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Sample records for probing hidden sector

  1. Spectroscopy as a test of Coulomb's law: A probe of the hidden sector

    NASA Astrophysics Data System (ADS)

    Jaeckel, Joerg; Roy, Sabyasachi

    2010-12-01

    High precision spectroscopy can provide a sensitive tool to test Coulomb’s law on atomic length scales. This can then be used to constrain particles such as extra “hidden” photons or minicharged particles that are predicted in many extensions of the standard model, and which cause small deviations from Coulomb’s law. In this paper we use a variety of transitions in atomic hydrogen, hydrogenic ions, and exotic atoms to probe Coulomb’s law. This extends the region of pure Coulomb’s law tests to larger masses. For hidden photons and minicharged particles this region is already tested by other astrophysical and laboratory probes. However, future tests of true muonium and muonic atoms are likely to probe new parameter space and therefore have good discovery potential for new physics. Finally, we investigate whether the discrepancy between the theoretical calculation of the 2s1/2F=1-2p3/2F=2 transition in muonic hydrogen and its recent experimental measurement at PSI can be explained by the existence of a hidden photon. This explanation is ruled out by measurements of the Lamb shift in ordinary hydrogen.

  2. Probing Dark Forces and Light Hidden Sectors at Low-Energy e+e- Colliders

    SciTech Connect

    Essig, Rouven; Schuster, Philip; Toro, Natalia; /Stanford U., ITP

    2009-06-19

    A dark sector - a new non-Abelian gauge group Higgsed or confined near the GeV scale - can be spectacularly probed in low-energy e{sup +}e{sup -} collisions. A low-mass dark sector can explain the annual modulation signal reported by DAMA/LIBRA and the PAMELA, ATIC, and INTEGRAL observations by generating small mass splittings and new interactions for weak-scale dark matter. Some of these observations may be the first signs of a low-mass dark sector that collider searches can definitively confirm. Production and decay of {Omicron}(GeV)-mass dark states is mediated by a Higgsed Abelian gauge boson that mixes kinetically with hypercharge. Existing data from BaBar, BELLE, CLEO-c, and KLOE may contain thousands of striking dark-sector events with a high multiplicity of leptons that reconstruct mass resonances and possibly displaced vertices. We discuss the production and decay phenomenology of Higgsed and confined dark sectors and propose e{sup +}e{sup -} collider search strategies. We also use the DAMA/LIBRA signal to estimate the production cross-sections and decay lifetimes for dark-sector states.

  3. Probing dark forces and light hidden sectors at low-energy e+e- colliders

    NASA Astrophysics Data System (ADS)

    Essig, Rouven; Schuster, Philip; Toro, Natalia

    2009-07-01

    A dark sector—a new non-Abelian gauge group Higgsed or confined near the GeV scale—can be spectacularly probed in low-energy e+e- collisions. A low-mass dark sector can explain the annual modulation signal reported by DAMA/LIBRA and the PAMELA, ATIC, and INTEGRAL observations by generating small mass splittings and new interactions for weak-scale dark matter. Some of these observations may be the first signs of a low-mass dark sector that collider searches can definitively confirm. Production and decay of O(GeV)-mass dark states is mediated by a Higgsed Abelian gauge boson that mixes kinetically with hypercharge. Existing data from BABAR, BELLE, CLEO-c, and KLOE may contain thousands of striking dark-sector events with a high multiplicity of leptons that reconstruct mass resonances and possibly displaced vertices. We discuss the production and decay phenomenology of Higgsed and confined dark sectors and propose e+e- collider search strategies. We also use the DAMA/LIBRA signal to estimate the production cross sections and decay lifetimes for dark-sector states.

  4. Thermal relics in hidden sectors

    SciTech Connect

    Feng, Jonathan L; Tu, Huitzu; Yu, Hai-Bo E-mail: huitzut@uci.edu

    2008-10-15

    Dark matter may be hidden, with no standard model gauge interactions. At the same time, in WIMPless models (WIMP: weakly interacting massive particles) with hidden matter masses proportional to hidden gauge couplings squared, the hidden dark matter's thermal relic density may naturally be in the right range, preserving the key quantitative virtue of WIMPs. We consider this possibility in detail. We first determine model-independent constraints on hidden sectors from big bang nucleosynthesis and the cosmic microwave background. Contrary to conventional wisdom, large hidden sectors are easily accommodated. A flavour-free version of the standard model is allowed if the hidden sector is just 30% colder than the observable sector after reheating. Alternatively, if the hidden sector contains a one-generation version of the standard model with characteristic mass scale below 1 MeV, even identical reheating temperatures are allowed. We then analyse hidden sector freeze-out in detail for a concrete model, solving the Boltzmann equation numerically and explaining the results from both observable and hidden sector points of view. We find that WIMPless dark matter does indeed obtain the correct relic density for masses in the range keV{approx}hidden sectors reheat to the same temperature, and is raised to the MeV scale if the hidden sector is ten times colder. WIMPless dark matter therefore generalizes the WIMP paradigm to the largest mass range possible for viable thermal relics and provides a unified framework for exploring dark matter signals across nine orders of magnitude in dark matter mass.

  5. Lepton mixing from the hidden sector

    NASA Astrophysics Data System (ADS)

    Ludl, P. O.; Smirnov, A. Yu.

    2015-10-01

    Experimental results indicate a possible relation between the lepton and quark mixing matrices of the form UPMNS≈VCKM†UX , where UX is a matrix with special structure related to the mechanism of neutrino mass generation. We propose a framework which can realize such a relation. The main ingredients of the framework are the double seesaw mechanism, SO(10) grand unification and a hidden sector of theory. The latter is composed of singlets (fermions and bosons) of the grand unified theory (GUT) symmetry with masses between the GUT and Planck scale. The interactions in this sector obey certain symmetries Ghidden. We explore the conditions under which symmetries Ghidden can produce flavor structures in the visible sector. Here the key elements are the basis-fixing symmetry and mediators which communicate information about properties of the hidden sector to the visible one. The interplay of SO(10) symmetry, basis-fixing symmetry identified as Z2×Z2 and Ghidden can lead to the required form of UX. A different kind of new physics is responsible for generation of the CKM mixing. We present the simplest realizations of the framework which differ by nature of the mediators and by symmetries of the hidden sector.

  6. Hidden sector behind the CKM matrix

    NASA Astrophysics Data System (ADS)

    Okawa, Shohei; Omura, Yuji

    2017-08-01

    The small quark mixing, described by the Cabibbo-Kobayashi-Maskawa (CKM) matrix in the standard model, may be a clue to reveal new physics around the TeV scale. We consider a simple scenario that extra particles in a hidden sector radiatively mediate the flavor violation to the quark sector around the TeV scale and effectively realize the observed CKM matrix. The lightest particle in the hidden sector, whose contribution to the CKM matrix is expected to be dominant, is a good dark matter (DM) candidate. There are many possible setups to describe this scenario, so that we investigate some universal predictions of this kind of model, focusing on the contribution of DM to the quark mixing and flavor physics. In this scenario, there is an explicit relation between the CKM matrix and flavor violating couplings, such as four-quark couplings, because both are radiatively induced by the particles in the hidden sector. Then, we can explicitly find the DM mass region and the size of Yukawa couplings between the DM and quarks, based on the study of flavor physics and DM physics. In conclusion, we show that DM mass in our scenario is around the TeV scale, and the Yukawa couplings are between O (0.01 ) and O (1 ). The spin-independent DM scattering cross section is estimated as O (10-9) [pb]. An extra colored particle is also predicted at the O (10 ) TeV scale.

  7. Low-energy signals from kinetic mixing with a warped abelian hidden sector

    NASA Astrophysics Data System (ADS)

    McDonald, Kristian L.; Morrissey, David E.

    2011-02-01

    We investigate the detailed phenomenology of a light Abelian hidden sector in the Randall-Sundrum framework. Relative to other works with light hidden sectors, the main new feature is a tower of hidden Kaluza-Klein vectors that kinetically mix with the Standard Model photon and Z. We investigate the decay properties of the hidden sector fields in some detail, and develop an approach for calculating processes initiated on the ultraviolet brane of a warped space with large injection momentum relative to the infrared scale. Using these results, we determine the detailed bounds on the light warped hidden sector from precision electroweak measurements and low-energy experiments. We find viable regions of parameter space that lead to significant production rates for several of the hidden Kaluza-Klein vectors in meson factories and fixed-target experiments. This offers the possibility of exploring the structure of an extra spacetime dimension with lower-energy probes.

  8. More visible effects of the hidden sector

    SciTech Connect

    Murayama, Hitoshi; Nomura, Yasunori; Poland, David

    2008-01-01

    There is a growing appreciation that hidden sector dynamics may affect the supersymmetry breaking parameters in the visible sector (supersymmetric standard model), especially when the dynamics is strong and superconformal. We point out that there are effects that have not been previously discussed in the literature. For example, the gaugino masses are suppressed relative to the gravitino mass. We discuss their implications in the context of various mediation mechanisms. The issues discussed include anomaly mediation with singlets, the {mu} (B{mu}) problem in gauge and gaugino mediation, and distinct mass spectra for the superparticles that have not been previously considered.

  9. More visible effects of the hidden sector

    SciTech Connect

    Murayama, Hitoshi; Murayama, Hitoshi; Nomura, Yasunori; Poland, David

    2007-09-06

    There is a growing appreciation that hidden sector dynamics may affect the supersymmetry breaking parameters in the visible sector (supersymmetric standard model), especially when the dynamics is strong and superconformal. We point out that there are effects that have not been previously discussed in the literature. For example, the gaugino masses are suppressed relative to the gravitino mass. We discuss their implications in the context of various mediation mechanisms. The issues discussed include anomaly mediation with singlets, the mu (B mu) problem in gauge and gaugino mediation, and distinct mass spectra for the superparticles that have not been previously considered.

  10. Abelian Hidden Sectors at a GeV

    SciTech Connect

    Morrissey, David E.; Poland, David; Zurek, Kathryn; /Fermilab /Michigan U.

    2009-04-16

    We discuss mechanisms for naturally generating GeV-scale hidden sectors in the context of weak-scale supersymmetry. Such low mass scales can arise when hidden sectors are more weakly coupled to supersymmetry breaking than the visible sector, as happens when supersymmetry breaking is communicated to the visible sector by gauge interactions under which the hidden sector is uncharged, or if the hidden sector is sequestered from gravity-mediated supersymmetry breaking. We study these mechanisms in detail in the context of gauge and gaugino mediation, and present specific models of Abelian GeV-scale hidden sectors. In particular, we discuss kinetic mixing of a U(1){sub x} gauge force with hypercharge, singlets or bi-fundamentals which couple to both sectors, and additional loop effects. Finally, we investigate the possible relevance of such sectors for dark matter phenomenology, as well as for low- and high-energy collider searches.

  11. Supersymmetric leptogenesis with a light hidden sector

    SciTech Connect

    De Simone, Andrea; Garny, Mathias; Ibarra, Alejandro; Weniger, Christoph E-mail: mathias.garny@ph.tum.de E-mail: christoph.weniger@desy.de

    2010-07-01

    Supersymmetric scenarios incorporating thermal leptogenesis as the origin of the observed matter-antimatter asymmetry generically predict abundances of the primordial elements which are in conflict with observations. In this paper we propose a simple way to circumvent this tension and accommodate naturally thermal leptogenesis and primordial nucleosynthesis. We postulate the existence of a light hidden sector, coupled very weakly to the Minimal Supersymmetric Standard Model, which opens up new decay channels for the next-to-lightest supersymmetric particle, thus diluting its abundance during nucleosynthesis. We present a general model-independent analysis of this mechanism as well as two concrete realizations, and describe the relevant cosmological and astrophysical bounds and implications for this dark matter scenario. Possible experimental signatures at colliders and in cosmic-ray observations are also discussed.

  12. Reheating the Standard Model from a hidden sector

    NASA Astrophysics Data System (ADS)

    Tenkanen, Tommi; Vaskonen, Ville

    2016-10-01

    We consider a scenario where the inflaton decays to a hidden sector thermally decoupled from the visible Standard Model sector. A tiny portal coupling between the hidden and the visible sectors later heats the visible sector so that the Standard Model degrees of freedom come to dominate the energy density of the Universe before big bang nucleosynthesis. We find that this scenario is viable, although obtaining the correct dark matter abundance and retaining successful big bang nucleosynthesis is not obvious. We also show that the isocurvature perturbations constituted by a primordial Higgs condensate are not problematic for the viability of the scenario.

  13. Dark Forces and Dark Matter in a Hidden Sector

    NASA Astrophysics Data System (ADS)

    Andreas, Sarah

    2012-01-01

    Hidden sectors in connection with GeV-scale dark forces and dark matter are not only a common feature of physics beyond the Standard Model such as string theory and SUSY but are also phenomenologically of great interest regarding recent astrophysical observations. The hidden photon in particular is also searched for and constrained by laboratory experiments, the current status of which will be presented here. Furthermore, several models of hidden sectors containing in addition a dark matter particle will be examined regarding their consistency with the dark matter relic abundance and direct detection experiments.

  14. Dark matter antibaryons from a supersymmetric hidden sector

    NASA Astrophysics Data System (ADS)

    Blinov, Nikita; Morrissey, David E.; Sigurdson, Kris; Tulin, Sean

    2012-11-01

    The cosmological origin of both dark and baryonic matter can be explained through a unified mechanism called hylogenesis where baryon and antibaryon numbers are divided between the visible sector and a GeV-scale hidden sector, while the Universe remains net baryon symmetric. The “missing” antibaryons, in the form of exotic hidden states, are the dark matter. We study model-building, cosmological, and phenomenological aspects of this scenario within the framework of supersymmetry, which naturally stabilizes the light hidden sector and electroweak mass scales. Inelastic dark matter scattering on visible matter destroys nucleons, and nucleon decay searches offer a novel avenue for the direct detection of the hidden antibaryonic dark matter sea.

  15. Diurnal modulation signal from dissipative hidden sector dark matter

    NASA Astrophysics Data System (ADS)

    Foot, R.; Vagnozzi, S.

    2015-09-01

    We consider a simple generic dissipative dark matter model: a hidden sector featuring two dark matter particles charged under an unbroken U(1) ‧ interaction. Previous work has shown that such a model has the potential to explain dark matter phenomena on both large and small scales. In this framework, the dark matter halo in spiral galaxies features nontrivial dynamics, with the halo energy loss due to dissipative interactions balanced by a heat source. Ordinary supernovae can potentially supply this heat provided kinetic mixing interaction exists with strength ɛ ∼10-9. This type of kinetically mixed dark matter can be probed in direct detection experiments. Importantly, this self-interacting dark matter can be captured within the Earth and shield a dark matter detector from the halo wind, giving rise to a diurnal modulation effect. We estimate the size of this effect for detectors located in the Southern hemisphere, and find that the modulation is large (≳ 10%) for a wide range of parameters.

  16. Dark matter and dark forces from a supersymmetric hidden sector

    NASA Astrophysics Data System (ADS)

    Andreas, S.; Goodsell, M. D.; Ringwald, A.

    2013-01-01

    We show that supersymmetric “dark force” models with gravity mediation are viable. To this end, we analyze a simple string-inspired supersymmetric hidden sector model that interacts with the visible sector via kinetic mixing of a light Abelian gauge boson with the hypercharge. We include all induced interactions with the visible sector such as neutralino mass mixing and the Higgs portal term. We perform a detailed parameter space scan comparing the produced dark matter relic abundance and direct-detection cross sections to current experiments.

  17. Probing the string winding sector

    NASA Astrophysics Data System (ADS)

    Aldazabal, Gerardo; Mayo, Martín; Nuñez, Carmen

    2017-03-01

    We probe a slice of the massive winding sector of bosonic string theory from toroidal compactifications of Double Field Theory (DFT). This string subsector corresponds to states containing one left and one right moving oscillators. We perform a generalized Kaluza Klein compactification of DFT on generic 2 n-dimensional toroidal constant backgrounds and show that, up to third order in fluctuations, the theory coincides with the corresponding effective theory of the bosonic string compactified on n-dimensional toroidal constant backgrounds, obtained from three-point amplitudes. The comparison between both theories is facilitated by noticing that generalized diffeomorphisms in DFT allow to fix generalized harmonic gauge conditions that help in identifying the physical degrees of freedom. These conditions manifest as conformal anomaly cancellation requirements on the string theory side. The explicit expression for the gauge invariant effective action containing the physical massless sector (gravity+antisymmetric+gauge+ scalar fields) coupled to towers of generalized Kaluza Klein massive states (corresponding to compact momentum and winding modes) is found. The action acquires a very compact form when written in terms of fields carrying O( n, n) indices, and is explicitly T-duality invariant. The global algebra associated to the generalized Kaluza Klein compactification is discussed.

  18. Hidden sector DM models and Higgs physics

    SciTech Connect

    Ko, P.

    2014-06-24

    We present an extension of the standard model to dark sector with an unbroken local dark U(1){sub X} symmetry. Including various singlet portal interactions provided by the standard model Higgs, right-handed neutrinos and kinetic mixing, we show that the model can address most of phenomenological issues (inflation, neutrino mass and mixing, baryon number asymmetry, dark matter, direct/indirect dark matter searches, some scale scale puzzles of the standard collisionless cold dark matter, vacuum stability of the standard model Higgs potential, dark radiation) and be regarded as an alternative to the standard model. The Higgs signal strength is equal to one as in the standard model for unbroken U(1){sub X} case with a scalar dark matter, but it could be less than one independent of decay channels if the dark matter is a dark sector fermion or if U(1){sub X} is spontaneously broken, because of a mixing with a new neutral scalar boson in the models.

  19. Cosmic strings in hidden sectors: 2. Cosmological and astrophysical signatures

    SciTech Connect

    Long, Andrew J.; Vachaspati, Tanmay

    2014-12-18

    Cosmic strings can arise in hidden sector models with a spontaneously broken Abelian symmetry group. We have studied the couplings of the Standard Model fields to these so-called dark strings in the companion paper. Here we survey the cosmological and astrophysical observables that could be associated with the presence of dark strings in our universe with an emphasis on low-scale models, perhaps TeV. Specifically, we consider constraints from nucleosynthesis and CMB spectral distortions, and we calculate the predicted fluxes of diffuse gamma ray cascade photons and cosmic rays. For strings as light as TeV, we find that the predicted level of these signatures is well below the sensitivity of the current experiments, and therefore low scale cosmic strings in hidden sectors remain unconstrained. Heavier strings with a mass scale in the range 10{sup 13} GeV to 10{sup 15} GeV are at tension with nucleosynthesis constraints.

  20. Cosmic strings in hidden sectors: 2. Cosmological and astrophysical signatures

    SciTech Connect

    Long, Andrew J.; Vachaspati, Tanmay E-mail: tvachasp@asu.edu

    2014-12-01

    Cosmic strings can arise in hidden sector models with a spontaneously broken Abelian symmetry group. We have studied the couplings of the Standard Model fields to these so-called dark strings in the companion paper. Here we survey the cosmological and astrophysical observables that could be associated with the presence of dark strings in our universe with an emphasis on low-scale models, perhaps TeV . Specifically, we consider constraints from nucleosynthesis and CMB spectral distortions, and we calculate the predicted fluxes of diffuse gamma ray cascade photons and cosmic rays. For strings as light as TeV, we find that the predicted level of these signatures is well below the sensitivity of the current experiments, and therefore low scale cosmic strings in hidden sectors remain unconstrained. Heavier strings with a mass scale in the range 10{sup 13} GeV to 10{sup 15} GeV are at tension with nucleosynthesis constraints.

  1. New Experimental Limit on Photon Hidden-Sector Paraphoton Mixing

    SciTech Connect

    Afanaciev, Andrei; Afanasev, Andrei; Baker, O.; Beard, Kevin; Biallas, George; Boyce, James; Minarni, Minarni; Ramdon, Roopchan; Michelle D. Shinn; Slocum, P.

    2009-01-01

    We report on the first results of a search for optical-wavelength photons mixing with hypothetical hidden-sector paraphotons in the mass range between 10^-5 and 10^-2 electron volts for a mixing parameter greater than 10^-7. This was a generation-regeneration experiment using the "light shining through a wall" technique in which regenerated photons are searched for downstream of an optical barrier that separates it from an upstream generation region. The new limits presented here are approximately three times more sensitive to this mixing than the best previous measurement. The present results indicate no evidence for photon-paraphoton mixing for the range of parameters investigated.

  2. Multilepton signatures of a hidden sector in rare B decays

    SciTech Connect

    Batell, Brian; Pospelov, Maxim; Ritz, Adam

    2011-03-01

    We explore the sensitivity of flavor-changing b{yields}s transitions to a (sub-) GeV hidden sector with generic couplings to the standard model through the Higgs, vector, and axion portals. The underlying two-body decays of B mesons, B{yields}X{sub s}S, and B{sup 0}{yields}SS, where S denotes a generic new GeV-scale particle, may significantly enhance the yield of monochromatic lepton pairs in the final state via prompt S{yields}ll decays. Existing measurements of the charged lepton spectrum in neutral-current semileptonic B decays provide bounds on the parameters of the light sector that are significantly more stringent than the requirements of naturalness. New search modes, such as B{yields}X{sub s}+n(ll) and B{sup 0}{yields}n(ll) with n{>=}2, can provide additional sensitivity to scenarios in which both the Higgs and vector portals are active, and are accessible to (super-) B factories and hadron colliders.

  3. Low scale gravity mediation with warped extra dimension and collider phenomenology on the hidden sector

    SciTech Connect

    Itoh, Hideo; Okada, Nobuchika; Yamashita, Toshifumi

    2006-09-01

    We propose a scenario of gravity mediated supersymmetry breaking (gravity mediation) in a supersymmetric Randall-Sundrum model. In our setup, both the visible sector and the hidden sector coexist on the infrared (IR) brane. We introduce the Polonyi model as a simple hidden sector. Because of the warped metric, the effective cutoff scale on the IR brane is 'warped down', so that the gravity mediation occurs at a low scale. As a result, the gravitino is naturally the lightest superpartner (LSP) and contact interactions between the hidden and the visible sector fields become stronger. We address phenomenologies for various IR cutoff scales. In particular, we investigate collider phenomenology involving a scalar field (Polonyi field) in the hidden sector for the case with the IR cutoff around 10 TeV. We find a possibility that the hidden sector scalar can be produced at the LHC and the international linear collider (ILC). Interestingly, the scalar behaves like the Higgs boson of the standard model in the production process, while its decay process is quite different and, once produced, it will provide us with a very clean signature. The hidden sector may be no longer hidden.

  4. WIMPless dark matter from non-Abelian hidden sectors with anomaly-mediated supersymmetry breaking

    NASA Astrophysics Data System (ADS)

    Feng, Jonathan L.; Shadmi, Yael

    2011-05-01

    In anomaly-mediated supersymmetry breaking models, superpartner masses are proportional to couplings squared. Their hidden sectors therefore naturally contain WIMPless dark matter, particles whose thermal relic abundance is guaranteed to be of the correct size, even though they are not weakly interacting massive particles. We study viable dark matter candidates in WIMPless anomaly-mediated supersymmetry breaking models with non-Abelian hidden sectors and highlight unusual possibilities that emerge in even the simplest models. In one example with a pure SU(N) hidden sector, stable hidden gluinos freeze out with the correct relic density, but have an extremely low, but natural, confinement scale, providing a framework for self-interacting dark matter. In another simple scenario, hidden gluinos freeze out and decay to visible Winos with the correct relic density, and hidden glueballs may either be stable, providing a natural framework for mixed cold-hot dark matter, or may decay, yielding astrophysical signals. Last, we present a model with light hidden pions that may be tested with improved constraints on the number of nonrelativistic degrees of freedom. All of these scenarios are defined by a small number of parameters, are consistent with gauge coupling unification, preserve the beautiful connection between the weak scale and the observed dark matter relic density, and are natural, with relatively light visible superpartners. We conclude with comments on interesting future directions.

  5. Hidden sector monopole, vector dark matter and dark radiation with Higgs portal

    SciTech Connect

    Baek, Seungwon; Ko, P.; Park, Wan-Il E-mail: pko@kias.re.kr

    2014-10-01

    We show that the 't Hooft-Polyakov monopole model in the hidden sector with Higgs portal interaction makes a viable dark matter model, where monopole and massive vector dark matter (VDM) are stable due to topological conservation and the unbroken subgroup U(1 {sub X}. We show that, even though observed CMB data requires the dark gauge coupling to be quite small, a right amount of VDM thermal relic can be obtained via s-channel resonant annihilation for the mass of VDM close to or smaller than the half of SM higgs mass, thanks to Higgs portal interaction. Monopole relic density turns out to be several orders of magnitude smaller than the observed dark matter relic density. Direct detection experiments, particularly, the projected XENON1T experiment, may probe the parameter space where the dark Higgs is lighter than ∼< 50 GeV. In addition, the dark photon associated with the unbroken U(1 {sub X} contributes to the radiation energy density at present, giving Δ N{sub eff}{sup ν} ∼ 0.1 as the extra relativistic neutrino species.

  6. Hidden sector dark matters and elusive Higgs boson(s) at the LHC

    SciTech Connect

    Ko, P.

    2012-07-27

    We consider two types of hidden sector dark matters (DM's), with and without QCD-like new strong interaction with confinement properties, and their interplays with the Standard Model (SM) Higgs boson. Assuming the hidden sector has only fermions (and gauge bosons in case of strongly interacting hidden sector), we have to introduce a real singlet scalar boson S as a messenger between the SM and the hidden sector dark matters. This singlet scalar will mix with the SM Higgs boson h, and we expect there are two Higgs-like scalar bosons H{sub 1} and H{sub 2}. Imposing all the relevant constraints from collider search bounds on Higgs boson, DM scattering cross section on proton and thermal relic density, we find that one of the two Higgs-like scalar bosons can easily escape the detections at the LHC. Recent results on the Higgs-like new boson with mass around with 125 GeV from the LHC will constrain this class of models, which is left for future study.

  7. 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.

  8. Asymmetric dark matter from a GeV hidden sector

    SciTech Connect

    Cohen, Timothy; Zurek, Kathryn M.; Phalen, Daniel J.; Pierce, Aaron

    2010-09-01

    Asymmetric dark matter (ADM) models relate the dark matter (DM) density to the baryon asymmetry, so that a natural mass scale for ADM is around a few GeV. In existing models of ADM, this mass scale is unexplained; here we generate this GeV scale for DM) from the weak scale via gauge kinetic mixing with a new Abelian dark force. In addition, this dark sector provides an efficient mechanism for suppressing the symmetric abundance of DM through annihilations to the dark photon. We augment this sector with a higher dimensional operator responsible for communicating the baryon asymmetry to the dark sector. Our framework also provides a DM candidate for gauge mediation models. It results in a direct detection cross section of interest for current experiments: {sigma}{sub p} < or approx. 10{sup -41} cm{sup 2} for DM masses in the range 1-15 GeV.

  9. Hidden Sector Dark Matter Models for the Galactic Center Gamma-Ray Excess

    SciTech Connect

    Berlin, Asher; Gratia, Pierre; Hooper, Dan; McDermott, Samuel D.

    2014-07-24

    The gamma-ray excess observed from the Galactic Center can be interpreted as dark matter particles annihilating into Standard Model fermions with a cross section near that expected for a thermal relic. Although many particle physics models have been shown to be able to account for this signal, the fact that this particle has not yet been observed in direct detection experiments somewhat restricts the nature of its interactions. One way to suppress the dark matter's elastic scattering cross section with nuclei is to consider models in which the dark matter is part of a hidden sector. In such models, the dark matter can annihilate into other hidden sector particles, which then decay into Standard Model fermions through a small degree of mixing with the photon, Z, or Higgs bosons. After discussing the gamma-ray signal from hidden sector dark matter in general terms, we consider two concrete realizations: a hidden photon model in which the dark matter annihilates into a pair of vector gauge bosons that decay through kinetic mixing with the photon, and a scenario within the generalized NMSSM in which the dark matter is a singlino-like neutralino that annihilates into a pair of singlet Higgs bosons, which decay through their mixing with the Higgs bosons of the MSSM.

  10. Hidden sector dark matter models for the Galactic Center gamma-ray excess

    NASA Astrophysics Data System (ADS)

    Berlin, Asher; Gratia, Pierre; Hooper, Dan; McDermott, Samuel D.

    2014-07-01

    The gamma-ray excess observed from the Galactic Center can be interpreted as dark matter particles annihilating into standard model fermions with a cross section near that expected for a thermal relic. Although many particle physics models have been shown to be able to account for this signal, the fact that this particle has not yet been observed in direct detection experiments somewhat restricts the nature of its interactions. One way to suppress the dark matter's elastic scattering cross section with nuclei is to consider models in which the dark matter is part of a hidden sector. In such models, the dark matter can annihilate into other hidden sector particles, which then decay into standard model fermions through a small degree of mixing with the photon, Z, or Higgs bosons. After discussing the gamma-ray signal from hidden sector dark matter in general terms, we consider two concrete realizations: a hidden photon model in which the dark matter annihilates into a pair of vector gauge bosons that decay through kinetic mixing with the photon, and a scenario within the generalized next-to-minimal supersymmetric standard model in which the dark matter is a singlino-like neutralino that annihilates into a pair of singlet Higgs bosons, which decay through their mixing with the Higgs bosons of the minimal supersymmetric standard model.

  11. Probing the non-minimal Higgs sector at the SSC

    SciTech Connect

    Gunion, J.F.; Haber, H.E.; Komamiya, S.; Yamamoto, H.; Barbaro-Galtieri, A.

    1987-11-01

    Non-minimal Higgs sectors occur in the Standard Model with more than one Higgs doublet, as well as in theories that go beyond the Standard Model. In this report, we discuss how Higgs search strategies must be altered, with respect to the Standard Model approaches, in order to probe the non-minimal Higgs sectors at the SSC.

  12. 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.

  13. Top partner probes of extended Higgs sectors

    NASA Astrophysics Data System (ADS)

    Kearney, John; Pierce, Aaron; Thaler, Jesse

    2013-08-01

    Natural theories of the weak scale often include fermionic partners of the top quark. If the electroweak symmetry breaking sector contains scalars beyond a single Higgs doublet, then top partners can have sizable branching ratios to these extended Higgs sector states. In fact, top partner decays may provide the most promising discovery mode for such scalars, especially given the large backgrounds to direct and associated production. In this paper, we present a search strategy for top partner decays to a charged Higgs boson and a bottom quark, focusing on the case where the charged Higgs dominantly decays to third-generation quarks to yield a multi- b final state. We also discuss ways to extend this search to exotic neutral scalars decaying to bottom quark pairs.

  14. Search for Hidden Sector and Dark Matter Particles Produced at Fermilab's NuMI Target

    SciTech Connect

    Hatzikoutelis, Athanasios; Kotelnikov, Sergey; Bambah, Bindu A.; Kasetti, Siva P.

    2014-01-01

    In the long tradition of exotic searches at fixed-target experiments, we plan to use the NuMI beam-target and the NOvA Near Detector to observe potential signatures of Hidden Sector or Dark Matter particles, either directly produced within the target or through theoretically postulated mediators. Expecting mostly scattering events on electrons or nucleons as their signatures, an example of a mediator generated scalar dark matter particles is used to discuss the target production profile of a dark matter beam. This channel explores the capabilities of the detector to observe neutral-current events from electron-neutrino scattering interactions.

  15. 3.55 keV line from exciting dark matter without a hidden sector

    DOE PAGES

    Berlin, Asher; DiFranzo, Anthony; Hooper, Dan

    2015-04-24

    In this study, models in which dark matter particles can scatter into a slightly heavier state which promptly decays to the lighter state and a photon (known as eXciting Dark Matter, or XDM) have been shown to be capable of generating the 3.55 keV line observed from galaxy clusters, while suppressing the flux of such a line from smaller halos, including dwarf galaxies. In most of the XDM models discussed in the literature, this up-scattering is mediated by a new light particle, and dark matter annihilations proceed into pairs of this same light state. In these models, the dark matter andmore » the mediator effectively reside within a hidden sector, without sizable couplings to the Standard Model. In this paper, we explore a model of XDM that does not include a hidden sector. Instead, the dark matter both up-scatters and annihilates through the near resonant exchange of an O(102) GeV pseudoscalar with large Yukawa couplings to the dark matter and smaller, but non-neglibile, couplings to Standard Model fermions. The dark matter and the mediator are each mixtures of Standard Model singlets and SU(2)W doublets. We identify parameter space in which this model can simultaneously generate the 3.55 keV line and the gamma-ray excess observed from the Galactic center, without conflicting with constraints from colliders, direct detection experiments, or observations of dwarf galaxies.« less

  16. 3.55 keV line from exciting dark matter without a hidden sector

    SciTech Connect

    Berlin, Asher; DiFranzo, Anthony; Hooper, Dan

    2015-04-24

    In this study, models in which dark matter particles can scatter into a slightly heavier state which promptly decays to the lighter state and a photon (known as eXciting Dark Matter, or XDM) have been shown to be capable of generating the 3.55 keV line observed from galaxy clusters, while suppressing the flux of such a line from smaller halos, including dwarf galaxies. In most of the XDM models discussed in the literature, this up-scattering is mediated by a new light particle, and dark matter annihilations proceed into pairs of this same light state. In these models, the dark matter and the mediator effectively reside within a hidden sector, without sizable couplings to the Standard Model. In this paper, we explore a model of XDM that does not include a hidden sector. Instead, the dark matter both up-scatters and annihilates through the near resonant exchange of an O(102) GeV pseudoscalar with large Yukawa couplings to the dark matter and smaller, but non-neglibile, couplings to Standard Model fermions. The dark matter and the mediator are each mixtures of Standard Model singlets and SU(2)W doublets. We identify parameter space in which this model can simultaneously generate the 3.55 keV line and the gamma-ray excess observed from the Galactic center, without conflicting with constraints from colliders, direct detection experiments, or observations of dwarf galaxies.

  17. 3.55 keV line from exciting dark matter without a hidden sector

    NASA Astrophysics Data System (ADS)

    Berlin, Asher; DiFranzo, Anthony; Hooper, Dan

    2015-04-01

    Models in which dark matter particles can scatter into a slightly heavier state which promptly decays to the lighter state and a photon (known as eXciting Dark Matter, or XDM) have been shown to be capable of generating the 3.55 keV line observed from galaxy clusters, while suppressing the flux of such a line from smaller halos, including dwarf galaxies. In most of the XDM models discussed in the literature, this up-scattering is mediated by a new light particle, and dark matter annihilations proceed into pairs of this same light state. In these models, the dark matter and the mediator effectively reside within a hidden sector, without sizable couplings to the Standard Model. In this paper, we explore a model of XDM that does not include a hidden sector. Instead, the dark matter both up-scatters and annihilates through the near resonant exchange of an O (1 02) GeV pseudoscalar with large Yukawa couplings to the dark matter and smaller, but non-neglibile, couplings to Standard Model fermions. The dark matter and the mediator are each mixtures of Standard Model singlets and S U (2 )W doublets. We identify parameter space in which this model can simultaneously generate the 3.55 keV line and the gamma-ray excess observed from the Galactic center, without conflicting with constraints from colliders, direct detection experiments, or observations of dwarf galaxies.

  18. Fermion zero modes in the vortex background of a Chern-Simons-Higgs theory with a hidden sector

    NASA Astrophysics Data System (ADS)

    Lozano, Gustavo; Mohammadi, Azadeh; Schaposnik, Fidel A.

    2015-11-01

    In this paper we study a 2 + 1 dimensional system in which fermions are coupled to the self-dual topological vortex in U(1) × U(1) Chern-Simons theory, where both U(1) gauge symmetries are spontaneously broken. We consider two Abelian Higgs scalars with visible and hidden sectors coupled to a fermionic field through three interaction La-grangians, where one of them violates the fermion number. Using a fine tuning procedure, we could obtain the number of the fermionic zero modes which is equal to the absolute value of the sum of the vortex numbers in the visible and hidden sectors.

  19. Diurnal modulation due to self-interacting mirror and hidden sector dark matter

    SciTech Connect

    Foot, R.

    2012-04-01

    Mirror and more generic hidden sector dark matter models can simultaneously explain the DAMA, CoGeNT and CRESST-II dark matter signals consistently with the null results of the other experiments. This type of dark matter can be captured by the Earth and shield detectors because it is self-interacting. This effect will lead to a diurnal modulation in dark matter detectors. We estimate the size of this effect for dark matter detectors in various locations. For a detector located in the northern hemisphere, this effect is expected to peak in April and can be detected for optimistic parameter choices. The diurnal variation is expected to be much larger for detectors located in the southern hemisphere. In particular, if the CoGeNT detector were moved to e.g. Sierra Grande, Argentina then a 5σ dark matter discovery would be possible in around 30 days of operation.

  20. Cosmic strings in hidden sectors: 1. Radiation of standard model particles

    SciTech Connect

    Long, Andrew J.; Hyde, Jeffrey M.; Vachaspati, Tanmay E-mail: jmhyde@asu.edu

    2014-09-01

    In hidden sector models with an extra U(1) gauge group, new fields can interact with the Standard Model only through gauge kinetic mixing and the Higgs portal. After the U(1) is spontaneously broken, these interactions couple the resultant cosmic strings to Standard Model particles. We calculate the spectrum of radiation emitted by these ''dark strings'' in the form of Higgs bosons, Z bosons, and Standard Model fermions assuming that string tension is above the TeV scale. We also calculate the scattering cross sections of Standard Model fermions on dark strings due to the Aharonov-Bohm interaction. These radiation and scattering calculations will be applied in a subsequent paper to study the cosmological evolution and observational signatures of dark strings.

  1. Venus Express en route to probe the planet's hidden mysteries

    NASA Astrophysics Data System (ADS)

    2005-11-01

    Venus Express will eventually manoeuvre itself into orbit around Venus in order to perform a detailed study of the structure, chemistry and dynamics of the planet's atmosphere, which is characterised by extremely high temperatures, very high atmospheric pressure, a huge greenhouse effect and as-yet inexplicable "super-rotation" which means that it speeds around the planet in just four days. The European spacecraft will also be the first orbiter to probe the planet's surface while exploiting the "visibility windows" recently discovered in the infrared waveband. The 1240 kg mass spacecraft was developed for ESA by a European industrial team led by EADS Astrium with 25 main contractors spread across 14 countries. It lifted off onboard a Soyuz-Fregat rocket, the launch service being provided by Starsem. The lift-off from the Baikonur Cosmodrome in Kazakstan this morning took place at 09:33 hours local time (04:33 Central European Time). Initial Fregat upper-stage ignition took place 9 minutes into the flight, manoeuvring the spacecraft into a low-earth parking orbit. A second firing, 1 hour 22 minutes later, boosted the spacecraft to pursue its interplanetary trajectory. Contact with Venus Express was established by ESA's European Space Operations Centre (ESOC) at Darmstadt, Germany approximately two hours after lift-off. The spacecraft has correctly oriented itself in relation to the sun and has deployed its solar arrays. All onboard systems are operating perfectly and the orbiter is communicating with the Earth via its low-gain antenna. In three days' time, it will establish communications using its high-gain antenna. Full speed ahead for Venus Venus Express is currently distancing itself from the Earth full speed, heading on its five-month 350 million kilometre journey inside our solar system. After check-outs to ensure that its onboard equipment and instrument payload are in proper working order, the spacecraft will be mothballed, with contact with the Earth being

  2. Mirror world and superstring-inspired hidden sector of the Universe, dark matter and dark energy

    NASA Astrophysics Data System (ADS)

    Das, C. R.; Laperashvili, L. V.; Nielsen, H. B.; Tureanu, A.

    2011-09-01

    We develop a concept of parallel existence of the ordinary (O) and hidden (H) worlds. We compare two cases: (1) when the hidden sector of the Universe is a mirror counterpart of the ordinary world, and (2) when it is a superstring-inspired shadow world described, in contrast to the mirror world, by a symmetry group (or by a chain of groups), which does not coincide with the ordinary world symmetry group. We construct a cosmological model assuming the existence of the superstring-inspired E6 unification, broken at the early stage of the Universe to SO(10)×U(1)Z—in the O-world, and to SU(6)'×SU(2)θ'—in the H-world. As a result, we obtain the low-energy symmetry group GSM'×SU(2)θ' in the shadow world, instead of the standard model group GSM existing in the O-world. The additional non-Abelian SU(2)θ' group with massless gauge fields, ”thetons,” is responsible for dark energy. Considering a quintessence model of cosmology with an inflaton σ and an axion aθ, which is a pseudo Nambu-Goldstone boson induced by the SU(2)θ'-group anomaly, we explain the origin of dark energy, dark matter and ordinary matter. In the present model we review all cosmological epochs (inflation, reheating, recombination and nucleosynthesis), and give our version of the baryogenesis. The cosmological constant problem is also briefly discussed.

  3. Mass spectra of four-quark states in the hidden charm sector

    NASA Astrophysics Data System (ADS)

    Patel, Smruti; Shah, Manan; Vinodkumar, P. C.

    2014-08-01

    Masses of the low-lying four-quark states in the hidden charm sector ( are calculated within the framework of a non-relativistic quark model. The four-body system is considered as two two-body systems such as diquark-antidiquark ( - and quark-antiquark-quark-antiquark ( - q molecular-like four-quark states. Here, the Cornell-type potential has been used for describing the two-body interactions among Q - q , - , Q - , Qq - and Q - q , with appropriate string tensions. Our present analysis suggests the following exotic states: X(3823) , Z c(3900) , X(3915) , Z c(4025) , (4040) , Z 1(4050) and X(4160) as Q - q molecular-like four-quark states, while Z c(3885) , X(3940) and Y(4140) as the diquark-antidiquark four-quark states. We have been able to assign the JPC values for many of the recently observed exotic states according to their structure. Apart from this, we have identified the charged state Z(4430) recently confirmed by LHCb as the first radial excitation of Zc(3885) with G = + 1 and Y(4360) state as the first radial excitation of Y(4008) with G = - 1 and the state as the first radial excitation of the state.

  4. Fano resonance and the hidden order in URu2 Si 2 probed by quasiparticle scattering spectroscopy*

    NASA Astrophysics Data System (ADS)

    Park, W. K.; Greene, L. H.; Bauer, E. D.; Tobash, P. H.; Ronning, F.; Lu, X.; Sarrao, J. L.; Thompson, J. D.

    2011-03-01

    The nature of the hidden order transition occurring at 17.5 K in URu 2 Si 2 remains puzzling despite intensive investigations over the past two and half decades. Recent experimental and theoretical developments render it a timely subject to probe the hidden order state using quasiparticle tunneling and scattering techniques. We report on the Fano resonance in pure and Rh-doped URu 2 Si 2 single crystals using point-contact spectroscopy. The conductance spectra reproducibly reveal asymmetric double peak structures slightly off-centered around zero bias with the two peaks merging well above the hidden order transition temperature. An analysis using the Fano resonance model in a Kondo lattice [1] shows that the conductance peaks arise from the hybridization gap opening. Our estimated gap size agrees well with those reported from other measurements. We will present experimental results over a wide parameter space including temperature and doping dependences and discuss their underlying physics. M. Maltseva, M. Dzero, and P. Coleman, Phys. Rev. Lett. 103, 206402 (2009). * The work at UIUC is supported by the U.S. DOE under Award Nos. DE-FG02-07ER46453 and DE-AC02-98CH10886, and the work at LANL is carried out under the auspices of the U.S. DOE, Office of Science.

  5. Dynamically generated N* and {Lambda}* resonances in the hidden charm sector around 4.3 GeV

    SciTech Connect

    Wu Jiajun; Molina, R.; Oset, E.; Zou, B. S.

    2011-07-15

    The interactions of D-bar{Sigma}{sub c}-D-bar{Lambda}{sub c}, D-bar*{Sigma}{sub c}-D-bar*{Lambda}{sub c}, and related strangeness channels, are studied within the framework of the coupled-channel unitary approach with the local hidden gauge formalism. A series of meson-baryon dynamically generated relatively narrow N* and {Lambda}* resonances are predicted around 4.3 GeV in the hidden charm sector. We make estimates of production cross sections of these predicted resonances in p-barp collisions for the experiment of antiproton annihilation at Darmstadt (PANDA) at the forthcoming GSI Facility for Antiproton and Ion Research (FAIR) facility.

  6. Implications of heavy neutralino dark matter: The underlying structure in the hidden sector

    NASA Astrophysics Data System (ADS)

    Yoshimatsu, Nobuki

    2017-02-01

    The possibility of heavy neutralino dark matter (DM) in the gravity-mediation mechanism is explored. The appearance of the heavy lightest supersymmetric particle is seemingly suggested by Large Hadron Collider runs, which have not provided evidence of superparticles around the TeV region. On the basis of the so-called WIMPZILLA scenario, it is understood that the nonthermally produced DM has the larger mass than the reheating temperature. Hence, the expected DM mass should be more than 109 GeV so that thermal leptogenesis successfully occurs. In this paper, we first examine the generation of the Higgsino mass parameter (μ) in the context of gravity mediation, postulating that the resolution of the strong CP problem should be the criterion for arriving at a valid hypothesis for heavy neutralino DM. Accordingly, we address how the Peccei-Quinn (PQ) symmetry could influence dynamical supersymmetry breaking (DSB) models. It is found that as long as ΛSUSY (the SUSY-breaking scale) approximately coincides with ΛPQ (the PQ-breaking scale), no DSB models can naturally account for the existence of the heavy neutralino DM, based upon the supersymmetric Dine-Fischler-Srednicki-Zhitinitski (DFSZ)-like mechanism. Thus, we attempt to construct a new model wherein hierarchical SUSY breakings occur. For this purpose, we propose gauge coupling unification in the hidden-sector dynamics at some high-energy scale, and we show that such a class of models can achieve ΛSUSY ≫ ΛPQ through renormalization flow. As a consequence, the nonthermal neutralino, practically the wino-like one in our model, is shown to be a rather natural and viable DM candidate. Moreover, we argue that on the basis of Kac-Moody algebra, multiple breakdowns of supersymmetry may entail unified gauge dynamics. We also present a possible unified model. Finally, the heavy wino-like neutralino may be a DM candidate that will favor future direct DM detection experiments, mainly because its scattering on nuclei

  7. Photoacoustic imaging of hidden dental caries by using a fiber-based probing system

    NASA Astrophysics Data System (ADS)

    Koyama, Takuya; Kakino, Satoko; Matsuura, Yuji

    2017-04-01

    Photoacoustic method to detect hidden dental caries is proposed. It was found that high frequency ultrasonic waves are generated from hidden carious part when radiating laser light to occlusal surface of model tooth. By making a map of intensity of these high frequency components, photoacoustic images of hidden caries were successfully obtained. A photoacoustic imaging system using a bundle of hollow optical fiber was fabricated for using clinical application, and clear photoacoustic image of hidden caries was also obtained by this system.

  8. WIMPless dark matter from an anomaly-mediated supersymmetry breaking hidden sector with no new mass parameters

    NASA Astrophysics Data System (ADS)

    Feng, Jonathan L.; Rentala, Vikram; Surujon, Ze'Ev

    2012-03-01

    We present a model with dark matter in an anomaly-mediated supersymmetry breaking hidden sector with a U(1)×U(1) gauge symmetry. The symmetries of the model stabilize the dark matter and forbid the introduction of new mass parameters. As a result, the thermal relic density is completely determined by the gravitino mass and dimensionless couplings. Assuming nonhierarchical couplings, the thermal relic density is ΩX˜0.1, independent of the dark matter’s mass and interaction strength, realizing the WIMPless miracle. The model has several striking features. For particle physics, stability of the dark matter is completely consistent with R-parity violation in the visible sector, with implications for superpartner collider signatures; also the thermal relic’s mass may be ˜10GeV or lighter, which is of interest given recent direct detection results. Interesting astrophysical signatures are dark matter self-interactions through a long-range force, and massless hidden photons and fermions that contribute to the number of relativistic degrees of freedom at big bang nucleosynthesis and cosmic microwave background. The latter are particularly interesting, given current indications for extra degrees of freedom and near future results from the Planck observatory.

  9. Search for Hidden-Sector Bosons in B0→K*0μ+μ- Decays

    NASA Astrophysics Data System (ADS)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreassi, G.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; d'Argent, P.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Bellee, V.; Belloli, N.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Billoir, P.; Bird, T.; Birnkraut, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Braun, S.; Britsch, M.; Britton, T.; Brodzicka, J.; Brook, N. H.; Buchanan, E.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Campana, P.; Campora Perez, D.; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cassina, L.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cavallero, G.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chefdeville, M.; Chen, S.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dall'Occo, E.; Dalseno, J.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Simone, P.; Dean, C.-T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Demmer, M.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Di Ruscio, F.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dreimanis, K.; Dufour, L.; Dujany, G.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H. M.; Evans, T.; Falabella, A.; Färber, C.; Farley, N.; Farry, S.; Fay, R.; Ferguson, D.; Fernandez Albor, V.; Ferrari, F.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fohl, K.; Fol, P.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; García Pardiñas, J.; Garra Tico, J.; Garrido, L.; Gascon, D.; Gaspar, C.; Gauld, R.; Gavardi, L.; Gazzoni, G.; Gerick, D.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Gianı, S.; Gibson, V.; Girard, O. G.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gotti, C.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graverini, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadavizadeh, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Humair, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Karodia, S.; Kecke, M.; Kelsey, M.; Kenyon, I. R.; Kenzie, M.; Ketel, T.; Khairullin, E.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Klimaszewski, K.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Kozeiha, M.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Krzemien, W.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kuonen, A. K.; Kurek, K.; Kvaratskheliya, T.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Lemos Cid, E.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Likhomanenko, T.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Liu, X.; Loh, D.; Longstaff, I.; Lopes, J. H.; Lucchesi, D.; Lucio Martinez, M.; Luo, H.; Lupato, A.; Luppi, E.; Lupton, O.; Lusiani, A.; Machefert, F.; Maciuc, F.; Maev, O.; Maguire, K.; Malde, S.; Malinin, A.; Manca, G.; Mancinelli, G.; Manning, P.; Mapelli, A.; Maratas, J.; Marchand, J. F.; Marconi, U.; Marin Benito, C.; Marino, P.; Marks, J.; Martellotti, G.; Martin, M.; Martinelli, M.; Martinez Santos, D.; Martinez Vidal, F.; Martins Tostes, D.; Massafferri, A.; Matev, R.; Mathad, A.; Mathe, Z.; Matteuzzi, C.; Mauri, A.; Maurin, B.; Mazurov, A.; McCann, M.; McCarthy, J.; McNab, A.; McNulty, R.; Meadows, B.; Meier, F.; Meissner, M.; Melnychuk, D.; Merk, M.; Michielin, E.; Milanes, D. A.; Minard, M.-N.; Mitzel, D. S.; Molina Rodriguez, J.; Monroy, I. A.; Monteil, S.; Morandin, M.; Morawski, P.; Mordà, A.; Morello, M. J.; Moron, J.; Morris, A. B.; Mountain, R.; Muheim, F.; Müller, D.; Müller, J.; Müller, K.; Müller, V.; Mussini, M.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nandi, A.; Nasteva, I.; Needham, M.; Neri, N.; Neubert, S.; Neufeld, N.; Neuner, M.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Niess, V.; Niet, R.; Nikitin, N.; Nikodem, T.; Ninci, D.; Novoselov, A.; O'Hanlon, D. P.; Oblakowska-Mucha, A.; Obraztsov, V.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Onderwater, C. J. G.; Osorio Rodrigues, B.; Otalora Goicochea, J. M.; Otto, A.; Owen, P.; Oyanguren, A.; Palano, A.; Palombo, F.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Pappalardo, L. L.; Pappenheimer, C.; Parkes, C.; Passaleva, G.; Patel, G. D.; Patel, M.; Patrignani, C.; Pearce, A.; Pellegrino, A.; Penso, G.; Pepe Altarelli, M.; Perazzini, S.; Perret, P.; Pescatore, L.; Petridis, K.; Petrolini, A.; Petruzzo, M.; Picatoste Olloqui, E.; Pietrzyk, B.; Pilař, T.; Pinci, D.; Pistone, A.; Piucci, A.; Playfer, S.; Plo Casasus, M.; Poikela, T.; Polci, F.; Poluektov, A.; Polyakov, I.; Polycarpo, E.; Popov, A.; Popov, D.; Popovici, B.; Potterat, C.; Price, E.; Price, J. D.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Puig Navarro, A.; Punzi, G.; Qian, W.; Quagliani, R.; Rachwal, B.; Rademacker, J. H.; Rama, M.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Redi, F.; Reichert, S.; Reid, M. M.; dos Reis, A. C.; Ricciardi, S.; Richards, S.; Rihl, M.; Rinnert, K.; Rives Molina, V.; Robbe, P.; Rodrigues, A. B.; Rodrigues, E.; Rodriguez Lopez, J. A.; Rodriguez Perez, P.; Roiser, S.; Romanovsky, V.; Romero Vidal, A.; Ronayne, J. W.; Rotondo, M.; Rouvinet, J.; Ruf, T.; Ruiz Valls, P.; Saborido Silva, J. J.; Sagidova, N.; Sail, P.; Saitta, B.; Salustino Guimaraes, V.; Sanchez Mayordomo, C.; Sanmartin Sedes, B.; Santacesaria, R.; Santamarina Rios, C.; Santimaria, M.; Santovetti, E.; Sarti, A.; Satriano, C.; Satta, A.; Saunders, D. M.; Savrina, D.; Schiller, M.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmelzer, T.; Schmidt, B.; Schneider, O.; Schopper, A.; Schubiger, M.; Schune, M.-H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Semennikov, A.; Serra, N.; Serrano, J.; Sestini, L.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, V.; Shires, A.; Siddi, B. G.; Silva Coutinho, R.; Silva de Oliveira, L.; Simi, G.; Sirendi, M.; Skidmore, N.; Skillicorn, I.; Skwarnicki, T.; Smith, E.; Smith, E.; Smith, I. T.; Smith, J.; Smith, M.; Snoek, H.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; Souza, D.; Souza De Paula, B.; Spaan, B.; Spradlin, P.; Sridharan, S.; Stagni, F.; Stahl, M.; Stahl, S.; Stefkova, S.; Steinkamp, O.; Stenyakin, O.; Stevenson, S.; Stoica, S.; Stone, S.; Storaci, B.; Stracka, S.; Straticiuc, M.; Straumann, U.; Sun, L.; Sutcliffe, W.; Swientek, K.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szumlak, T.; T'Jampens, S.; Tayduganov, A.; Tekampe, T.; Teklishyn, M.; Tellarini, G.; Teubert, F.; Thomas, C.; Thomas, E.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Todd, J.; Tolk, S.; Tomassetti, L.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Trabelsi, K.; Tran, M. T.; Tresch, M.; Trisovic, A.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vacca, C.; Vagnoni, V.; Valenti, G.; Vallier, A.; Vazquez Gomez, R.; Vazquez Regueiro, P.; Vázquez Sierra, C.; Vecchi, S.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vieites Diaz, M.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; de Vries, J. A.; Waldi, R.; Wallace, C.; Wallace, R.; Walsh, J.; Wandernoth, S.; Wang, J.; Ward, D. R.; Watson, N. K.; Websdale, D.; Weiden, A.; Whitehead, M.; Wilkinson, G.; Wilkinson, M.; Williams, M.; Williams, M. P.; Williams, M.; Williams, T.; Wilson, F. F.; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wright, S.; Wyllie, K.; Xie, Y.; Xu, Z.; Yang, Z.; Yu, J.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, L.; Zhang, Y.; Zhelezov, A.; Zhokhov, A.; Zhong, L.; Zucchelli, S.; LHCb Collaboration

    2015-10-01

    A search is presented for hidden-sector bosons, χ , produced in the decay B0→K*(892 )0χ , with K*(892 )0→K+π- and χ →μ+μ-. The search is performed using p p -collision data corresponding to 3.0 fb-1 collected with the LHCb detector. No significant signal is observed in the accessible mass range 214 ≤m (χ )≤4350 MeV , and upper limits are placed on the branching fraction product B (B0→K*(892 )0χ )×B (χ →μ+μ-) as a function of the mass and lifetime of the χ boson. These limits are of the order of 1 0-9 for χ lifetimes less than 100 ps over most of the m (χ ) range, and place the most stringent constraints to date on many theories that predict the existence of additional low-mass bosons.

