WorldWideScience

Sample records for suspected orbital periods

  1. Measuring Scars of Periodic Orbits

    CERN Document Server

    Kaplan, L

    1999-01-01

    The phenomenon of periodic orbit scarring of eigenstates of classically chaotic systems is attracting increasing attention. Scarring is one of the most important ``corrections'' to the ideal random eigenstates suggested by random matrix theory. This paper discusses measures of scars and in so doing also tries to clarify the concepts and effects of eigenfunction scarring. We propose a new, universal scar measure which takes into account an entire periodic orbit and the linearized dynamics in its vicinity. This measure is tuned to pick out those structures which are induced in quantum eigenstates by unstable periodic orbits and their manifolds. It gives enhanced scarring strength as measured by eigenstate overlaps and inverse participation ratios, especially for longer orbits. We also discuss off-resonance scars which appear naturally on either side of an unstable periodic orbit.

  2. Periodic Orbits and Deformed Shell Structure

    OpenAIRE

    Arita, K.; Magner, A. G.; Matsuyanagi, K.

    2002-01-01

    Relationship between quantum shell structure and classical periodic orbits is briefly reviewed on the basis of semi-classical trace formula. Using the spheroidal cavity model, it is shown that three-dimensional periodic orbits, which are born out of bifurcation of planar orbits at large prolate deformations, generate the superdeformed shell structure.

  3. Wavefunction Intensity Statistics from Unstable Periodic Orbits

    CERN Document Server

    Kaplan, L

    1998-01-01

    We examine the effect of short unstable periodic orbits on wavefunction statistics in a classically chaotic system, and find that the tail of the wavefunction intensity distribution in phase space is dominated by scarring associated with the least unstable periodic orbits. In an ensemble average over systems with classical orbits of different instabilities, a power law tail is found, in sharp contrast to the exponential prediction of random matrix theory. The calculations are compared with numerical data and quantitative agreement is obtained

  4. Numerical bifurcation of Hamiltonian relative periodic orbits

    DEFF Research Database (Denmark)

    Wulff, Claudia; Schilder, Frank

    2009-01-01

    Relative periodic orbits (RPOs) are ubiquitous in symmetric Hamiltonian systems and occur, for example, in celestial mechanics, molecular dynamics, and the motion of rigid bodies. RPOs are solutions which are periodic orbits of the symmetry-reduced system. In this paper we analyze certain symmetry...

  5. Superluminal periodic orbits in the Lorenz system

    Science.gov (United States)

    Algaba, A.; Merino, M.; Rodríguez-Luis, A. J.

    2016-10-01

    In this work we present, for the Lorenz system, analytical and numerical results on the existence of periodic orbits with unbounded amplitude and whose period tends to zero. Since a particle moving on these periodic orbits would be faster-than-light, we call them superluminal periodic orbits. To achieve this goal, we first find analytical expressions for the period in three different situations, where Hopf and Takens-Bogdanov bifurcations of infinite codimension occur. Thus, taking limit in the corresponding expressions allows to demonstrate the existence of superluminal periodic orbits for finite values of the parameter ρ (in a region where the other two parameters σ and b are negative). Moreover, we numerically show, in other two different cases of physical interest, that these orbits also exist when the parameter ρ tends to infinity. Finally, the presence of superluminal periodic orbits in the widely studied Chen and Lü systems follows directly from our results, taking into account that they are, generically, particular cases of the Lorenz system, as can be proved with a linear scaling in time and state variables.

  6. Established meteor shower activity periods and orbits

    Science.gov (United States)

    Roggemans, Paul

    2017-02-01

    The CAMS dataset of 111233 orbits collected in the period 2010-2013 has been checked to verify the online data of the IAU meteor shower list. The activity periods for all meteor streams detected in CAMS data has been derived from the solar longitudes of the individual orbits that were associated with the meteor stream. For meteor showers that were absent in the CAMS data, mainly daylight meteor streams, CMOR data has been used to complete the information. To make future associations easier and to avoid mixing up shower data, the official naming and IAU code with the orbital elements are listed in this contribution.

  7. Clustering of periodic orbits in chaotic systems

    Science.gov (United States)

    Gutkin, Boris; Osipov, Vladimir Al

    2013-01-01

    In the framework of the semiclassical approach, the universal spectral correlations in Hamiltonian systems with classical chaotic dynamics can be attributed to the systematic correlations between the actions of periodic orbits which (up to the switch in the momentum direction) pass through approximately the same points of the phase space. By considering symbolic dynamics of the system one can introduce a natural ultrametric distance between periodic orbits and organize them into clusters of orbits approaching each other in the phase space. We study the distribution of cluster sizes for the baker's map in the asymptotic limit of long trajectories. This problem is equivalent to the one of counting degeneracies in the length spectrum of the de Bruijn graphs. Based on this fact, we derive the probability P_k that k randomly chosen periodic orbits belong to the same cluster. Furthermore, we find asymptotic behaviour of the largest cluster size |C_{\\max}| and derive the probability P(t) that a random periodic orbit belongs to a cluster smaller than t|C_{\\max}| , t ∈ [0, 1].

  8. Periodic orbits near a bifurcating slow manifold

    DEFF Research Database (Denmark)

    Kristiansen, Kristian Uldall

    2015-01-01

    (\\epsilon^{1/3})$-distance from the union of the normally elliptic slow manifolds that occur as a result of the bifurcation. Here $\\epsilon\\ll 1$ measures the time scale separation. These periodic orbits are predominantly unstable. The proof is based on averaging of two blowup systems, allowing one to estimate...... the effect of the singularity, combined with results on asymptotics of the second Painleve equation. The stable orbits of smallest amplitude that are {persistently} obtained by these methods remain slightly further away from the slow manifold being distant by an order $\\mathcal O(\\epsilon^{1/3}\\ln^{1/2}\\ln...

  9. Periodic orbits and TDHF phase space structure

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Yukio; Iwasawa, Kazuo [Tsukuba Univ., Ibaraki (Japan). Inst. of Physics; Tsukuma, Hidehiko; Sakata, Fumihiko

    1998-03-01

    The collective motion of atomic nuclei is closely coupled with the motion of nucleons, therefore, it is nonlinear, and the contents of the motion change largely with the increase of its amplitude. As the framework which describes the collective motion accompanied by the change of internal structure, time-dependent Hurtley Fock (TDHF) method is suitable. At present, the authors try to make the method for studying the large region structure in quantum system by utilizing the features of the TDHF phase space. The studies made so far are briefed. In this report, the correspondence of the large region patterns appearing in the band structure chart of three-level model with the periodic orbit group in the TDHF phase space is described. The Husimi function is made, and it possesses the information on the form of respective corresponding intrinsic state. The method of making the band structure chart is explained. There are three kinds of the tendency in the intrinsic state group. The E-T charts are made for the band structure charts to quantitatively express the large region tendency. The E-T chart and the T{sub r}-T chart are drawn for a selected characteristic orbit group. It became to be known that the large region properties of the quantum intrinsic state group of three-level model can be forecast by examining the properties of the periodic orbit group in the TDHF phase space. (K.I.)

  10. On periodic orbits in discrete-time cascade systems

    Directory of Open Access Journals (Sweden)

    Huimin Li

    2006-01-01

    Full Text Available We present some results on existence, minimum period, number of periodic orbits, and stability of periodic orbits in discrete-time cascade systems. Some examples are presented to illustrate these results.

  11. Periodic orbits near the particle resonance in galaxies

    CERN Document Server

    Contopoulos, George

    1978-01-01

    Near the particle resonance of a spiral galaxy the almost circular periodic orbits that exist inside the resonance (direct) or outside it (retrograde) are replaced by elongated trapped orbits around the maxima of the potential L/sub 4/ and L/sub 5/. These are the long- period trapped periodic orbits. The long-period orbits shrink to the points L/sub 4/, L/sub 5/ for a critical value of the Hamiltonian h. For still larger h, a family of short-period trapped orbits appears, with continuously growing size. The evolution of the periodic orbits with h is followed, theoretically and numerically, from the untrapped orbits to the long-periodic orbits and then to the short-periodic orbits, mainly in the case of a bar. In a tight spiral case an explanation of the asymmetric periodic and banana orbits is given, and an example of short-period orbits not surrounding L/sub 4/ or L/sub 5/ is provided. Another family of periodic orbits reaching corotation is trapped at the inner Lindblad resonance. (5 refs).

  12. PERIODIC-ORBITS IN K-SYMMETRICAL DYNAMICAL-SYSTEMS

    NARCIS (Netherlands)

    BRANDS, H; LAMB, JSW; HOVEIJN, [No Value

    1995-01-01

    A map L is called k-symmetric if its kth iterate L(k) possesses more symmetry than L, for some value of k. In k-symmetric systems, there exists a notion of k-symmetric orbits. This paper deals with k-symmetric periodic orbits. We derive a relation between orbits that are k-symmetric with respect to

  13. The incidence of suspected myocardial infarction in Dutch general practice in the period 1978-1994.

    NARCIS (Netherlands)

    Pal-de Bruin, K.M. van der; Verkleij, H.; Jansen, J.; Bartelds, A.; Kromhout, D.

    1998-01-01

    Aim: To evaluate how the incidence of suspected myocardial infarction has developed from 1978 to 1994 and to study the incidence of confirmed acute myocardial infarction in Dutch general practices during the period 1991-1994. Methods: In three periods (1978, 1983-1985 and 1991-1994) the incidence of

  14. Unstable periodic orbits and attractor of the barotropic ocean model

    Directory of Open Access Journals (Sweden)

    E. Kazantsev

    1998-01-01

    Full Text Available A numerical method for detection of unstable periodic orbits on attractors of nonlinear models is proposed.  The method requires similar techniques to data assimilation.  This fact facilitates its implementation for geophysical models.  This method was used to find numerically several low-period orbits for the barotropic ocean model in a square.  Some numerical particularities of application of this method are discussed. Knowledge of periodic orbits of the model helps to explain some of these features like bimodality of probability density functions (PDF of principal parameters.  These PDFs have been reconstructed as weighted averages of periodic orbits with weights proportional to the period of the orbit and inversely proportional to the sum of positive Lyapunov exponents. The fraction of time spent in the vicinity of each periodic orbit has been compared with its instability characteristics. The relationship between these values shows the 93% correlation.  The attractor dimension of the model has also been approximated as a weighted average of local attractor dimensions in vicinities of periodic orbits.

  15. The 3-dimensional cored and logarithm potentials: Periodic orbits

    Energy Technology Data Exchange (ETDEWEB)

    Kulesza, Maité, E-mail: maite@dm.ufrpe.br [Departamento de Matemática, Universidade Federal Rural de Pernambuco, 52171-900, Recife, Pernambuco (Brazil); Llibre, Jaume, E-mail: jllibre@mat.uab.cat [Departament de Matemàtiques, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia (Spain)

    2014-11-15

    We study analytically families of periodic orbits for the cored and logarithmic Hamiltonians with 3 degrees of freedom, which are relevant in the analysis of the galactic dynamics. First, after introducing a scale transformation in the coordinates and momenta with a parameter ε, we show that both systems give essentially the same set of equations of motion up to first order in ε. Then the conditions for finding families of periodic orbits, using the averaging theory up to first order in ε, apply equally to both systems in every energy level H = h > 0 showing the existence of at least 3 periodic orbits, for ε small enough, and also provides an analytic approximation for the initial conditions of these periodic orbits. We prove that at every positive energy level the cored and logarithmic Hamiltonians with 3 degrees of freedom have at least three periodic solutions. The technique used for proving such a result can be applied to other Hamiltonian systems.

  16. Central configurations, periodic orbits, and Hamiltonian systems

    CERN Document Server

    Llibre, Jaume; Simó, Carles

    2015-01-01

    The notes of this book originate from three series of lectures given at the Centre de Recerca Matemàtica (CRM) in Barcelona. The first one is dedicated to the study of periodic solutions of autonomous differential systems in Rn via the Averaging Theory and was delivered by Jaume Llibre. The second one, given by Richard Moeckel, focusses on methods for studying Central Configurations. The last one, by Carles Simó, describes the main mechanisms leading to a fairly global description of the dynamics in conservative systems. The book is directed towards graduate students and researchers interested in dynamical systems, in particular in the conservative case, and aims at facilitating the understanding of dynamics of specific models. The results presented and the tools introduced in this book include a large range of applications.

  17. Linear and nonlinear stability of periodic orbits in annular billiards.

    Science.gov (United States)

    Dettmann, Carl P; Fain, Vitaly

    2017-04-01

    An annular billiard is a dynamical system in which a particle moves freely in a disk except for elastic collisions with the boundary and also a circular scatterer in the interior of the disk. We investigate the stability properties of some periodic orbits in annular billiards in which the scatterer is touching or close to the boundary. We analytically show that there exist linearly stable periodic orbits of an arbitrary period for scatterers with decreasing radii that are located near the boundary of the disk. As the position of the scatterer moves away from a symmetry line of a periodic orbit, the stability of periodic orbits changes from elliptic to hyperbolic, corresponding to a saddle-center bifurcation. When the scatterer is tangent to the boundary, the periodic orbit is parabolic. We prove that slightly changing the reflection angle of the orbit in the tangential situation leads to the existence of Kolmogorov-Arnold-Moser islands. Thus, we show that there exists a decreasing to zero sequence of open intervals of scatterer radii, along which the billiard table is not ergodic.

  18. Periodic orbits around a spherically symmetric naked singularity

    Science.gov (United States)

    Babar, Gulmina Zaman; Babar, Adil Zaman; Lim, Yen-Kheng

    2017-10-01

    The motion of time-like test particles in the Fisher/Janis-Newman-Winicour (F/JNW) spacetime is studied with the Hamiltonian formulation of the geodesic equations. The spacetime is characterized by its mass parameter rg and scalar field parameter ν . The innermost bound and stable circular orbits are calculated and the effective potential is analyzed. Consistent with numerical results in earlier literature, for ν <1/2 , particles with nonzero angular momentum encounter an infinite potential barrier, preventing them from reaching the naked singularity at r =rg. Periodic orbits in the spacetime are also obtained. Compared to the periodic orbits around the Schwarzschild black hole, it is found that typically lower energies are required for the same orbits in the F/JNW spacetime.

  19. Use of high order, periodic orbits in the PIES code

    Science.gov (United States)

    Monticello, Donald; Reiman, Allan

    2010-11-01

    We have implemented a version of the PIES code (Princeton Iterative Equilibrium SolverootnotetextA. Reiman et al 2007 Nucl. Fusion 47 572) that uses high order periodic orbits to select the surfaces on which straight magnetic field line coordinates will be calculated. The use of high order periodic orbits has increase the robustness and speed of the PIES code. We now have more uniform treatment of in-phase and out-of-phase islands. This new version has better convergence properties and works well with a full Newton scheme. We now have the ability to shrink islands using a bootstrap like current and this includes the m=1 island in tokamaks.

  20. Detecting unstable periodic orbits in chaotic time series using synchronization

    Science.gov (United States)

    Olyaei, Ali Azimi; Wu, Christine; Kinsner, Witold

    2017-07-01

    An alternative approach of detecting unstable periodic orbits in chaotic time series is proposed using synchronization techniques. A master-slave synchronization scheme is developed, in which the chaotic system drives a system of harmonic oscillators through a proper coupling condition. The proposed scheme is designed so that the power of the coupling signal exhibits notches that drop to zero once the system approaches an unstable orbit yielding an explicit indication of the presence of a periodic motion. The results shows that the proposed approach is particularly suitable in practical situations, where the time series is short and noisy, or it is obtained from high-dimensional chaotic systems.

  1. Uncertainty and anxiety during the diagnostic period for women with suspected breast cancer.

    Science.gov (United States)

    Liao, Mei-Nan; Chen, Miin-Fu; Chen, Shin-Cheh; Chen, Ping-Ling

    2008-01-01

    A possible diagnosis of breast cancer imposes a huge psychological impact on most women, but few studies have addressed uncertainty and anxiety changes at different diagnostic stages in women with suspected breast cancer. Thus, this longitudinal study examined uncertainty and anxiety and predictive factors for uncertainty in women with suspected breast cancer. Data were collected on uncertainty (Uncertainty in Illness Scale) and anxiety (State Anxiety Inventory) from 127 women at 3 times: upon notice of a breast biopsy, before biopsy, and after diagnosis. The results showed that uncertainty and anxiety levels were significantly higher before than after diagnosis. At the 3 data collection times, uncertainty and anxiety were significantly lower for participants diagnosed with benign tumors than for those with malignant diagnoses. Uncertainty and anxiety were positively, moderately correlated. Uncertainty was predicted by age, marital status, education level, religious status, family history of benign breast tumor, regular breast self-examination, self-perceived probability of receiving a breast cancer diagnosis, and biopsy result. Therefore, nursing professionals should be aware of the uncertainty and anxiety changes and impact of personal attributes on women with suspected breast cancer during the diagnostic period and provide care programs to alleviate their psychological distress.

  2. Progress in the analysis of experimental chaos through periodic orbits

    Energy Technology Data Exchange (ETDEWEB)

    Badii, R. (Paul Scherrer Institute, CH-5232 Villigen (Switzerland)); Brun, E. (Physics Institute, University of Zuerich, CH-8057 Zuerich (Switzerland)); Finardi, M. (Paul Scherrer Institute, CH-5232 Villigen (Switzerland)); Flepp, L.; Holzner, R.; Parisi, J.; Reyl, C.; Simonet, J. (Physics Institute, University of Zuerich, CH-8057 Zuerich (Switzerland))

    1994-10-01

    The understanding of chaotic systems can be considerably improved with the knowledge of their periodic-orbit structure. The identification of the low-order unstable periodic orbits embedded in a strange attractor induces a hierarchical organization of the dynamics which is invariant under smooth coordinate changes. The applicability of this technique is by no means limited to analytical or numerical calculations, but has been recently extended to experimental time series. As a specific example, the authors review some of the major results obtained on a nuclear-magnetic-resonance laser which have led to an extension of the conventional (Bloch-Kirchhoff) equations of motion, to the construction of approximate generating partitions, and to an efficient control of the chaotic system around various unstable periodic orbits. The determination of the symbolic dynamics, with the precision achieved by recording all unstable cycles up to order 9, improves the topological and metric characterization of a heteroclinic crisis. The periodic-orbit approach permits detailed study of chaotic motion, thereby leading to an improved classification scheme which subsumes the older ones, based on estimates of scalar quantities such as fractal dimensions and metric entropies.

  3. Periodic orbits of nonscaling Hamiltonian systems from quantum mechanics.

    Science.gov (United States)

    Baranger, M.; Haggerty, M. R.; Lauritzen, B.; Meredith, D. C.; Provost, D.

    1995-03-01

    Quantal (E,tau) plots are constructed from the eigenvalues of the quantum system. We demonstrate that these representations display the periodic orbits of the classical system, including bifurcations and the transition from stable to unstable. (c) 1995 American Institute of Physics.

  4. Evidence for a Long-Period Planet Orbiting ɛ Eridani

    Science.gov (United States)

    Hatzes, Artie P.; Cochran, William D.; McArthur, Barbara; Baliunas, Sallie L.; Walker, Gordon A. H.; Campbell, Bruce; Irwin, Alan W.; Yang, Stephenson; Kürster, Martin; Endl, Michael; Els, Sebastian; Butler, R. Paul; Marcy, Geoffrey W.

    2000-12-01

    High-precision radial velocity (RV) measurements spanning the years 1980.8-2000.0 are presented for the nearby (3.22 pc) K2 V star ɛ Eri. These data, which represent a combination of six independent data sets taken with four different telescopes, show convincing variations with a period of ~7 yr. A least-squares orbital solution using robust estimation yields orbital parameters of period P=6.9 yr, velocity amplitude K=19 m s-1, eccentricity e=0.6, projected companion mass Msini=0.86 MJupiter, and semimajor axis a2=3.4 AU. Ca II H and K S-index measurements spanning the same time interval show significant variations with periods of 3 and 20 yr yet none at the RV period. If magnetic activity were responsible for the RV variations, then it produces a significantly different period than is seen in the Ca II data. Given the lack of Ca II variation with the same period as that found in the RV measurements, the long-lived and coherent nature of these variations, and the high eccentricity of the implied orbit, Keplerian motion due to a planetary companion seems to be the most likely explanation for the observed RV variations. The wide angular separation of the planet from the star (approximately 1") and the long orbital period make this planet a prime candidate for both direct imaging and space-based astrometric measurements. Based on observations collected at McDonald Observatory, Lick Observatory, European Southern Observatory at La Silla, and the Canada-France-Hawaii Telescope.

  5. About Tidal Evolution of Quasi-Periodic Orbits of Satellites

    Science.gov (United States)

    Ershkov, Sergey V.

    2017-06-01

    Tidal interactions between Planet and its satellites are known to be the main phenomena, which are determining the orbital evolution of the satellites. The modern ansatz in the theory of tidal dissipation in Saturn was developed previously by the international team of scientists from various countries in the field of celestial mechanics. Our applying to the theory of tidal dissipation concerns the investigating of the system of ODE-equations (ordinary differential equations) that govern the orbital evolution of the satellites; such an extremely non-linear system of 2 ordinary differential equations describes the mutual internal dynamics for the eccentricity of the orbit along with involving the semi-major axis of the proper satellite into such a monstrous equations. In our derivation, we have presented the elegant analytical solutions to the system above; so, the motivation of our ansatz is to transform the previously presented system of equations to the convenient form, in which the minimum of numerical calculations are required to obtain the final solutions. Preferably, it should be the analytical solutions; we have presented the solution as a set of quasi- periodic cycles via re-inversing of the proper ultra- elliptical integral. It means a quasi-periodic character of the evolution of the eccentricity, of the semi-major axis for the satellite orbit as well as of the quasi-periodic character of the tidal dissipation in the Planet.

  6. Theory of short periodic orbits for partially open quantum maps.

    Science.gov (United States)

    Carlo, Gabriel G; Benito, R M; Borondo, F

    2016-07-01

    We extend the semiclassical theory of short periodic orbits [M. Novaes et al., Phys. Rev. E 80, 035202(R) (2009)PLEEE81539-375510.1103/PhysRevE.80.035202] to partially open quantum maps, which correspond to classical maps where the trajectories are partially bounced back due to a finite reflectivity R. These maps are representative of a class that has many experimental applications. The open scar functions are conveniently redefined, providing a suitable tool for the investigation of this kind of system. Our theory is applied to the paradigmatic partially open tribaker map. We find that the set of periodic orbits that belongs to the classical repeller of the open map (R=0) is able to support the set of long-lived resonances of the partially open quantum map in a perturbative regime. By including the most relevant trajectories outside of this set, the validity of the approximation is extended to a broad range of R values. Finally, we identify the details of the transition from qualitatively open to qualitatively closed behavior, providing an explanation in terms of short periodic orbits.

  7. Orbits for two short-period and two long-period binaries

    Science.gov (United States)

    Cvetković, Z.; Ninković, S.

    2008-11-01

    In this paper, new orbital elements and the quantities following from them for four binaries are analysed. For three of them, WDS 04340 + 1510 = CHR 17, WDS 06290 + 2013 = BTZ 1Aa and WDS 19535 + 2405 = DJU 4, the orbits have been calculated before and here improved orbital elements are presented. The reason is that recent measurements show higher residuals with respect to the corresponding ephemerides calculated by using the earlier orbital elements given in the Sixth Catalog of Orbits of Visual Binary Stars. As for the fourth binary, WDS 07106 + 1543 = J 703, this is the first orbit obtained for it. Out of these four binaries two have short periods and small separations so that it has been possible to resolve them by using interferometric measurements only; the other two have large periods. The ephemerides are presented for all the four stars, whereas the total masses and mass estimates for the components, determined by using trigonometric parallaxes and spectral types, are presented for three of them only (J 703 is exception).

  8. Periodic orbits of hybrid systems and parameter estimation via AD.

    Energy Technology Data Exchange (ETDEWEB)

    Guckenheimer, John. (Cornell University); Phipps, Eric Todd; Casey, Richard (INRIA Sophia-Antipolis)

    2004-07-01

    Rhythmic, periodic processes are ubiquitous in biological systems; for example, the heart beat, walking, circadian rhythms and the menstrual cycle. Modeling these processes with high fidelity as periodic orbits of dynamical systems is challenging because: (1) (most) nonlinear differential equations can only be solved numerically; (2) accurate computation requires solving boundary value problems; (3) many problems and solutions are only piecewise smooth; (4) many problems require solving differential-algebraic equations; (5) sensitivity information for parameter dependence of solutions requires solving variational equations; and (6) truncation errors in numerical integration degrade performance of optimization methods for parameter estimation. In addition, mathematical models of biological processes frequently contain many poorly-known parameters, and the problems associated with this impedes the construction of detailed, high-fidelity models. Modelers are often faced with the difficult problem of using simulations of a nonlinear model, with complex dynamics and many parameters, to match experimental data. Improved computational tools for exploring parameter space and fitting models to data are clearly needed. This paper describes techniques for computing periodic orbits in systems of hybrid differential-algebraic equations and parameter estimation methods for fitting these orbits to data. These techniques make extensive use of automatic differentiation to accurately and efficiently evaluate derivatives for time integration, parameter sensitivities, root finding and optimization. The boundary value problem representing a periodic orbit in a hybrid system of differential algebraic equations is discretized via multiple-shooting using a high-degree Taylor series integration method [GM00, Phi03]. Numerical solutions to the shooting equations are then estimated by a Newton process yielding an approximate periodic orbit. A metric is defined for computing the distance

  9. Entanglement entropy converges to classical entropy around periodic orbits

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, Curtis T., E-mail: ca2621@columbia.edu [Department of Physics, Columbia University, 538 West 120th Street, New York, NY 10027 (United States); Berenstein, David, E-mail: dberens@physics.ucsb.edu [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

    2016-03-15

    We consider oscillators evolving subject to a periodic driving force that dynamically entangles them, and argue that this gives the linearized evolution around periodic orbits in a general chaotic Hamiltonian dynamical system. We show that the entanglement entropy, after tracing over half of the oscillators, generically asymptotes to linear growth at a rate given by the sum of the positive Lyapunov exponents of the system. These exponents give a classical entropy growth rate, in the sense of Kolmogorov, Sinai and Pesin. We also calculate the dependence of this entropy on linear mixtures of the oscillator Hilbert-space factors, to investigate the dependence of the entanglement entropy on the choice of coarse graining. We find that for almost all choices the asymptotic growth rate is the same.

  10. Riemann zeros and periodic orbit quantization by harmonic inversion

    CERN Document Server

    Main, J; Wunner, G; Taylor, H S

    1997-01-01

    In formal analogy with Gutzwiller's semiclassical trace formula, the density of zeros of the Riemann zeta function zeta(z=1/2-iw) can be written as a non-convergent series rho(w)=-pi^{-1} sum_p sum_{m=1}^infty ln(p)p^{-m/2} cos(wm ln(p)) with p running over the prime numbers. We obtain zeros and poles of the zeta function by harmonic inversion of the time signal which is a Fourier transform of rho(w). More than 2500 zeros have been calculated to about 12 digit precision as eigenvalues of small matrices using the method of filter-diagonalization. Due to formal analogy of the zeta function with Gutzwiller's periodic orbit trace formula, the method can be applied to the latter to accurately calculate individual semiclassical eigenenergies and resonance poles for classically chaotic systems. The periodic orbit quantization is demonstrated on the three disk scattering system as a physical example.

  11. On the existence of periodic orbits for the fixed homogeneous circle problem

    OpenAIRE

    Azevêdo, C.; Ontaneda, P.

    2007-01-01

    We prove the existence of some types of periodic orbits for a particle moving in Euclidean three-space under the influence of the gravitational force induced by a fixed homogeneous circle. These types include periodic orbits very far and very near the homogeneous circle, as well as eight and spiral periodic orbits.

  12. Periodic local MP2 method employing orbital specific virtuals

    Energy Technology Data Exchange (ETDEWEB)

    Usvyat, Denis, E-mail: denis.usvyat@chemie.uni-regensburg.de; Schütz, Martin, E-mail: martin.schuetz@chemie.uni-regensburg.de [Institute for Physical and Theoretical Chemistry, Universität Regensburg, Universitätsstraße 31, D-93040 Regensburg (Germany); Maschio, Lorenzo, E-mail: lorenzo.maschio@unito.it [Dipartimento di Chimica, and Centre of Excellence NIS (Nanostructured Interfaces and Surfaces), Università di Torino, via Giuria 5, I-10125 Torino (Italy)

    2015-09-14

    We introduce orbital specific virtuals (OSVs) to represent the truncated pair-specific virtual space in periodic local Møller-Plesset perturbation theory of second order (LMP2). The OSVs are constructed by diagonalization of the LMP2 amplitude matrices which correspond to diagonal Wannier-function (WF) pairs. Only a subset of these OSVs is adopted for the subsequent OSV-LMP2 calculation, namely, those with largest contribution to the diagonal pair correlation energy and with the accumulated value of these contributions reaching a certain accuracy. The virtual space for a general (non diagonal) pair is spanned by the union of the two OSV sets related to the individual WFs of the pair. In the periodic LMP2 method, the diagonal LMP2 amplitude matrices needed for the construction of the OSVs are calculated in the basis of projected atomic orbitals (PAOs), employing very large PAO domains. It turns out that the OSVs are excellent to describe short range correlation, yet less appropriate for long range van der Waals correlation. In order to compensate for this bias towards short range correlation, we augment the virtual space spanned by the OSVs by the most diffuse PAOs of the corresponding minimal PAO domain. The Fock and overlap matrices in OSV basis are constructed in the reciprocal space. The 4-index electron repulsion integrals are calculated by local density fitting and, for distant pairs, via multipole approximation. New procedures for determining the fit-domains and the distant-pair lists, leading to higher efficiency in the 4-index integral evaluation, have been implemented. Generally, and in contrast to our previous PAO based periodic LMP2 method, the OSV-LMP2 method does not require anymore great care in the specification of the individual domains (to get a balanced description when calculating energy differences) and is in that sense a black box procedure. Discontinuities in potential energy surfaces, which may occur for PAO-based calculations if one is not

  13. Computing unstable manifolds of periodic orbits in delay differential equations

    CERN Document Server

    Krauskopf, B

    2003-01-01

    We present the first algorithm for computing unstable manifolds of saddle-type periodic orbits with one unstable Floquet multiplier in systems of autonomous delay differential equations (DDEs) with one fixed delay. Specifically, we grow the one-dimensional unstable manifold W sup u (q) of an associated saddle fixed point q of a Poincare map defined by a suitable Poincare section SIGMA. Starting close to q along the linear approximation to W sup u (q) given by the associated eigenfunction, our algorithm grows the manifold as a sequence of points, where the distance between points is governed by the curvature of the one-dimensional intersection curve W sup u (q intersection SIGMA of W sup u (q) with SIGMA. Our algorithm makes it possible to study global bifurcations in DDEs. We illustrate this with the break-up of an invariant torus and a subsequent crisis bifurcation to chaos in a DDE model of a semiconductor laser with phase-conjugate feedback.

  14. Spin-orbit coupling in periodically driven optical lattices

    Science.gov (United States)

    Struck, Julian; Simonet, Juliette; Sengstock, Klaus

    2015-05-01

    The realization of artificial spin-orbit coupling (SOC) for the external degrees of freedom of neutral, ultracold atoms has raised considerable interest in recent years. It has been predicted that the interplay between interactions and SOC leads to a variety of many-body phases, ranging from stripe states to topological superfluids. Currently, a main experimental obstacle in the realization of these phases is the limited lifetime of the atomic ensemble. All of the experimentally implemented schemes rely on the near-resonant Raman coupling of internal states and thus suffer from the spontaneous emission of photons, leading to excitations and particle loss. Here we present a novel method for the emulation of artificial SOC for atoms trapped in a tight-binding lattice. This scheme does not involve near-resonant laser fields, avoiding the heating processes connected to spontaneous emission. In our case, the necessary spin-dependent tunnel matrix elements are generated by a rapid, spin-dependent, periodic force, which can be described in the framework of an effective, time-averaged Hamiltonian. An additional radio-frequency coupling between the spin states leads to a mixing of the spin bands. The strength of the SOC can be continuously tuned, simply by adjusting the driving amplitude.

  15. Resummation of classical and semiclassical periodic orbit formulas

    CERN Document Server

    Eckhardt, B; Eckhardt, Bruno; Russberg, Gunnar

    1993-01-01

    Abstract: The convergence properties of cycle expanded periodic orbit expressions for the spectra of classical and semiclassical time evolution operators have been studied for the open three disk billiard. We present evidence that both the classical and the semiclassical Selberg zeta function have poles. Applying a Padé approximation on the expansions of the full Euler products, as well as on the individual dynamical zeta functions in the products, we calculate the leading poles and the zeros of the improved expansions with the first few poles removed. The removal of poles tends to change the simple linear exponential convergence of the Selberg zeta functions to an $\\exp\\{-n^{3/2}\\}$ decay in the classical case and to an $\\exp\\{-n^2\\}$ decay in the semiclassical case. The leading poles of the $j$th dynamical zeta function are found to equal the leading zeros of the $j+1$th one: However, in contrast to the zeros, which are all simple, the poles seem without exception to be {\\em double}\\/. The poles are theref...

  16. Noise destroys the coexistence of periodic orbits of a piecewise linear map

    Science.gov (United States)

    Wang, Can-Jun; Yang, Ke-Li; Qu, Shi-Xian

    2013-03-01

    The effects of Gaussian white noise and Gaussian colored noise on the periodic orbits of period-5 (P-5) and period-6 (P-6) in their coexisting domain of a piecewise linear map are investigated numerically. The probability densities of some orbits are calculated. When the noise intensity is D = 0.0001, only the orbits of P-5 exist, and the coexisting phenomenon is destroyed. On the other hand, the self-correlation time τ of the colored noise also affects the coexisting phenomenon. When τc τ'c (τc and τc' are critical values), only the orbits of P-6 exist, and the stability of the P-6 orbits is enhanced greatly. When τ < τc, the orbits of P-5 and P-6 coexist, but the stability of the P-5 orbits is enhanced and that of P-6 is weakened with τ increasing.

  17. Density of the set of symbolic dynamics with all ergodic measures supported on periodic orbits

    OpenAIRE

    Batista, T. C.; Gonschorowski, J. S.; Tal, F. A.

    2014-01-01

    Let $K$ be the Cantor set. We prove that arbitrarily close to a homeomorphism $T:K\\rightarrow K$ there exists a homeomorphism $\\widetilde T:K\\rightarrow K$ such that the $\\alpha$-limit and the $\\omega$-limit of every orbit is a periodic orbit. We also prove that arbitrarily close to an endomorphism $T:K\\rightarrow K$ there exists an endomorphism $\\widetilde T:K\\rightarrow K$ close to $T$ such that every orbit is finally periodic.

  18. Performance Analysis of BDS Satellite Orbits during Eclipse Periods: Results of Satellite Laser Ranging Validation

    Directory of Open Access Journals (Sweden)

    PENG Hanbing

    2016-06-01

    Full Text Available The performance of BeiDou satellite orbits during eclipse periods is an important part of the performance analysis of BeiDou Navigation Satellite System (BDS. Accuracy evaluation of satellite orbits in ephemeris of BDS during eclipse periods can provide support for the service performance assessment. It also helps to find possible deficiencies in the orbit modeling during eclipse periods, which may further contribute to the improvements of functional models for precise orbit determination. The effects of eclipse periods on the orbits of the three types of satellites of BDS are analyzed with the satellite laser ranging (SLR observations ranging from January 2014 to July 2015. At the same time, the orbit radial accuracy of BDS broadcast and precise ephemeris are validated. The results show that, obvious orbit accuracy decrease can be observed in both broadcast and precise ephemeris for IGSO/MEO satellites during eclipse periods (especially the yaw-maneuver periods. And orbit radial errors of IGSO/MEO satellites in broadcast ephemeris reach 1.5~2.0 m, and exceed 10.0 cm for that in precise ephemeris. Performance decrease of the GEO satellite orbit during eclipse arcs can hardly be revealed by the orbit radial residual series. During non-eclipse periods, radial accuracy of IGSO/MEO and GEO satellite orbits in broadcast ephemeris are better than 0.5 m and 0.9 m respectively. The radial accuracy of IGSO/MEO satellite orbits in precise ephemeris are better than 10.0 cm and that of the GEO satellite is about 50.0 cm with a systematic bias of 40.0 cm around.

  19. Orbits for the Impatient: A Bayesian Rejection-sampling Method for Quickly Fitting the Orbits of Long-period Exoplanets

    Science.gov (United States)

    Blunt, Sarah; Nielsen, Eric L.; De Rosa, Robert J.; Konopacky, Quinn M.; Ryan, Dominic; Wang, Jason J.; Pueyo, Laurent; Rameau, Julien; Marois, Christian; Marchis, Franck; Macintosh, Bruce; Graham, James R.; Duchêne, Gaspard; Schneider, Adam C.

    2017-05-01

    We describe a Bayesian rejection-sampling algorithm designed to efficiently compute posterior distributions of orbital elements for data covering short fractions of long-period exoplanet orbits. Our implementation of this method, Orbits for the Impatient (OFTI), converges up to several orders of magnitude faster than two implementations of Markov Chain Monte Carlo (MCMC) in this regime. We illustrate the efficiency of our approach by showing that OFTI calculates accurate posteriors for all existing astrometry of the exoplanet 51 Eri b up to 100 times faster than a Metropolis-Hastings MCMC. We demonstrate the accuracy of OFTI by comparing our results for several orbiting systems with those of various MCMC implementations, finding the output posteriors to be identical within shot noise. We also describe how our algorithm was used to successfully predict the location of 51 Eri b six months in the future based on less than three months of astrometry. Finally, we apply OFTI to 10 long-period exoplanets and brown dwarfs, all but one of which have been monitored over less than 3% of their orbits, producing fits to their orbits from astrometric records in the literature.

  20. PERIODIC ORBIT FAMILIES IN THE GRAVITATIONAL FIELD OF IRREGULAR-SHAPED BODIES

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Yu [State Key Laboratory of Astronautic Dynamics, Xi’an Satellite Control Center, Xi’an 710043 (China); Baoyin, Hexi, E-mail: jiangyu_xian_china@163.com [School of Aerospace Engineering, Tsinghua University, Beijing 100084 (China)

    2016-11-01

    The discovery of binary and triple asteroids in addition to the execution of space missions to minor celestial bodies in the past several years have focused increasing attention on periodic orbits around irregular-shaped celestial bodies. In the present work, we adopt a polyhedron shape model for providing an accurate representation of irregular-shaped bodies and employ the model to calculate their corresponding gravitational and effective potentials. We also investigate the characteristics of periodic orbit families and the continuation of periodic orbits. We prove a fact, which provides a conserved quantity that permits restricting the number of periodic orbits in a fixed energy curved surface about an irregular-shaped body. The collisions of Floquet multipliers are maintained during the continuation of periodic orbits around the comet 1P/Halley. Multiple bifurcations in the periodic orbit families about irregular-shaped bodies are also discussed. Three bifurcations in the periodic orbit family have been found around the asteroid 216 Kleopatra, which include two real saddle bifurcations and one period-doubling bifurcation.

  1. Periodic orbits and their stability in the Rössler prototype-4 system

    Energy Technology Data Exchange (ETDEWEB)

    García, Isaac A., E-mail: garcia@matematica.udl.cat [Departament de Matemàtica, Universitat de Lleida, Avda. Jaume II, 69, 25001 Lleida, Catalonia (Spain); Llibre, Jaume, E-mail: jllibre@mat.uab.cat [Departament de Matemàtiques, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia (Spain); Maza, Susanna, E-mail: smaza@matematica.udl.cat [Departament de Matemàtica, Universitat de Lleida, Avda. Jaume II, 69, 25001 Lleida, Catalonia (Spain)

    2012-07-02

    For the Rössler prototype-4 system x{sup .}=−y−z, y{sup .}=x, z{sup .}=αy(1−y)−βz we prove the existence of periodic orbits and study their stability or instability. The main tool for proving these results is the averaging theory. Recently the existence of some of these periodic orbits were detected numerically. -- Highlights: ► We deal with the Rössler prototype-4 system x{sup .}=−y−z, y{sup .}=x, z{sup .}=αy(1−y)−βz. ► It is one of the simplest autonomous differential equations exhibiting chaos. ► Recently some periodic orbits for this system has been detected numerically. ► We provide an analytical proof of these orbits and study their stability. ► Also we prove the existence of periodic orbits not detected numerically.

  2. Complex periodic orbits in the rotational spectrum of molecules: The example of SF6

    Science.gov (United States)

    Robbins, Jonathan M.; Creagh, Stephen C.; Littlejohn, Robert G.

    1989-03-01

    Periodic orbit theory expresses, in a semiclassically approximate way, the trace of the energy-dependent Green's function of a quantum-mechanical system in terms of a sum over periodic orbits of the corresponding classical system. In this paper a periodic orbit sum is carried out for a Hamiltonian describing the rotational dynamics of the SF6 molecule. Following Miller [J. Phys. Chem. 83, 960 (1979)], classically forbidden, or ``tunneling'' orbits are included in the sum. A closed-form expression for the trace of the energy-dependent Green's function is obtained; it depends on the actions and Maslov indices of the classical orbits, as well as the irreducible representatives of the generators of the molecular point group. The expression reproduces the rich structure characteristic of the rotational spectra of symmetric molecules, including the exponentially near degeneracies for large angular momentum, and the periodicities in eigenvalue symmetry assignments. The methods used here complement the extensive studies of Harter and Patterson.

  3. Generic Diffeomorphisms with Superexponential Growth of Number of Periodic Orbits

    Science.gov (United States)

    Kaloshin, Vadim Yu.

    Let M be a smooth compact manifold of dimension at least 2 and Diffr(M) be the space of Cr smooth diffeomorphisms of M. Associate to each diffeomorphism f;isin; Diffr(M) the sequence Pn(f) of the number of isolated periodic points for f of period n. In this paper we exhibit an open set N in the space of diffeomorphisms Diffr(M) such for a Baire generic diffeomorphism f∈N the number of periodic points Pnf grows with a period n faster than any following sequence of numbers {an}n∈Z+ along a subsequence, i.e. Pn(f)>ani for some ni-->∞ with i-->∞. In the cases of surface diffeomorphisms, i.e. dim M≡2, an open set N with a supergrowth of the number of periodic points is a Newhouse domain. A proof of the man result is based on the Gontchenko-Shilnikov-Turaev Theorem [GST]. A complete proof of that theorem is also presented.

  4. Periodic-Orbit Bifurcation and Shell Structure in Reflection-Asymmetric Deformed Cavity

    OpenAIRE

    Sugita, A.; Arita, K.; Matsuyanagi, K.

    1997-01-01

    Shell structure of the single-particle spectrum for reflection-asymmetric deformed cavity is investigated. Remarkable shell structure emerges for certain combinations of quadrupole and octupole deformations. Semiclassical periodic-orbit analysis indicates that bifurcation of equatorial orbits plays an important role in the formation of this new shell structure.

  5. The family of Quasi-satellite periodic orbits in the co-planar RTBP

    Science.gov (United States)

    Pousse, Alexandre; Robutel, Philippe; Vienne, Alain

    2015-05-01

    In the framework of the Restricted Three-body Problem (RTBP), we consider a primary whose mass is equal to one, a secondary on circular or eccentric motion with a mass ɛ and a massless third body. The three bodies are in coplanar motion and in co-orbital resonance.We actually know three classes of regular co-orbital motions: in rotating frame with the secondary, the tadpole orbits (TP) librate around Lagrangian equilibria L4 or L5 the horseshoe orbits (HS) encompass the three equilibrium points L3, L4 and L5 the quasi-satellite orbits (QS) are remote retrograde satellite around the secondary, but outside of its Hill sphere.Contrarily to TP orbits which emerge from a fixed point in rotating frame, QS orbits emanate from a one-parameter family of periodic orbits, denoted family-f by Henon (1969). In the averaged problem, this family can be understood as a family of fixed points. However, the eccentricity of these orbits can reach high values. Consequently a development in eccentricity will not be efficient.Using the method developed by Nesvorný et al. (2002) which is valid for every values of eccentricity, we study the QS periodic orbits family with a numerical averaging.In the circular case, I will present the validity domain of the average approximation and a particular orbit. Then, I will highlight an unexpected result for very high eccentricity on families of periodic orbits that originate from L3, L4 and L5. Finally, I will sketch out an analytic method adapted to QS motion and exhibit associated results in the eccentric case.

  6. Scaling of Body Masses and Orbital Periods in the Solar System

    Directory of Open Access Journals (Sweden)

    Müller H.

    2015-04-01

    Full Text Available The paper shows that the sequence of sorted by value body masses of planets and largest planetoids is connected by a constant scaling exponent with the sequence of their sorted by value orbital periods.

  7. Periodic orbits for an infinite family of classical superintegrable systems

    Energy Technology Data Exchange (ETDEWEB)

    Tremblay, Frederick; Winternitz, Pavel [Centre de recherches mathematiques and Departement de mathematiques et de statistique, Universite de Montreal, C.P. 6128, Succ. Centre-Ville, Montreal (QC) H3C 3J7 (Canada); Turbiner, Alexander V [Instituto de Ciencias Nucleares, UNAM, A.P. 70-543, 04510 (Mexico)], E-mail: tremblaf@crm.umontreal.ca, E-mail: wintern@crm.umontreal.ca, E-mail: turbiner@nucleares.unam.mx

    2010-01-08

    We show that all bounded trajectories in the two-dimensional classical system with the potential V(r,{phi})={omega}{sup 2}r{sup 2}+({alpha}k{sup 2})/(r{sup 2}cos{sup 2}k{phi})+({beta}k{sup 2})/(r{sup 2}sin{sup 2}k{phi}) are closed for all integer and rational values of k. The period is T={pi}/2{omega} and does not depend on k. This agrees with our earlier conjecture suggesting that the quantum version of this system is superintegrable.

  8. Hyperbolic periodic orbits in nongradient systems and small-noise-induced metastable transitions

    OpenAIRE

    Tao, Molei

    2016-01-01

    Small noise can induce rare transitions between metastable states, which can be characterized by Maximum Likelihood Paths (MLPs). Nongradient systems contrast gradient systems in that MLP does not have to cross the separatrix at a saddle point, but instead possibly at a point on a hyperbolic periodic orbit. A numerical approach for identifying such unstable periodic orbits is proposed based on String method. In a special class of nongradient systems (`orthogonal-type'), there are provably loc...

  9. Periodic orbit theory for the continuum of general mixed-dynamical systems

    OpenAIRE

    Kaidel, Jörg; Winkler, Peter; Brack, Matthias

    2004-01-01

    We investigate the resonance spectrum of the H\\\\\\'enon-Heiles potential up to twice the barrier energy. The quantum spectrum is obtained by the method of complex coordinate rotation. We use periodic orbit theory to approximate the oscillating part of the resonance spectrum semiclassically and Strutinsky smoothing to obtain its smooth part. Although the system in this energy range is almost chaotic, it still contains stable periodic orbits. Using Gutzwiller\\'s trace formula, complemented by a ...

  10. Coorbital motion in the co-planar RTBP: family of Quasi-satellite periodic orbits

    Science.gov (United States)

    Pousse, A.; Robutel, P.; Vienne, A.

    2015-10-01

    In the framework of the Restricted Three-body Problem (RTBP), we consider a primary whose mass is equal to one, a secondary on circular or eccentric motion with a mass # and a massless third body. The three bodies are in coplanar motion and in co-orbital resonance. We actually know three classes of regular coorbital motions: in rotating frame with the secondary, the tadpole orbits (TP) librate around Lagrangian equilibria L4 or L5; the horseshoe orbits (HS) encompass the three equilibrium points L3, L4 and L5; the quasi-satellite orbits (QS) are remote retrograde satellite around the secondary, but outside of its Hill sphere. Contrarily to TP orbits which emerge from a fixed point in rotating frame, QS orbits emanate from a oneparameter family of periodic orbits, denoted family-f by Henon (1969). In the averaged problem, this family can be understood as a family of fixed points. However, the eccentricity of these orbits can reach high values. Consequently a development in eccentricity will not be efficient. Using the method developed by Nesvorny et al. (2002) which is valid for every values of eccentricity, we study the QS periodic orbits family with a numerical averaging. In the circular case, I will present the validity domain of the average approximation and a particular orbit. Then, I will highlight an unexpected result for very high eccentricity on families of periodic orbits that originate from L3, L4 and L5. Finally, I will sketch out an analytic method adapted to QS motion and exhibit associated results in the eccentric case.

  11. Orbital period variations of the eclipsing binaries TU Cnc, VZ Leo, and OS Ori

    Science.gov (United States)

    Khaliullina, A. I.

    2017-10-01

    Variations of the orbital periods of the eclipsing binaries TU Cnc, VZ Leo, and OS Ori are analyzed. Secular period decreases were earlier believed to occur in these systems. It is demonstrated that the period variations of TU Cnc can be represented using the light-time effect corresponding to the orbital motion of the eclipsing binary with a period of 78.6 years around the center ofmass of the triple system, with the mass of the third body being M 3 > 0.82 M ⊙. With the same accuracy, the period variations of VZ Leo and OS Ori can be represented either solely using the light-time effect, or a superposition of a secular period decrease and the light-time effect. For VZ Leo, the period of the long-term orbit is 63.8 years in the former case and 67.9 years in the latter case. Similar masses for the third body are indicated in both cases: M 3 > 0.55 M ⊙ and M 3 > 0.61 M ⊙. For OS Ori, the period of the long-term orbit is 46 years and M 3 > 0.5 M ⊙ in the former case, and the period is 36 years and M 3 > 0.6 M ⊙ in the latter case.

  12. Orbital stability of periodic traveling-wave solutions for the log-KdV equation

    Science.gov (United States)

    Natali, Fábio; Pastor, Ademir; Cristófani, Fabrício

    2017-09-01

    In this paper we establish the orbital stability of periodic waves related to the logarithmic Korteweg-de Vries equation. Our motivation is inspired in the recent work [3], in which the authors established the well-posedness and the linear stability of Gaussian solitary waves. By using the approach put forward recently in [20] to construct a smooth branch of periodic waves as well as to get the spectral properties of the associated linearized operator, we apply the abstract theories in [13] and [25] to deduce the orbital stability of the periodic traveling waves in the energy space.

  13. An approach for finding long period elliptical orbits for precursor SEI missions

    Science.gov (United States)

    Fraietta, Michael F.; Bond, Victor R.

    1993-01-01

    Precursors for Solar System Exploration Initiative (SEI) missions may require long period elliptical orbits about a planet. These orbits will typically have periods on the order of tens to hundreds of days. Some potential uses for these orbits may include the following: studying the effects of galactic cosmic radiation, parking orbits for engineering and operational test of systems, and ferrying orbits between libration points and low altitude orbits. This report presents an approach that can be used to find these orbits. The approach consists of three major steps. First, it uses a restricted three-body targeting algorithm to determine the initial conditions which satisfy certain desired final conditions in a system of two massive primaries. Then the initial conditions are transformed to an inertial coordinate system for use by a special perturbation method. Finally, using the special perturbation method, other perturbations (e.g., sun third body and solar radiation pressure) can be easily incorporated to determine their effects on the nominal trajectory. An algorithm potentially suitable for on-board guidance will also be discussed. This algorithm uses an analytic method relying on Chebyshev polynomials to compute the desired position and velocity of the satellite as a function of time. Together with navigation updates, this algorithm can be implemented to predict the size and timing for AV corrections.

  14. The orbits of subdwarf-B + main-sequence binaries. III. The period-eccentricity distribution

    Science.gov (United States)

    Vos, J.; Østensen, R. H.; Vučković, M.; Van Winckel, H.

    2017-09-01

    Context. The predicted orbital-period distribution of the subdwarf-B (sdB) population is bi-modal with peaks at short (500 days) periods. Observationally, many short-period sdB systems are known, but only few wide sdB binaries have been studied in detail. Based on a long-term monitoring programme the wide sdB sample has been increased, discovering an unexpected positive correlation between the eccentricity and orbital period. Aims: In this article we present the orbital solution and spectral analysis of four new systems, BD-7°5977, EC 11031-1348, TYC 2084-448-1 and TYC 3871-835-1, and update the orbital solution of PG 1104+243. Using the whole sample of wide sdB binaries, we aim to find possible correlations between orbital and spectral properties. The ultimate goal is to improve theoretical models of Roche-lobe overflow. Methods: High-resolution spectroscopic time series were obtained to determine the RVs of both the sdB and main sequence (MS) components. Literature photometry was used to construct the spectral-energy distributions, which were fitted with atmosphere models to determine the surface gravities and temperatures of both components in all systems. Spectral parameters of the cool companion were verified using the GSSP code. Furthermore the amount of accreted mass was estimated. Results: Orbital parameters matching the earlier observed period-eccentricity relation were found for three systems, while TYC 2084-448-1 is found to have a lower eccentricity than expected from the period-eccentricity trend indicated by the other systems. Based on new observations, the orbit of PG 1104+243 has a small but significant eccentricity of 0.04 ± 0.02, matching that of the other systems with similar periods. Furthermore, a positive correlation between accreted mass and orbital period was found, as well as a possible relation between the initial mass-ratio and the final period-eccentricity. Conclusions: The wide sdB-binary sample shows interesting possible correlations

  15. How can periodic orbits puzzle out the coexistence of terrestrial planets with giant eccentric ones?

    Science.gov (United States)

    Antoniadou, K. I.; Libert, A.-S.

    2017-09-01

    Hitherto unprecedented detections of exoplanets have been triggered by missions and ground based telescopes. The quest of ``exo-Earths'' has become intriguing and the long-term stability of planetary orbits is a crucial factor for the biosphere to evolve. Planets in mean-motion resonances (MMRs) prompt the investigation of the dynamics in the framework of the three-body problem, where the families of stable periodic orbits constitute the backbone of stability domains in phase space. In this talk, we address the question of the possible coexistence of terrestrial planets with a giant companion on circular or eccentric orbit and explore the extent of the stability regions, when both the eccentricity of the outer giant planet and the semi-major axis of the inner terrestrial one vary, i.e. we investigate both non-resonant and resonant configurations. The families of periodic orbits in the restricted three-body problem are computed for the 3/2, 2/1, 5/2, 3/1, 4/1 and 5/1 MMRs. We then construct maps of dynamical stability (DS-maps) to identify the boundaries of the stability domains where such a coexistence is allowed. Guided by the periodic orbits, we delve into regular motion in phase space and propose the essential values of the orbital elements, in order for such configurations to survive long time spans and hence, for observations to be complemented or revised.

  16. About periodic and quasi-periodic orbits of a new type for twist maps of the torus

    Directory of Open Access Journals (Sweden)

    SALVADOR ADDAS-ZANATA

    2002-03-01

    Full Text Available We prove that for a large and important class of C¹ twist maps of the torus periodic and quasi-periodic orbits of a new type exist, provided that there are no rotational invariant circles (R.I.C's. These orbits have a non-zero "vertical rotation number'' (V.R.N., in contrast to what happens to Birkhoff periodic orbits and Aubry-Mather sets. The V.R.N. is rational for a periodic orbit and irrational for a quasi-periodic. We also prove that the existence of an orbit with a V.R.N = a > 0, implies the existence of orbits with V.R.N = b, for all 0 Provamos que para uma relevante classe de aplicações C¹ no toro, que desviam a vertical para a direita, existem órbitas periódicas e quase-periódicas de um novo tipo, se e somente se, não existem círculos rotacionais invariantes. Essas órbitas têm um número de rotação vertical não nulo (N.R.V, em contraste com o que ocorre para órbitas periódicas do tipo Birkhoff e para os conjuntos de Aubry-Mather. O número de rotação vertical é racional para uma órbita periódica e irracional para uma quase-periódica. Também provamos que a existência de uma órbita com N.R.V = a implica a existência de órbitas com N.R.V = b, para todo 0 < b < a. Como consequência destes resultados, obtemos que uma aplicação do toro que desvia a vertical e não possui círculos rotacionais invariates, necessariamente tem entropia topológica positiva, que é um resultado clássico. No fim deste trabalho apresentamos aplicações e exemplos, como o Standard map, dos resultados obtidos.

  17. A new uniqueness criterion for the number of periodic orbits of Abel equations

    Science.gov (United States)

    Álvarez, M. J.; Gasull, A.; Giacomini, H.

    A solution of the Abel equation x˙=A(t)x+B(t)x such that x(0)=x(1) is called a periodic orbit of the equation. Our main result proves that if there exist two real numbers a and b such that the function aA(t)+bB(t) is not identically zero, and does not change sign in [0,1] then the Abel differential equation has at most one non-zero periodic orbit. Furthermore, when this periodic orbit exists, it is hyperbolic. This result extends the known criteria about the Abel equation that only refer to the cases where either A(t)≢0 or B(t)≢0 does not change sign. We apply this new criterion to study the number of periodic solutions of two simple cases of Abel equations: the one where the functions A(t) and B(t) are 1-periodic trigonometric polynomials of degree one and the case where these two functions are polynomials with three monomials. Finally, we give an upper bound for the number of isolated periodic orbits of the general Abel equation x˙=A(t)x+B(t)x+C(t)x, when A(t), B(t) and C(t) satisfy adequate conditions.

  18. Orbital periods of cataclysmic variables identified by the SDSS. VII. Four new eclipsing systems

    Science.gov (United States)

    Southworth, J.; Copperwheat, C. M.; Gänsicke, B. T.; Pyrzas, S.

    2010-02-01

    We present photometry of nine cataclysmic variable stars identified by the Sloan Digital Sky Survey, aimed at measuring the orbital periods of these systems. Four of these objects show deep eclipses, from which we measure their orbital periods. The light curves of three of the eclipsing systems are also analysed using the lcurve code, and their mass ratios and orbital inclinations determined. SDSS J075059.97+141150.1 has an orbital period of 134.1564 ± 0.0008 min, making it a useful object with which to investigate the evolutionary processes of cataclysmic variables. SDSS J092444.48+080150.9 has a period of 131.2432 ± 0.0014 min and is probably magnetic. The white dwarf ingress and egress phases are very deep and short, and there is no clear evidence that this object has an accretion disc. SDSS J115207.00+404947.8 and SDSS J152419.33+220920.1 are nearly identical twins, with periods of 97.5 ± 0.4 and 93.6 ± 0.5 min and mass ratios of 0.14 ± 0.03 and 0.17 ± 0.03, respectively. Their eclipses have well-defined white dwarf and bright spot ingress and egress features, making them excellent candidates for detailed study. All four of the orbital periods presented here are shorter than the 2-3 h period gap observed in the known population of cataclysmic variables. The reduced observational data presented in this work are available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/510/A100 and at http://www.astro.keele.ac.uk/ jkt/.

  19. Modeling and analysis of periodic orbits around a contact binary asteroid

    NARCIS (Netherlands)

    Feng, J.; Noomen, R.; Visser, P.N.A.M.; Yuan, J.

    2015-01-01

    The existence and characteristics of periodic orbits (POs) in the vicinity of a contact binary asteroid are investigated with an averaged spherical harmonics model. A contact binary asteroid consists of two components connected to each other, resulting in a highly bifurcated shape. Here, it is

  20. Periodic orbits in the restricted three-body problem and Arnold's J +-invariant

    Science.gov (United States)

    Cieliebak, Kai; Frauenfelder, Urs; van Koert, Otto

    2017-07-01

    We apply Arnold's theory of generic smooth plane curves to Stark-Zeeman systems. This is a class of Hamiltonian dynamical systems that describes the dynamics of an electron in an external electric and magnetic field, and includes many systems from celestial mechanics. Based on Arnold's J +-invariant, we introduce invariants of periodic orbits in planar Stark-Zeeman systems and study their behavior.

  1. Discrete Restricted Four-Body Problem: Existence of Proof of Equilibria and Reproducibility of Periodic Orbits

    Science.gov (United States)

    Minesaki, Yukitaka

    2015-01-01

    We propose the discrete-time restricted four-body problem (d-R4BP), which approximates the orbits of the restricted four-body problem (R4BP). The d-R4BP is given as a special case of the discrete-time chain regularization of the general N-body problem published in Minesaki. Moreover, we analytically prove that the d-R4BP yields the correct orbits corresponding to the elliptic relative equilibrium solutions of the R4BP when the three primaries form an equilateral triangle at any time. Such orbits include the orbit of a relative equilibrium solution already discovered by Baltagiannis and Papadakis. Until the proof in this work, there has been no discrete analog that preserves the orbits of elliptic relative equilibrium solutions in the R4BP. For a long time interval, the d-R4BP can precisely compute some stable periodic orbits in the Sun-Jupiter-Trojan asteroid-spacecraft system that cannot necessarily be reproduced by other generic integrators.

  2. Discrete restricted four-body problem: Existence of proof of equilibria and reproducibility of periodic orbits

    Energy Technology Data Exchange (ETDEWEB)

    Minesaki, Yukitaka [Tokushima Bunri University, Nishihama, Yamashiro-cho, Tokushima 770-8514 (Japan)

    2015-01-01

    We propose the discrete-time restricted four-body problem (d-R4BP), which approximates the orbits of the restricted four-body problem (R4BP). The d-R4BP is given as a special case of the discrete-time chain regularization of the general N-body problem published in Minesaki. Moreover, we analytically prove that the d-R4BP yields the correct orbits corresponding to the elliptic relative equilibrium solutions of the R4BP when the three primaries form an equilateral triangle at any time. Such orbits include the orbit of a relative equilibrium solution already discovered by Baltagiannis and Papadakis. Until the proof in this work, there has been no discrete analog that preserves the orbits of elliptic relative equilibrium solutions in the R4BP. For a long time interval, the d-R4BP can precisely compute some stable periodic orbits in the Sun–Jupiter–Trojan asteroid–spacecraft system that cannot necessarily be reproduced by other generic integrators.

  3. Periodic orbits near bifurcations of codimension two Classical mechanics, semiclassics, and Stokes transitions

    CERN Document Server

    Schomerus, H

    1997-01-01

    We investigate classical and semiclassical aspects of codimension--two bifurcations of periodic orbits in Hamiltonian systems. A classification of these bifurcations in autonomous systems with two degrees of freedom or time-periodic systems with one degree of freedom is presented. We derive uniform approximations to be used in semiclassical trace formulas and determine also certain global bifurcations in conjunction with Stokes transitions that become important in the ensuing diffraction catastrophe integrals.

  4. Periodic orbits for space-based reflectors in the circular restricted three-body problem

    Science.gov (United States)

    Salazar, F. J. T.; McInnes, C. R.; Winter, O. C.

    2017-05-01

    The use of space-based orbital reflectors to increase the total insolation of the Earth has been considered with potential applications in night-side illumination, electric power generation and climate engineering. Previous studies have demonstrated that families of displaced Earth-centered and artificial halo orbits may be generated using continuous propulsion, e.g. solar sails. In this work, a three-body analysis is performed by using the circular restricted three body problem, such that, the space mirror attitude reflects sunlight in the direction of Earth's center, increasing the total insolation. Using the Lindstedt-Poincaré and differential corrector methods, a family of halo orbits at artificial Sun-Earth L_2 points are found. It is shown that the third order approximation does not yield real solutions after the reflector acceleration exceeds 0.245 mm s^{-2}, i.e. the analytical expressions for the in- and out-of-plane amplitudes yield imaginary values. Thus, a larger solar reflector acceleration is required to obtain periodic orbits closer to the Earth. Derived using a two-body approach and applying the differential corrector method, a family of displaced periodic orbits close to the Earth are therefore found, with a solar reflector acceleration of 2.686 mm s^{-2}.

  5. The puzzling orbital period evolution of the LMXB AX J1745.6-2901

    Science.gov (United States)

    Ponti, G.; De, K.; Munoz-Darias, T.; Stella, L.; Nandra, K.

    2017-10-01

    The discovery of gravitational waves through mergers of binary black holes raises the question of how such compact systems form, renewing issues related to the orbital evolution of binary systems. Eclipsing X-ray binaries are excellent tools to constrain the orbital period evolution and how the system loses angular momentum. I will present an X-ray eclipse timing analysis (spanning an interval of more than 20 yr) of one of such objects, AX J1745.6-2901. Its orbital period is decreasing at a rate Pdotorb=-4.03+-0.32 e-11 s s-1, at least one order of magnitude larger than expected from conservative mass transfer and angular momentum losses due to gravitational waves and magnetic braking, and it might result from either non-conservative mass transfer or magnetic activity changing the quadrupole moment of the companion star. I will also show that imprinted on the long-term evolution of the orbit, there are highly significant eclipse leads delays of 10-30 s, characterized by a clear state dependence in which, on average, eclipses occur earlier during the hard state. Finally, I will discuss whether accretion disc winds might have an impact onto the orbital evolution.

