CSF is reliable for testing horses for equine protozoal myeloencephalitis caused by S. neurona or N. hughesi, even when blood contamination causes the RBC concentration in CSF to be up to 10,000 RBCs/microl.

  5. Colloidal gold-based indirect competitive immunochromatographic assay for rapid detection of bioactive isoflavone glycosides daidzin and genistin in soy products.

    PubMed

    Sakamoto, Seiichi; Yusakul, Gorawit; Pongkitwitoon, Benyakan; Tanaka, Hiroyuki; Morimoto, Satoshi

    2016-03-01

    Daidzin (DZ) and genistin (GEN) are two major soy isoflavone glycosides isolated from soybeans. Soy products containing isoflavones have recently been widely accepted for commercial use. However, the Japanese Government has suggested that soy isoflavone intake should be limited because of their estrogenic effects due to their interactions with estrogen receptors. In this study, we established a one-step indirect competitive immunochromatographic assay (ICA) for rapid and sensitive detection of total isoflavone glycosides (DZ and GEN) using gold nanoparticles conjugated with a monoclonal antibody against DZ. This assay was able to be completed in 15min following the immersion of a test strip in an analyte solution. Furthermore, the limit of detection for the total amount of isoflavone glycosides was ∼125ngmL(-1). Considering that the major soy isoflavone glycosides found in soy products are DZ and GEN, this study demonstrates the potential use of ICA for the assessments of over consumption of isoflavones in soy supplements and foods, which would increase the safe dietary intake of soy products.

  6. Development and application of a recombinant M protein-based indirect ELISA for the detection of porcine deltacoronavirus IgG antibodies.

    PubMed

    Luo, Shang-Xing; Fan, Jing-Hui; Opriessnig, Tanja; Di, Jing-Mei; Liu, Bao-Jing; Zuo, Yu-Zhu

    2017-08-30

    Porcine deltacoronavirus (PDCoV) is a recently identified coronavirus in the genus Deltacoronavirus that can cause enteric disease including diarrhea, vomiting, dehydration and mortality in neonatal piglets. Serological assays to detect anti-PDCoV antibodies are presently limited to certain laboratories and geographic regions. In this study, a recombinant M protein-based indirect enzyme-linked immunosorbent assay (PDCoV-rM ELISA) was developed and utilized to determine the prevalence of anti-PDCoV IgG in Hebei province. The PDCoV-rM ELISA showed no cross-reaction with antisera against transmissible gastroenteritis virus (TGEV), porcine epidemic diarrhea virus (PEDV), porcine rotavirus (PRV), porcine circovirus 2 (PCV2), classical swine fever virus (CSFV) or porcine reproductive and respiratory syndrome virus (PRRSV). The diagnostic sensitivity was 90.6% and the diagnostic specificity was 93.3%. A total of 871 serum samples collected in Hebei from January 2015 to October 2016 were checked for presence of antibodies against PDCoV using the novel PDCoV-rM ELISA. Anti-PDCoV IgG antibodies were detected in 11% (96/871) of the samples and in 25% (10/40) of the investigated farms. The data suggest that PDCoV has a low seroprevalence in pig population in Hebei province, China. Copyright © 2017. Published by Elsevier B.V.

  7. Detection of cross-reactive antigens shared by Fusarium oxysporum and Glycine max by indirect ELISA and their cellular location in root tissues.

    PubMed

    Chakraborty, B N; Sarkar, B; Chakraborty, U

    1997-01-01

    Pathogenicity test of Fusarium oxysporum on ten cultivars of soybean revealed Soymax and Punjab-1 to be most resistant while JS-2 and UPSM-19 were most susceptible. Antigens were prepared from the roots of all the ten varieties of soybean and the mycelium of F. oxysporum. Polyclonal antisera were raised against the mycelial suspension of F. oxysporum and the root antigen of the susceptible cultivar UPSM-19. Cross reactive antigens shared by the host and the pathogen were detected first by immunodiffusion. The immunoglobulin fraction of the antiserum was purified by ammonium sulfate precipitation and DEAE-Sephadex column chromatography. The immunoglobulin fractions were used for detection of cross-reactive antigens by enzyme-linked immunosorbent assay. In enzyme-linked immunosorbent assay, antigens of susceptible cultivars showed higher absorbance values when tested against the purified anti-F. oxysporum antiserum. Antiserum produced against UPSM-19 showed cross-reactivity with the antigens of other cultivars. Indirect staining of antibodies using fluorescein isothiocyanate indicated that in cross-sections of roots of susceptible cultivar (UPSM-19) cross-reactive antigens were concentrated around xylem elements, endodermis and epidermal cells, while in the resistant variety, fluorescence was concentrated mainly around epidermal cells and distributed in the cortical tissues. CRAs were also present in microconidia, macroconidia and chlamydospores of the fungus.

  8. An indirect immunofluorescence assay using a cell culture-derived antigen for detection of antibodies to the agent of human granulocytic ehrlichiosis.

    PubMed Central

    Nicholson, W L; Comer, J A; Sumner, J W; Gingrich-Baker, C; Coughlin, R T; Magnarelli, L A; Olson, J G; Childs, J E

    1997-01-01

    An indirect immunofluorescence assay for the detection of human antibodies to the agent of human granulocytic ehrlichiosis (HGE) was developed and standardized. Antigen was prepared from a human promyelocytic leukemia cell line (HL-60) infected with a tick-derived isolate of the HGE agent (USG3). Suitable antigen presentation and preservation of cellular morphology were obtained when infected cells were applied and cultured on the slide, excess medium was removed, and cells were fixed with acetone. Use of a buffer containing bovine serum albumin and goat serum reduced background fluorescence, and use of an immunoglobulin G (gamma-specific) conjugate reduced nonspecific binding. The assay readily detected specific antibody from HGE patients and did not detect antibody from healthy individuals. No significant reactivity was noted in sera from patients with high titers of antibodies to other rickettsial species. We were able to identify antibodies reactive to USG3 antigen in samples from areas where HGE is endemic that had tested negative to other rickettsial agents. Animal sera reactive against Ehrlichia equi or Ehrlichia phagocytophila bound to the HGE antigen, indicating that the assay may be useful for veterinary use. Comparability between two different laboratories was assessed by using coded human sera exchanged between laboratories. Results from the two laboratories were similar, indicating that the assay can be easily integrated into use for routine testing for HGE. The assay was then compared to an assay using horse neutrophils infected with ehrlichiae. The two assays gave comparable results, indicating that the cell culture-derived antigen can be used for testing samples that have been previously tested with E. equi as an antigen. The new assay offers several advantages over other immunofluorescence methods that use animal-derived antigen and is suitable for use in testing for human antibodies to the HGE agent. PMID:9163471

  9. Comparison of shikimic acid determination by capillary zone electrophoresis with direct and indirect detection with liquid chromatography for varietal differentiation of red wines.

    PubMed

    Mardones, Claudia; Hitschfeld, Antonieta; Contreras, Alejandra; Lepe, Karla; Gutiérrez, Luis; von Baer, Dietrich

    2005-09-02

    Two capillary zone electrophoretic (CZE) methods for determination of shikimic acid in Chilean red wine were developed and compared with a HPLC method. Both electrophoretic methods were carried out by using a reversed electroosmotic flow induced by trimethyl(tetradecyl)ammoniumbromide (TTAB) with indirect detection at 260 nm using p-aminobenzoic acid as a UV-absorbing co-ion or by direct detection at 213 nm. In both cases, the separation was carried out in a 50 microm I.D. uncoated capillary with an effective length of 48 cm, a negative power supply of 30 kV, using a buffer based on bis[2-hydroxyethyl]imino-tris[hydroxymethyl]methane (Bis-Tris), pH 7.0 or 7.5 and hydrodynamic injection. The chromatographic separations were carried out on a C-18 reversed phase column followed by a sulfonyl-styrene-divinylbenzene (S-DVB) ion exclusion column at 70 degrees C with H2SO4 0.02 M as isocratic mobile phase and a flow rate of 0.5 mL min(-1). The three methods allowed the quantification of shikimic acid with quantification limits between 1.0 and 12.0 mg L(-1) and precision between 7.3 and 10.1%, however, only the concentrations obtained by CZE with direct detection were statistically similar to those of HPLC. This parameter was evaluated as analytical tool to verify varietal authenticity of red wines. In all cases, the Cabernet Sauvignon wines presented higher concentrations of shikimic acid, compared with Merlot or Carmenère wines.

  10. Greenhouse Effect Detection Experiment (GEDEX). Selected data sets

    NASA Technical Reports Server (NTRS)

    Olsen, Lola M.; Warnock, Archibald, III

    1992-01-01

    This CD-ROM contains selected data sets compiled by the participants of the Greenhouse Effect Detection Experiment (GEDEX) workshop on atmospheric temperature. The data sets include surface, upper air, and/or satellite-derived measurements of temperature, solar irradiance, clouds, greenhouse gases, fluxes, albedo, aerosols, ozone, and water vapor, along with Southern Oscillation Indices and Quasi-Biennial Oscillation statistics.

  11. The design of an experiment to detect low energy antiprotons

    NASA Technical Reports Server (NTRS)

    Lloyd-Evans, J.; Acharya, B. S.; Balasubrahmanyan, V. K.; Ormes, J. F.; Streitmatter, R. E.; Stephens, S. A.

    1985-01-01

    The techniques to be used in a balloon borne experiment APEX to detect 220 MeV antiprotons are described, paying particular attention to potential sources of background. Event time history is shown to be very effective in eliminating this background. Results of laboratory tests on the timing resolution which may be achieved are presented.

  12. Physics from solar neutrinos in dark matter direct detection experiments

    NASA Astrophysics Data System (ADS)

    Cerdeño, David G.; Fairbairn, Malcolm; Jubb, Thomas; Machado, Pedro A. N.; Vincent, Aaron C.; Bœhm, Céline

    2016-05-01

    The next generation of dark matter direct detection experiments will be sensitive to both coherent neutrino-nucleus and neutrino-electron scattering. This will enable them to explore aspects of solar physics, perform the lowest energy measurement of the weak angle sin2 θ W to date, and probe contributions from new theories with light mediators. In this article, we compute the projected nuclear and electron recoil rates expected in several dark matter direct detection experiments due to solar neutrinos, and use these estimates to quantify errors on future measurements of the neutrino fluxes, weak mixing angle and solar observables, as well as to constrain new physics in the neutrino sector. Our analysis shows that the combined rates of solar neutrino events in second generation experiments (SuperCDMS and LZ) can yield a measurement of the pp flux to 2.5% accuracy via electron recoil, and slightly improve the 8B flux determination. Assuming a low-mass argon phase, projected tonne-scale experiments like DARWIN can reduce the uncertainty on both the pp and boron-8 neutrino fluxes to below 1%. Finally, we use current results from LUX, SuperCDMS and CDMSlite to set bounds on new interactions between neutrinos and electrons or nuclei, and show that future direct detection experiments can be used to set complementary constraints on the parameter space associated with light mediators.

  13. Dark matter effective field theory scattering in direct detection experiments

    SciTech Connect

    Schneck, K.; Cabrera, B.; Cerdeño, D. G.; Mandic, V.; Rogers, H. E.; Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Brandt, D.; Brink, P. L.; Bunker, R.; Caldwell, D. O.; Calkins, R.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jardin, D. M.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, P.; Mahapatra, R.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Roberts, A.; Saab, T.; Sadoulet, B.; Sander, J.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Toback, D.; Upadhyayula, S.; Villano, A. N.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yang, X.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2015-05-18

    We examine the consequences of the effective field theory (EFT) of dark matter–nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implications of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.

  14. Dark matter effective field theory scattering in direct detection experiments

    DOE PAGES

    Schneck, K.

    2015-05-01

    We examine the consequences of the effective field theory (EFT) of dark matter–nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implicationsmore » of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.« less

  15. Scalar split WIMPs in future direct detection experiments

    NASA Astrophysics Data System (ADS)

    Ghorbani, Karim; Ghorbani, Hossein

    2016-03-01

    We consider a simple renormalizable dark matter model consisting of two real scalars with a mass splitting δ , interacting with the SM particles through the Higgs portal. We find a viable parameter space respecting all the bounds imposed by invisible Higgs decay experiments at the LHC, the direct detection experiments by XENON100 and LUX, and the dark matter relic abundance provided by WMAP and Planck. Despite the singlet scalar dark matter model that is fragile against the future direct detection experiments, the scalar split model introduced here survives such forthcoming bounds. We emphasize the role of the coannihilation processes and the mixing effects in this feature. For mDM˜63 GeV in this model we can explain as well the observed gamma-ray excess in the analyses of the Fermi-LAT data at Galactic latitudes 2 ° ≤|b |≤2 0 ° and Galactic longitudes |l |<2 0 ° .

  16. Dark matter effective field theory scattering in direct detection experiments

    SciTech Connect

    Schneck, K.; Cabrera, B.; Cerdeno, D. G.; Mandic, V.; Rogers, H. E.; Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Brandt, D.; Brink, P. L.; Bunker, R.; Caldwell, D. O.; Calkins, R.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, Priscilla B.; Daal, M.; Di Stefano, P. C.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, Jeter C.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jardin, D. M.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, W.; Mahapatra, R.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Roberts, A.; Saab, T.; Sadoulet, B.; Sander, J.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Toback, D.; Upadhyayula, S.; Villano, A. N.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yang, X.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2015-05-01

    We examine the consequences of the effective eld theory (EFT) of dark matter-nucleon scattering or current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral di*erences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implications of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.

  17. Dark matter effective field theory scattering in direct detection experiments

    SciTech Connect

    Schneck, K.; Cabrera, B.; Cerdeño, D. G.; Mandic, V.; Rogers, H. E.; Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Brandt, D.; Brink, P. L.; Bunker, R.; Caldwell, D. O.; Calkins, R.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jardin, D. M.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, P.; Mahapatra, R.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Roberts, A.; Saab, T.; Sadoulet, B.; Sander, J.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Toback, D.; Upadhyayula, S.; Villano, A. N.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yang, X.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2015-05-18

    We examine the consequences of the effective field theory (EFT) of dark matter-nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. Here. we demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. In conclusion, we discuss the implications of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.

  18. Dark matter effective field theory scattering in direct detection experiments

    SciTech Connect

    Schneck, K.

    2015-05-01

    We examine the consequences of the effective field theory (EFT) of dark matter–nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implications of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.

  19. Power evaluation of asymptotic tests for comparing two binomial proportions to detect direct and indirect association in large-scale studies.

    PubMed

    Emily, Mathieu; Friguet, Chloé

    2015-10-14

    Asymptotic tests are commonly used for comparing two binomial proportions when the sample size is sufficiently large. However, there is no consensus on the most powerful test. In this paper, we clarify this issue by comparing the power functions of three popular asymptotic tests: the Pearson's χ(2) test, the likelihood-ratio test and the odds-ratio based test. Considering Taylor decompositions under local alternatives, the comparisons lead to recommendations on which test to use in view of both the experimental design and the nature of the investigated signal. We show that when the design is balanced between the two binomials, the three tests are equivalent in terms of power. However, when the design is unbalanced, differences in power can be substantial and the choice of the most powerful test also depends on the value of the parameters of the two compared binomials. We further investigated situations where the two binomials are not compared directly but through tag binomials. In these cases of indirect association, we show that the differences in power between the three tests are enhanced with decreasing values of the parameters of the tag binomials. Our results are illustrated in the context of genetic epidemiology where the analysis of genome-wide association studies provides insights regarding the low power for detecting rare variants.

  20. Determination of polyphosphates in fish and shrimp muscles by capillary electrophoresis with indirect UV detection after phosphatase inhibition using high pressure pretreatment.

    PubMed

    Wang, Li; Li, Juan; Zhang, Li

    2015-10-15

    A method was proposed for the determination of polyphosphates (P2O7(4-), P3O10(5-) and (PO3)3(3-)) in fish and shrimp muscles by capillary electrophoresis with indirect UV detection after phosphatase inhibition using high pressure pretreatment (HPP). Separation parameters were optimized and the effects of HPP on deactivation of enzyme were investigated. Well resolution was obtained with 10 mM adenosine 5'-phosphate (ATP) in 16 mM disodium hydrogen phosphate combining with 32 mM citric acid buffer (pH = 6.4) containing 0.1 mM cetyltrimethyl ammonium bromide, and phosphatase was effectively inhibited by HPP at 400 MPa for 10 min. Method was validated with LOD (0.23-0.33 mg g(-1)) and LOQ (0.77-1.0 mg g(-1)). Recovery of P2O7(4-), P3O10(5-) and (PO3)3(3-) in the fortified samples were in the range of 91.6-100.1%, 97.6-104.6% and 79.1-88.1%, respectively, and the corresponding RSD ranged from 1.1% to 6.8%. Finally, the method was applied in the determination of polyphosphates in food samples collected from local markets.

  1. Microchip CE analysis of amino acids on a titanium dioxide nanoparticles-coated PDMS microfluidic device with in-channel indirect amperometric detection.

    PubMed

    Qiu, Jian-Ding; Wang, Li; Liang, Ru-Ping; Wang, Jing-Wu

    2009-10-01

    In this paper, titanium dioxide nanoparticles (TiO(2) NPs) were employed to construct a functional film on PDMS microfluidic channel surface, which was formed by sequentially immobilizing poly(diallyldimethylammonium chloride) and TiO(2) NPs on PDMS surface by layer-by-layer assembly technique. The modified PDMS microchip exhibited a decreased and stable EOF, which was favorable for the separation of biomolecules with similar migration times. Arginine, phenylalanine, serine and threonine were used as model analytes to evaluate the performance of the modified microchip. The four amino acids were efficiently separated within 100 s in a 3.7 cm long separation channel and successfully detected on the carbon fiber electrode in conjunction with in-channel indirect amperometry. Resolutions and theoretical plate numbers of the analytes were considerably enhanced in the presence of TiO(2) NPs. The modified microchip demonstrated excellent stability and reproducibility with improved RSDs of migration times and peak currents for run-to-run, day-to-day and chip-to-chip analyses, respectively. Variables influencing the separation efficiency and amperometric response, including injection and separation voltage, the working electrode position and buffer concentration, were optimized in detail.

  2. Evaluation of automated multi-parametric indirect immunofluorescence assays to detect anti-neutrophil cytoplasmic antibodies (ANCA) in granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA).

    PubMed

    Csernok, Elena; Damoiseaux, Jan; Rasmussen, Niels; Hellmich, Bernhard; van Paassen, Pieter; Vermeersch, Pieter; Blockmans, Daniel; Cohen Tervaert, Jan-Willem; Bossuyt, Xavier

    2016-07-01

    The aim of this multicenter EUVAS study was to evaluate the diagnostic performance of multi-parametric indirect immunofluorescence (IIF) assays to detect anti-neutrophil cytoplasmic antibodies (ANCA) in granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA). The study included 912 samples from diseased controls and 249 diagnostic samples from GPA (n=183) and MPA (n=66) patients. The performance of two automated multi-parametric assays [Aklides (Medipan/Generic Assays) and EuroPattern (Euroimmun)] combining IIF on cellular and purified antigen substrates was compared with two manual IIF analyses and with commercially available ELISAs for MPO- and PR3-ANCA (Euroimmun). The area under the curve (AUC) of the receiver operating characteristics (ROC) curve to discriminate AAV from controls was 0.925, 0.848, 0.855 and 0.904 for, respectively, the two manual analyses, Aklides and EuroPattern, and 0.959, 0.921 and 0.886 for, respectively, antigen-specific ELISA, antigen-coated beads, and microdot, respectively. Variation in pattern assignment between IIF methods was observed. The performance of IIF depends on the substrate used and the definition of IIF patterns. The performance of automated IIF is improved by multi-parameter testing (combined IIF and antigen-specific testing). Given the variability between IIF methods, the diagnostic importance of this technique is questioned. Copyright © 2016. Published by Elsevier B.V.

  3. Detection of anti-Leishmania infantum antibodies in sylvatic lagomorphs from an epidemic area of Madrid using the indirect immunofluorescence antibody test.

    PubMed

    Moreno, Inmaculada; Álvarez, Julio; García, Nerea; de la Fuente, Santiago; Martínez, Irene; Marino, Eloy; Toraño, Alfredo; Goyache, Joaquin; Vilas, Felipe; Domínguez, Lucas; Domínguez, Mercedes

    2014-01-31

    An outbreak of human leishmaniasis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections.

  4. Development and evaluation of indirect ELISAs for the detection of IgG, IgM and IgA1 against duck hepatitis A virus 1.

    PubMed

    Mao, Sai; Ou, XuMin; Zhu, DeKang; Chen, Shun; Ma, GuangPeng; Wang, MingShu; Jia, RenYong; Liu, MaFeng; Sun, KunFeng; Yang, Qiao; Wu, Ying; Chen, XiaoYue; Cheng, AnChun

    2016-11-01

    Duck hepatitis A virus 1 (DHAV-1) is the principal pathogen that causes duck viral hepatitis (DHV), a highly fatal infectious disease in ducklings. Given the importance of the humoral immune response in the clearance of DHAV-1, indirect enzyme-linked immunosorbent assays (I-ELISAs) to detect immune indices, including IgG, IgM and IgA1, were developed and evaluated in this study. The optimal concentrations of coating-antigen were 1.79μg/ml, 2.23μg/ml and 2.23μg/ml for IgG, IgM and IgA1, respectively. Meanwhile, the optimal dilutions of sera were 1:80, 1:40 and 1:40, respectively; and of the conjugates were 1:300, 1:1800 and 1:800, respectively. Based on these conditions, three linear regression equations, y=1.363+1.954x (r(2)=0.983), y=1.141+2.228x (r(2)=0.970) and y=1.103+1.559x (r(2)=0.995) were derived for IgG, IgM and IgA1, respectively. Analytical sensitivities of the new methods were 1:2560, 1:1280 and 1:640 for IgG, IgM and IgA1, respectively. The concordances between the I-ELISAs and serum-neutralization were 95.2% for IgG and IgA1, and 75% for IgM. Although there was a weak cross-reaction with DHAV-3 positive serum for the IgG and IgA1 tests, it didn't affect the ability to detect DHAV-1 specific antibodies. Thus, these new I-ELISAs were shown to be potentially convenient methods to survey the status of humoral immune response to DHAV-1.

  5. Identification of inorganic improvised explosive devices by analysis of postblast residues using portable capillary electrophoresis instrumentation and indirect photometric detection with a light-emitting diode.

    PubMed

    Hutchinson, Joseph P; Evenhuis, Christopher J; Johns, Cameron; Kazarian, Artaches A; Breadmore, Michael C; Macka, Miroslav; Hilder, Emily F; Guijt, Rosanne M; Dicinoski, Greg W; Haddad, Paul R

    2007-09-15

    A commercial portable capillary electrophoresis (CE) instrument has been used to separate inorganic anions and cations found in postblast residues from improvised explosive devices (IEDs) of the type used frequently in terrorism attacks. The purpose of this analysis was to identify the type of explosive used. The CE instrument was modified for use with an in-house miniaturized light-emitting diode (LED) detector to enable sensitive indirect photometric detection to be employed for the detection of 15 anions (acetate, benzoate, carbonate, chlorate, chloride, chlorite, cyanate, fluoride, nitrate, nitrite, perchlorate, phosphate, sulfate, thiocyanate, thiosulfate) and 12 cations (ammonium, monomethylammonium, ethylammonium, potassium, sodium, barium, strontium, magnesium, manganese, calcium, zinc, lead) as the target analytes. These ions are known to be present in postblast residues from inorganic IEDs constructed from ammonium nitrate/fuel oil mixtures, black powder, and chlorate/perchlorate/sugar mixtures. For the analysis of cations, a blue LED (470 nm) was used in conjunction with the highly absorbing cationic dye, chrysoidine (absorption maximum at 453 nm). A nonaqueous background electrolyte comprising 10 mM chrysoidine in methanol was found to give greatly improved baseline stability in comparison to aqueous electrolytes due to the increased solubility of chrysoidine and its decreased adsorption onto the capillary wall. Glacial acetic acid (0.7% v/v) was added to ensure chrysoidine was protonated and to enhance separation selectivity by means of complexation with transition metal ions. The 12 target cations were separated in less than 9.5 min with detection limits of 0.11-2.30 mg/L (calculated at a signal-to-noise ratio of 3). The anions separation system utilized a UV LED (370 nm) in conjunction with an aqueous chromate electrolyte (absorption maximum at 371 nm) consisting of 10 mM chromium(VI) oxide and 10 mM sodium chromate, buffered with 40 mM tris

  6. Experiments in ultrasonic flaw detection using a MEMS transducer

    NASA Astrophysics Data System (ADS)

    Jain, Akash; Greve, David W.; Oppenheim, Irving J.

    2003-08-01

    In earlier work we developed a MEMS phased array transducer, fabricated in the MUMPs process, and we reported on initial experimental studies in which the device was affixed into contact with solids. We demonstrated the successful detection of signals from a conventional ultrasonic source, and the successful localization of the source in an off-axis geometry using phased array signal processing. We now describe the predicted transmission and coupling characteristics for such devices in contact with solids, demonstrating reasonable agreement with experimental behavior. We then describe the results of flaw detection experiments, as well as results for fluid-coupled detectors.

  7. Optimization of detection sensitivity for a Fiber Optic Intrusion Detection System (FOIDS) using design of experiments.

    SciTech Connect

    Miller, Larry D.; Mack, Thomas Kimball; Mitchiner, Kim W.; Varoz, Carmella A.

    2010-06-01

    The Fiber Optic Intrusion Detection System (FOIDS)1 is a physical security sensor deployed on fence lines to detect climb or cut intrusions by adversaries. Calibration of detection sensitivity can be time consuming because, for example, the FiberSenSys FD-332 has 32 settings that can be adjusted independently to provide a balance between a high probability of detection and a low nuisance alarm rate. Therefore, an efficient method of calibrating the FOIDS in the field, other than by trial and error, was needed. This study was conducted to: x Identify the most significant settings for controlling detection x Develop a way of predicting detection sensitivity for given settings x Develop a set of optimal settings for validation The Design of Experiments (DoE) 2-4 methodology was used to generate small, planned test matrixes, which could be statistically analyzed to yield more information from the test data. Design of Experiments is a statistical methodology for quickly optimizing performance of systems with measurable input and output variables. DoE was used to design custom screening experiments based on 11 FOIDS settings believed to have the most affect on WKH types of fence perimeter intrusions were evaluated: simulated cut intrusions and actual climb intrusions. Two slightly different two-level randomized fractional factorial designed experiment matrixes consisting of 16 unique experiments were performed in the field for each type of intrusion. Three repetitions were conducted for every cut test; two repetitions were conducted for every climb test. Total number of cut tests analyzed was 51; the total number of climb tests was 38. This paper discusses the results and benefits of using Design of Experiments (DoE) to calibrate and optimize the settings for a FOIDS sensor

  8. Full-scale Experiments for Roadbed Cavity Detection with GPR

    NASA Astrophysics Data System (ADS)

    Kim, C.; Kang, W.; Son, J.

    2015-12-01

    Past few decades, deterioration of the underground facilities such as sewage facilities has increased significantly with growing urban development in Korea. The old damaged sewage pipes or conduits have washed away the surrounding soils beneath the roadbed, causing underground cavities and eventual ground depressions or sinkholes in the urban areas. Therefore, the detection of the roadbed cavities is increasingly required to prevent property damage and loss of human lives for precautionary measures. 3-D GPR technique was applied to conduct the full-scale experiment for roadbed cavity detection. The physical experiment has employed the soil characteristics of silty sand soils. The experimental site is composed of physically simulated cavities (Styrofoam, ɛr = 1.03) with dome-shaped structure and concrete sewage conduit. The simulated cavities were installed at regular intervals in spatial distribution. The land surface of the site was not paved with asphalt concrete at the current stage of the experiments. The results of the GPR measurements over the experimental site show that the reflection patterns from the simulated cavities are hyperbolic returns typical to the point source in 2-D perspective. A closer inspection of 3-D GPR volume data has yielded more clear interpretation than 2-D GPR data regarding where the cavities are situated in space. However, in case sewage conduits adjacent to the cavities are present, they could mask the GPR signals from cavities, leading misinterpretations. Therefore, data processing procedures should be more appropriately applied compared to the data for linear target detections. It is strongly believed that 3-D high density GPR data could be usefully applied to the roadbed cavity detections in the experiments. This study is an ongoing project of KIGAM and more realistic environments of the underground conditions would be prepared for the future study.

