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Sample records for plasma-dynamic explorer apex

  1. Introduction to plasma dynamics

    CERN Document Server

    Morozov, A I

    2013-01-01

    As the twenty-first century progresses, plasma technology will play an increasing role in our lives, providing new sources of energy, ion-plasma processing of materials, wave electromagnetic radiation sources, space plasma thrusters, and more. Studies of the plasma state of matter not only accelerate technological developments but also improve the understanding of natural phenomena. Beginning with an introduction to the characteristics and types of plasmas, Introduction to Plasma Dynamics covers the basic models of classical diffuse plasmas used to describe such phenomena as linear and shock w

  2. Learning Apex programming

    CERN Document Server

    Kaufman, Matt

    2015-01-01

    If you are a developer who has some object-oriented programming experience, Learning Apex Programming is the perfect book for you. This book is most appropriate for developers who wish to gain an understanding of the Force.com platform and how to use Apex to create business applications.

  3. Plasma dynamics in current sheets

    International Nuclear Information System (INIS)

    Bogdanov, S.Yu.; Drejden, G.V.; Kirij, N.P.; AN SSSR, Leningrad

    1992-01-01

    Plasma dynamics in successive stages of current sheet evolution is investigated on the base of analysis of time-spatial variations of electron density and electrodynamic force fields. Current sheet formation is realized in a two-dimensional magnetic field with zero line under the action of relatively small initial disturbances (linear regimes). It is established that in the limits of the formed sheet is concentrated dense (N e ∼= 10 16 cm -3 ) (T i ≥ 100 eV, bar-Z i ≥ 2) hot pressure of which is balanced by the magnetic action of electrodynamic forces is carried out both plasma compression in the sheet limits and the acceleration along the sheet surface from a middle to narrow side edges

  4. Coherent control of plasma dynamics

    Science.gov (United States)

    He, Zhaohan

    2014-10-01

    The concept of coherent control - precise measurement or determination of a process through control of the phase of an applied oscillating field - has been applied to numerous systems with great success. Here, we demonstrate the use of coherent control on plasma dynamics in a laser wakefield electron acceleration experiment. A tightly focused femtosecond laser pulse (10 mJ, 35 fs) was used to generate electron beams by plasma wakefield acceleration in the density down ramp. The technique is based on optimization of the electron beam using a deformable mirror adaptive optical system with an iterative evolutionary genetic algorithm. The image of the electrons on a scintillator screen was processed and used in a fitness function as direct feedback for the optimization algorithm. This coherent manipulation of the laser wavefront leads to orders of magnitude improvement to the electron beam properties such as the peak charge and beam divergence. The laser beam optimized to generate the best electron beam was not the one with the ``best'' focal spot. When a particular wavefront of laser light interacts with plasma, it can affect the plasma wave structures and trapping conditions of the electrons in a complex way. For example, Raman forward scattering, envelope self-modulation, relativistic self-focusing, and relativistic self-phase modulation and many other nonlinear interactions modify both the pulse envelope and phase as the pulse propagates, in a way that cannot be easily predicted and that subsequently dictates the formation of plasma waves. The optimal wavefront could be successfully determined via the heuristic search under laser-plasma conditions that were not known a priori. Control and shaping of the electron energy distribution was found to be less effective, but was still possible. Particle-in-cell simulations were performed to show that the mode structure of the laser beam can affect the plasma wave structure and trapping conditions of electrons, which

  5. Natural Poisson structures of nonlinear plasma dynamics

    International Nuclear Information System (INIS)

    Kaufman, A.N.

    1982-01-01

    Hamiltonian field theories, for models of nonlinear plasma dynamics, require a Poisson bracket structure for functionals of the field variables. These are presented, applied, and derived for several sets of field variables: coherent waves, incoherent waves, particle distributions, and multifluid electrodynamics. Parametric coupling of waves and plasma yields concise expressions for ponderomotive effects (in kinetic and fluid models) and for induced scattering. (Auth.)

  6. Natural Poisson structures of nonlinear plasma dynamics

    International Nuclear Information System (INIS)

    Kaufman, A.N.

    1982-06-01

    Hamiltonian field theories, for models of nonlinear plasma dynamics, require a Poisson bracket structure for functionals of the field variables. These are presented, applied, and derived for several sets of field variables: coherent waves, incoherent waves, particle distributions, and multifluid electrodynamics. Parametric coupling of waves and plasma yields concise expressions for ponderomotive effects (in kinetic and fluid models) and for induced scattering

  7. Noncanonical Hamiltonian methods in plasma dynamics

    International Nuclear Information System (INIS)

    Kaufman, A.N.

    1981-11-01

    A Hamiltonian approach to plasma dynamics has numerous advantages over equivalent formulations which ignore the underlying Hamiltonian structure. In addition to achieving a deeper understanding of processes, Hamiltonian methods yield concise expressions (such as the Kubo form for linear susceptibility), greatly shorten the length of calculations, expose relationships (such as between the ponderomotive Hamiltonian and the linear susceptibility), determine invariants in terms of symmetry operations, and cover situations of great generality. In addition, they yield the Poincare invariants, in particular Liouville volume and adiabatic actions

  8. Isolated petrous apex ectopic craniopharyngioma

    Directory of Open Access Journals (Sweden)

    Julius July

    2015-12-01

    Full Text Available Primary ectopic craniopharyngioma is a rare entity. Isolated petrous apex bone location has not been reported previously. This study reports a case of 26-year-old male with right abducent nerve palsy. CT and MRI imaging reveal right petrous apex cystic lesion. No sellar or suprasellar region involvement was found. Endoscopic endonasal transphenoid approach has been successfully performed. Histopathology examination confirms the diagnosis of adamantinomatous craniopharyngioma. So far, it’s probably the first case report of primary ectopic craniopharyngioma isolated in the petrous apex. This case report supports the premise that primary ectopic craniopharyngioma is a multifactorial process that starts with an error from migrated embryological cells.

  9. Noncanonical Hamiltonian methods in plasma dynamics

    International Nuclear Information System (INIS)

    Kaufman, A.N.

    1982-01-01

    A Hamiltonian approach to plasma dynamics is described. The Poisson bracket of two observables g 1 and g 2 is given by using an antisymmetric tensor J, and must satisfy the Jacobi condition. The J can be obtained by elementary tensor analysis. The evolution in time of an observable g is given in terms of the Poisson bracket and a Hamiltonian H(Z). The guiding-center description of particle motion was presented by Littlejohn. The ponderomotive drift and force, the wave-induced oscillation-center velocity, and the gyrofrequency shift are obtained. The Lie transform yields the wave-induced increment to the gyromomentum. In the coulomb model for a Vlasov system, the dynamical variable is the Vlasov distribution f(z). The Hamiltonian functional and the Poisson bracket are obtained. The coupling of f(z) to the Maxwell field appears in the Poisson bracket. The evolution equation yields the Vlasov-Maxwell system. (Kato, T.)

  10. Submillimeter heterodyne arrays for APEX

    NARCIS (Netherlands)

    Güsten, R.; Baryshev, A.; Bell, A.; Belloche, A.; Graf, U.; Hafok, H.; Heyminck, S.; Hochgürtel, S.; Honingh, C. E.; Jacobs, K.; Kasemann, C.; Klein, B.; Klein, T.; Korn, A.; Krämer, I.; Leinz, C.; Lundgren, A.; Menten, K. M.; Meyer, K.; Muders, D.; Pacek, F.; Rabanus, D.; Schäfer, F.; Schilke, P.; Schneider, G.; Stutzki, J.; Wieching, G.; Wunsch, A.; Wyrowski, F.

    2008-01-01

    We report on developments of submillimeter heterodyne arrays for high resolution spectroscopy with APEX. Shortly, we will operate state-of-the-art instruments in all major atmospheric windows accessible from Llano de Chajnantor. CHAMP+, a dual-color 2×7 element heterodyne array for operation in the

  11. Oracle APEX 4.2 cookbook

    CERN Document Server

    Van Zoest, Michel

    2013-01-01

    As a Cookbook, this book enables you to create APEX web applications and to implement features with immediately usable recipes that unleash the powerful functionality of Oracle APEX 4.2. Each recipe is presented as a separate, standalone entity and the reading of other, prior recipes is not required.It can be seen as a reference and a practical guide to APEX development.This book is aimed both at developers new to the APEX environment and at intermediate developers. More advanced developers will also gain from the information at hand.If you are new to APEX you will find recipes to start develo

  12. Improvements to the APEX apparatus

    International Nuclear Information System (INIS)

    Ahmad, I.; Back, B.B.; Betts, R.R.

    1995-01-01

    A number of technical issues led us to rework extensively the APEX apparatus in summer 1994. During the earlier runs, a significant fraction of the 432 silicon detector elements showed degraded resolution such that they had to be excluded from the final analysis in software. The effect of this is to reduce the efficiency of APEX and possibly also to introduce holes in the acceptance which, for some perhaps exotic scenarios, might reduce the acceptance to an unacceptably low level. Also, the energy thresholds below which it is not possible to generate timing information from the silicon detectors, were high enough that the low-energy acceptance of APEX was compromised to a significant extent. The origins of these difficulties were in part due to degraded performance of the silicon detectors themselves, problems with the silicon cooling systems and electronics problems. Both silicon arrays were disassembled and sub-standard detectors replaced, all detectors were also cleaned with the result that all detectors now performed at the specified values of leakage current. The silicon cooling systems were disassembled and rebuilt with the result that many small leaks were fixed. Defective electronics channels were repaired or replaced. The rotating target wheel was also improved with the installation of new bearings and a computer-controlled rotation and readout system. The rebuilt wheel can now run at speeds up to 900 rpm for weeks on end without breakdown. The target wheel and associated beam sweeping now work extremely well so that low-melting-point targets such as Pb and In can be used in quite intense beams without melting

  13. Oracle Apex reporting tips and tricks

    CERN Document Server

    Bara, George

    2013-01-01

    Take advantage of all the exciting Reporting features of Oracle Application Express 4.2. Designed for a hands-on approach, this book contains in-depth practical guidelines from George Bara, a well-known Oracle Apex expert and blogger. From Classic to Interactive Reports, Web Services and Pdf Printing, "Oracle Apex Reporting Tips & Tricks" is a must-have for all database developers that want to make the most out of the Oracle Apex reporting engine.

  14. Oracle APEX 4.2 reporting

    CERN Document Server

    Pathak, Vishal

    2013-01-01

    Oracle APEX 4.2 Reporting is a practical tutorial for intermediate to advanced use, with plenty of step-by-step instructions and business scenarios for understanding and implementing the ins and outs of making reports.""Oracle APEX 4.2 Reporting"" is for you if you design or develop advanced solutions in APEX or wish to know about the advanced features of APEX. If you wish to have a 360 degree view of reporting technologies or work in a complex heterogeneous enterprise, this is a must-have.

  15. Lie-transformed action principle for classical plasma dynamics

    International Nuclear Information System (INIS)

    Kaufman, A.N.

    1984-06-01

    The Lie transform for a single particle in a wave is embedded in a Lagrangian action principle for self-consistent plasma dynamics. Variation of the action then yields the Vlasov equation for the oscillation-center distribution, the ray equations and amplitude transport for the wave, and the Poisson equation for the quasistatic field

  16. Regular and stochastic particle motion in plasma dynamics

    International Nuclear Information System (INIS)

    Kaufman, A.N.

    1979-08-01

    A Hamiltonian formalism is presented for the study of charged-particle trajectories in the self-consistent field of the particles. The intention is to develop a general approach to plasma dynamics. Transformations of phase-space variables are used to separate out the regular, adiabatic motion from the irregular, stochastic trajectories. Several new techniques are included in this presentation

  17. Petrous apex lesions in the pediatric population

    Energy Technology Data Exchange (ETDEWEB)

    Radhakrishnan, Rupa [University of Cincinnati College of Medicine, Department of Radiology, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Son, Hwa Jung [University of Cincinnati College of Medicine, Department of Otolaryngology-Head and Neck Surgery, Cincinnati, OH (United States); Koch, Bernadette L. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2014-03-15

    A variety of abnormal imaging findings of the petrous apex are encountered in children. Many petrous apex lesions are identified incidentally while images of the brain or head and neck are being obtained for indications unrelated to the temporal bone. Differential considerations of petrous apex lesions in children include ''leave me alone'' lesions, infectious or inflammatory lesions, fibro-osseous lesions, neoplasms and neoplasm-like lesions, as well as a few rare miscellaneous conditions. Some lesions are similar to those encountered in adults, and some are unique to children. Langerhans cell histiocytosis (LCH) and primary and metastatic pediatric malignancies such as neuroblastoma, rhabomyosarcoma and Ewing sarcoma are more likely to be encountered in children. Lesions such as petrous apex cholesterol granuloma, cholesteatoma and chondrosarcoma are more common in adults and are rarely a diagnostic consideration in children. We present a comprehensive pictorial review of CT and MRI appearances of pediatric petrous apex lesions. (orig.)

  18. [Electronic Apex Locator as a dental instrument].

    Science.gov (United States)

    Lin, S; Winocur-Arias, O; Slutzky-Goldberg, I

    2009-04-01

    Electronic Apex Locators (EAL) have become widely used in the last decade. The first apex locator was introduced in 1962, based on a constant electrical resistance (6.5 K.) between the oral mucosa and periodontal ligament. The first and second generations of EAL were inaccurate and could not detect the apex in the presence of conducting fluids. The third generation solved this problem by using two alternating frequencies and calculating the impedance between them. This provided reliable and accurate results in dry canals, or in the presence of blood, electrolytes or other fluid in the root canals, when the pulp was necrotic or when there was a perforation along the root. The Root ZX and Apit (Endex) are the most documented devices. The new fourth generation of apex locators is a diverse group: some use multifrequency currents, others use a "lookup matrix" rather than calculate the readings. Several of the newer EALs are smaller, and others connect to computers.

  19. Apex Predators Program Age and Growth Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Apex Predators Program staff have collected vertebral centra from sportfishing tournaments, cruises, commercial fishermen and strandings in the Northeast US since...

  20. Apex Predators Program Sportfishing Tournament Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Apex Predators Program staff have collected shark sportfishing tournamant data from the Northeast US since the 1960's. These tournaments offer a unique opportunity...

  1. CHAMP+ : A powerful array receiver for APEX

    NARCIS (Netherlands)

    Kasemann, C.; Güsten, R.; Heyminck, S.; Klein, B.; Klein, T.; Philipp, S.D.; Korn, A.; Schneider, G.; Henseler, A.; Baryshev, A.; Klapwijk, T.M.

    2006-01-01

    CHAMP+, a dual-color 2 × 7 element heterodyne array for operation in the 450 ?m and 350 ?m atmospheric windows is under development. The instrument, which is currently undergoing final evaluation in the laboratories, will be deployed for commissioning at the APEX telescope in August this year. With

  2. CHAMP + : A powerful array receiver for APEX

    NARCIS (Netherlands)

    Kasemann, C.; Güsten, R.; Heyminck, S.; Klein, B.; Klein, T.; Philipp, S. D.; Korn, A.; Schneider, G.; Henseler, A.; Baryshev, A.; Klapwijk, T. M.

    2006-01-01

    CHAMP +, a dual-color 2 × 7 element heterodyne array for operation in the 450 μm and 350 μm atmospheric windows is under development. The instrument, which is currently undergoing final evaluation in the laboratories, will be deployed for commissioning at the APEX telescope in August this year. With

  3. Petrous apex chordoma - a case report

    International Nuclear Information System (INIS)

    Silveira, Claudio Regis S.; Barreto, Cristina Marques; Rossi, Luis Antonio; Michiloski, Custodio; Rotta, Jose Marcus; Almeida, Serguey Malaquias de

    2001-01-01

    Chordomas are rare neoplasms arising from notochordal remnants that persist along the axial skeleton. Intracranial chordomas occur more frequently in the midline. We describe a typical case of an off-midline chordoma arising from the petrous apex, and discuss the embryogenic factors which determine that location, as well as the symptoms, imaging findings, surgical treatment and evolution. (author)

  4. Petrous apex lesions outcome in 21 cases

    Directory of Open Access Journals (Sweden)

    Hekmatara M

    1997-09-01

    Full Text Available Petrous apex lesions of temporal bone progress slowly. Most of the time not only destruct this area but also involve neighbouring element. The symptoms of the neighbouring neuro-vasculare involvement we can recognize these lesions. The most common symptoms of involvement of the petrous apex are: headache, conductive hearing loss or sensorineural type, paresthesia and anesthesia of the trigeminal nerve, paresia and paralysis of the facial nerve, abducent nerve. In retrospective study which has been in the ENT and HNS wards of Amiralam hospital, 148 patients have been operated due to temporal bone tumor; from these numbers, 21 (13.6% patients had petrous apex lesions of temporal bone. Eleven (52.9% patients of these 21 persons were men and the remaining 10 (47-6% were women. The average age of the patients was 37 years. The common pathology of these patients were glomus jugulare tumors, hemangioma, schwannoma, meningioma, congenital cholesteatoma, giant cell granuloma. The kind of operations that have been done on these patients were: infratemporal, translabyrinthine and middle fossa approaches. The conclusion of this study shows that petrous apex area is an occult site. The symptoms of this lesion are not characteristic, meticulous attention to the history and physical examination are very helpful to recognition of these lesions and it's extention.

  5. Accuracy of working length determination with root ZX apex locator ...

    African Journals Online (AJOL)

    Jane

    2011-07-18

    Jul 18, 2011 ... generation of electronic apex locators (EALs), called root. ZX (J. Morita Co., Tustin, .... dentinocemento junction. Dent Items Interest, 50: 855-857. ... apex locator with an automatic compensation circuit. J. Endod. 28: 706-709.

  6. Relationship between age and location of the apex beat among ...

    African Journals Online (AJOL)

    Location of apex beat is an integral part of routine cardiovascular system examination in clinical practice. However, there is paucity of ... Apex beat location in the intercostal space was determined and distance of apex beat from the midline, midclavicular line and nipple lines were measured. The measured distances were ...

  7. Targets for the APEX experiment at ATLAS

    International Nuclear Information System (INIS)

    Greene, J.P.; Thomas, G.E.; Leonard, R.H.

    1994-01-01

    Targets of lead, tantalum, thorium and uranium have been produced for experiments with the APEX (Argonne Positron Experiment) apparatus at ATLAS (Argonne Tandem Linac Accelerator System). APEX is a device built at Argonne National Laboratory to investigate the anomalous positrons observed in collisions of very heavy ion beams on heavy targets. Both fixed and rotating targets have been used. The rotating target system involves a 4-quadrant wheel rotating at speeds up to 700 rpm with the position encoded into the data stream. In addition to the hundreds of targets produced for the heavy-ion reactions studied, a wide variety of targets were employed for beam diagnostics, detector calibration and target wheel development. The experiment used very heavy ion beams ( 238 U, 206 Pb and 208 Pb) from ATLAS and targets of 206 Pb, 208 Pb, 232 Th and 238 U produced in the laboratory

  8. Image guided surgery for petrous apex lesions

    International Nuclear Information System (INIS)

    Van Havenbergh, T.; De Ridder, D.; Verlooy, J.; Koekelkoren, E.; Van De Heyning, P.

    2003-01-01

    To evaluate whether computer-assisted frameless stereotactic navigation in the temporal bone provides sufficient clinical application accuracy and thus a useful tool in temporal bone surgery. Two patients with petrous apex cholesterol granuloma were operated on by an epidural middle fossa approach using a Stealth/MedtronicTM neuronavigation system. Based an literature data optimal skin fiducial placement and registration methods were used. Intra-operative accuracy was checked using three precise anatomical landmarks. Drilling of the petrotis apex bone was guided by neuronavigation. Postoperative Computed Tomography (CT) images were fused with the preoperative CT and planning. The application of image-guidance in temporal bone surgery causes no additional burden to the patient nor prolongs the operating time. The accuracy measured at the anatomical landmarks was under 2,0 mm. This is confirmed by evaluation of bone removal through image fusion of pre- and postoperative CT scan. The clinical application of a neuronavigation system during petrous apex surgery can be regarded as useful. Using all available data on registration methods it seems possible to obtain intra-operative application accuracies of < 2,0 mm. Additional cadaver work is being performed to support these data. (author)

  9. Electron density and plasma dynamics of a colliding plasma experiment

    Energy Technology Data Exchange (ETDEWEB)

    Wiechula, J., E-mail: wiechula@physik.uni-frankfurt.de; Schönlein, A.; Iberler, M.; Hock, C.; Manegold, T.; Bohlender, B.; Jacoby, J. [Plasma Physics Group, Institute of Applied Physics, Goethe University, 60438 Frankfurt am Main (Germany)

    2016-07-15

    We present experimental results of two head-on colliding plasma sheaths accelerated by pulsed-power-driven coaxial plasma accelerators. The measurements have been performed in a small vacuum chamber with a neutral-gas prefill of ArH{sub 2} at gas pressures between 17 Pa and 400 Pa and load voltages between 4 kV and 9 kV. As the plasma sheaths collide, the electron density is significantly increased. The electron density reaches maximum values of ≈8 ⋅ 10{sup 15} cm{sup −3} for a single accelerated plasma and a maximum value of ≈2.6 ⋅ 10{sup 16} cm{sup −3} for the plasma collision. Overall a raise of the plasma density by a factor of 1.3 to 3.8 has been achieved. A scaling behavior has been derived from the values of the electron density which shows a disproportionately high increase of the electron density of the collisional case for higher applied voltages in comparison to a single accelerated plasma. Sequences of the plasma collision have been taken, using a fast framing camera to study the plasma dynamics. These sequences indicate a maximum collision velocity of 34 km/s.

  10. Neurothekeoma of petrous apex: A rare entity

    Directory of Open Access Journals (Sweden)

    Zarina Abdul Assis

    2013-01-01

    Full Text Available Intraosseous nerve sheath tumors are very rare tumors accounting for lesser than 0.2% of primary bone tumors. We present an 18-year-old female who presented with left facial paresis for the last 1 year. Magnetic resonance imaging (MRI demonstrated expansile, multiseptated, enhancing bony lesion in the left petrous apex. There was also abnormal enhancement of the 7-8 th nerve complex within the internal auditory canal. Tumor was excised by subtemporal extradural approach. The lesion was diagnosed as intraosseous neurothekeoma on histopathology. This is an extremely rare tumor and its MRI appearance in this location is being described for the first time in literature.

  11. PIXEL ANALYSIS OF PHOTOSPHERIC SPECTRAL DATA. I. PLASMA DYNAMICS

    Energy Technology Data Exchange (ETDEWEB)

    Rasca, Anthony P.; Chen, James [Plasma Physics Division, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Pevtsov, Alexei A., E-mail: anthony.rasca.ctr@nrl.navy.mil [National Solar Observatory, Sunspot, NM 88349 (United States)

    2016-11-20

    Recent observations of the photosphere using high spatial and temporal resolution show small dynamic features at or below the current resolving limits. A new pixel dynamics method has been developed to analyze spectral profiles and quantify changes in line displacement, width, asymmetry, and peakedness of photospheric absorption lines. The algorithm evaluates variations of line profile properties in each pixel and determines the statistics of such fluctuations averaged over all pixels in a given region. The method has been used to derive statistical characteristics of pixel fluctuations in observed quiet-Sun regions, an active region with no eruption, and an active region with an ongoing eruption. Using Stokes I images from the Vector Spectromagnetograph (VSM) of the Synoptic Optical Long-term Investigations of the Sun (SOLIS) telescope on 2012 March 13, variations in line width and peakedness of Fe i 6301.5 Å are shown to have a distinct spatial and temporal relationship with an M7.9 X-ray flare in NOAA 11429. This relationship is observed as stationary and contiguous patches of pixels adjacent to a sunspot exhibiting intense flattening in the line profile and line-center displacement as the X-ray flare approaches peak intensity, which is not present in area scans of the non-eruptive active region. The analysis of pixel dynamics allows one to extract quantitative information on differences in plasma dynamics on sub-pixel scales in these photospheric regions. The analysis can be extended to include the Stokes parameters and study signatures of vector components of magnetic fields and coupled plasma properties.

  12. University of Maryland component of the Center for Multiscale Plasma Dynamics: Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Dorland, William [University of Maryland

    2014-11-18

    The Center for Multiscale Plasma Dynamics (CMPD) was a five-year Fusion Science Center. The University of Maryland (UMD) and UCLA were the host universities. This final technical report describes the physics results from the UMD CMPD.

  13. An in-house manual for building APEX projects using ArcAPEX

    Science.gov (United States)

    The Agricultural Policy Environmental eXtender (APEX) provides the foundation for water quality and natural resource analysis across a wide array of USDA initiatives, projects and programs. The model has been utilized in both the national Conservation Effects Assessment Project (CEAP) analysis and ...

  14. Geometric correction of APEX hyperspectral data

    Directory of Open Access Journals (Sweden)

    Vreys Kristin

    2016-03-01

    Full Text Available Hyperspectral imagery originating from airborne sensors is nowadays widely used for the detailed characterization of land surface. The correct mapping of the pixel positions to ground locations largely contributes to the success of the applications. Accurate geometric correction, also referred to as “orthorectification”, is thus an important prerequisite which must be performed prior to using airborne imagery for evaluations like change detection, or mapping or overlaying the imagery with existing data sets or maps. A so-called “ortho-image” provides an accurate representation of the earth’s surface, having been adjusted for lens distortions, camera tilt and topographic relief. In this paper, we describe the different steps in the geometric correction process of APEX hyperspectral data, as applied in the Central Data Processing Center (CDPC at the Flemish Institute for Technological Research (VITO, Mol, Belgium. APEX ortho-images are generated through direct georeferencing of the raw images, thereby making use of sensor interior and exterior orientation data, boresight calibration data and elevation data. They can be referenced to any userspecified output projection system and can be resampled to any output pixel size.

  15. The Pleiades apex and its kinematical structure

    Science.gov (United States)

    Elsanhoury, W. H.; Postnikova, E. S.; Chupina, N. V.; Vereshchagin, S. V.; Sariya, Devesh P.; Yadav, R. K. S.; Jiang, Ing-Guey

    2018-03-01

    A study of cluster characteristics and internal kinematical structure of the middle-aged Pleiades open star cluster is presented. The individual star apexes and various cluster kinematical parameters including the velocity ellipsoid parameters are determined using both Hipparcos and Gaia data. Modern astrometric parameters were taken from the Gaia Data Release 1 (DR1) in combination with the Radial Velocity Experiment Fifth Data Release (DR5). The necessary set of parameters including parallaxes, proper motions and radial velocities are used for n=17 stars from Gaia DR1+RAVE DR5 and for n=19 stars from the Hipparcos catalog using SIMBAD data base. Single stars are used to improve accuracy by eliminating orbital movements. RAVE DR5 measurements were taken only for the stars with the radial velocity errors not exceeding 2 km/s. For the Pleiades stars taken from Gaia, we found mean heliocentric distance as 136.8 ± 6.4 pc, and the apex position is calculated as: A_{CP}=92°.52± 1°.72, D_{CP}=-42°.28± 2°.56 by the convergent point method and A0=95°.59± 2°.30 and D0=-50°.90± 2°.04 using AD-diagram method (n=17 in both cases). The results are compared with those obtained historically before the Gaia mission era.

  16. APEX - the Hyperspectral ESA Airborne Prism Experiment

    Directory of Open Access Journals (Sweden)

    Koen Meuleman

    2008-10-01

    Full Text Available The airborne ESA-APEX (Airborne Prism Experiment hyperspectral mission simulator is described with its distinct specifications to provide high quality remote sensing data. The concept of an automatic calibration, performed in the Calibration Home Base (CHB by using the Control Test Master (CTM, the In-Flight Calibration facility (IFC, quality flagging (QF and specific processing in a dedicated Processing and Archiving Facility (PAF, and vicarious calibration experiments are presented. A preview on major applications and the corresponding development efforts to provide scientific data products up to level 2/3 to the user is presented for limnology, vegetation, aerosols, general classification routines and rapid mapping tasks. BRDF (Bidirectional Reflectance Distribution Function issues are discussed and the spectral database SPECCHIO (Spectral Input/Output introduced. The optical performance as well as the dedicated software utilities make APEX a state-of-the-art hyperspectral sensor, capable of (a satisfying the needs of several research communities and (b helping the understanding of the Earth’s complex mechanisms.

  17. Cholesterol granuloma of the petrous apex: CT diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Lo, W.W.M.; Solti-Bohman, L.G.; Brackmann, D.E.; Gruskin, P.

    1984-12-01

    Cholesterol granuloma of the petrous apex is a readily recognizable and treatable entity that is more common than previously realized. Cholesterol granuloma grows slowly in the petrous apex as a mass lesion until it produces hearing loss, tinnitus, vertigo, and facial twitching. Twelve cases of cholesterol granuloma of the petrous apex are illustrated; ten of these analyzed in detail, especially with respect to CT findings. A sharply and smoothly marginated expansile lesion in the petrous apex, isodense with plain and nonenhancing on CT, is in all probability a cholesterol granuloma. Preoperative recognition by CT is important for planning proper treatment.

  18. Cholesterol granuloma of the petrous apex: CT diagnosis

    International Nuclear Information System (INIS)

    Lo, W.W.M.; Solti-Bohman, L.G.; Brackmann, D.E.; Gruskin, P.

    1984-01-01

    Cholesterol granuloma of the petrous apex is a readily recognizable and treatable entity that is more common than previously realized. Cholesterol granuloma grows slowly in the petrous apex as a mass lesion until it produces hearing loss, tinnitus, vertigo, and facial twitching. Twelve cases of cholesterol granuloma of the petrous apex are illustrated; ten of these analyzed in detail, especially with respect to CT findings. A sharply and smoothly marginated expansile lesion in the petrous apex, isodense with plain and nonenhancing on CT, is in all probability a cholesterol granuloma. Preoperative recognition by CT is important for planning proper treatment

  19. Transverse Space-Charge Field-Induced Plasma Dynamics for Ultraintense Electron-Beam Characterization

    Directory of Open Access Journals (Sweden)

    R. Tarkeshian

    2018-05-01

    Full Text Available Similarly to laser or x-ray beams, the interaction of sufficiently intense particle beams with neutral gases will result in the creation of plasma. In contrast to photon-based ionization, the strong unipolar field of a particle beam can generate a plasma where the electron population receives a large initial momentum kick and escapes, leaving behind unshielded ions. Measuring the properties of the ensuing Coulomb exploding ions—such as their kinetic energy distribution, yield, and spatial distribution—can provide information about the peak electric fields that are achieved in the electron beams. Particle-in-cell simulations and analytical models are presented for high-brightness electron beams of a few femtoseconds or even hundreds of attoseconds, and transverse beam sizes on the micron scale, as generated by today’s free electron lasers. Different density regimes for the utilization as a potential diagnostics are explored, and the fundamental differences in plasma dynamical behavior for e-beam or photon-based ionization are highlighted. By measuring the dynamics of field-induced ions for different gas and beam densities, a lower bound on the beam charge density can be obtained in a single shot and in a noninvasive way. The exponential dependency of the ionization yield on the beam properties can provide unprecedented spatial and temporal resolution, at the submicrometer and subfemtosecond scales, respectively, offering a practical and powerful approach to characterizing beams from accelerators at the frontiers of performance.

  20. Plasma dynamics in aluminium wire array Z-pinch implosions

    International Nuclear Information System (INIS)

    Bland, S.N.

    2001-01-01

    The wire array Z-pinch is the world's most powerful laboratory X-ray source. An achieved power of ∼280TW has generated great interest in the use of these devices as a source of hohlraum heating for inertial confinement fusion experiments. However, the physics underlying how wire array Z-pinches implode is not well understood. This thesis presents the first detailed measurements of plasma dynamics in wire array experiments. The MAGPIE generator, with currents of up to 1.4MA, 150ns 10-90% rise-time, was used to implode arrays of 16mm diameter typically containing between 8 and 64 15μm aluminium wires. Diagnostics included: end and side-on laser probing with interferometry, schlieren and shadowgraphy channels; radial and axial streak photography; gated X-ray imaging; XUV and hard X-ray spectrometry; filtered XRDs and diamond PCDs; and a novel X-ray backlighting system to probe high density plasma. It was found that the plasma formed from the wires consisted of cold, dense cores, which ablated producing hot, low density coronal plasma. After an initial acceleration around the cores, coronal plasma streams flowed force-free towards the axis, with an instability wavelength determined by the core size. At ∼50% of the implosion time, the streams collided on axis forming a precursor plasma which appeared to be uniform, stable, and inertially confined. The existence of core-corona structure significantly affected implosion dynamics. For arrays with <64 wires, the wire cores remained in their original positions until ∼80% of the implosion time before accelerating rapidly. At 64 wires a transition in implosion trajectories to 0-D like occurred indicating a possible merger of current carrying plasma close to the cores - the cores themselves did not merge. During implosion, the cores initially developed uncorrelated instabilities that then transformed into a longer wavelength global mode of instability. The study of nested arrays (2 concentric arrays, one inside the other

  1. Atmospheric correction of APEX hyperspectral data

    Directory of Open Access Journals (Sweden)

    Sterckx Sindy

    2016-03-01

    Full Text Available Atmospheric correction plays a crucial role among the processing steps applied to remotely sensed hyperspectral data. Atmospheric correction comprises a group of procedures needed to remove atmospheric effects from observed spectra, i.e. the transformation from at-sensor radiances to at-surface radiances or reflectances. In this paper we present the different steps in the atmospheric correction process for APEX hyperspectral data as applied by the Central Data Processing Center (CDPC at the Flemish Institute for Technological Research (VITO, Mol, Belgium. The MODerate resolution atmospheric TRANsmission program (MODTRAN is used to determine the source of radiation and for applying the actual atmospheric correction. As part of the overall correction process, supporting algorithms are provided in order to derive MODTRAN configuration parameters and to account for specific effects, e.g. correction for adjacency effects, haze and shadow correction, and topographic BRDF correction. The methods and theory underlying these corrections and an example of an application are presented.

  2. Towards Accurate Application Characterization for Exascale (APEX)

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, Simon David [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Sandia National Laboratories has been engaged in hardware and software codesign activities for a number of years, indeed, it might be argued that prototyping of clusters as far back as the CPLANT machines and many large capability resources including ASCI Red and RedStorm were examples of codesigned solutions. As the research supporting our codesign activities has moved closer to investigating on-node runtime behavior a nature hunger has grown for detailed analysis of both hardware and algorithm performance from the perspective of low-level operations. The Application Characterization for Exascale (APEX) LDRD was a project concieved of addressing some of these concerns. Primarily the research was to intended to focus on generating accurate and reproducible low-level performance metrics using tools that could scale to production-class code bases. Along side this research was an advocacy and analysis role associated with evaluating tools for production use, working with leading industry vendors to develop and refine solutions required by our code teams and to directly engage with production code developers to form a context for the application analysis and a bridge to the research community within Sandia. On each of these accounts significant progress has been made, particularly, as this report will cover, in the low-level analysis of operations for important classes of algorithms. This report summarizes the development of a collection of tools under the APEX research program and leaves to other SAND and L2 milestone reports the description of codesign progress with Sandia’s production users/developers.

  3. Localization of the prostatic apex for radiation treatment planning

    International Nuclear Information System (INIS)

    Algan, Oezer; Hanks, Gerald E.; Shaer, Andrew H.

    1995-01-01

    Purpose: To determine whether retrograde urethrogram, or the combination of computed tomography (CT) scan/retrograde urethrogram is more accurate for locating the magnetic resonance imaging (MRI) designated prostatic apex, and to determine whether patients treated in our department with CT/urethrogram are receiving the prescribed minimal dose to the MRI identified prostatic apex. Methods and Materials: Seventeen patients with early stage prostate cancer were enrolled in a prospective study to determine the location of the prostatic apex. All of the patients agreed to undergo MRI in addition to retrograde urethrogram, and CT of the pelvis for three dimensional (3D) treatment planning. The prostatic apex was identified on each of the studies and measured from a reference point (the most superior portion of the pubic symphysis). The location of the prostatic apex as measured by retrograde urethrogram alone and by CT/urethrogram was compared to the location of the prostatic apex as measured by MRI. Because of MRI's ability for multiplanar capabilities, and high soft tissue contrast in the region of the prostate, it was assumed to be more accurate for identifying the location of the prostatic apex, and was used as the gold standard. Results: The location of the prostatic apex as determined by the urethrogram alone was on average 5.8 mm caudad to the location on MRI (p = 0.012), while the location of the prostatic apex as determined by CT/urethrogram was 3.1 mm caudad to the location on MRI (p = 0.150). If the prostatic apex is defined at 12 mm instead of 10 mm above the urethrogram tip, the statistically significant difference between the urethrogram and the MRI is no longer present. Based on these results, all 17 patients received the minimum prescribed dose to the prostatic apex. Conclusion: CT/urethrogram correlates better with the location of the MRI determined prostatic apex, than does the urethrogram alone. Locating the prostatic apex 12 mm above the urethrogram

  4. Electronics for the Si detectors in APEX

    International Nuclear Information System (INIS)

    Wilt, P.R.; Betts, R.R.; Freer, M.

    1994-01-01

    APEX (ATLAS Positron EXperiment), a collaborative effort of ANL, FSU, MSU/NSCL, Princeton, Queen's, Rochester, Washington and Yale, is an experiment to study positron and electron production in very heavy ion collisions. The electrons and positrons are detected with two detector arrays, each consisting of 216 1 mm thick Si PIN diodes, and their energy and time-of-flight are measured. The number of detectors and limited space made it necessary to develop a system that could efficiently process and transfer signals from the detectors to the charge sensing ADC's and data readout electronics as well as monitor the condition of the detectors. The discussion will cover the electronics designed for the Si detectors, including the charge amplifier, ''Mother board'' for the charge amplifiers, 8 channel Shaper, 16 channel Constant Fraction Discriminator (CFD), 16 channel Peak-to-FERA (PTF) and the integration of the CFD and PTF with Charge sensing ADC's. Function and performance of the individual modules as well as the system as a whole will be discussed

  5. Metastatic neuroendocrine tumor with initial presentation of orbital apex syndrome

    Directory of Open Access Journals (Sweden)

    Yen-Yu Huang

    2017-03-01

    Full Text Available The possible etiologies of orbital apex syndrome range from inflammatory, infectious, neoplastic, iatrogenic/traumatic, to vascular processes. In patients without obvious infection or systemic cancer history, judicious use of corticosteroids is a reasonable strategy. We describe a 64-year-old man who presented with orbital apex syndrome and had progressed to total visual loss in three days after admission. Radiological imaging and pathological studies were consistent with a neuroendocrine tumor with multiple metastases. We recommend that a biopsy-proven specimen is warranted in patient with orbital apex syndrome even without a cancer history.

  6. Resection of the Tooth Apex with Diode Laser

    Directory of Open Access Journals (Sweden)

    Uzunov Tz.

    2014-06-01

    Full Text Available An “in vitro” experimental study has been carried out on 70 extracted teeth. A laser resection of the root apex has been carried out with diode laser beam with a wavelength of - 810 ± 10 nm. Sequentially a radiation with increasing power has been applied, as follows: 1,3 W, 2W, 3W, 4W, 5W, 6W, 7W, in electro surgery mode. Successful resection of the tooth apex has been performed at: 3W; 4W; 5W; 6W and 7W power. It was established that when laser resected the tooth apex carbonizes.

  7. Localization of the prostatic apex for radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Wilder, Richard B.; Fone, Patricia D.; Jones, C. Darryl; White, Ralph DeVere

    1996-01-01

    Purpose/Objective: There is no consensus on the optimal method for localizing the prostatic apex in patients with early stage adenocarcinoma of the prostate. Some radiation oncologists have recommended that transrectal ultrasound or MRI scans be used to define the inferior border of radiation portals. The purpose of this prospective study is to assess the ability of retrograde urethrograms and CT scans to accurately define the prostatic apex in the craniocaudad dimension, using urethroscopy as a reference. Materials and Methods: Following construction of an Alpha cradle, plain radiographs of the pelvis were obtained in 15 patients with early stage adenocarcinoma of the prostate, with the tip of a urethroscope placed at the superior border of the external sphincter (which most closely approximates the prostatic apex). The scope was then withdrawn, and a retrograde urethrogram was performed. Immediately afterwards, a treatment planning CT scan of the pelvis was obtained. Since differential filling of the bladder and rectum affects the position of the prostatic apex, patients voided prior to rather than in between the 3 consecutive studies. Results: The urethroscopy-defined prostatic apex was located 28 ± 3 mm (mean ± SE) superior to the ischial tuberosities, 12 ± 1 mm (mean ± SE) superior to the urethrogram tip and 8 ± 2 mm (mean ± SE) superior to the CT-defined apex. Placement of the inferior border of the radiation portals at the ischial tuberosities would have resulted in irradiation of > 20 mm membranous and spongy urethra in all of the patients. Conclusion: Retrograde urethrograms provide more helpful information than CT scans with regard to localization of the prostatic apex and are more cost effective than sonograms or MRI scans. The prostatic apex is typically 12 mm superior to the urethrogram tip with little variability. Retrograde urethrograms allow one to spare as much urethra as possible in the radiation portals, which should theoretically reduce

  8. Information on the Advanced Plant Experiment (APEX) Test Facility

    International Nuclear Information System (INIS)

    Smith, Curtis Lee

    2015-01-01

    The purpose of this report provides information related to the design of the Oregon State University Advanced Plant Experiment (APEX) test facility. Information provided in this report have been pulled from the following information sources: Reference 1: R. Nourgaliev and et.al, 'Summary Report on NGSAC (Next-Generation Safety Analysis Code) Development and Testing,' Idaho National Laboratory, 2011. Note that this is report has not been released as an external report. Reference 2: O. Stevens, Characterization of the Advanced Plant Experiment (APEX) Passive Residual Heat Removal System Heat Exchanger, Master Thesis, June 1996. Reference 3: J. Reyes, Jr., Q. Wu, and J. King, Jr., Scaling Assessment for the Design of the OSU APEX-1000 Test Facility, OSU-APEX-03001 (Rev. 0), May 2003. Reference 4: J. Reyes et al, Final Report of the NRC AP600 Research Conducted at Oregon State University, NUREG/CR-6641, July 1999. Reference 5: K. Welter et al, APEX-1000 Confirmatory Testing to Support AP1000 Design Certification (non-proprietary), NUREG-1826, August 2005.