  6. Non-linear vibrational modes in biomolecules: A periodic orbits description

    Energy Technology Data Exchange (ETDEWEB)

    Kampanarakis, Alexandros [Department of Chemistry, University of Crete, and Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (FORTH), Vasilika Vouton, Heraklion 71110, Crete (Greece); Farantos, Stavros C., E-mail: farantos@iesl.forth.gr [Department of Chemistry, University of Crete, and Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (FORTH), Vasilika Vouton, Heraklion 71110, Crete (Greece); Daskalakis, Vangelis; Varotsis, Constantinos [Department of Environmental Science and Technology, Cyprus University of Technology, 31 Archbishop Kyprianos St., P.O. Box 50329, 3603 Lemesos (Cyprus)

    2012-05-03

    Graphical abstract: Vibrational frequency shifts in Fe{sup IV} = O species of the active site of cytochrome c oxidase are attributed to changes in the surrounding Coulomb field. Periodic orbits analysis assists to find the most anharmonic modes in model biomolecules. Highlights: Black-Right-Pointing-Pointer Periodic orbits are extended to multidimensional potentials of biomolecules. Black-Right-Pointing-Pointer Highly anharmonic vibrational modes and center-saddle bifurcations are detected. Black-Right-Pointing-Pointer Vibrational frequencies shifts in Oxoferryl species of CcO are observed. - Abstract: The vibrational harmonic normal modes of a molecule, which are valid at energies close to an equilibrium point (a minimum, maximum or saddle of the potential energy surface), are extended by periodic orbits to high energies where anharmonicity and coupling of the degrees of freedom are significant. In this way the assignment of the spectra, and thus the extraction of dynamics in highly excited molecules, can be obtained. New vibrational modes emanating from bifurcations of periodic orbits and long living localized trajectories signal the birth and localization of new quantum states. In this article we review and further study non-linear vibrational modes for model biomolecules such as alanine dipeptide and the active site in the oxoferryl oxidation state of the enzyme cytochrome c oxidase. We locate periodic orbits which exhibit high anhamonicity and lead to center-saddle bifurcations. These modes are associated to an isomerization process in alanine dipeptide and to frequency shifts in the oxoferryl observed by modifying the Coulomb field around the Imidazole-Fe{sup IV} = O species.

  7. Non-Periodic Finite-Element Formulation of Orbital-Free Density Functional Theory

    Energy Technology Data Exchange (ETDEWEB)

    Gavini, V; Knap, J; Bhattacharya, K; Ortiz, M

    2006-10-06

    We propose an approach to perform orbital-free density functional theory calculations in a non-periodic setting using the finite-element method. We consider this a step towards constructing a seamless multi-scale approach for studying defects like vacancies, dislocations and cracks that require quantum mechanical resolution at the core and are sensitive to long range continuum stresses. In this paper, we describe a local real space variational formulation for orbital-free density functional theory, including the electrostatic terms and prove existence results. We prove the convergence of the finite-element approximation including numerical quadratures for our variational formulation. Finally, we demonstrate our method using examples.

  8. The Effect of Seasonal and Long-Period Geopotential Variations on the GPS Orbits

    Science.gov (United States)

    Melachroinos, Stavros A.; Lemoine, Frank G.; Chinn, Douglas S.; Zelensky, Nikita P.; Nicholas, Joseph B.; Beckley, Brian D.

    2013-01-01

    We examine the impact of using seasonal and long-period time-variable gravity field (TVG) models on GPS orbit determination, through simulations from 1994 to 2012. The models of time-variable gravity that we test include the GRGS release RL02 GRACE-derived 10-day gravity field models up to degree and order 20 (grgs20x20), a 4 x 4 series of weekly coefficients using GGM03S as a base derived from SLR and DORIS tracking to 11 satellites (tvg4x4), and a harmonic fit to the above 4 x 4 SLR-DORIS time series (goco2s_fit2). These detailed models are compared to GPS orbit simulations using a reference model (stdtvg) based on the International Earth Rotation Service (IERS) and International GNSS Service (IGS) repro1 standards. We find that the new TVG modeling produces significant along, cross-track orbit differences as well as annual, semi-annual, draconitic and long-period effects in the Helmert translation parameters (Tx, Ty, Tz) of the GPS orbits with magnitudes of several mm. We show that the simplistic TVG modeling approach used by all of the IGS Analysis Centers, which is based on the models provided by the IERS standards, becomes progressively less adequate following 2006 when compared to the seasonal and long-period TVG models.

  9. TRANSITING PLANETS WITH LSST. II. PERIOD DETECTION OF PLANETS ORBITING 1 M{sub ⊙} HOSTS

    Energy Technology Data Exchange (ETDEWEB)

    Jacklin, Savannah [Department of Astrophysics and Planetary Science, Villanova University, Villanova, PA 19085 (United States); Lund, Michael B.; Stassun, Keivan G. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Pepper, Joshua [Department of Physics, Lehigh University, Bethlehem, PA 18015 (United States)

    2015-07-15

    The Large Synoptic Survey Telescope (LSST) will photometrically monitor ∼10{sup 9} stars for 10 years. The resulting light curves can be used to detect transiting exoplanets. In particular, as demonstrated by Lund et al., LSST will probe stellar populations currently undersampled in most exoplanet transit surveys, including out to extragalactic distances. In this paper we test the efficiency of the box-fitting least-squares (BLS) algorithm for accurately recovering the periods of transiting exoplanets using simulated LSST data. We model planets with a range of radii orbiting a solar-mass star at a distance of 7 kpc, with orbital periods ranging from 0.5 to 20 days. We find that standard-cadence LSST observations will be able to reliably recover the periods of Hot Jupiters with periods shorter than ∼3 days; however, it will remain a challenge to confidently distinguish these transiting planets from false positives. At the same time, we find that the LSST deep-drilling cadence is extremely powerful: the BLS algorithm successfully recovers at least 30% of sub-Saturn-size exoplanets with orbital periods as long as 20 days, and a simple BLS power criterion robustly distinguishes ∼98% of these from photometric (i.e., statistical) false positives.

  10. Spin-orbit alignment for 110 day period KOI368.01 from gravity darkening

    Energy Technology Data Exchange (ETDEWEB)

    Ahlers, John P.; Seubert, Shayne A.; Barnes, Jason W. [Department of Physics, University of Idaho, 875 Perimeter Drive Stop 440903, Moscow, ID 83844-0903 (United States)

    2014-05-10

    We fit the Kepler photometric light curve of the KOI-368 system using an oblate, gravity-darkened stellar model in order to constrain its spin-orbit alignment. We find that the system is relatively well-aligned with a sky-projected spin-orbit alignment of λ = 10° ± 2°, a stellar obliquity of ψ = 3° ± 7°, and a true spin-orbit alignment of ψ = 11° ± 3°. Although our measurement differs significantly from zero, the low value for ψ is consistent with spin-orbit alignment. We also measure various transit parameters of the KOI-368 system: R {sub KOI-368} = 2.28 ± 0.02 R {sub ☉}, R{sub p} = 1.83 ± 0.02 R {sub jup}, and i = 89.°221 ± 0.°013. This work shows that our gravity-darkened model can constrain long-period, well-aligned planets and M-class stars orbiting fast-rotators, allowing for measurement of a new subcategory of transiting bodies.

  11. Orbits

    CERN Document Server

    Xu, Guochang

    2008-01-01

    This is the first book of the satellite era which describes orbit theory with analytical solutions of the second order with respect to all possible disturbances. Based on such theory, the algorithms of orbits determination are completely revolutionized.

  12. Orbital period changes in RW CrA, DX Vel and V0646 Cen

    Science.gov (United States)

    Volkov, I. M.; Chochol, D.; Grygar, J.; Mašek, M.; Juryšek, J.

    2017-06-01

    We aim to determine the absolute parameters of the components of southern Algol-type binaries with deep eclipses RW CrA, DX Vel, V0646 Cen and interpret their orbital period changes. The data analysis is based on a high quality Walraven photoelectric photometry, obtained in the 1960-70s, our recent CCD photometry, ASAS (Pojmanski, 2002), and Hipparcos (Perryman et al., 1997) photometry of the objects. Their light curves were analyzed using the PHOEBE program with fixed effective temperatures of the primary components, found from disentangling the Walraven (B-U) and (V-B) colour indices. We found the absolute parameters of the components of all three objects. All reliable observed times of minimum light were used to construct and analyze the Eclipse Time Variation (ETV) diagrams. We interpreted the ETV diagrams of the detached binary RW CrA and the semi-detached binary DX Vel by a LIght-Time Effect (LITE), estimated parameters of their orbits and masses of their third bodies. We suggest a long term variation of the inclination angle of both eclipsing binaries, caused by a non-coplanar orientation of their third body orbits. We interpreted the detected orbital period increase in the semi-detached binary V0646 Cen by a mass transfer from the less to more massive component with the rate M⊙ = 6.08×10-9 M⊙/yr.

  13. Periodic orbits in the restricted four-body problem with two equal masses

    Science.gov (United States)

    Burgos-García, Jaime; Delgado, Joaquín

    2013-06-01

    The restricted (equilateral) four-body problem consists of three bodies of masses m 1, m 2 and m 3 (called primaries) lying in a Lagrangian configuration of the three-body problem i.e., they remain fixed at the apices of an equilateral triangle in a rotating coordinate system. A massless fourth body moves under the Newtonian gravitation law due to the three primaries; as in the restricted three-body problem (R3BP), the fourth mass does not affect the motion of the three primaries. In this paper we explore symmetric periodic orbits of the restricted four-body problem (R4BP) for the case of two equal masses where they satisfy approximately the Routh's critical value. We will classify them in nine families of periodic orbits. We offer an exhaustive study of each family and the stability of each of them.

  14. Cyclic Variations of Orbital Period and Long-Term Luminosity in Close Binary RT Andromedae

    Science.gov (United States)

    Manzoori, Davood

    2009-12-01

    Solutions of standard VR light curves for the eclipsing binary RT And were obtained using the PHOEBE program (ver. 0.3a). Absolute parameters of the stellar components were then determined, enabling them to be positioned on the mass-luminosity diagram. Times of minima data ("O - C curve") were analyzed using the method of Kalimeris et al. A cyclic variation in the orbital period and brightness, with timescales of about 11.89 and 12.50 yr were found, respectively. This is associated with a magnetic activity cycle modulating the orbital period of RT And via the Applegate mechanism. To check the consistency of the Applegate model, we have estimated some related parameters of the RT And system. The calculated parameters were in accordance with those estimated by Applegate for other similar systems, except B, the subsurface magnetic field of which shows a rather high value for RT And.

  15. Decentralized Feedback Controllers for Robust Stabilization of Periodic Orbits of Hybrid Systems: Application to Bipedal Walking.

    Science.gov (United States)

    Hamed, Kaveh Akbari; Gregg, Robert D

    2017-07-01

    This paper presents a systematic algorithm to design time-invariant decentralized feedback controllers to exponentially and robustly stabilize periodic orbits for hybrid dynamical systems against possible uncertainties in discrete-time phases. The algorithm assumes a family of parameterized and decentralized nonlinear controllers to coordinate interconnected hybrid subsystems based on a common phasing variable. The exponential and [Formula: see text] robust stabilization problems of periodic orbits are translated into an iterative sequence of optimization problems involving bilinear and linear matrix inequalities. By investigating the properties of the Poincaré map, some sufficient conditions for the convergence of the iterative algorithm are presented. The power of the algorithm is finally demonstrated through designing a set of robust stabilizing local nonlinear controllers for walking of an underactuated 3D autonomous bipedal robot with 9 degrees of freedom, impact model uncertainties, and a decentralization scheme motivated by amputee locomotion with a transpelvic prosthetic leg.

  16. Continued-fraction expansion of eigenvalues of generalized evolution operators in terms of periodic orbits

    CERN Document Server

    Fujisaka, H; Eckhardt, B; Fujisaka, Hirokazu; Shigematsu, Hideto; Eckhardt, Bruno

    1993-01-01

    Abstract: A new expansion scheme to evaluate the eigenvalues of the generalized evolution operator (Frobenius-Perron operator) $H_{q}$ relevant to the fluctuation spectrum and poles of the order-$q$ power spectrum is proposed. The ``partition function'' is computed in terms of unstable periodic orbits and then used in a finite pole approximation of the continued fraction expansion for the evolution operator. A solvable example is presented and the approximate and exact results are compared; good agreement is found.

  17. A Simple Time Domain Collocation Method to Precisely Search for the Periodic Orbits of Satellite Relative Motion

    OpenAIRE

    Xiaokui Yue; Xuechuan Wang; Honghua Dai

    2014-01-01

    A numerical approach for obtaining periodic orbits of satellite relative motion is proposed, based on using the time domain collocation (TDC) method to search for the periodic solutions of an exact J2 nonlinear relative model. The initial conditions for periodic relative orbits of the Clohessy-Wiltshire (C-W) equations or Tschauner-Hempel (T-H) equations can be refined with this approach to generate nearly bounded orbits. With these orbits, a method based on the least-squares principle is the...

  18. Orbital period variations of two W UMa-type binaries: UY UMa and EF Boo

    Science.gov (United States)

    Yu, Yun-Xia; Zhang, Xu-Dong; Hu, Ke; Xiang, Fu-Yuan

    2017-08-01

    The orbital period variations of two W UMa-type contact binaries, UY UMa and EF Boo, are analyzed by using all available times of light minimum. It is detected that the general trends of their (O - C) curves show an upward parabolic variation, which reveals their continuous period increases at the rates of dP / dt = 2.545 ×10-7 days yr-1 and dP / dt = 2.623 ×10-7 days yr-1 , respectively. Meanwhile, UY UMa also shows a cyclic period variation with a small amplitude of A = 0.0026 days superposed on the long-term increase. Due to their contact configurations, the secular period increases are interpreted as a result of mass transfer from the less massive component to the more massive one. The cyclic period variation of UY UMa may be interpreted in terms of either the magnetic activity or the light time effect.

  19. Families of periodic orbits in the restricted four-body problem

    Science.gov (United States)

    Baltagiannis, A. N.; Papadakis, K. E.

    2011-12-01

    In this paper, families of simple symmetric and non-symmetric periodic orbits in the restricted four-body problem are presented. Three bodies of masses m 1, m 2 and m 3 (primaries) lie always at the apices of an equilateral triangle, while each moves in circle about the center of mass of the system fixed at the origin of the coordinate system. A massless fourth body is moving under the Newtonian gravitational attraction of the primaries. The fourth body does not affect the motion of the three bodies. We investigate the evolution of these families and we study their linear stability in three cases, i.e. when the three primary bodies are equal, when two primaries are equal and finally when we have three unequal masses. Series, with respect to the mass m 3, of critical periodic orbits as well as horizontal and vertical-critical periodic orbits of each family and in any case of the mass parameters are also calculated.

  20. Periodic orbit analysis at the onset of the unstable dimension variability and at the blowout bifurcation.

    Science.gov (United States)

    Pereira, R F; de S Pinto, S E; Viana, R L; Lopes, S R; Grebogi, C

    2007-06-01

    Many chaotic dynamical systems of physical interest present a strong form of nonhyperbolicity called unstable dimension variability (UDV), for which the chaotic invariant set contains periodic orbits possessing different numbers of unstable eigendirections. The onset of UDV is usually related to the loss of transversal stability of an unstable fixed point embedded in the chaotic set. In this paper, we present a new mechanism for the onset of UDV, whereby the period of the unstable orbits losing transversal stability tends to infinity as we approach the onset of UDV. This mechanism is unveiled by means of a periodic orbit analysis of the invariant chaotic attractor for two model dynamical systems with phase spaces of low dimensionality, and seems to depend heavily on the chaotic dynamics in the invariant set. We also described, for these systems, the blowout bifurcation (for which the chaotic set as a whole loses transversal stability) and its relation with the situation where the effects of UDV are the most intense. For the latter point, we found that chaotic trajectories off, but very close to, the invariant set exhibit the same scaling characteristic of the so-called on-off intermittency.

  1. More than six hundred new families of Newtonian periodic planar collisionless three-body orbits

    Science.gov (United States)

    Li, XiaoMing; Liao, ShiJun

    2017-12-01

    The famous three-body problem can be traced back to Isaac Newton in the 1680s. In the 300 years since this "three-body problem" was first recognized, only three families of periodic solutions had been found, until 2013 when Šuvakov and Dmitrašinović [Phys. Rev. Lett. 110, 114301 (2013)] made a breakthrough to numerically find 13 new distinct periodic orbits, which belong to 11 new families of Newtonian planar three-body problem with equal mass and zero angular momentum. In this paper, we numerically obtain 695 families of Newtonian periodic planar collisionless orbits of three-body system with equal mass and zero angular momentum in case of initial conditions with isosceles collinear configuration, including the well-known figure-eight family found by Moore in 1993, the 11 families found by Šuvakov and Dmitrašinović in 2013, and more than 600 new families that have never been reported, to the best of our knowledge. With the definition of the average period T = T/L f, where L f is the length of the so-called "free group element", these 695 families suggest that there should exist the quasi Kepler's third law T* ≈ 2:433 ± 0:075 for the considered case, where T ≈ = T | E|3/2 is the scale-invariant average period and E is its total kinetic and potential energy, respectively. The movies of these 695 periodic orbits in the real space and the corresponding close curves on the "shape sphere" can be found via the website: http://numericaltank.sjtu.edu.cn/three-body/three-body.htm.

  2. A Simple Time Domain Collocation Method to Precisely Search for the Periodic Orbits of Satellite Relative Motion

    Directory of Open Access Journals (Sweden)

    Xiaokui Yue

    2014-01-01

    Full Text Available A numerical approach for obtaining periodic orbits of satellite relative motion is proposed, based on using the time domain collocation (TDC method to search for the periodic solutions of an exact J2 nonlinear relative model. The initial conditions for periodic relative orbits of the Clohessy-Wiltshire (C-W equations or Tschauner-Hempel (T-H equations can be refined with this approach to generate nearly bounded orbits. With these orbits, a method based on the least-squares principle is then proposed to generate projected closed orbit (PCO, which is a reference for the relative motion control. Numerical simulations reveal that the presented TDC searching scheme is effective and simple, and the projected closed orbit is very fuel saving.

  3. Orbital

    OpenAIRE

    Yourshaw, Matthew Stephen

    2017-01-01

    Orbital is a virtual reality gaming experience designed to explore the use of traditional narrative structure to enhance immersion in virtual reality. The story structure of Orbital was developed based on the developmental steps of 'The Hero's Journey,' a narrative pattern identified by Joseph Campbell. Using this standard narrative pattern, Orbital is capable of immersing the player quickly and completely for the entirety of play time. MFA

  4. Reconstruction of chaotic saddles by classification of unstable periodic orbits: Kuramoto-Sivashinsky equation

    Energy Technology Data Exchange (ETDEWEB)

    Saiki, Yoshitaka, E-mail: yoshi.saiki@r.hit-u.ac.jp [Graduate School of Commerce and Management, Hitotsubashi University, Tokyo 186-8601 (Japan); Yamada, Michio [Research Institute for Mathematical Sciences (RIMS), Kyoto University, Kyoto 606-8502 (Japan); Chian, Abraham C.-L. [Paris Observatory, LESIA, CNRS, 92195 Meudon (France); National Institute for Space Research (INPE), P.O. Box 515, São José dos Campos, São Paulo 12227-010 (Brazil); Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), São José dos Campos, São Paulo 12228-900 (Brazil); School of Mathematical Sciences, University of Adelaide, Adelaide SA 5005 (Australia); Department of Biomedical Engineering, George Washington University, Washington, DC 20052 (United States); Miranda, Rodrigo A. [Faculty UnB-Gama, and Plasma Physics Laboratory, Institute of Physics, University of Brasília (UnB), Brasília DF 70910-900 (Brazil); Rempel, Erico L. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), São José dos Campos, São Paulo 12228-900 (Brazil)

    2015-10-15

    The unstable periodic orbits (UPOs) embedded in a chaotic attractor after an attractor merging crisis (MC) are classified into three subsets, and employed to reconstruct chaotic saddles in the Kuramoto-Sivashinsky equation. It is shown that in the post-MC regime, the two chaotic saddles evolved from the two coexisting chaotic attractors before crisis can be reconstructed from the UPOs embedded in the pre-MC chaotic attractors. The reconstruction also involves the detection of the mediating UPO responsible for the crisis, and the UPOs created after crisis that fill the gap regions of the chaotic saddles. We show that the gap UPOs originate from saddle-node, period-doubling, and pitchfork bifurcations inside the periodic windows in the post-MC chaotic region of the bifurcation diagram. The chaotic attractor in the post-MC regime is found to be the closure of gap UPOs.

  5. MAXI J1659-152: the shortest orbital period black-hole binary

    DEFF Research Database (Denmark)

    Kuulkers, E.; Kouveliotou, C.; van der Horst, A. J.

    Following the detection of a bright new X-ray source, MAXI J1659-152, a series of observations was triggered with almost all currently flying high-energy missions. We report here on XMM-Newton, INTEGRAL and RXTE observations during the early phase of the X-ray outburst of this transient black......-hole candidate. We confirm the dipping nature in the X-ray light curves. We find that the dips recur on a period of 2.4139+/-0.0005 hrs, and interpret this as the orbital period of the system. It is thus the shortest period black-hole X-ray binary known to date. Using the various observables, we derive...... the properties of the source. The inclination of the accretion disk with respect to the line of sight is estimated to be 60-75 degrees. The companion star to the black hole is possibly a M5 dwarf star, with a mass and radius of about 0.15 M_sun and 0.23 R_sun, respectively. The system is rather compact (orbital...

  6. Photometric study and orbital period analysis of the W UMa type contact binary VZ Psc

    Science.gov (United States)

    Ma, S.; Li, K.; Li, Q.-C.; Gao, H.-Y.

    2018-02-01

    VZ Psc is a W-type contact binary system with a short period of 0.26125897 days. B, V, Rc and Ic light curves of the eclipsing binary system were obtained by using the 1.0 m reflecting telescope at Weihai Observatory of Shandong University. By collecting 136 times of minimum light, we studied the orbital period change of VZ Psc. A sinusoidal variation was discovered in the O - C diagram, and the amplitude of 0.d0023 and the period of 17.7 year were obtained. This can be caused by Applegate mechanism or light-time effect. Both the mechanisms are suited according to our investigation, but we prefer the latter that the light-time effect due to the presence of a third body results in the cyclic variation. By using the W-D program, we analyzed the four color light curves. Because of the asymmetric light curves and the possible third body, we used the spot mode of W-D program with and without L3. We found that a hot spot on the primary component with the third light leads to the best result. A very high filling factor of 94.4% ± 2.8% and orbit inclination of 53.2° were obtained.

  7. Inhibition of quantum transport due to 'scars' of unstable periodic orbits

    Science.gov (United States)

    Jensen, R. V.; Sanders, M. M.; Saraceno, M.; Sundaram, B.

    1989-01-01

    A new quantum mechanism for the suppression of chaotic ionization of highly excited hydrogen atoms explains the appearance of anomalously stable states in the microwave ionization experiments of Koch et al. A novel phase-space representation of the perturbed wave functions reveals that the inhibition of quantum transport is due to the selective excitation of wave functions that are highly localized near unstable periodic orbits in the chaotic classical phase space. The 'scarred' wave functions provide a new basis for the quantum description of a variety of classically chaotic systems.

  8. Post common envelope binaries from SDSS. XII. The orbital period distribution

    Science.gov (United States)

    Nebot Gómez-Morán, A.; Gänsicke, B. T.; Schreiber, M. R.; Rebassa-Mansergas, A.; Schwope, A. D.; Southworth, J.; Aungwerojwit, A.; Bothe, M.; Davis, P. J.; Kolb, U.; Müller, M.; Papadaki, C.; Pyrzas, S.; Rabitz, A.; Rodríguez-Gil, P.; Schmidtobreick, L.; Schwarz, R.; Tappert, C.; Toloza, O.; Vogel, J.; Zorotovic, M.

    2011-12-01

    Context. The complexity of the common-envelope phase and of magnetic stellar wind braking currently limits our understanding of close binary evolution. Because of their intrinsically simple structure, observational population studies of white dwarf plus main sequence (WDMS) binaries can potentially test theoretical models and constrain their parameters. Aims: The Sloan Digital Sky Survey (SDSS) has provided a large and homogeneously selected sample of WDMS binaries, which we characterise in terms of orbital and stellar parameters. Methods: We have obtained radial velocity information for 385 WDMS binaries from follow-up spectroscopy and for an additional 861 systems from the SDSS subspectra. Radial velocity variations identify 191 of these WDMS binaries as post common-envelope binaries (PCEBs). Orbital periods of 58 PCEBs were subsequently measured, predominantly from time-resolved spectroscopy, bringing the total number of SDSS PCEBs with orbital parameters to 79. Observational biases inherent to this PCEB sample were evaluated through extensive Monte Carlo simulations. Results: We find that 21-24% of all SDSS WDMS binaries have undergone common-envelope evolution, which is in good agreement with published binary population models and high-resolution HST imaging of WDMS binaries unresolved from the ground. The bias-corrected orbital period distribution of PCEBs ranges from 1.9 h to 4.3 d and approximately follows a normal distribution in log (Porb), peaking at ~10.3 h. There is no observational evidence for a significant population of PCEBs with periods in the range of days to weeks. Conclusions: The large and homogeneous sample of SDSS WDMS binaries provides the means to test fundamental predictions of binary population models, hence to observationally constrain the evolution of all close compact binaries. Figures 3-6, Tables 1, 5 and Appendices are only available in electronic form at http://www.aanda.orgFull Tables 3, 4, and 6 are only available at the CDS via

  9. Travelling-wave solutions bifurcating from relative periodic orbits in plane Poiseuille flow

    Science.gov (United States)

    Rawat, Subhandu; Cossu, Carlo; Rincon, François

    2016-06-01

    Travelling-wave solutions are shown to bifurcate from relative periodic orbits in plane Poiseuille flow at Re = 2000 in a saddle-node infinite-period bifurcation. These solutions consist in self-sustaining sinuous quasi-streamwise streaks and quasi-streamwise vortices located in the bulk of the flow. The lower branch travelling-wave solutions evolve into spanwise localized states when the spanwise size Lz of the domain in which they are computed is increased. On the contrary, the upper branch of travelling-wave solutions develops multiple streaks when Lz is increased. Upper-branch travelling-wave solutions can be continued into coherent solutions to the filtered equations used in large-eddy simulations where they represent turbulent coherent large-scale motions.

  10. The role of radial nodes of atomic orbitals for chemical bonding and the periodic table.

    Science.gov (United States)

    Kaupp, Martin

    2007-01-15

    The role of radial nodes, or of their absence, in valence orbitals for chemical bonding and periodic trends is discussed from a unified viewpoint. In particular, we emphasize the special role of the absence of a radial node whenever a shell with angular quantum number l is occupied for the first time (lack of "primogenic repulsion"), as with the 1s, 2p, 3d, and 4f shells. Although the consequences of the very compact 2p shell (e.g. good isovalent hybridization, multiple bonding, high electronegativity, lone-pair repulsion, octet rule) are relatively well known, it seems that some of the aspects of the very compact 3d shell in transition-metal chemistry are less well appreciated, e.g., the often weakened and stretched bonds at equilibrium structure, the frequently colored complexes, and the importance of nondynamical electron-correlation effects in bonding. Copyright (c) 2006 Wiley Periodicals, Inc.

  11. Reliability of unstable periodic orbit based control strategies in biological systems

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Nagender; Singh, Harinder P. [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Hasse, Maria [Institut für Höchstleistungsrechnen, Universität Stuttgart, D-70569 Stuttgart (Germany); Biswal, B. [Cluster Innovation Center, University of Delhi, Delhi 110007 (India); Sri Venkateswara College, University of Delhi, Delhi 110021 (India)

    2015-04-15

    Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry of the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics.

  12. Exceptional points in the elliptical three-disk scatterer using semiclassical periodic orbit quantization

    Science.gov (United States)

    Liebermann, Niklas; Main, Jörg; Wunner, Günter

    2017-05-01

    The three-disk scatterer has served as a paradigm for semiclassical periodic orbit quantization of classical chaotic systems using Gutzwiller's trace formula. It represents an open quantum system, thus leading to spectra of complex eigenenergies. An interesting general feature of open quantum systems described by non-Hermitian operators is the possible existence of exceptional points where not only the complex eigenvalues but also their respective eigenvectors coincide. Using Gutzwiller's periodic orbit theory we show that exceptional points exist in a three-disk scatterer if the system's geometry is modified by extending the system from circular to elliptical disks. The extension is implemented in such a way that the system's characteristic C3{v} symmetry is preserved. The two-dimensional parameter plane of the system is then spanned by the distance between and the excentricity of the elliptical disks. As typical signatures of exceptional points we observe the permutation of two resonances when an exceptional point is encircled in parameter space, and a non-Lorentzian resonance line shape in the weighted density of states.

  13. Existence of periodic orbits in nonlinear oscillators of Emden–Fowler form

    Energy Technology Data Exchange (ETDEWEB)

    Mancas, Stefan C., E-mail: mancass@erau.edu [Department of Mathematics, Embry–Riddle Aeronautical University, Daytona Beach, FL 32114-3900 (United States); Rosu, Haret C., E-mail: hcr@ipicyt.edu.mx [IPICyT, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la presa San José 2055, Col. Lomas 4a Sección, 78216 San Luis Potosí, SLP (Mexico)

    2016-01-28

    The nonlinear pseudo-oscillator recently tackled by Gadella and Lara is mapped to an Emden–Fowler (EF) equation that is written as an autonomous two-dimensional ODE system for which we provide the phase-space analysis and the parametric solution. Through an invariant transformation we find periodic solutions to a certain class of EF equations that pass an integrability condition. We show that this condition is necessary to have periodic solutions and via the ODE analysis we also find the sufficient condition for periodic orbits. EF equations that do not pass integrability conditions can be made integrable via an invariant transformation which also allows us to construct periodic solutions to them. Two other nonlinear equations, a zero-frequency Ermakov equation and a positive power Emden–Fowler equation, are discussed in the same context. - Highlights: • An invariant transformation is used to find periodic solution of EF equations. • Phase plane study of the EF autonomous two-dimensional ODE system is performed. • Three examples are presented from the standpoint of the phase plane analysis.

  14. Orbital

    Science.gov (United States)

    Hanson, Robert M.

    2003-06-01

    ORBITAL requires the following software, which is available for free download from the Internet: Netscape Navigator, version 4.75 or higher, or Microsoft Internet Explorer, version 5.0 or higher; Chime Plug-in, version compatible with your OS and browser (available from MDL).

  15. VizieR Online Data Catalog: Early-type EBs with intermediate orbital periods (Moe+, 2015)

    Science.gov (United States)

    Moe, M.; Di Stefano, R.

    2017-09-01

    In this study, we select the NB~96000 systems in the OGLE-I catalog (Udalski et al. 2008AcA....58...89U) with mean magnitudes 16.0V-IP) and typical dust reddenings E(V-I)~0.1-0.3 mag toward hot young stars in the LMC (Zaritsky et al. J/AJ/128/1606), these stars have luminosities and surface temperatures that correspond to B-type MS primaries. From this sample, we analyze the 221 systems that were identified as EBs with orbital periods P=20-50 days (Graczyk et al. 2011, J/AcA/61/103). (2 data files).

  16. Intratypic differentiation of polioviruses isolated from suspected cases of poliomyelitis in Brazil during the period of 1990 to 1993

    Directory of Open Access Journals (Sweden)

    A. M. B. de Filippis

    1994-12-01

    Full Text Available This study analyzed 3129 fecal samples derived from 1626 patients with sudden onset acute flaccid paralysis clinically compatible with poliomyelitis. The samples were collected in the period ranging from January 1990 to September 1993 in all regions of Brazil. Among the 1626 cases studied, 196 had isolation of poliovirus. Nevertheless, it was observed that some factors influenced the isolation rate and the intratypic characterization of these polioviruses. No cases of acute flaccid paralysis has been found to be etiologically related with wild polioviruses.

  17. Probing Planet Formation with APOGEE: A Dichotomy in Planet Orbital-Periods and Stellar Metallicities

    Science.gov (United States)

    Wilson, Robert Forrest; Teske, Johanna; Majewski, Steven R.; Cunha, Katia; Smith, Verne; Souto, Diogo; Bender, Chad; Mahadevan, Suvrath; Troup, Nicholas; ALLENDE PRIETO, CARLOS; Stassun, Keivan G.; Skrutskie, Michael; ALMEIDA, ANDRES; Brinkmann, Jonathan; APOGEE

    2018-01-01

    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a near-infrared (1.5-1.7 microns), high resolution (R~22,500), high S/N (>100), spectroscopic survey as part of the Sloan Digital Sky Survey (SDSS). Among the goals of this survey is multi-epoch monitoring of exoplanetary systems discovered by the Kepler mission, resulting in very high S/N (typically a few hundred) observations of Planet-hosting stars. The combined visits and sensitivity of the Sloan 2.5-meter telescope yield stellar parameters for a large number of planet-hosting systems with higher precision (e.g., $\\sigma_{[Fe/H]} earth) exoplanetary systems. In particular, we find that planets with orbital periods P ≤ 8.5 days have statistically more metal-enriched hosts than planets with P > 8.5 days. This dichotomy implies that there may be different formation histories between these two populations. For example, there may be a protoplanetary disk inner-radius (such as the gas co-rotation radius or the dust-sublimation radius) with a metallicity-dependence at the time of planet formation that allows small, rocky planets to either form or migrate closer in to their host star in metal-rich conditions. In addition, based on previous work about the "Evaporation Valley", there is theoretical support that this critical period of 8.5 days may be tied to the bulk composition of the two exoplanet populations.

  18. An efficient algorithm for global periodic orbits generation near irregular-shaped asteroids

    Science.gov (United States)

    Shang, Haibin; Wu, Xiaoyu; Ren, Yuan; Shan, Jinjun

    2017-07-01

    Periodic orbits (POs) play an important role in understanding dynamical behaviors around natural celestial bodies. In this study, an efficient algorithm was presented to generate the global POs around irregular-shaped uniformly rotating asteroids. The algorithm was performed in three steps, namely global search, local refinement, and model continuation. First, a mascon model with a low number of particles and optimized mass distribution was constructed to remodel the exterior gravitational potential of the asteroid. Using this model, a multi-start differential evolution enhanced with a deflection strategy with strong global exploration and bypassing abilities was adopted. This algorithm can be regarded as a search engine to find multiple globally optimal regions in which potential POs were located. This was followed by applying a differential correction to locally refine global search solutions and generate the accurate POs in the mascon model in which an analytical Jacobian matrix was derived to improve convergence. Finally, the concept of numerical model continuation was introduced and used to convert the POs from the mascon model into a high-fidelity polyhedron model by sequentially correcting the initial states. The efficiency of the proposed algorithm was substantiated by computing the global POs around an elongated shoe-shaped asteroid 433 Eros. Various global POs with different topological structures in the configuration space were successfully located. Specifically, the proposed algorithm was generic and could be conveniently extended to explore periodic motions in other gravitational systems.

  19. Periodic orbit quantization of the Sinai billiard in the small scatterer limit

    CERN Document Server

    Dahlqvist, P; Dahlqvist, Per; Vattay, Gabor

    1997-01-01

    We consider the semiclassical quantization of the Sinai billiard for disk radii R small compared to the wave length 2 pi/k. Via the application of the periodic orbit theory of diffraction we derive the semiclassical spectral determinant. The limitations of the derived determinant are studied by comparing it to the exact KKR determinant, which we generalize here for the A_1 subspace. With the help of the Ewald resummation method developed for the full KKR determinant we transfer the complex diffractive determinant to a real form. The real zeros of the determinant are the quantum eigenvalues in semiclassical approximation. The essential parameter is the strength of the scatterer c=J_0(kR)/Y_0(kR). Surprisingly, this can take any value between plus and minus infinity within the range of validity of the diffractive approximation kR <<4. We study the statistics exhibited by spectra for fixed values of c. It is Poissonian for |c|=infinity, provided the disk is placed inside a rectangle whose sides obeys some ...

  20. Substituent effects on the optical properties of naphthalenediimides: A frontier orbital analysis across the periodic table.

    Science.gov (United States)

    Mulder, Joshua R; Guerra, Célia Fonseca; Slootweg, J Chris; Lammertsma, Koop; Bickelhaupt, F Matthias

    2016-01-15

    A comprehensive theoretical treatment is presented for the electronic excitation spectra of ca. 50 different mono-, di-, and tetrasubstituted naphthalenediimides (NDI) using time-dependent density functional theory (TDDFT) at ZORA-CAM-B3LYP/TZ2P//ZORA-BP86/TZ2P with COSMO for simulating the effect of dichloromethane (DCM) solution. The substituents -XHn are from groups 14-17 and rows 2-5 of the periodic table. The lowest dipole-allowed singlet excitation (S0 -S1 ) of the monosubstituted NDIs can be tuned from 3.39 eV for -F to 2.42 eV for -TeH, while the S0 -S2 transition is less sensitive to substitution with energies ranging between 3.67 eV for -CH3 and 3.44 eV for -SbH2 . In the case of NDIs with group-15 and -16 substituents, the optical transitions strongly depend on the extent to which -XHn is planar or pyramidal as well as on the possible formation of intramolecular hydrogen bonds. The accumulative effect of double and quadruple substitution leads in general to increasing bathochromic shifts, but the increased steric hindrance in tetrasubstituted NDIs can lead to deformations that diminish the effectiveness of the substituents. Detailed analyses of the Kohn-Sham orbital electronic structure in monosubstituted NDIs reveal the mesomeric destabilization of the HOMO as the primary cause of the bathochromic shift of the S0-S1 transition. © 2015 Wiley Periodicals, Inc.

  1. Linking long-term planetary N-body simulations with periodic orbits: application to white dwarf pollution

    Science.gov (United States)

    Antoniadou, Kyriaki I.; Veras, Dimitri

    2016-12-01

    Mounting discoveries of debris discs orbiting newly formed stars and white dwarfs (WDs) showcase the importance of modelling the long-term evolution of small bodies in exosystems. WD debris discs are, in particular, thought to form from very long-term (0.1-5.0 Gyr) instability between planets and asteroids. However, the time-consuming nature of N-body integrators which accurately simulate motion over Gyrs necessitates a judicious choice of initial conditions. The analytical tools known as periodic orbits can circumvent the guesswork. Here, we begin a comprehensive analysis directly linking periodic orbits with N-body integration outcomes with an extensive exploration of the planar circular restricted three-body problem (CRTBP) with an outer planet and inner asteroid near or inside of the 2:1 mean motion resonance. We run nearly 1000 focused simulations for the entire age of the Universe (14 Gyr) with initial conditions mapped to the phase space locations surrounding the unstable and stable periodic orbits for that commensurability. In none of our simulations did the planar CRTBP architecture yield a long-time-scale (≳0.25 per cent of the age of the Universe) asteroid-star collision. The pericentre distance of asteroids which survived beyond this time-scale (≈35 Myr) varied by at most about 60 per cent. These results help affirm that collisions occur too quickly to explain WD pollution in the planar CRTBP 2:1 regime, and highlight the need for further periodic orbit studies with the eccentric and inclined TBP architectures and other significant orbital period commensurabilities.

  2. Spooky Suspects

    Science.gov (United States)

    Pacifici, Lara

    2011-01-01

    This activity presents an option for covering biology content while engaging students in an investigation that highlights the spirit of Halloween. Students are engaged in the story line and have fun trying to solve the mystery kidnapping by using science skills to examine the evidence and eliminate some ghoulish suspects. (Contains 1 figure.)

  3. Post-common envelope binaries from SDSS - XVI. Long orbital period systems and the energy budget of common envelope evolution

    Science.gov (United States)

    Rebassa-Mansergas, A.; Zorotovic, M.; Schreiber, M. R.; Gänsicke, B. T.; Southworth, J.; Nebot Gómez-Morán, A.; Tappert, C.; Koester, D.; Pyrzas, S.; Papadaki, C.; Schmidtobreick, L.; Schwope, A.; Toloza, O.

    2012-06-01

    Virtually all close compact binary stars are formed through common envelope (CE) evolution. It is generally accepted that during this crucial evolutionary phase a fraction of the orbital energy is used to expel the envelope. However, it is unclear whether additional sources of energy, such as the recombination energy of the envelope, play an important role. Here we report the discovery of the second and third longest orbital period post-common envelope binaries (PCEBs) containing white dwarf (WD) primaries, i.e. SDSS J121130.94-024954.4 (? d) and SDSS J222108.45+002927.7 (? d), reconstruct their evolutionary history and discuss the implications for the energy budget of CE evolution. We find that, despite their long orbital periods, the evolution of both systems can still be understood without incorporating recombination energy, although at least small contributions of this additional energy seem to be likely. If recombination energy significantly contributes to the ejection of the envelope, more PCEBs with relatively long orbital periods (? d) harbouring massive WDs (?) should exist.

  4. THE FIRST PHOTOMETRIC STUDY AND ORBITAL SOLUTION/PERIOD ANALYSIS OF THE MISCLASSIFIED BINARY SYSTEM V380 CAS

    Energy Technology Data Exchange (ETDEWEB)

    Christopoulou, P.-E.; Papageorgiou, A. [Department of Physics, University of Patras, 26500 Patra (Greece); Kleidis, S. [Helliniki Astronomiki Enosi, Athens (Greece); Tsantilas, S. [Department of Astrophysics, Astronomy and Mechanics, Faculty of Physics, Athens University, Panepistimiopolis, Zografos 15784, Athens (Greece)

    2012-02-15

    We present the first multicolor CCD photometry for the eclipsing binary V380 Cassiopeia (V380 Cas) observed on 34 nights in 2009 and 2010 at the University of Patras Observatory. The PHOEBE program based on the Wilson-Devinney algorithm was used to analyze the first complete BVR{sub c} I{sub c} light curves. It was found that V380 Cas was misclassified and it is a well-detached system consisting of two main-sequence stars. A range of solutions found to give satisfactory fits to the observations is also investigated. The first orbital solution based on the photometric mass ratio q = 1.08 of almost equal temperatures and masses and orbital inclination of i = 86.{sup 0}57 was obtained. In addition, based on all available times of light minima, including 12 new ones, a new orbital period of P = 2.714539884 days is given.

  5. The First Photometric Study and Orbital Solution/Period Analysis of the Misclassified Binary System V380 Cas

    Science.gov (United States)

    Christopoulou, P.-E.; Papageorgiou, A.; Kleidis, S.; Tsantilas, S.

    2012-02-01

    We present the first multicolor CCD photometry for the eclipsing binary V380 Cassiopeia (V380 Cas) observed on 34 nights in 2009 and 2010 at the University of Patras Observatory. The PHOEBE program based on the Wilson-Devinney algorithm was used to analyze the first complete BVRc Ic light curves. It was found that V380 Cas was misclassified and it is a well-detached system consisting of two main-sequence stars. A range of solutions found to give satisfactory fits to the observations is also investigated. The first orbital solution based on the photometric mass ratio q = 1.08 of almost equal temperatures and masses and orbital inclination of i = 86fdg57 was obtained. In addition, based on all available times of light minima, including 12 new ones, a new orbital period of P = 2.714539884 days is given.

  6. Symmetry breaking and bifurcations in the periodic orbit theory. 2. Spheroidal cavity

    CERN Document Server

    Magner, A G; Fedotkin, S N; Matsuyanagi, K

    2002-01-01

    We derive a semiclassical trace formula for the level density of a three-dimensional spheroidal cavity. To overcome the divergences and discontinuities occurring at bifurcation points and in the spherical limit, the trace integrals over the action-angle variables are performed using an improved stationary phase method. The resulting semiclassical level density oscillations and shell energies are in good agreement with quantum-mechanical results. We find that the births of three-dimensional orbits through the bifurcations of planar orbits in the equatorial plane lead to considerable enhancement of the shell effect for superdeformed shapes. (author)

  7. Improved orbits of three periodic comets - Reinmuth 1, Slaughter-Burnham and Kearns-Kwee

    Science.gov (United States)

    Todorovic-Juchniewicz, B.

    The observations during five apparitions of Comet Reinmuth 1, three apparitions of Comet Slaughter-Burnham and three ones of Comet Kearns-Kwee are collected and the orbits of the comets are improved. The following numbers of observations were used when improving the orbits: 59 of Comet Reinmuth 1, 29 of Comet Slaughter-Burnham and 184 of Comet Kearns-Kwee. The nongravitational effects in the motion of comets Reinmuth 1 and Kearns-Kwee were found. The equations of motion of Comet Reinmuth 1 were integrated till 1988 and an ephemeris for its next return was computed.

  8. Analytical and numerical construction of vertical periodic orbits about triangular libration points based on polynomial expansion relations among directions

    Science.gov (United States)

    Qian, Ying-Jing; Yang, Xiao-Dong; Zhai, Guan-Qiao; Zhang, Wei

    2017-08-01

    Innovated by the nonlinear modes concept in the vibrational dynamics, the vertical periodic orbits around the triangular libration points are revisited for the Circular Restricted Three-body Problem. The ζ -component motion is treated as the dominant motion and the ξ and η -component motions are treated as the slave motions. The slave motions are in nature related to the dominant motion through the approximate nonlinear polynomial expansions with respect to the ζ -position and ζ -velocity during the one of the periodic orbital motions. By employing the relations among the three directions, the three-dimensional system can be transferred into one-dimensional problem. Then the approximate three-dimensional vertical periodic solution can be analytically obtained by solving the dominant motion only on ζ -direction. To demonstrate the effectiveness of the proposed method, an accuracy study was carried out to validate the polynomial expansion (PE) method. As one of the applications, the invariant nonlinear relations in polynomial expansion form are used as constraints to obtain numerical solutions by differential correction. The nonlinear relations among the directions provide an alternative point of view to explore the overall dynamics of periodic orbits around libration points with general rules.

  9. Unstable Manifolds of Relative Periodic Orbits in the Symmetry-Reduced State Space of the Kuramoto-Sivashinsky System

    Science.gov (United States)

    Budanur, Nazmi Burak; Cvitanović, Predrag

    2017-05-01

    Systems such as fluid flows in channels and pipes or the complex Ginzburg-Landau system, defined over periodic domains, exhibit both continuous symmetries, translational and rotational, as well as discrete symmetries under spatial reflections or complex conjugation. The simplest, and very common symmetry of this type is the equivariance of the defining equations under the orthogonal group O(2). We formulate a novel symmetry reduction scheme for such systems by combining the method of slices with invariant polynomial methods, and show how it works by applying it to the Kuramoto-Sivashinsky system in one spatial dimension. As an example, we track a relative periodic orbit through a sequence of bifurcations to the onset of chaos. Within the symmetry-reduced state space we are able to compute and visualize the unstable manifolds of relative periodic orbits, their torus bifurcations, a transition to chaos via torus breakdown, and heteroclinic connections between various relative periodic orbits. It would be very hard to carry through such analysis in the full state space, without a symmetry reduction such as the one we present here.

  10. Characterizing classical periodic orbits from quantum Green's functions in two-dimensional integrable systems: Harmonic oscillators and quantum billiards.

    Science.gov (United States)

    Chen, Y F; Tung, J C; Tuan, P H; Yu, Y T; Liang, H C; Huang, K F

    2017-01-01

    A general method is developed to characterize the family of classical periodic orbits from the quantum Green's function for the two-dimensional (2D) integrable systems. A decomposing formula related to the beta function is derived to link the quantum Green's function with the individual classical periodic orbits. The practicality of the developed formula is demonstrated by numerically analyzing the 2D commensurate harmonic oscillators and integrable quantum billiards. Numerical analyses reveal that the emergence of the classical features in quantum Green's functions principally comes from the superposition of the degenerate states for 2D harmonic oscillators. On the other hand, the damping factor in quantum Green's functions plays a critical role to display the classical features in mesoscopic regime for integrable quantum billiards, where the physical function of the damping factor is to lead to the coherent superposition of the nearly degenerate eigenstates.

  11. Bifurcations of relative periodic orbits in NLS/GP with a triple-well potential

    Science.gov (United States)

    Goodman, Roy H.

    2017-11-01

    The nonlinear Schrödinger/Gross-Pitaevskii (NLS/GP) equation is considered in the presence of three equally-spaced potentials. The problem is reduced to a finite-dimensional Hamiltonian system by a Galerkin truncation. Families of oscillatory orbits are sought in the neighborhoods of the system's nine branches of standing wave solutions. Normal forms are computed in the neighborhood of these branches' various Hamiltonian Hopf and saddle-node bifurcations, showing how the oscillatory orbits change as a parameter is increased. Numerical experiments show agreement between normal form theory and numerical solutions to the reduced system and NLS/GP near the Hamiltonian Hopf bifurcations and some subtle disagreements near the saddle-node bifurcations due to exponentially small terms in the asymptotics.

  12. Tandem Swift and INTEGRAL Data to Revisit the Orbital and Superorbital Periods of 1E 1740.7-2942

    Science.gov (United States)

    Stecchini, Paulo Eduardo; Castro, Manuel; Jablonski, Francisco; D'Amico, Flavio; Braga, João

    2017-07-01

    The black hole candidate 1E 1740.7-2942 is one of the strongest hard X-ray sources in the Galactic Center region. No counterparts in longer wavelengths have been identified for this object yet. The presence of characteristic timing signatures in the flux history of X-ray sources has been shown to be an important diagnostic tool for the properties of these systems. Using simultaneous data from NASA’s Swift and ESA’s INTEGRAL missions, we have found two periodic signatures at 12.61 ± 0.06 days and 171.1 ± 3.0 days in long-term hard X-ray light curves of 1E 1740.7-2942. We interpret those as the orbital and superorbital periods of the object, respectively. The reported orbital period is in good agreement with previous studies of 1E 1740.7-2942 using NASA’s RXTE data. We present here the first firm evidence of a superorbital period for 1E 1740.7-2942, which has important implications for the nature of the binary system.

  13. On the Dynamics of a Model with Coexistence of Three Attractors: A Point, a Periodic Orbit and a Strange Attractor

    Energy Technology Data Exchange (ETDEWEB)

    Llibre, Jaume, E-mail: jllibre@mat.uab.cat [Universitat Autònoma de Barcelona, Departament de Matemàtiques (Spain); Valls, Claudia, E-mail: cvalls@math.ist.utl.pt [Universidade de Lisboa, Departamento de Matemática, Instituto Superior Técnico (Portugal)

    2017-06-15

    For a dynamical system described by a set of autonomous differential equations, an attractor can be either a point, or a periodic orbit, or even a strange attractor. Recently a new chaotic system with only one parameter has been presented where besides a point attractor and a chaotic attractor, it also has a coexisting attractor limit cycle which makes evident the complexity of such a system. We study using analytic tools the dynamics of such system. We describe its global dynamics near the infinity, and prove that it has no Darboux first integrals.

  14. Electronic orbital response of regular extended and infinite periodic systems to magnetic fields. I. Theoretical foundations for static case

    Science.gov (United States)

    Springborg, Michael; Molayem, Mohammad; Kirtman, Bernard

    2017-09-01

    A theoretical treatment for the orbital response of an infinite, periodic system to a static, homogeneous, magnetic field is presented. It is assumed that the system of interest has an energy gap separating occupied and unoccupied orbitals and a zero Chern number. In contrast to earlier studies, we do not utilize a perturbation expansion, although we do assume the field is sufficiently weak that the occurrence of Landau levels can be ignored. The theory is developed by analyzing results for large, finite systems and also by comparing with the analogous treatment of an electrostatic field. The resulting many-electron Hamilton operator is forced to be hermitian, but hermiticity is not preserved, in general, for the subsequently derived single-particle operators that determine the electronic orbitals. However, we demonstrate that when focusing on the canonical solutions to the single-particle equations, hermiticity is preserved. The issue of gauge-origin dependence of approximate solutions is addressed. Our approach is compared with several previously proposed treatments, whereby limitations in some of the latter are identified.

  15. Electronic orbital response of regular extended and infinite periodic systems to magnetic fields. I. Theoretical foundations for static case.

    Science.gov (United States)

    Springborg, Michael; Molayem, Mohammad; Kirtman, Bernard

    2017-09-14

    A theoretical treatment for the orbital response of an infinite, periodic system to a static, homogeneous, magnetic field is presented. It is assumed that the system of interest has an energy gap separating occupied and unoccupied orbitals and a zero Chern number. In contrast to earlier studies, we do not utilize a perturbation expansion, although we do assume the field is sufficiently weak that the occurrence of Landau levels can be ignored. The theory is developed by analyzing results for large, finite systems and also by comparing with the analogous treatment of an electrostatic field. The resulting many-electron Hamilton operator is forced to be hermitian, but hermiticity is not preserved, in general, for the subsequently derived single-particle operators that determine the electronic orbitals. However, we demonstrate that when focusing on the canonical solutions to the single-particle equations, hermiticity is preserved. The issue of gauge-origin dependence of approximate solutions is addressed. Our approach is compared with several previously proposed treatments, whereby limitations in some of the latter are identified.

  16. BOKS 45906: a CV with an Orbital Period of 56.6 Min in the Kepler Field?

    Science.gov (United States)

    Ramsay, Gavin; Howell, Steve B.; Wood, Matt A.; Smale, Alan; Barclay, Thomas; Seebode, Sally A.; Gelino, Dawn; Still, Martin; Cannizzo, John K.

    2013-01-01

    BOKS 45906 was found to be a blue source in the Burrell-Optical-Kepler Survey which showed a 3 magnitude outburst lasting approximately 5 days. We present the Kepler light curve of this source which covers nearly 3 years. We find that it is in a faint optical state for approximately half the time and shows a series of outbursts separated by distinct dips in flux. Using data with 1 minute sampling, we find clear evidence that in its low state BOKS 45906 shows a flux variability on a period of 56.5574 plus or minus 0.0014 minutes and a semi-amplitude of approximately 3 percent. Since we can phase all the 1 minute cadence data on a common ephemeris using this period, it is probable that 56.56 minutes is the binary orbital period. Optical spectra of BOKS 45906 show the presence of Balmer lines in emission indicating it is not an AM CVn (pure Helium) binary. Swift data show that it is a weak X-ray source and is weakly detected in the bluest of the UVOT filters. We conclude that BOKS 45906 is a cataclysmic variable with a period shorter than the 'period-bounce' systems and therefore BOKS 45906 could be the first helium-rich cataclysmic variable detected in the Kepler field.

  17. An orbital period of 0.94 days for the hot-Jupiter planet WASP-18b.

    Science.gov (United States)

    Hellier, Coel; Anderson, D R; Cameron, A Collier; Gillon, M; Hebb, L; Maxted, P F L; Queloz, D; Smalley, B; Triaud, A H M J; West, R G; Wilson, D M; Bentley, S J; Enoch, B; Horne, K; Irwin, J; Lister, T A; Mayor, M; Parley, N; Pepe, F; Pollacco, D L; Segransan, D; Udry, S; Wheatley, P J

    2009-08-27

    The 'hot Jupiters' that abound in lists of known extrasolar planets are thought to have formed far from their host stars, but migrate inwards through interactions with the proto-planetary disk from which they were born, or by an alternative mechanism such as planet-planet scattering. The hot Jupiters closest to their parent stars, at orbital distances of only approximately 0.02 astronomical units, have strong tidal interactions, and systems such as OGLE-TR-56 have been suggested as tests of tidal dissipation theory. Here we report the discovery of planet WASP-18b with an orbital period of 0.94 days and a mass of ten Jupiter masses (10 M(Jup)), resulting in a tidal interaction an order of magnitude stronger than that of planet OGLE-TR-56b. Under the assumption that the tidal-dissipation parameter Q of the host star is of the order of 10(6), as measured for Solar System bodies and binary stars and as often applied to extrasolar planets, WASP-18b will be spiralling inwards on a timescale less than a thousandth that of the lifetime of its host star. Therefore either WASP-18 is in a rare, exceptionally short-lived state, or the tidal dissipation in this system (and possibly other hot-Jupiter systems) must be much weaker than in the Solar System.

  18. Orbit period modulation for relative motion using continuous low thrust in the two-body and restricted three-body problems

    Science.gov (United States)

    Arnot, C. S.; McInnes, C. R.; McKay, R. J.; Macdonald, M.; Biggs, J.

    2018-02-01

    This paper presents rich new families of relative orbits for spacecraft formation flight generated through the application of continuous thrust with only minimal intervention into the dynamics of the problem. Such simplicity facilitates implementation for small, low-cost spacecraft with only position state feedback, and yet permits interesting and novel relative orbits in both two- and three-body systems with potential future applications in space-based interferometry, hyperspectral sensing, and on-orbit inspection. Position feedback is used to modify the natural frequencies of the linearised relative dynamics through direct manipulation of the system eigenvalues, producing new families of stable relative orbits. Specifically, in the Hill-Clohessy-Wiltshire frame, simple adaptations of the linearised dynamics are used to produce a circular relative orbit, frequency-modulated out-of-plane motion, and a novel doubly periodic cylindrical relative trajectory for the purposes of on-orbit inspection. Within the circular restricted three-body problem, a similar minimal approach with position feedback is used to generate new families of stable, frequency-modulated relative orbits in the vicinity of a Lagrange point, culminating in the derivation of the gain requirements for synchronisation of the in-plane and out-of-plane frequencies to yield a singly periodic tilted elliptical relative orbit with potential use as a Lunar far-side communications relay. The Δ v requirements for the cylindrical relative orbit and singly periodic Lagrange point orbit are analysed, and it is shown that these requirements are modest and feasible for existing low-thrust propulsion technology.

  19. V346 Centauri: Early-type eclipsing binary with apsidal motion and abrupt change of orbital period

    Science.gov (United States)

    Mayer, Pavel; Harmanec, Petr; Wolf, Marek; Nemravová, Jana; Prša, Andrej; Frémat, Yves; Zejda, Miloslav; Liška, Jiři; Juryšek, Jakub; Hoňková, Kateřina; Mašek, Martin

    2016-06-01

    New physical elements of the early B-type eclipsing binary V346 Cen are derived using the HARPS spectra downloaded from the ESO archive and also numerous photometric observations from various sources. A model of the observed times of primary and secondary minima that fits them best is a combination of the apsidal motion and an abrupt decrease in the orbital period from 6.^d322123 to 6.^d321843 (shortening by 24 s), which occurred somewhere around JD 2 439 000. Assumption of a secularly decreasing orbital period provides a significantly worse fit. Local times of minima and the final solution of the light curve were obtained with the program PHOEBE. Radial velocities of both binary components, free of line blending, were derived via 2D cross-correlation with a program built on the principles of the program TODCOR. The oxygen lines in the secondary spectra are weaker than those in the model spectra of solar chemical composition. Using the component spectra disentangled with the program KOREL, we find that both components rotate considerably faster than would correspond to the synchronization at periastron. The apside rotation known from earlier studies is confirmed and compared to the theoretical value. Based on observations made with the ESO telescopes at the La Silla Paranal Observatory under programmes ID 083.D-0040(A), 085.C-0614(A), and 178.D-0361(B).Tables A.2-A.6 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/591/A129

  20. THE CALIFORNIA PLANET SURVEY IV: A PLANET ORBITING THE GIANT STAR HD 145934 AND UPDATES TO SEVEN SYSTEMS WITH LONG-PERIOD PLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Katherina Feng, Y.; Wright, Jason T.; Nelson, Benjamin; Wang, Sharon X.; Ford, Eric B. [Center for Exoplanets and Habitable Worlds, Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Marcy, Geoffrey W.; Isaacson, Howard [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Howard, Andrew W., E-mail: astrowright@gmail.com [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2015-02-10

    We present an update to seven stars with long-period planets or planetary candidates using new and archival radial velocities from Keck-HIRES and literature velocities from other telescopes. Our updated analysis better constrains orbital parameters for these planets, four of which are known multi-planet systems. HD 24040 b and HD 183263 c are super-Jupiters with circular orbits and periods longer than 8 yr. We present a previously unseen linear trend in the residuals of HD 66428 indicative of an additional planetary companion. We confirm that GJ 849 is a multi-planet system and find a good orbital solution for the c component: it is a 1 M {sub Jup} planet in a 15 yr orbit (the longest known for a planet orbiting an M dwarf). We update the HD 74156 double-planet system. We also announce the detection of HD 145934 b, a 2 M {sub Jup} planet in a 7.5 yr orbit around a giant star. Two of our stars, HD 187123 and HD 217107, at present host the only known examples of systems comprising a hot Jupiter and a planet with a well constrained period greater than 5 yr, and with no evidence of giant planets in between. Our enlargement and improvement of long-period planet parameters will aid future analysis of origins, diversity, and evolution of planetary systems.

  1. SWIFT REVEALS A ∼5.7 DAY SUPER-ORBITAL PERIOD IN THE M31 GLOBULAR CLUSTER X-RAY BINARY XB158

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, R.; Garcia, M. R.; Murray, S. S. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2015-03-01

    The M31 globular cluster X-ray binary XB158 (a.k.a. Bo 158) exhibits intensity dips on a 2.78 hr period in some observations, but not others. The short period suggests a low mass ratio, and an asymmetric, precessing disk due to additional tidal torques from the donor star since the disk crosses the 3:1 resonance. Previous theoretical three-dimensional smoothed particle hydrodynamical modeling suggested a super-orbital disk precession period 29 ± 1 times the orbital period, i.e., ∼81 ± 3 hr. We conducted a Swift monitoring campaign of 30 observations over ∼1 month in order to search for evidence of such a super-orbital period. Fitting the 0.3-10 keV Swift X-Ray Telescope luminosity light curve with a sinusoid yielded a period of 5.65 ± 0.05 days, and a >5σ improvement in χ{sup 2} over the best fit constant intensity model. A Lomb-Scargle periodogram revealed that periods of 5.4-5.8 days were detected at a >3σ level, with a peak at 5.6 days. We consider this strong evidence for a 5.65 day super-orbital period, ∼70% longer than the predicted period. The 0.3-10 keV luminosity varied by a factor of ∼5, consistent with variations seen in long-term monitoring from Chandra. We conclude that other X-ray binaries exhibiting similar long-term behavior are likely to also be X-ray binaries with low mass ratios and super-orbital periods.

  2. Detecting unstable periodic orbits of nonlinear mappings by a novel quantum-behaved particle swarm optimization non-Lyapunov way

    Energy Technology Data Exchange (ETDEWEB)

    Gao Fei [Department of Mathematics, School of Science, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070 (China); Department of Electrical Engineering and Computer Science, Korean Advanced Institute of Science and Technology, 335 Gwahangno (373-1 Guseong-dong), Yuseong-gu, Daejeon 305-701 (Korea, Republic of)], E-mail: hgaofei@gmail.com; Gao Hongrui [Department of Mathematics, School of Science, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070 (China)], E-mail: gaohr-2009@163.com; Li Zhuoqiu [Department of Mathematics, School of Science, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070 (China)], E-mail: science@whut.edu.cn; Tong Hengqing [Department of Mathematics, School of Science, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070 (China)], E-mail: tonghengqing@126.com; Lee, Ju-Jang [Department of Electrical Engineering and Computer Science, Korean Advanced Institute of Science and Technology, 335 Gwahangno (373-1 Guseong-dong), Yuseong-gu, Daejeon 305-701 (Korea, Republic of)], E-mail: jjlee@ee.kaist.ac.kr

    2009-11-30

    It is well known that set of unstable periodic orbits (UPOs) can be thought of as the skeleton for the dynamics. However, detecting UPOs of nonlinear map is one of the most challenging problems of nonlinear science in both numerical computations and experimental measures. In this paper, a new method is proposed to detect the UPOs in a non-Lyapunov way. Firstly three special techniques are added to quantum-behaved particle swarm optimization (QPSO), a novel mbest particle, contracting the searching space self-adaptively and boundaries restriction (NCB), then the new method NCB-QPSO is proposed. It can maintain an effective search mechanism with fine equilibrium between exploitation and exploration. Secondly, the problems of detecting the UPOs are converted into a non-negative functions' minimization through a proper translation in a non-Lyapunov way. Thirdly the simulations to 6 benchmark optimization problems and different high order UPOs of 5 classic nonlinear maps are done by the proposed method. And the results show that NCB-QPSO is a successful method in detecting the UPOs, and it has the advantages of fast convergence, high precision and robustness.