  9. ROS-based ground stereo vision detection: implementation and experiments.

    PubMed

    Hu, Tianjiang; Zhao, Boxin; Tang, Dengqing; Zhang, Daibing; Kong, Weiwei; Shen, Lincheng

    This article concentrates on open-source implementation on flying object detection in cluttered scenes. It is of significance for ground stereo-aided autonomous landing of unmanned aerial vehicles. The ground stereo vision guidance system is presented with details on system architecture and workflow. The Chan-Vese detection algorithm is further considered and implemented in the robot operating systems (ROS) environment. A data-driven interactive scheme is developed to collect datasets for parameter tuning and performance evaluating. The flying vehicle outdoor experiments capture the stereo sequential images dataset and record the simultaneous data from pan-and-tilt unit, onboard sensors and differential GPS. Experimental results by using the collected dataset validate the effectiveness of the published ROS-based detection algorithm.

  10. Closing supersymmetric resonance regions with direct detection experiments

    SciTech Connect

    Kelso, Chris

    2014-01-01

    One of the few remaining ways that neutralinos could potentially evade constraints from direct detection experiments is if they annihilate through a resonance, as can occur if 2m{sub χ⁰} falls within about ~10% of either m{sub A/H}, m{sub h}, or m{sub Z}. Assuming a future rate of progress among direct detection experiments that is similar to that obtained over the past decade, we project that within 7 years the light Higgs and Z pole regions will be entirely closed, while the remaining parameter space near the A/H resonance will require that 2m{sub χ₀} be matched to the central value (near m{sub A}) to within less than 4%. At this rate of progress, it will be a little over a decade before multi-ton direct detection experiments will be able to close the remaining, highly-tuned, regions of the A/H resonance parameter space.

  11. Radiologists' Training, Experience, and Attitudes About Elder Abuse Detection.

    PubMed

    Rosen, Tony; Bloemen, Elizabeth M; Harpe, Jasmin; Sanchez, Allen M; Mennitt, Kevin W; McCarthy, Thomas J; Nicola, Refky; Murphy, Kieran; LoFaso, Veronica M; Flomenbaum, Neal; Lachs, Mark S

    2016-12-01

    Elder abuse is underrecognized, and identification of subtle cases requires a high index of suspicion among all health care providers. Because many geriatric injury victims undergo radiographic imaging, diagnostic radiologists may be well positioned to identify injury patterns suggestive of abuse. Little is known about radiologists' experience with elder abuse. Our goal was to describe knowledge, attitudes, training, and practice experience in elder abuse detection among diagnostic radiologists. We conducted 19 interviews with diagnostic radiologists at a large urban academic medical center using a semistructured format. Data from these sessions were coded and analyzed to identify themes. Only two radiologists reported any formal or informal training in elder abuse detection. All subjects believed they had missed cases of elder abuse. Even experienced radiologists reported never having received a request from a referring physician to assess images for evidence suggestive of elder abuse. All subjects reported a desire for additional elder abuse training. Also, subjects identified radiographic findings or patterns potentially suggestive of elder abuse, including high-energy injuries such as upper rib fractures, injuries in multiple stages of healing, and injuries inconsistent with reported mechanism. Radiologists are uniquely positioned to identify elder abuse. Though training in detection is currently lacking, providers expressed a desire for increased knowledge. In addition, radiologists were able to identify radiographic findings suggestive of elder abuse. On the basis of these findings, we plan to conduct additional studies to define pathognomonic injury patterns and to explore how to empower radiologists to incorporate detection into their practice.

  12. Development and evaluation of an indirect enzyme-linked immunosorbent assay for the detection of antibodies against Campylobacter fetus in cattle.

    PubMed

    Zhao, Hailing; Liu, Huifang; Du, Yanfen; Liu, Siguo; Ni, Hongbo; Wang, Yong; Wang, Chunlai; Si, Wei; Yang, Jinguo; Ling, Jingkai

    2010-06-01

    Campylobacteriosis is a zoonosis that occurs worldwide. Infection with Campylobacter fetus (C. fetus) causes infertility and abortion in sheep and cattle. The current study focuses on the SapA gene of C. fetus that encodes surface array proteins and plays an important role in the virulence of C. fetus. The SapA-N (1398bp) and SapA-C (1422bp) fragments were amplified from the C. fetusSapA gene using polymerase chain reaction (PCR), and the corresponding recombinant proteins rSapA-N and rSapA-C were expressed in Escherichia. coli BL21 cells. Results of Western blotting and enzyme-linked immunosorbent assay (ELISA) showed that the immunological activity of rSapA-N was higher than that of rSapA-C (P<0.05). Therefore, rSapA-N was selected to establish an indirect ELISA for detecting antibodies against C. fetus. The diagnostic criteria were as follows: S/P0.45: positive; S/P<0.4: negative; 0.45>S/P0.4: suspected. The specificity and sensitivity of our method were 94.3% and 88.6%, respectively. Moreover, no cross-reactions were observed between rSapA-N and serum samples that were positive for other bovine bacterial pathogens diseases such as Mycobacterium avium subspecies paratuberculosis. One hundred and two serum samples from cows that had experienced abortion were tested. Four and 2 C. fetus-positive serum samples were found among the 70 bovine brucellosis-positive samples and the 32 infectious bovine rhinotracheitis (IBR)-positive samples, respectively. The findings suggest that the rSapA-N-based ELISA method has immense potential in future applications. Copyright 2009 Elsevier Ltd. All rights reserved.

  13. Small Arrays for Seismic Intruder Detections: A Simulation Based Experiment

    NASA Astrophysics Data System (ADS)

    Pitarka, A.

    2014-12-01

    Seismic sensors such as geophones and fiber optic have been increasingly recognized as promising technologies for intelligence surveillance, including intruder detection and perimeter defense systems. Geophone arrays have the capability to provide cost effective intruder detection in protecting assets with large perimeters. A seismic intruder detection system uses one or multiple arrays of geophones design to record seismic signals from footsteps and ground vehicles. Using a series of real-time signal processing algorithms the system detects, classify and monitors the intruder's movement. We have carried out numerical experiments to demonstrate the capability of a seismic array to detect moving targets that generate seismic signals. The seismic source is modeled as a vertical force acting on the ground that generates continuous impulsive seismic signals with different predominant frequencies. Frequency-wave number analysis of the synthetic array data was used to demonstrate the array's capability at accurately determining intruder's movement direction. The performance of the array was also analyzed in detecting two or more objects moving at the same time. One of the drawbacks of using a single array system is its inefficiency at detecting seismic signals deflected by large underground objects. We will show simulation results of the effect of an underground concrete block at shielding the seismic signal coming from an intruder. Based on simulations we found that multiple small arrays can greatly improve the system's detection capability in the presence of underground structures. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344

  14. Construction of an AMR magnetometer for car detection experiments

    NASA Astrophysics Data System (ADS)

    Fúra, V.; Petrucha, V.; Platil, A.

    2016-03-01

    A new construction of magnetometer with commercially available AMR (anisotropic magnetoresistive) sensors intended for vehicle detection experiments is presented. Initial experiments with simple AMR gradiometer indicated viability of the approach in a real- world setup. For further experiments and acquisition of representative data, a new design of precise multi-channel magnetometer was developed. The design supports two models of commercial AMR sensors: the proven and reliable, but obsolete Honeywell HMC1021-series sensors and newly available Sensitec AFF755B sensors. In the comparison the two types are similar in most achieved parameters, except offset stability in flipped operation regime. Unfortunately, the new AFF755B sensors seem to have perhaps inferior coupling of the flipping (set/reset) coil to the ferromagnetic core that causes insufficient saturation of the AMR material. The issue is being solved by Sensitec, current deliverables of the AFF755B have “product sample” status (September 2015).

  15. High-resolution 3D CANCA NMR experiments for complete mainchain assignments using C(alpha) direct detection.

    PubMed

    Takeuchi, Koh; Frueh, Dominique P; Hyberts, Sven G; Sun, Zhen-Yu J; Wagner, Gerhard

    2010-03-10

    The primary limitation of solution state NMR with larger, highly dynamic, or paramagnetic systems originates from signal losses due to fast transverse relaxation. This is related to the high gyromagnetic ratio gamma of protons, which are usually detected. Thus, it is attractive to consider detection of nuclei with lower gamma, such as (13)C, for extending the size limits of NMR. Here, we present an approach for complete assignment of C(alpha) and N resonances in fast relaxing proteins using a C(alpha) detected 3D CANCA experiment for perdeuterated proteins. The CANCA experiment correlates alpha carbons with the sequentially adjacent and succeeding nitrogen and alpha carbons. This enables elongation of the chain of assigned residues simply by navigating along both nitrogen and carbon dimensions using a "stairway" assignment procedure. The simultaneous use of both C(alpha) and N sequential connectivities makes the experiment more robust than conventional 3D experiments, which rely solely on a single (13)C indirect dimension for sequential information. The 3D CANCA experiment, which is very useful for mainchain assignments of higher molecular weight proteins at high magnetic field, also provides an attractive alterative for smaller proteins. Two versions of the experiment are described for samples that are (13)C labeled either uniformly or at alternate positions for removing one-bond (13)C-(13)C couplings. To achieve both high resolution and sensitivity, extensive nonuniform sampling was employed. Adding longitudinal relaxation enhancement agents can allow for shorter recycling delays, decreased measuring time, or enhanced sensitivity.

  16. Light dark matter detection prospects at neutrino experiments

    SciTech Connect

    Kumar, Jason; Learned, John G.; Smith, Stefanie

    2009-12-01

    We consider the prospects for the detection of relatively light dark matter through direct annihilation to neutrinos. We specifically focus on the detection possibilities of water Cherenkov and liquid scintillator neutrino detection devices. We find, in particular, that liquid scintillator detectors may potentially provide excellent detection prospects for dark matter in the 4-10 GeV mass range. These experiments can provide excellent corroborative checks of the DAMA/LIBRA annual modulation signal, but may yield results for low mass dark matter in any case. We identify important tests of the ratio of electron to muon neutrino events (and neutrino versus antineutrino events), which discriminate against background atmospheric neutrinos. In addition, the fraction of events which arise from muon neutrinos or antineutrinos (R{sub {mu}} and R{sub {mu}}) can potentially yield information about the branching fractions of hypothetical dark matter annihilations into different neutrino flavors. These results apply to neutrinos from secondary and tertiary decays as well, but will suffer from decreased detectability.

  17. An investigation of signal performance enhancements achieved through innovative pixel design across several generations of indirect detection, active matrix, flat-panel arrays

    SciTech Connect

    Antonuk, Larry E.; Zhao Qihua; El-Mohri, Youcef; Du Hong; Wang Yi; Street, Robert A.; Ho, Jackson; Weisfield, Richard; Yao, William

    2009-07-15

    Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and/or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 {mu}m. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 {mu}m pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of {approx}80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 {mu}m pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or

  18. An investigation of signal performance enhancements achieved through innovative pixel design across several generations of indirect detection, active matrix, flat-panel arrays

    PubMed Central

    Antonuk, Larry E.; Zhao, Qihua; El-Mohri, Youcef; Du, Hong; Wang, Yi; Street, Robert A.; Ho, Jackson; Weisfield, Richard; Yao, William

    2009-01-01

    Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and∕or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 μm. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 μm pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of ∼80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 μm pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or continuous

  19. Direct and indirect effects of biochar on the mobility of metals and nutrients in contaminated soils: a two-column leaching experiment

    NASA Astrophysics Data System (ADS)

    Rees, Frédéric; Simonnot, Marie-Odile; Morel, Jean-Louis

    2014-05-01

    experiment. This observation highlights the slow, diffusive nature of biochar chemical interactions with the soil. The comparison of samples enabled us to quantify the immobilization of elements on biochar from its indirect effect on the retention capacity of the soil, mostly due to the increase of pH and the dynamics of inorganic and organic carbon in the solution. Altogether, these results provide new information about the complex effects of biochar on soil properties and about its efficiency in the context of soil remediation.

  20. SPARTUVIX II: An improved x-ray ultraviolet spectrograph with temporal and spatial capabilities for indirect drive inertial confinement fusion experiments (abstract)

    SciTech Connect

    Bourgade, J.L.; Guilly, E.; Bruneau, J.; Gary, S.; Gontier, D.; Renaudin, P.; Reverdin, C.; Thiell, G.

    1997-01-01

    An improved version of the initial x-ray ultraviolet spectrograph SPARTUVIX1 has been developed to record the time evolution of spatially resolved spectra in the soft x-ray range (from 30 to 300 {Angstrom}). This diagnostic can be applied to the new class of laser produced plasma experiments now performed in order to better understand the physical evolution of x-ray indirect drive plasmas. Instead of a one-dimensional streak camera used for the first version, a new widely used 2-D soft x-ray time gated imager allows us to follow the time evolution of the spatially resolved soft x-ray spectra. This instrument was designed for plastic foam soft x-ray opacity measurements. The soft x-rays, emitted by an auxiliary radiography laser plasma source, are transmitted through the foam and dispersed into two parts (+1 and {minus}1 order of the transmission grating). Each dispersed spectrum is placed on two different gated striplines of the soft x-ray imager and thus recorded at two different times (exposure time 300 ps, adjustable interframe 600 ps). The spatial resolution is obtained with a slit added in front of the spectrograph, that images the plasma onto the detector with a magnification ratio of 15 and a spatial resolution of 50 {mu}m. A detailed description of this instrument and the main results obtained for two different plastic foam opacity measurements (undoped and doped with chlorine) will be presented. This work is supported by European Community Contract No. CEE/CHGF-CT-92-0016. {copyright} {ital 1997 American Institute of Physics.}

  1. Simulation of Seismic Tunnel Detection Experiments in Heterogeneous Geological Media

    NASA Astrophysics Data System (ADS)

    Sherman, C. S.; Glaser, S. D.; Rector, J.

    2013-12-01

    Detecting covert tunnels and other underground openings is an important yet challenging problem for geophysicists, especially where geological heterogeneity is pronounced. A number of geophysical methods have been employed to solve this problem, each with varying degrees of success. We focus on the near-surface seismic techniques of surface wave backscattering, surface wave attenuation tomography, body wave diffraction imaging, and resonant imaging. We use the elastodynamic wave propagation code E3D to simulate tunnel detection experiments completed at this site for a range of synthetic fractal velocity models. The Black Diamond mine, located near Pittsburg California, is used for the field test of our analysis. Our results show that for the relatively low-frequency surface wave attenuation and backscattering methods, the maximum detectable tunnel depth in a homogenous medium is approximately equal to the wavelength of the probing Rayleigh wave. The higher-frequency body wave diffraction and resonant imaging techniques are able to locate tunnels at greater depths, but require more sophisticated analysis and are prone to greater attenuation losses. As is expected, for large values of heterogeneity amplitude, ɛ, the percent standard deviation from the mean velocity model, the average observed surface wave attenuation signal decreases and the maximum detectable tunnel depth decreases. However, for moderate values of heterogeneity amplitude (ɛ < 3%), the average surface wave attenuation signal increases and the maximum detectable tunnel depth increases. For the body wave diffraction and resonant imaging experiments, as ɛ increases the complexity of the observed signal increases, resulting in more difficult processing and interpretation. The additional scattering attenuation tends to degrade the signals significantly due to their reliance on lower amplitude and higher frequency waves.

  2. Data analysis and double pulse detection for the MARE experiment

    NASA Astrophysics Data System (ADS)

    Armstrong, Jonathan D.

    With their existence first proposed in 1930, neutrinos have subsequently proven themselves as experts at avoiding detection. Until early this century, it was not even known if neutrinos were massive particles. With the results of neutrino oscillation experiments such as Super-Kamiokande and SNO, we now know that neutrinos have a non-zero mass. However, these experiments are only sensitive to the difference of the square of neutrino mass eigenstates and do not provide sufficient information to resolve the neutrino mass hierarchy. Several complimentary methods are being explored to obtain an absolute mass scale, but the most promising model-independent approach is high precision spectroscopy of the beta-spectrum endpoint (Q-value). In general, all energy from the decay is detected except for that of the neutrino, which results in a correction near the endpoint of the spectrum that is related to the neutrino rest mass. To detect this difference requires excellent energy resolution. This may be obtained by utilizing a scalable approach consisting of microcalorimeter arrays with the beta-decay source embedded in the absorber. Two such experiments, Troitsk and Mainz have been able to set an upper limit of 2.3 eV on the neutrino mass, but higher precision is needed. MARE (Microcalorimeter Arrays for a Rhenium Experiment) is the successor to these experiments and plans to obtain resolution in the sub-eV range. Using an analysis program developed at the University of Miami, we have been able to verify the creation of holmium-163 which has a higher activity than rehenium-187. A landmark in the MARE project, this higher activity can provide better statistics and reduces the live time and array size requirements for a given sensitivity. One of the primary limits on the sensitivity of the MARE project, related to the source activity, is the pile-up spectrum, which is the result of unresolved double pulses. We have developed a platform to explore the efficiency of different

  3. Monthly modulation in dark matter direct-detection experiments

    SciTech Connect

    Britto, Vivian; Meyers, Joel E-mail: jmeyers@cita.utoronto.ca

    2015-11-01

    The signals in dark matter direct-detection experiments should exhibit modulation signatures due to the Earth's motion with respect to the Galactic dark matter halo. The annual and daily modulations, due to the Earth's revolution about the Sun and rotation about its own axis, have been explored previously. Monthly modulation is another such feature present in direct detection signals, and provides a nearly model-independent method of distinguishing dark matter signal events from background. We study here monthly modulations in detail for both WIMP and WISP dark matter searches, examining both the effect of the motion of the Earth about the Earth-Moon barycenter and the gravitational focusing due to the Moon. For WIMP searches, we calculate the monthly modulation of the count rate and show the effects are too small to be observed in the foreseeable future. For WISP dark matter experiments, we show that the photons generated by WISP to photon conversion have frequencies which undergo a monthly modulating shift which is detectable with current technology and which cannot in general be neglected in high resolution WISP searches.

  4. GPR Experiments of the Simulated Cavity Detection in Urban Areas

    NASA Astrophysics Data System (ADS)

    Kim, Changryol; Kang, Woong; Son, Jeongsul; Jeong, Soocheol

    2017-04-01

    Recent years, the deteriorated underground facilities such as sewage or water supply pipes have increased significantly with growing urban development in Korea. The soils surrounding old damaged pipes were washed away beneath the roadbed, causing underground cavities and eventual ground cave-ins in the urban areas. The detection of the roadbed cavities is, therefore, required to prevent property damage and loss of human lives for precautionary measures. In general, GPR is well known as a suitable geophysical technique for shallow underground cavity detection. 3-D GPR technique was applied to conduct the full-scale experiment for roadbed cavity detection. The physical experiment has employed the testing ground with soil characteristics of silty sand soils. The experimental test ground consists of physically simulated cavities with dome-shaped structure, and of hume concrete and cast-iron pipes to simulate underground facilities. The pipes were installed more than one meter below the land surface and simulated cavities nearby were also installed at regular intervals in spatial distribution. The land surface of the site was not paved with asphalt concrete at the current stage of the experiments. The GPR data was obtained to investigate GPR responses due to different antenna orientations (HH and VV antenna orientations) over the testing ground. The results of the experiment show that the reflection patterns from the simulated cavities are hyperbolic returns typical to the point source in 2-D perspective. The different antenna orientations have shown the different areal extents of the hyperbolic reflections patterns from the cavities, and have shown the different characteristics over the pipes on the data. A closer inspection of 3-D GPR volume data has yielded more clear interpretation than 2-D GPR data regarding where the cavities are situated and what kind of shape the cavities show in space. This study is an ongoing project of KIGAM at a second stage of the physical

  5. Results of the radio-detection experiment CODALEMA

    NASA Astrophysics Data System (ADS)

    Lautridou, P.; CODALEMA Collaboration

    2009-06-01

    Measurements of the radio transients associated with Extensive Air Showers could provide a timely new effective method of detection of Ultra-High-Energy Cosmic Rays with interesting performances in terms of techniques and of accessible observables. The CODALEMA experiment at the Radio Observatory of Nançay, France, explores this possibility using an array of broadband active dipole antennas triggered by an array of ground particle detectors. The implemented detection techniques, the methods of analysis developed and the principal results achieved during the 5 years of upgrading will be recalled. This cursory glance will provide an opportunity to point out some new issues and to suggest some future challenges in this domain.

  6. Glacial Till Detection Experiments With Transient Electromagnetic Methods

    NASA Astrophysics Data System (ADS)

    Bucki, A. K.; Adema, G.

    2003-12-01

    Transient Electromagnetic (TEM) investigations have been carried out on Fireweed Rock Glacier in Wrangell-St. Elias National Park, Alaska and the East Fork Toklat Glacier in Denali National Park, Alaska. TEM methods were effective in determining the geometry of the rock glacier but were more limited in resolution on the ice glacier. A conductive layer beneath the rock glacier was identified, and its distribution is consistent with a till-like layer. A similar layer was not detected beneath the glacier; the lack of this conductive layer limits the resolution of glacial depth. These experiments and forward modeling indicate that TEM methods may provide a means for detecting a sufficiently thick and conductive till layer beneath glaciers and rock glaciers.

  7. Experiment to Detect Accelerating Modes in a Photonic Bandgap Fiber

    SciTech Connect

    England, R.J.; Colby, E.R.; Ischebeck, R.; McGuinness, C.M.; Noble, R.; Plettner, T.; Sears, C.M.S.; Siemann, R.H.; Spencer, J.E.; Walz, D.; /SLAC

    2011-11-21

    An experimental effort is currently underway at the E-163 test beamline at Stanford Linear Accelerator Center to use a hollow-core photonic bandgap (PBG) fiber as a high-gradient laser-based accelerating structure for electron bunches. For the initial stage of this experiment, a 50pC, 60 MeV electron beam will be coupled into the fiber core and the excited modes will be detected using a spectrograph to resolve their frequency signatures in the wakefield radiation generated by the beam. They will describe the experimental plan and recent simulation studies of candidate fibers.

  8. Experiment to Detect Accelerating Modes in a Photonic Bandgap Fiber

    SciTech Connect

    England, R. J.; Colby, E. R.; McGuinness, C. M.; Noble, R.; Plettner, T.; Siemann, R. H.; Spencer, J. E.; Walz, D.; Ischebeck, R.; Sears, C. M. S.

    2009-01-22

    An experimental effort is currently underway at the E-163 test beamline at Stanford Linear Accelerator Center to use a hollow-core photonic bandgap (PBG) fiber as a high-gradient laser-based accelerating structure for electron bunches. For the initial stage of this experiment, a 50 pC, 60 MeV electron beam will be coupled into the fiber core and the excited modes will be detected using a spectrograph to resolve their frequency signatures in the wakefield radiation generated by the beam. We will describe the experimental plan and recent simulation studies of candidate fibers.

  9. Fabrication experiments on supersmooth optics for extrasolar planet detection

    NASA Technical Reports Server (NTRS)

    Ftaclas, C.; Krim, M. H.; Terrile, R. J.

    1989-01-01

    The direct detection of extrasolar planets by imaging will require reductions in scattered and diffracted light by factors in excess of 1000 within one arcsecond of a bright source. While diffraction can be reduced by a number of approaches, small angle scatter can only be reduced by controlling midspatial frequency figure errors. The surface requirements are reviewed and their meaning when compared to the data base of existing mirrors is considered. Experiments are discribed that were successful in reducing midspatial frequency figure so that the scatter level was 500 times less than diffraction for a 25-cm spherical mirror.

  10. Photon Detection System Designs for the Deep Underground Neutrino Experiment

    SciTech Connect

    Whittington, Denver

    2015-11-19

    The Deep Underground Neutrino Experiment (DUNE) will be a premier facility for exploring long-standing questions about the boundaries of the standard model. Acting in concert with the liquid argon time projection chambers underpinning the far detector design, the DUNE photon detection system will capture ultraviolet scintillation light in order to provide valuable timing information for event reconstruction. To maximize the active area while maintaining a small photocathode coverage, the experiment will utilize a design based on plastic light guides coated with a wavelength-shifting compound, along with silicon photomultipliers, to collect and record scintillation light from liquid argon. This report presents recent preliminary performance measurements of this baseline design and several alternative designs which promise significant improvements in sensitivity to low-energy interactions.

  11. Photon detection system designs for the Deep Underground Neutrino Experiment

    NASA Astrophysics Data System (ADS)

    Whittington, D.

    2016-05-01

    The Deep Underground Neutrino Experiment (DUNE) will be a premier facility for exploring long-standing questions about the boundaries of the standard model. Acting in concert with the liquid argon time projection chambers underpinning the far detector design, the DUNE photon detection system will capture ultraviolet scintillation light in order to provide valuable timing information for event reconstruction. To maximize the active area while maintaining a small photocathode coverage, the experiment will utilize a design based on plastic light guides coated with a wavelength-shifting compound, along with silicon photomultipliers, to collect and record scintillation light from liquid argon. This report presents recent preliminary performance measurements of this baseline design and several alternative designs which promise significant improvements in sensitivity to low-energy interactions.

  12. Detectability of strange matter in heavy ion experiments

    SciTech Connect

    Schaffner, J., ||; Diener, A.; Stocker, H.,; Greiner, C.,

    1997-06-01

    We discuss the properties of two distinct forms of hypothetical strange matter, small lumps of strange quark matter (strangelets) and of hyperon matter [metastable exotic multihypernuclear objects (MEMO{close_quote}s)], with special emphasis on their relevance for present and future heavy ion experiments. The masses of small strangelets up to A{sub B}=40 are calculated using the MIT bag model with shell mode filling for various bag parameters. The strangelets are checked for possible strong and weak hadronic decays, also taking into account multiple hadron decays. It is found that strangelets which are stable against strong decay are most likely highly negatively charged, contrary to previous findings. Strangelets can be stable against weak hadronic decay but their masses and charges are still rather high. This has serious impact on the present high sensitivity searches in heavy ion experiments at the AGS and CERN facilities. On the other hand, highly charged MEMO{close_quote}s are predicted on the basis of an extended relativistic mean-field model. Those objects could be detected in future experiments searching for short-lived, rare composites. It is demonstrated that future experiments can be sensitive to a much wider variety of strangelets. {copyright} {ital 1997} {ital The American Physical Society}

  13. MSSM A-funnel and the galactic center excess: prospects for the LHC and direct detection experiments

    DOE PAGES

    Freese, Katherine; López, Alejandro; Shah, Nausheen R.; ...

    2016-04-11

    The pseudoscalar resonance or “A-funnel” in the Minimal Supersymmetric Standard Model (MSSM) is a widely studied framework for explaining dark matter that can yield interesting indirect detection and collider signals. The well-known Galactic Center excess (GCE) at GeV energies in the gamma ray spectrum, consistent with annihilation of a ≲ 40 GeV dark matter particle, has more recently been shown to be compatible with significantly heavier masses following reanalysis of the background.For this study, we explore the LHC and direct detection implications of interpreting the GCE in this extended mass window within the MSSM A-funnel framework. We find that compatibilitymore » with relic density, signal strength, collider constraints, and Higgs data can be simultaneously achieved with appropriate parameter choices. The compatible regions give very sharp predictions of 200-600 GeV CP-odd/even Higgs bosons at low tan β at the LHC and spin-independent cross sections ≈ 10-11 pb at direct detection experiments. Finally, regardless of consistency with the GCE, this study serves as a useful template of the strong correlations between indirect, direct, and LHC signatures of the MSSM A-funnel region.« less

  14. MSSM A-funnel and the galactic center excess: prospects for the LHC and direct detection experiments

    SciTech Connect

    Freese, Katherine; López, Alejandro; Shah, Nausheen R.; Shakya, Bibhushan

    2016-04-11

    The pseudoscalar resonance or “A-funnel” in the Minimal Supersymmetric Standard Model (MSSM) is a widely studied framework for explaining dark matter that can yield interesting indirect detection and collider signals. The well-known Galactic Center excess (GCE) at GeV energies in the gamma ray spectrum, consistent with annihilation of a ≲ 40 GeV dark matter particle, has more recently been shown to be compatible with significantly heavier masses following reanalysis of the background.For this study, we explore the LHC and direct detection implications of interpreting the GCE in this extended mass window within the MSSM A-funnel framework. We find that compatibility with relic density, signal strength, collider constraints, and Higgs data can be simultaneously achieved with appropriate parameter choices. The compatible regions give very sharp predictions of 200-600 GeV CP-odd/even Higgs bosons at low tan β at the LHC and spin-independent cross sections ≈ 10-11 pb at direct detection experiments. Finally, regardless of consistency with the GCE, this study serves as a useful template of the strong correlations between indirect, direct, and LHC signatures of the MSSM A-funnel region.