  9. Scaling analysis for the OSU AP600 test facility (APEX)

    International Nuclear Information System (INIS)

    Reyes, J.N.

    1998-01-01

    In this paper, the authors summarize the key aspects of a state-of-the-art scaling analysis (Reyes et al. (1995)) performed to establish the facility design and test conditions for the advanced plant experiment (APEX) at Oregon State University (OSU). This scaling analysis represents the first, and most comprehensive, application of the hierarchical two-tiered scaling (H2TS) methodology (Zuber (1991)) in the design of an integral system test facility. The APEX test facility, designed and constructed on the basis of this scaling analysis, is the most accurate geometric representation of a Westinghouse AP600 nuclear steam supply system. The OSU APEX test facility has served to develop an essential component of the integral system database used to assess the AP600 thermal hydraulic safety analysis computer codes. (orig.)

  10. Orbital apex syndrome associated with herpes zoster ophthalmicus

    Directory of Open Access Journals (Sweden)

    Kurimoto T

    2011-11-01

    Full Text Available Takuji Kurimoto1, Masahiro Tonari1, Norihiko Ishizaki1, Mitsuhiro Monta2, Saori Hirata2, Hidehiro Oku1, Jun Sugasawa1, Tsunehiko Ikeda11Department of Ophthalmology, Osaka Medical College, 2Department of Ophthalmology, Shitennoji Hospital, Osaka, JapanAbstract: We report our findings for a patient with orbital apex syndrome associated with herpes zoster ophthalmicus. Our patient was initially admitted to a neighborhood hospital because of nausea and loss of appetite of 10 days' duration. The day after hospitalization, she developed skin vesicles along the first division of the trigeminal nerve, with severe lid swelling and conjunctival injection. On suspicion of meningoencephalitis caused by varicella zoster virus, antiviral therapy with vidarabine and betamethasone was started. Seventeen days later, complete ptosis and ophthalmoplegia developed in the right eye. The light reflex in the right eye was absent and anisocoria was present, with the right pupil larger than the left. Fat-suppressed enhanced T1-weighted magnetic resonance images showed high intensity areas in the muscle cone, cavernous sinus, and orbital optic nerve sheath. Our patient was diagnosed with orbital apex syndrome, and because of skin vesicles in the first division of the trigeminal nerve, the orbital apex syndrome was considered to be caused by herpes zoster ophthalmicus. After the patient was transferred to our hospital, prednisolone 60 mg and vidarabine antiviral therapy was started, and fever and headaches disappeared five days later. The ophthalmoplegia and optic neuritis, but not the anisocoria, gradually resolved during tapering of oral therapy. From the clinical findings and course, the cause of the orbital apex syndrome was most likely invasion of the orbital apex and cavernous sinus by the herpes virus through the trigeminal nerve ganglia.Keywords: varicella zoster virus, orbital apex syndrome, herpes zoster ophthalmicus, complete ophthalmoplegia

  11. Exploration

    International Nuclear Information System (INIS)

    Lohrenz, J.

    1992-01-01

    Oil and gas exploration is a unique kind of business. Businesses providing a vast and ever-changing panoply of products to markets are a focus of several disciplines' energetic study and analysis. The product inventory problem is robust, pertinent, and meaningful, and it merits the voluminous and protracted attention received from keen business practitioners. Prototypical business practitioners, be they trained by years of business hurly-burly, or sophisticated MBAs with arrays of mathematical algorithms and computers, are not normally prepared, however, to recognize the unique nature of exploration's inventories. Put together such a business practitioner with an explorationist and misunderstandings, hidden and open, are inevitable and predictably rife. The first purpose of this paper is to articulate the inherited inventory handling paradigms of business practitioners in relation to exploration's inventories. To do so, standard pedagogy in business administration is used and a case study of an exploration venture is presented. A second purpose is to show the burdens that the misunderstandings create. The result is not just business plans that go awry, but public policies that have effects opposite from those intended

  12. In vitro comparison of four different electronic apex locators to ...

    African Journals Online (AJOL)

    2014-04-14

    Apr 14, 2014 ... Materials and Methods: Forty-eight extracted single-rooted extracted teeth with ... increase postoperative pain and delay or prevent healing.[4] ... market to locate the root apex for measuring the WL such ... was used to check the canal patency. ... manufacturer's instructions for detecting the major foramen.

  13. Endoscopic transsphenoidal surgery for cholesterol granulomas involving the petrous apex

    NARCIS (Netherlands)

    Georgalas, C.; Kania, R.; Guichard, J.-P.; Sauvaget, E.; Tran Ba Huy, P.; Herman, P.

    2008-01-01

    Surgery for cholesterol granulomas involving the petrous apex has traditionally been performed via a lateral skull base approach. We present a case-series of four cholesterol granulomas treated through the endoscopic-transsphenoid approach over the last 10 years. Drainage was successful and

  14. Endoscopic trans-sphenoidal drainage of petrous apex cholesterol ...

    African Journals Online (AJOL)

    Cholesterol granulomas of the petrous apex are rare lesions that pose challenging surgical decisions and approaches when attempting surgical drainage. In this article we present 2 cases of successful surgical management using an endoscopic trans-sphenoidal approach and review the requirements and considerations ...

  15. Comparison of various current electronic apex locators to determine ...

    African Journals Online (AJOL)

    Objective: The objective was to compare in vitro the accuracy of three electronic apex locators (EALs) (DentaPort ZX [Morita Co., Tokyo, Japan], SIROEndo Pocket [Sirona Dental Systems, ... All teeth were embedded in an alginate model, and the electronic measurements were taken following the manufacturers' orientations.

  16. APEX (Air Pollution Exercise) Volume 20: Reference Materials.

    Science.gov (United States)

    Environmental Protection Agency, Research Triangle Park, NC. Office of Manpower Development.

    The Reference Materials Manual is part of a set of 21 manuals (AA 001 009-001 029) used in APEX (Air Pollution Exercise), a computerized college and professional level "real world" game simulation of a community with urban and rural problems, industrial activities, and air pollution difficulties. For the purposes of the gaming exercise, APEX…

  17. Accuracy of working length determination with root ZX apex locator ...

    African Journals Online (AJOL)

    The purpose of this study was to clinically compare working length (WL) determination with root ZX apex locator and radiography, and then compare them with direct visualization method ex vivo. A total of 75 maxillary central and lateral incisors were selected. Working length determination was carried out using radiographic ...

  18. Do neonatal mouse hearts regenerate following heart apex resection?

    DEFF Research Database (Denmark)

    Andersen, Ditte Caroline; Ganesalingam, Suganya; Jensen, Charlotte Harken

    2014-01-01

    The mammalian heart has generally been considered nonregenerative, but recent progress suggests that neonatal mouse hearts have a genuine capacity to regenerate following apex resection (AR). However, in this study, we performed AR or sham surgery on 400 neonatal mice from inbred and outbred...

  19. Phosphorus modeling in tile drained agricultural systems using APEX

    Science.gov (United States)

    Phosphorus losses through tile drained systems in agricultural landscapes may be causing the persistent eutrophication problems observed in surface water. The purpose of this paper is to evaluate the state of the science in the Agricultural Policy/Environmental eXtender (APEX) model related to surf...

  20. Framework for parameterizing and validating APEX to support NTT

    Science.gov (United States)

    The Agricultural Policy Environmental eXtender (APEX) is the process model underlying the Nutrient Tracking Tool (NTT). The NTT provides users, primarily farmers and crop consultants, with the opportunity to compare the effects of two scenarios, practice combinations, or other alternative conditions...

  1. The Doppler paradigm and the APEX-EPOS-ORANGE quandary

    International Nuclear Information System (INIS)

    Griffin, J.J.

    1995-01-01

    The experimental detection of the sharp lines of the (e + e - ) Puzzle is viewed as a struggle against Doppler broadening. Gedanken experiments which are realistic in zeroth order of detail are analyzed to show that the ORANGE and EPOS/I geometries select narrower slices of a Doppler broadened line than spherically inclusive (APEX and EPOS/II -like) apparati. Roughly speaking, the latter require event-by-event Doppler reconstruction simply to regain an even footing with the former. This suggests that APEX' or EPOS/II's coincident pair distributions must be statistically superior to those of EPOS/I or ORANGE in order to support a comparable inference about sharp structure. Under such circumstances, independent alternative data is invaluable. Therefore, a corroboration of Sakai's 330.1 keV ( + or e - bombardments of U and Th targets could prove crucial

  2. Apex Dips of Experimental Flux Ropes: Helix or Cusp?

    Energy Technology Data Exchange (ETDEWEB)

    Wongwaitayakornkul, Pakorn; Haw, Magnus A.; Bellan, Paul M. [Applied Physics, California Institute of Technology, Pasadena, CA 91125 (United States); Li, Hui [Theoretical Division, Los Alamos National Laboratory, Mail Stop B227, Los Alamos, NM 87545 (United States); Li, Shengtai, E-mail: pwongwai@caltech.edu, E-mail: mhaw@caltech.edu [Mathematical Modeling and Analysis, Los Alamos National Laboratory, Mail Stop B284, Los Alamos, NM 87545 (United States)

    2017-10-20

    We present a new theory for the presence of apex dips in certain experimental flux ropes. Previously such dips were thought to be projections of a helical loop axis generated by the kink instability. However, new evidence from experiments and simulations suggest that the feature is a 2D cusp rather than a 3D helix. The proposed mechanism for cusp formation is a density pileup region generated by nonlinear interaction of neutral gas cones emitted from fast-gas nozzles. The results indicate that density perturbations can result in large distortions of an erupting flux rope, even in the absence of significant pressure or gravitational forces. The density pileup at the apex also suppresses the m = 1 kink mode by acting as a stationary node. Consequently, more accurate density profiles should be considered when attempting to model the stability and shape of solar and astrophysical flux ropes.

  3. The electrical network of maize root apex is gravity dependent.

    Science.gov (United States)

    Masi, Elisa; Ciszak, Marzena; Comparini, Diego; Monetti, Emanuela; Pandolfi, Camilla; Azzarello, Elisa; Mugnai, Sergio; Baluška, Frantisek; Mancuso, Stefano

    2015-01-15

    Investigations carried out on maize roots under microgravity and hypergravity revealed that gravity conditions have strong effects on the network of plant electrical activity. Both the duration of action potentials (APs) and their propagation velocities were significantly affected by gravity. Similarly to what was reported for animals, increased gravity forces speed-up APs and enhance synchronized electrical events also in plants. The root apex transition zone emerges as the most active, as well as the most sensitive, root region in this respect.

  4. Oysters as biomonitors of the apex barge oil spill

    International Nuclear Information System (INIS)

    Wade, T.L.; Jackson, T.J.; McDonald, T.J.; Wilkinson, D.L.; Brooks, J.M.

    1993-01-01

    The collision of the Greek tanker ship Shinoussa resulted in a spill of an estimated 692,000 gallons of catalytic feed stock oil into Galveston Bay on July 28, 1990. Oysters were collected from Galveston Bay Todds Dump (GBTD) 235 days previous to the spill and 6, 37, 132, and 495 days after the spill. Oysters were also collected from Galveston Bay Redfish Island (GBRI), a site known to be impacted by the spill, 37 and 110 days after the spill. The concentration of the 24 polynuclear aromatic hydrocarbons (PAH) measured for the National Oceanic and Atmospheric Administration's national status and trends program (NS ampersand T) site showed a sharp increase from about 100 ng/g to over 600 ng/g one week after the spill compared to concentrations 235 days previous to the spill. The concentration of the 24 NS ampersand T PAH in oysters from GBRI ranges from 400 to over 1000 ng/g. Soon after the spill the concentration of the 24 NS ampersand T PAH at Todds Dump decreased to levels not statistically different from prespill samples. However, analyses of alkylated and sulfur containing aromatic compounds indicate the oysters were still contaminated with Apex barge oil at least 37 and 110 days after the spill at GBTD and GBRI, respectively. Data from NS ampersand T sampling at GBTD more than a year after the spill (495 days) indicates the presence of alkylated aromatic hydrocarbons that may be from Apex barge oil still in the area. It appears that a sink of Apex barge oil (i.e., in sediments) may periodically be released by storms or other events into the ecosystem near GBTD. Therefore, bioavailable Apex barge oil is still present and may adversely affect oysters 495 days after the spill

  5. Analysis of Apex Seal Friction Power Loss in Rotary Engines

    Science.gov (United States)

    Handschuh, Robert F.; Owen, A. Karl

    2010-01-01

    An analysis of the frictional losses from the apex seals in a rotary engine was developed. The modeling was initiated with a kinematic analysis of the rotary engine. Next a modern internal combustion engine analysis code was altered for use in a rotary engine to allow the calculation of the internal combustion pressure as a function of rotor rotation. Finally the forces from the spring, inertial, and combustion pressure on the seal were combined to provide the frictional horsepower assessment.

  6. SEPIA - a new single pixel receiver at the APEX telescope

    Science.gov (United States)

    Belitsky, V.; Lapkin, I.; Fredrixon, M.; Meledin, D.; Sundin, E.; Billade, B.; Ferm, S.-E.; Pavolotsky, A.; Rashid, H.; Strandberg, M.; Desmaris, V.; Ermakov, A.; Krause, S.; Olberg, M.; Aghdam, P.; Shafiee, S.; Bergman, P.; Beck, E. De; Olofsson, H.; Conway, J.; Breuck, C. De; Immer, K.; Yagoubov, P.; Montenegro-Montes, F. M.; Torstensson, K.; Pérez-Beaupuits, J.-P.; Klein, T.; Boland, W.; Baryshev, A. M.; Hesper, R.; Barkhof, J.; Adema, J.; Bekema, M. E.; Koops, A.

    2018-04-01

    Context. We describe the new Swedish-ESO PI Instrument for APEX (SEPIA) receiver, which was designed and built by the Group for Advanced Receiver Development (GARD), at Onsala Space Observatory (OSO) in collaboration with ESO. It was installed and commissioned at the APEX telescope during 2015 with an ALMA Band 5 receiver channel and updated with a new frequency channel (ALMA Band 9) in February 2016. Aim. This manuscript aims to provide, for observers who use the SEPIA receiver, a reference in terms of the hardware description, optics and performance as well as the commissioning results. Methods: Out of three available receiver cartridge positions in SEPIA, the two current frequency channels, corresponding to ALMA Band 5, the RF band 158-211 GHz, and Band 9, the RF band 600-722 GHz, provide state-of-the-art dual polarization receivers. The Band 5 frequency channel uses 2SB SIS mixers with an average SSB noise temperature around 45 K with IF (intermediate frequency) band 4-8 GHz for each sideband providing total 4 × 4 GHz IF band. The Band 9 frequency channel uses DSB SIS mixers with a noise temperature of 75-125 K with IF band 4-12 GHz for each polarization. Results: Both current SEPIA receiver channels are available to all APEX observers.

  7. Possible use of calcifying nanoparticles in immature root apex treatment

    Directory of Open Access Journals (Sweden)

    Mohammed S Alenazy

    2014-01-01

    Full Text Available Introduction: There are reports in the literature, which describe different techniques and materials in the challenging management of thin dentin walls and immature root apex. It has been suggested that calcifying nanoparticles (CNPs could be used in the management of these conditions. The Hypothesis: Compositionally modified CNPs made into a paste could become efficacious in managing thin dentin walls and immature root apex. Calcium and phosphate ions when mixed with CNPs could form a synthetic nanopaste that clinicians could use to manage thin dentin walls and to get a biological seal for immature root apex. Evaluation of the Hypothesis: CNPs can replicate and could facilitate the aggregations of calcium hydroxyapatite to produce a self-surrounding shell. These characteristics of CNPs could be used through their biomineralization process as initial nidus of calcification for further calcification progression to achieve total biological apical seal. If the hypothesis could be supported by biomineralization behavior of the paste (CNPs, Ca2 + , and PO4− , a new therapeutic agent would have been added to the armamentarium of endodontists. There is need for more in vivo and in vitro investigations of modified nanopaste to manage these conditions.

  8. APEX and ALPS, high power density technology programs in the U.S

    International Nuclear Information System (INIS)

    Wong, C.P.C.; Berk, S.; Abdou, M.; Mattas, R.

    1999-02-01

    In fiscal year (FY) 1998 two new fusion technology programs were initiated in the US, with the goal of making marked progress in the scientific understanding of technologies and materials required to withstand high plasma heat flux and neutron wall loads. APEX is exploring new and revolutionary concepts that can provide the capability to extract heat efficiently from a system with high neutron and surface heat loads while satisfying all the fusion power technology requirements and achieving maximum reliability, maintainability, safety, and environmental acceptability. ALPS program is evaluating advanced concepts including liquid surface limiters and divertors on the basis of such factors as their compatibility with fusion plasma, high power density handling capabilities, engineering feasibility, lifetime, safety and R and D requirements. The APEX and ALPS are three-year programs to specify requirements and evaluate criteria for revolutionary approaches in first wall, blanket and high heat flux component applications. Conceptual design and analysis of candidate concepts are being performed with the goal of selecting the most promising first wall, blanket and high heat flux component designs that will provide the technical basis for the initiation of a significant R and D effort beginning in FY2001. These programs are also considering opportunities for international collaborations

  9. Anode plasma dynamics in an extraction applied-B ion diode: effects on divergence, ion species and parasitic load

    International Nuclear Information System (INIS)

    Greenly, J.B.; Appartaim, R.K.; Olson, J.C.

    1996-01-01

    Analysis of data from the LION (1.2 MV, 300 kA, 40 ns) extraction applied-B diode allows a number of inferences regarding the effect of anode plasma dynamics on ion beam divergence, ion species composition, and diode impedance and power coupling. The two dominant features of anode plasma dynamics observed on LION are (1) plasma expansion away from the solid anode surface and into the accelerating gap during the beam pulse, and (2) evolution of the composition of the plasma during the pulse. The data presented in this paper characterize the plasma expansion, and suggest a possible picture of the mechanism of the plasma dynamics that could produce these basic features. (J.U.). 2 figs., 5 refs

  10. Anode plasma dynamics in an extraction applied-B ion diode: effects on divergence, ion species and parasitic load

    Energy Technology Data Exchange (ETDEWEB)

    Greenly, J B; Appartaim, R K; Olson, J C [Cornell Univ., Ithaca, NY (United States). Lab. of Plasma Studies

    1997-12-31

    Analysis of data from the LION (1.2 MV, 300 kA, 40 ns) extraction applied-B diode allows a number of inferences regarding the effect of anode plasma dynamics on ion beam divergence, ion species composition, and diode impedance and power coupling. The two dominant features of anode plasma dynamics observed on LION are (1) plasma expansion away from the solid anode surface and into the accelerating gap during the beam pulse, and (2) evolution of the composition of the plasma during the pulse. The data presented in this paper characterize the plasma expansion, and suggest a possible picture of the mechanism of the plasma dynamics that could produce these basic features. (J.U.). 2 figs., 5 refs.

  11. Magnetic-Laval-Nozzle Effect on a Magneto-Plasma-Dynamic Arcjet

    International Nuclear Information System (INIS)

    Inutake, Masaaki; Miyazaki, Hiroyuki; Yoshino, Kyohei; Tobari, Hiroyuki; Hattori, Kunihiko; Ando, Akira

    2003-01-01

    A magneto-plasma-dynamic arcjet (MPDA) is one of the promising candidates for a manned interplanetary space thruster with a higher specific impulse and larger thrust. An MPDA with an externally-applied magnetic nozzle is investigated to improve the thrust efficiency. From spectroscopic measurements of the MPDA plasma, it is found that with the increase in the discharge current not only the flow velocity but also the ion temperature increase near the muzzle of the MPDA with a uniform axial magnetic field and so the ion acoustic Mach number is limited to a value less than unity. By installing a Laval-type magnetic nozzle near the muzzle of the MPDA, the subsonic flow is successfully accelerated to a supersonic one by converting the ion thermal energy to the flow energy. The results are compared with the prediction by a1-D isentropic flow model

  12. Investigation of plasma dynamics during the growth of amorphous titanium dioxide thin films

    Science.gov (United States)

    Kim, Jin-Soo; Jee, Hyeok; Yu, Young-Hun; Seo, Hye-Won

    2018-06-01

    We have grown amorphous titanium dioxide thin films by reactive DC sputtering method using a different argon/oxygen partial pressure at a room temperature. The plasma dynamics of the process, reactive and sputtered gas particles was investigated via optical emission spectroscopy. We then studied the correlations between the plasma states and the structural/optical properties of the films. The growth rate and morphology of the titanium dioxide thin films turned out to be contingent with the population and the energy profile of Ar, O, and TiO plasma. In particular, the films grown under energetic TiO plasma have shown a direct band-to-band transition with an optical energy band gap up to ∼4.2 eV.

  13. Orbital Apex Syndrome Resulting from Mixed Bacterial Sphenoid Sinusitis

    Directory of Open Access Journals (Sweden)

    Mengfei Xiong

    2018-05-01

    Full Text Available Orbital apex syndrome (OAS is an uncommon disorder characterized by visual loss, ophthalmoplegia, ptosis and hypoaesthesia of the forehead[1]. OAS may result from a variety of inflammatory, infectious, neoplastic and vascular conditions that cause damage to the superior orbital fissure (with resultant oculomotor (III, trochlear (IV, abducens (VI and ophthalmic branch of the trigeminal nerve (V1 palsies and to the optic canal leading to optic nerve (II dysfunction. This case report describes the clinical development of OAS in a patient with bacterial sphenoid sinusitis.

  14. Using Apex To Construct CPM-GOMS Models

    Science.gov (United States)

    John, Bonnie; Vera, Alonso; Matessa, Michael; Freed, Michael; Remington, Roger

    2006-01-01

    process for automatically generating computational models of human/computer interactions as well as graphical and textual representations of the models has been built on the conceptual foundation of a method known in the art as CPM-GOMS. This method is so named because it combines (1) the task decomposition of analysis according to an underlying method known in the art as the goals, operators, methods, and selection (GOMS) method with (2) a model of human resource usage at the level of cognitive, perceptual, and motor (CPM) operations. CPM-GOMS models have made accurate predictions about behaviors of skilled computer users in routine tasks, but heretofore, such models have been generated in a tedious, error-prone manual process. In the present process, CPM-GOMS models are generated automatically from a hierarchical task decomposition expressed by use of a computer program, known as Apex, designed previously to be used to model human behavior in complex, dynamic tasks. An inherent capability of Apex for scheduling of resources automates the difficult task of interleaving the cognitive, perceptual, and motor resources that underlie common task operators (e.g., move and click mouse). The user interface of Apex automatically generates Program Evaluation Review Technique (PERT) charts, which enable modelers to visualize the complex parallel behavior represented by a model. Because interleaving and the generation of displays to aid visualization are automated, it is now feasible to construct arbitrarily long sequences of behaviors. The process was tested by using Apex to create a CPM-GOMS model of a relatively simple human/computer-interaction task and comparing the time predictions of the model and measurements of the times taken by human users in performing the various steps of the task. The task was to withdraw $80 in cash from an automated teller machine (ATM). For the test, a Visual Basic mockup of an ATM was created, with a provision for input from (and measurement

  15. APEX accelerator cycle for transmutation of long-lived fission wastes

    International Nuclear Information System (INIS)

    Powell, J.; Steinberg, M.; Takahashi, H.; Grand, P.; Botts, T.; Kouts, H.J.C.

    1980-01-01

    Based on preliminary studies, some conclusions can be drawn concerning the Accelerator Fuel Enricher and Fission Product Exterminator (APEX). APEX-1 and APEX-2 systems can destroy TU's, 137 Cs, and 90 Sr at acceptable cost and efficiency. The principal difference between APEX-1 and APEX-2 is the in-reactor and in-circuit inventory of 137 Cs and 90 Sr. Stable and low hazard wastes can be disposed of by burial. Accelerator breeders can effectively sustain a fission reactor economy indefinitely. Military waste can be blended into commercial fuel cycle for transmutation. Accelerator and target technologies appear practical and could be developed in a few years. More detailed studies are needed to better define the technical and economic features of the LAFER and APEX cycles, so that comparative assessments can be made between these cycles, as well as with other transmutation and waste disposal concepts

  16. Analysis of petrous apex meningocele associated with meningioma. Is there any relation with chronic intracranial hypertension?

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Wan-Qun; Huang, Biao; Liang, Chang-Hong [Southern Medical University, The Second School of Clinical Medicine, Guangzhou (China); Guangdong Academy of Medical Sciences, Department of Radiology, Guangdong General Hospital, Guangzhou, Guangdong (China); Feng, Jie-Ying [Nanhai Hospital Affiliated Southern Medical University, Department of Radiology, Foshan, Guangdong (China); Liu, Hong-Jun [Guangdong Academy of Medical Sciences, Department of Radiology, Guangdong General Hospital, Guangzhou, Guangdong (China)

    2018-02-15

    Petrous apex meningocele (PAM) is an uncommon cystic lesion involving the petrous apex. The underlying cause of PAM may be related to chronic elevated intracranial pressure. The aim of the study was to explore the relationship between PAM and meningioma and between PAM and other intracranial hypertension findings. Two hundred seventy-eight consecutive patients with meningiomas were retrospectively studied. Fifty age- and gender-matched controls were also enrolled in this study. The incidence of PAM, empty sella, tortuosity of the optic nerve, and hydrops of optic nerve sheath was evaluated. The maximum width, area, volume of each PAM, or Meckel's cave and volume of meningioma were measured in controls and patients, separately. One hundred fifty-nine (57.19%) patients were detected with coexistent PAMs. One hundred twenty-five patients had bilateral PAMs, 34 had unilateral lesions, and the remaining 119 did not have PAM. Two subjects (4/50) had unilateral PAMs in normal controls. The maximum width, area, volume of PAM, or Meckel's cave were significantly larger in the patients with bilateral PAM group than those in the unilateral PAM group, in the group without PAM, and those in control group (p = 0.000). The volume of meningioma was positively correlated with the PAM volume (r = 0.48). There was a positive correlation for the incidence between PAM and (1) empty sella (r = 0.901) and (2) tortuosity of the optic nerves and hydrops of the optic sheath (r = 0.825). Coexistence of PAMs with meningiomas is not rare in incidence, and it suggests a potential role for chronically elevated intracranial pressure and disturbance of CSF circulation in their pathophysiology. (orig.)

  17. Analysis of petrous apex meningocele associated with meningioma. Is there any relation with chronic intracranial hypertension?

    International Nuclear Information System (INIS)

    Yang, Wan-Qun; Huang, Biao; Liang, Chang-Hong; Feng, Jie-Ying; Liu, Hong-Jun

    2018-01-01

    Petrous apex meningocele (PAM) is an uncommon cystic lesion involving the petrous apex. The underlying cause of PAM may be related to chronic elevated intracranial pressure. The aim of the study was to explore the relationship between PAM and meningioma and between PAM and other intracranial hypertension findings. Two hundred seventy-eight consecutive patients with meningiomas were retrospectively studied. Fifty age- and gender-matched controls were also enrolled in this study. The incidence of PAM, empty sella, tortuosity of the optic nerve, and hydrops of optic nerve sheath was evaluated. The maximum width, area, volume of each PAM, or Meckel's cave and volume of meningioma were measured in controls and patients, separately. One hundred fifty-nine (57.19%) patients were detected with coexistent PAMs. One hundred twenty-five patients had bilateral PAMs, 34 had unilateral lesions, and the remaining 119 did not have PAM. Two subjects (4/50) had unilateral PAMs in normal controls. The maximum width, area, volume of PAM, or Meckel's cave were significantly larger in the patients with bilateral PAM group than those in the unilateral PAM group, in the group without PAM, and those in control group (p = 0.000). The volume of meningioma was positively correlated with the PAM volume (r = 0.48). There was a positive correlation for the incidence between PAM and (1) empty sella (r = 0.901) and (2) tortuosity of the optic nerves and hydrops of the optic sheath (r = 0.825). Coexistence of PAMs with meningiomas is not rare in incidence, and it suggests a potential role for chronically elevated intracranial pressure and disturbance of CSF circulation in their pathophysiology. (orig.)

  18. Modeling Halophytic Plants in APEX for Sustainable Water and Agriculture

    Science.gov (United States)

    DeRuyter, T.; Saito, L.; Nowak, B.; Rossi, C.; Toderich, K.

    2013-12-01

    A major problem for irrigated agricultural production is soil salinization, which can occur naturally or can be human-induced. Human-induced, or secondary salinization, is particularly a problem in arid and semi-arid regions, especially in irrigated areas. Irrigated land has more than twice the production of rainfed land, and accounts for about one third of the world's food, but nearly 20% of irrigated lands are salt-affected. Many farmers worldwide currently seasonally leach their land to reduce the soil salt content. These practices, however, create further problems such as a raised groundwater table, and salt, fertilizer, and pesticide pollution of nearby lakes and groundwater. In Uzbekistan, a combination of these management practices and a propensity to cultivate 'thirsty' crops such as cotton has also contributed to the Aral Sea shrinking nearly 90% by volume since the 1950s. Most common agricultural crops are glycophytes that have reduced yields when subjected to salt-stress. Some plants, however, are known as halophytic or 'salt-loving' plants and are capable of completing their life-cycle in higher saline soil or water environments. Halophytes may be useful for human consumption, livestock fodder, or biofuel, and may also be able to reduce or maintain salt levels in soil and water. To assess the potential for these halophytes to assist with salinity management, we are developing a model that is capable of tracking salinity under different management practices in agricultural environments. This model is interdisciplinary as it combines fields such as plant ecology, hydrology, and soil science. The US Department of Agriculture (USDA) model, Agricultural Policy/Environmental Extender (APEX), is being augmented with a salinity module that tracks salinity as separate ions across the soil-plant-water interface. The halophytes Atriplex nitens, Climacoptera lanata, and Salicornia europaea are being parameterized and added into the APEX model database. Field sites

  19. Gain and frequency tuning within the mouse cochlear apex

    Energy Technology Data Exchange (ETDEWEB)

    Oghalai, John S.; Raphael, Patrick D. [Department of Otolaryngology, Stanford University School of Medicine, Stanford, California (United States); Gao, Simon [Department of Otolaryngology, Stanford University School of Medicine, Stanford, California (United States); Department of Bioengineering, Rice University, Houston, Texas (United States); Lee, Hee Yoon [Department of Otolaryngology, Stanford University School of Medicine, Stanford, California (United States); Department of Electrical Engineering, Stanford University, Stanford, California (United States); Groves, Andrew K. [Department of Neuroscience, Department of Molecular and Human Genetics, and Program in Developmental Biology, Baylor College of Medicine, Houston, Texas (United States); Zuo, Jian [Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, Tennessee (United States); Applegate, Brian E. [Department of Biomedical Engineering, Texas A& M University, College Station, Texas (United States)

    2015-12-31

    Normal mammalian hearing requires cochlear outer hair cell active processes that amplify the traveling wave with high gain and sharp tuning, termed cochlear amplification. We have used optical coherence tomography to study cochlear amplification within the apical turn of the mouse cochlea. We measured not only classical basilar membrane vibratory tuning curves but also vibratory responses from the rest of the tissues that compose the organ of Corti. Basilar membrane tuning was sharp in live mice and broad in dead mice, whereas other regions of the organ of Corti demonstrated phase shifts consistent with additional filtering beyond that provided by basilar membrane mechanics. We use these experimental data to support a conceptual framework of how cochlear amplification is tuned within the mouse cochlear apex. We will also study transgenic mice with targeted mutations that affect different biomechanical aspects of the organ of Corti in an effort to localize the underlying processes that produce this additional filtering.

  20. Gain and frequency tuning within the mouse cochlear apex

    International Nuclear Information System (INIS)

    Oghalai, John S.; Raphael, Patrick D.; Gao, Simon; Lee, Hee Yoon; Groves, Andrew K.; Zuo, Jian; Applegate, Brian E.

    2015-01-01

    Normal mammalian hearing requires cochlear outer hair cell active processes that amplify the traveling wave with high gain and sharp tuning, termed cochlear amplification. We have used optical coherence tomography to study cochlear amplification within the apical turn of the mouse cochlea. We measured not only classical basilar membrane vibratory tuning curves but also vibratory responses from the rest of the tissues that compose the organ of Corti. Basilar membrane tuning was sharp in live mice and broad in dead mice, whereas other regions of the organ of Corti demonstrated phase shifts consistent with additional filtering beyond that provided by basilar membrane mechanics. We use these experimental data to support a conceptual framework of how cochlear amplification is tuned within the mouse cochlear apex. We will also study transgenic mice with targeted mutations that affect different biomechanical aspects of the organ of Corti in an effort to localize the underlying processes that produce this additional filtering

  1. Hidden dental diversity in the oldest terrestrial apex predator Dimetrodon.

    Science.gov (United States)

    Brink, Kirstin S; Reisz, Robert R

    2014-01-01

    Paleozoic sphenacodontid synapsids are the oldest known fully terrestrial apex predators. Dimetrodon and other sphenacodontids are the first terrestrial vertebrates to have strong heterodonty, massive skulls and well-developed labio-lingually compressed and recurved teeth with mesial and distal cutting edges (carinae). Here we reveal that the dentition of Dimetrodon and other sphenacodontids is diverse. Tooth morphology includes simple carinae with smooth cutting edges and elaborate enamel features, including the first occurrence of cusps and true denticles (ziphodonty) in the fossil record. A time-calibrated phylogenetic analysis indicates that changes in dental morphology occur in the absence of any significant changes in skull morphology, suggesting that the morphological change is associated with changes in feeding style and trophic interactions in these ecosystems. In addition, the available evidence indicates that ziphodonty evolved for the first time in the largest known species of the genus Dimetrodon and independently from the ziphodont teeth observed in some therapsids.

  2. A simulated plasma disruption experiment using a magneto-plasma-dynamic arcjet

    International Nuclear Information System (INIS)

    Madarame, H.; Sukegawa, T.; Okamoto, K.

    1991-01-01

    If a melt layer is expelled by a strong electromagnetic force from some places during a plasma disruption, the wall thickness is reduced there remarkably. Although this phenomenon is considered as a very important issue, it has not been studied so far because of its difficulty and complexity. In this study, the phenomenon was simulated using a magneto-plasma-dynamic (MPD) arcjet. The MPD arcjet was used as both a heat source and an electric current source. The current flowed radially in a stainless steel test piece installed in a transverse magnetic field. The circumferential electromagnetic force generated a swirl flow in the melt layer, causing a centrifugal force, which thinned the central part of the round region and formed a circular embankment on the fringe. A numerical code was developed which could calculate the melting, the evaporation and the melt layer movement by the centrifugal force and the beam pressure. The calculational results on the melting depth and the thickness reduction in the central part were compared with experiment. (orig.)

  3. Explosive-Emission Plasma Dynamics in Ion Diode in Double-Pulse Mode

    International Nuclear Information System (INIS)

    Pushkarev, Alexander I.; Isakova, Yulia I.

    2011-01-01

    The results of an experimental investigation of explosive-emission plasma dynamics in an ion diode with self-magnetic insulation are presented. The investigations were accomplished at the TEMP-4M accelerator set in a mode of double pulse formation. Plasma behaviour in the anode-cathode gap was analyzed according to both the current-voltage characteristics of the diode (time resolution of 0.5 ns) and thermal imprints on a target (spatial resolution of 0.8 mm). It was shown that when plasma formation at the potential electrode was complete, and up until the second (positive) pulse, the explosive-emission plasma expanded across the anode-cathode gap with a speed of 1.3±0.2 cm/μs. After the voltage polarity at the potential electrode was reversed (second pulse), the plasma erosion in the anode-cathode gap (similar to the effect of a plasma opening switch) occurred. During the generation of an ion beam the size of the anode-cathode gap spacing was determined by the thickness of the plasma layer on the potential electrode and the layer thickness of the electrons drifting along the grounded electrode. (15th asian conference on electrical discharge)

  4. Growth plate closure: Apex view on bone scan

    International Nuclear Information System (INIS)

    Giles, P.H.; Trochei, M.; Yeates, K.

    1984-01-01

    Angular deformities of the extremities in children following premature closure of the growth plate are well known. The deformities depend on the position of an osseus bridge which forms between the epiphysis and metaphysis. Several surgical procedures including resection of the osseus bridge have been described, however, delineation of the site of fusion is difficult to define. The commonest site of growth plate arrest is the distal femoral or proximal tibial growth plate. A new technique using the bone scan has been developed which accurately defines the area and position of these osseus bridges. Two hours after injection of technetium 99m methylene diphosphonate apex views of the affected distal femoral growth plate were performed. The knee was flexed into its smallest angle. Using a pinhole collimator the gamma camera was angled to face the affected growth plate end on. The image was collected onto computer and analysed by: (I) regions of interest over segments of the growth plate to calculate the relative area of total growth plate affected: (II) generating histograms: (III) thresholding or performing isocontours to accentuate abnormal areas. The growth plate is normally uniformly increased when compared to the normal shaft of the bone. Fusion across the plate appears as an area of diminished uptake. The apex view gives a unique functional map of the growth plate such that abnormal areas are displayed, and the site, size and position of osseus fusion obtained. The technique has the potential for determining the metabolic activity of the growth plate before and after surgery. Serial studies will allow assessment of regneration of the plate and reformation of new osseus bridges

  5. Multisite Evaluation of APEX for Water Quality: II. Regional Parameterization.

    Science.gov (United States)

    Nelson, Nathan O; Baffaut, Claire; Lory, John A; Anomaa Senaviratne, G M M M; Bhandari, Ammar B; Udawatta, Ranjith P; Sweeney, Daniel W; Helmers, Matt J; Van Liew, Mike W; Mallarino, Antonio P; Wortmann, Charles S

    2017-11-01

    Phosphorus (P) Index assessment requires independent estimates of long-term average annual P loss from fields, representing multiple climatic scenarios, management practices, and landscape positions. Because currently available measured data are insufficient to evaluate P Index performance, calibrated and validated process-based models have been proposed as tools to generate the required data. The objectives of this research were to develop a regional parameterization for the Agricultural Policy Environmental eXtender (APEX) model to estimate edge-of-field runoff, sediment, and P losses in restricted-layer soils of Missouri and Kansas and to assess the performance of this parameterization using monitoring data from multiple sites in this region. Five site-specific calibrated models (SSCM) from within the region were used to develop a regionally calibrated model (RCM), which was further calibrated and validated with measured data. Performance of the RCM was similar to that of the SSCMs for runoff simulation and had Nash-Sutcliffe efficiency (NSE) > 0.72 and absolute percent bias (|PBIAS|) 90%) and was particularly ineffective at simulating sediment loss from locations with small sediment loads. The RCM had acceptable performance for simulation of total P loss (NSE > 0.74, |PBIAS| < 30%) but underperformed the SSCMs. Total P-loss estimates should be used with caution due to poor simulation of sediment loss. Although we did not attain our goal of a robust regional parameterization of APEX for estimating sediment and total P losses, runoff estimates with the RCM were acceptable for P Index evaluation. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  6. Localization of the prostatic apex using CT for radiation treatment planning

    International Nuclear Information System (INIS)

    Li Xiaomei; Gao Xianshu; Guo Xuemei; Li Yagang; Wang Xiaoying

    2011-01-01

    Objective: In this retrospective study, we analyzed the magnetic resonance imaging (MRI) and computed tomography (CT) scans of patients with prostate cancer to investigate the relationship between the apex of prostate and the anatomic structures visible in CT, and to provide evidence for localizing the prostatic apex in radiation treatment planning. Methods: MRI and CT scans from 108 patients with prostate cancer were analyzed to measure the distance between the prostatic apex and the bottom of ischial tuberosities, the bottom of obturator foramen, the bottom of pubic symphysis and the bulb of the penis. The volume of prostate was calculated and the relationship between the size of the prostate and the localization of the prostatic apex was analyzed. Results: The prostatic apex is located 13.1 mm ± 3.3 mm superior to the bulb of the penis, 11.0 mm ± 5.4 mm superior to the bottom of obturator foramen, 31.3 mm ± 5.5 mm superior to the bottom of ischial tuberosities, and 7.1 mm ± 4.7 mm superior to the bottom of obturator foramen. There was no correlation between the size of prostate and the localization of the prostatic apex (R =0.07, -0.33, all P > 0.05). Conclusions: Ninety-five percent of patients had a prostatic apex that is above the bulb of the penis 6 mm, and 100% of patients had a prostatic apex that is above the bottom of obturator foramen. (authors)

  7. APEX simulation: environmental benefits of agroforestry and grass buffers on corn-soybean watersheds

    Science.gov (United States)

    The Agricultural Policy Environmental Extender (APEX) model has the ability to simulate the effects of vegetative filter strips on runoff and pollutant loadings from agricultural watersheds. The objectives of this study were to calibrate and validate the APEX model for three adjacent watersheds and...

  8. Coding Instructions, Worksheets, and Keypunch Sheets for M.E.T.R.O.-APEX Simulation.

    Science.gov (United States)

    Michigan Univ., Ann Arbor. Environmental Simulation Lab.

    Compiled in this resource are coding instructions, worksheets, and keypunch sheets for use in the M.E.T.R.O.-APEX simulation, described in detail in documents ED 064 530 through ED 064 550. Air Pollution Exercise (APEX) is a computerized college and professional level "real world" simulation of a community with urban and rural problems, industrial…

  9. Relation of Gothic arch apex to dentist-assisted centric relation.

    Science.gov (United States)

    Myers, M; Dziejma, R; Goldberg, J; Ross, R; Sharry, J

    1980-07-01

    These data suggest that the widely held belief that thumb pressure can position the mandible consistently more posterior than the position indicated by the Gothic arch apex is unfounded. Furthermore, this study provides no evidence to support the contention that the dentist-assisted jaw relation is more reproducible than the relation indicated by the Gothic arch apex.