  3. Controllable all-fiber generation/conversion of circularly polarized orbital angular momentum beams using long period fiber gratings

    Science.gov (United States)

    Han, Ya; Liu, Yan-Ge; Wang, Zhi; Huang, Wei; Chen, Lei; Zhang, Hong-Wei; Yang, Kang

    2018-01-01

    Mode-division multiplexing (MDM) is a promising technology for increasing the data-carrying capacity of a single few-mode optical fiber. The flexible mode manipulation would be highly desired in a robust MDM network. Recently, orbital angular momentum (OAM) modes have received wide attention as a new spatial mode basis. In this paper, we firstly proposed a long period fiber grating (LPFG) system to realize mode conversions between the higher order LP core modes in four-mode fiber. Based on the proposed system, we, for the first time, demonstrate the controllable all-fiber generation and conversion of the higher order LP core modes to the first and second order circularly polarized OAM beams with all the combinations of spin and OAM. Therefore, the proposed LPFG system can be potentially used as a controllable higher order OAM beam switch and a physical layer of the translating protocol from the conventional LP modes communication to the OAM modes communication in the future mode carrier telecommunication system and light calculation protocols.

  4. Characteristics of persistent spin current components in a quasi-periodic Fibonacci ring with spin–orbit interactions: Prediction of spin–orbit coupling and on-site energy

    Energy Technology Data Exchange (ETDEWEB)

    Patra, Moumita; Maiti, Santanu K., E-mail: santanu.maiti@isical.ac.in

    2016-12-15

    In the present work we investigate the behavior of all three components of persistent spin current in a quasi-periodic Fibonacci ring subjected to Rashba and Dresselhaus spin–orbit interactions. Analogous to persistent charge current in a conducting ring where electrons gain a Berry phase in presence of magnetic flux, spin Berry phase is associated during the motion of electrons in presence of a spin–orbit field which is responsible for the generation of spin current. The interplay between two spin–orbit fields along with quasi-periodic Fibonacci sequence on persistent spin current is described elaborately, and from our analysis, we can estimate the strength of any one of two spin–orbit couplings together with on-site energy, provided the other is known. - Highlights: • Determination of Rashba and Dresselhaus spin–orbit fields is discussed. • Characteristics of all three components of spin current are explored. • Possibility of estimating on-site energy is given. • Results can be generalized to any lattice models.

  5. Role of s-p orbital mixing in the bonding and properties of second-period diatomic molecules

    NARCIS (Netherlands)

    Bickelhaupt, F.M.; Nagle, J.K.; Klemm, W.L.

    2008-01-01

    Qualitative molecular orbital theory is widely used as a conceptual tool to understand chemical bonding. Symmetry-allowed orbital mixing between atomic or fragment orbitais of different energies can greatly complicate such qualitative interpretations of chemical bonding. We use high-level Amsterdam

  6. The Role of s�p Orbital Mixing in the Bonding of Second-Period Diatomic Molecules

    NARCIS (Netherlands)

    Bickelhaupt, F.M.; Nagle, J.K.; Klemm, W.L.

    2008-01-01

    Qualitative molecular orbital theory is widely used as a conceptual tool to understand chemical bonding. Symmetry-allowed orbital mixing between atomic or fragment orbitais of different energies can greatly complicate such qualitative interpretations of chemical bonding. We use high-level Amsterdam

  7. The ELODIE survey for northern extra-solar planets II. A Jovian planet on a long-period orbit around GJ 777 A

    OpenAIRE

    Naef, D.; Mayor, M.; Korzennik, S. G.; Queloz, D.; Udry, S.; Nisenson, P.; Noyes, R. W.; Brown, T. M.; Beuzit, J. L.; Perrier, C.; Sivan, J. P.

    2003-01-01

    We present radial-velocity measurements obtained with the ELODIE and AFOE spectrographs for GJ 777 A (HD 190360), a metal-rich ([Fe/H]=0.25) nearby (d=15.9 pc) star in a stellar binary system. A long-period low radial-velocity amplitude variation is detected revealing the presence of a Jovian planetary companion. Some of the orbital elements remain weakly constrained because of the smallness of the signal compared to our instrumental precision. The detailed orbital shape is therefore not well...

  8. Long-period orbital climate forcing. Cyclostratigraphic studies of Cenozoic continental and marine successions in Europe. Geologica Ultraiectina (297)

    NARCIS (Netherlands)

    Abels, H.A.|info:eu-repo/dai/nl/304848018

    2008-01-01

    Orbital climate forcing is well-known for its strong impact on Earth’s climate as for example the switching from glacial to inter-glacial states in the Late Pleistocene. Typical ‘Milankovitch’ cycles are climatic precession (21.000 years or 21 kyrs), obliquity (41 kyrs), and short and long

  9. Angular momentum and topological dependence of Kepler's Third Law in the Broucke-Hadjidemetriou-H\\'enon family of periodic three-body orbits

    CERN Document Server

    Janković, Marija R

    2016-01-01

    We use 57 recently found topological satellites of Broucke-Hadjidemetriou-Henon's periodic orbits with values of the topological exponent $k$ ranging from $k$ = 3 to $k$ = 58 to plot the angular momentum $L$ as a function of the period $T$, with both $L$ and $T$ rescaled to energy $E=-\\frac12$. Upon plotting $L(T/k)$ we find that all our solutions fall on a curve that is virtually indiscernible by naked eye from the $L(T)$ curve for non-satellite solutions. The standard deviation of the satellite data from the sixth-order polynomial fit to the progenitor data is $\\sigma = 0.13$. This regularity supports Henon's 1976 conjecture that the linearly stable Broucke-Hadjidemetriou-Henon orbits are also perpetually, or Kolmogorov-Arnold-Moser stable.

  10. The formation of low-mass helium white dwarfs orbiting pulsars . Evolution of low-mass X-ray binaries below the bifurcation period

    Science.gov (United States)

    Istrate, A. G.; Tauris, T. M.; Langer, N.

    2014-11-01

    Context. Millisecond pulsars (MSPs) are generally believed to be old neutron stars (NSs) that have been spun up to high rotation rates via accretion of matter from a companion star in a low-mass X-ray binary (LMXB). This scenario has been strongly supported by various pieces of observational evidence. However, many details of this recycling scenario remain to be understood. Aims: Here we investigate binary evolution in close LMXBs to study the formation of radio MSPs with low-mass helium white dwarf companions (He WDs) in tight binaries with orbital periods Porb ≃ 2-9h. In particular, we examine i) if the observed systems can be reproduced by theoretical modelling using standard prescriptions of orbital angular momentum losses (i.e. with respect to the nature and the strength of magnetic braking), ii) if our computations of the Roche-lobe detachments can match the observed orbital periods, and iii) if the correlation between WD mass and orbital period (MWD, Porb) is valid for systems with Porb< 2 days. Methods: Numerical calculations with a detailed stellar evolution code were used to trace the mass-transfer phase in ~400 close LMXB systems with different initial values of donor star mass, NS mass, orbital period, and the so-called γ-index of magnetic braking. Subsequently, we followed the orbital and the interior evolution of the detached low-mass (proto) He WDs, including stages with residual shell hydrogen burning. Results: We find that severe fine-tuning is necessary to reproduce the observed MSPs in tight binaries with He WD companions of mass <0.20 M⊙, which suggests that something needs to be modified or is missing in the standard input physics of LMXB modelling. Results from previous independent studies support this conclusion. We demonstrate that the theoretically calculated (MWD, Porb)-relation is in general also valid for systems with Porb< 2 days, although with a large scatter in He WD masses between 0.15-0.20 M⊙. The results of the thermal

  11. Alternative Transfers to the NEOs 99942 Apophis, 1994 WR12, and 2007 UW1 via Derived Trajectories from Periodic Orbits of Family G

    Directory of Open Access Journals (Sweden)

    C. F. de Melo

    2009-01-01

    Full Text Available Swing-by techniques are extensively used in interplanetary missions to minimize fuel consumption and to raise payloads of spacecrafts. The effectiveness of this type of maneuver has been proven since the beginning of space exploration. According to this premise, we have explored the existence of a natural and direct link between low Earth orbits and the lunar sphere of influence to get low-energy transfer trajectories to the Near Earth Objects (NEOs 99942 Apophis, 1994 WR12, and 2007 UW1 through swing-bys with the Moon. The existence of this link is related to a family of retrograde periodic orbits around the Lagrangian equilibrium point L1 predicted for the circular, planar, restricted three-body Earth-Moon-particle problem. The trajectories in this link are sensitive to small disturbances. This enables them to be conveniently diverted reducing so the cost of the swing-by maneuver. These maneuvers allow a gain in energy sufficient for the trajectories to escape from the Earth-Moon system and to stabilize in heliocentric orbits between the Earth and Venus or Earth and Mars. Therefore, the trajectories have sufficient reach to intercept the NEOs' orbits.

  12. The Ceres gravity field, spin pole, rotation period and orbit from the Dawn radiometric tracking and optical data

    Science.gov (United States)

    Konopliv, A. S.; Park, R. S.; Vaughan, A. T.; Bills, B. G.; Asmar, S. W.; Ermakov, A. I.; Rambaux, N.; Raymond, C. A.; Castillo-Rogez, J. C.; Russell, C. T.; Smith, D. E.; Zuber, M. T.

    2018-01-01

    Ceres' gravity field and rotational parameters have been precisely measured using 1.5 years of radiometric Doppler and range data and optical landmark tracking from the Dawn spacecraft in orbit about the dwarf planet. As was the case with Dawn at Vesta, the gravity field, orientation parameters, landmark locations, and Ceres' orbit are jointly estimated in a global solution. Even though Dawn's radio science investigation at Ceres was complicated by additional thrusting for attitude control, the resulting spherical harmonic gravity field has a half-wavelength resolution of up to 82 km (degree 18) near the equator, which is similar harmonic resolution to that of Vesta. The gravity field is consistent with Airy isostatic compensation, and this model assumption limits Ceres' crustal density to be between 1200 and 1600 kg/m3 for two-layer and three-layer models with mean crustal thickness between 27 and 43 km. The compensation depth is determined using admittance between gravity and gravity from topography and is superior to admittance between gravity and topography. The gravitational mass of Ceres is determined to better than 0.002% (GMCeres = 62.62736 ± 0.00040 km3/s2), the spin pole location is improved by 10× over previous results with right ascension (α = 291.427°) and declination (δ = 66.760°) uncertainty less than 0.001°, and the rotation rate is improved by ∼100× over previous determinations from Hubble Space Telescope (HST) images. Ceres' heliocentric orbit has also been improved, with about 17 months of precision range measurements reducing ephemeris uncertainties to about 10 m during the Dawn timeframe.

  13. Photometric, Spectroscopic, and Orbital Period Study of Three Early-type Semi-detached Systems: XZ Aql, UX Her, and AT Peg

    Science.gov (United States)

    Zola, S.; Baştürk, Ö.; Liakos, A.; Gazeas, K.; Şenavcı, H. V.; Nelson, R. H.; Özavcı, İ.; Zakrzewski, B.; Yılmaz, M.

    2016-08-01

    In this paper, we present a combined photometric, spectroscopic, and orbital period study of three early-type eclipsing binary systems: XZ Aql, UX Her, and AT Peg. As a result, we have derived the absolute parameters of their components and, on that basis, we discuss their evolutionary states. Furthermore, we compare their parameters with those of other binary systems and with theoretical models. An analysis of all available up-to-date times of minima indicated that all three systems studied here show cyclic orbital changes; their origin is discussed in detail. Finally, we performed a frequency analysis for possible pulsational behavior, and as a result we suggest that XZ Aql hosts a δ Scuti component.

  14. Regional climate and vegetation response to orbital forcing within the mid-Pliocene Warm Period: A study using HadCM3

    Science.gov (United States)

    Prescott, C. L.; Dolan, A. M.; Haywood, A. M.; Hunter, S. J.; Tindall, J. C.

    2018-02-01

    Regional climate and environmental variability in response to orbital forcing during interglacial events within the mid-Piacenzian (Pliocene) Warm Period (mPWP; 3.264-3.025 Ma) has been rarely studied using climate and vegetation models. Here we use climate and vegetation model simulations to predict changes in regional vegetation patterns in response to orbital forcing for four different interglacial events within the mPWP (Marine Isotope Stages (MIS) G17, K1, KM3 and KM5c). The efficacy of model-predicted changes in regional vegetation is assessed by reference to selected high temporal resolution palaeobotanical studies that are theoretically capable of discerning vegetation patterns for the selected interglacial stages. Annual mean surface air temperatures for the studied interglacials are between 0.4 °C to 0.7 °C higher than a comparable Pliocene experiment using modern orbital parameters. Increased spring/summer and reduced autumn/winter insolation in the Northern Hemisphere during MIS G17, K1 and KM3 enhances seasonality in surface air temperature. The two most robust and notable regional responses to this in vegetation cover occur in North America and continental Eurasia, where forests are replaced by more open-types of vegetation (grasslands and shrubland). In these regions our model results appear to be inconsistent with local palaeobotanical data. The orbitally driven changes in seasonal temperature and precipitation lead to a 30% annual reduction in available deep soil moisture (2.0 m from surface), a critical parameter for forest growth, and subsequent reduction in the geographical coverage of forest-type vegetation; a phenomenon not seen in comparable simulations of Pliocene climate and vegetation run with a modern orbital configuration. Our results demonstrate the importance of examining model performance under a range of realistic orbital forcing scenarios within any defined time interval (e.g. mPWP). Additional orbitally resolved records of

  15. Electronic levels and electrical response of periodic molecular structures from plane-wave orbital-dependent calculations

    Science.gov (United States)

    Li, Yanli; Dabo, Ismaila

    2011-10-01

    Plane-wave electronic-structure predictions based upon orbital-dependent density-functional theory (OD-DFT) approximations, such as hybrid density-functional methods and self-interaction density-functional corrections, are severely affected by computational inaccuracies in evaluating electron interactions in the plane-wave representation. These errors arise from divergence singularities in the plane-wave summation of electrostatic and exchange interaction contributions. Auxiliary-function corrections are reciprocal-space countercharge corrections that cancel plane-wave singularities through the addition of an auxiliary function to the point-charge electrostatic kernel that enters into the expression of interaction terms. At variance with real-space countercharge corrections that are employed in the context of density-functional theory (DFT), reciprocal-space corrections are computationally inexpensive, making them suited to more demanding OD-DFT calculations. Nevertheless, there exists much freedom in the choice of auxiliary functions and various definitions result in different levels of performance in eliminating plane-wave inaccuracies. In this work we derive exact point-charge auxiliary functions for the description of molecular structures of arbitrary translational symmetry, including the yet unaddressed one-dimensional case. In addition, we provide a critical assessment of different reciprocal-space countercharge corrections and demonstrate the improved accuracy of point-charge auxiliary functions in predicting the electronic levels and electrical response of conjugated polymers from plane-wave OD-DFT calculations.

  16. Orbit optimization and time delay interferometry for inclined ASTROD-GW formation with half-year precession-period

    CERN Document Server

    Wang, Gang

    2014-01-01

    ASTROD-GW (ASTROD [Astrodynamical Space Test of Relativity using Optical Devices] optimized for Gravitational Wave detection) is a gravitational-wave mission with the aim of detecting gravitational waves from massive black holes, extreme mass ratio inspirals (EMRIs) and galactic compact binaries, together with testing relativistic gravity and probing dark energy and cosmology. Mission orbits of the 3 spacecrafts forming a nearly equilateral triangular array are chosen to be near the Sun-Earth Lagrange points L3, L4 and L5. The 3 spacecrafts range interferometrically with one another with arm length about 260 million kilometers. For 260 times longer arm length, the detection sensitivity of ASTROD-GW is 260 fold better than that of eLISA/NGO in the lower frequency region by assuming the same acceleration noise. Therefore, ASTROD-GW will be a better cosmological probe. In previous papers, we have worked out the time delay interferometry (TDI) for the ecliptic formation. To resolve the reflection ambiguity about ...

  17. Orbital motion in pre-main sequence binaries

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, G. H. [The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, CA 91023 (United States); Prato, L. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Simon, M. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States); Patience, J., E-mail: schaefer@chara-array.org [Astrophysics Group, School of Physics, University of Exeter, Exeter, EX4 4QL (United Kingdom)

    2014-06-01

    We present results from our ongoing program to map the visual orbits of pre-main sequence (PMS) binaries in the Taurus star forming region using adaptive optics imaging at the Keck Observatory. We combine our results with measurements reported in the literature to analyze the orbital motion for each binary. We present preliminary orbits for DF Tau, T Tau S, ZZ Tau, and the Pleiades binary HBC 351. Seven additional binaries show curvature in their relative motion. Currently, we can place lower limits on the orbital periods for these systems; full solutions will be possible with more orbital coverage. Five other binaries show motion that is indistinguishable from linear motion. We suspect that these systems are bound and might show curvature with additional measurements in the future. The observations reported herein lay critical groundwork toward the goal of measuring precise masses for low-mass PMS stars.

  18. Observation of high-order quasi-one-dimensional periodic orbit resonance in (DMET){sub 2}I{sub 3} and its fermi surface

    Energy Technology Data Exchange (ETDEWEB)

    Oshima, Y.; Kimata, M.; Kishigi, K.; Ohta, H.; Koyama, K.; Motokawa, M.; Nishikawa, H.; Kikuchi, K.; Ikemoto, I

    2004-04-30

    Magneto-optical measurements of a quasi-one-dimensional (q1D) organic superconductor (DMET){sub 2}I{sub 3} has been performed by using a cavity perturbation technique. Several resonant absorption lines, which can be attributed to the q1D periodic orbit resonance (q1D POR), as well as the quite unusual high-order q1D POR coming from the corrugated Fermi surface (FS) in the interlayer direction were observed. Moreover, other harmonic resonances are also observed when the AC electric field is applied along the c*-axis. We will also show its estimated q1D FS from the data analysis where the estimated FS clearly shows why there is no spin-density-wave or charge-density-wave transition in (DMET){sub 2}I{sub 3} despite having a q1D FS.

  19. The OmegaWhite Survey for Short-period Variable Stars. V. Discovery of an Ultracompact Hot Subdwarf Binary with a Compact Companion in a 44-minute Orbit

    Science.gov (United States)

    Kupfer, T.; Ramsay, G.; van Roestel, J.; Brooks, J.; MacFarlane, S. A.; Toma, R.; Groot, P. J.; Woudt, P. A.; Bildsten, L.; Marsh, T. R.; Green, M. J.; Breedt, E.; Kilkenny, D.; Freudenthal, J.; Geier, S.; Heber, U.; Bagnulo, S.; Blagorodnova, N.; Buckley, D. A. H.; Dhillon, V. S.; Kulkarni, S. R.; Lunnan, R.; Prince, T. A.

    2017-12-01

    We report the discovery of the ultracompact hot subdwarf (sdOB) binary OW J074106.0-294811.0 with an orbital period of {P}{orb}=44.66279+/- 1.16× {10}-4 minutes, making it the most compact hot subdwarf binary known. Spectroscopic observations using the VLT, Gemini and Keck telescopes revealed a He-sdOB primary with an intermediate helium abundance, {T}{eff} = 39 400+/- 500 K and {log}g = 5.74 ± 0.09. High signal-to-noise ratio light curves show strong ellipsoidal modulation resulting in a derived sdOB mass {M}{sdOB}=0.23+/- 0.12 {M}⊙ with a WD companion ({M}{WD}=0.72+/- 0.17 {M}⊙ ). The mass ratio was found to be q={M}{sdOB}/{M}{WD}=0.32+/- 0.10. The derived mass for the He-sdOB is inconsistent with the canonical mass for hot subdwarfs of ≈ 0.47 {M}⊙ . To put constraints on the structure and evolutionary history of the sdOB star we compared the derived {T}{eff}, {log}g, and sdOB mass to evolutionary tracks of helium stars and helium white dwarfs calculated with Modules for Experiments in Stellar Astrophysics (MESA). We find that the best-fitting model is a helium white dwarf with a mass of 0.320 {M}⊙ , which left the common envelope ≈ 1.1 {Myr} ago, which is consistent with the observations. As a helium white dwarf with a massive white dwarf companion, the object will reach contact in 17.6 Myr at an orbital period of 5 minutes. Depending on the spin-orbit synchronization timescale the object will either merge to form an R CrB star or end up as a stably accreting AM CVn-type system with a helium white dwarf donor.

  20. Pediatric glaucoma suspects

    Directory of Open Access Journals (Sweden)

    Kooner K

    2014-06-01

    Full Text Available Karanjit Kooner,1 Matthew Harrison,1 Zohra Prasla,1 Mohannad Albdour,1 Beverley Adams-Huet21Department of Ophthalmology, 2Department of Clinical Sciences, Division of Biostatistics, University of Texas Southwestern Medical Center, Dallas, TX, USAPurpose: To report demographic and ocular features of pediatric glaucoma suspects in an ethnically diverse population of North Central Texas.Design: Retrospective cross-sectional chart review.Participants: Subjects included 75 (136 eyes pediatric glaucoma suspects. Patients with one or more of the following risk factors were included: cup-to disc (C/D ratio of ≥0.6; intraocular pressure (IOP ≥21 mmHg; family history of glaucoma; congenital glaucoma in the opposite eye; history of blunt trauma to either eye; and presence of either Sturge–Weber or Axenfeld–Rieger syndrome, or oculodermal melanocytosis.Methods: Data were extracted from electronic patient medical records. Patient records with incomplete data were excluded. The main outcome measures were race, sex, age, IOP, C/D, family history of glaucoma; and glaucoma treatment.Results: Subjects included 28 (37.3% Hispanics, 20 (26.6% African Americans, 20 (26.6% Caucasians, and seven (9.3% Asians. Forty (53.3% of the patients were male. Suspicious optic disc was seen in 57 (76%; elevated IOP in 25 (33.3%; presence of family history in 13 (17.3%, and Sturge–Weber syndrome in nine (12% patients. The average C/D ratio was 0.58±0.2. The C/D ratios of African American (0.65±0.2, Hispanic (0.63±0.2, and Asian (0.62±0.15 patients were significantly greater than those of Caucasians (0.43±0.18; P=0.0004, 0.0003, and 0.0139, respectively. Caucasian patients were the youngest (7.9±4.8 years. Eleven cases (14.7% required medication.Conclusion: Thirty-three point seven percent of patients seen in the glaucoma clinic were glaucoma suspects. The most common risk factors for suspected glaucoma were suspicious optic discs, elevated IOP, and family history

  1. Technology and the Glaucoma Suspect

    National Research Council Canada - National Science Library

    Blumberg, Dana M; De Moraes, Carlos Gustavo; Liebmann, Jeffrey M; Garg, Reena; Chen, Cynthia; Theventhiran, Alex; Hood, Donald C

    2016-01-01

    ...), stereoscopic disc photographs, and automated perimetry as assessed by a group of glaucoma specialists in differentiating individuals with early glaucoma from suspects. Forty-six eyes (46 patients...

  2. Semiclassical description of resonant tunnel effect: bifurcations and periodic orbits in the resonant current; Description semiclassique de l`effet tunnel resonant: bifurcations et orbites periodiques dans le courant resonant

    Energy Technology Data Exchange (ETDEWEB)

    Rouben, D.C

    1997-11-28

    A semiclassical method for resonant tunneling in a quantum well in the presence of a magnetic field tilted with regard to an electric field is developed. In particular a semiclassical formula is derived for the total current of electrons after the second barrier of the quantum well. The contribution of the stable and unstable orbits is studied. It appears that the parameters which describe the classical chaos in the quantum well have an important effect on the tunneling current. A numerical experiment is led, the contributions to the current of some particular orbits are evaluated and the results are compared with those given by the quantum theory. (A.C.) 70 refs.

  3. Suspected poisoning of domestic animals by pesticides.

    Science.gov (United States)

    Caloni, Francesca; Cortinovis, Cristina; Rivolta, Marina; Davanzo, Franca

    2016-01-01

    A retrospective study was carried out by reviewing all suspected cases of domestic animal poisoning attributed to pesticides, reported to the Milan Poison Control Centre (MPCC) between January 2011 and December 2013. During this period, pesticides were found to be responsible for 37.3% of all suspected poisoning enquiries received (815). The most commonly species involved was the dog (71.1% of calls) followed by the cat (15.8%), while a limited number of cases involved horses, goats and sheep. Most cases of exposure (47.1%) resulted in mild to moderate clinical signs. The outcome was reported in 59.9% of these cases, with death occurring in 10.4% of them. Insecticides (40.8%) proved to be the most common group of pesticides involved and exposure to pyrethrins-pyrethroids accounted for the majority of calls. According to the MPCC data, there has been a decrease in the number of suspected poisonings cases attributed to pesticides that have been banned by the EU, including aldicarb, carbofuran, endosulfan and paraquat. In contrast, there has been an increase of suspected poisoning cases attributed to the neonicotinoids, imidacloprid and acetamiprid, probably due to their widespread use in recent years. Cases of suspected poisoning that involved exposure to rodenticides accounted for 27.6% of calls received by the MPCC and anticoagulant rodenticides were the primary cause of calls, with many cases involving brodifacoum and bromadiolone. Herbicides were involved in 14.2% of calls related to pesticides and glyphosate was the main culprit in cases involving dogs, cats, horses, goats and sheep. As far as exposure to molluscicides (11.5%) and fungicides (5.9%), most of the cases involved dogs and the suspected poisoning agents were metaldehyde and copper compounds respectively. The data collected are useful in determining trends in poisoning episodes and identifying newly emerging toxicants, thus demonstrating the prevalence of pesticides as causative agents in animal

  4. Evaluation of Pediatric Patients with Orbital and Preseptal Cellulitis

    Directory of Open Access Journals (Sweden)

    Eren Cagan

    2015-06-01

    Conclusion: Preseptal cellulitis is more frequently observed than orbital cellulitis. The most important predisposing factor for orbital cellulitis is sinusitis. Patients with preseptal cellulitis suspected clinically may be diagnosed with orbital cellulitis radiologically. As a result radiological imaging of preseptal cellulitis patients should be considered. [Cukurova Med J 2015; 40(2.000: 267-274

  5. Small Atomic Orbital Basis Set First-Principles Quantum Chemical Methods for Large Molecular and Periodic Systems: A Critical Analysis of Error Sources.

    Science.gov (United States)

    Sure, Rebecca; Brandenburg, Jan Gerit; Grimme, Stefan

    2016-04-01

    In quantum chemical computations the combination of Hartree-Fock or a density functional theory (DFT) approximation with relatively small atomic orbital basis sets of double-zeta quality is still widely used, for example, in the popular B3LYP/6-31G* approach. In this Review, we critically analyze the two main sources of error in such computations, that is, the basis set superposition error on the one hand and the missing London dispersion interactions on the other. We review various strategies to correct those errors and present exemplary calculations on mainly noncovalently bound systems of widely varying size. Energies and geometries of small dimers, large supramolecular complexes, and molecular crystals are covered. We conclude that it is not justified to rely on fortunate error compensation, as the main inconsistencies can be cured by modern correction schemes which clearly outperform the plain mean-field methods.

  6. [Orbital cellulitis].

    Science.gov (United States)

    Mouriaux, F; Rysanek, B; Babin, E; Cattoir, V

    2012-01-01

    Orbital cellulitis is uncommon in ophthalmologic practice. The majority of cases arise from direct spread of sinus infection or eyelid infection. Clinically, orbital cellulitis is divided into two forms: the preseptal form, anterior to the orbital septum, and the retroseptal form, posterior to the orbital septum. Management and prognosis differ widely between the two types. The retroseptal form or "true" orbital cellulitis is a severe disease with potentially disastrous consequences for vision and survival. Clinical examination and urgent CT scanning are indispensable for correct diagnosis, evaluation of severity, surgical planning and antibiotic selection. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  7. ORBITAL, CELLULITIS

    African Journals Online (AJOL)

    Aim: The purpose of this study was to assess the prevalence of paranasal sinusitis as a cause of orbital cellulitis and to identify the commonest sinus(es) involved in our setting. Methods: A retrospective review of the case notes of 47 patients with orbital cellulitis admitted into the ophthalmic ward of the University College ...

  8. Orbital velocity

    OpenAIRE

    Modestino, Giuseppina

    2016-01-01

    The trajectory and the orbital velocity are determined for an object moving in a gravitational system, in terms of fundamental and independent variables. In particular, considering a path on equipotential line, the elliptical orbit is naturally traced, verifying evidently the keplerian laws. The case of the planets of the solar system is presented.

  9. Orbit Stabilization of Nanosat

    Energy Technology Data Exchange (ETDEWEB)

    JOHNSON,DAVID J.

    1999-12-01

    An algorithm is developed to control a pulsed {Delta}V thruster on a small satellite to allow it to fly in formation with a host satellite undergoing time dependent atmospheric drag deceleration. The algorithm uses four short thrusts per orbit to correct for differences in the average radii of the satellites due to differences in drag and one thrust to symmetrize the orbits. The radial difference between the orbits is the only input to the algorithm. The algorithm automatically stabilizes the orbits after ejection and includes provisions to allow azimuthal positional changes by modifying the drag compensation pulses. The algorithm gives radial and azimuthal deadbands of 50 cm and 3 m for a radial measurement accuracy of {+-} 5 cm and {+-} 60% period variation in the drag coefficient of the host. Approaches to further reduce the deadbands are described. The methodology of establishing a stable orbit after ejection is illustrated in an appendix. The results show the optimum ejection angle to minimize stabilization thrust is upward at 86{sup o} from the orbital velocity. At this angle the stabilization velocity that must be supplied by the thruster is half the ejection velocity. An ejection velocity of 0.02 m/sat 86{sup o} gives an azimuthal separation after ejection and orbit stabilization of 187 m. A description of liquid based gas thrusters suitable for the satellite control is included in an appendix.

  10. THE 2011 ERUPTION OF THE RECURRENT NOVA T PYXIDIS: THE DISCOVERY, THE PRE-ERUPTION RISE, THE PRE-ERUPTION ORBITAL PERIOD, AND THE REASON FOR THE LONG DELAY

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, Bradley E.; Landolt, Arlo U. [Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Linnolt, Michael [American Association of Variable Star Observers, 49 Bay State Road, Cambridge, MA 02138 (United States); Stubbings, Rod [Tetoora Observatory, Tetoora Road, Victoria (Australia); Pojmanski, Grzegorz [Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa (Poland); Plummer, Alan [Variable Stars South, Linden Observatory, 105 Glossop Road, Linden, NSW (Australia); Kerr, Stephen [American Association of Variable Star Observers, Variable Stars South, Astronomical Association of Queensland, 22 Green Avenue, Glenlee, Queensland (Australia); Nelson, Peter [Ellinbank Observatory, 1105 Hazeldean Road, Ellinbank 3821, Victoria (Australia); Carstens, Rolf [American Association of Variable Star Observers, Variable Stars South, CBA, Geyserland Observatory, 120 Homedale Street, Rotorua 3015 (New Zealand); Streamer, Margaret [Lexy' s Palace Observatory, 3 Lupin Place, Murrumbateman, NSW (Australia); Richards, Tom [Variable Stars South, Pretty Hill Observatory, P.O. Box 323, Kangaroo Ground 3097, Victoria (Australia); Myers, Gordon [Center for Backyard Astrophysics, Columbia University, 538 West 120th Street, New York, NY 10027 (United States); Dillon, William G. [American Association of Variable Star Observers, 4703 Birkenhead Circle, Missouri City, TX 77459 (United States)

    2013-08-10

    We report the discovery by M. Linnolt on JD 2,455,665.7931 (UT 2011 April 14.29) of the sixth eruption of the recurrent nova T Pyxidis. This discovery was made just as the initial fast rise was starting, so with fast notification and response by observers worldwide, the entire initial rise was covered (the first for any nova), and with high time resolution in three filters. The speed of the rise peaked at 9 mag day{sup -1}, while the light curve is well fit over only the first two days by a model with a uniformly expanding sphere. We also report the discovery by R. Stubbings of a pre-eruption rise starting 18 days before the eruption, peaking 1.1 mag brighter than its long-time average, and then fading back toward quiescence 4 days before the eruption. This unique and mysterious behavior is only the fourth known (with V1500 Cyg, V533 Her, and T CrB) anticipatory rise closely spaced before a nova eruption. We present 19 timings of photometric minima from 1986 to 2011 February, where the orbital period is fast increasing with P/ P-dot =+313,000 yr. From 2008 to 2011, T Pyx had a small change in this rate of increase, so that the orbital period at the time of eruption was 0.07622950 {+-} 0.00000008 days. This strong and steady increase of the orbital period can only come from mass transfer, for which we calculate a rate of (1.7-3.5) Multiplication-Sign 10{sup -7} M{sub Sun} yr{sup -1}. We report 6116 magnitudes between 1890 and 2011, for an average B = 15.59 {+-} 0.01 from 1967 to 2011, which allows for an eruption in 2011 if the blue flux is nearly proportional to the accretion rate. The ultraviolet-optical-infrared spectral energy distribution is well fit by a power law with f{sub {nu}}{proportional_to}{nu}{sup 1.0}, although the narrow ultraviolet region has a tilt with a fit of f{sub {nu}}{proportional_to}{nu}{sup 1/3}. We prove that most of the T Pyx light is not coming from a disk, or any superposition of blackbodies, but rather is coming from some nonthermal

  11. VERY LOW MASS STELLAR AND SUBSTELLAR COMPANIONS TO SOLAR-LIKE STARS FROM MARVELS. II. A SHORT-PERIOD COMPANION ORBITING AN F STAR WITH EVIDENCE OF A STELLAR TERTIARY AND SIGNIFICANT MUTUAL INCLINATION

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Scott W.; Ge Jian; De Lee, Nathan; Jiang Peng; Lee, Brian; Nelson, Ben [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 2611-2055 (United States); Barnes, Rory [Department of Astronomy, University of Washington, P.O. Box 351580, Seattle, WA 98195 (United States); Beatty, Thomas G.; Gaudi, B. Scott; Shappee, Benjamin J. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Crepp, Justin R. [Department of Astronomy, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125 (United States); Esposito, Massimiliano; Femenia, Bruno; Gonzalez Hernandez, Jonay I. [Instituto de Astrofisica de Canarias (IAC), E-38205 La Laguna, Tenerife (Spain); Ferreira, Leticia; Porto de Mello, Gustavo F. [Observatorio do Valongo, Universidade Federal do Rio de Janeiro, Ladeira do Pedro Antonio, 43, CEP: 20080-090, Rio de Janeiro, RJ (Brazil); Gary, Bruce; Hebb, Leslie; Stassun, Keivan [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Ghezzi, Luan, E-mail: scfleming@psu.edu [Laboratorio Interinstitucional de e-Astronomia, LIneA, Rua Gal. Jose Cristino 77, Rio de Janeiro, RJ-20921-400 (Brazil); and others

    2012-09-15

    We report the discovery via radial velocity (RV) measurements of a short-period (P = 2.430420 {+-} 0.000006 days) companion to the F-type main-sequence star TYC 2930-00872-1. A long-term trend in the RV data also suggests the presence of a tertiary stellar companion with P > 2000 days. High-resolution spectroscopy of the host star yields T{sub eff} = 6427 {+-} 33 K, log g = 4.52 {+-} 0.14, and [Fe/H] = -0.04 {+-} 0.05. These parameters, combined with the broadband spectral energy distribution (SED) and a parallax, allow us to infer a mass and radius of the host star of M{sub 1} = 1.21 {+-} 0.08 M{sub Sun} and R{sub 1} = 1.09{sup +0.15}{sub -0.13} R{sub Sun }. The minimum mass of the inner companion is below the hydrogen-burning limit; however, the true mass is likely to be substantially higher. We are able to exclude transits of the inner companion with high confidence. Further, the host star spectrum exhibits a clear signature of Ca H and K core emission, indicating stellar activity, but a lack of photometric variability and small vsin I suggest that the primary's spin axis is oriented in a pole-on configuration. The rotational period of the primary estimated through an activity-rotation relation matches the orbital period of the inner companion to within 1.5 {sigma}, suggesting that the primary and inner companion are tidally locked. If the inner companion's orbital angular momentum vector is aligned with the stellar spin axis as expected through tidal evolution, then it has a stellar mass of {approx}0.3-0.4 M{sub Sun }. Direct imaging limits the existence of stellar companions to projected separations <30 AU. No set of spectral lines and no significant flux contribution to the SED from either companion are detected, which places individual upper mass limits of M{sub {l_brace}2,3{r_brace}} {approx}< 1.0 M{sub Sun }, provided they are not stellar remnants. If the tertiary is not a stellar remnant, then it likely has a mass of {approx}0.5-0.6 M{sub Sun

  12. An unusual organism causing orbital cellulitis.

    Science.gov (United States)

    Schwartz, H; Baskin, M A; Ilkiw, A; LeBeau, L

    1979-01-01

    Bacterial orbital cellulitis is a feared complication of paranasal sinus infection. Staphylococcus and Streptococcus species are the commoner pathogens involved in these cases. However, anaerobic bacteria and unusual Gram-negative organisms should be suspected as well. We treated a case of bacterial orbital cellulitis due to foci of infected paranasal sinuses caused by Eikenella corrodens, a Gram-negative rod. The patient was managed with intensive antibiotic coverage and surgical intervention. Images PMID:389281

  13. The Hot Orbit: Orbital Cellulitis

    Science.gov (United States)

    Chaudhry, Imtiaz A.; Al-Rashed, Waleed; Arat, Yonca O.

    2012-01-01

    Orbital cellulitis is an uncommon condition previously associated with severe complications. If untreated, orbital cellulitis can be potentially sight and life threatening. It can affect both adults and children but has a greater tendency to occur in the pediatric age group. The infection most commonly originates from sinuses, eyelids or face, retained foreign bodies, or distant soources by hematogenous spread. It is characterized by eyelid edema, erythema, chemosis, proptosis, blurred vision, fever, headache, and double vision. A history of upper respiratory tract infection prior to the onset is very common especially in children. In the era prior to antibiotics, vision loss from orbital cellulitis was a dreaded complication. Currently, imaging studies for detection of orbital abcess, the use of antibiotics and early drainage have mitigated visual morbidity significantly. The purpose of this review is to describe current investigative strategies and management options in the treatment of orbital cellulitis, establish their effectiveness and possible complications due to late intervention. PMID:22346113

  14. New Orbits for 18 Binaries

    Science.gov (United States)

    Cvetković, Z.; Pavlović, R.

    2017-12-01

    Orbital elements of 18 visual binaries are computed using the measurements collected in the Fourth Catalog of Interferometric Measurements of Binary Stars; 15 orbits are determined for the first time and three orbits are revised. Eleven of the binaries, denoted as HDS, were discovered during the Hipparcos mission. The remaining binaries were discovered a few years earlier or later than 1991. All studied pairs are close, and all measured separations are less than 0\\buildrel{\\prime\\prime}\\over{.} 46. The shortest orbital period is 10 years and the longest orbital period is 127 years. Dynamical parallaxes and total masses of systems are derived from the orbital elements. We also give absolute magnitudes, spectral types, and (O-C) residuals in θ and ρ.

  15. Foreign body orbital cyst

    DEFF Research Database (Denmark)

    Yazdanfard, Younes; Heegard, Steffen; Fledelius, Hans C.

    2001-01-01

    Ophthalmology, penetrating orbital injury, orbital foreign body, ultrasound, computed tomography (CT), histology......Ophthalmology, penetrating orbital injury, orbital foreign body, ultrasound, computed tomography (CT), histology...

  16. Orbital Cellulitis Following Orbital Blow-out Fracture.

    Science.gov (United States)

    Byeon, Je Yeon; Choi, Hwan Jun

    2017-10-01

    Orbital cellulitis and abscess have been described in the literature as complication that usually occur secondary to infection in the maxillary, ethmoidal, and frontal sinuses. If left untreated, it can lead to blindness, cavernous sinus thrombosis, meningitis, or cerebral abscess. Orbital fractures are a common sequela of blunt orbital trauma, but are only rarely associated with orbital cellulitis. So, the authors present rare orbital cellulitis after orbital blow-out fracture. A 55-year-old Asian complains of severe orbital swelling and pain on the left side. These symptoms had started 2 days earlier and worsened within the 24 hours before hospital admission resulting in visual disturbances such as diplopia and photophobia. Contrast-enhanced computed tomography scan showed considerable soft tissue swelling and abscess formation on the left side. Patient was subjected to surgical drainage under general anesthesia in the operation room. In this case, the postoperative period was uneventful and the rapid improvement of symptoms was remarkable. In conclusion, the abscess of the orbit is a surgical emergency in patients whose impairment of vision or ocular symptoms cannot be controlled with medical therapy using antibiotics. In our case, orbital cellulitis can occur after blunt orbital trauma without predisposing sinusitis. Early and prompt diagnosis and surgical drainage before severe loss of visual acuity rescue or recover the vision in case of orbital cellulitis.

  17. Suspected levamisole intoxication in calves.

    Science.gov (United States)

    Müller, K R; Dwyer, C

    2016-07-01

    A group of 32 Friesian and four Hereford calves, 3-4 months old with body weights between 100-120 kg, were purchased from a weaner sale. On arrival at the property the Hereford calves were treated with a combination anthelmintic containing 2 g/L abamectin and 80 g/L levamisole hydrochloride. Shortly afterwards they developed tremors and frothing from the mouth, and two died overnight. The Friesian calves were treated with the same anthelmintic on the following day, when some showed hypersalivation and frothing from the mouth. Examination of the three most severely affected Friesian calves revealed severe nicotinic-type symptoms including hypersalivation, frothing from the mouth, muscle tremors, recumbency, rapid respiration, hyperaesthesia, and central nervous system depression. Other calves showed mild to moderate signs of intoxication including restlessness, tail switching, salivation, tremors, frequent defaecation, mild colic and jaw chomping. Two calves died shortly afterwards. An adverse drug event investigation revealed that the formulation and quality of the anthelmintic was within the correct specification, and that the drench gun was functioning correctly. Suspected levamisole intoxication due to a combination of possible overdosing, dehydration, and stress caused by transportation and prolonged yarding. Susceptibility to levamisole toxicity in New Zealand calves can be increased if factors like dehydration or stress are present. Levamisole has a narrow margin of safety, and overdosing in calves can easily occur if the dose rate is not based on their actual weight or health status.

  18. The Eccentric Behavior of Nearly Frozen Orbits

    Science.gov (United States)

    Sweetser, Theodore H.; Vincent, Mark A.

    2013-01-01

    Frozen orbits are orbits which have only short-period changes in their mean eccentricity and argument of periapse, so that they basically keep a fixed orientation within their plane of motion. Nearly frozen orbits are those whose eccentricity and argument of periapse have values close to those of a frozen orbit. We call them "nearly" frozen because their eccentricity vector (a vector whose polar coordinates are eccentricity and argument of periapse) will stay within a bounded distance from the frozen orbit eccentricity vector, circulating around it over time. For highly inclined orbits around the Earth, this distance is effectively constant over time. Furthermore, frozen orbit eccentricity values are low enough that these orbits are essentially eccentric (i.e., off center) circles, so that nearly frozen orbits around Earth are bounded above and below by frozen orbits.

  19. Orbital complications of rhinosinusitis.

    Science.gov (United States)

    Sijuwola, Oo; Adeyemo, Aa; Adeosun, Aa

    2007-06-01

    Suppurative extension of rhinosinusitis to the orbit is a complication that often results from delay in diagnosis and, or inadequate treatment. These complications may range from preseptal cellulitis, orbital cellulitis, orbital abscesses, and subperiosteal abscesses to intracranial extension with a threat to both vision and life. This study aims to review the clinical profile, treatment modalities and outcome of orbital complications of rhinosinusitis in Ibadan, Nigeria. A retrospective review of the charts of patients with orbital complications of rhinosinusitis managed in the departments of Otorhinolaryngology and Ophthalmology, University College Hospital, Ibadan over a five year period (Feb 2002- Jan 2007) was carried out .The diagnosis of rhinosinusitis was based on history, physical examination, plain x ray and CT scan findings and antral puncture. Demographic data, clinical presentation and treatment were evaluated. A total of 24 patients were reviewed in the study. There were 13males and 11females (M/F, 1:1). The age range was 8months to 75years, 14 (58.3%) patients were children and while 10 (41.7%) patients were adults. 75% of the patients were seen during the dry season (November to February). The duration of symptoms ranged from one day to three weeks. Involvement of one eye occurred in 14 patients (58.3%); right eye (4), left eye (10). Both eyes were involved in 10 patients (41.7%). Non-axial proptosis was seen in 8 patients (33.3%). It was infero-lateral in 6 patients (25%) and infero-nasal in two (8.3%) patients. Orbital cellulitis was seen in 10 (41.7%) patients, 6 (25%) patients had preseptal cellulitis while 8 (33%) patients had orbital abscess. Cavernous sinus thrombosis was seen in 3 (12.5%) patients. The cases with preseptal and orbital cellulitis were effectively managed by intravenous antibiotics. Orbital abscesses were drained surgically with complete resolution. Sinus surgical procedures were done in 10(41.7%) patients. This group of

  20. Orbits in weak and strong bars

    CERN Document Server

    Contopoulos, George

    1980-01-01

    The authors study the plane orbits in simple bar models embedded in an axisymmetric background when the bar density is about 1% (weak), 10% (intermediate) or 100% (strong bar) of the axisymmetric density. Most orbits follow the stable periodic orbits. The basic families of periodic orbits are described. In weak bars with two Inner Lindblad Resonances there is a family of stable orbits extending from the center up to the Outer Lindblad Resonance. This family contains the long period orbits near corotation. Other stable families appear between the Inner Lindblad Resonances, outside the Outer Lindblad Resonance, around corotation (short period orbits) and around the center (retrograde). Some families become unstable or disappear in strong bars. A comparison is made with cases having one or no Inner Lindblad Resonance. (12 refs).

  1. Ten-day observation of live rabies suspected dogs.

    Science.gov (United States)

    Tepsumethanon, V; Wilde, H; Sitprija, V

    2008-01-01

    This study aimed at analyzing a ten-day observation period of rabies suspected dogs and cats according to six criteria. Dogs and cats suspected of being rabid were brought for observation when they had either bitten a person or another animal or when abnormal behaviour or unusual illness was observed. Between 1985 and 2005, retrospective and prospective data from 1,222 dogs and 303 cats was collected during the ten-day observation period. If an animal had died, brain examination using fluorescent antibody testing was routinely performed. If an animal had survived for > or =10 days, it was released to its owner or transferred to the municipal dog shelter. A total of 644 dogs and 58 cats found rabid died within 10 days of observation. In addition, for 208 dogs confirmed rabid with laboratory tests between 1997 and 2005, six criteria were analysed from the day of submission. This experience with the implemented 10-day observation period confirms the WHO recommendation on identifying suspected rabid dogs or cats under veterinary supervision following a human exposure.

  2. A Typical Presentation of Orbital Pseudotumor Mimicking Orbital Cellulitis

    Directory of Open Access Journals (Sweden)

    J. Ayatollahi

    2013-10-01

    Full Text Available Introduction: Orbital pseudotumor, also known as idiopathic orbital inflammatory syndrome (IOIS, is a benign, non- infective inflammatory condition of the orbit without identifiable local or systemic causes. The disease may mimics a variety of pathologic conditions. We pre-sent a case of pseudotumor observed in a patient admitted under the name of orbital celluli-ties. Case Report: A 26-year-old woman reffered to our hospital with the history of left ocular pain and headache 2 days before her visit.. Ophthalmological examination of the patient was normal except for the redness and lid edema, mild chemosis and conjunctival injection. Gen-eral assessment was normal but a low grade fever was observed. She was hospitalized as an orbital cellulitis patient. She was treated with intravenous antibiotics. On the third day , sud-denly diplopia, proptosis in her left eye and ocular pain in her right side appeared. MRI re-vealed bilateral enlargement of extraocular muscles. Diagnosis of orbital pseudotumor was made and the patient was treated with oral steroid.She responded promptly to the treatment. Antibiotics were discontinued and steroid was tapered in one month period under close fol-low up. Conclusion: The clinical features of orbital pseudotumor vary widely . Orbital pseudotumor and orbital cellulitis can occasionally demonstrate overlapping features.. Despite complete physical examination and appropriate imaging, sometimes correct diagnosis of the disease would be difficult (Sci J Hamadan Univ Med Sci 2013; 20 (3:256-259

  3. [Orbital complications of rhinosinusitis].

    Science.gov (United States)

    Stojanović, J; Ilić, N; Belić, B; Zivić, L; Stanković, P; Erdevicki, L; Jovanović, S

    2009-01-01

    Orbital complications were observed in 53 patients (1.35%, n=53/3912 of all treated patients; 11.04%, n= 53/480 of hospitalized patients). Complications in the orbit can occur in 3-5% of adults with the inflammatory condition of sinuses, while the percentage in children ranges from 0.5-8%. The objective of our work was to determine the frequency of the occurence of orbital complications of the rhinosinal inflammatory origin in a group of adults and children. The retrospective analysis of patients treated of rhinosinusitis in the period 1992 to 2007, in the Clinical Center in Kragujevac. In the period of 15 years, a total number of 3912 patients were treated for inflamatory conditions of paranasal cavities. Orbital complications were found in 53 patients (1.35%, n=53/3912 of all treated patients). The number of children showing orbital complications caused by rhinosinusitis was 0.79%, while the number of adults was 1,88%. Acute rhinosinusitis in children was manifested as orbital complication in 14 patients (n=14/15, 93.33%), while 33 adults (n=33/38, 86.84%) had the exarcerbation of the chronic rhinosinusitis at the time of diagnosis of orbital complication. 80% of examined children had the maxillary and ethmoid sinus infected (n=12/15), while the adults most often had polysinusitis (n=22/38, 57.89%). In the juvenile age the most frequent complication was the cellulitis of the orbite (n=7/15, 46.66%), while in the adults it was the subperiostal absces (n=14/38, 36.84%). The adults were mostly treated surgically (n=31/38, 81.58%), while the children were treated by using conservative treatment (n=13/15, 86.67%). There were no cases of mortality. The prevention of complications is based on the adequate and timely treatment of acute sinusitis in children, as well as the curative treatment of chronical processes in adults.

  4. Magnetic resonance imaging versus bone scintigraphy in suspected scaphoid fracture

    Energy Technology Data Exchange (ETDEWEB)

    Tiel-van Buul, M.M.C. [Dept. of Nuclear Medicine, Academic Medical Center, Univ. of Amsterdam (Netherlands); Roolker, W. [Dept. of Nuclear Medicine, Academic Medical Center, Univ. of Amsterdam (Netherlands); Verbeeten, B.W.B. Jr. [Dept. of Radiology, Academic Medical Center, Univ. of Amsterdam (Netherlands); Broekhuizen, A.H. [Dept. of Traumatology, Academic Medical Center, Univ. of Amsredam (Netherlands)

    1996-08-01

    Magnetic resonance imaging (MRI) has become increasingly useful in the evaluation of musculoskeletal problems, including those of the wrist. In patients with a wrist injury, MRI is used mainly to assess vascularity of scaphoid non-union. However, the use of MRI in patients in the acute phase following carpal injury is not common. Three-phase bone scintigraphy is routinely performed from at least 72 h after injury in patients with suspected scaphoid fracture and negative initial radiographs. We evaluated MRI in this patient group. The bone scan was used as the reference method. Nineteen patients were included. Bone scintigraphy was performed in all 19 patients, but MRI could be obtained in only 16 (in three patients, MRI was stopped owing to claustrophobia). In five patients, MRI confirmed a scintigraphically suspected scaphoid fracture. In one patient, a perilunar luxation, without a fracture, was seen on MRI, while bone scintigraphy showed a hot spot in the region of the lunate bone, suspected for fracture. This was confirmed by surgery. In two patients, a hot spot in the scaphoid region was suspected for scaphoid fracture, and immobilization and employed for a period of 12 weeks. MRI was negative in both cases; in one of them a scaphoid fracture was retrospectively proven on the initial X-ray series. In another two patients, a hot spot in the region of MCP I was found with a negative MRI. In both, the therapy was adjusted. In the remaining six patients, both modalities were negative. We conclude that in the diagnostic management of patients with suspected scaphoid fracture and negative initial radiographs, the use of MRI may be promising, but is not superior to three-phase bone scintigraphy. (orig.)

  5. A case of suspect “cyanosis”

    OpenAIRE

    Elisabetta Antonucci; Matteo Conte; Michele Di Pumpo; Giuseppe Antonucci

    2013-01-01

    CLINICAL CASE A 70-year old woman was admitted to our hospital because of fever, asthenia and a suspected stroke. Her medical history showed a congenital cardiopathy (Patent Foramen Ovale, PFO). Skin and oral mucosa pigmentation, orthostatic hypotension, hypoglycemia and hyponatriemia arose the suspect of Addison’s disease. The diagnosis was confirmed by the evaluation of basal levels of plasma ACTH and serum cortisol, and serum cortisol levels after ACTH stimulation. Abdominal CT scan showed...

  6. Inflammation of the Orbit

    Science.gov (United States)

    ... Glaucoma (Video) Macular Degeneration Additional Content Medical News Inflammation of the Orbit (Inflammatory Orbital Pseudotumor) By James ... Introduction to Eye Socket Disorders Cavernous Sinus Thrombosis Inflammation of the Orbit Orbital Cellulitis Preseptal Cellulitis Tumors ...

  7. The phenomenology of specialization of criminal suspects.

    Directory of Open Access Journals (Sweden)

    Michele Tumminello

    Full Text Available A criminal career can be either general, with the criminal committing different types of crimes, or specialized, with the criminal committing a specific type of crime. A central problem in the study of crime specialization is to determine, from the perspective of the criminal, which crimes should be considered similar and which crimes should be considered distinct. We study a large set of Swedish suspects to empirically investigate generalist and specialist behavior in crime. We show that there is a large group of suspects who can be described as generalists. At the same time, we observe a non-trivial pattern of specialization across age and gender of suspects. Women are less prone to commit crimes of certain types, and, for instance, are more prone to specialize in crimes related to fraud. We also find evidence of temporal specialization of suspects. Older persons are more specialized than younger ones, and some crime types are preferentially committed by suspects of different ages.

  8. Robustness analysis method for orbit control

    Science.gov (United States)

    Zhang, Jingrui; Yang, Keying; Qi, Rui; Zhao, Shuge; Li, Yanyan

    2017-08-01

    Satellite orbits require periodical maintenance due to the presence of perturbations. However, random errors caused by inaccurate orbit determination and thrust implementation may lead to failure of the orbit control strategy. Therefore, it is necessary to analyze the robustness of the orbit control methods. Feasible strategies which are tolerant to errors of a certain magnitude can be developed to perform reliable orbit control for the satellite. In this paper, first, the orbital dynamic model is formulated by Gauss' form of the planetary equation using the mean orbit elements; the atmospheric drag and the Earth's non-spherical perturbations are taken into consideration in this model. Second, an impulsive control strategy employing the differential correction algorithm is developed to maintain the satellite trajectory parameters in given ranges. Finally, the robustness of the impulsive control method is analyzed through Monte Carlo simulations while taking orbit determination error and thrust error into account.

  9. Epidemiology of suspected wrist joint infection versus inflammation.

    Science.gov (United States)

    Skeete, Kshamata; Hess, Erik P; Clark, Tod; Moran, Steven; Kakar, Sanjeev; Rizzo, Marco

    2011-03-01

    To determine the cumulative prevalence of septic arthritis presenting to the emergency department of an academic medical center and evaluate the use of clinical data to diagnose infection versus inflammation. We conducted a records review of a single institution with 80,000 annual emergency room visits. We included a consecutive series of patients with suspected wrist infection from January 1, 2007, to December 31, 2008. Adults complaining of atraumatic wrist pain with either erythema or swelling on physical examination or a final diagnosis of septic arthritis, gout, pseudogout, cellulitis, wrist hematoma/edema, or wrist arthritic flare were suspected to have infection. We collected data using a standardized data abstraction form. We reviewed 804 patient records. A total of 104 patients meeting inclusion criteria for suspected wrist joint infection during the 2-year study period were included. Mean age was 62.5 years (SD, 20.2 y); 63 were men. There were 12 patients with a history of gout, 4 with a history of pseudogout, and 19 with a history of diabetes. Wrist arthrocentesis was performed in 31 patients, and 11 underwent surgical treatment. There were 16 patients with a final diagnosis of gout, 11 with pseudogout, 43 with cellulitis, 13 with upper extremity hematoma/edema, and 15 with wrist arthritic flare. The cumulative prevalence of septic arthritis was 5%. In this series of emergency department patients with suspected wrist joint infection, gout, pseudogout, and cellulitis were the most common etiologies. The cumulative incidence of septic wrist arthritis was low. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  10. A case of suspect “cyanosis”

    Directory of Open Access Journals (Sweden)

    Elisabetta Antonucci

    2013-05-01

    Full Text Available CLINICAL CASE A 70-year old woman was admitted to our hospital because of fever, asthenia and a suspected stroke. Her medical history showed a congenital cardiopathy (Patent Foramen Ovale, PFO. Skin and oral mucosa pigmentation, orthostatic hypotension, hypoglycemia and hyponatriemia arose the suspect of Addison’s disease. The diagnosis was confirmed by the evaluation of basal levels of plasma ACTH and serum cortisol, and serum cortisol levels after ACTH stimulation. Abdominal CT scan showed atrophy and calcification of adrenal glands. CONCLUSIONS In most cases, Addison’s disease is provoked by autoimmune destruction of the adrenal cortex; however, in our reported patient, tuberculosis could be a possible cause.

  11. Congenital Malaria Among Newborns Admitted for Suspected ...

    African Journals Online (AJOL)

    Background: Signs and symptoms of congenital malaria do not differ much from those of neonatal sepsis: both can co-exist, and most times very difficult to differentiate clinically. Objective: To document the prevalence, risk factors for congeni tal malar ia among neonates admitted for suspected neonatal sepsis, and ...

  12. Congenital Malaria Among Newborns Admitted for Suspected ...

    African Journals Online (AJOL)

    None of the clinical feature had good sensitivity, specificity or predictive value for congenital malaria, and only 1.6% death was recorded in a baby with high parasite density. Conclusion: Congenital malaria is common in newborns with suspected neonatal sepsis. History of peripartum pyrexia, prematurity and intrauterine ...

  13. MRI for clinically suspected appendicitis during pregnancy.

    NARCIS (Netherlands)

    Cobben, L.P.; Groot, I.; Haans, L.; Blickman, J.G.; Puylaert, J.

    2004-01-01

    OBJECTIVE: The purpose of this study was to evaluate whether MRI can be used to accurately diagnose or exclude appendicitis in pregnant patients with clinically suspected appendicitis. CONCLUSION: Our results suggest that MRI is helpful in the examination and diagnosis of acute appendicitis in

  14. Biomechanical properties of keratoconus suspect eyes.

    Science.gov (United States)

    Saad, Alain; Lteif, Yara; Azan, Elodie; Gatinel, Damien

    2010-06-01

    Measuring corneal biomechanical properties may help detect keratoconus suspect corneas and eliminate the risk of ectasia after LASIK. Data of 504 eyes separated into three groups were retrospectively reviewed: normal (n = 252), keratoconus suspect (n = 80), and keratoconus (n = 172). Corneal hysteresis (CH) and corneal resistance factor (CRF) were measured with an ocular biomechanics analyzer. Mean corneal hysteresis was 10.6 +/- 1.4 (SD) mm Hg in the normal group, compared with 10.0 +/- 1.6 mm Hg in the keratoconus suspect group and 8.1 +/- 1.4 mm Hg in the keratoconus group. The mean CRF was 10.6 +/- 1.6 mm Hg in the normal group compared with 9.7 +/- 1.7 in the keratoconus suspect group and 7.1 +/- 1.6 mm Hg in the keratoconus group. Mean CH and CRF were significantly different between the three groups (P corneas. Analyzing signal curves obtained with the biomechanics analyzer may provide additional valuable information for selecting qualified patients for refractive surgery.

  15. Characterization of suspected illegal skin whitening cosmetics.

    Science.gov (United States)

    Desmedt, B; Van Hoeck, E; Rogiers, V; Courselle, P; De Beer, J O; De Paepe, K; Deconinck, E

    2014-03-01

    An important group of suspected illegal cosmetics consists of skin bleaching products, which are usually applied to the skin of the face, hands and décolleté for local depigmentation of hyper pigmented regions or more importantly, for a generalized reduction of the skin tone. These cosmetic products are suspected to contain illegal active substances that may provoke as well local as systemic toxic effects, being the reason for their banning from the EU market. In that respect, illegal and restricted substances in cosmetics, known to have bleaching properties, are in particular hydroquinone, tretinoin and corticosteroids. From a legislative point of view, all cosmetic products containing a prohibited whitening agent are illegal and must be taken off the EU market. A newly developed screening method using ultra high performance liquid chromatography-time off flight-mass spectrometry allows routine analysis of suspected products. 163 suspected skin whitening cosmetics, collected by Belgian inspectors at high risk sites such as airports and so-called ethnic cosmetic shops, were analyzed and 59% were classified as illegal. The whitening agents mostly detected were clobetasol propionate and hydroquinone, which represent a serious health risk when repeatedly and abundantly applied to the skin. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Suspecting Neurological Dysfunction From E Mail Messages ...

    African Journals Online (AJOL)

    A non medical person suspected and confirmed neurological dysfunction in an individual, based only on e mail messages sent by the individual. With email communication becoming rampant “peculiar” email messages may raise the suspicion of neurological dysfunction. Organic pathology explaining the abnormal email ...

  17. Boxy Orbital Structures in Rotating Bar Models

    Science.gov (United States)

    Chaves-Velasquez, L.; Patsis, P. A.; Puerari, I.; Skokos, Ch.; Manos, T.

    2017-12-01

    We investigate regular and chaotic two-dimensional (2D) and three-dimensional (3D) orbits of stars in models of a galactic potential consisting of a disk, a halo, and a bar to find the origin of boxy components that are part of the bar or (almost) the bar itself. Our models originate in snapshots of an N-body simulation, which develops a strong bar. We consider three snapshots of the simulation, and, for the orbital study, we treat each snapshot independently, as an autonomous Hamiltonian system. The calculated corotation–to–bar length ratios indicate that in all three cases, the bar rotates slowly, while the orientation of the orbits of the main family of periodic orbits changes along its characteristic. We characterize the orbits as regular, sticky, or chaotic after integrating them for a 10 Gyr period by using the GALI2 index. Boxiness in the equatorial plane is associated either with quasi-periodic orbits in the outer parts of stability islands or with sticky orbits around them, which can be found in a large range of energies. We indicate the location of such orbits in diagrams, which include the characteristic of the main family. They are always found about the transition region from order to chaos. By perturbing such orbits in the vertical direction, we find a class of 3D nonperiodic orbits, which have boxy projections both in their face-on and side-on views.

  18. Families of three-dimensional periodic solutions in the circular restricted four-body problem

    Science.gov (United States)

    Papadakis, K. E.

    2016-04-01

    In this paper we study the 3D symmetric periodic orbits of the circular restricted four-body problem, through their bifurcation from plane orbits. To this end, we calculate the special generating planar periodic orbits, i.e. the vertical-critical orbits, from five basic planar families of symmetric periodic orbits of the problem. We study the simplest 3D periodic orbits and so we restrict our calculations to simple vertical bifurcation orbits leading to families of one or two revolutions three-dimensional symmetric periodic orbits. We found 21 such families of simple 3D symmetric periodic orbits and typical orbits of all symmetry type 3D orbits are presented. The stability of each calculated 3D periodic orbit is also studied. Characteristic curves as well as stability diagrams of families of 3D periodic orbits are illustrated.

  19. Imaging trends in suspected appendicitis-a Canadian perspective.

    Science.gov (United States)

    Tan, Victoria F; Patlas, Michael N; Katz, Douglas S

    2017-06-01

    The purpose of our study was to assess trends in the imaging of suspected appendicitis in adult patients in emergency departments of academic centers in Canada. A questionnaire was sent to all 17 academic centers in Canada to be completed by a radiologist who works in emergency radiology. The questionnaires were sent and collected over a period of 4 months from October 2015 to February 2016. Sixteen centers (94%) responded to the questionnaire. Eleven respondents (73%) use IV contrast-enhanced computed tomography (CT) as the imaging modality of choice for all patients with suspected appendicitis. Thirteen respondents (81%) use ultrasound as the first modality of choice in imaging pregnant patients with suspected appendicitis. Eleven respondents (69%) use ultrasound (US) as the first modality of choice in patients younger than 40 years of age. Ten respondents (67%) use ultrasound as the first imaging modality in female patients younger than 40 years of age. When CT is used, 81% use non-focused CT of the abdomen and pelvis, and 44% of centers use oral contrast. Thirteen centers (81%) have ultrasound available 24 h a day/7 days a week. At 12 centers (75%), ultrasound is performed by ultrasound technologists. Four centers (40%) perform magnetic resonance imaging (MRI) in suspected appendicitis in adult patients at the discretion of the attending radiologist. Eleven centers (69%) have MRI available 24/7. All 16 centers (100%) use unenhanced MRI. Various imaging modalities are available for the work-up of suspected appendicitis. Although there are North American societal guidelines and recommendations regarding the appropriateness of the multiple imaging modalities, significant heterogeneity in the first-line modalities exist, which vary depending on the patient demographics and resource availability. Imaging trends in the use of the first-line modalities should be considered in order to plan for the availability of the imaging examinations and to consider plans for

  20. Mercury's rotation axis and period

    Science.gov (United States)

    Klaasen, K. P.