  15. Older Adults' Experience with a Novel Fall Detection Device.

    PubMed

    Demiris, George; Chaudhuri, Shomir; Thompson, Hilaire J

    2016-09-01

    Falls are a significant concern for the older adult (OA) population, many of whom are unable to get up following a fall. While many devices exist designed to detect a fall, little work has been conducted to evaluate the usability of such devices. We present a longitudinal usability study of a fall detection (FD) device tested with OAs in real-world settings. OAs were recruited and asked to use a wearable FD device for up to 4 months. Participants were interviewed at baseline and 2 and 4 months and encouraged to provide direct feedback on their experience. In total, 18 OAs participated in the study. Eight completed the 4-month trial. We conducted a total of 38 interviews (16 baseline, 7 midpoint, and 15 final) and logged a total of 78 comments. While participants enjoyed the GPS and automatic detection features of the device, they were unhappy with the volume of false alarms and obtrusiveness of the device. Many also did not see a great need for having the device or were embarrassed by the device. Engineers must work to better develop this technology so that it is accessible to people with hearing loss, limited dexterity, and low vision. Utilizing age-appropriate design techniques will help make such informatics tools more user friendly. We explored the usability of a particular FD device with OAs and provide design recommendations to help future device manufacturers create more age-appropriate devices.

  16. Older Adults' Experience with a Novel Fall Detection Device

    PubMed Central

    Chaudhuri, Shomir; Thompson, Hilaire J.

    2016-01-01

    Abstract Background: Falls are a significant concern for the older adult (OA) population, many of whom are unable to get up following a fall. Introduction: While many devices exist designed to detect a fall, little work has been conducted to evaluate the usability of such devices. We present a longitudinal usability study of a fall detection (FD) device tested with OAs in real-world settings. Materials and Methods: OAs were recruited and asked to use a wearable FD device for up to 4 months. Participants were interviewed at baseline and 2 and 4 months and encouraged to provide direct feedback on their experience. Results: In total, 18 OAs participated in the study. Eight completed the 4-month trial. We conducted a total of 38 interviews (16 baseline, 7 midpoint, and 15 final) and logged a total of 78 comments. While participants enjoyed the GPS and automatic detection features of the device, they were unhappy with the volume of false alarms and obtrusiveness of the device. Many also did not see a great need for having the device or were embarrassed by the device. Discussion: Engineers must work to better develop this technology so that it is accessible to people with hearing loss, limited dexterity, and low vision. Utilizing age-appropriate design techniques will help make such informatics tools more user friendly. Conclusion: We explored the usability of a particular FD device with OAs and provide design recommendations to help future device manufacturers create more age-appropriate devices. PMID:26959299

  17. Direct and Indirect Educational Relationships: Developing a Typology for the Contribution of Different Categories of School Staff in Relation to Students' Educational Experiences

    ERIC Educational Resources Information Center

    Frelin, Anneli; Grannäs, Jan

    2015-01-01

    This article presents results from a research project exploring the relational interplay between school staff and students, its functions and complexity in the secondary school context. School relationships (between students and different kinds of staff) are more or less indirectly related to educational content: subject matter as well as norms…

  18. Direct and Indirect Educational Relationships: Developing a Typology for the Contribution of Different Categories of School Staff in Relation to Students' Educational Experiences

    ERIC Educational Resources Information Center

    Frelin, Anneli; Grannäs, Jan

    2015-01-01

    This article presents results from a research project exploring the relational interplay between school staff and students, its functions and complexity in the secondary school context. School relationships (between students and different kinds of staff) are more or less indirectly related to educational content: subject matter as well as norms…

  19. Indirection and computer security.

    SciTech Connect

    Berg, Michael J.

    2011-09-01

    The discipline of computer science is built on indirection. David Wheeler famously said, 'All problems in computer science can be solved by another layer of indirection. But that usually will create another problem'. We propose that every computer security vulnerability is yet another problem created by the indirections in system designs and that focusing on the indirections involved is a better way to design, evaluate, and compare security solutions. We are not proposing that indirection be avoided when solving problems, but that understanding the relationships between indirections and vulnerabilities is key to securing computer systems. Using this perspective, we analyze common vulnerabilities that plague our computer systems, consider the effectiveness of currently available security solutions, and propose several new security solutions.

  20. GPR for detecting buried animal bones in controlled sandbox experiments

    NASA Astrophysics Data System (ADS)

    Schneider, B.; Tsoflias, G. P.

    2016-12-01

    Bone-beds can provide a wealth of information at archeological sites, including age of the site, site formation processes, seasonality of the kill, size and gender of the herd, and paleoenvironmental conditions at the time of the kill. Ground-penetrating radar (GPR) is a non-invasive, cost-effective technique that has the potential to delineate the horizontal and vertical limits of bone-beds in different geomorphological settings. Furthermore, the identification of a bone signature from geophysical methods can have modern day applications, particularly in forensic research investigations. There have been previous attempts, mostly in forensic studies and studies that involve mapping graveyards, to locate buried bone using geophysics. Although geophysical tools have successfully identified buried remains of homicide victims and the location of graves, these finds resulted from the identification of anomalies related to the disturbed soil in graves and not to an anomalous signal from the bone itself. It is necessary to detect the signal from the bone at these archaeological sites, because prehistoric animal remains typically were not buried immediately upon death, but instead became covered over time by sediment. Initial lab experiments determined the electrical properties (i.e. the relative permittivity, loss factor, and loss tangent values) of modern animal bone and indicate that bone is a desirable low-loss target for GPR detection. In order to test these results, we have built a 1x2x1 meter sandbox and placed modern bison bone inside of it to simulate natural burial conditions. This research presents successful GPR detection of the vertical and horizontal extents of the buried bison bone. In addition, changes in variables such as depth of burial, size and shape of target, and antenna orientation are presented to assess the overall detection capability of GPR for this unique archaeological feature.

  1. Indirect techniques in nuclear astrophysics: a review.

    PubMed

    Tribble, R E; Bertulani, C A; Cognata, M La; Mukhamedzhanov, A M; Spitaleri, C

    2014-10-01

    In this review, we discuss the present status of three indirect techniques that are used to determine reaction rates for stellar burning processes, asymptotic normalization coefficients, the Trojan Horse method and Coulomb dissociation. A comprehensive review of the theory behind each of these techniques is presented. This is followed by an overview of the experiments that have been carried out using these indirect approaches.

  2. High-performance anion-exchange chromatography coupled with pulsed amperometric detection and capillary zone electrophoresis with indirect ultra violet detection as powerful tools to evaluate prebiotic properties of fructooligosaccharides and inulin.

    PubMed

    Corradini, C; Bianchi, F; Matteuzzi, D; Amoretti, A; Rossi, M; Zanoni, S

    2004-10-29

    Fructooligosaccharides (FOS) and inulin are food grade non-digestible carbohydrates that exert beneficial nutritional effect. This paper describes the suitability of high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) and capillary zone electrophoresis (CZE) to evaluate fermentation properties of FOS and inulin in pure Bifidobacterium cultures; and to study their effects on faecal cultures (microbial population and short-chain fatty acids). Prebiotic effectiveness of FOS and inulin of different degrees of polymerization was evaluated monitoring the changes in their molecular weight distribution during the in vitro growth of selected Bifidobacterium strains. The qualitative analysis of the residual soluble oligosaccharides or polysaccharides from Raftilose Synergy, Raftiline HP and Raftilose P95 was carried out by HPAEC-PAD, using a CarboPac PA 100 column and an appositely optimized gradient elution program. Under the optimized gradient elution conditions, glucose, fructose, sucrose were resolved from each other and from fructans with a DP ranging from 3 (1-kestose) to 60. The chromatographic profiles of the spent broths pointed out that almost every strain presented a different capability to ferment fructan chains of variable DP, indicating wide strain to strain differences. To explore the prebiotic effect of FOS and inulin, related to of short chain fatty acids (SCFAs) accumulation in faecal cultures due to fermentative metabolism of intestinal microflora, analysis of SCFAs, acetic and lactic acid was achieved by co-electroosmotic capillary electrophoresis, where the electrophoretic mobility of the anionic analytes and electroosmotic flow (EOF) were similarly directed. Moreover, the use of UV detection for the analyses of our organic anions required a running electrolyte which allowed indirect detection. The optimization of the capillary electrophoretic conditions was carried out by applying a chemometric study

  3. Validation of an indirect enzyme-linked immunosorbent assay for the detection of antibody against Brucella abortus in cattle sera using an automated ELISA workstation.

    PubMed

    Paweska, J T; Potts, A D; Harris, H J; Smith, S J; Viljoen, G J; Dungu, B; Brett, O L; Bubb, M; Prozesky, L

    2002-03-01

    An automated indirect enzyme-linked immunosorbent assay (I-ELISA) for the serological diagnosis of bovine brucellosis was developed and validated in-house. A total of 4,803 cattle sera from South Africa (n = 3,643), Canada (n = 652), Germany (n = 240), France (n = 73) and the USA (n = 195) was used. The South African panel of sera represented 834 sera known to be positive by the Rose Bengal test (RBT), serum agglutination test (SAT) and complement fixation test (CFT), 2709 sera that were negative by CFT, and 100 sera from animals vaccinated with a standard dose of Brucella abortus strain 19. Overseas sera were obtained from reference non-vaccinated brucella-free cattle (n = 834), naturally infected (n = 72), experimentally infected (n = 71), and vaccinated animals (n = 83). Also 100 sera collected from cattle in Canada and known to be positive by competitive ELISA (C-ELISA) were used. The intermediate ranges ("borderline" range for the interpretation of test results) were derived from two-graph receiver operating characteristics analysis. The lowest values of the misclassification cost-term analysis obtained from testing overseas panels, covered lower I-ELISA cut-off PP values (0.02-3.0) than those from local panels (1.5-5.0). The relatively low cut-off PP values selected for I-ELISA were due to the fact that the positive control used represents a very strong standard compared to other reference positive sera. The greater overlap found between negative and positive cattle sera from South Africa than that between reference overseas panels was probably due to the different criteria used in classifying these panels as negative (sera from true non-diseased/non-infected animals) or positive (sera from true diseased/infected animals). The diagnostic sensitivity of the I-ELISA (at the optimum cut-off value) was 100% and of the CFT 83.3%. The diagnostic specificity of I-ELISA was 99.8% and of the CFT 100%. Estimate of Youden's index was higher for the I-ELISA (0.998) than

  4. Atomic detection in microwave cavity experiments: A dynamical model

    SciTech Connect

    Rossi, R. Jr.; Nemes, M. C.; Peixoto de Faria, J. G.

    2007-06-15

    We construct a model for the atomic detection in the context of cavity quantum electrodynamics (QED) used to study coherence properties of superpositions of states of an electromagnetic mode. Analytic expressions for the atomic ionization are obtained, considering the imperfections of the measurement process due to the probabilistic nature of the interactions between the ionization field and the atoms. We provide for a dynamical content for the available expressions for the counting rates considering limited efficiency of detectors. Moreover, we include false countings. The influence of these imperfections on the information about the state of the cavity mode is obtained. In order to test the adequacy of our approach, we investigate a recent experiment reported by Maitre [X. Maitre et al., Phys. Rev. Lett. 79, 769 (1997)] and we obtain excellent agreement with the experimental results.

  5. Validation and use of an indirect enzyme-linked immunosorbent assay for detection of antibodies to West Nile virus in American Alligators (Alligator mississippiensis) in Florida.

    PubMed

    Jacobson, Elliott R; Johnson, April J; Hernandez, Jorge A; Tucker, Sylvia J; Dupuis, Alan P; Stevens, Robert; Carbonneau, Dwayne; Stark, Lillian

    2005-01-01

    In October 2002, West Nile virus (WNV) was identified in farmed American alligators (Alligator mississippiensis) in Florida showing clinical signs and having microscopic lesions indicative of central nervous system disease. To perform seroepidemiologic studies, an indirect enzyme-linked immunosorbent assay (ELISA) was developed to determine exposure of captive and wild alligators to WNV. To validate the test, a group of WNV-seropositive and -seronegative alligators were identified at the affected farm using hemagglutination inhibition (HAI) and the plaque reduction neutralization test (PRNT). The indirect ELISA utilized a rabbit anti-alligator immunoglobulins polyclonal antibody as the secondary antibody, and inactivated WNV-infected Vero cells were used as the coating antigen. For all samples (n=58), the results of the ELISA were consistent with the HAI and PRNT findings. Plasma was collected from 669 free-ranging alligators from 21 sites across Florida in April and October 2003. Four samples collected in April and six in October were positive for WNV antibodies using HAI, PRNT, and the indirect ELISA. This indicated that wild alligators in Florida have been exposed to WNV. These findings can be used as a baseline for future surveys.

  6. Chemical Detection and Identification Techniques for Exobiology Flight Experiments

    NASA Technical Reports Server (NTRS)

    Kojiro, Daniel R.; Sheverev, Valery A.; Khromov, Nikolai A.

    2002-01-01

    Exobiology flight experiments require highly sensitive instrumentation for in situ analysis of the volatile chemical species that occur in the atmospheres and surfaces of various bodies within the solar system. The complex mixtures encountered place a heavy burden on the analytical Instrumentation to detect and identify all species present. The minimal resources available onboard for such missions mandate that the instruments provide maximum analytical capabilities with minimal requirements of volume, weight and consumables. Advances in technology may be achieved by increasing the amount of information acquired by a given technique with greater analytical capabilities and miniaturization of proven terrestrial technology. We describe here methods to develop analytical instruments for the detection and identification of a wide range of chemical species using Gas Chromatography. These efforts to expand the analytical capabilities of GC technology are focused on the development of detectors for the GC which provide sample identification independent of the GC retention time data. A novel new approach employs Penning Ionization Electron Spectroscopy (PIES).

  7. Zirconia coated stir bar sorptive extraction combined with large volume sample stacking capillary electrophoresis-indirect ultraviolet detection for the determination of chemical warfare agent degradation products in water samples.

    PubMed

    Li, Pingjing; Hu, Bin; Li, Xiaoyong

    2012-07-20

    In this study, a sensitive, selective and reliable analytical method by combining zirconia (ZrO₂) coated stir bar sorptive extraction (SBSE) with large volume sample stacking capillary electrophoresis-indirect ultraviolet (LVSS-CE/indirect UV) was developed for the direct analysis of chemical warfare agent degradation products of alkyl alkylphosphonic acids (AAPAs) (including ethyl methylphosphonic acid (EMPA) and pinacolyl methylphosphonate (PMPA)) and methylphosphonic acid (MPA) in environmental waters. ZrO₂ coated stir bar was prepared by adhering nanometer-sized ZrO₂ particles onto the surface of stir bar with commercial PDMS sol as adhesion agent. Due to the high affinity of ZrO₂ to the electronegative phosphonate group, ZrO₂ coated stir bars could selectively extract the strongly polar AAPAs and MPA. After systematically optimizing the extraction conditions of ZrO₂-SBSE, the analytical performance of ZrO₂-SBSE-CE/indirect UV and ZrO₂-SBSE-LVSS-CE/indirect UV was assessed. The limits of detection (LODs, at a signal-to-noise ratio of 3) obtained by ZrO₂-SBSE-CE/indirect UV were 13.4-15.9 μg/L for PMPA, EMPA and MPA. The relative standard deviations (RSDs, n=7, c=200 μg/L) of the corrected peak area for the target analytes were in the range of 6.4-8.8%. Enhancement factors (EFs) in terms of LODs were found to be from 112- to 145-fold. By combining ZrO₂ coating SBSE with LVSS as a dual preconcentration strategy, the EFs were magnified up to 1583-fold, and the LODs of ZrO₂-SBSE-LVSS-CE/indirect UV were 1.4, 1.2 and 3.1 μg/L for PMPA, EMPA, and MPA, respectively. The RSDs (n=7, c=20 μg/L) were found to be in the range of 9.0-11.8%. The developed ZrO₂-SBSE-LVSS-CE/indirect UV method has been successfully applied to the analysis of PMPA, EMPA, and MPA in different environmental water samples, and the recoveries for the spiked water samples were found to be in the range of 93.8-105.3%.

  8. COSMIC ANALOGS OF THE STERN-GERLACH EXPERIMENT AND THE DETECTION OF LIGHT BOSONS

    SciTech Connect

    Chelouche, Doron; Guendelman, Eduardo I. E-mail: guendel@bgu.ac.il

    2009-07-01

    We show that, by studying the arrival times of radio pulses from highly magnetized pulsars, it may be possible to detect light spin-0 bosons (such as axions and axion-like particles) with a much greater sensitivity, over a broad particle mass range than is currently reachable by terrestrial experiments and indirect astrophysical bounds. In particular, we study the effect of splitting of photon-boson beams under intense magnetic field gradients in magnetars and show that radio pulses (at meter wavelengths) may be split and shift by a discernible phase down to a photon-boson coupling constant of g {approx} 10{sup -14} GeV{sup -1}; i.e., about 4 orders of magnitude lower than current upper limits on g. The effect increases linearly with photon wavelength with split pulses having equal fluxes and similar polarizations. These properties make the identification of beam-splitting and beam deflection effects straightforward with currently available data. Better understanding of radio emission from magnetars is, however, required to confidently exclude regions in the parameter space when such effects are not observed.

  9. Detecting Tsunami Source Energy and Scales from GNSS & Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Song, Y. T.; Yim, S. C.; Mohtat, A.

    2016-12-01

    Historically, tsunami warnings based on the earthquake magnitude have not been very accurate. According to the 2006 U.S. Government Accountability Office report, an unacceptable 75% false alarm rate has prevailed in the Pacific Ocean (GAO-06-519). One of the main reasons for those inaccurate warnings is that an earthquake's magnitude is not the scale or power of the resulting tsunami. For the last 10 years, we have been developing both theories and algorithms to detect tsunami source energy and scales, instead of earthquake magnitudes per se, directly from real-time Global Navigation Satellite System (GNSS) stations along coastlines for early warnings [Song 2007; Song et al., 2008; Song et al., 2012; Xu and Song 2013; Titov et al, 2016]. Here we will report recent progress on two fronts: 1) Examples of using GNSS in detecting the tsunami energy scales for the 2004 Sumatra M9.1 earthquake, the 2005 Nias M8.7 earthquake, the 2010 M8.8 Chilean earthquake, the 2011 M9.0 Tohoku-Oki earthquake, and the 2015 M8.3 Illapel earthquake. 2) New results from recent state-of-the-art wave-maker experiments and comparisons with GNSS data will also be presented. Related reference: Titov, V., Y. T. Song, L. Tang, E. N. Bernard, Y. Bar-Sever, and Y. Wei (2016), Consistent estimates of tsunami energy show promise for improved early warning, Pur Appl. Geophs., DOI: 10.1007/s00024-016-1312-1. Xu, Z. and Y. T. Song (2013), Combining the all-source Green's functions and the GPS-derived source for fast tsunami prediction - illustrated by the March 2011 Japan tsunami, J. Atmos. Oceanic Tech., jtechD1200201. Song, Y. T., I. Fukumori, C. K. Shum, and Y. Yi (2012), Merging tsunamis of the 2011 Tohoku-Oki earthquake detected over the open ocean, Geophys. Res. Lett., doi:10.1029/2011GL050767. Song, Y. T., L.-L. Fu, V. Zlotnicki, C. Ji, V. Hjorleifsdottir, C.K. Shum, and Y. Yi, 2008: The role of horizontal impulses of the faulting continental slope in generating the 26 December 2004 Tsunami (2007

  10. Indirect immunofluorescent antibody test in chicken leucocytozoonosis.

    PubMed

    Isobe, T; Akiba, K

    1982-01-01

    The indirect immunofluorescent antibody technique was applied to detection of antigens of different developmental stages of Leucocytozoon caulleryi and antibodies in the sera of chickens infected with L. caulleryi by using second generation merozoite and gametocyte antigens. Zygotes, ookinetes and sporozoites in midges, and second generation merozoites and gametocytes in chickens indicated specific fluorescence. Indirect immunofluorescent antibody titers were higher than agar gel precipitation antibody titers. So the detection of the antibody by the indirect immunofluorescent antibody technique was possible in the sera in which the antibody could not be detected by the agal gel precipitation test. Therefore, the indirect immunofluorescent antibody technique was applicable to chicken leucocytozoonosis as a highly sensitive serological diagnostic method.

  11. Development of a sensitive and specific indirect enzyme-linked immunosorbent assay based on a baculovirus recombinant antigen for detection of specific antibodies against Ehrlichia canis.

    PubMed

    López, Lissett; Venteo, Angel; Aguirre, Enara; García, Marga; Rodríguez, Majosé; Amusátegui, Inmaculada; Tesouro, Miguel A; Vela, Carmen; Sainz, Angel; Rueda, Paloma

    2007-11-01

    An indirect enzyme-linked immunosorbent assay (ELISA) based on baculovirus recombinant P30 protein of Ehrlichia canis and the 1BH4 anticanine IgG monoclonal antibody was developed and evaluated by examining a panel of 98 positive and 157 negative sera using the indirect fluorescent antibody (IFA) test as the reference technique. The P30-based ELISA appeared to be sensitive and specific (77.55% and 95.54%, respectively) when qualitative results (positive/negative) were compared with those of the IFA test; the coefficient of correlation (R) between the 2 tests was 0.833. Furthermore, it was possible to establish a mathematical formula for use in comparing the results of both techniques. These results indicate that recombinant P30 antigen-based ELISA is a suitable alternative of the IFA test for simple, consistent, and rapid serodiagnosis of canine ehrlichiosis. Moreover, the use of this recombinant protein as antigen offers a great advantage for antigen preparation in comparison with other techniques in which the whole E. canis organism is used as antigen.

  12. High-resolution 3D CANCA NMR experiments for complete mainchain assignments using Cα direct-detection

    PubMed Central

    Takeuchi, Koh; Frueh, Dominique P.; Hyberts, Sven G.; Sun, Zhen-Yu J.; Wagner, Gerhard

    2010-01-01

    The primary limitation of solution state NMR with larger, highly dynamic, or paramagnetic systems originates from signal losses due to fast transverse relaxation. This is related to the high gyromagnetic ratio γ of protons, which are usually detected. Thus, it is attractive to consider detection of nuclei with lower γ, such as 13C, for extending the size limits of NMR. Here, we present an approach for complete assignment of Cα and N resonances in fast relaxing proteins using a Cα detected 3D CANCA experiment for perdeuterated proteins. The CANCA experiment correlates alpha carbons with the sequentially adjacent and succeeding nitrogen and alpha carbons. This enables elongation of the chain of assigned residues simply by navigating along both nitrogen and carbon dimensions using a “stairway” assignment procedure. The simultaneous use of both Cα and N sequential connectivities makes the experiment more robust than conventional 3D experiments, which rely solely on a single 13C indirect dimension for sequential information. The 3D CANCA experiment, which is very useful for mainchain assignments of higher molecular weight proteins at high magnetic field, also provides an attractive alterative for smaller proteins. Two versions of the experiment are described for samples that are 13C labeled either uniformly or at alternate positions for removing one-bond 13C-13C couplings. In order to achieve both, high resolution and sensitivity, extensive non-uniform sampling was employed. Adding longitudinal relaxation enhancement agents can allow for shorter recycling delays, decreased measuring time, or enhanced sensitivity. PMID:20155902

  13. Indirect Enzyme-Linked Immunosorbent Assay for Detection of Immunoglobulin G Reactive with a Recombinant Protein Expressed from the Gene Encoding the 116-Kilodalton Protein of Mycoplasma pneumoniae

    PubMed Central

    Duffy, Michael F.; Whithear, Kevin G.; Noormohammadi, Amir H.; Markham, Philip F.; Catton, Michael; Leydon, Jennie; Browning, Glenn F.

    1999-01-01

    Serology remains the method of choice for laboratory diagnosis of Mycoplasma pneumoniae infection. Currently available serological tests employ complex cellular fractions of M. pneumoniae as antigen. To improve the specificity of M. pneumoniae diagnosis, a recombinant protein was assessed as a serodiagnostic reagent. A panel of recombinant proteins were expressed from a cloned M. pneumoniae gene that encodes a 116-kDa surface protein antigen. The recombinant proteins were assessed for reactivity with patient sera and the most antigenic was further assessed for its serodiagnostic potential by indirect enzyme-linked immunosorbent assay (ELISA). The ELISA based on the recombinant protein was equivalent in sensitivity to the commercial test (Serodia Myco II; Fujirebio Inc.) to which it was compared. Southern and Western blotting data suggested that the recombinant protein derived from the 116-kDa protein of M. pneumoniae could provide a species-specific diagnostic tool, although further assessment is required. PMID:10074521

  14. A Probability Model of Accuracy in Deception Detection Experiments.

    ERIC Educational Resources Information Center

    Park, Hee Sun; Levine, Timothy R.

    2001-01-01

    Extends the recent work on the veracity effect in deception detection. Explains the probabilistic nature of a receiver's accuracy in detecting deception and analyzes a receiver's detection of deception in terms of set theory and conditional probability. Finds that accuracy is shown to be a function of the relevant conditional probability and the…

  15. A Probability Model of Accuracy in Deception Detection Experiments.

    ERIC Educational Resources Information Center

    Park, Hee Sun; Levine, Timothy R.

    2001-01-01

    Extends the recent work on the veracity effect in deception detection. Explains the probabilistic nature of a receiver's accuracy in detecting deception and analyzes a receiver's detection of deception in terms of set theory and conditional probability. Finds that accuracy is shown to be a function of the relevant conditional probability and the…

  16. Indirect genomic effects on survival from gene expression data

    PubMed Central

    Ferkingstad, Egil; Frigessi, Arnoldo; Lyng, Heidi

    2008-01-01

    In cancer, genes may have indirect effects on patient survival, mediated through interactions with other genes. Methods to study the indirect effects that contribute significantly to survival are not available. We propose a novel methodology to detect and quantify indirect effects from gene expression data. We discover indirect effects through several target genes of transcription factors in cancer microarray data, pointing to genetic interactions that play a significant role in tumor progression. PMID:18358079

  17. A critical review of peripheral arterial tone and pulse transit time as indirect diagnostic methods for detecting sleep disordered breathing and characterizing sleep structure.

    PubMed

    Pépin, Jean-Louis; Tamisier, Renaud; Borel, Jean-Christian; Baguet, Jean-Phillipe; Lévy, Patrick

    2009-11-01

    Sympathetic activity varies continuously across sleep stages. During rapid eye movement sleep, sympathetic tone increases substantially but is highly variable. Microarousals are associated with momentary bursts of sympathetic activity. Abnormal respiratory events progressively elevate sympathetic activity in proportion to the severity of oxyhemoglobin desaturation. These phenomena imply that cardiovascular markers of sympathetic activity such as peripheral arterial tone (PAT) and pulse transit time could be indirect tools for diagnosing sleep disordered breathing and characterizing sleep structure and fragmentation. Measurement of variations in PAT coupled with pulse rate accelerations and desaturations in oximetry can be used to diagnose sleep apnea. Good agreement between both manually and automatically analyzed PAT recordings and polysomnography has been demonstrated during in-laboratory or at-home studies. Numerous validation studies against esophageal pressure have demonstrated that pulse transit time is the best noninvasive method for measurement of respiratory effort. Pulse transit time and PAT are sensitive techniques for arousal recognition, particularly in children and infants. There are specific sleep stage-dependent PAT patterns that allow for the recognition of rapid eye movement sleep and, in the case of nonrapid eye movement sleep, the separation of lighter stages from deeper, slow wave sleep. Elevated nocturnal sympathetic activity as documented by PAT attenuations is linked with chronically elevated blood pressure in humans. Cardiovascular markers of autonomic control during sleep permit not only the diagnosis of obstructive sleep apnea and estimation of sleep structure but are also linked with the prevalence of daytime hypertension.