  10. Modeling the fate and transport of bacteria in agricultural and pasture lands using APEX

    Science.gov (United States)

    The Agricultural Policy/Environmental eXtender (APEX) model is a whole farm to small watershed scale continuous simulation model developed for evaluating various land management strategies. The current version, APEX0806, does not have the modeling capacity for fecal indicator bacteria fate and trans...

  11. Bacteria transport simulation using APEX model in the Toenepi watershed, New Zealand

    Science.gov (United States)

    The Agricultural Policy/Environmental eXtender (APEX) model is a distributed, continuous, daily-time step small watershed-scale hydrologic and water quality model. In this study, the newly developed fecal-derived bacteria fate and transport subroutine was applied and evalated using APEX model. The e...

  12. CRED APEX Drifting Buoy Argos_ID 25321 Data in the Northwestern Hawaiian Islands, 200110-200404 (NODC Accession 0049436)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CRED APEX drifter Argos_ID 25321 was deployed in the region of NW Hawaiian Islands to assess ocean currents and sea surface temperature. APEX drifter data files...

  13. CRED APEX Drifting Buoy Argos_ID 24963 Data in the NW Hawaiian Islands, 200109-200506 (NODC Accession 0049436)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CRED APEX drifter Argos_ID 24963 was deployed in the region of NW Hawaiian Islands to assess ocean currents and sea surface temperature. APEX drifter data files...

  14. CRED APEX Drifting Buoy Argos_ID 26070 Data in the NW Hawaiian Islands, the Pacific Ocean

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CRED APEX drifter Argos_ID 26070 was deployed in the region of NW Hawaiian Islands to assess ocean currents and sea surface temperature. APEX drifter data files...

  15. Structure and stability of semiconductor tip apexes for atomic force microscopy

    International Nuclear Information System (INIS)

    Pou, P; Perez, R; Ghasemi, S A; Goedecker, S; Jelinek, P; Lenosky, T

    2009-01-01

    The short range force between the tip and the surface atoms, that is responsible for atomic-scale contrast in atomic force microscopy (AFM), is mainly controlled by the tip apex. Thus, the ability to image, manipulate and chemically identify single atoms in semiconductor surfaces is ultimately determined by the apex structure and its composition. Here we present a detailed and systematic study of the most common structures that can be expected at the apex of the Si tips used in experiments. We tackle the determination of the structure and stability of Si tips with three different approaches: (i) first principles simulations of small tip apexes; (ii) simulated annealing of a Si cluster; and (iii) a minima hopping study of large Si tips. We have probed the tip apexes by making atomic contacts between the tips and then compared force-distance curves with the experimental short range forces obtained with dynamic force spectroscopy. The main conclusion is that although there are multiple stable solutions for the atomically sharp tip apexes, they can be grouped into a few types with characteristic atomic structures and properties. We also show that the structure of the last atomic layers in a tip apex can be both crystalline and amorphous. We corroborate that the atomically sharp tips are thermodynamically stable and that the tip-surface interaction helps to produce the atomic protrusion needed to get atomic resolution.

  16. Massive consumption of gelatinous plankton by Mediterranean apex predators.

    Directory of Open Access Journals (Sweden)

    Luis Cardona

    Full Text Available Stable isotopes of carbon and nitrogen were used to test the hypothesis that stomach content analysis has systematically overlooked the consumption of gelatinous zooplankton by pelagic mesopredators and apex predators. The results strongly supported a major role of gelatinous plankton in the diet of bluefin tuna (Thunnus thynnus, little tunny (Euthynnus alletteratus, spearfish (Tetrapturus belone and swordfish (Xiphias gladius. Loggerhead sea turtles (Caretta caretta in the oceanic stage and ocean sunfish (Mola mola also primarily relied on gelatinous zooplankton. In contrast, stable isotope ratios ruled out any relevant consumption of gelatinous plankton by bluefish (Pomatomus saltatrix, blue shark (Prionace glauca, leerfish (Lichia amia, bonito (Sarda sarda, striped dolphin (Stenella caerueloalba and loggerhead sea turtles (Caretta caretta in the neritic stage, all of which primarily relied on fish and squid. Fin whales (Balaenoptera physalus were confirmed as crustacean consumers. The ratios of stable isotopes in albacore (Thunnus alalunga, amberjack (Seriola dumerili, blue butterfish (Stromaeus fiatola, bullet tuna (Auxis rochei, dolphinfish (Coryphaena hyppurus, horse mackerel (Trachurus trachurus, mackerel (Scomber scombrus and pompano (Trachinotus ovatus were consistent with mixed diets revealed by stomach content analysis, including nekton and crustaceans, but the consumption of gelatinous plankton could not be ruled out completely. In conclusion, the jellyvorous guild in the Mediterranean integrates two specialists (ocean sunfish and loggerhead sea turtles in the oceanic stage and several opportunists (bluefin tuna, little tunny, spearfish, swordfish and, perhaps, blue butterfish, most of them with shrinking populations due to overfishing.

  17. Acute orbital apex syndrome and rhino-orbito-cerebral mucormycosis

    Directory of Open Access Journals (Sweden)

    Anders UM

    2015-04-01

    Full Text Available Ursula M Anders,1 Elise J Taylor,1 Joseph R Martel,1–3 James B Martel1–3 1Research Center, Martel Eye Medical Group, Rancho Cordova, 2Graduate Medical Education, California Northstate University College of Medicine, Elk Grove, 3Department of Ophthalmology, Dignity Health, Carmichael, CA, USA Purpose: To demonstrate the successful clinical identification and management of rhino-orbital mucormycosis, a fungal infection with a high mortality rate. Patients and methods: A diabetic male patient with a headache and orbital apex syndrome in the right eye was examined using computed tomography (CT and magnetic resonance imaging (MRI for a possible fungal infection. Endoscopic surgical resection was performed and a pathology sample was taken. Specimens were prepared with Gömöri methenamine silver and hematoxylin and eosin staining. The patient was treated with liposomal amphotericin B 400 mg daily, followed by posaconazole 400 mg twice daily. Results: CT and MRI revealed a mass of the right sphenoid spreading into the orbit, indicative of a fungal infection. The biopsy confirmed the diagnosis of mucormycosis. Complete recovery of eyelid and oculomotor function was achieved after 10 months of treatment, although the patient continues to suffer from irreversible blindness in the right eye due to optic nerve atrophy. He has been without signs or symptoms of recurrence. Conclusion: Patients with rhino-orbito-cerebral mucormycosis need extensive surgical and medical treatment to maximize outcomes. Success requires multidisciplinary management. Keywords: ophthalmoplegia, sixth nerve palsy, diabetes mellitus, nephrotoxicity, amphotericin B, posaconazole

  18. Transcavernous Approach to the Basilar Apex: A Cadaveric Prosection

    Science.gov (United States)

    Sellin, Jonathan N; Navarro, Jovany C; Batjer, Hunt H; Van Loveren, Harry; Duckworth, Edward A

    2018-01-01

    The transcavernous approach to the basilar artery, as initially described by Dolenc, is one of the most common and elegant approaches to the region. It affords a generous working and viewing angle, but it can be technically challenging and requires attention to detail at each step. We investigate this approach in this report via a cadaveric prosection with a focus on the value of each of the component steps in improving surgical view and exposure. The transcavernous approach steps are divided into extradural stages: orbitozygomatic osteotomy (a modern adjunct to Dolenc’s original description), drilling of the lesser sphenoid wing, and anterior clinoidectomy; and intradural stages: wide splitting of the Sylvian fissure, unroofing of the oculomotor and trochlear nerves, and posterior clinoidectomy. The surgical windows afforded by each step in the approach are illustrated using microscopic images taken during the cadaveric prosection of a donor who happened to harbor a basilar apex aneurysm. An illustrative case and artist illustrations are used to emphasize the relative value of each step of the transcavernous exposure. PMID:29682431

  19. Assessment of tumors of the lung apex by imaging techniques

    International Nuclear Information System (INIS)

    Rueda, J.; Serrano, F.; Pain, M.I.; Rodriguez, F.

    1996-01-01

    The purpose of this study was to analyze the value of MR in the preoperative staging of tumors of the lung apex and detection of local invasion of adjacent structures to determine its influence on the therapeutic approach. We obtained plain X-ray images in two planes, as well as CT and Mr images, in 12 patients with Pan coast tumor in whom there was surgical (n=8) or clinical (n=4) evidence of invasion. The objective was to assess local infiltration of brain stem and chest wall soft tissue, enveloping of the subclavian artery, substantial involvement of the brachial plexus and destruction of the vertebral body. In our series, MR was superior to the other imaging techniques in predicting the involvement of the structures surrounding the tumor. In conclusion, MR should be performed in a patient diagnosed by plain radiography as having an apical tumors to assess local tumor extension, while CT should be done to detect mediastinal lymph node involvement and distant metastases. 19 refs

  20. Electronic apex locator: A comprehensive literature review — Part II: Effect of different clinical and technical conditions on electronic apex locator′s accuracy

    Directory of Open Access Journals (Sweden)

    Hamid Razavian

    2014-01-01

    Full Text Available Introduction: To investigate the effects of different clinical and technical conditions on the accuracy of electronic apex locators (EALs. Materials and Methods: "Tooth apex," "dental instrument," "odontometry," "electronic medical," and "electronic apex locator" were searched as primary identifiers via Medline/PubMed, Cochrane library, and Scopus data base up to 30 July 2013. Original articles that fulfilled the inclusion criteria were selected and reviewed. Results: Out of 402 relevant studies, 183 were selected based on the inclusion criteria. In this part, 75 studies are presented. Pulp vitality conditions and root resorption, types of files and irrigating materials do not affect an EAL′s accuracy; however, the file size and foramen diameter can affect its accuracy. Conclusions: Various clinical conditions such as the file size and foramen diameter may affect EALs′ accuracy. However, more randomized clinical trials are needed for definitive conclusion.

  1. Uranium analysis in urine by inductively coupled plasma dynamic reaction cell mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ejnik, John W. [Northern Michigan University, Chemistry Department, Marquette, MI (United States); Todorov, Todor I.; Mullick, Florabel G.; Centeno, Jose A. [Armed Forces Institute of Pathology (AFIP), Division of Biophysical Toxicology, Washington, DC (United States); Squibb, Katherine; McDiarmid, Melissa A. [University of Maryland, School of Medicine, Baltimore, MD (United States)

    2005-05-01

    Urine uranium concentrations are the best biological indicator for identifying exposure to depleted uranium (DU). Internal exposure to DU causes an increased amount of urine uranium and a decreased ratio of {sup 235}U/{sup 238}U in urine samples, resulting in measurements that vary between 0.00725 and 0.002 (i.e., natural and depleted uranium's {sup 235}U/{sup 238}U ratios, respectively). A method based on inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS) was utilized to identify DU in urine by measuring the quantity of total U and the {sup 235}U/{sup 238}U ratio. The quantitative analysis was achieved using {sup 233}U as an internal standard. The analysis was performed both with and without the reaction gas oxygen. The reaction gas converted ionized {sup 235}U{sup +} and {sup 238}U{sup +} into {sup 235}UO{sub 2}{sup +} (m/z=267) and {sup 238}UO{sub 2}{sup +} (m/z=270). This conversion was determined to be over 90% efficient. A polyatomic interference at m/z 234.8 was successfully removed from the {sup 235}U signal under either DRC operating conditions (with or without oxygen as a reaction gas). The method was validated with 15 urine samples of known uranium compositions. The method detection limit for quantification was determined to be 0.1 pg U mL{sup -1} urine and an average coefficient of variation (CV) of 1-2% within the sample measurements. The method detection limit for determining {sup 235}U/{sup 238}U ratio was 3.0 pg U mL{sup -1} urine. An additional 21 patient samples were analyzed with no information about medical history. The measured {sup 235}U/{sup 238}U ratio within the urine samples correctly identified the presence or absence of internal DU exposure in all 21 patients. (orig.)

  2. Apex predator and the cyclic competition in a rock-paper-scissors game of three species

    Science.gov (United States)

    Souza-Filho, C. A.; Bazeia, D.; Ramos, J. G. G. S.

    2017-06-01

    This work deals with the effects of an apex predator on the cyclic competition among three distinct species that follow the rules of the rock-paper-scissors game. The investigation develops standard stochastic simulations but is motivated by a procedure which is explained in the work. We add the apex predator as the fourth species in a system that contains three species that evolve following the standard rules of migration, reproduction, and predation, and study how the system evolves in this new environment, in comparison with the case in the absence of the apex predator. The results show that the apex predator engenders the tendency to spread uniformly in the lattice, contributing to destroy the spiral patterns, keeping biodiversity but diminishing the average size of the clusters of the species that compete cyclically.

  3. Crossing latitudes--long-distance tracking of an apex predator.

    Directory of Open Access Journals (Sweden)

    Luciana C Ferreira

    Full Text Available Tiger sharks (Galeocerdo cuvier are apex predators occurring in most tropical and warm temperate marine ecosystems, but we know relatively little of their patterns of residency and movement over large spatial and temporal scales. We deployed satellite tags on eleven tiger sharks off the north-western coast of Western Australia and used the Brownian Bridge kernel method to calculate home ranges and analyse movement behaviour. One individual recorded one of the largest geographical ranges of movement ever reported for the species, travelling over 4000 km during 517 days of monitoring. Tags on the remainder of the sharks reported for shorter periods (7-191 days. Most of these sharks had restricted movements and long-term (30-188 days residency in coastal waters in the vicinity of the area where they were tagged. Core home range areas of sharks varied greatly from 1166.9 to 634,944 km2. Tiger sharks spent most of their time in water temperatures between 23°-26°C but experienced temperatures ranging from 6°C to 33°C. One shark displayed seasonal movements among three distinct home range cores spread along most of the coast of Western Australia and generalized linear models showed that this individual had different patterns of temperature and depth occupancy in each region of the coast, with the highest probability of residency occurring in the shallowest areas of the coast with water temperatures above 23°C. These results suggest that tiger sharks can migrate over very large distances and across latitudes ranging from tropical to the cool temperate waters. Such extensive long-term movements may be a key element influencing the connectivity of populations within and among ocean basins.

  4. Characterization of somatic embryogenesis initiated from the Arabidopsis shoot apex.

    Science.gov (United States)

    Kadokura, Satoshi; Sugimoto, Kaoru; Tarr, Paul; Suzuki, Takamasa; Matsunaga, Sachihiro

    2018-04-28

    Somatic embryogenesis is one of the best examples of the remarkable developmental plasticity of plants, in which committed somatic cells can dedifferentiate and acquire the ability to form an embryo and regenerate an entire plant. In Arabidopsis thaliana, the shoot apices of young seedlings have been reported as an alternative tissue source for somatic embryos (SEs) besides the widely studied zygotic embryos taken from siliques. Although SE induction from shoots demonstrates the plasticity of plants more clearly than the embryo-to-embryo induction system, the underlying developmental and molecular mechanisms involved are unknown. Here we characterized SE formation from shoot apex explants by establishing a system for time-lapse observation of explants during SE induction. We also established a method to distinguish SE-forming and non-SE-forming explants prior to anatomical SE formation, enabling us to identify distinct transcriptome profiles of these two explants at SE initiation. We show that embryonic fate commitment takes place at day 3 of SE induction and the SE arises directly, not through callus formation, from the base of leaf primordia just beside the shoot apical meristem (SAM), where auxin accumulates and shoot-root polarity is formed. The expression domain of a couple of key developmental genes for the SAM transiently expands at this stage. Our data demonstrate that SE-forming and non-SE-forming explants share mostly the same transcripts except for a limited number of embryonic genes and root genes that might trigger the SE-initiation program. Thus, SE-forming explants possess a mixed identity (SAM, root and embryo) at the time of SE specification. Copyright © 2018. Published by Elsevier Inc.

  5. Frequency of the external resorptions of root apex

    Directory of Open Access Journals (Sweden)

    Opačić-Galić Vanja

    2004-01-01

    Full Text Available Root resorptions present a significant problem in endodontic therapy of the affected teeth and in dentistry in general. The objective of this study was to analyze, based on epidemiological and statistical research, the frequency of clinical incidence of pathological root resorptions in everyday practice related to localization, type of tooth, age and sex of patients. Radiographie documentation of patients treated from 1997 till 2002 at the Department of Conservative Dentistry and Endodontics, Faculty of Stomatology in Belgrade, was used as baseline for this study. Retroalveolar radiographs of teeth with visible signs of resorptions were singled out from 15654 patients' clinical records used for this study. The external resorptions were shown as radiolucent areas localized on various outer root surfaces, followed by significant or less significant resorption of lamina dura and alveolar bone. Out of all teeth analyzed in this study, 594 (3.79% showed some kind of resorption. The external resorptions were found to be more present in the upper jaw (55.10% and molars (50.30% than in the lower jaw (44.90% and single root teeth (49.70%, but in both cases without significant statistical differences. The most frequent localization of resorptions was root apex (82.44%. In regard to age, the most frequent resorptions were recorded in patients aged between 21 and 30 years (28.40%, and the lowest incidence was found in the youngest population (5.51%. The results also showed that resorptions were more frequent among the female population (59.04% than among the male population (40.96%. Based on these results, we may conclude that the external root resorptions are not a frequent clinical phenomenon. Proper and early diagnostics of such tissue pathology is one of the basic prerequisites for successful endodontic therapy of the affected root.

  6. Interference of apex locator, pulp tester and diathermy on pacemaker function

    OpenAIRE

    Narayanan Sriman; V Prabhakar; J S Bhuvaneswaran; N Subha

    2015-01-01

    Aim: The purpose of this study was to evaluate the effects of three electronic apex locators (EAL), electric pulp tester (EPT) and diathermy on pacemaker function in vitro. Materials and Methods: Three EALs: Root ZX (J. Morita Co., Tustin, CA, U.S.A.), Propex (Dentsply), Mini Apex locator (SybronEndo, Anaheim, CA, USA), EPT (Parkell pulp vitality tester Farmingdale, NY, USA) and Diathermy (Neomed 250 B) were tested for any interference with one pacemaker (A medtronic kappa KVDD901-serial ...

  7. Differential TOR activation and cell proliferation in Arabidopsis root and shoot apexes.

    Science.gov (United States)

    Li, Xiaojuan; Cai, Wenguo; Liu, Yanlin; Li, Hui; Fu, Liwen; Liu, Zengyu; Xu, Lin; Liu, Hongtao; Xu, Tongda; Xiong, Yan

    2017-03-07

    The developmental plasticity of plants relies on the remarkable ability of the meristems to integrate nutrient and energy availability with environmental signals. Meristems in root and shoot apexes share highly similar molecular players but are spatially separated by soil. Whether and how these two meristematic tissues have differential activation requirements for local nutrient, hormone, and environmental cues (e.g., light) remain enigmatic in photosynthetic plants. Here, we report that the activation of root and shoot apexes relies on distinct glucose and light signals. Glucose energy signaling is sufficient to activate target of rapamycin (TOR) kinase in root apexes. In contrast, both the glucose and light signals are required for TOR activation in shoot apexes. Strikingly, exogenously applied auxin is able to replace light to activate TOR in shoot apexes and promote true leaf development. A relatively low concentration of auxin in the shoot and high concentration of auxin in the root might be responsible for this distinctive light requirement in root and shoot apexes, because light is required to promote auxin biosynthesis in the shoot. Furthermore, we reveal that the small GTPase Rho-related protein 2 (ROP2) transduces light-auxin signal to activate TOR by direct interaction, which, in turn, promotes transcription factors E2Fa,b for activating cell cycle genes in shoot apexes. Consistently, constitutively activated ROP2 plants stimulate TOR in the shoot apex and cause true leaf development even without light. Together, our findings establish a pivotal hub role of TOR signaling in integrating different environmental signals to regulate distinct developmental transition and growth in the shoot and root.

  8. Lack of association between the APEX1 Asp148Glu polymorphism and sporadic amyotrophic lateral sclerosis.

    Science.gov (United States)

    Coppedè, Fabio; Lo Gerfo, Annalisa; Carlesi, Cecilia; Piazza, Selina; Mancuso, Michelangelo; Pasquali, Livia; Murri, Luigi; Migliore, Lucia; Siciliano, Gabriele

    2010-02-01

    Impairments in DNA repair enzymes have been observed in amyotrophic lateral sclerosis (ALS) tissues, particularly in the activity of the apurinic/apyrimidinic endonuclease 1 (APEX1). Moreover, it was suggested that the common APEX1 Asp148Glu polymorphism might be associated with ALS risk. To further address this question we performed the present study aimed at evaluating the contribution of the APEX1 Asp148Glu polymorphism in sporadic ALS (sALS) risk and clinical presentation, including age and site of onset and disease progression. We screened 134 sALS Italian patients and 129 matched controls for the presence of the APEX1 Asp148Glu polymorphism. No difference in APEX1 Asp148Glu allele and genotype frequencies was found between the groups, nor was the polymorphism associated with age and site of onset or disease progression. Present results do not support a role for the APEX1 Asp148Glu polymorphism in sALS pathogenesis in the Italian population.

  9. The APEX Quantitative Proteomics Tool: Generating protein quantitation estimates from LC-MS/MS proteomics results

    Directory of Open Access Journals (Sweden)

    Saeed Alexander I

    2008-12-01

    Full Text Available Abstract Background Mass spectrometry (MS based label-free protein quantitation has mainly focused on analysis of ion peak heights and peptide spectral counts. Most analyses of tandem mass spectrometry (MS/MS data begin with an enzymatic digestion of a complex protein mixture to generate smaller peptides that can be separated and identified by an MS/MS instrument. Peptide spectral counting techniques attempt to quantify protein abundance by counting the number of detected tryptic peptides and their corresponding MS spectra. However, spectral counting is confounded by the fact that peptide physicochemical properties severely affect MS detection resulting in each peptide having a different detection probability. Lu et al. (2007 described a modified spectral counting technique, Absolute Protein Expression (APEX, which improves on basic spectral counting methods by including a correction factor for each protein (called Oi value that accounts for variable peptide detection by MS techniques. The technique uses machine learning classification to derive peptide detection probabilities that are used to predict the number of tryptic peptides expected to be detected for one molecule of a particular protein (Oi. This predicted spectral count is compared to the protein's observed MS total spectral count during APEX computation of protein abundances. Results The APEX Quantitative Proteomics Tool, introduced here, is a free open source Java application that supports the APEX protein quantitation technique. The APEX tool uses data from standard tandem mass spectrometry proteomics experiments and provides computational support for APEX protein abundance quantitation through a set of graphical user interfaces that partition thparameter controls for the various processing tasks. The tool also provides a Z-score analysis for identification of significant differential protein expression, a utility to assess APEX classifier performance via cross validation, and a

  10. The applications of Complexity Theory and Tsallis Non-extensive Statistics at Solar Plasma Dynamics

    Science.gov (United States)

    Pavlos, George

    2015-04-01

    As the solar plasma lives far from equilibrium it is an excellent laboratory for testing complexity theory and non-equilibrium statistical mechanics. In this study, we present the highlights of complexity theory and Tsallis non extensive statistical mechanics as concerns their applications at solar plasma dynamics, especially at sunspot, solar flare and solar wind phenomena. Generally, when a physical system is driven far from equilibrium states some novel characteristics can be observed related to the nonlinear character of dynamics. Generally, the nonlinearity in space plasma dynamics can generate intermittent turbulence with the typical characteristics of the anomalous diffusion process and strange topologies of stochastic space plasma fields (velocity and magnetic fields) caused by the strange dynamics and strange kinetics (Zaslavsky, 2002). In addition, according to Zelenyi and Milovanov (2004) the complex character of the space plasma system includes the existence of non-equilibrium (quasi)-stationary states (NESS) having the topology of a percolating fractal set. The stabilization of a system near the NESS is perceived as a transition into a turbulent state determined by self-organization processes. The long-range correlation effects manifest themselves as a strange non-Gaussian behavior of kinetic processes near the NESS plasma state. The complex character of space plasma can also be described by the non-extensive statistical thermodynamics pioneered by Tsallis, which offers a consistent and effective theoretical framework, based on a generalization of Boltzmann - Gibbs (BG) entropy, to describe far from equilibrium nonlinear complex dynamics (Tsallis, 2009). In a series of recent papers, the hypothesis of Tsallis non-extensive statistics in magnetosphere, sunspot dynamics, solar flares, solar wind and space plasma in general, was tested and verified (Karakatsanis et al., 2013; Pavlos et al., 2014; 2015). Our study includes the analysis of solar plasma time

  11. The Role of APEX as a Pathfinder for AtLAST

    Science.gov (United States)

    Wyrowski, Friedrich

    2018-01-01

    Now more than 12 years in operation, the Atacama Pathfinder Experiment (APEX) 12 m submillimeter telescope has significantly contributed to a wide variety of submillimeter astronomy science areas, ranging from the discoveries of new molecules to large and deep imaging of the submillimeter sky. While ALMA operation is in full swing, APEX is strengthening its role not only as pathfinder for studying large source samples and spatial scales to prepare detailed high angular resolution ALMA follow ups, but also as fast response instruments to complement new results from ALMA. Furthermore, APEX ensures southern hemisphere access for submillimeter projects complementing archival Herschel research as well as new SOFIA science. With new broadband and multipixel receivers as well as large cameras for wide-field continuum imaging, APEX will pave the way towards the science envisioned with ATLAST. In this contribution, the current status and ongoing upgrades of APEX will be discussed, with an emphasis on the importance of continuous cutting edge science and state-of-the-art instrumentation that will bridge the gap towards ATLAST.

  12. Impact of conservation areas on trophic interactions between apex predators and herbivores on coral reefs.

    Science.gov (United States)

    Rizzari, Justin R; Bergseth, Brock J; Frisch, Ashley J

    2015-04-01

    Apex predators are declining at alarming rates due to exploitation by humans, but we have yet to fully discern the impacts of apex predator loss on ecosystem function. In a management context, it is critically important to clarify the role apex predators play in structuring populations of lower trophic levels. Thus, we examined the top-down influence of reef sharks (an apex predator on coral reefs) and mesopredators on large-bodied herbivores. We measured the abundance, size structure, and biomass of apex predators, mesopredators, and herbivores across fished, no-take, and no-entry management zones in the Great Barrier Reef Marine Park, Australia. Shark abundance and mesopredator size and biomass were higher in no-entry zones than in fished and no-take zones, which indicates the viability of strictly enforced human exclusion areas as tools for the conservation of predator communities. Changes in predator populations due to protection in no-entry zones did not have a discernible influence on the density, size, or biomass of different functional groups of herbivorous fishes. The lack of a relationship between predators and herbivores suggests that top-down forces may not play a strong role in regulating large-bodied herbivorous coral reef fish populations. Given this inconsistency with traditional ecological theories of trophic cascades, trophic structures on coral reefs may need to be reassessed to enable the establishment of appropriate and effective management regimes. © 2014 Society for Conservation Biology.

  13. Analysis of plasma dynamic response to modulated electron cyclotron heating in TCV tokamak

    International Nuclear Information System (INIS)

    Pavlov, I.

    2008-01-01

    perturbed electron temperature with MECH source term can not be used for transport analysis in the presence of MECH-sawtooth coupling. Self-consistent time dependant transport simulations including a sawtooth relaxation model is capable of properly reproducing the effect of MECH-sawtooth phase coupling and can be used for transport analysis. On the basis of these simulations, an hypothesis for MECH-sawtooth coupling based on periodic modifications of magnetic shear was proposed. Additional information provided by HOS analysis enabled a correct interpretation of the plasma dynamic response to modulated heating in the presence of MECH-sawtooth coupling. (author)

  14. Analysis and Interpretation of the Plasma Dynamic Response to Additional Heating Power using different Diagnostics

    International Nuclear Information System (INIS)

    Manini, A.

    2002-07-01

    development of this work, the Electron Cyclotron Emission system (ECE) of ASDEX Upgrade is crucial since it allows local measurements of the electron temperature with high temporal and spatial resolutions. The analysis and interpretation of perturbative MECH discharges for power deposition localisation using different diagnostics, such as ECE and SXR measurements, are presented. The most important problem is related to the phase locking between the MECH and the sawtooth activity of the plasma, which disturbs both ECE and SXR measurements. Several techniques have been adopted to circumvent this difficulty. In particular, the Singular Value Decomposition (SVD) and the Generalised Singular Value Decomposition (GSVD) have been tested in both TCV and ASDEX Upgrade discharges. However, both methods are incapable of treating the problem correctly, which leads to potential misinterpretation of the results. A new method based on system identification using the SVD (SI-SVD) is developed and applied. This method, within reasonable limits induced by the assumption of linearity, is capable of simultaneously separating the MECH from the sawtooth contributions to both ECE electron temperature measurements and SXR emission measurements. Such a method is in particular applied to a NBI heated ASDEX Upgrade discharge in which MECH is added in order to analyse electron heat transport in a mostly ion-heated plasma. Since the NBI heating is also partly modulated with short pulses, which coincide with the sawtooth crashes to improve their stability, both the MECH and the NBI deposition profiles are determined. Moreover, treating the signals with the SI-SVD procedure enables a study of the plasma dynamic response also at higher MECH harmonic numbers. The procedure is then used to analyse MECH discharges in TCV using different diagnostics. The profiles determined using the ECE and soft X-ray measurements are compared and interpreted, demonstrating in particular that line integrated soft X

  15. In-Flight Spectral Calibration of the APEX Imaging Spectrometer Using Fraunhofer Lines

    Science.gov (United States)

    Kuhlmann, Gerrit; Hueni, Andreas; Damm, Aalexander; Brunner, Dominik

    2015-11-01

    The Airborne Prism EXperiment (APEX) is an imaging spectrometer which allows to observe atmospheric trace gases such as nitrogen dioxide (NO2). Using a high resolution spectrum of solar Fraunhofer lines, APEX measurements collected during flight have been spectrally calibrated for centre wavelength positions (CW) and instrument slit function (ISF) and compared to the laboratory calibration. We find that CWs depend strongly on both across- and along-track position due to spectral smile and CWs dependency on ambient pressure. The width of the ISF is larger than estimated from the laboratory calibration but can be described by a linear scaling of the laboratory values. The ISF width depends on across- but not on along-track direction. The results demonstrate the importance of characterizing and monitoring the instrument performance during flight and will be used to improve the Empa APEX NO2 retrieval algorithm.

  16. ALLSMOG, the APEX Low-redshift Legacy Survey for MOlecular Gas

    Science.gov (United States)

    Bothwell, M.; Cicone, C.; Wagg, J.; De Breuck, C..

    2017-09-01

    We report the completion of the APEX Low-redshift Legacy Survey for MOlecular Gas (ALLSMOG), an ESO Large Programme, carried out with the Atacama Pathfinder EXperiment (APEX) between 2013 and 2016. With a total of 327 hours of APEX observing time, we observed the 12CO(2-1) line in 88 nearby low-mass star-forming galaxies. We briefly outline the ALLSMOG goals and design, and describe a few science highlights that have emerged from the survey so far. We outline future work that will ensure that the ALLSMOG dataset continues to provide scientific value in the coming years. ALLSMOG was designed to be a reference legacy survey and as such all reduced data products are publicly available through the ESO Science Archive Phase 3 interface.

  17. Magnetic reconnection through the current sheets as the universal process for plasma dynamics in nonuniform magnetic fields

    International Nuclear Information System (INIS)

    Frank, A.G.; Bogdanov, S.Yu.; Burilina, V.B.; Kyrie, N.P.

    1997-01-01

    Laboratory experiments are reported, in which we studied the possibilities of the formation of current sheets (CS) in different magnetic configurations, as well as the magnetic reconnection phenomena. In 2D magnetic fields with null-lines the CS formation was shown to be a typical process in both linear and nonlinear regimes. The problem of CS formation is of a fundamental importance in the general case of 3D magnetic configurations. We have revealed experimentally, that the formation of CS occurs in the various 3D configurations, both containing magnetic null-points and without them. At the same time, the CS parameters essentially depend on the local characteristics of the configuration. We may conclude therefore, that the self-organization of CS represents the universal process for the plasma dynamics in the nonuniform magnetic fields. (author)

  18. Operation of the APEX photoinjector accelerator at 40 MeV

    International Nuclear Information System (INIS)

    Feldman, D.W.; Bender, S.C.; Byrd, D.A.; Carlsten, B.E.; Early, J.W.; Feldman, R.B.; Goldstein, J.C.; Martineau, R.L.; O'Shea, P.G.; Pitcher, E.J.; Schmitt, M.J.; Stein, W.E.; Wilke, M.D.; Zaugg, T.J.

    1992-01-01

    We have successfully operated the photoinjector and rf linear accelerator for the Los Alamos APEX free electron laser (FEL) at design energy, average macropulse current, and emittance. The accelerator, which operates at 1.3 GHz, consists of a 6 MeV photoinjector and three standing-wave structures with a total beam energy of 40 MeV. This paper presents performance characteristics of the APEX system. The results show that this technology is capable of providing reliable, high-peak current, ultra-high brightness electron beams

  19. Lysimetric evaluation of the APEX Model to simulate daily ET for irrigated crops in the Texas High Plains

    Science.gov (United States)

    The NTT (Nutrient Tracking Tool) was designed to provide an opportunity for all users, including producers, to simulate the complex models, such as APEX (Agricultural Policy Environmental eXtender) and associated required databases. The APEX model currently nested within NTT provides estimates of th...

  20. Positional relationship between the maxillary sinus floor and the apex of the maxillary first molar using cone beam computed tomograph

    International Nuclear Information System (INIS)

    Kim, Kyung Hwa; Koh, Kwang Joon

    2008-01-01

    To assess the positional relationship between the maxillary sinus floor and the apex of the maxillary first molar using cone beam computed tomograph (CBCT). CBCTs from 127 subjects were analysed. A total of 134 maxillary first molars were classified according to their vertical and horizontal positional relationship to the maxillary sinus floor and measured according to the distance between the maxillary sinus floor and the maxillary first molar. Type III (The root projected laterally on the sinus cavity but its apex is outside the sinus boundaries) was dominated between 10 and 19 years and type I (The root apex was not in contact with the cortical borders of the sinus) was dominated (P<0.05) between 20 and 72 years on the vertical relationship between the maxillary sinus floor and the apex of the maxillary first molar. The maxillary sinus floor was located more at the apex (78.2%) than at the furcation (21.3%) for the palatal root. The distance from the root apex to the maxillary sinus floor confined to type I was increased according to the ages (P<0.05). Type M (The maxillary sinus floor was located between the buccal and the palatal root) was most common (72.4%) on the horizontal relationship between the maxillary sinus floor and the apex of the maxillary first molar. CBCT can provide highly qualified images for the maxillary sinus floor and the root apex of the maxillary first molar.

  1. Comparison of tentative radiographic working length with and without grid versus electronic apex locator

    Directory of Open Access Journals (Sweden)

    Tanikonda Rambabu

    2018-01-01

    Full Text Available The apical termination of obturation is the most important factor influencing the success of root canal treatment (RCT. Working length (WL is the key element in achieving this. Aim: The aim of this study is to compare and evaluate the preoperative estimated WL with conventional radiograph and with grid radiograph, with reference to electronic apex locator (EAL in single-rooted teeth. Settings and Design: Thirty permanent anterior teeth with complete root formation indicated for RCT were included in this study. Materials and Methods: Conventional radiograph (Group 1 and conventional radiograph with external grid (Group 2 were made before access opening. WL with EAL (Group 3 was determined after access opening. Statistical Analysis: The statistical package for the social sciences (SPSS version 16.0 (SPSS Inc., Chicago, IL, USA was used to compare the WLs of three groups, and the statistical significance was considered to be P ≤ 0.05. ANOVA, post hoc test were made to measure the intergroup comparison, and Pearson correlation values were obtained. Results and Conclusion: The results of the study showed a higher correlation between grid WL and apex locator WL than conventional WL and apex locator WL. Preoperative metrics with radiographic grid along with the apex locator is a better measuring tool compared to the conventional radiographic WL in a single-rooted tooth.

  2. Electron microscopy using the genetically encoded APEX2 tag in cultured mammalian cells

    Science.gov (United States)

    Martell, Jeffrey D; Deerinck, Thomas J; Lam, Stephanie S; Ellisman, Mark H; Ting, Alice Y

    2018-01-01

    Electron microscopy (EM) is the premiere technique for high-resolution imaging of cellular ultrastructure. Unambiguous identification of specific proteins or cellular compartments in electron micrographs, however, remains challenging because of difficulties in delivering electron-dense contrast agents to specific subcellular targets within intact cells. We recently reported enhanced ascorbate peroxidase 2 (APEX2) as a broadly applicable genetic tag that generates EM contrast on a specific protein or subcellular compartment of interest. This protocol provides guidelines for designing and validating APEX2 fusion constructs, along with detailed instructions for cell culture, transfection, fixation, heavy-metal staining, embedding in resin, and EM imaging. Although this protocol focuses on EM in cultured mammalian cells, APEX2 is applicable to many cell types and contexts, including intact tissues and organisms, and is useful for numerous applications beyond EM, including live-cell proteomic mapping. This protocol, which describes procedures for sample preparation from cell monolayers and cell pellets, can be completed in 10 d, including time for APEX2 fusion construct validation, cell growth, and solidification of embedding resins. Notably, the only additional steps required relative to a standard EM sample preparation are cell transfection and a 2- to 45-min staining period with 3,3′-diaminobenzidine (DAB) and hydrogen peroxide (H2O2). PMID:28796234

  3. Petrous apex chordoma - a case report; Cordoma de apice petroso - relato de um caso

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Claudio Regis S. [Clinica Boghos Boyadjian, Fortaleza, CE (Brazil); Barreto, Cristina Marques; Rossi, Luis Antonio [Hospital do Servidor Publico Estadual de Sao Paulo, SP (Brazil). Servico de Radiologia; Michiloski, Custodio; Rotta, Jose Marcus [Hospital do Servidor Publico Estadual de Sao Paulo, SP (Brazil). Servico de Neurocirurgia; Almeida, Serguey Malaquias de

    2001-02-01

    Chordomas are rare neoplasms arising from notochordal remnants that persist along the axial skeleton. Intracranial chordomas occur more frequently in the midline. We describe a typical case of an off-midline chordoma arising from the petrous apex, and discuss the embryogenic factors which determine that location, as well as the symptoms, imaging findings, surgical treatment and evolution. (author)

  4. Apex simulation: environmental benefits of agroforestry and grass buffers for corn-soybean watersheds

    Science.gov (United States)

    The Agricultural Policy Environmental Extender (APEX) model is used to simulate the effects of vegetative filter strips on runoff and pollutant loadings from agricultural watersheds. A long-term paired watershed study under corn (Zea mays L-soybean [Glycine max (L.) Merr.] rotation with agroforestr...

  5. Code modernization and modularization of APEX and SWAT watershed simulation models

    Science.gov (United States)

    SWAT (Soil and Water Assessment Tool) and APEX (Agricultural Policy / Environmental eXtender) are respectively large and small watershed simulation models derived from EPIC Environmental Policy Integrated Climate), a field-scale agroecology simulation model. All three models are coded in FORTRAN an...

  6. APEX (Air Pollution Exercise) Volume 21: Legal References: Air Pollution Control Regulations.

    Science.gov (United States)

    Environmental Protection Agency, Research Triangle Park, NC. Office of Manpower Development.

    The Legal References: Air Pollution Control Regulations Manual is the last in a set of 21 manuals (AA 001 009-001 029) used in APEX (Air Pollution Exercise), a computerized college and professional level "real world" game simulation of a community with urban and rural problems, industrial activities, and air pollution difficulties. The manual…

  7. VizieR Online Data Catalog: APEX CO and HI observations of Lupus I (Gaczkowski+, 2017)

    Science.gov (United States)

    Gaczkowski, B.; Roccatagliata, V.; Flaischlen, S.; Kroell, D.; Krause, M. G. H. Burkert A.; Diehl, R.; Fierlinger, K.; Ngoumou, J.; Preibisch, T.

    2017-11-01

    The FITS files contain the data cubes corresponding to the 13C and C18O(3-2) lines. They were taken using the Atacama Pathfinder EXperiment (APEX) telescope, with an angular resolution of 30" and a velocity resolution of 0.1km/s. (2 data files).

  8. 76 FR 13663 - Cooper Tools, Currently Known as Apex Tool Group, LLC, Hicksville, OH; Amended Certification...

    Science.gov (United States)

    2011-03-14

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-71,652] Cooper Tools, Currently... Adjustment Assistance on April 27, 2010, applicable to workers of Cooper Tools, Hicksville, Ohio. The workers.... purchased Cooper Tools and is currently known as Apex Tool Group, LLC. Some workers separated from...

  9. Development of a sensitivity and uncertainty analysis tool in R for parametrization of the APEX model

    Science.gov (United States)

    Hydrologic models are used to simulate the responses of agricultural systems to different inputs and management strategies to identify alternative management practices to cope up with future climate and/or geophysical changes. The Agricultural Policy/Environmental eXtender (APEX) is a model develope...

  10. Modeling conservation practices in APEX: From the field to the watershed

    Science.gov (United States)

    The evaluation of USDA conservation programs is required as part of the Conservation Effects Assessment Project (CEAP). The Agricultural Policy/Environmental eXtender (APEX) model was applied to the St. Joseph River Watershed, one of CEAP’s benchmark watersheds. Using a previously calibrated and val...

  11. Framework to parameterize and validate APEX to support deployment of the nutrient tracking tool

    Science.gov (United States)

    Guidelines have been developed to parameterize and validate the Agricultural Policy Environmental eXtender (APEX) to support the Nutrient Tracking Tool (NTT). This follow-up paper presents 1) a case study to illustrate how the developed guidelines are applied in a headwater watershed located in cent...

  12. Impact of APEX parameterization and soil data on runoff, sediment, and nutrients transport assessment

    Science.gov (United States)

    Hydrological models have become essential tools for environmental assessments. This study’s objective was to evaluate a best professional judgment (BPJ) parameterization of the Agricultural Policy and Environmental eXtender (APEX) model with soil-survey data against the calibrated model with either ...