    1976-01-01

    Recent measurements made from high-resolution Mariner 10 photography of the planet Mercury yield a rotation period of 58.6461 + or 0.005 days, in excellent agreement with the period required for a precise 2/3 resonance with its orbital period (58.6462 days). The axis of rotation of the planet was calculated to be offset about 2 deg from the perpendicular to its orbital plane within a 50% probability error ellipse of + or - 2.6 deg by + or - 6.5 deg. Dynamical considerations make it most likely that the true displacement from the orbit normal is less than 1 deg.

  1. Orbital melanoma with calcification: A diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Sukhdeep Bains

    2016-01-01

    Full Text Available Primary orbital melanoma is rare and has varied initial presentation. A 28-year-old female presented with proptosis and decreased vision in the left eye. Computed tomography scan showed an orbital mass with contrast enhancement and calcification around the optic nerve leading to a diagnosis of meningioma. The patient chose to be on observation. Loss of vision with an increase in proptosis was seen at 6 months follow-up. On surgical exploration, a well-defined pigmented mass was seen encasing the optic nerve. Histopathological analysis revealed a malignant melanoma. Metastatic workup was negative. Left eye lid sparing exenteration was done. A high index of suspicion is necessary in a rapidly growing suspected optic nerve sheath meningioma and a differential diagnosis including orbital melanoma be considered.

  2. Mercury's resonant rotation from secular orbital elements

    OpenAIRE

    Stark, Alexander; Oberst, Jürgen; Hussmann, Hauke

    2015-01-01

    We used recently produced Solar System ephemerides, which incorporate 2 years of ranging observations to the MESSENGER spacecraft, to extract the secular orbital elements for Mercury and associated uncertainties. As Mercury is in a stable 3:2 spin-orbit resonance, these values constitute an important reference for the planet’s measured rotational parameters, which in turn strongly bear on physical interpretation of Mercury’s interior structure. In particular, we derive a mean orbital period o...

  3. The evaluation of suspected child physical abuse.

    Science.gov (United States)

    Christian, Cindy W

    2015-05-01

    Child physical abuse is an important cause of pediatric morbidity and mortality and is associated with major physical and mental health problems that can extend into adulthood. Pediatricians are in a unique position to identify and prevent child abuse, and this clinical report provides guidance to the practitioner regarding indicators and evaluation of suspected physical abuse of children. The role of the physician may include identifying abused children with suspicious injuries who present for care, reporting suspected abuse to the child protection agency for investigation, supporting families who are affected by child abuse, coordinating with other professionals and community agencies to provide immediate and long-term treatment to victimized children, providing court testimony when necessary, providing preventive care and anticipatory guidance in the office, and advocating for policies and programs that support families and protect vulnerable children. Copyright © 2015 by the American Academy of Pediatrics.

  4. THREE PLANETS ORBITING WOLF 1061

    Energy Technology Data Exchange (ETDEWEB)

    Wright, D. J.; Wittenmyer, R. A.; Tinney, C. G.; Bentley, J. S.; Zhao, Jinglin, E-mail: duncan.wright@unsw.edu.au [Department of Astronomy and Australian Centre for Astrobiology, School of Physics, University of New South Wales, NSW 2052 (Australia)

    2016-02-01

    We use archival HARPS spectra to detect three planets orbiting the M3 dwarf Wolf 1061 (GJ 628). We detect a 1.36 M{sub ⊕} minimum-mass planet with an orbital period P = 4.888 days (Wolf 1061b), a 4.25 M{sub ⊕} minimum-mass planet with orbital period P = 17.867 days (Wolf 1061c), and a likely 5.21 M{sub ⊕} minimum-mass planet with orbital period P = 67.274 days (Wolf 1061d). All of the planets are of sufficiently low mass that they may be rocky in nature. The 17.867 day planet falls within the habitable zone for Wolf 1061 and the 67.274 day planet falls just outside the outer boundary of the habitable zone. There are no signs of activity observed in the bisector spans, cross-correlation FWHMs, calcium H and K indices, NaD indices, or Hα indices near the planetary periods. We use custom methods to generate a cross-correlation template tailored to the star. The resulting velocities do not suffer the strong annual variation observed in the HARPS DRS velocities. This differential technique should deliver better exploitation of the archival HARPS data for the detection of planets at extremely low amplitudes.

  5. Suspects in criminal investigations of rape

    Directory of Open Access Journals (Sweden)

    Marinković Darko

    2014-01-01

    Full Text Available Investigations of sexual assaults mostly focus on victims and their credibility, which may cause lack of firm evidence in relation to suspects. Given the fact that the criminal offence of rape is characterised by a high incidence of false reports and accusations, frequently indicating specific persons as the perpetrators, certain caution is necessary in the investigation in order to avoid false accusations and/or convictions. As regards the personality of the rapist and motives for committing a forcible sexual act, certain types or rather certain categories of perpetrators can be distinguished, although it should be noted that a large number of rapists do not belong to one category only, but rather combine characteristics of several different types. During a criminal investigation it is of vital importance to differentiate between a rape as a surprise attack and a rape as abuse of trust, as they are compatible with the nature of the suspect's defence. The suspect shall be subjected to a forensic examination in the course of the investigation in order to find traces which prove vaginal, anal or oral penetration, coerced sexual intercourse and identity of the rapist. While conducting an interrogation of a suspected rapist, a crime investigating officer shall use either factual or emotional approach to his interviewee, depending on his psychological and motivational characteristics. In this regard, the factual approach is believed to be more efficient with anger rapists and sadistic rapists, whereas the compassionate approach gives good results with the gentlemen-rapists and partly with the power asserting rapists.

  6. Glaucoma suspect & Humphrey Field Analyzer a correlation

    Directory of Open Access Journals (Sweden)

    P Dahal

    2012-09-01

    Full Text Available Glaucoma originally meant "clouded", in Greek.The term glaucoma refers to a group of diseases that have in common characteristic optic neuropathy with associated visual field loss for which elevated intraocular pressure is one of the primary risk factor. The purpose of the study is to correlate the clinically diagnosed cases of glaucoma suspect with the Humphrey Field Analyzer (HFA. Fifty cases of glaucoma suspect who attended the glaucoma clinic of Nepal Eye Hospital Tripureswor, Kathmandu, Nepal and who meets at least two criteria, among the four types of glaucoma suspects were advised for the HFA for the study. In this study out of 50 patient, 36 (72% patients had normal visual field. 14 (28% patients had thinning of the neural retinal rim (NRR in both eyes. The significant relation with thinning of neural retina rim and glaucomatous hemifield test was found in the study. Journal of College of Medical Sciences-Nepal,2012,Vol-8,No-1, 23-28 DOI: http://dx.doi.org/10.3126/jcmsn.v8i1.6822

  7. Tocolytics for suspected intrapartum fetal distress.

    Science.gov (United States)

    Kulier, R; Hofmeyr, G J

    2000-01-01

    Prophylactic tocolysis with betamimetics and other agents has become widespread as a treatment for fetal distress. Uterine relaxation may improve placental blood flow and therefore fetal oxygenation. However there may also be adverse maternal cardiovascular effects. The objective of this review was to assess the effects of tocolytic therapy for suspected fetal distress on fetal, maternal and perinatal outcomes. We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register. Date of last search: February 1999. Randomised trials comparing tocolytic therapy with no treatment or treatment with another tocolytic agent for suspected fetal distress. Two reviewers assessed trial quality and extracted data. Three studies were included. Compared with no treatment, there were fewer failed improvements in fetal heart rate abnormalities with tocolytic therapy (relative risk 0.26, 95% 0.13 to 0.53). Betamimetic therapy compared with magnesium sulphate showed a non-significant trend towards reduced uterine activity (relative risk 0.07, 95% confidence interval 0.00 to 1.10). Betamimetic therapy appears to be able to reduce the number of fetal heart rate abnormalities and perhaps reduce uterine activity. However there is not enough evidence based on clinically important outcomes to evaluate the use of betamimetics for suspected fetal distress.

  8. Catalogue of Cometary Orbits 1995. Tenth edition.

    Science.gov (United States)

    Marsden, B. G.; Williams, G. V.

    This tenth edition of the Catalogue of Cometary Orbits differs from its predecessors in that it utilizes the new cometary designation system that took effect at the beginning of 1995, adopted by the IAU in August 1994. It contains 1472 orbits for 1444 cometary apparitions and is intended to be complete for comets observed through the end of 1994. Contents: 1. Introduction. 2. General catalogue (long-period and unnumbered periodic comets, numbered periodic comets). 3. Identifications. 4. 1995 elements for numbered periodic comets. 5. Statistical tables (periodic comets of more than one appearance, periodic comets of only one appearance, comets that may be of short period, parabolic and nearly-parabolic orbits in order of i). 6. Correspondence of new-style and old-style designations (by Roman numeral, by letter designation). 7. X/comets.

  9. Perioperative sexual interest in women with suspected gynecologic malignancies.

    Science.gov (United States)

    Bretschneider, C E; Bensen, Jeannette T; Geller, Elizabeth J; Gehrig, Paola A; Wu, Jennifer M; Doll, Kemi M

    2017-07-01

    For women with gynecologic cancer, the impact of surgery on sexual interest and desire in the immediate and later postoperative period is not well characterized. The objective of this study was to report the perioperative trends of changing sexual interest and desire in a cohort of women undergoing surgery for suspected gynecologic malignancies. This is an ancillary analysis of a cohort study analyzing health-related outcomes in women who underwent primary surgical management of a suspected gynecologic malignancy between 10/2013 and 10/2014. Subjects completed the Patient-Reported Outcomes Measurement Information System Sexual Function and Satisfaction Questionnaire (PROMIS-SFQ) preoperatively and questions on sexual interest and desire at one, three, and six months postoperatively. Bivariate tests and multiple linear regression were used to analyze data. Of 231 women who completed a baseline PROMIS-SFQ, 187 (81%) completed one-month, 170 (74%) three-month, and 174 (75%) six-month follow-up interviews. Following surgery, 71% of enrolled subjects were diagnosed with a malignancy. Women age women age >55 (-5.5±1.0 vs -2.3±0.9, p=0.02). In a multivariable analysis, age women of all ages (-5.6, 95% CI: -9.6, -1.5). This study provides new data regarding the timing and magnitude of changes in sexual interest following gynecologic oncology procedures. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Orbital Inflammation Developing from Epidemic Keratoconjunctivitis in an Adult

    Directory of Open Access Journals (Sweden)

    Sung In Kim

    2013-08-01

    Full Text Available Introduction: We report a rare case of epidemic keratoconjunctivitis (EKC that developed into an orbital inflammation in an adult. Case Presentation: A 67-year-old Korean man, who had been diagnosed with EKC and treated for conjunctival injection and chemosis in the right eye for 4 days, was referred to Oculoplastics as orbital cellulitis was suspected. At the point of referral, clinical features such as decreased visual acuity, severe eyelid swelling, chemosis, follicles, corneal edema, limitations in lateral eye movement, and diplopia were observed in the right eye. Orbital cellulitis was suspected according to orbital computed tomography scan images, but there was no response to systemic antibiotics. Systemic steroid was administered instead, and then his symptoms and signs started to improve. The final diagnosis of this patient was orbital inflammation related to EKC based on the facts that there was no response to antibiotics, that he presented with contralateral symptoms and signs, that pseudomembrane formation occurred in both eyes, and that the symptoms resolved completely after 2 weeks. Conclusion: Clinicians need to consider the possibility of orbital inflammation developing from EKC, even in an adult patient, and treat the patient properly if the EKC symptoms and signs, such as conjunctival injection and follicles, are accompanied with symptoms and signs similar to orbital cellulitis.

  11. Prevalence of glaucoma suspects and pattern of intra-ocular ...

    African Journals Online (AJOL)

    Background: Glaucoma is the commonest cause of irreversible blindness in the world. Some glaucoma patients start out as glaucoma suspects for years. Aim: To determine the prevalence of glaucoma suspects and pattern of intra-ocular pressure distribution in glaucoma suspects. Methods: This survey was carried out in ...

  12. Nuclear Pedigree Criteria of Suspected HNPCC

    Directory of Open Access Journals (Sweden)

    Kładny Józef

    2003-01-01

    Full Text Available Abstract The criteria for the diagnosis of HNPCC established by the ICG-HNPCC are very restrictive as they do not allow for the diagnosis of a large number of "suspected HNPCC" cases - these are families which do no fulfill the strict diagnostic "Amsterdam criteria", but do present with several pedigree and clinical features characteristic for HNPCC. Several series of families suspected of harboring germline mutations in DNA mismatch repair genes have been studied for germline changes in DNA mismatch repair genes and a mutation rate of somewhere between 8-60% was found. Therefore a subgroup of members of the ICG-HNPCC has been working on pedigree/clinical diagnostic criteria for suspected HNPCC. Materials and methods Part I The study was based on two series of colorectal cancer (CRC cases: 1 HNPCC - this group comprised 190 patients affected by CRC from randomly selected families which fulfilled the Amsterdam II criteria registered in Düsseldorf, Germany (102 cases of CRC, Denmark (18 CRCs, Leiden, Holland (23 CRCs and Szczecin, Poland (47 CRCs. 2 Consecutive CRCs - this group comprised 629 (78.0% of 806 individuals with CRC diagnosed in 1991-1997 in the city of Szczecin (ca. 400,000 of inhabitants, Poland. Nuclear pedigrees in both groups were compared for frequency of occurrence of clinical features, that have been shown to be associated with HNPCC. Part II 52 consecutive CRC cases from Szczecin, matching the criteria recognized in part I as appropriate for diagnosis of cases "suspected of HNPCC" were studied for the occurrence of germline hMSH2/hMLH1 constitutional mutations using "exon by exon" sequencing. Results The combination of features - i.e. the occurrence of an HNPCC associated cancer (CRC or cancer of the endometrium, small bowel or urinary tract in a 1st degree relative of a CRC patient; at least one of the patients being diagnosed under age of 50 - appeared to be strongly associated to HNPCC with an OR - 161. Constitutional

  13. Continuation of Sets of Constrained Orbit Segments

    DEFF Research Database (Denmark)

    Schilder, Frank; Brøns, Morten; Chamoun, George Chaouki

    Sets of constrained orbit segments of time continuous flows are collections of trajectories that represent a whole or parts of an invariant set. A non-trivial but simple example is a homoclinic orbit. A typical representation of this set consists of an equilibrium point of the flow and a trajectory...... that starts close and returns close to this fixed point within finite time. More complicated examples are hybrid periodic orbits of piecewise smooth systems or quasi-periodic invariant tori. Even though it is possible to define generalised two-point boundary value problems for computing sets of constrained...... orbit segments, this is very disadvantageous in practice. In this talk we will present an algorithm that allows the efficient continuation of sets of constrained orbit segments together with the solution of the full variational problem....

  14. Validation of Galileo orbits using SLR with a focus on satellites launched into incorrect orbital planes

    Science.gov (United States)

    Sośnica, Krzysztof; Prange, Lars; Kaźmierski, Kamil; Bury, Grzegorz; Drożdżewski, Mateusz; Zajdel, Radosław; Hadas, Tomasz

    2017-07-01

    The space segment of the European Global Navigation Satellite System (GNSS) Galileo consists of In-Orbit Validation (IOV) and Full Operational Capability (FOC) spacecraft. The first pair of FOC satellites was launched into an incorrect, highly eccentric orbital plane with a lower than nominal inclination angle. All Galileo satellites are equipped with satellite laser ranging (SLR) retroreflectors which allow, for example, for the assessment of the orbit quality or for the SLR-GNSS co-location in space. The number of SLR observations to Galileo satellites has been continuously increasing thanks to a series of intensive campaigns devoted to SLR tracking of GNSS satellites initiated by the International Laser Ranging Service. This paper assesses systematic effects and quality of Galileo orbits using SLR data with a main focus on Galileo satellites launched into incorrect orbits. We compare the SLR observations with respect to microwave-based Galileo orbits generated by the Center for Orbit Determination in Europe (CODE) in the framework of the International GNSS Service Multi-GNSS Experiment for the period 2014.0-2016.5. We analyze the SLR signature effect, which is characterized by the dependency of SLR residuals with respect to various incidence angles of laser beams for stations equipped with single-photon and multi-photon detectors. Surprisingly, the CODE orbit quality of satellites in the incorrect orbital planes is not worse than that of nominal FOC and IOV orbits. The RMS of SLR residuals is even lower by 5.0 and 1.5 mm for satellites in the incorrect orbital planes than for FOC and IOV satellites, respectively. The mean SLR offsets equal -44.9, -35.0 , and -22.4 mm for IOV, FOC, and satellites in the incorrect orbital plane. Finally, we found that the empirical orbit models, which were originally designed for precise orbit determination of GNSS satellites in circular orbits, provide fully appropriate results also for highly eccentric orbits with variable

  15. Cycler orbit between Earth and Mars

    Science.gov (United States)

    Byrnes, Dennis V.; Longuski, James M.; Aldrin, Buzz

    1993-06-01

    A periodic orbit between Earth and Mars has been discovered that, after launch, permits a space vehicle to cycle back and forth between the planets with moderate maneuvers at irregular intervals. A Space Station placed in this cycler orbit could provide a safe haven from radiation and comfortable living quarters for astronauts en route to Earth or Mars. The orbit is largely maintained by gravity assist from Earth. Numerical results from multiconic optimization software are presented for a 15-year period from 1995 through 2010.

  16. Preseptal Cellulitis, Orbital Cellulitis, Orbital Abscess

    Directory of Open Access Journals (Sweden)

    Rana Altan Yaycıoğlu

    2012-12-01

    Full Text Available Patients with orbital infections present to our clinic usually with unilateral pain, hyperemia, and edema of the eyelids. The differentiation between preseptal and orbital cellulitis is utmost important in that the second requires hospitalization. Since in orbital cellulitis, the tissues posterior to the orbital septum are involved, signs such as conjunctival chemosis, limited eye movement, decreased vision, as well as afferent pupil defect secondary to optic nerve involvement may also be observed. Prompt intravenous antibiotic treatment should be started, and surgical drainage may be performed if patient shows failure to improve in 48 hours despite optimal management. Without treatment, the clinical course may progress to subperiosteal or orbital abscess, and even to cavernous sinus thrombosis. (Turk J Ophthalmol 2012; 42: Supplement 52-6

  17. Transneptunian Orbit Computation

    Science.gov (United States)

    Virtanen, J.; Tancredi, G.; Bernstein, G. M.; Spahr, T.; Muinonen, K.

    We review the orbit computation problem for the transneptunian population. For these distant objects, the problem is characterized by their short observed orbital arcs, which are known to be coupled with large uncertainties in orbital elements. Currently, the observations of even the best observed objects, such as the first-ever transneptunian object (TNO), Pluto, cover only a fraction of their revolution. Furthermore, of the some 1200 objects discovered since 1992, roughly half have observations from only one opposition. To ensure realistic analyses of the population, e.g., in the derivation of unbiased orbital distributions or correlations between orbital and physical properties, realistic estimation of orbital uncertainties is important. We describe the inverse problem of orbit computation, emphasizing the short-arc problem and its statistical treatment. The complete solution to the problem can be given in terms of the orbital-element probability density function (p.d.f.), which then serves as a starting point for any further analysis, where knowledge of orbital uncertainties is required. We give an overview of the variety of computational techniques developed for TNO orbital uncertainty estimation in the recent years. After presenting the current orbital distribution, we demonstrate their application to several prediction problems, such as classification, ephemeris prediction, and dynamical analysis of objects. We conclude with some future prospects for TNO orbit computation concerning the forthcoming next-generation surveys, including the anticipated evolution of TNO orbital uncertainties over the coming decades.

  18. Cost-effectiveness of routine imaging of suspected appendicitis.

    Science.gov (United States)

    D'Souza, N; Marsden, M; Bottomley, S; Nagarajah, N; Scutt, F; Toh, S

    2018-01-01

    Introduction The misdiagnosis of appendicitis and consequent removal of a normal appendix occurs in one in five patients in the UK. On the contrary, in healthcare systems with routine cross-sectional imaging of suspected appendicitis, the negative appendicectomy rate is around 5%. If we could reduce the rate in the UK to similar numbers, would this be cost effective? This study aimed to calculate the financial impact of negative appendicectomy at the Queen Alexandra Hospital and to explore whether a policy of routine imaging of such patients could reduce hospital costs. Materials and methods We performed a retrospective analysis of all appendicectomies over a 1-year period at our institution. Data were extracted on outcomes including appendix histology, operative time and length of stay to calculate the negative appendicectomy rate and to analyse costs. Results A total of 531 patients over 5 years of age had an appendicectomy. The negative appendicectomy rate was 22% (115/531). The additional financial costs of negative appendicectomy to the hospital during this period were £270,861. Universal imaging of all patients with right iliac fossa pain that could result in a 5% negative appendicectomy rate would cost between £67,200 and £165,600 per year but could save £33,896 (magnetic resonance imaging), £105,896 (computed tomography) or £132,296 (ultrasound) depending on imaging modality used. Conclusions Negative appendicectomy is still too frequent and results in additional financial burden to the health service. Routine imaging of patients with suspected appendicitis would not only reduce the negative appendicectomy rate but could lead to cost savings and a better service for our patients.

  19. ASC Champ Orbit Model

    DEFF Research Database (Denmark)

    Riis, Troels; Jørgensen, John Leif

    1999-01-01

    This documents describes a test of the implementation of the ASC orbit model for the Champ satellite.......This documents describes a test of the implementation of the ASC orbit model for the Champ satellite....

  20. Lunar Orbiter Photo Gallery

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Orbiter Photo Gallery is an extensive collection of over 2,600 high- and moderate-resolution photographs produced by all five of the Lunar Orbiter...

  1. Orbital Cellulitis: Clinical Course and Management Challenges. The ...

    African Journals Online (AJOL)

    Background: Orbital cellulitis is a devastating acute infection of orbital soft tissues located posterior to the orbital septum. It is both vision and life-threatening. It is an ocular emergency which most often present in childhood. Objective: This article reviewed cases presenting during the study period with the view of examining ...

  2. Introducing Earth's Orbital Eccentricity

    Science.gov (United States)

    Oostra, Benjamin

    2015-01-01

    Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is…

  3. Idiopathic granulomatous orbital inflammation

    NARCIS (Netherlands)

    Mombaerts, I.; Schlingemann, R. O.; Goldschmeding, R.; Koornneef, L.

    1996-01-01

    PURPOSE: Granulomatous orbital inflammation may occur as an isolated condition of unknown origin. These idiopathic granulomatous lesions are believed to belong to the orbital pseudotumor group by some authors, whereas others consider them sarcoidosis limited to the orbit. The aim of this study is to

  4. Long-period clocks from short-period oscillators

    Science.gov (United States)

    Labavić, Darka; Meyer-Ortmanns, Hildegard

    2017-08-01

    We analyze repulsively coupled Kuramoto oscillators, which are exposed to a distribution of natural frequencies. This source of disorder leads to closed orbits of repetitive temporary patterns of phase-locked motion, providing clocks on macroscopic time scales. The periods can be orders of magnitude longer than the periods of individual oscillators. By construction, the attractor space is quite rich. This may cause long transients until the deterministic trajectories find their stationary orbits. The smaller the width of the distribution about the common natural frequency, the longer are the emerging time scales on average. Among the long-period orbits, we find self-similar sequences of temporary phase-locked motion on different time scales. The ratio of time scales is determined by the ratio of widths of the distributions. The results illustrate a mechanism for how simple systems can provide rather flexible dynamics, with a variety of periods even without external entrainment.

  5. Restoration of the orbital aesthetic subunit in complex midface defects.

    Science.gov (United States)

    Chepeha, Douglas B; Wang, Steven J; Marentette, Lawrence J; Bradford, Carol R; Boyd, Charles M; Prince, Mark E; Teknos, Theodoros N

    2004-10-01

    Although various options exist for restoration of the orbital defect in complex craniofacial resections, the aesthetic appearance and functional result of the orbit are optimized when the bony orbital architecture, orbital volume, and facial contour are specifically addressed. The study describes an approach using free tissue transfer for restoration of the native orbital aesthetic subunit. Retrospective case series. Nineteen patients (male-to-female ratio, 14:5; mean age, 52 y [age range, 8-79 y]) in the study period between 1997 and 2001 had orbital defects that could be classified into one of the following categories: 1) orbital exenteration cavities only, 2) orbital exenteration cavities with resection of less than 30% of the bony orbital rim, or 3) radical orbital exenteration cavities with resection of overlying skin and bony malar eminence. Group 1 had reconstructions with fasciocutaneous forearm flaps; group 2, with osseocutaneous forearm flaps; and group 3, with osseocutaneous scapula flaps. Eighteen of 19 patients achieved a closed orbital reconstruction with restoration of the orbital aesthetic subunit. Among 16 patients with more than 4 months of follow-up, 10 patients had minimal or no resulting facial contour deformity and 8 patients engaged in social activities outside the home on a frequent basis. Five of the nine patients who were working before their surgery were able to return to work. Patients with complex midface defects involving the orbit can undergo free tissue transfer and have successful restoration of the native orbital aesthetic subunit without an orbital prosthesis.

  6. Satellite orbits design using frequency analysis

    Science.gov (United States)

    Noullez, A.; Tsiganis, K.; Tzirti, S.

    2015-07-01

    We present here a new method for the efficient computation of periodic orbits, which are of particular interest for low-altitude satellite orbits design in high degree/order, non-axisymmetric gravity models. Our method consists of an iterative filtering scheme, that is itself based on 'Prony's method' of frequency analysis, and is independent of the complexity of the gravity model. Applying this method to the case of a low-altitude lunar orbiter, we show that it converges rapidly, in all models and for all values of altitude and initial inclination studied. Thus, as demonstrated below, one could use it to correct the initial conditions of a desired mission orbit - usually defined within the framework of a simplified model (e.g. the 'J2 problem') - ensuring minimal orbital eccentricity variations and, for very low altitudes, collision avoidance. At the same time, an accurate quasi-periodic decomposition of the orbit is computed, giving a measure of the periodic fluctuations of the orbital parameters.

  7. Families of Keplerian orbits

    Energy Technology Data Exchange (ETDEWEB)

    Butikov, Eugene I [St Petersburg State University, St Petersburg (Russian Federation)

    2003-03-01

    Various properties of Keplerian orbits traced by satellites that are launched from one and the same spatial point with different initial velocities are discussed. Two families of elliptical orbits are investigated, namely the sets of orbits produced by a common direction but different magnitudes of the initial velocities, and by a common magnitude but various directions of the initial velocities. For the latter family, the envelope of all the orbits is found, which is the boundary of the spatial region occupied by the orbits.

  8. Families of Keplerian orbits

    CERN Document Server

    Butikov, E I

    2003-01-01

    Various properties of Keplerian orbits traced by satellites that are launched from one and the same spatial point with different initial velocities are discussed. Two families of elliptical orbits are investigated, namely the sets of orbits produced by a common direction but different magnitudes of the initial velocities, and by a common magnitude but various directions of the initial velocities. For the latter family, the envelope of all the orbits is found, which is the boundary of the spatial region occupied by the orbits.

  9. Orbital fractures: a review

    Directory of Open Access Journals (Sweden)

    Jeffrey M Joseph

    2011-01-01

    Full Text Available Jeffrey M Joseph, Ioannis P GlavasDivision of Ophthalmic Plastic and Reconstructive Surgery, Department of Ophthalmology, School of Medicine, New York University, New York, NY, USA; Manhattan Eye, Ear, and Throat Hospital, New York, NY, USAAbstract: This review of orbital fractures has three goals: 1 to understand the clinically relevant orbital anatomy with regard to periorbital trauma and orbital fractures, 2 to explain how to assess and examine a patient after periorbital trauma, and 3 to understand the medical and surgical management of orbital fractures. The article aims to summarize the evaluation and management of commonly encountered orbital fractures from the ophthalmologic perspective and to provide an overview for all practicing ophthalmologists and ophthalmologists in training.Keywords: orbit, trauma, fracture, orbital floor, medial wall, zygomatic, zygomatic complex, zmc fracture, zygomaticomaxillary complex fractures 

  10. Role of DR-70 immunoassay in suspected malignant pleural effusion

    Science.gov (United States)

    Sengupta, Amitabha; Saha, Kaushik; Jash, Debraj; Banerjee, Sourindra Nath; Biswas, Nirendra Mohan; Dey, Atin

    2013-01-01

    Context: A good proportion of patients with undiagnosed pleural effusion (PE) turn into malignancy over a period of time. Identification of positive biomarker may help in selecting the individuals who require close follow-up. Aims: The aims of this study were to evaluate the role of DR-70 immunoassay in suspected malignant PE. Settings and Design: We conducted a cross-sectional study among 89 patients of suspected malignant PE and 50 normal subjects (NS) were taken as control. Materials and Methods: Patients with exudative PE; who had pleural fluid lymphocyte count greater than 50% and adenosine deaminase less than 30 U/L were taken as cases. We had selected NSs among relatives of patients having normal blood chemistry and radiological investigations. Sensitivity and specificity of the test to differentiate malignant and non-malignant PE and also to identify PE with underlying malignancy was analyzed. Results: Mean value of DR-70 in NS was found to be 0.83 ± 0.273 mg/L without any significant difference between males (0.82 mg/L) and females (0.85 mg/L). Mean value of DR-70 in PE with underlying cancer was 5.03 ± 3.79 mg/L. Sensitivity (80%) and specificity (77.78%) of the test was maximum in PE with underlying cancer using cut-off value of 2 mg/L. Mean value DR-70 in malignant PE was 5.18 ± 3.75 mg/L and in non-malignant PE was 3.73 ± 3.74 mg/L without any statistically significant difference (P = 0.08). Conclusions: DR-70 assay has high sensitivity in detecting underlying lung cancer, but has no role in differentiating malignant PE from non-malignant PE. PMID:24339491

  11. Retinoblastoma presenting with orbital cellulitis.

    Science.gov (United States)

    Walinjkar, Jaydeep; Krishnakumar, S; Gopal, Lingam; Ramesh, Anita; Khetan, Vikas

    2013-06-01

    To study the effectiveness of pre-enucleation steroids in reducing inflammation in patients with retinoblastoma presenting as orbital cellulitis. Medical records of consecutive retinoblastoma patients presenting at a single tertiary eye care center during a period of 3 years were retrospectively reviewed. For those who presented with orbital cellulitis, clinical, radiological, and histopathological variables were assessed. The effect of pre-enucleation steroids was noted in this group of patients. Of 260 retinoblastoma cases reviewed, 14 had retinoblastoma-associated cellulitis (5.39%). Of these 14 patients, 4 received neoadjuvant chemotherapy and were excluded from the series. Of the remaining 10 cases (mean age at presentation, 14.2 months; mean follow-up, 16.4 months), 9 presented with orbital cellulitis and were included in the study. Radiological imaging depicted intraocular tumors occupying 80% to 100% of the globe in each case. All patients underwent enucleation. Five children received pre-enucleation systemic steroids (mean, 5.4 days), which resulted in a prompt decrease in inflammation. Postenucleation chemotherapy was administered in 4 (6 cycles) and external beam radiation therapy in 1 patient with high-risk histopathological characteristics. Advanced necrotic retinoblastoma with anterior segment involvement may present as orbital cellulitis. Pre-enucleation systemic steroids can aid in the surgical management of these tumors. Copyright © 2013 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

  12. Period doubling patterns of interval maps

    CERN Document Server

    Valaristos, A

    2003-01-01

    We prove the existence and demonstrate the construction of period doubling patterns centered at periodic orbits of continuous maps on the interval. In particular we prove that f in R: =set membership C sup 0 (I,I) exhibits a period doubling pattern centered at a fixed point of f if and only if the set of periodic points is not closed. Furthermore, we prove that if f has a periodic orbit of period n>1, which is not a power of two, and n .pr. m in Sarkovskii's ordering, then f exhibits a period doubling pattern centered at a periodic orbit of period m. An analytic configuration of such period doubling patterns is exhibited.

  13. Magnetic resonance imaging of suspected atrial tumors.

    Science.gov (United States)

    Menegus, M A; Greenberg, M A; Spindola-Franco, H; Fayemi, A

    1992-05-01

    Two-dimensional echocardiography has become the standard technique for evaluation of cardiac and paracardiac mass lesions. We have used magnetic resonance imaging (MRI) as an independent assessment of cardiac-associated masses in patients with echocardiograms demonstrating sessile atrial tumors. MRI was performed in seven patients, ages 33 to 84, whose echocardiographic diagnoses included left atrial mass (five), right atrial mass (one), and interatrial mass (one). In four of the patients with a diagnosis of left atrial mass, MRI showed extracardiac compression of the atrium, simulating a tumor (hiatal hernia, tortuous descending aorta, bronchogenic cyst). MRI was entirely normal in one patient with an apparent left atrial mass. MRI elucidated extension of an extracavitary mass into the interatrial septum in two patients. One of these patients with an echocardiographic right atrial mass had extension of a lipoma into the interatrial septum without atrial tumor. MRI confirmed the echocardiographic diagnosis of an interatrial mass in the other patient. We conclude that MRI, because of its ability to define anatomic relationships and tissue characteristics, is a powerful noninvasive tool for evaluating suspected cardiac mass lesions. Although echocardiography remains the primary screening test for the detection of cardiac masses, MRI is a more specific modality for precise diagnosis. Correct MRI interpretation may obviate the need for invasive studies or surgery.

  14. NASA Educational Briefs for the Classroom. Orbits of Bodies in Space

    Science.gov (United States)

    1982-01-01

    The difference between an orbit and a revolution is explained and it is shown why space shuttle Columbia's period of revolution was longer than its orbital period. Parameters of orbits examined include apoapsis, periapsis, apogee, perigee, aphelion, perihelion, orbital plane, and inclination. Orbit velocity and duration, Newton's law of gravitation, and Kepler's three laws of motion are considered. The principles involved in geostationary satellites are also explored.

  15. Neonatal orbital abscess

    Directory of Open Access Journals (Sweden)

    Khalil M Al-Salem

    2014-01-01

    Full Text Available Orbital complications due to ethmoiditis are rare in neonates. A case of orbital abscess due to acute ethmoiditis in a 28-day-old girl is presented. A Successful outcome was achieved following antimicrobial therapy alone; spontaneous drainage of the abscess occurred from the lower lid without the need for surgery. From this case report, we intend to emphasize on eyelid retraction as a sign of neonatal orbital abscess, and to review all the available literature of similar cases.

  16. Orbital metastases of prostatic carcinoma in a tropical African ...

    African Journals Online (AJOL)

    We have reviewed the cases of orbital metastases from carcinoma of the prostate gland seen in the University College Hospital, Ibadan over an 11 year period, 1990 – 2000. During the period, seven cases of orbital metastases that presumably arose from carcinoma of the prostate were seen. Four of the patients died of ...

  17. Family of Orbiters

    Science.gov (United States)

    2008-01-01

    This image shows the paths of three spacecraft currently in orbit around Mars, as well as the path by which NASA's Phoenix Mars Lander will approach and land on the planet. The t-shaped crosses show where the orbiters will be when Phoenix enters the atmosphere, while the x-shaped crosses show their location at landing time. All three orbiters, NASA's Mars Reconnaissance Orbiter, NASA's Mars Odyssey and the European Space Agency's Mars Express, will be monitoring Phoenix during the final steps of its journey to the Red Planet. Phoenix will land just south of Mars's north polar ice cap.

  18. Observable Priors: Limiting Biases in Estimated Parameters for Incomplete Orbits

    Science.gov (United States)

    Kosmo, Kelly; Martinez, Gregory; Hees, Aurelien; Witzel, Gunther; Ghez, Andrea M.; Do, Tuan; Sitarski, Breann; Chu, Devin; Dehghanfar, Arezu

    2017-01-01

    Over twenty years of monitoring stellar orbits at the Galactic center has provided an unprecedented opportunity to study the physics and astrophysics of the supermassive black hole (SMBH) at the center of the Milky Way Galaxy. In order to constrain the mass of and distance to the black hole, and to evaluate its gravitational influence on orbiting bodies, we use Bayesian statistics to infer black hole and stellar orbital parameters from astrometric and radial velocity measurements of stars orbiting the central SMBH. Unfortunately, most of the short period stars in the Galactic center have periods much longer than our twenty year time baseline of observations, resulting in incomplete orbital phase coverage--potentially biasing fitted parameters. Using the Bayesian statistical framework, we evaluate biases in the black hole and orbital parameters of stars with varying phase coverage, using various prior models to fit the data. We present evidence that incomplete phase coverage of an orbit causes prior assumptions to bias statistical quantities, and propose a solution to reduce these biases for orbits with low phase coverage. The explored solution assumes uniformity in the observables rather than in the inferred model parameters, as is the current standard method of orbit fitting. Of the cases tested, priors that assume uniform astrometric and radial velocity observables reduce the biases in the estimated parameters. The proposed method will not only improve orbital estimates of stars orbiting the central SMBH, but can also be extended to other orbiting bodies with low phase coverage such as visual binaries and exoplanets.

  19. Has Nemesis' orbit been detected?

    Science.gov (United States)

    Delsemme, A. H.

    1986-01-01

    The orbital angular momenta of 126 very young comets are calculated from the orbital data of Marsden and Roemer (1982) and analyzed statistically. A large anisotropy is detected in a plane almost perpendicular to the ecliptic and shown to have a characteristic dissipation lifetime of 10-30 Myr. Dynamic evolution computations indicate that the impulse which produced the anisotropy is that of a very slow massive (10-90 Jupiter mass) body, which is bound to the solar system, passed its 15,000-35,000-AU perihelion about 2-15 Myr ago, and has period 5-50 Myr. It is suggested that this body could well be identical to Nemesis, the object proposed to explain mass faunal extinctions.

  20. The Orbiting Primate Experiment (OPE)

    Science.gov (United States)

    Bourne, G. H.; Debourne, M. N. G.; Mcclure, H. M.

    1977-01-01

    Instrumentation and life support systems are described for an experiment to determine the physiological effects of long term space flight on unrestrained, minimally instrumented rhesus macaques flown in orbit for periods up to six months or one year. On return from orbit, vestibular, cardiovascular, and skeletal muscle function will be tested. Blood chemistry and hematological studies will be conducted as well as tests of the immunological competence of selected animals. Nasal, rectal, and throat swabs will be used for bacterial and viral studies, and histopathological and histochemical investigations will be be made of all organs using light and electron microscopy. The experiment is being considered as a payload for the biomedical experiment scientific satellite.

  1. Impaled Orbital TASER Probe Injury Requiring Primary Enucleation.

    Science.gov (United States)

    Rafailov, Leon; Temnogorod, Jenny; Tsai, Frank F; Shinder, Roman

    The Conducted Electrical Weapon is a weapon often used by law enforcement agencies as a method of less lethal means to subdue a suspect. Injuries to the eye with these devices are usually due to the projectile force of the metal probes that are released when these devices are engaged. The authors report what may be the first case of an impaled orbital TASER probe that required primary enucleation for globe perforation.

  2. Uranian ring orbits from earth-based and Voyager occultation observations

    Science.gov (United States)

    French, Richard G.; Elliot, J. L.; French, Linda M.; Kangas, Julie A.; Meech, Karen J.

    1988-01-01

    A novel kinematical model of the Uranian rings has been derived from Voyager occultation timings and earth-based observations of the occultations of U23, U25, and U28, to yield an improved orbit solution that is accurate to about 1 km in the ring plane; this allows a critical comparison to be conducted between ring locations and suspected resonances. The gamma ring is noted to have a peculiar orbit that combines a precessing elliptical ring with a radially-oscillating normal mode. The kinematical model confirms the suspected association of resonances between the 1986U7 and 1986U8 satellites with some of the rings.

  3. Detection of Rabies antigen in brains of suspected Rabid dogs ...

    African Journals Online (AJOL)

    Objective: To detect the presence of rabies antigen in brains of suspected rabid dogs. Materials and Methods: Ninety six (96) brain specimens from suspected rabid dogs were examined for the presence of rabies antigen using Seller's staining technique and enzyme immunoassay. Results: The two techniques were both ...

  4. 48 CFR 803.806 - Processing suspected violations.

    Science.gov (United States)

    2010-10-01

    ... GENERAL IMPROPER BUSINESS PRACTICES AND PERSONAL CONFLICTS OF INTEREST Limitation on the Payment of Funds to Influence Federal Transactions 803.806 Processing suspected violations. A VA employee must report suspected violations of 31 U.S.C. 1352, Limitation on Use of Appropriated Funds to Influence Certain Federal...

  5. The clinical course of patients with suspected pulmonary embolism

    NARCIS (Netherlands)

    van Beek, E. J.; Kuijer, P. M.; Büller, H. R.; Brandjes, D. P.; Bossuyt, P. M.; ten Cate, J. W.

    1997-01-01

    BACKGROUND: The outcome of patients with suspected pulmonary embolism is known to a limited extent only. OBJECTIVE: To address this limited knowledge in a cohort in whom pulmonary embolism was proved or ruled out. METHODS: Consecutive patients with clinically suspected pulmonary embolism underwent

  6. Seasonal variation among tuberculosis suspects in four countries

    DEFF Research Database (Denmark)

    Mabaera, Biggie; Naranbat, Nymadawa; Katamba, Achilles

    2009-01-01

    The objective of the study was to analyze monthly trends across a calendar year in tuberculosis suspects and sputum smear-positive cases based on nationally representative samples of tuberculosis laboratory registers from Moldova, Mongolia, Uganda and Zimbabwe. Out of the 47 140 suspects registered...... in the tuberculosis laboratory registers, 13.4% (6312) were cases. The proportion varied from country to country, Moldova having the lowest (9%) and Uganda the highest (21%). From the monthly proportion of suspects and cases among total suspects and cases, seasonal variations were most marked in Mongolia which, among...... attendance to diagnostic laboratory services, evidenced by the contrasting findings of Mongolia (extreme continental northern climate) compared to Uganda (equatorial climate). A combination of external and possibly endogenous factors seems to determine whether tuberculosis suspects and cases present...

  7. Survey of laboratory findings in suspected cases of bovine spongiform encephalopathy in Denmark from 1990 to 2000

    DEFF Research Database (Denmark)

    Agerholm, J.S.; Tegtmeier, C.L.; Nielsen, T.K.

    2002-01-01

    . A total of 176 submissions were made, mostly from bovines with neurological disorders and mainly during the last 3 years of this period. Lesions or other laboratory findings consistent with severe neurological disorders were found in 115 cases. The most frequent diagnosis was encephalic 41 p listeriosis......A survey of the laboratory findings in suspected cases of bovine spongiform encephalopathy (BSE) in Denmark from I June 1990 to '31 December 2000 is presented. During this period BSE was a notifiable disease, and the heads of suspected cases were submitted according to the legislation on BSE...

  8. Presentation and management of pediatric orbital cellulitis.

    Science.gov (United States)

    Fanella, Sergio; Singer, Alex; Embree, Joanne

    2011-01-01

    Orbital cellulitis is a serious, vision-threatening infection. To review the epidemiology and clinical data of pediatric orbital cellulitis in Manitoba. A 12-year retrospective review was conducted of all children (younger than 18 years of age) with orbital cellulitis admitted to Manitoba's only tertiary pediatric centre. Admission rates for orbital cellulitis were compared over three distinct time periods, based on licensure and funding levels of the heptavalent pneumococcal conjugate vaccine (PCV7) in Manitoba. Thirty-eight patients with orbital cellulitis were identified. Of these, 11% were of Aboriginal ethnicity in contrast with 30% to 40% of children who were admitted for other respiratory illnesses. Subperiosteal abscesses occurred in 31.5%. Only eight patients (21%) required surgery. Follow-up imaging after presentation usually did not indicate a need for subsequent surgical drainage. The mean number of orbital cellulitis cases per 1000 admissions for the following periods - before PCV7 licensure, after licensure and before full provincial funding, and after licensure and full funding - were 0.39, 0.53 and 0.90, respectively. No significant difference was noted among any of the periods as PCV7 coverage increased. The rate of subperiosteal abscesses was lower than other reports. This may be due to the median age at presentation. In contrast to admissions for most other respiratory infections at the Winnipeg Children's Hospital (Winnipeg, Manitoba), Aboriginal ethnicity was uncommon. Surprisingly, rates of admissions for orbital cellulitis appeared to show an increasing trend with increasing access to PCV7 in Manitoba, although overall the number of cases was very small. Studies into the changing microbiology of orbital cellulitis and sinusitis are warranted.

  9. Orbital ordering and frustrations

    NARCIS (Netherlands)

    Khomskii, D.I.; Mostovoy, M.V.

    2003-01-01

    Orbital ordering occurs in many transition metal compounds with Jahn–Teller ions (Cu2+, Mn3+, low-spin Ni3+, Ti3+ etc). It plays an important role in these materials. At the same time, exchange interactions in orbitally degenerate systems are inherently frustrated, even in materials with simple

  10. CONGENITAL ORBITAL TERATOMA

    African Journals Online (AJOL)

    commenced on topical chloramphenicol therapy. The x-ray showed a left orbital soft tissue mass but no orbital enlargement and the swab showed no growth. ... proliferating neural bundles and some neural bundles lined by pigmented choroidal epithelium. Also seen are abundant fibrous tissues scattered within the.

  11. Small-Bowel Capsule Endoscopy in Patients with Suspected Crohn's Disease—Diagnostic Value and Complications

    Science.gov (United States)

    Figueiredo, Pedro; Almeida, Nuno; Lopes, Sandra; Duque, Gabriela; Freire, Paulo; Lérias, Clotilde; Gouveia, Hermano; Sofia, Carlos

    2010-01-01

    Background. The aim of this work was to assess the value of capsule enteroscopy in the diagnosis of patients with suspected Crohn's Disease (CD). Methods. This was a retrospective study in a single tertiary care centre involving patients undergoing capsule enteroscopy for suspected CD. Patients taking nonsteroidal anti inflammatory drugs during the thirty preceding days or with a follow-up period of less than six months were excluded. Results. Seventy eight patients were included. The endoscopic findings included mucosal breaks in 50%, ulcerated stenosis in 5%, and villous atrophy in 4%. The diagnosis of CD was established in 31 patients. The sensitivity, specificity, positive and negative predictive value of the endoscopic findings were 93%, 80%, 77%, and 94%, respectively. Capsule retention occurred in four patients (5%). The presence of ulcerated stenosis was significantly more frequent in patients with positive inflammatory markers. The diagnostic yield of capsule enteroscopy in patients with negative ileoscopy was 56%, with a diagnostic acuity of 93%. Conclusions. Small bowel capsule endoscopy is a safe and valid technique for assessing patients with suspected CD. Capsule retention is more frequent in patients with positive inflammatory markers. Patients with negative ileoscopy and suspected CD should be submitted to capsule enteroscopy. PMID:20811612

  12. Peripheral orbit model

    CERN Document Server

    Hara, Yasuo

    1975-01-01

    Peripheral orbit model, in which an incoming hadron is assumed to revolve in a peripheral orbit around a target hadron, is discussed. The non-diffractive parts of two-body reaction amplitudes of hadrons are expressed in terms of the radius, width an absorptivity of the orbit. The radius of the orbit is about 1 fm and the width of the orbit is determined by the range of the interaction between the hadrons. The model reproduces all available experimental data on differential cross-sections and polarizations of $K^{-}p\\to K^{-}p$ and $\\bar K^{\\circ}n$ reactions for all angles successfully. This contribution is not included in the proceedings since it will appear in Progress of Theoretical Physics Vol. 51 (1974) No 2. Any person interested in the subject may apply for reprints to the author.

  13. Transfer and capture into distant retrograde orbits

    Science.gov (United States)

    Scott, Christopher J.

    This dissertation utilizes theory and techniques derived from the fields of dynamical systems theory, astrodyanamics, celestial mechanics, and fluid mechanics to analyze the phenomenon of satellite capture and interrelated spacecraft transfers in restricted three-body systems. The results extend current knowledge and understanding of capture dynamics in the context of astrodynamics and celestial mechanics. Manifold theory, fast Lyapunov indicator maps, and the classification of space structure facilitate an analysis of the transport of objects from the chaotic reaches of the solar system to the distant retrograde region in the sun-Jupiter system. Apart from past studies this dissertation considers the role of the complex lobe structure encompassing stable regions in the circular restricted three-body problem. These structures are shown to be responsible for the phenomenon of sticky orbits and the transport of objects among stable regions. Since permanent capture can only be achieved through a change in energy, fast Lyapunov indicator maps and other methods which reveal the structure of the conservative system are used to discern capture regions and identify the underpinnings of the dynamics. Fast Lyapunov indicator maps provide an accurate classification of orbits of permanent capture and escape, yet monopolize computational resources. In anticipation of a fully three-dimensional analysis in the dissipative system a new mapping parameter is introduced based on energy degradation and averaged velocity. Although the study specifically addresses the sun-Jupiter system, the qualitative results and devised techniques can be applied throughout the solar system and to capture about extrasolar planets. Extending the analysis beyond the exterior of the stable distant retrograde region fosters the construction of transfer orbits from low-Earth orbit to a stable periodic orbit at the center of the stable distant retrograde region. Key to this analysis is the predictability of

  14. Acute aortic dissection in patient with suspected pheochromocytoma

    Directory of Open Access Journals (Sweden)

    Lešanović Jelena

    2016-01-01

    Full Text Available Introduction: Aortic dissection is one of the most fatal vascular emergencies. Almost 40% of the patients do not reach hospital in time while more than quarter die in the first 24 hours after the dissection begins. Case Report: A 37-year old man was admitted to our hospital with severe anterior chest pain which had lasted for over a week. Suspected aortic dissection was rapidly confirmed using imaging modalities - MDCT chest scan and TTE, followed by an urgent surgical management - Bentall procedure. MDCT chest scan also discovered adrenal incidentaloma defined as malignant, pheochromocytoma like mass. Due to the critical state of the patient, there was not enough time for further endocrinologic testing. Discussion and conclusion: When treating patients with pheochromocytoma and acute aortic disection, it is crucial to obtain a stable hemodynamic state before the surgery, since they can trigger a severe hypertensive crisis due to high levels of cathecholamines induced chronic vasoconctriction. The most vulnerable periods are the induction of anesthesia and perioperative hemodynamic oscillations, so treating patients with short acting alpha- 1 adrenergic blocking agents preoperatively has proven to be helpful - Phentolamine. Both dissection of aorta and pheochromocytoma present challenges for anesthesiologists and early recognition of symptoms is essential in establishing the diagnosis and reducing the mortality rate.

  15. Pegging the porous orbital implant.

    Science.gov (United States)

    Johnson, Royce L C; Ramstead, Cory L; Nathoo, Nawaaz

    2011-01-01

    Hydroxyapatite (HA) orbital implants are commonly used for the anophthalmic socket. With a HA implant, if motility is not satisfactory then a peg system can be surgically placed in attempts to improve motility. The authors report the technique and results of 83 patients who received motility peg placement over an 8-year period by a single surgeon. Retrospective chart review of all patients with previous enucleation with either primary or secondary insertion of a HA implant who received a motility peg by a single oculoplastic surgeon between January 1999 and February 2007. Eighty-three patients underwent placement of a titanium peg and sleeve during the study period. Complications seen in the follow-up period included discharge, pyogenic granuloma, and others. Infection was experienced in 1 case. Fourteen patients (17%) required further surgical management due to complications. The largely positive results of this moderately sized case series validates the efficacy of pegging a hydroxyapatite orbital implant with minor risk of serious complications; this may have been due to a combination of factors including an experienced surgeon and adequate follow-up. As a procedure that can be completed in a hospital or minor surgical suite with sedation, it remains a viable option for many patients.

  16. Prediction of Suspect Location Based on Spatiotemporal Semantics

    Directory of Open Access Journals (Sweden)

    Lian Duan

    2017-06-01

    Full Text Available The prediction of suspect location enables proactive experiences for crime investigations and offers essential intelligence for crime prevention. However, existing studies have failed to capture the complex social location transition patterns of suspects and lack the capacity to address the issue of data sparsity. This paper proposes a novel location prediction model called CMoB (Crime Multi-order Bayes model based on the spatiotemporal semantics to enhance the prediction performance. In particular, the model groups suspects with similar spatiotemporal semantics as one target suspect. Then, their mobility data are applied to estimate Markov transition probabilities of unobserved locations based on a KDE (kernel density estimating smoothing method. Finally, by integrating the total transition probabilities, which are derived from the multi-order property of the Markov transition matrix, into a Bayesian-based formula, it is able to realize multi-step location prediction for the individual suspect. Experiments with the mobility dataset covering 210 suspects and their 18,754 location records from January to June 2012 in Wuhan City show that the proposed CMoB model significantly outperforms state-of-the-art algorithms for suspect location prediction in the context of data sparsity.

  17. Orbital variations and outbursts of the unusual variable star V1129 Centauri

    Science.gov (United States)

    Bruch, Albert

    2017-11-01

    The variable star V1129 Cen is classified in the GCVS as being of β Lyr type. Unusual for such stars, it exhibits outbursts roughly once a year, lasting for ∼ 40 days. For this reason, a relationship to the dwarf novae has been suspected. Here, for the first time a detailed analysis of the light curve of the system is presented. Based on observations with high time resolution obtained at the Observatório do Pico dos Dias and on the long term ASAS light curve the orbital variations of the system are studied. They are dominated by ellipsoidal variations and partial eclipses of a probably slightly evolved F2 star in a binary with an orbital period of 21h 26m. Comparison with the characteristics of dwarf novae show that the observational properties of V1129 Cen can be explained if it is just another dwarf novae, albeit with an unusually bright and early type mass donor which outshines the accretion disk and the mass gainer to a degree that many normal photometric and spectroscopic hallmarks of cataclysmic variables remain undetected.

  18. Orbital cellulitis in children.

    Science.gov (United States)

    Nageswaran, Savithri; Woods, Charles R; Benjamin, Daniel K; Givner, Laurence B; Shetty, Avinash K

    2006-08-01

    To review the epidemiology and management of orbital cellulitis in children. The medical records of children orbital cellulitis and confirmed by computed tomography scan were reviewed. A literature search for additional studies for systematic review was also conducted. Forty-one children with orbital cellulitis were identified. The mean age was 7.5 years (range, 10 months to 16 years), and 30 (73%) were male (male:female ratio = 2.7). All cases of orbital cellulitis were associated with sinusitis; ethmoid sinusitis was present in 40 (98%) patients. Proptosis and/or ophthalmoplegia was documented in 30 (73%), and 34 (83%) had subperiosteal and/or orbital abscesses. Twenty-nine (71%) had surgical drainage and 12 (29%) received antibiotic therapy only. The mean duration of hospitalization was 5.8 days. The mean duration of antibiotic therapy was 21 days. Orbital cellulitis occurs throughout childhood and in similar frequency among younger and older children. It is twice as common among males as females. Selected cases of orbital cellulitis, including many with subperiosteal abscess, can be treated successfully without surgical drainage.

  19. B Plant/WESF suspect/counterfeit parts identification program

    Energy Technology Data Exchange (ETDEWEB)

    Mertz, D.W.

    1996-01-12

    This document describes a suspect/counterfeit parts inspection program required by DOE conducted in accordance with Internal Memo 16710-94-DWM-048, J.A. O`Brien to J. N. Nansen, B Plant Suspect/ Counterfeit Parts Action Plan, dated May 24, 1994. The program included: physical inspection of all spare parts inventories within the plant; screening of installed B Plant/WESF (Waste Encapsulation and Storage Facility) systems for applications where the use and subsequent potential failure of suspect/counterfeit parts could have critical consequences; and a physical inspection based upon this screening.

  20. Orbital cystic neurinoma.

    Science.gov (United States)

    Tokugawa, J; Nakao, Y; Mori, K; Maeda, M

    2003-07-01

    A 64-year-old woman presented with a 6-month history of exophthalmus of her right eye. She had no neurological deficit except for the exophthalmus and numbness in the right side of her forehead (frontal nerve territory). Neuro-imaging demonstrated a cystic mass in the right orbit. The tumour was totally removed by microsurgical transcranial surgery. The histological diagnosis was neurinoma. The origin of the tumour was considered to be the frontal nerve. Only two other cases of orbital cystic neurinoma have been reported. This rare clinical entity should be included in the differential diagnosis of a cystic mass in the orbit.

  1. Quark Orbital Angular Momentum

    Directory of Open Access Journals (Sweden)

    Burkardt Matthias

    2015-01-01

    Full Text Available Definitions of orbital angular momentum based on Wigner distributions are used as a framework to discuss the connection between the Ji definition of the quark orbital angular momentum and that of Jaffe and Manohar. We find that the difference between these two definitions can be interpreted as the change in the quark orbital angular momentum as it leaves the target in a DIS experiment. The mechanism responsible for that change is similar to the mechanism that causes transverse single-spin asymmetries in semi-inclusive deep-inelastic scattering.

  2. The orbital record in stratigraphy

    Science.gov (United States)

    Fischer, Alfred G.

    1992-01-01

    , and (2) presence of abundant microfossils yields close ties to geochronology. A tantalizing possibility that stratigraphy may yield a record of orbital signals unrelated to climate has turned up in magnetic studies of our Cretaceous core. Magnetic secular variations here carry a strong 39 ka periodicity, corresponding to the theoretical obliquity period of that time - Does the obliquity cycle perhaps have some direct influence on the magnetic field?

  3. Historiske perioder

    DEFF Research Database (Denmark)

    2017-01-01

    For at forstå fortiden og fortællingerne om den, må vi skabe en form for orden og systematik. Her spiller inddelingen af fortiden i historiske perioder en afgørende rolle – og historiske perioder er da også et kompetencemål efter 6. klasse. Videoen diskuterer forskellige principper...... for periodisering. Kronologi og sammenhænge hænger naturligt sammen med historiske perioder. Videoen handler også om forståelser og brug af synkrone og diakrone sammenhænge i faget....

  4. Congenital orbital teratoma

    Directory of Open Access Journals (Sweden)

    Shereen Aiyub

    2013-01-01

    Full Text Available We present a case of mature congenital orbital teratoma managed with lid-sparing exenteration and dermis fat graft. This is a case report on the management of congenital orbital teratoma. A full-term baby was born in Fiji with prolapsed right globe which was surrounded by a nonpulsatile, cystic mass. Clinical and imaging features were consistent with congenital orbital teratoma. Due to limited surgical expertise, the patient was transferred to Adelaide, Australia for further management. The patient underwent a lid-sparing exenteration with frozen section control of the apical margin. A dermis fat graft from the groin was placed beneath the lid skin to provide volume. Histopathology revealed mature tissues from each of the three germ cell layers which confirmed the diagnosis of mature teratoma. We describe the successful use of demis fat graft in socket reconstruction following lid-sparing exenteration for congenital orbital teratoma.

  5. Orbital heat rate package

    Science.gov (United States)

    Lovin, J. K.; Spradley, L. W.

    1979-01-01

    Package consisting of three separate programs used to accurately predict temperature distribution of spacecraft in planetary orbit is invaluable tool for design and analysis of other structures that must function in complex thermal environment.

  6. Neonatal orbital abscess

    Directory of Open Access Journals (Sweden)

    Pratik Y Gogri

    2015-01-01

    Full Text Available Orbital abscess generally occurs in older children but it can rarely affect infants and neonates too. We report a case of community acquired methicillin resistant staphylococcus aureus (CA-MRSA neonatal orbital abscess in a 12-day-old term female neonate with no significant past medical history or risk factor for developing the infection. The case highlights the importance of consideration of CA-MRSA as a causative agent of neonatal orbital cellulitis even in a neonate without any obvious predisposing condition. Prompt initiation of appropriate medical therapy against MRSA and surgical drainage of the abscess prevents life threatening complications of orbital cellulitis which more often tend to be fatal in neonates.

  7. Orbital interactions in chemistry

    CERN Document Server

    Albright, Thomas A; Whangbo, Myung-Hwan

    2013-01-01

    Explains the underlying structure that unites all disciplines in chemistry Now in its second edition, this book explores organic, organometallic, inorganic, solid state, and materials chemistry, demonstrating how common molecular orbital situations arise throughout the whole chemical spectrum. The authors explore the relationships that enable readers to grasp the theory that underlies and connects traditional fields of study within chemistry, thereby providing a conceptual framework with which to think about chemical structure and reactivity problems. Orbital Interactions

  8. Stopping and Questioning Suspected Shoplifters Without Creating Civil Liability

    Science.gov (United States)

    Reed, Jack R., Jr.

    1977-01-01

    Legal problems concerned with shoplifting suspects are addressed, including common law, criminal penalties, and the merchant's liability. Tangential questions and answers are presented along with discussion of pertinent court cases. (LBH)

  9. ALGORITHM OF MANAGEMENT OF PATIENTS WITH SUSPECTED BLUNT CARDIAC TRAUMA

    Directory of Open Access Journals (Sweden)

    S. R. Gilarevsky

    2013-01-01

    Full Text Available Abstract. Contemporary algorithm of diagnostic examination of patients with suspected blunt cardiac trauma is presented. General aspects of monitoring and treatment of such patients are also discussed. 

  10. Suspect confession of child sexual abuse to investigators.

    Science.gov (United States)

    Lippert, Tonya; Cross, Theodore P; Jones, Lisa; Walsh, Wendy

    2010-05-01

    Increasing the number of suspects who give true confessions of sexual abuse serves justice and reduces the burden of the criminal justice process on child victims. With data from four communities, this study examined confession rates and predictors of confession of child sexual abuse over the course of criminal investigations (final N = 282). Overall, 30% of suspects confessed partially or fully to the crime. This rate was consistent across the communities and is very similar to the rates of suspect confession of child sexual abuse found by previous research, although lower than that from a study focused on a community with a vigorous practice of polygraph testing. In a multivariate analysis, confession was more likely when suspects were younger and when more evidence of abuse was available, particularly child disclosure and corroborative evidence. These results suggest the difficulty of obtaining confession but also the value of methods that facilitate child disclosure and seek corroborative evidence, for increasing the odds of confession.

  11. Spin-Orbital Order Modified by Orbital Dilution in Transition-Metal Oxides: From Spin Defects to Frustrated Spins Polarizing Host Orbitals

    Directory of Open Access Journals (Sweden)

    Wojciech Brzezicki

    2015-03-01

    Full Text Available We investigate the changes in spin and orbital patterns induced by magnetic transition-metal ions without an orbital degree of freedom doped in a strongly correlated insulator with spin-orbital order. In this context, we study the 3d ion substitution in 4d transition-metal oxides in the case of 3d^{3} doping at either 3d^{2} or 4d^{4} sites, which realizes orbital dilution in a Mott insulator. Although we concentrate on this doping case as it is known experimentally and more challenging than other oxides due to finite spin-orbit coupling, the conclusions are more general. We derive the effective 3d−4d (or 3d−3d superexchange in a Mott insulator with different ionic valencies, underlining the emerging structure of the spin-orbital coupling between the impurity and the host sites, and demonstrate that it is qualitatively different from that encountered in the host itself. This derivation shows that the interaction between the host and the impurity depends in a crucial way on the type of doubly occupied t_{2g} orbital. One finds that in some cases, due to the quench of the orbital degree of freedom at the 3d impurity, the spin and orbital order within the host is drastically modified by doping. The impurity either acts as a spin defect accompanied by an orbital vacancy in the spin-orbital structure when the host-impurity coupling is weak or favors doubly occupied active orbitals (orbital polarons along the 3d−4d bond leading to antiferromagnetic or ferromagnetic spin coupling. This competition between different magnetic couplings leads to quite different ground states. In particular, for the case of a finite and periodic 3d atom substitution, it leads to striped patterns either with alternating ferromagnetic or antiferromagnetic domains or with islands of saturated ferromagnetic order. We find that magnetic frustration and spin degeneracy can be lifted by the quantum orbital flips of the host, but they are robust in special regions of the

  12. The Lunar Orbital Prospector

    Science.gov (United States)

    Redd, Frank J.; Cantrell, James N.; McCurdy, Greg

    1992-09-01

    The establishment of lunar bases will not end the need for remote sensing of the lunar surface by orbiting platforms. Human and robotic surface exploration will necessarily be limited to some proximate distance from the support base. Near real-time, high-resolution, global characterization of the lunar surface by orbiting sensing systems will continue to be essential to the understanding of the Moon's geophysical structure and the location of exploitable minerals and deposits of raw materials. The Lunar Orbital Prospector (LOP) is an orbiting sensing platform capable of supporting a variety of modular sensing packages. Serviced by a lunar-based shuttle, the LOP will permit the exchange of instrument packages to meet evolving mission needs. The ability to recover, modify, and rotate sensing packages allows their reuse in varying combinations. Combining this flexibility with robust orbit modification capabilities and near real-time telemetry links provides considerable system responsiveness. Maintenance and modification of the LOP orbit are accomplished through use of an onboard propulsion system that burns lunar-supplied oxygen and aluminum. The relatively low performance of such a system is more than compensated for by the elimination of the need for Earth-supplied propellants. The LOP concept envisions a continuous expansion of capability through the incorporation of new instrument technologies and the addition of platforms.