  18. ASTERIA: A Balloon-Borne Experiment for Infrasound Detection

    NASA Astrophysics Data System (ADS)

    Young, Eliot; Wahl, Kerry; Ballard, Courtney; Daugherty, Emily; Dullea, Connor; Garner, Kyle; Heaney, Martin; Thom, Ian; Von Hendy, Michael; Young, Emma; Diller, Jed; Dischner, Zach; Drob, Douglas; Boslough, Mark; Brown, Peter

    2015-04-01

    ASTERIA (Aloft Stratospheric Testbed for Experimental Research on Infrasonic Activity) is a small (<20 kg) payload designed to measure infrasound disturbances from a balloon-borne platform at altitudes near 60,000 ft (~20 km). A balloon platform is expected to have two advantages over ground-based infrasound stations: a relatively benign wind environment and exposure to higher signal strengths within a stratospheric duct. ASTERIA's nominal sensitivity requirements are to measure waves between 0.1 to 20 Hz at the 0.1 Pa level with signal-to-noise ratios of 5 or better. At the time of this writing, we have tested wave sensors based on the differential pressure transducers recently flown by Bowman et al. (2014) on a NASA/HASP (High Altitude Student Payload); our modified pressure sensor was tested in a NOAA piston-bellows facility in Boulder, CO. Our goal of characterizing 0.1 Pa amplitude waves requires that combined noise sources are below the the 0.02 Pa rms level. ASTERIA carries five differential transducers with port inlets arranged a diamond-like pattern (one zenith- and one nadir-facing port, plus three horizontal ports equally spaced in azimuth). Baffling for these sensors is a hybrid of perforated tubing and porous barriers, as described in Hedlin (2014). Other noise sources of concern include the electronic amplification of the transducer voltages and low-frequency pressure waves caused by pendulum or twisting modes of the payload. We will report on our plans to characterize and reduce these noise sources. The ASTERIA payload is intended to fly on long-duration super-pressure balloons for intervals of ~100 days. We plan to conduct an experiment in the summer or fall of 2015 in which a calibrated disturbance is set off and detected simultaneously from stratospheric ASTERIA payloads and ground-based stations. References: 1) Bowman et al. 2014, "Balloons over Volcanoes Scientific Report," HASP 2014 final report. 2) Hedlin 2003, "Infrasonic Wind-noise Reduction

  19. Social cognition of indirect speech: Evidence from Parkinson's Disease.

    PubMed

    McNamara, Patrick; Holtgraves, Thomas; Durso, Raymon; Harris, Erica

    2010-03-01

    We examined potential neurocognitive mechanisms of indirect speech in support of face management in 28 patients with Parkinson's disease (PD) and 32 elderly controls with chronic disease. In experiment 1, we demonstrated automatic activation of indirect meanings of particularized implicatures in controls but not in PD patients. Failure to automatically engage comprehension of indirect meanings of indirect speech acts in PD patients was correlated with a measure of prefrontal dysfunction. In experiment 2, we showed that while PD patients and controls offered similar interpretations of indirect speech acts, PD participants were overly confident in their interpretations and unaware of errors of interpretation. Efficient reputational adjustment mechanisms apparently require intact striatal-prefrontal networks.

  20. Resource Construction and Evaluation for Indirect Opinion Mining of Drug Reviews

    PubMed Central

    Noferesti, Samira; Shamsfard, Mehrnoush

    2015-01-01

    Opinion mining is a well-known problem in natural language processing that has attracted increasing attention in recent years. Existing approaches are mainly limited to the identification of direct opinions and are mostly dedicated to explicit opinions. However, in some domains such as medical, the opinions about an entity are not usually expressed by opinion words directly, but they are expressed indirectly by describing the effect of that entity on other ones. Therefore, ignoring indirect opinions can lead to the loss of valuable information and noticeable decline in overall accuracy of opinion mining systems. In this paper, we first introduce the task of indirect opinion mining. Then, we present a novel approach to construct a knowledge base of indirect opinions, called OpinionKB, which aims to be a resource for automatically classifying people’s opinions about drugs. Using our approach, we have extracted 896 quadruples of indirect opinions at a precision of 88.08 percent. Furthermore, experiments on drug reviews demonstrate that our approach can achieve 85.25 percent precision in polarity detection task, and outperforms the state-of-the-art opinion mining methods. We also build a corpus of indirect opinions about drugs, which can be used as a basis for supervised indirect opinion mining. The proposed approach for corpus construction achieves the precision of 88.42 percent. PMID:25962135

  1. Resource construction and evaluation for indirect opinion mining of drug reviews.

    PubMed

    Noferesti, Samira; Shamsfard, Mehrnoush

    2015-01-01

    Opinion mining is a well-known problem in natural language processing that has attracted increasing attention in recent years. Existing approaches are mainly limited to the identification of direct opinions and are mostly dedicated to explicit opinions. However, in some domains such as medical, the opinions about an entity are not usually expressed by opinion words directly, but they are expressed indirectly by describing the effect of that entity on other ones. Therefore, ignoring indirect opinions can lead to the loss of valuable information and noticeable decline in overall accuracy of opinion mining systems. In this paper, we first introduce the task of indirect opinion mining. Then, we present a novel approach to construct a knowledge base of indirect opinions, called OpinionKB, which aims to be a resource for automatically classifying people's opinions about drugs. Using our approach, we have extracted 896 quadruples of indirect opinions at a precision of 88.08 percent. Furthermore, experiments on drug reviews demonstrate that our approach can achieve 85.25 percent precision in polarity detection task, and outperforms the state-of-the-art opinion mining methods. We also build a corpus of indirect opinions about drugs, which can be used as a basis for supervised indirect opinion mining. The proposed approach for corpus construction achieves the precision of 88.42 percent.

  2. Neural processing associated with comprehension of an indirect reply during a scenario reading task.

    PubMed

    Shibata, Midori; Abe, Jun-ichi; Itoh, Hiroaki; Shimada, Koji; Umeda, Satoshi

    2011-11-01

    In daily communication, we often use indirect speech to convey our intention. However, little is known about the brain mechanisms that underlie the comprehension of indirect speech. In this study, we conducted a functional MRI experiment using a scenario reading task to compare the neural activity induced by an indirect reply (a type of indirect speech) and a literal sentence. Participants read a short scenario consisting of three sentences. The first two sentences explained the situation of the protagonists, whereas the third sentence had an indirect, literal, or unconnected meaning. The indirect reply condition primarily activated the bilateral fronto-temporal networks (Brodmann's Areas (BA) 47 and 21) and the dorso-medial prefrontal cortex (dmPFC). In the literal sentence condition, only the left fronto-temporal network (BA 45 and 21) and the dmPFC (posterior region) were activated. In addition, we found greater activation resulting from comprehension of an indirect reply than from literal sentence comprehension in the dmPFC, the left middle frontal area (BA 9), the bilateral inferior frontal area (BA 9/47), and the right middle temporal area (BA 21). Our findings indicate that the right and left fronto-temporal networks play a crucial role in detecting contextual violations, whereas the medial frontal cortex is important for generating inferences to make sense of remarks within a context. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Development and use of an indirect enzyme-linked immunosorbent assay for detection of iridovirus exposure in gopher tortoises (Gopherus polyphemus) and eastern box turtles (Terrapene carolina carolina).

    PubMed

    Johnson, April J; Wendland, Lori; Norton, Terry M; Belzer, Bill; Jacobson, Elliott R

    2010-05-19

    Iridoviruses, pathogens typically associated with fish and amphibians, have recently been shown to cause acute respiratory disease in chelonians including box turtles, red-eared sliders, gopher tortoises, and Burmese star tortoises. Case reports of natural infections in several chelonian species in the United States have been reported, however the prevalence remains unknown in susceptible populations of free-ranging chelonians. To determine the prevalence of iridovirus exposure in free-ranging gopher tortoises (Gopherus polyphemus) in the southeast United States, an indirect enzyme-linked immunosorbent assay (ELISA) was developed and used to evaluate plasma samples from wild gopher tortoises (G. polyphemus) from: Alabama (n=9); Florida (n=658); Georgia (n=225); Louisiana (n=12); Mississippi (n=28); and unknown locations (68) collected between 2001 and 2006. Eight (1.2%) seropositive tortoises were identified from Florida and seven (3.1%) from Georgia for an overall prevalence of 1.5%. Additionally, a population of eastern box turtles was sampled from a private nature sanctuary in Pennsylvania that experienced an outbreak of iridovirus the previous year, which killed 16 turtles. Only 1 turtle out of 55 survivors tested positive (1.8%). Results suggest a low exposure rate in chelonians to this pathogen; however, it is suspected that this is an underestimate of the true prevalence. Since experimental transmission studies and past outbreaks have shown a high rate of mortality in infected turtles, turtles may die before they develop an antibody response. Further, the duration of the antibody response is unknown and may also cause an underestimate of the true prevalence. Copyright 2009 Elsevier B.V. All rights reserved.

  4. Detection of ATP and NADH: A Bioluminescent Experience.

    ERIC Educational Resources Information Center

    Selig, Ted C.; And Others

    1984-01-01

    Described is a bioluminescent assay for adenosine triphosphate (ATP) and reduced nicotineamide-adenine dinucleotide (NADH) that meets the requirements of an undergraduate biochemistry laboratory course. The 3-hour experiment provides students with experience in bioluminescence and analytical biochemistry yet requires limited instrumentation,…

  5. Detection of ATP and NADH: A Bioluminescent Experience.

    ERIC Educational Resources Information Center

    Selig, Ted C.; And Others

    1984-01-01

    Described is a bioluminescent assay for adenosine triphosphate (ATP) and reduced nicotineamide-adenine dinucleotide (NADH) that meets the requirements of an undergraduate biochemistry laboratory course. The 3-hour experiment provides students with experience in bioluminescence and analytical biochemistry yet requires limited instrumentation,…

  6. Microwave detection of air showers with the MIDAS experiment

    NASA Astrophysics Data System (ADS)

    Privitera, Paolo; Alekotte, I.; Alvarez-Muñiz, J.; Berlin, A.; Bertou, X.; Bogdan, M.; Boháčová, M.; Bonifazi, C.; Carvalho, W. R.; de Mello Neto, J. R. T.; Facal San Luis, P.; Genat, J. F.; Hollon, N.; Mills, E.; Monasor, M.; Reyes, L. C.; Rouille d'Orfeuil, B.; Santos, E. M.; Wayne, S.; Williams, C.; Zas, E.

    2011-03-01

    Microwave emission from Extensive Air Showers could provide a novel technique for ultra-high energy cosmic rays detection over large area and with 100% duty cycle. We describe the design, performance and first results of the MIDAS (MIcrowave Detection of Air Showers) detector, a 4.5 m parabolic dish with 53 feeds in its focal plane, currently installed at the University of Chicago.

  7. Constrained sampling experiments reveal principles of detection in natural scenes.

    PubMed

    Sebastian, Stephen; Abrams, Jared; Geisler, Wilson S

    2017-07-11

    A fundamental everyday visual task is to detect target objects within a background scene. Using relatively simple stimuli, vision science has identified several major factors that affect detection thresholds, including the luminance of the background, the contrast of the background, the spatial similarity of the background to the target, and uncertainty due to random variations in the properties of the background and in the amplitude of the target. Here we use an experimental approach based on constrained sampling from multidimensional histograms of natural stimuli, together with a theoretical analysis based on signal detection theory, to discover how these factors affect detection in natural scenes. We sorted a large collection of natural image backgrounds into multidimensional histograms, where each bin corresponds to a particular luminance, contrast, and similarity. Detection thresholds were measured for a subset of bins spanning the space, where a natural background was randomly sampled from a bin on each trial. In low-uncertainty conditions, both the background bin and the amplitude of the target were fixed, and, in high-uncertainty conditions, they varied randomly on each trial. We found that thresholds increase approximately linearly along all three dimensions and that detection accuracy is unaffected by background bin and target amplitude uncertainty. The results are predicted from first principles by a normalized matched-template detector, where the dynamic normalizing gain factor follows directly from the statistical properties of the natural backgrounds. The results provide an explanation for classic laws of psychophysics and their underlying neural mechanisms.

  8. Diagnostic performance of an indirect enzyme-linked immunosorbent assay (ELISA) to detect bovine leukemia virus antibodies in bulk-tank milk samples

    PubMed Central

    Nekouei, Omid; Durocher, Jean; Keefe, Greg

    2016-01-01

    This study assessed the diagnostic performance of a commercial ELISA for detecting bovine leukemia virus antibodies in bulk-tank milk samples from eastern Canada. Sensitivity and specificity of the test were estimated at 97.2% and 100%, respectively. The test was recommended as a cost-efficient tool for large-scale screening programs. PMID:27429469

  9. A novel modified-indirect ELISA based on spherical body protein 4 for detecting antibody during acute and long-term infections with diverse babesia bovis strains

    USDA-ARS?s Scientific Manuscript database

    Background: Cattle persistently infected with Babesia bovis are reservoirs for intra- and inter-herd transmission. Since B. bovis is considered a persistent infection, developing a reliable, high-throughput assay that detects antibody during all stages of the infection could be pivotal for establish...

  10. Development of an Indirect ELISA Using Different Fragments of Recombinant Ncgra7 for Detection of Neospora caninum Infection in Cattle and Water Buffalo

    PubMed Central

    HAMIDINEJAT, Hossein; SEIFI ABAD SHAPOURI, Massoud Reza; NAMAVARI, Mohammad Mehdi; SHAYAN, Parviz; KEFAYAT, Marzieh

    2015-01-01

    Background: Dense granules are immunodominant proteins for the standardization of immunodiagnostic procedures to detect neosporosis. In the presented study different fragment of a dense-granule protein was evaluated for serodiagnosis of Neospora caninum in cattle and water buffalo. Methods: NcGRA7, from N. caninum tachyzoites was amplified. PCR product and pMAL-c2X plasmid were digested with EcoR1 restriction enzyme and expressed in Escherichia coli to evaluate its competence for detection of anti- N. caninum antibodies with ELISA in comparison with commercial IDEXX ELISA. Furthermore, 230 sera of presumably healthy cattle and water buffaloes (108 cattle and 122 water buffaloes) were analyzed by both tests to determine the agreement of these two procedures. Results: Sensitivities and specificities of NcGRA7-based ELISA were 94.64% and 90.38% respectively using sera of cattle, but were 98.57% and 86.54% in the case of buffaloes respectively. A good correlation between the results of IDEXX ELISA and ELISA based on recombinant NcGRA7 for detecting N. caninum antibodies was appeared. Analyzing by Mc Nemar′s showed that NcGRA7-based ELISA has acceptable capability to differentiate the positive results in comparison with IDEXX ELISA. Conclusion: NcGRA7-based ELISA considering utilized new fragment of genomic DNA is a good tool for serodiagnosis of anti- N. caninum antibodies for screening and epidemiological purposes on cattle herd and water buffaloes as well. PMID:25904948

  11. Lateral flow immunoassay with upconverting nanoparticle-based detection for indirect measurement of interferon response by the level of MxA.

    PubMed

    Juntunen, Etvi; Salminen, Teppo; Talha, Sheikh M; Martiskainen, Iida; Soukka, Tero; Pettersson, Kim; Waris, Matti

    2017-04-01

    Myxovirus resistance protein A (MxA) is a biomarker of interferon-induced gene expression state involved in many viral infections and some autoimmune disorders. It has a variety of potential utilities in clinical diagnostics, including distinguishing between bacterial and viral infections. Currently, MxA-assays are used for monitoring of IFN-β therapy in multiple sclerosis (MS) patients. As a proof-of-concept for rapid quantitative measurement of interferon response, a lateral flow immunoassay (LFIA) with upconverting nanoparticle (UCNP) reporters was developed and evaluated with clinical whole blood samples to assess the potential for a rapid and user-friendly quantitative assay for MxA, since the currently available rapid test for MxA (FebriDX) produces only qualitative result. The high detection sensitivity enabled by the UCNP reporter technology allowed the sample pre-treatment with dilution of whole blood into lysis buffer at a detectable analyte concentration. The assay can be done within 2 hr and the results correlate with the reference MxA-ELISA, which requires an overnight incubation. With 36 samples, R(2) for linear regression was 0.86. The assay detected 96% of the IFN-β responders with 89% specificity using a cut-off level of 100 μg/L for an elevated MxA-concentration. J. Med. Virol. 89:598-605, 2017. © 2016 Wiley Periodicals, Inc.

  12. Experiments in Coherent Change Detection for Synthetic Aperture Sonar

    DTIC Science & Technology

    2010-06-01

    over time. ACD techniques, long used in airborne radar applications, are just beginning to be applied to sidescan sonar . In Coherent Change Detection...accurate geo- registration), the complexity of the propagation environment, and the radiometric inconsistencies of conventional sidescan sonars ...will follow suit. As conventional sidescan sonars exhibit resolution that degrades with range and are typically limited to creation of backscatter

  13. Parallel detection experiment of fluorescence confocal microscopy using DMD.

    PubMed

    Wang, Qingqing; Zheng, Jihong; Wang, Kangni; Gui, Kun; Guo, Hanming; Zhuang, Songlin

    2016-05-01

    Parallel detection of fluorescence confocal microscopy (PDFCM) system based on Digital Micromirror Device (DMD) is reported in this paper in order to realize simultaneous multi-channel imaging and improve detection speed. DMD is added into PDFCM system, working to take replace of the single traditional pinhole in the confocal system, which divides the laser source into multiple excitation beams. The PDFCM imaging system based on DMD is experimentally set up. The multi-channel image of fluorescence signal of potato cells sample is detected by parallel lateral scanning in order to verify the feasibility of introducing the DMD into fluorescence confocal microscope. In addition, for the purpose of characterizing the microscope, the depth response curve is also acquired. The experimental result shows that in contrast to conventional microscopy, the DMD-based PDFCM system has higher axial resolution and faster detection speed, which may bring some potential benefits in the biology and medicine analysis. SCANNING 38:234-239, 2016. © 2015 Wiley Periodicals, Inc.

  14. Real-time elastography for detecting prostate cancer: preliminary experience.

    PubMed

    Pallwein, Leo; Mitterberger, Michael; Struve, Peter; Pinggera, Germar; Horninger, Wolfgang; Bartsch, Georg; Aigner, Friedrich; Lorenz, Andreas; Pedross, Florian; Frauscher, Ferdinand

    2007-07-01

    To assess the use of real-time elastography (RTE) for detecting prostate cancer in patients scheduled for radical prostatectomy (RP), as most solid tumours differ in their consistency from the deriving tissue, and RTE might offer a new tool for cancer detection. We examined 15 patients (mean age 56 years, sd 6.2, range 46-71) with RTE, using an ultrasonography (US) system with a 7.5-MHz transrectal probe as a transducer. RTE is capable of visualizing displacements between pairs of US images of tissues when placed under axial compression. The stiffness of the lesion was displayed from blue (soft) to black (hard). Hard lesions with a diameter of > or = 5 mm were considered as malignant. All patients had the diagnosis of prostate cancer confirmed by biopsy and had a mean (range) prostate specific antigen (PSA) level of 4.6 (1.4-16.1) ng/mL; all were scheduled for RP. US was performed by two investigators and interpreted by consensus. Cancer location and size was determined in the RTE mode only. One pathologist classified tumour location, grade and stage. The RTE findings were compared with the pathological findings. There were no major complications during RP in any patient; all had a pT2 tumour on histopathological examination, the Gleason score was 5-9 and the mean (range) tumour size 1.1 (0.6-2.5) cm. Thirty-five foci of prostate cancer were present at the pathological evaluation; multiple foci were found in 11 of the 15 glands. RTE detected 28 of 35 cancer foci (sensitivity 80%). The per-patient analysis showed that RTE detected at least one cancer area in each of the 15 patients. Only four sites with false-positive findings on RTE and no histopathological correlation were detected; these findings were obtained in the first five patients (period of learning). RTE can be used to visualize differences in tissue elasticity. Our results show that RTE allows the detection of prostate cancer and estimation of tumour location and size. RTE of the prostate is a new

  15. Indirect reciprocity with trinary reputations.

    PubMed

    Tanabe, Shoma; Suzuki, Hideyuki; Masuda, Naoki

    2013-01-21

    Indirect reciprocity is a reputation-based mechanism for cooperation in social dilemma situations when individuals do not repeatedly meet. The conditions under which cooperation based on indirect reciprocity occurs have been examined in great details. Most previous theoretical analysis assumed for mathematical tractability that an individual possesses a binary reputation value, i.e., good or bad, which depends on their past actions and other factors. However, in real situations, reputations of individuals may be multiple valued. Another puzzling discrepancy between the theory and experiments is the status of the so-called image scoring, in which cooperation and defection are judged to be good and bad, respectively, independent of other factors. Such an assessment rule is found in behavioral experiments, whereas it is known to be unstable in theory. In the present study, we fill both gaps by analyzing a trinary reputation model. By an exhaustive search, we identify all the cooperative and stable equilibria composed of a homogeneous population or a heterogeneous population containing two types of players. Some results derived for the trinary reputation model are direct extensions of those for the binary model. However, we find that the trinary model allows cooperation under image scoring under some mild conditions.

  16. Indirect resin composites

    PubMed Central

    Nandini, Suresh

    2010-01-01

    Aesthetic dentistry continues to evolve through innovations in bonding agents, restorative materials, and conservative preparation techniques. The use of direct composite restoration in posterior teeth is limited to relatively small cavities due to polymerization stresses. Indirect composites offer an esthetic alternative to ceramics for posterior teeth. This review article focuses on the material aspect of the newer generation of composites. This review was based on a PubMed database search which we limited to peer-reviewed articles in English that were published between 1990 and 2010 in dental journals. The key words used were ‘indirect resin composites,’ composite inlays,’ and ‘fiber-reinforced composites.’ PMID:21217945

  17. Searching for Dark Matter in Unification Models: A Hint from Indirect Sensitivities towards Future Signals in Direct Detection and B-decays

    SciTech Connect

    Olive, Keith A.

    2006-11-28

    A comparison is made between accelerator and direct detection constraints in constrained versions of the minimal supersymmetric standard model. Models considered are based on mSUGRA, where scalar and gaugino masses are unified at the GUT scale. In addition, the mSUGRA relation between the (unified) A and B parameters is assumed, as is the relation between m0 and gravitino mass. Also considered are models where the latter two conditions are dropped (the CMSSM), and a less constrained version where the Higgs soft masses are not unified at the GUT scale (the NUHM)

  18. Bipolar Transistors Can Detect Charge in Electrostatic Experiments

    ERIC Educational Resources Information Center

    Dvorak, L.

    2012-01-01

    A simple charge indicator with bipolar transistors is described that can be used in various electrostatic experiments. Its behaviour enables us to elucidate links between 'static electricity' and electric currents. In addition it allows us to relate the sign of static charges to the sign of the terminals of an ordinary battery. (Contains 7 figures…

  19. Bipolar Transistors Can Detect Charge in Electrostatic Experiments

    ERIC Educational Resources Information Center

    Dvorak, L.

    2012-01-01

    A simple charge indicator with bipolar transistors is described that can be used in various electrostatic experiments. Its behaviour enables us to elucidate links between 'static electricity' and electric currents. In addition it allows us to relate the sign of static charges to the sign of the terminals of an ordinary battery. (Contains 7 figures…

  20. Emergency First Responders' Experience with Colorimetric Detection Methods

    SciTech Connect

    Sandra L. Fox; Keith A. Daum; Carla J. Miller; Marnie M. Cortez

    2007-10-01

    Nationwide, first responders from state and federal support teams respond to hazardous materials incidents, industrial chemical spills, and potential weapons of mass destruction (WMD) attacks. Although first responders have sophisticated chemical, biological, radiological, and explosive detectors available for assessment of the incident scene, simple colorimetric detectors have a role in response actions. The large number of colorimetric chemical detection methods available on the market can make the selection of the proper methods difficult. Although each detector has unique aspects to provide qualitative or quantitative data about the unknown chemicals present, not all detectors provide consistent, accurate, and reliable results. Included here, in a consumer-report-style format, we provide “boots on the ground” information directly from first responders about how well colorimetric chemical detection methods meet their needs in the field and how they procure these methods.

  1. The Cloud Detection and UV Monitoring Experiment (CLUE)

    NASA Technical Reports Server (NTRS)

    Barbier, L.; Loh, E.; Sokolsky, P.; Streitmatter, R.

    2004-01-01

    We propose a large-area, low-power instrument to perform CLoud detection and Ultraviolet monitoring, CLUE. CLUE will combine the W detection capabilities of the NIGHTGLOW payload, with an array of infrared sensors to perform cloud slicing measurements. Missions such as EUSO and OWL which seek to measure UHE cosmic-rays at 1W20 eV use the atmosphere as a fluorescence detector. CLUE will provide several important correlated measurements for these missions, including: monitoring the atmospheric W emissions &om 330 - 400 nm, determining the ambient cloud cover during those W measurements (with active LIDAR), measuring the optical depth of the clouds (with an array of narrow band-pass IR sensors), and correlating LIDAR and IR cloud cover measurements. This talk will describe the instrument as we envision it.

  2. Adjusting inequalities for detection-loophole-free steering experiments

    NASA Astrophysics Data System (ADS)

    Sainz, Ana Belén; Guryanova, Yelena; McCutcheon, Will; Skrzypczyk, Paul

    2016-09-01

    We study the problem of certifying quantum steering in a detection-loophole-free manner in experimental situations that require postselection. We present a method to find the modified local-hidden-state bound of steering inequalities in such a postselected scenario. We then present a construction of linear steering inequalities in arbitrary finite dimension and show that they certify steering in a loophole-free manner as long as the detection efficiencies are above the known bound below which steering can never be demonstrated. We also show how our method extends to the scenarios of multipartite steering and Bell nonlocality, in the general case where there can be correlations between the losses of the different parties. In both cases we present examples to demonstrate the techniques developed.

  3. Experience with airborne detection of radioactive pollution (ENMOS, IRIS).

    PubMed

    Pavlik, Bohuslav; Engelsmann, Jan

    2004-01-01

    This paper discusses the advantages of airborne monitoring of radioactive pollution and shows example maps indicating manmade pollution from different sources. The sensitivity of airborne radioactive detection is discussed. Comparisons of airborne and different ground measurements are presented. New instrumentation for airborne or ground moving vehicles is briefly described. Airborne footprinting provides rapid, well-defined spatial images of natural and manmade radioactive contamination. Data acquisition integrated with GPS navigation provides consistent data and guarantees proper data location. Real-time airborne measurements are re-calculated, with the use of special algorithms, into absolute units for individual radioactive nuclei contamination of the ground together with dose calculation. Raw records and calculated data are provided after enhanced post-flight processing. Dose rates and detection of different radioactive elements are presented. (ENMOS is a product of Picodas Group Inc. and IRIS is the product of Pico Envirotec Inc.)

  4. The Cloud Detection and UV Monitoring Experiment (CLUE)

    NASA Technical Reports Server (NTRS)

    Barbier, L.; Loh, E.; Sokolsky, P.; Streitmatter, R.

    2004-01-01

    We propose a large-area, low-power instrument to perform CLoud detection and Ultraviolet monitoring, CLUE. CLUE will combine the W detection capabilities of the NIGHTGLOW payload, with an array of infrared sensors to perform cloud slicing measurements. Missions such as EUSO and OWL which seek to measure UHE cosmic-rays at 1W20 eV use the atmosphere as a fluorescence detector. CLUE will provide several important correlated measurements for these missions, including: monitoring the atmospheric W emissions &om 330 - 400 nm, determining the ambient cloud cover during those W measurements (with active LIDAR), measuring the optical depth of the clouds (with an array of narrow band-pass IR sensors), and correlating LIDAR and IR cloud cover measurements. This talk will describe the instrument as we envision it.

  5. Experiments on the use of CCD's to detect photoelectron images

    NASA Technical Reports Server (NTRS)

    Choisser, J. P.

    1975-01-01

    Image tube design and processing requirements for building an ICCD are discussed. Work is under way at EVC for building an ICCD using the Fairchild CCD 201 (100 x 100) array, and progress will be reported. Demountable tests have been made, exposing parts of a CCD 201 to 15 kilovolt electrons over five radiation levels from approximately 10 to 1 million rads. Other tubes built by EVC over the last few years which successfully use semiconductors to detect photoelectrons will be described briefly.