  10. Revisiting scalar quark hidden sector in light of 750-GeV diphoton resonance

    NASA Astrophysics Data System (ADS)

    Chiang, Cheng-Wei; Ibe, Masahiro; Yanagida, Tsutomu T.

    2016-05-01

    We revisit the model of a CP -even singlet scalar resonance proposed in arXiv:1507.02483 , where the resonance appears as the lightest composite state made of scalar quarks participating in hidden strong dynamics. We show that the model can consistently explain the excess of diphoton events with an invariant mass around 750 GeV reported by both the ATLAS and CMS experiments. We also discuss the nature of the charged composite states in the TeV range which accompany to the neutral scalar. Due to inseparability of the dynamical scale and the mass of the resonance, the model also predicts signatures associated with the hidden dynamics such as leptons, jets along with multiple photons at future collider experiments. We also associate the TeV-scale dynamics behind the resonance with an explanation of dark matter.

  11. Visible and hidden sectors in a model with Maxwell and Chern-Simons gauge dynamics

    NASA Astrophysics Data System (ADS)

    Ireson, Edwin; Schaposnik, Fidel A.; Tallarita, Gianni

    2016-11-01

    We study a U(1) × U(1) gauge theory discussing its vortex solutions and supersymmetric extension. In our set-up, the dynamics of one of two Abelian gauge fields is governed by a Maxwell term, the other by a Chern-Simons term. The two sectors interact via a BF gauge field mixing and a Higgs portal term that connects the two complex scalars. We also consider the supersymmetric version of this system which allows to find for the bosonic sector BPS equations in which an additional real scalar field enters into play. We study numerically the field equations finding vortex solutions with both magnetic flux and electric charge.

  12. Muon beam experiments to probe the dark sector

    NASA Astrophysics Data System (ADS)

    Chen, Chien-Yi; Pospelov, Maxim; Zhong, Yi-Ming

    2017-06-01

    A persistence of several anomalies in muon physics, such as the muon anomalous magnetic moment and the muonic hydrogen Lamb shift, hints at new light particles beyond the Standard Model. We address a subset of these models that have a new light scalar state with sizable couplings to muons and suppressed couplings to electrons. A novel way to search for such particles would be through muon beam-dump experiments by (1) missing momentum searches; (2) searches for decays with displaced vertices. The muon beams available at CERN and Fermilab present attractive opportunities for exploring the new scalar with a mass below the dimuon threshold, and potentially covering a range of relevant candidate models. For the models considered in this paper, both types of signals, muon missing momentum and anomalous energy deposition at a distance, can probe a substantial fraction of the unexplored parameter space of the new light scalar, including a region that can explain the muon anomalous magnetic moment discrepancy.

  13. Black hole portal into hidden valleys

    NASA Astrophysics Data System (ADS)

    Dubovsky, Sergei; Gorbenko, Victor

    2011-05-01

    Superradiant instability turns rotating astrophysical black holes into unique probes of light axions. We consider what happens when a light axion is coupled to a strongly coupled hidden gauge sector. In this case superradiance results in an adiabatic increase of a hidden sector CP-violating θ parameter in a near horizon region. This may trigger a first order phase transition in the gauge sector. As a result a significant fraction of a black hole mass is released as a cloud of hidden mesons and can be later converted into electromagnetic radiation. This results in a violent electromagnetic burst. The characteristic frequency of such bursts may range from ˜100eV to ˜100MeV.

  14. Probing the Dark Sector with Dark Matter Bound States.

    PubMed

    An, Haipeng; Echenard, Bertrand; Pospelov, Maxim; Zhang, Yue

    2016-04-15

    A model of the dark sector where O(few  GeV) mass dark matter particles χ couple to a lighter dark force mediator V, m_{V}≪m_{χ}, is motivated by the recently discovered mismatch between simulated and observed shapes of galactic halos. Such models, in general, provide a challenge for direct detection efforts and collider searches. We show that for a large range of coupling constants and masses, the production and decay of the bound states of χ, such as 0^{-+} and 1^{--} states, η_{D} and ϒ_{D}, is an important search channel. We show that e^{+}e^{-}→η_{D}+V or ϒ_{D}+γ production at B factories for α_{D}>0.1 is sufficiently strong to result in multiple pairs of charged leptons and pions via η_{D}→2V→2(l^{+}l^{-}) and ϒ_{D}→3V→3(l^{+}l^{-}) (l=e,μ,π). The absence of such final states in the existing searches performed at BABAR and Belle sets new constraints on the parameter space of the model. We also show that a search for multiple bremsstrahlung of dark force mediators, e^{+}e^{-}→χχ[over ¯]+nV, resulting in missing energy and multiple leptons, will further improve the sensitivity to self-interacting dark matter.

  15. Probing the Dark Sector with Dark Matter Bound States

    NASA Astrophysics Data System (ADS)

    An, Haipeng; Echenard, Bertrand; Pospelov, Maxim; Zhang, Yue

    2016-04-01

    A model of the dark sector where O (few GeV ) mass dark matter particles χ couple to a lighter dark force mediator V , mV≪mχ, is motivated by the recently discovered mismatch between simulated and observed shapes of galactic halos. Such models, in general, provide a challenge for direct detection efforts and collider searches. We show that for a large range of coupling constants and masses, the production and decay of the bound states of χ , such as 0-+ and 1-- states, ηD and ϒD, is an important search channel. We show that e+e-→ηD+V or ϒD+γ production at B factories for αD>0.1 is sufficiently strong to result in multiple pairs of charged leptons and pions via ηD→2 V →2 (l+l-) and ϒD→3 V →3 (l+l-) (l =e ,μ ,π ). The absence of such final states in the existing searches performed at BABAR and Belle sets new constraints on the parameter space of the model. We also show that a search for multiple bremsstrahlung of dark force mediators, e+e-→χ χ ¯+n V , resulting in missing energy and multiple leptons, will further improve the sensitivity to self-interacting dark matter.

  16. Hidden sector hydrogen as dark matter: Small-scale structure formation predictions and the importance of hyperfine interactions

    NASA Astrophysics Data System (ADS)

    Boddy, Kimberly K.; Kaplinghat, Manoj; Kwa, Anna; Peter, Annika H. G.

    2016-12-01

    We study the atomic physics and the astrophysical implications of a model in which the dark matter is the analog of hydrogen in a secluded sector. The self-interactions between dark matter particles include both elastic scatterings as well as inelastic processes due to a hyperfine transition. The self-interaction cross sections are computed by numerically solving the coupled Schrödinger equations for this system. We show that these self-interactions exhibit the right velocity dependence to explain the low dark matter density cores seen in small galaxies while being consistent with all constraints from observations of clusters of galaxies. For a viable solution, the dark hydrogen mass has to be in the 10-100 GeV range and the dark fine-structure constant has to be larger than 0.01. This range of model parameters requires the existence of a dark matter-antimatter asymmetry in the early universe to set the relic abundance of dark matter. For this range of parameters, we show that significant cooling losses may occur due to inelastic excitations to the hyperfine state and subsequent decays, with implications for the evolution of low-mass halos and the early growth of supermassive black holes. Cooling from excitations to higher n levels of dark hydrogen and subsequent decays is possible at the cluster scale, with a strong dependence on halo mass. Finally, we show that the minimum halo mass is in the range of 1 03.5 to 1 07M⊙ for the viable regions of parameter space, significantly larger than the typical predictions for weakly interacting dark matter models. This pattern of observables in cosmological structure formation is unique to this model, making it possible to rule in or rule out hidden sector hydrogen as a viable dark matter model.

  17. Search for Hidden-Sector Bosons in B(0)→K(*0)μ(+)μ(-) Decays.

    PubMed

    Aaij, R; Adeva, B; Adinolfi, M; Affolder, A; Ajaltouni, Z; Akar, S; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; An, L; Anderlini, L; Anderson, J; Andreassi, G; Andreotti, M; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; d'Argent, P; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Badalov, A; Baesso, C; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Batozskaya, V; Battista, V; Bay, A; Beaucourt, L; Beddow, J; Bedeschi, F; Bediaga, I; Bel, L J; Bellee, V; Belloli, N; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bertolin, A; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Billoir, P; Bird, T; Birnkraut, A; Bizzeti, A; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borsato, M; Bowcock, T J V; Bowen, E; Bozzi, C; Braun, S; Britsch, M; Britton, T; Brodzicka, J; Brook, N H; Buchanan, E; Bursche, A; Buytaert, J; Cadeddu, S; Calabrese, R; Calvi, M; Calvo Gomez, M; Campana, P; Campora Perez, D; Capriotti, L; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carniti, P; Carson, L; Carvalho Akiba, K; Casse, G; Cassina, L; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cavallero, G; Cenci, R; Charles, M; Charpentier, Ph; Chefdeville, M; Chen, S; Cheung, S-F; Chiapolini, N; Chrzaszcz, M; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coco, V; Cogan, J; Cogneras, E; Cogoni, V; Cojocariu, L; Collazuol, G; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Corvo, M; Couturier, B; Cowan, G A; Craik, D C; Crocombe, A; Cruz Torres, M; Cunliffe, S; Currie, R; D'Ambrosio, C; Dall'Occo, E; Dalseno, J; David, P N Y; Davis, A; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Simone, P; Dean, C-T; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Demmer, M; Derkach, D; Deschamps, O; Dettori, F; Dey, B; Di Canto, A; Di Ruscio, F; Dijkstra, H; Donleavy, S; Dordei, F; Dorigo, M; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dreimanis, K; Dufour, L; Dujany, G; Dupertuis, F; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Ely, S; Esen, S; Evans, H M; Evans, T; Falabella, A; Färber, C; Farley, N; Farry, S; Fay, R; Ferguson, D; Fernandez Albor, V; Ferrari, F; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fiorini, M; Firlej, M; Fitzpatrick, C; Fiutowski, T; Fohl, K; Fol, P; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Fu, J; Furfaro, E; Gallas Torreira, A; Galli, D; Gallorini, S; Gambetta, S; Gandelman, M; Gandini, P; Gao, Y; García Pardiñas, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gauld, R; Gavardi, L; Gazzoni, G; Gerick, D; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gianelle, A; Gianì, S; Gibson, V; Girard, O G; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gotti, C; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graverini, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grillo, L; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadavizadeh, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hamilton, B; Han, X; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Henry, L; Hernando Morata, J A; van Herwijnen, E; Heß, M; Hicheur, A; Hill, D; Hoballah, M; Hombach, C; Hulsbergen, W; Humair, T; Hussain, N; Hutchcroft, D; Hynds, D; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jalocha, J; Jans, E; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Karodia, S; Kecke, M; Kelsey, M; Kenyon, I R; Kenzie, M; Ketel, T; Khairullin, E; Khanji, B; Khurewathanakul, C; Klaver, S; Klimaszewski, K; Kochebina, O; Kolpin, M; Komarov, I; Koopman, R F; Koppenburg, P; Kozeiha, M; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Krzemien, W; Kucewicz, W; Kucharczyk, M; Kudryavtsev, V; Kuonen, A K; Kurek, K; Kvaratskheliya, T; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lanfranchi, G; Langenbruch, C; Langhans, B; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Lemos Cid, E; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Likhomanenko, T; Liles, M; Lindner, R; Linn, C; Lionetto, F; Liu, B; Liu, X; Loh, D; Longstaff, I; Lopes, J H; Lucchesi, D; Lucio Martinez, M; Luo, H; Lupato, A; Luppi, E; Lupton, O; Lusiani, A; Machefert, F; Maciuc, F; Maev, O; Maguire, K; Malde, S; Malinin, A; Manca, G; Mancinelli, G; Manning, P; Mapelli, A; Maratas, J; Marchand, J F; Marconi, U; Marin Benito, C; Marino, P; Marks, J; Martellotti, G; Martin, M; Martinelli, M; Martinez Santos, D; Martinez Vidal, F; Martins Tostes, D; Massafferri, A; Matev, R; Mathad, A; Mathe, Z; Matteuzzi, C; Mauri, A; Maurin, B; Mazurov, A; McCann, M; McCarthy, J; McNab, A; McNulty, R; Meadows, B; Meier, F; Meissner, M; Melnychuk, D; Merk, M; Michielin, E; Milanes, D A; Minard, M-N; Mitzel, D S; Molina Rodriguez, J; Monroy, I A; Monteil, S; Morandin, M; Morawski, P; Mordà, A; Morello, M J; Moron, J; Morris, A B; Mountain, R; Muheim, F; Müller, D; Müller, J; Müller, K; Müller, V; Mussini, M; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nandi, A; Nasteva, I; Needham, M; Neri, N; Neubert, S; Neufeld, N; Neuner, M; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Ninci, D; Novoselov, A; O'Hanlon, D P; Oblakowska-Mucha, A; Obraztsov, V; Ogilvy, S; Okhrimenko, O; Oldeman, R; Onderwater, C J G; Osorio Rodrigues, B; Otalora Goicochea, J M; Otto, A; Owen, P; Oyanguren, A; Palano, A; Palombo, F; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Pappalardo, L L; Pappenheimer, C; Parkes, C; Passaleva, G; Patel, G D; Patel, M; Patrignani, C; Pearce, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perret, P; Pescatore, L; Petridis, K; Petrolini, A; Petruzzo, M; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Pistone, A; Piucci, A; Playfer, S; Plo Casasus, M; Poikela, T; Polci, F; Poluektov, A; Polyakov, I; Polycarpo, E; Popov, A; Popov, D; Popovici, B; Potterat, C; Price, E; Price, J D; Prisciandaro, J; Pritchard, A; Prouve, C; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Quagliani, R; Rachwal, B; Rademacker, J H; Rama, M; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redi, F; Reichert, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, S; Rihl, M; Rinnert, K; Rives Molina, V; Robbe, P; Rodrigues, A B; Rodrigues, E; Rodriguez Lopez, J A; Rodriguez Perez, P; Roiser, S; Romanovsky, V; Romero Vidal, A; Ronayne, J W; Rotondo, M; Rouvinet, J; Ruf, T; Ruiz Valls, P; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salustino Guimaraes, V; Sanchez Mayordomo, C; Sanmartin Sedes, B; Santacesaria, R; Santamarina Rios, C; Santimaria, M; Santovetti, E; Sarti, A; Satriano, C; Satta, A; Saunders, D M; Savrina, D; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmelzer, T; Schmidt, B; Schneider, O; Schopper, A; Schubiger, M; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Semennikov, A; Serra, N; Serrano, J; Sestini, L; Seyfert, P; Shapkin, M; Shapoval, I; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, V; Shires, A; Siddi, B G; Silva Coutinho, R; Silva de Oliveira, L; Simi, G; Sirendi, M; Skidmore, N; Skillicorn, I; Skwarnicki, T; Smith, E; Smith, E; Smith, I T; Smith, J; Smith, M; Snoek, H; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Spradlin, P; Sridharan, S; Stagni, F; Stahl, M; Stahl, S; Stefkova, S; Steinkamp, O; Stenyakin, O; Stevenson, S; Stoica, S; Stone, S; Storaci, B; Stracka, S; Straticiuc, M; Straumann, U; Sun, L; Sutcliffe, W; Swientek, K; Swientek, S; Syropoulos, V; Szczekowski, M; Szumlak, T; T'Jampens, S; Tayduganov, A; Tekampe, T; Teklishyn, M; Tellarini, G; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Todd, J; Tolk, S; Tomassetti, L; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Trabelsi, K; Tran, M T; Tresch, M; Trisovic, A; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ukleja, A; Ustyuzhanin, A; Uwer, U; Vacca, C; Vagnoni, V; Valenti, G; Vallier, A; Vazquez Gomez, R; Vazquez Regueiro, P; Vázquez Sierra, C; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vieites Diaz, M; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; de Vries, J A; Waldi, R; Wallace, C; Wallace, R; Walsh, J; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Websdale, D; Weiden, A; Whitehead, M; Wilkinson, G; Wilkinson, M; Williams, M; Williams, M P; Williams, M; Williams, T; Wilson, F F; Wimberley, J; Wishahi, J; Wislicki, W; Witek, M; Wormser, G; Wotton, S A; Wright, S; Wyllie, K; Xie, Y; Xu, Z; Yang, Z; Yu, J; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, L; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L; Zucchelli, S

    2015-10-16

    A search is presented for hidden-sector bosons, χ, produced in the decay B(0)→K*(892)(0)χ, with K*(892)(0)→K(+)π(-) and χ→μ(+)μ(-). The search is performed using pp-collision data corresponding to 3.0  fb(-1) collected with the LHCb detector. No significant signal is observed in the accessible mass range 214≤m(χ)≤4350  MeV, and upper limits are placed on the branching fraction product B(B(0)→K*(892)(0)χ)×B(χ→μ(+)μ(-)) as a function of the mass and lifetime of the χ boson. These limits are of the order of 10(-9) for χ lifetimes less than 100 ps over most of the m(χ) range, and place the most stringent constraints to date on many theories that predict the existence of additional low-mass bosons.

  18. Hidden Sector Hydrogen as Dark Matter: Predictions for Small-scale Structure

    NASA Astrophysics Data System (ADS)

    Kwa, Anna; Boddy, Kimberly; Kaplinghat, Manoj; Peter, Annika

    2017-01-01

    I will discuss the atomic physics and the astrophysical implications of a model in which the dark matter is the analog of hydrogen in a secluded sector. The self interactions between dark matter particles include both elastic scatterings as well as inelastic processes due to a hyperfine transition. The self-interaction cross sections are computed by numerically solving the coupled Schrodinger equations for this system. The velocity-dependence of the self-interaction cross sections produces the low dark matter density cores seen in spiral galaxies while maintaining consistency with constraints from observations of galaxy clusters. Significant cooling losses may occur due to inelastic excitations to the hyperfine state and subsequent decays (up to about 10% of the collisional heating rate) in this region of parameter space, with implications for the evolution of low mass halos and early growth of black holes. Finally, the minimum halo mass is in the range of 103 to 107 solar masses for viable regions of parameter space, which is significantly larger than the typical predictions for weakly-interacting dark matter models.

  19. Galactic center γ-ray excess in hidden sector DM models with dark gauge symmetries: local Z{sub 3} symmetry as an example

    SciTech Connect

    Ko, P.; Tang, Yong E-mail: ytang@kias.re.kr

    2015-01-01

    We show that hidden sector dark matter (DM) models with local dark gauge symmetries make a natural playground for the possible γ-ray excess from the galactic center (GC). We first discuss in detail the GC γ-ray excess in a scalar dark matter (DM) model with local Z{sub 3} symmetry which was recently proposed by the present authors. Within this model, scalar DM with mass 30–70 GeV is allowed due to the newly-opened (semi-)annihilation channels of a DM pair into dark Higgs φ and/or dark photon Z' pair, and the γ-ray spectrum from the GC can be fit within this model. Then we argue that the GC gamma ray excess can be easily accommodated within hidden sector dark matter models where DM is stabilized by local gauge symmetries, due to the presence of dark Higgs (and also dark photon for Abelian dark gauge symmetry)

  20. Galactic center γ-ray excess in hidden sector DM models with dark gauge symmetries: local Z{sub 3} symmetry as an example

    SciTech Connect

    Ko, P.; Tang, Yong

    2015-01-16

    We show that hidden sector dark matter (DM) models with local dark gauge symmetries make a natural playground for the possible γ-ray excess from the galactic center (GC). We first discuss in detail the GC γ-ray excess in a scalar dark matter (DM) model with local Z{sub 3} symmetry which was recently proposed by the present authors. Within this model, scalar DM with mass 30–70 GeV is allowed due to the newly-opened (semi-)annihilation channels of a DM pair into dark Higgs ϕ and/or dark photon Z′ pair, and the γ-ray spectrum from the GC can be fit within this model. Then we argue that the GC gamma ray excess can be easily accommodated within hidden sector dark matter models where DM is stabilized by local gauge symmetries, due to the presence of dark Higgs (and also dark photon for Abelian dark gauge symmetry)

  1. Probing a new strongly interacting sector via composite diboson resonances

    NASA Astrophysics Data System (ADS)

    Ko, P.; Yu, Chaehyun; Yuan, Tzu-Chiang

    2017-06-01

    Diphoton resonance was a crucial discovery mode for the 125 GeV Standard Model Higgs boson at the Large Hadron Collider (LHC). This mode or the more general diboson modes may also play an important role in probing for new physics beyond the Standard Model. In this paper, we consider the possibility that a diphoton resonance is due to a composite scalar or pseudoscalar boson, whose constituents are either new hyperquarks Q or scalar hyperquarks Q ˜ confined by a new hypercolor force at a confinement scale Λh. Assuming the mass mQ (or mQ ˜) ≫Λh, a diphoton resonance could be interpreted as either a Q Q ¯ (1S0) state ηQ with JP C=0-+ or a Q ˜ Q˜ †(1S0) state ηQ ˜ with JP C=0++. For the Q Q ¯ scenario, there will be a spin-triplet partner ψQ which is slightly heavier than ηQ due to the hyperfine interactions mediated by hypercolor gluon exchange; while for the Q ˜Q˜† scenario, the spin-triplet partner χQ ˜ arises from higher radial excitation with nonzero orbital angular momentum. We consider productions and decays of ηQ, ηQ ˜, ψQ, and χQ ˜ at the LHC using the nonrelativistic QCD factorization approach. We discuss how to test these scenarios by using the Drell-Yan process and the forward dijet azimuthal angular distributions to determine the JP C quantum number of the diphoton resonance. Constraints on the parameter space can be obtained by interpreting some of the small diphoton "excesses" reported by the LHC as the composite scalar or pseudoscalar of the model. Another important test of the model is the presence of a nearby hypercolor-singlet but color-octet state like the 1S0 state ηQ8 or ηQ˜8, which can also be constrained by dijet or monojet plus monophoton data. Both possibilities of a large or small width of the resonance can be accommodated, depending on whether the hyper-glueball states are kinematically allowed in the final state or not.

  2. A general holographic insulator/superconductor model with dark matter sector away from the probe limit

    NASA Astrophysics Data System (ADS)

    Peng, Yan; Pan, Qiyuan; Liu, Yunqi

    2017-02-01

    We investigate holographic phase transitions with dark matter sector in the AdS soliton background away from the probe limit. In cases of weak backreaction, we find that the larger coupling parameter α makes the gap of condensation shallower and the critical chemical potential keeps as a constant. In contrast, for very heavy backreaction, the dark matter sector could affect the critical chemical potential and the order of phase transitions. We also find the jump of the holographic topological entanglement entropy corresponds to a first order transition between superconducting states in this model with dark matter sector. More importantly, for certain sets of parameters, we observe novel phenomenon of retrograde condensation. In a word, the dark matter sector provides richer physics in the phase structure and the holographic superconductor properties are helpful in understanding dark matter.

  3. Selective Probing of Hidden Spin-Polarized States in Inversion-Symmetric Bulk MoS2

    NASA Astrophysics Data System (ADS)

    Razzoli, E.; Jaouen, T.; Mottas, M.-L.; Hildebrand, B.; Monney, G.; Pisoni, A.; Muff, S.; Fanciulli, M.; Plumb, N. C.; Rogalev, V. A.; Strocov, V. N.; Mesot, J.; Shi, M.; Dil, J. H.; Beck, H.; Aebi, P.

    2017-02-01

    Spin- and angle-resolved photoemission spectroscopy is used to reveal that a large spin polarization is observable in the bulk centrosymmetric transition metal dichalcogenide MoS2 . It is found that the measured spin polarization can be reversed by changing the handedness of incident circularly polarized light. Calculations based on a three-step model of photoemission show that the valley and layer-locked spin-polarized electronic states can be selectively addressed by circularly polarized light, therefore providing a novel route to probe these hidden spin-polarized states in inversion-symmetric systems as predicted by Zhang et al. [Nat. Phys. 10, 387 (2014)., 10.1038/nphys2933].

  4. A framework to analyze searches for gauge bosons of the hidden light sector in electron scattering fixed target experiments

    SciTech Connect

    Beranek, T.

    2013-11-07

    Electron scattering fixed target experiments are a versatile tool to probe various kinds of physics phenomena. Recently fixed target experiments in which an electron beam is scattered off a heavy nucleus and a lepton-antilepton pair is created, i.e. e(A,Z) →e(A,Z)l{sup +}l{sup −}, were utilized to search for physics beyond the standard model at modest energies. In these experiments one searches for a small, narrow resonance in the invariant mass spectrum of the lepton-antilepton pair, arising from the exchange of a new light gauge boson γ′ coupling to the dark sector as well as very weakly to standard model particles. Such a signal would appear as an enhancement over a smooth QED background. Hence a precise understanding of the background is crucial. We present a theoretical analysis of the process e(A,Z) →e(A,Z)l{sup +}l{sup −}. Therefore we have performed an analysis of the cross section, which is then used to extract exclusion limits on the parameter space of the γ′, describing the existing experimental data taken at MAMI.

  5. OH as a Probe of The Milky Way's Hidden Gas: First Results from SPLASH

    NASA Astrophysics Data System (ADS)

    Dawson, J. R.; Walsh, A. J.

    SPLASH (the Southern Parkes Large-Area Survey in Hydroxyl) is a deep survey of ground-state OH absorption and emission from the Galactic Plane, as well as an unbiased search for OH masers. Key early results include the detection of a rich and complex distribution of diffuse, optically thin OH with strongly non-thermal excitation temperatures, and the detection of numerous new maser sources. The survey aims to use OH as a probe of CO-dark H2 ISM Galactic scales, with future plans including comprehensive comparisons with CO and Hi, as well as non-LTE excitation modelling of the four ground-state lines.

  6. OH as a Probe of the Milky Way's Hidden Gas - First Results From SPLASH

    NASA Astrophysics Data System (ADS)

    Dawson, Joanne

    2015-08-01

    In recent years it has become increasingly clear that "standard" radio line tracers of the interstellar medium fail to account for a substantial fraction of the neutral gas in star-forming galaxies. This transition-state gas bridges the regimes that can be effectively traced by CO and HI, representing an intermediate stage in the evolutionary sequence linking atomic gas and star-forming molecular clouds. The 18 cm ground state transitions of OH are a promising probe of this material. I will present first results from SPLASH - the Southern Parkes Large-Area Survey in Hydroxyl - a sensitive, unbiased and fully-sampled survey of the Southern Galactic Plane and Galactic Centre in all four ground-state transitions of OH. The survey is a deep census of 1612, 1665, 1667 and 1720 MHz OH absorption and emission from the Galactic molecular ISM, as well as an unbiased search for maser sources in these transitions. Key early results include the detection of a rich and complex distribution of diffuse, optically thin OH with strongly non-thermal excitation temperatures, and the detection of numerous new maser sources from both evolved stars and young star-forming regions. I will outline future plans for comprehensive comparisons with HI and CO which aim to utilise OH as a probe of the transition-state ISM Galactic scales.

  7. Hidden photons in connection to dark matter

    NASA Astrophysics Data System (ADS)

    Andreas, Sarah; Goodsell, Mark D.; Ringwald, Andreas

    2013-11-01

    Light extra U(1) gauge bosons, so called hidden photons, which reside in a hidden sector have attracted much attention since they are a well motivated feature of many scenarios beyond the Standard Model and furthermore could mediate the interaction with hidden sector dark matter. We review limits on hidden photons from past electron beam dump experiments including two new limits from such experiments at KEK and Orsay. In addition, we study the possibility of having dark matter in the hidden sector. A simple toy model and different supersymmetric realisations are shown to provide viable dark matter candidates in the hidden sector that are in agreement with recent direct detection limits.

  8. Strategies for probing nonminimal dark sectors at colliders: The interplay between cuts and kinematic distributions

    NASA Astrophysics Data System (ADS)

    Dienes, Keith R.; Su, Shufang; Thomas, Brooks

    2015-03-01

    In this paper, we examine the strategies and prospects for distinguishing between traditional dark-matter models and models with nonminimal dark sectors—including models of Dynamical Dark Matter—at hadron colliders. For concreteness, we focus on events with two hadronic jets and large missing transverse energy at the Large Hadron Collider (LHC). As we discuss, simple "bump-hunting" searches are not sufficient; probing nonminimal dark sectors typically requires an analysis of the actual shapes of the distributions of relevant kinematic variables. We therefore begin by identifying those kinematic variables whose distributions are particularly suited to this task. However, as we demonstrate, this then leads to a number of additional subtleties, since cuts imposed on the data for the purpose of background reduction can at the same time have the unintended consequence of distorting these distributions in unexpected ways, thereby obscuring signals of new physics. We therefore proceed to study the correlations between several of the most popular relevant kinematic variables currently on the market, and investigate how imposing cuts on one or more of these variables can impact the distributions of others. Finally, we combine our results in order to assess the prospects for distinguishing nonminimal dark sectors in this channel at the upgraded LHC.

  9. Second harmonic poloidal waves observed by Van Allen Probes in the dusk-midnight sector

    NASA Astrophysics Data System (ADS)

    Min, Kyungguk; Takahashi, Kazue; Ukhorskiy, Aleksandr Y.; Manweiler, Jerry W.; Spence, Harlan E.; Singer, Howard, J.; Claudepierre, Seth G.; Larsen, Brian A.; Soto-Chavez, A. Rualdo; Cohen, Ross J.

    2017-03-01

    This paper presents observations of ultralow-frequency (ULF) waves from Van Allen Probes. The event that generated the ULF waves occurred 2 days after a minor geomagnetic storm during a geomagnetically quiet time. Narrowband pulsations with a frequency of about 7 mHz with moderate amplitudes were registered in the premidnight sector when Probe A was passing through an enhanced density region near geosynchronous orbit. Probe B, which passed through the region earlier, did not detect the narrowband pulsations but only broadband noise. Despite the single-spacecraft measurements, we were able to determine various wave properties. We find that (1) the observed waves are a second harmonic poloidal mode propagating westward with an azimuthal wave number estimated to be ˜100; (2) the magnetic field fluctuations have a finite compressional component due to small but finite plasma beta (˜0.1); (3) the energetic proton fluxes in the energy ranging from above 10 keV to about 100 keV exhibit pulsations with the same frequency as the poloidal mode and energy-dependent phase delays relative to the azimuthal component of the electric field, providing evidence for drift-bounce resonance; and (4) the second harmonic poloidal mode may have been excited via the drift-bounce resonance mechanism with free energy fed by the inward radial gradient of ˜80 keV protons. We show that the wave active region is where the plume overlaps the outer edge of ring current and suggest that this region can have a wide longitudinal extent near geosynchronous orbit.

  10. Probing the Higgs sector of high-scale supersymmetry-breaking models at the Tevatron.

    SciTech Connect

    Carena, M.; Draper, P.; Heinemeyer, S.; Liu, T.; Wagner, C. E. M.; Weiglein, G.

    2011-03-07

    A canonical signature of the minimal supersymmetric standard model (MSSM) is the presence of a neutral Higgs boson with mass bounded from above by about 135 GeV and standard model (SM)-like couplings to the electroweak gauge bosons. In this paper we investigate the reach of the Tevatron collider for the MSSM Higgs sector parameter space associated with a variety of high-scale minimal models of supersymmetry (SUSY) breaking, including the constrained MSSM, minimal gauge-mediated SUSY breaking, and minimal anomaly-mediated SUSY breaking. We find that the Tevatron can provide strong constraints on these models via Higgs boson searches. Considering a simple projection for the efficiency improvements in the Tevatron analyses, we find that with an integrated luminosity of 16 fb{sup -1} per detector and an efficiency improvement of 20% compared to the present situation, these models could be probed essentially over their entire ranges of validity. With 40% analysis improvements and 16 fb{sup -1}, our projection shows that evidence at the 3{sigma} level for the light Higgs boson could be expected in extended regions of parameter space.

  11. Probing the Higgs sector of high-scale supersymmetry-breaking models at the Tevatron

    SciTech Connect

    Carena, Marcela; Draper, Patrick; Heinemeyer, Sven; Liu, Tao; Wagner, Carlos E. M.; Weiglein, Georg

    2011-03-01

    A canonical signature of the minimal supersymmetric standard model (MSSM) is the presence of a neutral Higgs boson with mass bounded from above by about 135 GeV and standard model (SM)-like couplings to the electroweak gauge bosons. In this paper we investigate the reach of the Tevatron collider for the MSSM Higgs sector parameter space associated with a variety of high-scale minimal models of supersymmetry (SUSY) breaking, including the constrained MSSM, minimal gauge-mediated SUSY breaking, and minimal anomaly-mediated SUSY breaking. We find that the Tevatron can provide strong constraints on these models via Higgs boson searches. Considering a simple projection for the efficiency improvements in the Tevatron analyses, we find that with an integrated luminosity of 16 fb{sup -1} per detector and an efficiency improvement of 20% compared to the present situation, these models could be probed essentially over their entire ranges of validity. With 40% analysis improvements and 16 fb{sup -1}, our projection shows that evidence at the 3{sigma} level for the light Higgs boson could be expected in extended regions of parameter space.

  12. Nuclear 111Cd probes detect a hidden symmetry change at the γ → α transition in cerium considered isostructural for 60 years

    NASA Astrophysics Data System (ADS)

    Tsvyashchenko, A. V.; Nikolaev, A. V.; Velichkov, A. I.; Salamatin, A. V.; Fomicheva, L. N.; Ryasny, G. K.; Sorokin, A. A.; Kochetov, O. I.; Budzynski, M.

    2010-10-01

    We use the time-differential perturbed angular correlation technique to study nuclear electric quadupole hyperfine interactions of probe 111Cd nuclei in cerium lattice sites at room temperature under pressures up to 8 GPa. We have found that the well known γ → α phase transition in cerium is not isostructural. In α-Ce, the probe 111Cd nuclei reveal a quadrupole electron charge density component that is absent in γ-Ce. The hidden spacial structure of electronic quadrupoles in α-Ce is triple-q antiferroquadrupolar, as was suggested in [14]. We relate our findings to the current understanding of the γ → α phase transition and also report on nuclear quadrupole interactions in other high-pressure phases of cerium: α″ ( C2/ m space symmetry) and α' (α-U structure).

  13. Nuclear {sup 111}Cd probes detect a hidden symmetry change at the {gamma} {sup {yields} {alpha}} transition in cerium considered isostructural for 60 years

    SciTech Connect

    Tsvyashchenko, A. V.; Nikolaev, A. V.; Velichkov, A. I.; Salamatin, A. V.; Fomicheva, L. N.; Ryasny, G. K.; Sorokin, A. A.; Kochetov, O. I.; Budzynski, M.

    2010-10-15

    We use the time-differential perturbed angular correlation technique to study nuclear electric quadrupole hyperfine interactions of probe {sup 111}Cd nuclei in cerium lattice sites at room temperature under pressures up to 8 GPa. We have found that the well known {gamma} {sup {yields} {alpha}} phase transition in cerium is not isostructural. In {alpha}-Ce, the probe {sup 111}Cd nuclei reveal a quadrupole electron charge density component that is absent in {gamma}-Ce. The hidden spacial structure of electronic quadrupoles in {alpha}-Ce is triple-q antiferroquadrupolar, as was suggested in [14]. We relate our findings to the current understanding of the {gamma} {sup {yields} {alpha}} phase transition and also report on nuclear quadrupole interactions in other high-pressure phases of cerium: {alpha}'' (C2/m space symmetry) and {alpha}' ({alpha}-U structure).

  14. Hidden charged dark matter and chiral dark radiation

    NASA Astrophysics Data System (ADS)

    Ko, P.; Nagata, Natsumi; Tang, Yong

    2017-10-01

    In the light of recent possible tensions in the Hubble constant H0 and the structure growth rate σ8 between the Planck and other measurements, we investigate a hidden-charged dark matter (DM) model where DM interacts with hidden chiral fermions, which are charged under the hidden SU(N) and U(1) gauge interactions. The symmetries in this model assure these fermions to be massless. The DM in this model, which is a Dirac fermion and singlet under the hidden SU(N), is also assumed to be charged under the U(1) gauge symmetry, through which it can interact with the chiral fermions. Below the confinement scale of SU(N), the hidden quark condensate spontaneously breaks the U(1) gauge symmetry such that there remains a discrete symmetry, which accounts for the stability of DM. This condensate also breaks a flavor symmetry in this model and Nambu-Goldstone bosons associated with this flavor symmetry appear below the confinement scale. The hidden U(1) gauge boson and hidden quarks/Nambu-Goldstone bosons are components of dark radiation (DR) above/below the confinement scale. These light fields increase the effective number of neutrinos by δNeff ≃ 0.59 above the confinement scale for N = 2, resolving the tension in the measurements of the Hubble constant by Planck and Hubble Space Telescope if the confinement scale is ≲1 eV. DM and DR continuously scatter with each other via the hidden U(1) gauge interaction, which suppresses the matter power spectrum and results in a smaller structure growth rate. The DM sector couples to the Standard Model sector through the exchange of a real singlet scalar mixing with the Higgs boson, which makes it possible to probe our model in DM direct detection experiments. Variants of this model are also discussed, which may offer alternative ways to investigate this scenario.

  15. Probing the W-Z-Higgs sector of electroweak gauge theories at the superconducting super collider

    SciTech Connect

    Gunion, J.F.

    1986-10-01

    We review and summarize the procedures for exploring at the SSC the W-Z-Higgs sector of SU(2)/sub L/ x U(1) and extended gauge theory versions thereof, including supersymmetric and left-right symmetric models.

  16. Apatite as probe for the halogen composition of metamorphic fluids (Bamble Sector, SE Norway)

    NASA Astrophysics Data System (ADS)

    Kusebauch, Christof; John, Timm; Whitehouse, Martin J.; Engvik, Ane K.

    2015-10-01

    Halogen composition of replaced apatite formed during a regional metasomatic event (Bamble Sector, SE Norway) reveals information about the composition and evolution of the hydrothermal fluid. Infiltration and pervasive fluid flow of highly saline fluids into gabbroic bodies lead to scapolitization and amphibolitization, where magmatic Cl-rich apatite reacts with the hydrothermal fluid to form OH- and/or F-rich apatite. Apatite from highly altered samples adjacent to the shear zone has highest F (up to 15,000 µg/g) and lowest Br (4-25 µg/g) concentrations, whereas apatite from least altered samples has very low F (30-200 µg/g) and high Br (30-85 µg/g). In addition, individual replaced apatite grains show a zonation in F with high concentrations along rims and cracks and low F in core regions. Iodine concentrations remain rather constant as low values of 0.18-0.70 µg/g. We interpret all observed compositional features of replaced apatite to be the result of a continuous evolution of the fluid during fluid-rock interaction. Due to its high compatibility, F from the infiltrating fluid is incorporated early into recrystallized apatite (close to shear zone and rims of individual apatite grains). In contrast, Br as an incompatible halogen becomes enriched in the fluid and is highest in the most evolved fluid. Using experimental partition data between replaced apatite and fluid, we calculated F concentrations of the evolving fluid to decrease from 60 to <1 µg/g and Br to increase from ~1200 to ~5000 µg/g; I concentrations of the fluid are constant in the order of 370 µg/g. Although Cl is expected to show a similar behavior as Br, replaced apatite has constant Cl concentrations throughout the alteration sequence (~1 wt.%), which is likely the result of a rather constant Cl activity in the fluid. Chlorine stable isotope values of individual apatite grains are heterogeneous and range from -1.2 to +3.7 ‰. High δ 37Cl values are generally correlated with OH

  17. A MAGNIFIED GLANCE INTO THE DARK SECTOR: PROBING COSMOLOGICAL MODELS WITH STRONG LENSING IN A1689

    SciTech Connect

    Magaña, Juan; Motta, V.; Cárdenas, Victor H.; Verdugo, T.; Jullo, Eric E-mail: veronica.motta@uv.cl E-mail: tomasverdugo@gmail.com

    2015-11-01

    In this paper we constrain four alternative models to the late cosmic acceleration in the universe: Chevallier–Polarski–Linder (CPL), interacting dark energy (IDE), Ricci holographic dark energy (HDE), and modified polytropic Cardassian (MPC). Strong lensing (SL) images of background galaxies produced by the galaxy cluster Abell 1689 are used to test these models. To perform this analysis we modify the LENSTOOL lens modeling code. The value added by this probe is compared with other complementary probes: Type Ia supernovae (SN Ia), baryon acoustic oscillations (BAO), and cosmic microwave background (CMB). We found that the CPL constraints obtained for the SL data are consistent with those estimated using the other probes. The IDE constraints are consistent with the complementary bounds only if large errors in the SL measurements are considered. The Ricci HDE and MPC constraints are weak, but they are similar to the BAO, SN Ia, and CMB estimations. We also compute the figure of merit as a tool to quantify the goodness of fit of the data. Our results suggest that the SL method provides statistically significant constraints on the CPL parameters but is weak for those of the other models. Finally, we show that the use of the SL measurements in galaxy clusters is a promising and powerful technique to constrain cosmological models. The advantage of this method is that cosmological parameters are estimated by modeling the SL features for each underlying cosmology. These estimations could be further improved by SL constraints coming from other galaxy clusters.

  18. A Magnified Glance into the Dark Sector: Probing Cosmological Models with Strong Lensing in A1689

    NASA Astrophysics Data System (ADS)

    Magaña, Juan; Motta, V.; Cárdenas, Víctor H.; Verdugo, T.; Jullo, Eric

    2015-11-01

    In this paper we constrain four alternative models to the late cosmic acceleration in the universe: Chevallier-Polarski-Linder (CPL), interacting dark energy (IDE), Ricci holographic dark energy (HDE), and modified polytropic Cardassian (MPC). Strong lensing (SL) images of background galaxies produced by the galaxy cluster Abell 1689 are used to test these models. To perform this analysis we modify the LENSTOOL lens modeling code. The value added by this probe is compared with other complementary probes: Type Ia supernovae (SN Ia), baryon acoustic oscillations (BAO), and cosmic microwave background (CMB). We found that the CPL constraints obtained for the SL data are consistent with those estimated using the other probes. The IDE constraints are consistent with the complementary bounds only if large errors in the SL measurements are considered. The Ricci HDE and MPC constraints are weak, but they are similar to the BAO, SN Ia, and CMB estimations. We also compute the figure of merit as a tool to quantify the goodness of fit of the data. Our results suggest that the SL method provides statistically significant constraints on the CPL parameters but is weak for those of the other models. Finally, we show that the use of the SL measurements in galaxy clusters is a promising and powerful technique to constrain cosmological models. The advantage of this method is that cosmological parameters are estimated by modeling the SL features for each underlying cosmology. These estimations could be further improved by SL constraints coming from other galaxy clusters.

  19. Channel probe measurements for the American sector clutter experiment, January, 1994

    SciTech Connect

    Fitzgerald, T.J.

    1994-05-20

    The ionospheric phenomenon called Equatorial Spread F encompasses a variety of effects associated with plasma irregularities occurring in the post-sunset and nighttime ionosphere near the magnetic equator. These irregularities can seriously degrade the performance of systems which involve either of necessity or inadvertently radio propagation through the equatorial ionosphere. One such system is Over-the-Horizon (OTH) radars which operate in the high-frequency (hf) band and use ionospheric reflection for forward and backscatter propagation to ranges of thousands of kilometers. When such radars are directed towards the equator, Spread F irregularities can cause scintillation effects which may be aliased into the ranges of interest and have the effect of causing, excess clutter in which targets may be hidden. In January, 1994 Los Alamos participated in a campaign to measure Spread F effects on OTH propagation from the United States looking towards South America in conjunction with local diagnostics in Peru. During the campaign Los Alamos fielded a 1600 km bistatic path between Piura, Peru, and Arequipa, Peru-, the one-hop reflection region for this path was near the magnetic equator, We obtained four types of measurements: an oblique ionogram between Piura and Arequipa every three minutes; Doppler spread and spatial correlation for a single frequency cw path between Piura and Arequipa; Doppler spread, time-delay spread, and spatial coherence for a 10 kHz bandwidth path between Piura and Arequipa-, and Doppler spread and time-delay spread for the one-way path between the AVA radar in New York and Arequipa, Peru. This report describes the diagnostic experiments that we carried out and gives a brief description of some of the data we obtained.

  20. Dark-matter decay as a complementary probe of multicomponent dark sectors.

    PubMed

    Dienes, Keith R; Kumar, Jason; Thomas, Brooks; Yaylali, David

    2015-02-06

    In single-component theories of dark matter, the 2→2 amplitudes for dark-matter production, annihilation, and scattering can be related to each other through various crossing symmetries. The detection techniques based on these processes are thus complementary. However, multicomponent theories exhibit an additional direction for dark-matter complementarity: the possibility of dark-matter decay from heavier to lighter components. We discuss how this new detection channel may be correlated with the others, and demonstrate that the enhanced complementarity which emerges can be an important ingredient in probing and constraining the parameter spaces of such models.

  1. STELLAR MASS-GAP AS A PROBE OF HALO ASSEMBLY HISTORY AND CONCENTRATION: YOUTH HIDDEN AMONG OLD FOSSILS

    SciTech Connect

    Deason, A. J.; Conroy, C.; Wetzel, A. R.; Tinker, J. L.

    2013-11-10

    We investigate the use of the halo mass-gap statistic—defined as the logarithmic difference in mass between the host halo and its most massive satellite subhalo—as a probe of halo age and concentration. A cosmological N-body simulation is used to study N ∼ 25, 000 group/cluster-sized halos in the mass range 10{sup 12.5} < M{sub halo}/M{sub ☉} < 10{sup 14.5}. In agreement with previous work, we find that halo mass-gap is related to halo formation time and concentration. On average, older and more highly concentrated halos have larger halo mass-gaps, and this trend is stronger than the mass-concentration relation over a similar dynamic range. However, there is a large amount of scatter owing to the transitory nature of the satellite subhalo population, which limits the use of the halo mass-gap statistic on an object-by-object basis. For example, we find that 20% of very large halo mass-gap systems (akin to {sup f}ossil groups{sup )} are young and have likely experienced a recent merger between a massive satellite subhalo and the central subhalo. We relate halo mass-gap to the observable stellar mass-gap via abundance matching. Using a galaxy group catalog constructed from the Sloan Digital Sky Survey Data Release 7, we find that the star formation and structural properties of galaxies at fixed mass show no trend with stellar mass-gap. This is despite a variation in halo age of ≈2.5 Gyr over ≈1.2 dex in stellar mass-gap. Thus, we find no evidence to suggest that the halo formation history significantly affects galaxy properties.

  2. Chiral Dark Sector

    NASA Astrophysics Data System (ADS)

    Co, Raymond T.; Harigaya, Keisuke; Nomura, Yasunori

    2017-03-01

    We present a simple and natural dark sector model in which dark matter particles arise as composite states of hidden strong dynamics and their stability is ensured by accidental symmetries. The model has only a few free parameters. In particular, the gauge symmetry of the model forbids the masses of dark quarks, and the confinement scale of the dynamics provides the unique mass scale of the model. The gauge group contains an Abelian symmetry U (1 )D , which couples the dark and standard model sectors through kinetic mixing. This model, despite its simple structure, has rich and distinctive phenomenology. In the case where the dark pion becomes massive due to U (1 )D quantum corrections, direct and indirect detection experiments can probe thermal relic dark matter which is generically a mixture of the dark pion and the dark baryon, and the Large Hadron Collider can discover the U (1 )D gauge boson. Alternatively, if the dark pion stays light due to a specific U (1 )D charge assignment of the dark quarks, then the dark pion constitutes dark radiation. The signal of this radiation is highly correlated with that of dark baryons in dark matter direct detection.

  3. Parametrically enhanced hidden photon search

    NASA Astrophysics Data System (ADS)

    Graham, Peter W.; Mardon, Jeremy; Rajendran, Surjeet; Zhao, Yue

    2014-10-01

    Many theories beyond the Standard Model contain hidden photons. A light hidden photon will generically couple to the Standard Model through a kinetic mixing term, giving a powerful avenue for detection using "light-shining-through-a-wall"-type transmission experiments with resonant cavities. We demonstrate a parametric enhancement of the signal in such experiments, resulting from transmission of the longitudinal mode of the hidden photon. While previous literature has focused on the production and detection of transverse modes, the longitudinal mode allows a significant improvement in experimental sensitivity. Although optical experiments such as ALPS are unable to take useful advantage of this enhancement, the reach of existing microwave cavity experiments such as CROWS is significantly enhanced beyond their published results. Future microwave cavity experiments, designed with appropriate geometry to take full advantage of the longitudinal mode, will provide a powerful probe of hidden-photon parameter space extending many orders of magnitude beyond current limits, including significant regions where the hidden photon can be dark matter.

  4. Support for Students with Hidden Disabilities in Universities: A Case Study

    ERIC Educational Resources Information Center

    Couzens, Donna; Poed, Shiralee; Kataoka, Mika; Brandon, Alicia; Hartley, Judy; Keen, Deb

    2015-01-01

    More students with disabilities are accessing the tertiary sector with many disabilities not easily observed (or hidden), because there are no physical indicators. These "hidden" disabilities affect a variety of cognitive processes and may be developmental or acquired. To ensure students with hidden disabilities can enrol, engage in and…

  5. Herschel Observations of EXtra-Ordinary Sources: H2S as a Probe of Dense Gas and Possibly Hidden Luminosity Toward the Orion KL Hot Core

    NASA Astrophysics Data System (ADS)

    Crockett, N. R.; Bergin, E. A.; Neill, J. L.; Black, J. H.; Blake, G. A.; Kleshcheva, M.

    2014-02-01

    We present Herschel/HIFI observations of the light hydride H2S obtained from the full spectral scan of the Orion Kleinmann-Low nebula (Orion KL) taken as part of the Herschel Observations of EXtra-Ordinary Sources GT (guaranteed time) key program. In total, we observe 52, 24, and 8 unblended or slightly blended features from H2 32S, H2 34S, and H2 33S, respectively. We only analyze emission from the so-called hot core, but emission from the plateau, extended ridge, and/or compact ridge are also detected. Rotation diagrams for ortho and para H2S follow straight lines given the uncertainties and yield T rot = 141 ± 12 K. This indicates H2S is in local thermodynamic equilibrium and is well characterized by a single kinetic temperature or an intense far-IR radiation field is redistributing the population to produce the observed trend. We argue the latter scenario is more probable and find that the most highly excited states (E up >~ 1000 K) are likely populated primarily by radiation pumping. We derive a column density, N tot(H2 32S) = 9.5 ± 1.9 × 1017 cm-2, gas kinetic temperature, T kin = 120+/- ^{13}_{10} K, and constrain the H2 volume density, n_H_2 >~ 9 × 10 7 cm-3, for the H2S emitting gas. These results point to an H2S origin in markedly dense, heavily embedded gas, possibly in close proximity to a hidden self-luminous source (or sources), which are conceivably responsible for Orion KL's high luminosity. We also derive an H2S ortho/para ratio of 1.7 ± 0.8 and set an upper limit for HDS/H2S of <4.9 × 10 -3. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  6. Dark matter freeze-out in a nonrelativistic sector

    NASA Astrophysics Data System (ADS)

    Pappadopulo, Duccio; Ruderman, Joshua T.; Trevisan, Gabriele

    2016-08-01

    A thermally decoupled hidden sector of particles, with a mass gap, generically enters a phase of cannibalism in the early Universe. The Standard Model sector becomes exponentially colder than the hidden sector. We propose the cannibal dark matter framework, where dark matter resides in a cannibalizing sector with a relic density set by 2-to-2 annihilations. Observable signals of cannibal dark matter include a boosted rate for indirect detection, new relativistic degrees of freedom, and warm dark matter.

  7. Probing sub-GeV dark sectors via high energy proton beams at LBNF/DUNE and MiniBooNE

    NASA Astrophysics Data System (ADS)

    Frugiuele, Claudia

    2017-07-01

    We study the sensitivity to sub-GeV dark sectors of high energy (≥100 GeV ) proton fixed target experiments such as the Main Injector and the future Long-Baseline Neutrino Facility (LBNF). We focus on off-axis detectors since they have been shown to be the ideal location to reduce the neutrino background. We consider MiniBooNE as an off-axis detector for the NuMI facility and a hyphotetical detector for LBNF located 200 m away from the target and 6.5 degrees off-axis. We find that with the existing data, MiniBooNE can explore new regions of the parameter space for leptophobic dark forces in the 100 MeV-few GeV mass range. The dedicated MiniBooNE run in beam dump mode would further improve the reach for even lighter masses. Therefore, MiniBooNE has the potential to be one of the most sensitive probes of leptophobic dark forces for masses between 1 MeV-10 GeV. Hence we encourage MiniBooNE collaboration to perform a DM dedicated analysis of the existing data coming from neutrinos produced at the Main Injector.

  8. Hidden SU(N) glueball dark matter

    DOE PAGES

    Soni, Amarjit; Zhang, Yue

    2016-06-21

    Here we investigate the possibility that the dark matter candidate is from a pure non-abelian gauge theory of the hidden sector, motivated in large part by its elegance and simplicity. The dark matter is the lightest bound state made of the confined gauge fields, the hidden glueball. We point out this simple setup is capable of providing rich and novel phenomena in the dark sector, especially in the parameter space of large N. They include self-interacting and warm dark matter scenarios, Bose-Einstein condensation leading to massive dark stars possibly millions of times heavier than our sun giving rise to gravitationalmore » lensing effects, and indirect detections through higher dimensional operators as well as interesting collider signatures.« less

  9. Discovering the Hidden Person.

    ERIC Educational Resources Information Center

    Zener, Rita; Ezcurdia, Laura Noriega

    1997-01-01

    Working from normalization theory, uses a graphical metaphor to illustrate the liberation of the "hidden self." Explains the layers of the metaphor, the "false person," the "intelligent, rational person," and the "hidden person," and offers several ways educators can work to uncover the layers surrounding…

  10. POVMs and hidden variables

    NASA Astrophysics Data System (ADS)

    Stairs, Allen

    2007-06-01

    Recent results by Paul Busch and Adán Cabello claim to show that by appealing to POVMs, non-contextual hidden variables can be ruled out in two dimensions. While the results of Busch and Cabello are mathematically correct, interpretive problems render them problematic as no hidden variable proofs.