  13. Imaging findings of the orbital and intracranial complications of acute bacterial rhinosinusitis.

    Science.gov (United States)

    Dankbaar, J W; van Bemmel, A J M; Pameijer, F A

    2015-10-01

    In patients with acute bacterial rhinosinusitis severe orbital and intracranial complications can occur. This review will illustrate the anatomic relationship between the paranasal sinuses and the orbital and intracranial compartments. Subsequently, the spectrum of orbital and intracranial complications of rhinosinusitis and related imaging findings will be discussed and illustrated by case material from daily practice. • Acute bacterial rhinosinusitis can cause severe orbital and intracranial complications. • If orbital or intracranial complications are suspected, cross-sectional imaging is mandatory. • Infection can spread from the ethmoid sinus to the orbit through the lamina papyracea. • Frontal sinusitis can spread intracranially through dehiscences or osteomyelitis. • Radiologists must recognize imaging findings of complications of acute bacterial rhinosinusitis.

  14. Averaging theory at any order for computing periodic orbits

    OpenAIRE

    Giné, Jaume

    2013-01-01

    We provide a recurrence formula for the coefficients of the powers of ε in the series expansion of the solutions around ε=0 of the perturbed first-order differential equations. Using it, we give an averaging theory at any order in εε for the following two kinds of analytic differential equation: A planar polynomial differential system with a singular point at the origin can be transformed, using polar coordinates, to an equation of the previous form. Thus, we apply our results for studying th...

  15. Picard Trajectory Approximation Iteration for Efficient Orbit Propagation

    Science.gov (United States)

    2015-07-21

    AFRL-OSR-VA-TR-2015-0203 Picard Trajectory Approximation Iteration for Efficient Orbit Propagation John Junkins TEXAS ENGINEERING EXPERIMENT STATION...Junkins, J., “Terminal Convergence Approximation Modified Chebyshev Picard Iteration for Efficient Numerical Integration of Orbital Trajectories ...problem, separated by an orbital period (these differ only in sign and along a particular Keplerian u trajectory , these sign switches occur when the

  16. [Viral load test conducive to excluding negative subjects from suspects in HIV antibody detections].

    Science.gov (United States)

    Hei, Fa-Xin; Zhang, Qi-Yun; Sun, Wei-Dong; Zhang, Qin; Ye, Jing-Rong; Liu, Hai-Lin; Lu, Hong-Yan

    2008-01-01

    To study whether plasma viral load testing is helpful to exclude ones free from Human immunodeficiency virus (HIV) infections from suspects in HIV antibody detections. 19 Specimens, which showed disconcordant results of the two HIV EIA testing (S/CO test, were selected. Viral load of the specimens were detected. A six-month follow up survey in detecting HIV antibody was conducted in these subjects. None of these 19 cases was observed to be positive HIV viral loads and there was no any progress in WB bands development during the follow-up period. The possibility of HIV infection could be excluded. When the specimens react with very low intensity in both EIA and WB, negative viral load result is conducive to exclude negative subjects from suspects in HIV antibody detections.

  17. Neurological signs in 23 dogs with suspected rostral cerebellar ischaemic stroke

    DEFF Research Database (Denmark)

    Thomsen, Barbara Blicher; Garosi, Laurent; Skerritt, Geoff

    2016-01-01

    Background: In dogs with ischaemic stroke, a very common site of infarction is the cerebellum. The aim of this study was to characterise neurological signs in relation to infarct topography in dogs with suspected cerebellar ischaemic stroke and to report short-term outcome confined...... to the hospitalisation period. A retrospective multicentre study of dogs with suspected cerebellar ischaemic stroke examined from 2010–2015 at five veterinary referral hospitals was performed. Findings from clinical, neurological, and paraclinical investigations including magnetic resonance imaging were assessed....... Results: Twenty-three dogs, 13 females and 10 males with a median age of 8 years and 8 months, were included in the study. The Cavalier King Charles Spaniel (n = 9) was a commonly represented breed. All ischaemic strokes were located to the vascular territory of the rostral cerebellar artery including...

  18. Suspect aggression and victim resistance in multiple perpetrator rapes.

    Science.gov (United States)

    Woodhams, Jessica; Cooke, Claire

    2013-11-01

    Several research studies have reported an elevated level of aggression in rapes committed by multiple perpetrators compared to rapes committed by lone suspects. Several factors that have been linked to elevated aggression in generic samples of rape were examined for the first time with a sample of multiple perpetrator rapes. Factors that might be associated with victim resistance were also investigated. Victim and offender characteristics, as well as the behaviors displayed by victims and offenders, were extracted from the police files of 89 multiple perpetrator stranger rapes perpetrated against female victims in the United Kingdom. These behaviors were rated for their level of suspect (non-sexual) aggression and victim resistance, respectively. Degree of victim resistance was significantly and positively associated with suspect aggression. Older victims were the recipients of significantly higher levels of suspect aggression. Victims who were incapacitated from drugs and/or alcohol were less likely to be the recipients of suspect aggression. Group leaders displayed more aggression towards the victim than the followers in the groups. The number of perpetrators was significantly related to the degree of resistance displayed by the victim with offences perpetrated by fewer suspects being characterized by more victim resistance. Research regarding cognitive appraisal during criminal interactions and the respective roles of offenders is referred to in considering these relationships.

  19. Interviewing strategically to elicit admissions from guilty suspects.

    Science.gov (United States)

    Tekin, Serra; Granhag, Pär Anders; Strömwall, Leif; Giolla, Erik Mac; Vrij, Aldert; Hartwig, Maria

    2015-06-01

    In this article we introduce a novel interviewing tactic to elicit admissions from guilty suspects. By influencing the suspects' perception of the amount of evidence the interviewer holds against them, we aimed to shift the suspects' counterinterrogation strategies from less to more forthcoming. The proposed tactic (SUE-Confrontation) is a development of the Strategic Use of Evidence (SUE) framework and aims to affect the suspects' perception by confronting them with statement-evidence inconsistencies. Participants (N = 90) were asked to perform several mock criminal tasks before being interviewed using 1 of 3 interview techniques: (a) SUE-Confrontation, (b) Early Disclosure of Evidence, or (c) No Disclosure of Evidence. As predicted, the SUE-Confrontation interview generated more statement-evidence inconsistencies from suspects than the Early Disclosure interview. Importantly, suspects in the SUE-Confrontation condition (vs. Early and No disclosure conditions) admitted more self-incriminating information and also perceived the interviewer to have had more information about the critical phase of the crime (the phase where the interviewer lacked evidence). The findings show the adaptability of the SUE-technique and how it may be used as a tool for eliciting admissions. (c) 2015 APA, all rights reserved).

  20. [Orbital complications of sinusitis].

    Science.gov (United States)

    Šuchaň, M; Horňák, M; Kaliarik, L; Krempaská, S; Koštialová, T; Kovaľ, J

    2014-12-01

    Orbital complications categorised by Chandler are emergency. They need early diagnosis and agresive treatment. Stage and origin of orbital complications are identified by rhinoendoscopy, ophtalmologic examination and CT of orbite and paranasal sinuses. Periorbital cellulitis and early stage of orbital cellulitis can be treated conservatively with i. v. antibiotics. Monitoring of laboratory parameters and ophtalmologic symptoms is mandatory. Lack of improvement or worsening of symptoms within 24-48 hours and advanced stages of orbital complications are indicated for surgery. The purpose of the study is to evaluate epidemiology, clinical features and management of sinogenic orbital complications. Retrospective data of 8 patients with suspicion of orbital complication admited to hospital from 2008 to 2013 were evaluated. Patients were analyzed in terms of gender, age, CT findings, microbiology, clinical features, stage and treatment. Male and female were afected in rate 1,66:1. Most of patients were young adult in 3rd. and 4th. decade of life (62,5 %). Acute and chronic sinusitis were cause of orbital complication in the same rate. The most common origin of orbital complication was ethmoiditis (62,5 %), than maxillary (25 %) and frontal (12,5 %) sinusitis. Polysinusitis with affection of ethmoidal, maxillary and frontal sinuses (75 %) was usual CT finding. Staphylococcus epidermidis and Staphylococcus aureus were etiological agens in half of cases. Periorbital oedema (100 %), proptosis, chemosis (50 %), diplopia and glaucoma (12,5 %) were observed. Based on examinations, diagnosis of periorbital oedema/preseptal cellulitis was made in 3 (37,5 %), orbital cellulitis in 3 (37,5 %) and subperiosteal abscess in 2 cases (25 %). All patients underwent combined therapy - i. v. antibiotics and surgery within 24 hours. Eradication of disease from ostiomeatal complex (OMC), drainage of affected sinuses and drainage of subperiosteal abscess were done via fuctional endonasal

  1. Suspected citrus pulp toxicosis in dairy cattle.

    Science.gov (United States)

    Saunders, G K; Blodgett, D J; Hutchins, T A; Prater, R M; Robertson, J L; Friday, P A; Scarratt, W K

    2000-05-01

    Thirteen lactating dairy cows from a herd of 650 died over a 6-week period. Most animals were down in milk production at 1 milking and were found dead at the next milking. Two cows had elevated heart rate and enlarged mandibular lymph nodes. Two others had azotemia, elevated heart rate, hyperglycemia, and weight loss. Necropsy of 10 cows revealed hemorrhages on the intestinal serosa and epicardium, lymphadenopathy, interstitial nephritis, small intestinal hemorrhage, and interstitial pneumonia. Histopathology showed lymphocytic to lymphogranulomatous inflammation in the heart, spleen, kidney, lymph nodes, liver, lung, pancreas, and adrenal gland. Phlebitis was present in 2 livers. The lesions resembled those of hairy vetch toxicosis, but no vetch was being fed. Similar lesions have been reported with the feeding of citrus pulp. Citrus pulp was being fed to the lactating cows and had been added to the diet 6 weeks before the first death. The syndrome resolved with elimination of citrus pulp from the diet.

  2. Orbit Feedback Operation with RCBX (MD 1209)

    CERN Document Server

    Wenninger, Jorg; Nisbet, David; Ponce, Laurette; Louro Alves, Diogo Miguel; CERN. Geneva. ATS Department

    2017-01-01

    The LHC Orbit Feedback (OFB) is able to drive any orbit corrector circuit (COD) to steer the LHC orbit. But during the first feedback tests in 2010, all attempts to use the common triplet orbit correctors (MCBX) failed because the QPS system installed to protect those magnets triggered power aborts as soon as the OFB steered the beam with those CODs. The reason was most likely the violation of the RCBX circuit acceleration limits. For this reason the MCBX orbit correctors were never driven by the OFB in regular operation. Although the performance of the OFB is generally excellent, the quality of the beam steering around IRs could be improved if the OFB could correct the orbit with the MCBX to counteract locally triplet quadrupole movements. The aim of this MD was to make a new attempt to use the MCBX in the OFB. The test was successful at injection (no circuit trip) and failed during the ramp (QPS power abort). The PC voltages and QPS Ures signals revealed the presence of voltage spikes with a period of 10~s...

  3. ARTEMIS: The First Mission to the Lunar Libration Orbits

    Science.gov (United States)

    Woodward, Mark; Folta, David; Woodfork, Dennis

    2009-01-01

    The ARTEMIS mission will be the first to navigate to and perform stationkeeping operations around the Earth-Moon L1 and L2 Lagrangian points. The NASA Goddard Space Flight Center (GSFC) has previous mission experience flying in the Sun-Earth L1 (SOHO, ACE, WIND, ISEE-3) and L2 regimes (WMAP) and have maintained these spacecraft in libration point orbits by performing regular orbit stationkeeping maneuvers. The ARTEMIS mission will build on these experiences, but stationkeeping in Earth-Moon libration orbits presents new challenges since the libration point orbit period is on the order of two weeks rather than six months. As a result, stationkeeping maneuvers to maintain the Lissajous orbit will need to be performed frequently, and the orbit determination solutions between maneuvers will need to be quite accurate. The ARTEMIS mission is a collaborative effort between NASA GSFC, the University of California at Berkeley (UCB), and the Jet Propulsion Laboratory (JPL). The ARTEMIS mission is part of the THEMIS extended mission. ARTEMIS comprises two of the five THEMIS spacecraft that will be maneuvered from near-Earth orbits into lunar libration orbits using a sequence of designed orbital maneuvers and Moon & Earth gravity assists. In July 2009, a series of orbit-raising maneuvers began the proper orbit phasing of the two spacecraft for the first lunar flybys. Over subsequent months, additional propulsive maneuvers and gravity assists will be performed to move each spacecraft though the Sun-Earth weak stability regions and eventually into Earth-Moon libration point orbits. We will present the overall orbit designs for the two ARTEMIS spacecraft and provide analysis results of the 3/4-body dynamics, and the sensitivities of the trajectory design to both · maneuver errors and orbit determination errors. We will present results from the. initial orbit-raising maneuvers.

  4. Overview of suspected adverse reactions to veterinary medicinal products reported in South Africa (March 2002 – February 2003

    Directory of Open Access Journals (Sweden)

    V. Naidoo

    2003-07-01

    Full Text Available The Veterinary Pharmacovigilance and Medicines Information Centre is responsible for the monitoring of veterinary adverse drug reactions in South Africa. An overview of reports of suspected adverse drug reactions received by the centre during the period March 2002 to February 2003 is given. In total, 40 reports were received. This had declined from the previous year. Most reports involved suspected adverse reactions that occurred in dogs and cats. Most of the products implicated were Stock Remedies. The animal owner predominantly administered these products. Only 1 report was received from a veterinary pharmaceutical company. Increasing numbers of reports are being received from veterinarians.

  5. Presumed prevalence analysis on suspected and highly suspected breast cancer lesions in São Paulo using BIRADS® criteria

    Directory of Open Access Journals (Sweden)

    Vivian Milani

    Full Text Available CONTEXT AND OBJECTIVE: Breast cancer screening programs are critical for early detection of breast cancer. Early detection is essential for diagnosing, treating and possibly curing breast cancer. Since there are no data on the incidence of breast cancer, nationally or regionally in Brazil, our aim was to assess women by means of mammography, to determine the prevalence of this disease. DESIGN AND SETTING: The study protocol was designed in collaboration between the Department of Diagnostic Imaging (DDI, Institute of Diagnostic Imaging (IDI and São Paulo Municipal Health Program. METHODS: A total of 139,945 Brazilian women were assessed by means of mammography between April 2002 and September 2004. Using the American College of Radiology (ACR criteria (Breast Imaging Reporting and Data System, BIRADS®, the prevalence of suspected and highly suspected breast lesions were determined. RESULTS: The prevalence of suspected (BIRADS® 4 and highly suspected (BIRADS® 5 lesions increased with age, especially after the fourth decade. Accordingly, BIRADS® 4 and BIRADS® 5 lesions were more prevalent in the fourth, fifth, sixth and seventh decades. CONCLUSION: The presumed prevalence of suspected and highly suspected breast cancer lesions in the population of São Paulo was 0.6% and it is similar to the prevalence of breast cancer observed in other populations.

  6. A Tapestry of Orbits

    Science.gov (United States)

    King-Hele, D. G.

    2005-07-01

    Satellites as they cross the night sky look like moving stars, which can be accurately tracked by an observer with binoculars as well as by giant radars and large cameras. These observations help to determine the satellite's orbit, which is sensitive to the drag of the upper atmosphere and to any irregularities in the gravity field of the Earth. Analysis of the orbit can be used to evaluate the density of the upper atmosphere and to define the shape of the Earth. Desmond King-Hele was the pioneer of this technique of orbit analysis, and this book tells us how the research began, before the launch of Sputnik in 1957. For thirty years King-Hele and his colleagues at the Royal Aircraft Establishment, Farnborough, developed and applied the technique to reveal much about the Earth and air at a very modest cost. In the 1960s the upper-atmosphere density was thoroughly mapped out for 100 to 2000 km, revealing immense variation of density with solar activity and between day and night. In the 1970s and 1980s a picture of the upper-atmosphere winds emerged, and the profile of the pear-shaped Earth was accurately charted. The number of satellites now orbiting the earth is over 5000. This book is the story of how this inexpensive research of their orbits developed to yield a rich harvest of knowledge about the Earth and its atmosphere, in a scientific narrative that is enlivened with many personal experiences.

  7. Satellite Orbital Precessions Caused by the Octupolar Mass Moment ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... I consider a satellite moving around a non-spherical body of mass and equatorial radius , and calculate its orbital precessions caused by the body's octupolar mass moment 4. I consider only the effects averaged over one orbital period of the satellite. I give exact formulas, not restricted to any special ...

  8. Extended duration orbiter (EDO) insignia

    Science.gov (United States)

    1990-01-01

    Extended duration orbiter (EDO) insignia incorporates a space shuttle orbiter with payload bay doors (PLBDs) open and a spacelab module inside. Trailing the orbiter are the initials EDO. The EDO-modified Columbia, Orbiter Vehicle (OV) 102, will be flown for the first EDO mission, STS-50.

  9. Relative motion of orbiting bodies

    Science.gov (United States)

    Butikov, Eugene I.

    2001-01-01

    A problem of relative motion of orbiting bodies is investigated on the example of the free motion of any body ejected from the orbital station that stays in a circular orbit around the earth. An elementary approach is illustrated by a simulation computer program and supported by a mathematical treatment based on approximate differential equations of the relative orbital motion.

  10. Elliptical Orbit Performance Computer Program

    Science.gov (United States)

    Myler, T.

    1984-01-01

    Elliptical Orbit Performance (ELOPE) computer program for analyzing orbital performance of space boosters uses orbit insertion data obtained from trajectory simulation to generate parametric data on apogee and perigee altitudes as function of payload data. Data used to generate presentation plots that display elliptical orbit performance capability of space booster.

  11. PERIODIC BEHAVIORS

    NARCIS (Netherlands)

    Napp, Diego; Put, Marius van der; Shankar, Shiva

    2010-01-01

    This paper studies behaviors that are defined on a torus, or equivalently, behaviors defined in spaces of periodic functions, and establishes their basic properties analogous to classical results of Malgrange, Palamodov, Oberst et al. for behaviors on R(n). These properties-in particular the

  12. Raccoon eyes and the MIBG super scan: scintigraphic signs of neuroblastoma in a case of suspected child abuse

    Energy Technology Data Exchange (ETDEWEB)

    Bohdiewicz, P.J. [Nuclear Medicine Dept., William Beaumont Hospital, Royal Oak, MI (United States); Gallegos, E. [Nuclear Medicine Dept., William Beaumont Hospital, Royal Oak, MI (United States); Fink-Bennett, D. [Nuclear Medicine Dept., William Beaumont Hospital, Royal Oak, MI (United States)

    1995-11-01

    The authors report on an infant suspected of having been abused, who presented with periorbital edema and ecchymoses (clinial `raccoon eyes`). The pattern of the nuclear medicine bone scan suggested neuroblastoma rather than trauma. Both the bone scan and the subsequent MIBG scan revealed multiple abnormalities, including markedly increased activity around the orbits, that we termed the `scintigraphic raccoon eyes` sign. In addition, the grossly abnormal MIBG scan demonstrated avid uptake of MIBG throughout the entire skeleton with essentially complete absence of visualization of the liver and heart (the `MIBG super scan`). These signs have not previously been described in an infant or a child with neuroblastoma. (orig.)

  13. Period Variations of RT Persei

    Directory of Open Access Journals (Sweden)

    Chun-Hwey Kim

    1995-12-01

    Full Text Available RT Per has been known as a close binary of which the orbital period has unpredictably varied so far. Although there are no agreements with the working mechanism for the changes of the period, two interpretations have been suggested and waiting for to be tested: 1light-time effects due to the unseen 3rd and 4th bodies (Panchatsaram 1981, 2Abrupt period-change due to internal variations of the system(e.q. mass transfer or mass loss superimposing to the light-times effect by a 3rd body (Frieboes-Conde & Herczeg 1973. In the point of view that the former interprepation models could predict the behavior of the changes of the orbital period theoretically, we checked whether the recent observed times of minimum lights follow the predictions by the first model or not. We confirmed that the observed times of minimum lights have followed the variations calculated by the light-times effects due to 3rd and 4th bodies suggested by Panchatsaram. In this paper a total of 626 times of minimum lights were reanalyzed in terms of the light-time effects by the 3rd and 4th bodies. We concluded that the eclipsing pair in SV Cam system moves in an elliptic orbit about center of mass of the triple system with a period of about 42.y2, while the mass center of the triplet is in light-time orbit about the center of mass of the quadruple system with a period of 120y. The mean masses deduced for the 3rd and 4th bodies were 0.89m⨀ and 0.82m⨀, respectively.

  14. [Secondary orbital lymphoma].

    Science.gov (United States)

    Basanta, I; Sevillano, C; Álvarez, M D

    2015-09-01

    A case is presented of an 85 year-old Caucasian female with lymphoma that recurred in the orbit (secondary ocular adnexal lymphoma). The orbital tumour was a diffuse large B-cell lymphoma according to the REAL classification (Revised European-American Lymphoma Classification). Orbital lymphomas are predominantly B-cell proliferations of a variety of histological types, and most are low-grade tumours. Patients are usually middle-aged or elderly, and it is slightly more common in women. A palpable mass, proptosis and blepharoptosis are the most common signs of presentation. Copyright © 2011 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  15. Preseptal Cellulitis Or Orbital Cellulitis?

    Science.gov (United States)

    Lim, L T; Miller, D; Ah-Kee, E Y; Ferguson, A

    2015-06-29

    Preseptal cellulitis and orbital cellulitis can both present with increasing swelling, tenderness and redness around the eye, but their management differs. Preseptal cellulitis is more common and much less aggressive than orbital cellulitis. In contrast, orbital cellulitis is a medical emergency requiring urgent management. In this article, we provide a systematic approach to distinguish between preseptal cellulitis and orbital cellulitis at presentation, as the distinction between the two entities and the prompt recognition of orbital cellulitis can be potentially life-saving.

  16. Preliminary orbit determination

    Science.gov (United States)

    Taff, L. G.; Belkin, B.; Schweiter, G.; Sommar, K.

    The problem of intercontinental ballistic missile reentry vehicle orbit determination from incomplete passive (i.e., angles-only) or active (i.e., distance plus angles) information is presented. Launch location and time and impact location and time to complete the computation of an orbital element set are utilized. In addition, it is possible to construct a good estimate of the variance of the key quantity in the angles only case; namely the computed topocentric distance. This type of observation/information situation is enlarged to include a complete discussion of single-point differential correction.

  17. Pediatric Orbital Fractures

    Science.gov (United States)

    Oppenheimer, Adam J.; Monson, Laura A.; Buchman, Steven R.

    2013-01-01

    It is wise to recall the dictum “children are not small adults” when managing pediatric orbital fractures. In a child, the craniofacial skeleton undergoes significant changes in size, shape, and proportion as it grows into maturity. Accordingly, the craniomaxillofacial surgeon must select an appropriate treatment strategy that considers both the nature of the injury and the child's stage of growth. The following review will discuss the management of pediatric orbital fractures, with an emphasis on clinically oriented anatomy and development. PMID:24436730

  18. Satellite orbit predictor

    Science.gov (United States)

    Friedman, Morton l.; Garrett, James, Major

    An analog aid to determine satellite coverage of Emergency Locator Transmitters Emergency Position Indicating Radio Beacon (ELT/EPIRB) distress incidence is discussed. The satellite orbit predictor is a graphical aid for determining the relationship between the satellite orbit, antenna coverage of the spacecraft and coverage of the Local User Terminal. The predictor allows the user to quickly visualize if a selected position will probably be detected and is composed of a base map and a satellite track overlay for each satellite.A table of equator crossings for each satellite is included.

  19. Period Variations of RT Persei

    OpenAIRE

    Chun-Hwey Kim

    1995-01-01

    RT Per has been known as a close binary of which the orbital period has unpredictably varied so far. Although there are no agreements with the working mechanism for the changes of the period, two interpretations have been suggested and waiting for to be tested: 1)light-time effects due to the unseen 3rd and 4th bodies (Panchatsaram 1981), 2)Abrupt period-change due to internal variations of the system(e.q. mass transfer or mass loss) superimposing to the light-times effect by a 3rd body (Frie...

  20. Patch testing in Israeli children with suspected allergic contact dermatitis: A retrospective study and literature review.

    Science.gov (United States)

    Zafrir, Yaron; Trattner, Akiva; Hodak, Emmillia; Eldar, Oren; Lapidoth, Moshe; Ben Amitai, Dan

    2017-11-16

    Childhood allergic contact dermatitis is recognized as a significant clinical problem. The objective was to evaluate the rate of positive patch tests in Israeli children with clinically suspected allergic contact dermatitis, identify possible sex and age differences, compare results with those in Israeli adults, and review pediatric studies in the literature. The study sample included 343 children and adolescents (197 female, 146 male; 1-18 years of age, mean age 11.8 years) with clinically suspected allergic contact dermatitis who underwent patch testing with a standard pediatric series of 23 allergens at a tertiary medical center from 1999 to 2012. Data on clinical characteristics and test results were collected retrospectively from the medical files. Ninety-eight subjects (28.6%) (75 girls [38.1%], 23 boys [15.8%]) had at least one positive reaction. The most frequent reactions were to nickel sulfate, followed by potassium dichromate and cobalt chloride. Nickel sulfate sensitivity was more common in girls, especially those younger than 3 years and older than 12 years. The prevalence of contact sensitization was similar in subjects with and without atopic dermatitis (50% and 51%, respectively). Nickel is the most common allergen in Israeli children, especially girls. Patch testing should be performed in children with clinically suspected allergic contact dermatitis regardless of atopic background. © 2017 Wiley Periodicals, Inc.

  1. Detection of herpes viruses in the cerebrospinal fluid of adults with suspected viral meningitis in Malawi.

    Science.gov (United States)

    Benjamin, L A; Kelly, M; Cohen, D; Neuhann, F; Galbraith, S; Mallewa, M; Hopkins, M; Hart, I J; Guiver, M; Lalloo, D G; Heyderman, R S; Solomon, T

    2013-02-01

    We looked for herpes simplex virus types 1 and 2 (HSV-1 and HSV-2, respectively), varicella zoster virus (VZV), Epstein-Barr virus (EBV) and cytomegalovirus (CMV) DNA in Malawian adults with clinically suspected meningitis. We collected cerebrospinal fluid (CSF) from consecutive adults admitted with clinically suspected meningitis to Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi, for a period of 3 months. Those with proven bacterial or fungal meningitis were excluded. Real-time polymerase chain reaction (PCR) was performed on the CSF for HSV-1 and HSV-2, VZV, EBV and CMV DNA. A total of 183 patients presented with clinically suspected meningitis. Of these, 59 (32 %) had proven meningitis (bacterial, tuberculous or cryptococcal), 39 (21 %) had normal CSF and 14 (8 %) had aseptic meningitis. For the latter group, a herpes virus was detected in 9 (64 %): 7 (50 %) had EBV and 2 (14 %) had CMV, all were human immunodeficiency virus (HIV)-positive. HSV-2 and VZV were not detected. Amongst those with a normal CSF, 8 (21 %) had a detectable herpes virus, of which 7 (88 %) were HIV-positive. The spectrum of causes of herpes viral meningitis in this African population is different to that in Western industrialised settings, with EBV being frequently detected in the CSF. The significance of this needs further investigation.

  2. GALILEO ORBITER JUPITER RAW MAGNETOMETER DATA V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains raw magnetic field data acquired by the Galileo Orbiter magnetometer at Jupiter. The data set covers the time period from 1995-11-06T00:21:30...

  3. Frozen orbits at high eccentricity and inclination: application to Mercury orbiter

    Science.gov (United States)

    Delsate, N.; Robutel, P.; Lemaître, A.; Carletti, T.

    2010-11-01

    We hereby study the stability of a massless probe orbiting around an oblate central body (planet or planetary satellite) perturbed by a third body, assumed to lay in the equatorial plane (Sun or Jupiter for example) using a Hamiltonian formalism. We are able to determine, in the parameters space, the location of the frozen orbits, namely orbits whose orbital elements remain constant on average, to characterize their stability/unstability and to compute the periods of the equilibria. The proposed theory is general enough, to be applied to a wide range of probes around planet or natural planetary satellites. The BepiColombo mission is used to motivate our analysis and to provide specific numerical data to check our analytical results. Finally, we also bring to the light that the coefficient J 2 is able to protect against the increasing of the eccentricity due to the Kozai-Lidov effect and the coefficient J 3 determines a shift of the equilibria.

  4. Economic evaluation of a clinical protocol for diagnosing emergency patients with suspected pulmonary embolism

    Directory of Open Access Journals (Sweden)

    Wolfe Rory

    2006-06-01

    Full Text Available Abstract Background The objective of this paper is to estimate the amount of cost-savings to the Australian health care system from implementing an evidence-based clinical protocol for diagnosing emergency patients with suspected pulmonary embolism (PE at the Emergency department of a Victorian public hospital with 50,000 presentations in 2001–2002. Methods A cost-minimisation study used the data collected in a controlled clinical trial of a clinical protocol for diagnosing patients with suspected PE. Thenumber and type of diagnostic tests in a historic cohort of 185 randomly selected patients, who presented to the emergency department with suspectedPE during an eight month period prior to the clinical trial (January 2002 -August 2002 were compared with the number and type of diagnostic tests in745 patients, who presented to the emergency department with suspected PE from November 2002 to August 2003. Current Medicare fees per test were usedas unit costs to calculate the mean aggregated cost of diagnostic investigation per patient in both study groups. A t-test was used to estimate the statistical significance of the difference in the cost of resources used for diagnosing PE in the control and in the intervention group. Results The trial demonstrated that diagnosing PE using an evidence-based clinical protocol was as effective as the existing clinical practice. The clinical protocol offers the advantage of reducing the use of diagnostic imaging, resulting in an average cost savings of at least $59.30 per patient. Conclusion Extrapolating the observed cost-savings of $59.30 per patient to the wholeof Australia could potentially result in annual savings between $3.1 million to $3.7 million.

  5. Investigations of SPS Orbit Drifts

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-07-01

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

  6. Investigations of SPS orbit drifts

    CERN Document Server

    Drøsdal, L; Cornelis, K; Goddard, B; Kain, V; Meddahi, M; Wenninger, J; Gianfelice-Wendt, E

    2014-01-01

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

  7. The Lunar orbit paradox

    Directory of Open Access Journals (Sweden)

    Tomić Aleksandar S.

    2013-01-01

    Full Text Available Newton's formula for gravity force gives greather force intensity for atraction of the Moon by the Sun than atraction by the Earth. However, central body in lunar (primary orbit is the Earth. So appeared paradox which were ignored from competent specialist, because the most important problem, determination of lunar orbit, was inmediately solved sufficiently by mathematical ingeniosity - introducing the Sun as dominant body in the three body system by Delaunay, 1860. On this way the lunar orbit paradox were not canceled. Vujičić made a owerview of principles of mechanics in year 1998, in critical consideration. As an example for application of corrected procedure he was obtained gravity law in some different form, which gave possibility to cancel paradox of lunar orbit. The formula of Vujičić, with our small adaptation, content two type of acceleration - related to inertial mass and related to gravity mass. So appears carried information on the origin of the Moon, and paradox cancels.

  8. Myxoma of the orbit.

    Directory of Open Access Journals (Sweden)

    Rambhatla Saptagirish

    2003-01-01

    Full Text Available Myxomas are rare, benign neoplasms of mesenchymal origin that usually develop in soft tissues. As the clinical manifestations are non-specific, it is difficult to diagnose the tumour without biopsy and histopathological examination. We report a case of orbital myxoma with histopathological correlation.

  9. A Neptune Orbiter Mission

    Science.gov (United States)

    Wallace, R. A.; Spilker, T. R.

    1998-01-01

    This paper describes the results of new analyses and mission/system designs for a low cost Neptune Orbiter mission. Science and measurement objectives, instrumentation, and mission/system design options are described and reflect an aggressive approach to the application of new advanced technologies expected to be available and developed over the next five to ten years.

  10. Persistence of homoclinic orbits for billiards and twist maps

    CERN Document Server

    Bolotin, S; Ramírez-Ros, R

    2003-01-01

    We consider the billiard motion inside a C2-small perturbation of a n-dimensional ellipsoid Q with a unique major axis. The diameter of the ellipsoid Q is a hyperbolic two-periodic trajectory whose stable and unstable invariant manifolds are doubled, so that there is a n-dimensional invariant set W of homoclinic orbits for the unperturbed billiard map. The set W is a stratified set with a complicated structure. For the perturbed billiard map the set W generically breaks down into isolated homoclinic orbits. We provide lower bounds for the number of primary homoclinic orbits of the perturbed billiard which are close to unperturbed homoclinic orbits in certain strata of W. The lower bound for the number of persisting primary homoclinic billiard orbits is deduced from a more general lower bound for exact perturbations of twist maps possessing a manifold of homoclinic orbits.

  11. Analysis of the orbital motion of the asteroid Apophis' satellite

    Science.gov (United States)

    Ivashkin, V. V.; Lang, A.

    2017-07-01

    We have analyzed the orbital disturbed spacecraft motion near an asteroid. The equations of the asteroidocentric spacecraft motion have been used with regard to three perturbations from celestial bodies, the asteroid's nonsphericity, and solar radiation pressure. It has been shown that the orbital parameters of the main spacecraft and a small satellite with a radio beacon can be selected such that the orbits are rather stable for a fairly long period of time, i.e., a few weeks for the main spacecraft with an orbit initial radius of 0.5 km and a few years before approaching Apophis with the Earth in 2029, for a small satellite at an orbit initial radius of 1.5 km. The initial orientation of the spacecraft orbital plane perpendicular to the sunward direction is optimal from the point of view of the stability of the spacecraft flight near an asteroid.

  12. The use of psychoactive prescription drugs among DUI suspects.

    Science.gov (United States)

    Karjalainen, Karoliina; Haukka, Jari; Lintonen, Tomi; Joukamaa, Matti; Lillsunde, Pirjo

    2015-10-01

    The study seeks to increase understanding of the use of psychoactive prescription drugs among persons suspected of driving under the influence (DUI). We studied whether the use of prescribed psychoactive medication was associated with DUI, and examined the difference in the use of prescription drugs between DUI recidivists and those arrested only once. In this register-based study, persons suspected of DUI (n=29470) were drawn from the Register of DUI suspects, and an age- and gender-matched reference population (n=30043) was drawn from the Finnish general population. Data on prescription drug use was obtained by linkage to the National Prescription Register. The associations of DUI arrest and use of psychoactive prescription drugs in different DUI groups (findings for alcohol only, prescription drugs, prescription drugs and alcohol, illicit drugs) were estimated by using mixed-effect logistic regression. The use of psychoactive prescription drugs and DUI appeared to be strongly associated, with DUI suspects significantly more likely to use psychoactive prescription drugs compared to the reference population. Gender differences existed, with the use of benzodiazepines being more common among female DUI suspects. Moreover, DUI recidivists were more likely to use psychoactive prescription drugs compared to those arrested only once. In addition to alcohol and/or illicit drug use, a significant proportion of DUI suspects were using psychoactive prescription drugs. When prescribing psychoactive medication, especially benzodiazepines, physicians are challenged to screen for possible substance use problems and also to monitor for patients' alcohol or illicit drug use while being medicated. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Book Review: Placing the Suspect behind the Keyboard: Using Digital Forensics and Investigative Techniques to Identify Cybercrime Suspects

    Directory of Open Access Journals (Sweden)

    Thomas Nash

    2013-06-01

    Full Text Available Shavers, B. (2013. Placing the Suspect behind the Keyboard: Using Digital Forensics and Investigative Techniques to Identify Cybercrime Suspects. Waltham, MA: Elsevier, 290 pages, ISBN-978-1-59749-985-9, US$51.56. Includes bibliographical references and index.Reviewed by Detective Corporal Thomas Nash (tnash@bpdvt.org, Burlington Vermont Police Department, Internet Crime against Children Task Force. Adjunct Instructor, Champlain College, Burlington VT.In this must read for any aspiring novice cybercrime investigator as well as the seasoned professional computer guru alike, Brett Shaver takes the reader into the ever changing and dynamic world of Cybercrime investigation.  Shaver, an experienced criminal investigator, lays out the details and intricacies of a computer related crime investigation in a clear and concise manner in his new easy to read publication, Placing the Suspect behind the Keyboard. Using Digital Forensics and Investigative techniques to Identify Cybercrime Suspects. Shaver takes the reader from start to finish through each step of the investigative process in well organized and easy to follow sections, with real case file examples to reach the ultimate goal of any investigation: identifying the suspect and proving their guilt in the crime. Do not be fooled by the title. This excellent, easily accessible reference is beneficial to both criminal as well as civil investigations and should be in every investigator’s library regardless of their respective criminal or civil investigative responsibilities.(see PDF for full review

  14. Suspected Rhinolithiasis Associated With Endodontic Disease in a Cat.

    Science.gov (United States)

    Ng, Kevin; Fiani, Nadine; Peralta, Santiago

    2017-12-01

    Rhinoliths are rare, intranasal, mineralized masses formed via the precipitation of mineral salts around an intranasal nidus. Clinical signs are typically consistent with inflammatory rhinitis and nasal obstruction, but asymptomatic cases are possible. Rhinoliths may be classified as exogenous or endogenous depending on the origin of the nidus, with endogenous rhinoliths reportedly being less common. This case report describes a suspected case of endogenous rhinolithiasis in a cat which was detected as an incidental finding during radiographic assessment of a maxillary canine tooth with endodontic disease. Treatment consisted of removal of the suspected rhinolith via a transalveolar approach after surgical extraction of the maxillary canine tooth.

  15. Cholescintigraphy and ultrasonography in patients suspected of having acute cholecystitis

    DEFF Research Database (Denmark)

    Lauritsen, K B; Sommer, W; Hahn, L

    1988-01-01

    The diagnostic power of combined cholescintigraphy and ultrasonography was tested in 67 patients suspected of having acute cholecystitis; of these, 42 (63%) had acute cholecystitis. The predictive value of a positive scintigraphy (PVpos) was 95% and that of a negative (PVneg) was 91% (n = 67...... that in patients suspected of having acute cholecystitis cholescintigraphy should be the first diagnostic procedure performed. If the scintigraphy is positive, additional ultrasonographic detection of gallstones makes the diagnosis almost certain. If one diagnostic modality is inconclusive, the other makes a fair...

  16. Symptomatic Patency Capsule Retention in Suspected Crohn's Disease

    DEFF Research Database (Denmark)

    Rasmussen, Bjørn; Nathan, Torben; Jensen, Michael Dam

    2016-01-01

    The main limitation of capsule endoscopy is the risk of capsule retention. In patients with suspected Crohn's disease, however, this complication is rare, and if a small bowel stenosis is not reliably excluded, small bowel patency can be confirmed with the Pillcam patency capsule. We present two...... patients examined for suspected Crohn's disease who experienced significant symptoms from a retained patency capsule. Both patients had Crohn's disease located in the terminal ileum. In one patient, the patency capsule caused abdominal pain and vomiting and was visualized at magnetic resonance enterography...

  17. Orbital invasion by periocular basal cell carcinoma.

    Science.gov (United States)

    Leibovitch, Igal; McNab, Alan; Sullivan, Timothy; Davis, Garry; Selva, Dinesh

    2005-04-01

    To present a large series of patients with orbital invasion by periocular basal cell carcinoma (BCC). Retrospective, noncomparative, interventional case series. All cases diagnosed with orbital invasion by periocular BCC between January 1985 and July 2004 in 3 Orbital Units in Australia. The clinical records of all patients were reviewed. Patients' demographics, clinical presentation, histologic subtypes, treatment modalities, recurrence rate, and tumor-related death. There were 64 patients (49 males) with a mean age of 70+/-13 years. Most tumors (84.4%) were recurrent or previously incompletely excised, and the medial canthus was most frequently involved (56.2%). Signs suggestive of orbital involvement included a mass with bone fixation (35.7%), limitation of ocular motility (30.4%), and globe displacement (17.6%). There were no signs suggestive of orbital invasion in 35.7%. Most patients (51.6%) had infiltrative histologic findings, and perineural invasion was present in 19.3%. Treatment modalities were mainly exenteration alone or combined with radiotherapy. During a mean follow-up period of 3.6 years, 3 cases of recurrence (4.7%) were diagnosed. Only 1 patient (1.6%) died from tumor-related causes. Orbital invasion by periocular BCC is an uncommon event that may be associated with significant ocular morbidity and, rarely, death. Because orbital invasion may often be clinically silent, clinicians need to be alert to the possibility in high-risk tumors and consider appropriate imaging. Surgical treatment with exenteration or excision, with or without radiotherapy, results in a low recurrence and mortality rate.

  18. Mature teratoma presenting as orbital cellulitis in a 5-month-old baby.

    Science.gov (United States)

    Alkatan, Hind Manaa; Chaudhry, Imtiaz; Alayoubi, Ayman

    2013-01-01

    We have presented an interesting case of an unexpected orbital tumor in a 5-month-old female healthy baby who presented initially with a 1-week history of acute left proptosis, swollen eyelid, conjunctival chemosis and exposure keratopathy. She was treated with intravenous antibiotics without any improvement and was referred for the drainage of the left orbital abscess. The procedure was performed with partial resolution, however the proptosis persisted and an underlying orbital pathologic lesion was suspected. Further exploring the left orbital revealed a partially cystic tumor. The histopathologic features were consistent with a mature teratoma. The case is presented with a brief discussion on this entity to attract the attention of general ophthalmologists to such tumors in the orbit.

  19. Modification of an impulse-factoring orbital transfer technique to account for orbit determination and maneuver execution errors

    Science.gov (United States)

    Kibler, J. F.; Green, R. N.; Young, G. R.; Kelly, M. G.

    1974-01-01

    A method has previously been developed to satisfy terminal rendezvous and intermediate timing constraints for planetary missions involving orbital operations. The method uses impulse factoring in which a two-impulse transfer is divided into three or four impulses which add one or two intermediate orbits. The periods of the intermediate orbits and the number of revolutions in each orbit are varied to satisfy timing constraints. Techniques are developed to retarget the orbital transfer in the presence of orbit-determination and maneuver-execution errors. Sample results indicate that the nominal transfer can be retargeted with little change in either the magnitude (Delta V) or location of the individual impulses. Additonally, the total Delta V required for the retargeted transfer is little different from that required for the nominal transfer. A digital computer program developed to implement the techniques is described.

  20. a Three-Dimensional Orbit for Capella

    Science.gov (United States)

    Branham, Richard L.

    2008-09-01

    Semidefinite programming is applied to 169 interferometric observations of Capella, made between 1919 and 1999, and 221 double-line radial velocities, obtained between 1896 and 1991, to calculate a three-dimensional orbit. The data are reduced with the robust L 1 criterion. The orbit is nearly circular, eccentricity of 0.00508, with a semimajor axis of 0farcs056 and period of 104.039 days. The mass of the primary is calculated to be 3.049 M sun, that of the secondary 2.569 M sun, and the parallax of the system is calculated to be 74.85 mas. Another orbit is calculated, but using only the best data, Mark III interferometric observations, and Coralie radial velocities. Although the mean errors for this orbit are considerably smaller, reasons are given for preferring the orbit calculated from all of the data as opposed to only the best data: the residuals are more random, the parallax agrees better with van Leeuwen's re-reduction of the Hipparcos parallax, and the Shannon uncertainty is lower.

  1. Orbital and intracranial complications after acute rhinosinusitis.

    Science.gov (United States)

    Kastner, Jan; Taudy, Milos; Lisy, Jiri; Grabec, Paul; Betka, Jan

    2010-12-01

    Nowadays, intracranial abscess is a rare complication of acute rhinosinusitis. The consequent orbital and intracranial complications of acute rhinosinusitis are rare but must be mutually excluded in complicated rhinosinusitis even when proper surgical and medical treatment tend to efficiently heal the orbital complication. We report a case of a patient who primarily revealed symptoms of orbitocellulitis as a complication of odontogenous rhinosinusitis. Proper diagnostic and therapeutical measures were undertaken to manage the disease immediately after stationary admission. Two weeks after an inconspicuous healing period, hemiparesis due to formation of an intracranial abscess developed. An emergent situation reveals which was unusual to the clinical situation. The possible role of underlying mechanisms of intracranial abscess formation is discussed and review of literature concerning orbital and intracranial rhinosinusitis complications is performed. The correct indication of imaging methods and accurate evaluation of diminutive symptoms are essential. We assume that performance of a complementary CT of the brain or MRI even when previous CT scan of the orbit/paranasal sinuses reveals no cerebral pathology should be done to avoid or minimize future patients with consecutive orbital and intracranial complications of acute rhinosinusitis.

  2. [Is it possible to identify dengue in children on the basis of Ministry of Health criteria for suspected dengue cases?].

    Science.gov (United States)

    Rodrigues, Marisa B P; Freire, Heliane B M; Corrêa, Paulo R L; Mendonça, Marislaine L; Silva, Maria Regina I; França, Elizabeth B

    2005-01-01

    To identify clinical characteristics indicative of dengue and to evaluate the applicability to children of the Health Ministry criteria for suspected cases. A cross-sectional study undertaken at the General Pediatrics Center of the Fundação Hospitalar de Minas Gerais. Children were enrolled if presenting acute febrile conditions with no definite etiology, lasting > 24 hours and disease. The subset of children who did have dengue was compared with the subset of nonspecific acute febrile diseases. The Health Ministry criteria for suspected cases was evaluated. Dengue was diagnosed in 50.4% of the 117 children studied. There were no statistically significant associations between the disease and the majority of the symptoms analyzed. Only exanthema was more often associated with dengue (Prevalence Ratio = 1.49; 95% CI: 1.05-2.11). The criteria for suspected cases of dengue had a sensitivity of just 50.8% and a positive predictive value of 62.5%. These values were greater among schoolchildren and during the period of greater disease incidence. Dengue is common among febrile diseases of childhood, with prevalence that varies according to the epidemiological situation. The clinical status of children with dengue was very similar to that of children with other nonspecific diseases. The Health Ministry criteria for suspected cases was shown to be of little use, particularly with smaller children and during periods of reduced incidence.

  3. Unusual Sclerosing Orbital Pseudotumor Infiltrating Orbits and Maxillofacial Regions

    Directory of Open Access Journals (Sweden)

    Huseyin Toprak

    2014-01-01

    Full Text Available Idiopathic orbital pseudotumor (IOP is a benign inflammatory condition of the orbit without identifiable local or systemic causes. Bilateral massive orbital involvement and extraorbital extension of the IOP is very rare. We present an unusual case of IOP with bilateral massive orbital infiltration extending into maxillofacial regions and discuss its distinctive magnetic resonance imaging (MRI features that help to exclude other entities during differential diagnoses.

  4. Catalogue of Cometary Orbits 1997. 12th edition.

    Science.gov (United States)

    Marsden, B. G.; Williams, G. V.

    Beginning with the tenth edition, the catalogues have utilized the new cometary designation system that took effect at the beginning of 1995. This system was adopted by the IAU in August 1994 in a resolution reproduced on Minor Planet Circ., Nos. 23803 - 23804. This edition contains 1582 orbits for 1548 cometary apparitions and is intended to be complete for comets observed up to September 1997. The presentation of the general tabulation of the orbits has been changed from that in earlier editions in two significant ways. Firstly, the basic orbital data are given on the left-hand pages, while the facing pages contain subsidiary information, notably the references to the original sources of the data. Secondly, the basic data are themselves separated into two parts, with the orbits for single-apparition and multiple-apparition comets listed separately. Contents: 1. Introduction. 2. General catalogue (long-period and unnumbered periodic comets, numbered periodic comets). 3. Identifications. 4. 1997 elements for numbered periodic comets. 5. 1998 - 1999 elements for numbered periodic comets. 6. Statistical tables (numbered periodic comets, unnumbered periodic comets, comets that may be of short period, parabolic and nearly-parabolic orbits in order of i). 7. Correspondence of new-style and old-style designations (by Roman numeral, by letter designation). 8. X/comets.

  5. Low Earth Orbit Satellite’s Orbit Propagation and Determination

    Science.gov (United States)

    2014-01-01

    Institute of Technology Email: honien.shou@xuite.net Abstract This paper represents orbit propagation and determination of Low Eearth Orbit(LEO...Arichandran, S. H. Tan, T. Bretschneider, High – Presicion Onboard Orbit Determination for Small Satellites - the GPS-Based XNS on X-SAT. 6th Symposium on

  6. Local orbitals by minimizing powers of the orbital variance

    DEFF Research Database (Denmark)

    Jansik, Branislav; Høst, Stinne; Kristensen, Kasper

    2011-01-01

    is obtained. For increasing power exponents, the penalty for delocalized orbitals is increased and smaller maximum orbital spreads are encountered. Calculations on superbenzene, C60, and a fragment of the titin protein show that for a power exponent equal to one, delocalized outlier orbitals may...

  7. PMS2 Involvement in Patients Suspected of Lynch Syndrome

    NARCIS (Netherlands)

    Niessen, Renee C.; Kleibeuker, Jan H.; Westers, Helga; Jager, Paul O. J.; Rozeveld, Dennie; Bos, Krista K.; Boersma-van Ek, Wytske; Hollema, Harry; Sijmons, Rolf H.; Hofstra, Robert M. W.

    It is well-established that germline mutations in the mismatch repair genes MLH1, MSH2, and MSH6 cause Lynch syndrome. However, mutations in these three genes do not account for all Lynch syndrome (suspected) families. Recently, it was shown that germline mutations in another mismatch repair gene,

  8. Faecal Calprotectin in Suspected Paediatric Inflammatory Bowel Disease

    NARCIS (Netherlands)

    Degraeuwe, Pieter L. J.; Beld, Monique P. A.; Ashorn, Merja; Canani, Roberto Berni; Day, Andrew S.; Diamanti, Antonella; Fagerberg, Ulrika L.; Henderson, Paul; Kolho, Kaija-Leena; Van de Vijver, Els; van Rheenen, Patrick F.; Wilson, David C.; Kessels, Alfons G. H.

    Objectives: The diagnostic accuracy of faecal calprotectin (FC) concentration for paediatric inflammatory bowel disease (IBD) is well described at the population level, but not at the individual level. We reassessed the diagnostic accuracy of FC in children with suspected IBD and developed an

  9. Stabilization of the spine in patients with suspected cervical spine ...

    African Journals Online (AJOL)

    Stabilization of the spine in patients with suspected cervical spine injury in Mulago Hospital. BM Ndeleva, T Beyeza. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/eaoj.v5i1.67487 · AJOL African Journals ...

  10. Talking heads : interviewing suspects from a cultural perspective

    NARCIS (Netherlands)

    Beune, K.

    2009-01-01

    Although the literature on the interviewing of suspects has increased over the past decade, research on the use and effectiveness of police strategies and their boundary conditions is very rare. The present dissertation aims to fill this void by identifying behaviors that appeal to and persuade

  11. Nonreferral of Nursing Home Patients With Suspected Breast Cancer

    NARCIS (Netherlands)

    Hamaker, Marije E.; Hamelinck, Victoria C.; van Munster, Barbara C.; Bastiaannet, Esther; Smorenburg, Carolien H.; Achterberg, Wilco P.; Liefers, Gerrit-Jan; de Rooij, Sophia E.

    2012-01-01

    Introduction: People with suspected breast cancer who are not referred for diagnostic testing remain unregistered and are not included in cancer statistics. Little is known about the extent of and motivation for nonreferral of these patients. Methods: A Web-based survey was sent to all elderly care

  12. DNA typing from vaginal smear slides in suspected rape cases

    Directory of Open Access Journals (Sweden)

    Dayse Aparecida da Silva

    Full Text Available In an investigation of suspected rape, proof of sexual assault with penetration is required. In view of this, detailed descriptions of the genitalia, the thighs and pubic region are made within the forensic medical service. In addition, vaginal swabs are taken from the rape victim and some of the biological material collected is then transferred to glass slides. In this report, we describe two rape cases solved using DNA typing from cells recovered from vaginal smear slides. In 1999, two young women informed the Rio de Janeiro Police Department that they had been victims of sexual assaults. A suspect was arrested and the victims identified him as the offender. The suspect maintained that he was innocent. In order to elucidate these crimes, vaginal smear slides were sent to the DNA Diagnostic Laboratory for DNA analysis three months after the crimes, as unique forensic evidence. To get enough epithelial and sperm cells to perform DNA analysis, we used protocols modified from the previously standard protocols used for DNA extraction from biological material fixed on glass slides. The quantity of cells was sufficient to perform human DNA typing using nine short tandem repeat (STR loci. It was 3.3 billion times more probable that it was the examined suspect who had left sperm cells in the victims, rather than any other individual in the population of Rio de Janeiro.

  13. Cognitive Linguistic Performances of Multilingual University Students Suspected of Dyslexia

    Science.gov (United States)

    Lindgren, Signe-Anita; Laine, Matti

    2011-01-01

    High-performing adults with compensated dyslexia pose particular challenges to dyslexia diagnostics. We compared the performance of 20 multilingual Finnish university students with suspected dyslexia with 20 age-matched and education-matched controls on an extensive test battery. The battery tapped various aspects of reading, writing, word…

  14. Differential Diagnosis of Children with Suspected Childhood Apraxia of Speech

    Science.gov (United States)

    Murray, Elizabeth; McCabe, Patricia; Heard, Robert; Ballard, Kirrie J.

    2015-01-01

    Purpose: The gold standard for diagnosing childhood apraxia of speech (CAS) is expert judgment of perceptual features. The aim of this study was to identify a set of objective measures that differentiate CAS from other speech disorders. Method: Seventy-two children (4-12 years of age) diagnosed with suspected CAS by community speech-language…

  15. A suspected case of Addison’s disease in cattle

    OpenAIRE

    Lambacher, Bianca; Wittek, Thomas

    2015-01-01

    A 4.75-year old Simmental cow was presented with symptoms of colic and ileus. The clinical signs and blood analysis resulted in the diagnosis of suspected primary hypoadrenocorticism (Addison’s disease). Although Addison’s disease has been frequently described in other domestic mammals, to our knowledge, this disease has not previously been reported in cattle.

  16. Is extended biopsy protocol justified in all patients with suspected ...

    African Journals Online (AJOL)

    Objective: To determine the significance of an extended 10-core transrectal biopsy protocol in different categories of patients with suspected prostate cancer using digital guidance. Materials and Methods: We studied 125 men who were being evaluated for prostate cancer. They all had an extended 10-core digitally guided ...

  17. Correlates and Suspected Causes of Obesity in Children

    Science.gov (United States)

    Crothers, Laura M.; Kehle, Thomas J.; Bray, Melissa A.; Theodore, Lea A.

    2009-01-01

    The correlates and suspected causes of the intractable condition obesity are complex and involve environmental and heritable, psychological and physical variables. Overall, the factors associated with and possible causes of it are not clearly understood. Although there exists some ambiguity in the research regarding the degree of happiness in…

  18. Medical Evaluation of Suspected Child Sexual Abuse: 2011 Update

    Science.gov (United States)

    Adams, Joyce A.

    2011-01-01

    The medical evaluation of children with suspected sexual abuse includes more than just the physical examination of the child. The importance of taking a detailed medical history from the parents and a history from the child about physical sensations following sexual contact has been emphasized in other articles in the medical literature. The…

  19. Selective screening in neonates suspected to have inborn errors of ...

    African Journals Online (AJOL)

    Background: Inborn errors of metabolism (IEM) have a high morbidity and mortality in neonates. Unfortunately, there is no nationwide neonatal screen in Egypt, so several cases may be missed. Objective: The aim of this work was to detect the prevalence of IEM among neonates with suspected IEM, and to diagnose IEM as ...

  20. Sexual Health Before Treatment in Women with Suspected Gynecologic Malignancy.

    Science.gov (United States)

    Bretschneider, C Emi; Doll, Kemi M; Bensen, Jeannette T; Gehrig, Paola A; Wu, Jennifer M; Geller, Elizabeth J

    2017-08-22

    Sexual health in survivors of gynecologic cancer has been studied; however, sexual health in these women before treatment has not been thoroughly evaluated. The objective of our study was to describe the pretreatment characteristics of sexual health of women with suspected gynecologic cancer before cancer treatment. We performed a cross-sectional analysis of women with a suspected gynecologic cancer, who were prospectively enrolled in a hospital-based cancer survivorship cohort from August 2012 to June 2013. Subjects completed the validated Patient-Reported Outcomes Measurement Information System Sexual Function and Satisfaction Questionnaire. Pretreatment sexual health was assessed in terms of sexual interest, desire, lubrication, discomfort, orgasm, enjoyment, and satisfaction. Of 186 eligible women with suspected gynecologic cancer, 154 (82%) completed the questionnaire pretreatment. Mean age was 58.1 ± 13.3 years. Sexual health was poor: 68.3% reported no sexual activity, and 54.7% had no interest in sexual activity. When comparing our study population to the general U.S. population, the mean pretreatment scores for the subdomains of lubrication and vaginal discomfort were similar, while sexual interest was significantly lower and global satisfaction was higher. In a linear regression model, controlling for cancer site, age remained significantly associated with sexual function while cancer site did not. Problems with sexual health are prevalent in women with suspected gynecologic malignancies before cancer treatment. Increasing awareness of the importance of sexual health in this population will improve quality of life for these women.

  1. Use of budesonide Turbuhaler in young children suspected of asthma

    DEFF Research Database (Denmark)

    Bisgaard, H; Pedersen, S; Nikander, K

    1994-01-01

    The question addressed in this study was the ability of young children to use a dry-powder inhaler, Turbuhaler. One hundred and sixty five children suspected of asthma, equally distributed in one year age-groups from 6 months to 8 yrs, inhaled from a Pulmicort Turbuhaler, 200 micrograms budesonid...

  2. Doppler ultrasound in the assessment of suspected intra-uterine ...

    African Journals Online (AJOL)

    Ramakantb

    obesity with hypertension and non-insulin-dependent diabetes mellitus.[3] In this review, a brief discussion about the ultrasound diagnosis of suspected IUGR, and thereafter about the use of Doppler ultrasound in the diagnosis of IUGR, will be ... before that, all fetuses have relatively larger heads, which will mask the brain-.

  3. Candida meningitis in a suspected immunosuppressive patient - A ...

    African Journals Online (AJOL)

    Candida meningitis in a suspected immunosuppressive patient - A case report. EO Sanya, NB Ameen, BA Onile. Abstract. No Abstract. West African Journal of Medicine Vol. 25 (1) 2006: pp.79-81. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  4. Ajmaline challenge in young individuals with suspected Brugada syndrome

    NARCIS (Netherlands)

    Sorgente, A.; Sarkozy, A.; Asmundis, C. de; Chierchia, G.B.; Capulzini, L.; Paparella, G.; Henkens, S.; Brugada, P.

    2011-01-01

    BACKGROUND: The clinical characteristics and the results of ajmaline challenge in young individuals with suspected Brugada syndrome (BS) have not been systematically investigated. METHODS: Among a larger series of patients included in the BS database of our Department, 179 patients undergoing

  5. A Diagnostic Program for Patients Suspected of Having Lung Cancer

    NARCIS (Netherlands)

    Stigt, Jos A.; Uil, Steven M.; Oostdijk, Ad H.; Boers, James E.; van den Berg, Jan-Willem K.; Groen, Harry J. M.

    2012-01-01

    In 297 patients suspected of having lung cancer, invasive diagnostic procedures followed positron emission tomography/computed tomography (PET-CT) on the same day. For patients with a diagnosis of malignancy (215/297), investigations were finalized on 1 day in 85%, and bronchoscopy was performed in

  6. Use of Chest Radiography In Patients Suspected of Pulmonary ...

    African Journals Online (AJOL)

    may be rushed into treatfng all cases of cough, fever and weight loss with negative sputums as PTB, and other diagnoses may be overlooked. A cheaper, quicker way of screening TB suspects would help con- siderably in this common problem. In Febuary 1991, the Norwegian Government do- nated two Odelka camer;l,s to ...

  7. Radial periodic perturbations of the Kepler problem

    Science.gov (United States)

    Fonda, Alessandro; Gallo, Anna Chiara

    2017-11-01

    We consider radial periodic perturbations of a central force field and prove the existence of rotating periodic solutions, whose orbits are nearly circular. The proof is mainly based on the Implicit Function Theorem, and it permits to handle some small perturbations involving the velocity, as well. Our results apply, in particular, to the classical Kepler problem.

  8. Opioid analgesic administration in patients with suspected drug use.

    Science.gov (United States)

    Kreling, Maria Clara Giorio Dutra; Mattos-Pimenta, Cibele Andrucioli de

    2017-01-01

    To identify the prevalence of patients suspected of drug use according to the nursing professionals' judgement, and compare the behavior of these professionals in opioid administration when there is or there is no suspicion that patient is a drug user. A cross-sectional study with 507 patients and 199 nursing professionals responsible for administering drugs to these patients. The Chi-Square test, Fisher's Exact and a significance level of 5% were used for the analyzes. The prevalence of suspected patients was 6.7%. The prevalence ratio of administration of opioid analgesics 'if necessary' is twice higher among patients suspected of drug use compared to patients not suspected of drug use (p = 0.037). The prevalence of patients suspected of drug use was similar to that of studies performed in emergency departments. Patients suspected of drug use receive more opioids than patients not suspected of drug use. Identificar a prevalência de pacientes com suspeita de uso de drogas conforme opinião de profissionais de enfermagem e comparar a conduta desses profissionais na administração de opioides quando há ou não suspeita de que o paciente seja usuário de drogas. Estudo transversal com 507 pacientes e 199 profissionais de enfermagem responsáveis pela administração de medicamentos a esses pacientes. Para as análises foram utilizados os testes de Qui-Quadrado, Exato de Fisher e um nível de significância de 5%. A prevalência de pacientes suspeitos foi 6,7%. A razão de prevalência de administração de analgésicos opioides "se necessário" é duas vezes maior entre os pacientes suspeitos em relação aos não suspeitos (p=0,037). A prevalência de suspeitos foi semelhante à de estudos realizados em departamentos de emergência. Os suspeitos de serem usuários de drogas recebem mais opioides do que os não suspeitos.

  9. Dynamics of Orbits near 3:1 Resonance in the Earth-Moon System

    Science.gov (United States)

    Dichmann, Donald J.; Lebois, Ryan; Carrico, John P., Jr.

    2013-01-01

    The Interstellar Boundary Explorer (IBEX) spacecraft is currently in a highly elliptical orbit around Earth with a period near 3:1 resonance with the Moon. Its orbit is oriented so that apogee does not approach the Moon. Simulations show this orbit to be remarkably stable over the next twenty years. This article examines the dynamics of such orbits in the Circular Restricted 3-Body Problem (CR3BP). We look at three types of periodic orbits, each exhibiting a type of symmetry of the CR3BP. For each of the orbit types, we assess the local stability using Floquet analysis. Although not all of the periodic solutions are stable in the mathematical sense, any divergence is so slow as to produce practical stability over several decades. We use Poincare maps with twenty-year propagations to assess the nonlinear stability of the orbits, where the perturbation magnitudes are related to the orbit uncertainty for the IBEX mission. Finally we show that these orbits belong to a family of orbits connected in a bifurcation diagram that exhibits exchange of stability. The analysis of these families of period orbits provides a valuable starting point for a mission orbit trade study.

  10. Plotting Orbital Trajectories For Maneuvers

    Science.gov (United States)

    Brody, Adam R.