  6. Theileria annae (syn. Babesia microti-like) infection in dogs in NW Spain detected using direct and indirect diagnostic techniques: clinical report of 75 cases.

    PubMed

    Miró, Guadalupe; Checa, Rocío; Paparini, Andrea; Ortega, Nieves; González-Fraga, José Luís; Gofton, Alex; Bartolomé, Adrián; Montoya, Ana; Gálvez, Rosa; Mayo, Pedro Pablo; Irwin, Peter

    2015-04-10

    In north-western Spain, piroplamosis caused by Theileria annae is now recognized as a serious problem because veterinarians, despite being aware of the clinical signs of piroplasmosis, lack the necessary information on its epidemiology or specific diagnostic tools for its management. This, along with the fact that T. annae infection is also refractory to current piroplamosis treatments, prompted this study designed to assess the clinical presentation and diagnosis of this largely unknown parasitic disease in dogs. One hundred and twenty dogs in NW Spain suspected clinically of having piroplasmosis were examined and piroplasm species detected by light microscopy (LM) observation of Giemsa-stained blood smears, immunofluorescent antibody test (IFAT), and PCR plus sequencing. Seventy five of the sick dogs were confirmed to be infected with T. annae by PCR (designated "true infection cases"). Intraerythrocytic ring-shaped bodies morphologically compatible with small piroplasms were observed by LM in 59 (57 true infections) of the 120 blood samples. Anti-Babesia antibodies were detected by IFAT in 59 of the 120 sera (55 of which were "true infections"). Using PCR as the reference method, moderate agreement was observed between positive LM vs PCR and IFAT vs PCR results (kappa values: 0.6680 and 0.6017, respectively). Microscopy examination and IFAT were moderately sensitive in detecting the pathogen (76% and 73.3%, respectively). In the 75 cases of "true infection", the most common clinical signs observed were pale mucous membranes, anorexia and apathy. Blood cell counts consistently revealed severe regenerative anaemia and thrombocytopenia in dogs with piroplasmosis due to T. annae. Young dogs (≤3 year) (p = 0.0001) were more susceptible to the disease. Microscopy showed moderate diagnostic sensitivity for acute T. annae infection while IFAT-determined antibody titres were low (1/64 to 1/128). The infecting species should be therefore confirmed by molecular tests

  7. Development and Application of an Indirect Competitive Enzyme-Linked Immunosorbent Assay for the Detection of p,p′-DDE in Human Milk and Comparison of the Results against GC-ECD

    PubMed Central

    Hongsibsong, Surat; Wipasa, Jiraprapa; Pattarawarapan, Mookda; Chantara, Somporn; Stuetz, Wolfgang; Nosten, Francois; Prapamontol, Tippawan

    2012-01-01

    1,1-Dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p′-DDE) is the major metabolite of insecticide 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (p,p′-DDT) and a persistent organic pollutant (POPs) with concerns regarding its bioaccumulation and persistence in the environment and food chain. In the present study, an indirect competitive enzyme-linked immunosorbant assay (ic-ELISA) specific for the detection of p,p′-DDE is described. In hapten synthesis, 2,2′-bis(4-chlorophenyl)ethanol and glutaric anhydride were used as precursor and spacer arm, respectively. The hapten was then conjugated to bovine serum albumin (BSA) as immunogen for mouse immunization and also conjugated to ovalbumin as coating antigen for ELISA. The developed ic-ELISA was used for detecting p,p′-DDE in human milk samples and validated against the results from conventional gas chromatography–electron capture detection (GC-ECD). Coefficients of variation (%CV) of ELISA were 5.7–10.4% for intra-assay and 10.6–19.6% for interassay variations. The Pearson correlation coefficient of p,p′-DDE concentrations between ic-ELISA and GC-ECD was r = 0.766, which was in an acceptable range. The results indicate that the developed assay could be an alternative analytical tool for monitoring p,p′-DDE in lipimic matrices such as human milk. PMID:22122759

  8. Unexploded ordnance detection experiments using ultrawideband synthetic aperture radar

    NASA Astrophysics Data System (ADS)

    DeLuca, Clyde C.; Marinelli, Vincent R.; Ressler, Marc A.; Ton, Tuan T.

    1998-09-01

    The Army Research Laboratory (ARL) has several technology development programs that are evaluating the use of ultra- wideband synthetic aperture radar (UWB SAR) to detect and locate targets that are subsurface or concealed by foliage. Under these programs, a 1-GHz-bandwidth, low-frequency, fully polarimetric UWB SAR instrumentation system was developed to collect the data needed to support foliage and ground- penetrating radar studies. The radar was integrated onto a 150-ft-high mobile boomlift platform in 1995 and was thus named the BoomSAR. In 1997, under the sponsorship of the Strategic Environmental Research and Development Program (SERDP), ARL began a project focused on enhancing the detection and discrimination of unexploded ordnance (UXO). The program's technical approach is to collect high-quality, precision data to support phenomenological investigations of electromagnetic wave propagation through varying dielectric media, which in turn supports the development of algorithms for automatic target detection. For this project, a UXO test site was set up at the Steel Crater Test Area -- an existing test site that already contained subsurface mines, tactical vehicles, 55-gallon drums, storage containers, wires, pipes, and arms caches located at Yuma Proving Ground (YPG), Arizona. More than 600 additional pieces of inert UXO were added to the Steel Crater Test Area, including bombs (250, 500, 750, 1000, and 2000 lb), mortars (60 and 81 mm), artillery shells (105 and 155 mm), 2.75-in. rockets, submunitions (M42, BLU-63, M68, BLU-97, and M118), and mines (Gator, VS1.6, M12, PMN, and POM- Z). In the selection of UXO to be included at YPG, an emphasis was placed on the types of munitions that may be present at CONUS test and training ranges.

  9. First detection of extensive air showers with the EEE experiment

    NASA Astrophysics Data System (ADS)

    Moro, R.

    2011-03-01

    The Extreme Energy Events (EEE) Project is devoted to the study of extremely high energy cosmic rays by means of an array of particle detectors distributed all over the Italian territory. Each element of the array (called telescope in the following) is installed in a High School, with the further goal to introduce students to particle and astroparticle physics, and consists of three Multigap Resistive Plate Chambers (MRPC), that have excellent time resolution and good tracking capability. In this paper the first results on the detection of extensive air showers by means of time coincidences between two telescopes are presented.

  10. Comparison of enzyme-linked immunosorbent assay, indirect immunofluorescence assay, and virus isolation for detection of respiratory viruses in nasopharyngeal secretions.

    PubMed Central

    Takimoto, S; Grandien, M; Ishida, M A; Pereira, M S; Paiva, T M; Ishimaru, T; Makita, E M; Martinez, C H

    1991-01-01

    Nasopharyngeal secretions obtained from 94 children with acute respiratory illness were examined for the presence of respiratory syncytial virus (RSV), adenovirus, and influenza virus type A by virus culturing (virus isolation technique [VIT]), immunofluorescence assay (IFA), and enzyme-linked immunosorbent assay (ELISA). Similar results were obtained in at least two tests for RSV, influenza virus type A, and adenovirus in 92 (97.9%), 88 (93.6%), and 88 (93.6%) cases, respectively. Both rapid virus detection methods showed good specificity for the diagnosis of these virus infections (greater than or equal to 90.7%) and were more sensitive than was VIT for RSV detection. In a more accurate statistical analysis, the indexes of agreement between VIT and ELISA were substantial for RSV (kappa = 0.69; zeta = 5.5; P less than 0.0001), influenza virus type A (kappa = 0.67; zeta = 5.3; P less than 0.0001), and adenovirus (kappa = 0.71; zeta = 6.0; P less than 0.0001), while it was almost perfect for RSV when ELISA was compared with IFA (kappa = 0.88; zeta = 5.7; P less than 0.0001). Although the observed agreement was good in the comparison of these two tests for these three viruses (89%0, the indexes of agreement were moderate in the comparison of IFA and VIT for RSV (K = 0.55; Z = 2.0; P < 0.05), influenza virus type A (K = 0.42; Z = 9.7; P < 0.0001), and adenovirus (K = 0.41; Z = 6.5; P < 0.0001) and of ELISA and IFA for influenza virus type A (K = 0.55; Z = 7.0; P < 0.0001) and adenovirus (K = 0.59; Z = 6.8; P < 0.0001). All of the statistical evaluations demonstrated better agreement between ELISA and VIT for influenza virus type A and adenovirus. PMID:2037663

  11. Dietary effects on resting metabolic rate in C57BL/6 mice are differentially detected by indirect (O2/CO2 respirometry) and direct calorimetry

    PubMed Central

    Burnett, Colin M.L.; Grobe, Justin L.

    2014-01-01

    Resting metabolic rate (RMR) studies frequently involve genetically-manipulated mice and high fat diets (HFD). We hypothesize that the use of inadequate methods impedes the identification of novel regulators of RMR. This idea was tested by simultaneously measuring RMR by direct calorimetry and respirometry in C57BL/6J mice fed chow, 45% HFD, and then returned to chow. Comparing results during chow feeding uncovered an underestimation of RMR by respirometry (0.010 ± 0.001 kcal/h, P < 0.05), which is equivalent in magnitude to ∼2% of total daily caloric turnover. RMR during 45% HFD feeding was increased by respirometry (+0.013 ± 0.003 kcal/h, P < 0.05), but not direct calorimetry (+0.001 ± 0.002 kcal/h). Both methods indicated that return to chow reduced RMR compared to HFD, though direct calorimetry indicated a reduction below the initial chow fed state (−0.019 ± 0.004 kcal/h versus baseline, P < 0.05) that was not detected by respirometry (−0.003 ± 0.002 kcal/h versus baseline). These results highlight method-specific interpretations of the effects of dietary interventions upon RMR in mice, and prompt the reevaluation of preclinical screening methods used to identify novel RMR modulators. PMID:24944905

  12. Indirect field technology for detecting areas object of illegal spills harmful to human health: application of drones, photogrammetry and hydrological models.

    PubMed

    Capolupo, Alessandra; Pindozzi, Stefania; Okello, Collins; Boccia, Lorenzo

    2014-12-01

    The accumulation of heavy metals in agricultural soils is a serious environmental problem. The Campania region in southern Italy has higher levels of cancer risk, presumably due to the accumulation of geogenic and anthropogenic soil pollutants, some of which have been incorporated into organic matter. The aim of this study was to introduce and test an innovative, field-applicable methodology to detect heavy metal accumulation using drone-based photogrammetry and microrill network modelling, specifically to generate wetlands wetlands prediction indices normally applied at large catchment scales, such as a large geographic basin. The processing of aerial photos taken using a hexacopter equipped with fifth-generation software for photogrammetry allowed the generation of a digital elevation model (DEM) with a resolution as high as 30 mm. Not only this provided a high potential for the study of micro-rill processes, but it was also useful for testing and comparing the capability of the topographic index (TI) and the clima-topographic index (CTI) to predict heavy metal sedimentation points at scales from 0.1 to 10 ha. Our results indicate that the TI and CTI indices can be used to predict points of heavy metal accumulation for small field catchments.

  13. TVA's experience with the SUNYA lightning detection network

    SciTech Connect

    Whitehead, J.; Driggans, R. )

    1990-10-01

    Since 1987 the Tennessee Valley Authority (TVA) has had access to real-time data on cloud-to-ground lightning strikes in its service area through the Lightning Detection Network (LDN) operated by the State University of New York at Albany (SUNYA). Lightning data are displayed in real-time on personal computer workstations connected to SUNYA via satellite link and are recorded for later analysis. TVA is using these data to analyze transmission line outages (real-time and historical), provide warning of approaching lightning to line crews, develop ground flash density maps to replace isokeraunic maps previously used in designing transmission lines for lightning protection, and to learn more about lightning and its effect on TVA's transmission system. Lightning flashes that cause particular line outages have been identified and their current and multiplicity characteristics studied. This information may be used to allow more cost-effective transmission line design in the future.

  14. Indirect detection of pulmonary nodule on low-pass filtered and original x-ray images during limited and unlimited display times

    NASA Astrophysics Data System (ADS)

    Pietrzyk, Mariusz W.; McEntee, Mark; Evanoff, Michael G.; Brennan, Patrick C.

    2012-02-01

    Aim: This study evaluates the assumption that global impression is created based on low spatial frequency components of posterior-anterior chest radiographs. Background: Expert radiologists precisely and rapidly allocate visual attention on pulmonary nodules chest radiographs. Moreover, the most frequent accurate decisions are produced in the shortest viewing time, thus, the first hundred milliseconds of image perception seems be crucial for correct interpretation. Medical image perception model assumes that during holistic analysis experts extract information based on low spatial frequency (SF) components and creates a mental map of suspicious location for further inspection. The global impression results in flagged regions for detailed inspection with foveal vision. Method: Nine chest experts and nine non-chest radiologists viewed two sets of randomly ordered chest radiographs under 2 timing conditions: (1) 300ms; (2) free search in unlimited time. The same radiographic cases of 25 normal and 25 abnormal digitalized chest films constituted two image sets: low-pass filtered and unfiltered. Subjects were asked to detect nodules and rank confidence level. MRMC ROC DBM analyses were conducted. Results: Experts had improved ROC AUC while high SF components are displayed (p=0.03) or while low SF components were viewed under unlimited time (p=0.02) compared with low SF 300mSec viewings. In contrast, non-chest radiologists showed no significant changes when high SF are displayed under flash conditions compared with free search or while low SF components were viewed under unlimited time compared with flash. Conclusion: The current medical image perception model accurately predicted performance for non-chest radiologists, however chest experts appear to benefit from high SF features during the global impression.

  15. A Theory and Experiments for Detecting Shock Locations

    NASA Technical Reports Server (NTRS)

    Hariharan, S. I.; Johnson, D. K.; Adamovsky, G.

    1994-01-01

    In this paper we present a simplified one-dimensional theory for predicting locations of normal shocks in a converging diverging nozzle. The theory assumes that the flow is quasi one-dimensional and the flow is accelerated in the throat area. Optical aspects of the model consider propagation of electromagnetic fields transverse to the shock front. The theory consists of an inverse problem in which from the measured intensity it reconstructs an index of refraction profile for the shock. From this profile and the Dale-Gladstone relation, the density in the flow field is determined, thus determining the shock location. Experiments show agreement with the theory. In particular the location is determined within 10 percent of accuracy. Both the theoretical as well as the experimental results are presented to validate the procedures in this work.

  16. Detection of Drugs in Nails: Three Year Experience.

    PubMed

    Shu, Irene; Jones, Joseph; Jones, Mary; Lewis, Douglas; Negrusz, Adam

    2015-10-01

    Nails (fingernails and toenails) are made of keratin. As the nail grows, substances incorporate into the keratin fibers where they can be detected 3-6 months after use. Samples are collected by clipping of 2-3 mm of nail from all fingers (100 mg). We present drug testing results from 10,349 nail samples collected from high-risk cases during a 3-year period of time. Samples were analyzed by validated analytical methods. The initial testing was performed mostly using enzyme-linked immunosorbent assay, but by liquid chromatography-tandem mass spectrometry (LC-MS-MS) as well. Presumptive positive samples were subjected to confirmatory testing with sample preparation procedures including washing, pulverizing, digestion and extraction optimized for each drug class. The total of 7,799 samples was analyzed for amphetamines. The concentrations ranged from 40 to 572,865 pg/mg (median, 100-3,687) for all amphetamine analytes. Amphetamine and methamphetamine were present in 14% of the samples, 22 samples were positive for 3,4-methylenedioxymethamphetamine (0.3%), 7 for methylenedioxyamphetamine (0.09%) and 4 for 3,4-methylenedioxy-N-ethylamphetamine (0.05%). Cocaine and related analytes were found in 5% samples (7,787 total), and the concentration range was 20-265,063 pg/mg (median 84-1,768). Opioids overall ranged from 40 to 118,229 pg/mg (median 123-830). The most prevalent opioid was oxycodone (15.1%) and hydrocodone (11.4%) compared with 1.0-3.6% for the others, including morphine, codeine, hydromorphone, methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine and oxymorphone. Carboxy-Δ-9-tetrahydrocannabinol positivity rate was 18.1% (0.04-262 pg/mg, median 6.41). Out of 3,039 samples, 756 were positive (24.9%) for ethyl glucuronide (20-3,754 pg/mg, median 88). Other drugs found in nails included barbiturates, benzodiazepines, ketamine, meperidine, tramadol, zolpidem, propoxyphene, naltrexone and buprenorphine. Nail analyses have become a reliable way of determining

  17. Bioechnology of indirect liquefaction

    SciTech Connect

    Datta, R.; Jain, M.K.; Worden, R.M.; Grethlein, A.J.; Soni, B.; Zeikus, J.G.; Grethlein, H.

    1990-05-07

    The project on biotechnology of indirect liquefaction was focused on conversion of coal derived synthesis gas to liquid fuels using a two-stage, acidogenic and solventogenic, anaerobic bioconversion process. The acidogenic fermentation used a novel and versatile organism, Butyribacterium methylotrophicum, which was fully capable of using CO as the sole carbon and energy source for organic acid production. In extended batch CO fermentations the organism was induced to produce butyrate at the expense of acetate at low pH values. Long-term, steady-state operation was achieved during continuous CO fermentations with this organism, and at low pH values (a pH of 6.0 or less) minor amounts of butanol and ethanol were produced. During continuous, steady-state fermentations of CO with cell recycle, concentrations of mixed acids and alcohols were achieved (approximately 12 g/l and 2 g/l, respectively) which are high enough for efficient conversion in stage two of the indirect liquefaction process. The metabolic pathway to produce 4-carbon alcohols from CO was a novel discovery and is believed to be unique to our CO strain of B. methylotrophicum. In the solventogenic phase, the parent strain ATCC 4259 of Clostridium acetobutylicum was mutagenized using nitrosoguanidine and ethyl methane sulfonate. The E-604 mutant strain of Clostridium acetobutylicum showed improved characteristics as compared to parent strain ATCC 4259 in batch fermentation of carbohydrates.

  18. TG16 point target detection experiment POLLEX, Livorno 2001

    NASA Astrophysics Data System (ADS)

    de Jong, Arie N.; Winkel, Hans; Moerman, Marcel M.; Stein, Karin; Weiss-Wrana, Karin; Forand, J. Luc; Potvin, Guy; Buss, James R.; Cini, Andrea; Vogel, Henrik H.; Stark, Espen

    2003-01-01

    NATO Task group TG16 is cooperating on topics related to ship self-defence. One of these topics is related to IR Search and Track sensors, which are in development for detection of low altitude air targets. In particular the group is working on models to predict the range performance of these sensors. Newly developed models include marine boundary layer effects such as refraction due to temperature gradients, scintillation due to turbulence and particle size distributions. TG16 organized in May 2001a trial in the Mediterranean Sea near Livorno, Italy, called POLLEX to further validate these models. Seven nations particulated with complementary instruments for measurements of the target signatures and environmental characteristics. Three targets were provided, a series of small visual/IR sources at a fixed distance, visual/IR soruces on a ship moving in and out up-to and beyond the horizon and a helicopter. The weather conditions during the measurement period showed interesting variations in Air to Sea Temperature DIfference and atmospheric turbulence. Data have been analzyed and samples of the results, as collected and/or analyzed by the participants, are discussed in this paper.

  19. Bayesian Validation of the Indirect Immunofluorescence Assay and Its Superiority to the Enzyme-Linked Immunosorbent Assay and the Complement Fixation Test for Detecting Antibodies against Coxiella burnetii in Goat Serum

    PubMed Central

    Stenos, John; Vincent, Gemma; Campbell, Angus; Graves, Stephen; Warner, Simone; Devlin, Joanne M.; Nguyen, Chelsea; Stevenson, Mark A.; Wilks, Colin R.; Firestone, Simon M.

    2016-01-01

    Although many studies have reported the indirect immunofluorescence assay (IFA) to be more sensitive in detection of antibodies to Coxiella burnetii than the complement fixation test (CFT), the diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the assay have not been previously established for use in ruminants. This study aimed to validate the IFA by describing the optimization, selection of cutoff titers, repeatability, and reliability as well as the DSe and DSp of the assay. Bayesian latent class analysis was used to estimate diagnostic specifications in comparison with the CFT and the enzyme-linked immunosorbent assay (ELISA). The optimal cutoff dilution for screening for IgG and IgM antibodies in goat serum using the IFA was estimated to be 1:160. The IFA had good repeatability (>96.9% for IgG, >78.0% for IgM), and there was almost perfect agreement (Cohen's kappa > 0.80 for IgG) between the readings reported by two technicians for samples tested for IgG antibodies. The IFA had a higher DSe (94.8%; 95% confidence interval [CI], 80.3, 99.6) for the detection of IgG antibodies against C. burnetii than the ELISA (70.1%; 95% CI, 52.7, 91.0) and the CFT (29.8%; 95% CI, 17.0, 44.8). All three tests were highly specific for goat IgG antibodies. The IFA also had a higher DSe (88.8%; 95% CI, 58.2, 99.5) for detection of IgM antibodies than the ELISA (71.7%; 95% CI, 46.3, 92.8). These results underscore the better suitability of the IFA than of the CFT and ELISA for detection of IgG and IgM antibodies in goat serum and possibly in serum from other ruminants. PMID:27122484

  20. Development of an indirect ELISA method based on the VP3 protein of duck hepatitis A virus type 1 (DHAV-1) for dual detection of DHAV-1 and DHAV-3 antibodies.

    PubMed

    Shen, Youlin; Cheng, Anchun; Wang, Mingshu; Chen, Shun; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Sun, Kunfeng; Yang, Qiao; Chen, Xiaoyue

    2015-12-01

    An indirect enzyme-linked immunosorbent assay (I-ELISA) based on the recombinant VP3 protein of duck hepatitis A virus type 1 (DHAV-1) was developed and evaluated in this study. The optimal antigen, serum and enzyme-labeled antibody dilutions were 1:160 (0.94μg), 1:160 and 1:2000, respectively. The optimal blocking buffer was 1% gelatin. The cutoff value was determined to be 0.332, and the analytical sensitivity was 1:1280 (OD450-630=0.37). The results of the specificity evaluation showed that no cross-reactivity existed between DHAV-1 antiserum and other common duck-sensitive pathogens, except for duck hepatitis A virus type 3 (DHAV-3), suggesting that this could be a common approach for the simultaneous detection of DHAV-1 and DHAV-3 antibodies. The coefficients of variation (CVs) for all of the tested samples were lower than 10%. The concordance between the I-ELISA based on the VP3 subunit of DHAV-1 and that based on the whole DHAV-1 particle was 96%. These results indicate that the VP3-based I-ELISA method has high sensitivity, specificity, and repeatability and is as effective as the DHAV-1-based I-ELISA method for sero-surveillance. Thus, it may be a convenient and novel method for DHAV antibody detection and epidemiological surveillance of DHAV prevalence.

  1. Sensitivity Enhancement in Multiple-Quantum NMR Experiments with CPMG Detection

    NASA Astrophysics Data System (ADS)

    Lim, Kwang Hun; Nguyen, Tuan; Mazur, Tanya; Wemmer, David E.; Pines, Alexander

    2002-07-01

    We present a modified multiple-quantum (MQ) experiment, which implements the Carr-Purcell-Meiboom-Gill (CPMG) detection scheme in the static MQ NMR experiment proposed by W. S. Warren et al. (1980, J. Chem. Phys.73, 2084-2099) and exploited further by O. N. Antzutkin and R. Tycko (1999, J. Chem. Phys.110, 2749-2752). It is demonstrated that a significant enhancement in the sensitivity can be achieved by acquiring echo trains in the MQ experiments for static powder samples. The modified scheme employing the CPMG detection was superior to the original MQ experiment, in particular for the carbonyl carbon with a very large chemical shift anisotropy.

  2. Structural chromosomal anomalies detected by prenatal genetic diagnosis: our experience.

    PubMed

    Farcaş, Simona; Crişan, C D; Andreescu, Nicoleta; Stoian, Monica; Motoc, A G M

    2013-01-01

    The prenatal diagnosis is currently widely spread and facilitates the acquiring of important genetic information about the fetus by a rate extremely accelerate and considered without precedent. In this paper, we like to present our experience concerning the genetic diagnosis and counseling offered for pregnancies in which a structural chromosomal aberration was found. The study group is formed by 528 prenatal samples of amniotic fluid and chorionic villi, received by our laboratory from 2006 through October 2012 for cytogenetic diagnosis. The appropriate genetic investigation was selected based on the indications for prenatal diagnosis. The cases with structural chromosomal anomalies and polymorphic variants were analyzed as regard to the maternal age, gestational age, referral indications and type of chromosomal anomaly found. A total number of 21 structural chromosomal anomalies and polymorphic variants were identified in the study group. Out of 21 structural chromosomal anomalies and polymorphic variants, six deletions and microdeletions, four situations with abnormal long "p" arm of acrocentric chromosomes, two duplications, two reciprocal translocations, two inversions, two additions, one Robertsonian translocation associating trisomy 13, one 9q heteromorphism and one complex chromosome rearrangement were noticed. To the best of our knowledge, this is the first Romanian study in which the diagnostic strategies and the management of the prenatal cases with structural rearrangements are presented. The data provided about the diagnosis strategy and the management of the prenatal cases with structural chromosomal anomalies represents a useful tool in genetic counseling of pregnancies diagnosed with rare structural chromosomal anomalies.

  3. Sensory Ecology of Water Detection by Bats: A Field Experiment

    PubMed Central

    Russo, Danilo; Cistrone, Luca; Jones, Gareth

    2012-01-01

    Bats face a great risk of dehydration, so sensory mechanisms for water recognition are crucial for their survival. In the laboratory, bats recognized any smooth horizontal surface as water because these provide analogous reflections of echolocation calls. We tested whether bats also approach smooth horizontal surfaces other than water to drink in nature by partly covering watering troughs used by hundreds of bats with a Perspex layer mimicking water. We aimed 1) to confirm that under natural conditions too bats mistake any horizontal smooth surface for water by testing this on large numbers of individuals from a range of species and 2) to assess the occurrence of learning effects. Eleven bat species mistook Perspex for water relying chiefly on echoacoustic information. Using black instead of transparent Perspex did not deter bats from attempting to drink. In Barbastella barbastellus no echolocation differences occurred between bats approaching the water and the Perspex surfaces respectively, confirming that bats perceive water and Perspex to be acoustically similar. The drinking attempt rates at the fake surface were often lower than those recorded in the laboratory: bats then either left the site or moved to the control water surface. This suggests that bats modified their behaviour as soon as the lack of drinking reward had overridden the influence of echoacoustic information. Regardless of which of two adjoining surfaces was covered, bats preferentially approached and attempted to drink from the first surface encountered, probably because they followed a common route, involving spatial memory and perhaps social coordination. Overall, although acoustic recognition itself is stereotyped and its importance in the drinking process overwhelming, our findings point at the role of experience in increasing behavioural flexibility under natural conditions. PMID:23133558

  4. Detection of Ocean Reflected GPS Signals: Theory and Experiment

    NASA Technical Reports Server (NTRS)

    Garrison, James L.; Katzberg, Stephen J.; Howell, Charles T., III

    1997-01-01

    A number of advanced applications of the Global Positioning System (GPS) have been proposed which use the signal reflected from a smooth ocean surface. The viability of these concepts hinges upon the ability to acquire and code track the reflected signal for an extended period of time over a variety of sea states. The analytical theory of specularly and diffusely reflected radio frequency radiation from a rough surface is reviewed. Experiments to demonstrate tracking of a reflected signal were performed on three aircraft flights over the Chesapeake Bay and the Eastern Shore of Virginia. The experimental hardware consisted of two of-the-shelf receivers configured so that one received the GPS signal in the conventional manner using a right hand circularly polarized (RHCP) antenna on top of the fuselage and the other could receive the reflected signal using a left hand circularly polarized (LHCP) antenna on the bottom of the fuselage. Three tests were performed on the data to verify that the signals received in the bottom antenna were viewed as sea surface reflections; Pseudorange double differences were compared against predicted geometric range double differences; Characteristics of a signal reflected from a random surface were observed in the carrier to noise ratio; Predicted specular points were plotted which demonstrate reflection only from wet areas. These tests indicated tracking of reflected signals for extended periods of time at altitudes of up to 5500 m and sporadic signal acquisition at higher altitudes. The duration of the continuous signal tracking was limited by the receiver's need to maintain carrier tracking.