  11. Probing the hidden secrets of Seyfert nuclei.

    NASA Astrophysics Data System (ADS)

    Appenzeller, I.; Wagner, S.

    1990-06-01

    The nuclei of active galaxies are clearly among the most spectacular and violent places that can be found in our present universe. Most extreme are the bright Quasars, where we observe a total energy output equivalent to a large galaxy cluster from galactic core regions comparable in size to our solar system. In addition to optical and radio radiation we often observe intense X-ray and even energetic Gamma radiation as well as collimated streams of matter moving at velocities close to the velocity of light.

  12. Lightest Visible-Sector Supersymmetric Particle is Likely to be Unstable

    NASA Astrophysics Data System (ADS)

    Acharya, Bobby S.; Ellis, Sebastian A. R.; Kane, Gordon L.; Nelson, Brent D.; Perry, Malcolm J.

    2016-10-01

    We argue, based on typical properties of known solutions of string or M theory, that the lightest supersymmetric particle of the visible sector is likely to be unstable. In other words, dark matter is probably not a particle with standard model quantum numbers, such as a weakly interacting massive particle. The argument is simple and based on the typical occurrence of (a) hidden sectors, (b) interactions between the standard model (visible) sector and these hidden sectors, and (c) the lack of an argument against massive neutral hidden sector particles being lighter than the lightest visible supersymmetric particle. These conclusions do not rely on arguments such as R -parity violation.

  13. Probe into Gaseous Pollution and Assessment of Air Quality Benefit under Sector Dependent Emission Control Strategies over Megacities in Yangtze River Delta, China

    SciTech Connect

    Dong, Xinyi; Gao, Yang; Fu, Joshua S.; Li, Juan; Huang, Kan; Zhuang, G.; Zhou, Ying

    2013-11-01

    On February 29th 2012, China published its new National Ambient Air Quality Standard (CH-NAAQS) aiming at revising the standards and measurements for both gaseous pollutants including ozone (O3), nitrogen dioxide (NO2), and sulfur dioxide (SO2), and also particle pollutants including PM10 and PM2.5. In order to understand the air pollution status regarding this new standard, the integrated MM5/CMAQ modeling system was applied over Yangtze River Delta (YRD) within this study to examine the criteria gaseous pollutants listed in the new CH-NAAQS. Sensitivity simulations were also conducted to assess the responses of gaseous pollutants under 8 different sector-dependent emission reduction scenarios in order to evaluate the potential control strategies. 2006 was selected as the simulation year in order to review the air quality condition at the beginning of China’s 11th Five-Year-Plan (FYP, from 2006 to 2010), and also compared with air quality status in 2010 as the end of 11th FYP to probe into the effectiveness of the national emission control efforts. Base case simulation showed distinct seasonal variation for gaseous pollutants: SO2, and NO2 were found to have higher surface concentrations in winter while O3 was found to have higher concentrations in spring and summer than other seasons. According to the analyses focused on 3 megacities within YRD, Shanghai, Nanjing, and Hangzhou, we found different air quality conditions among the cities: NO2 was the primary pollutant that having the largest number of days exceeding the CH-NAAQS daily standard (80 μg/m3) in Shanghai (59 days) and Nanjing (27 days); SO2 was the primary pollutant with maximum number of days exceeding daily air quality standard (150 μg/m3) in Hangzhou (28 days), while O3 exceeding the daily maximum 8-hour standard (160 μg/m3) for relatively fewer days in all the three cities (9 days in Shanghai, 14 days in Nanjing, and 11 days in Hangzhou). Simulation results from predefined potential applicable

  14. Probe into gaseous pollution and assessment of air quality benefit under sector dependent emission control strategies over megacities in Yangtze River Delta, China

    NASA Astrophysics Data System (ADS)

    Dong, Xinyi; Gao, Yang; Fu, Joshua S.; Li, Juan; Huang, Kan; Zhuang, Guoshun; Zhou, Ying

    2013-11-01

    On February 29th 2012, China published its new National Ambient Air Quality Standard (CH-NAAQS) aiming at revising the standards and measurements for both gaseous pollutants including ozone (O3), nitrogen dioxide (NO2), and sulfur dioxide (SO2), and also particle pollutants including PM10 and PM2.5. In order to understand the air pollution status regarding this new standard, the integrated MM5/CMAQ modeling system was applied over Yangtze River Delta (YRD) within this study to examine the criteria gaseous pollutants listed in the new CH-NAAQS. Sensitivity simulations were also conducted to assess the responses of gaseous pollutants under 8 different sector-dependent emission reduction scenarios in order to evaluate the potential control strategies. 2006 was selected as the simulation year in order to review the air quality condition at the beginning of China's 11th Five-Year-Plan (FYP, from 2006 to 2010), and also compared with air quality status in 2010 as the end of 11th FYP to probe into the effectiveness of the national emission control efforts. Base case simulation showed distinct seasonal variation for gaseous pollutants: SO2, and NO2 were found to have higher surface concentrations in winter while O3 was found to have higher concentrations in spring and summer than other seasons. According to the analyses focused on 3 megacities within YRD, Shanghai, Nanjing, and Hangzhou, we found different air quality conditions among the cities: NO2 was the primary pollutant that having the largest number of days exceeding the CH-NAAQS daily standard (80 μg m-3) in Shanghai (59 days) and Nanjing (27 days); SO2 was the primary pollutant with maximum number of days exceeding daily air quality standard (150 μg m-3) in Hangzhou (28 days), while O3 exceeding the daily maximum 8-h standard (160 μg m-3) for relatively fewer days in all the three cities (9 days in Shanghai, 14 days in Nanjing, and 11 days in Hangzhou). Simulation results from predefined potential applicable

  15. Unparticles: Scales and high energy probes

    SciTech Connect

    Bander, Myron; Feng, Jonathan L.; Rajaraman, Arvind; Shirman, Yuri

    2007-12-01

    Unparticles from hidden conformal sectors provide qualitatively new possibilities for physics beyond the standard model. In the theoretical framework of minimal models, we clarify the relation between energy scales entering various phenomenological analyses. We show that these relations always counteract the effective field theory intuition that higher dimension operators are more highly suppressed, and that the requirement of a significant conformal window places strong constraints on possible unparticle signals. With these considerations in mind, we examine some of the most robust and sensitive probes and explore novel effects of unparticles on gauge coupling evolution and fermion production at high energy colliders. These constraints are presented both as bounds on four-fermion interaction scales and as constraints on the fundamental parameter space of minimal models.

  16. Hidden circuits and argumentation

    NASA Astrophysics Data System (ADS)

    Leinonen, Risto; Kesonen, Mikko H. P.; Hirvonen, Pekka E.

    2016-11-01

    Despite the relevance of DC circuits in everyday life and schools, they have been shown to cause numerous learning difficulties at various school levels. In the course of this article, we present a flexible method for teaching DC circuits at lower secondary level. The method is labelled as hidden circuits, and the essential idea underlying hidden circuits is in hiding the actual wiring of DC circuits, but to make their behaviour evident for pupils. Pupils are expected to find out the wiring of the circuit which should enhance their learning of DC circuits. We present two possible ways to utilise hidden circuits in a classroom. First, they can be used to test and enhance pupils’ conceptual understanding when pupils are expected to find out which one of the offered circuit diagram options corresponds to the actual circuit shown. This method aims to get pupils to evaluate the circuits holistically rather than locally, and as a part of that aim this method highlights any learning difficulties of pupils. Second, hidden circuits can be used to enhance pupils’ argumentation skills with the aid of argumentation sheet that illustrates the main elements of an argument. Based on the findings from our co-operating teachers and our own experiences, hidden circuits offer a flexible and motivating way to supplement teaching of DC circuits.

  17. New limits on hidden photons from past electron beam dumps

    NASA Astrophysics Data System (ADS)

    Andreas, Sarah; Niebuhr, Carsten; Ringwald, Andreas

    2012-11-01

    Hidden sectors with light extra U(1) gauge bosons, so-called hidden photons, have recently attracted some attention because they are a common feature of physics beyond the Standard Model like string theory and supersymmetry and additionally are phenomenologically of great interest regarding recent astrophysical observations. The hidden photon is already constrained by various laboratory experiments and presently searched for in running as well as upcoming experiments. We summarize the current status of limits on hidden photons from past electron beam dump experiments including two new limits from such experiments at the High Energy Accelerator Research Organization in Japan (KEK) and the Laboratoire de l’accelérateur linéaire (LAL, Orsay) that have so far not been considered. All our limits take into account the experimental acceptances obtained from Monte Carlo simulations.

  18. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, members of the media participate in a news conference with key individuals from the upcoming motion picture "Hidden Figures." From the left are: Ted Melfi (partially visible), writer and director of “Hidden Figures”; Octavia Spencer, who portrays Dorothy Vaughan; Taraji P. Henson, who portrays Katherine Johnson in the film; Janelle Monáe, who portrays Mary Jackson; Pharrell Williams, musician and producer of “Hidden Figures"; and Bill Barry, NASA's chief historian. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  19. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, members of the media participate in a news conference with key individuals from the upcoming motion picture "Hidden Figures." From the left are: Ted Melfi, writer and director of “Hidden Figures”; Octavia Spencer, who portrays Dorothy Vaughan; Taraji P. Henson, who portrays Katherine Johnson in the film; Janelle Monáe, who portrays Mary Jackson; Pharrell Williams, musician and producer of “Hidden Figures"; and Bill Barry, NASA's chief historian. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  20. WIMPless dark matter in anomaly-mediated supersymmetry breaking with hidden QED

    NASA Astrophysics Data System (ADS)

    Feng, Jonathan L.; Rentala, Vikram; Surujon, Ze'Ev

    2011-11-01

    In anomaly-mediated supersymmetry breaking, superpartners in a hidden sector have masses that are proportional to couplings squared and so naturally freeze out with the desired dark matter relic density for a large range of masses. We present an extremely simple realization of this possibility, with WIMPless dark matter arising from a hidden sector that is supersymmetric QED with NF flavors. Dark matter is multicomponent, composed of hidden leptons and sleptons with masses anywhere from 10 GeV to 10 TeV, and hidden photons provide the thermal bath. The dark matter self-interacts through hidden sector Coulomb scatterings that are potentially observable. In addition, the hidden photon contribution to the number of relativistic degrees of freedom is in the range ΔNeff˜0-2, and, if the hidden and visible sectors were initially in thermal contact, the model predicts ΔNeff˜0.2-0.4. Data already taken by Planck may provide evidence of such deviations.

  1. Multistability: Uncovering hidden attractors

    NASA Astrophysics Data System (ADS)

    Kapitaniak, T.; Leonov, G. A.

    2015-07-01

    This topical issue collects contributions exemplifying the recent scientific progress in understanding the dynamics of multistable systems. The individual papers focus on different questions of present day interest in theory and applications of systems with multiple attractors. The particular attention is paid to uncovering and characterizing hidden attractors. Both theoretical and experimental studies are presented.

  2. Hazing: Hidden Campus Crime.

    ERIC Educational Resources Information Center

    Hollmann, Barbara B.

    2002-01-01

    Initiation traditions and rites of passage are important for group and team membership, but the violent behavior and alcohol abuse involved in hazing constitute serious campus crime. This article helps campus administrators to develop new strategies for attacking the hidden crime of hazing. (Contains 32 references.) (Author)

  3. Hidden Behavior in Graphs.

    ERIC Educational Resources Information Center

    Donley, H. Edward; George, Elizabeth Ann

    1993-01-01

    Demonstrates how to construct rational, exponential, and sinusoidal functions that appear normal on one scale but exhibit interesting hidden behavior when viewed on another scale. By exploring these examples, students learn the importance of scale, window size, and resolution effects in computer and calculator graphing. (MAZ)

  4. Agriculture Sectors

    EPA Pesticide Factsheets

    The Agriculture sectors comprise establishments primarily engaged in growing crops, raising animals, and harvesting fish and other animals. Find information on compliance, enforcement and guidance on EPA laws and regulations on the NAICS 111 & 112 sectors.

  5. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    During a tour for cast and crew members of the upcoming motion picture "Hidden Figures," Kennedy Space Center Director Bob Cabana points to Launch Pads 39A and 39B from the roof of the Vehicle Assembly Building. In the foreground is Pharrell Williams, musician and producer of “Hidden Figures." The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  6. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Kennedy Space Center Associate Director Kelvin Manning, left, and Center Director Bob Cabana, center, provide a tour for cast and crew members of the upcoming motion picture "Hidden Figures." They are reviewing a display at near the blockhouse at Cape Canaveral Air Force Station's Launch Pad 14 with Pharrell Williams, musician and producer of “Hidden Figures." The pad was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  7. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Kennedy Space Center Director Bob Cabana provides a tour for cast and crew members of the upcoming motion picture "Hidden Figures." From the left are Cabana, Pharrell Williams, musician and producer of “Hidden Figures," Taraji P. Henson, who portrays Katherine Johnson in the film, and Octavia Spencer, who portrays Dorothy Vaughan. The group is walking thought the transfer aisle of the Vehicle Assembly Building. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  8. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    During a tour for cast and crew members of the upcoming motion picture "Hidden Figures," Kennedy Space Center Director Bob Cabana points to Launch Pads 39A and 39B from the roof of the Vehicle Assembly Building. From the left are Octavia Spencer, who portrays Dorothy Vaughan in the film, Cabana, Taraji P. Henson, who portrays Katherine Johnson, and Pharrell Williams, musician and producer of “Hidden Figures." The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  9. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Kennedy Space Center Director Bob Cabana speaks cast and crew members of the upcoming motion picture "Hidden Figures" outside the Vehicle Assembly Building. From the left are Pharrell Williams, musician and producer of “Hidden Figures," Taraji P. Henson, who portrays Katherine Johnson in the film and Cabana. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  10. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, members of the media participate in a news conference with key individuals involved in the upcoming motion picture "Hidden Figures." From the left are: Janelle Monáe, who portrays Mary Jackson; Pharrell Williams, musician and producer of “Hidden Figures;" and Bill Barry, NASA's chief historian. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  11. Probing neutrino and Higgs sectors in { SU(2) }_1 × { SU(2) }_2 × { U(1) }_Y model with lepton-flavor non-universality

    NASA Astrophysics Data System (ADS)

    Hue, L. T.; Arbuzov, A. B.; Ngan, N. T. K.; Long, H. N.

    2017-05-01

    The neutrino and Higgs sectors in the { SU(2) }_1 × { SU(2) }_2 × { U(1) }_Y model with lepton-flavor non-universality are discussed. We show that active neutrinos can get Majorana masses from radiative corrections, after adding only new singly charged Higgs bosons. The mechanism for the generation of neutrino masses is the same as in the Zee models. This also gives a hint to solving the dark matter problem based on similar ways discussed recently in many radiative neutrino mass models with dark matter. Except the active neutrinos, the appearance of singly charged Higgs bosons and dark matter does not affect significantly the physical spectrum of all particles in the original model. We indicate this point by investigating the Higgs sector in both cases before and after singly charged scalars are added into it. Many interesting properties of physical Higgs bosons, which were not shown previously, are explored. In particular, the mass matrices of charged and CP-odd Higgs fields are proportional to the coefficient of triple Higgs coupling μ . The mass eigenstates and eigenvalues in the CP-even Higgs sector are also presented. All couplings of the SM-like Higgs boson to normal fermions and gauge bosons are different from the SM predictions by a factor c_h, which must satisfy the recent global fit of experimental data, namely 0.995<|c_h|<1. We have analyzed a more general diagonalization of gauge boson mass matrices, then we show that the ratio of the tangents of the W-W' and Z-Z' mixing angles is exactly the cosine of the Weinberg angle, implying that number of parameters is reduced by 1. Signals of new physics from decays of new heavy fermions and Higgs bosons at LHC and constraints of their masses are also discussed.

  12. Locating Hidden Servers

    DTIC Science & Technology

    2006-01-01

    Syverson Naval Research Laboratory syverson@itd.nrl.navy.mil Abstract Hidden services were deployed on the Tor anonymous communication network in 2004. An...services over Tor, our results apply to any client us- ing a variety of anonymity networks. In fact, these are the first actual intersection attacks...we have demonstrated. They have been implemented. 1 Introduction Tor is a distributed low-latency anonymous communication network developed by the

  13. Detecting Hidden Communications Protocols

    DTIC Science & Technology

    2013-02-11

    Release The work funded by the grant is structured in three parts: We analyzed the vulnerability of the current generation anonymity tools to...traffic analysis attacks. We specifically concentrate on SSH security and The Onion Router (Tor) anonymity tools. Our analysis used deterministic hidden...grant is structured in three parts: I. We analyzed the vulnerability of the current generation anonymity tools to traffic analysis attacks. We

  14. Addressing hidden financial risk.

    PubMed

    Kruger, Jan; Kruger, Jan

    2014-02-01

    Managing low-dollar, high-volume claim denials associated with outpatient procedures is a challenge for many hospitals because of the expense involved in manually reviewing such denials. These denials often are the source of "hidden loss" for hospitals. For some hospitals, the most practical, cost-effective approach for managing low-dollar, high-volume claim denials will include the use of automated systems to monitor and highlight denials and expose trends.

  15. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, members of the media participate in a news conference with key individuals from the upcoming motion picture "Hidden Figures." From the left are: former CNN space correspondent John Zarrella, serving as moderator; Ted Melfi, writer and director of “Hidden Figures”; Octavia Spencer, who portrays Dorothy Vaughan; Taraji P. Henson, who portrays Katherine Johnson in the film; Janelle Monáe, who portrays Mary Jackson; Pharrell Williams, musician and producer of “Hidden Figures"; and Bill Barry, NASA's chief historian. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  16. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    During a tour for cast and crew members of the upcoming motion picture "Hidden Figures," Kennedy Space Center Director Bob Cabana poses with the group on the roof of the Vehicle Assembly Building. Among those participating are Kelvin Manning, associate center director; Meredith Lipsky, vice president of Field Marketing for 20th Century Fox; Ted Melfi, writer and director of “Hidden Figures;” Michelle Ryan, executive producer of the film; Pharrell Williams, musician and producer of “Hidden Figures;" Octavia Spencer, who portrays Dorothy Vaughan; Taraji P. Henson, who portrays Katherine Johnson in the film; Janet Petro, deputy center director; and Cabana. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  17. Hidden solution to the {mu}/B{sub {mu}} problem in gauge mediation

    SciTech Connect

    Roy, Tuhin S.; Schmaltz, Martin

    2008-05-01

    We propose a solution to the {mu}/B{sub {mu}} problem in gauge mediation. The novel feature of our solution is that it uses dynamics of the hidden sector, which is often present in models with dynamical supersymmetry breaking. We give an explicit example model of gauge mediation where a very simple messenger sector generates both {mu} and B{sub {mu}} at one loop. The usual problem, that B{sub {mu}} is then too large, is solved by strong renormalization effects from the hidden sector which suppress B{sub {mu}} relative to {mu}. Our mechanism relies on an assumption about the signs of certain incalculable anomalous dimensions in the hidden sector. Making these assumptions not only allows us to solve the {mu}/B{sub {mu}} problem but also leads to a characteristic superpartner spectrum which would be a smoking gun signal for our mechanism.

  18. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Kennedy Space Center Director Bob Cabana points to a display during a tour for cast and crew members of the upcoming motion picture "Hidden Figures." The group is walking thought the transfer aisle of the Vehicle Assembly Building. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  19. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Kennedy Space Center Director Bob Cabana (center pointing to the left) provides a tour for cast and crew members of the upcoming motion picture "Hidden Figures." The group is walking thought the transfer aisle of the Vehicle Assembly Building. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  20. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, Bill Barry, NASA's chief historian, speaks to members of the media during a a news conference with key individuals involved in the upcoming motion picture "Hidden Figures." The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  1. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Kennedy Space Center Director Bob Cabana (pointing) provides a tour for cast and crew members of the upcoming motion picture "Hidden Figures." The group is walking thought the transfer aisle of the Vehicle Assembly Building. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  2. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, Octavia Spencer speaks to members of the media during a news conference with other key individuals involved in the upcoming motion picture "Hidden Figures." The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan (played by Spencer) and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  3. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    During a tour for cast and crew members of the upcoming motion picture "Hidden Figures," Kennedy Space Center Director Bob Cabana describes the view from the roof of the Vehicle Assembly Building. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  4. The hidden curriculum.

    PubMed

    Rodriguez, Rechell G; Mai, Derek

    2012-09-01

    The Uniformed Services University of the Health Sciences Internal Medicine Third Year Clerkship Program recently instituted an academic exercise to be completed by medical students during the first 6 weeks of their 12 weeks of Internal Medicine. The academic exercise involves reflecting on professional values through art and being exposed to the hidden curriculum of professionalism. Students are instructed at the beginning of their clerkship to observe the professional activities of their teachers, peers, ancillary staff, and of themselves. Students are provided a selection of art pieces to choose from. They select one which best exemplifies the professional activity they observed and are then to write a structured, reflective article.

  5. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    In the blockhouse at Cape Canaveral Air Force Station's Launch Pad 14, cast and crew members of the upcoming motion picture "Hidden Figures" listen to a briefing on the pad which was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. In the foreground, from the left, are Octavia Spencer, who portrays Dorothy Vaughan, Taraji P. Henson, who portrays Katherine Johnson in the film, Janelle Monáe, who portrays Mary Jackson, and Pharrell Williams, musician and producer of “Hidden Figures." The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  6. Student Teaching: A Hidden Wholeness

    ERIC Educational Resources Information Center

    Bowman, Richard F.

    2007-01-01

    Productive student teachers lead learning by emergently sensing and honoring the hidden wholeness of life in classrooms. That hidden wholeness mirrors seven contextual concerns which learners reflect upon in the everydayness of classroom life: What are we going to do in class today? What am I going to have to do in class? What counts in today's…

  7. Probing Soft QCD with Spin and Flavor

    NASA Astrophysics Data System (ADS)

    Jacobs, W. W.

    1998-04-01

    Investigation of the nature of the strong interaction at short (<= 0.1 fm) distance scales probes the transition regime at the interface of perturbative and non-perturbative QCD. Spin and flavor degrees of freedom are a promising way of providing insight into this transition from a purely hadronic (e.g., involving baryons and mesons in an effective theory) to a quark-gluon description. The introduction of strange and charmed quark flavors, in distinction to the more common light (u and d) quark components, can be used to tag reaction channels, probe intrinsic particle structure and help define aspects of the dynamics. Recent results from a strangeness production experiment (DISTO(A. Maggiora for the DISTO collaboration, Nucl. Phys. News 5), 23 (1995).) with 2.85 GeV polarized protons from SATURNE II impinging on a liquid Hydrogen target are presented, including associated and open production as well as hidden strangeness channels. The spin transfer coefficient D_NN for associated production seems particularly sensitive to the underlying mechanism and hence useful in the context of testing the limits of meson-exchange models and the applicability of soft QCD techniques. When viewed along with available world data, the D_NN data suggest a transition regime in the energy range ~ 5-15 GeV. Possible additions to the strangeness measurements and extension to the charm sector at a higher energy (LISS-type) accelerator will be discussed.

  8. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Kennedy Space Center Director Bob Cabana, right, provides a tour for cast and crew members of the upcoming motion picture "Hidden Figures." In the background is Launch Pad 14 at Cape Canaveral Air Force Station. The pad which was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. With Cabana is Taraji P. Henson, who portrays Katherine Johnson in the film. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  9. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, members of the media participate in a news conference with key individuals from the upcoming motion picture "Hidden Figures." From the left are: Octavia Spencer, who portrays Dorothy Vaughan; Taraji P. Henson, who portrays Katherine Johnson in the film; and Janelle Monáe, who portrays Mary Jackson. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  10. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Octavia Spencer, who portrays Dorothy Vaughan in the upcoming motion picture "Hidden Figures," looks through a periscope in the blockhouse at Launch Pad 14 at Cape Canaveral Air Force Station. The pad which was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  11. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Taraji P. Henson, who portrays Katherine Johnson in the upcoming motion picture "Hidden Figures," looks through a periscope in the blockhouse at Launch Pad 14 at Cape Canaveral Air Force Station. The pad which was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  12. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, Janelle Monáe, speaks to members of the media during a news conference with other key individuals involved in the upcoming motion picture "Hidden Figures." The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson (portrayed by Monáe), three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  13. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Taraji P. Henson, who portrays Katherine Johnson in the upcoming motion picture "Hidden Figures," reads the inscription on a plaque honoring NASA astronaut John Glenn. It is located at the entrance to Launch Pad 14 at Cape Canaveral Air Force Station. It was the location of the launch of Glenn and three other astronauts who flew orbital missions during Project Mercury. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  14. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Kennedy Space Center Director Bob Cabana, right, provides a tour for cast and crew members of the upcoming motion picture "Hidden Figures." The group is near the blockhouse at Launch Pad 14 at Cape Canaveral Air Force Station. The pad which was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. To Cabana's right is Taraji P. Henson, who portrays Katherine Johnson in the film. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  15. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    In the blockhouse at Cape Canaveral Air Force Station's Launch Pad 14, Sonny Witt, director of Operations for the 45th Mission Support Group at the Cape speaks to Kennedy Space Center Director Bob Cabana along with cast and crew members of the upcoming motion picture "Hidden Figures." Pad 14 was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  16. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, Taraji P. Henson speaks to members of the media during a news conference with other key individuals involved in the upcoming motion picture "Hidden Figures." The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson (played by Henson), Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  17. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Taraji P. Henson, who portrays Katherine Johnson in the upcoming motion picture "Hidden Figures," looks at a display in the blockhouse at Launch Pad 14 at Cape Canaveral Air Force Station. The pad which was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  18. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, Ted Melfi, writer and director of the upcoming motion picture “Hidden Figures,” speaks to members of the media during a news conference with other key individuals involved in the upcoming motion picture. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  19. "Hidden Figures" Tour KSC

    NASA Image and Video Library

    2016-12-12

    Octavia Spencer, who portrays Dorothy Vaughan in the upcoming motion picture "Hidden Figures," looks at a display near Launch Pad 14 at Cape Canaveral Air Force Station. The pad, seen in the background, was the location of the launch of John Glenn and three other astronauts who flew orbital missions during Project Mercury. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  20. "Hidden Figures" Panel Discussion

    NASA Image and Video Library

    2016-12-12

    In the Press Site auditorium at the Kennedy Space Center in Florida, Pharrell Williams, musician and producer of “Hidden Figures" speaks to members of the media during a news conference with other key individuals involved in the upcoming motion picture. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  1. Hidden attractors in dynamical systems

    NASA Astrophysics Data System (ADS)

    Dudkowski, Dawid; Jafari, Sajad; Kapitaniak, Tomasz; Kuznetsov, Nikolay V.; Leonov, Gennady A.; Prasad, Awadhesh

    2016-06-01

    Complex dynamical systems, ranging from the climate, ecosystems to financial markets and engineering applications typically have many coexisting attractors. This property of the system is called multistability. The final state, i.e., the attractor on which the multistable system evolves strongly depends on the initial conditions. Additionally, such systems are very sensitive towards noise and system parameters so a sudden shift to a contrasting regime may occur. To understand the dynamics of these systems one has to identify all possible attractors and their basins of attraction. Recently, it has been shown that multistability is connected with the occurrence of unpredictable attractors which have been called hidden attractors. The basins of attraction of the hidden attractors do not touch unstable fixed points (if exists) and are located far away from such points. Numerical localization of the hidden attractors is not straightforward since there are no transient processes leading to them from the neighborhoods of unstable fixed points and one has to use the special analytical-numerical procedures. From the viewpoint of applications, the identification of hidden attractors is the major issue. The knowledge about the emergence and properties of hidden attractors can increase the likelihood that the system will remain on the most desirable attractor and reduce the risk of the sudden jump to undesired behavior. We review the most representative examples of hidden attractors, discuss their theoretical properties and experimental observations. We also describe numerical methods which allow identification of the hidden attractors.

  2. Atlas of solar hidden photon emission

    NASA Astrophysics Data System (ADS)

    Redondo, Javier

    2015-07-01

    Hidden photons, gauge bosons of a U(1) symmetry of a hidden sector, can constitute the dark matter of the universe and a smoking gun for large volume compactifications of string theory. In the sub-eV mass range, a possible discovery experiment consists on searching the copious flux of these particles emitted from the Sun in a helioscope setup à la Sikivie. In this paper, we compute in great detail the flux of HPs from the Sun, a necessary ingredient for interpreting such experiments. We provide a detailed exposition of transverse photon-HP oscillations in inhomogenous media, with special focus on resonance oscillations, which play a leading role in many cases. The region of the Sun emitting HPs resonantly is a thin spherical shell for which we justify an averaged-emission formula and which implies a distinctive morphology of the angular distribution of HPs on Earth in many cases. Low mass HPs with energies in the visible and IR have resonances very close to the photosphere where the solar plasma is not fully ionised and requires building a detailed model of solar refraction and absorption. We present results for a broad range of HP masses (from 0-1 keV) and energies (from the IR to the X-ray range), the most complete atlas of solar HP emission to date.

  3. Atlas of solar hidden photon emission

    SciTech Connect

    Redondo, Javier

    2015-07-01

    Hidden photons, gauge bosons of a U(1) symmetry of a hidden sector, can constitute the dark matter of the universe and a smoking gun for large volume compactifications of string theory. In the sub-eV mass range, a possible discovery experiment consists on searching the copious flux of these particles emitted from the Sun in a helioscope setup à la Sikivie. In this paper, we compute in great detail the flux of HPs from the Sun, a necessary ingredient for interpreting such experiments. We provide a detailed exposition of transverse photon-HP oscillations in inhomogenous media, with special focus on resonance oscillations, which play a leading role in many cases. The region of the Sun emitting HPs resonantly is a thin spherical shell for which we justify an averaged-emission formula and which implies a distinctive morphology of the angular distribution of HPs on Earth in many cases. Low mass HPs with energies in the visible and IR have resonances very close to the photosphere where the solar plasma is not fully ionised and requires building a detailed model of solar refraction and absorption. We present results for a broad range of HP masses (from 0–1 keV) and energies (from the IR to the X-ray range), the most complete atlas of solar HP emission to date.

  4. Atlas of solar hidden photon emission

    SciTech Connect

    Redondo, Javier

    2015-07-20

    Hidden photons, gauge bosons of a U(1) symmetry of a hidden sector, can constitute the dark matter of the universe and a smoking gun for large volume compactifications of string theory. In the sub-eV mass range, a possible discovery experiment consists on searching the copious flux of these particles emitted from the Sun in a helioscope setup à la Sikivie. In this paper, we compute in great detail the flux of HPs from the Sun, a necessary ingredient for interpreting such experiments. We provide a detailed exposition of transverse photon-HP oscillations in inhomogenous media, with special focus on resonance oscillations, which play a leading role in many cases. The region of the Sun emitting HPs resonantly is a thin spherical shell for which we justify an averaged-emission formula and which implies a distinctive morphology of the angular distribution of HPs on Earth in many cases. Low mass HPs with energies in the visible and IR have resonances very close to the photosphere where the solar plasma is not fully ionised and requires building a detailed model of solar refraction and absorption. We present results for a broad range of HP masses (from 0–1 keV) and energies (from the IR to the X-ray range), the most complete atlas of solar HP emission to date.

  5. Metals Sector

    EPA Pesticide Factsheets

    Find environmental regulatory information about the metals sector (NAICS 331 & 332), including NESHAPs for metal coatings, effluent guidelines for metal products, combustion compliance assistance, and information about foundry sand recycling.

  6. Hidden variables in bipartite networks.

    PubMed

    Kitsak, Maksim; Krioukov, Dmitri

    2011-08-01

    We introduce and study random bipartite networks with hidden variables. Nodes in these networks are characterized by hidden variables that control the appearance of links between node pairs. We derive analytic expressions for the degree distribution, degree correlations, the distribution of the number of common neighbors, and the bipartite clustering coefficient in these networks. We also establish the relationship between degrees of nodes in original bipartite networks and in their unipartite projections. We further demonstrate how hidden variable formalism can be applied to analyze topological properties of networks in certain bipartite network models, and verify our analytical results in numerical simulations.

  7. Hidden Magnetic Portals Around Earth

    NASA Image and Video Library

    A NASA-sponsored researcher at the University of Iowa has developed a way for spacecraft to hunt down hidden magnetic portals in the vicinity of Earth. These gateways link the magnetic field of our...

  8. Hidden Statistics of Schroedinger Equation

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2011-01-01

    Work was carried out in determination of the mathematical origin of randomness in quantum mechanics and creating a hidden statistics of Schr dinger equation; i.e., to expose the transitional stochastic process as a "bridge" to the quantum world. The governing equations of hidden statistics would preserve such properties of quantum physics as superposition, entanglement, and direct-product decomposability while allowing one to measure its state variables using classical methods.

  9. Probing leptophilic dark sectors with hadronic processes

    NASA Astrophysics Data System (ADS)

    D'Eramo, Francesco; Kavanagh, Bradley J.; Panci, Paolo

    2017-08-01

    We study vector portal dark matter models where the mediator couples only to leptons. In spite of the lack of tree-level couplings to colored states, radiative effects generate interactions with quark fields that could give rise to a signal in current and future experiments. We identify such experimental signatures: scattering of nuclei in dark matter direct detection; resonant production of lepton-antilepton pairs at the Large Hadron Collider; and hadronic final states in dark matter indirect searches. Furthermore, radiative effects also generate an irreducible mass mixing between the vector mediator and the Z boson, severely bounded by ElectroWeak Precision Tests. We use current experimental results to put bounds on this class of models, accounting for both radiatively induced and tree-level processes. Remarkably, the former often overwhelm the latter.

  10. New Caledonian crows reason about hidden causal agents

    PubMed Central

    Taylor, Alex H.; Miller, Rachael; Gray, Russell D.

    2012-01-01

    The ability to make inferences about hidden causal mechanisms underpins scientific and religious thought. It also facilitates the understanding of social interactions and the production of sophisticated tool-using behaviors. However, although animals can reason about the outcomes of accidental interventions, only humans have been shown to make inferences about hidden causal mechanisms. Here, we show that tool-making New Caledonian crows react differently to an observable event when it is caused by a hidden causal agent. Eight crows watched two series of events in which a stick moved. In the first set of events, the crows observed a human enter a hide, a stick move, and the human then leave the hide. In the second, the stick moved without a human entering or exiting the hide. The crows inspected the hide and abandoned probing with a tool for food more often after the second, unexplained series of events. This difference shows that the crows can reason about a hidden causal agent. Comparative studies with the methodology outlined here could aid in elucidating the selective pressures that led to the evolution of this cognitive ability. PMID:22988112

  11. New Caledonian crows reason about hidden causal agents.

    PubMed

    Taylor, Alex H; Miller, Rachael; Gray, Russell D

    2012-10-02

    The ability to make inferences about hidden causal mechanisms underpins scientific and religious thought. It also facilitates the understanding of social interactions and the production of sophisticated tool-using behaviors. However, although animals can reason about the outcomes of accidental interventions, only humans have been shown to make inferences about hidden causal mechanisms. Here, we show that tool-making New Caledonian crows react differently to an observable event when it is caused by a hidden causal agent. Eight crows watched two series of events in which a stick moved. In the first set of events, the crows observed a human enter a hide, a stick move, and the human then leave the hide. In the second, the stick moved without a human entering or exiting the hide. The crows inspected the hide and abandoned probing with a tool for food more often after the second, unexplained series of events. This difference shows that the crows can reason about a hidden causal agent. Comparative studies with the methodology outlined here could aid in elucidating the selective pressures that led to the evolution of this cognitive ability.

  12. Lightest Visible-Sector Supersymmetric Particle is Likely to be Unstable.

    PubMed

    Acharya, Bobby S; Ellis, Sebastian A R; Kane, Gordon L; Nelson, Brent D; Perry, Malcolm J

    2016-10-28

    We argue, based on typical properties of known solutions of string or M theory, that the lightest supersymmetric particle of the visible sector is likely to be unstable. In other words, dark matter is probably not a particle with standard model quantum numbers, such as a weakly interacting massive particle. The argument is simple and based on the typical occurrence of (a) hidden sectors, (b) interactions between the standard model (visible) sector and these hidden sectors, and (c) the lack of an argument against massive neutral hidden sector particles being lighter than the lightest visible supersymmetric particle. These conclusions do not rely on arguments such as R-parity violation.

  13. Investment strategies and hidden variables

    NASA Astrophysics Data System (ADS)

    Petroni, F.; Serva, M.

    2006-06-01

    The present study shows how the information on `hidden' market variables effects optimal investment strategies. We take the point of view of two investors, one who has access to the hidden variables and one who only knows the quotes of a given asset. Following Kelly's theory on investment strategies, the Shannon information and the doubling investment rate are quantified for both investors. Thanks to his privileged knowledge, the first investor can follow a better investment strategy. Nevertheless, the second investor can extract some of the hidden information looking at the past history of the asset variable. Unfortunately, due to the complexity of his strategy, this investor will have computational difficulties when he tries to apply it. He will than follow a simplified strategy, based only on the average sign of the last l quotes of the asset. This results have been tested with some Monte Carlo simulations.

  14. Localization of hidden Chua's attractors

    NASA Astrophysics Data System (ADS)

    Leonov, G. A.; Kuznetsov, N. V.; Vagaitsev, V. I.

    2011-06-01

    The classical attractors of Lorenz, Rossler, Chua, Chen, and other widely-known attractors are those excited from unstable equilibria. From computational point of view this allows one to use numerical method, in which after transient process a trajectory, started from a point of unstable manifold in the neighborhood of equilibrium, reaches an attractor and identifies it. However there are attractors of another type: hidden attractors, a basin of attraction of which does not contain neighborhoods of equilibria. In the present Letter for localization of hidden attractors of Chua's circuit it is suggested to use a special analytical-numerical algorithm.

  15. Rotating concave eddy current probe

    DOEpatents

    Roach, Dennis P.; Walkington, Phil; Rackow, Kirk A.; Hohman, Ed

    2008-04-01

    A rotating concave eddy current probe for detecting fatigue cracks hidden from view underneath the head of a raised head fastener, such as a buttonhead-type rivet, used to join together structural skins, such as aluminum aircraft skins. The probe has a recessed concave dimple in its bottom surface that closely conforms to the shape of the raised head. The concave dimple holds the probe in good alignment on top of the rivet while the probe is rotated around the rivet's centerline. One or more magnetic coils are rigidly embedded within the probe's cylindrical body, which is made of a non-conducting material. This design overcomes the inspection impediment associated with widely varying conductivity in fastened joints.

  16. Hidden order in spin-liquid Gd₃Ga₅O₁₂.

    PubMed

    Paddison, Joseph A M; Jacobsen, Henrik; Petrenko, Oleg A; Fernández-Díaz, Maria Teresa; Deen, Pascale P; Goodwin, Andrew L

    2015-10-09

    Frustrated magnetic materials are promising candidates for new states of matter because lattice geometry suppresses conventional magnetic dipole order, potentially allowing "hidden" order to emerge in its place. A model of a hidden-order state at the atomic scale is difficult to deduce because microscopic probes are not directly sensitive to hidden order. Here, we develop such a model of the spin-liquid state in the canonical frustrated magnet gadolinium gallium garnet (Gd3Ga5O12). We show that this state exhibits a long-range hidden order in which multipoles are formed from 10-spin loops. The order is a consequence of the interplay between antiferromagnetic spin correlations and local magnetic anisotropy, which allows it to be indirectly observed in neutron-scattering experiments. Copyright © 2015, American Association for the Advancement of Science.

  17. The hidden dragons.

    PubMed

    Zeng, Ming; Williamson, Peter J

    2003-10-01

    Most multinational corporations are fascinated with China. Carried away by the number of potential customers and the relatively cheap labor, firms seeking a presence in China have traditionally focused on selling products, setting up manufacturing facilities, or both. But they've ignored an important development: the emergence of Chinese firms as powerful rivals--in China and also in the global market. In this article, Ming Zeng and Peter Williamson describe how Chinese companies like Haier, Legend, and Pearl River Piano have quietly managed to grab market share from older, bigger, and financially stronger rivals in Asia, Europe, and the United States. Global managers tend to offer the usual explanations for why Chinese companies don't pose a threat: They aren't big enough or profitable enough to compete overseas, the managers say, and these primarily state-owned companies are ill-financed and ill-equipped for global competition. As the government's policies about the private ownership of companies changed from forbidding the practice to encouraging it, a new breed of Chinese companies evolved. The authors outline the four types of hybrid Chinese companies that are simultaneously tackling the global market. China's national champions are using their advantages as domestic leaders to build global brands. The dedicated exporters are entering foreign markets on the strength of their economies of scale. The competitive networks have taken on world markets by bringing together small, specialized companies that operate in close proximity. And the technology upstarts are using innovations developed by China's government-owned research institutes to enter emerging sectors such as biotechnology. Zeng and Williamson identify these budding multinationals, analyze their strategies, and evaluate their weaknesses.

  18. Preschoolers Search for Hidden Objects

    ERIC Educational Resources Information Center

    Haddad, Jeffrey M.; Chen, Yuping; Keen, Rachel

    2011-01-01

    The issue of whether young children use spatio-temporal information (e.g., movement of objects through time and space) and/or contact-mechanical information (e.g., interaction between objects) to search for a hidden object was investigated. To determine whether one cue can have priority over the other, a dynamic event that put these cues into…

  19. Pentaquark states with hidden charm

    NASA Astrophysics Data System (ADS)

    Bijker, Roelof

    2017-07-01

    I develop an extension of the usual three-flavor quark model to four flavors (u, d, s and c), and discuss the classification of pentaquark states with hidden charm. This work is motivated by the recent observation of such states by the LHCb Collatoration at CERN.

  20. Hidden Costs of School Construction.

    ERIC Educational Resources Information Center

    Glass, Thomas E.

    1999-01-01

    Costs that may increase the original school construction estimates include school-design inefficiency, architect fees, and costs for land, site development, technology, demolition, consultants, and security. A quality-review team can plan to avoid hidden costs and ensure that the new facility will meet instructional needs at the least possible…

  1. Preschoolers Search for Hidden Objects

    ERIC Educational Resources Information Center

    Haddad, Jeffrey M.; Chen, Yuping; Keen, Rachel

    2011-01-01

    The issue of whether young children use spatio-temporal information (e.g., movement of objects through time and space) and/or contact-mechanical information (e.g., interaction between objects) to search for a hidden object was investigated. To determine whether one cue can have priority over the other, a dynamic event that put these cues into…

  2. Hidden Rules of the Superintendency.

    ERIC Educational Resources Information Center

    Caloss, Ronald

    1999-01-01

    Effective superintendents recognize three key management precepts and their hidden rules. Administrators should avoid mixing emotion and logic, attending to detractors' emotional needs before presenting a differing viewpoint. They should be graceful under pressure, expect the unexpected, and build coalitions gradually, mindful of all community…

  3. Search for dark photons from supersymmetric hidden valleys.

    PubMed

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Andeen, T; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calfayan, P; Calpas, B; Calvet, S; Cammin, J; Carrasco-Lizarraga, M A; Carrera, E; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Cheu, E; Cho, D K; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cuplov, V; Cutts, D; Cwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; DeVaughan, K; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duflot, L; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Escalier, M; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gómez, B; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinson, A P; Heintz, U; Hensel, C; Heredia-De La Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jamin, D; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kozelov, A V; Kraus, J; Kuhl, T; Kumar, A; Kupco, A; Kurca, T; Kuzmin, V A; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, W M; Leflat, A; Lellouch, J; Li, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Mättig, P; Magerkurth, A; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Maravin, Y; Martin, B; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Mendoza, L; Menezes, D; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Mitrevski, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; Obrant, G; Ochando, C; Onoprienko, D; Orduna, J; Oshima, N; Osman, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padilla, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Popov, A V; Potter, C; Prado da Silva, W L; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, E; Strauss, M; Ströhmer, R; Strom, D; Stutte, L; Sumowidagdo, S; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Tiller, B; Tissandier, F; Titov, M; Tokmenin, V V; Torchiani, I; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; van den Berg, P J; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S; Verzocchi, M; Vilanova, D; Vint, P; Vokac, P; Voutilainen, M; Wagner, R; Wahl, H D; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, G; Weber, M; Welty-Rieger, L; Wenger, A; Wetstein, M; White, A; Wicke, D; Williams, M R J; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Xu, C; Yacoob, S; Yamada, R; Yang, W-C; Yasuda, T; Yatsunenko, Y A; Ye, Z; Yin, H; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zeitnitz, C; Zelitch, S; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zivkovic, L; Zutshi, V; Zverev, E G

    2009-08-21

    We search for a new light gauge boson, a dark photon, with the D0 experiment. In the model we consider, supersymmetric partners are pair produced and cascade to the lightest neutralinos that can decay into the hidden sector state plus either a photon or a dark photon. The dark photon decays through its mixing with a photon into fermion pairs. We therefore investigate a previously unexplored final state that contains a photon, two spatially close leptons, and large missing transverse energy. We do not observe any evidence for dark photons and set a limit on their production.

  4. Mystery of the Hidden Cosmos [Complex Dark Matter

    SciTech Connect

    Dobrescu, Bogdan A.; Lincoln, Don

    2015-06-16

    Scientists know there must be more matter in the universe than what is visible. Searches for this dark matter have focused on a single unseen particle, but decades of experiments have been unsuccessful at finding it. Exotic possibilities for dark matter are looking increasingly plausible. Rather than just one particle, dark matter could contain an entire world of particles and forces that barely interact with normal matter. Complex dark matter could form dark atoms and molecules and even clump together to make hidden galactic disks that overlap with the spiral arms of the Milky Way and other galaxies. Experiments are under way to search for evidence of such a dark sector.

  5. Recent Progress in Search for Dark Sector Signatures

    NASA Astrophysics Data System (ADS)

    Deliyergiyev, Maksym

    2016-01-01

    Many difficulties are encountered when attempting to pinpoint a common origin for several observed astrophysical anomalies, and when assessing their tension with existing exclusion limits. These include systematic uncertainties affecting the operation of the detectors, our knowledge of their response, astrophysical uncertainties, and the broad range of particle couplings that can mediate interaction with a detector target. Particularly interesting astrophysical evidence has motivated a search for dark-photon, and focused our attention on a Hidden Valleys model with a GeV-scale dark sector that produces exciting signatures. Results from recent underground experiments are also considered. There is a `light' hidden sector (dark sector), present in many models of new physics beyond the Standard Model, which contains a colorful spectrum of new particles. Recently, it has been shown that this spectrum can give rise to unique signatures at colliders when the mass scale in the hidden sector is well below a TeV; as in Hidden Valleys, Stueckelberg extensions, and Unparticle models. These physics models produce unique signatures of collimated leptons at high energies. By studying these ephemeral particles we hope to trace the history of the Universe. Our present theories lead us to believe that there is something new just around the corner, which should be accessible at the energies made available by modern colliders.

  6. Corruption in Education Sector Development: A Suggestion for Anticipatory Strategy.

    ERIC Educational Resources Information Center

    Tanaka, Shinichiro

    2001-01-01

    Proposes an anticipatory strategy that will help protect education sector development from corruption. The strategy, which may exist as a "hidden agenda" within a project, focuses on diagnosing rather than redressing a system thought to be corrupt, adopting prevention rather than punishment, informal rather than formal approaches, and…

  7. Asymmetric dark matter and the hadronic spectra of hidden QCD

    NASA Astrophysics Data System (ADS)

    Lonsdale, Stephen J.; Schroor, Martine; Volkas, Raymond R.

    2017-09-01

    The idea that dark matter may be a composite state of a hidden non-Abelian gauge sector has received great attention in recent years. Frameworks such as asymmetric dark matter motivate the idea that dark matter may have similar mass to the proton, while mirror matter and G ×G grand unified theories provide rationales for additional gauge sectors which may have minimal interactions with standard model particles. In this work we explore the hadronic spectra that these dark QCD models can allow. The effects of the number of light colored particles and the value of the confinement scale on the lightest stable state, the dark matter candidate, are examined in the hyperspherical constituent quark model for baryonic and mesonic states.

  8. Preschoolers Search For Hidden Objects

    PubMed Central

    Haddad, Jeffrey M.; Chen, Yuping; Keen, Rachel

    2011-01-01

    The issue of whether young children use spatio-temporal information (e.g., movement of objects through time and space) and / or contact-mechanical information (e.g., interaction between objects) to search for a hidden object was investigated. To determine if one cue can have priority over the other, a dynamic event was created that put these cues into conflict, with only spatio-temporal information being valid. Three-year-olds were found to use the valid spatio-temporal cue exclusively, and seemed to ignore the contact mechanical cue. Both search behavior and eye-tracking during the event support the view of a sophisticated sensitivity to the validity of a cue in indicating a target’s hidden location. PMID:21238978

  9. Controlling Dynamics of Hidden Attractors

    NASA Astrophysics Data System (ADS)

    Sharma, Pooja Rani; Shrimali, Manish Dev; Prasad, Awadhesh; Kuznetsov, N. V.; Leonov, G. A.

    Amplitude death (AD) in hidden attractors is attained with a scheme of linear augmentation. This linear control scheme is capable of stabilizing the system to a fixed point state even when the original system does not have any fixed point. Depending on the control parameter, different routes to AD such as boundary crises and Hopf bifurcation are observed. Lyapunov exponent and amplitude index are used to study the dynamical properties of the system.

  10. Supersymmetry breaking effects in the unparticle sector and conformal sequestering

    SciTech Connect

    Nakayama, Yu.

    2007-11-15

    We investigate unparticle physics with supersymmetry (SUSY). The SUSY breaking effects due to the gravity mediation induce soft masses for the SUSY unparticles and hence break the conformal invariance. The unparticle physics observable in near future experiments is only consistent if the SUSY breaking effects from the hidden sector to the standard model sector are dominated by the gauge mediation, or if the SUSY breaking effects to the unparticle sector are sufficiently sequestered. We argue that the natural realization of the latter possibility is the conformal sequestering scenario.

  11. Theory and Motivations of Dark Sector Dark Matter and Forces

    NASA Astrophysics Data System (ADS)

    Schuster, Philip

    2017-01-01

    We present the theory and motivations underlying ``dark'' or ``hidden'' sector dark matter and new force scenarios. Dark sector scenarios with sub-GeV mass scales have attracted particular attention in the past several years, motivated in part by findings from direct detection, satellite, and LHC experiments, as well as precision measurements. Moreover, these scenarios offer some of the simplest and least explored possibilities for dark matter. As such, sub-GeV dark sector scenarios have become the focus of a broad and growing international program of experiments.

  12. Constraints on hidden photons from current and future observations of CMB spectral distortions

    SciTech Connect

    Kunze, Kerstin E.; Vázquez-Mozo, Miguel Á. E-mail: Miguel.Vazquez-Mozo@cern.ch

    2015-12-01

    A variety of beyond the standard model scenarios contain very light hidden sector U(1) gauge bosons undergoing kinetic mixing with the photon. The resulting oscillation between ordinary and hidden photons leads to spectral distortions of the cosmic microwave background. We update the bounds on the mixing parameter χ{sub 0} and the mass of the hidden photon m{sub γ'} for future experiments measuring CMB spectral distortions, such as PIXIE and PRISM/COrE. For 10{sup −14} eV∼< m{sub γ'}∼< 10{sup −13} eV, we find the kinetic mixing angle χ{sub 0} has to be less than 10{sup −8} at 95% CL. These bounds are more than an order of magnitude stronger than those derived from the COBE/FIRAS data.

  13. Constraints on hidden photons from current and future observations of CMB spectral distortions

    NASA Astrophysics Data System (ADS)

    Kunze, Kerstin E.; Vázquez-Mozo, Miguel Á.

    2015-12-01

    A variety of beyond the standard model scenarios contain very light hidden sector U(1) gauge bosons undergoing kinetic mixing with the photon. The resulting oscillation between ordinary and hidden photons leads to spectral distortions of the cosmic microwave background. We update the bounds on the mixing parameter χ0 and the mass of the hidden photon mγ' for future experiments measuring CMB spectral distortions, such as PIXIE and PRISM/COrE. For 10-14 eVlesssim mγ'lesssim 10-13 eV, we find the kinetic mixing angle χ0 has to be less than 10-8 at 95% CL. These bounds are more than an order of magnitude stronger than those derived from the COBE/FIRAS data.

  14. On quantum algorithms for noncommutative hidden subgroups

    SciTech Connect

    Ettinger, M.; Hoeyer, P.

    1998-12-01

    Quantum algorithms for factoring and discrete logarithm have previously been generalized to finding hidden subgroups of finite Abelian groups. This paper explores the possibility of extending this general viewpoint to finding hidden subgroups of noncommutative groups. The authors present a quantum algorithm for the special case of dihedral groups which determines the hidden subgroup in a linear number of calls to the input function. They also explore the difficulties of developing an algorithm to process the data to explicitly calculate a generating set for the subgroup. A general framework for the noncommutative hidden subgroup problem is discussed and they indicate future research directions.

  15. Hidden attractor in smooth Chua systems

    NASA Astrophysics Data System (ADS)

    Leonov, G. A.; Kuznetsov, N. V.; Vagaitsev, V. I.

    2012-09-01

    The hidden oscillations (a basin of attraction of which does not contain neighborhoods of equilibria) have been obtained first in the 50-60s of the 20th century in automatic control systems with scalar piecewise-linear nonlinearity. This brings up the question about the excitation nature of hidden oscillations. In the present paper it is shown that hidden oscillations can exist not only in systems with piecewise-linear nonlinearity but also in smooth systems. Here the possibility of the existence of a hidden chaotic attractor in a modified Chua’s system with a smooth characteristic of nonlinear element is demonstrated.

  16. Solving the "Hidden Line" Problem

    NASA Technical Reports Server (NTRS)

    1984-01-01

    David Hedgley Jr., a mathematician at Dryden Flight Research Center, has developed an accurate computer program that considers whether a line in a graphic model of a three dimensional object should or should not be visible. The Hidden Line Computer Code, program automatically removes superfluous lines and permits the computer to display an object from specific viewpoints, just as the human eye would see it. Users include Rowland Institute for Science in Cambridge, MA, several departments of Lockheed Georgia Co., and Nebraska Public Power District (NPPD).

  17. Regulatory Information By Sector

    EPA Pesticide Factsheets

    Find environmental regulatory, compliance, & enforcement information for various business, industry and government sectors, listed by NAICS code. Sectors include agriculture, automotive, petroleum manufacturing, oil & gas extraction & other manufacturing

  18. Hidden scale invariance of metals

    NASA Astrophysics Data System (ADS)

    Hummel, Felix; Kresse, Georg; Dyre, Jeppe C.; Pedersen, Ulf R.