    1991-01-01

    Interactive Orbital Trajectory Planning Tool (EIVAN) computer program is forward-looking interactive orbit-trajectory-plotting software tool for use with proximity operations (operations occurring within 1-km sphere of space station) and other maneuvers. Developed to plot resulting trajectories, to provide better comprehension of effects of orbital mechanics, and to help user develop heuristics for planning missions on orbit. Program runs with Microsoft's Excel for execution on MacIntosh computer running MacIntosh OS.

  11. Preseptal and orbital cellulitis

    Directory of Open Access Journals (Sweden)

    Emine Akçay

    2014-09-01

    Full Text Available Preseptal cellulitis (PC is defined as an inflammation of the eyelid and surrounding skin, whereas orbital cellulitis (OC is an inflammation of the posterior septum of the eyelid affecting the orbit and its contents. Periorbital tissues may become infected as a result of trauma (including insect bites or primary bacteremia. Orbital cellulitis generally occurs as a complication of sinusitis. The most commonly isolated organisms are Staphylococcus aureus, Streptococcus pneumoniae, S. epidermidis, Haempphilus influenzae, Moraxella catarrhalis and S. pyogenes. The method for the diagnosis of OS and PS is computed tomography. Using effective antibiotics is a mainstay for the treatment of PC and OC. There is an agreement that surgical drainage should be performed in cases of complete ophthalmoplegia or significant visual impairment or large abscesses formation. This infections are also at a greater risk of acute visual loss, cavernous sinus thrombosis, meningitis, cerebritis, endophthalmitis, and brain abscess in children. Early diagnosis and appropriate treatment are crucial to control the infection. Diagnosis, treatment, management and complications of PC and OC are summarized in this manuscript. J MicrobiolInfect Dis 2014; 4(3: 123-127

  12. V/P SPECT as a diagnostic tool for pregnant women with suspected pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Bajc, Marika; Olsson, Berit; Joegi, Jonas [Skaane University Hospital and Lund University, Clinical Physiology and Nuclear Medicine, Lund (Sweden); Gottsaeter, Anders [Skaane University Hospital, Vascular Diseases, Malmoe (Sweden); Hindorf, Cecilia [Skaane University Hospital, Radiation Physics, Lund (Sweden)

    2015-07-15

    The purpose of the study was to assess the prevalence of pulmonary embolism (PE) and other lung diseases among pregnant women with suspected PE and to calculate the radiation exposure to patient and fetus in this population. As a secondary aim, we evaluated the negative predictive value of a normal ventilation/perfusion single photon emission computed tomography (V/P SPECT) examination in pregnancy. We studied all 127 pregnant women who had suspected PE and had undergone V/P SPECT at our institution in the course of a 5-year period. Radiation exposure to patient and fetus and the negative predictive value of a normal V/P SPECT examination were also measured. V/P SPECT identified PE in 11 women (9 %). Moreover, in 15 women (12 %) the examination revealed pneumonia (in 2 cases in addition to PE) and in 1 woman signs of airway obstruction were revealed. Among the 116/127 women (91 %) where PE was ruled out by V/P SPECT, none was diagnosed subsequently with PE or deep venous thrombosis (DVT) during the same pregnancy or puerperal period. For P SPECT, the calculated fetal absorbed dose was < 0.6 mGy,and the calculated breast absorbed dose 0.6 mGy. For V SPECT, the calculated fetal absorbed dose was < 0.014 mGy and the breast absorbed dose 0.25 mGy. The prevalence of PE was low (9 %) among pregnant women with suspected disease. Pneumonia was diagnosed in 12 % of patients. The negative predictive value of V/P SPECT was high, and the radiation exposure from V/P SPECT was low both for fetus and patient. (orig.)

  13. Orbits of four double stars

    Directory of Open Access Journals (Sweden)

    Novaković B.

    2006-01-01

    Full Text Available We present orbits of four double stars. Orbits of stars WDS 23516+4205 = ADS 17050 and WDS 18239+5848 = ADS 11336 were calculated for the first time. Orbits of double stars WDS 02022+3643 = ADS 1613 and WDS 18443+3940 = ADS 11635 were revised. We have also determined their masses, dynamical parallaxes and ephemerides.

  14. Orbital Cellulitis of Odontogenic Origin.

    Science.gov (United States)

    Yan, William; Chakrabarti, Rahul; Choong, Jessica; Hardy, Thomas

    2015-01-01

    Odontogenic orbital cellulitis, although uncommon, has the potential to cause severe vision loss if unsuspected and untreated. Compared to non-odontogenic bacteriology, odontogenic orbital abscesses typically feature a heavy mixed growth with anaerobic organisms. We review the literature and discuss the case of a 26-year-old male who presented with anaerobic orbital cellulitis for treatment.

  15. Retinoblastoma associated orbital cellulitis

    Science.gov (United States)

    Mullaney, P.; Karcioglu, Z.; Huaman, A.; Al-Mesfer, S.

    1998-01-01

    AIM—Preseptal and orbital cellulitis are rare presenting features of intraocular retinoblastoma. The objectives of this study were to determine the frequency of retinoblastoma associated cellulitis, as well as to review its clinical and histopathological features.
METHODS—The medical records of 292 retinoblastoma patients in the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia were reviewed. Those indicating a history of, or presenting with, cellulitis were retrieved and their clinical, radiological, and histopathological variables were assessed. Patients with definite extraocular tumour extension on clinical or radiological examination were excluded.
RESULTS—14 patients were found to have retinoblastoma associated cellulitis (4.8%); nine had bilateral and five had unilateral retinoblastoma. Conjunctival and blood cultures were performed in 10 cases and were negative. 10 children were treated with intravenous steroids, often in conjunction with antibiotics, resulting in a prompt decrease in inflammation. Three other children were treated with antibiotics alone and one received no treatment. Computed tomographic scanning depicted large intraocular tumours occupying between 80% and 100% of the globe in each case. In eight patients, periocular inflammation was radiologically interpreted as possible extraocular extension. In one patient serial computed tomographic scanning showed a reduction in intraocular calcification over time which occurred in the presence of cellulitis. 12 patients underwent enucleation and histopathological examination revealed large necrotic, poorly differentiated tumours associated with uveal involvement and early optic nerve invasion. Focal perilimbal destruction was seen in one patient, and in another peripapillary extrascleral extension was present. 12 patients are alive with a mean follow up of 56.4 months.
CONCLUSIONS—Radiological evaluation of scleral integrity may be hindered by periocular inflammatory

  16. THE SPECTROSCOPIC ORBITS OF FIVE γ DORADUS STARS

    Energy Technology Data Exchange (ETDEWEB)

    Fekel, Francis C.; Henry, Gregory W. [Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Boulevard, Box 9501, Nashville, TN 37209 (United States); Pourbaix, Dimitri, E-mail: fekel@evans.tsuniv.edu, E-mail: gregory.w.henry@gmail.com, E-mail: pourbaix@astro.ulb.ac.be [FNRS Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles, CP 226, B-1050 Bruxelles (Belgium)

    2016-02-15

    We have determined the spectroscopic orbits of five γ Dor variables, HD 776, HD 6568, HD 17310, HD 19684, and HD 62196. Their orbital periods range from 27.8 to 1163 days and their eccentricities from 0.01 to 0.65. Of the five systems, only HD 19684 shows lines of its binary companion, but those lines are always so weak and blended with the lines of the primary that we were unable to measure them satisfactorily. The velocity residuals of the orbital fits were searched for periodicities associated with pulsation. No clear, convincing case for velocity periodicities in the residuals was found in four of the five stars. However, for HD 17310 we identified a period of 2.13434 days, a value in agreement with the largest amplitude period previously found photometrically for that star. The velocity residuals of HD 62196 have a long-term trend suggesting that it is a triple system.

  17. Effects of solar radiation on the orbits of small particles

    Science.gov (United States)

    Lyttleton, R. A.

    1976-01-01

    A modification of the Robertson (1937) equations of particle motion in the presence of solar radiation is developed which allows for partial reflection of sunlight as a result of rapid and varying particle rotations caused by interaction with the solar wind. The coefficients and forces in earlier forms of the equations are compared with those in the present equations, and secular rates of change of particle orbital elements are determined. Orbital dimensions are calculated in terms of time, probable sizes and densities of meteoric and cometary particles are estimated, and times of infall to the sun are computed for a particle moving in an almost circular orbit and a particle moving in an elliptical orbit of high eccentricity. Changes in orbital elements are also determined for particles from a long-period sun-grazing comet. The results show that the time of infall to the sun from a highly eccentric orbit is substantially shorter than from a circular orbit with a radius equal to the mean distance in the eccentric orbit. The possibility is considered that the free orbital kinetic energy of particles drawn into the sun may be the energy source for the solar corona.

  18. Numerical simulation of orbiting black holes.

    Science.gov (United States)

    Brügmann, Bernd; Tichy, Wolfgang; Jansen, Nina

    2004-05-28

    We present numerical simulations of binary black hole systems which for the first time last for about one orbital period for close but still separate black holes as indicated by the absence of a common apparent horizon. An important part of the method is the construction of comoving coordinates, in which both the angular and the radial motion are minimized through a dynamically adjusted shift condition. We use fixed mesh refinement for computational efficiency.

  19. Depressed mood, positive affect, and heart rate variability in patients with suspected coronary artery disease.

    Science.gov (United States)

    Bhattacharyya, Mimi R; Whitehead, Daisy L; Rakhit, Roby; Steptoe, Andrew

    2008-11-01

    To test associations between heart rate variability (HRV), depressed mood, and positive affect in patients with suspected coronary artery disease (CAD). Depression is associated with impaired HRV post acute cardiac events, but evidence in patients with stable coronary artery disease (CAD) is inconsistent. Seventy-six patients (52 men, 24 women; mean age = 61.1 years) being investigated for suspected CAD on the basis of symptomatology and positive noninvasive tests, completed 24-hour electrocardiograms. The Beck Depression Inventory (BDI) was administered, and positive and depressed affect was measured over the study period with the Day Reconstruction Method (DRM). A total of 46 (60.5%) patients were later found to have definite CAD. HRV was analyzed, using spectral analysis. Typical diurnal profiles of HRV were observed, with greater normalized high frequency (HF) and lower normalized low frequency (LF) power in the night compared with the day. BDI depression scores were not consistently associated with HRV. But positive affect was associated with greater normalized HF power (p = .039) and reduced normalized LF power (p = .007) independently of age, gender, medication with beta blockers, CAD status, body mass index, smoking, and habitual physical activity level. In patients with definite CAD, depressed affect assessed using the DRM was associated with reduced normalized HF power and heightened normalized LF power (p = .007) independently of covariates. Relationships between depression and HRV in patients with CAD may depend on affective experience over the monitoring period. Enhanced parasympathetic cardiac control may be a process through which positive affect protects against cardiovascular disease.

  20. Orbital maneuvers and space rendezvous

    Science.gov (United States)

    Butikov, Eugene I.

    2015-12-01

    Several possibilities of launching a space vehicle from the orbital station are considered and compared. Orbital maneuvers discussed in the paper can be useful in designing a trajectory for a specific space mission. The relative motion of orbiting bodies is investigated on examples of spacecraft rendezvous with the space station that stays in a circular orbit around the Earth. An elementary approach is illustrated by an accompanying simulation computer program and supported by a mathematical treatment based on fundamental laws of physics and conservation laws. Material is appropriate for engineers and other personnel involved in space exploration, undergraduate and graduate students studying classical physics and orbital mechanics.

  1. Gravitational waves from periodic three-body systems.

    Science.gov (United States)

    Dmitrašinović, V; Suvakov, Milovan; Hudomal, Ana

    2014-09-05

    Three bodies moving in a periodic orbit under the influence of Newtonian gravity ought to emit gravitational waves. We have calculated the gravitational radiation quadrupolar waveforms and the corresponding luminosities for the 13+11 recently discovered three-body periodic orbits in Newtonian gravity. These waves clearly allow one to distinguish between their sources: all 13+11 orbits have different waveforms and their luminosities (evaluated at the same orbit energy and body mass) vary by up to 13 orders of magnitude in the mean, and up to 20 orders of magnitude for the peak values.

  2. Orbital Debris: A Policy Perspective

    Science.gov (United States)

    Johnson, Nicholas L.

    2007-01-01

    A viewgraph presentation describing orbital debris from a policy perspective is shown. The contents include: 1) Voyage through near-Earth Space-animation; 2) What is Orbital Debris?; 3) Orbital Debris Detectors and Damage Potential; 4) Hubble Space Telescope; 5) Mir Space Station Solar Array; 6) International Space Station; 7) Space Shuttle; 8) Satellite Explosions; 9) Satellite Collisions; 10) NASA Orbital Debris Mitigation Guidelines; 11) International Space Station Jettison Policy; 12) Controlled/Uncontrolled Satellite Reentries; 13) Return of Space Objects; 14) Orbital Debris and U.S. National Space Policy; 15) U.S Government Policy Strategy; 16) Bankruptcy of the Iridium Satellite System; 17) Inter-Agency Space Debris Coordination Committee (IADC); 18) Orbital Debris at the United Nations; 19) Chinese Anti-satellite System; 20) Future Evolution of Satellite Population; and 21) Challenge of Orbital Debris

  3. Mars Observer Orbit Insertion Briefing

    Science.gov (United States)

    1993-01-01

    Steve Wall is the host of this video entitled, "Return to the Red Planet". Live animation of the Mars Observer orbiting Mars is presented. Steve Wall explains the spacecraft insertion maneuver and also explains the purpose for the Mars Observer launch. Live coverage of the Cape Canaveral launch of the Mars Observer is also presented. Suzanne Dodd, Chief of the Mission Planning team describes the burn start and how the spacecraft will be captured by Mars' gravity. Glenn Cunningham, Mars Observer Project Manager, gives background information on the Mars Observer and describes the organizations behind the Mars Observer Spacecraft, such as the Deep Space Network, the Mission Operation Support Office, Science Investigators, the Flight Engineering Office, Operations Office, and the Ground Data System Office. Dr. William Piotrowski, Acting Director, Solar System Exploration Division, NASA, talks about the purpose of the Mars Pathfinder which is to develop the technology and systems for landing small science packages on Mars. Mr. Roger Gibbs, Former Mars Observer Spacecraft Systems Engineer, tells us how the Mars Observer was built and describes the structural elements on the Mars Observer. The 11-month cruise period for the spacecraft is given by Joseph Beerer, Manager of the Engineering office. The thrust for the Mars Orbit Insertion is described by Ronald Klemetson, Technical Manager, Propulsion Subsystem Jet Propulsion Laboratory (JPL). George Chen, Lead Engineer Attitude and Articulation Subsystem Spacecraft Team, explains the importance of the attitude control engines on the Spacecraft. Marvin Traxler, Manager of Tracking and Data Acquisition, describes how searching for a signal from the Mars Observer works. See NONP-NASA-VT-2000081555 for a continuation of this discussion with Marvin Traxler.

  4. Orbit Propagation and Determination of Low Earth Orbit Satellites

    Directory of Open Access Journals (Sweden)

    Ho-Nien Shou

    2014-01-01

    Full Text Available This paper represents orbit propagation and determination of low Earth orbit (LEO satellites. Satellite global positioning system (GPS configured receiver provides position and velocity measures by navigating filter to get the coordinates of the orbit propagation (OP. The main contradictions in real-time orbit which is determined by the problem are orbit positioning accuracy and the amount of calculating two indicators. This paper is dedicated to solving the problem of tradeoffs. To plan to use a nonlinear filtering method for immediate orbit tasks requires more precise satellite orbit state parameters in a short time. Although the traditional extended Kalman filter (EKF method is widely used, its linear approximation of the drawbacks in dealing with nonlinear problems was especially evident, without compromising Kalman filter (unscented Kalman Filter, UKF. As a new nonlinear estimation method, it is measured at the estimated measurements on more and more applications. This paper will be the first study on UKF microsatellites in LEO orbit in real time, trying to explore the real-time precision orbit determination techniques. Through the preliminary simulation results, they show that, based on orbit mission requirements and conditions using UKF, they can satisfy the positioning accuracy and compute two indicators.

  5. A rational clinical approach to suspected insulin allergy

    DEFF Research Database (Denmark)

    Bødtger, Uffe; Wittrup, M

    2005-01-01

    AIMS: Allergy to recombinant human (rDNA) insulin preparations is a rare complication of insulin therapy. However, insulin preparations contain several allergens, and several disorders can resemble insulin allergy. Studies evaluating the diagnostic procedures on suspected insulin allergy...... technique (n = 5), skin disease (n = 3) and other systemic allergy (n = 1). Nine other patients were found to be allergic to protamine (n = 3) or rDNA insulin (n = 6), and specific treatment was associated with relief in 8 patients (89%). Four patients had local reactions of unknown causes but symptom...... relief was obtained in three cases by unspecific therapy. Overall, 20 (91%) reported relief of symptoms. CONCLUSION: Our standardized investigative procedure of suspected insulin preparation (IP) allergy was associated with relief of symptoms in > 90% of patients. IP allergy was diagnosed in 41...

  6. Interdisciplinary action of nurses to children with suspected sexual abuse

    Directory of Open Access Journals (Sweden)

    Lia Leão Ciuffo

    2014-04-01

    Full Text Available Objective. Understanding the role of nurses as members of interdisciplinary teams in the care of children with suspected sexual abuse. Methodology. This is a qualitative research based on the sociological phenomenology of Alfred Schutz. In 2008 were interviewed eleven nurses who worked in reference institutions for the care of child victims of sexual abuse in Rio de Janeiro. Results. The category called 'Interacting with other professionals in child care' emerged from the analysis of performance of professionals. The intersubjective relations between the nurses and the interdisciplinary team will enable to understand the intent of care from the perspective of social, emotional and psychological needs of children and their families. Conclusion. Interdisciplinarity favored the development of actions based on acceptance, listening and agreements on possible solutions in the care of children with suspected sexual abuse.

  7. Atlantoaxial subluxation and nasopharyngeal necrosis complicating suspected granulomatosis with polyangiitis.

    Science.gov (United States)

    Mohapatra, Anand; Holekamp, Terrence F; Diaz, Jason A; Zebala, Lukas; Brasington, Richard

    2015-04-01

    Granulomatosis polyangiitis (GPA, formerly Wegener granulomatosis) is a vasculitis that typically involves the upper respiratory tract, lungs, and kidneys. The 2 established methods to confirm a suspicion of GPA are the antineutrophil cytoplasmic antibody (ANCA) test and biopsy. However, ANCA-negative cases have been known to occur, and it can be difficult to find biopsy evidence of granulomatous disease.We report a case of suspected granulomatosis with polyangiitis limited to the nasopharynx. With a negative ANCA and no histological evidence, our diagnosis was founded on the exclusion of other diagnoses and the response to cyclophosphamide therapy. This case is unique because the patient's lesion resulted in atlantoaxial instability, which required a posterior spinal fusion at C1-C2. This is the first reported case of suspected GPA producing damage to the cervical spine and threatening the spinal cord.

  8. Suspected side effects to the quadrivalent human papilloma vaccine

    DEFF Research Database (Denmark)

    Brinth, Louise; Theibel, Ann Cathrine; Pors, Kirsten

    2015-01-01

    INTRODUCTION: The quadrivalent vaccine that protects against human papilloma virus types 6, 11, 16 and 18 (Q-HPV vaccine, Gardasil) was included into the Danish childhood vaccination programme in 2009. During the past years, a collection of symptoms primarily consistent with sympathetic nervous...... system dysfunction have been described as suspected side effects to the Q-HPV vaccine. METHODS: We present a description of suspected side effects to the Q-HPV vaccine in 53 patients referred to our Syncope Unit for tilt table test and evaluation of autonomic nervous system function. RESULTS: All...... consistency in the reported symptoms as well as between our findings and those described by others. Our findings neither confirm nor dismiss a causal link to the Q-HPV vaccine, but they suggest that further research is urgently warranted to clarify the pathophysiology behind the symptoms experienced...

  9. Radiological (scintigraphic) evaluation of patients with suspected pulmonar thromboembolism

    Energy Technology Data Exchange (ETDEWEB)

    Biello, D.R.

    1987-06-19

    The optimal strategy for diagnostic evaluation of patients with suspected pulmonary thromboembolism (PE) is subject of controversial and often conflicting opinions. If untreated, as many as 30% of patients with PE may die. Conversely, anticoagulant therapy significantly decreases mortality from PE, but bleeding complications occur. Underdiagnosis may result in a preventable death, and overdiagnosis may lead to significant hemorrhage from unnecessary anticoagulant therapy. This article outlines a practical guide for the use of pulmonary ventilation-perfusion (V-P) scintigraphy in patients with suspected PE. Perfusion imaging involves the intravenous injection of radiolabeled particles ranging from 10 to 60 ..mu..m in diameter (technetium Tc 99m macroaggregated albumin or technetium Tc 99m serum albumin microspheres); these particles are trapped in the capillaries and precapillary arterioles of the lung. The radiolabeled particles are distributed to the lungs in proportion to regional pulmonary blood flow. The correspondence of perfusion defects to bronchopulmonary segments is best appreciated in the posterior oblique views.

  10. Resonant Orbital Dynamics in LEO Region: Space Debris in Focus

    Directory of Open Access Journals (Sweden)

    J. C. Sampaio

    2014-01-01

    Full Text Available The increasing number of objects orbiting the earth justifies the great attention and interest in the observation, spacecraft protection, and collision avoidance. These studies involve different disturbances and resonances in the orbital motions of these objects distributed by the distinct altitudes. In this work, objects in resonant orbital motions are studied in low earth orbits. Using the two-line elements (TLE of the NORAD, resonant angles and resonant periods associated with real motions are described, providing more accurate information to develop an analytical model that describes a certain resonance. The time behaviors of the semimajor axis, eccentricity, and inclination of some space debris are studied. Possible irregular motions are observed by the frequency analysis and by the presence of different resonant angles describing the orbital dynamics of these objects.

  11. Radiotherapy in three suspect cases of feline thymoma.

    Science.gov (United States)

    Kaser-Hotz, B; Rohrer, C R; Fidel, J L; Nett, C S; Hörauf, A; Hauser, B

    2001-01-01

    Radiation therapy for three cases of suspect feline thymoma is described. The thymoma was controlled for 4 years in case no. 1. Case no. 2 responded well to radiation therapy but was euthanized after 2 months because of a nasal adenocarcinoma. Case no. 3 continues to do well more than 8 months after radiotherapy. Difficulties in diagnosing feline thymomas are discussed, and biological behavior as well as different treatment modalities of feline and human thymomas are compared.

  12. Percutaneous cholecystocentesis in cats with suspected hepatobiliary disease.

    Science.gov (United States)

    Byfield, Victoria L; Callahan Clark, Julie E; Turek, Bradley J; Bradley, Charles W; Rondeau, Mark P

    2017-12-01

    Objectives The objective was to evaluate the safety and diagnostic utility of percutaneous ultrasound-guided cholecystocentesis (PUC) in cats with suspected hepatobiliary disease. Methods Medical records of 83 cats with suspected hepatobiliary disease that underwent PUC were retrospectively reviewed. Results At the time of PUC, at least one additional procedure was performed in 79/83 cats, including hepatic aspiration and/or biopsy (n = 75) and splenic aspiration (n = 18). Complications were noted in 14/83 cases, including increased abdominal fluid (n = 11), needle-tip occlusion (n = 1), failed first attempt to penetrate the gall bladder wall (n = 1) and pneumoperitoneum (n = 1). There were no reports of gall bladder rupture, bile peritonitis or hypotension necessitating treatment with vasopressor medication. Blood products were administered to 7/83 (8%) cats. Seventy-two cats (87%) survived to discharge. Of the cats that were euthanized (9/83) or died (2/83), none were reported as a definitive consequence of PUC. Bacteria were identified cytologically in 10/71 samples (14%); all 10 had a positive aerobic bacterial culture. Bile culture was positive in 11/80 samples (14%). Of the cases with a positive bile culture, cytological description of bacteria corresponded to the organism cultured in fewer than 50% of cases. The most common cytologic diagnosis was hepatic lipidosis (49/66). The most common histopathologic diagnosis was cholangitis (10/21). Conclusions and relevance PUC was safe in this group of cats with suspected hepatobiliary disease. Complications were likely associated with ancillary procedures performed at the time of PUC. Bile analysis yielded an abnormal result in nearly one-third of cats with suspected hepatobiliary disease. Complete agreement between bile cytology and culture was lacking. Further evaluation of the correlation between bile cytology and bile culture is warranted.

  13. Interviewing strategically to elicit admissions from guilty suspects

    OpenAIRE

    Tekin, Serra; Granhag, Pär Anders; Strömwall, Leif; Giolla, Erik Mac; Vrij, Aldert; Hartwig, Maria

    2015-01-01

    In this article we introduce a novel interviewing tactic to elicit admissions from guilty suspects. By influencing the suspects’ perception of the amount of evidence the interviewer holds against them, we aimed to shift the suspects’ counterinterrogation strategies from less to more forthcoming. The proposed tactic (SUE-Confrontation) is a development of the Strategic Use of Evidence (SUE) framework and aims to affect the suspects’ perception by confronting them with statement-evidence incons...

  14. MRI for clinically suspected pediatric appendicitis: case interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Michael M.; Brian, James M.; Methratta, Sosamma T.; Hulse, Michael A.; Choudhary, Arabinda K.; Eggli, Kathleen D.; Boal, Danielle K.B. [Penn State Milton S. Hershey Medical Center, Division of Pediatric Radiology, Department of Radiology, Hershey, PA (United States)

    2014-05-15

    As utilization of MRI for clinically suspected pediatric appendicitis becomes more common, there will be increased focus on case interpretation. The purpose of this pictorial essay is to share our institution's case interpretation experience. MRI findings of appendicitis include appendicoliths, tip appendicitis, intraluminal fluid-debris level, pitfalls of size measurements, and complications including abscesses. The normal appendix and inguinal appendix are also discussed. (orig.)

  15. MRI for clinically suspected pediatric appendicitis: an implemented program

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Michael M.; Gustas, Cristy N.; Choudhary, Arabinda K.; Methratta, Sosamma T.; Hulse, Michael A.; Eggli, Kathleen D.; Boal, Danielle K.B. [Penn State Milton S. Hershey Medical Center, Department of Radiology, Mail Code H066, 500 University Drive, P.O. Box 850, Hershey, PA (United States); Geeting, Glenn [Penn State Milton S. Hershey Medical Center, Department of Emergency Medicine, Hershey, PA (United States)

    2012-09-15

    Emergent MRI is now a viable alternative to CT for evaluating appendicitis while avoiding the detrimental effects of ionizing radiation. However, primary employment of MRI in the setting of clinically suspected pediatric appendicitis has remained significantly underutilized. To describe our institution's development and the results of a fully implemented clinical program using MRI as the primary imaging evaluation for children with suspected appendicitis. A four-sequence MRI protocol consisting of coronal and axial single-shot turbo spin-echo (SS-TSE) T2, coronal spectral adiabatic inversion recovery (SPAIR), and axial SS-TSE T2 with fat saturation was performed on 208 children, ages 3 to 17 years, with clinically suspected appendicitis. No intravenous or oral contrast material was administered. No sedation was administered. Data collection includes two separate areas: time parameter analysis and MRI diagnostic results. Diagnostic accuracy of MRI for pediatric appendicitis indicated a sensitivity of 97.6% (CI: 87.1-99.9%), specificity 97.0% (CI: 93.2-99.0%), positive predictive value 88.9% (CI: 76.0-96.3%), and negative predictive value 99.4% (CI: 96.6-99.9%). Time parameter analysis indicated clinical feasibility, with time requested to first sequence obtained mean of 78.7 +/- 52.5 min, median 65 min; first-to-last sequence time stamp mean 14.2 +/- 8.8 min, median 12 min; last sequence to report mean 57.4 +/- 35.2 min, median 46 min. Mean age was 11.2 +/- 3.6 years old. Girls represented 57% of patients. MRI is an effective and efficient method of imaging children with clinically suspected appendicitis. Using an expedited four-sequence protocol, sensitivity and specificity are comparable to CT while avoiding the detrimental effects of ionizing radiation. (orig.)

  16. Suspected spinocellular carcinoma of the inferior eyelid resulted multiple chalazion.

    Science.gov (United States)

    Onesti, Maria Giuseppina; Troccola, Antonietta; Maruccia, Michele; Conversi, Andrea; Scuderi, Gianluca

    2013-01-01

    Chalazion is a subacute granulomatous inflammation of the eyelid caused by retention of tarsal gland secretions and it's the most common inflammatory lesion of the eyelid. In cases of doubtful clinical presentation the diagnosis with a biopsy and a histopathological examination is important because it can orientate an appropriate surgical treatment. We report a case of a 64-years-old diabetic man, suspected for a spinocellular lesion of the inferior eyelid of the left eye, it resulted unexpectedly a chalazion.

  17. CT-guided biopsy of suspected malignancy: A potential pitfall

    Directory of Open Access Journals (Sweden)

    Steven Henderson

    2013-11-01

    Full Text Available Paragangliomas are rare catecholamine-secreting neuro-endocrine tumours that can arise from sympathetic or parasympathetic tissue. Any manipulation of these tumours, without appropriate medical therapy, can result in excess catecholamine release leading to a catecholamine crisis. Neuro-endocrine tumours must be considered prior to interventional biopsy of an unknown soft-tissue mass, and appropriate biochemical investigations should be performed in suspected cases to prevent catastrophic complications.

  18. [Three cases of suspected re-infection of mumps virus].

    Science.gov (United States)

    Hatanaka, Akio; Kamada, Tomoko; Honda, Keiji; Tazaki, Akihisa; Kishine, Naomi; Kawashima, Yoshiyuki

    2012-08-01

    A 32-year-old woman, 5-year-old girl, and 33-year-old man visited our otorhinolaryngology outpatient clinic with tumentia of the unilateral parotid gland. A high titer of serum IgG antibodies against the mumps virus was detected. Around the same time, other members of their families had the same parotid tumentia, and they were diagnosed as having their first mumps infection. Therefore, the diagnosis of the three cases was strongly suspected to be re-infection with mumps. In Japan, it was classically believed that the mumps virus infection occurs only once in patients and reinfection doesn't occur. However, some pediatricians in Japan have reported that re-infection with mumps is strongly suspected when high titers of serum IgG antibodies against the mumps virus are found at the initial visit. It is now believed many more examples of mumps re-infection cases have existed than we previously believed. When high titers of serum IgG antibodies against the mumps virus are detected at an initial visit in patients who have had mumps previously, re-infection should be strongly suspected. And to make it certain, we suggest that the mumps IgG antibodies should be checked twice to confirm the diagnosis. If elevation of the IgG antibodies persist, the diagnosis will be much more certain.

  19. MR delayed enhancement imaging findings in suspected acute myocarditis

    Energy Technology Data Exchange (ETDEWEB)

    Gahide, Gerald [CHU de Montpellier, Radiologie centrale - Pole Cardiovasculaire et Thoracique, Montpellier (France); Centre Hospitalo-Universitaire de Montpellier, Hopital A de Villeneuve, Montpellier (France); Bertrand, D.; Dacher, J.N. [CHU de Rouen, Radiologie centrale - Hopital Charles Nicolle, Rouen (France); Roubille, F.; Skaik, S.; Piot, C.; Leclerq, F. [CHU de Montpellier, Departement de Cardiologie - Pole Cardiovasculaire et Thoracique, Montpellier (France); Tron, C.; Cribier, A. [CHU de Rouen, Departement de Cardiologie - Hopital Charles Nicolle, Rouen (France); Vernhet, H. [CHU de Montpellier, Radiologie centrale - Pole Cardiovasculaire et Thoracique, Montpellier (France)

    2010-01-15

    The purpose of the study was to prospectively assess the clinical impact of routinely performed delayed enhancement imaging in suspected acute myocarditis. A two-centre prospective study was performed in patients with suspected acute myocarditis. The protocol included horizontal long axis, vertical long axis and short axis cine MR and delayed enhancement imaging after Gd-DTPA infusion (0.2 mmol/kg). Sixty consecutive patients were enrolled (aged 49.4{+-}17.8 years). MRI demonstrated delayed enhancement sparing the subendocardicardial layer in 51.6% of patients, concordant with the diagnosis of acute myocarditis; 16.7% of patients exhibited delayed enhancement involving the subendocardial layer with irregular margins, concordant with the diagnosis of acute myocardial infarction; 31.7% of patients had delayed enhancement imaging that was considered normal. Routine imaging to identify delayed enhancement provided crucial information in suspected acute myocarditis by reinforcing the diagnosis in 51.6% of patients and correcting a misdiagnosed acute myocardial infarction in 16.7% of patients. (orig.)

  20. Low dose computed tomography in suspected acute renal colic.

    Science.gov (United States)

    Meagher, T; Sukumar, V P; Collingwood, J; Crawley, T; Schofield, D; Henson, J; Lakin, K; Connolly, D; Giles, J

    2001-11-01

    To evaluate whether computed tomography (CT) of the renal tract in suspected renal colic using reduced exposure factors maintains diagnostic accuracy. Prospective multi-centre cohort study. Patients with suspected renal colic were examined using computed tomography (CT) of the renal tract followed by intravenous urography (IVU) in four different centres with five different CT systems. Sixty-nine patients with suspected renal colic had CT of the renal tract followed by IVU. CT was performed with reduced exposure factors, giving a mean CT effective dose of 3.5 (range 2.8-4.5) mSv compared with 1.5 mSv for IVU. Ureteric calculi were detected in 43 patients: CT and IVU detected 40 (93%) ureteric calculi. CT identified other lesions causing symptoms in five patients and identified renal calculi in 24 patients. IVU identified renal calculi in six patients and made false positive diagnosis of renal calculi in seven patients. Mean examination time for CT was 5 minutes and for IVU was 80 minutes. CT examination at reduced exposure factors maintains the diagnostic accuracy recorded in other series. Copyright 2001 The Royal College of Radiologists.

  1. The economics of cardiac biomarker testing in suspected myocardial infarction.

    Science.gov (United States)

    Goodacre, Steve; Thokala, Praveen

    2015-03-01

    Suspected myocardial infarction (MI) is a common reason for emergency hospital attendance and admission. Cardiac biomarker measurement is an essential element of diagnostic assessment of suspected MI. Although the cost of a routinely available biomarker may be small, the large patient population and consequences in terms of hospital admission and investigation mean that the economic impact of cardiac biomarker testing is substantial. Economic evaluation involves comparing the estimated costs and effectiveness (outcomes) of two or more interventions or care alternatives. This process creates some difficulties with respect to cardiac biomarkers. Estimating the effectiveness of cardiac biomarkers involves identifying how they help to improve health and how we can measure this improvement. Comparison to an appropriate alternative is also problematic. New biomarkers may be promoted on the basis of reducing hospital admission or length of stay, but hospital admission for low risk patients may incur significant costs while providing very little benefit, making it an inappropriate comparator. Finally, economic evaluation may conclude that a more sensitive biomarker strategy is more effective but, by detecting and treating more cases, is also more expensive. In these circumstances it is unclear whether we should use the more effective or the cheaper option. This article provides an introduction to health economics and addresses the specific issues relevant to cardiac biomarkers. It describes the key concepts relevant to economic evaluation of cardiac biomarkers in suspected MI and highlights key areas of uncertainty and controversy. Copyright © 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  2. Limitation of personal freedom by detention of suspect

    Directory of Open Access Journals (Sweden)

    Knežević Saša

    2011-01-01

    Full Text Available The right of personal freedom is one of the most important right from the set of basic human rights and freedoms, contained in the most important acts of international legal character, and the constitutions of states based on the rule of law. This right is directly related to the very human existence, and, therefore, it is necessary to make its legal articulation. Personal freedom means the right to security of the citizen, that he will not be arrested and detained in prison by the state authorities, as well as the right to be free to move and inhabit. However, from the very nature of Criminal Law protection of social values, arises the need to limit the right to personal freedom in exceptional circumstances, including the detention of the suspect. Keeping the suspect is a measure of procedural compulsion, by which, through the police decision, detained prison is temporarily imprisoned, for gathering information and hearing. The basic principles of humanity require that the detained suspect retains all the rights, derived from the principle of personal liberty.

  3. MIBG in the evaluation of suspected pheochromocytoma: Mayo Clinic experience

    Energy Technology Data Exchange (ETDEWEB)

    Brown, M.L.; Sheps, S.G.; Sizemore, G.; Swensen, S.J.; Gharib, H.; Grant, C.S.; van Heerden, J.A.

    1984-01-01

    Work done at the University of Michigan has shown that I-131 metaiodobenzylguanidine (MIBG) is an effective agent for the diagnosis and localization of pheochromocytoma. A recent report questioned the sensitivity of this test. In 1983, 40 patients at Mayo Clinic had 42 scans during the workup of suspected spontaneous pheochromocytoma or metastatic pheochromocytoma. All patients were given 500 ..mu..Ci I-131 MIBG supplied by the University of Michigan. The final diagnosis of pheochromocytoma (true positive (TP) and false negative (FN) and false positive (FP)) was made by surgery and pathology. True negative (TN) diagnosis was made by normal plasma and urinary catecholamines, and in many patients CT. There were 15 TP studies (six spontaneous pheochrocytoma, nine metastatic or recurrent pheochromoctyoma), and 22 TN studies. There was one FP study of recurrent paraganglioma near the bladder (CT was also FP) and four FN studies (two spontaneous and two metastatic) where one CT was also FN. This results in a sensitivity of 79%, specificity of 96%, and accuracy of 88%. MIBG is very useful in the workup of patients with known or suspected recurrent or metastatic pheochromocytoma and is helpful in the evaluation of the patient suspected of having a spontaneous pheochromocytoma when CT is normal.

  4. Geo satellite attitude and orbit control: fixed orbit control thrasters

    OpenAIRE

    Ermoshkin, Yu; V. Raevsky; Urusov, V.

    2009-01-01

    The paper describes the enhanced application ofhigh-economical electro-jet orbit control thrusters for geostationary satellites; in particular, generation of controlling moments to the benefit of satellite attitude determination and control subsystems in the course of orbit control maneuvers ongoing. The scheme with thrusters fixed on a satellite body is analyzed. Possible orbit control session procedures are proposed on the basis of controlling moments generation. Advantages and disadvantage...

  5. Ultrasonography for suspected deep vein thrombosis: how useful is single-point augmentation?

    Energy Technology Data Exchange (ETDEWEB)

    McQueen, A.S. [Department of Radiology, Freeman Hospital, Newcastle upon Tyne (United Kingdom)], E-mail: andrewmcqueen7@hotmail.com; Elliott, S.T. [Department of Radiology, Freeman Hospital, Newcastle upon Tyne (United Kingdom); Keir, M.J. [Department of Medical Physics, Royal Victoria Infirmary, Newcastle upon Tyne (United Kingdom)

    2009-02-15

    Aims: To assess the role of single-point augmentation of spectral Doppler flow in the diagnosis of acute deep vein thrombosis (DVT). Secondary objectives included identifying the augmentation response in non-DVT diagnoses. Methods: Patients attending the ultrasound departments of two hospitals for investigation of suspected acute DVT during an 8-month period were recruited to the study group. Spectral Doppler assessment of the superficial femoral vein was recorded during Valsalva and calf compression manoeuvres in the asymptomatic and symptomatic legs. The Doppler waveforms from the symptomatic limb were characterized as 'normal' or 'abnormal' by the operator. Standard compression ultrasonography of the symptomatic leg was then performed with the presence of DVT or an alternative diagnosis documented. Results: One hundred and sixty-seven patients underwent ultrasound examinations using the study methodology. Nine patients were subsequently excluded due to bilateral DVT or inability to tolerate calf compression. The mean age of the remaining 158 patients was 65.4 years with 28 DVTs identified (18% of patients). Calf compression elicited a normal response in 118/130 of non-DVT examinations (specificity 91%) and an abnormal response in 18/28 DVT examinations (sensitivity 64%). Diminished or absent augmentation was identified in alternative diagnoses that included haematoma and Baker's cyst. Conclusions: This study demonstrates that single-point augmentation has a low sensitivity in suspected lower-limb DVT, and that the majority of undetected DVTs are isolated to the calf veins. An abnormal augmentation response is a poor predictor of lower-limb DVT as alternative diagnoses can produce diminished or reduced augmentation. Therefore, single-point augmentation does not add to the standard compression ultrasound examination for suspected DVT and should not be routinely performed.

  6. Predictors of bacteremia in emergency department patients with suspected infection.

    Science.gov (United States)

    Chase, Maureen; Klasco, Richard S; Joyce, Nina R; Donnino, Michael W; Wolfe, Richard E; Shapiro, Nathan I

    2012-11-01

    The goal of this study is to identify clinical variables associated with bacteremia. Such data could provide a rational basis for blood culture testing in emergency department (ED) patients with suspected infection. This is a secondary analysis of a prospective cohort of ED patients with suspected infection. Data collected included demographics, vital signs, medical history, suspected source of infection, laboratory and blood culture results and outcomes. Bacteremia was defined as a positive blood culture by Centers for Disease Control criteria. Clinical variables associated with bacteremia on univariate logistic regression were entered into a multivariable model. There were 5630 patients enrolled with an average age of 59.9 ± 19.9 years, and 54% were female. Blood cultures were obtained on 3310 (58.8%). There were 409 (12.4%) positive blood cultures, of which 68 (16.6%) were methicillin-resistant Staphylococcus aureus (MRSA) and 161 (39.4%) were Gram negatives. Ten covariates (respiratory failure, vasopressor use, neutrophilia, bandemia, thrombocytopenia, indwelling venous catheter, abnormal temperature, suspected line or urinary infection, or endocarditis) were associated with all-cause bacteremia in the final model (c-statistic area under the curve [AUC], 0.71). Additional factors associated with MRSA bacteremia included end-stage renal disease (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.9-7.8) and diabetes (OR, 2.0; 95% CI, 1.1-3.6) (AUC, 0.73). Factors strongly associated with Gram-negative bacteremia included vasopressor use in the ED (OR, 2.8; 95% CI, 1.7-4.6), bandemia (OR, 3.5; 95% CI, 2.3-5.3), and suspected urinary infection (OR, 4.0; 95% CI, 2.8-5.8) (AUC, 0.75). This study identified several clinical factors associated with bacteremia as well as MRSA and Gram-negative subtypes, but the magnitude of their associations is limited. Combining these covariates into a multivariable model moderately increases their predictive value. Copyright

  7. Usefulness of dynamic magnetic resonance imaging in the diagnosis of orbital tumors

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Hiroshi; Kotake, Fumio; Muramatsu, Ryuji; Usui, Masahiko; Ebihara, Yoshiro [Tokyo Medical Coll. (Japan)

    1997-05-01

    We studied four cases of orbital tumor by dynamic magnetic resonance imaging (MRI). The series comprised one case each of cavernous hemangioma, hemangiopericytoma, hemangioendothelioma and orbital schwannoma. Cavernous hemangioma showed gradual enhancement from the tumor margin, resulting in intense diffuse staining of the tumor mass in the late phase. Hemangiopericytoma showed rapid staining of the entire tumor. Hemangioendothelioma showed minimal staining of the tumor margin. Orbital schwannoma showed diffuse and rapid staining of the entire tumor. While postoperative recurrence was suspected in this case by standard MRI, dynamic MRI was suggestive of nonspecific scarring. Dynamic MRI was thus useful in the differential diagnosis of orbital tumors and in the evaluation of postoperative changes. (author)

  8. Klebsiella pneumoniae orbital cellulitis with extensive vascular occlusions in a patient with type 2 diabetes.

    Science.gov (United States)

    Yang, Sae Jeong; Park, Soo Yeon; Lee, Yun Jeong; Kim, Hee Young; Seo, Ji A; Kim, Sin Gon; Choi, Dong Seop

    2010-03-01

    A 39-year-old woman visited the emergency room complaining of right eye pain and swelling over the preceding three days. The ophthalmologist's examination revealed orbital cellulitis and diabetic retinopathy in the right eye, although the patient had no prior diagnosis of diabetes. It was therefore suspected that she had diabetes and orbital cellulitis, and she was started on multiple antibiotic therapies initially. She then underwent computed tomography scans of the orbit and neck and magnetic resonance imaging of the brain. These studies showed an aggravated orbital cellulitis with abscess formation, associated with venous thrombophlebitis, thrombosis of the internal carotid artery, and mucosal thickening of maxillary sinus with multiple paranasal abscesses. Three days later, initial blood culture grew Klebsiella pneumoniae. She recovered after incision and drainage and antibiotic therapy for 37 days.

  9. The accuracy of orbit estimation for the low-orbit satellites LARETS and WESTPAC

    Science.gov (United States)

    Rutkowska, Milena

    The LARETS satellite was launched on September 26, 2004, into a circular orbit at an altitude of 690 km and with an inclination of 98.2°. This mission is a successor to the WESTPAC satellite which was launched to an altitude of 835 km six years before. The study is based on the observations taken by the global network of laser stations during the period from December 30, 2003 to March 17, 2004 for LARETS. This study is aimed at the precise orbit computation of LARETS. The experience acquired during the orbit estimation of WESTPAC was applied to the orbit investigation of LARETS. The WESTPAC was merely used for reference and initial parameters of the force model [Rutkowska, M., Noomenn, R., Global orbit analysis of the satellite WESTPAC, Adv. Space Res., 30(2), 265-270, 2002]. The orbit of LARETS was estimated with an rms-of-fit to the SLR measurements of 3.9 cm, using the following computation model: the CSR TEG-4 gravity field up to degree and order (200,200), the Ray tide model, the MSIS86 model for atmospheric density [Hedin, A.E., MSIS-86 Thermospheric Model, J. Geophys. Res., 92 (A5), 4649-4662, 1987], and the solution of 8-hourly CD-values. It has been verified that the modeling of the gravity field up to degree and order (100,100) which gives the same rms-of-fit value. Estimated orbits for both satellites are compared to each other in Fig. 2. All computations are performed with the NASA program GEODYN II [Eddy, W.F, McCarthy, J.J., Pavlis, D.E., Marshall, J.A., Luthce, S.B., Tsaoussi, L.S., GEODYN II System Operations Manual, vol. 1-5, ST System Corp., Lanham MD, USA, 1990].

  10. ExoMars Trace Gas Orbiter provides atmospheric data during Aerobraking into its final orbit

    Science.gov (United States)

    Svedhem, Hakan; Vago, Jorge L.; Bruinsma, Sean; Müller-Wodarg, Ingo; ExoMars 2016 Team

    2017-10-01

    After the arrival of the Trace Gas Orbiter (TGO) at Mars on 19 October 2016 a number of initial orbit change manoeuvres were executed and the spacecraft was put in an orbit with a 24 hour period and 74 degrees inclination. The spacecraft and its four instruments were thoroughly checked out after arrival and a few measurements and images were taken in November 2016 and in Feb-March 2017. The solar occultation observations have however not yet been possible due to lack of the proper geometry.On 15 March a long period of aerobraking to reach the final 400km semi-circular frozen orbit (370x430km, with a fixed pericentre latitude). This orbit is optimised for the payload observations and for the communication relay with the ExoMars Rover, due to arrive in 2021.The aerobraking is proceeding well and the final orbit is expected to be reached in April 2018. A large data set is being acquired for the upper atmosphere of Mars, from the limit of the sensitivity of the accelerometer, down to lowest altitude of the aerobraking at about 105km. Initial analysis has shown a highly variable atmosphere with a slightly lower density then predicted by existing models. Until the time of the abstract writing no dust storms have been observed.The ExoMars programme is a joint activity by the European Space Agency(ESA) and ROSCOSMOS, Russia. ESA is providing the TGO spacecraft and Schiaparelli (EDM) and two of the TGO instruments and ROSCOSMOS is providing the Proton launcher and the other two TGO instruments. After the arrival of the ExoMars 2020 mission, consisting of a Rover and a Surface platform also launched by a Proton rocket, the TGO will handle the communication between the Earth and the Rover and Surface Platform through its (NASA provided) UHF communication system.

  11. Period proliferation in periodic states in cyclically sheared jammed solids

    Science.gov (United States)

    Lavrentovich, Maxim O.; Liu, Andrea J.; Nagel, Sidney R.

    2017-08-01

    Athermal disordered systems can exhibit a remarkable response to an applied oscillatory shear: After a relatively few shearing cycles, the system falls into a configuration that had already been visited in a previous cycle. After this point the system repeats its dynamics periodically despite undergoing many particle rearrangements during each cycle. We study the behavior of orbits as we approach the jamming point in simulations of jammed particles subject to oscillatory shear at fixed pressure and zero temperature. As the pressure is lowered, we find that it becomes more common for the system to find periodic states where it takes multiple cycles before returning to a previously visited state. Thus, there is a proliferation of longer periods as the jamming point is approached.

  12. Lyapunov Orbits in the Jupiter System Using Electrodynamic Tethers

    Science.gov (United States)

    Bokelmann, Kevin; Russell, Ryan P.; Lantoine, Gregory

    2013-01-01

    Various researchers have proposed the use of electrodynamic tethers for power generation and capture from interplanetary transfers. The effect of tether forces on periodic orbits in Jupiter-satellite systems are investigated. A perturbation force is added to the restricted three-body problem model and a series of simplifications allows development of a conservative system that retains the Jacobi integral. Expressions are developed to find modified locations of equilibrium positions. Modified families of Lyapunov orbits are generated as functions of tether size and Jacobi integral. Zero velocity curves and stability analyses are used to evaluate the dynamical properties of tether-modified orbits.

  13. Unexpected climatic impacts of orbital forcing out of the Quaternary

    Science.gov (United States)

    Ramstein, G.; Zhang, Z.; Le Hir, G.; Contoux, C.; Donnadieu, Y.; Dumas, C.; Schuster, M.; Li, C.

    2016-12-01

    For Quaternary, the impact of orbital variations on climate is huge and well documented. Especially, during the last million years, drastic climate changes occurred, consisting in transitions from glacial to interglacial periods driven by changes in 65°N summer insolation with 100 kyrs periodicity. Nevertheless, the imprint of so-called Milankovic forcings has also been found for Tertiary and Secondary. For both periods, the climatic imprints of orbital forcings are recorded in a warm world without ice sheet. Here, we show through simulation studies the large impact of orbital forcing in very different geological contexts. The first and most striking result depicts the role of insolation changes during the melting of the Marinoan snowball [635 Ma] (Benn et al, Nature Geoscience 2015). This is one of the oldest imprints of orbital forcing on climate. Our result solved a long lasting controversy concerning the melting of the last snowball episode between a huge deglaciation at very high CO2 level and data showing glacial/interglacial cycles occurring during that melting. Our modelling studies focusing on Svalbard high resolution records demonstrate that the glacial/fluvial oscillation was related to orbital forcing in a context of very high CO2 level. Much more recently, during the Tortonian period [11-7 Ma], the orbital cycles shaped the environment and drove the hominin dispersal in Africa. During Tortonian, the ultimate shrinkage of a huge epicontinental sea, that extended from Eastern Europe to Western Asia, has been shown to produce major changes on Asian monsoon (Ramstein et al, Nature, 1997) and triggered the onset of Sahara desert (Zhang et al, Nature 2014). Moreover, this shrinkage drastically enhanced the climate response to orbital changes at the emergence of early hominins in North Africa. Through these two illustrations,we pointed out very different climatic impacts of orbital forcing out of Quaternary.

  14. Quasi-periodicity in relative quasi-periodic tori

    Science.gov (United States)

    Fassò, Francesco; García-Naranjo, Luis C.; Giacobbe, Andrea

    2015-10-01

    At variance from the cases of relative equilibria and relative periodic orbits of dynamical systems with symmetry, the dynamics in relative quasi-periodic tori (namely, subsets of the phase space that project to an invariant torus of the reduced system on which the flow is quasi-periodic) is not yet completely understood. Even in the simplest situation of a free action of a compact and abelian connected group, the dynamics in a relative quasi-periodic torus is not necessarily quasi-periodic. It is known that quasi-periodicity of the unreduced dynamics is related to the reducibility of the reconstruction equation, and sufficient conditions for it are virtually known only in a perturbation context. We provide a different, though equivalent, approach to this subject, based on the hypothesis of the existence of commuting, group-invariant lifts of a set of generators of the reduced torus. Under this hypothesis, which is shown to be equivalent to the reducibility of the reconstruction equation, we give a complete description of the structure of the relative quasi-periodic torus, which is a principal torus bundle whose fibers are tori of a dimension which exceeds that of the reduced torus by at most the rank of the group. The construction can always be done in such a way that these tori have minimal dimension and carry ergodic flow.

  15. Orbital science's 'Bermuda Triangle'

    Science.gov (United States)

    Sherrill, Thomas J.

    1991-02-01

    The effects of a part of the inner Van Allen belt lying closest to the earth, known as the South Atlantic Anomaly (SAA) upon spacecraft including the Hubble Space Telescope (HST), are discussed. The area consists of positively charged ions and electrons from the Van Allen Belt which become trapped in the earth's dipole field. Contor maps representing the number of protons per square centimeter per second having energies greater than 10 million electron volts are presented. It is noted that the HST orbit causes it to spend about 15 percent of its time in the SAA, but that, unlike the experience with earlier spacecraft, the satellite's skin, internal structure, and normal electronic's packaging provides sufficient protection against eletrons, although some higher energy protons still get through. Various charged particle effects which can arise within scientific instruments including fluorescence, Cerenkov radiation, and induced radioactivity are described.

  16. Orbital Eccrine Hidrocystoma

    Directory of Open Access Journals (Sweden)

    Deniz Marangoz

    2016-10-01

    Full Text Available A 29-year-old female patient presented with a painless mass on her upper eyelid medially. She noticed the mass 4 years earlier and it had increased in size over time. She had no diplopia, eyelid swelling, skin lesion overlying the mass, or visual disturbances. On ocular examination, eye movements and funduscopy were normal. The mass was movable and painless with palpation. Magnetic resonance imaging with contrast showed a 12x8x7 mm well-circumscribed cystic lesion with no contrast dye appearance. Surgical removal was performed delicately and no capsular rupture occured. Pathological examination revealed an eccrine hidrocystoma. Our aim is to underline that eccrine hidrocystoma should be included in differential diagnosis of orbital masses.

  17. The conservation of orbital symmetry

    CERN Document Server

    Woodward, R B

    2013-01-01

    The Conservation of Orbital Symmetry examines the principle of conservation of orbital symmetry and its use. The central content of the principle was that reactions occur readily when there is congruence between orbital symmetry characteristics of reactants and products, and only with difficulty when that congruence does not obtain-or to put it more succinctly, orbital symmetry is conserved in concerted reaction. This principle is expected to endure, whatever the language in which it may be couched, or whatever greater precision may be developed in its application and extension. The book ope

  18. CDDIS_DORIS_products_orbit

    Data.gov (United States)

    National Aeronautics and Space Administration — Precise satellite orbits derived from analysis of Doppler Orbitography by Radiopositioning Integrated on Satellite (DORIS) data. These products are the generated by...

  19. Prognostic importance of quantitative echocardiographic evaluation in patients suspected of first non-massive pulmonary embolism

    DEFF Research Database (Denmark)

    Kjaergaard, Jesper; Schaadt, Bente Krogsgaard; Lund, Jens Otto

    2008-01-01

    AIMS: Patients suspected of acute pulmonary embolism (PE) frequently undergo echocardiography as a part of the initial work-up. Prognostic implication of routine echocardiography in patients suspected of PE remain to be established. METHODS AND RESULTS: Transthoracic echocardiography, including...

  20. The prevalence of marijuana in suspected impaired driving cases in Washington state.

    Science.gov (United States)

    Couper, Fiona J; Peterson, Brianna L

    2014-10-01

    In December 2012, the possession and private use of limited quantities of marijuana and marijuana products became legal in the state of Washington. At the same time, the state's driving under the influence statutes were amended to include a per se level of 5 ng/mL delta(9)-tetrahydrocannabinol (THC) in whole blood for drivers aged 21 years and older. The aim of this study was to assess the effect of marijuana legalization on the prevalence of marijuana in suspected impaired driving cases. The prevalence of both active THC and its metabolite carboxy-THC detected in such cases pre-legalization was compared with the prevalence post-legalization. In 2009-2012, the average yearly percentage of cases positive for THC and carboxy-THC was 19.1% (range: 18.2-20.2%) and 27.9% (range: 26.3-28.6%), respectively. In 2013, the percentages had significantly increased to 24.9 and 40.0%, respectively (P 5 ng/mL over the 5-year period. The prevalence of alcohol and the majority of other drugs in this same population of suspected impaired drivers submitted for testing did not change during this same 5-year period-marijuana was the only drug to show such an increase in frequency. Further, this observed increase remained after the data had been normalized to account for changes in laboratory testing procedures that occurred during this time period. Future studies need be conducted to ascertain whether the observed increase has had any effect on the incidence of crashes, serious injuries and/or traffic fatalities. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Diagnostic efficacy and therapeutic impact of computed tomography in the evaluation of clinically suspected otosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Dudau, Cristina [King' s College Hospital NHS Foundation Trust, Department of Neuroradiology, London (United Kingdom); Salim, Fakhruddin; Jiang, Dan [Department of Otolaryngology, Head and Neck Surgery, Auditory Implantation Centre, London (United Kingdom); Connor, Steve E.J. [Department of Radiology, Guy' s and St Thomas' NHS Foundation Trust, London (United Kingdom)

    2017-03-15

    To assess the diagnostic efficacy and therapeutic impact of CT in evaluating patients with clinically suspected otosclerosis. CT scans performed over a 5-year period for clinically suspected otosclerosis were retrospectively reviewed. CT diagnoses were correlated with subsequent surgical management. For otosclerosis positive cases, clinically significant extensions of otosclerosis were correlated with audiometry and the diagnosis was correlated with surgical findings. Of 259 CT studies, 46 % of patients were positive, 49 % negative and 5 % equivocal for otosclerosis. A relevant alternative CT diagnosis was evident in 33 % of the negative studies. One targeted surgery was performed for every four CT studies. CT outcome influenced the decision to perform stapedectomy in 41 % CT-positive versus 4 % CT-negative patients. CT-positive ears for otosclerosis could not be predicted from baseline clinical or audiometric criteria. Those with endosteal extension demonstrated lower bone conduction thresholds presurgically. The positive predictive value of CT diagnosis of otosclerosis was 100 %. CT demonstrated a high rate of clinically relevant diagnoses in both CT-positive and -negative for otosclerosis patients, and this frequently influenced surgical management. CT also added value by demonstrating relevant extensions of the otosclerotic foci, some of which were predictive of audiometric parameters. (orig.)

  2. Orbital Evolution and Orbital Phase Resolved Spectroscopy of the ...

    Indian Academy of Sciences (India)

    tra in the 3–20 keV energy range were fitted with a power law and a high ... acceleration method and also depends on any anisotropy in the stellar wind structure. .... Orbital Evolution and Orbital Phase Resolved Spectroscopy. 415. Figure 3. (a) Pulse arrival time delays measured from the RXTE-PCA observation in 2003,.

  3. [Value of laparoscopic surgery in the diagnosis of suspected gestational trophoblastic neoplasia cases with uterine mass].

    Science.gov (United States)

    Li, Xiaochuan; Feng, Fengzhi; Xiang, Yang; Wan, Xirun; Ren, Tong; Yang, Junjun

    2015-12-01

    To evaluate the value of laparoscopic surgery in the diagnosis of suspected gestational trophoblastic neoplasia (GTN) cases with uterine mass. The clinical characteristics of patients underwent laparoscopic surgery for a suspected diagnosis of GTN with uterine mass in Peking Union Medical College Hospital from November 2009 to November 2014 were retrospectively reviewed and analyzed. GTN and other pregnant-related disease were definitely diagnosed by pathological findings. The prognoses of the GTN cases were also investigated. Sixty-two patients with a suspected diagnosis of GTN with uterine mass were studied. Among them, 17 cases were definitely diagnosed as GTN, including 8 choriocarcinoma, 5 invasive mole and 4 placental site trophoblastic tumor (PSTT). The other 45 cases were diagnosed as benign pregnancy-related diseases, including 29 cornual pregnancy, 6 cesarean scar pregnancy, 5 placenta accreta, 4 intramural uterine pregnancy and 1 exaggerated placental site. There were no significantly differences between the two groups in average age, preoperative value or tendency of β-hCG, and location or size of lesions (P>0.05). More GTN patients showed a history of hydatidiform mole [5/17 vs 4% (2/45) , P>0.05], and more patients with benign pregnancy-related disease showed a history of cesarean section [38% (17/45) vs 1/17, P>0.05]. No serious perioperative complication was found in these patients received laparoscopic surgery. All GTN patients achieved complete remission by chemotherapy later. Except for 1 case loss, no recurrence was found in 11 low-risk stage I cases with an average follow-up period of 11- 66 months, 1 high-risk stage I case with a follow-up period of 61 months and 4 cases PSTT with a follow-up period of 13-66 months. There were some atypical GTN cases with uterine mass, which were difficult to be differentiated from benign pregnancy-related diseases according to the clinical characteristics. Laparoscopic surgery with a pathologic diagnosis

  4. Orbital decompression for Graves' orbitopathy in England

    Science.gov (United States)

    Perros, P; Chandler, T; Dayan, C M; Dickinson, A J; Foley, P; Hickey, J; MacEwen, C J; Lazarus, J H; McLaren, J; Rose, G E; Uddin, J M; Vaidya, B

    2012-01-01

    Aims The purpose of this study was to obtain data on orbital decompression procedures performed in England, classed by hospital and locality, to evaluate regional variation in care. Methods Data on orbital decompression taking place in England over a 2-year period between 2007 and 2009 were derived from CHKS Ltd and analysed by the hospital and primary care trust. Results and conclusions In all, 44% of these operations took place in hospitals with an annual workload of 10 or fewer procedures. Analysis of the same data by primary care trust suggests an almost 30-fold variance in the rates of decompression performed per unit population. Expertise available to patients with Graves' orbitopathy and rates of referral for specialist care in England appears to vary significantly by geographic location. These data, along with other outcome measures, will provide a baseline by which progress can be judged. PMID:22157920

  5. Orbital Chondroma: A rare mesenchymal tumor of orbit

    Directory of Open Access Journals (Sweden)

    Ruchi S Kabra

    2015-01-01

    Full Text Available While relatively common in the skeletal system, cartilaginous tumors are rarely seen originating from the orbit. Here, we report a rare case of an orbital chondroma. A 27-year-old male patient presented with a painless hard mass in the superonasal quadrant (SNQ of left orbit since 3 months. On examination, best-corrected visual acuity of both eyes was 20/20, with normal anterior and posterior segment with full movements of eyeballs and normal intraocular pressure. Computerized tomography scan revealed well defined soft tissue density lesion in SNQ of left orbit. Patient was operated for anteromedial orbitotomy under general anesthesia. Mass was excised intact and sent for histopathological examination (HPE. HPE report showed lobular aggregates of benign cartilaginous cells with mild atypia suggesting of benign cartilaginous tumor - chondroma. Very few cases of orbital chondroma have been reported in literature so far.