  5. Sensory ecology of water detection by bats: a field experiment.

    PubMed

    Russo, Danilo; Cistrone, Luca; Jones, Gareth

    2012-01-01

    Bats face a great risk of dehydration, so sensory mechanisms for water recognition are crucial for their survival. In the laboratory, bats recognized any smooth horizontal surface as water because these provide analogous reflections of echolocation calls. We tested whether bats also approach smooth horizontal surfaces other than water to drink in nature by partly covering watering troughs used by hundreds of bats with a Perspex layer mimicking water. We aimed 1) to confirm that under natural conditions too bats mistake any horizontal smooth surface for water by testing this on large numbers of individuals from a range of species and 2) to assess the occurrence of learning effects. Eleven bat species mistook Perspex for water relying chiefly on echoacoustic information. Using black instead of transparent Perspex did not deter bats from attempting to drink. In Barbastella barbastellus no echolocation differences occurred between bats approaching the water and the Perspex surfaces respectively, confirming that bats perceive water and Perspex to be acoustically similar. The drinking attempt rates at the fake surface were often lower than those recorded in the laboratory: bats then either left the site or moved to the control water surface. This suggests that bats modified their behaviour as soon as the lack of drinking reward had overridden the influence of echoacoustic information. Regardless of which of two adjoining surfaces was covered, bats preferentially approached and attempted to drink from the first surface encountered, probably because they followed a common route, involving spatial memory and perhaps social coordination. Overall, although acoustic recognition itself is stereotyped and its importance in the drinking process overwhelming, our findings point at the role of experience in increasing behavioural flexibility under natural conditions.

  6. Towards a Bullet-proof test for indirect signals of dark matter

    NASA Astrophysics Data System (ADS)

    Graham, Peter W.; Rajendran, Surjeet; Van Tilburg, Ken; Wiser, Timothy D.

    2015-05-01

    Merging galaxy clusters such as the Bullet Cluster provide a powerful testing ground for indirect detection of dark matter. The spatial distribution of the dark matter is both directly measurable through gravitational lensing and substantially different from the distribution of potential astrophysical backgrounds. We propose to use this spatial information to identify the origin of indirect detection signals, and we show that even statistical excesses of a few sigma can be robustly tested for consistency—or inconsistency—with a dark matter source. For example, our methods, combined with already-existing observations of the Coma Cluster, would allow the 3.55 keV line to be tested for compatibility with a dark matter origin. We also discuss the optimal spatial reweighting of photons for indirect detection searches. The current discovery rate of merging galaxy clusters and associated lensing maps strongly motivates deep exposures in these dark matter targets for both current and upcoming indirect detection experiments in the x-ray and gamma-ray bands.

  7. Future Dust Detection Experiments on Japanese Space Missions

    NASA Astrophysics Data System (ADS)

    Sasaki, S.; Ohashi, H.; Nogami, K.; Iglseder, H.; Fujiwara, A.; Yano, H.; Mukai, T.; Ishimoto, H.; Yamamoto, S.; Kobayashi, K.; Shibata, H.

    1996-09-01

    Direct measurements of dust particle in space have unveiled characteristics of interplanetary and interstellar dust particles. In addition to the approved PLANET-B MDC (Mars Dust Counter) in 1998, two dust detectors with mass spectrometry are proposed for Japanese future space missions: lunar and asteroid missions. A lunar orbiter mission is planned by NASDA (National Space Development Agency of Japan) and ISAS (The Institute of Space and Astronautical Science). The mission, which has also a relay satellite and a test lander, will be launched in 2003 by H-II vehicle. The orbiter is three-axis stabilized satellite that has both lunar and anti-lunar direction platforms. We propose two dust analyzers involving mass spectrometry using impact ionization: one on the lunar side will measure dust flux from the moon and the other on the anti-lunar side will measure interplanetary and interstellar particles. Each dust analyzer which has an axisymmetric ion mirror is 4.3kg in weight and 240x275x357 mm(3) in shape with 38000mm(2) aperture area. We aim at chemical analysis (with mass resolution m/dm >= 300) of dust particles as small as 1 micron. MUSES-C is an asteroid sample return mission which is managed by ISAS. It will be launched in late 2001 by M-V, will arrive at asteroid Nereus in 2004 and return back to the Earth with surface samples in 2006. In addition to the sampler, several scientific instruments are proposed to be on board MUSES-C. We propose an impact ionization dust detector with a simple ion mirror for mass spectrometry. The detector is 1.0kg in weight and 180x125x275 mm(3) in shape. The main purpose is to measure time and spatial variations of interplanetary and interstellar dust particles and to investigate if dust particles are enhanced at Nereus orbit. To detect relatively low velocity particles around Nereus, we also propose to have a piezo film detector on the satellite surface.

  8. Dark Matter Indirect Detection with Gamma Rays

    DOE PAGES

    Patrick Harding, J.

    2017-07-27

    Searches for weakly interacting massive particle (WIMP) dark matter with gamma-ray instruments are a way to get a unique observational handle on the particle nature of dark matter. I will discuss the details of how to perform these searches, both for annihilating and decaying WIMPs. I will discuss the calculation of the gamma-ray flux from possible sources of dark matter annihilation or decay and show examples of limits which have been calculated using these techniques.

  9. Theoretical Synthesis of Indirect Detection Results

    NASA Astrophysics Data System (ADS)

    Profumo, Stefano

    2015-04-01

    Can we learn about New Physics with astronomical and astro-particle data? Understanding how this is possible is key to unraveling one of the most pressing mysteries at the interface of cosmology and particle physics: the fundamental, particle-physics nature of dark matter. I will discuss some of the recent puzzling findings in astro-particle and astronomical observations that might be related to signals from dark matter. I will first review the status of explanations to the cosmic-ray positron excess, emphasizing how we might be able to discriminate between astrophysical sources and dark matter. I will then discuss the evidence for an X-ray line at 3.5 keV, and present new results on systematic effects and on the role of previously underestimated astrophysical lines. Finally, I will briefly discuss a reported excess of gamma rays from the central regions of the Galaxy.

  10. A Two-Week Guided Inquiry Protein Separation and Detection Experiment for Undergraduate Biochemistry

    ERIC Educational Resources Information Center

    Carolan, James P.; Nolta, Kathleen V.

    2016-01-01

    A laboratory experiment for teaching protein separation and detection in an undergraduate biochemistry laboratory course is described. This experiment, performed in two, 4 h laboratory periods, incorporates guided inquiry principles to introduce students to the concepts behind and difficulties of protein purification. After using size-exclusion…

  11. A Two-Week Guided Inquiry Protein Separation and Detection Experiment for Undergraduate Biochemistry

    ERIC Educational Resources Information Center

    Carolan, James P.; Nolta, Kathleen V.

    2016-01-01

    A laboratory experiment for teaching protein separation and detection in an undergraduate biochemistry laboratory course is described. This experiment, performed in two, 4 h laboratory periods, incorporates guided inquiry principles to introduce students to the concepts behind and difficulties of protein purification. After using size-exclusion…

  12. Surprise, p-value, s-value and a diagnostic procedure to detect not informative experiments

    NASA Astrophysics Data System (ADS)

    Recchia, Daniela R.; Ostermann, Thomas; Garcia, Jesus E.

    2016-06-01

    In this paper, examples of diverse measures of significance are studied in the frame of Neyman-Pearson hypothesis tests. A diagnostic procedure is proposed, to detect non informative experiments where the p-value procedure might fail to measure the significance of the outcome of an experiment.

  13. [Value of functional lymphoscintigraphy and indirect lymphangiography in lipedema syndrome].

    PubMed

    Weissleder, H; Brauer, J W; Schuchhardt, C; Herpertz, U

    1995-12-01

    Early terms of lymphostasis in lipedema can be detected with lymphoscintigraphy. A normal examination almost certainly excludes a lymphatic component. Indirect lymphography is only used to rule out morphological abnormalities of lymph vessels. If a lymphoscintigraphic study is normal indirect lymphography is not indicated.

  14. Integration of experiments for the detection of biological activity in extraterrestrial exploration

    NASA Technical Reports Server (NTRS)

    Merek, E. L.; Oyama, V. I.

    1970-01-01

    Although many experiments have been suggested and described for the detection of biological activity in planetary exploration, each experiment has required its own sample for the detection of a specific phenomenon. An experimental design which could detect growth, catabolic and anabolic activity on a single sample is described. Growth is monitored in a liquid medium which is in contact with, and chemically influenced by, a relatively large sample. Catabolic activity is indicated by changes in the gas composition of the atmosphere above the sample. Anabolic activity is indicated by the appearance of reduced carbon compounds, from oxidized precursors, in the liquid medium.

  15. Bose-Einstein condensation and indirect excitons: a review

    NASA Astrophysics Data System (ADS)

    Combescot, Monique; Combescot, Roland; Dubin, François

    2017-06-01

    We review recent progress on Bose-Einstein condensation (BEC) of semiconductor excitons. The first part deals with theory, the second part with experiments. This Review is written at a time where the problem of exciton Bose-Einstein condensation has just been revived by the understanding that the exciton condensate must be dark because the exciton ground state is not coupled to light. Here, we theoretically discuss this missed understanding before providing its experimental support through experiments that scrutinize indirect excitons made of spatially separated electrons and holes. The theoretical part first discusses condensation of elementary bosons. In particular, the necessary inhibition of condensate fragmentation by exchange interaction is stressed, before extending the discussion to interacting bosons with spin degrees of freedom. The theoretical part then considers composite bosons made of two fermions like semiconductor excitons. The spin structure of the excitons is detailed, with emphasis on the crucial fact that ground-state excitons are dark: indeed, this imposes the exciton Bose-Einstein condensate to be not coupled to light in the dilute regime. Condensate fragmentations are then reconsidered. In particular, it is shown that while at low density, the exciton condensate is fully dark, it acquires a bright component, coherent with the dark one, beyond a density threshold: in this regime, the exciton condensate is ‘gray’. The experimental part first discusses optical creation of indirect excitons in quantum wells, and the detection of their photoluminescence. Exciton thermalisation is also addressed, as well as available approaches to estimate the exciton density. We then switch to specific experiments where indirect excitons form a macroscopic fragmented ring. We show that such ring provides efficient electrostatic trapping in the region of the fragments where an essentially-dark exciton Bose-Einstein condensate is formed at sub-Kelvin bath

  16. Bose-Einstein condensation and indirect excitons: a review.

    PubMed

    Combescot, Monique; Combescot, Roland; Dubin, François

    2017-06-01

    We review recent progress on Bose-Einstein condensation (BEC) of semiconductor excitons. The first part deals with theory, the second part with experiments. This Review is written at a time where the problem of exciton Bose-Einstein condensation has just been revived by the understanding that the exciton condensate must be dark because the exciton ground state is not coupled to light. Here, we theoretically discuss this missed understanding before providing its experimental support through experiments that scrutinize indirect excitons made of spatially separated electrons and holes. The theoretical part first discusses condensation of elementary bosons. In particular, the necessary inhibition of condensate fragmentation by exchange interaction is stressed, before extending the discussion to interacting bosons with spin degrees of freedom. The theoretical part then considers composite bosons made of two fermions like semiconductor excitons. The spin structure of the excitons is detailed, with emphasis on the crucial fact that ground-state excitons are dark: indeed, this imposes the exciton Bose-Einstein condensate to be not coupled to light in the dilute regime. Condensate fragmentations are then reconsidered. In particular, it is shown that while at low density, the exciton condensate is fully dark, it acquires a bright component, coherent with the dark one, beyond a density threshold: in this regime, the exciton condensate is 'gray'. The experimental part first discusses optical creation of indirect excitons in quantum wells, and the detection of their photoluminescence. Exciton thermalisation is also addressed, as well as available approaches to estimate the exciton density. We then switch to specific experiments where indirect excitons form a macroscopic fragmented ring. We show that such ring provides efficient electrostatic trapping in the region of the fragments where an essentially-dark exciton Bose-Einstein condensate is formed at sub-Kelvin bath

  17. Determination of aminopolycarboxylic acids at ultra-trace levels by means of online coupling ion exchange chromatography and inductively coupled plasma-mass spectrometry with indirect detection via their Pd²⁺-complexes.

    PubMed

    Nette, David; Seubert, Andreas

    2015-07-16

    A new indirect IC-ICP-MS method for the determination of aminopolycarboxylic acids in water samples is described. It is based on the addition of an excess of Pd(II) to water samples. The analytes are forced into very strong and negatively charged palladium complexes, separated by ion exchange chromatography and detected by their palladium content, utilizing an on-line coupled ICP-MS. This method is suitable to determine the concentration of 8 aminopolycarboxylic acids (nitrilotriacetic acid (NTA), (2-carboxyethyl) iminodiacetic acid (β-ADA), methylglycinediacetic acid (MGDA), 2-hydroxyethyl) ethylenediamine triacetic acid (HEDTA), diethylene triamine pentaacetic acid (DTPA), ethylendiamine tetraacetic acid (EDTA), 1,3-diaminopropane tetraacetic acid (1,3-PDTA) and 1,2-diaminopropane tetraacetic acid (1,2-PDTA) at the ng kg(-1) level. The method is faster and easier than the established gas chromatography (GC)-method ISO 16588:2002 and up to two orders of magnitude more sensitive than the ion pair chromatography based method of DIN 38413-8. Analytic performance is superior to ISO 16588:2002 and the comparability is good. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Developing a discrete choice experiment in Malawi: eliciting preferences for breast cancer early detection services.

    PubMed

    Kohler, Racquel E; Lee, Clara N; Gopal, Satish; Reeve, Bryce B; Weiner, Bryan J; Wheeler, Stephanie B

    2015-01-01

    In Malawi, routine breast cancer screening is not available and little is known about women's preferences regarding early detection services. Discrete choice experiments are increasingly used to reveal preferences about new health services; however, selecting appropriate attributes that describe a new health service is imperative to ensure validity of the choice experiment. To identify important factors that are relevant to Malawian women's preferences for breast cancer detection services and to select attributes and levels for a discrete choice experiment in a setting where both breast cancer early detection and choice experiments are rare. We reviewed the literature to establish an initial list of potential attributes and levels for a discrete choice experiment and conducted qualitative interviews with health workers and community women to explore relevant local factors affecting decisions to use cancer detection services. We tested the design through cognitive interviews and refined the levels, descriptions, and designs. Themes that emerged from interviews provided critical information about breast cancer detection services, specifically, that breast cancer interventions should be integrated into other health services because asymptomatic screening may not be practical as an individual service. Based on participants' responses, the final attributes of the choice experiment included travel time, health encounter, health worker type and sex, and breast cancer early detection strategy. Cognitive testing confirmed the acceptability of the final attributes, comprehension of choice tasks, and women's abilities to make trade-offs. Applying a discrete choice experiment for breast cancer early detection was feasible with appropriate tailoring for a low-income, low-literacy African setting.

  19. Physical examination of arteriovenous fistula: The influence of professional experience in the detection of complications.

    PubMed

    Sousa, Clemente Neves; Teles, Paulo; Dias, Vanessa Filipa Ferreira; Apóstolo, João Luís Alves; Figueiredo, Maria Henriqueta Jesus Silva; Martins, Maria Manuela

    2014-07-01

    Vascular access is one of the leading causes of mobilization of financial resources in health systems for people with chronic kidney disease on hemodialysis. Physical examination of the arteriovenous fistula (AVF) has demonstrated its effectiveness in identifying complications. We decided to evaluate the influence of nurses' professional experience in the detection of complications of the AVF (venous stenosis and steal syndrome). The study took place in eight hemodialysis centers between May and September of 2011 in the north of Portugal. Sample was constituted by registered nurses. The nurses involved in the experiment were divided in two groups: those who had more than 5 years of experience and those who had less than 5 years of experience. Ninety-two nurses participated in the study: 34 nurses had less than 5 years of professional experience and 58 had more than 5 years of professional experience. In the practices considered by nurses in the detection of venous stenosis, there were no differences observed between the groups (P > 0.05). In steal syndrome, there were no differences observed between the groups in the practices of the nurses in the detection of this complication of the AVF (P > 0.05). We concluded that professional experience does not influence the detection of venous stenosis and steal syndrome. © 2014 International Society for Hemodialysis.

  20. Indirect combustion noise of auxiliary power units

    NASA Astrophysics Data System (ADS)

    Tam, Christopher K. W.; Parrish, Sarah A.; Xu, Jun; Schuster, Bill

    2013-08-01

    Recent advances in noise suppression technology have significantly reduced jet and fan noise from commercial jet engines. This leads many investigators in the aeroacoustics community to suggest that core noise could well be the next aircraft noise barrier. Core noise consists of turbine noise and combustion noise. There is direct combustion noise generated by the combustion processes, and there is indirect combustion noise generated by the passage of combustion hot spots, or entropy waves, through constrictions in an engine. The present work focuses on indirect combustion noise. Indirect combustion noise has now been found in laboratory experiments. The primary objective of this work is to investigate whether indirect combustion noise is also generated in jet and other engines. In a jet engine, there are numerous noise sources. This makes the identification of indirect combustion noise a formidable task. Here, our effort concentrates exclusively on auxiliary power units (APUs). This choice is motivated by the fact that APUs are relatively simple engines with only a few noise sources. It is, therefore, expected that the chance of success is higher. Accordingly, a theoretical model study of the generation of indirect combustion noise in an Auxiliary Power Unit (APU) is carried out. The cross-sectional areas of an APU from the combustor to the turbine exit are scaled off to form an equivalent nozzle. A principal function of a turbine in an APU is to extract mechanical energy from the flow stream through the exertion of a resistive force. Therefore, the turbine is modeled by adding a negative body force to the momentum equation. This model is used to predict the ranges of frequencies over which there is a high probability for indirect combustion noise generation. Experimental spectra of internal pressure fluctuations and far-field noise of an RE220 APU are examined to identify anomalous peaks. These peaks are possible indirection combustion noise. In the case of the

  1. Direct and indirect punishment among strangers in the field

    PubMed Central

    Balafoutas, Loukas; Nikiforakis, Nikos; Rockenbach, Bettina

    2014-01-01

    Many interactions in modern human societies are among strangers. Explaining cooperation in such interactions is challenging. The two most prominent explanations critically depend on individuals’ willingness to punish defectors: In models of direct punishment, individuals punish antisocial behavior at a personal cost, whereas in models of indirect reciprocity, they punish indirectly by withholding rewards. We investigate these competing explanations in a field experiment with real-life interactions among strangers. We find clear evidence of both direct and indirect punishment. Direct punishment is not rewarded by strangers and, in line with models of indirect reciprocity, is crowded out by indirect punishment opportunities. The existence of direct and indirect punishment in daily life indicates the importance of both means for understanding the evolution of cooperation. PMID:25349390

  2. Direct and indirect punishment among strangers in the field.

    PubMed

    Balafoutas, Loukas; Nikiforakis, Nikos; Rockenbach, Bettina

    2014-11-11

    Many interactions in modern human societies are among strangers. Explaining cooperation in such interactions is challenging. The two most prominent explanations critically depend on individuals' willingness to punish defectors: In models of direct punishment, individuals punish antisocial behavior at a personal cost, whereas in models of indirect reciprocity, they punish indirectly by withholding rewards. We investigate these competing explanations in a field experiment with real-life interactions among strangers. We find clear evidence of both direct and indirect punishment. Direct punishment is not rewarded by strangers and, in line with models of indirect reciprocity, is crowded out by indirect punishment opportunities. The existence of direct and indirect punishment in daily life indicates the importance of both means for understanding the evolution of cooperation.

  3. Ablative Richtmyer-Meshkov instability with indirect drive

    NASA Astrophysics Data System (ADS)

    Velikovich, A. L.; Clark, D. S.; Smalyuk, V. A.; Landen, O. L.; Mikaelian, K. O.; Robey, H. F.; Wouchuk, J. G.

    2016-10-01

    Ablative Richtmyer-Meshkov (ARM) instability develops while a strong radiation pulse, rapidly rising to its constant peak intensity, drives a constant-strength shock wave from the rippled irradiated surface of a solid target into its volume. For the direct laser irradiation, the theory, experiment, and simulations have demonstrated that the development of the ARM results in decaying oscillations of the areal mass/optical thickness modulation amplitude. Much less is known about the ARM with the indirect drive. This effect causing oscillations of the ablation front is the physical basis of the recently proposed and successfully demonstrated adiabat-shaping approach to improving the NIF target performance. We report a theoretical and numerical stability analysis of the indirectly-driven shock-piston flow performed to investigate the physical mechanism of the ablation-front oscillations detected in the simulations and the NIF experiments on adiabat shaping. This work was performed under the auspices of the US DOE/NNSA by NRL, and by LLNL under contract DE-AC52-07NA27344. JGW was supported by MINECO under Grant No. ENE2013-45661-C2-1-P, and JCCM, PEI-2014-008.

  4. Propellant Feed System Leak Detection: Lessons Learned From the Linear Aerospike SR-71 Experiment (LASRE)

    NASA Technical Reports Server (NTRS)

    Hass, Neal; Mizukami, Masashi; Neal, Bradford A.; St. John, Clinton; Beil, Robert J.; Griffin, Timothy P.

    1999-01-01

    This paper presents pertinent results and assessment of propellant feed system leak detection as applied to the Linear Aerospike SR-71 Experiment (LASRE) program flown at the NASA Dryden Flight Research Center, Edwards, California. The LASRE was a flight test of an aerospike rocket engine using liquid oxygen and high-pressure gaseous hydrogen as propellants. The flight safety of the crew and the experiment demanded proven technologies and techniques that could detect leaks and assess the integrity of hazardous propellant feed systems. Point source detection and systematic detection were used. Point source detection was adequate for catching gross leakage from components of the propellant feed systems, but insufficient for clearing LASRE to levels of acceptability. Systematic detection, which used high-resolution instrumentation to evaluate the health of the system within a closed volume, provided a better means for assessing leak hazards. Oxygen sensors detected a leak rate of approximately 0.04 cubic inches per second of liquid oxygen. Pressure sensor data revealed speculated cryogenic boiloff through the fittings of the oxygen system, but location of the source(s) was indeterminable. Ultimately, LASRE was cancelled because leak detection techniques were unable to verify that oxygen levels could be maintained below flammability limits.

  5. The neutrino burst from SN 1987A detected in the Mont Blanc LSD experiment.

    NASA Astrophysics Data System (ADS)

    Aglietta, M.; Badino, G.; Bologna, G.; Castagnoli, C.; Castellina, A.; Dadykin, V. L.; Fulgione, W.; Galeotti, P.; Kalchukov, F. F.; Khalchukov, F. F.; Kortchaguin, V. B.; Korchagin, V. B.; Kortchaguin, P. V.; Korchagin, P. V.; Malguin, A. S.; Mal'Gin, A. S.; Ryassny, V. G.; Ryasnyj, V. G.; Ryazhkaya, O. G.; Saavedra, O.; Talochkin, V. P.; Trinchero, G.; Vernetto, S.; Zatsepin, G. T.; Yakushev, V. F.

    The authors discuss the event, (5 interactions recorded during 7 seconds) detected in the Mont Blanc Underground Neutrino Observatory on February 23, 1987, during the occurrence of supernova SN 1987A. The pulse amplitudes, the background imitation probability, and the energetics connected with the event are reported. It is also shown that some interactions recorded at the same time in other underground experiments, with a lower detection efficiency, are consistent with the Mont Blanc event.

  6. GHz modulation detection using a streak camera: Suitability of streak cameras in the AWAKE experiment

    NASA Astrophysics Data System (ADS)

    Rieger, K.; Caldwell, A.; Reimann, O.; Muggli, P.

    2017-02-01

    Using frequency mixing, a modulated light pulse of ns duration is created. We show that, with a ps-resolution streak camera that is usually used for single short pulse measurements, we can detect via an FFT detection approach up to 450 GHz modulation in a pulse in a single measurement. This work is performed in the context of the AWAKE plasma wakefield experiment where modulation frequencies in the range of 80-280 GHz are expected.

  7. Directed Design of Experiments (DOE) for Determining Probability of Detection (POD) Capability of NDE Systems (DOEPOD)

    NASA Technical Reports Server (NTRS)

    Generazio, Ed

    2007-01-01

    This viewgraph presentation reviews some of the issues that people who specialize in Non destructive evaluation (NDE) have with determining the statistics of the probability of detection. There is discussion of the use of the binominal distribution, and the probability of hit. The presentation then reviews the concepts of Directed Design of Experiments for Validating Probability of Detection of Inspection Systems (DOEPOD). Several cases are reviewed, and discussed. The concept of false calls is also reviewed.

  8. Off-line experiments on radionuclide detection based on the sequential Bayesian approach

    NASA Astrophysics Data System (ADS)

    Qingpei, Xiang; Dongfeng, Tian; Fanhua, Hao; Ge, Ding; Jun, Zeng; Fei, Luo

    2013-11-01

    The sequential Bayesian approach proposed by Candy et al. for radioactive materials detection has aroused increasing interest in radiation detection research and is potentially a useful tool for prevention of the transportation of radioactive materials by terrorists. In our previous work, the performance of the sequential Bayesian approach was studied numerically through a simulation experiment platform. In this paper, a sequential Bayesian processor incorporating a LaBr3(Ce) detector, and using the energy, decay rate and emission probability of the radionuclide, is fully developed. Off-line experiments for the performance of the sequential Bayesian approach in radionuclide detection are developed by placing 60Co, 137Cs, 133Ba and 152Eu at various distances from the front face of the LaBr3(Ce) detector. The off-line experiment results agree well with the results of previous numerical experiments. The maximum detection distance is introduced to evaluate the processor‧s ability to detect radionuclides with a specific level of activity.

  9. WE-G-204-05: Relative Object Detectability Evaluation of a New High Resolution A-Se Direct Detection System Compared to Indirect Micro-Angiographic Fluoroscopic (MAF) Detectors

    SciTech Connect

    Russ, M; Nagesh, S Setlur; Ionita, C; Bednarek, D; Rudin, S; Scott, C; Karim, K

    2015-06-15

    Purpose: To evaluate the task specific imaging performance of a new 25µm pixel pitch, 1000µm thick amorphous selenium direct detection system with CMOS readout for typical angiographic exposure parameters using the relative object detectability (ROD) metric. Methods: The ROD metric uses a simulated object function weighted at each spatial frequency by the detectors’ detective quantum efficiency (DQE), which is an intrinsic performance metric. For this study, the simulated objects were aluminum spheres of varying diameter (0.05–0.6mm). The weighted object function is then integrated over the full range of detectable frequencies inherent to each detector, and a ratio is taken of the resulting value for two detectors. The DQE for the 25µm detector was obtained from a simulation of a proposed a-Se detector using an exposure of 200µR for a 50keV x-ray beam. This a-Se detector was compared to two microangiographic fluoroscope (MAF) detectors [the MAF-CCD with pixel size of 35µm and Nyquist frequency of 14.2 cycles/mm and the MAF-CMOS with pixel size of 75µm and Nyquist frequency of 6.6 cycles/mm] and a standard flat-panel detector (FPD with pixel size of 194µm and Nyquist frequency of 2.5cycles/mm). Results: ROD calculations indicated vastly superior performance by the a-Se detector in imaging small aluminum spheres. For the 50µm diameter sphere, the ROD values for the a-Se detector compared to the MAF-CCD, the MAF-CMOS, and the FPD were 7.3, 9.3 and 58, respectively. Detector performance in the low frequency regime was dictated by each detector’s DQE(0) value. Conclusion: The a-Se with CMOS readout is unique and appears to have distinctive advantages of incomparable high resolution, low noise, no readout lag, and expandable design. The a-Se direct detection system will be a powerful imaging tool in angiography, with potential break-through applications in diagnosis and treatment of neuro-vascular disease. Supported by NIH Grant: 2R01EB002873 and an

  10. A storage ring experiment to detect a proton electric dipole moment

    NASA Astrophysics Data System (ADS)

    Anastassopoulos, V.; Andrianov, S.; Baartman, R.; Baessler, S.; Bai, M.; Benante, J.; Berz, M.; Blaskiewicz, M.; Bowcock, T.; Brown, K.; Casey, B.; Conte, M.; Crnkovic, J. D.; D'Imperio, N.; Fanourakis, G.; Fedotov, A.; Fierlinger, P.; Fischer, W.; Gaisser, M. O.; Giomataris, Y.; Grosse-Perdekamp, M.; Guidoboni, G.; Hacıömeroǧlu, S.; Hoffstaetter, G.; Huang, H.; Incagli, M.; Ivanov, A.; Kawall, D.; Kim, Y. I.; King, B.; Koop, I. A.; Lazarus, D. M.; Lebedev, V.; Lee, M. J.; Lee, S.; Lee, Y. H.; Lehrach, A.; Lenisa, P.; Levi Sandri, P.; Luccio, A. U.; Lyapin, A.; MacKay, W.; Maier, R.; Makino, K.; Malitsky, N.; Marciano, W. J.; Meng, W.; Meot, F.; Metodiev, E. M.; Miceli, L.; Moricciani, D.; Morse, W. M.; Nagaitsev, S.; Nayak, S. K.; Orlov, Y. F.; Ozben, C. S.; Park, S. T.; Pesce, A.; Petrakou, E.; Pile, P.; Podobedov, B.; Polychronakos, V.; Pretz, J.; Ptitsyn, V.; Ramberg, E.; Raparia, D.; Rathmann, F.; Rescia, S.; Roser, T.; Kamal Sayed, H.; Semertzidis, Y. K.; Senichev, Y.; Sidorin, A.; Silenko, A.; Simos, N.; Stahl, A.; Stephenson, E. J.; Ströher, H.; Syphers, M. J.; Talman, J.; Talman, R. M.; Tishchenko, V.; Touramanis, C.; Tsoupas, N.; Venanzoni, G.; Vetter, K.; Vlassis, S.; Won, E.; Zavattini, G.; Zelenski, A.; Zioutas, K.