  13. State of science of phosphorus modeling in tile drained agricultural systems using APEX

    Science.gov (United States)

    Phosphorus losses through tile drained systems in agricultural landscapes may be causing the persistent eutrophication problems observed in surface water. The purpose of this paper is to evaluate the state of the science in the Agricultural Policy/Environmental eXtender (APEX) model related to surf...

  14. APEX model simulation of edge-of-field water quality benefits from upland buffers

    Science.gov (United States)

    For maximum usefulness, simulation models must be able to estimate the effectiveness of management practices not represented in the dataset used for model calibration. This study focuses on the ability of the Agricultural Policy Environmental eXtender (APEX) to simulate upland buffer effectiveness f...

  15. Combined PEST and Trial-Error approach to improve APEX calibration

    Science.gov (United States)

    The Agricultural Policy Environmental eXtender (APEX), a physically-based hydrologic model that simulates management impacts on the environment for small watersheds, requires improved understanding of the input parameters for improved simulations. However, most previously published studies used the ...

  16. In vitro selection of rape variants resistant to oxalic acid using haploid stem apexes

    International Nuclear Information System (INIS)

    Wang Yifei; Huang Jianhua; Lu Ruiju; Sun Yuefang; Zhou Runmei; Zhou Zhijiang; Xie Zhujie; Liu Chenghong

    2002-01-01

    Mutagenic treatment was made of the haploid stem apexes rape strain '9841' and '9885' with Pingyangmycin. As a result of positive selection with oxalic acid providing selection pressure, variants with significantly higher tolerance to oxalic acid than the original ones were obtained. 3 germplasm with significantly higher resistance to Sclerotinia sclerotiorum than cultivar Hu You 12 were selected from field test

  17. Functional Polymorphisms of Base Excision Repair Genes XRCC1 and APEX1 Predict Risk of Radiation Pneumonitis in Patients With Non-Small Cell Lung Cancer Treated With Definitive Radiation Therapy

    International Nuclear Information System (INIS)

    Yin Ming; Liao Zhongxing; Liu Zhensheng; Wang, Li-E; Gomez, Daniel; Komaki, Ritsuko; Wei Qingyi

    2011-01-01

    Purpose: To explore whether functional single nucleotide polymorphisms (SNPs) of base-excision repair genes are predictors of radiation treatment-related pneumonitis (RP), we investigated associations between functional SNPs of ADPRT, APEX1, and XRCC1 and RP development. Methods and Materials: We genotyped SNPs of ADPRT (rs1136410 [V762A]), XRCC1 (rs1799782 [R194W], rs25489 [R280H], and rs25487 [Q399R]), and APEX1 (rs1130409 [D148E]) in 165 patients with non-small cell lung cancer (NSCLC) who received definitive chemoradiation therapy. Results were assessed by both Logistic and Cox regression models for RP risk. Kaplan-Meier curves were generated for the cumulative RP probability by the genotypes. Results: We found that SNPs of XRCC1 Q399R and APEX1 D148E each had a significant effect on the development of Grade ≥2 RP (XRCC1: AA vs. GG, adjusted hazard ratio [HR] = 0.48, 95% confidence interval [CI], 0.24-0.97; APEX1: GG vs. TT, adjusted HR = 3.61, 95% CI, 1.64-7.93) in an allele-dose response manner (Trend tests: p = 0.040 and 0.001, respectively). The number of the combined protective XRCC1 A and APEX1 T alleles (from 0 to 4) also showed a significant trend of predicting RP risk (p = 0.001). Conclusions: SNPs of the base-excision repair genes may be biomarkers for susceptibility to RP. Larger prospective studies are needed to validate our findings.

  18. First test results of the airborne dispersive pushbroom imaging spectrometer APEX

    Science.gov (United States)

    Meuleman, K.; Itten, K.; Schaepman, M.

    2009-04-01

    APEX, ESA-Prodex "Airborne Prism Experiment" comprises the development of an airborne dispersive pushbroom imaging spectrometer and has originally been designed as flexible hyperspectral mission simulator and calibrator for existing and upcoming or planned future space missions. The APEX project is co-funded by Switzerland and Belgium and built by a Belgian-Swiss industrial team under the prime RUAG Aerospace (CH), responsible for the total system and the mechanical components, OIP (Oudenaarde, BE) contributing the spectrometer, and Netcetera (Zurich, CH) being responsible for the electronics. RSL (University of Zurich, CH) acts as scientific PI together with the Co-PI VITO (Mol, BE). The APEX sensor is operating between 380 nm and 2500 nm in more than 300 freely configurable bands (up to 512 bands in full spectral mode), by means of two dispersive spectrometer channels. 1000 pixels across track and a total field of view of 28° define the ground pixel size (e.g. 2,5 m from 5000 m AGL). A stabilized platform (Leica PAV-30) reduces major geometric distortions due to aircraft instabilities while a GPS/IMU system (Applanix PosAV 410) measures continuously the sensors' position and orientation allowing direct georeferencing of the acquired data . The system is currently is phase D, the calibration and test phase, and first testflights have been performed on a Do-228 in cooperation of DLR while the acquired data is currently under evaluation. Discussions are ongoing to fly APEX on the new DLR High Altitude Research Aircraft (HALO) as well. The system is currently in phase D, the calibration and test phase, and will deliver first scientific data to users by mid 2009. The APEX processing and archiving facility (PAF) is hosted by VITO in the APEX Operations Center (AOC) at Mol, Belgium . A specific level 0-1 processing software module producing uniform, radiometrically calibrated data has been developed by RSL and is integrated into the PAF by VITO. An APEX Calibration

  19. High-power plasma dynamic systems of quasi-stationary type in IPP NSK KIPT: results and prospects

    International Nuclear Information System (INIS)

    Solyakov, D.G.

    2015-01-01

    This paper is devoted to brief review of main experimental results of investigations of high-power quasi-stationary plasma dynamic systems in the IPP NSC KIPT. In experiments were shown that to received accelerated plasma streams with high value of energy in quasi-stationary modes all conditions on the accelerating channel boundary should be controlled independently. As a results of optimizations of the modes of operation all QSPA active elements quasi-stationary plasma flow in the channel during 480 μs at discharge durations 550μs was obtained. The plasma streams velocity was close to theoretical limit for present experimental conditions. Plasma streams with maximum velocity up to 4.2 · 10 7 cm/s and total value of energy containment in the stream 0.4...0.6 MJ were received. The main properties of compression zone formation in the plasma streams generated by magneto-plasma compressor in quasi-stationary modes were investigated. In experiments were shown that initial conditions, namely residual pressure in the vacuum chamber made a big influence on the value of plasma density in compression zone. Compressive plasma streams with density (2...4)·10 18 cm -3 during 20...25μs at discharge duration 10μs were obtained. This value of plasma density is close to theoretical limit for present experimental conditions

  20. Oregon state university's advanced plant experiment (APEX) AP1000 integral facility test program

    International Nuclear Information System (INIS)

    Reyes, J.N.; Groome, J.T.; Woods, B.G.; Young, E.; Abel, K.; Wu, Q.

    2005-01-01

    Oregon State University (OSU) has recently completed a three year study of the thermal hydraulic behavior of the Westinghouse AP1000 passive safety systems. Eleven Design Basis Accident (DBA) scenarios, sponsored by the U.S. Department of Energy (DOE) with technical support from Westinghouse Electric, were simulated in OSU's Advanced Plant Experiment (APEX)-1000. The OSU test program was conducted within the purview of the requirements of 10CFR50 Appendix B, NQA-1 and 10 CFR 21 and the test data was used to provide benchmarks for computer codes used in the final design approval of the AP1000. In addition to the DOE certification testing, OSU conducted eleven confirmatory tests for the U.S. Nuclear Regulatory Commission. This paper presents the test program objectives, a description of the APEX-1000 test facility and an overview of the test matrix that was conducted in support of plant certification. (authors)

  1. A case of orbital apex syndrome due to Pseudomonas aeruginosa infection

    Directory of Open Access Journals (Sweden)

    Takeshi Kusunoki

    2011-11-01

    Full Text Available Orbital apex syndrome is commonly been thought to have a poor prognosis. Many cases of this syndrome have been reported to be caused by paranasal sinus mycosis. We encountered a very rare case (60-year-old woman of sinusitis with orbital apex syndrome due to Pseudomonas aeruginosa infection. She had received insulin and dialysis for diabtes and diabetic nephropathy, moreover anticoagulants after heart by-pass surgery. She underwent endoscopic sinus operation and was treated with antibiotics, but her loss of left vision did not improve. Recently, sinusitis cases due to Pseudomonas aeruginosa were reported to be a increasing. Therefore, we should consider the possibility of Pseudomonas aeruginosa as well as mycosis as infections of the sinus, especially inpatients who are immunocompromised body.

  2. Wear simulation of apex seal in rotary engine under mixed lubrication

    Science.gov (United States)

    Jiang, Hanying; Zuo, Zhengxing; Liu, Jinxiang

    2018-05-01

    In this work, the wear of apex seal's running face under mixed lubrication is studied. Numerical simulation is carried out by employing the couple model of Reynolds equation, Greenwood and Tripp model and Archard's wear law. The simulation is performed both for one circle and multi circle. In the multi circle simulation, the change of contact position due to wear is considered. A method that is able to find the new contact position based on the updated apex seal's contour profile is proposed, validated and used. The result of multi circle simulation indicates that contact position changes obviously around the maximum swing angles both on leading and trailing sides with the increase number of circles. The wear depth distribution becomes more uniform with the increase of operation circle number.

  3. A Numerical Study on Premixed Bluff Body Flame of Different Bluff Apex Angle

    Directory of Open Access Journals (Sweden)

    Gelan Yang

    2013-01-01

    Full Text Available In order to investigate effects of apex angle (α on chemically reacting turbulent flow and thermal fields in a channel with a bluff body V-gutter flame holder, a numerical study has been carried out in this paper. With a basic geometry used in a previous experimental study, the apex angle was varied from 45° to 150°. Eddy dissipation concept (EDC combustion model was used for air and propane premixed flame. LES-Smagorinsky model was selected for turbulence. The gird-dependent learning and numerical model verification were done. Both nonreactive and reactive conditions were analyzed and compared. The results show that as α increases, recirculation zone becomes bigger, and Strouhal number increases a little in nonreactive cases while decreases a little in reactive cases, and the increase of α makes the flame shape wider, which will increase the chamber volume heat release ratio and enhance the flame stability.

  4. Chordoma of the petrous apex - a case report and review of the literature

    International Nuclear Information System (INIS)

    Loureiro, Ricardo; Leal Junior, Osvaldo S.; Loureiro, Lautonio Junior; Buril, Marlus V.M.

    1998-01-01

    Chordomas are rare tumours arising from remnants of the embryologic notochord, typically at a midline position. Although 35-40% of these lesions are intracranial, these tumors answer for less than 1% of all intracranial tumors. The intracranial chordomas originate most frequently from the clival region at the midline. Nevertheless eventually may arise off the midline primarily in petrous apex or, very rarely, in paranasal sinuses. The authors report a case of histopathologically proved intracranial chordoma that arose atypical site in the petrous apex. The computed tomographic and magnetic resonance imaging finding were similar to those observed in midline chordomas. The computed tomographic examination revealed a well-defined soft tissue mass associated with bone destruction and foci of calcification. The magnetic resonance imaging study demonstrated a growing extra-axial formation that appeared with hypo-intensity of signal on T1-weighted images, hyperintensity on T2-weighted images and heterogeneous enhancement after paramagnetic agent injection. (author)

  5. Effects of Dissolving Solutions on the Accuracy of an Electronic Apex Locator-Integrated Endodontic Handpiece

    Directory of Open Access Journals (Sweden)

    Yakup Ustun

    2013-01-01

    Full Text Available The effects of three dissolving agents on the accuracy of an electronic apex locator- (EAL- integrated endodontic handpiece during retreatment procedures were evaluated. The true lengths (TLs of 56 extracted incisor teeth were determined visually. Twenty teeth were filled with gutta-percha and a resin-based sealer (group A, 20 with gutta-percha and a zinc oxide/eugenol-based sealer (group B, and 16 roots were used as the control group (group C. All roots were prepared to TL. Guttasolv, Resosolv, and Endosolv E were used as the dissolving solutions. Two evaluations of the handpiece were performed: the apical accuracy during the auto reverse function (ARL and the apex locator function (EL alone. The ARL function of the handpiece gave acceptable results. There were significant differences between the EL mode measurements and the TL (P<0.05. In these comparisons, Tri Auto ZX EL mode measurements were significantly shorter than those of the TL.

  6. [Orbital apex syndrome of the aspergillus etiology--a case report].

    Science.gov (United States)

    Fric, E; Rehák, M; Vlcková, I; Burval, S; Chrapek, O; Rehák, J

    2007-04-01

    The authors present a case report of a patient, in whom after a head injury the monolateral blindness occurred. Because of autoimmune thrombocytopeny the patient was treated with long-term corticosteroids. The clinical findings corresponded with the orbital apex syndrome. According to the results of the CT and MRI examinations, the sphenoidotomy was indicated, and the histological findings verified fragments of paranasal sinuses' aspergiloma. During the next course of the disease, despite antimycotic therapy, the progression of the aspergiloma in to the anterior cranial fossa occurred. Invasive sino-orbital aspergilosis, after the penetration of the infectious agent across the wall of the sinus, may cause the orbital apex syndrome with paralysis of all three cranial nerves innervating the extraocular muscles, sensoric defect in the area of the ophthalmic nerve and the involvement of the optic nerve.

  7. Management of persistent periapical infection on maxillary lateral incisorby apex resection of: A case report

    Directory of Open Access Journals (Sweden)

    Yusri Yusri

    2016-06-01

    Full Text Available Endodontic failure can be caused by different etiology, one of them is a persistent periapical infection in the root canal system. If the endodontic convensional retreatment is difficult to be done, surgical endodontic will be recomended. Endodontic surgical can eliminate the causative agent of periradicular disease and to restore the biological condition of periodontium and functional. A 22 years old male patient came to the Dental Hospital Hasanuddin University at Tamalanrea with the chief complaint is discomfort of the left maxillary lateral incisor. Radiograph examinations showed radiolucency 4 mm of tooth 22. The diagnosis is chronic apical periodontitis.Three month after endodontic conventional, the patients complaint is settled. Extended care plan will be treated is apex resection. The purpose of this case report is to present the treatment protocol of apex resection on  the maxillary left lateral incisor.

  8. Accuracy of a fourth generation apex locator-an in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Dalia Abdullah

    2007-09-01

    Full Text Available The new fourth generation electronic apex locator (EAL, Elements (SybronEndo, USA has been introduced recently in the market. This study aims to investigate the accuracy of this EAL and to compare the result with a well-known apex locator, Root ZX and the radiographic technique using an in vitro model. Thirty anterior teeth with straight canals stored in 10% formalin were used. Access cavities were prepared followed by coronal flaring of the canals. Water was used as an irrigant. After the actual lengths (AL were measured, the teeth were then embedded in an alginate model. Periapical radiograph of each tooth was taken using a digital sensor and the radiographic lengths (RL were measured 0.5 mm short of the radiographic apex. Electronic tooth length measurements (EL were carried out using both EAL. Canals were then irrigated with 2.5% NaOCl and EL was taken again. Results showed that both EALs were highly accurate to within + 0.5 mm of the apical foramen, with mean differences between the AL and EL of Elements 0.23mm (SE = 0.04 and Root ZX was 0.31mm (SE = 0.05. RL was significantly less accurate compared to the readings from both EAL. No significant difference was found in the reading between both apex locators when measurements were taken in NaOCl solution. Both Elements and Propex proved to be as reliable as Root ZX. Presence of sodium hypochlorite solution did not affect the accuracy of the measurements.

  9. Evaluating Electromagnetic Interference of Communication Devices with Root ZX Mini Apex Locator

    Directory of Open Access Journals (Sweden)

    Marzieh Shafieibavani

    2016-01-01

    Full Text Available Introduction: The correct determination of working length is a critical factor in the success of endodontic treatment. Nowadays, the electronic apex locators (EALs is more used because of their ease of use, high accuracy, and the uncertainty of other methods. Because EALs use the electronic method, it is likely that electromagnetic waves (EMWs affect their performance. This study aims to investigate the possibility of this interference. Materials and Methods: The visual canal length (CL of 12 maxillary incisors (Vertucci’s type I was measured with a K-file and magnifying glass. Root ZX mini apex locator is used to measure CL in the absence/presence of EMWs in both the second (2G and third generations (3G of mobile communication network at the mode of ringing and conversation at direct contact and the distances of 25 and 50 cm. Results: The mean CL at presence of EMWs in all conditions and distances (by removing the conversation with 2G at direct contact group were not significantly difference with CL and EAL and absence of investigated EMWs group (Repeated-Measures Analysis of Variance (ANOVA, P = 0.083. The indicator of EAL were unstable on apex sign at least 5 seconds for 5 teeth (41.7% of samples in conversation with 2G at the direct contact group. Conclusion: EMWs of 2G and 3G not causes malfunctions of the Root ZX mini apex locator except conversation with 2G at the direct contact.

  10. Interference of apex locator, pulp tester and diathermy on pacemaker function.

    Science.gov (United States)

    Sriman, Narayanan; Prabhakar, V; Bhuvaneswaran, J S; Subha, N

    2015-01-01

    The purpose of this study was to evaluate the effects of three electronic apex locators (EAL), electric pulp tester (EPT) and diathermy on pacemaker function in vitro. Three EALs: Root ZX (J. Morita Co., Tustin, CA, U.S.A.), Propex (Dentsply), Mini Apex locator (SybronEndo, Anaheim, CA, USA), EPT (Parkell pulp vitality tester Farmingdale, NY, USA) and Diathermy (Neomed 250 B) were tested for any interference with one pacemaker (A medtronic kappa KVDD901-serial number: PLE734632S). Directly connecting the pacemaker lead with the EAL/EPT/diathermy operating on a flat bench top, the telemetry wand was held directly over the pacemaker to monitor the pacing pattern for a period of 30 s. Pacemaker activity was continuously recorded on the telemetric programmer and electro gram (EGM) readings examined for pacer inhibition, noise reversion or inappropriate pacemaker pulses. All the three apex locators showed no pacing interference or background noise during its function or at rest. The EGM readings of EPT showed varying levels of background noise in between pacing however, this did not affect the normal pacing pattern and the pacing interval remained constant. EGM readings of diathermy showed an increase in the pacing interval (irregular pacing pattern) followed by complete inhibition of the pacing system. The tested EALs do not interfere with cardiac pacemaker function. The tested EPT showed varying levels of background noise but does not interfere with cardiac pacemaker function. Use of Diathermy interfered with the normal pacing, leading to complete inhibition of the pacing system.

  11. Radioelectric asymmetric brain stimulation and lingual apex repositioning in patients with atypical deglutition

    Directory of Open Access Journals (Sweden)

    Castagna A

    2011-06-01

    Full Text Available Alessandro Castagna1, Salvatore Rinaldi1,2, Vania Fontani1, Piero Mannu11Rinaldi-Fontani Institute, 2School of Occupational Medicine, University of Florence, Florence, ItalyBackground: Atypical deglutition is exacerbated by stress and anxiety. Several therapeutic approaches have been employed to treat stress and anxiety disorders, ranging from typical psychopharmacological strategies to novel physical protocols, such as transcranial magnetic stimulation and radioelectric asymmetric conveyor (REAC stimulation. The purpose of the present study was to test the efficacy of REAC brain stimulation in atypical deglutition.Methods: The position of the lingual apex (Payne method, pattern of free deglutition, and subjective and objective impression of deglutition were evaluated in 128 outpatients suffering from atypical deglutition. Deglutition testing consisted of an operator holding down the lower lip, hence counteracting the strength exerted by the orbicularis muscle. All subjects were treated using two REAC brain stimulation protocols. Patients were assessed before treatment, immediately after treatment, and three months following the last cycle of REAC therapy.Results: REAC stimulation led to an improvement in positioning of the lingual apex and a significant decrease of muscle involvement in all patients immediately after REAC treatment, and the improvement was maintained at three-month follow-up.Conclusion: In the present study, the REAC therapeutic protocols led to normalization in lingual apex positioning and significant improvement in swallowing in all participants suffering from atypical deglutition.Keywords: atypical deglutition, stress, anxiety, radioelectric asymmetric brain stimulation

  12. Energy management that generates terrain following versus apex-preserving hopping in man and machine.

    Science.gov (United States)

    Kalveram, Karl Theodor; Haeufle, Daniel F B; Seyfarth, André; Grimmer, Sten

    2012-01-01

    While hopping, 12 subjects experienced a sudden step down of 5 or 10 cm. Results revealed that the hopping style was "terrain following". It means that the subjects pursued to keep the distance between maximum hopping height (apex) and ground profile constant. The spring-loaded inverse pendulum (SLIP) model, however, which is currently considered as template for stable legged locomotion would predict apex-preserving hopping, by which the absolute maximal hopping height is kept constant regardless of changes of the ground level. To get more insight into the physics of hopping, we outlined two concepts of energy management: "constant energy supply", by which in each bounce--regardless of perturbations--the same amount of mechanical energy is injected, and "lost energy supply", by which the mechanical energy that is going to be dissipated in the current cycle is assessed and replenished. When tested by simulations and on a robot testbed capable of hopping, constant energy supply generated stable and robust terrain following hopping, whereas lost energy supply led to something like apex-preserving hopping, which, however, lacks stability as well as robustness. Comparing simulated and machine hopping with human hopping suggests that constant energy supply has a good chance to be used by humans to generate hopping.

  13. Plasma dynamic synthesis and obtaining ultrafine powders of iron oxides with high content of ε-Fe2O3

    Science.gov (United States)

    Sivkov, Alexander; Naiden, Evgenii; Ivashutenko, Alexander; Shanenkov, Ivan

    2016-05-01

    The ultrafine iron oxide powders were successfully synthesized using the plasma dynamic synthesis method, based on the use of a coaxial magnetoplasma accelerator with the iron electrode system. The synthesis was implemented in the high-speed iron-containing plasma jet, flowing into the space of the sealed chamber, filled with the gaseous mixture of oxygen and argon at different ratios. The XRD investigations showed that the synthesized products were heterophase and consisted of three main phases such as magnetite Fe3O4, hematite α-Fe2O3 and ε-Fe2O3. The SEM data confirmed the presence of three particle types: the hollow spheroids with sizes about hundreds of micrometers (magnetite), the particles with sizes up to 100 μm from the porous material of sintered submicron particles (hematite), and nanoscale particles (ε-phase). We found that at the higher oxygen concentration the content of ε-Fe2O3 is increased up to 50% at the same time with decreasing the Fe3O4 phase. The magnetic properties of the products are mainly determined by magnetite characteristics and are significantly reduced with decreasing its content in the powder. In order to investigate the synthesized ε-Fe2O3 on the ability to absorb the electromagnetic radiation in the millimeter wavelength range, we separated the product with the higher ε-phase concentration. The fraction mainly, consisting of ε-Fe2O3, showed the occurrence of the natural resonance at frequencies of 8.3 GHz and 130 GHz.

  14. Study on the treatment of traumatic orbital apex syndrome by nasal endoscopic surgery.

    Science.gov (United States)

    Li, Youzhong; Wu, Weijing; Xiao, Zian; Peng, Anquan

    2011-03-01

    Orbital apex syndrome (OAS) is a complex disease caused by a variety of pathological factors, and trauma is one of the main factors/causes. Clinical data of 17 cases of traumatic OAS treated by nasal endoscopic surgery in our department from January 2002 to April 2009 were gathered and reviewed. Among them, the six patients presented with OAS after injury to the lateral wall of orbital apex. Seven other patients exhibited OAS after injury to the medial wall of orbital apex, two displayed OAS after zygomatic trauma, while OAS manifested in the other two patients with craniocerebral trauma 3 days after they had decompressive craniotomy--of them, one was blind in both eyes. In the 17 cases, 6 patients were without light sensation, 1 was blind in both eyes; the sight-chart index of eight patients was 0.1, that of three other patients was 0.1-0.2. Fifteen patients displayed eyeball movement disturbance (disorder) and cornea sensory disturbance (disorder), two were with the eyeball abducent disturbance. After the nasal endoscopic surgeries for OAS performed on the 17, the sight of the most patients was restored in varying degrees. The sight of nine patients was between 0.2 and 0.3, that of two patients was between 0.1 and 0.2, that of the other two patients was 0.1, and that of four patients remained unchanged. The eyeball movement and the cornea esthesia in 15 patients recovered from the surgeries, one patient recovered with good eyeball adducent movement and the cornea esthesia but with eyeball abducent disturbance, the other patient did not make a recovery from the eyeball immobility, cornea anesthesia and ptosis. A follow-up lasting 2 months to 2 years suggested that the 16 patients had stable recovery from the surgeries. Satisfactory results could be achieved in the treatment of traumatic OAS by nasal endoscopic surgery. From objective assessment of the therapeutic effects of traumatic OAS, it can be concluded that if a patient is diagnosed with fractures of the

  15. Prepartum teat apex colonization with Staphylococcus chromogenes in dairy heifers is associated with low somatic cell count in early lactation.

    Science.gov (United States)

    De Vliegher, S; Laevens, H; Devriese, L A; Opsomer, G; Leroy, J L M; Barkema, H W; de Kruif, A

    2003-04-02

    A high number of dairy heifers freshen with udder health problems. The prevalence of teat apex colonization (TAC) with Staphylococcus chromogenes, one of the most widespread coagulase-negative staphylococci (CNS) in milk samples from freshly calved dairy heifers, was measured cross-sectionally in non-lactating heifers on eight commercial dairy farms in Belgium. The influence of age on this prevalence, and the association between teat apex colonization with S. chromogenes prepartum and quarter milk somatic cell count (SCC) in early lactation were studied. In total, 492 teat apices were sampled from 123 heifers. The age of the heifers varied from 8 to 34 months. Overall, 20% of the heifers had at least one teat apex colonized with S. chromogenes. Of all teats sampled, 10% were colonized with S. chromogenes. The chance of having at least one teat apex colonized with S. chromogenes increased with age of the heifer. The presence of prepartum teat apex colonization with S. chromogenes was not associated with intramammary infection (IMI) early postpartum with the same bacterium. On the contrary, teat apex colonization with S. chromogenes prepartum appeared to protect quarters in the first few days of lactation from having somatic cell count >or=200000cells/ml milk, commonly accepted as the threshold for intramammary infection.

  16. ATTENUATION OF DIFFRACTED MULTIPLES WITH AN APEX-SHIFTED TANGENT-SQUARED RADON TRANSFORM IN IMAGE SPACE

    Directory of Open Access Journals (Sweden)

    Alvarez Gabriel

    2006-12-01

    Full Text Available In this paper, we propose a method to attenuate diffracted multiples with an apex-shifted tangent-squared Radon transform in angle domain common image gathers (ADCIG . Usually, where diffracted multiples are a problem, the wave field propagation is complex and the moveout of primaries and multiples in data space is irregular. The method handles the complexity of the wave field propagation by wave-equation migration provided that migration velocities are reasonably accurate. As a result, the moveout of the multiples is well behaved in the ADCIGs. For 2D data, the apex-shifted tangent-squared Radon transform maps the 2D space image into a 3D space-cube model whose dimensions are depth, curvature and apex-shift distance.
    Well-corrected primaries map to or near the zero curvature plane and specularly-reflected multiples map to or near the zero apex-shift plane. Diffracted multiples map elsewhere in the cube according to their curvature and apex-shift distance. Thus, specularly reflected as well as diffracted multiples can be attenuated simultaneously. This approach is illustrated with a segment of a 2D seismic line over a large salt body in the Gulf of Mexico. It is shown that ignoring the apex shift compromises the attenuation of the diffracted multiples, whereas the approach proposed attenuates both the specularly-reflected and the diffracted multiples without compromising the primaries.

  17. Evaluation of the APEX Model to Simulate Runoff Quality from Agricultural Fields in the Southern Region of the United States.

    Science.gov (United States)

    Ramirez-Avila, John J; Radcliffe, David E; Osmond, Deanna; Bolster, Carl; Sharpley, Andrew; Ortega-Achury, Sandra L; Forsberg, Adam; Oldham, J Larry

    2017-11-01

    The Agricultural Policy Environmental eXtender (APEX) model has been widely applied to assess phosphorus (P) loss in runoff water and has been proposed as a model to support practical decisions regarding agricultural P management, as well as a model to evaluate tools such as the P Index. The aim of this study is to evaluate the performance of APEX to simulate P losses from agricultural systems to determine its potential use for refinement or replacement of the P Index in the southern region of the United States. Uncalibrated and calibrated APEX model predictions were compared against measured water quality data from row crop fields in North Carolina and Mississippi and pasture fields in Arkansas and Georgia. Calibrated models satisfactorily predicted event-based surface runoff volumes at all sites (Nash-Sutcliffe efficiency [NSE] > 0.47, |percent bias [PBIAS]| < 34) except Arkansas (NSE < 0.11, |PBIAS| < 50) but did not satisfactory simulate sediment, dissolved P, or total P losses in runoff water. The APEX model tended to underestimate dissolved and total P losses from fields where manure was surface applied. The model also overestimated sediments and total P loads during irrigation events. We conclude that the capability of APEX to predict sediment and P losses is limited, and consequently so is the potential for using APEX to make P management recommendations to improve P Indices in the southern United States. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  18. Geospace Plasma Dynamics

    Science.gov (United States)

    2013-05-22

    perturbations. High-speed solar wind streams cause recurrent geomagnetic activity and ionospheric disturbances. In [5], we analyze the equatorial...over eight successive orbits (~12 hours). A clear pre- reversal enhancement of upward plasma drift occurred between 18:00 and 19:00 LT when plasma

  19. General Relativistic Plasma Dynamics

    NARCIS (Netherlands)

    Moortgat, J.B.

    2006-01-01

    In this thesis I discuss the importance of general relativity on plasma physics in several astrophysical and cosmological contexts. The first chapters show how gravitational waves can excite all three fundamental low frequency magnetohydrodynamic plasma modes, the Alfven, slow and fast

  20. Curative high dose rate vaginal apex brachytherapy in stage I papillary serous carcinoma of the endometrium

    International Nuclear Information System (INIS)

    Turner, B.C.; Kacinski, B.M.; Gumbs, A.; Peschel, R.E.; Haffty, B.G.; Wilson, L.D.

    1996-01-01

    Introduction: Uterine papillary serous carcinoma (UPSC) is a morphologically distinct variant of endometrial carcinoma that is associated with a poor prognosis, high recurrence rate, clinical understaging, and poor response to salvage treatment. We describe the presentation, local and distant control, survival, salvage rate, and complications for patients undergoing whole abdominal radiation therapy (WART), low dose rate (LDR) intracavitary brachytherapy, or high dose rate (HDR) vaginal brachytherapy in patients with stage I UPSC. Methods: Between 1976 and 1994 more than 1700 patients with endometrial carcinoma were treated with radiation therapy, 30 patients with stage I UPSC (1.8%) were treated with radiation before or following TAH/BSO. All patients underwent either preoperative Simon's packing or tandem and plaque which delivered 30-40 Gy to the serosa, WART, or HDR Ir-192 vaginal apex brachytherapy to a total dose of 21 Gy in 3 fractions at 0.5 cm from the vaginal mucosa. A total of 14 patients received HDR vaginal brachytherapy and (5(14)) patients received systemic chemotherapy. All patients presented with vaginal bleeding at a median age of 67 years (range 34-88). The group of 30 patients underwent TAH/BSO, 17 patients were completely staged pathologically (pelvic and para-aortic lymph nodes, omentectomy, and pelvic washings), and 2 patients underwent omental biopsy and pelvic washings only. All specimens revealed UPSC, nuclear grade 3, and lymphovascular invasion (23%). The pathologic stage was IA: 23% (7), IB: 67% (20), and IC: 10% (3). The median follow-up for all patients was 49 months (range 13-187 months). For the patients receiving postoperative HDR vaginal brachytherapy the median time from surgery to radiation was 42 days (range 29-91). Results: The 5-year actuarial disease free survival for Figo stage I UPSC patients treated with postoperative HDR vaginal brachytherapy and systemic chemotherapy was 100% compared to 74% for stage I UPSC patient

  1. Post-operative high dose rate vaginal apex brachytherapy in stage I endometrial adenocarcinoma

    International Nuclear Information System (INIS)

    Gumbs, A.A.; Turner, B.C.; Knisely, J.P.S.; Kacinski, B.M.; Roberts, K.B.; Peschel, R.E.; Haffty, B.G.; Rutherford, T.J.; Edraki, B.; Schwartz, P.E.; Wilson, L.D.

    1996-01-01

    Purpose/Objective: Patients with Stage I endometrial adenocarcinoma have traditionally been treated with total abdominal hysterectomy/bilateral salpingo-oophorectomy and radiation. The reported incidence of local recurrence in surgically treated patients with FIGO Stage IA or IB endometrial adenocarcinoma is 4-10% at 2 years. Combined surgery and radiation has resulted in a reduction of recurrence to 2-6%. We report the presentation, actuarial survival, actuarial rate of local failure, salvage rate, and complications for patients undergoing high dose rate (HDR) vaginal apex brachytherapy following surgery. Materials and Methods: Between 1985 and 1994 a total of 286 patients with FIGO Stage I endometrioid uterine adenocarcinoma were treated with HDR Ir-192 vaginal apex brachytherapy alone to a total dose of 21 Gy in 3 fractions at 0.5 cm from the vaginal mucosa. The pathologic stage by treatment group was IA: 31%, IB: 68%, and IC: 1%. The histologic grade of the patient's tumors was grade 1: 69%, 2: 29%, and 3: 2% of patients. The median time from surgery to radiation was 34 days (range 14-66 days). The median follow-up for 286 patients with Stage IA (92 patients), IB (190 patients), and IC (4 patients) was respectively, 37, 35 and 40 months (2 patients lost to follow-up prior to 6 months). Results: Patients presented with vaginal bleeding (94%) or abnormal pap smear (6%) at a median age for Stage IA and IB, of 54 and 63 years, respectively (range 32-88). The 5-year overall actuarial survival rate was 94.5%. The 5-year actuarial survival rate by histologic grade was 97.5% and 91.5% for FIGO grade 1 and 2, respectively (p=.011). The 5-year actuarial survival rate by depth of myometrial invasion was 99.0% and 92.5% for Stage IA and IB, respectively (p=.029). Median overall time to failure is 19.5 months (range 10-36 months). The 5-year actuarial rate of local failure was 4.5%. The overall failure rate in our study group was 2.8% (8 patients), local failure only 1

  2. Delivered dose uncertainty analysis at the tumor apex for ocular brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, Hali, E-mail: hamorris@ualberta.ca; Menon, Geetha; Larocque, Matthew P.; Jans, Hans-Sonke; Sloboda, Ron S. [Department of Medical Physics, Cross Cancer Institute, Edmonton, Alberta T6G 1Z2, Canada and Department of Oncology, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada); Weis, Ezekiel [Department of Ophthalmology, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada)

    2016-08-15

    Purpose: To estimate the total dosimetric uncertainty at the tumor apex for ocular brachytherapy treatments delivered using 16 mm Collaborative Ocular Melanoma Study (COMS) and Super9 plaques loaded with {sup 125}I seeds in order to determine the size of the apex margin that would be required to ensure adequate dosimetric coverage of the tumor. Methods: The total dosimetric uncertainty was assessed for three reference tumor heights: 3, 5, and 10 mm, using the Guide to the expression of Uncertainty in Measurement/National Institute of Standards and Technology approach. Uncertainties pertaining to seed construction, source strength, plaque assembly, treatment planning calculations, tumor height measurement, plaque placement, and plaque tilt for a simple dome-shaped tumor were investigated and quantified to estimate the total dosimetric uncertainty at the tumor apex. Uncertainties in seed construction were determined using EBT3 Gafchromic film measurements around single seeds, plaque assembly uncertainties were determined using high resolution microCT scanning of loaded plaques to measure seed positions in the plaques, and all other uncertainties were determined from the previously published studies and recommended values. All dose calculations were performed using PLAQUESIMULATOR v5.7.6 ophthalmic treatment planning system with the inclusion of plaque heterogeneity corrections. Results: The total dosimetric uncertainties at 3, 5, and 10 mm tumor heights for the 16 mm COMS plaque were 17.3%, 16.1%, and 14.2%, respectively, and for the Super9 plaque were 18.2%, 14.4%, and 13.1%, respectively (all values with coverage factor k = 2). The apex margins at 3, 5, and 10 mm tumor heights required to adequately account for these uncertainties were 1.3, 1.3, and 1.4 mm, respectively, for the 16 mm COMS plaque, and 1.8, 1.4, and 1.2 mm, respectively, for the Super9 plaque. These uncertainties and associated margins are dependent on the dose gradient at the given prescription

  3. Modeling salt movement and halophytic crop growth on marginal lands with the APEX model

    Science.gov (United States)

    Goehring, N.; Saito, L.; Verburg, P.; Jeong, J.; Garrett, A.

    2016-12-01

    Saline soils negatively impact crop productivity in nearly 20% of irrigated agricultural lands worldwide. At these saline sites, cultivation of highly salt-tolerant plants, known as halophytes, may increase productivity compared to conventional salt-sensitive crops (i.e., glycophytes), thereby increasing the economic potential of marginal lands. Through a variety of mechanisms, halophytes are more effective than glycophytes at excluding, accumulating, and secreting salts from their tissues. Each mechanism can have a different impact on the salt balance in the plant-soil-water system. To date, little information is available to understand the long-term impacts of halophyte cultivation on environmental quality. This project utilizes the Agricultural Policy/Environmental Extender (APEX) model, developed by the US Department of Agriculture, to model the growth and production of two halophytic crops. The crops being modeled include quinoa (Chenopodium quinoa), which has utilities for human consumption and forage, and AC Saltlander green wheatgrass (Elymus hoffmannii), which has forage utility. APEX simulates salt movement between soil layers and accounts for the salt balance in the plant-soil-water system, including salinity in irrigation water and crop-specific salt uptake. Key crop growth parameters in APEX are derived from experimental growth data obtained under non-stressed conditions. Data from greenhouse and field experiments in which quinoa and AC Saltlander were grown under various soil salinity and irrigation salinity treatments are being used to parameterize, calibrate, and test the model. This presentation will discuss progress on crop parameterization and completed model runs under different salt-affected soil and irrigation conditions.

  4. Calibration of the APEX Model to Simulate Management Practice Effects on Runoff, Sediment, and Phosphorus Loss.

    Science.gov (United States)

    Bhandari, Ammar B; Nelson, Nathan O; Sweeney, Daniel W; Baffaut, Claire; Lory, John A; Senaviratne, Anomaa; Pierzynski, Gary M; Janssen, Keith A; Barnes, Philip L

    2017-11-01

    Process-based computer models have been proposed as a tool to generate data for Phosphorus (P) Index assessment and development. Although models are commonly used to simulate P loss from agriculture using managements that are different from the calibration data, this use of models has not been fully tested. The objective of this study is to determine if the Agricultural Policy Environmental eXtender (APEX) model can accurately simulate runoff, sediment, total P, and dissolved P loss from 0.4 to 1.5 ha of agricultural fields with managements that are different from the calibration data. The APEX model was calibrated with field-scale data from eight different managements at two locations (management-specific models). The calibrated models were then validated, either with the same management used for calibration or with different managements. Location models were also developed by calibrating APEX with data from all managements. The management-specific models resulted in satisfactory performance when used to simulate runoff, total P, and dissolved P within their respective systems, with > 0.50, Nash-Sutcliffe efficiency > 0.30, and percent bias within ±35% for runoff and ±70% for total and dissolved P. When applied outside the calibration management, the management-specific models only met the minimum performance criteria in one-third of the tests. The location models had better model performance when applied across all managements compared with management-specific models. Our results suggest that models only be applied within the managements used for calibration and that data be included from multiple management systems for calibration when using models to assess management effects on P loss or evaluate P Indices. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  5. Multisite Evaluation of APEX for Water Quality: I. Best Professional Judgment Parameterization.

    Science.gov (United States)

    Baffaut, Claire; Nelson, Nathan O; Lory, John A; Senaviratne, G M M M Anomaa; Bhandari, Ammar B; Udawatta, Ranjith P; Sweeney, Daniel W; Helmers, Matt J; Van Liew, Mike W; Mallarino, Antonio P; Wortmann, Charles S

    2017-11-01

    The Agricultural Policy Environmental eXtender (APEX) model is capable of estimating edge-of-field water, nutrient, and sediment transport and is used to assess the environmental impacts of management practices. The current practice is to fully calibrate the model for each site simulation, a task that requires resources and data not always available. The objective of this study was to compare model performance for flow, sediment, and phosphorus transport under two parameterization schemes: a best professional judgment (BPJ) parameterization based on readily available data and a fully calibrated parameterization based on site-specific soil, weather, event flow, and water quality data. The analysis was conducted using 12 datasets at four locations representing poorly drained soils and row-crop production under different tillage systems. Model performance was based on the Nash-Sutcliffe efficiency (NSE), the coefficient of determination () and the regression slope between simulated and measured annualized loads across all site years. Although the BPJ model performance for flow was acceptable (NSE = 0.7) at the annual time step, calibration improved it (NSE = 0.9). Acceptable simulation of sediment and total phosphorus transport (NSE = 0.5 and 0.9, respectively) was obtained only after full calibration at each site. Given the unacceptable performance of the BPJ approach, uncalibrated use of APEX for planning or management purposes may be misleading. Model calibration with water quality data prior to using APEX for simulating sediment and total phosphorus loss is essential. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  6. A study of return to saturation oscillations in the OSU APEX thermal hydraulic testing facility

    Science.gov (United States)

    Franz, Scott Cameron

    The purpose of this paper is to describe the flow oscillations which occur in the AP600 long term cooling test facility at Oregon State University. The AP600 system is an advanced pressurized water reactor design utilizing passive emergency cooling systems. A few hours after the initiation of a cold leg break, the passive cooling systems inject gravity fed cold water at a rate allowing steam production in the reactor vessel. Steam production in the core causes the pressure in the upper head to increase leading to flow oscillations in all the connecting reactor systems. This paper will show that the oscillations have a definite region of onset and termination for specific conditions in the APEX testing facility. Tests performed at high powers, high elevation breaks, and small break sizes do not exhibit oscillations. The APOS (Advanced Plant Oscillation Simulator) computer code has been developed using a quasi-steady state analysis for flows and a transient analysis for the core node energy balance. The pressure in the reactor head is calculated using a modified perfect gas analysis. For tank liquid inventories, a simple conservation of mass analysis is used to estimate the tank elevations. Simulation logic gleaned from APEX data and photographic evidence have been incorporated into the code to predict termination of the oscillations. Areas which would make the work more complete include a better understanding of two-phase fluid behavior for a top offtake on a pipe, more instrumentation in the core region of the APEX testing facility, and a clearer understanding of fluid conditions in the reactor barrel. Scaling of the oscillations onset and pressure amplitude are relatively straightforward, but termination and period are difficult to scale to the full AP600 plant. Differences in the core power profile and other geometrical differences between the testing facility and the actual plant make the scaling of this phenomenon to the actual plant conditions very difficult.