  6. Icare rebound tonometry in children with known and suspected glaucoma.

    Science.gov (United States)

    Flemmons, Meghan S; Hsiao, Ya-Chuan; Dzau, Jacqueline; Asrani, Sanjay; Jones, Sarah; Freedman, Sharon F

    2011-04-01

    Accurate intraocular pressure (IOP) measurement, important in managing pediatric glaucoma, often presents challenges. The Icare rebound tonometer shows promise for screening healthy children and has been reported comparable with Goldmann applanation in adults with glaucoma. The purpose of this study was to evaluate the Icare tonometer against Goldmann applanation for clinic IOP measurement in pediatric glaucoma. This was a prospective study comparing Icare versus Goldmann tonometry in pediatric glaucoma. Children with known or suspected glaucoma were recruited from scheduled clinic visits. IOP was measured with the Icare tonometer by a clinician and subsequently measured with Goldmann applanation tonometry (GAT) by a different single masked clinician. A total of 71 eyes of 71 children with known or suspected glaucoma were included. IOP by GAT ranged from 9 to 36 mm Hg. Icare readings ranged from 11 to 44 mm Hg. Mean difference between Icare and GAT was 2.3 ± SD 3.7 mm Hg, p IOPs were within ± 3 mm Hg of GAT in 63%. Icare IOPs were ≥GAT IOPs in 75%. The following factors were not associated with Icare IOPs greater than GAT: child's age, glaucoma diagnosis, strabismus, nystagmus, central corneal thickness, Icare instrument-reported reliability, number of glaucoma surgeries or medications, corneal abnormalities, and visual acuity. IOP by Icare tonometry was within 3 mm Hg of IOP by GAT in 63% and greater than GAT in 75%. This device may be reasonable to estimate IOP in selected children with known or suspected glaucoma whose IOP cannot otherwise be obtained in clinic; however, correlation of Icare IOPs with clinical findings must continue to be considered in each case. Copyright © 2011 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

  7. Herbal hepatotoxicity: suspected cases assessed for alternative causes.

    Science.gov (United States)

    Teschke, Rolf; Schulze, Johannes; Schwarzenboeck, Alexander; Eickhoff, Axel; Frenzel, Christian

    2013-09-01

    Alternative explanations are common in suspected drug-induced liver injury (DILI) and account for up to 47.1% of analyzed cases. This raised the question of whether a similar frequency may prevail in cases of assumed herb-induced liver injury (HILI). We searched the Medline database for the following terms: herbs, herbal drugs, herbal dietary supplements, hepatotoxic herbs, herbal hepatotoxicity, and herb-induced liver injury. Additional terms specifically addressed single herbs and herbal products: black cohosh, Greater Celandine, green tea, Herbalife products, Hydroxycut, kava, and Pelargonium sidoides. We retrieved 23 published case series and regulatory assessments related to hepatotoxicity by herbs and herbal dietary supplements with alternative causes. The 23 publications comprised 573 cases of initially suspected HILI; alternative causes were evident in 278/573 cases (48.5%). Among them were hepatitis by various viruses (9.7%), autoimmune diseases (10.4%), nonalcoholic and alcoholic liver diseases (5.4%), liver injury by comedication (DILI and other HILI) (43.9%), and liver involvement in infectious diseases (4.7%). Biliary and pancreatic diseases were frequent alternative diagnoses (11.5%), raising therapeutic problems if specific treatment is withheld; pre-existing liver diseases including cirrhosis (9.7%) were additional confounding variables. Other diagnoses were rare, but possibly relevant for the individual patient. In 573 cases of initially assumed HILI, 48.5% showed alternative causes unrelated to the initially incriminated herb, herbal drug, or herbal dietary supplement, calling for thorough clinical evaluations and appropriate causality assessments in future cases of suspected HILI.

  8. Benefits of sonography in diagnosing suspected uncomplicated acute diverticulitis.

    Science.gov (United States)

    King, Welfur C; Shuaib, Waqas; Vijayasarathi, Arvind; Fajardo, Carlos G; Cabrera, Waldo E; Costa, Juan L

    2015-01-01

    Despite evidence demonstrating equivalent accuracy of sonography and computed tomography (CT) in the workup of mild/uncomplicated acute diverticulitis, CT is overwhelmingly performed as the initial diagnostic test, particularly in the acute setting. Our study evaluated potential radiation and turnaround time savings associated with performing sonography instead of CT as the initial diagnostic examination in the workup of suspected uncomplicated acute diverticulitis. We retrospectively reviewed medical records from January 2010 to December 2012 for patients presenting with clinical symptoms of acute diverticulitis. Patients were categorized as a whole and subgrouped by age (>40 and 40 years and 121 diverticulitis. © 2015 by the American Institute of Ultrasound in Medicine.

  9. A Suspected Pelvic Aneurysmal Bone Cyst in Pregnancy

    Directory of Open Access Journals (Sweden)

    Rayan Elkattah

    2013-01-01

    Full Text Available Albeit rare, the majority of identified bone lesions in pregnancy spare the pelvis. Once encountered with a pelvic bone lesion in pregnancy, the obstetrician may face a challenging situation as it is difficult to determine and predict the effects that labor and parturition impart on the pelvic bones. Bone changes and pelvic bone fractures have been well documented during childbirth. The data regarding clinical outcomes and management of pregnancies complicated by pelvic ABCs is scant. Highly suspected to represent an aneurysmal bone cyst, the clinical evaluation of a pelvic lesion in the ilium of a pregnant individual is presented, and modes of delivery in such a scenario are discussed.

  10. Patch Testing in Suspected Allergic Contact Dermatitis to Cosmetics

    OpenAIRE

    Pramod Kumar; Rekha Paulose

    2014-01-01

    Background. Increasing use of cosmetics has contributed to a rise in the incidence of allergic contact dermatitis (ACD) to cosmetics. It is estimated that 1–5.4% of the population is sensitized to a cosmetic ingredient. Patch testing helps to confirm the presence of an allergy and to identify the actual allergens which are chemical mixtures of various ingredients. Objectives. The aims of this study are to perform patch testing in suspected ACD to cosmetics and to identify the most common alle...

  11. The TWA 3 Young Triple System: Orbits, Disks, Evolution

    Energy Technology Data Exchange (ETDEWEB)

    Kellogg, Kendra [Department of Physics and Astronomy, The University of Western Ontario, London, ON N6A 3K7 (Canada); Prato, L.; Avilez, I.; Wasserman, L. H.; Levine, S. E.; Bosh, A. S. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Torres, Guillermo [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Schaefer, G. H. [The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, CA 91023 (United States); Ruíz-Rodríguez, D. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Bonanos, Alceste Z. [IAASARS, National Observatory of Athens, 15236 Penteli (Greece); Guenther, E. W. [Thüringer Landessternwarte Tautenburg, D-07778 Tautenburg (Germany); Neuhäuser, R. [Astrophysikalisches Institut und Universitäts-Sternwarte, FSU Jena, Schillergäßchen 2-3, D-07745 Jena (Germany); Morzinski, Katie M.; Close, Laird; Hinz, Phil; Males, Jared R. [Steward Observatory, University of Arizona, 933 N. Cherry Ave, Tucson, AZ 85721 (United States); Bailey, Vanessa, E-mail: kkellogg@uwo.ca, E-mail: lprato@lowell.edu [Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics, Stanford University, Stanford, CA, 94305 (United States)

    2017-08-01

    We have characterized the spectroscopic orbit of the TWA 3A binary and provide preliminary families of probable solutions for the TWA 3A visual orbit, as well as for the wide TWA 3A–B orbit. TWA 3 is a hierarchical triple located at 34 pc in the ∼10 Myr old TW Hya association. The wide component separation is 1.″55; the close pair was first identified as a possible binary almost 20 years ago. We initially identified the 35-day period orbital solution using high-resolution infrared spectroscopy that angularly resolved the A and B components. We then refined the preliminary orbit by combining the infrared data with a reanalysis of our high-resolution optical spectroscopy. The orbital period from the combined spectroscopic solution is ∼35 days, the eccentricity is ∼0.63, and the mass ratio is ∼0.84; although this high mass ratio would suggest that optical spectroscopy alone should be sufficient to identify the orbital solution, the presence of the tertiary B component likely introduced confusion in the blended optical spectra. Using millimeter imaging from the literature, we also estimate the inclinations of the stellar orbital planes with respect to the TWA 3A circumbinary disk inclination and find that all three planes are likely misaligned by at least ∼30°. The TWA 3A spectroscopic binary components have spectral types of M4.0 and M4.5; TWA 3B is an M3. We speculate that the system formed as a triple, is bound, and that its properties were shaped by dynamical interactions between the inclined orbits and disk.

  12. Clinical and microbiological features of dientamoebiasis in patients suspected of suffering from a parasitic gastrointestinal illness: a comparison of Dientamoeba fragilis and Giardia lamblia infections

    NARCIS (Netherlands)

    Vandenberg, Olivier; Peek, Ron; Souayah, Hichem; Dediste, Anne; Buset, Michel; Scheen, Robert; Retore, Patricia; Zissis, Georges; van Gool, Tom

    2006-01-01

    To describe the clinical and microbiological features of Dientamoeba fragilis and Giardia lamblia infected patients, and to analyze the genetic variation of D. fragilis strains. For a period of two years, all stool samples collected from patients suspected of having a parasitic gastrointestinal

  13. Plasmablastic lymphoma mimicking orbital cellulitis.

    NARCIS (Netherlands)

    Barkhuysen, R.; Merkx, M.A.W.; Weijs, W.L.J.; Gerlach, N.L.; Berge, S.J.

    2008-01-01

    INTRODUCTION: Orbital cellulitis is an uncommon, potentially devastating condition that, when not promptly and adequately treated, can lead to serious sequelae. The presenting clinical signs are proptosis, swelling, ophthalmoplegia, pain and redness of the peri-orbital tissues. A number of cases

  14. Diffractive molecular-orbital tomography

    Science.gov (United States)

    Zhai, Chunyang; Zhu, Xiaosong; Lan, Pengfei; Wang, Feng; He, Lixin; Shi, Wenjing; Li, Yang; Li, Min; Zhang, Qingbin; Lu, Peixiang

    2017-03-01

    High-order-harmonic generation in the interaction of femtosecond lasers with atoms and molecules opens the path to molecular-orbital tomography and to probe the electronic dynamics with attosecond-Ångström resolutions. Molecular-orbital tomography requires both the amplitude and phase of the high-order harmonics. Yet the measurement of phases requires sophisticated techniques and represents formidable challenges at present. Here we report a scheme, called diffractive molecular-orbital tomography, to retrieve the molecular orbital solely from the amplitude of high-order harmonics without measuring any phase information. We have applied this method to image the molecular orbitals of N2, CO2, and C2H2 . The retrieved orbital is further improved by taking account the correction of Coulomb potential. The diffractive molecular-orbital tomography scheme, removing the roadblock of phase measurement, significantly simplifies the molecular-orbital tomography procedure and paves an efficient and robust way to the imaging of more complex molecules.

  15. Orbit Modeller - Virtual Astronomical Laboratory

    Science.gov (United States)

    Avdyushev, V. A.; Banshchikova, M. A.; Bordovitsyna, T. V.; Chuvashov, I. N.; Ryabova, G. O.

    2017-09-01

    We present a virtual astronomical laboratory project - "Orbit Modeller" (OM). This should be an interactive web-tool enabling one to simulate numerically the orbital motion of any celestial body within or beyond the solar system. Another function of OM is a repository of old observations and documents.

  16. Endoscopic treatment of orbital tumors.

    Science.gov (United States)

    Signorelli, Francesco; Anile, Carmelo; Rigante, Mario; Paludetti, Gaetano; Pompucci, Angelo; Mangiola, Annunziato

    2015-03-16

    Different orbital and transcranial approaches are performed in order to manage orbital tumors, depending on the location and size of the lesion within the orbit. These approaches provide a satisfactory view of the superior and lateral aspects of the orbit and the optic canal but involve risks associated with their invasiveness because they require significant displacement of orbital structures. In addition, external approaches to intraconal lesions may also require deinsertion of extraocular muscles, with subsequent impact on extraocular mobility. Recently, minimally invasive techniques have been proposed as valid alternative to external approaches for selected orbital lesions. Among them, transnasal endoscopic approaches, "pure" or combined with external approaches, have been reported, especially for intraconal lesions located inferiorly and medially to the optic nerve. The avoidance of muscle detachment and the shortness of the surgical intraorbital trajectory makes endoscopic approach less invasive, thus minimizing tissue damage. Endoscopic surgery decreases the recovery time and improves the cosmetic outcome not requiring skin incisions. The purpose of this study is to review and discuss the current surgical techniques for orbital tumors removal, focusing on endoscopic approaches to the orbit and outlining the key anatomic principles to follow for safe tumor resection.

  17. Generating realistic synthetic meteoroid orbits

    Science.gov (United States)

    Vida, Denis; Brown, Peter G.; Campbell-Brown, Margaret

    2017-11-01

    Context. Generating a synthetic dataset of meteoroid orbits is a crucial step in analysing the probabilities of random grouping of meteoroid orbits in automated meteor shower surveys. Recent works have shown the importance of choosing a low similarity threshold value of meteoroid orbits, some pointing out that the recent meteor shower surveys produced false positives due to similarity thresholds which were too high. On the other hand, the methods of synthetic meteoroid orbit generation introduce additional biases into the data, thus making the final decision on an appropriate threshold value uncertain. Aims. As a part of the ongoing effort to determine the nature of meteor showers and improve automated methods, it was decided to tackle the problem of synthetic meteoroid orbit generation, the main goal being to reproduce the underlying structure and the statistics of the observed data in the synthetic orbits. Methods. A new method of generating synthetic meteoroid orbits using the Kernel Density Estimation method is presented. Several types of approaches are recommended, depending on whether one strives to preserve the data structure, the data statistics or to have a compromise between the two. Results. The improvements over the existing methods of synthetic orbit generation are demonstrated. The comparison between the previous and newly developed methods are given, as well as the visualization tools one can use to estimate the influence of different input parameters on the final data.

  18. Density-orbital embedding theory

    NARCIS (Netherlands)

    Visscher, L.; Gritsenko, O.

    2010-01-01

    In the article density-orbital embedding (DOE) theory is proposed. DOE is based on the concept of density orbital (DO), which is a generalization of the square root of the density for real functions and fractional electron numbers. The basic feature of DOE is the representation of the total

  19. Be discs in binary systems - II. Misaligned orbits

    Science.gov (United States)

    Cyr, I. H.; Jones, C. E.; Panoglou, D.; Carciofi, A. C.; Okazaki, A. T.

    2017-10-01

    We use a smoothed particle hydrodynamics (SPH) code to examine the effects of misaligned binary companions on Be star discs. We systematically vary the degree of misalignment between the disc and the binary orbit, as well as the disc viscosity and orbital period to study their effects on the density in the inner and outer parts of the disc. We find that varying the degree of misalignment, the viscosity and the orbital period affects both the truncation radius and the density structure of the outer disc, while the inner disc remains mostly unaffected. We also investigate the tilting of the disc in the innermost part of the disc and find the tilt increases with radius until reaching a maximum around 5 stellar radii. The direction of the line of nodes, with respect to the equator of the central star, is found to be offset compared to the orbital line of nodes, and to vary periodically in time, with a period of half a orbital phase. We also compare the scaleheight of our discs with the analytical scaleheight of an isothermal disc, which increases with radius as r1.5. We find that this formula reproduces the scaleheight well for both aligned and misaligned systems but underestimates the scaleheight in regions of the disc where density enhancements develop.

  20. Plasmablastic lymphoma mimicking orbital cellulitis

    Science.gov (United States)

    Merkx, Matthias A. W.; Weijs, Willem L. J.; Gerlach, Niek L.; Bergé, Stefaan J.

    2008-01-01

    Introduction Orbital cellulitis is an uncommon, potentially devastating condition that, when not promptly and adequately treated, can lead to serious sequelae. The presenting clinical signs are proptosis, swelling, ophthalmoplegia, pain and redness of the peri-orbital tissues. A number of cases have been reported in which these symptoms have been mistakenly interpreted as being secondary to an orbital infection whilst, in fact, other pathology was present. Discussion We add another case in which, on clinical grounds and after radiological assessment and laboratory tests, a working diagnosis of orbital cellulitis of the left eye was made. It was only after histopathological analysis of a soft tissue specimen from the maxillary sinus that a diagnosis of an AIDS-related plasmablastic lymphoma was made. The patient was referred to the department of haematology where chemotherapeutic treatment for the lymphoma and the HIV infection was started. This case report adds another differential diagnosis of orbital cellulitis to the existing literature. PMID:18597126

  1. Investigation of suspected chronic fatigue syndrome/myalgic encephalopathy.

    Science.gov (United States)

    Owe, Jone Furlund; Næss, Halvor; Gjerde, Ivar Otto; Bødtker, Jørn Eilert; Tysnes, Ole-Bjørn

    2016-02-09

    Chronic fatigue is a frequently occurring problem in both the primary and specialist health services. The Department of Neurology at Haukeland University Hospital has established a standard assessment for patients referred with suspected CFS/ME. This study reports diagnoses and findings upon assessment, and considers the benefit of supplementary examinations. Diagnoses and findings from examinations of 365 patients assessed for suspected CFS/ME are retrospectively reported. A total of 48 patients (13.2%) were diagnosed with CFS/ME, while a further 18 patients (4.9%) were diagnosed with post-infectious fatigue. Mental and behavioural disorders were diagnosed in 169 patients (46.3%), and these represented by far the largest group. Serious, but unrecognised somatic illness was discovered in two patients, while changes of uncertain significance were identified by MRI and lumbar puncture in a few patients. Fatigue is a frequently occurring symptom in the population. Thorough somatic and psychiatric investigation is necessary before referral to the specialist health services. Mental disorders and reactions to life crises are common and important differential diagnoses for CFS/ME. Long waiting times in the specialist health services may result in delayed diagnosis for these patients.

  2. MRI diagnosis of suspected atlanto-occipital dissociation in childhood

    Energy Technology Data Exchange (ETDEWEB)

    Grabb, B.C.; Frye, T.A.; Hedlund, G.L.; Vaid, Y.N.; Royal, S.A. [Department of Radiology, The Children`s Hospital of Alabama, Birmingham (United States); Grabb, P.A. [Department of Neurosurgery, University of Alabama at Birmingham (United States)

    1999-04-01

    Objective. To demonstrate the utility of magnetic resonance (MR) imaging in the diagnosis of complete and partial ligamentous injuries in patients with suspected atlanto-occipital dissociation (AOD). Materials and methods. Five patients with suspected AOD had MR imaging performed within an average of 4 days after injury. MR scans were reviewed with specific analysis of craniocervical ligamentous structures. Charts were reviewed to obtain clinical information regarding presentation, treatment, hospital course, and outcome. Results. Two patients demonstrated MR evidence of complete AOD. One had disruption of all visualized major ligamentous structures at the craniocervical junction with anterolisthesis and evidence of cord damage. The second had injuries to the tectorial membrane, superior band of the cruciform ligament, apical ligament, and interspinous ligament at C 1-2. The remaining three patients sustained incomplete severance of the ligamentous structures at the craniocervical junction. All patients demonstrated subtle radiographic findings suggestive of AOD, including soft tissue swelling at the craniocervical junction without fracture. The two patients with complete AOD died. The three patients with partial AOD were treated with stabilization. On follow-up, these three children were asymptomatic following their craniocervical injury. Conclusion. MR imaging of acute AOD provides accurate identification of the craniocervical ligaments injured, classification of full versus partial ligamentous disruption, and analysis of accompanying spinal cord injury. This information is important for early appropriate neurosurgical management and preservation of neurologic function in survivors. (orig.) With 7 figs., 1 tab., 14 refs.

  3. MRI diagnosis of suspected atlanto-occipital dissociation in childhood.

    Science.gov (United States)

    Grabb, B C; Frye, T A; Hedlund, G L; Vaid, Y N; Grabb, P A; Royal, S A

    1999-04-01

    To demonstrate the utility of magnetic resonance (MR) imaging in the diagnosis of complete and partial ligamentous injuries in patients with suspected atlanto-occipital dissociation (AOD). Five patients with suspected AOD had MR imaging performed within an average of 4 days after injury. MR scans were reviewed with specific analysis of craniocervical ligamentous structures. Charts were reviewed to obtain clinical information regarding presentation, treatment, hospital course, and outcome. Two patients demonstrated MR evidence of complete AOD. One had disruption of all visualized major ligamentous structures at the craniocervical junction with anterolisthesis and evidence of cord damage. The second had injuries to the tectorial membrane, superior band of the cruciform ligament, apical ligament, and interspinous ligament at C 1-2. The remaining three patients sustained incomplete severance of the ligamentous structures at the craniocervical junction. All patients demonstrated subtle radiographic findings suggestive of AOD, including soft tissue swelling at the craniocervical junction without fracture. The two patients with complete AOD died. The three patients with partial AOD were treated with stabilization. On follow-up, these three children were asymptomatic following their craniocervical injury. MR imaging of acute AOD provides accurate identification of the craniocervical ligaments injured, classification of full versus partial ligamentous disruption, and analysis of accompanying spinal cord injury. This information is important for early appropriate neurosurgical management and preservation of neurologic function in survivors.

  4. CT Pulmonary Angiography and Suspected Acute Pulmonary Embolism

    Energy Technology Data Exchange (ETDEWEB)

    Enden, T.; Kloew, N.E. [Ullevaal Univ. Hospital, Oslo (Norway). Dept. of Cardiovascular Radiology

    2003-05-01

    Purpose: To evaluate the use and quality of CT pulmonary angiography in our department, and to relate the findings to clinical parameters and diagnoses. Material and Methods: A retrospective study of 324 consecutive patients referred to CT pulmonary angiography with clinically suspected pulmonary embolism (PE). From the medical records we registered clinical parameters, blood gases, D-dimer, risk factors and the results of other relevant imaging studies. Results: 55 patients (17%) had PE detected on CT. 39 had bilateral PE, and 8 patients had isolated peripheral PE. 87% of the examinations showing PE had satisfactory filling of contrast material including the segmental pulmonary arteries, and 60% of the subsegmental arteries. D-dimer test was performed in 209 patients, 85% were positive. A negative D-dimer ruled out PE detected at CT. Dyspnea and concurrent symptoms or detection of deep vein thrombosis (DVT), contraceptive pills and former venous thromboembolism (VTE) were associated with PE. The presence of only one clinical parameter indicated a negative PE diagnosis (p < 0.017), whereas two or more suggested a positive PE diagnosis (p < 0.002). CT also detected various ancillary findings such as consolidation, pleural effusion, nodule or tumor in nearly half of the patients; however, there was no association with the PE diagnosis. Conclusion: The quality of CT pulmonary angiography was satisfactory as a first-line imaging of PE. CT also showed additional pathology of importance in the chest. Our study confirmed that a negative D-dimer ruled out clinically suspected VTE.

  5. Ocular lesions following suspected lightning injury in a horse.

    Science.gov (United States)

    Evans, Paige M; Armour, Micki D; Dubielzig, Richard R

    2012-07-01

      To describe the gross and histopathological ocular findings in a horse following suspected lightning injury.   The eyes of a 2-year-old thoroughbred gelding were clinically and histopathologically evaluated following a severe lightning storm following euthanasia because of visual impairment.   Severe corneal edema and hydrops were noted clinically oculus dexter. Indirect ophthalmoscopy revealed bilateral symmetrical raised hyporeflective peripapillary geographic lesions. Histopathologic evaluation revealed corneal edema in the right eye with normal corneal endothelium. Posterior segment evaluation revealed localized, pericentral choroidal lesions characterized by the presence of hemorrhage, early fibrosis, and minimal lymphoplasmacytic, neutrophilic, and histiocytic inflammation with spindle cell proliferation. The retinas overlying the choroidal lesions were necrotic and mostly absent. Peripheral to the focal lesion, the retina abruptly returned to normal architecture peripheral to a zone of apoptotic photoreceptors. Centrally, swollen axons extended into the optic disc.   There have been few descriptions of ocular lesions in animals following suspected lightning injury. We believe these findings to be unique because of the type of thermal injury that may be characteristic of lightening injury. We do not know whether these lesions would have progressed over time. © 2011 American College of Veterinary Ophthalmologists.

  6. Suspected side effects to the quadrivalent human papilloma vaccine.

    Science.gov (United States)

    Brinth, Louise; Theibel, Ann Cathrine; Pors, Kirsten; Mehlsen, Jesper

    2015-04-01

    The quadrivalent vaccine that protects against human papilloma virus types 6, 11, 16 and 18 (Q-HPV vaccine, Gardasil) was included into the Danish childhood vaccination programme in 2009. During the past years, a collection of symptoms primarily consistent with sympathetic nervous system dysfunction have been described as suspected side effects to the Q-HPV vaccine. We present a description of suspected side effects to the Q-HPV vaccine in 53 patients referred to our Syncope Unit for tilt table test and evaluation of autonomic nervous system function. All patients had symptoms consistent with pronounced autonomic dysfunction including different degrees of orthostatic intolerance, severe non-migraine-like headache, excessive fatigue, cognitive dysfunction, gastrointestinal discomfort and widespread pain of a neuropathic character. We found consistency in the reported symptoms as well as between our findings and those described by others. Our findings neither confirm nor dismiss a causal link to the Q-HPV vaccine, but they suggest that further research is urgently warranted to clarify the pathophysiology behind the symptoms experienced in these patients and to evaluate the possibility and the nature of any causal link and hopefully establish targeted treatment options. not relevant. not relevant.

  7. Patch Testing in Suspected Allergic Contact Dermatitis to Cosmetics

    Science.gov (United States)

    Paulose, Rekha

    2014-01-01

    Background. Increasing use of cosmetics has contributed to a rise in the incidence of allergic contact dermatitis (ACD) to cosmetics. It is estimated that 1–5.4% of the population is sensitized to a cosmetic ingredient. Patch testing helps to confirm the presence of an allergy and to identify the actual allergens which are chemical mixtures of various ingredients. Objectives. The aims of this study are to perform patch testing in suspected ACD to cosmetics and to identify the most common allergen and cosmetic product causing dermatitis. Methods. Fifty patients with suspected ACD to cosmetics were patch-tested with 38 antigens of the Indian Cosmetic Series and 12 antigens of the Indian Standard Series. Results. The majority (58%) of patients belonged to the 21–40 years age group. The presence of ACD to cosmetics was confirmed in 38 (76%) patients. Face creams (20%), hair dyes (14%), and soaps (12%) were the most commonly implicated. The most common allergens identified were gallate mix (40%), cetrimide (28%), and thiomersal (20%). Out of a total of 2531 patches applied, positive reactions were obtained in 3.75%. Conclusion. Incidence of ACD to cosmetics was greater in females. Face creams and hair dyes were the most common cosmetic products implicated. The principal allergens were gallate mix, cetrimide, and thiomersal. PMID:25295057

  8. Feline toxicological emergencies: when to suspect and what to do.

    Science.gov (United States)

    Grave, Tobias W; Boag, Amanda K

    2010-11-01

    Confirmed or suspected intoxications with a wide variety of agents represent a small but important group of feline emergency cases. Generally it is thought that toxicities are less common in cats compared with dogs, with a higher proportion relating to dermal as opposed to oral exposure. Once toxicity is suspected or diagnosed, it must be recognised that treatment regimes may need modification compared with those established for dogs. Different drugs or different dosages may be warranted and the choice of available drugs may be reduced. This review draws on published studies, case reports and clinical experience to summarise key features of the general management of the intoxicated feline patient before describing some of the more serious and common intoxications in more detail. The focus throughout the review is on the peculiarities of feline metabolism and how they may impact on presentation and treatment. The aim is to assist companion animal and feline practitioners, who are in the frontline when it comes to managing these emergency cases. Copyright © 2010 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.

  9. Period changes in ultracompact double white dwarfs

    NARCIS (Netherlands)

    Marsh, T.R.; Nelemans, G.A.

    2005-01-01

    In recent years there has been much interest in the nature of two stars, V407 Vul and RX J0806+1527, which are widely thought to be binary white dwarfs of very short orbital period, 570 and 321s, respectively. As such they should be strong sources of gravitational waves and possible ancestors of the

  10. Influenza Illness among Case-Patients Hospitalized for Suspected Dengue, El Salvador, 2012.

    Directory of Open Access Journals (Sweden)

    Rafael Chacon

    Full Text Available We estimate the proportion of patients hospitalized for suspected dengue that tested positive for influenza virus in El Salvador during the 2012 influenza season. We tested specimens from 321 hospitalized patients: 198 patients with SARI and 123 patients with suspected dengue. Among 121 hospitalized suspected dengue (two co-infected excluded patients, 28% tested positive for dengue and 19% positive for influenza; among 35 with suspected dengue and respiratory symptoms, 14% were positive for dengue and 39% positive for influenza. One percent presented co-infection between influenza and dengue. Clinicians should consider the diagnosis of influenza among patients with suspected dengue during the influenza season.

  11. Influenza Illness among Case-Patients Hospitalized for Suspected Dengue, El Salvador, 2012.

    Science.gov (United States)

    Chacon, Rafael; Clara, Alexey Wilfrido; Jara, Jorge; Armero, Julio; Lozano, Celina; El Omeiri, Nathalie; Widdowson, Marc-Alain; Azziz-Baumgartner, Eduardo

    2015-01-01

    We estimate the proportion of patients hospitalized for suspected dengue that tested positive for influenza virus in El Salvador during the 2012 influenza season. We tested specimens from 321 hospitalized patients: 198 patients with SARI and 123 patients with suspected dengue. Among 121 hospitalized suspected dengue (two co-infected excluded) patients, 28% tested positive for dengue and 19% positive for influenza; among 35 with suspected dengue and respiratory symptoms, 14% were positive for dengue and 39% positive for influenza. One percent presented co-infection between influenza and dengue. Clinicians should consider the diagnosis of influenza among patients with suspected dengue during the influenza season.

  12. Periodic motion near non-principal-axis rotation asteroids

    Science.gov (United States)

    Shang, Haibin; Wu, Xiaoyu; Qin, Xiao; Qiao, Dong

    2017-11-01

    The periodic motion near non-principal-axis (NPA) rotation asteroids is proved to be markedly different from that near uniformly rotating bodies due to the complex spin state with precession, raising challenges in terms of the theoretical implications of dynamical systems. This paper investigates the various periodic motions near the typical NPA asteroid 4179 Toutatis, which will contribute to the understanding of the dynamical environments near the widespread asteroids in the Solar system. A novel method with the incorporation of the ellipsoid-mascon gravitational field model and global optimization is developed to efficiently locate periodic solutions in the system. The numerical results indicate that abundant periodic orbits appear near the NPA asteroids. These various orbits are theoretically classified into five topological types with special attention paid to the cycle stability. Although the concept of classical family disappears in our results, some orbits with the same topological structure constitute various generalized `families' as the period increases. Among these `families' a total of 4 kinds of relationships between orbits, including rotation, evolution, distortion and quasi-symmetry, are found to construct the global mapping of these types. To cover the rotation statuses of various NPA asteroids, this paper also discusses the variation of periodic orbits with diverse asteroid spin rates, showing that the scales of some orbits expand, shrink or almost annihilate as the system period changes; meanwhile, their morphology and topology remain unchanged.

  13. Uterus didelphys with blind hemivagina and ipsilateral renal agenesis (Herlyn-Werner-Wunderlich syndrome) suspected on the presence of hydrocolpos on prenatal sonography.

    Science.gov (United States)

    Han, Byoung Hee; Park, Sung Bin; Lee, Yu Jin; Lee, Kyung Sang; Lee, Yeon Kyung

    2013-01-01

    We report the case of a female neonate with ipsilateral renal agenesis and uterus didelphys with blind hemivagina, also known as Herlyn-Werner-Wunderlich (HWW) syndrome. Prenatal sonography revealed the absence of the left kidney and a retrovesical cystic lesion suspected as hydrometrocolpos. Postnatal evaluation confirmed that the cystic lesion was a hydrocolpos associated with double uterus and blind hemivagina (HWW syndrome). HWW syndrome can be suspected prenatally if a retrovesical cystic lesion is detected in a female fetus with unilateral absence of kidney. Copyright © 2012 Wiley Periodicals, Inc.

  14. Abscess of the orbit arising 48 h after root canal treatment of a maxillary first molar.

    Science.gov (United States)

    Koch, F; Breil, P; Marroquín, B B; Gawehn, J; Kunkel, M

    2006-08-01

    To discuss a rare, but severe complication arising following routine root canal treatment. An orbital abscess is reported that occurred following routine root canal treatment. A young, healthy female patient, with no history of chronic paranasal infection had undergone root canal treatment of the right maxillary first molar. On hospital admission, she presented with extensive periorbital swelling and discreet diplopia. Computed tomography imaging identified massive purulent sinusitis and subsequent involvement of the orbit via the inferior and medial orbital wall within 48 h after completion of root canal treatment. Immediate surgical drainage of the maxillary sinus and the orbit was established and a high dose of perioperative antibiotics (Amoxicillin/Clavulanic acid, Gentamycin, Metronidazole) were administered. Vision remained undisturbed and mobility of the globe recovered within 10 days. Rapid exacerbation of a periapical inflammation may occur following root canal treatment and may even involve the orbit. A typical speed of disease progression or ophthalmic symptoms should alert the clinician to at least consider unusual early orbital spread of odontogenic infection. When extra-alveolar spread and especially orbital spread is suspected, immediate referral to a maxillofacial or other specialized unit is mandatory.

  15. Recognition and management of an orbital blowout fracture in an amateur boxer.

    Science.gov (United States)

    Karsteter, Page A; Yunker, Craig

    2006-08-01

    Case report. To identify key elements in the recognition and management of a patient with an orbital blowout fracture and make recommendations on diagnosis, treatment, referral, imaging, and return to sports. Orbital blowout fractures are uncommon but important injuries for physical therapists to recognize. Immediate management is essential in preventing complications. The mechanism of injury is a direct blow to the orbital rim or orbit. The patient reported to the athletic training room 15 minutes after completing a boxing match and reported that his left eye had suddenly inflated after blowing his nose. We suspected an orbital blowout fracture and referred him immediately to the emergency department where conventional radiographs were ordered. On follow-up the next day, after determining that the radiographs were normal, but still having a high index of suspicion for an orbital blowout fracture, we referred him to his primary care manager. The primary care manager ordered a computed tomography scan that revealed the fracture and referred the patient to ophthalmology. The patient was restricted from the remaining 4 weeks of the boxing season. He completed a rigorous Army physical fitness test 7 days postinjury and the Marine Corps Marathon 47 days postinjury. Orbital blowout fractures without double vision, extraocular muscle entrapment, or persistent numbness can be treated with time and protection. The patient can continue with normal fitness activities except contact or collision sports.

  16. Cosmic Background Explorer (COBE) transfer orbit attitude control system

    Science.gov (United States)

    Placanica, Samuel J.; Flatley, Thomas W.

    1986-01-01

    The Cosmic Background Explorer (COBE) spacecraft will be launched by the Shuttle from Vandenberg AFB into a 300 km altitude, 99 deg inclination, 6 a.m. or 6 p.m. ascending node orbit. After release from the Remote Manipulator System (RMS) arm, an on-board monopropellant hydrazine propulsion system will raise the orbit altitude to 900 km. The spacecraft continuously spins during transfer orbit operations with the spin axis nominally horizontal and in or near the orbit plane. The blowdown propulsion system consists of twelve 5 lb thrusters (3 'spin', 3 'despin', and 6 'axial') with the latter providing initially 30 lb of force parallel to the spin axis for orbit raising. The spin/despin jets provide a constant roll rate during the transfer orbit phase of the mission and the axials control pitch and yaw. The axial thrusters are pulsed on for attitude control during coast periods and are normally on- and off-modulated for control during orbit raising. Attitude sensors employed in the control loops include an array of two-axis digital sun sensors and three planar earth scanners for position measurements, as well as six gyroscopes for rate information. System redundancy is achieved by means of unique three-axes-in-a-plane geometry. This triaxial concept results in a fail-safe operational system with no performance degradation for many different component failure modes.

  17. Evaluation of Improved Spacecraft Models for GLONASS Orbit Determination

    Science.gov (United States)

    Weiss, J. P.; Sibthorpe, A.; Harvey, N.; Bar-Sever, Y.; Kuang, D.

    2010-12-01

    High-fidelity spacecraft models become more important as orbit determination strategies achieve greater levels of precision and accuracy. In this presentation, we assess the impacts of new solar radiation pressure and attitude models on precise orbit determination (POD) for GLONASS spacecraft within JPLs GIPSY-OASIS software. A new solar radiation pressure model is developed by empirically fitting a Fourier expansion to solar pressure forces acting on the spacecraft X, Y, Z components using one year of recent orbit data. Compared to a basic “box-wing” solar pressure model, the median 24-hour orbit prediction accuracy for one month of independent test data improves by 43%. We additionally implement an updated yaw attitude model during eclipse periods. We evaluate the impacts of both models on post-processed POD solutions spanning 6-months. We consider a number of metrics such as internal orbit and clock overlaps as well as comparisons to independent solutions. Improved yaw attitude modeling reduces the dependence of these metrics on the “solar elevation” angle. The updated solar pressure model improves orbit overlap statistics by several mm in the median sense and centimeters in the max sense (1D). Orbit differences relative to the IGS combined solution are at or below the 5 cm level (1D RMS).

  18. Geosynchronous inclined orbits for high-latitude communications

    Science.gov (United States)

    Fantino, E.; Flores, R. M.; Di Carlo, M.; Di Salvo, A.; Cabot, E.

    2017-11-01

    We present and discuss a solution to the growing demand for satellite telecommunication coverage in the high-latitude geographical regions (beyond 55°N), where the signal from geostationary satellites is limited or unavailable. We focus on the dynamical issues associated to the design, the coverage, the maintenance and the disposal of a set of orbits selected for the purpose. Specifically, we identify a group of highly inclined, moderately eccentric geosynchronous orbits derived from the Tundra orbit (geosynchronous, eccentric and critically inclined). Continuous coverage can be guaranteed by a constellation of three satellites in equally spaced planes and suitably phased. By means of a high-precision model of the terrestrial gravity field and the relevant environmental perturbations, we study the evolution of these orbits. The effects of the different perturbations on the ground track (which is more important for coverage than the orbital elements themselves) are isolated and analyzed. The physical model and the numerical setup are optimized with respect to computing time and accuracy. We show that, in order to maintain the ground track unchanged, the key parameters are the orbital period and the argument of perigee. Furthermore, corrections to the right ascension of the ascending node are needed in order to preserve the relative orientation of the orbital planes. A station-keeping strategy that minimizes propellant consumption is then devised, and comparisons are made between the cost of a solution based on impulsive maneuvers and one with continuous thrust. Finally, the issue of end-of-life disposal is discussed.

  19. Self-reported care needs of Dutch homeless people with and without a suspected intellectual disability: a 1.5-year follow-up study.

    Science.gov (United States)

    Van Straaten, Barbara; Rodenburg, Gerda; Van der Laan, Jorien; Boersma, Sandra N; Wolf, Judith R L M; Van de Mheen, Dike

    2017-01-01

    Cognitive impairment is a prevalent problem among the homeless and seems related to more psychosocial problems. However, little is known about the care needs of the subgroup of homeless people with an intellectual disability compared to those without an intellectual disability and how their care needs develop over time. This study explores self-reported care needs within a broad range of life domains among Dutch homeless people with and without a suspected intellectual disability to gain insight into the transition of self-reported care needs from baseline to follow-up in both subgroups. This longitudinal study is part of a cohort study among homeless people who had been accepted for an individual programme plan in four major Dutch cities. The initial cohort consisted of 513 participants who were interviewed in 2011. At 1.5-year follow-up, 336 participants (65.5%) were also interviewed and screened for intellectual disability. Of these participants, 31% (95% CI 26.2-36.1) had a suspected intellectual disability. For both groups, between baseline and follow-up, the number of 'unmet care needs' decreased significantly and the number of 'no care needs' increased significantly, while at follow-up, participants with a suspected intellectual disability reported 'no care needs' on significantly fewer life domains than those without a suspected intellectual disability (mean numbers 16.4 vs. 17.5). Between baseline and follow-up, 'met care needs' decreased significantly on housing for both groups, and increased on finances and dental care for participants with a suspected intellectual disability. At follow-up, participants with a suspected intellectual disability more often preferred housing support available by appointment than those without a suspected intellectual disability. These findings suggest that homeless people who had been accepted for an individual programme plan with a suspected intellectual disability have care needs for a longer period of time than those

  20. Rehabilitation of orbital cavity after orbital exenteration using polymethyl methacrylate orbital prosthesis

    Directory of Open Access Journals (Sweden)

    Sumeet Jain

    2016-01-01

    Full Text Available Squamous cell carcinoma of the eyelid is the second most common malignant neoplasm of the eye with the incidence of 0.09 and 2.42 cases/100 000 people. Orbital invasion is a rare complication but, if recognized early, can be treated effectively with exenteration. Although with advancements in technology such as computer-aided design and computer-aided manufacturing, material science, and retentive methods like implants, orbital prosthesis with stock ocular prosthesis made of methyl methacrylate retained by anatomic undercuts is quiet effective and should not be overlooked and forgotten. This clinical report describes prosthetic rehabilitation of two male patients with polymethyl methacrylate resin orbital prosthesis after orbital exenteration, for squamous cell carcinoma of the upper eyelid. The orbital prosthesis was sufficiently retained by hard and soft tissue undercuts without any complications. The patients using the prosthesis are quite satisfied with the cosmetic results and felt comfortable attending the social events.

  1. Extension of Earth-Moon libration point orbits with solar sail propulsion

    Science.gov (United States)

    Heiligers, Jeannette; Macdonald, Malcolm; Parker, Jeffrey S.

    2016-07-01

    This paper presents families of libration point orbits in the Earth-Moon system that originate from complementing the classical circular restricted three-body problem with a solar sail. Through the use of a differential correction scheme in combination with a continuation on the solar sail induced acceleration, families of Lyapunov, halo, vertical Lyapunov, Earth-centred, and distant retrograde orbits are created. As the solar sail circular restricted three-body problem is non-autonomous, a constraint defined within the differential correction scheme ensures that all orbits are periodic with the Sun's motion around the Earth-Moon system. The continuation method then starts from a classical libration point orbit with a suitable period and increases the solar sail acceleration magnitude to obtain families of orbits that are parametrised by this acceleration. Furthermore, different solar sail steering laws are considered (both in-plane and out-of-plane, and either fixed in the synodic frame or fixed with respect to the direction of Sunlight), adding to the wealth of families of solar sail enabled libration point orbits presented. Finally, the linear stability properties of the generated orbits are investigated to assess the need for active orbital control. It is shown that the solar sail induced acceleration can have a positive effect on the stability of some orbit families, especially those at the L2 point, but that it most often (further) destabilises the orbit. Active control will therefore be needed to ensure long-term survivability of these orbits.

  2. Applying KAM Theory to Highly Eccentric Orbits

    Science.gov (United States)

    2014-03-27

    period of a planet is proportional to the cube of the semi- major axis of its orbit. In 1687, Isaac Newton would prove Kepler’s discoveries after...solving the n-body problem) gave way for more exhaustive research efforts of Newton , Euler, Lagrange, Jacobi, Poincaré, and many others. The King...coordinates, H(I, θ) = H ′(I′), (2.5) 3. Solving the Hamilton-Jacobi equation for the following generating function (Equa- tion (2.6) using a Newton

  3. Orbital cellulitis: review of 23 cases from Saudi Arabia.

    Science.gov (United States)

    Hodges, E; Tabbara, K F

    1989-01-01

    We studied a total of 23 patients with orbital cellulitis and/or orbital abscess over a period of four years in Saudi Arabia. The study showed a high rate of abscess formation (12/23) and surgical intervention (17/23). Twelve out of 23 patients were 18 or more years of age. Furthermore, 12 of 23 (52%) patients had blind eyes on admission and remained blind after treatment, and one patient died of cavernous sinus thrombosis. Only 7/23 (30%) had a predisposing cause of primary sinus disease. This study of orbital cellulitis in a developing country presents a variation in disease pattern from previous reports and suggests that delay in the initiation of antibiotic therapy may lead to serious complications which may be life threatening. The course and outcome of orbital cellulitis may vary, depending on the predisposing factor, time of onset, associated systemic disease, or delay in initiation of treatment. PMID:2706211

  4. Transport orbits in an equilateral restricted four-body problem

    Science.gov (United States)

    Alvarez-Ramírez, M.; Barrabés, E.

    2015-02-01

    In this paper we consider a restricted equilateral four-body problem where a particle of negligible mass is moving under the Newtonian gravitational attraction of three masses (called primaries) which move on circular orbits around their center of masses such that their configuration is always an equilateral triangle (Lagrangian configuration). We consider the case of two bodies of equal masses, which in adimensional units is the parameter of the problem. We study numerically the existence of families of unstable periodic orbits, whose invariant stable and unstable manifolds are responsible for the existence of homoclinic and heteroclinic connections, as well as of transit orbits traveling from and to different regions. We explore, for three different values of the mass parameter, what kind of transits and energy levels exist for which there are orbits with prescribed itineraries visiting the neighborhood of different primaries.

  5. LSST: Comprehensive NEO detection, characterization, and orbits

    Science.gov (United States)

    Ivezic, Zeljko; Jones, Lynne

    2014-11-01

    The Large Synoptic Survey Telescope (LSST) has Solar System mapping as one of its four key scientific design drivers, with emphasis on efficient Near-Earth Object (NEO) and Potentially Hazardous Asteroid (PHA) detection, orbit determination, and characterization. The baseline design satisfies strong constraints on the cadence of observations mandated by PHAs such as closely spaced pairs of observations to link different detections and short exposures to avoid trailing losses. Due to frequent repeat visits LSST will effectively provide its own follow-up to derive orbits for detected moving objects. We will describe detailed modeling of LSST operations, incorporating real historical weather and seeing data from Cerro Pachon in Chile, the LSST site, which shows that LSST using its baseline design cadence could find 90% of the PHAs with diameters larger than 250 m, and 75% of those greater than 140 m within ten years. However, simulations also show that LSST can reach the completeness of 90% of PHAs larger than 140m by optimizing observing cadence andextending the survey lifetime to 12 years. In addition to detecting and determining orbits for these PHAs, LSST will also provide valuable data on their physical characteristics through accurate color and variability measurements, which can be used to determine approximate taxonomical types, better size estimates by constraining albedos, rotation periods, and shape characteristics; thus constraining PHA properties relevant for risk mitigation strategies.

  6. Orbital Infarction due to Sickle Cell Disease without Orbital Pain

    Directory of Open Access Journals (Sweden)

    Cameron L. McBride

    2016-01-01

    Full Text Available Sickle cell disease is a hemoglobinopathy that results in paroxysmal arteriolar occlusion and tissue infarction that can manifest in a plurality of tissues. Rarely, these infarcted crises manifest in the bony orbit. Orbital infarction usually presents with acute onset of periorbital tenderness, swelling, erythema, and pain. Soft tissue swelling can result in proptosis and attenuation of extraocular movements. Expedient diagnosis of sickle cell orbital infarction is crucial because this is a potentially sight-threatening entity. Diagnosis can be delayed since the presentation has physical and radiographic findings mimicking various infectious and traumatic processes. We describe a patient who presented with sickle cell orbital crisis without pain. This case highlights the importance of maintaining a high index of suspicion in patients with known sickle cell disease or of African descent born outside the United States in a region where screening for hemoglobinopathy is not routine, even when the presentation is not classic.

  7. SPHERES Mars Orbiting Sample Return External Orbiting Capture Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's Mars Sample Return (MSR) mission scenario utilizes a small Orbiting Sample (OS) satellite, launched from the surface of Mars, which will rendezvous with an...

  8. Using Internet Artifacts to Profile a Child Pornography Suspect

    Directory of Open Access Journals (Sweden)

    Marcus K. Rogers

    2014-03-01

    Full Text Available Digital evidence plays a crucial role in child pornography investigations. However, in the following case study, the authors argue that the behavioral analysis or “profiling” of digital evidence can also play a vital role in child pornography investigations. The following case study assessed the Internet Browsing History (Internet Explorer Bookmarks, Mozilla Bookmarks, and Mozilla History from a suspected child pornography user’s computer. The suspect in this case claimed to be conducting an ad hoc law enforcement investigation. After the URLs were classified (Neutral; Adult Porn; Child Porn; Adult Dating sites; Pictures from Social Networking Profiles; Chat Sessions; Bestiality; Data Cleaning; Gay Porn, the Internet history files were statistically analyzed to determine prevalence and trends in Internet browsing. First, a frequency analysis was used to determine a baseline of online behavior. Results showed 54% (n = 3205 of the URLs were classified as “neutral” and 38.8% (n = 2265 of the URLs were classified as a porn website. Only 10.8% of the URLs were classified as child pornography websites. However when the IE history file was analyzed by visit, or “hit,” count, the Pictures/Profiles (31.5% category had the highest visit count followed by Neutral (19.3%, Gay Porn (17%, and Child Porn (16.6%. When comparing the frequency of URLs to the Hit Count for each pornography type, it was noted that the accused was accessing gay porn, child porn, chat rooms, and picture profiles (i.e., from Facebook more often than adult porn and neutral websites. The authors concluded that the suspect in this case was in fact a child pornography user and not an ad hoc investigator, and the findings from the behavioral analysis were admitted as evidence in the sentencing hearing for this case. The authors believe this case study illustrates the ability to conduct a behavioral analysis of digital evidence. More work is required to further validate the

  9. Teicoplanin versus vancomycin for proven or suspected infection.

    Science.gov (United States)

    Cavalcanti, Alexandre B; Goncalves, Anderson R; Almeida, Claudia S; Bugano, Diogo Dg; Silva, Eliezer

    2010-06-16

    Vancomycin and teicoplanin are commonly used to treat gram-positive infections, particularly those caused by methicillin-resistant Staphylococcus aureus (MRSA). There is uncertainty regarding the effects of teicoplanin compared to vancomycin on kidney function with some previous studies suggesting teicoplanin is less nephrotoxic than vancomycin. To investigate the efficacy and safety of vancomycin versus teicoplanin in patients with proven or suspected infection. We searched the Cochrane Renal Group's Specialised Register, CENTRAL, MEDLINE, EMBASE, reference lists of nephrology textbooks, review articles with relevant studies and sent letters seeking information about unpublished or incomplete studies to investigators involved in previous studies. We searched for randomised controlled trials (RCTs) in any language comparing teicoplanin to vancomycin for patients with proven or suspected infection. Two authors independently evaluated methodological quality and extracted data using standardised data extraction forms. Study investigators were contacted for information not available in the original manuscripts. Random effects model was used to estimate the pooled risk ratio (RR) with 95% confidence interval (CI). We included 24 studies (2,610 patients) in this review. Teicoplanin reduced the risk of nephrotoxicity compared to vancomycin (RR 0.66, 95% CI 0.48 to 0.90).The effects of teicoplanin or vancomycin were similar for clinical cure (RR 1.03, 95% CI 0.98 to 1.08), microbiological cure (RR 0.98, 95% CI 0.93 to 1.03) and mortality (RR 1.02, 95% CI 0.79 to1.30). Six studies reported no cases of acute kidney injury (AKI) needing dialysis. Adverse events were less frequent with teicoplanin including cutaneous rash (RR 0.57, 95% CI 0.35 to 0.92), red man syndrome (RR 0.21, 95% CI 0.08 to 0.59) and total adverse events (RR 0.73, 95% CI 0.53 to 1.00). A lower risk of nephrotoxicity with teicoplanin was observed in patients either with (RR 0.51, 95% CI 0.30 to 0.88) or

  10. Analysis of Characteristics of QZSS Satellite Orbit and Clock Products during Yaw Attitude Model Switching

    Directory of Open Access Journals (Sweden)

    ZHOU Peiyuan

    2016-03-01

    Full Text Available Yaw attitude model switching of navigation satellites have great impact on its orbit and clock products derived from precise orbit determination. Firstly, the yaw attitude and solar radiation model of QZSS is given briefly. Then, using QZSS precise orbit and clock products provided by IGS MGEX analysis center, precision of orbit and clock is analyzed by satellite laser ranging residuals and polynomial fit residuals respectively. Finally, spectral analysis and modified Allan variance is carried out on clock products to reveal its periodic variations. Research on QZSS satellite orbit and clock products of 2014 shows that there are two eclipse seasons of 20 days and the beta angle is fluctuating with a period of half-year. And there is significant correlation between the precision of orbit and clock products and beta angle. Moreover, the satellite clock offset has periodic variations similar to orbit periods and its amplitude is changing with the beta angle which indicates problems of current orbit determination strategies. In view of similarities between QZSS and BeiDou IGSO and MEO satellites in yaw attitude model, the conclusion is beneficial to improve BeiDou precise orbit determination.

  11. JSC Orbital Debris Website Description

    Science.gov (United States)

    Johnson, Nicholas L.

    2006-01-01

    Purpose: The website provides information about the NASA Orbital Debris Program Office at JSC, which is the lead NASA center for orbital debris research. It is recognized world-wide for its leadership in addressing orbital debris issues. The NASA Orbital Debris Program Office has taken the international lead in conducting measurements of the environment and in developing the technical consensus for adopting mitigation measures to protect users of the orbital environment. Work at the center continues with developing an improved understanding of the orbital debris environment and measures that can be taken to control its growth. Major Contents: Orbital Debris research is divided into the following five broad efforts. Each area of research contains specific information as follows: 1) Modeling - NASA scientists continue to develop and upgrade orbital debris models to describe and characterize the current and future debris environment. Evolutionary and engineering models are described in detail. Downloadable items include a document in PDF format and executable software. 2) Measurements - Measurements of near-Earth orbital debris are accomplished by conducting ground-based and space-based observations of the orbital debris environment. The data from these sources provide validation of the environment models and identify the presence of new sources. Radar, optical and surface examinations are described. External links to related topics are provided. 3) Protection - Orbital debris protection involves conducting hypervelocity impact measurements to assess the risk presented by orbital debris to operating spacecraft and developing new materials and new designs to provide better protection from the environment with less weight penalty. The data from this work provides the link between the environment defined by the models and the risk presented by that environment to operating spacecraft and provides recommendations on design and operations procedures to reduce the risk as

  12. A UNIFIED FRAMEWORK FOR THE ORBITAL STRUCTURE OF BARS AND TRIAXIAL ELLIPSOIDS

    Energy Technology Data Exchange (ETDEWEB)

    Valluri, Monica; Abbott, Caleb [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Shen, Juntai [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China); Debattista, Victor P., E-mail: mvalluri@umich.edu, E-mail: calebga@umich.edu, E-mail: jshen@shao.ac.cn, E-mail: vpdebattista@uclan.ac.uk [Jeremiah Horrocks Institute, University of Central Lancashire, Preston, PR1 2HE (United Kingdom)

    2016-02-20

    We examine a large random sample of orbits in two self-consistent simulations of N-body bars. Orbits in these bars are classified both visually and with a new automated orbit classification method based on frequency analysis. The well-known prograde x1 orbit family originates from the same parent orbit as the box orbits in stationary and rotating triaxial ellipsoids. However, only a small fraction of bar orbits (∼4%) have predominately prograde motion like their periodic parent orbit. Most bar orbits arising from the x1 orbit have little net angular momentum in the bar frame, making them equivalent to box orbits in rotating triaxial potentials. In these simulations a small fraction of bar orbits (∼7%) are long-axis tubes that behave exactly like those in triaxial ellipsoids: they are tipped about the intermediate axis owing to the Coriolis force, with the sense of tipping determined by the sign of their angular momentum about the long axis. No orbits parented by prograde periodic x2 orbits are found in the pure bar model, but a tiny population (∼2%) of short-axis tube orbits parented by retrograde x4 orbits are found. When a central point mass representing a supermassive black hole (SMBH) is grown adiabatically at the center of the bar, those orbits that lie in the immediate vicinity of the SMBH are transformed into precessing Keplerian orbits that belong to the same major families (short-axis tubes, long-axis tubes and boxes) occupying the bar at larger radii. During the growth of an SMBH, the inflow of mass and outward transport of angular momentum transform some x1 and long-axis tube orbits into prograde short-axis tubes. This study has important implications for future attempts to constrain the masses of SMBHs in barred galaxies using orbit-based methods like the Schwarzschild orbit superposition scheme and for understanding the observed features in barred galaxies.

  13. Pararenal splenosis encountered during the evaluation of a suspected pheochromocytoma.

    Science.gov (United States)

    Brown, Joel D; Kwee, Sandi

    2010-11-01

    The authors describe a patient in whom pararenal splenosis nodules were initially interpreted as probable pheochromocytoma. A 22-year-old man with chronic glomerulonephritis, hypertension and a childhood history of splenectomy was hospitalized for a hypertensive emergency. He did not improve with aggressive antihypertensive therapy. A pheochromocytoma was suspected, and a renal ultrasound and a magnetic resonance imaging showed 2 left pararenal masses. Laboratory evaluation for pheochromocytoma and aldosteronoma were negative. Biopsies of the masses were planned, but the masses were subsequently shown to be splenic tissue by a (99m)technnetium heat-damaged red blood cell scan. Ectopic splenic masses, eg, splenosis or accessory spleens, should be considered in patients with undiagnosed abdominal or kidney masses and a history of splenectomy.

  14. Seroprevalance of brucellosis among suspected cases in Malaysia.

    Science.gov (United States)

    Jama'ayah, M Z; Heu, J Y; Norazah, A

    2011-06-01

    Brucellosis is a zoonotic disease which can be transmitted by direct or indirect contact with infected animal or their products. It is an important public health problem but little is known on brucellosis in the Malaysian population. The aim of this study was to determine the presence of Brucella antibodies using commercial Brucella IgG and IgM ELISA kits (Vircell, SL, Barcelona Spain). A total of 184 sera from suspected patients were received from 16 hospitals in Malaysia over the years 2004 to 2009. Only 10 serum samples (5.4%) were positive for Brucella antibodies in which 5 showed the presence of both IgM and IgG. Most of the positive patients were occupationally involved with animals. This study suggests the seroprevalance of brucellosis among individuals who have contact with infected animals in Malaysia is low.

  15. Unenhanced MR Imaging in adults with clinically suspected acute appendicitis

    DEFF Research Database (Denmark)

    Chabanova, Elizaveta; Balslev, Ingegerd; Achiam, Michael

    2011-01-01

    PURPOSE: The purpose of the study was to evaluate unenhanced Magnetic Resonance Imaging (MRI) for the diagnosis of appendicitis or another surgery-requiring condition in an adult population scheduled for emergency appendectomy based on a clinical diagnosis of suspected acute appendicitis. MATERIALS...... radiologists and one surgeon independent of each other and compared with surgical and pathological records. RESULTS: According to the surgical and histopathological findings 30 of 48 patients (63%) had acute appendicitis. Of the remaining 18 patients, 4 patients had no reasons for the clinical symptoms and 14...... patients had other pathology. For the three reviewers the performance of MRI in the diagnosis of acute appendicitis showed the following sensitivity, specificity and accuracy ranges: 83-93%, 50-83% and 77-83%. Moderate (kappa=0.51) and fair (kappa=0.31) interobserver agreements in the MR diagnosis of acute...

  16. CT diagnosis of suspected acute appendicitis in adult patients

    Energy Technology Data Exchange (ETDEWEB)

    Yamase, Hiroshi; Sahashi, Kiyomi; Kawai, Masayuki; Kishida, Yoshihiko; Sumida, Kei; Kawamura, Ken-ichi [Gifu Syakaihoken Hospital (Japan)

    1998-06-01

    In order to assess the CT diagnosis of suspected acute appendicitis, we performed abdominal contrasted CT measurements in 77 patients from 20 to 86 years old, and of 50 men and 27 women from June 1993 to June 1996. The surgical findings were compared with the preoperative CT findings. By the preoperative CT imaging, we can know the degree and the position of inflammation in appendix vermiformis and the degree and the spread of periappendicular inflammation in the case of appendicitis, and can make a differential diagnosis of diverticulitis or gynecological diseases from appendicitis. It is important to make a preoperative diagnosis by the objectively excellent abdominal CT imaging and to avoid unnecessary surgery. (K.H.)

  17. A study of sports-related orbital fractures in Singapore.

    Science.gov (United States)

    Lock, Jing Zhan; Hegde, Raghuraj; Young, Stephanie; Lim, Thiam Chye; Amrith, Shantha; Sundar, Gangadhara

    2017-10-01

    With an increased popularity of sport and active living worldwide, our study aims to explore the incidence and features of sports-related orbital fractures in Singapore. 1421 computer tomography (CT) imaging scans of the face and orbits done at the National University Hospital over a 24-month period from January 2013 and December 2014 were reviewed retrospectively for orbital fractures. We identified 483 orbital fractures of which sports injury was the fourth most common etiology (n = 65; 13.5%) after road traffic accident (n = 131; 27.1%), geriatric fall (n = 81; 16.8%) and workplace injury (n = 67; 13.9%). The three most common sport in orbital fractures were soccer (n = 20; 30.8%), bicycling (n = 11; 16.9%) and jogging (n = 8; 12.3%). The three most common fracture patterns were zygomatico-maxillary complex fractures (n = 24; 36.9%), isolated one wall blowout fractures (n = 19; 29.2%) and naso-orbito-ethmoid fractures (n = 7; 10.8%). Sports-related orbital fractures were associated with a low mean age of patients (45.9 years, range, 14-79 years), a higher proportion of males (n = 58; 89.2%) than that from geriatric falls (n = 37, 45.6%) (P Sports-related orbital fractures are the fourth most common cause of orbital fractures. Though commonly seen in young male adults, in view of the aging population and people exercising more regularly, education of safety measures among sports users is paramount to preventing sports-related orbital fractures.

  18. Reliability of Examination Findings in Suspected Community-Acquired Pneumonia.

    Science.gov (United States)

    Florin, Todd A; Ambroggio, Lilliam; Brokamp, Cole; Rattan, Mantosh S; Crotty, Eric J; Kachelmeyer, Andrea; Ruddy, Richard M; Shah, Samir S

    2017-09-01

    The authors of national guidelines emphasize the use of history and examination findings to diagnose community-acquired pneumonia (CAP) in outpatient children. Little is known about the interrater reliability of the physical examination in children with suspected CAP. This was a prospective cohort study of children with suspected CAP presenting to a pediatric emergency department from July 2013 to May 2016. Children aged 3 months to 18 years with lower respiratory signs or symptoms who received a chest radiograph were included. We excluded children hospitalized ≤14 days before the study visit and those with a chronic medical condition or aspiration. Two clinicians performed independent examinations and completed identical forms reporting examination findings. Interrater reliability for each finding was reported by using Fleiss' kappa (κ) for categorical variables and intraclass correlation coefficient (ICC) for continuous variables. No examination finding had substantial agreement (κ/ICC > 0.8). Two findings (retractions, wheezing) had moderate to substantial agreement (κ/ICC = 0.6-0.8). Nine findings (abdominal pain, pleuritic pain, nasal flaring, skin color, overall impression, cool extremities, tachypnea, respiratory rate, and crackles/rales) had fair to moderate agreement (κ/ICC = 0.4-0.6). Eight findings (capillary refill time, cough, rhonchi, head bobbing, behavior, grunting, general appearance, and decreased breath sounds) had poor to fair reliability (κ/ICC = 0-0.4). Only 3 examination findings had acceptable agreement, with the lower 95% confidence limit >0.4: wheezing, retractions, and respiratory rate. In this study, we found fair to moderate reliability of many findings used to diagnose CAP. Only 3 findings had acceptable levels of reliability. These findings must be considered in the clinical management and research of pediatric CAP. Copyright © 2017 by the American Academy of Pediatrics.

  19. Investigating suspected acute pulmonary embolism - what are hospital clinicians thinking?

    Energy Technology Data Exchange (ETDEWEB)

    McQueen, A.S. [Department of Radiology, Royal Victoria Infirmary, Newcastle upon Tyne (United Kingdom)], E-mail: andrewmcqueen7@hotmail.com; Worthy, S. [Department of Radiology, Royal Victoria Infirmary, Newcastle upon Tyne (United Kingdom); Keir, M.J. [Department of Medical Physics, Royal Victoria Infirmary, Newcastle upon Tyne (United Kingdom)

    2008-06-15

    Aims: To assess local clinical knowledge of the appropriate investigation of suspected acute pulmonary embolism (PE) and this compare with the 2003 British Thoracic Society (BTS) guidelines as a national reference standard. Methods: A clinical questionnaire was produced based on the BTS guidelines. One hundred and eight-six participants completed the questionnaires at educational sessions for clinicians of all grades, within a single NHS Trust. The level of experience amongst participants ranged from final year medical students to consultant physicians. Results: The clinicians were divided into four groups based on seniority: Pre-registration, Junior, Middle, and Senior. Forty-six point eight percent of all the clinicians correctly identified three major risk factors for PE and 25.8% recognized the definition of the recommended clinical probability score from two alternatives. Statements regarding the sensitivity of isotope lung imaging and computed tomography pulmonary angiography (CTPA) received correct responses from 41.4 and 43% of participants, respectively, whilst 81.2% recognized that an indeterminate ventilation-perfusion scintigraphy (V/Q) study requires further imaging. The majority of clinicians correctly answered three clinical scenario questions regarding use of D-dimers and imaging (78, 85, and 57.5%). There was no statistically significant difference between the four groups for any of the eight questions. Conclusions: The recommended clinical probability score was unfamiliar to all four groups of clinicians in the present study, and the majority of doctors did not agree that a negative CTPA or isotope lung scintigraphy reliably excluded PE. However, questions based on clinical scenarios received considerably higher rates of correct responses. The results indicate that various aspects of the national guidelines on suspected acute pulmonary embolism are unfamiliar to many UK hospital clinicians. Further research is needed to identify methods to improve

  20. Direct access exercise electrocardiography: a new service that improves the management of suspected ischaemic heart disease in the community.

    Science.gov (United States)

    McClements, B. M.; Campbell, N. P.; Cochrane, D.; Stockman, S.