    2016-11-01

    A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of 10-29 e ṡ cm by using polarized "magic" momentum 0.7 GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the standard model at the scale of 3000 TeV.

  11. A storage ring experiment to detect a proton electric dipole moment

    DOE PAGES

    Anastassopoulos, V.; Andrianov, S.; Baartman, R.; ...

    2016-11-29

    We describe a new experiment to detect a permanent electric dipole moment of the proton with a sensitivity of 10$-$29e cm by using polarized “magic” momentum 0.7 GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the Standard Model at the scale of 3000 TeV.

  12. A storage ring experiment to detect a proton electric dipole moment

    SciTech Connect

    Anastassopoulos, V.; Andrianov, S.; Baartman, R.; Baessler, S.; Bai, M.; Benante, J.; Berz, M.; Blaskiewicz, M.; Bowcock, T.; Brown, K.; Casey, B.; Conte, M.; Crnkovic, J. D.; D’Imperio, N.; Fanourakis, G.; Fedotov, A.; Fierlinger, P.; Fischer, W.; Gaisser, M. O.; Giomataris, Y.; Guidoboni, G.; Hacıömeroğlu, S.; Hoffstaetter, G.; Huang, H.; Incagli, M.; Ivanov, A.; Kawall, D.; Kim, Y. I.; King, B.; Koop, I. A.; Lazarus, D. M.; Lebedev, V.; Lee, M. J.; Lee, S.; Lee, Y. H.; Lehrach, A.; Lenisa, P.; Levi Sandri, P.; Luccio, A. U.; Lyapin, A.; MacKay, W.; Maier, R.; Makino, K.; Malitsky, N.; Marciano, W. J.; Meng, W.; Meot, F.; Metodiev, E. M.; Miceli, L.; Moricciani, D.; Morse, W. M.; Nagaitsev, S.; Nayak, S. K.; Orlov, Y. F.; Ozben, C. S.; Park, S. T.; Pesce, A.; Petrakou, E.; Pile, P.; Podobedov, B.; Polychronakos, V.; Pretz, J.; Ptitsyn, V.; Ramberg, E.; Raparia, D.; Rathmann, F.; Rescia, S.; Roser, T.; Kamal Sayed, H.; Semertzidis, Y. K.; Senichev, Y.; Sidorin, A.; Silenko, A.; Simos, N.; Stahl, A.; Stephenson, E. J.; Ströher, H.; Syphers, M. J.; Talman, J.; Talman, R. M.; Tishchenko, V.; Touramanis, C.; Tsoupas, N.; Venanzoni, G.; Vetter, K.; Vlassis, S.; Won, E.; Zavattini, G.; Zelenski, A.; Zioutas, K.

    2016-11-29

    We describe a new experiment to detect a permanent electric dipole moment of the proton with a sensitivity of 10$-$29e cm by using polarized “magic” momentum 0.7 GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the Standard Model at the scale of 3000 TeV.

  13. A storage ring experiment to detect a proton electric dipole moment.

    PubMed

    Anastassopoulos, V; Andrianov, S; Baartman, R; Baessler, S; Bai, M; Benante, J; Berz, M; Blaskiewicz, M; Bowcock, T; Brown, K; Casey, B; Conte, M; Crnkovic, J D; D'Imperio, N; Fanourakis, G; Fedotov, A; Fierlinger, P; Fischer, W; Gaisser, M O; Giomataris, Y; Grosse-Perdekamp, M; Guidoboni, G; Hacıömeroğlu, S; Hoffstaetter, G; Huang, H; Incagli, M; Ivanov, A; Kawall, D; Kim, Y I; King, B; Koop, I A; Lazarus, D M; Lebedev, V; Lee, M J; Lee, S; Lee, Y H; Lehrach, A; Lenisa, P; Levi Sandri, P; Luccio, A U; Lyapin, A; MacKay, W; Maier, R; Makino, K; Malitsky, N; Marciano, W J; Meng, W; Meot, F; Metodiev, E M; Miceli, L; Moricciani, D; Morse, W M; Nagaitsev, S; Nayak, S K; Orlov, Y F; Ozben, C S; Park, S T; Pesce, A; Petrakou, E; Pile, P; Podobedov, B; Polychronakos, V; Pretz, J; Ptitsyn, V; Ramberg, E; Raparia, D; Rathmann, F; Rescia, S; Roser, T; Kamal Sayed, H; Semertzidis, Y K; Senichev, Y; Sidorin, A; Silenko, A; Simos, N; Stahl, A; Stephenson, E J; Ströher, H; Syphers, M J; Talman, J; Talman, R M; Tishchenko, V; Touramanis, C; Tsoupas, N; Venanzoni, G; Vetter, K; Vlassis, S; Won, E; Zavattini, G; Zelenski, A; Zioutas, K

    2016-11-01

    A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of 10(-29) e ⋅ cm by using polarized "magic" momentum 0.7 GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the standard model at the scale of 3000 TeV.

  14. Poker face of inelastic dark matter: Prospects at upcoming direct detection experiments

    NASA Astrophysics Data System (ADS)

    Alves, Daniele S. M.; Lisanti, Mariangela; Wacker, Jay G.

    2010-08-01

    The XENON100 and CRESST experiments will directly test the inelastic dark matter explanation for DAMA’s 8.9σ anomaly. This article discusses how predictions for direct detection experiments depend on uncertainties in quenching factor measurements, the dark matter interaction with the standard model, and the halo velocity distribution. When these uncertainties are accounted for, an order of magnitude variation is found in the number of expected events at CRESST and XENON100.

  15. A storage ring experiment to detect a proton electric dipole moment

    SciTech Connect

    Anastassopoulos, V.; Andrianov, S.; Baartman, R.; Baessler, S.; Bai, M.; Benante, J.; Berz, M.; Blaskiewicz, M.; Bowcock, T.; Brown, K.; Casey, B.; Conte, M.; Crnkovic, J. D.; D’Imperio, N.; Fanourakis, G.; Fedotov, A.; Fierlinger, P.; Fischer, W.; Gaisser, M. O.; Giomataris, Y.; Guidoboni, G.; Hacıömeroğlu, S.; Hoffstaetter, G.; Huang, H.; Incagli, M.; Ivanov, A.; Kawall, D.; Kim, Y. I.; King, B.; Koop, I. A.; Lazarus, D. M.; Lebedev, V.; Lee, M. J.; Lee, S.; Lee, Y. H.; Lehrach, A.; Lenisa, P.; Levi Sandri, P.; Luccio, A. U.; Lyapin, A.; MacKay, W.; Maier, R.; Makino, K.; Malitsky, N.; Marciano, W. J.; Meng, W.; Meot, F.; Metodiev, E. M.; Miceli, L.; Moricciani, D.; Morse, W. M.; Nagaitsev, S.; Nayak, S. K.; Orlov, Y. F.; Ozben, C. S.; Park, S. T.; Pesce, A.; Petrakou, E.; Pile, P.; Podobedov, B.; Polychronakos, V.; Pretz, J.; Ptitsyn, V.; Ramberg, E.; Raparia, D.; Rathmann, F.; Rescia, S.; Roser, T.; Kamal Sayed, H.; Semertzidis, Y. K.; Senichev, Y.; Sidorin, A.; Silenko, A.; Simos, N.; Stahl, A.; Stephenson, E. J.; Ströher, H.; Syphers, M. J.; Talman, J.; Talman, R. M.; Tishchenko, V.; Touramanis, C.; Tsoupas, N.; Venanzoni, G.; Vetter, K.; Vlassis, S.; Won, E.; Zavattini, G.; Zelenski, A.; Zioutas, K.

    2016-11-01

    A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of $10^{-29}e\\cdot$cm by using polarized "magic" momentum $0.7$~GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the Standard Model at the scale of 3000~TeV.

  16. Development of competitive indirect ELISA for the detection of tetrodotoxin and a survey of the distribution of tetrodotoxin in the tissues of wild puffer fish in the waters of south-east China.

    PubMed

    Tao, J; Wei, W J; Nan, L; Lei, L H; Hui, H C; Fen, G X; Jun, L Y; Jing, Z; Rong, J

    2010-11-01

    A monoclonal antibody against tetrodotoxin (TTX) was produced from the hybridoma cell line T6D9, which was established by the fusion of Sp2/0 myeloma cells with spleen cells isolated from a Balb/c mouse immunized with the TTX-keyhole limpet hemocyanin (KLH) conjugate. This monoclonal antibody belongs to the IgG1 subclass; the affinity constant of the antibody is 2.4 × 10(-8) mol l(-1). The relative cross-reactivity of the antibody with TTX was 100%, but with saxitoxin, KLH and bovine serum albumin (BSA) it was less than 1%, respectively. The titre of the antibody in ascites was 6.4 × 10(6); the reference working concentration was 1:1.2 × 10(5). By using this monoclonal antibody, a competitive indirect enzyme-linked immunoabsorbant assay (ELISA) for the analysis of TTX was developed. The linear portion of the dose-response curve of TTX concentration was in range 5-500 ng ml(-1). The limit of detection was 5 ng ml(-1) according 10% inhibition with TTX to anti-TTX monoclonal antibody. The concentration of TTX inhibiting 50% of antibody binding was about 50 ng ml(-1). The recoveries from TTX spiked samples were 79.5-109.5%. In addition, the toxicity of some wild puffer fish specimens captured from south-east China and the Yangzi River in Jiangsu province was determined. The results indicate that the toxicity and toxin tissue distribution vary in different species of wild puffer fish.

  17. Avalanches in a granular stick-slip experiment: detection using wavelets

    NASA Astrophysics Data System (ADS)

    Abed Zadeh, Aghil; Barés, Jonathan; Behringer, Robert P.

    2017-06-01

    Avalanches have been experimentally investigated in a wide range of physical systems from granular physics to friction. Here, we measure and detect avalanches in a 2D granular stick-slip experiment. We discuss the conventional way of signal processing for avalanche extraction and how statistics depend on several parameters that are chosen in the analysis process. Then, we introduce another way of detecting avalanches using wavelet transformations that can be applied in many other systems. We show that by using this method and measuring Lipschitz exponents, we can intelligently detect noise in a signal, which leads to a better avalanche extraction and more reliable avalanche statistics.

  18. The ArDM, a ton-scale liquid argon experiment for direct dark matter detection

    NASA Astrophysics Data System (ADS)

    Otyugova, P.; Ar DM Collaboration

    2008-07-01

    The ArDM project aims at developing and operating large noble liquid detectors to search for direct evidence of Weakly Interacting Massive Particles (WIMP) as Dark Matter in the Universe. The initial goal is to design, assemble and operate an approximately 1 ton liquid argon prototype based on the double-phase detection principle to demonstrate the feasibility of a ton-scale experiment with the required performance to efficiently detect and sufficiently discriminate backgrounds for a successful WIMP detection. The detector will independently measure the primary scintillation light and the ionization charge. This paper will mainly describe the concept, R&D results and status of the charge read out system.

  19. Analyses and experiments of background sunlight's effects on laser detection system

    NASA Astrophysics Data System (ADS)

    Guo, Hao; Yin, Rui-guang; Ma, Na; Liang, Wei-wei; Li, Bo

    2015-10-01

    Background sunlight effect the technical performance of laser detection system significantly. Analyses and experiments were done to find the degree and regularity of effects of background sunlight on laser detection system. At first, we established the theoretical model of laser detection probability curve. We emulated and analysed the effects on probability curve under different sunlight intensity by the model. Moreover, we got the variation regularity of parameter in probability curve. Secondly, we proposed a prediction method of probability curve, which deduced the detecting parameter from measured data. The method can not only get the probability curve in arbitrary background sunlight by a measured probability curve in typical background sunlight, but also calculate the sensitivity of laser detection systems by probability curve at the specified probability. Thirdly, we measured the probability curves under three types of background sunlight. The illumination conditions in experiments included fine, overcast and night. These three curves can be used as reference to deduce other curves. Using model, method, and measured data mentioned above, we finally finished the analyses and appraisal of the effects of background sunlight on typical laser detection system. The research findings can provide the theoretical reference and technical support for adaptability evaluation of typical laser detection systems in different background sunlight.

  20. Interplay and characterization of Dark Matter searches at colliders and in direct detection experiments

    DOE PAGES

    Malik, Sarah A.; McCabe, Christopher; Araujo, Henrique; ...

    2015-05-18

    In our White Paper we present and discuss a concrete proposal for the consistent interpretation of Dark Matter searches at colliders and in direct detection experiments. Furthermore, based on a specific implementation of simplified models of vector and axial-vector mediator exchanges, this proposal demonstrates how the two search strategies can be compared on an equal footing.

  1. Noble Gas Migration Experiment to Support the Detection of Underground Nuclear Explosions

    SciTech Connect

    Olsen, Khris B.; Kirkham, Randy R.; Woods, Vincent T.; Haas, Derek A.; Hayes, James C.; Bowyer, Ted W.; Mendoza, Donaldo P.; Lowrey, Justin D.; Lukins, Craig D.; Suarez, Reynold; Humble, Paul H.; Ellefson, Mark D.; Ripplinger, Mike D.; Zhong, Lirong; Mitroshkov, Alexandre V.; Aalseth, Craig E.; Prinke, Amanda M.; Mace, Emily K.; McIntyre, Justin I.; Stewart, Timothy L.; Mackley, Rob D.; Milbrath, Brian D.; Emer, Dudley; Biegalski, S.

    2016-03-01

    A Noble Gas Migration Experiment (NGME) funded by the National Center for Nuclear Security and conducted at the Nevada National Security Site (NNSS) in collaboration with Lawrence Livermore national Laboratory and National Security Technology provided critical on-site inspection (OSI) information related to the detection of an underground nuclear explosion (UNE) event using noble gas signatures.

  2. Interplanetary and near-Jupiter meteoroid environments - Preliminary results from the meteoroid detection experiment

    NASA Technical Reports Server (NTRS)

    Kinard, W. H.; O'Neal, R. L.; Alvarez, J. M.; Humes, D. H.

    1974-01-01

    Data on interplanetary and near-Jupiter micrometer-sized particle encounters from the meteoroid-detection experiment on Pioneer 10 indicate that Jupiter is much 'dustier' than interplanetary space. Whereas the near-earth particulate flux showed very little increase over the interplanetary flux, the near-Jupiter penetration flux was over two orders of magnitude higher than the interplanetary flux.

  3. An EAS experiment at mountain altitude for the detection of gamma-ray sources

    NASA Technical Reports Server (NTRS)

    Allkofer, O. C.; Samorski, M.; Stamm, W.

    1985-01-01

    The plan of an extensive air shower experiment 2.200 m above sea level for the detection of 10 to the 14th power eV to 10 to the 17th power eV gamma rays from sources in the declination band 0 deg to + 60 deg is described. The site selection, detector array and electronic layout are detailed.

  4. Increasing sensitivity of pulse EPR experiments using echo train detection schemes

    NASA Astrophysics Data System (ADS)

    Mentink-Vigier, F.; Collauto, A.; Feintuch, A.; Kaminker, I.; Tarle, V.; Goldfarb, D.

    2013-11-01

    Modern pulse EPR experiments are routinely used to study the structural features of paramagnetic centers. They are usually performed at low temperatures, where relaxation times are long and polarization is high, to achieve a sufficient Signal/Noise Ratio (SNR). However, when working with samples whose amount and/or concentration are limited, sensitivity becomes an issue and therefore measurements may require a significant accumulation time, up to 12 h or more. As the detection scheme of practically all pulse EPR sequences is based on the integration of a spin echo - either primary, stimulated or refocused - a considerable increase in SNR can be obtained by replacing the single echo detection scheme by a train of echoes. All these echoes, generated by Carr-Purcell type sequences, are integrated and summed together to improve the SNR. This scheme is commonly used in NMR and here we demonstrate its applicability to a number of frequently used pulse EPR experiments: Echo-Detected EPR, Davies and Mims ENDOR (Electron-Nuclear Double Resonance), DEER (Electron-Electron Double Resonance|) and EDNMR (Electron-Electron Double Resonance (ELDOR)-Detected NMR), which were combined with a Carr-Purcell-Meiboom-Gill (CPMG) type detection scheme at W-band. By collecting the transient signal and integrating a number of refocused echoes, this detection scheme yielded a 1.6-5 folds SNR improvement, depending on the paramagnetic center and the pulse sequence applied. This improvement is achieved while keeping the experimental time constant and it does not introduce signal distortion.

  5. Prospects for cosmic neutrino detection in tritium experiments in the case of hierarchical neutrino masses

    SciTech Connect

    Blennow, Mattias

    2008-06-01

    We discuss the effects of neutrino mixing and the neutrino mass hierarchy when considering the capture of the cosmic neutrino background (CNB) on radioactive nuclei. The implications of mixing and hierarchy at future generations of tritium decay experiments are considered. We find that the CNB should be detectable at these experiments provided that the resolution for the kinetic energy of the outgoing electron can be pushed to a few 0.01 eV for the scenario with inverted neutrino mass hierarchy, about an order of magnitude better than that of the upcoming KATRIN experiment. Another order of magnitude improvement is needed in the case of normal neutrino mass hierarchy. We also note that mixing effects generally make the prospects for CNB detection worse due to an increased maximum energy of the normal beta decay background.

  6. Direct vs. Indirect Moral Enhancement.

    PubMed

    Schaefer, G Owen

    2015-09-01

    Moral enhancement is an ostensibly laudable project. Who wouldn't want people to become more moral? Still, the project's approach is crucial. We can distinguish between two approaches for moral enhancement: direct and indirect. Direct moral enhancements aim at bringing about particular ideas, motives or behaviors. Indirect moral enhancements, by contrast, aim at making people more reliably produce the morally correct ideas, motives or behaviors without committing to the content of those ideas, motives and/or actions. I will argue, on Millian grounds, that the value of disagreement puts serious pressure on proposals for relatively widespread direct moral enhancement. A more acceptable path would be to focus instead on indirect moral enhancements while staying neutral, for the most part, on a wide range of substantive moral claims. I will outline what such indirect moral enhancement might look like, and why we should expect it to lead to general moral improvement.

  7. Detection system for neutron β decay correlations in the UCNB and Nab experiments

    NASA Astrophysics Data System (ADS)

    Broussard, L. J.; Zeck, B. A.; Adamek, E. R.; Baeßler, S.; Birge, N.; Blatnik, M.; Bowman, J. D.; Brandt, A. E.; Brown, M.; Burkhart, J.; Callahan, N. B.; Clayton, S. M.; Crawford, C.; Cude-Woods, C.; Currie, S.; Dees, E. B.; Ding, X.; Fomin, N.; Frlez, E.; Fry, J.; Gray, F. E.; Hasan, S.; Hickerson, K. P.; Hoagland, J.; Holley, A. T.; Ito, T. M.; Klein, A.; Li, H.; Liu, C.-Y.; Makela, M. F.; McGaughey, P. L.; Mirabal-Martinez, J.; Morris, C. L.; Ortiz, J. D.; Pattie, R. W.; Penttilä, S. I.; Plaster, B.; Počanić, D.; Ramsey, J. C.; Salas-Bacci, A.; Salvat, D. J.; Saunders, A.; Seestrom, S. J.; Sjue, S. K. L.; Sprow, A. P.; Tang, Z.; Vogelaar, R. B.; Vorndick, B.; Wang, Z.; Wei, W.; Wexler, J.; Wilburn, W. S.; Womack, T. L.; Young, A. R.

    2017-03-01

    We describe a detection system designed for precise measurements of angular correlations in neutron β decay. The system is based on thick, large area, highly segmented silicon detectors developed in collaboration with Micron Semiconductor, Ltd. The prototype system meets specifications for β electron detection with energy thresholds below 10 keV, energy resolution of ∼3 keV FWHM, and rise time of ∼50 ns with 19 of the 127 detector pixels instrumented. Using ultracold neutrons at the Los Alamos Neutron Science Center, we have demonstrated the coincident detection of β particles and recoil protons from neutron β decay. The fully instrumented detection system will be implemented in the UCNB and Nab experiments to determine the neutron β decay parameters B, a, and b.

  8. The logic of indirect speech

    PubMed Central

    Pinker, Steven; Nowak, Martin A.; Lee, James J.

    2008-01-01

    When people speak, they often insinuate their intent indirectly rather than stating it as a bald proposition. Examples include sexual come-ons, veiled threats, polite requests, and concealed bribes. We propose a three-part theory of indirect speech, based on the idea that human communication involves a mixture of cooperation and conflict. First, indirect requests allow for plausible deniability, in which a cooperative listener can accept the request, but an uncooperative one cannot react adversarially to it. This intuition is supported by a game-theoretic model that predicts the costs and benefits to a speaker of direct and indirect requests. Second, language has two functions: to convey information and to negotiate the type of relationship holding between speaker and hearer (in particular, dominance, communality, or reciprocity). The emotional costs of a mismatch in the assumed relationship type can create a need for plausible deniability and, thereby, select for indirectness even when there are no tangible costs. Third, people perceive language as a digital medium, which allows a sentence to generate common knowledge, to propagate a message with high fidelity, and to serve as a reference point in coordination games. This feature makes an indirect request qualitatively different from a direct one even when the speaker and listener can infer each other's intentions with high confidence. PMID:18199841

  9. The relationship study between image features and detection probability based on psychology experiments

    NASA Astrophysics Data System (ADS)

    Lin, Wei; Chen, Yu-hua; Wang, Ji-yuan; Gao, Hong-sheng; Wang, Ji-jun; Su, Rong-hua; Mao, Wei

    2011-04-01

    Detection probability is an important index to represent and estimate target viability, which provides basis for target recognition and decision-making. But it will expend a mass of time and manpower to obtain detection probability in reality. At the same time, due to the different interpretation of personnel practice knowledge and experience, a great difference will often exist in the datum obtained. By means of studying the relationship between image features and perception quantity based on psychology experiments, the probability model has been established, in which the process is as following.Firstly, four image features have been extracted and quantified, which affect directly detection. Four feature similarity degrees between target and background were defined. Secondly, the relationship between single image feature similarity degree and perception quantity was set up based on psychological principle, and psychological experiments of target interpretation were designed which includes about five hundred people for interpretation and two hundred images. In order to reduce image features correlativity, a lot of artificial synthesis images have been made which include images with single brightness feature difference, images with single chromaticity feature difference, images with single texture feature difference and images with single shape feature difference. By analyzing and fitting a mass of experiments datum, the model quantitys have been determined. Finally, by applying statistical decision theory and experimental results, the relationship between perception quantity with target detection probability has been found. With the verification of a great deal of target interpretation in practice, the target detection probability can be obtained by the model quickly and objectively.

  10. Optimizing detection of RDX vapors using designed experiments for remote sensing.

    PubMed

    Ewing, Robert G; Heredia-Langner, Alejandro; Warner, Marvin G

    2014-05-21

    This paper presents results of designed experiments performed to study the effect of four factors on the detection of RDX vapors from desorption into an atmospheric flow tube mass spectrometer (AFT-MS). The experiments initially included four independent factors: gas flow rate, desorption current, solvent evaporation time and RDX mass. The values of three detection responses, peak height, peak width, and peak area were recorded but only the peak height response was analyzed. Results from the first block of experiments indicated that solvent evaporation time was not statistically significant at the 95% confidence level. A second round of experiments was designed and executed using flow rate, current, and RDX mass as factors and the results were used to create a model to predict conditions resulting in maximum peak height. Those conditions were confirmed experimentally and used to obtain data for a calibration model. The calibration model represented RDX amounts ranging from 1 to 25 pg desorbed into an air flow of 7 L min(-1). Air samples from a shipping container that held 2 closed explosive storage magazines were collected on metal filaments for varying amounts for time ranging from 5 to 90 minutes. RDX was detected from all of the filaments sampled by desorption into the AFT-MS. From the calibration model, RDX vapor concentrations within the shipping container were calculated to be in the range of 1 to 50 parts-per-quadrillion (ppqv) from data collected on 2 separate days.

  11. Optimizing detection of RDX vapors using designed experiments for remote sensing

    SciTech Connect

    Ewing, Robert G.; Heredia-Langner, Alejandro; Warner, Marvin G.

    2014-03-24

    Abstract: This paper presents results of experiments performed to study the effect of four factors on the detection of RDX vapors from desorption into an atmospheric flow tube mass spectrometer (AFT-MS). The experiments initially included four independent factors: gas flow rate, desorption current, solvent evaporation time and RDX mass. The values of three detection responses, peak height, peak width, and peak area were recorded but only the peak height response was analyzed. Results from the first block of experiments indicated that solvent evaporation time was not statistically significant. A second round of experiments was performed using flow rate, current, and RDX mass as factors and the results were used to create a model to predict conditions resulting in maximum peak height. Those conditions were confirmed experimentally and used to obtain data for a calibration model. The calibration model represented RDX amounts ranging from 1 to 25 pg desorbed into an air flow of 7 L/min. Air samples from a shipping container that held 2 closed explosive storage magazines were collected on metal filaments for varying amounts for time ranging from 5 to 90 minutes. RDX was detected from all of the filaments sampled by desorption into the AFT-MS. From the calibration model, RDX vapor concentrations within the shipping container were calculated to be in the range of 1 to 50 parts-per-quadrillion from data collected on 2 separate days.

  12. The Dynamical Response of Dark Matter to Galaxy Evolution Affects Direct-Detection Experiments

    NASA Astrophysics Data System (ADS)

    Petersen, Michael; Katz, Neal; Weinberg, Martin

    2017-01-01

    Over a handful of rotation periods, dynamical processes in barred galaxies induce non-axisymmetric structure in dark matter halos. Using n-body simulations of a Milky Way-like barred galaxy, we identify both a trapped dark-matter component, a shadow bar, and a strong response wake in the dark-matter distribution that affects the predicted dark-matter detection rates for current and future experiments. We find that the magnitude of the combined stellar and shadow bar evolution makes a 30% increase in disk-plane density. This is significantly larger that of previously claimed deviations from the standard halo model. The dark-matter density and kinematic wakes driven by the Milky Way bar increase the detectability of dark matter overall, especially for the experiments with higher minimum velocities. These astrophysical features increase the detection rate by more than a factor of two when compared to the standard halo model and by a factor of ten for experiments with high minimum recoil energy thresholds. These same features increase (decrease) the annual modulation for low (high) minimum recoil energy experiments. We present physical arguments for why these dynamics are generic for barred galaxies such as the Milky Way rather than contingent on a specific galaxy model.