  7. Comparison of the accuracies of multi-frequency electronic apex locators in teeth with enlarged apical foramina: ex vivo

    Directory of Open Access Journals (Sweden)

    Mügem Aslı Ekici

    2018-01-01

    Full Text Available Objective: The aim of this study was to compare the accuracy of a newly developed multi-frequency electronic apex locator iPex II with three different multi-frequency electronic apex locators in teeth with different sizes of apical foramina. Materials and Method: Twenty-six extracted mandibular premolars were used in this study. The teeth were decoronated, and the root canals were coronally flared. Actual working length was determined by inserting a #15 K-file until the tip was visualized just within apical foramen. Actual working length was established 0.5 mm short of the distance between the rubber stopper and the file tip. Using Protaper F1, F2 and F3 files (Dentsply Maillefer, over-instrumentation 1 mm beyond the apical foramen was done. The teeth were embedded in teflon molds with alginate exposing the coronal 5 mm. Electronic working length measurements were done by using Raypex 5 (VDW, Raypex 6 (VDW, iPex (NSK Inc. and iPex II (NSK Inc. electronic apex locators. Differences between the electronic and actual working lengths were calculated. One-way analysis of variance (ANOVA was used for the statistical analysis of the accuracies of the electronic apex locators (α=0.05. Results: Inter-group comparisons revealed that there was no statistically significant difference between the accuracies of the different electronic apex locators (p>0.05. Intra-group comparisons also revealed that there was no statistically significant difference between different apical foramen sizes (p>0.05. Conclusion: iPex II and the other electronic apex locators provided similar endodontic working length measurements in teeth with enlarged apical foramina. All electronic apex locators tested in this study were found clinically acceptable for working length determination.

  8. Comparación entre los sitios de LLAMA y APEX

    Science.gov (United States)

    Bareilles, F. A.; Morras, R.; Hauscarriaga, F. P.; Guarrera, L.; Arnal, E. M.; Lepine, J. R. D.

    A comparison among the meteorological condition prevailing at the location of APEX (Atacama Pathfinder Experiment) telescope and the site selected to deploy LLAMA (Long Latin American Millimeter Array) is carried out. The later is dubbed Alto Chorrillo, and is located 4800 m above sea level and around 16 km eastward from the town of San Antonio de los Cobres (province of Salta). This work is part of a long term monitoring campaign aim at selecting sites for millimeter and submillimeter radioastronomy that is being carried out by the Instituto Argentino de Radioastronomía (IAR) since 2002. FULL TEXT IN SPANISH

  9. Endoscopic Endonasal Infrapetrous Transpterygoid Approach to the Petroclival Junction for Petrous Apex Chondrosarcoma: Technical Report.

    Science.gov (United States)

    Maurer, Adrian J; Bonney, Phillip A; Iser, Courtney R; Ali, Rohaid; Sanclement, Jose A; Sughrue, Michael E

    2015-07-01

    Chondrosarcomas of the skull base are rare tumors that present difficult management considerations due to the pathoanatomical relationships of the tumor to adjacent structures. We present the case of a 25-year-old female patient presenting with a chondrosarcoma of the right petrous apex extending inferiorly, medial to the cranial nerves. The tumor was resected via an endoscopic endonasal infrapetrous transpterygoid approach that achieved complete resection and an excellent long-term outcome with no complications. Technical nuances and potential pitfalls of the case are discussed in depth including measures to protect the carotid artery while performing the required drilling of the skull base to access the lesion.

  10. Corruption of radio metric Doppler due to solar plasma dynamics: S/X dual-frequency Doppler calibration for these effects

    Science.gov (United States)

    Winn, F. B.; Reinbold, S. R.; Yip, K. W.; Koch, R. E.; Lubeley, A.

    1975-01-01

    Doppler data from Mariner 6, 7, 9, and 10 and Pioneer 10 and 11 were discussed and the rms noise level for various sun-earth-probe angles were shown. The noise levels of both S- and X-band Doppler data for sun-earth-probe angles smaller than 20 deg were observed to be orders of magnitude greater than nominal. Such solar plasma-related Doppler degradation reduced the Mariner 10-Mercury 11 encounter navigation accuracy by nearly a factor of 10. Furthermore, this degradation was shown to be indirectly related to plasma dynamics and not a direct measure of the dynamics.

  11. The Anti-Apoptotic Properties of APEX1 in the Endothelium Require the First 20 Amino Acids and Converge on Thioredoxin-1.

    Science.gov (United States)

    Dyballa-Rukes, Nadine; Jakobs, Philipp; Eckers, Anna; Ale-Agha, Niloofar; Serbulea, Vlad; Aufenvenne, Karin; Zschauer, Tim-Christian; Rabanter, Lothar L; Jakob, Sascha; von Ameln, Florian; Eckermann, Olaf; Leitinger, Norbert; Goy, Christine; Altschmied, Joachim; Haendeler, Judith

    2017-04-20

    The APEX nuclease (multifunctional DNA repair enzyme) 1 (APEX1) has a disordered N-terminus, a redox, and a DNA repair domain. APEX1 has anti-apoptotic properties, which have been linked to both domains depending on cell type and experimental conditions. As protection against apoptosis is a hallmark of vessel integrity, we wanted to elucidate whether APEX1 acts anti-apoptotic in primary human endothelial cells and, if so, what the underlying mechanisms are. APEX1 inhibits apoptosis in endothelial cells by reducing Cathepsin D (CatD) cleavage, potentially by binding to the unprocessed form. Diminished CatD activation results in increased Thioredoxin-1 protein levels leading to reduced Caspase 3 activation. Consequently, apoptosis rates are decreased. This depends on the first twenty amino acids in APEX1, because APEX1 (21-318) induces CatD activity, decreases Thioredoxin-1 protein levels, and, thus, increases Caspase 3 activity and apoptosis. Along the same lines, APEX1 (1-20) inhibits Caspase 3 cleavage and apoptosis. Furthermore, re-expression of Thioredoxin-1 via lentiviral transduction rescues endothelial cells from APEX1 (21-318)-induced apoptosis. In an in vivo model of restenosis, which is characterized by oxidative stress, endothelial activation, and smooth muscle cell proliferation, Thioredoxin-1 protein levels are reduced in the endothelium of the carotids. APEX1 acts anti-apoptotic in endothelial cells. This anti-apoptotic effect depends on the first 20 amino acids of APEX1. As proper function of the endothelium during life span is a hallmark for individual health span, a detailed characterization of the functions of the APEX1N-terminus is required to understand all its cellular properties. Antioxid. Redox Signal. 26, 616-629.

  12. Competition between apex predators? Brown bears decrease wolf kill rate on two continents.

    Science.gov (United States)

    Tallian, Aimee; Ordiz, Andrés; Metz, Matthew C; Milleret, Cyril; Wikenros, Camilla; Smith, Douglas W; Stahler, Daniel R; Kindberg, Jonas; MacNulty, Daniel R; Wabakken, Petter; Swenson, Jon E; Sand, Håkan

    2017-02-08

    Trophic interactions are a fundamental topic in ecology, but we know little about how competition between apex predators affects predation, the mechanism driving top-down forcing in ecosystems. We used long-term datasets from Scandinavia (Europe) and Yellowstone National Park (North America) to evaluate how grey wolf ( Canis lupus ) kill rate was affected by a sympatric apex predator, the brown bear ( Ursus arctos ). We used kill interval (i.e. the number of days between consecutive ungulate kills) as a proxy of kill rate. Although brown bears can monopolize wolf kills, we found no support in either study system for the common assumption that they cause wolves to kill more often. On the contrary, our results showed the opposite effect. In Scandinavia, wolf packs sympatric with brown bears killed less often than allopatric packs during both spring (after bear den emergence) and summer. Similarly, the presence of bears at wolf-killed ungulates was associated with wolves killing less often during summer in Yellowstone. The consistency in results between the two systems suggests that brown bear presence actually reduces wolf kill rate. Our results suggest that the influence of predation on lower trophic levels may depend on the composition of predator communities. © 2017 The Authors.

  13. New electronic apex locator Romiapex A-15 presented accuracy for working length determination in permanent teeth

    Directory of Open Access Journals (Sweden)

    Etevaldo Matos Maia Filho

    2014-12-01

    Full Text Available Purpose: The present study aims to evaluate, ex vivo, the accuracy of electronic apex locators Root ZX II and Romiapex-15, for working length (WL determination in permanent teeth. Materials and Methods: Fourteen single-rooted teeth (incisors and canines, with their apices fully formed were used. The dental crowns were removed. The anatomic length of the tooth (real measurement was visually determined through the insertion of a size 10 K-file until the tip of the instrument could be observed in the apical foramen under a microscope (20X. Teeth were fixed in a model of resin and adapted into alginate soaked with saline solution, which was used as an  electrical conductor. Using a K-file, root canals were measured electronically using both devices. The results obtained for each apex locator were compared to the real measurements. The accuracy between the devices was statistically analyzed using the Bland-Altman graph, Intraclass Correlation Coefficient (ICC, and Student’s t-test. Results: The mean difference between the measurements using the Root ZX II was 0.277mm greater than the real measurement, while the measurements from the Romiapex-15 were 0.308mm higher on average. The comparison between Root ZX II and Romiapex-15 had no significant difference (p= 0.868. Conclusion: It was concluded that Root ZX II and Romiapex-15 had similar accuracy. Romiapex-15 could be an option for WL determination in permanent teeth.

  14. Oyster polynuclear aromatic hydrocarbon fingerprinting applied to the Apex barge oil spill

    International Nuclear Information System (INIS)

    Wade, T.L.; Jackson, T.J.; McDonald, T.J.; Sericano, J.L.; Brooks, J.M.

    1993-01-01

    An estimated 692,000 gallons of catalytic feed stock oil was spilled into Galveston Bay on July 28, 1990, when a tanker collided with three Apex barges in the Houston Ship Channel. Oysters were collected and analyzed from Galveston Bay Todd's Dump (GBRD) before the spill and after the spill. Oysters were also collected from Galveston Bay Redfish Island (GBRI), a site known to be impacted by the spill, 37 and 110 days after the spill. The spilled oil was also analyzed. The concentration of 18 polynuclear aromatic hydrocarbons (PAH) measured as part of the National Oceanic and Atmospheric Administration's National Status ampersand Trends (NS ampersand T) showed a sharp increase from 100 ng/g to over 600 ng/g. Concentrations of these 18 PAHs were also found at GBRI. Fingerprinting techniques applied to data from oyster analyses demonstrated the presence of bioavailable Apex Barge oil 37, 110, and 132 days after the spill at GHTD and GBRI. Fingerprinting becomes less diagnostic with time due to possible environmental weathering of the oil. The fingerprint from GBTD 495 and 851 days after the spill will be presented and discussed

  15. Investigating of the Field Emission Performance on Nano-Apex Carbon Fiber and Tungsten Tips

    Science.gov (United States)

    Mousa, Marwan S.; Alnawasreh, Shadi; Madanat, Mazen A.; Al-Rabadi, Anas N.

    2015-10-01

    Field electron emission measurements have been performed on carbon-based and tungsten microemitters. Several samples of both types of emitters with different apex radii have been obtained employing electrolytic etching techniques using sodium hydroxide (NaOH) solution with different molarities depending on the material used. A suitable, home-built, field electron microscope (FEM) with 10 mm tip to screen separation distance was used to electrically characterize the electron emitters. Measurements were carried out under ultra high vacuum (UHV) conditions with base pressure of 10-9 mbar. The current-voltage characteristics (I-V) presented as Fowler-Nordheim (FN) type plots, and field electron emission images have been recorded. In this work, initial comparison of the field electron emission performance of these micro and nanoemitters has been carried out, with the aim of obtaining a reliable, stable and long life powerful electron source. We compare the apex radii measured from the micrographs obtained from the SEM images to those extracted from the FN-type _I-V_plots for carbon fibers and tungsten tips.

  16. Investigating of the Field Emission Performance on Nano-Apex Carbon Fiber and Tungsten Tips

    International Nuclear Information System (INIS)

    Mousa, Marwan S; Alnawasreh, Shadi; Al-Rabadi, Anas N; Madanat, Mazen A

    2015-01-01

    Field electron emission measurements have been performed on carbon-based and tungsten microemitters. Several samples of both types of emitters with different apex radii have been obtained employing electrolytic etching techniques using sodium hydroxide (NaOH) solution with different molarities depending on the material used. A suitable, home-built, field electron microscope (FEM) with 10 mm tip to screen separation distance was used to electrically characterize the electron emitters. Measurements were carried out under ultra high vacuum (UHV) conditions with base pressure of 10 -9 mbar. The current-voltage characteristics (I-V) presented as Fowler-Nordheim (FN) type plots, and field electron emission images have been recorded. In this work, initial comparison of the field electron emission performance of these micro and nanoemitters has been carried out, with the aim of obtaining a reliable, stable and long life powerful electron source. We compare the apex radii measured from the micrographs obtained from the SEM images to those extracted from the FN-type -I-V-plots for carbon fibers and tungsten tips. (paper)

  17. In vitro comparison of working length determination using three different electronic apex locators

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    Alper Kuştarci

    2014-01-01

    Full Text Available Background: The aim of this study was to compare the accuracy of the apex-locating functions of DentaPort ZX, Raypex 5 and Endo Master electronic apex locators (EALs in vitro. Materials and Methods: Thirty extracted human single-rooted teeth with mature apices were used for the study. The real working length (RWL was established by subtracting 0.5 mm from the actual root canal length. All teeth were mounted in an alginate model that was especially developed to test the EALs and the teeth were then measured with each EAL. The results were compared with the corresponding RWL, which was subtracted from the electronically determined distance. Data were analyzed using a paired-samples t-test, a Chi-square test and a repeated measure analysis of variance evaluation at the 0.05 level of significance. Results: Statistical analysis showed that no significant difference was found among all EALs (P > 0.05. Conclusion: The accuracy of the EALs was evaluated and all of the devices showed an acceptable determination of electronic working length between the ranges of ±0.5 mm.

  18. Stem Migration and Fretting Corrosion of the Antirotation Pin in the K2/Apex Hip System.

    Science.gov (United States)

    Kent, Michael; Edmondson, Mark; Ebert, Jay; Nivbrant, Nils; Kop, Alan; Wood, David; De Steiger, Richard

    2016-03-01

    Many exchangeable neck hip systems have been withdrawn because of fretting corrosion at the neck/stem coupling. Our prospective randomized study evaluating stem stability (Roentgen stereophotogrammetric analysis, dual-energy x-ray absorptiometry) and clinical outcomes between the K2/Apex hip systems was ceased early because of a withdrawal of the stems which had an unfavorably high early revision rate reported in the Australian Orthopaedic Association National Joint Registry (9.3% at 3 years). At 2 years, there are no clinical differences between the stems. Roentgen stereophotogrammetric analysis has identified a high proportion of potentially concerning subsidence and retroversion in both groups, more marked in the K2 stem, although mostly in asymptomatic patients. Dual-energy x-ray absorptiometry has shown similar bone density around the stems. Retrieval analysis of 3 study patients showed fretting corrosion of the antirotation pin and aseptic lymphocyte-dominated vasculitis-associated lesion, with no relationship to bearing type or size. Analysis of 7 further nonstudy K2/Apex stems confirmed similar corrosion. This study shows potentially concerning subsidence of both stems and is the first to describe corrosion at the neck-stem interface and a relationship to metal-related pathology. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  19. Orbital apex cyst: a rare cause of compressive optic neuropathy post-functional endoscopic sinus surgery

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    Koh YN

    2017-07-01

    Full Text Available Yi Ni Koh,1,2 Shu Fen Ho,2 Letchumanan Pathma,3 Harvinder Singh,3 Embong Zunaina1 1Department of Ophthalmology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia; 2Department of Ophthalmology, 3Department of Otorhinolaryngology, Hospital Raja Permaisuri Bainun, Ipoh, Perak, Malaysia Abstract: There are various causes that can lead to compressive optic neuropathy. We present here orbital apex cyst as an unusual cause of compressive optic neuropathy in a 49-year-old male. He presented with 2 weeks painless loss of vision in the left eye with left-sided headache. He had had left functional endoscopic sinus surgery for left nasal polyps 4 years earlier. Magnetic resonance imaging of brain and orbit revealed a left discrete orbital nodule, possibly orbital cyst or mucocele, which was compressing on the left optic nerve. Left eye vision improved markedly from hand movement to 6/36 pinhole 6/18 after initiation of intravenous dexamethasone. A subsequent endoscopic endonasal left optic nerve decompression found the orbital nodule lesion to be an orbital cyst. Marsupialization was performed instead of excision, as the cyst ruptured intraoperatively. Postoperative vision improved to 6/7.5 with normal optic nerve function postoperatively. Possible cause of orbital apex cyst is discussed. Keywords: orbital cyst, compressive optic neuropathy, functional endoscopic sinus surgery

  20. Detailed Surgical Anatomy of Prostate: Relationship between Urethra and Dorsal Vein Complex with Apex.

    Science.gov (United States)

    Tunc, Lutfi; Akin, Yigit; Gumustas, Huseyin; Ak, Esat; Peker, Tuncay; Veneziano, Domenico; Guneri, Cagri

    2016-01-01

    To describe our surgical technique for dissecting the apex of prostate during robotic-assisted laparoscopic radical prostatectomy (RALP) and detailed surgical anatomy of prostate including relationship between urethra and dorsal vein complex with apex. In retrospective view of prospective collected data, 73 patients underwent RALP between December 2012 and September 2014. Surgical anatomy of prostate was revealed in all procedures. Quality of life (QoL) scores were assessed before, immediately after catheter removal, and 1 month after surgery. We divided urinary continence into 3 groups, as very early continence; continence at time of urethral catheter removal, early continent; and continence 1 month after surgery. The rest of the patients were accepted as continence. The mean follow-up was 10.2 ± 5.4 months and mean age was 61.5 ± 6.6. Maximum protection of urethra could be provided in all. Mean catheter removal was 8.9 ± 1.7 days, and all patients were continent at the time of catheter removal. QoL scores before RALP could be protected after surgery (p = 0.2). Neither conversion to open/conventional laparoscopic surgery nor complications related with bladder neck were detected. Our surgical technique can be a strong candidate for being a surgical technique for preserving urethra and very early continence could be provided after surgery. © 2016 S. Karger AG, Basel.

  1. Long-term observations of Boreal Toads at an ARMI apex site

    Science.gov (United States)

    Corn, Paul Stephen; Muths, Erin L.; Pilliod, David S.

    2011-01-01

    The U.S. Geological Survey’s Amphibian Research and Monitoring Initiative (ARMI) is a national project with goals to monitor the status and trends of amphibians, conduct research on causes of declines, and provide information and support to management agencies for conservation of amphibian populations. ARMI activities are organized around extensive inventories and place-based monitoring (such as collaboration with the Greater Yellowstone Inventory and Monitoring Network), and intensive population studies and research at selected locations (apex sites). One such site is an oxbow pond on the Buffalo Fork near the Black Rock Ranger Station east of Grand Teton National Park. We have been conducting mark-recapture of boreal toads (Anaxyrus boreas) at Black Rock since 2002. In concert with studies of other toad populations in the Rocky Mountains, we have documented a high rate of incidence of the chytrid fungus Batrachochytrium dendrobatidis (Bd) and a negative rate of growth of the toad population, but not the population crash or extinction observed in other populations with high prevalence of Bd. Long-term observations at other ARMI apex sites have proven invaluable for studying effects of climate change on amphibian behavior, and the Black Rock site has been upgraded with onsite recording of weather data and auditory monitoring of other amphibian species. Continued research at Black Rock will be critical for understanding the interrelated effects of climate and disease on amphibians in the Greater Yellowstone Ecosystem.

  2. Orbital apex syndrome associated with fractures of the inferomedial orbital wall

    Directory of Open Access Journals (Sweden)

    Sugamata A

    2013-03-01

    Full Text Available Akira SugamataDepartment of Plastic and Reconstructive Surgery, Tokyo Medical University Hachioji Medical Center, Tokyo, JapanAbstract: Although trauma is one of the main causes of orbital apex syndrome (OAS, reports of OAS associated with orbital fractures are relatively rare. We recently treated two patients who sustained severe visual impairment with damage to multiple cranial nerves (third to sixth associated with inferomedial orbital wall fractures. In these patients, posterior movement of the globe caused neuropathy of the cranial and optic nerves by posterior globe edema and hemorrhage, or direct impact between the globe and wall, which might then have induced OAS in the cases described in this report. Steroid therapy was unsuccessful for optic neuropathy due to the delay between injury and administration. When treating patients with inferomedial orbital blowout fractures due to globe-to-wall contact, it is necessary to routinely assess and monitor visual acuity since there may be a delay between the injury and OAS onset.Keywords: orbital apex syndrome, orbital fracture, blowout fracture, optic nerve, globe-to-wall contact mechanism

  3. Medullary Venous Hypertension Secondary to a Petrous Apex Dural Arteriovenous Fistula: A Case Report

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    Meghan Murphy

    2012-11-01

    Full Text Available Background: Dural arteriovenous fistulae (dAVF are common intracranial vascular lesions typically becoming symptomatic with cortical venous hypertension and possible hemorrhage. Here, we present a case illustration of a petrous apex dAVF with marked medullary venous hypertension and a unique clinical presentation. Methods: Case report. Results: A 72-year-old female, whose clinical progression was significant for altered mental status and progressive weakness, presented with diplopia, right leg paresis, and ataxia. Magnetic resonance imaging revealed edema involving the medulla. On digital subtraction cerebral angiogram, the patient was found to have a petrous apex dAVF, Cognard type IV. Following treatment with Onyx embolization, her symptoms rapidly improved, with complete resolution of diplopia and drastic improvement of her ataxia. Conclusion: The importance of this case is in the presentation and deterioration of the clinical exam, resembling an acute ischemic event. Further, this case illustrates that dAVF may cause venous hypertension with rapid onset of focal neurologic symptoms not exclusive to cortical locations.

  4. Postoperative high dose rate vaginal apex brachytherapy in stage I endometrial adenocarcinoma

    International Nuclear Information System (INIS)

    Turner, B.; Knisely, J.; Kacinski, B.; Roberts, K.; Peschel, R.; Gumbs, A.; Rutherford, T.; Edraki, B.; Schwartz, P.; Chambers, J.; Kohorn, E.; Wilson, L.

    1996-01-01

    Introduction: Patients with stage I endometrial adenocarcinoma have traditionally been treated with TAH/BSO and radiation. The reported incidence of local recurrence in surgically treated patients with Figo stage IA or IB endometrial adenocarcinoma is 4-10% at 2 years. Combined surgery and radiation has resulted in a reduction of recurrence to 2-6%. We report the presentation, local and distant control, salvage rate, survival and complications for patients undergoing high dose rate (HDR) vaginal apex brachytherapy following surgery. Methods: Between 1985 and 1994 a total of 302 patients with Figo stage I endometrial carcinoma were treated with HDR Ir-192 vaginal apex brachytherapy to a total dose of 21 Gy in 3 fractions at 0.5 cm from the vaginal mucosa. The pathologic stage by treatment group was IA: 31%, IB: 68%, and IC: 1%. The histologic grade of the patient's tumors was grade 1: 69%, 2: 27%, and 3: 4%. The median time from surgery to radiation was 33 days (range 14-66 days). The median follow-up for 300 patients with stage IA (91 patients), IB (205 patients), and IC (4 patients) was respectively 36, 34 and 40 months (2 patients lost to follow-up prior to 6 months). Results: Patients presented with vaginal bleeding (94%) or abnormal pap smear (6%) at a median age for stage IA and IB, of 55 and 64 years, respectively. The crude overall survival of the patient population at 2 years is 95%. Median overall time to failure is 19.5 months (range 10-36 months). The overall failure rate was 2.7% (8 patients), local failure only 1.0% (38% of failed group), distant failure only 0.3% (12% of failed group) and combined local/distant failure 1.3% (50% of failed group). The local failure rate for pathologic stage IA patients was 1.0% and no distant disease was observed. The local failure rate for pathologic stage IB patients was 3.4% 7/205 and distant failure was 2.4% 5/205. The majority of patients with recurrence had grade 2 histologic changes 5/8. The overall salvage rate

  5. Teat apex colonization with coagulase-negative Staphylococcus species before parturition: Distribution and species-specific risk factors.

    Science.gov (United States)

    De Visscher, A; Piepers, S; Haesebrouck, F; De Vliegher, S

    2016-02-01

    Coagulase-negative staphylococci (CNS) are the main cause of bovine intramammary infections and are also abundantly present in extramammary habitats such as teat apices. Teat apex colonization (TAC) with CNS has already been explored in lactating dairy cows at the species level, whereas this is not true for dry cows and end-term heifers. Therefore, the aim of this observational study was to describe CNS TAC in nonlactating dairy cows and end-term heifers in Flemish dairy herds and to identify associated risk factors at the herd, cow, and quarter level. All CNS were molecularly identified to the species level using transfer RNA intergenic spacer PCR (tDNA-PCR) and sequencing of the 16S rRNA gene, allowing for species-specific statistical analyses using multivariable, multilevel logistic regression. Staphylococcus devriesei, Staphylococcus chromogenes, Staphylococcus haemolyticus, and Staphylococcus equorum were the most frequently isolated species. Staphylococcus chromogenes was the sole species colonizing teat apices of cows and heifers in all herds, whereas large between-herd differences were observed for the other species. Teat apices of red and white Holstein Friesians, of quarters dried off without an internal teat sealer, and swabbed in months with lower precipitation and higher ambient temperature were significantly more likely to be colonized by S. devriesei. Slightly dirty teat apices and teat apices swabbed in months with lower precipitation had higher odds of being colonized by S. chromogenes, whereas teat apices sampled in months with lower precipitation and higher ambient temperature were more likely to be colonized by S. haemolyticus. Dirty teat apices and teat apices swabbed in months with lower ambient temperature in combination with low precipitation had higher odds of being colonized by S. equorum. Diverse factors explaining CNS TAC, yet mostly related to humidity, ambient temperature, and hygiene, substantiate differences in epidemiological

  6. Healing of apical rarefaction of three nonvital open apex anterior teeth using a white portland cement apical plug

    Directory of Open Access Journals (Sweden)

    Amitabha Chakraborty

    2012-01-01

    Full Text Available The major challenge of performing root canal treatment in an open apex pulp-less tooth is to obtain a good apical seal. MTA has been successfully used to achieve a good apical seal, wherein the root canal obturation can be done immediately. MTA and White Portland Cement has been shown similarity in their physical, chemical and biological properties and has also shown similar outcome when used in animal studies and human trials. In our study, open apex of three non vital upper central incisors has been plugged using modified white Portland cement. 3 to 6 months follow up revealed absence of clinical symptoms and disappearance of peri-apical rarefactions. The positive clinical outcome may encourage the future use of white Portland cement as an apical plug material in case of non vital open apex tooth as much cheaper substitute of MTA.

  7. Determining the apical terminus of root-end resected teeth using three modern apex locators: a comparative ex vivo study.

    Science.gov (United States)

    ElAyouti, A; Kimionis, I; Chu, A-L; Löst, C

    2005-11-01

    To assess ex vivo the accuracy of various electronic apex locators in locating the apical terminus of root-end resected teeth. Ninety extracted human posterior teeth (182 root canals) were prepared to a minimum size of 40 and filled with gutta-percha and sealer. After resection of the apical 3 mm of the root, the root canal filling was removed using HERO rotary instruments. The size of the root canal at the apical terminus after removal of the filling ranged from size 50 to 90. The root canal length to the apical terminus was determined using 3 apex locators (Root ZX, Raypex4 and Apex Pointer). A new mounting model that utilized a micrometer was used to perform the measurements and to visually determine the actual position of the apical terminus. The frequency of locating the apical terminus and the corresponding 95% confidence interval (CI) were calculated. Additionally, the coefficient of repeatability of each apex locator and the limits of inter-operator agreement were determined. All apex locators showed an acceptable repeatability (0.02-0.03 mm coefficient of repeatability) and narrow limits of inter-operator agreement (+0.07 and -0.07 mm). The accuracy of determining the apical terminus within 1 mm in the root canal was as follows: Root ZX 90% (164/182 root-canals) [95%CI: 86-94%], Raypex4 74% (135/182 root-canals) [95%CI: 68-80%], and Apex Pointer 71% (129/182 root canals) [95%CI: 65-77%]. No over-instrumentation resulted when the Root ZX device was used. In contrast, using the Raypex4 or the Apex Pointer device resulted in over-instrumentation in 8 of 182 root canals (4%). Under the conditions of this study all three apex locators were able to detect the apical terminus of root-end resected teeth with an acceptable range. The Root ZX device was the most accurate without over-instrumentation of the root canals.

  8. Effect of gamma irradiation on seed germination and organization of shoot apex in Solanum melongena and Capsicum annum

    International Nuclear Information System (INIS)

    Patel, J.D.; Shah, J.J.

    1974-01-01

    Seeds of S. melongena and C. annum were irradiated with 10, 20 and 30 kR exposures of gamma rays. All doses bring about morphological and structural changes in the shoot apex. Cytohistological zonation is absent in the shoot apex of treated seeds. Tunica and corpus cells become inactive. The plastochron period between the two successive leaf primordia is shorter in irradiated shoot apices than in unirradiated ones. In Capsicum certain shoot apices showed arrested internodes between the cotyledon and next leaf. (author)

  9. APEX Snaps First Close-up of Star Factories in Distant Universe

    Science.gov (United States)

    2010-03-01

    For the first time, astronomers have made direct measurements of the size and brightness of regions of star-birth in a very distant galaxy, thanks to a chance discovery with the APEX telescope. The galaxy is so distant, and its light has taken so long to reach us, that we see it as it was 10 billion years ago. A cosmic "gravitational lens" is magnifying the galaxy, giving us a close-up view that would otherwise be impossible. This lucky break reveals a hectic and vigorous star-forming life for galaxies in the early Universe, with stellar nurseries forming one hundred times faster than in more recent galaxies. The research is published online today in the journal Nature. Astronomers were observing a massive galaxy cluster [1] with the Atacama Pathfinder Experiment (APEX) telescope, using submillimetre wavelengths of light, when they found a new and uniquely bright galaxy, more distant than the cluster and the brightest very distant galaxy ever seen at submillimetre wavelengths. It is so bright because the cosmic dust grains in the galaxy are glowing after being heated by starlight. The new galaxy has been given the name SMM J2135-0102. "We were stunned to find a surprisingly bright object that wasn't at the expected position. We soon realised it was a previously unknown and more distant galaxy being magnified by the closer galaxy cluster," says Carlos De Breuck from ESO, a member of the team. De Breuck was making the observations at the APEX telescope on the plateau of Chajnantor at an altitude of 5000 m in the Chilean Andes. The new galaxy SMM J2135-0102 is so bright because of the massive galaxy cluster that lies in the foreground. The vast mass of this cluster bends the light of the more distant galaxy, acting as a gravitational lens [2]. As with a telescope, it magnifies and brightens our view of the distant galaxy. Thanks to a fortuitous alignment between the cluster and the distant galaxy, the latter is strongly magnified by a factor of 32. "The magnification

  10. Mass and energy supply of a cool coronal loop near its apex

    Science.gov (United States)

    Yan, Limei; Peter, Hardi; He, Jiansen; Xia, Lidong; Wang, Linghua

    2018-03-01

    Context. Different models for the heating of solar corona assume or predict different locations of the energy input: concentrated at the footpoints, at the apex, or uniformly distributed. The brightening of a loop could be due to the increase in electron density ne, the temperature T, or a mixture of both. Aim. We investigate possible reasons for the brightening of a cool loop at transition region temperatures through imaging and spectral observation. Methods: We observed a loop with the Interface Region Imaging Spectrograph (IRIS) and used the slit-jaw images together with spectra taken at a fixed slit position to study the evolution of plasma properties in and below the loop. We used spectra of Si IV, which forms at around 80 000 K in equilibrium, to identify plasma motions and derive electron densities from the ratio of inter-combination lines of O IV. Additional observations from the Solar Dynamics Observatory (SDO) were employed to study the response at coronal temperatures (Atmospheric Imaging Assembly, AIA) and to investigate the surface magnetic field below the loop (Helioseismic and Magnetic Imager, HMI). Results: The loop first appears at transition region temperatures and later also at coronal temperatures, indicating a heating of the plasma in the loop. The appearance of hot plasma in the loop coincides with a possible accelerating upflow seen in Si IV, with the Doppler velocity shifting continuously from -70 km s-1 to -265 km s-1. The 3D magnetic field lines extrapolated from the HMI magnetogram indicate possible magnetic reconnection between small-scale magnetic flux tubes below or near the loop apex. At the same time, an additional intensity enhancement near the loop apex is visible in the IRIS slit-jaw images at 1400 Å. These observations suggest that the loop is probably heated by the interaction between the loop and the upflows, which are accelerated by the magnetic reconnection between small-scale magnetic flux tubes at lower altitudes. Before

  11. Dynamic variable selection in SNP genotype autocalling from APEX microarray data

    Directory of Open Access Journals (Sweden)

    Zamar Ruben H

    2006-11-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs are DNA sequence variations, occurring when a single nucleotide – adenine (A, thymine (T, cytosine (C or guanine (G – is altered. Arguably, SNPs account for more than 90% of human genetic variation. Our laboratory has developed a highly redundant SNP genotyping assay consisting of multiple probes with signals from multiple channels for a single SNP, based on arrayed primer extension (APEX. This mini-sequencing method is a powerful combination of a highly parallel microarray with distinctive Sanger-based dideoxy terminator sequencing chemistry. Using this microarray platform, our current genotype calling system (known as SNP Chart is capable of calling single SNP genotypes by manual inspection of the APEX data, which is time-consuming and exposed to user subjectivity bias. Results Using a set of 32 Coriell DNA samples plus three negative PCR controls as a training data set, we have developed a fully-automated genotyping algorithm based on simple linear discriminant analysis (LDA using dynamic variable selection. The algorithm combines separate analyses based on the multiple probe sets to give a final posterior probability for each candidate genotype. We have tested our algorithm on a completely independent data set of 270 DNA samples, with validated genotypes, from patients admitted to the intensive care unit (ICU of St. Paul's Hospital (plus one negative PCR control sample. Our method achieves a concordance rate of 98.9% with a 99.6% call rate for a set of 96 SNPs. By adjusting the threshold value for the final posterior probability of the called genotype, the call rate reduces to 94.9% with a higher concordance rate of 99.6%. We also reversed the two independent data sets in their training and testing roles, achieving a concordance rate up to 99.8%. Conclusion The strength of this APEX chemistry-based platform is its unique redundancy having multiple probes for a single SNP. Our

  12. Apex-to-Cupola Distance Following VATS Predicts Recurrence in Patients With Primary Spontaneous Pneumothorax

    Science.gov (United States)

    Chang, Jia-Ming; Lai, Wu-Wei; Yen, Yi-Ting; Tseng, Yau-Lin; Chen, Ying-Yuan; Wu, Ming-Ho; Chen, Wei; Light, Richard W.

    2015-01-01

    Abstract Our study sought to determine whether the size of the residual apical pleural space in young patients with primary spontaneous pneumothorax (PSP) following video-assisted thoracoscopic surgery is associated with the risk of recurrence. We retrospectively reviewed patients (≤30 years’ old) with primary spontaneous pneumothorax following thoracoscopic surgery (2002–2010) in a university-affiliated hospital. The size of residual apical pleural space was estimated by measuring the apex-to-cupola distance on a postoperative chest radiograph at 2 time windows: first between postoperative day (POD) 0 and 3, and second between POD 4 and 14. A total of 149 patients were enrolled with a median follow-up of 11.2 months (interquartile range, 0.95–29.5 months), of whom 141 (94.6%) were male with a mean age of 20 years. The postoperative recurrence rate was 11.4%. Comparing the characteristics between the patients with and without recurrent pneumothorax, the patients with recurrence were younger (18.2 + 2.4 vs 20.7 + 3.7 years, P = 0.008), with a lower rate of pleurodesis (35% vs1 69%, P = 0.037), longer apex-to-cupola distance at POD 0 to 3 (22.41 ± 19.56 vs 10.07 ± 10.83 mm, P pneumothorax, age 10 mm (P = 0.027, OR: 5.319), and no pleurodesis during VATS (P = 0.022, OR: 5.042) were independent risk factors for recurrent pneumothorax. The recurrence rate was not low (11.4%) in young patients with PSP following VATS. Residual apical pleural space with apex-to-cupola distance of 10 mm or greater at POD 0 to 3, younger age, and no pleurodesis would increase postoperative recurrence of primary spontaneous pneumothorax. PMID:26376396

  13. Bioremediation efficacy in Marrow Marsh following the Apex oil spill, Galveston Bay, Texas

    International Nuclear Information System (INIS)

    Nadeau, R.; Singhvi, R.; Ryabik, J.; Lin, Yihua; Syslo, J.

    1992-01-01

    Samples taken from Marrow Marsh in Galveston Bay, Texas were taken to assess the efficacy of the August 5, 1990 bioremediation treatment in the marsh following the Apex barges oil spill on July 28, 1990. The bioremediation treatment combined a lyophilized bacterial mixture and a nutrient mix containing phosphorus and nitrogen. Samples from the marsh had been collected over a 96 h period from both treated and untreated oiled sites. Oil fingerprinting, fatty acid analysis, polynuclear aromatic hydrocarbons analysis, and total petroleum hydrocarbons analysis were performed to evaluate changes in the chemical characteristics of spilled oil. Results of analyses, although not statistically reliable, failed to support the occurrence of any definite chemical alteration in the spilled oil that could be attributed to the bioremediation treatment. The relatively short sampling period and the number of samples taken, however, may have been insufficient to document the efficacy of the overall bioremediation effect. 13 refs., 6 figs., 4 tabs

  14. Interdisciplinary Approach to a Tooth with Open Apex and Persistent Sinus

    Directory of Open Access Journals (Sweden)

    Anoop N. Das

    2015-01-01

    Full Text Available Traumatic injuries in childhood may disrupt root development leading to a tooth with open apex. Apexification procedures in such cases aim at root end closure after reasonable period of time. In some chronic cases, complete healing of the periapical area does not occur resulting in development of a nonhealing sinus. Failure of nonsurgical approach in such cases needs surgical intervention permitting thorough periapical curettage. In the present case, apexification procedure with MTA achieved root end closure but failed to heal the sinus for which surgical treatment was completed with thorough periapical curettage and application of platelet rich fibrin (PRF and a combination of β-tricalcium phosphate and hydroxyapatite resulted in healing.

  15. Transition zone cells reach G2 phase before initiating elongation in maize root apex

    Directory of Open Access Journals (Sweden)

    M. Victoria Alarcón

    2017-06-01

    Full Text Available Root elongation requires cell divisions in the meristematic zone and cell elongation in the elongation zone. The boundary between dividing and elongating cells is called the transition zone. In the meristem zone, initial cells are continuously dividing, but on the basal side of the meristem cells exit the meristem through the transition zone and enter in the elongation zone, where they stop division and rapidly elongate. Throughout this journey cells are accompanied by changes in cell cycle progression. Flow cytometry analysis showed that meristematic cells are in cycle, but exit when they enter the elongation zone. In addition, the percentage of cells in G2 phase (4C strongly increased from the meristem to the elongation zone. However, we did not observe remarkable changes in the percentage of cells in cell cycle phases along the entire elongation zone. These results suggest that meristematic cells in maize root apex stop the cell cycle in G2 phase after leaving the meristem.

  16. Novel apexification method in a non-vital tooth with an open apex: a case report.

    Directory of Open Access Journals (Sweden)

    Hamid Razavian

    2014-06-01

    Full Text Available Many materials have been introduced for apexification each having their own advantages and disadvantages. This case report aims to present a new method of apexification using a combination of deproteinized bovine bone mineral (DBBM and enamel matrix derivative (EMD. After irrigating the canal of the maxillary right canine with 2.5 % sodium hypochlorite, a mixture of Bio-Oss and EMD was packed into the apical region for formation of an apical barrier and the canal was obturated by thermoplastic gutta percha technique with AH26 sealer; coronal seal was achieved by resin bonded composite. The size of the periapical lesion decreased significantly after 3, 6, 12 and 18-months. The patient had no radiographic signs or clinical symptoms at 24-month follow up and complete maturation of the apex and healing of the periapical bone were achieved.

  17. Persistent scarring and dilated cardiomyopathy suggest incomplete regeneration of the apex resected neonatal mouse myocardium

    DEFF Research Database (Denmark)

    Andersen, Ditte Caroline; Jensen, Charlotte Harken; Baun, Christina

    2016-01-01

    Heart damage in mammals is generally considered to result in scar formation, whereas zebrafish completely regenerate their hearts following an intermediate and reversible state of fibrosis after apex resection (AR). Recently, using the AR procedure, one-day-old mice were suggested to have full...... capacity for cardiac regeneration as well. In contrast, using the same mouse model others have shown that the regeneration process is incomplete and that scarring still remains 21days after AR. The present study tested the hypothesis that like in zebrafish, fibrosis in neonatal mammals could...... be an intermediate response before the onset of complete heart regeneration. Myocardial damage was performed by AR in postnatal day 1 C57BL/6 mice, and myocardial function and scarring assessed at day 180 using F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) and histology, respectively. AR mice...