    1994-01-01

    OBJECTIVE--To assess the safety and value of an exercise electrocardiography service for the diagnosis of suspected ischaemic heart disease to which general practitioners have direct access. DESIGN--Direct access to a hospital exercise electrocardiography service was offered on a trial basis to 122 general practitioners in a defined urban area. Maximal exercise tests were performed according to the modified Bruce protocol and the results were dispatched promptly to the referring doctors who were responsible for the subsequent management of their patients. SETTING--All general practices in north and west Belfast (combined list size about 180,000) and the regional medical cardiology centre. PATIENTS--212 request forms were received in a two year period and 192 eligible patients attended for exercise testing. All patients were suspected to have pain due to myocardial ischaemia, were aged electrocardiography for patients with suspected ischaemic heart disease is safe, feasible, and helpful to general practitioners. This service seems to reduce the number of patients referred to cardiology outpatient clinics and to facilitate the management of these patients in the community. PMID:8043332

  1. Magnetic resonance venography in consecutive patients with suspected deep vein thrombosis of the upper extremity: initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Baarslag, H.J.; Reekers, J.A. [Academic Medical Centre, Amsterdam (Netherlands). Dept. of Radiology; Beek, E.J. van [Royal Hallamshire Hospital, Sheffield (United Kingdom). Unit of Academic Radiology

    2004-02-01

    To assess the feasibility and accuracy of two magnetic resonance (MR) venography methods in a consecutive series of patients with suspected deep vein thrombosis of the upper extremity (DVTUE). Consecutive in- and outpatients who were referred for imaging of suspected DVTUE in a large teaching hospital during the period April 2001 to October 2002 were eligible for inclusion. All patients were scheduled to undergo contrast venography with the intention to perform additional MR venography. Both time-of-flight and gadolinium-enhanced 3D MR venography were scheduled. All MR imaging were interpreted independently by consensus of two experienced radiologists, who were blinded for contrast venography outcome. Patients were managed based on contrast venography only. A total of 44 patients were eligible for inclusion. Thirteen patients were excluded (5 refused consent, 2 inability to gain venous access, 2 renal failure, 4 logistic reasons). Contrast venography was performed in 31 patients, and demonstrated DVTUE in 11 patients. MR imaging was not feasible in 10 patients (4 unable to lie flat, 3 claustrophobia, 1 too large for MR scanner, 1 osteosynthesis of shoulder, 1 pacemaker). The sensitivity and specificity of TOF MRV versus Gadolinium 3D MRV was 71% and 89% versus 50% and 80%, respectively. A high number of patients were unable to undergo MR venography in this setting. Contrast-enhanced MRV did not improve diagnostic accuracy. The clinical utility of MR venography in the setting of suspected DVTUE seems disappointing.

  2. High Power Orbit Transfer Vehicle

    National Research Council Canada - National Science Library

    Gulczinski, Frank

    2003-01-01

    ... from Virginia Tech University and Aerophysics, Inc. to examine propulsion requirements for a high-power orbit transfer vehicle using thin-film voltaic solar array technologies under development by the Space Vehicles Directorate (dubbed PowerSail...

  3. Management of odontogenic orbital cellulitis.

    Science.gov (United States)

    DeCroos, F C; Liao, J C; Ramey, N A; Li, I

    2011-08-15

    This work describes a series of patients with odontogenic orbital cellulitis (OOC), focusing on rate of abscess formation, need for surgical intervention, and imaging findings helpful for rapid diagnosis. Review of a current case and 22 patients with OOC from the scientific literature demonstrated periapical lucency as the most commonly (36.4%) reported finding on facial and orbital computerized tomography (CT) scan. Orbital abscess occurred in 72.7% of cases, and tooth extraction and/or abscess drainage was required in 95.5% of cases reviewed for control of infection. The current case presented with periapical lucency on CT scan, developed orbital abscess despite broad spectrum antibiotic therapy, and required multiple surgical interventions for disease resolution. Though our patient regained excellent vision, OOC often can result in severe vision loss. Periapical lucency on CT can help identify this atypical origin of cellulitis that is strongly associated with abscess formation and need for surgical intervention.

  4. Search for Orbital Motion of the Pulsar 4U 1626-67: Candidate for a ...

    Indian Academy of Sciences (India)

    periodic signal with the desired resolution in orbital period. ... same figure, sections of the light curve are shown with a time resolution of 0.125 s and .... 181. Figure 4. Upper limit of ax sin(i) (in lt-ms) for different trial orbital periods. The top panel shows the 1σ upper limit ofax sin(i)while the bottom panel shows the 3σ upper ...

  5. Uncertainty Requirement Analysis for the Orbit, Attitude, and Burn Performance of the 1st Lunar Orbit Insertion Maneuver

    Science.gov (United States)

    Song, Young-Joo; Bae, Jonghee; Kim, Young-Rok; Kim, Bang-Yeop

    2016-12-01

    In this study, the uncertainty requirements for orbit, attitude, and burn performance were estimated and analyzed for the execution of the 1st lunar orbit insertion (LOI) maneuver of the Korea Pathfinder Lunar Orbiter (KPLO) mission. During the early design phase of the system, associate analysis is an essential design factor as the 1st LOI maneuver is the largest burn that utilizes the onboard propulsion system; the success of the lunar capture is directly affected by the performance achieved. For the analysis, the spacecraft is assumed to have already approached the periselene with a hyperbolic arrival trajectory around the moon. In addition, diverse arrival conditions and mission constraints were considered, such as varying periselene approach velocity, altitude, and orbital period of the capture orbit after execution of the 1st LOI maneuver. The current analysis assumed an impulsive LOI maneuver, and two-body equations of motion were adapted to simplify the problem for a preliminary analysis. Monte Carlo simulations were performed for the statistical analysis to analyze diverse uncertainties that might arise at the moment when the maneuver is executed. As a result, three major requirements were analyzed and estimated for the early design phase. First, the minimum requirements were estimated for the burn performance to be captured around the moon. Second, the requirements for orbit, attitude, and maneuver burn performances were simultaneously estimated and analyzed to maintain the 1st elliptical orbit achieved around the moon within the specified orbital period. Finally, the dispersion requirements on the B-plane aiming at target points to meet the target insertion goal were analyzed and can be utilized as reference target guidelines for a mid-course correction (MCC) maneuver during the transfer. More detailed system requirements for the KPLO mission, particularly for the spacecraft bus itself and for the flight dynamics subsystem at the ground control center

  6. Uncertainty Requirement Analysis for the Orbit, Attitude, and Burn Performance of the 1st Lunar Orbit Insertion Maneuver

    Directory of Open Access Journals (Sweden)

    Young-Joo Song

    2016-12-01

    Full Text Available In this study, the uncertainty requirements for orbit, attitude, and burn performance were estimated and analyzed for the execution of the 1st lunar orbit insertion (LOI maneuver of the Korea Pathfinder Lunar Orbiter (KPLO mission. During the early design phase of the system, associate analysis is an essential design factor as the 1st LOI maneuver is the largest burn that utilizes the onboard propulsion system; the success of the lunar capture is directly affected by the performance achieved. For the analysis, the spacecraft is assumed to have already approached the periselene with a hyperbolic arrival trajectory around the moon. In addition, diverse arrival conditions and mission constraints were considered, such as varying periselene approach velocity, altitude, and orbital period of the capture orbit after execution of the 1st LOI maneuver. The current analysis assumed an impulsive LOI maneuver, and two-body equations of motion were adapted to simplify the problem for a preliminary analysis. Monte Carlo simulations were performed for the statistical analysis to analyze diverse uncertainties that might arise at the moment when the maneuver is executed. As a result, three major requirements were analyzed and estimated for the early design phase. First, the minimum requirements were estimated for the burn performance to be captured around the moon. Second, the requirements for orbit, attitude, and maneuver burn performances were simultaneously estimated and analyzed to maintain the 1st elliptical orbit achieved around the moon within the specified orbital period. Finally, the dispersion requirements on the B-plane aiming at target points to meet the target insertion goal were analyzed and can be utilized as reference target guidelines for a mid-course correction (MCC maneuver during the transfer. More detailed system requirements for the KPLO mission, particularly for the spacecraft bus itself and for the flight dynamics subsystem at the ground

  7. Birth of resonances in the spin-orbit problem of Celestial Mechanics

    CERN Document Server

    Celletti, A; Celletti, Alessandra; Chierchia, Luigi

    1999-01-01

    The behaviour of resonances in the spin-orbit coupling in Celestial Mechanics is investigated. We introduce a Hamiltonian nearly-integrable model describing an approximation of the spin-orbit interaction. A parametric representation of periodic orbits is presented. We provide explicit formulae to compute the Taylor series expansion in the perturbing parameter of the function describing this parametrization. Then we compute approximately the radius of convergence providing an indication of the stability of the periodic orbit. This quantity is used to describe the different probabilities of capture into resonance. In particular, we notice that for low values of the orbital eccentricity the only significative resonance is the synchronous one. Higher order resonances (including 1:2, 3:2, 2:1) appear only as the orbital eccentricity is increased.

  8. Orbital operations study. Executive summary

    Science.gov (United States)

    Hogan, L. R.

    1972-01-01

    A summary of the analyses of the orbital operations study is presented. Objectives, scope of study, and technical documentation format are discussed. A summary of the mission analyses including generic mission models, element pair interactions, and interfacing activities are presented. The analyses associated with each interfacing activity are also summarized. Significant implications derived during the course of the study on the EOS orbiter, space tug, RAM, and MSS are indicated.

  9. Families of asymmetric periodic solutions in the restricted four-body problem

    Science.gov (United States)

    Papadakis, K. E.

    2016-12-01

    Very recently, we presented five of the basic families of the network of periodic orbits of the restricted four-body problem which are simple, i.e. one intersection with the horizontal x-axis at the half period, symmetric with respect to the same axis and asymmetric with respect to the vertical y-axis. In the present work, using these families, we found series of asymmetric critical orbits for various values of the primaries m2 and m3. From these critical orbits we calculate and present five new families of simple periodic orbits which are asymmetric with respect to both the x- and y-axis. Additionally, we describe a grid method in the (x0, dot{x}0) plane and we obtain initial conditions for new asymmetric double-periodic orbits. We determine ten families of asymmetric double-periodic orbits from the bifurcations of the previous five asymmetric families using the special generating horizontally critical periodic orbits. The stability of each calculated asymmetric periodic orbit is also studied. Characteristic curves as well as stability diagrams of these families are illustrated. In the last section we present the evolution of the five basic families of simple asymmetric periodic orbits when the primaries are the Sun the Jupiter and the 2797 Teucer Asteroid.

  10. Clinical value of FDG-PET/CT in suspected paraneoplastic syndromes: a retrospective analysis of 137 patients

    Energy Technology Data Exchange (ETDEWEB)

    Bjoern Kristensen, Stine; Hess, Soeren; Petersen, Henrik; Hoeilund-Carlsen, Poul Flemming [Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark)

    2015-12-15

    Paraneoplastic syndromes (PNS) are relatively infrequent manifestations appearing before or after a cancer declares itself. Autoimmune mechanisms may be involved, but their cause and pathogenesis are often unknown. Due to disparity of symptoms, PNS remain a major diagnostic challenge. We examined the value of FDG-PET/CT for ruling in or out malignancy in a heterogeneous group of patients with suspected PNS. We retrospectively extracted data from all patients referred 2009-2013 with suspected PNS. Data included age, sex, follow-up period, scan report, further diagnostic procedures, and final clinical diagnosis. Conclusions of the scan reports were compared to the final follow-up outcome as determined during an average follow-up of 31 months (range 6-51.5) in patients who were not diagnosed with cancer in immediate continuation of a positive PET/CT scan. A total of 137 patients were included. Main causes for referral were neurological (n = 67), rheumatological (n = 25), dermatological (n = 18), nephrological (n = 6), haematological (n = 2), abnormal biochemistry (n = 11), and others (n = 8). The cancer prevalence was 8.8 %. The FDG-PET/CT results were as follows: nine true positives, 22 false positives, 103 true negatives, and three false negatives. Corresponding diagnostic values were: sensitivity 75 %, specificity 82 %, accuracy 82 %, and positive and negative predictive values of 29 % and 97 %, respectively. FDG-PET/CT has in patients with suspected PNS an impressively high negative predictive value and may be of value in ruling out PNS, the more so, the more the number of false positives can be minimized or used in differential diagnosis. We believe that FDG-PET/CT may become an important adjunct to the work-up and triage of patients with suspected PNS. (orig.)

  11. Microbiological profile of orbital abscess

    Directory of Open Access Journals (Sweden)

    N Suneetha

    2012-01-01

    Full Text Available Background: Knowledge of the culture and sensitivity pattern is necessary, for the institution of appropriate empirical antibiotic therapy in orbital abscess. Objective: The objective of this study is to describe culture and sensitivity patterns of specimens from the orbit and surrounding structures. Materials and Methods: Retrospectively the medical records of 56 cases of orbital abscess were reviewed. Results: Cultures were positive in 38/56 (68.8% orbital specimens and the organisms included Staphylococcus aureus 18, Streptococci 7, Pseudomonas aeruginosa 3, 2 each of Enterobactersp, Escherichia coli, Proteus mirabilis, Acinetobacter sp. and 1 each of Actinomyces israelii, Diptheroids, Coagulase negative Staphylococcus, Citrobacter freundii, Methicillin-resistant S. aureus and Enterococcus faecalis. Four had polymicrobial infection. Culture of purulent nasal discharge, swabs taken from foci of infection on the face, and blood cultures were done in 26/56, and positive cultures were obtained in 16/26 (61.5% specimens. In 12 patients, there was a concurrence in the organism cultured from the orbit and from cultures from other sites. Gram-negative organisms were associated with increased ocular morbidity. Conclusion: Gram-positive cocci, especially S. aureus are the most common organisms isolated from orbital abscesses. Infections by Gram-negative organisms were associated with more complications. Empirical intravenous antibiotic therapy should have a broad spectrum of activity effective against a wide range of Staphylococcal organisms and Gram-negative bacilli.

  12. Double-read of skeletal surveys in suspected non-accidental trauma: what we learned

    Energy Technology Data Exchange (ETDEWEB)

    Karmazyn, Boaz; Wanner, Matthew R.; Marine, Megan B. [Indiana University School of Medicine, Department of Radiology and Imaging Sciences, Riley Hospital for Children, Indianapolis, IN (United States); Miller, Elise M.; Jennings, S.G. [Indiana University School of Medicine, Department of Radiology and Imaging Sciences, Indianapolis, IN (United States); Lay, Sara E. [Indiana University School of Medicine, Methodist Hospital, Department of Radiology and Imaging Sciences, Indianapolis, IN (United States); Massey, James M. [The Children' s Hospital at TriStar Centennial, Department of Imaging, Nashville, TN (United States); Ouyang, Fangqian [Indiana University School of Medicine, Department of Biostatistics, Indianapolis, IN (United States); Hibbard, Roberta A. [Indiana University School of Medicine, Department of Pediatrics, Section of Child Protection Programs, Riley Hospital for Children, Indianapolis, IN (United States)

    2017-05-15

    Missing a fracture in a child on skeletal surveys for suspected non-accidental trauma can have devastating results. Double-read has the potential to improve fracture detection. However the yield of double-read is unknown. To determine the advantage of double-read versus single-read of radiographic skeletal surveys for suspected non-accidental trauma. The study was performed in two phases. In the first phase (April 2013 to September 2013), double-read was performed for all skeletal surveys obtained during weekday working hours. Because we had no new double-read findings in studies initially read as negative, we conducted a second phase (January 2014 to March 2014). In the second phase we limited double-reads to skeletal surveys found positive on the first read. At the end of this period, we retrospectively performed double-read for all initially negative skeletal surveys. We excluded follow-up skeletal surveys. The difference in discrepancy (new fracture or false diagnosis of a fracture) ratio between negative and positive skeletal surveys was evaluated using the Fisher exact test, and change in discrepancy ratio between the first and second study phases was evaluated using the stratified Cochran-Mantel-Haenszel test. Overall in the two phases, 178 skeletal surveys were performed in 178 children (67 girls) with mean age of 9 months (range 3 days to 3.7 years). Double-read found 16 discrepancies in 8/178 (4.5%) skeletal surveys. Seven of these studies showed additional fractures (n=15). In one study, an initial read of a skull fracture was read as a variant on the second read. There was a significant (P=0.01) difference between rate of disagreement in negative skeletal surveys (1/104, 1.0%) and positive skeletal surveys (7/74, 9.5%). No significant change in disagreement rate was demonstrated between the two phases of the study (P=0.59). Double-read of skeletal survey for suspected non-accidental trauma found false-negative fractures in a few cases and rarely found

  13. Progressive lesions of central nervous system in microcephalic fetuses with suspected congenital Zika virus syndrome.

    Science.gov (United States)

    Sarno, M; Aquino, M; Pimentel, K; Cabral, R; Costa, G; Bastos, F; Brites, C

    2017-12-01

    To describe the pattern and progression of central nervous system (CNS) lesions in microcephalic fetuses with suspected Zika virus (ZIKV) infection. In this prospective study in Salvador, Brazil, we analyzed fetuses diagnosed with microcephaly and suspected ZIKV infection after a routine primary care ultrasound scan between July 2015 and February 2016 raised suspicion of fetal microcephaly. The pregnancies were followed with serial ultrasound scans until delivery at one of the three main referral centers for fetal abnormalities in Salvador, Brazil. Microcephaly was diagnosed when the head circumference was two or more SDs below the mean for gestational age and its relationship with ZIKV infection was defined according to the World Health Organization's criteria. All women were interviewed, to assess potential factors associated with fetal microcephaly. Serology test results for toxoplasmosis, cytomegalovirus, rubella, syphilis and human immunodeficiency virus (HIV) were recorded, as were previous routine ultrasound results. Signs/symptoms of infection during the pregnancy were noted. Of 60 cases of suspected ZIKV-related fetal microcephaly seen during the study period, eight were excluded due to serological evidence of other congenital infections or major ultrasound chromosomal markers. In the remaining 52 fetuses, microcephaly was diagnosed between 19 and 40 (median, 27.7; interquartile range, 23.4-32.0) weeks of gestation. The main ultrasound findings were: ventriculomegaly (65.4% of cases), cerebral calcifications (44.2%) and posterior fossa abnormalities (32.7%). 9.6% presented with arthrogryposis as an associated finding. Microcephaly was an isolated finding in four cases (7.7%). While ventriculomegaly was progressive in 41.2% of cases with this finding, the velocity of head circumference increase decreased progressively in almost all cases. Exanthematic disease was present in the majority (86.5%) of the women, 67.3% presenting in the first trimester of

  14. Genotype MTBDR plus (Hain) test in suspected MDR-TB patients.

    Science.gov (United States)

    Sangsayunh, Piamlarp; Chuchothawon, Chareon

    2014-10-01

    correlation between judgments of physician and pattern (default/relapse/failure) ofprevious TB treatment history (p = 0.6), and periods oftime from first diagnosis of TB to develop suspected MDR-TB (p = 0.09) were demonstrated. We recommend Hain test to diagnose MDR-TB in highly suspected cases, and to wait for conventional culture results to confirm NTM. Hain test has benefit in negative direct smear

  15. Absent menstrual periods - primary

    Science.gov (United States)

    Primary amenorrhea; No periods - primary; Absent periods - primary; Absent menses - primary; Absence of periods - primary ... nutrition Tumors In many cases, the cause of primary amenorrhea is not known.

  16. Orbital Eccentricity and the Stability of Planets in the Alpha Centauri System

    Science.gov (United States)

    Lissauer, Jack

    2016-01-01

    Planets on initially circular orbits are typically more dynamically stable than planets initially having nonzero eccentricities. However, the presence of a major perturber that forces periodic oscillations of planetary eccentricity can alter this situation. We investigate the dependance of system lifetime on initial eccentricity for planets orbiting one star within the alpha Centauri system. Our results show that initial conditions chosen to minimize free eccentricity can substantially increase stability compared to planets on circular orbits.

  17. Neurological signs in 23 dogs with suspected rostral cerebellar ischaemic stroke.

    Science.gov (United States)

    Thomsen, Barbara; Garosi, Laurent; Skerritt, Geoff; Rusbridge, Clare; Sparrow, Tim; Berendt, Mette; Gredal, Hanne

    2016-06-07

    In dogs with ischaemic stroke, a very common site of infarction is the cerebellum. The aim of this study was to characterise neurological signs in relation to infarct topography in dogs with suspected cerebellar ischaemic stroke and to report short-term outcome confined to the hospitalisation period. A retrospective multicentre study of dogs with suspected cerebellar ischaemic stroke examined from 2010-2015 at five veterinary referral hospitals was performed. Findings from clinical, neurological, and paraclinical investigations including magnetic resonance imaging were assessed. Twenty-three dogs, 13 females and 10 males with a median age of 8 years and 8 months, were included in the study. The Cavalier King Charles Spaniel (n = 9) was a commonly represented breed. All ischaemic strokes were located to the vascular territory of the rostral cerebellar artery including four extensive and 19 limited occlusions. The most prominent neurological deficits were gait abnormalities (ataxia with hypermetria n = 11, ataxia without hypermetria n = 4, non-ambulatory n = 6), head tilt (n = 13), nystagmus (n = 8), decreased menace response (n = 7), postural reaction deficits (n = 7), and proprioceptive deficits (n = 5). Neurological signs appeared irrespective of the infarct being classified as extensive or limited. All dogs survived and were discharged within 1-10 days of hospitalisation. Dogs affected by rostral cerebellar ischaemic stroke typically present with a collection of neurological deficits characterised by ataxia, head tilt, and nystagmus irrespective of the specific cerebellar infarct topography. In dogs with peracute to acute onset of these neurological deficits, cerebellar ischaemic stroke should be considered an important differential diagnosis, and neuroimaging investigations are indicated. Although dogs are often severely compromised at presentation, short-term prognosis is excellent and rapid clinical improvement may be observed within the

  18. Space Tourism: Orbital Debris Considerations

    Science.gov (United States)

    Mahmoudian, N.; Shajiee, S.; Moghani, T.; Bahrami, M.

    2002-01-01

    Space activities after a phase of research and development, political competition and national prestige have entered an era of real commercialization. Remote sensing, earth observation, and communication are among the areas in which this growing industry is facing competition and declining government money. A project like International Space Station, which draws from public money, has not only opened a window of real multinational cooperation, but also changed space travel from a mere fantasy into a real world activity. Besides research activities for sending man to moon and Mars and other outer planets, space travel has attracted a considerable attention in recent years in the form of space tourism. Four countries from space fairing nations are actively involved in the development of space tourism. Even, nations which are either in early stages of space technology development or just beginning their space activities, have high ambitions in this area. This is worth noting considering their limited resources. At present, trips to space are available, but limited and expensive. To move beyond this point to generally available trips to orbit and week long stays in LEO, in orbital hotels, some of the required basic transportations, living requirements, and technological developments required for long stay in orbit are already underway. For tourism to develop to a real everyday business, not only the price has to come down to meaningful levels, but also safety considerations should be fully developed to attract travelers' trust. A serious hazard to space activities in general and space tourism in particular is space debris in earth orbit. Orbiting debris are man-made objects left over by space operations, hazardous to space missions. Since the higher density of debris population occurs in low earth orbit, which is also the same orbit of interest to space tourism, a careful attention should be paid to the effect of debris on tourism activities. In this study, after a

  19. Triple Difference Approach to Low Earth Orbiter Precision Orbit Determination

    Science.gov (United States)

    Kwon, Jay-Hyoun; Grejner-Brzezinska, Dorota A.; Yom, Jae-Hong; Cheon, Lee-Dong

    2003-03-01

    A precise kinematic orbit determination (P-KOD) procedure for Low Earth Orbiter(LEO) using the GPS ion-free triple differenced carrier phases is presented. Because the triple differenced observables provide only relative information, the first epoch's positions of the orbit should be held fixed. Then, both forward and backward filtering was executed to mitigate the effect of biases of the first epoch's position. P-KOD utilizes the precise GPS orbits and ground stations data from International GPS Service (IGS) so that the only unknown parameters to be solved are positions of the satellite at each epoch. Currently, the 3-D accuracy of P-KOD applied to CHAMP (CHAllenging Minisatellite Payload) shows better than 35 cm compared to the published rapid scientific orbit (RSO) solution from GFZ (GeoForschungsZentrum Potsdam). The data screening for cycle slips is a particularly challenging procedure for LEO, which moves very fast in the middle of the ionospheric layer. It was found that data screening using SNR (signal to noise ratio) generates best results based on the residual analysis using RSO. It is expected that much better accuracy are achievable with refined prescreening procedure and optimized geometry of the satellites and ground stations.

  20. Orbital, subconjunctival, and subcutaneous emphysema after an orbital floor fracture

    Directory of Open Access Journals (Sweden)

    Ababneh OH

    2013-06-01

    Full Text Available Osama H Ababneh Department of Ophthalmology, The University of Jordan and Jordan University Hospital, Amman, Jordan Abstract: A 16-year-old boy presented to the emergency department with the complaint of a sudden, painful left eye and proptosis after an episode of sneezing. A few hours earlier, he had sustained a blunt trauma to the left orbit as the result of a fistfight. The initial examination showed subcutaneous and subconjunctival emphysema. Visual acuity in the left eye was 20/30 (0.67, the pupils were reactive with no relative afferent pupillary defect, and there were mild limitations in levoduction and supraduction. A slit-lamp examination showed normal anterior and posterior segments with an intraocular pressure of 26 mmHg. An orbital computed tomography scan showed orbital, subconjunctival, and subcutaneous emphysema associated with a small fracture of the orbital floor. Following conservative management with broad-spectrum oral antibiotics, a topical antiglaucoma drug, and lubricating eye drops, the patient improved dramatically within one week. Keywords: emphysema, orbital fracture, trauma

  1. Orbital Battleship: A Guessing Game to Reinforce Atomic Structure

    Science.gov (United States)

    Kurushkin, Mikhail; Mikhaylenko, Maria

    2016-01-01

    A competitive educational guessing game "Orbital Battleship" which reinforces Madelung's and Hund's rules, values of quantum numbers, and understanding of periodicity was designed. The game develops strategic thinking, is not time-consuming, requires minimal preparation and supervision, and is an efficient and fun alternative to more…

  2. Solar sail orbital motion about asteriods and binary asteroid systems

    NARCIS (Netherlands)

    Heiligers, M.J.; Scheeres, Daniel J.; Sims, J.A.; Leve, F.A.; McMahon, J.W.; Guo, Y.

    2017-01-01

    While SRP is often considered an undesirable effect, especially for missions to small bodies like asteroids and binary asteroid systems, this paper utilizes the SRP on a solar sail to generate artificial equilibrium points (AEPs) and displaced periodic orbits in these systems. While the solar sail

  3. Congenital orbital teratoma: a case report and challenges of its ...

    African Journals Online (AJOL)

    We report a case of congenital immature teratoma of the orbit in a female neonate who presented on the second day of life. She was successfully managed by modified exenteration. The patient was lost to follow-up intermittently over a 24-month period without recurrence of the tumour. However the patient could not be ...

  4. Gravitational Radiation Damping and Evolution of the Orbit of ...

    Indian Academy of Sciences (India)

    Abstract. The influence of the gravitational radiation damping on the evolution of the orbital elements of compact binary stars is examined by using the method of perturbation. The perturbation equations with the true anomaly as an independent variable are given. This effect results in both the secular and periodic variation ...

  5. Gravitational Radiation Damping and Evolution of the Orbit of ...

    Indian Academy of Sciences (India)

    The influence of the gravitational radiation damping on the evolution of the orbital elements of compact binary stars is examined by using the method of perturbation. The perturbation equations with the true anomaly as an independent variable are given. This effect results in both the secular and periodic variation of the ...

  6. Observations of Geographically Correlated Orbit Errors of TOPEX/POSEIDON

    Science.gov (United States)

    Christensen, E. J.; Haines, B. J.; McColl, K. C.

    1993-01-01

    We have compared GPS-based dynamic and reduced-dynamic TOPEX/POSEIDON orbits over a 10 day period beginning March 10,1993. The results suggest that the prelaunch gravity model (JGM-1) introduces geographically correlated errors which, when projectd on a mean sea survase, have a storng meridional dependence.

  7. Pre-admission antibiotics for suspected cases of meningococcal disease.

    Science.gov (United States)

    Sudarsanam, Thambu D; Rupali, Priscilla; Tharyan, Prathap; Abraham, Ooriapadickal Cherian; Thomas, Kurien

    2013-08-02

    Meningococcal disease can lead to death or disability within hours after onset. Pre-admission antibiotics aim to reduce the risk of serious disease and death by preventing delays in starting therapy before confirmation of the diagnosis. To study the effectiveness and safety of pre-admission antibiotics versus no pre-admission antibiotics or placebo, and different pre-admission antibiotic regimens in decreasing mortality, clinical failure and morbidity in people suspected of meningococcal disease. We updated searches of CENTRAL (2013, Issue 4), MEDLINE (1966 to April week 4, 2013), EMBASE (1980 to May 2013), Web of Science (1985 to May 2013), CAB Abstracts (1985 to May 2013), LILACS (1982 to May 2013) and prospective trials registries to May 2013. Randomised controlled trials (RCTs) or quasi-RCTs comparing antibiotics versus placebo or no intervention, in people with suspected meningococcal infection, or different antibiotics administered before admission to hospital or confirmation of the diagnosis. Two review authors independently assessed trial quality and extracted data from the search results. We calculated the risk ratio (RR) and 95% confidence interval (CI) for dichotomous data. We included only one trial so data synthesis was not performed. We assessed the overall quality of the evidence using the GRADE approach. We found no RCTs that compared pre-admission antibiotics versus no pre-admission antibiotics or placebo. One open-label, non-inferiority RCT, conducted during an epidemic in Niger, evaluated a single dose of intramuscular ceftriaxone versus a single dose of intramuscular long-acting (oily) chloramphenicol. Ceftriaxone was not inferior to chloramphenicol in reducing mortality (RR 1.2, 95% CI 0.6 to 2.6; N = 503; 308 confirmed meningococcal meningitis; 26 deaths; moderate-quality evidence), clinical failures (RR 0.8, 95% CI 0.3 to 2.2; N = 477, 18 clinical failures; moderate-quality evidence) or neurological sequelae (RR 1.3, 95% CI 0.6 to 2.6; N

  8. Microbiology of pediatric orbital cellulitis.

    Science.gov (United States)

    McKinley, Steven H; Yen, Michael T; Miller, Aaron M; Yen, Kimberly G

    2007-10-01

    To evaluate the microbiology of pediatric orbital cellulitis associated with sinusitis. Retrospective review of medical records of pediatric patients treated for orbital cellulitis. All pediatric patients treated for orbital cellulitis associated with sinusitis at Texas Children's Hospital between December 1, 2001 and September 30, 2005 were reviewed. Data collected included patient age, history, microbiology results, and surgical intervention. Thirty-eight cases were identified. Fifteen cases required medical management, whereas 23 patients received a combination of medical and surgical intervention. Three patients had multiple surgical procedures performed. Of the procedures performed, four were sinus irrigation, 12 were sinusotomy and drainage, nine were orbitotomy with drainage of abscess, and one was craniotomy with drainage of abscess. Surgical aspirate specimens yielded a higher positive culture result rate with 9/9 of orbital abscesses and 13/16 of sinus aspirates demonstrating a positive yield. Two of the 27 blood cultures had a positive yield. Staphylococcus species was the most common organism isolated. Methicillin-resistant S. aureus (MRSA) represented 73% of S. aureus isolates. Streptococcus species was the next most common pathogen. Three cultures yielded Haemophilus species with one being positive for H. influenzae. Organisms responsible for causing pediatric orbital cellulitis are evolving, with Staphylococcus followed by Streptococcus species being the most common pathogens. The occurrence of MRSA in pediatric orbital cellulitis is increasing, and empiric antimicrobial therapy should be directed against these organisms if they are prevalent in the community. Sinus and orbital abscess aspirates yielded the greatest number of positive cultures, though these invasive surgical procedures should be performed only when clinically indicated.

  9. Warner Prize Lecture: A New View on Planetary Orbital Dynamics

    Science.gov (United States)

    Ford, Eric B.

    2013-01-01

    Prior to the discovery of exoplanets, astronomers fine tuned theories of planet formation to explain detailed properties of the solar system. Doppler planet searches revealed that many giant planets orbit close to their host star or in highly eccentric orbits. These and subsequent observations inspired new theories of planet formation that invoke strong mutual gravitation interactions in multiple planet systems to explain the excitation of orbital eccentricities and even short-period giant planets. NASA's Kepler mission has identified over 300 systems with multiple transiting planet candidates, including many potentially rocky planets. Most of these systems include multiple planets with sizes between Earth and Neptune and closely-spaced orbits. These systems represent another new and unexpected class of planetary systems and provide an opportunity to test the theories developed to explain the properties of giant exoplanets. I will describe how transit timing observations by Kepler are characterizing the gravitational effects of mutual planetary perturbations for hundreds of planets and providing precise (but complex) constraints on planetary masses, densities and orbits, even for planetary systems with faint host stars. I will discuss early efforts to translate these observations into new constraints on the formation and orbital evolution of planetary systems with low-mass planets.

  10. Orbital complexity in a time-dependent potential

    Science.gov (United States)

    Boily, C. M.; Detemple, L.; Faber, N. T.

    2008-12-01

    We introduce a method to detect irregular or chaotic orbits in gravitational potentials based on a wavelet transform of stellar orbits. The method is based on a treatment of normalised frequency power-spectrum coefficients, which we interpret as occupation probabilities (or, weights) of individual frequency modes. Each probability is fed to a Shannon information-entropy formula, before summing over the whole spectrum to compute the total entropy \\cal S. This entropy is then monitored in time as the wavelet coefficients change: each orbit is classified as regular or not according to \\cal S and its dispersion. We find that diagrams of entropy versus entropy dispersion allow to identify orbits in a simple and efficient way, similarly to surface-of-section analysis but requiring less integration time. We apply the method to the case of a gravitational potential modulated by the periodic motion of a massive black hole and find that some 19% of stars are now shifted to highly irregular motion as a result of black hole orbital motion. This is the same fraction of stars that orbit within the black hole radius of influence. This is thanks ..

  11. Treatment of Orbital Complications Following Acute Rhinosinusitis in Children.

    Science.gov (United States)

    Wan, Yuzhu; Shi, Guanggang; Wang, Haibo

    2016-07-01

    The orbital complications account for about 80% of all complications secondary to acute rhinosinusitis. If the treatment is not correct and in time, orbital complications could progress rapidly, leading to optic neuritis, cavernous sinus thrombophlebitis or life-threatening intracranial complications. To evaluate the therapeutic efficacy of conservative therapy for the patients with orbital cellulitis and endoscopic sinus surgery (ESS) performed on patients with subperiosteal abscess (SPA) secondary to acute rhinosinusitis in children. Retrospective cross-sectional study. The retrospective study included 31 pediatric patients with orbital complications secondary to acute rhinosinusitis. In all cases, intensive treatment was initiated with a combination of oral or intravenous antibiotics, glucocorticoid and gelomyrtol forte after admission. ESS was performed if an improvement in the condition of patients did not occur after 48 hours. However, the patients with orbital SPA, motility disorders of eyeball or decreased vision received ESS immediately within 24 hours. Sixteen patients were cured by conservative therapy and 15 patients by ESS. All of the signs and symptoms disappeared after conservative therapy or ESS. There were no recurrences within the follow-up period of 1 to 8 years. Conservative therapy is an effective method for patients with inflammatory edema and most cases of orbital cellulitis in children. SPA can be cured by ESS.

  12. Fourier Series Approximations to J2-Bounded Equatorial Orbits

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2014-01-01

    Full Text Available The current paper offers a comprehensive dynamical analysis and Fourier series approximations of J2-bounded equatorial orbits. The initial conditions of heterogeneous families of J2-perturbed equatorial orbits are determined first. Then the characteristics of two types of J2-bounded orbits, namely, pseudo-elliptic orbit and critical circular orbit, are studied. Due to the ambiguity of the closed-form solutions which comprise the elliptic integrals and Jacobian elliptic functions, showing little physical insight into the problem, a new scheme, termed Fourier series expansion, is adopted for approximation herein. Based on least-squares fitting to the coefficients, the solutions are expressed with arbitrary high-order Fourier series, since the radius and the flight time vary periodically as a function of the polar angle. As a consequence, the solutions can be written in terms of elementary functions such as cosines, rather than complex mathematical functions. Simulations enhance the proposed approximation method, showing bounded and negligible deviations. The approximation results show a promising prospect in preliminary orbits design, determination, and transfers for low-altitude spacecrafts.

  13. Suspected vitreous seeding of uveal melanoma: relevance of diagnostic vitrectomy.

    Science.gov (United States)

    Metz, Claudia H D; Bornfeld, Norbert; Metz, Klaus A; Gök, Mete

    2016-05-01

    To review all cases of suspected vitreous seeding of treated or untreated uveal melanoma at our clinic and to compare clinical, cytological and histological findings with patients' survival. Retrospective non-randomised study of 23 patients with consecutive uveal melanoma who underwent diagnostic vitrectomy in our clinic between January 2000 and November 2013. Reason for vitrectomy was suspected dissemination of tumour cells inside the eye. Treated as well as treatment-naïve primary uveal melanomas were included in this study. Follow-up data of all patients were collected. The study included 23 patients with a mean age of 66 years. Four patients presented pigmented vitreous debris at initial presentation prior to treatment of the uveal melanoma. All but one of these four patients has been enucleated as a consequence of cytology-proven vitreous spreading of vital melanoma cells. The remaining 19 patients presented pigmented vitreous debris at a mean of 60 months following local tumour treatment. Thirteen of these patients had been treated with a ruthenium plaque (mean scleral dose 1295 Gy, mean apex dose 152 Gy), three with binuclid plaque (mean scleral dose 1005 Gy, mean apex dose 70 Gy) and three with proton beam radiation. Of the 19 patients, 10 showed only melanophages in the vitreous specimen, while the remaining 9 patients had vital tumour cells in vitreous cytology. Four out of these nine patients have been enucleated in the course of follow-up. During follow-up of our cohort of 23 patients, 4 patients died, but only 1 of them due to metastatic disease. The outcome of this small cohort study shows that obtaining a vitreous specimen helps to distinguish melanophages from vital tumour cells. We could not observe an increased risk of metastasis in patients who showed melanoma cell dissemination inside the eye, compared with those patients only showing melanophages. We therefore suggest to carefully re-evaluate the necessity of enucleation in every

  14. Cost analysis of inappropriate treatments for suspected dermatomycoses

    Directory of Open Access Journals (Sweden)

    Emanuela Fiammenghi

    2015-06-01

    Full Text Available Superficial mycoses are estimated to affect more than 20-25% of the world’s population with a consistent increase over the years. Most patients referred to our clinic for suspected dermatomycoses have already been treated with pharmacotherapy, without a previous mycological examination and many show changes in the clinical manifestations. Indeed, some medications, such as steroids, antiviral, antibiotics and antihistamines are not able to erase a fungal infection, but also they can cause atypical clinical manifestations. The consequences of inappropriate treatment include delayed diagnosis, prolonged healing time, and additional costs. The aims of this study were (1 to evaluate the incidence of increased costs attributable to inappropriate therapy sustained by the National Health Service and patients and (2 to highlight the importance of mycological evaluation before starting treatment, in order to improve diagnostic accuracy. An observational retrospective and prospective study was performed from September 2013 to February 2014, in 765 patients referred to our center (University Hospital “ Federico II” in Naples, Italy, for suspected mycological infection. The following treatments (alone or in combination were defined as inappropriate: (1 cortisone in a patient with at least one positive site; (2 antifungals in (a patients with all negative sites or (b ineffective antifungal treatment (in terms of drug chosen, dose or duration in those with all positive sites; or (3 antibiotics; (4 antivirals or (5 antihistamines, in patients with ≥ 1 positive site. Five hundred and fifty patients were using medications before the assessment visit. The total amount of avoidable costs related to inappropriate previous treatments was € 121,417, representing 74% of the total treatment costs. 253/550 patients received drugs also after the visit. For these patients, the cost of treatment prescribed after mycological testing was € 42,952, with a decrease

  15. Developmentally Delayed Male with Mincer Blade Obstructing the Oesophagus for a Period of Time Suspected to Be 6 Months

    Directory of Open Access Journals (Sweden)

    Christian Grønhøj Larsen

    2015-01-01

    Full Text Available Introduction. Sharp, retained foreign bodies in the oesophagus are associated with severe complications. Developmentally delayed patients are especially subject to foreign objects. We describe a 37-year-old, developmentally delayed male with a mincer blade obstructing the oesophagus. Six months prior to surgical intervention, the patient was hospitalized in a condition of sepsis and pneumonia where the thoracic X-ray reveals a foreign body in the proximal oesophagus. When rehospitalized 6 months later, a mincer blade of the type used in immersion blenders was surgically removed. During these 6 months the patient’s main symptoms were dysphagia, weight loss, and diarrhoea. When developmentally delayed patients present with dysphagia, we strongly encourage the awareness of the possible presence of foreign bodies. To our knowledge this is the first reported case of a mincer blade in the oesophagus.

  16. Developmentally Delayed Male with Mincer Blade Obstructing the Oesophagus for a Period of Time Suspected to Be 6 Months

    DEFF Research Database (Denmark)

    Larsen, Christian Grønhøj; Charabi, Birgitte

    2015-01-01

    Introduction. Sharp, retained foreign bodies in the oesophagus are associated with severe complications. Developmentally delayed patients are especially subject to foreign objects. We describe a 37-year-old, developmentally delayed male with a mincer blade obstructing the oesophagus. Six months p...

  17. Evolution of periodicity in periodical cicadas.

    Science.gov (United States)

    Ito, Hiromu; Kakishima, Satoshi; Uehara, Takashi; Morita, Satoru; Koyama, Takuya; Sota, Teiji; Cooley, John R; Yoshimura, Jin

    2015-09-14

    Periodical cicadas (Magicicada spp.) in the USA are famous for their unique prime-numbered life cycles of 13 and 17 years and their nearly perfectly synchronized mass emergences. Because almost all known species of cicada are non-periodical, periodicity is assumed to be a derived state. A leading hypothesis for the evolution of periodicity in Magicicada implicates the decline in average temperature during glacial periods. During the evolution of periodicity, the determinant of maturation in ancestral cicadas is hypothesized to have switched from size dependence to time (period) dependence. The selection for the prime-numbered cycles should have taken place only after the fixation of periodicity. Here, we build an individual-based model of cicadas under conditions of climatic cooling to explore the fixation of periodicity. In our model, under cold environments, extremely long juvenile stages lead to extremely low adult densities, limiting mating opportunities and favouring the evolution of synchronized emergence. Our results indicate that these changes, which were triggered by glacial cooling, could have led to the fixation of periodicity in the non-periodical ancestors.

  18. Sticky orbits in a kicked-oscillator model

    CERN Document Server

    Lowenstein, J H; Vivaldi, F

    2005-01-01

    We study a 4-fold symmetric kicked-oscillator map with sawtooth kick function. For the values of the kick amplitude $\\lambda=2\\cos(2\\pi p/q)$ with rational $p/q$, the dynamics is known to be pseudochaotic, with no stochastic web of non-zero Lebesgue measure. We show that this system can be represented as a piecewise affine map of the unit square ---the so-called local map--- driving a lattice map. We develop a framework for the study of long-time behaviour of the orbits, in the case in which the local map features exact scaling. We apply this method to several quadratic irrational values of $\\lambda$, for which the local map possesses a full Legesgue measure of periodic orbits; these are promoted to either periodic orbits or accelerator modes of the kicked-oscillator map. By constrast, the aperiodic orbits of the local map can generate various asymptotic behaviours. For some parameter values the orbits remain bounded, while others have excursions which grow logarithmically or as a power of the time. In the po...

  19. Choosing a strategy for the diagnostic management of suspected scaphoid fracture: a cost-effectiveness analysis.

    Science.gov (United States)

    Tiel-van Buul, M M; Broekhuizen, T H; van Beek, E J; Bossuyt, P M

    1995-01-01

    To assess the cost-effectiveness of various strategies for the diagnostic management of clinically suspected scaphoid fracture, a decision-analytic model was built to evaluate three strategies and to compare them with a (clairvoyant) reference diagnostic management strategy. Evaluated strategies were: (A) repeated radiography up to 2 wk; (B) repeat radiography up to 6 wk; and (C) radiography, followed by bone scintigraphy in patients with negative initial radiographs. Therapy consisted of 12 wk of immobilization for a radiographically or scintigraphically proven fracture. Diagnostic costs, therapeutic costs, period of immobilization and nonunion rate were calculated for all three strategies. Estimates were derived from a descriptive management study using bone scintigraphy and available literature. Sensitivity analyses were performed. Overall costs were 273.7, 317.7 and 316.1 European Currency Units (ECU) for Strategies A, B and C, respectively (1 ECU = 1.15 U.S. dollar). Strategy B led to the longest average period of immobilization (8.6 wk), while Strategy A resulted in the highest nonunion rate (4.7%). The costs per nonunion saved for the additional use of bone scintigraphy (Strategy C) was ECU 2618 when compared to Strategy A. The use of bone scintigraphy in the diagnostic management of scaphoid fractures is accurate, convenient for patients and cost-effective.

  20. Successful Treatment of Suspected Pulmonary Arterial Hypertension in a Mealy Amazon Parrot (Amazona farinose).

    Science.gov (United States)

    Brady, Sean M; Burgdorf-Moisuk, Anne; Silverman, Sarah; Wack, Raymund F

    2016-12-01

    A 25-year-old, male mealy Amazon parrot (Amazona farinose) with a history of polycythemia, hepatomegaly, and epistaxis was evaluated for progressive lethargy and anorexia. Clinical laboratory testing revealed severe polycythemia (71%), hypophosphatemia (1.6 mg/dL), and mild hypokalemia (2.8 mEq/L). Radiographs showed marked hepatomegaly and loss of air sac space. Despite supportive treatments, the bird's condition deteriorated, and it developed ataxia, was unable to fly, and became oxygen dependent. An echocardiogram, including an air bubble study, revealed a right-to-left atrial shunt and presumed pulmonary arterial hypertension. The bird was started on periodic phlebotomy (5-10 mL/kg q6wk) to reduce packed cell volume and sildenafil citrate (2.5 mg/kg PO q8h) for treatment of suspected pulmonary arterial hypertension. One week later, the patient was weaned off oxygen, and 24 days after initial presentation, the parrot was returned to its outdoor exhibit. Intermittent periods of increased respiratory rate and effort have been reported but have resolved without additional treatments. Epistaxis, once common in this bird, has not been noted since initiating treatment with sildenafil citrate 15 months ago.

  1. A refined orbit for the satellite of asteroid (107) Camilla

    Science.gov (United States)

    Pajuelo, Myriam Virginia; Carry, Benoit; Vachier, Frederic; Berthier, Jerome; Descamp, Pascal; Merline, William J.; Tamblyn, Peter M.; Conrad, Al; Storrs, Alex; Margot, Jean-Luc; Marchis, Frank; Kervella, Pierre; Girard, Julien H.

    2015-11-01

    The satellite of the Cybele asteroid (107) Camilla was discovered in March 2001 using the Hubble Space Telescope (Storrs et al., 2001, IAUC 7599). From a set of 23 positions derived from adaptive optics observations obtained over three years with the ESO VLT, Keck-II and Gemini-North telescopes, Marchis et al. (2008, Icarus 196) determined its orbit to be nearly circular.In the new work reported here, we compiled, reduced, and analyzed observations at 39 epochs (including the 23 positions previously analyzed) by adding additional observations taken from data archives: HST in 2001; Keck in 2002, 2003, and 2009; Gemini in 2010; and VLT in 2011. The present dataset hence contains twice as many epochs as the prior analysis and covers a time span that is three times longer (more than a decade).We use our orbit determination algorithm Genoid (GENetic Orbit IDentification), a genetic based algorithm that relies on a metaheuristic method and a dynamical model of the Solar System (Vachier et al., 2012, A&A 543). The method uses two models: a simple Keplerian model to minimize the search-time for an orbital solution, exploring a wide space of solutions; and a full N-body problem that includes the gravitational field of the primary asteroid up to 4th order.The orbit we derive fits all 39 observed positions of the satellite with an RMS residual of only milli-arcseconds, which corresponds to sub-pixel accuracy. We found the orbit of the satellite to be circular and roughly aligned with the equatorial plane of Camilla. The refined mass of the system is (12 ± 1) x 10^18 kg, for an orbital period of 3.71 days.We will present this improved orbital solution of the satellite of Camilla, as well as predictions for upcoming stellar occultation events.

  2. Science Planning and Orbit Classification for Solar Probe Plus

    Science.gov (United States)

    Kusterer, M. B.; Fox, N. J.; Rodgers, D. J.; Turner, F. S.

    2016-12-01

    There are a number of challenges for the Science Planning Team (SPT) of the Solar Probe Plus (SPP) Mission. Since SPP is using a decoupled payload operations approach, tight coordination between the mission operations and payload teams will be required. The payload teams must manage the volume of data that they write to the spacecraft solid-state recorders (SSR) for their individual instruments for downlink to the ground. Making this process more difficult, the geometry of the celestial bodies and the spacecraft during some of the SPP mission orbits cause limited uplink and downlink opportunities. The payload teams will also be required to coordinate power on opportunities, command uplink opportunities, and data transfers from instrument memory to the spacecraft SSR with the operation team. The SPT also intend to coordinate observations with other spacecraft and ground based systems. To solve these challenges, detailed orbit activity planning is required in advance for each orbit. An orbit planning process is being created to facilitate the coordination of spacecraft and payload activities for each orbit. An interactive Science Planning Tool is being designed to integrate the payload data volume and priority allocations, spacecraft ephemeris, attitude, downlink and uplink schedules, spacecraft and payload activities, and other spacecraft ephemeris. It will be used during science planning to select the instrument data priorities and data volumes that satisfy the orbit data volume constraints and power on, command uplink and data transfer time periods. To aid in the initial stages of science planning we have created an orbit classification scheme based on downlink availability and significant science events. Different types of challenges arise in the management of science data driven by orbital geometry and operational constraints, and this scheme attempts to identify the patterns that emerge.

  3. Featured Image: Globular Cluster Orbits

    Science.gov (United States)

    Kohler, Susanna

    2017-04-01

    This figure (click for the full view) shows the meridional galactic orbits of 12 globular clusters that orbit the Milky Way. The recent release of stellar parallax data from Gaia allowed a team of scientists at Dartmouth College to improve measurements of a number of galactic globular clusters very old clusters of stars that can either orbit within the galactic disk and bulge or more distantly in the galactic halo. In a recent publication led by Erin OMalley, the team presents their findings and combines their new measurements for the clusters with proper motions from past studies to calculate the orbits that these globulars take. These calculations show us whether the clusters reside in the galactic disk and bulge (as only NGC 104 does in the sample shown here, since its orbit is confined to 8 kpc radially and 4 kpc vertically of the galactic center), or if they are halo clusters. To learn more about the authors work, you can check out the paper below!CitationErin M. OMalley et al 2017 ApJ 838 162. doi:10.3847/1538-4357/aa6574

  4. Orbital positioning and stationkeeping of geostationary satellites

    Science.gov (United States)

    Donat, H.

    Orbit, launcher, and satellite related constraints on launch windows are reviewed. The flight sequence and orbital position optimization of spin and three axis stabilized satellites are described. Geostationary orbit perturbations and evolution, and orbit correction are considered. North-south and east-west stationkeeping strategies are outlined. Stationkeeping of Telecom-1 and TDF-1 is illustrated.

  5. ORBITAL CELLULITIS COMPLICATING SINUSITIS: A 15-YEAR ...

    African Journals Online (AJOL)

    Dr. NWaorgu

    Abstract. Background: Orbital cellulitis is an infection of the orbital soft tissues behind the orbital septum. Primary sinus infection is the most common cause of orbital cellulites. It is an ocular emergency that threatens not only vision but also life from complications such as meningitis, cavernous sinus thrombosis, and brain ...

  6. Understanding Pediatric Bacterial Preseptal and Orbital Cellulitis

    OpenAIRE

    Gonzalez, Mithra O.; Durairaj, Vikram D.

    2010-01-01

    Pediatric preseptal and orbital cellulitis are infectious disorders that result in periorbital inflammation. Preseptal cellulitis is often associated with breaches in the skin barrier whereas orbital cellulitis is commonly associated with paranasal sinusitis. Orbital cellulitis may be associated with subperiosteal abscess. It is important to distinguish between preseptal from orbital cellulitis. Clinical examination and diagnostic imaging are useful in determining appropriate management. Pati...

  7. [Suspected pathogenic mutation identified in two cases with oculocutaneous albinism].

    Science.gov (United States)

    He, Jiangmei; Zheng, Meiling; Zhang, Guilin; Hua, Ailing

    2015-08-01

    To detect potential mutations in genes related with non-syndromic oculocutaneous albinism I-IV and ocular albinism type I in two couples who had given births to children with albinism. All exons of the non-syndromic albinism related genes TYR, OCA2, TYRP-1, MITF, SLC45A2 and GPR143 were subjected to deep sequencing. The results were verified with Sanger sequencing. For the two female carriers, the coding region of the TYR gene was found to harbor a frameshift mutation c.925_926insC, which was also suspected to have been pathogenic. In one of the male partners, a nonsense mutations c.832C>T was found, which was also known to be pathogenic. Another male partner was found to harbor a TYR gene mutation c.346C>T, which was also known to be a pathogenic nonsense mutation. The coding region of the TYR gene c.925_926insC (p.Thr309ThrfsX9) probably underlies the OCA1 disease phenotype.

  8. Chest pain and behavior in suspected coronary artery disease.

    Science.gov (United States)

    Young, L D; Barboriak, J J; Anderson, A J

    1988-01-01

    This study assessed behavioral activity, dietary and emotional variables among patient cohorts with angina pectoris, atypical chest pain, and no chest pain in whom coronary disease is suspected. Questionnaire responses of 3,899 employed male patients at the time of coronary arteriography were analyzed. Patients with angina pectoris had high levels of coronary-prone and neurotic attitudes, and fatigue variables including feeling unrested on awakening, easy fatiguability, reducing activity at work and arriving home tired. Atypical chest pain patients showed coronary-prone and neurotic attitudes similar to the angina pectoris group but had less coronary occlusion and lower levels of fatigue variables. Compared to the other groups, atypical chest pain patients were more likely to skip breakfast and showed a trend to eat fast. These findings suggest that including assessment of activity levels, fatiguability, eating behavior, neurotic traits and coronary-prone attitudes at time of coronary arteriography can have some limited value for patients with chest pain who may seek cardiac treatment but could benefit from alternative approaches.

  9. [Predictive value of procalcitonin in children with suspected sepsis].

    Science.gov (United States)

    Bustos B, Raúl; Padilla P, Oslando

    2015-01-01

    The use of biomarkers could be a tool for diagnosis, prognosis and stratifying children with sepsis. Our main goal was to analyze the value of procalcitonin (PCT), C reactive protein (CRP) and lactate in predicting mortality, septic shock and the stratification in children with suspected sepsis Prospective study in 81 patients. Plasma levels of PCT, CRP and lactate were measured at admission in the pediatric intensive care unit. Patients were categorized into systemic inflammatory response syndrome, sepsis, severe sepsis and septic shock. Concentrations of PCT (ng/mL) increased significantly according to the severity of sepsis: 0.36 (0-1.2) for systemic inflammatory response syndrome; 1.96 (0.4-3.5) for sepsis; 7.5 (3.9-11.1) for severe sepsis; and 58.9 (35.1-82.7) for septic shock (P<.001). Compared to CRP and lactate, the area under the ROC curve revealed a good discriminative power of PCT to predict septic shock and mortality, 0.91 (95% CI: 0.83-0.97) and 0.80 (95% CI: 0.69-0.88), respectively. In contrast to CRP and lactate, the determination of PCT in pediatric intensive care unit admission is a good predictor of mortality and septic shock and can stratify patients according to severity of sepsis. Copyright © 2015 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. The optimal diagnostic workup for children with suspected food allergy.

    Science.gov (United States)

    Berni Canani, Roberto; Di Costanzo, Mara; Troncone, Riccardo

    2011-10-01

    Food allergy is defined as an abnormal immunologic reaction to food proteins that causes an adverse clinical reaction. In addition to well-known acute allergic reactions and anaphylaxis triggered by immunoglobulin E antibody-mediated immune responses to food proteins, there is an increasing recognition of cell-mediated disorders such as eosinophilic esophagitis and food protein-induced enterocolitis syndrome. More than 90% of food allergies in childhood are caused by eight foods: cow's milk, hen's egg, soy, peanuts, tree nuts, wheat, fish, and shellfish. The diagnostic workup for a child with suspected food allergy includes a detailed medical history, physical examination, food allergy screening tests, and responses to an elimination diet and an oral food challenge. None of the screening tests, alone or in combination, can definitely diagnose or exclude a food allergy. Novel diagnostic methods including those that focus on immune responses to specific food proteins or epitopes of specific proteins are under active study. Unconventional diagnostic methods are increasingly used, but they lack scientific rationale, standardization, and reproducibility. In selected cases, such as eosinophilic esophageal gastroenteropathies or food protein-induced gastroesophageal reflux disease, invasive procedures are mandatory for an accurate diagnosis. Properly done, an oral food challenge is still the gold standard in the diagnostic workup. An incorrect diagnosis is likely to result in unnecessary dietary restrictions, which, if prolonged, may adversely affect the child's nutritional status and growth. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Control of Suspect/Counterfeit and Defective Items

    Energy Technology Data Exchange (ETDEWEB)

    Sheriff, Marnelle L.

    2013-09-03

    This procedure implements portions of the requirements of MSC-MP-599, Quality Assurance Program Description. It establishes the Mission Support Alliance (MSA) practices for minimizing the introduction of and identifying, documenting, dispositioning, reporting, controlling, and disposing of suspect/counterfeit and defective items (S/CIs). employees whose work scope relates to Safety Systems (i.e., Safety Class [SC] or Safety Significant [SS] items), non-safety systems and other applications (i.e., General Service [GS]) where engineering has determined that their use could result in a potential safety hazard. MSA implements an effective Quality Assurance (QA) Program providing a comprehensive network of controls and verification providing defense-in-depth by preventing the introduction of S/CIs through the design, procurement, construction, operation, maintenance, and modification of processes. This procedure focuses on those safety systems, and other systems, including critical load paths of lifting equipment, where the introduction of S/CIs would have the greatest potential for creating unsafe conditions.

  12. Relative Orbit Elements for Satellites in Elliptical Orbits

    Science.gov (United States)

    2010-03-01

    flying missions [9, 35, 63, 75, 95, 107, 111], such as the European PRISMA mission [22], NASA’s Magnetosphere Multiscale mission [21, 34, 62, 80, 109...Magnetosphere Multiscale (MMS) Mission, 1999. [22] D’Amico, S., Gill, E., and Montenbruck, O., “Relative Orbit Control Design for the PRISMA Formation

  13. Assessing Terra Disposal Orbit Candidates from an Orbital Debris Perspective

    Science.gov (United States)

    Abraham, Andrew J.; Thompson, Roger C.; Mantziaras, Dimitrios C.

    2016-01-01

    The NASA Terra satellite is reaching the end of its mission life. Because the satellite resides in the 705 km Earth Science Constellation, disposal strategies need to be considered to remove it from this densely populated operational orbit. Of critical importance was the need to examine the future potential risk to other satellite residents of the 705 km constellation due to an unexpected breakup event of the Terra satellite post-disposal. This study quantifies the comparative risk of debris impacts associated with the two leading candidate disposal orbits (701 km vs. 686 km) and characterizes the suitability of each orbit for the purpose of long-term spacecraft disposal. The increase in collision risk to any member of the 705 km Earth Science Constellation is very modest. The long-term, average, total risk (including the ambient background risk) due to a Terra breakup at a disposal of -19 km (i.e., 686 km) relative to the 705 km constellation is 9.7 × 10(exp -6) impacts/day versus 1.0 × 10(exp -5) impacts/day for a disposal of only -4 km (i.e., 701 km). For perspective, note that the nominal space background risk to the 705 km constellation is 9.2 × 10(exp -6) impacts/day which implies a very modest increase in risk (approximately 3% difference between the two cases) due to a Terra breakup in either disposal orbit.

  14. AA, closed orbit observation pickup

    CERN Multimedia

    1980-01-01

    Electrostatic pickups around the circumference of the AA served for the measurement of the closed orbits across the wide momentum range of +- 3% to either side of central orbit. The pickups were of the "shoebox" type, with diagonal cuts, a horizontal and a vertical one mechanically coupled together. They were located where they would not require extra space. The small ones, like the one we see here, were inserted into the vacuum chamber of the BLG (long and narrow) bending magnets. See also 8001372, 8010042, 8010045

  15. AA, closed orbit observation pickup

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    Electrostatic pickups around the circumference of the AA served for the measurement of the closed orbits across the wide momentum range of +- 3% to either side of central orbit. The pickups were of the "shoebox" type, with diagonal cuts, a horizontal and a vertical one mechanically coupled together. They were located where they would not require extra space. The wide ones (very wide indeed: 70 cm), like the one we see here, were placed inside the vacuum chamber of the wide quadrupoles QFW, at maximum dispersion. See also 8001372, 8001383, 8010045

  16. AA, closed orbit observation pickup

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    Electrostatic pickups around the circumference of the AA served for the measurement of the closed orbits across the wide momentum range of +- 3% to either side of central orbit. The pickups were of the "shoebox" type, with diagonal cuts, a horizontal and a vertical one mechanically coupled together. They were located where they would not require extra space. The small ones, like the one we see here, were inserted into the vacuum chamber of the BLG (long and narrow) bending magnets. Werner Sax contemplates his achievement. See also 8001383, 8010042, 8010045.

  17. AA, closed orbit observation pickup

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    Electrostatic pickups around the circumference of the AA served for the measurement of the closed orbits across the wide momentum range of +- 3% to either side of central orbit. The pickups were of the "shoebox" type, with diagonal cuts, a horizontal and a vertical one mechanically coupled together. They were located where they would not require extra space. The wide ones (very wide indeed: 70 cm), like the one we see here, were placed inside the vacuum chamber of the wide quadrupoles, QFW, at maximum dispersion. See also 8001372,8001383, 8010042

  18. Orbital resonances around black holes.

    Science.gov (United States)

    Brink, Jeandrew; Geyer, Marisa; Hinderer, Tanja

    2015-02-27

    We compute the length and time scales associated with resonant orbits around Kerr black holes for all orbital and spin parameters. Resonance-induced effects are potentially observable when the Event Horizon Telescope resolves the inner structure of Sgr A*, when space-based gravitational wave detectors record phase shifts in the waveform during the resonant passage of a compact object spiraling into the black hole, or in the frequencies of quasiperiodic oscillations for accreting black holes. The onset of geodesic chaos for non-Kerr spacetimes should occur at the resonance locations quantified here.

  19. A Search for Exoplanets in Short-Period Binary Star Systems

    Directory of Open Access Journals (Sweden)

    Ronald Kaitchuck

    2012-03-01

    Full Text Available This paper reports the progress of a search for exoplanets with S-type orbits in short-period binary star systems. The selected targets have stellar orbital periods of just a few days. These systems are eclipsing binaries so that exoplanet transits, if planets exist, will be highly likely. We report the results for seven binary star systems.

  20. Orbital-only models: ordering and excitations

    Science.gov (United States)

    van den Brink, Jeroen

    2004-12-01

    We consider orbital-only models in Mott insulators, where the orbital orbital interactions are either due to Jahn Teller distortions or due to the Kugel Khomskii superexchange. This leads to highly anisotropic and frustrated orbital Hamiltonians. For two-fold degenerate eg systems, both types of orbital interactions lead to the same form of the Hamiltonian—the 120° model. In both cases, the predicted symmetry of the orbital ordering is the same, although different from the one observed experimentally. The orbital operators that appear in the two kinds of orbital-only Hamiltonians are different. In the case of superexchange, the orbital degrees of freedom are represented by quantum pseudo-spin 1/2 operators. But when the interactions are Jahn Teller mediated and the coupling with the lattice is strong, the orbital operators are essentially classical pseudospins. Thus as a function of the relative coupling strengths, a quantum-to-classical crossover is expected. For three-fold degenerate t2g orbitals, the Jahn Teller coupling gives rise to a particular type of orbital compass models. We point out that fluctuations—whether due to quantum effects or finite temperature—are of prime importance for ordering in the 120° and orbital compass models. The fluctuations generally generate a gap in the orbital excitation spectrum. These orbital excitations—orbitons—are hybrid excitations that carry both a lattice Jahn Teller and a magnetic Kugel Khomskii character.