    2015-11-01

    Density functional theory (DFT) calculations of 58 liquid elements at their triple point show that most metals exhibit near proportionality between the thermal fluctuations of the virial and the potential energy in the isochoric ensemble. This demonstrates a general "hidden" scale invariance of metals making the condensed part of the thermodynamic phase diagram effectively one dimensional with respect to structure and dynamics. DFT computed density scaling exponents, related to the Grüneisen parameter, are in good agreement with experimental values for the 16 elements where reliable data were available. Hidden scale invariance is demonstrated in detail for magnesium by showing invariance of structure and dynamics. Computed melting curves of period three metals follow curves with invariance (isomorphs). The experimental structure factor of magnesium is predicted by assuming scale invariant inverse power-law (IPL) pair interactions. However, crystal packings of several transition metals (V, Cr, Mn, Fe, Nb, Mo, Ta, W, and Hg), most post-transition metals (Ga, In, Sn, and Tl), and the metalloids Si and Ge cannot be explained by the IPL assumption. The virial-energy correlation coefficients of iron and phosphorous are shown to increase at elevated pressures. Finally, we discuss how scale invariance explains the Grüneisen equation of state and a number of well-known empirical melting and freezing rules.

  19. Dissolved gas - the hidden saboteur

    SciTech Connect

    Magorien, V.G.

    1993-12-31

    Almost all hydraulic power components, to properly perform their tasks, rely on one basic, physical property, i.e., the incompressibility of the working fluid. Unfortunately, a frequently overlooked fluid property which frustrates this requirement is its ability to absorb, i.e., dissolve, store and give off gas. The gas is, most often but not always, air. This property is a complex one because it is a function not only of the fluid`s chemical make-up but temperature, pressure, exposed area, depth and time. In its relationshiop to aircraft landing-gear, where energy is absorbed hydraulically, this multi-faceted fluid property can be detrimental in two ways: dynamically, i.e., loss of energy absorption ability and statically, i.e., improper aircraft attitude on the ground. The pupose of this paper is to bring an awareness to this property by presenting: (1) examples of these manifestations with some empirical and practical solutions to them, (2) illustrations of this normally `hidden saboteur` at work, (3) Henry`s Dissolved Gas Law, (4) room-temperature, saturated values of dissolved gas for a number of different working fluids, (5) a description of the instrument used to obtain them, (6) some `missing elements` of the Dissolved Gas Law pertaining to absoption, (7) how static and dynamic conditions effect gas absorption and (8) some recommended solutions to prevent becoming a victim of this `hidden saboteur`

  20. Coupling the inflationary sector to matter

    NASA Astrophysics Data System (ADS)

    Kallosh, Renata; Linde, Andrei; Wrase, Timm

    2016-04-01

    We describe the coupling of matter fields to an inflationary sector of supergravity, the inflaton Φ and a stabilizer S, in models where the Kähler potential has a flat inflaton direction. Such models include, in particular, advanced versions of the hyperbolic α-attractor models with a flat inflaton direction Kähler potential, providing a good fit to the observational data. If the superpotential is at least quadratic in the matter fields U i , with restricted couplings to the inflaton sector, we prove that under certain conditions: i) The presence of the matter fields does not affect a successful inflationary evolution. ii) There are no tachyons in the matter sector during and after inflation. iii) The matter masses squared are higher than 3 H 2 during inflation. The simplest class of theories satisfying all required conditions is provided by models with a flat direction Kähler potential, and with the inflaton Φ and a stabilizer S belonging to a hidden sector, so that matter fields have no direct coupling to the inflationary sector in the Kähler potential and in the superpotential.

  1. Hidden Variable Theories and Quantum Nonlocality

    ERIC Educational Resources Information Center

    Boozer, A. D.

    2009-01-01

    We clarify the meaning of Bell's theorem and its implications for the construction of hidden variable theories by considering an example system consisting of two entangled spin-1/2 particles. Using this example, we present a simplified version of Bell's theorem and describe several hidden variable theories that agree with the predictions of…

  2. The Immorality of the Hidden Curriculum.

    ERIC Educational Resources Information Center

    Gordon, David

    1980-01-01

    Since the learning from it is mainly unconscious, the hidden curriculum is morally suspect as a violation of pupils' basic rights to decide what they wish to study and to be aware of the forces influencing them. It is the school's task to raise the hidden curriculum into pupils' consciousness. (Author/SJL)

  3. Hidden Variable Theories and Quantum Nonlocality

    ERIC Educational Resources Information Center

    Boozer, A. D.

    2009-01-01

    We clarify the meaning of Bell's theorem and its implications for the construction of hidden variable theories by considering an example system consisting of two entangled spin-1/2 particles. Using this example, we present a simplified version of Bell's theorem and describe several hidden variable theories that agree with the predictions of…

  4. Building Simple Hidden Markov Models. Classroom Notes

    ERIC Educational Resources Information Center

    Ching, Wai-Ki; Ng, Michael K.

    2004-01-01

    Hidden Markov models (HMMs) are widely used in bioinformatics, speech recognition and many other areas. This note presents HMMs via the framework of classical Markov chain models. A simple example is given to illustrate the model. An estimation method for the transition probabilities of the hidden states is also discussed.

  5. An introduction to hidden Markov models.

    PubMed

    Schuster-Böckler, Benjamin; Bateman, Alex

    2007-06-01

    This unit introduces the concept of hidden Markov models in computational biology. It describes them using simple biological examples, requiring as little mathematical knowledge as possible. The unit also presents a brief history of hidden Markov models and an overview of their current applications before concluding with a discussion of their limitations.

  6. Heating up the Galaxy with hidden photons

    SciTech Connect

    Dubovsky, Sergei; Hernández-Chifflet, Guzmán

    2015-12-29

    We elaborate on the dynamics of ionized interstellar medium in the presence of hidden photon dark matter. Our main focus is the ultra-light regime, where the hidden photon mass is smaller than the plasma frequency in the Milky Way. We point out that as a result of the Galactic plasma shielding direct detection of ultra-light photons in this mass range is especially challenging. However, we demonstrate that ultra-light hidden photon dark matter provides a powerful heating source for the ionized interstellar medium. This results in a strong bound on the kinetic mixing between hidden and regular photons all the way down to the hidden photon masses of order 10{sup −20} eV.

  7. Heating up the Galaxy with hidden photons

    SciTech Connect

    Dubovsky, Sergei; Hernández-Chifflet, Guzmán E-mail: ghc236@nyu.edu

    2015-12-01

    We elaborate on the dynamics of ionized interstellar medium in the presence of hidden photon dark matter. Our main focus is the ultra-light regime, where the hidden photon mass is smaller than the plasma frequency in the Milky Way. We point out that as a result of the Galactic plasma shielding direct detection of ultra-light photons in this mass range is especially challenging. However, we demonstrate that ultra-light hidden photon dark matter provides a powerful heating source for the ionized interstellar medium. This results in a strong bound on the kinetic mixing between hidden and regular photons all the way down to the hidden photon masses of order 10{sup −20} eV.

  8. Baryons States with Hidden Charm in the Extended Local Hidden Gauge Approach

    NASA Astrophysics Data System (ADS)

    Uchino, Toshitaka; Liang, Wei-Hong; Oset, Eulogio

    The s-wave interaction of bar{D}Λ c, bar{D}Σ c, {bar{D}}nolimits*Λ c, {bar{D}}nolimits*Σ c and bar{D}Σ c*, {bar{D}}nolimits*Σ c*, is studied within a unitary coupled channels scheme with the extended local hidden gauge approach. In addition to the Weinberg-Tomozawa term, several additional diagrams via the pion-exchange are also taken into account as box potentials. Furthermore, in order to implement the full coupled channels calculation, some of the box potentials which mix the vector-baryon and pseudoscalar-baryon sectors are extended to construct the effective transition potentials. As a result, we have observed six possible states in several angular momenta. Four of them correspond to two pairs of admixture states, two of bar{D}Σ c - {bar{D}}nolimits*Σ c with J = 1/2, and two of bar{D}Σ c* - {bar{D}}nolimits*Σ c* with J = 3/2. Moreover, we find a {bar{D}}nolimits*Σ c resonance which couples to the bar{D}Λ c channel and one spin degenerated bound state of {bar{D}}nolimits*Σ c* with J = 1/2,5/2.

  9. Baryon states with hidden charm in the extended local hidden gauge approach

    NASA Astrophysics Data System (ADS)

    Uchino, T.; Liang, Wei-Hong; Oset, E.

    2016-03-01

    The s -wave interaction of bar{D}Λ_c , bar{D} Σ_c , bar{D}^{ast}Λ_c , bar{D}^{ast}Σ_c and bar{D}Σ_c^{ast} , bar{D}^{ast}Σ_c^{ast} , is studied within a unitary coupled channels scheme with the extended local hidden gauge approach. In addition to the Weinberg-Tomozawa term, several additional diagrams via the pion exchange are also taken into account as box potentials. Furthermore, in order to implement the full coupled channels calculation, some of the box potentials which mix the vector-baryon and pseudoscalar-baryon sectors are extended to construct the effective transition potentials. As a result, we have observed six possible states in several angular momenta. Four of them correspond to two pairs of admixture states, two of bar{D}Σ_c-bar{D}^{ast}Σ_c with J = 1/2 , and two of bar{D}Σ_c^{ast} - bar{D}^{ast}Σ_c^{ast} with J = 3/2 . Moreover, we find a bar{D}^{ast}Σ_c resonance which couples to the bar{D}Λ_c channel and one spin degenerated bound state of bar{D}^{ast}Σ_c^{ast} with J = 1/2,5/2.

  10. Spectrophotometric probe

    DOEpatents

    Prather, William S.; O'Rourke, Patrick E.

    1994-01-01

    A support structure bearing at least one probe for making spectrophotometric measurements of a fluid using a source of light and a spectrophotometer. The probe includes a housing with two optical fibers and a planoconvex lens. A sleeve bearing a mirror surrounds the housing. The lens is separated from the mirror by a fixed distance, defining an interior space for receiving a volume of the fluid sample. A plurality of throughholes extending through the sleeve communicate between the sample volume and the exterior of the probe, all but one hole bearing a screen. A protective jacket surrounds the probe. A hollow conduit bearing a tube is formed in the wall of the probe for venting any air in the interior space when fluid enters. The probe is held at an acute angle so the optic fibers carrying the light to and from the probe are not bent severely on emergence from the probe.

  11. Spectrophotometric probe

    DOEpatents

    Prather, W.S.; O'Rourke, P.E.

    1994-08-02

    A support structure is described bearing at least one probe for making spectrophotometric measurements of a fluid using a source of light and a spectrophotometer. The probe includes a housing with two optical fibers and a planoconvex lens. A sleeve bearing a mirror surrounds the housing. The lens is separated from the mirror by a fixed distance, defining an interior space for receiving a volume of the fluid sample. A plurality of throughholes extending through the sleeve communicate between the sample volume and the exterior of the probe, all but one hole bearing a screen. A protective jacket surrounds the probe. A hollow conduit bearing a tube is formed in the wall of the probe for venting any air in the interior space when fluid enters. The probe is held at an acute angle so the optic fibers carrying the light to and from the probe are not bent severely on emergence from the probe. 3 figs.

  12. Stochastic thermodynamics of hidden pumps

    NASA Astrophysics Data System (ADS)

    Esposito, Massimiliano; Parrondo, Juan M. R.

    2015-05-01

    We show that a reversible pumping mechanism operating between two states of a kinetic network can give rise to Poisson transitions between these two states. An external observer, for whom the pumping mechanism is not accessible, will observe a Markov chain satisfying local detailed balance with an emerging effective force induced by the hidden pump. Due to the reversibility of the pump, the actual entropy production turns out to be lower than the coarse-grained entropy production estimated from the flows and affinities of the resulting Markov chain. Moreover, in presence of a large time scale separation between the fast-pumping dynamics and the slow-network dynamics, a finite current with zero dissipation may be produced. We make use of these general results to build a synthetase-like kinetic scheme able to reversibly produce high free-energy molecules at a finite rate and a rotatory motor achieving 100% efficiency at finite speed.

  13. Stochastic thermodynamics of hidden pumps.

    PubMed

    Esposito, Massimiliano; Parrondo, Juan M R

    2015-05-01

    We show that a reversible pumping mechanism operating between two states of a kinetic network can give rise to Poisson transitions between these two states. An external observer, for whom the pumping mechanism is not accessible, will observe a Markov chain satisfying local detailed balance with an emerging effective force induced by the hidden pump. Due to the reversibility of the pump, the actual entropy production turns out to be lower than the coarse-grained entropy production estimated from the flows and affinities of the resulting Markov chain. Moreover, in presence of a large time scale separation between the fast-pumping dynamics and the slow-network dynamics, a finite current with zero dissipation may be produced. We make use of these general results to build a synthetase-like kinetic scheme able to reversibly produce high free-energy molecules at a finite rate and a rotatory motor achieving 100% efficiency at finite speed.

  14. Finding an apprenticeship: hidden curriculum and social consequences.

    PubMed

    Goastellec, Gaële; Ruiz, Guillaume

    2015-01-01

    In Switzerland, the majority of students are oriented toward professional training after compulsory schooling. At this stage, one of the biggest challenges for them is to find an apprenticeship position. Matching supply and demand is a complex process that not only excludes some students from having direct access to professional training but also forces them to make early choices regarding their future sector of employment. So, how does one find an apprenticeship? And what do the students' descriptions of their search for apprenticeships reveal about the institutional determinants of social inequalities at play in the system? Based on 29 interviews conducted in 2014 with 23 apprentices and 6 recruiters in the Canton of Vaud, this article interrogates how the dimensions of educational and social trajectories combine to affect access to apprenticeships and are accentuated by recruiters using a "hidden curriculum" during the recruitment process. A hidden curriculum consists of knowledge and skills not taught by the educational institution but which appear decisive in obtaining an apprenticeship. By analyzing the contrasting experiences of students in their search for an apprenticeship, we identify four types of trajectories that explain different types of school-to-apprenticeship transitions. We show how these determinants are reinforced by the "hidden curriculum" of recruitment based on the soft skills of feeling, autonomy, anticipation, and reflexivity that are assessed in the context of recruitment interactions. The discussion section debates how the criteria that appear to be used to identify the "right apprentice" tend to (re)produce inequalities between students. This not only depends on their academic results but also on their social and cultural skills, their ability to anticipate their choices and, more widely, their ability to be a subject in their recruitment search. "The Subject is neither the individual, nor the self, but the work through which an

  15. Extended Friedberg-Lee hidden symmetries, quark masses, and CP violation with four generations

    NASA Astrophysics Data System (ADS)

    Bar-Shalom, Shaouly; Oaknin, David; Soni, Amarjit

    2009-07-01

    Motivated in part by the several observed anomalies involving CP asymmetries of B and Bs decays, we consider the standard model with a 4th sequential family (SM4) which seems to offer a rather simple resolution. We initially assume T-invariance by taking the up and down-quark 4×4 mass matrix to be real. Following Friedberg and Lee (FL), we then impose a hidden symmetry on the unobserved (hidden) up and down-quark SU(2) states. The hidden symmetry for four generations ensures the existence of two zero-mass eigenstates, which we take to be the (u,c) and (d,s) states in the up and down-quark sectors, respectively. Then, we simultaneously break T-invariance and the hidden symmetry by introducing two phase factors in each sector. This breaking mechanism generates the small quark masses mu, mc and md, ms, which, along with the orientation of the hidden symmetry, determine the size of CP-violation in the SM4. For illustration we choose a specific physical picture for the hidden symmetry and the breaking mechanism that reproduces the observed quark masses, mixing angles and CP-violation, and at the same time allows us to further obtain very interesting relations/predictions for the mixing angles of t and t'. For example, with this choice we get Vtd˜(Vcb/Vcd-Vts/Vus)+O(λ2) and Vt'b˜Vt'd·(Vcb/Vcd), Vtb'˜Vt'd·(Vts/Vus), implying that Vt'd>Vt'b, Vtb'. We furthermore find that the Cabibbo angle is related to the orientation of the hidden symmetry and that the key CP-violating quantity of our model at high energies, JSM4≡Im(VtbVt'b⋆Vt'b'Vtb'⋆), which is the high-energy analogue of the Jarlskog invariant of the SM, is proportional to the light-quark masses and the measured Cabibbo-Kobayashi-Maskawa quark-mixing matrix angles: |JSM4|˜A3λ5×(mu/mt+mc/mt'-md/mb+ms/mb')˜10-5, where Ã0.81 and λ=0.2257 are the Wolfenstein parameters. Other choices for the orientation of the hidden symmetry and/or the breaking mechanism may lead to different physical outcomes. A

  16. Variational Infinite Hidden Conditional Random Fields.

    PubMed

    Bousmalis, Konstantinos; Zafeiriou, Stefanos; Morency, Louis-Philippe; Pantic, Maja; Ghahramani, Zoubin

    2015-09-01

    Hidden conditional random fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An Infinite hidden conditional random field is a hidden conditional random field with a countably infinite number of hidden states, which rids us not only of the necessity to specify a priori a fixed number of hidden states available but also of the problem of overfitting. Markov chain Monte Carlo (MCMC) sampling algorithms are often employed for inference in such models. However, convergence of such algorithms is rather difficult to verify, and as the complexity of the task at hand increases the computational cost of such algorithms often becomes prohibitive. These limitations can be overcome by variational techniques. In this paper, we present a generalized framework for infinite HCRF models, and a novel variational inference approach on a model based on coupled Dirichlet Process Mixtures, the HCRF-DPM. We show that the variational HCRF-DPM is able to converge to a correct number of represented hidden states, and performs as well as the best parametric HCRFs-chosen via cross-validation-for the difficult tasks of recognizing instances of agreement, disagreement, and pain in audiovisual sequences.

  17. Results from the Solar Hidden Photon Search (SHIPS)

    SciTech Connect

    Schwarz, Matthias; Schneide, Magnus; Susol, Jaroslaw; Wiedemann, Günter; Knabbe, Ernst-Axel; Lindner, Axel; Ringwald, Andreas; Redondo, Javier E-mail: ernst-axel.knabbe@desy.de E-mail: jredondo@unizar.es E-mail: mschneide@hs.uni-hamburg.de E-mail: gwiedemann@hs.uni-hamburg.de

    2015-08-01

    We present the results of a search for transversely polarised hidden photons (HPs) with ∼ 3 eV energies emitted from the Sun. These hypothetical particles, known also as paraphotons or dark sector photons, are theoretically well motivated for example by string theory inspired extensions of the Standard Model. Solar HPs of sub-eV mass can convert into photons of the same energy (photon ↔ HP oscillations are similar to neutrino flavour oscillations). At SHIPS this would take place inside a long light-tight high-vacuum tube, which tracks the Sun. The generated photons would then be focused into a low-noise photomultiplier at the far end of the tube. Our analysis of 330 h of data (and 330 h of background characterisation) reveals no signal of photons from solar hidden photon conversion. We estimate the rate of newly generated photons due to this conversion to be smaller than 25 mHz/m{sup 2} at the 95% C.L . Using this and a recent model of solar HP emission, we set stringent constraints on χ, the coupling constant between HPs and photons, as a function of the HP mass.

  18. Results from the Solar Hidden Photon Search (SHIPS)

    NASA Astrophysics Data System (ADS)

    Schwarz, Matthias; Knabbe, Ernst-Axel; Lindner, Axel; Redondo, Javier; Ringwald, Andreas; Schneide, Magnus; Susol, Jaroslaw; Wiedemann, Günter

    2015-08-01

    We present the results of a search for transversely polarised hidden photons (HPs) with ~ 3 eV energies emitted from the Sun. These hypothetical particles, known also as paraphotons or dark sector photons, are theoretically well motivated for example by string theory inspired extensions of the Standard Model. Solar HPs of sub-eV mass can convert into photons of the same energy (photon leftrightarrow HP oscillations are similar to neutrino flavour oscillations). At SHIPS this would take place inside a long light-tight high-vacuum tube, which tracks the Sun. The generated photons would then be focused into a low-noise photomultiplier at the far end of the tube. Our analysis of 330 h of data (and 330 h of background characterisation) reveals no signal of photons from solar hidden photon conversion. We estimate the rate of newly generated photons due to this conversion to be smaller than 25 mHz/m2 at the 95% C.L . Using this and a recent model of solar HP emission, we set stringent constraints on χ, the coupling constant between HPs and photons, as a function of the HP mass.

  19. Results from the Solar Hidden Photon Search (SHIPS)

    SciTech Connect

    Schwarz, Matthias; Knabbe, Ernst-Axel; Lindner, Axel; Redondo, Javier; Ringwald, Andreas; Schneide, Magnus; Susol, Jaroslaw; Wiedemann, Günter

    2015-08-07

    We present the results of a search for transversely polarised hidden photons (HPs) with ∼3 eV energies emitted from the Sun. These hypothetical particles, known also as paraphotons or dark sector photons, are theoretically well motivated for example by string theory inspired extensions of the Standard Model. Solar HPs of sub-eV mass can convert into photons of the same energy (photon ↔ HP oscillations are similar to neutrino flavour oscillations). At SHIPS this would take place inside a long light-tight high-vacuum tube, which tracks the Sun. The generated photons would then be focused into a low-noise photomultiplier at the far end of the tube. Our analysis of 330 h of data (and 330 h of background characterisation) reveals no signal of photons from solar hidden photon conversion. We estimate the rate of newly generated photons due to this conversion to be smaller than 25 mHz/m{sup 2} at the 95% C.L. Using this and a recent model of solar HP emission, we set stringent constraints on χ, the coupling constant between HPs and photons, as a function of the HP mass.

  20. Mystery of the Hidden Cosmos [Complex Dark Matter

    DOE PAGES

    Dobrescu, Bogdan A.; Lincoln, Don

    2015-06-16

    Scientists know there must be more matter in the universe than what is visible. Searches for this dark matter have focused on a single unseen particle, but decades of experiments have been unsuccessful at finding it. Exotic possibilities for dark matter are looking increasingly plausible. Rather than just one particle, dark matter could contain an entire world of particles and forces that barely interact with normal matter. Complex dark matter could form dark atoms and molecules and even clump together to make hidden galactic disks that overlap with the spiral arms of the Milky Way and other galaxies. Experiments aremore » under way to search for evidence of such a dark sector.« less

  1. Exodus: Hidden origin of dark matter and baryons

    NASA Astrophysics Data System (ADS)

    Unwin, James

    2013-06-01

    We propose a new framework for explaining the proximity of the baryon and dark matter relic densities ΩDM ≈ 5Ω B . The scenario assumes that the number density of the observed dark matter states is generated due to decays from a second hidden sector which simultaneously generates the baryon asymmetry. In contrast to asymmetric dark matter models, the dark matter can be a real scalar or Majorana fermion and thus presents distinct phenomenology. We discuss aspects of model building and general constraints in this framework. Moreover, we argue that this scenario circumvents several of the experimental bounds which significantly constrain typical models of asymmetric dark matter. We present a simple supersymmetric implementation of this mechanism and show that it can be used to obtain the correct dark matter relic density for a bino LSP.

  2. Recent new examples of hidden attractors

    NASA Astrophysics Data System (ADS)

    Jafari, S.; Sprott, J. C.; Nazarimehr, F.

    2015-07-01

    Hidden attractors represent a new interesting topic in the chaos literature. These attractors have a basin of attraction that does not intersect with small neighborhoods of any equilibrium points. Oscillations in dynamical systems can be easily localized numerically if initial conditions from its open neighborhood lead to a long-time oscillation. This paper reviews several types of new rare chaotic flows with hidden attractors. These flows are divided into to three main groups: rare flows with no equilibrium, rare flows with a line of equilibrium points, and rare flows with a stable equilibrium. In addition we describe a novel system containing hidden attractors.

  3. The hidden structure of liquids

    NASA Astrophysics Data System (ADS)

    Ball, Philip

    2014-08-01

    From its earliest days, crystallography has been viewed as a means to probe order in matter. J. D. Bernal's work on the structure of water reframed it as a means of examining the extent to which matter can be regarded as orderly.

  4. Hidden Patterns of Light Revealed by Spitzer

    NASA Image and Video Library

    2012-06-07

    Astronomers have uncovered patterns of light that appear to be from the first stars and galaxies that formed in the universe. The light patterns were hidden within a strip of sky observed by NASA Spitzer Space Telescope.

  5. Perspective: Disclosing hidden sources of funding.

    PubMed

    Resnik, David B

    2009-09-01

    In this article, the author discusses ethical and policy issues related to the disclosure of hidden sources of funding in research. The author argues that authors have an ethical obligation to disclose hidden sources of funding and that journals should adopt policies to enforce this obligation. Journal policies should require disclosure of hidden sources of funding that authors know about and that have a direct relation to their research. To stimulate this discussion, the author describes a recent case: investigators who conducted a lung cancer screening study had received funding from a private foundation that was supported by a tobacco company, but they did not disclose this relationship to the journal. Investigators and journal editors must be prepared to deal with these issues in a manner that promotes honesty, transparency, fairness, and accountability in research. The development of well-defined, reasonable policies pertaining to hidden sources of funding can be a step in this direction.

  6. Nonstrange and strange pentaquarks with hidden charm

    NASA Astrophysics Data System (ADS)

    Anisovich, V. V.; Matveev, M. A.; Nyiri, J.; Sarantsev, A. V.; Semenova, A. N.

    2015-11-01

    Nonstrange and strange pentaquarks with hidden charm are considered as diquark-diquark-antiquark composite systems. Spin and isospin content of such exotic states is discussed and masses are evaluated.

  7. Control of multistability in hidden attractors

    NASA Astrophysics Data System (ADS)

    Sharma, P. R.; Shrimali, M. D.; Prasad, A.; Kuznetsov, N. V.; Leonov, G. A.

    2015-07-01

    Hidden attractors have a basin of attraction which is not connected with unstable equilibrium. Certain systems with hidden attractor show multistability for a range of parameter. Multistability or coexistence of different attractors in nonlinear systems often creates inconvenience and therefore, needs to be avoided to obtain a desired specific output from the system. We discuss the control of multistability in the hidden attractor through the scheme of linear augmentation, that can drive the multistable system to a monostable state. With the proper choice of control parameters a shift from multistability to monostability can be achieved. This transition from multiple attractors to a single attractor is confirmed by calculating the basin size as a measure. When a nonlinear system with hidden attractors is coupled with a linear system, two important transitions are observed with the increase of coupling strength: transition from multistability to monostability and then stabilization of newly created equilibrium point via suppression of oscillations.

  8. Hidden Tools for Life Planning and Development.

    ERIC Educational Resources Information Center

    Shepard, John W.; And Others, Eds.

    1991-01-01

    Includes "Leisureman and the Future of Life Planning" (Edwards); "Leisure: A Hidden Counseling Tool" (Zorn, Kimeldorf); "Breakthrough in Productivity" (Faulkner); "Volunteerism" (Schindler-Rainman); "Building Bridges" (Larkin, Burdick); "Religion" (Whitten); "Knowledge of…

  9. It Twins! Spitzer Finds Hidden Jet

    NASA Image and Video Library

    2011-04-04

    NASA Spitzer Space Telescope took this image of a baby star sprouting two identical jets green lines emanating from fuzzy star. The left jet was hidden behind a dark cloud, which Spitzer can see through.

  10. Hidden Tools for Life Planning and Development.

    ERIC Educational Resources Information Center

    Shepard, John W.; And Others, Eds.

    1991-01-01

    Includes "Leisureman and the Future of Life Planning" (Edwards); "Leisure: A Hidden Counseling Tool" (Zorn, Kimeldorf); "Breakthrough in Productivity" (Faulkner); "Volunteerism" (Schindler-Rainman); "Building Bridges" (Larkin, Burdick); "Religion" (Whitten); "Knowledge of…

  11. A Chaotic System with Different Families of Hidden Attractors

    NASA Astrophysics Data System (ADS)

    Pham, Viet-Thanh; Volos, Christos; Jafari, Sajad; Vaidyanathan, Sundarapandian; Kapitaniak, Tomasz; Wang, Xiong

    The presence of hidden attractors in dynamical systems has received considerable attention recently both in theory and applications. A novel three-dimensional autonomous chaotic system with hidden attractors is introduced in this paper. It is exciting that this chaotic system can exhibit two different families of hidden attractors: hidden attractors with an infinite number of equilibrium points and hidden attractors without equilibrium. Dynamical behaviors of such system are discovered through mathematical analysis, numerical simulations and circuit implementation.

  12. Hidden local symmetry and beyond

    NASA Astrophysics Data System (ADS)

    Yamawaki, Koichi

    Gerry Brown was a godfather of our hidden local symmetry (HLS) for the vector meson from the birth of the theory throughout his life. The HLS is originated from very nature of the nonlinear realization of the symmetry G based on the manifold G/H, and thus is universal to any physics based on the nonlinear realization. Here, I focus on the Higgs Lagrangian of the Standard Model (SM), which is shown to be equivalent to the nonlinear sigma model based on G/H = SU(2)L ×SU(2)R/SU(2)V with additional symmetry, the nonlinearly-realized scale symmetry. Then, the SM does have a dynamical gauge boson of the SU(2)V HLS, “SM ρ meson”, in addition to the Higgs as a pseudo-dilaton as well as the NG bosons to be absorbed in to the W and Z. Based on the recent work done with Matsuzaki and Ohki, I discuss a novel possibility that the SM ρ meson acquires kinetic term by the SM dynamics itself, which then stabilizes the skyrmion dormant in the SM as a viable candidate for the dark matter, what we call “dark SM skyrmion (DSMS)”.

  13. Hidden figures are ever present.

    PubMed

    Mens, L H; Leeuwenberg, E L

    1988-11-01

    Preference judgments about alternative interpretations of unambiguous patterns can be explained in terms of a rivalry between a preferred and a second-best interpretation (cf. Leeuwenberg & Buffart, 1983). We tested whether this second-best interpretation corresponds to a suppressed but concurrently present interpretation or whether it merely reflects an alternative view that happens to be preferred less often. Two patterns were present immediately following each other with a very short onset asynchrony: a complete pattern and one out of three possible subpatterns of it, corresponding to the best, the second best, or an odd interpretation of the complete pattern. Subjects indicated which subpattern was presented by choosing among the three subpatterns shown after each trial. The scores, corrected for response-bias effects, indicated a relative facilitation of the second-best interpretation, in agreement with its predicted "hidden" presence. This result is more in line with theories that capitalize on the quality of the finally selected representation than with processing models aimed at reaching one single solution as fast and as economically as possible.

  14. Hidden local symmetry and beyond

    NASA Astrophysics Data System (ADS)

    Yamawaki, Koichi

    Gerry Brown was a godfather of our hidden local symmetry (HLS) for the vector meson from the birth of the theory throughout his life. The HLS is originated from very nature of the nonlinear realization of the symmetry G based on the manifold G/H, and thus is universal to any physics based on the nonlinear realization. Here, I focus on the Higgs Lagrangian of the Standard Model (SM), which is shown to be equivalent to the nonlinear sigma model based on G/H = SU(2)L × SU(2)R/SU(2)V with additional symmetry, the nonlinearly-realized scale symmetry. Then, the SM does have a dynamical gauge boson of the SU(2)V HLS, "SM ρ meson", in addition to the Higgs as a pseudo-dilaton as well as the NG bosons to be absorbed in to the W and Z. Based on the recent work done with Matsuzaki and Ohki, I discuss a novel possibility that the SM ρ meson acquires kinetic term by the SM dynamics itself, which then stabilizes the skyrmion dormant in the SM as a viable candidate for the dark matter, what we call "dark SM skyrmion (DSMS)".

  15. The hidden messages managers send.

    PubMed

    McCaskey, M B

    1979-01-01

    If a manager in an organization talks about making an "end run," what is he saying? Is he seeing life in the organization as a game; is he seeing it as hazardous and maybe nominating himself for a hero role; or is he merely saying he's going all the way with a project, regardless. The truth is we don't know what he's saying. It is all too easy both to interpret the metaphors others use to fit out own meanings and to ignore the fact that metaphors have idiosyncratic meanings that should be listened to. The author describes three ways managers convey messages about themselves and the ways they see the world. He encourages the reader to see these ways--their metaphors, office settings, and body language and tones that accompany their speech--as means of communicating. Just as speech or mathematics, these are languages that can be learned. With skill in them, a manager can see or hear what is really going on when people talk, what hidden messages we are sending all the time. The author gives some hints on what to look and listen for in trying to understand others, but he warns against simplistic interpretations: all messages occur in context.

  16. Hidden symmetries of dynamics in classical and quantum physics

    NASA Astrophysics Data System (ADS)

    Cariglia, Marco

    2014-10-01

    This article reviews the role of hidden symmetries of dynamics in the study of physical systems, from the basic concepts of symmetries in phase space to the forefront of current research. Such symmetries emerge naturally in the description of physical systems as varied as nonrelativistic, relativistic, with or without gravity, classical or quantum, and are related to the existence of conserved quantities of the dynamics and integrability. In recent years their study has grown intensively, due to the discovery of nontrivial examples that apply to different types of theories and different numbers of dimensions. Applications encompass the study of integrable systems such as spinning tops, the Calogero model, systems described by the Lax equation, the physics of higher-dimensional black holes, the Dirac equation, and supergravity with and without fluxes, providing a tool to probe the dynamics of nonlinear systems.

  17. Dark radiation constraints on minicharged particles in models with a hidden photon

    SciTech Connect

    Vogel, Hendrik; Redondo, Javier E-mail: redondo@mpp.mpg.de

    2014-02-01

    We compute the thermalization of a hidden sector consisting of minicharged fermions (MCPs) and massless hidden photons in the early Universe. The precise measurement of the anisotropies of the cosmic microwave background (CMB) by Planck and the relic abundance of light nuclei produced during big bang nucleosynthesis (BBN) constrain the amount of dark radiation of this hidden sector through the effective number of neutrino species, N{sub eff}. This study presents novel and accurate predictions of dark radiation in the strongly and weakly coupled regime for a wide range of model parameters. We give the value of N{sub eff} for MCP masses between ∼ 100 keV and 10 GeV and minicharges in the range 10{sup −11}−1. Our results can be used to constrain MCPs with the current data and they are also a valuable indicator for future experimental searches, should the hint for dark radiation manifest itself in the next release of Planck's data.

  18. New hidden beauty molecules predicted by the local hidden gauge approach and heavy quark spin symmetry

    NASA Astrophysics Data System (ADS)

    Xiao, C. W.; Ozpineci, A.; Oset, E.

    2015-10-01

    Using a coupled channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-meson interaction with hidden beauty. We obtain several new states of isospin I = 0: six bound states, and weakly bound six more possible states which depend on the influence of the coupled channel effects.

  19. Limiting first-order phase transitions in dark gauge sectors from gravitational waves experiments

    NASA Astrophysics Data System (ADS)

    Addazi, Andrea

    2017-03-01

    We discuss the possibility to indirectly test first-order phase transitions of hidden sectors. We study the interesting example of a Dark Standard Model (D-SM) with a deformed parameter space in the Higgs potential. A dark electroweak phase transition can be limited from next future experiments like eLISA and DECIGO.

  20. Show Me the Invisible: Visualizing Hidden Content

    PubMed Central

    Geymayer, Thomas; Steinberger, Markus; Lex, Alexander; Streit, Marc; Schmalstieg, Dieter

    2014-01-01

    Content on computer screens is often inaccessible to users because it is hidden, e.g., occluded by other windows, outside the viewport, or overlooked. In search tasks, the efficient retrieval of sought content is important. Current software, however, only provides limited support to visualize hidden occurrences and rarely supports search synchronization crossing application boundaries. To remedy this situation, we introduce two novel visualization methods to guide users to hidden content. Our first method generates awareness for occluded or out-of-viewport content using see-through visualization. For content that is either outside the screen’s viewport or for data sources not opened at all, our second method shows off-screen indicators and an on-demand smart preview. To reduce the chances of overlooking content, we use visual links, i.e., visible edges, to connect the visible content or the visible representations of the hidden content. We show the validity of our methods in a user study, which demonstrates that our technique enables a faster localization of hidden content compared to traditional search functionality and thereby assists users in information retrieval tasks. PMID:25325078

  1. The Second International Conference on Nutrition: Implications for Hidden Hunger.

    PubMed

    Amoroso, Leslie

    2016-01-01

    The Second International Conference on Nutrition (ICN2) was jointly organized by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) and was held at the FAO Headquarters in Rome, Italy, from 19 to 21 November 2014. The ICN2 was a high-level intergovernmental meeting that focused global attention on addressing malnutrition in all its forms: undernutrition, including micronutrient deficiencies, overweight, and obesity. The ICN2 was held to specifically address the persistent and unacceptably high levels of malnutrition. Despite much progress in reducing hunger globally, 795 million people remain undernourished, over 2 billion people suffer from various micronutrient deficiencies, and an estimated 161 million children under 5 years of age are stunted, 99 million underweight, and 51 million wasted. Meanwhile, more than 600 million adults are obese. Global problems require global solutions. The ICN2 brought together national policy-makers from food, agriculture, health, education, social protection and other relevant sectors to address the complex problem of malnutrition through a multi-sectoral approach. Two outcome documents - the Rome Declaration on Nutrition and the Framework for Action - were endorsed by participating governments at the Conference, committing world leaders to establishing national policies aimed at eradicating malnutrition in all its forms and transforming food systems to make nutritious diets available to all. The Rome Declaration on Nutrition is a political statement of 10 commitments for more effective and coordinated action to improve nutrition, while the Framework for Action is a voluntary technical guide of 60 recommendations for the implementation of the political commitments. This chapter provides information on the ICN2 and its outcomes as well as follow-up activities. Emphasis is placed on the Rome Declaration on Nutrition and the Framework for Action, with special focus on hidden

  2. Central Compact Objects in Kes 79 and RCW 103 as `Hidden' Magnetars with Crustal Activity

    NASA Astrophysics Data System (ADS)

    Popov, S. B.; Kaurov, A. A.; Kaminker, A. D.

    2015-05-01

    We propose that observations of `hidden' magnetars in central compact objects can be used to probe crustal activity of neutron stars with large internal magnetic fields. Estimates based on calculations by Perna & Pons, Pons & Rea and Kaminker et al. suggest that central compact objects, which are proposed to be `hidden' magnetars, must demonstrate flux variations on the time scale of months-years. However, the most prominent candidate for the `hidden' magnetars - CXO J1852.6+0040 in Kes 79 - shows constant (within error bars) flux. This can be interpreted by lower variable crustal activity than in typical magnetars. Alternatively, CXO J1852.6+0040 can be in a high state of variable activity during the whole period of observations. Then we consider the source 1E161348 - 5055 in RCW103 as another candidate. Employing a simple 2D-modelling we argue that properties of the source can be explained by the crustal activity of the magnetar type. Thus, this object may be supplemented for the three known candidates for the `hidden' magnetars among central compact objects discussed in literature.

  3. Astrophysical Probes of New Models of Dark Matter

    NASA Astrophysics Data System (ADS)

    Zurek, Kathryn

    One of the most pressing and relevant cosmological questions is on the nature of the dark matter. I propose a comprehensive program at the boundary of astrophysics and cosmology with particle physics, focused on the question on the nature of the Dark Matter (DM). Research at the boundary of the two fields is critically important as a plethora of experiments in both particle physics and astrophysics, such as direct and indirect detection of Dark Matter (DM) by the Fermi Gamma Ray Space Telescope (FGST), AMS-02, and Cosmic Microwave Background probes such as Planck, come online. At the same time, data from the Large Hadron Collider (LHC) will probe fundamental questions about Electroweak Symmetry Breaking and its implications for astrophysics and cosmology, as concerns especially the nature of the DM and the generation of the baryon asymmetry. Physics beyond the Standard Model (SM) is required to explain the astrophysical observation that DM dominates over ordinary matter by a ratio 5:1, as we learned through WMAP, as well as large scale structure surveys. Despite lacking an understanding of the properties of the DM, its presence is crucial for the formation of structure in the universe. Particle physics provides a framework for understanding what the DM could be. This proposal centers on building new models of DM, as well as studying their signatures both in the galaxy and on earth. While particle physics has provided a few popular candidates for DM (such as the supersymmetric neutralino), whose signatures have been extensively studied in the literature, it is important to consider other theoretically motivated candidates which provide distinct signatures. This proposal focuses on such new models of DM, especially models of DM from hidden sectors. For example, recently, the PAMELA experiment has observed a rise in the ratio of positron to electron flux at high energies. The flux may likely come from astrophysical objects nearby, such as pulsars. An intriguing

  4. Hidden Bifurcations in the Multispiral Chua Attractor

    NASA Astrophysics Data System (ADS)

    Menacer, Tidjani; Lozi, René; Chua, Leon O.

    2016-12-01

    We introduce a novel method revealing hidden bifurcations in the multispiral Chua attractor in the case where the parameter of bifurcation c which determines the number of spiral is discrete. This method is based on the core idea of the genuine Leonov and Kuznetsov method for searching hidden attractors (i.e. applying homotopy and numerical continuation) but used in a very different way. Such hidden bifurcations are governed by a homotopy parameter ɛ whereas c is maintained constant. This additional parameter which is absent from the initial problem is perfectly fitted to unfold the actual structure of the multispiral attractor. We study completely the multispiral Chua attractor, generated via sine function, and check numerically our method for odd and even values of c from 1 to 12. In addition, we compare the shape of the attractors obtained for the same value of parameter ɛ while varying the parameter c.

  5. Optical probe

    DOEpatents

    Hencken, Kenneth; Flower, William L.

    1999-01-01

    A compact optical probe is disclosed particularly useful for analysis of emissions in industrial environments. The instant invention provides a geometry for optically-based measurements that allows all optical components (source, detector, rely optics, etc.) to be located in proximity to one another. The geometry of the probe disclosed herein provides a means for making optical measurements in environments where it is difficult and/or expensive to gain access to the vicinity of a flow stream to be measured. Significantly, the lens geometry of the optical probe allows the analysis location within a flow stream being monitored to be moved while maintaining optical alignment of all components even when the optical probe is focused on a plurality of different analysis points within the flow stream.

  6. Mineral Processing Sector

    EPA Pesticide Factsheets

    Find environmental regulatory and compliance information for the nonmetallic mineral processing sector (NAICS 327), including NESHAPs for asbestos and hazardous waste, and wastewater permit information.

  7. Hidden treasures - 50 km points of interests

    NASA Astrophysics Data System (ADS)

    Lommi, Matias; Kortelainen, Jaana

    2015-04-01

    Tampere is third largest city in Finland and a regional centre. During 70's there occurred several communal mergers. Nowadays this local area has both strong and diversed identity - from wilderness and agricultural fields to high density city living. Outside the city center there are interesting geological points unknown for modern city settlers. There is even a local proverb, "Go abroad to Teisko!". That is the area the Hidden Treasures -student project is focused on. Our school Tammerkoski Upper Secondary School (or Gymnasium) has emphasis on visual arts. We are going to offer our art students scientific and artistic experiences and knowledge about the hidden treasures of Teisko area and involve the Teisko inhabitants into this project. Hidden treasures - Precambrian subduction zone and a volcanism belt with dense bed of gold (Au) and arsenic (As), operating goldmines and quarries of minerals and metamorphic slates. - North of subduction zone a homogenic precambrian magmastone area with quarries, products known as Kuru Grey. - Former ashores of post-glasial Lake Näsijärvi and it's sediments enabled the developing agriculture and sustained settlement. Nowadays these ashores have both scenery and biodiversity values. - Old cattle sheds and dairy buildings made of local granite stones related to cultural stonebuilding inheritance. - Local active community of Kapee, about 100 inhabitants. Students will discover information of these "hidden" phenomena, and rendering this information trough Enviromental Art Method. Final form of this project will be published in several artistic and informative geocaches. These caches are achieved by a GPS-based special Hidden Treasures Cycling Route and by a website guiding people to find these hidden points of interests.

  8. Hidden simplicity of gauge theory amplitudes

    NASA Astrophysics Data System (ADS)

    Drummond, J. M.

    2010-11-01

    These notes were given as lectures at the CERN Winter School on Supergravity, Strings and Gauge Theory 2010. We describe the structure of scattering amplitudes in gauge theories, focussing on the maximally supersymmetric theory to highlight the hidden symmetries which appear. Using the Britto, Cachzo, Feng and Witten (BCFW) recursion relations we solve the tree-level S-matrix in \\ {N}=4 super Yang-Mills theory and describe how it produces a sum of invariants of a large symmetry algebra. We review amplitudes in the planar theory beyond tree level, describing the connection between amplitudes and Wilson loops, and discuss the implications of the hidden symmetries.

  9. NuSTAR Seeks Hidden Black Holes

    NASA Image and Video Library

    2015-07-06

    Top: An illustration of NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, in orbit. The unique school bus-long mast allows NuSTAR to focus high energy X-rays. Lower-left: A color image from NASA's Hubble Space Telescope of one of the nine galaxies targeted by NuSTAR in search of hidden black holes. Bottom-right: An artist's illustration of a supermassive black hole, actively feasting on its surroundings. The central black hole is hidden from direct view by a thick layer of encircling gas and dust. http://photojournal.jpl.nasa.gov/catalog/PIA19348

  10. Finding an apprenticeship: hidden curriculum and social consequences

    PubMed Central

    Goastellec, Gaële; Ruiz, Guillaume

    2015-01-01

    In Switzerland, the majority of students are oriented toward professional training after compulsory schooling. At this stage, one of the biggest challenges for them is to find an apprenticeship position. Matching supply and demand is a complex process that not only excludes some students from having direct access to professional training but also forces them to make early choices regarding their future sector of employment. So, how does one find an apprenticeship? And what do the students’ descriptions of their search for apprenticeships reveal about the institutional determinants of social inequalities at play in the system? Based on 29 interviews conducted in 2014 with 23 apprentices and 6 recruiters in the Canton of Vaud, this article interrogates how the dimensions of educational and social trajectories combine to affect access to apprenticeships and are accentuated by recruiters using a “hidden curriculum” during the recruitment process. A hidden curriculum consists of knowledge and skills not taught by the educational institution but which appear decisive in obtaining an apprenticeship. By analyzing the contrasting experiences of students in their search for an apprenticeship, we identify four types of trajectories that explain different types of school-to-apprenticeship transitions. We show how these determinants are reinforced by the “hidden curriculum” of recruitment based on the soft skills of feeling, autonomy, anticipation, and reflexivity that are assessed in the context of recruitment interactions. The discussion section debates how the criteria that appear to be used to identify the “right apprentice” tend to (re)produce inequalities between students. This not only depends on their academic results but also on their social and cultural skills, their ability to anticipate their choices and, more widely, their ability to be a subject in their recruitment search. “The Subject is neither the individual, nor the self, but the work through

  11. The Corporate Illiterates: The Hidden Illiterates of Silicon Valley.

    ERIC Educational Resources Information Center

    Chase, Sharon

    1991-01-01

    Describes the writing and business communication problems of college-educated workers in Silicon Valley. Discusses hidden illiterates in the universities and in the workplace. Offers solutions for professors and managers faced with the problem of hidden illiterates. (PRA)

  12. The Hidden Civic Lessons of Public and Private Schools

    ERIC Educational Resources Information Center

    Sikkink, David

    2004-01-01

    Curriculum theory has long acknowledged the presence of a hidden curriculum in schools. Whereas the formal curriculum is explicit and documented, the hidden curriculum involves those attitudes, experiences, and learnings that are largely implicit and unintended. This article compares the hidden civic lessons found in public and private schools.…

  13. Discovering Hidden Treasures with GPS Technology

    ERIC Educational Resources Information Center

    Nagel, Paul; Palmer, Roger

    2014-01-01

    "I found it!" Addison proudly proclaimed, as she used an iPhone and Global Positioning System (GPS) software to find the hidden geocache along the riverbank. Others in Lisa Bostick's fourth grade class were jealous, but there would be other geocaches to find. With the excitement of movies like "Pirates of the Caribbean" and…

  14. Expose hidden failures to prevent cascading outages

    SciTech Connect

    Phadke, A.G.; Thorp, J.S.

    1996-07-01

    This article describes how to identify lines and buses that present the greatest hazard to system reliability, and add digital equipment to supervise and control hidden failures of the associated relays. Major blackouts are rare events, but their impact can be catastrophic. A study of significant disturbances reported by NERC in the period from 1984 through 1988 indicates that protective relays are involved in one way or another in 75% of major disturbances. A common scenario is that the relay has an undetected (hidden) defect that was exposed due to the conditions created by other disturbances. For example, near-by faults, overloads, or reverse power flows expose the defective relay and cause a false trip, which exacerbates the situation. Given the importance of hidden failure modes in traditional relaying systems, intervention by computer-based rational control schemes is proposed in this article. Relays with high-vulnerability indices can be identified, and their vulnerable functions and failure modes identified. Countermeasures to reduce or eliminate the likelihood of the hidden failure of key relays can be provided.

  15. Hidden-service Statistics Reported by Relays

    DTIC Science & Technology

    2015-06-01

    Third Conference on Theory of Cryptography , TCC’06, 2006. [8] Fabienne Eigner, Aniket Kate, Matteo Maffei, Francesca Pampaloni, and Ivan Pryvalov...Challenges in protecting tor hidden services from botnet abuse. In Proceedings of Financial Cryptography and Data Security (FC’14), March 2014. [14

  16. Taking Impressions of Hidden Cavity Walls

    NASA Technical Reports Server (NTRS)

    Burley, D.; Mayer, W.

    1987-01-01

    Lightweight, portable internal-molding device makes it possible to measure radii of, or examine contours of, passageways in hidden or complicated cavities. With device, measurements made in field, without returning assemblies to shop or laboratory for inspection. Molding head expands when compressed air applied. Inflatable tubes around head perform dual sealing and aligning function.

  17. Observation of vector solitons with hidden vorticity.

    PubMed

    Izdebskaya, Yana V; Rebling, Johannes; Desyatnikov, Anton S; Kivshar, Yuri S

    2012-03-01

    This letter reports the first experimental observation, to our knowledge, of optical vector solitons composed of two incoherently coupled vortex components. We employ nematic liquid crystal to generate stable vector solitons with counterrotating vortices and hidden vorticity. In contrast, the solitons with explicit vorticity and corotating vortex components show azimuthal splitting.

  18. Hidden supersymmetry in quantum bosonic systems

    SciTech Connect

    Correa, Francisco Plyushchay, Mikhail S.

    2007-10-15

    We show that some simple well-studied quantum mechanical systems without fermion (spin) degrees of freedom display, surprisingly, a hidden supersymmetry. The list includes the bound state Aharonov-Bohm, the Dirac delta and the Poeschl-Teller potential problems, in which the unbroken and broken N = 2 supersymmetry of linear and nonlinear (polynomial) forms is revealed.

  19. Subtleties of Hidden Quantifiers in Implication

    ERIC Educational Resources Information Center

    Shipman, Barbara A.

    2016-01-01

    Mathematical conjectures and theorems are most often of the form P(x) ? Q(x), meaning ?x,P(x) ? Q(x). The hidden quantifier ?x is crucial in understanding the implication as a statement with a truth value. Here P(x) and Q(x) alone are only predicates, without truth values, since they contain unquantified variables. But standard textbook…

  20. Computerized Testing: The Hidden Figures Test.

    ERIC Educational Resources Information Center

    Jacobs, Ronald L.; And Others

    1985-01-01

    This study adapted the Hidden Figures Test for use on PLATO and determined the reliability of the computerized version compared to the paper and pencil version. Results indicate the test was successfully adapted with some modifications, and it was judged reliable although it may be measuring additional constructs. (MBR)

  1. Subtleties of Hidden Quantifiers in Implication

    ERIC Educational Resources Information Center

    Shipman, Barbara A.

    2016-01-01

    Mathematical conjectures and theorems are most often of the form P(x) ? Q(x), meaning ?x,P(x) ? Q(x). The hidden quantifier ?x is crucial in understanding the implication as a statement with a truth value. Here P(x) and Q(x) alone are only predicates, without truth values, since they contain unquantified variables. But standard textbook…

  2. Concomitant Learnings: Hidden Influences in the Classroom.

    ERIC Educational Resources Information Center

    Wallace, Sharon A., Ed.

    This bulletin contains sets of learning experiences and emphasizes the multiple effects of classroom experiences. These effects are referred to as concomitant learning or the student's affective incidental learning. In an article preceding the area materials, the teacher is identified as the classroom's most important hidden persuader, and the…

  3. Discovering Hidden Treasures with GPS Technology

    ERIC Educational Resources Information Center

    Nagel, Paul; Palmer, Roger

    2014-01-01

    "I found it!" Addison proudly proclaimed, as she used an iPhone and Global Positioning System (GPS) software to find the hidden geocache along the riverbank. Others in Lisa Bostick's fourth grade class were jealous, but there would be other geocaches to find. With the excitement of movies like "Pirates of the Caribbean" and…

  4. Computerized Testing: The Hidden Figures Test.

    ERIC Educational Resources Information Center

    Jacobs, Ronald L.; And Others

    1985-01-01

    This study adapted the Hidden Figures Test for use on PLATO and determined the reliability of the computerized version compared to the paper and pencil version. Results indicate the test was successfully adapted with some modifications, and it was judged reliable although it may be measuring additional constructs. (MBR)

  5. Hidden Messages: Instructional Materials for Investigating Culture.

    ERIC Educational Resources Information Center

    Finkelstein, Barbara, Ed.; Eder, Elizabeth K., Ed.

    This book, intended to be used in the middle and high school classroom, provides teachers with unique ideas and lesson plans for exploring culture and adding a multicultural perspective to diverse subjects. "Hidden messages" are the messages of culture that are entwined in everyday lives, but which are seldom recognized or appreciated…

  6. Hidden Transcripts of Flight Attendant Resistance.

    ERIC Educational Resources Information Center

    Murphy, Alexandra G.

    1998-01-01

    Analyzes (using flight attendants) hidden transcripts--interactions, stories, myths, and rituals in which employees participate beyond direct observation--to provide an avenue to identify resistance and change in the organizing process. Challenges the outdated ideal of transmissional meaning, questions organizational power by including the…

  7. Registration of 'Hidden Valley' meadow fescue

    USDA-ARS?s Scientific Manuscript database

    'Hidden Valley' (Reg. No. CV-xxxx, PI xxxxxx) meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.; syn. Festuca pratensis Huds.; syn. Lolium pratense (Huds.) Darbysh.] is a synthetic population originating from 561 parental genotypes. The original germplasm is of unknown central or northern Europ...

  8. A Hidden Minority Amidst White Privilege

    ERIC Educational Resources Information Center

    Singer, Miriam J.