  18. Cost Analysis of Operation Theatre Services at an Apex Tertiary Care Trauma Centre of India.

    Science.gov (United States)

    Siddharth, Vijaydeep; Kumar, Subodh; Vij, Aarti; Gupta, Shakti Kumar

    2015-12-01

    Operating room services are one of the major cost and revenue-generating centres of a hospital. The cost associated with the provisioning of operating department services depends on the resources consumed and the unit costs of those resources. The objective of this study was to calculate the cost of operation theatre services at Jai Prakash Narayan Apex Trauma Centre, AIIMS, New Delhi. The study was carried out at the operation theatre department of Jai Prakash Narayan Apex Trauma Centre (JPNATC), AIIMS from April 2010 to March 2011 after obtaining approval from concerned authorities. This study was observational and descriptive in nature. Traditional (average or gross) costing methodology was used to arrive at the cost for the provisioning of operation theatre (OT) services. Cost was calculated under two heads; as capital and operating cost. Annualised cost of capital assets was calculated according to the methodology prescribed by the World Health Organization and operating costs were taken on actual basis; thereafter, per day cost of OT services was obtained. The average number of surgeries performed in the trauma centre per day is 13. The annual cost of providing operating room services at JPNATC, New Delhi was calculated to be 197,298,704 Indian rupees (INR) (US$ 3,653,679), while the per hour cost was calculated to be INR 22,626.92 (US$ 419). Majority of the expenditures were for human resource (33.63 %) followed by OT capital cost (31.90 %), consumables (29.97 %), engineering maintenance cost (2.55 %), support services operating cost (1.22 %) and support services capital cost (0.73 %). Of the total cost towards the provisioning of OT services, 32.63 % was capital cost while 67.37 % is operating cost. The results of this costing study will help in the future planning of resource allocation within the financial constraints (US$ 1 = INR 54).

  19. Modified APEX model for Simulating Macropore Phosphorus Contributions to Tile Drains.

    Science.gov (United States)

    Ford, William I; King, Kevin W; Williams, Mark R; Confesor, Remegio B

    2017-11-01

    The contribution of macropore flow to phosphorus (P) loadings in tile-drained agricultural landscapes remains poorly understood at the field scale, despite the recognized deleterious impacts of contaminant transport via macropore pathways. A new subroutine that couples existing matrix-excess and matrix-desiccation macropore flow theory and a modified P routine is implemented in the Agricultural Policy Environmental eXtender (APEX) model. The original and modified formulation were applied and evaluated for a case study in a poorly drained field in Western Ohio with 31 months of surface and subsurface monitoring data. Results highlighted that a macropore subroutine in APEX improved edge-of-field discharge calibration and validation for both tile and total discharge from satisfactory and good, respectively, to very good and improved dissolved reactive P load calibration and validation statistics for tile P loads from unsatisfactory to very good. Output from the calibrated macropore simulations suggested median annual matrix-desiccation macropore flow contributions of 48% and P load contributions of 43%, with the majority of loading occurring in winter and spring. While somewhat counterintuitive, the prominence of matrix-desiccation macropore flow during seasons with less cracking reflects the importance of coupled development of macropore pathways and adequate supply of the macropore flow source. The innovative features of the model allow for assessments of annual macropore P contributions to tile drainage and has the potential to inform P site assessment tools. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  20. Southern Phosphorus Indices, Water Quality Data, and Modeling (APEX, APLE, and TBET) Results: A Comparison.

    Science.gov (United States)

    Osmond, Deanna; Bolster, Carl; Sharpley, Andrew; Cabrera, Miguel; Feagley, Sam; Forsberg, Adam; Mitchell, Charles; Mylavarapu, Rao; Oldham, J Larry; Radcliffe, David E; Ramirez-Avila, John J; Storm, Dan E; Walker, Forbes; Zhang, Hailin

    2017-11-01

    Phosphorus (P) Indices in the southern United States frequently produce different recommendations for similar conditions. We compared risk ratings from 12 southern states (Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, and Texas) using data collected from benchmark sites in the South (Arkansas, Georgia, Mississippi, North Carolina, Oklahoma, and Texas). Phosphorus Index ratings were developed using both measured erosion losses from each benchmark site and Revised Universal Soil Loss Equation 2 predictions; mostly, there was no difference in P Index outcome. The derived loss ratings were then compared with measured P loads at the benchmark sites by using equivalent USDA-NRCS P Index ratings and three water quality models (Annual P Loss Estimator [APLE], Agricultural Policy Environmental eXtender [APEX], and Texas Best Management Practice Evaluation Tool [TBET]). Phosphorus indices were finally compared against each other using USDA-NRCS loss ratings model estimate correspondence with USDA-NRCS loss ratings. Correspondence was 61% for APEX, 48% for APLE, and 52% for TBET, with overall P index correspondence at 55%. Additive P Indices (Alabama and Texas) had the lowest USDA-NRCS loss rating correspondence (31%), while the multiplicative (Arkansas, Florida, Louisiana, Mississippi, South Carolina, and Tennessee) and component (Georgia, Kentucky, and North Carolina) indices had similar USDA-NRCS loss rating correspondence-60 and 64%, respectively. Analysis using Kendall's modified Tau suggested that correlations between measured and calculated P-loss ratings were similar or better for most P Indices than the models. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Comparison of digital radiography and apex locator with the conventional method in root length determination of primary teeth

    Directory of Open Access Journals (Sweden)

    I E Neena

    2011-01-01

    Full Text Available Aim: The purpose of this study was to compare the Working length in primary teeth endodontics using intra oral digital radiovisiography and apex locator with conventional method for accuracy. Materials and Methods: This in vivo study was conducted on 30 primary teeth which were indicated for pulpectomy in the patients of the age group of 5-11 years All experimental teeth had adequate remaining tooth structure for rubber dam isolation and radiographicaly visible canals. Endodontic treatment was required due to irreversible pulpitis or pulp necrosis. A standardized intraoral periapical radiograph of the tooth was taken using conventional method by paralleling technique. The distance between the source and the tooth, tooth and the films were standardized using X-ray positioning device. During the pulpectomy procedure, the working length was determined by digital radiograph and apex locator. The measurements were then compared with the conventional method of root canal measurement technique for accuracy Result: From the results obtained we can conclude that Working length determined in primary molars using digital radiography and Apex locator did not show any significant difference in the mean working length measurements when compared with the conventional radiographic method. Conclusions: Apex locator is comparable to conventional radiograph in determining the working length without radiation in the primary teeth. Intraoral digital radiography is the safest method in determining the working length with significant reduction in radiation exposure.Hence, both the techniques can be safely used as alternatives to conventional radiographic methods in determining working length in primary teeth.

  2. APEX sensitivity to atrazine dissipation rate on surface runoff loss within a coastal zone in Southeastern Puerto Rico

    Science.gov (United States)

    Simulation models are increasingly used to predict effects of conservation practices on transport of pesticides to water bodies. We used two models - the Agricultural Policy/Environmental eXtender (APEX) and the Riparian Ecosystem Management Model (REMM) to predict the movement of the herbicide, at...

  3. APEX simulation of runoff and total phosphorous for three adjacent row-crop watersheds with claypan soils

    Science.gov (United States)

    The Agricultural Policy Environmental Extender (APEX) model can simulate crop yields, runoff, and the transport of sediment and nutrients in small watersheds that have combinations of farm level landscapes, cropping systems and/or management practices. The objectives of the study were to parameteri...

  4. Evaluating the APEX model for simulating streamflow and water quality on ten agricultural watersheds in the U.S.

    Science.gov (United States)

    Simulation models are increasingly used to assess water quality constituent losses from agricultural systems. Mis-use often gives irrelevant or erroneous answers. The Agricultural Policy Environmental Extender (APEX) model is emerging as one of the premier modeling tools for fields, farms, and agr...

  5. Evaluation of the APEX model to simulate runoff quality from agricultural fields in the southern region of the US

    Science.gov (United States)

    The phosphorus (P) Index (PI) is the risk assessment tool approved in the NRCS 590 standard used to target critical source areas and practices to reduce P losses. A revision of the 590 standard, suggested using the Agricultural Policy/Environmental eXtender (APEX) model to assess the risk of nitroge...

  6. Development of a station based climate database for SWAT and APEX assessments in the U.S.

    Science.gov (United States)

    Water quality simulation models such as the Soil and Water Assessment Tool (SWAT) and Agricultural Policy EXtender (APEX) are widely used in the U.S. These models require large amounts of spatial and tabular data to simulate the natural world. Accurate and seamless daily climatic data are critical...

  7. Comparison of WEPP and APEX runoff and erosion prediction at field scale in Goodwater Creek Experimental Watershed

    Science.gov (United States)

    The Water Erosion Prediction Project (WEPP) and the Agricultural Policy/Environmental eXtender (APEX) are process-based models that can predict spatial and temporal distributions of erosion for hillslopes and watersheds. This study applies the WEPP model to predict runoff and erosion for a 35-ha fie...

  8. SU-F-P-61: Does It Matter Not to Use Optimization Points at the Apex for Vaginal Cylinder HDR Brachytherapy Planning?

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y [University Of Iowa, College of Medicine, Iowa City, IN (United States)

    2016-06-15

    Purpose: To test the impact of the use of apex optimization points for new vaginal cylinder (VC) applicators. Methods: New “ClickFit” single channel VC applicators (Varian) that have a different top thicknesses but the same diameters as the old VC applicators (2.3 cm diameter, 2.6 cm, 3.0 cm, and 3.5 cm) were compared using phantom studies. Old VC applicator plans without apex optimization points were also compared to the plans with the optimization points. The apex doses were monitored at 5 mm depth doses (8 points) where a prescription dose (Rx) of 6Gy was prescribed. VC surface doses (8 points) were also analyzed. Results: The new VC applicator plans without apex optimization points presented significantly lower 5mm depth doses than Rx (on average −31 ± 7%, p <0.00001) due to their thicker VC tops (3.4 ± 1.1 mm thicker with the range of 1.2 to 4.4 mm) than the old VC applicators. Old VC applicator plans also showed a statistically significant reduction (p <0.00001) due to Ir-192 source anisotropic effect at the apex region but the % reduction over Rx was only −7 ± 9%. However, by adding apex optimization points to the new VC applicator plans, the plans improved 5 mm depth doses (−7 ± 9% over Rx) that were not statistically different from old VC plans (p = 0.923), along with apex VC surface doses (−22 ± 10% over old VC versus −46 ± 7% without using apex optimization points). Conclusion: The use of apex optimization points are important in order to avoid significant additional cold doses (−24 ± 2%) at the prescription depth (5 mm) of apex, especially for the new VC applicators that have thicker tops.

  9. Comparative Transcriptome Analysis Reveal Candidate Genes Potentially Involved in Regulation of Primocane Apex Rooting in Raspberry (Rubus spp.).

    Science.gov (United States)

    Liu, Jianfeng; Ming, Yuetong; Cheng, Yunqing; Zhang, Yuchu; Xing, Jiyang; Sun, Yuqi

    2017-01-01

    Raspberries ( Rubus spp.) exhibit a unique rooting process that is initiated from the stem apex of primocane, conferring an unusual asexual mode of reproduction to this plant. However, the full complement of genes involved in this process has not been identified. To this end, the present study analyzed the transcriptomes of the Rubus primocane and floricane stem apex at three developmental stages by Digital Gene Expression profiling to identify genes that regulate rooting. Sequencing and de novo assembly yielded 26.82 Gb of nucleotides and 59,173 unigenes; 498, 7,346, 4,110, 7,900, 9,397, and 4,776 differently expressed genes were identified in paired comparisons of SAF1 (floricane at developmental stage 1) vs. SAP1 (primocane at developmental stage 1), SAF2 vs. SAP2, SAF3 vs. SAP3, SAP1 vs. SAP2, SAP1 vs. SAP3, and SAP2 vs. SAP3, respectively. SAP1 maintains an extension growth pattern; SAP2 then exhibits growth arrest and vertical (downward) gravitropic deflection; and finally, short roots begin to form on the apex of SAP3. The Kyoto Encyclopedia of Genes and Genomes enrichment analysis of SAP1 vs. SAP2 revealed 12 pathways that were activated in response to shoot growth arrest and root differentiation, including circadian rhythm-plant (ko04712) and plant hormone signal transduction (ko04075). Our results indicate that genes related to circadian rhythm, ethylene and auxin signaling, shoot growth, and root development are potentially involved in the regulation of primocane apex rooting in Rubus . These findings provide a basis for elucidating the molecular mechanisms of primocane apex rooting in this economically valuable crop.

  10. Characterization of liquid entrainment in the AP1000 automatic depressurization system from APEX tests

    International Nuclear Information System (INIS)

    Richard F Wright; Terry L Schulz; Jose N Reyes; John Groome

    2005-01-01

    Full text of publication follows: The AP1000 is a 1000 MWe advanced nuclear power plant that uses passive safety features to enhance plant safety and to provide significant and measurable improvements in plant simplification, reliability, investment protection and plant costs. The AP1000 relies heavily on the 600 MWe AP600 which received design certification in 1999. A critical part of the AP600 design certification process involved the testing of the passive safety systems. A one-fourth height, one-fourth pressure test facility, APEX-600, was constructed at the Oregon State University to study design basis events, and to provide a body of data to be used to validate the computer models used to analyze the AP600. This facility was extensively modified to reflect the design changes for AP1000 including higher power in the electrically heated rods representing the reactor core, and changes in the size of the pressurizer, core makeup tanks and automatic depressurization system. The APEX-1000 test facility was used to perform design basis accident simulations and separate effects tests to support the AP1000 design certification process. In the event of a LOCA, the AP1000 passive core cooling system provides sources of core makeup water along with an automatic depressurization system (ADS) consisting of several stages of valves which reduce the reactor coolant system pressure in a controlled manner. The final stage of this system, ADS-4, consists of four large valves that open off the hot legs, reducing the pressure to allow gravity injection from the in-containment refueling water storage tank (IRWST) and eventually the containment sump. The 67% increase in power from AP600 to AP1000 results in proportionally larger steam velocities exiting the core. Higher steam velocities could increases the potential for significant liquid entrainment out the ADS-4 lines, affecting the liquid inventory in the reactor. Tests were performed in APEX-1000 to characterize the two

  11. Reliable lateral and vertical manipulations of a single Cu adatom on a Cu(111) surface with multi-atom apex tip: semiempirical and first-principles simulations

    International Nuclear Information System (INIS)

    Xie Yiqun; Liu Qingwei; Zhang Peng; Wang Songyou; Li Yufen; Gan Fuxi; Zhuang Jun; Zhang Wenqing; Zhuang Min

    2008-01-01

    We study the reliability of the lateral manipulation of a single Cu adatom on a Cu(111) surface with single-atom, dimer and trimer apex tips using both semiempirical and first-principles simulations. The dependence of the manipulation reliability on tip height is investigated. For the single-atom apex tip the manipulation reliability increases monotonically with decreasing tip height. For the dimer and trimer apex tips the manipulation reliability is greatly improved compared to that for the single-atom apex tip over a certain tip-height range. Two kinds of mechanism are found responsible for this improvement. One is the so-called enhanced interaction mechanism in which the lateral tip-adatom interaction in the manipulation direction is improved. The other is the suspended atom mechanism in which the relative lateral trapping ability of the tip is improved due to the strong vertical attraction of the tip on the adatom. Both mechanisms occur in the manipulations with the trimer apex tip, while in those with the dimer apex tip only the former is effective. Moreover, we present a method to realize reversible vertical manipulation of a single atom on a Cu(111) surface with the trimer apex tip, based on its strong vertical and lateral attraction on the adatom

  12. Selenium and Mercury Interactions in Apex Predators from the Gulf of Trieste (Northern Adriatic Sea

    Directory of Open Access Journals (Sweden)

    Jadran Faganeli

    2018-02-01

    Full Text Available Since the environmental levels of selenium (Se can moderate the bioaccumulation and toxicity of mercury (Hg in marine organisms, their interactions were studied in seawater, sediments, plankton and the benthic (Bull ray Pteromylaeus bovinus, Eagle ray Myliobatis aquila and the pelagic (Pelagic stingray Dasyiatis violacea rays, as apex predators in the Gulf of Trieste (Northern Adriatic Sea. Male and female rays showed no difference in the Se contents in muscle tissue. Pelagic species contained higher Se levels in muscle but slightly lower levels in the livers of both genders. The Hg/Se ratios in seawater dissolved and colloidal fractions, plankton and sediment were <0.5, while those in particulate matter were <1.3. In benthic ray species, a parallel increase in Se and Hg in muscle was observed, so that an increased in Hg (MeHg bioaccumulation results in Se coaccumulation. The Hg/Se ratios (molar in muscle and liver of pelagic and benthic rays were <1.4 and <0.7, respectively. The low levels of Hg in muscle and liver in all the ray species corresponded to low Hg/Se ratios and increases in muscle and liver to 1 at 7 µg/g, dry weight (dw and 5 µg/g dw, respectively, i.e., about 1.6 µg/g wet weight (ww.

  13. Context Dependent Effect of Landscape on the Occurrence of an Apex Predator across Different Climate Regions.

    Science.gov (United States)

    Fujita, Go; Azuma, Atsuki; Nonaka, Jun; Sakai, Yoshiaki; Sakai, Hatsumi; Iseki, Fumitaka; Itaya, Hiroo; Fukasawa, Keita; Miyashita, Tadashi

    2016-01-01

    In studies of habitat suitability at landscape scales, transferability of species-landscape associations among sites are likely to be critical because it is often impractical to collect datasets across various regions. However, limiting factors, such as prey availability, are not likely to be constant across scales because of the differences in species pools. This is particularly true for top predators that are often the target for conservation concern. Here we focus on gray-faced buzzards, apex predators of farmland-dominated landscapes in East Asia. We investigated context dependency of "buzzard-landscape relationship", using nest location datasets from five sites, each differing in landscape composition. Based on the similarities of prey items and landscape compositions across the sites, we determined several alternative ways of grouping the sites, and then examined whether buzzard-landscape relationship change among groups, which was conducted separately for each way of grouping. As a result, the model of study-sites grouping based on similarities in prey items showed the smallest ΔAICc. Because the terms of interaction between group IDs and areas of broad-leaved forests and grasslands were selected, buzzard-landscape relationship showed a context dependency, i.e., these two landscape elements strengthen the relationship in southern region. The difference in prey fauna, which is associated with the difference in climate, might generate regional differences in the buzzard-landscape associations.

  14. Context Dependent Effect of Landscape on the Occurrence of an Apex Predator across Different Climate Regions.

    Directory of Open Access Journals (Sweden)

    Go Fujita

    Full Text Available In studies of habitat suitability at landscape scales, transferability of species-landscape associations among sites are likely to be critical because it is often impractical to collect datasets across various regions. However, limiting factors, such as prey availability, are not likely to be constant across scales because of the differences in species pools. This is particularly true for top predators that are often the target for conservation concern. Here we focus on gray-faced buzzards, apex predators of farmland-dominated landscapes in East Asia. We investigated context dependency of "buzzard-landscape relationship", using nest location datasets from five sites, each differing in landscape composition. Based on the similarities of prey items and landscape compositions across the sites, we determined several alternative ways of grouping the sites, and then examined whether buzzard-landscape relationship change among groups, which was conducted separately for each way of grouping. As a result, the model of study-sites grouping based on similarities in prey items showed the smallest ΔAICc. Because the terms of interaction between group IDs and areas of broad-leaved forests and grasslands were selected, buzzard-landscape relationship showed a context dependency, i.e., these two landscape elements strengthen the relationship in southern region. The difference in prey fauna, which is associated with the difference in climate, might generate regional differences in the buzzard-landscape associations.

  15. Evaluation of electrical impedance ratio measurements in accuracy of electronic apex locators.

    Science.gov (United States)

    Kim, Pil-Jong; Kim, Hong-Gee; Cho, Byeong-Hoon

    2015-05-01

    The aim of this paper was evaluating the ratios of electrical impedance measurements reported in previous studies through a correlation analysis in order to explicit it as the contributing factor to the accuracy of electronic apex locator (EAL). The literature regarding electrical property measurements of EALs was screened using Medline and Embase. All data acquired were plotted to identify correlations between impedance and log-scaled frequency. The accuracy of the impedance ratio method used to detect the apical constriction (APC) in most EALs was evaluated using linear ramp function fitting. Changes of impedance ratios for various frequencies were evaluated for a variety of file positions. Among the ten papers selected in the search process, the first-order equations between log-scaled frequency and impedance were in the negative direction. When the model for the ratios was assumed to be a linear ramp function, the ratio values decreased if the file went deeper and the average ratio values of the left and right horizontal zones were significantly different in 8 out of 9 studies. The APC was located within the interval of linear relation between the left and right horizontal zones of the linear ramp model. Using the ratio method, the APC was located within a linear interval. Therefore, using the impedance ratio between electrical impedance measurements at different frequencies was a robust method for detection of the APC.

  16. Spallator and APEX nuclear fuel cycle: a new option for nuclear power

    International Nuclear Information System (INIS)

    Steinberg, M.

    1982-01-01

    A new nuclear fuel cycle is described which provides a long term supply of nuclear fuel for the thermal LWR nuclear power reactors and eliminates the need for long-term storage of radioactive waste. Fissile fuel is produced by the Spallator which depends on the production of spallation neutrons by the interaction of high-energy (1 to 2 GeV) protons on a heavy-metal target. The neutrons are absorbed in a surrounding natural-uranium or thorium blanket in which fissile Pu-239 to U-233 is produced. Advances in linear accelerator technology makes it possible to design and construct a high-beam-current continuous-wave proton linac for production purposes. The target is similar to a sub-critical reactor and produces heat which is converted to electricity for supplying the linac. The Spallator is a self-sufficient fuel producer, which can compete with the fast breeder. The APEX fuel cycle depends on recycling the transuranics and long-lived fission products while extracting the stable and short-lived fission products when reprocessing the fuel. Transmutation and decay within the fuel cycle and decay of short-lived fission products external to the fuel cycle eliminates the need for long-term geological age shortage of fission-product waste

  17. General Dental Practitioners’ Concept towards Using Radiography and Apex-Locators in Endodontics

    Science.gov (United States)

    Raoof, Maryam; Heidaripour, Maryam; Shahravan, Arash; Haghani, Jahangir; Afkham, Arash; Razifar, Mahsa; Mohammadizadeh, Sakineh

    2014-01-01

    Introduction: Despite being the gold standard as well as a routine technique in endodontics, radiographic working length (WL) determination owns many drawbacks. Electronic apex-locators (EALs) are recommended to complement radiographies. The aim of this study was to evaluate the perceptions of Iranian general dental practitioners (GDPs) towards using radiography and EAL. Methods and Materials: Three hundred and ninety one GDPs attending the 53th Iranian Dental Association Congress completed a questionnaire focusing on the use of radiography and EALs during the various stages of root canal treatment. The data was analyzed with the chi-square test with the level of significance set at 0.05. The results were then calculated as frequencies and percentages. Results: More than half of the GDPs reported using radiographs as the sole method for WL determination. A total of 30.4% of the practitioners were using the combined approach during root canal therapy of a single-rooted tooth, while 38.9% used this method in multi-rooted teeth. Approximately half of the respondents would not order follow-up radiographies after root canal treatment. Conclusion: Radiography continues to be the most common method for WL determination in Iran. PMID:25386209

  18. Evaluation of electrical impedance ratio measurements in accuracy of electronic apex locators

    Directory of Open Access Journals (Sweden)

    Pil-Jong Kim

    2015-05-01

    Full Text Available Objectives The aim of this paper was evaluating the ratios of electrical impedance measurements reported in previous studies through a correlation analysis in order to explicit it as the contributing factor to the accuracy of electronic apex locator (EAL. Materials and Methods The literature regarding electrical property measurements of EALs was screened using Medline and Embase. All data acquired were plotted to identify correlations between impedance and log-scaled frequency. The accuracy of the impedance ratio method used to detect the apical constriction (APC in most EALs was evaluated using linear ramp function fitting. Changes of impedance ratios for various frequencies were evaluated for a variety of file positions. Results Among the ten papers selected in the search process, the first-order equations between log-scaled frequency and impedance were in the negative direction. When the model for the ratios was assumed to be a linear ramp function, the ratio values decreased if the file went deeper and the average ratio values of the left and right horizontal zones were significantly different in 8 out of 9 studies. The APC was located within the interval of linear relation between the left and right horizontal zones of the linear ramp model. Conclusions Using the ratio method, the APC was located within a linear interval. Therefore, using the impedance ratio between electrical impedance measurements at different frequencies was a robust method for detection of the APC.

  19. Spallator and APEX nuclear fuel cycle: a new option for nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    Steinberg, M.

    1982-01-01

    A new nuclear fuel cycle is described which provides a long term supply of nuclear fuel for the thermal LWR nuclear power reactors and eliminates the need for long-term storage of radioactive waste. Fissile fuel is produced by the Spallator which depends on the production of spallation neutrons by the interaction of high-energy (1 to 2 GeV) protons on a heavy-metal target. The neutrons are absorbed in a surrounding natural-uranium or thorium blanket in which fissile Pu-239 to U-233 is produced. Advances in linear accelerator technology makes it possible to design and construct a high-beam-current continuous-wave proton linac for production purposes. The target is similar to a sub-critical reactor and produces heat which is converted to electricity for supplying the linac. The Spallator is a self-sufficient fuel producer, which can compete with the fast breeder. The APEX fuel cycle depends on recycling the transuranics and long-lived fission products while extracting the stable and short-lived fission products when reprocessing the fuel. Transmutation and decay within the fuel cycle and decay of short-lived fission products external to the fuel cycle eliminates the need for long-term geological age shortage of fission-product waste.

  20. Cost analysis of a disaster facility at an apex tertiary care trauma center of India

    Directory of Open Access Journals (Sweden)

    Sheetal Singh

    2016-01-01

    Full Text Available Introduction: For the Commonwealth Games 2010, Jai Prakash Narayan Apex Trauma Centre (JPNATC of India had been directed by the Director General Health Services and Ministry of Health and Family Welfare, Government of India, to set up a specialized unit for the definitive management of the injured/unwell athletes, officials, and related personnel coming for the Commonwealth Games in October 2010. The facility included a 20-bedded fully equipped ward, six ICU beds with ventilator capacity, one very very important person observation area, one perioperative management cubicle, and one fully modular and integrated operating room. Objective: The objective of this study was to calculate the cost of disaster facility at JPNATC, All India Institute of Medical Sciences, New Delhi. Methodology: Traditional (average or gross costing methodology was used to arrive at the cost for the provisioning of these services by this facility. Results: The annual cost of providing services at disaster facility at JPNATC, New Delhi, was calculated to be INR 61,007,334.08 (US$ 983,989.258 while the per hour cost was calculated to be INR 7061.03 of the total cost toward the provisioning of services by disaster facility where 26% was the capital cost and 74% was the operating cost. Human resource caters to maximum chunk of the expenditures (47%. Conclusion: The results of this costing study will help in the future planning of resource allocation within the financial constraints (US$ 1 = INR 62 in the year 2013.

  1. Cost analysis of a disaster facility at an apex tertiary care trauma center of India.

    Science.gov (United States)

    Singh, Sheetal; Gupta, Shakti; Daga, Anoop; Siddharth, Vijaydeep; Wundavalli, LaxmiTej

    2016-01-01

    For the Commonwealth Games 2010, Jai Prakash Narayan Apex Trauma Centre (JPNATC) of India had been directed by the Director General Health Services and Ministry of Health and Family Welfare, Government of India, to set up a specialized unit for the definitive management of the injured/unwell athletes, officials, and related personnel coming for the Commonwealth Games in October 2010. The facility included a 20-bedded fully equipped ward, six ICU beds with ventilator capacity, one very very important person observation area, one perioperative management cubicle, and one fully modular and integrated operating room. The objective of this study was to calculate the cost of disaster facility at JPNATC, All India Institute of Medical Sciences, New Delhi. Traditional (average or gross) costing methodology was used to arrive at the cost for the provisioning of these services by this facility. The annual cost of providing services at disaster facility at JPNATC, New Delhi, was calculated to be INR 61,007,334.08 (US$ 983,989.258) while the per hour cost was calculated to be INR 7061.03 of the total cost toward the provisioning of services by disaster facility where 26% was the capital cost and 74% was the operating cost. Human resource caters to maximum chunk of the expenditures (47%). The results of this costing study will help in the future planning of resource allocation within the financial constraints (US$ 1 = INR 62 in the year 2013).

  2. Deblending using an improved apex-shifted hyperbolic radon transform based on the Stolt migration operator

    Science.gov (United States)

    Gong, Xiangbo; Feng, Fei; Jiao, Xuming; Wang, Shengchao

    2017-10-01

    Simultaneous seismic source separation, also known as deblending, is an essential process for blended acquisition. With the assumption that the blending noise is coherent in the common shot domain but is incoherent in other domains, traditional deblending methods are commonly performed in the common receiver, common midpoint or common offset domain. In this paper, we propose an improved apex-shifted hyperbolic radon transform (ASHRT) to deblend directly in the common shot domain. A time-axis stretch strategy named Stolt-stretch is introduced to overcome the limitation of the constant velocity assumption of Stolt-based operators. To improve the sparsity in the transform domain, a total variation (TV) norm inversion is implemented to enhance the energy convergence in the radon panel. Because of highly efficient Stolt migration and the demigration operator in the frequency-wavenumber domain, as well as the flexible geometry condition of the source-receiver, this approach is quite suitable for quality control (QC) during streamer acquisition. The synthetic and field examples demonstrate that our proposition is robust and efficient.

  3. Inhibition of white light of 86Rb+ absorption in the root apex of corn

    International Nuclear Information System (INIS)

    McKendree, W.L.; Smith, R.C.

    1990-01-01

    Measurements of cell lengths made at 0.5 millimeter intervals in median longitudinal sections of the primary roots of corn (Zea mays) were used to construct a growth curve. The region 1.5 to 4.0 millimeters from the apex contained the largest number of elongating cells. Absorption of 86 Rb + was measured using intact, dark-grown corn seedlings. Following uptake and exchange, the terminal 8.0 millimeters of each root was cut into four 2.0 millimeter segments. Maximum 86 Rb + uptake occurred in the region from 0.0 to 4.0 millimeter from the root tip. Washing the intact primary root in fresh 2.0 millimolar CaSO 4 for 2 hours prior to uptake augmented the rate of 86 Rb + uptake in all regions. Illumination with white light during washing caused a reduction of 86 Rb + uptake as compared with controls washing in darkness, and the region of greatest light response was the region of elongation. Removal of the coleoptile prior to washing did not prevent the light inhibition of subsequent 86 Rb + uptake. Removal of the root cap prior to washing in light partially reversed the light-induced inhibition of the washing response

  4. Endoscopic endonasal anatomy of superior orbital fissure and orbital apex regions: critical considerations for clinical applications.

    Science.gov (United States)

    Dallan, Iacopo; Castelnuovo, Paolo; de Notaris, Matteo; Sellari-Franceschini, Stefano; Lenzi, Riccardo; Turri-Zanoni, Mario; Battaglia, Paolo; Prats-Galino, Alberto

    2013-05-01

    The superior orbital fissure is a critical three-dimensional space connecting the middle cranial fossa and the orbit. From an endoscopic viewpoint, only the medial aspect has a clinical significance. It presents a critical relationship with the lateral sellar compartment, the pterygopalatine fossa and the middle cranial fossa. The connective tissue layers and neural and vascular structures of this region are described. The role of Muller's muscle is confirmed, and the utility of the maxillary and optic strut is outlined. Muller's muscle extends for the whole length of the inferior orbital fissure, passes over the maxillary strut and enters the superior orbital fissure, representing a critical surgical landmark. Dividing the tendon between the medial and inferior rectus muscle allows the identification of the main trunk of the oculomotor nerve, and a little laterally, it is usually possible to visualize the first part of the ophthalmic artery. Based on a better knowledge of anatomy, we trust that this area could be readily addressed in clinical situations requiring an extended approach in proximity of the orbital apex.

  5. Chemistry Characterization of Jet Aircraft Engine Particulate by XPS: Results from APEX III

    Science.gov (United States)

    Vander Wal, Randy L.; Bryg, Victoria M.

    2014-01-01

    This paper reports XPS analysis of jet exhaust particulate from a B737, Lear, ERJ, and A300 aircraft during the APEX III NASA led field campaign. Carbon hybridization and bonding chemistry are identified by high-resolution scans about the C1s core-shell region. Significant organic content as gauged by the sp3/sp2 ratio is found across engines and platforms. Polar oxygen functional groups include carboxylic, carbonyl and phenol with combined content of 20 percent or more. By lower resolution survey scans various elements including transition metals are identified along with lighter elements such as S, N, and O in the form of oxides. Burning additives within lubricants are probable sources of Na, Ba, Ca, Zn, P and possibly Sn. Elements present and their percentages varied significantly across all engines, not revealing any trend or identifiable cause for the differences, though the origin is likely the same for the same element when observed. This finding suggests that their presence can be used as a tracer for identifying soots from aircraft engines as well as diagnostic for monitoring engine performance and wear.

  6. APEX_SCOPE: A graphical user interface for visualization of multi-modal data in inter-disciplinary studies.

    Science.gov (United States)

    Kanbar, Lara J; Shalish, Wissam; Precup, Doina; Brown, Karen; Sant'Anna, Guilherme M; Kearney, Robert E

    2017-07-01

    In multi-disciplinary studies, different forms of data are often collected for analysis. For example, APEX, a study on the automated prediction of extubation readiness in extremely preterm infants, collects clinical parameters and cardiorespiratory signals. A variety of cardiorespiratory metrics are computed from these signals and used to assign a cardiorespiratory pattern at each time. In such a situation, exploratory analysis requires a visualization tool capable of displaying these different types of acquired and computed signals in an integrated environment. Thus, we developed APEX_SCOPE, a graphical tool for the visualization of multi-modal data comprising cardiorespiratory signals, automated cardiorespiratory metrics, automated respiratory patterns, manually classified respiratory patterns, and manual annotations by clinicians during data acquisition. This MATLAB-based application provides a means for collaborators to view combinations of signals to promote discussion, generate hypotheses and develop features.

  7. Comparative evaluation of accuracy of two electronic apex locators in the presence of various irrigants: An in vitro study

    Directory of Open Access Journals (Sweden)

    Saru Jain

    2012-01-01

    Full Text Available Context: The establishment of appropriate working length is one of the most critical steps in endodontic therapy. Electronic apex locators have been introduced to determine the working length. The development of electronic apex locators has helped make the assessment of the working length more accurate and predictable, along with reduction in treatment time and radiation dose. Objectives: The aim of this study was to compare the efficacy of electronic apex locators after cleansing and shaping of the root canals and whether there was any alteration in accuracy when used in the presence of irrigants. Materials and Methods: Seventy extracted human permanent molars with mature apices were selected. Equal number of maxillary and mandibular permanent molars (35 each were sectioned at the cemento-enamel junction. Access opening was done and only the mesiobuccal root canal was studied for the purpose of standardization. Electronic working length measurements were taken before and after preparation of the mesiobuccal canal with Root ZX and ProPex II using various irrigants. Statistical Analysis Used: The data were statistically analyzed using a paired t-test at 0.05 level of significance. Results: P-values for actual and final canal lengths for Root ZX employing NaoCl(0.001, CHX(0.006, LA(0.020 and for ProPex II was (0.001 respectively. When the data were compared, results were statistically significant (P < 0.05. Conclusion: Within the limitations of this study Root ZX can be considered to be an accurate electronic apex locator and CHX as irrigant matched more precisely with the actual canal length measurements.

  8. Dexamethasone levels and base to apex concentration gradients in scala tympani perilymph following intracochlear delivery in the guinea pig

    Science.gov (United States)

    Hahn, Hartmut; Salt, Alec N.; Biegner, Thorsten; Kammerer, Bernd; Delabar, Ursular; Hartsock, Jared; Plontke, Stefan K.

    2012-01-01

    Hypothesis To determine whether intracochlearly applied dexamethasone will lead to better control of drug levels, higher peak concentrations and lower base-to apex concentration gradients in scala tympani (ST) of the guinea pig than after intratympanic (round window, RW) application. Background Local application of drugs to the RW results in substantial variation of intracochlear drug levels and significant base-to apex concentration gradients in ST. Methods Two μL of dexamethasone-phosphate (10 mg/mL) were injected into ST either through the RW membrane which was covered with 1% sodium hyaluronate gel or through a cochleostomy with a fluid tight seal of the micropipette. Perilymph was sequentially sampled from the apex at a single time point for each animal, at 20, 80, or 200 min after the injection ended. Results were mathematically interpreted by the means of an established computer model and compared with prior experiments performed by our group with the same experimental techniques but using intratympanic applications. Results Single intracochlear injections over 20 min resulted in approximately ten times higher peak concentrations (on average) than 2-3 hours of intratympanic application to the round window niche. Intracochlear drug levels were less variable and could be measured for at least up to 220 min. Concentration gradients along scala tympani were less pronounced. The remaining variability in intracochlear drug levels was attributable to perilymph and drug leak from the injection site. Conclusion With significantly higher, less variable drug levels and smaller base-to apex concentration gradients, intracochlear applications have advantages to intratympanic injections. For further development of this technique, it is of importance to control leaks of perilymph and drug from the injection site and to evaluate its clinical feasibility and associated risks. PMID:22588238

  9. Classification of High-Mountain Vegetation Communities within a Diverse Giant Mountains Ecosystem Using Airborne APEX Hyperspectral Imagery

    Directory of Open Access Journals (Sweden)

    Adriana Marcinkowska-Ochtyra

    2018-04-01

    Full Text Available Mapping plant communities is a difficult and time consuming endeavor. Methods relying on field surveys deliver high quality data but are usually limited to relatively small areas. In this paper we apply airborne hyperspectral data to vegetation mapping in remote and hard to reach areas. We classified 22 vegetation communities in the Giant Mountains on 3.12-m Airborne Prism Experiment (APEX hyperspectral images, registered in 288 spectral bands (10 September 2012. As the classification algorithm, Support Vector Machines (SVM was used. APEX data were corrected geometrically and atmospherically, and three dimensionality reduction methods were performed to select the best dataset. As reference we used a non-forest vegetation map containing vegetation communities of Polish Karkonosze National Park from 2002, orthophotomap and field surveys data from 2013 to 2014. We obtained the post-classification maps of 22 vegetation communities, lakes and areas without any vegetation. Iterative accuracy assessment repeated 100 times was used to obtain the most objective results for individual communities. The median value of overall accuracy (OA was 84%. Fourteen out of twenty-four classes were classified of more than 80% of producer accuracy (PA and sixteen out of twenty-four of user accuracy (UA. APEX data and SVM with the use of iterative accuracy assessment are useful for the mountain communities classification. This can support both Polish and Czech national parks management by giving the information about diversity of communities in the whole transboundary area, helping with identification especially in changing environment caused by humans.

  10. APEX-CAMBIUM: A Case Study in Advantages and Challenges of International Cooperation for the International Space Station

    Science.gov (United States)

    Cox, David; Buckley, Nicole

    2008-01-01

    It is generally agreed that space science benefits from an international collaboration. There are different mechanisms to make this happen but to recognize opportunities requires a keen awareness of the activities, people and respective strengths. Apex- Cambium is a joint Canadian Space Agency (CSA)-National Aeronautics and Space Administration (NASA) initiative. It was made possible in large part through the good relations and shared willingness to meet a common objective, that of doing exciting science in space. The actual mechanics of bringing an international project together can be divided into two perspectives: programmatic and implementation. The programmatic component includes recognizing complementarities, bringing science together, and the need to have Agencies approve and accept joint responsibility for the mission. The implementation component involves working to define science requirements, available resources and assigning individual responsibilities while keeping the overall success criteria as a collective objective. The APEX-CAMB11.JM mission will be described from the point of view of both CSA and NASA. Suggestions on how to facilitate these types of initiatives will be provided and highlights of the APEX-Cambium collaboration will be provided.

  11. Should the tip-apex distance (TAD) rule be modified for the proximal femoral nail antirotation (PFNA)? A retrospective study.

    Science.gov (United States)

    Nikoloski, Andrej N; Osbrough, Anthony L; Yates, Piers J

    2013-10-17

    Unstable proximal femoral fractures are common and challenging for the orthopaedic surgeon. Often, these are treated with intramedullary nails. The most common mode of failure of any device to treat these fractures is cut-out. The Synthes proximal femoral nail antirotation (PFNA) is unique because it is the only proximal femoral intramedullary nail which employs a helical blade in lieu of a lag screw. The optimal tip-apex distance is 25 mm or less for a dynamic hip screw. The optimal blade tip placement is not known for the PFNA. The aim of this study is to determine if the traditional tip-apex distance rule (TAD) less than 20 mm. There was no cut-out in cases where the TAD was from 20-30 mm. There were three implant-related failures (nail fracture, missed nail and loose locking screw), four implant-related femoral fractures, two non-unions, two delayed unions and one loss of reduction. The PFNA is a suitable fixation device for the treatment of unstable proximal femoral fractures. There were still a relatively large number of cut-outs, and the tip-apex distance in the failures showed a bimodal distribution, not like previously demonstrated with dynamic hip screw. We propose that the helical blade behaves differently to a screw, and placement too close to the subchondral bone may lead to penetration through the head.

  12. Selective deintercalation of apex over face-shared oxide ions in the topotactic reduction of Sr7Mn4O15 to Sr7Mn4O12.

    Science.gov (United States)

    Hayward, M A

    2004-01-21

    Sodium hydride selectively deintercalates the apex rather than face-shared oxide ions within the structure of Sr(7)Mn(4)O(15) leading to the formation of the structurally related reduced phase Sr(7)Mn(4)O(12).