  13. Characterising dark matter searches at colliders and direct detection experiments: Vector mediators

    DOE PAGES

    Buchmueller, Oliver; Dolan, Matthew J.; Malik, Sarah A.; ...

    2015-01-09

    We introduce a Minimal Simplified Dark Matter (MSDM) framework to quantitatively characterise dark matter (DM) searches at the LHC. We study two MSDM models where the DM is a Dirac fermion which interacts with a vector and axial-vector mediator. The models are characterised by four parameters: mDM, Mmed , gDM and gq, the DM and mediator masses, and the mediator couplings to DM and quarks respectively. The MSDM models accurately capture the full event kinematics, and the dependence on all masses and couplings can be systematically studied. The interpretation of mono-jet searches in this framework can be used to establishmore » an equal-footing comparison with direct detection experiments. For theories with a vector mediator, LHC mono-jet searches possess better sensitivity than direct detection searches for light DM masses (≲5 GeV). For axial-vector mediators, LHC and direct detection searches generally probe orthogonal directions in the parameter space. We explore the projected limits of these searches from the ultimate reach of the LHC and multi-ton xenon direct detection experiments, and find that the complementarity of the searches remains. In conclusion, we provide a comparison of limits in the MSDM and effective field theory (EFT) frameworks to highlight the deficiencies of the EFT framework, particularly when exploring the complementarity of mono-jet and direct detection searches.« less

  14. Characterising dark matter searches at colliders and direct detection experiments: Vector mediators

    SciTech Connect

    Buchmueller, Oliver; Dolan, Matthew J.; Malik, Sarah A.; McCabe, Christopher

    2015-01-09

    We introduce a Minimal Simplified Dark Matter (MSDM) framework to quantitatively characterise dark matter (DM) searches at the LHC. We study two MSDM models where the DM is a Dirac fermion which interacts with a vector and axial-vector mediator. The models are characterised by four parameters: mDM, Mmed , gDM and gq, the DM and mediator masses, and the mediator couplings to DM and quarks respectively. The MSDM models accurately capture the full event kinematics, and the dependence on all masses and couplings can be systematically studied. The interpretation of mono-jet searches in this framework can be used to establish an equal-footing comparison with direct detection experiments. For theories with a vector mediator, LHC mono-jet searches possess better sensitivity than direct detection searches for light DM masses (≲5 GeV). For axial-vector mediators, LHC and direct detection searches generally probe orthogonal directions in the parameter space. We explore the projected limits of these searches from the ultimate reach of the LHC and multi-ton xenon direct detection experiments, and find that the complementarity of the searches remains. In conclusion, we provide a comparison of limits in the MSDM and effective field theory (EFT) frameworks to highlight the deficiencies of the EFT framework, particularly when exploring the complementarity of mono-jet and direct detection searches.

  15. Description of the meteoroid detection experiment flown on the Pioneer 10 and 11 Jupiter flyby missions

    NASA Technical Reports Server (NTRS)

    Oneal, R. L. (Compiler)

    1974-01-01

    The meteoroid detection experiment has the objective of measuring the population of 10 to the minus 9th power and 10 to the minus 8th power grams mass particles in interplanetary space with emphasis on making these measurements in the Asteroid Belt. The instrument design, which uses the pressurized-cell-penetration detection technique, and the tests involved in obtaining a flight-qualified instrument are described. The successful demonstration of flight-quality penetration detectors to function properly under long-term simulated space environments is also described.

  16. Research and design of the electronics system for the underground dark matter detection experiment in IHEP

    NASA Astrophysics Data System (ADS)

    Jun, H.; Xiaoshan, J.; Jie, Z.; Wei, W.; Gang, L.

    2015-03-01

    The underground dark matter experiment in IHEP searches for direct detection of dark matter using CsI(Na) as detector material. Rare nuclear recoil events of dark matter particles scattering off the target material will be detected by photomultiplier tubes (PMTs). This paper describes the electronics system structure we chose for this detector. It focuses on the design of the main modules, the high-speed ADC module and the 2-level data acquisition module. Some performance results are presented at the end.

  17. Neutrino detection systematics in the two detector phase of the Double Chooz experiment

    NASA Astrophysics Data System (ADS)

    Almazan, H.; Navas-Nicolás, D.

    2017-09-01

    Being an intense and pure source of low energy electron antineutrinos, nuclear reactors are one of the most powerful tools to investigate neutrino oscillations. The Double Chooz experiment aims for a precise determination of the neutrino mixing angle θ 13 using a two detector configuration with a liquid scintillator target volume read by photomultipliers. The antineutrino detection efficiency systematic uncertainty is the dominant component in the normalization uncertainty affecting the final precision on the θ 13 measurement.The collected data from the near detector since January 2015 will profit from improved detection systematic uncertainties thanks to the cancellation of correlated contributions between both detectors.

  18. Do cyclists make better drivers? Associations between cycling experience and change detection in road scenes.

    PubMed

    Beanland, Vanessa; Hansen, Lisa J

    2017-07-18

    Efficient processing of visual information is crucial to safe driving. Previous research has demonstrated that driving experience strongly affects attentional allocation, with large differences between novice and experienced drivers. Expanding on this, we explored the influence of non-driving experiences on attentional allocation by comparing drivers with and without cycling experience. Based on situation awareness field studies, we predicted cyclist-drivers would demonstrate superior performance. Participants were 42 experienced drivers (17 female, 25 male) aged 30-50 years (M=39.8): 20 drivers and 22 cyclist-drivers. The experiment used a change detection flicker task, in which participants must determine whether two alternating images are identical (change-absent) or differ in a single detail (change-present). The changed object was either a road sign, car, pedestrian, or bicycle. Change target significantly affected both accuracy and response time: all participants were slower and less accurate at detecting changes to road signs, compared with when the change was a moving road user (i.e., car, pedestrian, bicycle). Accuracy did not differ significantly between groups, but cyclist-drivers were significantly faster than drivers at identifying changes, with the effect being largest for bicycle and sign changes. The results suggest that cycling experience is associated with more efficient attentional processing for road scenes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Indirect dark matter searches in gamma and cosmic rays

    NASA Astrophysics Data System (ADS)

    Conrad, Jan; Reimer, Olaf

    2017-03-01

    Dark matter candidates such as weakly interacting massive particles are predicted to annihilate or decay into Standard Model particles, leaving behind distinctive signatures in gamma rays, neutrinos, positrons, antiprotons, or even antinuclei. Indirect dark matter searches, and in particular those based on gamma-ray observations and cosmic-ray measurements, could detect such signatures. Here we review the strengths and limitations of this approach and look into the future of indirect dark matter searches.

  20. Neural Processing Associated with Comprehension of an Indirect Reply during a Scenario Reading Task

    ERIC Educational Resources Information Center

    Shibata, Midori; Abe, Jun-ichi; Itoh, Hiroaki; Shimada, Koji; Umeda, Satoshi

    2011-01-01

    In daily communication, we often use indirect speech to convey our intention. However, little is known about the brain mechanisms that underlie the comprehension of indirect speech. In this study, we conducted a functional MRI experiment using a scenario reading task to compare the neural activity induced by an indirect reply (a type of indirect…

  1. A Monte Carlo Simulation for Understanding Energy Measurements of Beta Particles Detected by the UCNb Experiment

    NASA Astrophysics Data System (ADS)

    Feng, Chi; UCNb Collaboration

    2011-10-01

    It is theorized that contributions to the Fierz interference term from scalar interaction beyond the Standard Model could be detectable in the spectrum of neutron beta-decay. The UCNb experiment run at the Los Alamos Neutron Science Center aims to accurately measure the neutron beta-decay energy spectrum to detect a nonzero interference term. The instrument consists of a cubic ``integrating sphere'' calorimeter attached with up to 4 photomultiplier tubes. The inside of the calorimeter is coated with white paint and a thin UV scintillating layer made of deuterated polystyrene to contain the ultracold neutrons. A Monte Carlo simulation using the Geant4 toolkit is developed in order to provide an accurate method of energy reconstruction. Offline calibration with the Kellogg Radiation Laboratory 140 keV electron gun and conversion electron sources will be used to validate the Monte Carlo simulation to give confidence in the energy reconstruction methods and to better understand systematics in the experiment data.

  2. Forecast constraints on inflation from combined CMB and gravitational wave direct detection experiments

    SciTech Connect

    Kuroyanagi, Sachiko; Gordon, Christopher; Silk, Joseph; Sugiyama, Naoshi

    2010-04-15

    We study how direct detection of the inflationary gravitational wave background constrains inflationary parameters and complements CMB polarization measurements. The error ellipsoids calculated using the Fisher information matrix approach with Planck and the direct detection experiment, Big Bang Observer (BBO), show different directions of parameter degeneracy, and the degeneracy is broken when they are combined. For a slow-roll parametrization, we show that BBO could significantly improve the constraints on the tensor-to-scalar ratio compared with Planck alone. We also look at a quadratic and a natural inflation model. In both cases, if the temperature of reheating is also treated as a free parameter, then the addition of BBO can significantly improve the error bars. In the case of natural inflation, we find that the addition of BBO could even partially improve the error bars of a cosmic variance-limited CMB experiment.

  3. Magnetoelastic Effect-Based Transmissive Stress Detection for Steel Strips: Theory and Experiment

    PubMed Central

    Zhang, Qingdong; Su, Yuanxiao; Zhang, Liyuan; Bi, Jia; Luo, Jiang

    2016-01-01

    For the deficiencies of traditional stress detection methods for steel strips in industrial production, this paper proposes a non-contact stress detection scheme based on the magnetoelastic effect. The theoretical model of the transmission-type stress detection is established, in which the output voltage and the tested stress obey a linear relation. Then, a stress detection device is built for the experiment, and Q235 steel under uniaxial tension is tested as an example. The result shows that the output voltage rises linearly with the increase of the tensile stress, consistent with the theoretical prediction. To ensure the accuracy of the stress detection method in actual application, the temperature compensation, magnetic shielding and some other key technologies are investigated to reduce the interference of the external factors, such as environment temperature and surrounding magnetic field. The present research develops the theoretical and experimental foundations for the magnetic stress detection system, which can be used for online non-contact monitoring of strip flatness-related stress (tension distribution or longitudinal residual stress) in the steel strip rolling process, the quality evaluation of strip flatness after rolling, the life and safety assessment of metal construction and other industrial production links. PMID:27589742

  4. Indirect Reciprocity under Incomplete Observation

    PubMed Central

    Nakamura, Mitsuhiro; Masuda, Naoki

    2011-01-01

    Indirect reciprocity, in which individuals help others with a good reputation but not those with a bad reputation, is a mechanism for cooperation in social dilemma situations when individuals do not repeatedly interact with the same partners. In a relatively large society where indirect reciprocity is relevant, individuals may not know each other's reputation even indirectly. Previous studies investigated the situations where individuals playing the game have to determine the action possibly without knowing others' reputations. Nevertheless, the possibility that observers of the game, who generate the reputation of the interacting players, assign reputations without complete information about them has been neglected. Because an individual acts as an interacting player and as an observer on different occasions if indirect reciprocity is endogenously sustained in a society, the incompleteness of information may affect either role. We examine the game of indirect reciprocity when the reputations of players are not necessarily known to observers and to interacting players. We find that the trustful discriminator, which cooperates with good and unknown players and defects against bad players, realizes cooperative societies under seven social norms. Among the seven social norms, three of the four suspicious norms under which cooperation (defection) to unknown players leads to a good (bad) reputation enable cooperation down to a relatively small observation probability. In contrast, the three trustful norms under which both cooperation and defection to unknown players lead to a good reputation are relatively efficient. PMID:21829335

  5. The Future of Indirect Evidence

    PubMed Central

    Efron, Bradley

    2009-01-01

    Familiar statistical tests and estimates are obtained by the direct observation of cases of interest: a clinical trial of a new drug, for instance, will compare the drug’s effects on a relevant set of patients and controls. Sometimes, though, indirect evidence may be temptingly available, perhaps the results of previous trials on closely related drugs. Very roughly speaking, the difference between direct and indirect statistical evidence marks the boundary between frequentist and Bayesian thinking. Twentieth-century statistical practice focused heavily on direct evidence, on the grounds of superior objectivity. Now, however, new scientific devices such as microarrays routinely produce enormous data sets involving thousands of related situations, where indirect evidence seems too important to ignore. Empirical Bayes methodology offers an attractive direct/indirect compromise. There is already some evidence of a shift toward a less rigid standard of statistical objectivity that allows better use of indirect evidence. This article is basically the text of a recent talk featuring some examples from current practice, with a little bit of futuristic speculation. PMID:21243111

  6. An Experiment for Simulated Detection of Earth-Size Planetary Transits

    NASA Astrophysics Data System (ADS)

    Koch, D.; Borucki, W.; Dunham, E.; Jenkins, J.; Witteborn, F.

    1999-05-01

    The concept for detection of Earth-size planets by looking for transits has been described by Borucki and Summers (1984). A space mission for detecting hundreds of Earth-size planets has been described by Koch, et al. (1998). The method depends on reliably detecting a relative change in brightness of order 8x10(-5) . Prior laboratory measurements have demonstrated this level of relative precision using CCDs (Robinson, et al., 1995, Jenkins, et al., 1997). A higher fidelity experiment is now being constructed to detect simulated Earth-size transits using a flight-type CCD. In addition, the experiment incorporates many of the major confounding factors which could affect the detection capability including: spacecraft jitter, a realistic star background, thermal changes, stellar variability, cosmic-ray hits, etc. Details of the experiment are presented including the method for producing the equivalent of earth-size transit signals. Borucki, W. J. and Summers, A.L., Icarus 58, 121 (1984) Jenkins, J. M., Borucki, W. J., Dunham, E. W. and McDonald, J. S., High Precision Photometry with Back-Illuminated CCDs, In Proceedings of the Planets Beyond Our Solar System and Next Generation Space Telescope, ASP Conf Ser ,119, 227-280 (1997) Koch, D., Borucki, W., Webster, L., Dunham, E. , Jenkins, J., Marriott, J. and Reitsema, H., SPIE 3356, Space Telescopes and Instruments V, 599-607, March (1998) Robinson, L. B, M. Z. Wei, W. J. Borucki, E.W. Dunham, C. H. Ford, and A. F. Granados. PASP 107, 1094-1098 (1995)

  7. The importance of study design for detecting differentially abundant features in high-throughput experiments.

    PubMed

    Luo, Huaien; Li, Juntao; Chia, Burton Kuan Hui; Robson, Paul; Nagarajan, Niranjan

    2014-12-03

    High-throughput assays, such as RNA-seq, to detect differential abundance are widely used. Variable performance across statistical tests, normalizations, and conditions leads to resource wastage and reduced sensitivity. EDDA represents a first, general design tool for RNA-seq, Nanostring, and metagenomic analysis, that rationally selects tests, predicts performance, and plans experiments to minimize resource wastage. Case studies highlight EDDA's ability to model single-cell RNA-seq, suggesting ways to reduce sequencing costs up to five-fold and improving metagenomic biomarker detection through improved test selection. EDDA's novel mode-based normalization for detecting differential abundance improves robustness by 10% to 20% and precision by up to 140%.

  8. Detection system for neutron β decay correlations in the UCNB and Nab experiments

    SciTech Connect

    Broussard, L. J.; Zeck, B. A.; Adamek, E. R.; Baeßler, S.; Birge, N.; Blatnik, M.; Bowman, J. D.; Brandt, A. E.; Brown, M.; Burkhart, J.; Callahan, N. B.; Clayton, S. M.; Crawford, C.; Cude-Woods, C.; Currie, S.; Dees, E. B.; Ding, X.; Fomin, N.; Frlez, E.; Fry, J.; Gray, F. E.; Hasan, S.; Hickerson, K. P.; Hoagland, J.; Holley, A. T.; Ito, T. M.; Klein, A.; Li, H.; Liu, C. -Y.; Makela, M. F.; McGaughey, P. L.; Mirabal-Martinez, J.; Morris, C. L.; Ortiz, J. D.; Pattie, R. W.; Penttilä, S. I.; Plaster, B.; Počanić, D.; Ramsey, J. C.; Salas-Bacci, A.; Salvat, D. J.; Saunders, A.; Seestrom, S. J.; Sjue, S. K. L.; Sprow, A. P.; Tang, Z.; Vogelaar, R. B.; Vorndick, B.; Wang, Z.; Wei, W.; Wexler, J.; Wilburn, W. S.; Womack, T. L.; Young, A. R.

    2016-12-19

    Here, we describe a detection system designed to precisely measure multiple correlations in neutron β decay. Furthermore, the system is based on thick, large area, highly segmented silicon detectors developed in collaboration with Micron Semiconductor, Ltd. The prototype system meets specifications of energy thresholds below 10 keV, energy resolution of ~3 keV FWHM, and rise time of ~50 ns with 19 of the 127 detector pixels instrumented. We have demonstrated the coincident detection of β particles and recoil protons from neutron β decay, using ultracold neutrons at the Los Alamos Neutron Science Center, . The fully instrumented detection system will be implemented in the UCNB and Nab experiments, to determine the neutron β decay parameters B, a, and b.

  9. Detection system for neutron β decay correlations in the UCNB and Nab experiments

    DOE PAGES

    Broussard, L. J.; Oak Ridge National Lab.; Zeck, B. A.; ...

    2016-12-19

    Here, we describe a detection system designed to precisely measure multiple correlations in neutron β decay. Furthermore, the system is based on thick, large area, highly segmented silicon detectors developed in collaboration with Micron Semiconductor, Ltd. The prototype system meets specifications of energy thresholds below 10 keV, energy resolution of ~3 keV FWHM, and rise time of ~50 ns with 19 of the 127 detector pixels instrumented. We have demonstrated the coincident detection of β particles and recoil protons from neutron β decay, using ultracold neutrons at the Los Alamos Neutron Science Center, . The fully instrumented detection system willmore » be implemented in the UCNB and Nab experiments, to determine the neutron β decay parameters B, a, and b.« less

  10. Lung cancer screening: fourteen year experience of the Pamplona early detection program (P-IELCAP).

    PubMed

    Sanchez-Salcedo, Pablo; Berto, Juan; de-Torres, Juan P; Campo, Arantzazu; Alcaide, Ana B; Bastarrika, Gorka; Pueyo, Jesús C; Villanueva, Alberto; Echeveste, José I; Lozano, Maria D; García-Velloso, María J; Seijo, Luis M; García, Javier; Torre, Wenceslao; Pajares, Maria J; Pío, Ruben; Montuenga, Luis M; Zulueta, Javier J

    2015-04-01

    European experience regarding lung cancer screening using low-dose chest CT (LDCT) is available. However, there is limited data on the Spanish experience in this matter. Our aim is to present the results from the longest ongoing screening program in Spain. The Pamplona International Early Lung Cancer Detection Program (P-IELCAP) is actively screening participants for lung cancer using LDCT since year 2000 following the IELCAP protocol, including spirometric assessments. Men and women, ≥40 years of age, current or former smokers with a tobacco history of ≥10 pack-years are included. Results are compared to those from other European trials. A total of 2989 participants were screened until March 2014 (73% male). A median of 2 (IQR 1-3) annual screening rounds were performed. Sixty lung cancers were detected in 53 participants (73% in StageI). Adenocarcinoma was the most frequent. The lung cancer prevalence and incidence proportion was 1.0% and 1.4%, respectively, with an annual detection rate of 0.41. The estimated 10-year survival rate among individuals with lung cancer was 70%. Chronic obstructive pulmonary disease and emphysema are important lung cancer predictors. The experience in Spain's longest lung cancer screening program is comparable to what has been described in the rest of Europe, and confirms the feasibility and efficacy of lung cancer screening using LDCT. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  11. MOSIDEO/CIRFA Experiments on Behavior and Detection of Oil in Ice

    NASA Astrophysics Data System (ADS)

    Petrich, Chris

    2017-04-01

    Arctic operations in the presence of sea ice present a challenge to sustainable operations. In order to optimize planning and minimize impact of inadvertent oil spills, oil-in-ice experiments were performed at the Hamburgische Schiffbau-Versuchsanstalt (HSVA) in spring 2017 by participants of Norut Narvik, UiT - The Arctic University of Norway, NTNU, Norut - Northern Research Institute, Université de Rennes 1, University of Alaska Fairbanks, and Ocean Visuals. Following an under-ice spill and simulated springtime warming, investigations were performed on the microscopic movement and distribution of oil in the sea ice pore space and the detectability of oil as it approaches the surface. Combining expertise of two research projects, the experiments present a unique opportunity to link the signals of a range of surface detection techniques, including electromagnetic (radar, tomographic SAR) and optical (fluorescent, hyperspectral), to the microscopic distribution of oil in sea ice investigated by X-ray computed tomography (CT). Predicting the behavior of oil in ice based on environmental conditions will help optimize the use of methods for spill detection and response. The experiments and initial results will be presented.

  12. Crack-Detection Experiments on Simulated Turbine Engine Disks in NASA Glenn Research Center's Rotordynamics Laboratory

    NASA Technical Reports Server (NTRS)

    Woike, Mark R.; Abdul-Aziz, Ali

    2010-01-01

    The development of new health-monitoring techniques requires the use of theoretical and experimental tools to allow new concepts to be demonstrated and validated prior to use on more complicated and expensive engine hardware. In order to meet this need, significant upgrades were made to NASA Glenn Research Center s Rotordynamics Laboratory and a series of tests were conducted on simulated turbine engine disks as a means of demonstrating potential crack-detection techniques. The Rotordynamics Laboratory consists of a high-precision spin rig that can rotate subscale engine disks at speeds up to 12,000 rpm. The crack-detection experiment involved introducing a notch on a subscale engine disk and measuring its vibration response using externally mounted blade-tip-clearance sensors as the disk was operated at speeds up to 12 000 rpm. Testing was accomplished on both a clean baseline disk and a disk with an artificial crack: a 50.8-mm- (2-in.-) long introduced notch. The disk s vibration responses were compared and evaluated against theoretical models to investigate how successful the technique was in detecting cracks. This paper presents the capabilities of the Rotordynamics Laboratory, the baseline theory and experimental setup for the crack-detection experiments, and the associated results from the latest test campaign.

  13. The subjective experience of object recognition: comparing metacognition for object detection and object categorization.

    PubMed

    Meuwese, Julia D I; van Loon, Anouk M; Lamme, Victor A F; Fahrenfort, Johannes J

    2014-05-01

    Perceptual decisions seem to be made automatically and almost instantly. Constructing a unitary subjective conscious experience takes more time. For example, when trying to avoid a collision with a car on a foggy road you brake or steer away in a reflex, before realizing you were in a near accident. This subjective aspect of object recognition has been given little attention. We used metacognition (assessed with confidence ratings) to measure subjective experience during object detection and object categorization for degraded and masked objects, while objective performance was matched. Metacognition was equal for degraded and masked objects, but categorization led to higher metacognition than did detection. This effect turned out to be driven by a difference in metacognition for correct rejection trials, which seemed to be caused by an asymmetry of the distractor stimulus: It does not contain object-related information in the detection task, whereas it does contain such information in the categorization task. Strikingly, this asymmetry selectively impacted metacognitive ability when objective performance was matched. This finding reveals a fundamental difference in how humans reflect versus act on information: When matching the amount of information required to perform two tasks at some objective level of accuracy (acting), metacognitive ability (reflecting) is still better in tasks that rely on positive evidence (categorization) than in tasks that rely more strongly on an absence of evidence (detection).

  14. Human observer detection experiments with mammograms and power-law noise.

    PubMed

    Burgess, A E; Jacobson, F L; Judy, P F

    2001-04-01

    We determined contrast thresholds for lesion detection as a function of lesion size in both mammograms and filtered noise backgrounds with the same average power spectrum, P(f)=B/f3. Experiments were done using hybrid images with digital images of tumors added to digitized normal backgrounds, displayed on a monochrome monitor. Four tumors were extracted from digitized specimen radiographs. The lesion sizes were varied by digital rescaling to cover the range from 0.5 to 16 mm. Amplitudes were varied to determine the value required for 92% correct detection in two-alternative forced-choice (2AFC) and 90% for search experiments. Three observers participated, two physicists and a radiologist. The 2AFC mammographic results demonstrated a novel contrast-detail (CD) diagram with threshold amplitudes that increased steadily (with slope of 0.3) with increasing size for lesions larger than 1 mm. The slopes for prewhitening model observers were about 0.4. Human efficiency relative to these models was as high as 90%. The CD diagram slopes for the 2AFC experiments with filtered noise were 0.44 for humans and 0.5 for models. Human efficiency relative to the ideal observer was about 40%. The difference in efficiencies for the two types of backgrounds indicates that breast structure cannot be considered to be pure random noise for 2AFC experiments. Instead, 2AFC human detection with mammographic backgrounds is limited by a combination of noise and deterministic masking effects. The search experiments also gave thresholds that increased with lesion size. However, there was no difference in human results for mammographic and filtered noise backgrounds, suggesting that breast structure can be considered to be pure random noise for this task. Our conclusion is that, in spite of the fact that mammographic backgrounds have nonstationary statistics, models based on statistical decision theory can still be applied successfully to estimate human performance.

  15. Study on simulation and experiment of laser micro-Doppler effect for detecting complex vibration

    NASA Astrophysics Data System (ADS)

    Yuan, Shuai; Zhang, Juan; Liu, Mei-juan; Zhang, Jun

    2013-08-01

    The spectrum of radar signal will be modulated by moving target or vibration and turning part of the target, this is called micro-Doppler effect. It is a new way of using micro-Doppler effect to realize the feature extraction and target recognition. Because the complex vibration target has more complicated frequency component than the single frequency target, so it is very useful to do the research of simulation and experiment of laser micro-Doppler effect for detecting complex vibration. In this paper, the research on simulation and experiment of laser micro-Doppler effect for detecting complex vibration of moving target was developed based on the simulation research of micro-Doppler effect in lidar. Firstly, the geometry of complex vibrating target detection in radar was established. Secondly, the simulation and experiment signal sources were compared and also the returned signals in radar of the simulation and experiment were compared, the compared results showed that the two complex signal sources were very similar, and the frequency change trend of returned signals in radar was the same. Thirdly, joint time-frequency analysis method of the reassigned smoothed pseudo Wigner-Ville distribution (RSPWVD) was introduced to analyze the signals. The results showed that in RSPWVD, the waveform of the vibration target, the target vibration period, the Doppler frequency shift and the target's speed can be got. The simulation results and the experiment results got by the RSPWVD had the basically same frequency characteristics. So the RSPWVD can reflect very well the micro-Doppler characteristics of moving target's complex vibration. In conclusion it proved the validity of the simulated model, also it proved that using this time-frequency method to analyze the micro-Doppler signal of complex vibration was correct. And it laid the foundation of further using lidar to realize the classification and identification of target.

  16. Increasing sensitivity of pulse EPR experiments using echo train detection schemes.

    PubMed

    Mentink-Vigier, F; Collauto, A; Feintuch, A; Kaminker, I; Tarle, V; Goldfarb, D

    2013-11-01

    Modern pulse EPR experiments are routinely used to study the structural features of paramagnetic centers. They are usually performed at low temperatures, where relaxation times are long and polarization is high, to achieve a sufficient Signal/Noise Ratio (SNR). However, when working with samples whose amount and/or concentration are limited, sensitivity becomes an issue and therefore measurements may require a significant accumulation time, up to 12h or more. As the detection scheme of practically all pulse EPR sequences is based on the integration of a spin echo--either primary, stimulated or refocused--a considerable increase in SNR can be obtained by replacing the single echo detection scheme by a train of echoes. All these echoes, generated by Carr-Purcell type sequences, are integrated and summed together to improve the SNR. This scheme is commonly used in NMR and here we demonstrate its applicability to a number of frequently used pulse EPR experiments: Echo-Detected EPR, Davies and Mims ENDOR (Electron-Nuclear Double Resonance), DEER (Electron-Electron Double Resonance|) and EDNMR (Electron-Electron Double Resonance (ELDOR)-Detected NMR), which were combined with a Carr-Purcell-Meiboom-Gill (CPMG) type detection scheme at W-band. By collecting the transient signal and integrating a number of refocused echoes, this detection scheme yielded a 1.6-5 folds SNR improvement, depending on the paramagnetic center and the pulse sequence applied. This improvement is achieved while keeping the experimental time constant and it does not introduce signal distortion.