    2008-01-01

    It seems rather amusing to say that the author belongs to a minority, no less a hidden minority. After all, at first glance, she appears to be just another white girl (or woman). She grew up in the mid-west in a predominantly white community, middle class, and well educated. The paradox comes in their definition of minority. Today, as they seek to…

  9. The hidden consequences of fire suppression

    Treesearch

    Carol Miller

    2012-01-01

    Wilderness managers need a way to quantify and monitor the effects of suppressing lightning-caused wildfires, which can alter natural fire regimes, vegetation, and habitat. Using computerized models of fire spread, weather, and fuels, it is now possible to quantify many of the hidden consequences of fire suppression. Case study watersheds in Yosemite and Sequoia-Kings...

  10. The enigma of "hidden" traumatic brain injury.

    PubMed

    Gordon, W A; Brown, M; Sliwinski, M; Hibbard, M R; Patti, N; Weiss, M J; Kalinsky, R; Sheerer, M

    1998-12-01

    To examine individuals with "hidden" traumatic brain injury (TBI), defined in this study as those who sustained a blow to the head, with altered mental status, and experienced a substantial number of the cognitive, behavioral, and emotional sequelae typically associated with brain injury but did not make the causal connection between the injury and its consequences. Comparison of four groups of individuals matched for age, gender, years of education, and duration of loss of consciousness. This study of hidden TBI followed the identification of 143 individuals who, within a larger study of people with TBI who live in the community, identified themselves as "nondisabled" (they were to be part of the comparison sample) but who had experienced a blow to the head that left them at minimum dazed and confused. 21 of these 143 individuals also reported large numbers of symptoms (eg, headaches, memory problems) associated with TBI. This group (Hidden TBI-High Symptoms group) was compared to three other matched samples: one with known TBI (Known Mild TBI group) and one with no disability (No Disability group) (both of which were drawn from the larger study), and one group of individuals who identified themselves as having no disability but who had experienced a blow to the head that resulted in a few symptoms (Head Trauma-Low Symptoms group). All study participants were administered an interview that incorporated several existing instruments documenting levels of reported symptoms, emotional well-being/distress, and vocational/social handicaps. The Hidden TBI-High Symptoms group was found to be similar to the Known Mild TBI group in terms of the number and types of symptoms experienced, whereas the Head Trauma-Low Symptoms group was similar in this respect to the No Disability group. The two former groups also evidenced high levels of emotional distress, whereas the two latter groups did not. However, on measures of handicap, the Hidden TBI-High Symptoms and Head Trauma

  11. General view of Sector One Substation with Sector One transmitter ...

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

    General view of Sector One Substation with Sector One transmitter array to right - Over-the-Horizon Backscatter Radar Network, Moscow Radar Site Transmit Sector One Substation, At the end of Steam Road, Moscow, Somerset County, ME

  12. Synthetic gene design with a large number of hidden stops.

    PubMed

    Phan, Vinhthuy; Saha, Sudip; Pandey, Ashutosh; Wong, Tit-Yee

    2010-01-01

    Hidden stops are nucleotide triples TAA, TAG and TGA that appear on the second and third reading frames of a protein coding gene. Recent studies suggested the important role of hidden stops in preventing misread of mRNA. We study the problem of designing protein-encoding genes with large number of hidden stops under several biological constraints. With simple constraints, redesigned genes have provable maximal number of hidden stops. With more complex constraints, redesigned genes still have many more hidden stops than wild-type genes. We showed that redesigned genes have a distinct positional advantage in assisting early termination of frame-shifts.

  13. Three Dimensional Sector Design with Optimal Number of Sectors

    NASA Technical Reports Server (NTRS)

    Xue, Min

    2010-01-01

    In the national airspace system, sectors get overloaded due to high traffic demand and inefficient airspace designs. Overloads can be eliminated in some cases by redesigning sector boundaries. This paper extends the Voronoi-based sector design method by automatically selecting the number of sectors, allowing three-dimensional partitions, and enforcing traffic pattern conformance. The method was used to design sectors at Fort-Worth and Indianapolis centers for current traffic scenarios. Results show that new designs can eliminate overloaded sectors, although not in all cases, reduce the number of necessary sectors, and conform to major traffic patterns. Overall, the new methodology produces enhanced and efficient sector designs.

  14. Pollution Probe.

    ERIC Educational Resources Information Center

    Chant, Donald A.

    This book is written as a statement of concern about pollution by members of Pollution Probe, a citizens' anti-pollution group in Canada. Its purpose is to create public awareness and pressure for the eventual solution to pollution problems. The need for effective government policies to control the population explosion, conserve natural resources,…

  15. Pollution Probe.

    ERIC Educational Resources Information Center

    Chant, Donald A.

    This book is written as a statement of concern about pollution by members of Pollution Probe, a citizens' anti-pollution group in Canada. Its purpose is to create public awareness and pressure for the eventual solution to pollution problems. The need for effective government policies to control the population explosion, conserve natural resources,…

  16. Buildings Sector Analysis

    SciTech Connect

    Hostick, Donna J.; Nicholls, Andrew K.; McDonald, Sean C.; Hollomon, Jonathan B.

    2005-08-01

    A joint NREL, ORNL, and PNNL team conducted market analysis to help inform DOE/EERE's Weatherization and Intergovernmental Program planning and management decisions. This chapter presents the results of the market analysis for the Buildings sector.

  17. Construction Sector (NAICS 23)

    EPA Pesticide Factsheets

    Find environmental regulatory information for the construction sector, including the construction of buildings or engineering projects. This includes RCRA information for hazardous waste, refrigeration compliance, asbestos, effluent guidelines & lead laws

  18. Estimating Neuronal Ageing with Hidden Markov Models

    NASA Astrophysics Data System (ADS)

    Wang, Bing; Pham, Tuan D.

    2011-06-01

    Neuronal degeneration is widely observed in normal ageing, meanwhile the neurode-generative disease like Alzheimer's disease effects neuronal degeneration in a faster way which is considered as faster ageing. Early intervention of such disease could benefit subjects with potentials of positive clinical outcome, therefore, early detection of disease related brain structural alteration is required. In this paper, we propose a computational approach for modelling the MRI-based structure alteration with ageing using hidden Markov model. The proposed hidden Markov model based brain structural model encodes intracortical tissue/fluid distribution using discrete wavelet transformation and vector quantization. Further, it captures gray matter volume loss, which is capable of reflecting subtle intracortical changes with ageing. Experiments were carried out on healthy subjects to validate its accuracy and robustness. Results have shown its ability of predicting the brain age with prediction error of 1.98 years without training data, which shows better result than other age predition methods.

  19. Hidden process models for animal population dynamics.

    PubMed

    Newman, K B; Buckland, S T; Lindley, S T; Thomas, L; Fernández, C

    2006-02-01

    Hidden process models are a conceptually useful and practical way to simultaneously account for process variation in animal population dynamics and measurement errors in observations and estimates made on the population. Process variation, which can be both demographic and environmental, is modeled by linking a series of stochastic and deterministic subprocesses that characterize processes such as birth, survival, maturation, and movement. Observations of the population can be modeled as functions of true abundance with realistic probability distributions to describe observation or estimation error. Computer-intensive procedures, such as sequential Monte Carlo methods or Markov chain Monte Carlo, condition on the observed data to yield estimates of both the underlying true population abundances and the unknown population dynamics parameters. Formulation and fitting of a hidden process model are demonstrated for Sacramento River winter-run chinook salmon (Oncorhynchus tshawytsha).

  20. Hidden variables and nonlocality in quantum mechanics

    NASA Astrophysics Data System (ADS)

    Hemmick, Douglas Lloyd

    1997-05-01

    Most physicists hold a skeptical attitude toward a 'hidden variables' interpretation of quantum theory, despite David Bohm's successful construction of such a theory and John S. Bell's strong arguments in favor of the idea. The first reason for doubt concerns certain mathematical theorems (von Neumann's, Gleason's, Kochen and Specker's, and Bell's) which can be applied to the hidden variables issue. These theorems are often credited with proving that hidden variables are indeed 'impossible', in the sense that they cannot replicate the predictions of quantum mechanics. Many who do not draw such a strong conclusion nevertheless accept that hidden variables have been shown to exhibit prohibitively complicated features. The second concern is that the most sophisticated example of a hidden variables theory-that of David Bohm-exhibits non-locality, i.e., consequences of events at one place can propagate to other places instantaneously. However, neither the mathematical theorems in question nor the attribute of nonlocality detract from the importance of a hidden variables interpretation of quantum theory. Nonlocality is present in quantum mechanics itself, and is a required characteristic of any theory that agrees with the quantum mechanical predictions. We first discuss the earliest analysis of hidden variables-that of von Neumann's theorem-and review John S. Bell's refutation of von Neumann's 'impossibility proof'. We recall and elaborate on Bell's arguments regarding the theorems of Gleason, and Kochen and Specker. According to Bell, these latter theorems do not imply that hidden variables interpretations are untenable, but instead that such theories must exhibit contextuality, i.e., they must allow for the dependence of measurement results on the characteristics of both measured system and measuring apparatus. We demonstrate a new way to understand the implications of both Gleason's theorem and Kochen and Specker's theorem by noting that they prove a result we call

  1. Biofortification for combating 'hidden hunger' for iron.

    PubMed

    Murgia, Irene; Arosio, Paolo; Tarantino, Delia; Soave, Carlo

    2012-01-01

    Micronutrient deficiencies are responsible for so-called 'hidden undernutrition'. In particular, iron (Fe) deficiency adversely affects growth, immune function and can cause anaemia. However, supplementation of iron can exacerbate infectious diseases and current policies of iron therapy carefully evaluate the risks and benefits of these interventions. Here we review the approaches of biofortification of valuable crops for reducing 'hidden undernutrition' of iron in the light of the latest nutritional and medical advances. The increase of iron and prebiotics in edible parts of plants is expected to improve health, whereas the reduction of phytic acid concentration, in crops valuable for human diet, might be less beneficial for the developed countries, or for the developing countries exposed to endemic infections.

  2. Unveiling Hidden Unstructured Regions in Process Models

    NASA Astrophysics Data System (ADS)

    Polyvyanyy, Artem; García-Bañuelos, Luciano; Weske, Mathias

    Process models define allowed process execution scenarios. The models are usually depicted as directed graphs, with gateway nodes regulating the control flow routing logic and with edges specifying the execution order constraints between tasks. While arbitrarily structured control flow patterns in process models complicate model analysis, they also permit creativity and full expressiveness when capturing non-trivial process scenarios. This paper gives a classification of arbitrarily structured process models based on the hierarchical process model decomposition technique. We identify a structural class of models consisting of block structured patterns which, when combined, define complex execution scenarios spanning across the individual patterns. We show that complex behavior can be localized by examining structural relations of loops in hidden unstructured regions of control flow. The correctness of the behavior of process models within these regions can be validated in linear time. These observations allow us to suggest techniques for transforming hidden unstructured regions into block-structured ones.

  3. Hidden geometric correlations in real multiplex networks

    NASA Astrophysics Data System (ADS)

    Kleineberg, Kaj-Kolja; Boguñá, Marián; Ángeles Serrano, M.; Papadopoulos, Fragkiskos

    2016-11-01

    Real networks often form interacting parts of larger and more complex systems. Examples can be found in different domains, ranging from the Internet to structural and functional brain networks. Here, we show that these multiplex systems are not random combinations of single network layers. Instead, they are organized in specific ways dictated by hidden geometric correlations between the layers. We find that these correlations are significant in different real multiplexes, and form a key framework for answering many important questions. Specifically, we show that these geometric correlations facilitate the definition and detection of multidimensional communities, which are sets of nodes that are simultaneously similar in multiple layers. They also enable accurate trans-layer link prediction, meaning that connections in one layer can be predicted by observing the hidden geometric space of another layer. And they allow efficient targeted navigation in the multilayer system using only local knowledge, outperforming navigation in the single layers only if the geometric correlations are sufficiently strong.

  4. Hidden Neuronal Correlations in Cultured Networks

    NASA Astrophysics Data System (ADS)

    Segev, Ronen; Baruchi, Itay; Hulata, Eyal; Ben-Jacob, Eshel

    2004-03-01

    Utilization of a clustering algorithm on neuronal spatiotemporal correlation matrices recorded during a spontaneous activity of in vitro networks revealed the existence of hidden correlations: the sequence of synchronized bursting events (SBEs) is composed of statistically distinguishable subgroups each with its own distinct pattern of interneuron spatiotemporal correlations. These findings hint that each of the SBE subgroups can serve as a template for coding, storage, and retrieval of a specific information.

  5. The Hidden Gifts of Quiet Kids

    ERIC Educational Resources Information Center

    Trierweiler, Hannah

    2006-01-01

    The author relates that she was an introvert child. It has always taken her time and energy to find her place in a group. As a grown-up, she still needed quiet time to regroup during a busy day. In this article, the author presents an interview with Marti Olsen Laney, author of "The Hidden Gifts of the Introverted Child." During the interview,…

  6. Laparoscopic task recognition using Hidden Markov Models.

    PubMed

    Dosis, Aristotelis; Bello, Fernando; Gillies, Duncan; Undre, Shabnam; Aggarwal, Rajesh; Darzi, Ara

    2005-01-01

    Surgical skills assessment has been paid increased attention over the last few years. Stochastic models such as Hidden Markov Models have recently been adapted to surgery to discriminate levels of expertise. Based on our previous work combining synchronized video and motion analysis we present preliminary results of a HMM laparoscopic task recognizer which aims to model hand manipulations and to identify and recognize simple surgical tasks.

  7. Hidden quasars in ultraluminous infared galaxies

    SciTech Connect

    Brotherton, M S; Stanford, S A; Tran, H; van Breugel, W

    1998-08-27

    Abstract. Many ultraluminous infrared galaxies (ULIRGS) are pow- ered by quasars hidden in the center, but many are also powered by starbursts. A simply diagnostic diagram is proposed that can iden- tify obscured quasars in ULIRGs by their high-ionization emission lines ([O III]λ5007/Hβ ≳ 5), and "warm" IR color (ƒ2560 ≳ 0.25).

  8. "Hidden" social networks in behavior change interventions.

    PubMed

    Hunter, Ruth F; McAneney, Helen; Davis, Michael; Tully, Mark A; Valente, Thomas W; Kee, Frank

    2015-03-01

    We investigated whether "hidden" (or unobserved) social networks were evident in a 2011 physical activity behavior change intervention in Belfast, Northern Ireland. Results showed evidence of unobserved social networks in the intervention and illustrated how the network evolved over short periods and affected behavior. Behavior change interventions should account for the interaction among participants (i.e., social networks) and how such interactions affect intervention outcome.

  9. Killing and letting die: hidden value assumptions.

    PubMed

    Atkinson, G

    1983-01-01

    In this paper I argue for several related theses: first, that the distinction between killing and letting die, as it is drawn by ordinary persons in ordinary contexts, is more complex than is generally understood; second, that the key feature of this complexity lies in the presence of a hidden normative component in what appears to be a straightforwardly descriptive distinction; and, third, that this complexity renders the killing/letting die distinction an inadequate and hazardous guide for moral reasoning.

  10. Nonlinear realization and hidden local symmetries

    NASA Astrophysics Data System (ADS)

    Bando, Masako; Kugo, Taichiro; Yamawaki, Koichi

    1988-07-01

    The idea of dynamical gauge bosons of hidden local symmetries in nonlinear sigma models is reviewed. Starting with a fresh look at the Goldstone theorem and low energy theorems, we present a modern review of the general theory of nonlinear realization both in nonsupersymmetric and supersymmetric cases. We then show that any nonlinear sigma model based on the manifold G/ H is gauge equivalent to a “linear” model possessing a Gglobal × Hlocal symmetry, Hlocal being a hidden local symmetry. The corresponding supersymmetric formulation is also presented. The above gauge equivalence can be extended to a model having a larger symmetry Gglobal × Glocal. Also reviewed are dynamical calculatio ns showing that in some two-, three- and four-dimensional models, the gauge bosons of the hidden local symmetries acquire the kinetic terms via quantum effects, thus becoming “dynamical”. We suggest that such a dynamical gauge boson may be a rather common phenomenon realized in Nature. As a realistic example, we examine the QCD case where we identify the vector mesons (ϱ,ω,ф,K ∗) with the dynamical gauge bosons of the hidden U(3) v local symmetry in the U(3) L × U(3) R/U(3) V nonlinear sigma model. The totality of the vector meson phenomenology seems to support our basic idea. The axial-vector mesons are also incorporated into our framework. Also given is a brief sketch of some applications of this formalism to unified models beyond the standard model, such as technicolor, composite W/Z boson and supergravity models.

  11. Non-statistically populated autoionizing levels of Li-like carbon: Hidden-crossings

    SciTech Connect

    Deveney, E.F.; Krause, H.F.; Jones, N.L.

    1995-12-31

    The intensities of the Auger-electron lines from autoionizing (AI) states of Li-like (1s2s2l) configurations excited in ion-atom collisions vary as functions of the collision parameters such as, for example, the collision velocity. A statistical population of the three-electron levels is at best incomplete and underscores the intricate dynamical development of the electronic states. The authors compare several experimental studies to calculations using ``hidden-crossing`` techniques to explore some of the details of these Auger-electron intensity variation phenomena. The investigations show promising results suggesting that Auger-electron intensity variations can be used to probe collision dynamics.

  12. Extracting hidden messages in steganographic images

    DOE PAGES

    Quach, Tu-Thach

    2014-07-17

    The eventual goal of steganalytic forensic is to extract the hidden messages embedded in steganographic images. A promising technique that addresses this problem partially is steganographic payload location, an approach to reveal the message bits, but not their logical order. It works by finding modified pixels, or residuals, as an artifact of the embedding process. This technique is successful against simple least-significant bit steganography and group-parity steganography. The actual messages, however, remain hidden as no logical order can be inferred from the located payload. This paper establishes an important result addressing this shortcoming: we show that the expected mean residualsmore » contain enough information to logically order the located payload provided that the size of the payload in each stego image is not fixed. The located payload can be ordered as prescribed by the mean residuals to obtain the hidden messages without knowledge of the embedding key, exposing the vulnerability of these embedding algorithms. We provide experimental results to support our analysis.« less

  13. Extracting hidden messages in steganographic images

    SciTech Connect

    Quach, Tu-Thach

    2014-07-17

    The eventual goal of steganalytic forensic is to extract the hidden messages embedded in steganographic images. A promising technique that addresses this problem partially is steganographic payload location, an approach to reveal the message bits, but not their logical order. It works by finding modified pixels, or residuals, as an artifact of the embedding process. This technique is successful against simple least-significant bit steganography and group-parity steganography. The actual messages, however, remain hidden as no logical order can be inferred from the located payload. This paper establishes an important result addressing this shortcoming: we show that the expected mean residuals contain enough information to logically order the located payload provided that the size of the payload in each stego image is not fixed. The located payload can be ordered as prescribed by the mean residuals to obtain the hidden messages without knowledge of the embedding key, exposing the vulnerability of these embedding algorithms. We provide experimental results to support our analysis.

  14. Hidden Markov Model Analysis of Multichromophore Photobleaching

    PubMed Central

    Messina, Troy C.; Kim, Hiyun; Giurleo, Jason T.; Talaga, David S.

    2007-01-01

    The interpretation of single-molecule measurements is greatly complicated by the presence of multiple fluorescent labels. However, many molecular systems of interest consist of multiple interacting components. We investigate this issue using multiply labeled dextran polymers that we intentionally photobleach to the background on a single-molecule basis. Hidden Markov models allow for unsupervised analysis of the data to determine the number of fluorescent subunits involved in the fluorescence intermittency of the 6-carboxy-tetramethylrhodamine labels by counting the discrete steps in fluorescence intensity. The Bayes information criterion allows us to distinguish between hidden Markov models that differ by the number of states, that is, the number of fluorescent molecules. We determine information-theoretical limits and show via Monte Carlo simulations that the hidden Markov model analysis approaches these theoretical limits. This technique has resolving power of one fluorescing unit up to as many as 30 fluorescent dyes with the appropriate choice of dye and adequate detection capability. We discuss the general utility of this method for determining aggregation-state distributions as could appear in many biologically important systems and its adaptability to general photometric experiments. PMID:16913765

  15. Thermal dark matter from a highly decoupled sector

    SciTech Connect

    Berlin, Asher; Hooper, Dan; Krnjaic, Gordan

    2016-11-17

    It has recently been shown that if the dark matter is in thermal equilibrium with a sector that is highly decoupled from the Standard Model, it can freeze out with an acceptable relic abundance, even if the dark matter is as heavy as ~1–100 PeV. In such scenarios, both the dark and visible sectors are populated after inflation, but with independent temperatures. The lightest particle in the dark sector will be generically long-lived and can come to dominate the energy density of the Universe. Upon decaying, these particles can significantly reheat the visible sector, diluting the abundance of dark matter and thus allowing for dark matter particles that are much heavier than conventional WIMPs. In this study, we present a systematic and pedagogical treatment of the cosmological history in this class of models, emphasizing the simplest scenarios in which a dark matter candidate annihilates into hidden sector particles which then decay into visible matter through the vector, Higgs, or lepton portals. In each case, we find ample parameter space in which very heavy dark matter particles can provide an acceptable thermal relic abundance. We also discuss possible extensions of models featuring these dynamics.

  16. Thermal dark matter from a highly decoupled sector

    DOE PAGES

    Berlin, Asher; Hooper, Dan; Krnjaic, Gordan

    2016-11-17

    It has recently been shown that if the dark matter is in thermal equilibrium with a sector that is highly decoupled from the Standard Model, it can freeze out with an acceptable relic abundance, even if the dark matter is as heavy as ~1–100 PeV. In such scenarios, both the dark and visible sectors are populated after inflation, but with independent temperatures. The lightest particle in the dark sector will be generically long-lived and can come to dominate the energy density of the Universe. Upon decaying, these particles can significantly reheat the visible sector, diluting the abundance of dark mattermore » and thus allowing for dark matter particles that are much heavier than conventional WIMPs. In this study, we present a systematic and pedagogical treatment of the cosmological history in this class of models, emphasizing the simplest scenarios in which a dark matter candidate annihilates into hidden sector particles which then decay into visible matter through the vector, Higgs, or lepton portals. In each case, we find ample parameter space in which very heavy dark matter particles can provide an acceptable thermal relic abundance. We also discuss possible extensions of models featuring these dynamics.« less

  17. Thermal dark matter from a highly decoupled sector

    NASA Astrophysics Data System (ADS)

    Berlin, Asher; Hooper, Dan; Krnjaic, Gordan

    2016-11-01

    It has recently been shown that if the dark matter is in thermal equilibrium with a sector that is highly decoupled from the Standard Model, it can freeze out with an acceptable relic abundance, even if the dark matter is as heavy as ˜1 - 100 PeV . In such scenarios, both the dark and visible sectors are populated after inflation, but with independent temperatures. The lightest particle in the dark sector will be generically long-lived and can come to dominate the energy density of the Universe. Upon decaying, these particles can significantly reheat the visible sector, diluting the abundance of dark matter and thus allowing for dark matter particles that are much heavier than conventional WIMPs. In this paper, we present a systematic and pedagogical treatment of the cosmological history in this class of models, emphasizing the simplest scenarios in which a dark matter candidate annihilates into hidden sector particles which then decay into visible matter through the vector, Higgs, or lepton portals. In each case, we find ample parameter space in which very heavy dark matter particles can provide an acceptable thermal relic abundance. We also discuss possible extensions of models featuring these dynamics.

  18. Hidden gauged U (1 ) model: Unifying scotogenic neutrino and flavor dark matter

    NASA Astrophysics Data System (ADS)

    Yu, Jiang-Hao

    2016-06-01

    In both scotogenic neutrino and flavor dark matter models, the dark sector communicates with the standard model fermions via Yukawa portal couplings. We propose an economic scenario where the scotogenic neutrino and a flavored mediator share the same inert Higgs doublet and all are charged under a hidden gauged U (1 ) symmetry. The dark Z2 symmetry in the dark sector is regarded as the remnant of this hidden U (1 ) symmetry breaking. In particular, we investigate a dark U (1 )D [and also U (1 )B-L] model which unifies the scotogenic neutrino and top-flavored mediator. Thus dark tops and dark neutrinos are the standard model fermion partners, and the dark matter could be the inert Higgs or the lightest dark neutrino. We note that this model has rich collider signatures on dark tops, the inert Higgs and the Z' gauge boson. Moreover, the scalar associated to the U (1 )D [and also U (1 )B -L ] symmetry breaking could explain the 750 GeV diphoton excess reported by ATLAS and CMS recently.

  19. Microwave background constraints on mixing of photons with hidden photons

    SciTech Connect

    Mirizzi, Alessandro; Redondo, Javier; Sigl, Guenter E-mail: javier.redondo@desy.de

    2009-03-15

    Various extensions of the Standard Model predict the existence of hidden photons kinetically mixing with the ordinary photon. This mixing leads to oscillations between photons and hidden photons, analogous to the observed oscillations between different neutrino flavors. In this context, we derive new bounds on the photon-hidden photon mixing parameters using the high precision cosmic microwave background spectral data collected by the Far Infrared Absolute Spectrophotometer instrument on board of the Cosmic Background Explorer. Requiring the distortions of the CMB induced by the photon-hidden photon mixing to be smaller than experimental upper limits, this leads to a bound on the mixing angle {chi}{sub 0} {approx}< 10{sup -7}-10{sup -5} for hidden photon masses between 10{sup -14} eV and 10{sup -7} eV. This low-mass and low-mixing region of the hidden photon parameter space was previously unconstrained.

  20. Sector-scanning echocardiography

    NASA Technical Reports Server (NTRS)

    Henry, W. L.; Griffith, J. M.

    1975-01-01

    The mechanical sector scanner is described in detail, and its clinical application is discussed. Cross sectional images of the heart are obtained in real time using this system. The sector scanner has three major components: (a) hand held scanner, (b) video display, and (c) video recorder. The system provides diagnostic information in a wide spectrum of cardiac diseases, and it quantitates the severity of mitral stenosis by measurement of the mitral valve orifice area in diagnosing infants, children and adults with cyanotic congenital heart disease.

  1. Sector-scanning echocardiography

    NASA Technical Reports Server (NTRS)

    Henry, W. L.; Griffith, J. M.

    1975-01-01

    The mechanical sector scanner is described in detail, and its clinical application is discussed. Cross sectional images of the heart are obtained in real time using this system. The sector scanner has three major components: (a) hand held scanner, (b) video display, and (c) video recorder. The system provides diagnostic information in a wide spectrum of cardiac diseases, and it quantitates the severity of mitral stenosis by measurement of the mitral valve orifice area in diagnosing infants, children and adults with cyanotic congenital heart disease.

  2. Hidden Attractors and Dynamical Behaviors in an Extended Rikitake System

    NASA Astrophysics Data System (ADS)

    Wei, Zhouchao; Zhang, Wei; Wang, Zhen; Yao, Minghui

    In this paper, an extended Rikitake system is studied. Several issues, such as Hopf bifurcation, coexistence of stable equilibria and hidden attractor, and dynamics analysis at infinity are investigated either analytically or numerically. Especially, by a simple linear transformation, the wide range of hidden attractors is noticed, and the Lyapunov exponents diagram is given. The obtained results show that the unstable periodic solution generated by Hopf bifurcation leads to the hidden attractor. The existence of hidden attractors that may render the system's behavior unpredictable not only depends on the value of system parameters but also on the value of initial conditions. The phenomena are important and potentially problematic in engineering applications.

  3. Hidden photons in Aharonov-Bohm-type experiments

    NASA Astrophysics Data System (ADS)

    Arias, Paola; Diaz, Christian; Diaz, Marco Aurelio; Jaeckel, Joerg; Koch, Benjamin; Redondo, Javier

    2016-07-01

    We discuss the Aharonov-Bohm effect in the presence of hidden photons kinetically mixed with the ordinary electromagnetic photons. The hidden photon field causes a slight phase shift in the observable interference pattern. It is then shown how the limited sensitivity of this experiment can be largely improved. The key observation is that the hidden photon field causes a leakage of the ordinary magnetic field into the supposedly field-free region. The direct measurement of this magnetic field can provide a sensitive experiment with a good discovery potential, particularly below the ˜meV mass range for hidden photons.

  4. Error statistics of hidden Markov model and hidden Boltzmann model results

    PubMed Central

    Newberg, Lee A

    2009-01-01

    Background Hidden Markov models and hidden Boltzmann models are employed in computational biology and a variety of other scientific fields for a variety of analyses of sequential data. Whether the associated algorithms are used to compute an actual probability or, more generally, an odds ratio or some other score, a frequent requirement is that the error statistics of a given score be known. What is the chance that random data would achieve that score or better? What is the chance that a real signal would achieve a given score threshold? Results Here we present a novel general approach to estimating these false positive and true positive rates that is significantly more efficient than are existing general approaches. We validate the technique via an implementation within the HMMER 3.0 package, which scans DNA or protein sequence databases for patterns of interest, using a profile-HMM. Conclusion The new approach is faster than general naïve sampling approaches, and more general than other current approaches. It provides an efficient mechanism by which to estimate error statistics for hidden Markov model and hidden Boltzmann model results. PMID:19589158

  5. Identifying Exotic Hidden-Charm Pentaquarks

    NASA Astrophysics Data System (ADS)

    Chen, Rui; Liu, Xiang; Li, Xue-Qian; Zhu, Shi-Lin

    2015-09-01

    The LHCb Collaboration at the Large Hadron Collider at CERN discovered two pentaquark states Pc(4380 ) and Pc(4450 ). These two hidden-charm states are interpreted as the loosely bound Σc(2455 )D* and Σc*(2520 )D* molecular states in the boson exchange interaction model, which provides an explanation for why the experimental width of Pc(4450 ) is much narrower than that of Pc(4380 ). The discovery of the new resonances Pc(4380 ) and Pc(4450 ), indeed, opens a new page for hadron physics. The partners of Pc(4380 ) and Pc(4450 ) should be pursued in future experiments.

  6. Dual technicolor with hidden local symmetry

    SciTech Connect

    Belitsky, A. V.

    2010-08-15

    We consider a dual description of the technicolor-like gauge theory within the D4/D8-brane configuration with varying confinement and electroweak symmetry breaking scales. Constructing an effective truncated model valid below a certain cutoff, we identify the particle spectrum with Kaluza-Klein modes of the model in a manner consistent with the hidden local symmetry. Integrating out heavy states, we find that the low-energy action receives nontrivial corrections stemming from the mixing between standard model and heavy gauge bosons, which results in reduction of oblique parameters.

  7. A Hidden Markov Model for Urban-Scale Traffic Estimation Using Floating Car Data

    PubMed Central

    Wang, Xiaomeng; Peng, Ling; Chi, Tianhe; Li, Mengzhu; Yao, Xiaojing; Shao, Jing

    2015-01-01

    Urban-scale traffic monitoring plays a vital role in reducing traffic congestion. Owing to its low cost and wide coverage, floating car data (FCD) serves as a novel approach to collecting traffic data. However, sparse probe data represents the vast majority of the data available on arterial roads in most urban environments. In order to overcome the problem of data sparseness, this paper proposes a hidden Markov model (HMM)-based traffic estimation model, in which the traffic condition on a road segment is considered as a hidden state that can be estimated according to the conditions of road segments having similar traffic characteristics. An algorithm based on clustering and pattern mining rather than on adjacency relationships is proposed to find clusters with road segments having similar traffic characteristics. A multi-clustering strategy is adopted to achieve a trade-off between clustering accuracy and coverage. Finally, the proposed model is designed and implemented on the basis of a real-time algorithm. Results of experiments based on real FCD confirm the applicability, accuracy, and efficiency of the model. In addition, the results indicate that the model is practicable for traffic estimation on urban arterials and works well even when more than 70% of the probe data are missing. PMID:26710073

  8. A Hidden Markov Model for Urban-Scale Traffic Estimation Using Floating Car Data.

    PubMed

    Wang, Xiaomeng; Peng, Ling; Chi, Tianhe; Li, Mengzhu; Yao, Xiaojing; Shao, Jing

    2015-01-01

    Urban-scale traffic monitoring plays a vital role in reducing traffic congestion. Owing to its low cost and wide coverage, floating car data (FCD) serves as a novel approach to collecting traffic data. However, sparse probe data represents the vast majority of the data available on arterial roads in most urban environments. In order to overcome the problem of data sparseness, this paper proposes a hidden Markov model (HMM)-based traffic estimation model, in which the traffic condition on a road segment is considered as a hidden state that can be estimated according to the conditions of road segments having similar traffic characteristics. An algorithm based on clustering and pattern mining rather than on adjacency relationships is proposed to find clusters with road segments having similar traffic characteristics. A multi-clustering strategy is adopted to achieve a trade-off between clustering accuracy and coverage. Finally, the proposed model is designed and implemented on the basis of a real-time algorithm. Results of experiments based on real FCD confirm the applicability, accuracy, and efficiency of the model. In addition, the results indicate that the model is practicable for traffic estimation on urban arterials and works well even when more than 70% of the probe data are missing.

  9. Ethical violations in the clinical setting: the hidden curriculum learning experience of Pakistani nurses.

    PubMed

    Jafree, Sara Rizvi; Zakar, Rubeena; Fischer, Florian; Zakar, Muhammad Zakria

    2015-03-19

    The importance of the hidden curriculum is recognised as a practical training ground for the absorption of medical ethics by healthcare professionals. Pakistan's healthcare sector is hampered by the exclusion of ethics from medical and nursing education curricula and the absence of monitoring of ethical violations in the clinical setting. Nurses have significant knowledge of the hidden curriculum taught during clinical practice, due to long working hours in the clinic and front-line interaction with patients and other practitioners. The means of inquiry for this study was qualitative, with 20 interviews and four focus group discussions used to identify nurses' clinical experiences of ethical violations. Content analysis was used to discover sub-categories of ethical violations, as perceived by nurses, within four pre-defined categories of nursing codes of ethics: 1) professional guidelines and integrity, 2) patient informed consent, 3) patient rights, and 4) co-worker coordination for competency, learning and patient safety. Ten sub-categories of ethical violations were found: nursing students being used as adjunct staff, nurses having to face frequent violence in the hospital setting, patient reluctance to receive treatment from nurses, the near-absence of consent taken from patients for most non-surgical medical procedures, the absence of patient consent taking for receiving treatment from student nurses, the practice of patient discrimination on the basis of a patient's socio-demographic status, nurses withdrawing treatment out of fear for their safety, a non-learning culture and, finally, blame-shifting and non-reportage of errors. Immediate and urgent attention is required to reduce ethical violations in the healthcare sector in Pakistan through collaborative efforts by the government, the healthcare sector, and ethics regulatory bodies. Also, changes in socio-cultural values in hospital organisation, public awareness of how to conveniently report ethical

  10. Probing flavor parameters in the scalar sector and new bounds for the fermion sector

    NASA Astrophysics Data System (ADS)

    Gaitán, R.; Montes de Oca, J. H.; Orduz-Ducuara, J. A.

    2017-07-01

    In this paper we study the flavor-changing mediated by the Higgs boson within a Two-Higgs Doublet Model-III context. We explore the parameter space and, considering recent results, find new limits for the model parameters. We also obtain the total Higgs decay width and the branching ratios for different channels taking limits for the t\\to cV and b\\to sγ processes. Considering different constraints, we estimate the branching ratio for h\\to t^* c in the model as well as the bounds for b \\to sγ,h \\to μ\\tau, and h\\to γ Z. Considering the quark top decays to W\\bar{b}, we obtained Br(h \\to Wc\\bar{b})˜10^{-3}.

  11. Hidden Attractors in Dynamical Systems. From Hidden Oscillations in Hilbert-Kolmogorov Aizerman, and Kalman Problems to Hidden Chaotic Attractor in Chua Circuits

    NASA Astrophysics Data System (ADS)

    Leonov, G. A.; Kuznetsov, N. V.

    From a computational point of view, in nonlinear dynamical systems, attractors can be regarded as self-excited and hidden attractors. Self-excited attractors can be localized numerically by a standard computational procedure, in which after a transient process a trajectory, starting from a point of unstable manifold in a neighborhood of equilibrium, reaches a state of oscillation, therefore one can easily identify it. In contrast, for a hidden attractor, a basin of attraction does not intersect with small neighborhoods of equilibria. While classical attractors are self-excited, attractors can therefore be obtained numerically by the standard computational procedure. For localization of hidden attractors it is necessary to develop special procedures, since there are no similar transient processes leading to such attractors. At first, the problem of investigating hidden oscillations arose in the second part of Hilbert's 16th problem (1900). The first nontrivial results were obtained in Bautin's works, which were devoted to constructing nested limit cycles in quadratic systems, that showed the necessity of studying hidden oscillations for solving this problem. Later, the problem of analyzing hidden oscillations arose from engineering problems in automatic control. In the 50-60s of the last century, the investigations of widely known Markus-Yamabe's, Aizerman's, and Kalman's conjectures on absolute stability have led to the finding of hidden oscillations in automatic control systems with a unique stable stationary point. In 1961, Gubar revealed a gap in Kapranov's work on phase locked-loops (PLL) and showed the possibility of the existence of hidden oscillations in PLL. At the end of the last century, the difficulties in analyzing hidden oscillations arose in simulations of drilling systems and aircraft's control systems (anti-windup) which caused crashes. Further investigations on hidden oscillations were greatly encouraged by the present authors' discovery, in 2010

  12. Women's hidden transcripts about abortion in Brazil.

    PubMed

    Nations, M K; Misago, C; Fonseca, W; Correia, L L; Campbell, O M

    1997-06-01

    Two folk medical conditions, "delayed" (atrasada) and "suspended" (suspendida) menstruation, are described as perceived by poor Brazilian women in Northeast Brazil. Culturally prescribed methods to "regulate" these conditions and provoke menstrual bleeding are also described, including ingesting herbal remedies, patent drugs, and modern pharmaceuticals. The ingestion of such self-administered remedies is facilitated by the cognitive ambiguity, euphemisms, folklore, etc., which surround conception and gestation. The authors argue that the ethnomedical conditions of "delayed" and "suspended" menstruation and subsequent menstrual regulation are part of the "hidden reproductive transcript" of poor and powerless Brazilian women. Through popular culture, they voice their collective dissent to the official, public opinion about the illegality and immorality of induced abortion and the chronic lack of family planning services in Northeast Brazil. While many health professionals consider women's explanations of menstrual regulation as a "cover-up" for self-induced abortions, such popular justifications may represent either an unconscious or artful manipulation of hegemonic, anti-abortion ideology expressed in prudent, unobtrusive and veiled ways. The development of safer abortion alternatives should consider women's hidden reproductive transcripts.

  13. Bayesian structural inference for hidden processes.

    PubMed

    Strelioff, Christopher C; Crutchfield, James P

    2014-04-01

    We introduce a Bayesian approach to discovering patterns in structurally complex processes. The proposed method of Bayesian structural inference (BSI) relies on a set of candidate unifilar hidden Markov model (uHMM) topologies for inference of process structure from a data series. We employ a recently developed exact enumeration of topological ε-machines. (A sequel then removes the topological restriction.) This subset of the uHMM topologies has the added benefit that inferred models are guaranteed to be ε-machines, irrespective of estimated transition probabilities. Properties of ε-machines and uHMMs allow for the derivation of analytic expressions for estimating transition probabilities, inferring start states, and comparing the posterior probability of candidate model topologies, despite process internal structure being only indirectly present in data. We demonstrate BSI's effectiveness in estimating a process's randomness, as reflected by the Shannon entropy rate, and its structure, as quantified by the statistical complexity. We also compare using the posterior distribution over candidate models and the single, maximum a posteriori model for point estimation and show that the former more accurately reflects uncertainty in estimated values. We apply BSI to in-class examples of finite- and infinite-order Markov processes, as well to an out-of-class, infinite-state hidden process.

  14. Monitoring volcano activity through Hidden Markov Model

    NASA Astrophysics Data System (ADS)

    Cassisi, C.; Montalto, P.; Prestifilippo, M.; Aliotta, M.; Cannata, A.; Patanè, D.

    2013-12-01

    During 2011-2013, Mt. Etna was mainly characterized by cyclic occurrences of lava fountains, totaling to 38 episodes. During this time interval Etna volcano's states (QUIET, PRE-FOUNTAIN, FOUNTAIN, POST-FOUNTAIN), whose automatic recognition is very useful for monitoring purposes, turned out to be strongly related to the trend of RMS (Root Mean Square) of the seismic signal recorded by stations close to the summit area. Since RMS time series behavior is considered to be stochastic, we can try to model the system generating its values, assuming to be a Markov process, by using Hidden Markov models (HMMs). HMMs are a powerful tool in modeling any time-varying series. HMMs analysis seeks to recover the sequence of hidden states from the observed emissions. In our framework, observed emissions are characters generated by the SAX (Symbolic Aggregate approXimation) technique, which maps RMS time series values with discrete literal emissions. The experiments show how it is possible to guess volcano states by means of HMMs and SAX.

  15. ESO's Hidden Treasures Brought to Light

    NASA Astrophysics Data System (ADS)

    2011-01-01

    ESO's Hidden Treasures 2010 astrophotography competition attracted nearly 100 entries, and ESO is delighted to announce the winners. Hidden Treasures gave amateur astronomers the opportunity to search ESO's vast archives of astronomical data for a well-hidden cosmic gem. Astronomy enthusiast Igor Chekalin from Russia won the first prize in this difficult but rewarding challenge - the trip of a lifetime to ESO's Very Large Telescope at Paranal, Chile. The pictures of the Universe that can be seen in ESO's releases are impressive. However, many hours of skilful work are required to assemble the raw greyscale data captured by the telescopes into these colourful images, correcting them for distortions and unwanted signatures of the instrument, and enhancing them so as to bring out the details contained in the astronomical data. ESO has a team of professional image processors, but for the ESO's Hidden Treasures 2010 competition, the experts decided to give astronomy and photography enthusiasts the opportunity to show the world what they could do with the mammoth amount of data contained in ESO's archives. The enthusiasts who responded to the call submitted nearly 100 entries in total - far exceeding initial expectations, given the difficult nature of the challenge. "We were completely taken aback both by the quantity and the quality of the images that were submitted. This was not a challenge for the faint-hearted, requiring both an advanced knowledge of data processing and an artistic eye. We are thrilled to have discovered so many talented people," said Lars Lindberg Christensen, Head of ESO's education and Public Outreach Department. Digging through many terabytes of professional astronomical data, the entrants had to identify a series of greyscale images of a celestial object that would reveal the hidden beauty of our Universe. The chance of a great reward for the lucky winner was enough to spur on the competitors; the first prize being a trip to ESO's Very Large

  16. Combating hidden hunger: the role of international agencies.

    PubMed

    Dalmiya, Nita; Schultink, Werner

    2003-12-01

    The importance of micronutrient deficiencies or "hidden hunger" was clearly emphasized by the inclusion of specific goals on iron, vitamin A, and iodine deficiency at the 1990 World Summit for Children and other major international nutrition conferences. Significant progress has since been made toward eliminating vitamin A and iodine deficiencies, with less progress made toward reducing the burden of iron-deficiency anemia. The role of international agencies, such as the World Health Organization, United Nations Children's Fund, Food and Agricultural Organization, and World Bank in assisting countries to make progress toward the World Summit for Children goals has been very important. International agencies have played a critical role in advocating for and raising awareness of these issues at the international, regional, and national levels among policymakers and the general population. Using a rights-based approach, UNICEF and other agencies have been instrumental in elevating to the highest political level the discussion of every child's right to adequate nutrition. International agencies have also been very supportive at the national level in providing technical guidance for programs, including monitoring and evaluation. These agencies have played a critical role in engaging the cooperation of other partners, including bilateral donors, non-governmental organizations, and the private sector for micronutrient programs. Furthermore, international agencies provide financial and material support for micronutrient programs. In the future, such agencies must continue to be heavily involved in programs to achieve the newly confirmed goals for 2010. The present paper focuses on the role of international agencies in combating micronutrient deficiencies, drawing on the lessons learned over the last decade. The first section of the paper summarizes the progress achieved since 1990, and the second section describes the specific role of international agencies in contributing

  17. Skyrmions with vector mesons in the hidden local symmetry approach

    NASA Astrophysics Data System (ADS)

    Ma, Yong-Liang; Yang, Ghil-Seok; Oh, Yongseok; Harada, Masayasu

    2013-02-01

    The roles of light ρ and ω vector mesons in the Skyrmion are investigated in a chiral Lagrangian derived from the hidden local symmetry (HLS) up to O(p4) including the homogeneous Wess-Zumino terms. We write a general “master formula” that allows us to determine the parameters of the HLS Lagrangian from a class of holographic QCD models valid at the large-Nc and -λ (’t Hooft constant) limit by integrating out the infinite towers of vector and axial-vector mesons other than the lowest ρ and ω mesons. Within this approach we find that the physical properties of the Skyrmion as the solitonic description of baryons are independent of the HLS parameter a. Therefore the only parameters of the model are the pion decay constant and the vector-meson mass. Once determined in the meson sector, we have a totally parameter-free theory that allows us to study unequivocally the role of light vector mesons in the Skyrmion structure. We find, as suggested by Sutcliffe, that the inclusion of the ρ meson reduces the soliton mass, which makes the Skyrmion come closer to the Bogomol’nyi-Prasad-Sommerfield soliton, but the role of the ω meson is found to increase the soliton mass. In stark contrast, the Δ-N mass difference, which is determined by the moment of inertia in the adiabatic collective quantization of the Skyrmion, is increased by the ρ vector meson, while it is reduced by the inclusion of the ω meson. All these observations show the importance of the ω meson in the properties of the nucleon and nuclear matter in the Skyrme model.

  18. Seuss's Butter Battle Book: Is There Hidden Harm?

    ERIC Educational Resources Information Center

    Van Cleaf, David W.; Martin, Rita J.

    1986-01-01

    Examines whether elementary school children relate to the "harmful hidden message" about nuclear war in Dr. Seuss's THE BUTTER BATTLE BOOK. After ascertaining the children's cognitive level, they participated in activities to find hidden meanings in stories, including Seuss's book. Students failed to identify the nuclear war message in…

  19. Hidden attractor in the Rabinovich system, Chua circuits and PLL

    NASA Astrophysics Data System (ADS)

    Kuznetsov, N. V.; Leonov, G. A.; Mokaev, T. N.; Seledzhi, S. M.

    2016-06-01

    In this report the existence of hidden attractors in Rabinovich system, phase-locked loop and coupled Chua circuits is considered. It is shown that the existence of hidden attractors may complicate the analysis of the systems and significantly affect the synchronization.

  20. Are Perpetual Points Sufficient for Locating Hidden Attractors?

    NASA Astrophysics Data System (ADS)

    Nazarimehr, Fahimeh; Saedi, Batool; Jafari, Sajad; Sprott, J. C.

    Perpetual Points (PPs) have been introduced as an interesting new topic in nonlinear dynamics, and there is a conjecture that these points can be used to find hidden attractors. This note demonstrates some examples where PPs cannot locate their hidden attractors.

  1. The Hidden Curriculum of Youth Policy: A Dutch Example

    ERIC Educational Resources Information Center

    Hopman, Marit; de Winter, Micha; Koops, Willem

    2014-01-01

    Youth policy is more than a mere response to the actual behavior of children, but it is equally influenced by values and beliefs of policy makers. These values are however rarely made explicit and, therefore, the authors refer to them as "the hidden curriculum" of youth policy. The study investigation explicates this hidden curriculum by…

  2. Seuss's Butter Battle Book: Is There Hidden Harm?

    ERIC Educational Resources Information Center

    Van Cleaf, David W.; Martin, Rita J.

    1986-01-01

    Examines whether elementary school children relate to the "harmful hidden message" about nuclear war in Dr. Seuss's THE BUTTER BATTLE BOOK. After ascertaining the children's cognitive level, they participated in activities to find hidden meanings in stories, including Seuss's book. Students failed to identify the nuclear war message in…

  3. Hidden Curriculum as One of Current Issue of Curriculum

    ERIC Educational Resources Information Center

    Alsubaie, Merfat Ayesh

    2015-01-01

    There are several issues in the education system, especially in the curriculum field that affect education. Hidden curriculum is one of current controversial curriculum issues. Many hidden curricular issues are the result of assumptions and expectations that are not formally communicated, established, or conveyed within the learning environment.…

  4. Secret Codes: The Hidden Curriculum of Semantic Web Technologies

    ERIC Educational Resources Information Center

    Edwards, Richard; Carmichael, Patrick

    2012-01-01

    There is a long tradition in education of examination of the hidden curriculum, those elements which are implicit or tacit to the formal goals of education. This article draws upon that tradition to open up for investigation the hidden curriculum and assumptions about students and knowledge that are embedded in the coding undertaken to facilitate…

  5. Secret Codes: The Hidden Curriculum of Semantic Web Technologies

    ERIC Educational Resources Information Center

    Edwards, Richard; Carmichael, Patrick

    2012-01-01

    There is a long tradition in education of examination of the hidden curriculum, those elements which are implicit or tacit to the formal goals of education. This article draws upon that tradition to open up for investigation the hidden curriculum and assumptions about students and knowledge that are embedded in the coding undertaken to facilitate…

  6. Improving health sector travel.

    PubMed

    Hurdle, David; Davis, Adrian

    2004-10-01

    Preventing ill health and obesity and building more physical activity into our daily lives have never been so high on the agenda, and the way we travel can help. Many workplaces and schools are drawing up travel plans, with the aims usually to minimise car use and encourage healthier and more environmentally friendly travel. The Transport White Paper of 1998 advocated travel plans and singled out hospitals for action. Travel plans continue to be a focus within the latest Transport White Paper, launched in July 2004. This article covers various prompts to the health sector to implement travel plans. It addresses issues and concerns facing NHS Trusts, the practical things Trusts can do, and the increasing amount of good practice available. Finally, it demonstrates that travel plans can work, and are working, in the health sector.

  7. Integrated Radial Probe Transition From MMIC to Waveguide

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Chattopadhyay, Goutam

    2007-01-01

    A radial probe transition between a monolithic microwave integrated circuit (MMIC) and a waveguide has been designed for operation at frequency of 340 GHz and to be fabricated as part of a monolithic unit that includes the MMIC. Integrated radial probe transitions like this one are expected to be essential components of future MMIC amplifiers operating at frequencies above 200 GHz. While MMIC amplifiers for this frequency range have not yet been widely used because they have only recently been developed, there are numerous potential applications for them-- especially in scientific instruments, test equipment, radar, and millimeter-wave imaging systems for detecting hidden weapons.

  8. Sector Study Guideline

    DTIC Science & Technology

    1990-03-01

    LIMITS . . . . . . . . 8 5.1 Market Groups . ................ 8 5.2 Market Group A and the Level of Effort (LOE) Assessment...9 5.3 Market Groups B and Level of Effort (LOE) Assessment . . . . . . . . . 10 5.4 Market Group C and the Level of Effort Assessment 11 5.5... Market Groups Al, B1, C1 versus A2, B2, C2 (LOE) 11 6.0 AVAILABILITY OF INFORMATION . . . . . . . . . . . . . 12 7.0 OVERVIEW OF THE PROPOSED SECTOR

  9. Identifying hidden sexual bridging communities in Chicago.

    PubMed

    Youm, Yoosik; Mackesy-Amiti, Mary Ellen; Williams, Chyvette T; Ouellet, Lawrence J

    2009-07-01

    Bridge populations can play a central role in the spread of human immunodeficiency virus (HIV) by providing transmission links between higher and lower prevalence populations. While social network methods are well suited to the study of bridge populations, analyses tend to focus on dyads (i.e., risk between drug and/or sex partners) and ignore bridges between distinct subpopulations. This study takes initial steps toward moving the analysis of sexual network linkages beyond individual and risk group levels to a community level in which Chicago's 77 community areas are examined as subpopulations for the purpose of identifying potential bridging communities. Of particular interest are "hidden" bridging communities; that is, areas with above-average levels of sexual ties with other areas but whose below-average AIDS prevalence may hide their potential importance for HIV prevention. Data for this analysis came from the first wave of recruiting at the Chicago Sexual Acquisition and Transmission of HIV Cooperative Agreement Program site. Between August 2005 through October 2006, respondent-driven sampling was used to recruit users of heroin, cocaine, or methamphetamine, men who have sex with men regardless of drug use, the sex partners of these two groups, and sex partners of the sex partners. In this cross-sectional study of the sexual transmission of HIV, participants completed a network-focused computer-assisted self-administered interview, which included questions about the geographic locations of sexual contacts with up to six recent partners. Bridging scores for each area were determined using a matrix representing Chicago's 77 community areas and were assessed using two measures: non-redundant ties and flow betweenness. Bridging measures and acquired immunodeficiency syndrome (AIDS) case prevalence rates were plotted for each community area on charts representing four conditions: below-average bridging and AIDS prevalence, below-average bridging and above

  10. Reconstructing the dark sector interaction with LISA

    NASA Astrophysics Data System (ADS)

    Cai, Rong-Gen; Tamanini, Nicola; Yang, Tao

    2017-05-01

    We perform a forecast analysis of the ability of the LISA space-based interferometer to reconstruct the dark sector interaction using gravitational wave standard sirens at high redshift. We employ Gaussian process methods to reconstruct the distance-redshift relation in a model independent way. We adopt simulated catalogues of standard sirens given by merging massive black hole binaries visible by LISA, with an electromagnetic counterpart detectable by future telescopes. The catalogues are based on three different astrophysical scenarios for the evolution of massive black hole mergers based on the semi-analytic model of E. Barausse, Mon. Not. Roy. Astron. Soc. 423 (2012) 2533. We first use these standard siren datasets to assess the potential of LISA in reconstructing a possible interaction between vacuum dark energy and dark matter. Then we combine the LISA cosmological data with supernovae data simulated for the Dark Energy Survey. We consider two scenarios distinguished by the time duration of the LISA mission: 5 and 10 years. Using only LISA standard siren data, the dark sector interaction can be well reconstructed from redshift z~1 to z~3 (for a 5 years mission) and z~1 up to z~5 (for a 10 years mission), though the reconstruction is inefficient at lower redshift. When combined with the DES datasets, the interaction is well reconstructed in the whole redshift region from 0z~ to z~3 (5 yr) and z~0 to z~5 (10 yr), respectively. Massive black hole binary standard sirens can thus be used to constrain the dark sector interaction at redshift ranges not reachable by usual supernovae datasets which probe only the zlesssim 1.5 range. Gravitational wave standard sirens will not only constitute a complementary and alternative way, with respect to familiar electromagnetic observations, to probe the cosmic expansion, but will also provide new tests to constrain possible deviations from the standard ΛCDM dynamics, especially at high redshift.

  11. Exciton dynamics reveal aggregates with intermolecular order at hidden interfaces in solution-cast organic semiconducting films.