  13. Cone Beam Computed Tomography Evaluation of the Periapical Status of Nonvital Tooth with Open Apex Obturated with Mineral Trioxide Aggregate: A Case Report

    Directory of Open Access Journals (Sweden)

    Vijay Shekhar

    2013-01-01

    Full Text Available Management of a tooth with open apex is a challenge to the dental practitioners. Evaluation of the periapical healing is required in such cases by radiographic techniques. The objective of this paper was to assess the healing of a periapical lesion in a non-vital tooth with open apex treated with mineral trioxide aggregate (MTA obturation using cone beam computed tomography (CBCT. The endodontic treatment of a fractured non-vital discolored maxillary left lateral incisor with an open apex was done with MTA obturation. The clinical and radiographic followup done regularly showed that the tooth was clinically asymptomatic and that the size of the periapical lesion observed by intraoral periapical (IOPA radiographs and CBCT was decreased remarkably after two years. CBCT and IOPA radiographs were found to be useful radiographic tools to assess the healing of a large periapical lesion in a non-vital tooth with open apex managed by MTA obturation.

  14. A HERSCHEL AND APEX CENSUS OF THE REDDEST SOURCES IN ORION: SEARCHING FOR THE YOUNGEST PROTOSTARS

    Energy Technology Data Exchange (ETDEWEB)

    Stutz, Amelia M.; Robitaille, Thomas; Henning, Thomas; Krause, Oliver [Max Planck Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Tobin, John J. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Stanke, Thomas [ESO, Karl-Schwarzschild-Strasse 2, D-85748 Garching bei Muenchen (Germany); Megeath, S. Thomas; Fischer, William J. [Department of Physics and Astronomy, University of Toledo, 2801 W. Bancroft Street, Toledo, OH 43606 (United States); Ali, Babar; Furlan, Elise [NHSC/IPAC/Caltech, 770 S. Wilson Avenue, Pasadena, CA 91125 (United States); Di Francesco, James [National Research Council of Canada, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Hartmann, Lee [Department of Astronomy, University of Michigan, 830 Dennison Building, 500 Church Street, Ann Arbor, MI 48109 (United States); Osorio, Mayra [Instituto de Astrofisica de Andalucia, CSIC, Camino Bajo de Huetor 50, E-18008 Granada (Spain); Wilson, Thomas L. [Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375 (United States); Allen, Lori [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Manoj, P., E-mail: stutz@mpia.de [Department of Physics and Astronomy, 500 Wilson Boulevard, University of Rochester, Rochester, NY 14627 (United States)

    2013-04-10

    We perform a census of the reddest, and potentially youngest, protostars in the Orion molecular clouds using data obtained with the PACS instrument on board the Herschel Space Observatory and the LABOCA and SABOCA instruments on APEX as part of the Herschel Orion Protostar Survey (HOPS). A total of 55 new protostar candidates are detected at 70 {mu}m and 160 {mu}m that are either too faint (m{sub 24} > 7 mag) to be reliably classified as protostars or undetected in the Spitzer/MIPS 24 {mu}m band. We find that the 11 reddest protostar candidates with log {lambda}F{sub {lambda}}70/{lambda}F{sub {lambda}}24 > 1.65 are free of contamination and can thus be reliably explained as protostars. The remaining 44 sources have less extreme 70/24 colors, fainter 70 {mu}m fluxes, and higher levels of contamination. Taking the previously known sample of Spitzer protostars and the new sample together, we find 18 sources that have log {lambda}F{sub {lambda}}70/{lambda}F{sub {lambda}}24 > 1.65; we name these sources 'PACS Bright Red sources', or PBRs. Our analysis reveals that the PBR sample is composed of Class 0 like sources characterized by very red spectral energy distributions (SEDs; T{sub bol} < 45 K) and large values of sub-millimeter fluxes (L{sub smm}/L{sub bol} > 0.6%). Modified blackbody fits to the SEDs provide lower limits to the envelope masses of 0.2-2 M{sub Sun} and luminosities of 0.7-10 L{sub Sun }. Based on these properties, and a comparison of the SEDs with radiative transfer models of protostars, we conclude that the PBRs are most likely extreme Class 0 objects distinguished by higher than typical envelope densities and hence, high mass infall rates.

  15. Agrobacterium-mediated transformation of finger millet (Eleusine coracana (L.) Gaertn.) using shoot apex explants.

    Science.gov (United States)

    Ceasar, S Antony; Ignacimuthu, S

    2011-09-01

    A new Agrobacterium-mediated transformation system was developed for finger millet using shoot apex explants. The Agrobacterium strain LBA4404 harboring binary vector pCAMBIA1301, which contained hygromycin phosphotransferase (hptII) as selectable marker gene and β-glucuronidase (GUS) as reporter gene, was used for optimization of transformation conditions. Two finger millet genotypes, GPU 45 and CO 14, were used in this study. The optimal conditions for the Agrobacterium-mediated transformation of finger millet were found to be the co-cultivation of explants obtained on the 16th day after callus induction (DACI), exposure of explants for 30 min to agrobacterial inoculum and 3 days of co-cultivation on filter paper placed on medium supplemented with 100 μM acetosyringone (AS). Addition of 100 μM L: -cysteine in the selection medium enhanced the frequency of transformation and transgenic plant recovery. Both finger millet genotypes were transformed by Agrobacterium. A frequency of 19% transient expression with 3.8% stable transformation was achieved in genotype GPU 45 using optimal conditions. Five stably transformed plants were fully characterized by Southern blot analysis. A segregation analysis was also performed in four R(1) progenies, which showed normal Mendelian pattern of transgene segregation. The inheritance of transgenes in R(1) progenies was also confirmed by Southern blot analysis. This is the first report on Agrobacterium-mediated transformation of finger millet. This study underpins the introduction of numerous agronomically important genes into the genome of finger millet in the future.

  16. Residency and movement patterns of an apex predatory shark (Galeocerdo cuvier at the Galapagos Marine Reserve.

    Directory of Open Access Journals (Sweden)

    David Acuña-Marrero

    Full Text Available The potential effectiveness of marine protected areas (MPAs as a conservation tool for large sharks has been questioned due to the limited spatial extent of most MPAs in contrast to the complex life history and high mobility of many sharks. Here we evaluated the movement dynamics of a highly migratory apex predatory shark (tiger shark Galeocerdo cuvier at the Galapagos Marine Reserve (GMR. Using data from satellite tracking passive acoustic telemetry, and stereo baited remote underwater video, we estimated residency, activity spaces, site fidelity, distributional abundances and migration patterns from the GMR and in relation to nesting beaches of green sea turtles (Chelonia mydas, a seasonally abundant and predictable prey source for large tiger sharks. Tiger sharks exhibited a high degree of philopatry, with 93% of the total satellite-tracked time across all individuals occurring within the GMR. Large sharks (> 200 cm TL concentrated their movements in front of the two most important green sea turtle-nesting beaches in the GMR, visiting them on a daily basis during nocturnal hours. In contrast, small sharks (< 200 cm TL rarely visited turtle-nesting areas and displayed diurnal presence at a third location where only immature sharks were found. Small and some large individuals remained in the three study areas even outside of the turtle-nesting season. Only two sharks were satellite-tracked outside of the GMR, and following long-distance migrations, both individuals returned to turtle-nesting beaches at the subsequent turtle-nesting season. The spatial patterns of residency and site fidelity of tiger sharks suggest that the presence of a predictable source of prey and suitable habitats might reduce the spatial extent of this large shark that is highly migratory in other parts of its range. This highly philopatric behaviour enhances the potential effectiveness of the GMR for their protection.

  17. UFO in the Arabidopsis inflorescence apex is required for floral-meristem identity and bract suppression.

    Science.gov (United States)

    Hepworth, Shelley R; Klenz, Jennifer E; Haughn, George W

    2006-03-01

    The UNUSUAL FLORAL ORGANS (UFO) gene of Arabidopsis encodes an F-box protein required for the determination of floral-organ and floral-meristem identity. Mutation of UFO leads to dramatic changes in floral-organ type which are well-characterized whereas inflorescence defects are more subtle and less understood. These defects include an increase in the number of secondary inflorescences, nodes that alternate between forming flowers and secondary inflorescences, and nodes in which a single flower is subtended by a bract. Here, we show how inflorescence defects correlate with the abnormal development of floral primordia and establish a temporal requirement for UFO in this process. At the inflorescence apex of ufo mutants, newly formed primordia are initially bract-like. Expression of the floral-meristem identity genes LFY and AP1 are confined to a relatively small adaxial region of these primordia with expression of the bract-identity marker FIL observed in cells that comprise the balance of the primordia. Proliferation of cells in the adaxial region of these early primordia is delayed by several nodes such that primordia appear "chimeric" at several nodes, having visible floral and bract components. However, by late stage 2 of floral development, growth of the bract generally ceases and is overtaken by development of the floral primordium. This abnormal pattern of floral meristem development is not rescued by expression of UFO from the AP1 promoter, indicating that UFO is required prior to AP1 activation for normal development of floral primordia. We propose that UFO and LFY are jointly required in the inflorescence meristem to both promote floral meristem development and inhibit, in a non-cell autonomous manner, growth of the bract.

  18. Two- versus four-handed techniques for endonasal resection of orbital apex tumors.

    Science.gov (United States)

    Craig, John R; Lee, John Y K; Petrov, Dmitriy; Mehta, Sonul; Palmer, James N; Adappa, Nithin D

    2015-01-01

    Open versus endonasal resection of orbital apex (OA) tumors is generally based on tumor size, location, and pathology. For endonasal resection, two- and four-handed techniques have been reported, but whether one technique is more optimal based on these tumor features has not been evaluated. To determine whether two- versus four-handed techniques result in better outcomes after endoscopic resection of OA tumors, and whether either technique is better suited for intra- versus extraconal location and for benign versus malignant pathology. A retrospective review of all expanded endonasal approaches for OA tumors was performed at a single institution from 2009 to 2013. A PubMed database search was also performed to review series published on endonasal OA tumor resection. Across all the cases reviewed, the following data were recorded: two- versus four-handed techniques, intra- versus extraconal tumor location, and benign versus malignant pathology. The relationship between these variables and resection extent was analyzed by the Fisher exact test. Postoperative visual status and complications were also reviewed. Ten cases from the institution and 94 cases from 17 publications were reviewed. Both two- and four-handed techniques were used to resect extra- and intraconal OA tumors, for both benign and malignant pathology. Four-handed techniques included a purely endonasal approach and a combined endonasal-orbital approach. On univariate analysis, the strongest predictor of complete resection was benign pathology (p = 0.005). No significant difference was found between the extent of resection and a two- versus a four-handed technique. Visual status was improved or unchanged in 94% of cases, and other complications were rare. Benign tumors that involve the medial extraconal and posterior inferomedial intraconal OA can be treated by either two- or four-handed endonasal techniques. Selecting two- versus four-handed techniques and endonasal versus endonasal-orbital four

  19. Platelet-biased stem cells reside at the apex of the haematopoietic stem-cell hierarchy.

    Science.gov (United States)

    Sanjuan-Pla, Alejandra; Macaulay, Iain C; Jensen, Christina T; Woll, Petter S; Luis, Tiago C; Mead, Adam; Moore, Susan; Carella, Cintia; Matsuoka, Sahoko; Bouriez Jones, Tiphaine; Chowdhury, Onima; Stenson, Laura; Lutteropp, Michael; Green, Joanna C A; Facchini, Raffaella; Boukarabila, Hanane; Grover, Amit; Gambardella, Adriana; Thongjuea, Supat; Carrelha, Joana; Tarrant, Paul; Atkinson, Deborah; Clark, Sally-Ann; Nerlov, Claus; Jacobsen, Sten Eirik W

    2013-10-10

    The blood system is maintained by a small pool of haematopoietic stem cells (HSCs), which are required and sufficient for replenishing all human blood cell lineages at millions of cells per second throughout life. Megakaryocytes in the bone marrow are responsible for the continuous production of platelets in the blood, crucial for preventing bleeding--a common and life-threatening side effect of many cancer therapies--and major efforts are focused at identifying the most suitable cellular and molecular targets to enhance platelet production after bone marrow transplantation or chemotherapy. Although it has become clear that distinct HSC subsets exist that are stably biased towards the generation of lymphoid or myeloid blood cells, we are yet to learn whether other types of lineage-biased HSC exist or understand their inter-relationships and how differently lineage-biased HSCs are generated and maintained. The functional relevance of notable phenotypic and molecular similarities between megakaryocytes and bone marrow cells with an HSC cell-surface phenotype remains unclear. Here we identify and prospectively isolate a molecularly and functionally distinct mouse HSC subset primed for platelet-specific gene expression, with enhanced propensity for short- and long-term reconstitution of platelets. Maintenance of platelet-biased HSCs crucially depends on thrombopoietin, the primary extrinsic regulator of platelet development. Platelet-primed HSCs also frequently have a long-term myeloid lineage bias, can self-renew and give rise to lymphoid-biased HSCs. These findings show that HSC subtypes can be organized into a cellular hierarchy, with platelet-primed HSCs at the apex. They also demonstrate that molecular and functional priming for platelet development initiates already in a distinct HSC population. The identification of a platelet-primed HSC population should enable the rational design of therapies enhancing platelet output.

  20. Spring fasting behavior in a marine apex predator provides an index of ecosystem productivity

    Science.gov (United States)

    Rode, Karyn D.; Wilson, Ryan R.; Douglas, David C.; Muhlenbruch, Vanessa L; Atwood, Todd C.; Regehr, Eric V.; Richardson, Evan; Pilfold, Nicholas; Derocher, Andrew E.; Durner, George M.; Stirling, Ian; Amstrup, Steven C.; St Martin, Michelle; Pagano, Anthony M.; Simac, Kristin

    2018-01-01

    The effects of declining Arctic sea ice on local ecosystem productivity are not well understood but have been shown to vary inter-specifically, spatially, and temporally. Because marine mammals occupy upper trophic levels in Arctic food webs, they may be useful indicators for understanding variation in ecosystem productivity. Polar bears (Ursus maritimus) are apex predators that primarily consume benthic and pelagic-feeding ice-associated seals. As such, their productivity integrates sea ice conditions and the ecosystem supporting them. Declining sea ice availability has been linked to negative population effects for polar bears but does not fully explain observed population changes. We examined relationships between spring foraging success of polar bears and sea ice conditions, prey productivity, and general patterns of ecosystem productivity in the Beaufort and Chukchi Seas (CSs). Fasting status (≥7 days) was estimated using serum urea and creatinine levels of 1,448 samples collected from 1,177 adult and subadult bears across three subpopulations. Fasting increased in the Beaufort Sea between 1983–1999 and 2000–2016 and was related to an index of ringed seal body condition. This change was concurrent with declines in body condition of polar bears and observed changes in the diet, condition and/or reproduction of four other vertebrate consumers within the food chain. In contrast, fasting declined in CS polar bears between periods and was less common than in the two Beaufort Sea subpopulations consistent with studies demonstrating higher primary productivity and maintenance or improved body condition in polar bears, ringed seals, and bearded seals despite recent sea ice loss in this region. Consistency between regional and temporal variation in spring polar bear fasting and food web productivity suggests that polar bears may be a useful indicator species. Furthermore, our results suggest that spatial and temporal ecological variation is important in

  1. Mapping of the Tropospheric NO2 Spatial Distribution at City-scale Based on Airborne APEX Hyperspectral Imaging

    Science.gov (United States)

    Tack, F. M.; Merlaud, A.; Danckaert, T.; Yu, H.; Fayt, C.; Iordache, D.; Meuleman, K.; Fierens, F.; Deutsch, F.; Van Roozendael, M.

    2016-12-01

    NO2 is a key pollutant with highly variable concentrations in space and time. Quantitative information about its spatial variability at high resolution is currently scarce, but very valuable for (air quality) studies at the urban scale. APEX is a pushbroom hyperspectral imager with high spatial (60 by 80 m2) and spectral (2.8-3.3 nm) resolution. APEX flights were conducted over (1) the city and port of Antwerp, Belgium on April 14, 2015 and July 19, 2016, (2) Brussels, Belgium on June 30, 2015 (BUMBA project), and (3) Berlin, Germany on April 21, 2016 (AROMAT and AROMAPEX projects). APEX was operated from a DLR DO-228 plane at 6.1 km altitude. Over Berlin, two additional imagers, AirMAP (IUP Bremen) and SWING (BIRA-IASB), were simultaneously operated from a FUB Cessna at 3 km for intercomparison purposes. NO2 vertical column densities (VCDs) are retrieved based on (1) the DOAS analysis of the observed spectra in the visible region (470 nm - 510 nm), and (2) air mass factor calculations with the RTM VLIDORT 2.6. Results show that APEX is suitable (1) to detect the fast varying spectral signatures of a trace gas like NO2 and (2) to identify small scale gradients in the NO2 field and to resolve individual emission sources. Main NOx sources in the Antwerp area are related to (petro)chemical industry, while traffic emissions are dominant in Brussels. Over Berlin, 2 large industrial NO2 plumes are detected by all three imaging systems, crossing the city from west to east. The NO2 VCD levels range between 0.2 and 3.5 x 1016 molec cm-2. The typical detection limit for the APEX instrument is around 1.7 to 2.2 x 1015 molec cm-2. Correlation coefficients of 0.85 and slopes close to unity are obtained when compared to coincident car mobile-DOAS measurements. The NO2 retrieval algorithm, campaign results, and ongoing research concerning the comparison of the VCDs with in-situ surface concentrations and a high resolution (25 m) air quality model, i.e. RIO-IFDM, will be discussed.

  2. Development and application of the microbial fate and transport module for the Agricultural Policy/Environmental eXtender (APEX) model

    Science.gov (United States)

    Hong, E.; Park, Y.; Muirhead, R.; Jeong, J.; Pachepsky, Y. A.

    2017-12-01

    Pathogenic microorganisms in recreational and irrigation waters remain the subject of concern. Water quality models are used to estimate microbial quality of water sources, to evaluate microbial contamination-related risks, to guide the microbial water quality monitoring, and to evaluate the effect of agricultural management on the microbial water quality. The Agricultural Policy/Environmental eXtender (APEX) is the watershed-scale water quality model that includes highly detailed representation of agricultural management. The APEX currently does not have microbial fate and transport simulation capabilities. The objective of this work was to develop the first APEX microbial fate and transport module that could use the APEX conceptual model of manure removal together with recently introduced conceptualizations of the in-stream microbial fate and transport. The module utilizes manure erosion rates found in the APEX. Bacteria survival in soil-manure mixing layer was simulated with the two-stage survival model. Individual survival patterns were simulated for each manure application date. Simulated in-stream microbial fate and transport processes included the reach-scale passive release of bacteria with resuspended bottom sediment during high flow events, the transport of bacteria from bottom sediment due to the hyporheic exchange during low flow periods, the deposition with settling sediment, and the two-stage survival. Default parameter values were available from recently published databases. The APEX model with the newly developed microbial fate and transport module was applied to simulate seven years of monitoring data for the Toenepi watershed in New Zealand. Based on calibration and testing results, the APEX with the microbe module reproduced well the monitored pattern of E. coli concentrations at the watershed outlet. The APEX with the microbial fate and transport module will be utilized for predicting microbial quality of water under various agricultural

  3. Study of early laser-induced plasma dynamics: Transient electron density gradients via Thomson scattering and Stark Broadening, and the implications on laser-induced breakdown spectroscopy measurements

    International Nuclear Information System (INIS)

    Diwakar, P.K.; Hahn, D.W.

    2008-01-01

    To further develop laser-induced breakdown spectroscopy (LIBS) as an analytical technique, it is necessary to better understand the fundamental processes and mechanisms taking place during the plasma evolution. This paper addresses the very early plasma dynamics (first 100 ns) using direct plasma imaging, light scattering, and transmission measurements from a synchronized 532-nm probe laser pulse. During the first 50 ns following breakdown, significant Thomson scattering was observed while the probe laser interacted with the laser-induced plasma. The Thomson scattering was observed to peak 15-25 ns following plasma initiation and then decay rapidly, thereby revealing the highly transient nature of the free electron density and plasma equilibrium immediately following breakdown. Such an intense free electron density gradient is suggestive of a non-equilibrium, free electron wave generated by the initial breakdown and growth processes. Additional probe beam transmission measurements and electron density measurements via Stark broadening of the 500.1-nm nitrogen ion line corroborate the Thomson scattering observations. In concert, the data support the finding of a highly transient plasma that deviates from local thermodynamic equilibrium (LTE) conditions during the first tens of nanoseconds of plasma lifetime. The implications of this early plasma transient behavior are discussed in the context of plasma-analyte interactions and the role on LIBS measurements

  4. Laser ablation inductively coupled plasma dynamic reaction cell mass spectrometry for the multi-element analysis of polymers

    Science.gov (United States)

    Resano, M.; García-Ruiz, E.; Vanhaecke, F.

    2005-11-01

    In this work, the potential of laser ablation-inductively coupled plasma-mass spectrometry for the fast analysis of polymers has been explored. Different real-life samples (polyethylene shopping bags, an acrylonitrile butadiene styrene material and various plastic bricks) as well as several reference materials (VDA 001 to 004, Cd in polyethylene) have been selected for the study. Two polyethylene reference materials (ERM-EC 680 and 681), for which a reference or indicative value for the most relevant metals is available, have proved their suitability as standards for calibration. Special attention has been paid to the difficulties expected for the determination of Cr at the μg g - 1 level in this kind of materials, due to the interference of ArC + ions on the most abundant isotopes of Cr. The use of ammonia as a reaction gas in a dynamic reaction cell is shown to alleviate this problem, resulting in a limit of detection of 0.15 μg g - 1 for this element, while limiting only modestly the possibilities of the technique for simultaneous multi-element analysis. In this regard, As is the analyte most seriously affected by the use of ammonia, and its determination has to be carried out in vented mode, at the expense of measuring time. In all cases studied, accurate results could be obtained for elements ranging in content from the sub-μg g - 1 level to tens of thousands of μg g - 1 . However, the use of an element of known concentration as internal standard may be needed for materials with a matrix significantly different from that of the standard (polyethylene in this work). Precision ranged between 5% and 10% RSD for elements found at the 10 μg g - 1 level or higher, while this value could deteriorate to 20% for analytes found at the sub-μg g - 1 level. Overall, the technique evaluated presents many advantages for the fast and accurate multi-element analysis of these materials, avoiding laborious digestion procedures and minimizing the risk of analyte losses due

  5. Measuring molecular abundances in comet C/2014 Q2 (Lovejoy) using the APEX telescope

    Science.gov (United States)

    de Val-Borro, M.; Milam, S. N.; Cordiner, M. A.; Charnley, S. B.; Coulson, I. M.; Remijan, A. J.; Villanueva, G. L.

    2018-02-01

    Comet composition provides critical information on the chemical and physical processes that took place during the formation of the Solar system. We report here on millimetre spectroscopic observations of the long-period bright comet C/2014 Q2 (Lovejoy) using the Atacama Pathfinder Experiment (APEX) band 1 receiver between 2015 January UT 16.948 and 18.120, when the comet was at heliocentric distance of 1.30 au and geocentric distance of 0.53 au. Bright comets allow for sensitive observations of gaseous volatiles that sublimate in their coma. These observations allowed us to detect HCN, CH3OH (multiple transitions), H2CO and CO, and to measure precise molecular production rates. Additionally, sensitive upper limits were derived on the complex molecules acetaldehyde (CH3CHO) and formamide (NH2CHO) based on the average of the strongest lines in the targeted spectral range to improve the signal-to-noise ratio. Gas production rates are derived using a non-LTE molecular excitation calculation involving collisions with H2O and radiative pumping that becomes important in the outer coma due to solar radiation. We find a depletion of CO in C/2014 Q2 (Lovejoy) with a production rate relative to water of 2.0 per cent, and relatively low abundances of Q(HCN)/Q(H2O), 0.1 per cent, and Q(H2CO)/Q(H2O), 0.2 per cent. In contrast, the CH3OH relative abundance Q(CH3OH)/Q(H2O), 2.2 per cent, is close to the mean value observed in other comets. The measured production rates are consistent with values derived for this object from other facilities at similar wavelengths taking into account the difference in the fields of view. Based on the observed mixing ratios of organic molecules in four bright comets including C/2014 Q2, we find some support for atom addition reactions on cold dust being the origin of some of the molecules.

  6. Geochemical Characterization Of Cherts From The 3.46Ga Apex Basalt To Assess The Origins Of Possible Biosignatures

    Science.gov (United States)

    Bower, D. M.; Steele, A.; Ackerson, M. R.; Bullock, E. S.; Green, O. R.; Fries, M.; Conrad, P. G.

    2017-12-01

    Many terrestrial cherts contain compelling microtextures and mineral phases that are indicative of ancient life in hydrothermal systems on early Earth. In volcanically-derived hydrothermal deposits, cherts have undergone multiple alteration events often resulting in separate generations of quartz veins that are much younger than the host rocks. In some cases, multiple episodes of hydrothermal alteration obscure otherwise syngenetic biosignatures and likewise create false signatures in the form of secondary carbon emplacement or diagenetic phase changes. To better identify possible biosignatures in hydrothermal deposits and understand their origins, we used confocal micro Raman spectroscopy, electron probe microanalysis, and cathodoluminescence (CL) imaging to characterize the quartz fabrics, mineral phases, trace elements, and macromolecular carbon (MMC) in quartz veins from the 3.46 Ga Apex Basalt chert samples. MMC, anatase (TiO2), pyrite (Fe2S), jarosite-alunite (KFe3(SO4)2(OH)6 - Kal3(SO4)2(OH)6), chamosite-phyllosilicates, and Fe-oxides all occur in close association in multiple generations of quartz veins throughout the sample suite. Mineral phases xenotime (YPO4), scorodite (FeAsO4 . H2O), apatite (CaPO4), pentlandite ((Fe,Ni)9S8), barite (BaSO4), sphalerite ((Zn,Fe)S), dolomite ((CaMg(CO3)2) and halides occur in specific generations of quartz. Trace elements (Cr, Mn, Mo, Cu, Sc, Va, Sb, and Co) are heterogeneously distributed within individual samples and likely occur due to fluid scavenging of the host basalts. CL imaging of quartz demonstrates that the majority of silicate material in the Apex cherts underwent recrystallization. This could result in the alteration of MMC and associated mineral assemblages. The biogencity and true origins of morphological features and chemical signatures in the Apex cherts are hotly debated, yet discovering the causes and nature of these puzzling attributes will be key for determining the usefulness of interrogating

  7. Demonstration of a longitudinal concentration gradient along scala tympani by sequential sampling of perilymph from the cochlear apex.

    Science.gov (United States)

    Mynatt, Robert; Hale, Shane A; Gill, Ruth M; Plontke, Stefan K; Salt, Alec N

    2006-06-01

    Local applications of drugs to the inner ear are increasingly being used to treat patients' inner ear disorders. Knowledge of the pharmacokinetics of drugs in the inner ear fluids is essential for a scientific basis for such treatments. When auditory function is of primary interest, the drug's kinetics in scala tympani (ST) must be established. Measurement of drug levels in ST is technically difficult because of the known contamination of perilymph samples taken from the basal cochlear turn with cerebrospinal fluid (CSF). Recently, we reported a technique in which perilymph was sampled from the cochlear apex to minimize the influence of CSF contamination (J. Neurosci. Methods, doi: 10.1016/j.jneumeth.2005.10.008 ). This technique has now been extended by taking smaller fluid samples sequentially from the cochlear apex, which can be used to quantify drug gradients along ST. The sampling and analysis methods were evaluated using an ionic marker, trimethylphenylammonium (TMPA), that was applied to the round window membrane. After loading perilymph with TMPA, 10 1-muL samples were taken from the cochlear apex. The TMPA content of the samples was consistent with the first sample containing perilymph from apical regions and the fourth or fifth sample containing perilymph from the basal turn. TMPA concentration decreased in subsequent samples, as they increasingly contained CSF that had passed through ST. Sample concentration curves were interpreted quantitatively by simulation of the experiment with a finite element model and by an automated curve-fitting method by which the apical-basal gradient was estimated. The study demonstrates that sequential apical sampling provides drug gradient data for ST perilymph while avoiding the major distortions of sample composition associated with basal turn sampling. The method can be used for any substance for which a sensitive assay is available and is therefore of high relevance for the development of preclinical and clinical

  8. Ontogeny of head and caudal fin shape of an apex marine predator: The tiger shark (Galeocerdo cuvier).

    Science.gov (United States)

    Fu, Amy L; Hammerschlag, Neil; Lauder, George V; Wilga, Cheryl D; Kuo, Chi-Yun; Irschick, Duncan J

    2016-05-01

    How morphology changes with size can have profound effects on the life history and ecology of an animal. For apex predators that can impact higher level ecosystem processes, such changes may have consequences for other species. Tiger sharks (Galeocerdo cuvier) are an apex predator in tropical seas, and, as adults, are highly migratory. However, little is known about ontogenetic changes in their body form, especially in relation to two aspects of shape that influence locomotion (caudal fin) and feeding (head shape). We captured digital images of the heads and caudal fins of live tiger sharks from Southern Florida and the Bahamas ranging in body size (hence age), and quantified shape of each using elliptical Fourier analysis. This revealed changes in the shape of the head and caudal fin of tiger sharks across ontogeny. Smaller juvenile tiger sharks show an asymmetrical tail with the dorsal (upper) lobe being substantially larger than the ventral (lower) lobe, and transition to more symmetrical tail in larger adults, although the upper lobe remains relatively larger in adults. The heads of juvenile tiger sharks are more conical, which transition to relatively broader heads over ontogeny. We interpret these changes as a result of two ecological transitions. First, adult tiger sharks can undertake extensive migrations and a more symmetrical tail could be more efficient for swimming longer distances, although we did not test this possibility. Second, adult tiger sharks expand their diet to consume larger and more diverse prey with age (turtles, mammals, and elasmobranchs), which requires substantially greater bite area and force to process. In contrast, juvenile tiger sharks consume smaller prey, such as fishes, crustaceans, and invertebrates. Our data reveal significant morphological shifts in an apex predator, which could have effects for other species that tiger sharks consume and interact with. © 2016 Wiley Periodicals, Inc.

  9. Body-size trends of the extinct giant shark Carcharocles megalodon: a deep-time perspective on marine apex predators.

    Science.gov (United States)

    Pimiento, Catalina; Balk, Meghan A

    2015-06-01

    The extinct shark Carcharocles megalodon is one of the largest marine apex predators ever to exist. Nonetheless, little is known about its body-size variations through time and space. Here, we studied the body-size trends of C. megalodon through its temporal and geographic range to better understand its ecology and evolution. Given that this species was the last of the megatooth lineage, a group of species that shows a purported size increase through time, we hypothesized that C. megalodon also displayed this trend, increasing in size over time and reaching its largest size prior to extinction. We found that C. megalodon body-size distribution was left-skewed (suggesting a long-term selective pressure favoring larger individuals), and presented significant geographic variation (possibly as a result of the heterogeneous ecological constraints of this cosmopolitan species) over geologic time. Finally, we found that stasis was the general mode of size evolution of C. megalodon (i.e., no net changes over time), contrasting with the trends of the megatooth lineage and our hypothesis. Given that C. megalodon is a relatively long-lived species with a widely distributed fossil record, we further used this study system to provide a deep-time perspective to the understanding of the body-size trends of marine apex predators. For instance, our results suggest that (1) a selective pressure in predatory sharks for consuming a broader range of prey may favor larger individuals and produce left-skewed distributions on a geologic time scale; (2) body-size variations in cosmopolitan apex marine predators may depend on their interactions with geographically discrete communities; and (3) the inherent characteristics of shark species can produce stable sizes over geologic time, regardless of the size trends of their lineages.

  10. Analysis of cervical kyphosis and spinal balance in young idiopathic scoliosis patients classified by the apex of thoracic kyphosis.

    Science.gov (United States)

    Ito, Kenyu; Imagama, Shiro; Ito, Zenya; Ando, Kei; Kobayashi, Kazuyoshi; Hida, Tetsuro; Tsushima, Mikito; Ishikawa, Yoshimoto; Matsumoto, Akiyuki; Nishida, Yoshihiro; Ishiguro, Naoki

    2016-10-01

    Sagittal balance has recently been the focus of studies aimed at understanding the correction force required for both coronal and sagittal malalignment. However, the correlation between cervical kyphosis and sagittal balance in AIS patients has yet to be thoroughly investigated. This study aimed to clarify the correlation between cervical alignment and spinal balance in patients with adolescent idiopathic scoliosis (AIS). Here, we hypothesized that cervical kyphosis patients can be classified into groups by the apex of thoracic kyphosis. This study included 92 AIS patients (84 females, 8 males; mean age, 15.1 years). Patients were divided into the cervical lordosis (CL), cervical sigmoid (CS), or cervical kyphosis (CK) groups and further classified according to the apex of thoracic kyphosis into High (above T3), Middle (T4-T9), and Low (below T10) groups. There were 17 (18.5 %), 22 (23.9 %), and 53 (57.6 %) patients with CL, CS, and CK, respectively. In the CK group, 13 had CK-High, 35 had CK-Middle, and 5 had CK-Low. The C7 sagittal vertical axis (C7SVA) measurements were most backward in CK-High and most forward in CK-Low. The T5-12 kyphosis (TK) measurement was significantly lower in CK-High. Most AIS patients had kyphotic cervical alignment. Patients with CK can be classified as having CK-High, CK-Middle, or CK-Low according to the apex of thoracic kyphosis. CK-High is due to thoracic hypokyphosis with a backward balanced C7SVA. CK-Middle is well-balanced cervical kyphosis. CK-Low has forward-bent global kyphosis of the cervicothoracic spine that positioned the C7SVA forward.

  11. Sunyaev-Zel'Dovich effect observations of the bullet cluster (1E 0657-56) with APEX-SZ

    Energy Technology Data Exchange (ETDEWEB)

    Halverson, N.W.; Lanting, T.; Ade, P.A.R.; Basu, K.; Bender, A.N.; Benson, B.A.; Bertoldi, F.; Cho, H.-M.; Chon, G.; Clarke, J.; Dobbs, M.; Ferrusca, D.; Gusten, R.; Holzapfel, W.L.; Kovacs, A.; Kennedy, J.; Kermish, Z.; Kneissl, R.; Lee, A.T.; Lueker, M.; Mehl, J.; Menten, K.M.; Muders, D.; Nord, M.; Pacaud, F.; Plagge, T.; Reichardt, C.; Richards, P.L.; Schaaf, R.; Schilke, P.; Schuller, F.; Schwan, D.; Spieler, H.; Tucker, C.; Weiss, A.; Zahn, O.

    2008-07-25

    We present observations of the Sunyaev-Zel'dovich effect (SZE) in the Bullet cluster (1E 0657-56) using the APEX-SZ instrument at 150 GHz with a resolution of 1'. The main results are maps of the SZE in this massive, merging galaxy cluster. The cluster is detected with 23 sigma significance within the central 1' radius of the source position. The SZE map has a broadly similar morphology to that in existing X-ray maps of this system, and we find no evidence for significant contamination of the SZE emission by radio or IR sources. In order to make simple quantitative comparisons with cluster gas models derived from X-ray observations, we fit our data to an isothermal elliptical beta model, despite the inadequacy of such a model for this complex merging system. With an X-ray derived prior on the power-law index, beta = 1.04+0.16-0.10, we find a core radius rc = 142" +- 18", an axial ratio of 0.889 +- 0.072, and a central temperature decrement of -771 +- 71 muKCMB, including a +-5.5percent flux calibration uncertainty. Combining the APEX-SZ map with a map of projected electron surface density from Chandra X-ray observations, we determine the mass-weighted temperature of the cluster gas to be Tmg = 10.8 +- 0.9 keV, significantly lower than some previously reported X-ray spectroscopic temperatures. Under the assumption of an isothermal cluster gas distribution in hydrostatic equilibrium, we compute the gas mass fraction for prolate and oblate spheroidal geometries and find it to be consistent with previous results from X-ray and weak-lensing observations. This work is the first result from the APEX-SZ experiment and represents the first reported scientific result from observations with a large array of multiplexed superconducting transition-edge sensor bolometers.

  12. Analysis of Surgical Freedom Variation Across the Basilar Artery Bifurcation: Towards a Deeper Insight Into Approach Selection for Basilar Apex Aneurysms.

    Science.gov (United States)

    Tayebi Meybodi, Ali; Benet, Arnau; Rodriguez Rubio, Roberto; Yousef, Sonia; Lawton, Michael T

    2018-03-03

    The orbitozygomatic approach is generally advocated over the pterional approach for basilar apex aneurysms. However, the impact of the extensions of the pterional approach on the obtained maneuverability over multiple vascular targets (relevant to basilar apex surgery) has not been studied before. To analyze the patterns of surgical freedom change across the basilar bifurcation between the pterional, orbitopterional, and orbitozygomatic approaches. Surgical freedom was assessed for 3 vascular targets important in basilar apex aneurysm surgery (ipsilateral and contralateral P1-P2 junctions, and basilar apex), and compared between the pterional, orbitopterional, and orbitozygomatic approaches in 10 cadaveric specimens. Transitioning from the pterional to orbitopterional approach, the surgical freedom increased significantly at all 3 targets (P < .05). However, the gain in surgical freedom declined progressively from the most superficial target (60% for ipsilateral P1-P2 junction) to the deepest target (35% for contralateral P1-P2 junction). Conversely, transitioning from the orbitopterional to the orbitozygomatic approach, the gain in surgical freedom was minimal for the ipsilateral P1-P2 and basilar apex (<4%), but increased dramatically to 19% at the contralateral P1-P2 junction. The orbitopterional approach provides a remarkable increase in surgical maneuverability compared to the pterional approach for the basilar apex target and the relevant adjacent arterial targets. However, compared to the orbitopterional, the orbitozygomatic approach adds little maneuverability except for the deepest target (ie, contralateral P1-P2 junction). Therefore, the orbitozygomatic approach may be most efficacious with larger basilar apex aneurysms limiting the control over of the contralateral P1 PCA.

  13. Effect of right ventricular electrode location (outflow tract vs. apex) on mechanical Ventricular synchrony in patients that underwent pacemaker implant therapy

    International Nuclear Information System (INIS)

    Rincon, Oscar S; Saenz, Luis C; Salazar, Gabriel; Hernandez, Edgar

    2008-01-01

    Objective: to assess in depth the effect of ventricular stimulation from the right ventricular outflow tract and the apex on mechanical ventricular synchrony. Materials And Methods: cohort analytical study. 20 patients with indication of definitive pacemaker indication underwent trans thoracic echocardiogram before and after pacemaker implant with electrode implantation in the right ventricular outflow tract and in the apex (10 patients in each group). There was no structural cardiopathy, ejection fraction was ? 50%, QRS and AV conduction were normal. Mechanical ventricular asynchrony (M mode and tissue doppler) and implant and device parameters were evaluated. Statistical Analysis: results are given as mean values, standard deviation or percentages.Continuous variables were compared using Chi-square test and ANOVA. A p <0.05 value was considered statistically significant. Results: in five patients (25%) a pre-implant ventricular asynchrony was found; in seven (70%) ventricular asynchrony post-implant in the right ventricle outflow tract and in 5 (50%) in the apex. Mean interventricular pot-implant delay was 21,6 ms in the right ventricular outflow tract and 11,5 ms in the apex (p = 0,8); mean septal to lateral wall delay was 73 ms in the right ventricular outflow tract and 26 ms in the apex (p = 0,8). QRS post-implant delay was 134 ms in the right ventricular outflow tract and 140 ms in the apex (p = 0,1). No differences between implant parameters and device programming were found. Conclusions: presence of ventricular asynchrony was evidenced in patients with normal QRS and structurally healthy heart. Ventricular stimulation with pacemaker from the apex or the right ventricular outflow tract suggests acute ventricular asynchrony at least in 60% of the cases, without statistically significant difference between both groups.

  14. Comparison of two label-free global quantitation methods, APEX and 2D gel electrophoresis, applied to the Shigella dysenteriae proteome

    Directory of Open Access Journals (Sweden)

    Fleischmann Robert D

    2009-06-01

    Full Text Available Abstract The in vitro stationary phase proteome of the human pathogen Shigella dysenteriae serotype 1 (SD1 was quantitatively analyzed in Coomassie Blue G250 (CBB-stained 2D gels. More than four hundred and fifty proteins, of which 271 were associated with distinct gel spots, were identified. In parallel, we employed 2D-LC-MS/MS followed by the label-free computationally modified spectral counting method APEX for absolute protein expression measurements. Of the 4502 genome-predicted SD1 proteins, 1148 proteins were identified with a false positive discovery rate of 5% and quantitated using 2D-LC-MS/MS and APEX. The dynamic range of the APEX method was approximately one order of magnitude higher than that of CBB-stained spot intensity quantitation. A squared Pearson correlation analysis revealed a reasonably good correlation (R2 = 0.67 for protein quantities surveyed by both methods. The correlation was decreased for protein subsets with specific physicochemical properties, such as low Mr values and high hydropathy scores. Stoichiometric ratios of subunits of protein complexes characterized in E. coli were compared with APEX quantitative ratios of orthologous SD1 protein complexes. A high correlation was observed for subunits of soluble cellular protein complexes in several cases, demonstrating versatile applications of the APEX method in quantitative proteomics.

  15. Auroral-zone plasma dynamics

    International Nuclear Information System (INIS)

    Gorney, D.J.