    PubMed

    Wong, Cathy Y; Cotts, Benjamin L; Wu, Hao; Ginsberg, Naomi S

    2015-01-12

    Large-scale organic electronics manufacturing requires solution processing. For small-molecule organic semiconductors, solution processing results in crystalline domains with high charge mobility, but the interfaces between these domains impede charge transport, degrading device performance. Although understanding these interfaces is essential to improve device performance, their intermolecular and electronic structure is unknown: they are smaller than the diffraction limit, are hidden from surface probe techniques, and their nanoscale heterogeneity is not typically resolved using X-ray methods. Here we use transient absorption microscopy to isolate a unique signature of a hidden interface in a TIPS-pentacene thin film, exposing its exciton dynamics and intermolecular structure. Surprisingly, instead of finding an abrupt grain boundary, we reveal that the interface can be composed of nanoscale crystallites interleaved by a web of interfaces that compound decreases in charge mobility. Our novel approach provides critical missing information on interface morphology necessary to correlate solution-processing methods to optimal device performance.

  12. Exciton dynamics reveal aggregates with intermolecular order at hidden interfaces in solution-cast organic semiconducting films

    NASA Astrophysics Data System (ADS)

    Wong, Cathy Y.; Cotts, Benjamin L.; Wu, Hao; Ginsberg, Naomi S.

    2015-01-01

    Large-scale organic electronics manufacturing requires solution processing. For small-molecule organic semiconductors, solution processing results in crystalline domains with high charge mobility, but the interfaces between these domains impede charge transport, degrading device performance. Although understanding these interfaces is essential to improve device performance, their intermolecular and electronic structure is unknown: they are smaller than the diffraction limit, are hidden from surface probe techniques, and their nanoscale heterogeneity is not typically resolved using X-ray methods. Here we use transient absorption microscopy to isolate a unique signature of a hidden interface in a TIPS-pentacene thin film, exposing its exciton dynamics and intermolecular structure. Surprisingly, instead of finding an abrupt grain boundary, we reveal that the interface can be composed of nanoscale crystallites interleaved by a web of interfaces that compound decreases in charge mobility. Our novel approach provides critical missing information on interface morphology necessary to correlate solution-processing methods to optimal device performance.

  13. Carelessness: A Hidden Doxa of Higher Education

    ERIC Educational Resources Information Center

    Lynch, Kathleen

    2010-01-01

    This article explores the implications of new public sector "reforms" for the culture of higher education. It argues that a culture of carelessness, grounded in Cartesian rationalism, has been exacerbated by new managerialism. The article challenges a prevailing sociological assumption that the character of higher education culture is primarily…

  14. Carelessness: A Hidden Doxa of Higher Education

    ERIC Educational Resources Information Center

    Lynch, Kathleen

    2010-01-01

    This article explores the implications of new public sector "reforms" for the culture of higher education. It argues that a culture of carelessness, grounded in Cartesian rationalism, has been exacerbated by new managerialism. The article challenges a prevailing sociological assumption that the character of higher education culture is primarily…

  15. The hidden biology of sponges and ctenophores.

    PubMed

    Dunn, Casey W; Leys, Sally P; Haddock, Steven H D

    2015-05-01

    Animal evolution is often presented as a march toward complexity, with different living animal groups each representing grades of organization that arose through the progressive acquisition of complex traits. There are now many reasons to reject this classical hypothesis. Not only is it incompatible with recent phylogenetic analyses, but it is also an artifact of 'hidden biology', that is, blind spots to complex traits in non-model species. A new hypothesis of animal evolution, where many complex traits have been repeatedly gained and lost, is emerging. As we discuss here, key details of this new model hinge on a better understanding of the Porifera and Ctenophora, which have each been hypothesized to be sister to all other animals, but are poorly studied and often misrepresented.

  16. Identifying Exotic Hidden-Charm Pentaquarks.

    PubMed

    Chen, Rui; Liu, Xiang; Li, Xue-Qian; Zhu, Shi-Lin

    2015-09-25

    The LHCb Collaboration at the Large Hadron Collider at CERN discovered two pentaquark states P_{c}(4380) and P_{c}(4450). These two hidden-charm states are interpreted as the loosely bound Σ_{c}(2455)D^{*} and Σ_{c}^{*}(2520)D^{*} molecular states in the boson exchange interaction model, which provides an explanation for why the experimental width of P_{c}(4450) is much narrower than that of P_{c}(4380). The discovery of the new resonances P_{c}(4380) and P_{c}(4450), indeed, opens a new page for hadron physics. The partners of P_{c}(4380) and P_{c}(4450) should be pursued in future experiments.

  17. Secrets of Hidden Valley on Mars

    NASA Image and Video Library

    2015-10-08

    An image taken at the Hidden Valley site, en-route to Mount Sharp, by NASA Curiosity rover. A variety of mudstone strata in the area indicate a lakebed deposit, with river- and stream-related deposits nearby. Decoding the history of how these sedimentary rocks were formed, and during what period of time, was a key component in the confirming of the role of water and sedimentation in the formation of the floor of Gale Crater and Mount Sharp. This image was taken by the Mast Camera (Mastcam) on Curiosity on the 703rd Martian day, or sol, of the mission. Malin Space Science Systems, San Diego, built and operates Curiosity's Mastcam. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, built the rover and manages the project for NASA's Science Mission Directorate, Washington. http://photojournal.jpl.nasa.gov/catalog/PIA19840

  18. Uncovering hidden flows in physical networks

    NASA Astrophysics Data System (ADS)

    Wang, Chengwei; Grebogi, Celso; Baptista, Murilo S.

    2017-06-01

    Understanding the interactions among nodes in a complex network is of great importance, since they disclose how these nodes are cooperatively supporting the functioning of the network. Scientists have developed numerous methods to uncover the underlying adjacent physical connectivity based on measurements of functional quantities of the nodes states. Often, the physical connectivity, the adjacency matrix, is available. Yet, little is known about how this adjacent connectivity impacts on the “hidden” flows being exchanged between any two arbitrary nodes, after travelling longer non-adjacent paths. In this letter, we show that hidden physical flows in conservative flow networks, a quantity that is usually inaccessible to measurements, can be determined by the interchange of physical flows between any pair of adjacent nodes. Our approach applies to steady or dynamic state of either linear or non-linear complex networks that can be modelled by conservative flow networks, such as gas supply networks, water supply networks and power grids.

  19. Aluminium Diphosphamethanides: Hidden Frustrated Lewis Pairs.

    PubMed

    Styra, Steffen; Radius, Michael; Moos, Eric; Bihlmeier, Angela; Breher, Frank

    2016-07-04

    The synthesis and characterisation of two aluminium diphosphamethanide complexes, [Al(tBu)2 {κ(2) P,P'-Mes*PCHPMes*}] (3) and [Al(C6 F5 )2 {κ(2) P,P'-Mes*PCHPMes*}] (4), and the silylated analogue, Mes*PCHP(SiMe3 )Mes* (5), are reported. The aluminium complexes feature four-membered PCPAl core structures consisting of diphosphaallyl ligands. The silylated phosphine 5 was found to be a valuable precursor for the synthesis of 4 as it cleanly reacts with the diaryl aluminium chloride [(C6 F5 )2 AlCl]2 . The aluminium complex 3 reacts with molecular dihydrogen at room temperature under formation of the acyclic σ(2) λ(3) ,σ(3) λ(3) -diphosphine Mes*PCHP(H)Mes* and the corresponding dialkyl aluminium hydride [tBu2 AlH]3 . Thus, 3 belongs to the family of so-called hidden frustrated Lewis pairs.

  20. Hidden baryons: The physics of Compton composites

    NASA Astrophysics Data System (ADS)

    Mayer, Frederick J.

    2016-06-01

    A large fraction of the mass-energy of the Universe appears to be composed of Compton composites. How is it then that these composites are not frequently observed in experiments? This paper addresses this question, and others, by reviewing recent publications that: 1) introduced Compton composites, 2) showed how and where they are formed and 3) explained how they interact with other systems. Though ubiquitous in many physical situations, Compton composites are almost completely hidden in experiments due to their unique interaction characteristics. Still, their presence has been indirectly observed, though not interpreted as such until recently. Looking to the future, direct-detection experiments are proposed that could verify the composites' components. It is with deep sadness that I dedicate this paper to my mentor, collaborator, and friend, Dr. John R. Reitz, who passed away within days of the publication of our paper “Compton Composites Late in the Early Universe”.

  1. Probabilistic Resilience in Hidden Markov Models

    NASA Astrophysics Data System (ADS)

    Panerati, Jacopo; Beltrame, Giovanni; Schwind, Nicolas; Zeltner, Stefan; Inoue, Katsumi

    2016-05-01

    Originally defined in the context of ecological systems and environmental sciences, resilience has grown to be a property of major interest for the design and analysis of many other complex systems: resilient networks and robotics systems other the desirable capability of absorbing disruption and transforming in response to external shocks, while still providing the services they were designed for. Starting from an existing formalization of resilience for constraint-based systems, we develop a probabilistic framework based on hidden Markov models. In doing so, we introduce two new important features: stochastic evolution and partial observability. Using our framework, we formalize a methodology for the evaluation of probabilities associated with generic properties, we describe an efficient algorithm for the computation of its essential inference step, and show that its complexity is comparable to other state-of-the-art inference algorithms.

  2. Magneto-Radar Hidden Metal Detector

    DOEpatents

    McEwan, Thomas E.

    2005-07-05

    A varying magnetic field excites slight vibrations in an object and a radar sensor detects the vibrations at a harmonic of the excitation frequency. The synergy of the magnetic excitation and radar detection provides increased detection range compared to conventional magnetic metal detectors. The radar rejects background clutter by responding only to reflecting objects that are vibrating at a harmonic excitation field, thereby significantly improving detection reliability. As an exemplary arrangement, an ultra-wideband micropower impulse radar (MIR) is capable of being employed to provide superior materials penetration while providing range information. The magneto-radar may be applied to pre-screening magnetic resonance imaging (MRI) patients, landmine detection and finding hidden treasures.

  3. Hidden fungi, emergent properties: endophytes and microbiomes.

    PubMed

    Porras-Alfaro, Andrea; Bayman, Paul

    2011-01-01

    Endophytes are microorganisms that live within plant tissues without causing symptoms of disease. They are important components of plant microbiomes. Endophytes interact with, and overlap in function with, other core microbial groups that colonize plant tissues, e.g., mycorrhizal fungi, pathogens, epiphytes, and saprotrophs. Some fungal endophytes affect plant growth and plant responses to pathogens, herbivores, and environmental change; others produce useful or interesting secondary metabolites. Here, we focus on new techniques and approaches that can provide an integrative understanding of the role of fungal endophytes in the plant microbiome. Clavicipitaceous endophytes of grasses are not considered because they have unique properties distinct from other endophytes. Hidden from view and often overlooked, endophytes are emerging as their diversity, importance for plant growth and survival, and interactions with other organisms are revealed. Copyright © 2011 by Annual Reviews. All rights reserved.

  4. Skyrmions with holography and hidden local symmetry

    SciTech Connect

    Nawa, Kanabu; Hosaka, Atsushi; Suganuma, Hideo

    2009-06-15

    We study baryons as Skyrmions in holographic QCD with D4/D8/D8 multi-D brane system in type IIA superstring theory, and also in the nonlinear sigma model with hidden local symmetry. Comparing these two models, we find that the extra dimension and its nontrivial curvature can largely change the role of (axial) vector mesons for baryons in four-dimensional space-time. In the hidden local symmetry approach, the {rho}-meson field as a massive Yang-Mills field has a singular configuration in Skyrmion, which gives a strong repulsion for the baryon as a stabilizer. When the a{sub 1} meson is added in this approach, the stability of Skyrmion is lost by the cancellation of {rho} and a{sub 1} contributions. On the contrary, in holographic QCD, the {rho}-meson field does not appear as a massive Yang-Mills field due to the extra dimension and its nontrivial curvature. We show that the {rho}-meson field has a regular configuration in Skyrmion, which gives a weak attraction for the baryon in holographic QCD. We argue that Skyrmion with {pi}, {rho}, and a{sub 1} mesons become stable due to the curved extra dimension and also the presence of the Skyrme term in holographic QCD. From this result, we also discuss the features of our truncated-resonance analysis on baryon properties with {pi} and {rho} mesons below the cutoff scale M{sub KK}{approx}1 GeV in holographic QCD, which is compared with other 5D instanton analysis.

  5. Hidden-charm pentaquarks and their hidden-bottom and Bc-like partner states

    NASA Astrophysics Data System (ADS)

    Wu, Jing; Liu, Yan-Rui; Chen, Kan; Liu, Xiang; Zhu, Shi-Lin

    2017-02-01

    In the framework of the color-magnetic interaction, we have systematically studied the mass splittings of the possible hidden-charm pentaquarks q q q c c ¯ (q =u , d , s ) where the three light quarks are in a color-octet state. We find that (i) the LHCb Pc states fall in the mass region of the studied system, (ii) most pentaquarks should be broad states since their S -wave open-charm decays are allowed while the lowest state is the JP=1/2- Λ -like pentaquark with probably the suppressed ηcΛ decay mode only, and (iii) the JP=5/2- states do not decay through the S wave and their widths are not so broad. The masses and widths of the two LHCb Pc baryons are compatible with such pentaquark states. We also explore the hidden-bottom and Bc-like partners of the hidden-charm states and find the possible existence of the pentaquarks which are lower than the relevant hadronic molecules.

  6. The hidden costs of coastal hazards: Implications for risk assessment and mitigation

    USGS Publications Warehouse

    Kunreuther, H.; Platt, R.; Baruch, S.; Bernknopf, R.L.; Buckley, M.; Burkett, V.; Conrad, D.; Davidson, T.; Deutsch, K.; Geis, D.; Jannereth, M.; Knap, A.; Lane, H.; Ljung, G.; McCauley, M.; Mileti, D.; Miller, T.; Morrow, B.; Meyers, J.; Pielke, R.; Pratt, A.; Tripp, J.

    2000-01-01

    Society has limited hazard mitigation dollars to invest. Which actions will be most cost effective, considering the true range of impacts and costs incurred? In 1997, the H. John Heinz III Center for Science, Economics and the Environment began a two-year study with a panel of experts to help develop new strategies to identify and reduce the costs of weather-related hazards associated with rapidly increasing coastal development activities.The Hidden Costs of Coastal Hazards presents the panel's findings, offering the first in-depth study that considers the costs of coastal hazards to natural resources, social institutions, business, and the built environment. Using Hurricane Hugo, which struck South Carolina in 1989, as a case study, it provides for the first time information on the full range of economic costs caused by a major coastal hazard event. The book:describes and examines unreported, undocumented, and hidden costs such as losses due to business interruption, reduction in property values, interruption of social services, psychological trauma, damage to natural systems, and othersexamines the concepts of risk and vulnerability, and discusses conventional approaches to risk assessment and the emerging area of vulnerability assessmentrecommends a comprehensive framework for developing and implementing mitigation strategiesdocuments the human impact of Hurricane Hugo and provides insight from those who lived through it.The Hidden Costs of Coastal Hazards takes a structured approach to the problem of coastal hazards, offering a new framework for community-based hazard mitigation along with specific recommendations for implementation. Decisionmakers -- both policymakers and planners -- who are interested in coastal hazard issues will find the book a unique source of new information and insight, as will private-sector decisionmakers including lenders, investors, developers, and insurers of coastal property.

  7. Various types of holographic metal/superconductor phase transitions with dark matter sector

    NASA Astrophysics Data System (ADS)

    Peng, Yan; Chen, Tao; Liu, Guohua; Ma, Pengwei

    We generalize the holographic superconductor model with dark matter sector by including the Stückelberg mechanism in the four-dimensional anti-de Sitter (AdS) black hole background away from the probe limit. We study effects of the dark matter sector on the s-wave scalar condensation and find that the dark matter sector affects the critical phase transition temperature and also the order of phase transitions. At last, we conclude that the dark matter sector brings richer physics in this general metal/superconductor system.

  8. Radio for hidden-photon dark matter detection

    DOE PAGES

    Chaudhuri, Saptarshi; Graham, Peter W.; Irwin, Kent; ...

    2015-10-08

    We propose a resonant electromagnetic detector to search for hidden-photon dark matter over an extensive range of masses. Hidden-photon dark matter can be described as a weakly coupled “hidden electric field,” oscillating at a frequency fixed by the mass, and able to penetrate any shielding. At low frequencies (compared to the inverse size of the shielding), we find that the observable effect of the hidden photon inside any shielding is a real, oscillating magnetic field. We outline experimental setups designed to search for hidden-photon dark matter, using a tunable, resonant LC circuit designed to couple to this magnetic field. Ourmore » “straw man” setups take into consideration resonator design, readout architecture and noise estimates. At high frequencies, there is an upper limit to the useful size of a single resonator set by 1/ν. However, many resonators may be multiplexed within a hidden-photon coherence length to increase the sensitivity in this regime. Hidden-photon dark matter has an enormous range of possible frequencies, but current experiments search only over a few narrow pieces of that range. As a result, we find the potential sensitivity of our proposal is many orders of magnitude beyond current limits over an extensive range of frequencies, from 100 Hz up to 700 GHz and potentially higher.« less

  9. Radio for hidden-photon dark matter detection

    SciTech Connect

    Chaudhuri, Saptarshi; Graham, Peter W.; Irwin, Kent; Mardon, Jeremy; Rajendran, Surjeet; Zhao, Yue

    2015-10-08

    We propose a resonant electromagnetic detector to search for hidden-photon dark matter over an extensive range of masses. Hidden-photon dark matter can be described as a weakly coupled “hidden electric field,” oscillating at a frequency fixed by the mass, and able to penetrate any shielding. At low frequencies (compared to the inverse size of the shielding), we find that the observable effect of the hidden photon inside any shielding is a real, oscillating magnetic field. We outline experimental setups designed to search for hidden-photon dark matter, using a tunable, resonant LC circuit designed to couple to this magnetic field. Our “straw man” setups take into consideration resonator design, readout architecture and noise estimates. At high frequencies, there is an upper limit to the useful size of a single resonator set by 1/ν. However, many resonators may be multiplexed within a hidden-photon coherence length to increase the sensitivity in this regime. Hidden-photon dark matter has an enormous range of possible frequencies, but current experiments search only over a few narrow pieces of that range. As a result, we find the potential sensitivity of our proposal is many orders of magnitude beyond current limits over an extensive range of frequencies, from 100 Hz up to 700 GHz and potentially higher.

  10. Hidden Bifurcations and Attractors in Nonsmooth Dynamical Systems

    NASA Astrophysics Data System (ADS)

    Jeffrey, Mike R.

    We investigate the role of hidden terms at switching surfaces in piecewise smooth vector fields. Hidden terms are zero everywhere except at the switching surfaces, but appear when blowing up the switching surface into a switching layer. When discontinuous systems do surprising things, we can often make sense of them by extending our intuition for smooth system to the switching layer. We illustrate the principle here with a few attractors that are hidden inside the switching layer, being evident in the flow, despite not being directly evident in the vector field outside the switching surface. These can occur either at a single switch (where we will introduce hidden terms somewhat artificially to demonstrate the principle), or at the intersection of multiple switches (where hidden terms arise inescapably). A more subtle role of hidden terms is in bifurcations, and we revisit some simple cases from previous literature here, showing that they exhibit degeneracies inside the switching layer, and that the degeneracies can be broken using hidden terms. We illustrate the principle in systems with one or two switches.

  11. Suppressing the QCD axion abundance by hidden monopoles

    NASA Astrophysics Data System (ADS)

    Kawasaki, Masahiro; Takahashi, Fuminobu; Yamada, Masaki

    2016-02-01

    We study the Witten effect of hidden monopoles on the QCD axion dynamics, and show that its abundance as well as isocurvature perturbations can be significantly suppressed if there is a sufficient amount of hidden monopoles. When the hidden monopoles make up a significant fraction of dark matter, the Witten effect suppresses the abundance of axion with the decay constant smaller than 1012GeV. The cosmological domain wall problem of the QCD axion can also be avoided, relaxing the upper bound on the decay constant when the Peccei-Quinn symmetry is spontaneously broken after inflation.

  12. Hidden Area and Mechanical Nonlinearities in Freestanding Graphene

    NASA Astrophysics Data System (ADS)

    Nicholl, Ryan J. T.; Lavrik, Nickolay V.; Vlassiouk, Ivan; Srijanto, Bernadeta R.; Bolotin, Kirill I.

    2017-06-01

    We investigated the effect of out-of-plane crumpling on the mechanical response of graphene membranes. In our experiments, stress was applied to graphene membranes using pressurized gas while the strain state was monitored through two complementary techniques: interferometric profilometry and Raman spectroscopy. By comparing the data obtained through these two techniques, we determined the geometric hidden area which quantifies the crumpling strength. While the devices with hidden area ˜0 % obeyed linear mechanics with biaxial stiffness 428 ±10 N /m , specimens with hidden area in the range 0.5%-1.0% were found to obey an anomalous nonlinear Hooke's law with an exponent ˜0.1 .

  13. End of life and beyond as hidden curriculum.

    PubMed

    Condon, Barbara Backer; Grimsley, Catherine; Kelley, Teresa; Nissen, Mary Kay

    2014-01-01

    End-of-life experiences are unique. Most can vividly recall feelings during those times. Governing boards in the United States attempt to guide nursing faculty regarding end of life curriculum. Yet, the beliefs of faculty members arising from those unique experiences can alter the tone and message of what students are actually taught--often surfacing as hidden curriculum. In this column the authors discuss hidden curriculum while presenting the beliefs regarding end of life, of four nursing faculty members from a single university. Heightened awareness and respect for the beliefs of all faculty members within any university setting is imperative in decreasing the development of hidden curriculum.

  14. Hidden sources of mercury in clinical laboratories.

    PubMed

    Alvarez-Chavez, C R; Federico-Perez, R A; Gomez-Alvarez, A; Velazquez-Contreras, L E; Perez-Rios, R

    2014-09-01

    The healthcare sector is an important contributor to mercury (Hg) pollution because of the potential presence of mercury in thermometers, blood pressure cuffs, amalgams, etc. There are also other potential sources of mercury in this sector which are used frequently and in high volumes where the presence of the metal is not obvious and which might be collectively contributing to pollution. For instance, some chemicals used for the clinical diagnosis of illness may contain mercury. The goal of this study was to investigate potential sources of mercury pollution, which originate from clinical laboratory discharges, using an exploratory approach. The focus was on the residue generated during automatic analysis of patients' bodily fluids at a medical center in Hermosillo, Sonora, Mexico. This study shows an overview of what might be happening in the region or the country related to non-obvious sources of mercury in the healthcare sector. The results showed measurable levels of mercury in the residues coming from urine sediment analysis. These amounts do not exceed the maximum allowed by Mexican environmental regulations; nevertheless, the frequency and cumulative volume of residues generated, combined with the potential for persistence and the bioaccumulation of mercury in the environment, warrant attention. The work carried out in this study is being taken as a model for future studies for pollution prevention in the healthcare sector with the goal of measuring mercury emissions to the environment from clinical laboratory wastewater, including identifying sources which--while not obvious--could be important given the frequency and volume of their use in the clinical diagnosis.

  15. Traces of the hidden-charm S=-1 pentaquark in the Λb→J/ΨηΛ decay

    NASA Astrophysics Data System (ADS)

    Magas, V. K.; Feijoo, A.; Oset, E.; Ramos, A.

    2017-03-01

    The hidden charm pentaquark state Pc(4450), observed recently by the LHCb collaboration in the Λb→J/ψK- p decay, may be of molecular nature, as advocated by some unitary approaches that also predict pentaquark partners in the strangeness S=-1 sector. In this work we argue that a hidden-charm strange pentaquark could also be seen in the decay of theΛb, but through the J/ψηΛ decay mode, by studying the invariant mass spectrum of J/ψΛ pairs. In our model we assume a standard weak decay topology, then incorporate the hadronization process and final state interaction effects, and we find that the J/ψηΛ final state is populated with the strength similar to that of the J/ψK- p. We have studied the dependence of our results on reasonable changes in the parameters of the models as well as on the unknown properties of the speculated hidden charm strange pentaquark. We have observed that, while there appear changes in the position of the peak and in the shapes of the distributions, a resonance signal in the J/ψΛ invariant mass spectrum is clearly seen in all the cases. This gives us confidence that such an experimental study could result into a successful proof of the existence of this new state.

  16. Probe tip heating assembly

    SciTech Connect

    Schmitz, Roger William; Oh, Yunje

    2016-10-25

    A heating assembly configured for use in mechanical testing at a scale of microns or less. The heating assembly includes a probe tip assembly configured for coupling with a transducer of the mechanical testing system. The probe tip assembly includes a probe tip heater system having a heating element, a probe tip coupled with the probe tip heater system, and a heater socket assembly. The heater socket assembly, in one example, includes a yoke and a heater interface that form a socket within the heater socket assembly. The probe tip heater system, coupled with the probe tip, is slidably received and clamped within the socket.

  17. Hydrodynamic ultrasonic probe

    DOEpatents

    Day, Robert A.; Conti, Armond E.

    1980-01-01

    An improved probe for in-service ultrasonic inspection of long lengths of a workpiece, such as small diameter tubing from the interior. The improved probe utilizes a conventional transducer or transducers configured to inspect the tubing for flaws and/or wall thickness variations. The probe utilizes a hydraulic technique, in place of the conventional mechanical guides or bushings, which allows the probe to move rectilinearly or rotationally while preventing cocking thereof in the tube and provides damping vibration of the probe. The probe thus has lower friction and higher inspection speed than presently known probes.

  18. The sun's magnetic sector structure

    NASA Technical Reports Server (NTRS)

    Svalgaard, L.; Wilcox, J. M.; Scherrer, P. H.; Howard, R.

    1975-01-01

    The synoptic appearance of solar magnetic sectors is studied using 454 sector boundaries observed at earth during 1959-1973. The sectors are clearly visible in the photospheric magnetic field. Sector boundaries can be clearly identified as north-south running demarcation lines between regions of persistent magnetic polarity imbalances. These regions extend up to about 35 deg of latitude on both sides of the equator. They generally do not extend into the polar caps. The polar cap boundary can be identified as an east-west demarcation line marking the poleward limit of the sectors. The typical flux imbalance for a magnetic sector is about 4 x 10 to the 21st power Maxwells.

  19. West side, oblique, partially hidden by trees, utility safety fence, ...

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

    West side, oblique, partially hidden by trees, utility safety fence, and the deep shadow of the 1962 annex. View to northeast. - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  20. Modelling proteins' hidden conformations to predict antibiotic resistance

    NASA Astrophysics Data System (ADS)

    Hart, Kathryn M.; Ho, Chris M. W.; Dutta, Supratik; Gross, Michael L.; Bowman, Gregory R.

    2016-10-01

    TEM β-lactamase confers bacteria with resistance to many antibiotics and rapidly evolves activity against new drugs. However, functional changes are not easily explained by differences in crystal structures. We employ Markov state models to identify hidden conformations and explore their role in determining TEM's specificity. We integrate these models with existing drug-design tools to create a new technique, called Boltzmann docking, which better predicts TEM specificity by accounting for conformational heterogeneity. Using our MSMs, we identify hidden states whose populations correlate with activity against cefotaxime. To experimentally detect our predicted hidden states, we use rapid mass spectrometric footprinting and confirm our models' prediction that increased cefotaxime activity correlates with reduced Ω-loop flexibility. Finally, we design novel variants to stabilize the hidden cefotaximase states, and find their populations predict activity against cefotaxime in vitro and in vivo. Therefore, we expect this framework to have numerous applications in drug and protein design.

  1. Hidden Risks of Erectile Dysfunction "Treatments" Sold Online

    MedlinePlus

    ... Home For Consumers Consumer Updates Hidden Risks of Erectile Dysfunction 'Treatments' Sold Online Share Tweet Linkedin Pin it ... Men looking online for "dietary supplements" to treat erectile dysfunction (ED) or enhance their sexual performance should beware: ...

  2. When memory pays: Discord in hidden Markov models

    NASA Astrophysics Data System (ADS)

    Lathouwers, Emma; Bechhoefer, John

    2017-06-01

    When is keeping a memory of observations worthwhile? We use hidden Markov models to look at phase transitions that emerge when comparing state estimates in systems with discrete states and noisy observations. We infer the underlying state of the hidden Markov models from the observations in two ways: through naive observations, which take into account only the current observation, and through Bayesian filtering, which takes the history of observations into account. Defining a discord order parameter to distinguish between the different state estimates, we explore hidden Markov models with various numbers of states and symbols and varying transition-matrix symmetry. All behave similarly. We calculate analytically the critical point where keeping a memory of observations starts to pay off. A mapping between hidden Markov models and Ising models gives added insight into the associated phase transitions.

  3. A "hidden" co-crystal of caffeine and adipic acid.

    PubMed

    Bucar, Dejan-Kresimir; Henry, Rodger F; Lou, Xiaochun; Borchardt, Thomas B; Zhang, Geoff G Z

    2007-02-07

    Co-crystal formation between caffeine and adipic acid has been explored over the years without success; utilizing the newly developed co-crystal screening method, we have finally discovered this "hidden" caffeine and adipic acid co-crystal.

  4. Modelling proteins’ hidden conformations to predict antibiotic resistance

    PubMed Central

    Hart, Kathryn M.; Ho, Chris M. W.; Dutta, Supratik; Gross, Michael L.; Bowman, Gregory R.

    2016-01-01

    TEM β-lactamase confers bacteria with resistance to many antibiotics and rapidly evolves activity against new drugs. However, functional changes are not easily explained by differences in crystal structures. We employ Markov state models to identify hidden conformations and explore their role in determining TEM’s specificity. We integrate these models with existing drug-design tools to create a new technique, called Boltzmann docking, which better predicts TEM specificity by accounting for conformational heterogeneity. Using our MSMs, we identify hidden states whose populations correlate with activity against cefotaxime. To experimentally detect our predicted hidden states, we use rapid mass spectrometric footprinting and confirm our models’ prediction that increased cefotaxime activity correlates with reduced Ω-loop flexibility. Finally, we design novel variants to stabilize the hidden cefotaximase states, and find their populations predict activity against cefotaxime in vitro and in vivo. Therefore, we expect this framework to have numerous applications in drug and protein design. PMID:27708258

  5. Diagnostic Sampling to Reveal Hidden Lead and Copper Health Risks

    EPA Science Inventory

    Lead, copper and other metallic contamination sources in premise drinking water plumbing systems, are unevenly distributed and are usually hidden from thought, view, or both. Many sampling protocols exist, each with some set of implicit assumptions governing its applicability to...

  6. Hidden gauge structure of supersymmetric free differential algebras

    NASA Astrophysics Data System (ADS)

    Andrianopoli, Laura; D'Auria, Riccardo; Ravera, Lucrezia

    2016-08-01

    The aim of this paper is to clarify the role of the nilpotent fermionic generator Q ' introduced in [6] and appearing in the hidden supergroup underlying the free differential algebra (FDA) of D=11 supergravity.

  7. Diagnostic Sampling to Reveal Hidden Lead and Copper Health Risks

    EPA Science Inventory

    Lead, copper and other metallic contamination sources in premise drinking water plumbing systems, are unevenly distributed and are usually hidden from thought, view, or both. Many sampling protocols exist, each with some set of implicit assumptions governing its applicability to...

  8. Energy Sector Market Analysis

    SciTech Connect

    Arent, D.; Benioff, R.; Mosey, G.; Bird, L.; Brown, J.; Brown, E.; Vimmerstedt, L.; Aabakken, J.; Parks, K.; Lapsa, M.; Davis, S.; Olszewski, M.; Cox, D.; McElhaney, K.; Hadley, S.; Hostick, D.; Nicholls, A.; McDonald, S.; Holloman, B.

    2006-10-01

    This paper presents the results of energy market analysis sponsored by the Department of Energy's (DOE) Weatherization and International Program (WIP) within the Office of Energy Efficiency and Renewable Energy (EERE). The analysis was conducted by a team of DOE laboratory experts from the National Renewable Energy Laboratory (NREL), Oak Ridge National Laboratory (ORNL), and Pacific Northwest National Laboratory (PNNL), with additional input from Lawrence Berkeley National Laboratory (LBNL). The analysis was structured to identify those markets and niches where government can create the biggest impact by informing management decisions in the private and public sectors. The analysis identifies those markets and niches where opportunities exist for increasing energy efficiency and renewable energy use.

  9. Exploring Oman's Energy Sector

    NASA Astrophysics Data System (ADS)

    Al-Saqlawi, Juman; Madani, Kaveh; Mac Dowell, Niall

    2016-04-01

    Located in a region where over 40% of the world's oil and gas reserves lie and in a trend similar to that of its neighbors, Oman's economy has been reliant on crude oil export since the 1970's. Being aware of the dangers of this reliance along with the discovery of Natural Gas since the 1980s, the Omani government's policy of diversifying its economy has shifted its reliance on Oil to another fossil fuel, namely Natural Gas. Given that energy is the lifeline of Oman's economy, effective and efficient forward planning and policy development is essential for the country's current and future economic development. This presentation explores the current status of the energy sector in Oman from home production and import to eventual final uses. The presentation highlights the major issues with Oman's current energy policies and suggests various strategies that could be adopted by Oman for a more efficient and sustainable future.

  10. The Hidden Curriculum: Exposing the Unintended Lessons of Medical Education

    PubMed Central

    Hopkins, Laura; Saciragic, Lana; Posner, Glenn

    2016-01-01

    Introduction: The hidden curriculum is a set of ethical, moral, and value-based teachings communicated to doctors-in-training, providing a basis for their future interactions with patients, peers, and colleagues. The aim of our study is to introduce the concept of the hidden curriculum to a cohort of third-year medical students and to subsequently evaluate their understanding. In particular, we sought to measure and benchmark the degree of hidden curriculum recognition within a Canadian medical education context. With the help of student feedback, we elicited ideas for future directions. Methods: One hundred and fifty-four third-year medical students completing their obstetrics and gynaecology core clinical rotation attended a workshop on the hidden curriculum. Students completed two sets of evaluations; a voluntary anonymous pre- and post-workshop questionnaire evaluating their knowledge and opinions regarding the hidden curriculum, and a mandatory workshop evaluation. Answers to pre- and post-workshop questionnaires were compared using Mann-Whitney U test, and thematic analysis was used to code the students’ comments to identify common themes. Results: A standardized workshop on the hidden curriculum significantly improved students’ understanding and highlighted the importance of the hidden curriculum. Voluntary student comments (N = 108) were categorized according to five themes:  1) Students who were not sensitized to the hidden curriculum (8; 7.4%); 2) students who were sensitized but unaware of the hidden curriculum (12; 11.1%); 3) students who were sensitized and aware of the hidden curriculum (34; 31.5%); 4) comments on teaching methodologies/environment (43; 39.8%); and 5) suggestions for enhancement (11; 10.2%). Conclusions: A simple, cost-effective intervention, such as a workshop, can effectively assess and address the hidden curriculum. Many students are highly sensitized to and are aware of the positive and negative effects of role modeling

  11. Uncertainty bounds using sector theory

    NASA Technical Reports Server (NTRS)

    Waszak, Martin R.; Schmidt, David K.

    1989-01-01

    An approach based on sector-stability theory can furnish a description of the uncertainty associated with the frequency response of a model, given sector-bounds on the individual parameters of the model. The application of the sector-based approach to the formulation of useful uncertainty descriptions for linear, time-invariant multivariable systems is presently explored, and the approach is applied to two generic forms of parameter uncertainty in order to investigate its advantages and limitations. The results obtained show that sector-uncertainty bounds can be used to evaluate the impact of parameter uncertainties on the frequency response of the design model.

  12. An integrated system for identifying the hidden assassins in traditional medicines containing aristolochic acids

    PubMed Central

    Wu, Lan; Sun, Wei; Wang, Bo; Zhao, Haiyu; Li, Yaoli; Cai, Shaoqing; Xiang, Li; Zhu, Yingjie; Yao, Hui; Song, Jingyuan; Cheng, Yung-Chi; Chen, Shilin

    2015-01-01

    Traditional herbal medicines adulterated and contaminated with plant materials from the Aristolochiaceae family, which contain aristolochic acids (AAs), cause aristolochic acid nephropathy. Approximately 256 traditional Chinese patent medicines, containing Aristolochiaceous materials, are still being sold in Chinese markets today. In order to protect consumers from health risks due to AAs, the hidden assassins, efficient methods to differentiate Aristolochiaceous herbs from their putative substitutes need to be established. In this study, 158 Aristolochiaceous samples representing 46 species and four genera as well as 131 non-Aristolochiaceous samples representing 33 species, 20 genera and 12 families were analyzed using DNA barcodes based on the ITS2 and psbA-trnH sequences. Aristolochiaceous materials and their non-Aristolochiaceous substitutes were successfully identified using BLAST1, the nearest distance method and the neighbor-joining (NJ) tree. In addition, based on sequence information of ITS2, we developed a Real-Time PCR assay which successfully identified herbal material from the Aristolochiaceae family. Using Ultra High Performance Liquid Chromatography-Mass Spectrometer (UHPLC-HR-MS), we demonstrated that most representatives from the Aristolochiaceae family contain toxic AAs. Therefore, integrated DNA barcodes, Real-Time PCR assays using TaqMan probes and UHPLC-HR-MS system provides an efficient and reliable authentication system to protect consumers from health risks due to the hidden assassins (AAs). PMID:26270958

  13. An integrated system for identifying the hidden assassins in traditional medicines containing aristolochic acids.

    PubMed

    Wu, Lan; Sun, Wei; Wang, Bo; Zhao, Haiyu; Li, Yaoli; Cai, Shaoqing; Xiang, Li; Zhu, Yingjie; Yao, Hui; Song, Jingyuan; Cheng, Yung-Chi; Chen, Shilin

    2015-08-13

    Traditional herbal medicines adulterated and contaminated with plant materials from the Aristolochiaceae family, which contain aristolochic acids (AAs), cause aristolochic acid nephropathy. Approximately 256 traditional Chinese patent medicines, containing Aristolochiaceous materials, are still being sold in Chinese markets today. In order to protect consumers from health risks due to AAs, the hidden assassins, efficient methods to differentiate Aristolochiaceous herbs from their putative substitutes need to be established. In this study, 158 Aristolochiaceous samples representing 46 species and four genera as well as 131 non-Aristolochiaceous samples representing 33 species, 20 genera and 12 families were analyzed using DNA barcodes based on the ITS2 and psbA-trnH sequences. Aristolochiaceous materials and their non-Aristolochiaceous substitutes were successfully identified using BLAST1, the nearest distance method and the neighbor-joining (NJ) tree. In addition, based on sequence information of ITS2, we developed a Real-Time PCR assay which successfully identified herbal material from the Aristolochiaceae family. Using Ultra High Performance Liquid Chromatography-Mass Spectrometer (UHPLC-HR-MS), we demonstrated that most representatives from the Aristolochiaceae family contain toxic AAs. Therefore, integrated DNA barcodes, Real-Time PCR assays using TaqMan probes and UHPLC-HR-MS system provides an efficient and reliable authentication system to protect consumers from health risks due to the hidden assassins (AAs).

  14. An integrated system for identifying the hidden assassins in traditional medicines containing aristolochic acids

    NASA Astrophysics Data System (ADS)

    Wu, Lan; Sun, Wei; Wang, Bo; Zhao, Haiyu; Li, Yaoli; Cai, Shaoqing; Xiang, Li; Zhu, Yingjie; Yao, Hui; Song, Jingyuan; Cheng, Yung-Chi; Chen, Shilin

    2015-08-01

    Traditional herbal medicines adulterated and contaminated with plant materials from the Aristolochiaceae family, which contain aristolochic acids (AAs), cause aristolochic acid nephropathy. Approximately 256 traditional Chinese patent medicines, containing Aristolochiaceous materials, are still being sold in Chinese markets today. In order to protect consumers from health risks due to AAs, the hidden assassins, efficient methods to differentiate Aristolochiaceous herbs from their putative substitutes need to be established. In this study, 158 Aristolochiaceous samples representing 46 species and four genera as well as 131 non-Aristolochiaceous samples representing 33 species, 20 genera and 12 families were analyzed using DNA barcodes based on the ITS2 and psbA-trnH sequences. Aristolochiaceous materials and their non-Aristolochiaceous substitutes were successfully identified using BLAST1, the nearest distance method and the neighbor-joining (NJ) tree. In addition, based on sequence information of ITS2, we developed a Real-Time PCR assay which successfully identified herbal material from the Aristolochiaceae family. Using Ultra High Performance Liquid Chromatography-Mass Spectrometer (UHPLC-HR-MS), we demonstrated that most representatives from the Aristolochiaceae family contain toxic AAs. Therefore, integrated DNA barcodes, Real-Time PCR assays using TaqMan probes and UHPLC-HR-MS system provides an efficient and reliable authentication system to protect consumers from health risks due to the hidden assassins (AAs).

  15. Colloquium: Hidden order, superconductivity, and magnetism: The unsolved case of URu2Si2

    NASA Astrophysics Data System (ADS)

    Mydosh, J. A.; Oppeneer, P. M.

    2011-10-01

    This Colloquium reviews the 25 year quest to understand the continuous (second-order), mean-field-like phase transition occurring at 17.5 K in URu2Si2. About ten years ago, the term “hidden order” (HO) was coined and has since been utilized to describe the unknown ordered state, whose origin cannot be disclosed by conventional solid-state probes, such as x rays, neutrons, or muons. The HO is able to support superconductivity at lower temperatures (Tc≈1.5K), and when magnetism is developed with increasing pressure both the HO and the superconductivity are destroyed. Other ways of probing the HO are via Rh doping and large magnetic fields. During the last few years a variety of advanced techniques have been tested to probe the HO state and these attempts will be summarized. A digest of recent theoretical developments is also included. It is the objective of this Colloquium to shed additional light on the HO state and its associated phases in other materials.

  16. Evidence Feed Forward Hidden Markov Model: A New Type of Hidden Markov Model

    DTIC Science & Technology

    2011-01-01

    have learning in them and rely on heavy processing of the data to determine the intent of the person. M . Cristani et al [1] uses non-traditional AI...Applications (IJAIA), Vol.2, No.1, January 2011 3 Template matching is performed by M . Dimitrijevic et. al. [2]. They developed a template...hidden nodes and M be the total number of observations. Let T be the total number of transitions (or time). Let state at time t is Si where 1 ≤ i

  17. Hidden Structural Codes in Protein Intrinsic Disorder.

    PubMed

    Borkosky, Silvia S; Camporeale, Gabriela; Chemes, Lucía B; Risso, Marikena; Noval, María Gabriela; Sánchez, Ignacio E; Alonso, Leonardo G; de Prat Gay, Gonzalo

    2017-10-06

    Intrinsic disorder is a major structural category in biology, accounting for more than 30% of coding regions across the domains of life, yet consists of conformational ensembles in equilibrium, a major challenge in protein chemistry. Anciently evolved papillomavirus genomes constitute an unparalleled case for sequence to structure-function correlation in cases in which there are no folded structures. E7, the major transforming oncoprotein of human papillomaviruses, is a paradigmatic example among the intrinsically disordered proteins. Analysis of a large number of sequences of the same viral protein allowed for the identification of a handful of residues with absolute conservation, scattered along the sequence of its N-terminal intrinsically disordered domain, which intriguingly are mostly leucine residues. Mutation of these led to a pronounced increase in both α-helix and β-sheet structural content, reflected by drastic effects on equilibrium propensities and oligomerization kinetics, and uncovers the existence of local structural elements that oppose canonical folding. These folding relays suggest the existence of yet undefined hidden structural codes behind intrinsic disorder in this model protein. Thus, evolution pinpoints conformational hot spots that could have not been identified by direct experimental methods for analyzing or perturbing the equilibrium of an intrinsically disordered protein ensemble.

  18. Homodyne impulse radar hidden object locator

    DOEpatents

    McEwan, Thomas E.

    1996-01-01

    An electromagnetic detector is designed to locate an object hidden behind a separator or a cavity within a solid object. The detector includes a PRF generator for generating 2 MHz pulses, a homodyne oscillator for generating a 2 kHz square wave, and for modulating the pulses from the PRF generator. A transmit antenna transmits the modulated pulses through the separator, and a receive antenna receives the signals reflected off the object. The receiver path of the detector includes a sample and hold circuit, an AC coupled amplifier which filters out DC bias level shifts in the sample and hold circuit, and a rectifier circuit connected to the homodyne oscillator and to the AC coupled amplifier, for synchronously rectifying the modulated pulses transmitted over the transmit antenna. The homodyne oscillator modulates the signal from the PRF generator with a continuous wave (CW) signal, and the AC coupled amplifier operates with a passband centered on that CW signal. The present detector can be used in several applications, including the detection of metallic and non-metallic objects, such as pipes, studs, joists, nails, rebars, conduits and electrical wiring, behind wood wall, ceiling, plywood, particle board, dense hardwood, masonry and cement structure. The detector is portable, light weight, simple to use, inexpensive, and has a low power emission which facilitates the compliance with Part 15 of the FCC rules.

  19. Homodyne impulse radar hidden object locator

    DOEpatents

    McEwan, T.E.

    1996-04-30

    An electromagnetic detector is designed to locate an object hidden behind a separator or a cavity within a solid object. The detector includes a PRF generator for generating 2 MHz pulses, a homodyne oscillator for generating a 2 kHz square wave, and for modulating the pulses from the PRF generator. A transmit antenna transmits the modulated pulses through the separator, and a receive antenna receives the signals reflected off the object. The receiver path of the detector includes a sample and hold circuit, an AC coupled amplifier which filters out DC bias level shifts in the sample and hold circuit, and a rectifier circuit connected to the homodyne oscillator and to the AC coupled amplifier, for synchronously rectifying the modulated pulses transmitted over the transmit antenna. The homodyne oscillator modulates the signal from the PRF generator with a continuous wave (CW) signal, and the AC coupled amplifier operates with a passband centered on that CW signal. The present detector can be used in several applications, including the detection of metallic and non-metallic objects, such as pipes, studs, joists, nails, rebars, conduits and electrical wiring, behind wood wall, ceiling, plywood, particle board, dense hardwood, masonry and cement structure. The detector is portable, light weight, simple to use, inexpensive, and has a low power emission which facilitates the compliance with Part 15 of the FCC rules. 15 figs.

  20. Hidden Markov models in automatic speech recognition

    NASA Astrophysics Data System (ADS)

    Wrzoskowicz, Adam

    1993-11-01

    This article describes a method for constructing an automatic speech recognition system based on hidden Markov models (HMMs). The author discusses the basic concepts of HMM theory and the application of these models to the analysis and recognition of speech signals. The author provides algorithms which make it possible to train the ASR system and recognize signals on the basis of distinct stochastic models of selected speech sound classes. The author describes the specific components of the system and the procedures used to model and recognize speech. The author discusses problems associated with the choice of optimal signal detection and parameterization characteristics and their effect on the performance of the system. The author presents different options for the choice of speech signal segments and their consequences for the ASR process. The author gives special attention to the use of lexical, syntactic, and semantic information for the purpose of improving the quality and efficiency of the system. The author also describes an ASR system developed by the Speech Acoustics Laboratory of the IBPT PAS. The author discusses the results of experiments on the effect of noise on the performance of the ASR system and describes methods of constructing HMM's designed to operate in a noisy environment. The author also describes a language for human-robot communications which was defined as a complex multilevel network from an HMM model of speech sounds geared towards Polish inflections. The author also added mandatory lexical and syntactic rules to the system for its communications vocabulary.

  1. Mitotic cell recognition with hidden Markov models

    NASA Astrophysics Data System (ADS)

    Gallardo, Greg M.; Yang, Fuxing; Ianzini, Fiorenza; Mackey, Michael; Sonka, Milan

    2004-05-01

    This work describes a method for detecting mitotic cells in time-lapse microscopy images of live cells. The image sequences are from the Large Scale Digital Cell Analysis System (LSDCAS) at the University of Iowa. LSDCAS is an automated microscope system capable of monitoring 1000 microscope fields over time intervals of up to one month. Manual analysis of the image sequences can be extremely time consuming. This work is part of a larger project to automate the image sequence analysis. A three-step approach is used. In the first step, potential mitotic cells are located in the image sequences. In the second step, object border segmentation is performed with the watershed algorithm. Objects in adjacent frames are grouped into object sequences for classification. In the third step, the image sequences are converted to feature vector sequences. The feature vectors contain spatial and temporal information. Hidden Markov Models (HMMs) are used to classify the feature vector sequences into dead cells, cell edges, and dividing cells. Discrete and continuous HMMs were trained on 500 sequences. The discrete HMM recognition rates were 62% for dead cells, 77% for cell edges, and 75% for dividing cells. The continuous HMM results were 68%, 88% and 77%.

  2. Uncovering hidden variation in polyploid wheat

    PubMed Central

    Krasileva, Ksenia V.; Vasquez-Gross, Hans A.; Howell, Tyson; Bailey, Paul; Paraiso, Francine; Clissold, Leah; Simmonds, James; Ramirez-Gonzalez, Ricardo H.; Wang, Xiaodong; Borrill, Philippa; Fosker, Christine; Ayling, Sarah; Phillips, Andrew L.; Uauy, Cristobal

    2017-01-01

    Comprehensive reverse genetic resources, which have been key to understanding gene function in diploid model organisms, are missing in many polyploid crops. Young polyploid species such as wheat, which was domesticated less than 10,000 y ago, have high levels of sequence identity among subgenomes that mask the effects of recessive alleles. Such redundancy reduces the probability of selection of favorable mutations during natural or human selection, but also allows wheat to tolerate high densities of induced mutations. Here we exploited this property to sequence and catalog more than 10 million mutations in the protein-coding regions of 2,735 mutant lines of tetraploid and hexaploid wheat. We detected, on average, 2,705 and 5,351 mutations per tetraploid and hexaploid line, respectively, which resulted in 35–40 mutations per kb in each population. With these mutation densities, we identified an average of 23–24 missense and truncation alleles per gene, with at least one truncation or deleterious missense mutation in more than 90% of the captured wheat genes per population. This public collection of mutant seed stocks and sequence data enables rapid identification of mutations in the different copies of the wheat genes, which can be combined to uncover previously hidden variation. Polyploidy is a central phenomenon in plant evolution, and many crop species have undergone recent genome duplication events. Therefore, the general strategy and methods developed herein can benefit other polyploid crops. PMID:28096351

  3. Coulomb gauge model for hidden charm tetraquarks

    NASA Astrophysics Data System (ADS)

    Xie, W.; Mo, L. Q.; Wang, Ping; Cotanch, Stephen R.

    2013-08-01

    The spectrum of tetraquark states with hidden charm is studied within an effective Coulomb gauge Hamiltonian approach. Of the four independent color schemes, two are investigated, the (qcbar)1(cqbar)1 singlet-singlet (molecule) and the (qc)3(qbarcbar)3 triplet-triplet (diquark), for selected JPC states using a variational method. The predicted masses of triplet-triplet tetraquarks are roughly a GeV heavier than the singlet-singlet states. There is also an interesting flavor dependence with (qqbar)1 (ccbar1) states about half a GeV lighter than (qcbar)1(qbarc)1. The lightest 1++ and 1-- predictions are in agreement with the observed X (3872) and Y (4008) masses suggesting they are molecules with ωJ / ψ and ηhc, rather than D*Dbar* and DDbar, type structure, respectively. Similarly, the lightest isovector 1++ molecule, having a ρJ / ψ flavor composition, has mass near the recently observed charged Zc (3900) value. These flavor configurations are consistent with observed X, Y and Zc decays to ππJ / ψ.

  4. A Hidden Portrait by Edgar Degas.

    PubMed

    Thurrowgood, David; Paterson, David; de Jonge, Martin D; Kirkham, Robin; Thurrowgood, Saul; Howard, Daryl L

    2016-08-04

    The preservation and understanding of cultural heritage depends increasingly on in-depth chemical studies. Rapid technological advances are forging connections between scientists and arts communities, enabling revolutionary new techniques for non-invasive technical study of culturally significant, highly prized artworks. We have applied a non-invasive, rapid, high definition X-ray fluorescence (XRF) elemental mapping technique to a French Impressionist painting using a synchrotron radiation source, and show how this technology can advance scholarly art interpretation and preservation. We have obtained detailed technical understanding of a painting which could not be resolved by conventional techniques. Here we show 31.6 megapixel scanning XRF derived elemental maps and report a novel image processing methodology utilising these maps to produce a false colour representation of a "hidden" portrait by Edgar Degas. This work provides a cohesive methodology for both imaging and understanding the chemical composition of artworks, and enables scholarly understandings of cultural heritage, many of which have eluded conventional technologies. We anticipate that the outcome from this work will encourage the reassessment of some of the world's great art treasures.

  5. Stochastic precipitation generator with hidden state covariates

    NASA Astrophysics Data System (ADS)

    Kim, Yongku; Lee, GyuWon

    2017-08-01

    Time series of daily weather such as precipitation, minimum temperature and maximum temperature are commonly required for various fields. Stochastic weather generators constitute one of the techniques to produce synthetic daily weather. The recently introduced approach for stochastic weather generators is based on generalized linear modeling (GLM) with covariates to account for seasonality and teleconnections (e.g., with the El Niño). In general, stochastic weather generators tend to underestimate the observed interannual variance of seasonally aggregated variables. To reduce this overdispersion, we incorporated time series of seasonal dry/wet indicators in the GLM weather generator as covariates. These seasonal time series were local (or global) decodings obtained by a hidden Markov model of seasonal total precipitation and implemented in the weather generator. The proposed method is applied to time series of daily weather from Seoul, Korea and Pergamino, Argentina. This method provides a straightforward translation of the uncertainty of the seasonal forecast to the corresponding conditional daily weather statistics.

  6. Fibromyalgia and obesity: the hidden link.

    PubMed

    Ursini, Francesco; Naty, Saverio; Grembiale, Rosa Daniela

    2011-11-01

    Fibromyalgia is a chronic disorder of uncertain etiology, characterized by widespread pain, muscle tenderness, and decreased pain threshold to pressure and other stimuli. Obesity is a well-known aggravating factor for certain rheumatologic conditions, such as knee osteoarthritis. Emerging evidences are exploring the link between obesity and other rheumatic diseases, such as fibromyalgia. Epidemiological data show that fibromyalgia patients have higher prevalence of obesity (40%) and overweight (30%) in multiple studies compared with healthy patients. Several mechanisms have been proposed to explain "the hidden link", but at this time is not possible to ascertain whether obesity is cause or consequence of fibromyalgia. Among mechanisms proposed, there are the following: impaired physical activity, cognitive and sleep disturbances, psychiatric comorbidity and depression, dysfunction of thyroid gland, dysfunction of the GH/IGF-1 axis, impairment of the endogenous opioid system. In this article, we review the scientific evidence supporting a possible link between obesity and fibromyalgia, how obesity influences fibromyalgia symptoms and how fibromyalgia severity can be improved by weight loss. In addition, we analyze the possible mechanisms by which fibromyalgia and obesity interrelate.

  7. Unveiling hidden patterns in CMB anisotropy maps

    SciTech Connect

    Ghosh, Tuhin; Souradeep, Tarun; Hajian, Amir

    2007-04-15

    Bianchi VII{sub h} models have been recently proposed to explain potential anomalies in the CMB anisotropy as observed by WMAP. We investigate the violation of statistical isotropy due to an embedded Bianchi VII{sub h} template in the CMB anisotropy maps to determine whether the existence of a hidden Bianchi template in the WMAP data is consistent with the previous null detection of the bipolar power spectrum in the WMAP first-year maps. We argue that, although correcting the WMAP maps for the Bianchi template may explain some features in the WMAP data, it may cause other anomalies such as preferred directions leading to detectable levels of violation of statistical isotropy in the Bianchi corrected maps. We compute the bipolar power spectrum for the low density Bianchi VII{sub h} models embedded in the background CMB anisotropy maps with the power spectrum that have been shown in recent literature to best fit the first-year WMAP data. By examining the statistical isotropy of these maps, we put a limit of (({sigma}/H)){sub 0}{<=}2.77x10{sup -10}(99% C.L.) on the shear parameter in Bianchi VII{sub h} models.

  8. Seiberg duality versus hidden local symmetry

    NASA Astrophysics Data System (ADS)

    Abel, Steven; Barnard, James

    2012-05-01

    It is widely believed that the emergent magnetic gauge symmetry of SQCD is analogous to a hidden local symmetry (HLS). We explore this idea in detail, deriving the entire (spontaneously broken) magnetic theory by applying the HLS formalism to spontaneously broken SU( N) SQCD. We deduce the Kähler potential in the HLS description, and show that gauge and flavour symmetry are smoothly restored along certain scaling directions in moduli space. We propose that it is these symmetry restoring directions, associated with the R-symmetry of the theory, that allow full Seiberg duality. Reconsidering the origin of the magnetic gauge bosons as the ρ-mesons of the electric theory, colour-flavour locking allows a simple determination of the parameter a. Its value continuously interpolates between a = 2 on the baryonic branch of moduli space — corresponding to "vector meson dominance" — and a = 1 on the mesonic branch. Both limiting values are consistent with previous results in the literature. The HLS formalism is further applied to SO and Sp groups, where the usual Seiberg duals are recovered, as well as adjoint SQCD. Finally we discuss some possible future applications, including (naturally) the unitarisation of composite W scattering, blended Higgs/technicolour models, real world QCD and non-supersymmetric dualities.

  9. Academic mobbing: hidden health hazard at workplace.

    PubMed

    Khoo, Sb

    2010-01-01

    Academic mobbing is a non-violent, sophisticated, 'ganging up' behaviour adopted by academicians to "wear and tear" a colleague down emotionally through unjustified accusation, humiliation, general harassment and emotional abuse. These are directed at the target under a veil of lies and justifications so that they are "hidden" to others and difficult to prove. Bullies use mobbing activities to hide their own weaknesses and incompetence. Targets selected are often intelligent, innovative high achievers, with good integrity and principles. Mobbing activities appear trivial and innocuous on its own but the frequency and pattern of their occurrence over long period of time indicates an aggressive manipulation to "eliminate" the target. Mobbing activities typically progress through five stereotypical phases that begins with an unsolved minor conflict between two workers and ultimately escalates into a senseless mobbing whereby the target is stigmatized and victimized to justify the behaviours of the bullies. The result is always physical, mental, social distress or illness and, most often, expulsion of target from the workplace. Organizations are subjected to great financial loss, loss of key workers and a tarnished public image and reputation. Public awareness, education, effective counselling, establishment of anti-bullying policies and legislations at all levels are necessary to curb academic mobbing. General practitioners (GPs) play an important role in supporting patients subjected to mental and physical health injury caused by workplace bullying and mobbing.

  10. Stochastic motif extraction using hidden Markov model

    SciTech Connect

    Fujiwara, Yukiko; Asogawa, Minoru; Konagaya, Akihiko

    1994-12-31

    In this paper, we study the application of an HMM (hidden Markov model) to the problem of representing protein sequences by a stochastic motif. A stochastic protein motif represents the small segments of protein sequences that have a certain function or structure. The stochastic motif, represented by an HMM, has conditional probabilities to deal with the stochastic nature of the motif. This HMM directive reflects the characteristics of the motif, such as a protein periodical structure or grouping. In order to obtain the optimal HMM, we developed the {open_quotes}iterative duplication method{close_quotes} for HMM topology learning. It starts from a small fully-connected network and iterates the network generation and parameter optimization until it achieves sufficient discrimination accuracy. Using this method, we obtained an HMM for a leucine zipper motif. Compared to the accuracy of a symbolic pattern representation with accuracy of 14.8 percent, an HMM achieved 79.3 percent in prediction. Additionally, the method can obtain an HMM for various types of zinc finger motifs, and it might separate the mixed data. We demonstrated that this approach is applicable to the validation of the protein databases; a constructed HMM b as indicated that one protein sequence annotated as {open_quotes}lencine-zipper like sequence{close_quotes} in the database is quite different from other leucine-zipper sequences in terms of likelihood, and we found this discrimination is plausible.

  11. Hidden Staphylococcus aureus Carriage: Overrated or Underappreciated?

    PubMed Central

    2016-01-01

    ABSTRACT Staphylococcus aureus is a persistent companion bacterial species in one-third of humankind. Reservoirs include the nasal and nasopharyngeal cavities, skin, and gastrointestinal (GI) tract. Despite earlier claims that colonization of individuals is caused by clonal organisms, next-generation sequencing (NGS) has revealed that resident type heterogeneity is not exceptional. Carriage, whether overt or hidden, is correlated with a risk of autoinfection. In a recent article in mBio, it was shown that, based on staphylococcal genome sequencing, low-level GI persistence may cause long-term nosocomial outbreaks [L. Senn et al., 7(1):e02039-15, 2016, doi:10.1128/mBio.02039-15]. Institutional endemicity with methicillin-resistant S. aureus (MRSA) sequence type 228 (ST228) is shown to originate not from high-level nasal carriage or poor compliance with infection control practice but from low-grade asymptomatic GI colonization. This shows the power of NGS in elucidating staphylococcal epidemiology and, even more important, demonstrates that (drug-resistant) microorganisms may possess stealthy means of persistence. Identifying these persistence mechanisms is key to successful infection control. PMID:26884429

  12. Phase transitions in Hidden Markov Models

    NASA Astrophysics Data System (ADS)

    Bechhoefer, John; Lathouwers, Emma

    In Hidden Markov Models (HMMs), a Markov process is not directly accessible. In the simplest case, a two-state Markov model ``emits'' one of two ``symbols'' at each time step. We can think of these symbols as noisy measurements of the underlying state. With some probability, the symbol implies that the system is in one state when it is actually in the other. The ability to judge which state the system is in sets the efficiency of a Maxwell demon that observes state fluctuations in order to extract heat from a coupled reservoir. The state-inference problem is to infer the underlying state from such noisy measurements at each time step. We show that there can be a phase transition in such measurements: for measurement error rates below a certain threshold, the inferred state always matches the observation. For higher error rates, there can be continuous or discontinuous transitions to situations where keeping a memory of past observations improves the state estimate. We can partly understand this behavior by mapping the HMM onto a 1d random-field Ising model at zero temperature. We also present more recent work that explores a larger parameter space and more states. Research funded by NSERC, Canada.

  13. QCD sum rule study of hidden-charm pentaquarks

    NASA Astrophysics Data System (ADS)

    Chen, Hua-Xing; Cui, Er-Liang; Chen, Wei; Liu, Xiang; Steele, T. G.; Zhu, Shi-Lin

    2016-10-01

    We study the mass spectra of hidden-charm pentaquarks having spin J = {1over 2}/{3over 2}/{5over 2} and quark contents uud c bar{c}. We systematically construct all the relevant local hidden-charm pentaquark currents, and we select some of them to perform QCD sum rule analyses. We find that the P_c(4380) and P_c(4450) can be identified as hidden-charm pentaquark states composed of an anti-charmed meson and a charmed baryon. Besides them, we also find (a) the lowest-lying hidden-charm pentaquark state of J^P = 1/2^- has the mass 4.33^{+0.17}_{-0.13} GeV, while the one of J^P = 1/2^+ is significantly higher, that is, around 4.7-4.9 GeV; (b) the lowest-lying hidden-charm pentaquark state of J^P = 3/2^- has the mass 4.37^{+0.18}_{-0.13} GeV, consistent with the P_c(4380) of J^P = 3/2^-, while the one of J^P = 3/2^+ is also significantly higher, that is, above 4.6 GeV; (c) the hidden-charm pentaquark state of J^P = 5/2^- has a mass around 4.5-4.6 GeV, slightly larger than the P_c(4450) of J^P = 5/2^+.

  14. A tale of two portals: testing light, hidden new physics at future e + e - colliders

    NASA Astrophysics Data System (ADS)

    Liu, Jia; Wang, Xiao-Ping; Yu, Felix

    2017-06-01

    We investigate the prospects for producing new, light, hidden states at a future e + e - collider in a Higgsed dark U(1) D model, which we call the Double Dark Portal model. The simultaneous presence of both vector and scalar portal couplings immediately modifies the Standard Model Higgsstrahlung channel, e + e - → Zh, at leading order in each coupling. In addition, each portal leads to complementary signals which can be probed at direct and indirect detection dark matter experiments. After accounting for current constraints from LEP and LHC, we demonstrate that a future e + e - Higgs factory will have unique and leading sensitivity to the two portal couplings by studying a host of new production, decay, and radiative return processes. Besides the possibility of exotic Higgs decays, we highlight the importance of direct dark vector and dark scalar production at e + e - machines, whose invisible decays can be tagged from the recoil mass method.

  15. Local suppression of the hidden-order phase by impurities in URu2Si2

    NASA Astrophysics Data System (ADS)

    Pezzoli, Maria E.; Graf, Matthias J.; Haule, Kristjan; Kotliar, Gabriel; Balatsky, Alexander V.

    2011-06-01

    We consider the effects of impurities on the enigmatic hidden order (HO) state of the heavy-fermion material URu2Si2. In particular, we focus on local effects of Rh impurities as a tool to probe the suppression of the HO state. To study local properties, we introduce a lattice free energy, where the time invariant HO order parameter Ψ and local antiferromagnetic (AFM) order parameter M are competing orders. Near each Rh atom, the HO order parameter is suppressed, creating a hole in which local AFM order emerges as a result of competition. These local holes are created in the fabric of the HO state like in a Swiss cheese and “filled” with droplets of AFM order. We compare our analysis with recent NMR results on U(RhxRu1-x)2Si2 and find good agreement with the data.

  16. A Holding Function for Conflict Probe Appiications

    NASA Technical Reports Server (NTRS)

    McNally, Dave; Walton, Joe

    2004-01-01

    Conflict Alerts for aircraft in holding patterns are often missed or in error due to fact that holding trajectories are not modeled in Conflict Alert or Conflict Probe logic. In addition, a controller in one sector may not know when aircraft are holding in a neighboring sector. These factors can lead to an increased potential for loss of separation while aircraft are flying in holding patterns. A holding function for conflict probe applications has been developed and tested with air traffic data from Fort Worth Center. The holding function automatically determines when an aircraft enters a holding pattern, builds a holding region around the pattern and then probes the region for conflict with other traffic. The operational concept of use assumes that air traffic controllers are very busy during periods when aircraft are in holding and therefore don't have time to manually enter information which defines a holding pattern and activates conflict probing. For this reason, it is important the holding function automatically detect aircraft in holding and compute a holding region for conflict analysis. The controller is then alerted if other aircraft are predicted to fly through the holding region at the holding altitude.

  17. A Holding Function for Conflict Probe Appiications

    NASA Technical Reports Server (NTRS)

    McNally, Dave; Walton, Joe

    2004-01-01

    Conflict Alerts for aircraft in holding patterns are often missed or in error due to fact that holding trajectories are not modeled in Conflict Alert or Conflict Probe logic. In addition, a controller in one sector may not know when aircraft are holding in a neighboring sector. These factors can lead to an increased potential for loss of separation while aircraft are flying in holding patterns. A holding function for conflict probe applications has been developed and tested with air traffic data from Fort Worth Center. The holding function automatically determines when an aircraft enters a holding pattern, builds a holding region around the pattern and then probes the region for conflict with other traffic. The operational concept of use assumes that air traffic controllers are very busy during periods when aircraft are in holding and therefore don't have time to manually enter information which defines a holding pattern and activates conflict probing. For this reason, it is important the holding function automatically detect aircraft in holding and compute a holding region for conflict analysis. The controller is then alerted if other aircraft are predicted to fly through the holding region at the holding altitude.

  18. Informatic analysis for hidden pulse attack exploiting spectral characteristics of optics in plug-and-play quantum key distribution system

    NASA Astrophysics Data System (ADS)

    Ko, Heasin; Lim, Kyongchun; Oh, Junsang; Rhee, June-Koo Kevin

    2016-10-01

    Quantum channel loopholes due to imperfect implementations of practical devices expose quantum key distribution (QKD) systems to potential eavesdropping attacks. Even though QKD systems are implemented with optical devices that are highly selective on spectral characteristics, information theory-based analysis about a pertinent attack strategy built with a reasonable framework exploiting it has never been clarified. This paper proposes a new type of trojan horse attack called hidden pulse attack that can be applied in a plug-and-play QKD system, using general and optimal attack strategies that can extract quantum information from phase-disturbed quantum states of eavesdropper's hidden pulses. It exploits spectral characteristics of a photodiode used in a plug-and-play QKD system in order to probe modulation states of photon qubits. We analyze the security performance of the decoy-state BB84 QKD system under the optimal hidden pulse attack model that shows enormous performance degradation in terms of both secret key rate and transmission distance.

  19. Partnership in Sector Wide Approaches

    ERIC Educational Resources Information Center

    Tolley, Hilary

    2011-01-01

    Within the context of bilateral support to the education sector in Tonga and the Solomon Islands, this paper will explore how the discourse of "partnership" has been interpreted and activated within the Sector wide approach (SWAp). In concentrating particularly on the relationship between the respective Ministries of Education and New…

  20. Future Trends in Children's Web Pages: Probing Hidden Biases for Information Quality

    ERIC Educational Resources Information Center

    Kurubacak, Gulsun

    2007-01-01

    As global digital communication continues to flourish, Children's Web pages become more critical for children to realize not only the surface but also breadth and deeper meanings in presenting these milieus. These pages not only are very diverse and complex but also enable intense communication across social, cultural and political restrictions…

  1. Future Trends in Chlldren's Web Pages: Probing Hidden Biases for Information Quality

    ERIC Educational Resources Information Center

    Kurubacak, Gulsun

    2007-01-01

    As global digital communication continues to flourish, Children's Web pages become more critical for children to realize not only the surface but also breadth and deeper meanings in presenting these milieus. These pages not only are very diverse and complex but also enable intense communication across social, cultural and political restrictions…

  2. Future Trends in Chlldren's Web Pages: Probing Hidden Biases for Information Quality

    ERIC Educational Resources Information Center

    Kurubacak, Gulsun

    2007-01-01

    As global digital communication continues to flourish, Children's Web pages become more critical for children to realize not only the surface but also breadth and deeper meanings in presenting these milieus. These pages not only are very diverse and complex but also enable intense communication across social, cultural and political restrictions…

  3. Hidden Mott transition and large-U superconductivity in the two-dimensional Hubbard model

    NASA Astrophysics Data System (ADS)

    Tocchio, Luca F.; Becca, Federico; Sorella, Sandro

    2016-11-01

    We consider the one-band Hubbard model on the square lattice by using variational and Green's function Monte Carlo methods, where the variational states contain Jastrow and backflow correlations on top of an uncorrelated wave function that includes BCS pairing and magnetic order. At half-filling, where the ground state is antiferromagnetically ordered for any value of the on-site interaction U , we can identify a hidden critical point UMott, above which a finite BCS pairing is stabilized in the wave function. The existence of this point is reminiscent of the Mott transition in the paramagnetic sector and determines a separation between a Slater insulator (at small values of U ), where magnetism induces a potential energy gain, and a Mott insulator (at large values of U ), where magnetic correlations drive a kinetic energy gain. Most importantly, the existence of UMott has crucial consequences when doping the system: We observe a tendency for phase separation into hole-rich and hole-poor regions only when doping the Slater insulator, while the system is uniform by doping the Mott insulator. Superconducting correlations are clearly observed above UMott, leading to the characteristic dome structure in doping. Furthermore, we show that the energy gain due to the presence of a finite BCS pairing above UMott shifts from the potential to the kinetic sector by increasing the value of the Coulomb repulsion.

  4. Foundational Forces & Hidden Variables in Technology Commercialization

    NASA Astrophysics Data System (ADS)

    Barnett, Brandon

    2011-03-01

    The science of physics seems vastly different from the process of technology commercialization. Physics strives to understand our world through the experimental deduction of immutable laws and dependent variables and the resulting macro-scale phenomenon. In comparison, the~goal of business is to make a profit by addressing the needs, preferences, and whims of individuals in a market. It may seem that this environment is too dynamic to identify all the hidden variables and deduct the foundational forces that impact a business's ability to commercialize innovative technologies. One example of a business ``force'' is found in the semiconductor industry. In 1965, Intel co-founder Gordon Moore predicted that the number of transistors incorporated in a chip will approximately double every 24 months. Known as Moore's Law, this prediction has become the guiding principle for the semiconductor industry for the last 40 years. Of course, Moore's Law is not really a law of nature; rather it is the result of efforts by Intel and the entire semiconductor industry. A closer examination suggests that there are foundational principles of business that underlie the macro-scale phenomenon of Moore's Law. Principles of profitability, incentive, and strategic alignment have resulted in a coordinated influx of resources that has driven technologies to market, increasing the profitability of the semiconductor industry and optimizing the fitness of its participants. New innovations in technology are subject to these same principles. So, in addition to traditional market forces, these often unrecognized forces and variables create challenges for new technology commercialization. In this talk, I will draw from ethnographic research, complex adaptive theory, and industry data to suggest a framework with which to think about new technology commercialization. Intel's bio-silicon initiative provides a case study.

  5. Hydrogeophysical investigations at Hidden Dam, Raymond, California

    USGS Publications Warehouse

    Minsley, Burke J.; Burton, Bethany; Ikard, Scott; Powers, Michael H.

    2011-01-01

    Self-potential and direct current resistivity surveys are carried out at the Hidden Dam site in Raymond, California to assess present-day seepage patterns and better understand the hydrogeologic mechanisms that likely influence seepage. Numerical modeling is utilized in conjunction with the geophysical measurements to predict variably-saturated flow through typical two-dimensional dam cross-sections as a function of reservoir elevation. Several different flow scenarios are investigated based on the known hydrogeology, as well as information about typical subsurface structures gained from the resistivity survey. The flow models are also used to simulate the bulk electrical resistivity in the subsurface under varying saturation conditions, as well as the self-potential response using petrophysical relationships and electrokinetic coupling equations.The self-potential survey consists of 512 measurements on the downstream area of the dam, and corroborates known seepage areas on the northwest side of the dam. Two direct-current resistivity profiles, each approximately 2,500 ft (762 m) long, indicate a broad sediment channel under the northwest side of the dam, which may be a significant seepage pathway through the foundation. A focusing of seepage in low-topography areas downstream of the dam is confirmed from the numerical flow simulations, which is also consistent with past observations. Little evidence of seepage is identified from the self-potential data on the southeast side of the dam, also consistent with historical records, though one possible area of focused seepage is identified near the outlet works. Integration of the geophysical surveys, numerical modeling, and observation well data provides a framework for better understanding seepage at the site through a combined hydrogeophysical approach.

  6. Measuring the Hidden Aspects of Solar Magnetism

    NASA Astrophysics Data System (ADS)

    Stenflo, J. O.

    2008 marks the 100th anniversary of the discovery of astrophysical magnetic fields, when George Ellery Hale recorded the Zeeman splitting of spectral lines in sunspots. With the introduction of Babcock's photoelectric magnetograph, it soon became clear that the Sun's magnetic field outside sunspots is extremely structured. The field strengths that were measured were found to get larger when the spatial resolutionwas improved. It was therefore necessary to come up with methods to go beyond the spatial resolution limit and diagnose the intrinsic magnetic-field properties without dependence on the quality of the telescope used. The line-ratio technique that was developed in the early 1970s revealed a picture where most flux that we see in magnetograms originates in highly bundled, kG fields with a tiny volume filling factor. This led to interpretations in terms of discrete, strong-field magnetic flux tubes embedded in a rather field-free medium, and a whole industry of flux tube models at increasing levels of sophistication. This magnetic-field paradigm has now been shattered with the advent of high-precision imaging polarimeters that allow us to apply the so-called "Second Solar Spectrum" to diagnose aspects of solar magnetism that have been hidden to Zeeman diagnostics. It is found that the bulk of the photospheric volume is seething with intermediately strong, tangled fields. In the new paradigm, the field behaves like a fractal with a high degree of self-similarity, spanning about 8 orders of magnitude in scale size, down to scales of order 10m.

  7. Peptide crystal simulations reveal hidden dynamics

    PubMed Central

    Janowski, Pawel A.; Cerutti, David S.; Holton, James; Case, David A.

    2013-01-01

    Molecular dynamics simulations of biomolecular crystals at atomic resolution have the potential to recover information on dynamics and heterogeneity hidden in the X-ray diffraction data. We present here 9.6 microseconds of dynamics in a small helical peptide crystal with 36 independent copies of the unit cell. The average simulation structure agrees with experiment to within 0.28 Å backbone and 0.42 Å all-atom rmsd; a model refined against the average simulation density agrees with the experimental structure to within 0.20 Å backbone and 0.33 Å all-atom rmsd. The R-factor between the experimental structure factors and those derived from this unrestrained simulation is 23% to 1.0 Å resolution. The B-factors for most heavy atoms agree well with experiment (Pearson correlation of 0.90), but B-factors obtained by refinement against the average simulation density underestimate the coordinate fluctuations in the underlying simulation where the simulation samples alternate conformations. A dynamic flow of water molecules through channels within the crystal lattice is observed, yet the average water density is in remarkable agreement with experiment. A minor population of unit cells is characterized by reduced water content, 310 helical propensity and a gauche(−) side-chain rotamer for one of the valine residues. Careful examination of the experimental data suggests that transitions of the helices are a simulation artifact, although there is indeed evidence for alternate valine conformers and variable water content. This study highlights the potential for crystal simulations to detect dynamics and heterogeneity in experimental diffraction data, as well as to validate computational chemistry methods. PMID:23631449

  8. Hidden burden of malaria in Indian women

    PubMed Central

    2009-01-01

    Malaria is endemic in India with an estimated 70-100 million cases each year (1.6-1.8 million reported by NVBDCP); of this 50-55% are Plasmodium vivax and 45-50% Plasmodium falciparum. A recent study on malaria in pregnancy reported from undivided Madhya Pradesh state (includes Chhattisgarh state), that an estimated over 220,000 pregnant women contract malaria infection each year. Malaria in pregnancy caused- abortions 34.5%; stillbirths 9%; and maternal deaths 0.45%. Bulk of this tragic outcome can be averted by following the Roll Back Malaria/WHO recommendations of the use of malaria prevention i.e. indoor residual spraying (IRS)/insecticide-treated bed nets (ITN) preferably long-lasting treated bed nets (LLIN); intermittent preventive therapy (IPT); early diagnosis, prompt and complete treatment using microscopic/malaria rapid diagnostics test (RDT) and case management. High incidence in pregnancy has arisen because of malaria surveillance lacking coverage, lack of age and sex wise data, staff shortages, and intermittent preventive treatment (IPT) applicable in high transmission states/pockets is not included in the national drug policy- an essential component of fighting malaria in pregnancy in African settings. Inadequate surveillance and gross under-reporting has been highlighted time and again for over three decades. As a result the huge problem of malaria in pregnancy reported occasionally by researchers has remained hidden. Malaria in pregnancy may quicken severity in patients with drug resistant parasites, anaemia, endemic poverty, and malnutrition. There is, therefore, urgent need to streamline malaria control strategies to make a difference in tackling this grim scenario in human health. PMID:19995437

  9. Identifying hidden voice and video streams

    NASA Astrophysics Data System (ADS)

    Fan, Jieyan; Wu, Dapeng; Nucci, Antonio; Keralapura, Ram; Gao, Lixin

    2009-04-01

    Given the rising popularity of voice and video services over the Internet, accurately identifying voice and video traffic that traverse their networks has become a critical task for Internet service providers (ISPs). As the number of proprietary applications that deliver voice and video services to end users increases over time, the search for the one methodology that can accurately detect such services while being application independent still remains open. This problem becomes even more complicated when voice and video service providers like Skype, Microsoft, and Google bundle their voice and video services with other services like file transfer and chat. For example, a bundled Skype session can contain both voice stream and file transfer stream in the same layer-3/layer-4 flow. In this context, traditional techniques to identify voice and video streams do not work. In this paper, we propose a novel self-learning classifier, called VVS-I , that detects the presence of voice and video streams in flows with minimum manual intervention. Our classifier works in two phases: training phase and detection phase. In the training phase, VVS-I first extracts the relevant features, and subsequently constructs a fingerprint of a flow using the power spectral density (PSD) analysis. In the detection phase, it compares the fingerprint of a flow to the existing fingerprints learned during the training phase, and subsequently classifies the flow. Our classifier is not only capable of detecting voice and video streams that are hidden in different flows, but is also capable of detecting different applications (like Skype, MSN, etc.) that generate these voice/video streams. We show that our classifier can achieve close to 100% detection rate while keeping the false positive rate to less that 1%.

  10. Primary Dentition Analysis: Exploring a Hidden Approach

    PubMed Central

    Vanjari, Kalasandhya; Kamatham, Rekhalakshmi; Gaddam, Kumar Raja

    2016-01-01

    ABSTRACT Background: Accurate prediction of the mesiodistal widths (MDWs) of canines and premolars in children with primary dentition facilitates interception of malocclusion at an early age. Boston University (BU) approach is one, i.e., based on primary teeth for predicting canine and premolar dimensions. Aim: To predict the canine and premolar dimensions, in the contemporary population, using BU approach and compare with the values obtained using Tanaka-Johnston (T/J) approach. Design: Children in the age range of 7-11 years with presence of all permanent mandibular incisors and primary maxillary and mandibular canines and first molars were included in the study. Those with interproximal caries or restorations, abnormalities in shape or size and history of orthodontic treatment were excluded. Impressions of both arches were made using irreversible hydrocolloid and poured with dental stone. The MDWs of the required teeth were measured on the models using electronic digital vernier caliper from which widths of permanent canines and premolars were predicted using both T/J and BU approaches. Results: Statistically significant (p = 0.00) positive correlation (r = 0.52-0.55) was observed between T/J and BU approaches. A statistically significant (p = 0.00) strong positive correlation (r = 0.72-0.77) was observed among girls, whereas boys showed a statistically nonsignificant weak positive correlation (r=0.17-0.42) based on gender. Conclusion: Boston University approach can be further studied prospectively to make it possible as a prediction method of permanent tooth dimensions for children in primary dentition stage. How to cite this article: Nuvvula S, Vanjari K, Kamatham R, Gaddam KR. Primary Dentition Analysis: Exploring a Hidden Approach. Int J Clin Pediatr Dent 2016;9(1):1-4. PMID:27274146

  11. VISTA Captures Celestial Cat's Hidden Secrets

    NASA Astrophysics Data System (ADS)

    2010-04-01

    The Cat's Paw Nebula, NGC 6334, is a huge stellar nursery, the birthplace of hundreds of massive stars. In a magnificent new ESO image taken with the Visible and Infrared Survey Telescope for Astronomy (VISTA) at the Paranal Observatory in Chile, the glowing gas and dust clouds obscuring the view are penetrated by infrared light and some of the Cat's hidden young stars are revealed. Towards the heart of the Milky Way, 5500 light-years from Earth in the constellation of Scorpius (the Scorpion), the Cat's Paw Nebula stretches across 50 light-years. In visible light, gas and dust are illuminated by hot young stars, creating strange reddish shapes that give the object its nickname. A recent image by ESO's Wide Field Imager (WFI) at the La Silla Observatory (eso1003) captured this visible light view in great detail. NGC 6334 is one of the most active nurseries of massive stars in our galaxy. VISTA, the latest addition to ESO's Paranal Observatory in the Chilean Atacama Desert, is the world's largest survey telescope (eso0949). It works at infrared wavelengths, seeing right through much of the dust that is such a beautiful but distracting aspect of the nebula, and revealing objects hidden from the sight of visible light telescopes. Visible light tends to be scattered and absorbed by interstellar dust, but the dust is nearly transparent to infrared light. VISTA has a main mirror that is 4.1 metres across and it is equipped with the largest infrared camera on any telescope. It shares the spectacular viewing conditions with ESO's Very Large Telescope (VLT), which is located on the nearby summit. With this powerful instrument at their command, astronomers were keen to see the birth pains of the big young stars in the Cat's Paw Nebula, some nearly ten times the mass of the Sun. The view in the infrared is strikingly different from that in visible light. With the dust obscuring the view far less, they can learn much more about how these stars form and develop in their first

  12. Increased taxon sampling reveals thousands of hidden orthologs in flatworms.

    PubMed

    Martín-Durán, José M; Ryan, Joseph F; Vellutini, Bruno C; Pang, Kevin; Hejnol, Andreas

    2017-07-01

    Gains and losses shape the gene complement of animal lineages and are a fundamental aspect of genomic evolution. Acquiring a comprehensive view of the evolution of gene repertoires is limited by the intrinsic limitations of common sequence similarity searches and available databases. Thus, a subset of the gene complement of an organism consists of hidden orthologs, i.e., those with no apparent homology to sequenced animal lineages-mistakenly considered new genes-but actually representing rapidly evolving orthologs or undetected paralogs. Here, we describe Leapfrog, a simple automated BLAST pipeline that leverages increased taxon sampling to overcome long evolutionary distances and identify putative hidden orthologs in large transcriptomic databases by transitive homology. As a case study, we used 35 transcriptomes of 29 flatworm lineages to recover 3427 putative hidden orthologs, some unidentified by OrthoFinder and HaMStR, two common orthogroup inference algorithms. Unexpectedly, we do not observe a correlation between the number of putative hidden orthologs in a lineage and its "average" evolutionary rate. Hidden orthologs do not show unusual sequence composition biases that might account for systematic errors in sequence similarity searches. Instead, gene duplication with divergence of one paralog and weak positive selection appear to underlie hidden orthology in Platyhelminthes. By using Leapfrog, we identify key centrosome-related genes and homeodomain classes previously reported as absent in free-living flatworms, e.g., planarians. Altogether, our findings demonstrate that hidden orthologs comprise a significant proportion of the gene repertoire in flatworms, qualifying the impact of gene losses and gains in gene complement evolution. © 2017 Martín-Durán et al.; Published by Cold Spring Harbor Laboratory Press.

  13. Hot-wire probe

    NASA Technical Reports Server (NTRS)

    Mikulla, V.

    1976-01-01

    High-temperature platinum probe measures turbulence and Reynolds shear stresses in high-temperature compressible flows. Probe does not vibrate at high velocities and does not react like strain gage on warmup.

  14. A Magnetoresistance Measuring Probe.

    DTIC Science & Technology

    The in line four point probe, commonly used for measuring the sheet resistance in a conductor, cannot measure the anisotropic ferromagnetic magnetoresistance. However, the addition of two contact points that are not collinear with the current contacts give the probe the ability to non-destructively measure the anistropic magnetoresistance. Keywords: Magnetoresistance; Anisotropic; Thin-Film; Permalloy; Four Point Probe; Anisotropic Resistance.

  15. Galileo Probe Battery System

    NASA Technical Reports Server (NTRS)

    Dagarin, B. P.; Taenaka, R. K.; Stofel, E. J.

    1997-01-01

    The conclusions of the Galileo probe battery system are: the battery performance met mission requirements with margin; extensive ground-based and flight tests of batteries prior to probe separation from orbiter provided good prediction of actual entry performance at Jupiter; and the Li-SO2 battery was an important choice for the probe's main power.

  16. Three Dimensional Sector Design with Optimal Number of Sectors

    NASA Technical Reports Server (NTRS)

    Xue, Min

    2009-01-01

    The concept of dynamic sector design suggests a strategic approach to ease air traffic congestion, which is predicted to become a serious problem in the national airspace system by 2025. Considerable research has been conducted to address the sectorization problem. In previous work, an approach that combines the Voronoi diagrams, Genetic Algorithms (GA), and the iterative deepening algorithm was proposed. However, as originally formulated, the number of sectors used was predefined and only two-dimensional partitions were allowed, which constrained the method's ability to achieve good designs. The current work extends the earlier Voronoi-based method by treating the number of sectors as an additional decision variable, allowing 3D partitions, and developing more comprehensive costs.

  17. Probing the braneworld hypothesis with a neutron-shining-through-a-wall experiment

    NASA Astrophysics Data System (ADS)

    Sarrazin, Michaël; Pignol, Guillaume; Lamblin, Jacob; Petit, Fabrice; Terwagne, Guy; Nesvizhevsky, Valery V.

    2015-04-01

    The possibility for our visible world to be a 3-brane embedded in a multidimensional bulk is at the heart of many theoretical edifices in high-energy physics. Probing the braneworld hypothesis is thus a major experimental challenge. Following recent theoretical works showing that matter swapping between braneworlds can occur, we propose a neutron-shining-through-a-wall experiment. We first show that an intense neutron source such as a nuclear reactor core can induce a hidden neutron flux in an adjacent hidden braneworld. We then describe how a low-background detector can detect neutrons arising from the hidden world and quantify the expected sensitivity to the swapping probability. As a proof of concept, a constraint is derived from previous experiments.

  18. Dynamic adjustment of hidden node parameters for extreme learning machine.

    PubMed

    Feng, Guorui; Lan, Yuan; Zhang, Xinpeng; Qian, Zhenxing

    2015-02-01

    Extreme learning machine (ELM), proposed by Huang et al., was developed for generalized single hidden layer feedforward networks with a wide variety of hidden nodes. ELMs have been proved very fast and effective especially for solving function approximation problems with a predetermined network structure. However, it may contain insignificant hidden nodes. In this paper, we propose dynamic adjustment ELM (DA-ELM) that can further tune the input parameters of insignificant hidden nodes in order to reduce the residual error. It is proved in this paper that the energy error can be effectively reduced by applying recursive expectation-minimization theorem. In DA-ELM, the input parameters of insignificant hidden node are updated in the decreasing direction of the energy error in each step. The detailed theoretical foundation of DA-ELM is presented in this paper. Experimental results show that the proposed DA-ELM is more efficient than the state-of-art algorithms such as Bayesian ELM, optimally-pruned ELM, two-stage ELM, Levenberg-Marquardt, sensitivity-based linear learning method as well as the preliminary ELM.

  19. Reputation and competition in a hidden action model.

    PubMed

    Fedele, Alessandro; Tedeschi, Piero

    2014-01-01

    The economics models of reputation and quality in markets can be classified in three categories. (i) Pure hidden action, where only one type of seller is present who can provide goods of different quality. (ii) Pure hidden information, where sellers of different types have no control over product quality. (iii) Mixed frameworks, which include both hidden action and hidden information. In this paper we develop a pure hidden action model of reputation and Bertrand competition, where consumers and firms interact repeatedly in a market with free entry. The price of the good produced by the firms is contractible, whilst the quality is noncontractible, hence it is promised by the firms when a contract is signed. Consumers infer future quality from all available information, i.e., both from what they know about past quality and from current prices. According to early contributions, competition should make reputation unable to induce the production of high-quality goods. We provide a simple solution to this problem by showing that high quality levels are sustained as an outcome of a stationary symmetric equilibrium.

  20. Infinite hidden conditional random fields for human behavior analysis.

    PubMed

    Bousmalis, Konstantinos; Zafeiriou, Stefanos; Morency, Louis-Philippe; Pantic, Maja

    2013-01-01

    Hidden conditional random fields (HCRFs) are discriminative latent variable models that have been shown to successfully learn the hidden structure of a given classification problem (provided an appropriate validation of the number of hidden states). In this brief, we present the infinite HCRF (iHCRF), which is a nonparametric model based on hierarchical Dirichlet processes and is capable of automatically learning the optimal number of hidden states for a classification task. We show how we learn the model hyperparameters with an effective Markov-chain Monte Carlo sampling technique, and we explain the process that underlines our iHCRF model with the Restaurant Franchise Rating Agencies analogy. We show that the iHCRF is able to converge to a correct number of represented hidden states, and outperforms the best finite HCRFs--chosen via cross-validation--for the difficult tasks of recognizing instances of agreement, disagreement, and pain. Moreover, the iHCRF manages to achieve this performance in significantly less total training, validation, and testing time.

  1. Reputation and Competition in a Hidden Action Model

    PubMed Central

    Fedele, Alessandro; Tedeschi, Piero

    2014-01-01

    The economics models of reputation and quality in markets can be classified in three categories. (i) Pure hidden action, where only one type of seller is present who can provide goods of different quality. (ii) Pure hidden information, where sellers of different types have no control over product quality. (iii) Mixed frameworks, which include both hidden action and hidden information. In this paper we develop a pure hidden action model of reputation and Bertrand competition, where consumers and firms interact repeatedly in a market with free entry. The price of the good produced by the firms is contractible, whilst the quality is noncontractible, hence it is promised by the firms when a contract is signed. Consumers infer future quality from all available information, i.e., both from what they know about past quality and from current prices. According to early contributions, competition should make reputation unable to induce the production of high-quality goods. We provide a simple solution to this problem by showing that high quality levels are sustained as an outcome of a stationary symmetric equilibrium. PMID:25329387

  2. Image segmentation using hidden Markov Gauss mixture models.

    PubMed

    Pyun, Kyungsuk; Lim, Johan; Won, Chee Sun; Gray, Robert M

    2007-07-01

    Image segmentation is an important tool in image processing and can serve as an efficient front end to sophisticated algorithms and thereby simplify subsequent processing. We develop a multiclass image segmentation method using hidden Markov Gauss mixture models (HMGMMs) and provide examples of segmentation of aerial images and textures. HMGMMs incorporate supervised learning, fitting the observation probability distribution given each class by a Gauss mixture estimated using vector quantization with a minimum discrimination information (MDI) distortion. We formulate the image segmentation problem using a maximum a posteriori criteria and find the hidden states that maximize the posterior density given the observation. We estimate both the hidden Markov parameter and hidden states using a stochastic expectation-maximization algorithm. Our results demonstrate that HMGMM provides better classification in terms of Bayes risk and spatial homogeneity of the classified objects than do several popular methods, including classification and regression trees, learning vector quantization, causal hidden Markov models (HMMs), and multiresolution HMMs. The computational load of HMGMM is similar to that of the causal HMM.

  3. Hidden Statistics Approach to Quantum Simulations

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2010-01-01

    Recent advances in quantum information theory have inspired an explosion of interest in new quantum algorithms for solving hard computational (quantum and non-quantum) problems. The basic principle of quantum computation is that the quantum properties can be used to represent structure data, and that quantum mechanisms can be devised and built to perform operations with this data. Three basic non-classical properties of quantum mechanics superposition, entanglement, and direct-product decomposability were main reasons for optimism about capabilities of quantum computers that promised simultaneous processing of large massifs of highly correlated data. Unfortunately, these advantages of quantum mechanics came with a high price. One major problem is keeping the components of the computer in a coherent state, as the slightest interaction with the external world would cause the system to decohere. That is why the hardware implementation of a quantum computer is still unsolved. The basic idea of this work is to create a new kind of dynamical system that would preserve the main three properties of quantum physics superposition, entanglement, and direct-product decomposability while allowing one to measure its state variables using classical methods. In other words, such a system would reinforce the advantages and minimize limitations of both quantum and classical aspects. Based upon a concept of hidden statistics, a new kind of dynamical system for simulation of Schroedinger equation is proposed. The system represents a modified Madelung version of Schroedinger equation. It preserves superposition, entanglement, and direct-product decomposability while allowing one to measure its state variables using classical methods. Such an optimal combination of characteristics is a perfect match for simulating quantum systems. The model includes a transitional component of quantum potential (that has been overlooked in previous treatment of the Madelung equation). The role of the

  4. A hidden efficacy of seemingly unproductive production

    NASA Astrophysics Data System (ADS)

    Kapur, Manu

    Contrary to the fairly established notion in the learning sciences that un-scaffolded, ill-structured problem-solving processes rarely lead to meaningful learning, this study reports a hidden efficacy of such processes in a synchronous, computer-supported, collaborative learning (CSCL) environment. A contrasting-case, double-transfer design investigated the effect of problem type (well- vs. ill-structured problems in Newtonian Kinematics) on collaborative processes and outcomes as well as the transfer of problem-solving skills to the individual. N = 104 triads of 11th-grade science students were randomly assigned to solve either well- or ill-structured problems. Thereafter, all participants individually solved well-structured problems followed by ill-structured problems. Findings suggested that compared to well-structured problem-solving groups, ill-structured problem-solving groups struggled with defining the problem and spent much of their sustained interactional effort around problem critiquing and solution evaluation within a discussion that was highly complex, chaotic, and divergent. As such, they found it difficult to converge on the causes of the problem, set appropriate criteria for a solution, and develop a solution, which, in turn, decreased their group performance. Thus, on many counts, production in ill-structured problem-solving groups seemed unproductive when compared to production in well-structured problem-solving groups. Notwithstanding, the contrasting-case, double-transfer design of this study provided participants in the ill-structured condition with an opportunity to spontaneously contrast the ill-structured problems that they had solved in groups with the well-structured problems they solved on an individual basis afterwards. This contrast helped them separate the relevant from the irrelevant components of ill-structured problems, thereby facilitating a spontaneous transfer of problem-solving skills, which, in the absence of the contrast

  5. Temperature compensation for miniaturized magnetic sector

    NASA Technical Reports Server (NTRS)

    Sinha, Mahadeva P. (Inventor)

    2002-01-01

    Temperature compensation for a magnetic sector used in mass spectrometry. A high temperature dependant magnetic sector is used. This magnetic sector is compensated by a magnetic shunt that has opposite temperature characteristics to those of the magnet.

  6. Hidden Figures Tour Kennedy Space Center Visitor Complex

    NASA Image and Video Library

    2016-12-12

    In the IMAX Theater of the Kennedy Space Center Visitor Complex Cast and crew members of the upcoming motion picture "Hidden Figures" participate in a question and answer session. From the left are Ted Melfi, writer and director of “Hidden Figures,” Octavia Spencer, who portrays Dorothy Vaughan in the film, Taraji P. Henson, who portrays Katherine Johnson, Pharrell Williams, musician and producer of “Hidden Figures," and Janelle Monáe, who portrays Mary Jackson. The movie is based on the book of the same title, by Margot Lee Shetterly. It chronicles the lives of Katherine Johnson, Dorothy Vaughan and Mary Jackson, three African-American women who worked for NASA as human "computers.” Their mathematical calculations were crucial to the success of Project Mercury missions including John Glenn’s orbital flight aboard Friendship 7 in 1962. The film is due in theaters in January 2017.

  7. Using the Hidden Curriculum to Teach Professionalism in Nursing Students

    PubMed Central

    Karimi, Zohreh; Ashktorab, Tahereh; Mohammadi, Easa; Abedi, Heidar Ali

    2014-01-01

    Background: Professionalism in nursing is critical for creating credibility and a positive image. Objectives: This study was carried out to explain the use of hidden curriculum in teaching professionalism in nursing students. Materials and Methods: This qualitative study was conducted through purposeful sampling strategy by the participation of 32 nursing students. The data were collected by using semi-structured interviews, and this process was continued until achieving data saturation and themes’ emergence. Content analysis method was used for data analysis. Results: Data analysis revealed three main themes: Development of understanding the professionalism elements, Variety of influenceability strategies, and Influenceability to various resources. Each theme consisted of some subthemes. Conclusions: The nursing students learnt the professionalism elements by different methods from different resources through the hidden curriculum. Therefore, exploration of the currently administered hidden curricula is suggested. PMID:24829784

  8. Using the hidden curriculum to teach professionalism in nursing students.

    PubMed

    Karimi, Zohreh; Ashktorab, Tahereh; Mohammadi, Easa; Abedi, Heidar Ali

    2014-03-01

    Professionalism in nursing is critical for creating credibility and a positive image. This study was carried out to explain the use of hidden curriculum in teaching professionalism in nursing students. This qualitative study was conducted through purposeful sampling strategy by the participation of 32 nursing students. The data were collected by using semi-structured interviews, and this process was continued until achieving data saturation and themes' emergence. Content analysis method was used for data analysis. DATA ANALYSIS REVEALED THREE MAIN THEMES: Development of understanding the professionalism elements, Variety of influenceability strategies, and Influenceability to various resources. Each theme consisted of some subthemes. The nursing students learnt the professionalism elements by different methods from different resources through the hidden curriculum. Therefore, exploration of the currently administered hidden curricula is suggested.

  9. Towards Exotic Hidden-Charm Pentaquarks in QCD.

    PubMed

    Chen, Hua-Xing; Chen, Wei; Liu, Xiang; Steele, T G; Zhu, Shi-Lin

    2015-10-23

    Inspired by P(c)(4380) and P(c)(4450) recently observed by LHCb, a QCD sum rule investigation is performed, by which they can be identified as exotic hidden-charm pentaquarks composed of an anticharmed meson and a charmed baryon. Our results suggest that P(c)(4380) and P(c)(4450) have quantum numbers J(P)=3/2(-) and 5/2(+), respectively. Furthermore, two extra hidden-charm pentaqurks with configurations D̅Σ(c)(*) and D̅(*)Σ(c)(*) are predicted, which have spin-parity quantum numbers J(P)=3/2(-) and J(P)=5/2(+), respectively. As an important extension, the mass predictions of hidden-bottom pentaquarks are also given. Searches for these partners of P(c)(4380) and P(c)(4450) are especially accessible at future experiments like LHCb and BelleII.

  10. Towards Exotic Hidden-Charm Pentaquarks in QCD

    NASA Astrophysics Data System (ADS)

    Chen, Hua-Xing; Chen, Wei; Liu, Xiang; Steele, T. G.; Zhu, Shi-Lin

    2015-10-01

    Inspired by Pc(4380 ) and Pc(4450 ) recently observed by LHCb, a QCD sum rule investigation is performed, by which they can be identified as exotic hidden-charm pentaquarks composed of an anticharmed meson and a charmed baryon. Our results suggest that Pc(4380 ) and Pc(4450 ) have quantum numbers JP=3 /2- and 5 /2+ , respectively. Furthermore, two extra hidden-charm pentaqurks with configurations D ¯Σc* and D¯*Σc* are predicted, which have spin-parity quantum numbers JP=3 /2- and JP=5 /2+, respectively. As an important extension, the mass predictions of hidden-bottom pentaquarks are also given. Searches for these partners of Pc(4380 ) and Pc(4450 ) are especially accessible at future experiments like LHCb and BelleII.

  11. The hidden ion population - Revisited. [in outer plasmasphere

    NASA Technical Reports Server (NTRS)

    Olsen, R. C.; Chappell, C. R.; Gallagher, D. L.; Green, J. L.; Gurnett, D. A.

    1985-01-01

    In an investigation conducted by Olsen (1982) on the basis of particle data taken with an electrostatic analyzer, it was found that a cold plasma population with a density between 10 and 100 per cu cm appeared suddenly when the satellite was eclipsed, but was hidden in sunlight. The present paper has the objective to show further measurements of ordinarily 'hidden' ion populations, in order to resolve some of the questions raised in connection with the Scatha satellite data reported by Olsen. It is found that the retarding ion mass spectrometer (RIMS) detector is capable of measuring the core of the plasma distribution in sunlight and eclipse, though the task is more easily done in eclipse. There are, however, limitations concerning the ability of the detector to measure all the plasma, all the time. It is, therefore, pointed out that continuous effective measurements of the 'hidden' ion population of the magnetosphere still awaits satellites with effective means of potential control.

  12. Detection and tracking of moving objects hidden from view

    NASA Astrophysics Data System (ADS)

    Gariepy, Genevieve; Tonolini, Francesco; Henderson, Robert; Leach, Jonathan; Faccio, Daniele

    2016-01-01

    The ability to detect motion and track a moving object hidden around a corner or behind a wall provides a crucial advantage when physically going around the obstacle is impossible or dangerous. Previous methods have demonstrated that it is possible to reconstruct the shape of an object hidden from view. However, these methods do not enable the tracking of movement in real time. We demonstrate a compact non-line-of-sight laser ranging technology that relies on the ability to send light around an obstacle using a scattering floor and then detect the return signal from a hidden object within only a few seconds of acquisition time. By detecting this signal with a single-photon avalanche diode (SPAD) camera, we follow the movement of an object located a metre away from the camera with centimetre precision. We discuss the possibility of applying this technology to a variety of real-life situations in the near future.

  13. TeraHertz imaging of hidden paint layers on canvas.

    PubMed

    Adam, Aurèle J L; Planken, Paul C M; Meloni, Sabrina; Dik, Joris

    2009-03-02

    We show terahertz reflection images of hidden paint layers in a painting on canvas and compare the results with X-ray Radiography and In-frared Reflectography. Our terahertz measurements show strong reflections from both the canvas/paint interface and from the raw umber/lead white interface, indicating sufficient refractive-index contrast. Our results show that X-rays cannot be used to image through the lead white pigment which effectively blocks the X-rays. Although Infrared Reflectography is capable of vaguely observing the hidden paint strokes from the canvas side, we show that only terahertz imaging is capable of providing information on the thickness of the hidden paint layers. Terahertz imaging is thus shown to be a powerful imaging method for art historians, conservators and conservation scientists.

  14. Multivariate longitudinal data analysis with mixed effects hidden Markov models.

    PubMed

    Raffa, Jesse D; Dubin, Joel A

    2015-09-01

    Multiple longitudinal responses are often collected as a means to capture relevant features of the true outcome of interest, which is often hidden and not directly measurable. We outline an approach which models these multivariate longitudinal responses as generated from a hidden disease process. We propose a class of models which uses a hidden Markov model with separate but correlated random effects between multiple longitudinal responses. This approach was motivated by a smoking cessation clinical trial, where a bivariate longitudinal response involving both a continuous and a binomial response was collected for each participant to monitor smoking behavior. A Bayesian method using Markov chain Monte Carlo is used. Comparison of separate univariate response models to the bivariate response models was undertaken. Our methods are demonstrated on the smoking cessation clinical trial dataset, and properties of our approach are examined through extensive simulation studies.

  15. Applications of hidden symmetries to black hole physics

    NASA Astrophysics Data System (ADS)

    Frolov, Valeri

    2011-02-01

    This work is a brief review of applications of hidden symmetries to black hole physics. Symmetry is one of the most important concepts of the science. In physics and mathematics the symmetry allows one to simplify a problem, and often to make it solvable. According to the Noether theorem symmetries are responsible for conservation laws. Besides evident (explicit) spacetime symmetries, responsible for conservation of energy, momentum, and angular momentum of a system, there also exist what is called hidden symmetries, which are connected with higher order in momentum integrals of motion. A remarkable fact is that black holes in four and higher dimensions always possess a set ('tower') of explicit and hidden symmetries which make the equations of motion of particles and light completely integrable. The paper gives a general review of the recently obtained results. The main focus is on understanding why at all black holes have something (symmetry) to hide.

  16. A fast hidden line algorithm for plotting finite element models

    NASA Technical Reports Server (NTRS)

    Jones, G. K.

    1982-01-01

    Effective plotting of finite element models requires the use of fast hidden line plot techniques that provide interactive response. A high speed hidden line technique was developed to facilitate the plotting of NASTRAN finite element models. Based on testing using 14 different models, the new hidden line algorithm (JONES-D) appears to be very fast: its speed equals that for normal (all lines visible) plotting and when compared to other existing methods it appears to be substantially faster. It also appears to be very reliable: no plot errors were observed using the new method to plot NASTRAN models. The new algorithm was made part of the NPLOT NASTRAN plot package and was used by structural analysts for normal production tasks.

  17. Hidden Area and Mechanical Nonlinearities in Freestanding Graphene.

    PubMed

    Nicholl, Ryan J T; Lavrik, Nickolay V; Vlassiouk, Ivan; Srijanto, Bernadeta R; Bolotin, Kirill I

    2017-06-30

    We investigated the effect of out-of-plane crumpling on the mechanical response of graphene membranes. In our experiments, stress was applied to graphene membranes using pressurized gas while the strain state was monitored through two complementary techniques: interferometric profilometry and Raman spectroscopy. By comparing the data obtained through these two techniques, we determined the geometric hidden area which quantifies the crumpling strength. While the devices with hidden area ∼0% obeyed linear mechanics with biaxial stiffness 428±10  N/m, specimens with hidden area in the range 0.5%-1.0% were found to obey an anomalous nonlinear Hooke's law with an exponent ∼0.1.

  18. Ultrafast scanning probe microscopy

    DOEpatents

    Weiss, Shimon; Chemla, Daniel S.; Ogletree, D. Frank; Botkin, David

    1995-01-01

    An ultrafast scanning probe microscopy method for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample.

  19. Traversing probe system

    DOEpatents

    Mashburn, Douglas N.; Stevens, Richard H.; Woodall, Harold C.

    1977-01-01

    This invention comprises a rotatable annular probe-positioner which carries at least one radially disposed sensing probe, such as a Pitot tube having a right-angled tip. The positioner can be coaxially and rotatably mounted within a compressor casing or the like and then actuated to orient the sensing probe as required to make measurements at selected stations in the annulus between the positioner and compressor casing. The positioner can be actuated to (a) selectively move the probe along its own axis, (b) adjust the yaw angle of the right-angled probe tip, and (c) revolve the probe about the axis common to the positioner and casing. A cam plate engages a cam-follower portion of the probe and normally rotates with the positioner. The positioner includes a first-motor-driven ring gear which effects slidable movement of the probe by rotating the positioner at a time when an external pneumatic cylinder is actuated to engage the cam plate and hold it stationary. When the pneumatic cylinder is not actuated, this ring gear can be driven to revolve the positioner and thus the probe to a desired circumferential location about the above-mentioned common axis. A second motor-driven ring gear included in the positioner can be driven to rotate the probe about its axis, thus adjusting the yaw angle of the probe tip. The positioner can be used in highly corrosive atmosphere, such as gaseous uranium hexafluoride.

  20. Ultrafast scanning probe microscopy

    DOEpatents

    Weiss, S.; Chemla, D.S.; Ogletree, D.F.; Botkin, D.

    1995-05-16

    An ultrafast scanning probe microscopy method is described for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample. 6 Figs.

  1. Dry Cleaning Sector (NAICS 8123)

    EPA Pesticide Factsheets

    The dry cleaning sector includes establishments engaged in providing laundry services and industrial launderers. Find environmental regulatory information for perchloroethylene (PERC) cleaners as well as hazardous waste regulations for dry cleaners.

  2. Textile Manufacturing Sector (NAICS 313)

    EPA Pesticide Factsheets

    Find environmental regulatory and compliance information for the textile and leather manufacturing sector, including NESHAPs for leather tanning and fabric printing, and small business guidance for RCRA hazardous waste requirements.

  3. Wood and Paper Manufacturing Sectors

    EPA Pesticide Factsheets

    Find EPA regulatory information for the wood product and paper manufacturing sectors, including paper, pulp and lumber. Information includes NESHAPs and effluent guidelines for pulp and paper rulemaking, and compliance guidelines

  4. Chemical Manufacturing Sector (NAICS 325)

    EPA Pesticide Factsheets

    find EPA regulatory information for the chemical manufacturing sector, including NESHAPs, the SNAP program for ozone depleting substances,effluent guidelines, and new and existing chemicals testing requirements under TSCA.

  5. Electrical resistivity probes

    DOEpatents

    Lee, Ki Ha; Becker, Alex; Faybishenko, Boris A.; Solbau, Ray D.

    2003-10-21

    A miniaturized electrical resistivity (ER) probe based on a known current-voltage (I-V) electrode structure, the Wenner array, is designed for local (point) measurement. A pair of voltage measuring electrodes are positioned between a pair of current carrying electrodes. The electrodes are typically about 1 cm long, separated by 1 cm, so the probe is only about 1 inch long. The electrodes are mounted to a rigid tube with electrical wires in the tube and a sand bag may be placed around the electrodes to protect the electrodes. The probes can be positioned in a borehole or on the surface. The electrodes make contact with the surrounding medium. In a dual mode system, individual probes of a plurality of spaced probes can be used to measure local resistance, i.e. point measurements, but the system can select different probes to make interval measurements between probes and between boreholes.

  6. Detect and exploit hidden structure in fatty acid signature data

    USGS Publications Warehouse

    Budge, Suzanne; Bromaghin, Jeffrey; Thiemann, Gregory

    2017-01-01

    Estimates of predator diet composition are essential to our understanding of their ecology. Although several methods of estimating diet are practiced, methods based on biomarkers have become increasingly common. Quantitative fatty acid signature analysis (QFASA) is a popular method that continues to be refined and extended. Quantitative fatty acid signature analysis is based on differences in the signatures of prey types, often species, which are recognized and designated by investigators. Similarly, predator signatures may be structured by known factors such as sex or age class, and the season or region of sample collection. The recognized structure in signature data inherently influences QFASA results in important and typically beneficial ways. However, predator and prey signatures may contain additional, hidden structure that investigators either choose not to incorporate into an analysis or of which they are unaware, being caused by unknown ecological mechanisms. Hidden structure also influences QFASA results, most often negatively. We developed a new method to explore signature data for hidden structure, called divisive magnetic clustering (DIMAC). Our DIMAC approach is based on the same distance measure used in diet estimation, closely linking methods of data exploration and parameter estimation, and it does not require data transformation or distributional assumptions, as do many multivariate ordination methods in common use. We investigated the potential benefits of the DIMAC method to detect and subsequently exploit hidden structure in signature data using two prey signature libraries with quite different characteristics. We found that the existence of hidden structure in prey signatures can increase the confusion between prey types and thereby reduce the accuracy and precision of QFASA diet estimates. Conversely, the detection and exploitation of hidden structure represent a potential opportunity to improve predator diet estimates and may lead to new

  7. Analysing the hidden curriculum: use of a cultural web

    PubMed Central

    Mossop, Liz; Dennick, Reg; Hammond, Richard; Robbé, Iain

    2013-01-01

    CONTEXT Major influences on learning about medical professionalism come from the hidden curriculum. These influences can contribute positively or negatively towards the professional enculturation of clinical students. The fact that there is no validated method for identifying the components of the hidden curriculum poses problems for educators considering professionalism. The aim of this study was to analyse whether a cultural web, adapted from a business context, might assist in the identification of elements of the hidden curriculum at a UK veterinary school. METHODS A qualitative approach was used. Seven focus groups consisting of three staff groups and four student groups were organised. Questioning was framed using the cultural web, which is a model used by business owners to assess their environment and consider how it affects their employees and customers. The focus group discussions were recorded, transcribed and analysed thematically using a combination of a priori and emergent themes. RESULTS The cultural web identified elements of the hidden curriculum for both students and staff. These included: core assumptions; routines; rituals; control systems; organisational factors; power structures, and symbols. Discussions occurred about how and where these issues may affect students’ professional identity development. CONCLUSIONS The cultural web framework functioned well to help participants identify elements of the hidden curriculum. These aspects aligned broadly with previously described factors such as role models and institutional slang. The influence of these issues on a student’s development of a professional identity requires discussion amongst faculty staff, and could be used to develop learning opportunities for students. The framework is promising for the analysis of the hidden curriculum and could be developed as an instrument for implementation in other clinical teaching environments. PMID:23323652

  8. Hidden SU(N) glueball dark matter

    SciTech Connect

    Soni, Amarjit; Zhang, Yue

    2016-06-21

    Here we investigate the possibility that the dark matter candidate is from a pure non-abelian gauge theory of the hidden sector, motivated in large part by its elegance and simplicity. The dark matter is the lightest bound state made of the confined gauge fields, the hidden glueball. We point out this simple setup is capable of providing rich and novel phenomena in the dark sector, especially in the parameter space of large N. They include self-interacting and warm dark matter scenarios, Bose-Einstein condensation leading to massive dark stars possibly millions of times heavier than our sun giving rise to gravitational lensing effects, and indirect detections through higher dimensional operators as well as interesting collider signatures.

  9. Hidden SU(N) glueball dark matter

    SciTech Connect

    Soni, Amarjit; Zhang, Yue

    2016-06-21

    Here we investigate the possibility that the dark matter candidate is from a pure non-abelian gauge theory of the hidden sector, motivated in large part by its elegance and simplicity. The dark matter is the lightest bound state made of the confined gauge fields, the hidden glueball. We point out this simple setup is capable of providing rich and novel phenomena in the dark sector, especially in the parameter space of large N. They include self-interacting and warm dark matter scenarios, Bose-Einstein condensation leading to massive dark stars possibly millions of times heavier than our sun giving rise to gravitational lensing effects, and indirect detections through higher dimensional operators as well as interesting collider signatures.

  10. The INTEGRAL/SPI 511 keV Signal from Hidden Valleys

    SciTech Connect

    Davoudiasl, H.; Perez, G.

    2009-12-01

    We examine under what circumstances the INTEGRAL/SPI 511 keV signal can originate from decays of MeV-scale composite states produced by: (A) thermonuclear (type Ia) or (B) core collapse supernovae (SNe). The requisite dynamical properties that would account for the observed data are quite distinct, for cases (A) and (B). We determine these requirements in simple hidden valley models, where the escape fraction problem is naturally addressed, due to the long lifetime of the new composite states. A novel feature of scenario (A) is that the dynamics of type Ia SNe, standard candles for cosmological measurements, might be affected by our mechanism. In case (A), the mass of the state mediating between the hidden sector and the SM e{sup +}e{sup -} could be a few hundred GeV and within the reach of a 500GeV e{sup +}e{sup -} linear collider. We also note that kinetic mixing of the photon with a light vector state may provide an interesting alternate mediation mechanism in this case. Scenarios based on case (B) are challenged by the need for a mechanism to transport some of the produced positrons toward the Galactic bulge, due to the inferred distribution of core collapse sources. The mass of the mediator in case (B) is typically hundreds of TeV, leading to long-lived particles that could, under certain circumstances, include a viable dark matter candidate. The appearance of long-lived particles in typical models leads to cosmological constraints and we address how a consistent cosmic history may be achieved.

  11. Application of Hidden Markov Models in Biomolecular Simulations.

    PubMed

    Shukla, Saurabh; Shamsi, Zahra; Moffett, Alexander S; Selvam, Balaji; Shukla, Diwakar

    2017-01-01

    Hidden Markov models (HMMs) provide a framework to analyze large trajectories of biomolecular simulation datasets. HMMs decompose the conformational space of a biological molecule into finite number of states that interconvert among each other with certain rates. HMMs simplify long timescale trajectories for human comprehension, and allow comparison of simulations with experimental data. In this chapter, we provide an overview of building HMMs for analyzing bimolecular simulation datasets. We demonstrate the procedure for building a Hidden Markov model for Met-enkephalin peptide simulation dataset and compare the timescales of the process.

  12. On Noncontextual, Non-Kolmogorovian Hidden Variable Theories

    NASA Astrophysics Data System (ADS)

    Feintzeig, Benjamin H.; Fletcher, Samuel C.

    2017-01-01

    One implication of Bell's theorem is that there cannot in general be hidden variable models for quantum mechanics that both are noncontextual and retain the structure of a classical probability space. Thus, some hidden variable programs aim to retain noncontextuality at the cost of using a generalization of the Kolmogorov probability axioms. We generalize a theorem of Feintzeig (Br J Philos Sci 66(4): 905-927, 2015) to show that such programs are committed to the existence of a finite null cover for some quantum mechanical experiments, i.e., a finite collection of probability zero events whose disjunction exhausts the space of experimental possibilities.

  13. A classical theory of continuous spin and hidden gauge invariance

    SciTech Connect

    Zoller, D.

    1991-12-31

    We present a classical higher derivative point particle theory whose quantization gives Wigner`s continuous spin representation of the Poincare group. Although the theory is not reparameterization invariant in the usual sense, it does possess a hidden gauge invariance that provides a non-local representation of the reparameterization group. The Hamiltonian of the theory does not vanish and its value is the continuous spin parameter. The theory presented here represents the simplest example of a wide class of higher derivative theories possessing a hidden gauge invariance.

  14. A classical theory of continuous spin and hidden gauge invariance

    SciTech Connect

    Zoller, D.

    1991-01-01

    We present a classical higher derivative point particle theory whose quantization gives Wigner's continuous spin representation of the Poincare group. Although the theory is not reparameterization invariant in the usual sense, it does possess a hidden gauge invariance that provides a non-local representation of the reparameterization group. The Hamiltonian of the theory does not vanish and its value is the continuous spin parameter. The theory presented here represents the simplest example of a wide class of higher derivative theories possessing a hidden gauge invariance.

  15. On Noncontextual, Non-Kolmogorovian Hidden Variable Theories

    NASA Astrophysics Data System (ADS)

    Feintzeig, Benjamin H.; Fletcher, Samuel C.

    2017-02-01

    One implication of Bell's theorem is that there cannot in general be hidden variable models for quantum mechanics that both are noncontextual and retain the structure of a classical probability space. Thus, some hidden variable programs aim to retain noncontextuality at the cost of using a generalization of the Kolmogorov probability axioms. We generalize a theorem of Feintzeig (Br J Philos Sci 66(4): 905-927, 2015) to show that such programs are committed to the existence of a finite null cover for some quantum mechanical experiments, i.e., a finite collection of probability zero events whose disjunction exhausts the space of experimental possibilities.

  16. The hidden opportunity cost of time effect on intertemporal choice

    PubMed Central

    Zhao, Cui-Xia; Jiang, Cheng-Ming; Zhou, Lei; Li, Shu; Rao, Li-Lin; Zheng, Rui

    2015-01-01

    An interesting phenomenon called “hidden opportunity cost of time effect” was detected in intertemporal choices. The majority of our participants preferred the smaller but sooner (SS) option to the larger but later (LL) option if opportunity cost was explicit. However, a higher proportion of participants preferred the LL to SS option if opportunity cost was hidden. This shift violates the invariance principle and opens a new way to encourage future-oriented behavior. By simply mentioning the “obvious” opportunity cost of alternatives, decision makers can be more informed in prioritizing their long-term goals rather than short-term goals. PMID:25870570

  17. Probing anomalous Higgs couplings in H → ZV decays

    NASA Astrophysics Data System (ADS)

    Modak, Tanmoy; Srivastava, Rahul

    2017-01-01

    We analyze the possibility of probing anomalous Higgs couplings in the rare decays H → ZV, V being a vector quarkonium state. These rare decays involve both gauge as well as the Yukawa sectors and either of them can potentially be anomalous. We show that the branching fractions for H → ZV decays in Standard Model (SM) are small, making it a sensitive probe for anomalous Higgs couplings originating from physics beyond SM. Moreover, as both V and Z can decay into pair of charged leptons, they provide experimentally clean channels and future LHC runs should observe such decays. We perform a model independent analysis and show how angular asymmetries can be used to probe these anomalous Higgs couplings, taking further decays of V and Z to pair of charged leptons into account. The angular asymmetries can provide significant information about anomalous Higgs couplings in both gauge and Yukawa sectors.

  18. Dark sectors of the Universe: A Euclid survey approach

    NASA Astrophysics Data System (ADS)

    Tutusaus, Isaac; Lamine, Brahim; Blanchard, Alain; Dupays, Arnaud; Rousset, Yvan; Zolnierowski, Yves

    2016-12-01

    In this paper we study the consequences of relaxing the hypothesis of the pressureless nature of the dark matter component when determining constraints on dark energy. To this aim we consider simple generalized dark matter models with constant equation of state parameter. We find that present-day low-redshift probes (type-Ia supernovae and baryonic acoustic oscillations) lead to a complete degeneracy between the dark energy and the dark matter sectors. However, adding the cosmic microwave background (CMB) high-redshift probe restores constraints similar to those on the standard Λ CDM model. We then examine the anticipated constraints from the future Euclid survey on the same class of models, using a Fisher forecast estimation. We show that the Euclid survey allows us to break the degeneracy between the dark sectors, although the constraints on dark energy are much weaker than with standard dark matter. The use of CMB in combination allows us to restore the high precision on the dark energy sector constraints.

  19. 78 FR 17744 - Culturally Significant Objects Imported for Exhibition Determinations: “Maya: Hidden Worlds...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``Maya: Hidden Worlds Revealed... determine that the objects to be included in the exhibition ``Maya: Hidden Worlds Revealed,'' imported from...

  20. Short Summary European Reports on Retail Sector, Motor Vehicle Repair and Sales Sector, Food and Beverages Sector.

    ERIC Educational Resources Information Center

    European Centre for the Development of Vocational Training, Berlin (Germany).

    This document is composed of European synthesis reports on retail trade, the agro-food sector, and the motor vehicle sales and repair sector. They are based on the most important findings of the European report and the 12 national reports for each sector. Section 1, "Retail Sector," deals in part 1 with the structure of retailing in the…

  1. High temperature probe

    DOEpatents

    Swan, Raymond A.

    1994-01-01

    A high temperature probe for sampling, for example, smokestack fumes, and is able to withstand temperatures of 3000.degree. F. The probe is constructed so as to prevent leakage via the seal by placing the seal inside the water jacket whereby the seal is not exposed to high temperature, which destroys the seal. The sample inlet of the probe is also provided with cooling fins about the area of the seal to provide additional cooling to prevent the seal from being destroyed. Also, a heated jacket is provided for maintaining the temperature of the gas being tested as it passes through the probe. The probe includes pressure sensing means for determining the flow velocity of an efficient being sampled. In addition, thermocouples are located in various places on the probe to monitor the temperature of the gas passing there through.

  2. Neuro fuzzy force control for soft dry contact Hertzian ultrasonic probe

    NASA Astrophysics Data System (ADS)

    Gallegos, E.; Baltazar, A.; Treesatayapun, C.

    2016-02-01

    In this work the use of a cartesian robotic manipulator as scanner for the automated identification of hidden defects in an aluminum test plate is proposed. The robotic manipulator includes a custom made soft deformable ultrasonic probe and a force sensor for the recollection of the ultrasonic signals and force feedback. The contact between the soft probe and the test plate is regulated using a Neuro Fuzzy controller in order to avoid the complex mathematical model produced by the interaction. Finally the use of the correlation coefficient is proposed for the post processing of the obtained ultrasonic signals and identification of hidden defects inside the test plate. Experimental studies demonstrated the efficiency of the method.

  3. An Approach for Detecting Malicious Emails Using Runtime Monitoring with Hidden Data

    DTIC Science & Technology

    2016-09-01

    WITH HIDDEN DATA .......................21 A. ARCHITECTURE ...................................................................................21 B... Architecture for Malicious Emails. Source: [21]. ........ 21 Figure 10. Workflow for Developing Pattern Matching with Hidden Information. Source...WITH HIDDEN DATA A. ARCHITECTURE In Chapter III, we overviewed deterministic RM. In this chapter we introduce a recent architecture that enables RM

  4. The Relationship Between Chaotic Maps and Some Chaotic Systems with Hidden Attractors

    NASA Astrophysics Data System (ADS)

    Jafari, Sajad; Pham, Viet-Thanh; Golpayegani, S. Mohammad Reza Hashemi; Moghtadaei, Motahareh; Kingni, Sifeu Takougang

    2016-12-01

    In this note, hidden attractors in chaotic maps are investigated. Although there are many new researches on hidden attractors in chaotic flows, no investigation has been done on hidden attractors in maps based on our knowledge. In addition, a new interesting chaotic map with a bifurcation diagram starting from any desired period and then continuing with period doubling is introduced in this paper.

  5. Multipressure and Temperature Probe

    NASA Technical Reports Server (NTRS)

    Raman, K. R.

    1982-01-01

    Aerodynamic probe is a small cylinder tube holding a network of tiny tubes leading to various ports. Six parameters are recorded simultaneously with little interference with aerodynamic flow. Two tubes connected by a hot-wire tungsten probe sense steady and fluctuating components of total and static pressures; the feedbacks from these tubes are input into differential-pressure sensors to measure fluctuating components of the pressures. Data are recorded by instruments at the back end of the probe.

  6. Cultural Reproduction Via the Hidden Curriculum. Working Draft.

    ERIC Educational Resources Information Center

    Hannay, Lynne M.

    This examination of the reproduction of cultural norms focuses on ways in which the hidden curriculum facilitates cultural reproduction. The conceptual framework outlined in this paper emerged from a five-month observation study of a tenth-grade social studies class located in a predominantly working-class school. During the on-going data…

  7. 29. WORTHINGTON FIRE PUMP WITH TURBINE HIDDEN BEHIND. PUMP HOUSE ...

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

    29. WORTHINGTON FIRE PUMP WITH TURBINE HIDDEN BEHIND. PUMP HOUSE IS LOCATED AT HEAD OF OLD TRASH GATES. PUMP ENTERS WATER ON EXTERIOR OF WALL IN FAR SIDE OF PHOTO. - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

  8. Doing School Time: The Hidden Curriculum Goes to Prison

    ERIC Educational Resources Information Center

    García, José; De Lissovoy, Noah

    2013-01-01

    The hidden curriculum is generally understood as the process by which daily exposure to school expectations and routines transmits norms and values of the dominant society to students. In the present, through the regimentation of thought, control of bodies and movement, and proliferation of punishment, contemporary accountability and testing…

  9. Local clustering in scale-free networks with hidden variables

    NASA Astrophysics Data System (ADS)

    van der Hofstad, Remco; Janssen, A. J. E. M.; van Leeuwaarden, Johan S. H.; Stegehuis, Clara

    2017-02-01

    We investigate the presence of triangles in a class of correlated random graphs in which hidden variables determine the pairwise connections between vertices. The class rules out self-loops and multiple edges. We focus on the regime where the hidden variables follow a power law with exponent τ ∈(2 ,3 ) , so that the degrees have infinite variance. The natural cutoff hc characterizes the largest degrees in the hidden variable models, and a structural cutoff hs introduces negative degree correlations (disassortative mixing) due to the infinite-variance degrees. We show that local clustering decreases with the hidden variable (or degree). We also determine how the average clustering coefficient C scales with the network size N , as a function of hs and hc. For scale-free networks with exponent 2 <τ <3 and the default choices hs˜N1 /2 and hc˜N1 /(τ -1 ) this gives C ˜N2 -τlnN for the universality class at hand. We characterize the extremely slow decay of C when τ ≈2 and show that for τ =2.1 , say, clustering starts to vanish only for networks as large as N =109 .

  10. Education as Text: The Varieties of Educational Hiddenness.

    ERIC Educational Resources Information Center

    Gordon, David

    1988-01-01

    Using the ideas of Paul Ricoeur and Clifford Geertz, this article develops the notion of education as a "text" and analyzes the "hidden curriculum" of that text as it is read by all members of the society. The hypothesis is proposed that education becomes a text about society's myths and sacred beliefs. (TE)

  11. Quantile regression reveals hidden bias and uncertainty in habitat models

    Treesearch

    Brian S. Cade; Barry R. Noon; Curtis H. Flather

    2005-01-01

    We simulated the effects of missing information on statistical distributions of animal response that covaried with measured predictors of habitat to evaluate the utility and performance of quantile regression for providing more useful intervals of uncertainty in habitat relationships. These procedures were evaulated for conditions in which heterogeneity and hidden bias...

  12. The Hidden Costs of Outdoor Education/Recreation Academic Training.

    ERIC Educational Resources Information Center

    Bisson, Christian

    Academic training programs in the field of outdoor education and recreation have increased considerably in the past few decades, but their true costs are often hidden. A survey of 15 outdoor college programs in the United States and Canada examined special fees associated with outdoor courses. The cost of necessary personal equipment and clothing…

  13. Hidden, Unacknowledged, Acquaintance, and Date Rape: Looking Back, Looking Forward

    ERIC Educational Resources Information Center

    Koss, Mary P.

    2011-01-01

    In this commentary, the author reflects on two articles that have been among the most highly cited publications in "Psychology of Women Quarterly" ("PWQ") over its first 35 years, "The Hidden Rape Victim: Personality, Attitudinal, and Situational Characteristics" (Koss, 1985) and "Stranger and Acquaintance Rape: Are There Differences in the…

  14. Simple yet Hidden Counterexamples in Undergraduate Real Analysis

    ERIC Educational Resources Information Center

    Shipman, Barbara A.; Shipman, Patrick D.

    2013-01-01

    We study situations in introductory analysis in which students affirmed false statements as true, despite simple counterexamples that they easily recognized afterwards. The study draws attention to how simple counterexamples can become hidden in plain sight, even in an active learning atmosphere where students proposed simple (as well as more…

  15. Thermoelectric generator hidden in a shirt with a fabric radiator

    NASA Astrophysics Data System (ADS)

    Leonov, Vladimir; Vullers, Ruud J. M.; Hoof, Chris Van

    2012-06-01

    Integration of thermopiles in garments has been performed in this work in different ways. It is shown that textile has a minor effect on power generation, which enables completely hidden and unobtrusive energy harvester. A one-milliwatt thermoelectric generator is then integrated between two layers of a shirt and its characteristics are reported.

  16. The College Completion Puzzle: A Hidden Markov Model Approach

    ERIC Educational Resources Information Center

    Witteveen, Dirk; Attewell, Paul

    2017-01-01

    Higher education in America is characterized by widespread access to college but low rates of completion, especially among undergraduates at less selective institutions. We analyze longitudinal transcript data to examine processes leading to graduation, using Hidden Markov modeling. We identify several latent states that are associated with…

  17. On local-hidden-variable no-go theorems

    NASA Astrophysics Data System (ADS)

    Methot, A. A.

    2006-06-01

    The strongest attack against quantum mechanics came in 1935 in the form of a paper by Einstein, Podolsky, and Rosen. It was argued that the theory of quantum mechanics could not be called a complete theory of Nature, for every element of reality is not represented in the formalism as such. The authors then put forth a proposition: we must search for a theory where, upon knowing everything about the system, including possible hidden variables, one could make precise predictions concerning elements of reality. This project was ultimately doomed in 1964 with the work of Bell, who showed that the most general local hidden variable theory could not reproduce correlations that arise in quantum mechanics. There exist mainly three forms of no-go theorems for local hidden variable theories. Although almost every physicist knows the consequences of these no-go theorems, not every physicist is aware of the distinctions between the three or even their exact definitions. Thus, we will discuss here the three principal forms of no-go theorems for local hidden variable theories of Nature. We will define Bell theorems, Bell theorems without inequalities, and pseudo-telepathy. A discussion of the similarities and differences will follow.

  18. Unpacking the Hidden Efficacies of Learning in Productive Failure

    ERIC Educational Resources Information Center

    Hung, David; Chen, Victor; Lim, Seo Hong

    2009-01-01

    This paper describes a framework for learning where learners undergo experimentations with the phenomena at hand according to progressive and staged goals. Bowling is used as a case study in this paper. The premise for experimentations is that learners can experience hidden efficacies, including the formation of "bad habits." A distinction is made…

  19. Hidden Item Variance in Multiple Mini-Interview Scores

    ERIC Educational Resources Information Center

    Zaidi, Nikki L.; Swoboda, Christopher M.; Kelcey, Benjamin M.; Manuel, R. Stephen

    2017-01-01

    The extant literature has largely ignored a potentially significant source of variance in multiple mini-interview (MMI) scores by "hiding" the variance attributable to the sample of attributes used on an evaluation form. This potential source of hidden variance can be defined as rating items, which typically comprise an MMI evaluation…

  20. Commitment-Based Learning of Hidden Linguistic Structures

    ERIC Educational Resources Information Center

    Akers, Crystal Gayle

    2012-01-01

    Learners must simultaneously learn a grammar and a lexicon from observed forms, yet some structures that the grammar and lexicon reference are unobservable in the acoustic signal. Moreover, these "hidden" structures interact: the grammar maps an underlying form to a particular interpretation. Learning one structure depends on learning…

  1. A coupled hidden Markov model for disease interactions

    PubMed Central

    Sherlock, Chris; Xifara, Tatiana; Telfer, Sandra; Begon, Mike

    2013-01-01

    To investigate interactions between parasite species in a host, a population of field voles was studied longitudinally, with presence or absence of six different parasites measured repeatedly. Although trapping sessions were regular, a different set of voles was caught at each session, leading to incomplete profiles for all subjects. We use a discrete time hidden Markov model for each disease with transition probabilities dependent on covariates via a set of logistic regressions. For each disease the hidden states for each of the other diseases at a given time point form part of the covariate set for the Markov transition probabilities from that time point. This allows us to gauge the influence of each parasite species on the transition probabilities for each of the other parasite species. Inference is performed via a Gibbs sampler, which cycles through each of the diseases, first using an adaptive Metropolis–Hastings step to sample from the conditional posterior of the covariate parameters for that particular disease given the hidden states for all other diseases and then sampling from the hidden states for that disease given the parameters. We find evidence for interactions between several pairs of parasites and of an acquired immune response for two of the parasites. PMID:24223436

  2. A coupled hidden Markov model for disease interactions.

    PubMed

    Sherlock, Chris; Xifara, Tatiana; Telfer, Sandra; Begon, Mike

    2013-08-01

    To investigate interactions between parasite species in a host, a population of field voles was studied longitudinally, with presence or absence of six different parasites measured repeatedly. Although trapping sessions were regular, a different set of voles was caught at each session, leading to incomplete profiles for all subjects. We use a discrete time hidden Markov model for each disease with transition probabilities dependent on covariates via a set of logistic regressions. For each disease the hidden states for each of the other diseases at a given time point form part of the covariate set for the Markov transition probabilities from that time point. This allows us to gauge the influence of each parasite species on the transition probabilities for each of the other parasite species. Inference is performed via a Gibbs sampler, which cycles through each of the diseases, first using an adaptive Metropolis-Hastings step to sample from the conditional posterior of the covariate parameters for that particular disease given the hidden states for all other diseases and then sampling from the hidden states for that disease given the parameters. We find evidence for interactions between several pairs of parasites and of an acquired immune response for two of the parasites.

  3. Resources of learning through hidden curriculum: Iranian nursing students’ perspective

    PubMed Central

    Karimi, Zohreh; Ashktorab, Tahereh; Mohammadi, Eesa; Abedi, Heidarali; Zarea, Kourosh

    2015-01-01

    Background: Students tend to internalize and perpetuate the patterns of behavior and the values surrounding them. Review of literature showed that there are several student learning sources through the hidden curriculum, but they have not been identified in nursing yet. Hence, the purpose of this study is explanation of learning resources in the hidden curriculum in the view of baccalaureate nursing students. Materials and Methods: This qualitative study was carried out in 2012 with the participation of 32 baccalaureate nursing students in Nursing and Midwifery College of Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran by purposeful sampling strategies. Data were collected by semi-structured interviews and continued to the level of data saturation and themes’ emergence. Data analysis was performed through inductive content analysis method. Result: “Instructor as the unique learning element,” “various learning resources in the clinical setting,” and “instructive nature of the education environment” were extracted as the main themes, each of which incorporated some categories. Conclusion: Baccalaureate undergraduate nursing students learnt the hidden curriculum by the resources such as instructors, resources existing in the clinical setting, and the university campus. Therefore, more research is recommended for the identification of other resources. In order to promote positive messages and reduce the negative messages of the hidden curricula running at academic and clinical settings, nursing educators and nurses need to learn more about this issue in the nursing profession. PMID:26430684

  4. Progressing to University: Hidden Messages at Two State Schools

    ERIC Educational Resources Information Center

    Donnelly, Michael

    2015-01-01

    This paper considers some of the ways that schools play a role in shaping higher education (HE) decision-making. Through their everyday practices and processes, schools can carry hidden messages about progression to HE, including choice of university. The sorts of routine aspects of school life dealt with here include events and activities,…

  5. Doing School Time: The Hidden Curriculum Goes to Prison

    ERIC Educational Resources Information Center

    García, José; De Lissovoy, Noah

    2013-01-01

    The hidden curriculum is generally understood as the process by which daily exposure to school expectations and routines transmits norms and values of the dominant society to students. In the present, through the regimentation of thought, control of bodies and movement, and proliferation of punishment, contemporary accountability and testing…

  6. Hidden algebra method (quasi-exact-solvability in quantum mechanics)

    SciTech Connect

    Turbiner, Alexander

    1996-02-20

    A general introduction to quasi-exactly-solvable problems of quantum mechanics is presented. Main attention is given to multidimensional quasi-exactly-solvable and exactly-solvable Schroedinger operators. Exact-solvability of the Calogero and Sutherland N-body problems ass ociated with an existence of the hidden algebra slN is discussed extensively.

  7. Mapping hidden wall structures by quantitative IR thermography

    NASA Astrophysics Data System (ADS)

    Rosina, Elisabetta; Grinzato, Ermanno G.; Robison, Elwin C.

    2002-03-01

    Knowledge of an historic monument can be substantially improved by locating hidden structures, openings and the wall bonding beneath the plaster. When restoring buildings, the physical connection between the walls must be known in order to predict the risk areas for structural weakness. IR Thermography produces remarkable results, especially by means of the quantitative approach. The temperature pattern detected by thermography and analyzed in space and time maps the hidden structure of the wall. Thick walls exposed to the weather represent a challenge in detecting hidden structures by means of thermography. Frequently output is very poor because testing conditions are not optimized. Hence, appropriate testing requires careful analysis of the wall system before and after taking the thermograms. Otherwise, false alarms render the images useless. This paper describes a general procedure applied to see the hidden wall structure. It works in three steps: a) a mathematical simulation of the real test by a dedicated software, implementing the 3D thermal problem; b) a transient thermographic test, delivering a suitable heating flux on the surface for the proper time; c) processing test data, including a thermogram sequence and air temperature analysis. Here, are reported tests achieved on a XV-XVIIth century Palace at Cremona (Italy; in the Westcott House in Springfield (OH).

  8. Hidden Covariation Detection Produces Faster, Not Slower, Social Judgments

    ERIC Educational Resources Information Center

    Barker, Lynne A.; Andrade, Jackie

    2006-01-01

    In P. Lewicki's (1986b) demonstration of hidden covariation detection (HCD), responses of participants were slower to faces that corresponded with a covariation encountered previously than to faces with novel covariations. This slowing contrasts with the typical finding that priming leads to faster responding and suggests that HCD is a unique type…

  9. Simple yet Hidden Counterexamples in Undergraduate Real Analysis

    ERIC Educational Resources Information Center

    Shipman, Barbara A.; Shipman, Patrick D.

    2013-01-01

    We study situations in introductory analysis in which students affirmed false statements as true, despite simple counterexamples that they easily recognized afterwards. The study draws attention to how simple counterexamples can become hidden in plain sight, even in an active learning atmosphere where students proposed simple (as well as more…

  10. Was 49: Mirror for a hidden Seyfert 1 galaxy

    NASA Technical Reports Server (NTRS)

    Halpern, Jules; Moran, E.; Kay, L.; Antonucci, R.

    1993-01-01

    Was 49 is an interacting pair of Seyfert galaxies at z = 0.063, one of which contains a hidden Seyfert 1 nucleus as evidenced by the highly polarized broad wings on its Balmer lines. The disk of the main galaxy, Was 49a, appears to be globally photoionized by a powerful continuum source, undoubtedly the hidden Seyfert 1 companion, Was 49b. The intrinsic luminosity of Was 49b is at least 100 times larger than the observed (scattered) luminosity. A single SWP spectrum of the pair, which can be spatially resolved in the large aperture was obtained. A narrow Ly-alpha line was detected from Was 49b, the hidden Seyfert 1, at a flux level consistent with that of an unreddened Seyfert 2 galaxy. The lack of detection of a continuum is consistent with a power-law of v(sup -1) or steeper extrapolated from the optical, again consistent with the spectrum of other Seyfert 2 and hidden Seyfert 1 galaxies.

  11. Discovering the Hidden Treasures of Physical Best and Fitnessgram

    ERIC Educational Resources Information Center

    Wilson, Patti

    2011-01-01

    Physical Best and Fitnessgram have a 25-year history, yet many physical educators have yet to be exposed to their full potential. Exploring the Physical Best Activity Guide worksheets and the "Reports" section of Fitnessgram is like finding buried treasure in one's own back yard. These hidden treasures can help physical educators incorporate the…

  12. Hidden Mathematics Curriculum of Teacher Education: An Example

    ERIC Educational Resources Information Center

    Abramovich, Sergei

    2009-01-01

    This article reflects on the author's experience in teaching courses in mathematics content and methods in teacher preparation programs. It shows how technology-enhanced inquiry into a seemingly mundane task on situated addition found in a popular textbook for prospective elementary teachers, can reveal hidden properties of integers associated…

  13. Student and Faculty Reflections of the Hidden Curriculum.

    PubMed

    Bandini, Julia; Mitchell, Christine; Epstein-Peterson, Zachary D; Amobi, Ada; Cahill, Jonathan; Peteet, John; Balboni, Tracy; Balboni, Michael J

    2017-02-01

    The hidden curriculum, or the socialization process of medical training, plays a crucial role in the development of physicians, as they navigate the clinical learning environment. The purpose of this qualitative study was to examine medical faculty and students' perceptions of psychological, moral, and spiritual challenges during medical training in caring for critically ill patients. Focus groups were conducted with 25 Harvard Medical School (HMS) students, and interviews were conducted with 8 HMS faculty members. Five major themes emerged as important in shaping students' medical training experiences. First, students and faculty discussed the overall significance of the hidden curriculum in terms of the hierarchy of medicine, behavioral modeling, and the value placed on research versus clinical work. Second, respondents articulated values modeled in medicine. Third, students and faculty reflected on changes in student development during their training, particularly in terms of changes in empathy and compassion. Fourth, respondents discussed challenges faced in medical school including professional clinical education and the psychosocial aspects of medical training. Finally, students and faculty articulated a number of coping mechanisms to mitigate these challenges including reflection, prayer, repression, support systems, creative outlets, exercise, and separation from one's work. The results from this study suggest the significance of the hidden curriculum on medical students throughout their training, as they learn to navigate challenging and emotional experiences. Furthermore, these results emphasize an increased focus toward the effect of the hidden curriculum on students' development in medical school, particularly noting the ways in which self-reflection may benefit students.

  14. Progressing to University: Hidden Messages at Two State Schools

    ERIC Educational Resources Information Center

    Donnelly, Michael

    2015-01-01

    This paper considers some of the ways that schools play a role in shaping higher education (HE) decision-making. Through their everyday practices and processes, schools can carry hidden messages about progression to HE, including choice of university. The sorts of routine aspects of school life dealt with here include events and activities,…

  15. Is There Hidden Potential for Rural Population Growth in Sweden?

    ERIC Educational Resources Information Center

    Niedomysl, Thomas; Amcoff, Jan

    2011-01-01

    Rural depopulation is a concern in many countries, and various policy initiatives have been taken to combat such trends. This article examines whether hidden potential for rural population growth can be found in Sweden. If such potential exists, it implies that the development prospects for many rural areas are not as unpromising as they may seem…

  16. Hidden Mathematics Curriculum of Teacher Education: An Example

    ERIC Educational Resources Information Center

    Abramovich, Sergei

    2009-01-01

    This article reflects on the author's experience in teaching courses in mathematics content and methods in teacher preparation programs. It shows how technology-enhanced inquiry into a seemingly mundane task on situated addition found in a popular textbook for prospective elementary teachers, can reveal hidden properties of integers associated…

  17. Discovering the Hidden Treasures of Physical Best and Fitnessgram

    ERIC Educational Resources Information Center

    Wilson, Patti

    2011-01-01

    Physical Best and Fitnessgram have a 25-year history, yet many physical educators have yet to be exposed to their full potential. Exploring the Physical Best Activity Guide worksheets and the "Reports" section of Fitnessgram is like finding buried treasure in one's own back yard. These hidden treasures can help physical educators incorporate the…

  18. Education as Text: The Varieties of Educational Hiddenness.

    ERIC Educational Resources Information Center

    Gordon, David

    1988-01-01

    Using the ideas of Paul Ricoeur and Clifford Geertz, this article develops the notion of education as a "text" and analyzes the "hidden curriculum" of that text as it is read by all members of the society. The hypothesis is proposed that education becomes a text about society's myths and sacred beliefs. (TE)

  19. StegoWall: blind statistical detection of hidden data

    NASA Astrophysics Data System (ADS)

    Voloshynovskiy, Sviatoslav V.; Herrigel, Alexander; Rytsar, Yuri B.; Pun, Thierry

    2002-04-01

    Novel functional possibilities, provided by recent data hiding technologies, carry out the danger of uncontrolled (unauthorized) and unlimited information exchange that might be used by people with unfriendly interests. The multimedia industry as well as the research community recognize the urgent necessity for network security and copyright protection, or rather the lack of adequate law for digital multimedia protection. This paper advocates the need for detecting hidden data in digital and analog media as well as in electronic transmissions, and for attempting to identify the underlying hidden data. Solving this problem calls for the development of an architecture for blind stochastic hidden data detection in order to prevent unauthorized data exchange. The proposed architecture is called StegoWall; its key aspects are the solid investigation, the deep understanding, and the prediction of possible tendencies in the development of advanced data hiding technologies. The basic idea of our complex approach is to exploit all information about hidden data statistics to perform its detection based on a stochastic framework. The StegoWall system will be used for four main applications: robust watermarking, secret communications, integrity control and tamper proofing, and internet/network security.

  20. Predicting DataSpace Retrieval Using Probabilistic Hidden Information

    NASA Astrophysics Data System (ADS)

    Fanzou Tchuissang, Gile Narcisse; Wang, Ning; Kuicheu, Nathalie Cindy; Siewe, Francois; Xu, De; Liu, Shuoyan

    This paper discusses the issues involved in the design of a complete information retrieval system for DataSpace based on user relevance probabilistic schemes. First, Information Hidden Model (IHM) is constructed taking into account the users' perception of similarity between documents. The system accumulates feedback from the users and employs it to construct user oriented clusters. IHM allows integrating uncertainty over multiple, interdependent classifications and collectively determines the most likely global assignment. Second, Three different learning strategies are proposed, namely query-related UHH, UHB and UHS (User Hidden Habit, User Hidden Background, and User Hidden keyword Semantics) to closely represent the user mind. Finally, the probability ranking principle shows that optimum retrieval quality can be achieved under certain assumptions. An optimization algorithm to improve the effectiveness of the probabilistic process is developed. We first predict the data sources where the query results could be found. Therefor, compared with existing approaches, our precision of retrieval is better and do not depend on the size and the DataSpace heterogeneity.

  1. Is There Hidden Potential for Rural Population Growth in Sweden?

    ERIC Educational Resources Information Center

    Niedomysl, Thomas; Amcoff, Jan

    2011-01-01

    Rural depopulation is a concern in many countries, and various policy initiatives have been taken to combat such trends. This article examines whether hidden potential for rural population growth can be found in Sweden. If such potential exists, it implies that the development prospects for many rural areas are not as unpromising as they may seem…

  2. Classical simulation of quantum entanglement without local hidden variables

    NASA Astrophysics Data System (ADS)

    Massar, Serge; Bacon, Dave; Cerf, Nicolas J.; Cleve, Richard

    2001-05-01

    Recent work has extended Bell's theorem by quantifying the amount of communication required to simulate entangled quantum systems with classical information. The general scenario is that a bipartite measurement is given from a set of possibilities and the goal is to find a classical scheme that reproduces exactly the correlations that arise when an actual quantum system is measured. Previous results have shown that, using local hidden variables, a finite amount of communication suffices to simulate the correlations for a Bell state. We extend this in a number of ways. First, we show that, when the communication is merely required to be finite on average, Bell states can be simulated without any local hidden variables. More generally, we show that arbitrary positive operator valued measurements on systems of n Bell states can be simulated with O(n2n) bits of communication on average (again, without local hidden variables). On the other hand, when the communication is required to be absolutely bounded, we show that a finite number of bits of local hidden variables is insufficient to simulate a Bell state. This latter result is based on an analysis of the nondeterministic communication complexity of the NOT-EQUAL function, which is constant in the quantum model and logarithmic in the classical model.

  3. A quirky probe of neutral naturalness

    NASA Astrophysics Data System (ADS)

    Chacko, Zackaria; Curtin, David; Verhaaren, Christopher B.

    2016-07-01

    We consider the signals arising from top partner pair production at the LHC as a probe of theories of neutral naturalness. We focus on scenarios in which top partners carry electroweak charges, such as folded supersymmetry or the quirky little Higgs. In this class of theories the top partners are pair produced as quirky bound states, since they are charged under a mirror color group whose lightest states are hidden glueballs. The quirks promptly de-excite and annihilate into glueballs, which decay back to Standard Model fermions via Higgs mixing. This can give rise to spectacular signatures at the LHC, such displaced decays, or high-multiplicity prompt production of many hard b ¯b or τ+τ- pairs. We show that signals arising from top partner pair production constitute the primary discovery channel for this class of theories in most regions of parameter space, and might provide the only experimental probe of scenarios with sub-cm glueball decay lengths. The measurement of top partner masses and couplings, which could be used to test the neutral naturalness mechanism directly, is also a tantalizing possibility.

  4. Rotary probe traversing mechanism

    NASA Astrophysics Data System (ADS)

    Hokenson, Gustave J.

    1985-04-01

    A simple mechanical device is presented which allows a probe to scan a plane in space without translating the probe support. The mechanism relies on the rotation of two shafts, one of which rotates the probe through space and the other controls the probe offset from the axis of rotation. The characteristic width of the area swept out is four times the characteristic width of the device. A simple ratcheting gear allows adjacent planes to be scanned for the purpose of obtaining gradients. Computerized control of the shafts rotations also allows noncircular domains to be scanned.

  5. Transient internal probe

    NASA Astrophysics Data System (ADS)

    Jarboe, Thomas R.; Mattick, Arthur T.

    1993-12-01

    The Transient Internal Probe (TIP) diagnostic is a novel method for probing the interior of hot magnetic fusion plasmas that are inaccessible with ordinary stationary probes. A small probe of magneto-optic (Verdet) material is fired through a plasma at speeds of several km/sec, illuminated by a laser beam. The beam's polarization is rotated in the probe by the local magnetic field and retroreflection back to a polarimetry detector allows determination of the B-field profile across the diameter of a plasma at a spatial resolution of better than 1-cm and an absolute B-field resolution of a few tens of Gauss. The principal components of a TIP diagnostic system were developed and tested. A two-stage light gas gun was constructed that accelerates 30-caliber projectiles to 3 km/sec, and methods were examined for stripping a lexan sabot from a probe prior to entry into a plasma. Probes of CdMnTe and FR-5 Verdet glass were fabricated, and a polarimetry system was constructed for resolving polarization to within 0.25 deg. The diagnostic was validated by measuring a static B-field with a moving (dropped) TIP probe, and finding agreement with Hall-probe measurements to within experimental accuracy (40 Gauss).

  6. Rocket exhaust probe

    NASA Astrophysics Data System (ADS)

    Kessel, P. A.

    1986-01-01

    Disclosed is a rocket exhaust probe for collecting particulates from a rocket exhaust plume. The probe comprises a tungsten nose tip, a tip holder, a probe body, and a tail section. Rocket exhaust gas enters the probe at the nose tip inlet and passes into a mixing chamber where the exhaust gas mixes with an inert cooling gas that cools and decelerates the exhaust gas. The mixture of exhaust gas and inert gas then passes into a diffusion chamber where it further cools and decelerates before passsing through a submicron particle collection filter.

  7. Hearing the signal of dark sectors with gravitational wave detectors

    NASA Astrophysics Data System (ADS)

    Jaeckel, Joerg; Khoze, Valentin V.; Spannowsky, Michael

    2016-11-01

    Motivated by advanced LIGO (aLIGO)'s recent discovery of gravitational waves, we discuss signatures of new physics that could be seen at ground- and space-based interferometers. We show that a first-order phase transition in a dark sector would lead to a detectable gravitational wave signal at future experiments, if the phase transition has occurred at temperatures few orders of magnitude higher than the electroweak scale. The source of gravitational waves in this case is associated with the dynamics of expanding and colliding bubbles in the early universe. At the same time we point out that topological defects, such as dark sector domain walls, may generate a detectable signal already at aLIGO. Both bubble and domain-wall scenarios are sourced by semiclassical configurations of a dark new physics sector. In the first case, the gravitational wave signal originates from bubble wall collisions and subsequent turbulence in hot plasma in the early universe, while the second case corresponds to domain walls passing through the interferometer at present and is not related to gravitational waves. We find that aLIGO at its current sensitivity can detect smoking-gun signatures from domain-wall interactions, while future proposed experiments including the fifth phase of aLIGO at design sensitivity can probe dark sector phase transitions.

  8. Hidden Owners, Hidden Profits, and Poor Nursing Home Care: A Case Study.

    PubMed

    Harrington, Charlene; Ross, Leslie; Kang, Taewoon

    2015-01-01

    The study examined the ownership transparency, financial accountability, and quality indicators of a regional for-profit nursing home chain in California, using a case study methodology to analyze data on the chain's ownership and management structure, financial data, staffing levels, deficiencies and complaints, and litigation. Secondary data were obtained from regulatory and cost reports and litigation cases. Qualitative descriptions of ownership and management were presented and quantitative analyses were conducted by comparing financial and quality indicators with other California for-profit chains, for-profit non-chains, and nonprofit nursing home groups in 2011. The chain's complex, interlocking individual and corporate owners and property companies obscured its ownership structure and financial arrangements. Nursing and support services expenditures were lower than nonprofits and administrative costs were higher than for-profit non-chains. The chain's nurse staffing was lower than expected staffing levels; its deficiencies and citations were higher than in nonprofits; and a number of lawsuits resulted in bankruptcy. Profits were hidden in the chain's management fees, lease agreements, interest payments to owners, and purchases from related-party companies. Greater ownership transparency and financial accountability requirements are needed to ensure regulatory oversight and quality of care.

  9. Spatially Enabling the Health Sector

    PubMed Central

    Weeramanthri, Tarun Stephen; Woodgate, Peter

    2016-01-01

    Spatial information describes the physical location of either people or objects, and the measured relationships between them. In this article, we offer the view that greater utilization of spatial information and its related technology, as part of a broader redesign of the architecture of health information at local and national levels, could assist and speed up the process of health reform, which is taking place across the globe in richer and poorer countries alike. In making this point, we describe the impetus for health sector reform, recent developments in spatial information and analytics, and current Australasian spatial health research. We highlight examples of uptake of spatial information by the health sector, as well as missed opportunities. Our recommendations to spatially enable the health sector are applicable to high- and low-resource settings. PMID:27867933

  10. Network topology of economic sectors

    NASA Astrophysics Data System (ADS)

    Djauhari, Maman A.; Gan, Siew Lee

    2016-09-01

    A lot of studies dealing with stock network analysis, where each individual stock is represented by a univariate time series of its closing price, have been published. In these studies, the similarity of two different stocks is quantified using a Pearson correlation coefficient on the logarithmic price returns. In this paper, we generalize the notion of similarity between univariate time series into multivariate time series which might be of different dimensions. This allows us to deal with economic sector network analysis, where the similarity between economic sectors is defined using Escoufier’s vector correlation RV. To the best of our knowledge, there is no study dealing with this notion of economic sector similarity. Two examples of data from the New York stock exchange will be presented and discussed, and some important results will be highlighted.

  11. PeV-scale dark matter as a thermal relic of a decoupled sector

    NASA Astrophysics Data System (ADS)

    Berlin, Asher; Hooper, Dan; Krnjaic, Gordan

    2016-09-01

    In this letter, we consider a class of scenarios in which the dark matter is part of a heavy hidden sector that is thermally decoupled from the Standard Model in the early universe. The dark matter freezes-out by annihilating to a lighter, metastable state, whose subsequent abundance can naturally come to dominate the energy density of the universe. When this state decays, it reheats the visible sector and dilutes all relic abundances, thereby allowing the dark matter to be orders of magnitude heavier than the weak scale. For concreteness, we consider a simple realization with a Dirac fermion dark matter candidate coupled to a massive gauge boson that decays to the Standard Model through its kinetic mixing with hypercharge. We identify viable parameter space in which the dark matter can be as heavy as ∼1-100 PeV without being overproduced in the early universe.

  12. PeV-scale dark matter as a thermal relic of a decoupled sector

    DOE PAGES

    Berlin, Asher; Hooper, Dan; Krnjaic, Gordan

    2016-06-21

    We consider a class of scenarios in which the dark matter is part of a heavy hidden sector that is thermally decoupled from the Standard Model in the early universe. The dark matter freezes-out by annihilating to a lighter, metastable state, whose subsequent abundance can naturally come to dominate the energy density of the universe. Moreover, when this state decays, it reheats the visible sector and dilutes all relic abundances, thereby allowing the dark matter to be orders of magnitude heavier than the weak scale. For concreteness, we consider a simple realization with a Dirac fermion dark matter candidate coupledmore » to a massive gauge boson that decays to the Standard Model through its kinetic mixing with hypercharge. Finally, we identify viable parameter space in which the dark matter can be as heavy as ~1-100 PeV without being overproduced in the early universe.« less

  13. The District and Charter Sectors of American K-12 Education: Pros and Cons

    ERIC Educational Resources Information Center

    Finn, Chester E., Jr.; Manno, Bruno V.; Wright, Brandon L.

    2017-01-01

    This article probes ways in which the school-choice marketplace as it developed via chartering has not worked as well in practice as many had hoped. It includes reflection on the profoundly different operating principles and theories of action that separate the district and charter sectors in their pure forms. It also offers market-strengthening…

  14. The District and Charter Sectors of American K-12 Education: Pros and Cons

    ERIC Educational Resources Information Center

    Finn, Chester E., Jr.; Manno, Bruno V.; Wright, Brandon L.

    2017-01-01

    This article probes ways in which the school-choice marketplace as it developed via chartering has not worked as well in practice as many had hoped. It includes reflection on the profoundly different operating principles and theories of action that separate the district and charter sectors in their pure forms. It also offers market-strengthening…

  15. Hidden corrosion detection with guided waves

    SciTech Connect

    Rose, J.L.; Jiao, D.; Pelts, S.P.; Barshinger, J.N.; Quarry, M.J.

    1997-12-01

    A corrosion detection feasibility study with ultrasonic guided waves is presented. Rather than use normal beam ultrasonic techniques that move point by point over the structure being examined, guided waves are more global in nature allowing examination of regions over 2--3 cm on up to 4--5m with reasonable efficiency in corrosion detection and in estimating average wall thickness between the two transducers. A sample problem in aging aircraft inspection for fuselage thinning is studied and used to illustrate the guided wave inspection procedure and potential for classification and sizing analysis. Special sensitivities to certain kinds of defects are possible with guided waves as a result of wave structure changes across the thickness of the structure by simple mode and frequency changes. A variable angle beam probe and multiple array comb type transducer are considered for flexibility in mode selection and isolation on the dispersion diagrams in order to achieve the special wave structures required for corrosion detection and also for reasonable penetration power. Going beyond the initial feasibility study of guided wave application for the detection of corrosion, a number of tools are developed that can be used in future work to more accurately detect, size, and classify corrosion types in various structures. Boundary element modeling analysis, for example, allows the calculation of reflection and transmission factors for a particular mode and frequency input to a particular pitting or corrosion type defect. This can be followed by detailed feature analysis for subsequent use in neural net algorithm development for corrosion analysis. The physically based features from guided wave analysis can then be used to provide insight and guidance into the algorithm development program using pattern recognition and neural nets.

  16. Economic Indicators of the Farm Sector. Farm Sector Review, 1986.

    ERIC Educational Resources Information Center

    Economic Research Service (USDA), Washington, DC.

    This report contains 44 tables and 23 figures, along with narrative summaries, that provide an overall view of the farm sector in the United States in 1986. Some of the findings highlighted in the report are the following: (1) farmers spent less to produce their crops and livestock in 1986; (2) government payments to farmers increased, but prices…

  17. A New Class of Three-Dimensional Maps with Hidden Chaotic Dynamics

    NASA Astrophysics Data System (ADS)

    Jiang, Haibo; Liu, Yang; Wei, Zhouchao; Zhang, Liping

    This paper studies a new class of three-dimensional maps in a Jerk-like structure with a special concern of their hidden chaotic dynamics. Our investigation focuses on the hidden chaotic attractors in three typical scenarios of fixed points, namely no fixed point, single fixed point, and two fixed points. A systematic computer search is performed to explore possible hidden chaotic attractors, and a number of examples of the proposed maps are used for demonstration. Numerical results show that the routes to hidden chaotic attractors are complex, and the basins of attraction for the hidden chaotic attractors could be tiny, so that using the standard computational procedure for localization is impossible.

  18. Probing Skills for Tutors.

    ERIC Educational Resources Information Center

    Brown, Beryl E.

    The Office of Academic Support and Instructional Services (OASIS) at the University of California at San Diego sponsors a workshop that teaches tutors to use five types of probing skills. The use of the skills is fundamental to the student learner's acquisition of complex relationships and problem solving skills. The five types of probes are:…

  19. Formative Assessment Probes

    ERIC Educational Resources Information Center

    Eberle, Francis; Keeley, Page

    2008-01-01

    Formative assessment probes can be effective tools to help teachers build a bridge between students' initial ideas and scientific ones. In this article, the authors describe how using two formative assessment probes can help teachers determine the extent to which students make similar connections between developing a concept of matter and a…

  20. Formative Assessment Probes

    ERIC Educational Resources Information Center

    Eberle, Francis; Keeley, Page

    2008-01-01

    Formative assessment probes can be effective tools to help teachers build a bridge between students' initial ideas and scientific ones. In this article, the authors describe how using two formative assessment probes can help teachers determine the extent to which students make similar connections between developing a concept of matter and a…