    1982-01-01

    Analysis of the USAF S3-3 charged particle data and electric field observations has provided extensive quantitative understanding of the auroral particle acceleration process. The results of an effort to use energetic charged particle observations to probe the altitude profile of auroral electric potential structures by applying adiabatic mapping theory are presented here. In situ energetic charged particle measurements differ from local electric field observations in that charged particles execute dynamic trajectories along the magnetic field lines and retain information on the spatial electric potential distribution in their velocity space distribution function. Although a unique determination of the potential distribution is not possible, basic differences between local or non-local acceleration are readily apparent in the particle observations. Together, the charged particle and electric field measurements have enabled us to form a reasonable picture of the auroral ''inverted-V'' structure which can then be applied to study the nonadiabatic processes that occur in these strong acceleration regions, such as energy scattering of ion and electron beams. Specifically, this study shows that a large scale auroral electric field exists at all times in the evening sector with an altitude distribution that is fairly unstructured at altitudes near and above one earth radius. Significant parallel potential drop is not observed below about 4000 kilometers altitude. At times, however, a substantial portion of the potential drop appears to lie in the low altitude region (4000-10,000 km)

  16. Pre-equilibrium plasma dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Heinz, U.

    1986-01-01

    Approaches towards understanding and describing the pre-equilibrium stage of quark-gluon plasma formation in heavy-ion collisions are reviewed. Focus is on a kinetic theory approach to non-equilibrium dynamics, its extension to include the dynamics of color degrees of freedom when applied to the quark-gluon plasma, its quantum field theoretical foundations, and its relationship to both the particle formation stage at the very beginning of the nuclear collision and the hydrodynamic stage at late collision times. The usefulness of this approach to obtain the transport coefficients in the quark-gluon plasma and to derive the collective mode spectrum and damping rates in this phase are discussed. Comments are made on the general difficulty to find appropriated initial conditions to get the kinetic theory started, and a specific model is given that demonstrates that, once given such initial conditions, the system can be followed all the way through into the hydrodynamical regime. 39 refs., 7 figs. (LEW)

  17. Pre-equilibrium plasma dynamics

    International Nuclear Information System (INIS)

    Heinz, U.

    1986-01-01

    Approaches towards understanding and describing the pre-equilibrium stage of quark-gluon plasma formation in heavy-ion collisions are reviewed. Focus is on a kinetic theory approach to non-equilibrium dynamics, its extension to include the dynamics of color degrees of freedom when applied to the quark-gluon plasma, its quantum field theoretical foundations, and its relationship to both the particle formation stage at the very beginning of the nuclear collision and the hydrodynamic stage at late collision times. The usefulness of this approach to obtain the transport coefficients in the quark-gluon plasma and to derive the collective mode spectrum and damping rates in this phase are discussed. Comments are made on the general difficulty to find appropriated initial conditions to get the kinetic theory started, and a specific model is given that demonstrates that, once given such initial conditions, the system can be followed all the way through into the hydrodynamical regime. 39 refs., 7 figs

  18. Selective Deactivation of Gibberellins below the Shoot Apex is Critical to Flowering but Not to Stem Elongation of Lolium

    DEFF Research Database (Denmark)

    King, Rod W; Mander, Lewis N; Asp, Torben

    2008-01-01

    in their effectiveness for flowering because they are deactivated by C-2 hydroxylation below the shoot apex. In contrast, GA5 is effective because of its structural protection at C-2. Excised vegetative shoot tips rapidly degrade [14C]GA1, [14C]GA4, and [14C]GA20 (>80% in 6 h), but not [14C]GA5. Coincidentally, genes...... encoding two 2β-oxidases and a putative 16-17-epoxidase were most expressed just below the shoot apex (4 mm), expression of these GA deactivation genes is reduced, so allowing GA1 and GA4 to promote sub-apical stem elongation. Subsequently, GA degradation declines...... in florally induced shoot tips and these GAs can become active for floral development. Structural changes which stabilize GA4 confirm the link between florigenicity and restricted GA 2β-hydroxylation (e.g. 2 -hydroxylation and C-2 di-methylation). Additionally, a 2-oxidase inhibitor (Trinexapac Ethyl...

  19. Effects on auditory-nerve fibers of opening the otic capsule at the apex of the chinchilla cochlea

    Science.gov (United States)

    Recio-Spinoso, Alberto; Temchin, Andrei N.; Ruggero, Mario A.

    2015-12-01

    Vibration responses to clicks measured at the apex of chinchilla cochleae with open otic capsules have onsets much shorter than those of responses of auditory-nerve fibers (ANFs) corrected for synaptic and neural delays. Apical vibration responses to tones in open cochleae also differ in other respects from the responses to tones of ANFs with low characteristic frequency (CF) in normal chinchilla cochleae. To further specify the origin(s) of these differences, we recorded from chinchilla ANFs after delicately opening a small hole in the otic capsule overlying scala vestibuli in the cochlear apex. In those cochleae, the earliest ANF responses to clicks are often evoked by condensation (rather than rarefaction) clicks and responses to tones often exhibit level-dependent phase changes different from those in normal cochleae. These findings are largely consistent with, and seem to account for, apical vibration responses of cochleae with open otic capsules. An unexpected finding is that the tuning curves of ANFs with moderately high CF and normal CF thresholds often had hypersensitive tails.

  20. Simple landmark for preservation of the cochlea during maximum drilling of the petrous apex through the anterior transpetrosal approach

    International Nuclear Information System (INIS)

    Seo, Yoshinobu; Sasaki, Takehiko; Nakamura, Hirohiko

    2010-01-01

    The cochlea is one of the most important organs to preserve during skull base surgery. However, no definite landmark for the cochlea has been identified during maximum drilling of the petrous apex such as anterior transpetrosal approach. The relationship between the cochlea and the petrous portion of the internal carotid artery (ICA) was assessed with computed tomography (CT) in 70 petrous bones of 35 patients, 16 males and 19 females aged 12-85 years (mean 48.6 years). After accumulation of volume data with multidetector CT, axial bone window images of 1-mm thickness were obtained to identify the cochlea and the horizontal petrous portion of the ICA. The distance was measured between the extended line of the posteromedial side of the horizontal petrous portion of the ICA and the basal turn of the cochlea. If the cochlea was located posteromedial to the ICA, the distance was expressed as a positive number, but if anterolateral, as a negative number. The mean distance was 0.6 mm (range -4.9 to 3.9 mm) and had no significant correlation with sex or age. The cochlea varies in location compared with the horizontal petrous portion of the ICA. Measurement of the depth and distance between the extended line of the posteromedial side of the horizontal intrapetrous ICA and the cochlea before surgery will save time, increase safety, and maximize bone evacuation during drilling of the petrous apex. (author)

  1. The application of APEX images in the assessment of the state of non-forest vegetation in the Karkonosze Mountains

    Directory of Open Access Journals (Sweden)

    Jarocińska Anna M.

    2016-03-01

    Full Text Available Information about vegetation condition is needed for the effective management of natural resources and the estimation of the effectiveness of nature conservation. The aim of the study was to analyse the condition of non-forest mountain communities: synanthropic communities and natural grasslands. UNESCO’s M&B Karkonosze Transboundary Biosphere Reserve was selected as the research area. The analysis was based on 40 field test polygons and APEX hyperspectral images. The field measurements allowed the collection of biophysical parameters - Leaf Area Index (LAI, fraction of Absorbed Photosynthetically Active Radiation (fAPAR and chlorophyll content - which were correlated with vegetation indices calculated using the APEX images. Correlations were observed between the vegetation indices (general condition, plant structure and total area of leaves (LAI, as well as fraction of Absorbed Photosynthetically Active Radiation (fAPAR. The outcomes show that the non-forest communities in the Karkonosze are in good condition, with the synanthropic communities characterised by better condition compared to the natural communities.

  2. Motion of organ of Corti structures in the gerbil cochlear apex, measured with a commercial optical coherence tomography (OCT) system

    Science.gov (United States)

    Ravicz, Michael E.; Cho, Nam-Hyun; Maftoon, Nima; Puria, Sunil

    2018-05-01

    Recent developments in Optical Coherence Tomography (OCT) allow measurements of cochlear motions through the bony cochlear wall without holes at spatial resolutions approaching about 10 µm. Measurements to date have been made with custom OCT systems with long development times. We present measurements made with a commercial OCT system driven by custom software (VibOCT) that facilitates near real-time frequency response measurements. The 905-nm wavelength laser and high-speed (100 kHz) camera provide higher axial resolution (3 µm in air) and temporal resolution than previous studies and a sub-nanometer noise floor in air. We gathered anatomical images of the gerbil cochlear apex in vivo at higher resolution than available previously, sufficient to resolve individual outer hair cells, pillar cells, tunnel of Corti and inner sulcus regions. Images from the 3rd apical turn show a bulging of Reissners membrane in vivo that flattened post-mortem with a concomitant reduction in the distance between the Henson cell border and the stria vascularis wall. Vibrometry of the organ of Corti shows a low-pass characteristic in-vivo and post-mortem with a traveling wave-like phase delay similar to a recent study rather than the sharp tuning seen more basally. This system can provide valuable information on cochlear function, which is also useful for the development of detailed cochlear models of the passive and active gerbil apex.

  3. Curve Modulation and Apex Migration Using Shilla Growth Guidance Rods for Early-onset Scoliosis at 5-Year Follow-up.

    Science.gov (United States)

    Wilkinson, John T; Songy, Chad E; Bumpass, David B; McCullough, Francis L; McCarthy, Richard E

    2017-04-03

    The Shilla procedure was designed to correct and control early-onset spinal deformity while harnessing a child's remaining spinal growth. It allows for controlled axial skeletal growth within the construct, avoiding the need for frequent surgeries to lengthen implants. We hypothesized that curve characteristics evolve over time after initial apex fusion and placement of the Shilla implants. The purpose of this study was to identify trends in curve evolution after Shilla implantation and understand how these changes influence ultimate outcome. A single-center, retrospective review of all patients with Shilla implants in place for ≥5 years yielded 21 patients. Charts and radiographs were reviewed to compare coronal curve characteristics preoperatively, postoperatively, and at last follow-up to note changes in the apex of the primary curve. Also noted were the development of adjacent compensatory curves, the overall vertical spinal growth, and the need for definitive spinal fusion once skeletal maturity was reached. Of the 21 patients, the curve apex migrated caudally in 12 patients (57%) and cephalad in 1 patient (5%), with a mean migration of 2.7 vertebral levels. Two patients (10%) developed new, significant compensatory curves (1 caudal and 1 cephalad). All patients demonstrated spinal growth in T1-S1 length following index surgery (mean, 45 mm). At skeletal maturity, 10 patients underwent definitive posterior spinal fusion and instrumentation, and 3 underwent implant removal alone. This study constitutes the longest follow-up of Shilla patients evaluating curve and implant behavior. Results of this review suggest that the apex of the fused primary curve shifts in approximately 62% of patients, with nearly all of these (92%) involving a distal migration. Compensatory curves did develop after Shilla placement as well. Overall, these findings represent adding-on distal to the apex after Shilla instrumentation rather than a crankshaft phenomenon about the apex. A

  4. Plasma dynamic synthesis and obtaining ultrafine powders of iron oxides with high content of ε-Fe{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Sivkov, Alexander [Institute of Power Engineering, National Research Tomsk Polytechnic University, Lenin av., 30, Tomsk 634050 (Russian Federation); Naiden, Evgenii [Faculty of Radiophysics, National Research Tomsk State University, Lenin av., 36, Tomsk 634050 (Russian Federation); Ivashutenko, Alexander [Institute of Power Engineering, National Research Tomsk Polytechnic University, Lenin av., 30, Tomsk 634050 (Russian Federation); Shanenkov, Ivan, E-mail: Swordi@list.ru [Institute of Power Engineering, National Research Tomsk Polytechnic University, Lenin av., 30, Tomsk 634050 (Russian Federation)

    2016-05-01

    The ultrafine iron oxide powders were successfully synthesized using the plasma dynamic synthesis method, based on the use of a coaxial magnetoplasma accelerator with the iron electrode system. The synthesis was implemented in the high-speed iron-containing plasma jet, flowing into the space of the sealed chamber, filled with the gaseous mixture of oxygen and argon at different ratios. The XRD investigations showed that the synthesized products were heterophase and consisted of three main phases such as magnetite Fe{sub 3}O{sub 4}, hematite α-Fe{sub 2}O{sub 3} and ε-Fe{sub 2}O{sub 3}. The SEM data confirmed the presence of three particle types: the hollow spheroids with sizes about hundreds of micrometers (magnetite), the particles with sizes up to 100 μm from the porous material of sintered submicron particles (hematite), and nanoscale particles (ε-phase). We found that at the higher oxygen concentration the content of ε-Fe{sub 2}O{sub 3} is increased up to ~50% at the same time with decreasing the Fe{sub 3}O{sub 4} phase. The magnetic properties of the products are mainly determined by magnetite characteristics and are significantly reduced with decreasing its content in the powder. In order to investigate the synthesized ε-Fe{sub 2}O{sub 3} on the ability to absorb the electromagnetic radiation in the millimeter wavelength range, we separated the product with the higher ε-phase concentration. The fraction mainly, consisting of ε-Fe{sub 2}O{sub 3}, showed the occurrence of the natural resonance at frequencies of 8.3 GHz and 130 GHz. - Highlights: • We synthesized iron oxide powder with high content of ε-Fe{sub 2}O{sub 3}. • Synthesis is implemented using iron-containing plasma jet flowing into O{sub 2} atm. • Synthesized powders are heterophase and consist of ε-Fe{sub 2}O{sub 3,} α-Fe{sub 2}O{sub 3} and Fe{sub 3}O{sub 4}. • ε-Fe{sub 2}O{sub 3} content increases up to 50% with increasing the O{sub 2} volume concentration. • We found the

  5. Development and evaluation of the microbial fate and transport module for the Agricultural Policy/Environmental eXtender (APEX) model

    Science.gov (United States)

    Hong, Eun-Mi; Park, Yongeun; Muirhead, Richard; Pachepsky, Yakov

    2017-04-01

    Pathogenic microorganisms in recreational and irrigation waters remain the subject of concern. Water quality models are used to estimate microbial quality of water sources, to evaluate microbial contamination-related risks, to guide the microbial water quality monitoring, and to evaluate the effect of agricultural management on the microbial water quality. The Agricultural Policy/Environmental eXtender (APEX) is the watershed-scale water quality model that includes highly detailed representation of agricultural management. The APEX currently does not have microbial fate and transport simulation capabilities. The objective of this work was to develop the first APEX microbial fate and transport module that could use the APEX conceptual model of manure removal together with recently introduced conceptualizations of the in-stream microbial fate and transport. The module utilizes manure erosion rates found in the APEX. The total number of removed bacteria was set to the concentrations of bacteria in soil-manure mixing layer and eroded manure amount. Bacteria survival in soil-manure mixing layer was simulated with the two-stage survival model. Individual survival patterns were simulated for each manure application date. Simulated in-stream microbial fate and transport processes included the reach-scale passive release of bacteria with resuspended bottom sediment during high flow events, the transport of bacteria from bottom sediment due to the hyporheic exchange during low flow periods, the deposition with settling sediment, and the two-stage survival. Default parameter values were available from recently published databases. The APEX model with the newly developed microbial fate and transport module was applied to simulate seven years of monitoring data for the Toenepi watershed in New Zealand. The stream network of the watershed ran through grazing lands with the daily bovine waste deposition. Based on calibration and testing results, the APEX with the microbe module

  6. Exploration Review

    Science.gov (United States)

    Wilburn, D.R.; Stanley, K.A.

    2013-01-01

    This summary of international mineral exploration activities for 2012 draws upon information from industry sources, published literature and U.S. Geological Survey (USGS) specialists. The summary provides data on exploration budgets by region and mineral commodity, identifies significant mineral discoveries and areas of mineral exploration, discusses government programs affecting the mineral exploration industry and presents analyses of exploration activities performed by the mineral industry. Three sources of information are reported and analyzed in this annual review of international exploration for 2012: 1) budgetary statistics expressed in U.S. nominal dollars provided by SNL Metals Economics Group (MEG) of Halifax, Nova Scotia; 2) regional and site-specific exploration activities that took place in 2012 as compiled by the USGS and 3) regional events including economic, social and political conditions that affected exploration activities, which were derived from published sources and unpublished discussions with USGS and industry specialists.

  7. Exploration technology

    Energy Technology Data Exchange (ETDEWEB)

    Roennevik, H.C. [Saga Petroleum A/S, Forus (Norway)

    1996-12-31

    The paper evaluates exploration technology. Topics discussed are: Visions; the subsurface challenge; the creative tension; the exploration process; seismic; geology; organic geochemistry; seismic resolution; integration; drilling; value creation. 4 refs., 22 figs.

  8. Repository exploration

    International Nuclear Information System (INIS)

    Pentz, D.L.

    1984-01-01

    This paper discusses exploration objectives and requirements for a nuclear repository in the U.S.A. The importance of designing the exploration program to meet the system performance objectives is emphasized and some examples of the extent of exploration required before the License Application for Construction Authorization is granted are also discussed

  9. Direct quantification of energy intake in an apex marine predator suggests physiology is a key driver of migrations.

    Science.gov (United States)

    Whitlock, Rebecca E; Hazen, Elliott L; Walli, Andreas; Farwell, Charles; Bograd, Steven J; Foley, David G; Castleton, Michael; Block, Barbara A

    2015-09-01

    Pacific bluefin tuna (Thunnus orientalis) are highly migratory apex marine predators that inhabit a broad thermal niche. The energy needed for migration must be garnered by foraging, but measuring energy intake in the marine environment is challenging. We quantified the energy intake of Pacific bluefin tuna in the California Current using a laboratory-validated model, the first such measurement in a wild marine predator. Mean daily energy intake was highest off the coast of Baja California, Mexico in summer (mean ± SD, 1034 ± 669 kcal), followed by autumn when Pacific bluefin achieve their northernmost range in waters off northern California (944 ± 579 kcal). Movements were not always consistent with maximizing energy intake: the Pacific bluefin move out of energy rich waters both in late summer and winter, coincident with rising and falling water temperatures, respectively. We hypothesize that temperature-related physiological constraints drive migration and that Pacific bluefin tuna optimize energy intake within a range of optimal aerobic performance.

  10. Plants regeneration of a papaya hybrid (IBP 42-99 from callus obtained from apexes of in vitro plants.

    Directory of Open Access Journals (Sweden)

    Jorge Gallardo Colina

    2004-07-01

    Full Text Available In Cuba there realizes innumerable efforts to increase the food production and especially the fruit trees Inside which the papaya has great importance. In this sense studies are realized to obtain plants resistant to virus that they need of tools that they support and increase the indexes of obtaining transgenic line in the events of transformation specifically in a papaya hybrid. As main objective was to develop a protocol for the regeneration of plants of papaya hybrid from callus obtained of in vitro plant apexes.plan to develop a tool that supports and increases the indexes of obtaining line transgenic in the events of transformation in a hybrid of papaya.In vitro plants of the hybrid IBP 42-99 were used as plant material. The culture medium Nitsh and Nitsh was used and the growth regulators that permitted the obtaining of the best callus with embryogenic structures were studied, and also, the concentrations in which they were more efficient were adjusted. The capacity of callus formation from different parts of the stem of the in vitro plants was studied. Different culture medium for the regeneration of papaya plants from the obtained callus was studied. It was possible to obtain callus by combining 6-BAP with ANA and AIA. The best results are obtained when segments from in vitro plants shoot, 1 cm length from the meristem, were used. Also, by eliminating the meristem in the apexes, an increase in the callus formation capacity of the explant was achieved. Plants were obtained from callus using the culture medium MS supplement with 0.09mg.l-1 of AIA, 0.01mg.l-1 of AG3 and 2mg.l-1 of Zeatin and the best percentage was achieved with the callus coming from the treatments with less concentration of 6-BAP and AIA. Key words: culture medium, micropropagation, organogenesis, segments

  11. Sensitivity Analysis of the Agricultural Policy/Environmental eXtender (APEX) for Phosphorus Loads in Tile-Drained Landscapes.

    Science.gov (United States)

    Ford, W; King, K; Williams, M; Williams, J; Fausey, N

    2015-07-01

    Numerical modeling is an economical and feasible approach for quantifying the effects of best management practices on dissolved reactive phosphorus (DRP) loadings from agricultural fields. However, tools that simulate both surface and subsurface DRP pathways are limited and have not been robustly evaluated in tile-drained landscapes. The objectives of this study were to test the ability of the Agricultural Policy/Environmental eXtender (APEX), a widely used field-scale model, to simulate surface and tile P loadings over management, hydrologic, biologic, tile, and soil gradients and to better understand the behavior of P delivery at the edge-of-field in tile-drained midwestern landscapes. To do this, a global, variance-based sensitivity analysis was performed, and model outputs were compared with measured P loads obtained from 14 surface and subsurface edge-of-field sites across central and northwestern Ohio. Results of the sensitivity analysis showed that response variables for DRP were highly sensitive to coupled interactions between presumed important parameters, suggesting nonlinearity of DRP delivery at the edge-of-field. Comparison of model results to edge-of-field data showcased the ability of APEX to simulate surface and subsurface runoff and the associated DRP loading at monthly to annual timescales; however, some high DRP concentrations and fluxes were not reflected in the model, suggesting the presence of preferential flow. Results from this study provide new insights into baseline tile DRP loadings that exceed thresholds for algal proliferation. Further, negative feedbacks between surface and subsurface DRP delivery suggest caution is needed when implementing DRP-based best management practices designed for a specific flow pathway. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. How far is the root apex of a unilateral impacted canine from the root apices' arch form?

    Science.gov (United States)

    Kim, Sung-Hun; Kim, You-Min; Oh, Sewoong; Kim, Seong-Sik; Park, Soo-Byung; Son, Woo-Sung; Kim, Yong-Il

    2017-02-01

    The purpose of this study was to determine the arch form of the root apices of normally erupting teeth and then determine the differences in the location of the apex of impacted canines relative to normally erupting canines. In addition, we sought to determine whether the labiopalatal position of the impacted canines influences the position of the apices. The study included 21 patients with unerupted canines that subsequently had a normal eruption, 21 patients with palatally impacted canines, 27 patients with labially impacted canines, and 17 patients with midalveolus impacted canines. Images were obtained using cone beam computed tomography, and the x, y, and z coordinates of the root apices were determined using Ondemand3D software (Cybermed Co., Seoul, Korea). Two-dimensional coordinates were converted from acquired 3-dimensional coordinates via projection on a palatal plane, and the Procrustes method was used to process the converted 2-dimensional coordinates and to draw the arch forms of the root apices. Finally, we measured the extent of root apex deviation from the arch forms of the root apices. Normally erupting canines showed that even though calcifications may be immature, their positions were aligned with a normal arch form. The root apices of the impacted canines were an average of 6.572 mm away from the root apices' arch form, whereas those of the contralateral nonimpacted canines were an average distance of 2.221 mm away, a statistically significant difference. The palatally impacted canines' root apices distribution tended toward the first premolar root apices. Incompletely calcified, unerupted teeth with a subsequent normal eruption showed a normal arch form of the root apices. The root apices of impacted canines were farther from the arch forms than were the nonimpacted canines. Also, the root apices of impacted canines in the palatal area showed distributions different from those of the other impacted canine groups. Copyright © 2017 American

  13. Lateral and vertical manipulations of single atoms on the Ag(1 1 1) surface with the copper single-atom and trimer-apex tips

    International Nuclear Information System (INIS)

    Xie Yiqun; Yang Tianxing; Ye Xiang; Huang Lei

    2011-01-01

    We study the lateral and vertical manipulations of single Ag and Cu atoms on the Ag(1 1 1) surface with the Cu single-atom and trimer-apex tips using molecular statics simulations. The reliability of the lateral manipulation with the Cu single-atom tip is investigated, and compared with that for the Ag tips. We find that overall the manipulation reliability (MR) increases with the decreasing tip height, and in a wide tip-height range the MR is better than those for both the Ag single-atom and trimer-apex tips. This is due to the stronger attractive force of the Cu tip and its better stability against the interactions with the Ag surface. With the Cu trimer-apex tip, the single Ag and Cu adatoms can be picked up from the flat Ag(1 1 1) surface, and moreover a reversible vertical manipulation of single Ag atoms on the stepped Ag(1 1 1) surface is possible, suggesting a method to modify two-dimensional Ag nanostructures on the Ag(1 1 1) surface with the Cu trimer-apex tip.

  14. Lateral manipulation of small clusters on the Cu and Ag(1 1 1) surfaces with the single-atom and trimer-apex tips: Reliability study

    International Nuclear Information System (INIS)

    Xie Yiqun; Liu Fen; Huang Lei

    2010-01-01

    We study the reliability of the lateral manipulation of small Cu clusters (dimer and trimer) on the flat Cu(1 1 1) surface with both the single-atom and trimer-apex tips and that for the Ag/Ag(1 1 1) system, and compare the results between the two systems as well as with the single-atom manipulation on these surfaces. Manipulations are simulated using molecular statics method with semi-empirical potentials. The dependence of the manipulation reliability on the tip height and tip orientation are investigated. Overall, the manipulation reliability increases with decreasing tip height although it depends obviously on the tip orientation. For the Cu/Cu(1 1 1) system, the manipulation of the dimmer and trimer can be successful with both tips. The manipulation reliability can be improved by the trimer-apex tip, and the tip-height range for the successful manipulation is also broader, as compared to the single-atom apex tip. Differently from the single-atom manipulation, the tip orientation has a noticeable influence on the manipulation reliability even for the single-atom tip due to the stronger tip-cluster and surface-adatom interactions in cluster manipulation. For the Ag/Ag(1 1 1) system, successful manipulations only be achieved with the trimer-apex tip, and the manipulation reliability is worse than that of the Cu/Cu(1 1 1) system, indicating the difference in mechanic properties between the two surfaces at the atomic level.

  15. Estimation of phosphorous loss from agricultural land in the Heartland region of the U.S.A. using the APEX model

    Science.gov (United States)

    Accurate phosphorus (P) loss estimation from agricultural land is important for development of best management practices and protection of water quality. The Agricultural Policy/Environmental Extender (APEX) model is a powerful simulation model designed to simulate edge-of-field water, sediment, an...

  16. Development and evaluation of the microbial fate and transport module for the Agricultural Policy/Environmental eXtender (APEX) model

    Science.gov (United States)

    Microbial contamination of waters in agricultural watershed is the critical public health issue. The watershed-scale model has been proven to be one of the candidate tools for predicting microbial water quality and evaluating management practices. The Agricultural Policy/Environmental eXtender (APEX...

  17. Estimation of phosphorus loss from agricultural land in the Heartland region using the APEX model: a first step to evaluating phosphorus indices

    Science.gov (United States)

    Purpose. Phosphorus (P) indices are a key tool to minimize P loss from agricultural fields but there is insufficient water quality data to fully test them. Our goal is to use the Agricultural Policy/Environmental eXtender Model (APEX), calibrated with existing edge-of-field runoff data, to refine P...

  18. APEX (Aqueous Photochemistry of Environmentally occurring Xenobiotics): a free software tool to predict the kinetics of photochemical processes in surface waters.

    Science.gov (United States)

    Bodrato, Marco; Vione, Davide

    2014-04-01

    The APEX software predicts the photochemical transformation kinetics of xenobiotics in surface waters as a function of: photoreactivity parameters (direct photolysis quantum yield and second-order reaction rate constants with transient species, namely ˙OH, CO₃(-)˙, (1)O₂ and the triplet states of chromophoric dissolved organic matter, (3)CDOM*), water chemistry (nitrate, nitrite, bicarbonate, carbonate, bromide and dissolved organic carbon, DOC), and water depth (more specifically, the optical path length of sunlight in water). It applies to well-mixed surface water layers, including the epilimnion of stratified lakes, and the output data are average values over the considered water column. Based on intermediate formation yields from the parent compound via the different photochemical pathways, the software can also predict intermediate formation kinetics and overall yield. APEX is based on a photochemical model that has been validated against available field data of pollutant phototransformation, with good agreement between model predictions and field results. The APEX software makes allowance for different levels of knowledge of a photochemical system. For instance, the absorption spectrum of surface water can be used if known, or otherwise it can be modelled from the values of DOC. Also the direct photolysis quantum yield can be entered as a detailed wavelength trend, as a single value (constant or average), or it can be defined as a variable if unknown. APEX is based on the free software Octave. Additional applications are provided within APEX to assess the σ-level uncertainty of the results and the seasonal trend of photochemical processes.

  19. Polymorphisms in DNA Repair Genes (APEX1, XPD, XRCC1 and XRCC3 and Risk of Preeclampsia in a Mexican Mestizo Population

    Directory of Open Access Journals (Sweden)

    Ada Sandoval-Carrillo

    2014-03-01

    Full Text Available Variations in genes involved in DNA repair systems have been proposed as risk factors for the development of preeclampsia (PE. We conducted a case-control study to investigate the association of Human apurinic/apyrimidinic (AP endonuclease (APEX1 Asp148Glu (rs1130409, Xeroderma Pigmentosum group D (XPD Lys751Gln (rs13181, X-ray repair cross-complementing group 1 (XRCC Arg399Gln (rs25487 and X-ray repair cross-complementing group 3 (XRCC3 Thr241Met (rs861539 polymorphisms with PE in a Mexican population. Samples of 202 cases and 350 controls were genotyped using RTPCR. Association analyses based on a χ2 test and binary logistic regression were performed to determine the odds ratio (OR and a 95% confidence interval (95% CI for each polymorphism. The allelic frequencies of APEX1 Asp148Glu polymorphism showed statistical significant differences between preeclamptic and normal women (p = 0.036. Although neither of the polymorphisms proved to be a risk factor for the disease, the APEX1 Asp148Glu polymorphism showed a tendency of association (OR: 1.74, 95% CI = 0.96–3.14 and a significant trend (p for trend = 0.048. A subgroup analyses revealed differences in the allelic frequencies of APEX1 Asp148Glu polymorphism between women with mild preeclampsia and severe preeclampsia (p = 0.035. In conclusion, our results reveal no association between XPD Lys751Gln, XRCC Arg399Gln and XRCC3 Thr241Met polymorphisms and the risk of PE in a Mexican mestizo population; however, the results in the APEX1 Asp148Glu polymorphism suggest the need for future studies using a larger sample size.

  20. Development and evaluation of the bacterial fate and transport module for the Agricultural Policy/Environmental eXtender (APEX) model.

    Science.gov (United States)

    Hong, Eun-Mi; Park, Yongeun; Muirhead, Richard; Jeong, Jaehak; Pachepsky, Yakov A

    2018-02-15

    The Agricultural Policy/Environmental eXtender (APEX) is a watershed-scale water quality model that includes detailed representation of agricultural management. The objective of this work was to develop a process-based model for simulating the fate and transport of manure-borne bacteria on land and in streams with the APEX model. The bacteria model utilizes manure erosion rates to estimate the amount of edge-of-field bacteria export. Bacteria survival in manure is simulated as a two-stage process separately for each manure application event. In-stream microbial fate and transport processes include bacteria release from streambeds due to sediment resuspension during high flow events, active release from the streambed sediment during low flow periods, bacteria settling with sediment, and survival. Default parameter values were selected from published databases and evaluated based on field observations. The APEX model with the newly developed microbial fate and transport module was applied to simulate fate and transport of the fecal indicator bacterium Escherichia coli in the Toenepi watershed, New Zealand that was monitored for seven years. The stream network of the watershed ran through grazing lands with daily bovine waste deposition. Results show that the APEX with the bacteria module reproduced well the monitored pattern of E. coli concentrations at the watershed outlet. The APEX with the microbial fate and transport module will be utilized for predicting microbial quality of water as affected by various agricultural practices, evaluating monitoring protocols, and supporting the selection of management practices based on regulations that rely on fecal indicator bacteria concentrations. Published by Elsevier B.V.

  1. Perilymph sampling from the cochlear apex: a reliable method to obtain higher purity perilymph samples from scala tympani.

    Science.gov (United States)

    Salt, Alec N; Hale, Shane A; Plonkte, Stefan K R

    2006-05-15

    Measurements of drug levels in the fluids of the inner ear are required to establish kinetic parameters and to determine the influence of specific local delivery protocols. For most substances, this requires cochlear fluids samples to be obtained for analysis. When auditory function is of primary interest, the drug level in the perilymph of scala tympani (ST) is most relevant, since drug in this scala has ready access to the auditory sensory cells. In many prior studies, ST perilymph samples have been obtained from the basal turn, either by aspiration through the round window membrane (RWM) or through an opening in the bony wall. A number of studies have demonstrated that such samples are likely to be contaminated with cerebrospinal fluid (CSF). CSF enters the basal turn of ST through the cochlear aqueduct when the bony capsule is perforated or when fluid is aspirated. The degree of sample contamination has, however, not been widely appreciated. Recent studies have shown that perilymph samples taken through the round window membrane are highly contaminated with CSF, with samples greater than 2microL in volume containing more CSF than perilymph. In spite of this knowledge, many groups continue to sample from the base of the cochlea, as it is a well-established method. We have developed an alternative, technically simple method to increase the proportion of ST perilymph in a fluid sample. The sample is taken from the apex of the cochlea, a site that is distant from the cochlear aqueduct. A previous problem with sampling through a perforation in the bone was that the native perilymph rapidly leaked out driven by CSF pressure and was lost to the middle ear space. We therefore developed a procedure to collect all the fluid that emerged from the perforated apex after perforation. We evaluated the method using a marker ion trimethylphenylammonium (TMPA). TMPA was applied to the perilymph of guinea pigs either by RW irrigation or by microinjection into the apical turn. The

  2. Metal-Insulator Transition in Copper Oxides Induced by Apex Displacements

    Directory of Open Access Journals (Sweden)

    Swagata Acharya

    2018-05-01

    Full Text Available High temperature superconductivity has been found in many kinds of compounds built from planes of Cu and O, separated by spacer layers. Understanding why critical temperatures are so high has been the subject of numerous investigations and extensive controversy. To realize high temperature superconductivity, parent compounds are either hole doped, such as La_{2}CuO_{4} (LCO with Sr (LSCO, or electron doped, such as Nd_{2}CuO_{4} (NCO with Ce (NCCO. In the electron-doped cuprates, the antiferromagnetic phase is much more robust than the superconducting phase. However, it was recently found that the reduction of residual out-of-plane apical oxygen dramatically affects the phase diagram, driving those compounds to a superconducting phase. Here we use a recently developed first-principles method to explore how displacement of the apical oxygen (AO in LCO affects the optical gap, spin and charge susceptibilities, and superconducting order parameter. By combining quasiparticle self-consistent GW (QS GW and dynamical mean-field theory (DMFT, we show that LCO is a Mott insulator, but small displacements of the apical oxygen drive the compound to a metallic state through a localization-delocalization transition, with a concomitant maximum in d-wave order parameter at the transition. We address the question of whether NCO can be seen as the limit of LCO with large apical displacements, and we elucidate the deep physical reasons why the behavior of NCO is so different from the hole-doped materials. We shed new light on the recent correlation observed between T_{c} and the charge transfer gap, while also providing a guide towards the design of optimized high-T_{c} superconductors. Further, our results suggest that strong correlation, enough to induce a Mott gap, may not be a prerequisite for high-T_{c} superconductivity.

  3. Clinical study of toe ulcer and necrosis of the apex of the distal phalanx in 53 cattle

    International Nuclear Information System (INIS)

    Kofler, J.

    1999-01-01

    Clinical signs, causative factors, radiographic findings, type and duration of treatment or reason for killing were evaluated in 53 cattle (mean age: 5.3 years) suffering from toe ulcer and/or apical pedal bone necrosis. A total of 78 claws were affected. Four cattle suffered from a toe ulcer in one claw, 35 cattle showed osteolysis of the apex of the distal phalanx in a single claw and 14 cattle in two or three claws per cow. Overtrimming by means of a grinding disc and/or perforation of the sole was diagnosed as the major cause in 27 cattle (49%), laminitis in 30.2% and traumatic injuries in 11.3%. Radiography revealed a varying degree of osteolysis involving up to two-thirds of the pedal bone. Twenty-one cattle (39.6%) showing multiple toe disorders or involvement of one single claw with concurrent internal diseases were destroyed. In 23 cattle, the osteolytic bone was resected using a bone curette or hammer and chisel. Of these, the treatment was successful in 20 animals. The healing period ranged from 16-60 days when one claw was affected and from 43-53 days when two claws were affected. In five cattle, the digit was amputated

  4. Factors affecting individual foraging specialization and temporal diet stability across the range of a large "generalist" apex predator.

    Science.gov (United States)

    Rosenblatt, Adam E; Nifong, James C; Heithaus, Michael R; Mazzotti, Frank J; Cherkiss, Michael S; Jeffery, Brian M; Elsey, Ruth M; Decker, Rachel A; Silliman, Brian R; Guillette, Louis J; Lowers, Russell H; Larson, Justin C

    2015-05-01

    Individual niche specialization (INS) is increasingly recognized as an important component of ecological and evolutionary dynamics. However, most studies that have investigated INS have focused on the effects of niche width and inter- and intraspecific competition on INS in small-bodied species for short time periods, with less attention paid to INS in large-bodied reptilian predators and the effects of available prey types on INS. We investigated the prevalence, causes, and consequences of INS in foraging behaviors across different populations of American alligators (Alligator mississippiensis), the dominant aquatic apex predator across the southeast US, using stomach contents and stable isotopes. Gut contents revealed that, over the short term, although alligator populations occupied wide ranges of the INS spectrum, general patterns were apparent. Alligator populations inhabiting lakes exhibited lower INS than coastal populations, likely driven by variation in habitat type and available prey types. Stable isotopes revealed that over longer time spans alligators exhibited remarkably consistent use of variable mixtures of carbon pools (e.g., marine and freshwater food webs). We conclude that INS in large-bodied reptilian predator populations is likely affected by variation in available prey types and habitat heterogeneity, and that INS should be incorporated into management strategies to efficiently meet intended goals. Also, ecological models, which typically do not consider behavioral variability, should include INS to increase model realism and applicability.

  5. Factors affecting individual foraging specialization and temporal diet stability across the range of a large “generalist” apex predator

    Science.gov (United States)

    Rosenblatt, Adam E.; Nifong, James C.; Heithaus, Michael R.; Mazzotti, Frank J.; Cherkiss, Michael S.; Jeffery, Brian M.; Elsey, Ruth M.; Decker, Rachel A.; Silliman, Brian R.; Guillette, Louis J.; Lowers, Russell H.; Larson, Justin C.

    2015-01-01

    Individual niche specialization (INS) is increasingly recognized as an important component of ecological and evolutionary dynamics. However, most studies that have investigated INS have focused on the effects of niche width and inter- and intraspecific competition on INS in small-bodied species for short time periods, with less attention paid to INS in large-bodied reptilian predators and the effects of available prey types on INS. We investigated the prevalence, causes, and consequences of INS in foraging behaviors across different populations of American alligators (Alligator mississippiensis), the dominant aquatic apex predator across the southeast US, using stomach contents and stable isotopes. Gut contents revealed that, over the short term, although alligator populations occupied wide ranges of the INS spectrum, general patterns were apparent. Alligator populations inhabiting lakes exhibited lower INS than coastal populations, likely driven by variation in habitat type and available prey types. Stable isotopes revealed that over longer time spans alligators exhibited remarkably consistent use of variable mixtures of carbon pools (e.g., marine and freshwater food webs). We conclude that INS in large-bodied reptilian predator populations is likely affected by variation in available prey types and habitat heterogeneity, and that INS should be incorporated into management strategies to efficiently meet intended goals. Also, ecological models, which typically do not consider behavioral variability, should include INS to increase model realism and applicability.

  6. Clinical study of toe ulcer and necrosis of the apex of the distal phalanx in 53 cattle.

    Science.gov (United States)

    Kofler, J

    1999-03-01

    Clinical signs, causative factors, radiographic findings, type and duration of treatment or reason for killing were evaluated in 53 cattle (mean age: 5.3 years) suffering from toe ulcer and/or apical pedal bone necrosis. A total of 78 claws were affected. Four cattle suffered from a toe ulcer in one claw, 35 cattle showed osteolysis of the apex of the distal phalanx in a single claw and 14 cattle in two or three claws per cow. Overtrimming by means of a grinding disc and/or perforation of the sole was diagnosed as the major cause in 27 cattle (49%), laminitis in 30.2% and traumatic injuries in 11.3%. Radiography revealed a varying degree of osteolysis involving up to two-thirds of the pedal bone. Twenty-one cattle (39.6%) showing multiple toe disorders or involvement of one single claw with concurrent internal diseases were destroyed. In 23 cattle, the osteolytic bone was resected using a bone curette or hammer and chisel. Of these, the treatment was successful in 20 animals. The healing period ranged from 16-60 days when one claw was affected and from 43-53 days when two claws were affected. In five cattle, the digit was amputated.

  7. Chordoma of the petrous apex - a case report and review of the literature; Cordoma de apice petroso - relato de um caso e revisao da literatura

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Ricardo; Leal Junior, Osvaldo S. [Pernambuco Univ., Recife, PE (Brazil). Faculdade de Medicina; Loureiro, Lautonio Junior [Universidade de Pernambuco, Recife, PE (Brazil). Faculdade de Ciencias Medicas; Buril, Marlus V.M. [Hospital das Clinicas, Recife, PE (Brazil). Centro de Terapia Intensiva

    1998-10-01

    Chordomas are rare tumours arising from remnants of the embryologic notochord, typically at a midline position. Although 35-40% of these lesions are intracranial, these tumors answer for less than 1% of all intracranial tumors. The intracranial chordomas originate most frequently from the clival region at the midline. Nevertheless eventually may arise off the midline primarily in petrous apex or, very rarely, in paranasal sinuses. The authors report a case of histopathologically proved intracranial chordoma that arose atypical site in the petrous apex. The computed tomographic and magnetic resonance imaging finding were similar to those observed in midline chordomas. The computed tomographic examination revealed a well-defined soft tissue mass associated with bone destruction and foci of calcification. The magnetic resonance imaging study demonstrated a growing extra-axial formation that appeared with hypo-intensity of signal on T1-weighted images, hyperintensity on T2-weighted images and heterogeneous enhancement after paramagnetic agent injection. (author) 8 refs., 8 figs.

  8. Two dimensional vibrations of the guinea pig apex organ of Corti measured in vivo using phase sensitive Fourier domain optical coherence tomography

    Science.gov (United States)

    Ramamoorthy, Sripriya; Zhang, Yuan; Petrie, Tracy; Fridberger, Anders; Ren, Tianying; Wang, Ruikang; Jacques, Steven L.; Nuttall, Alfred L.

    2015-02-01

    In this study, we measure the in vivo apical-turn vibrations of the guinea pig organ of Corti in both axial and radial directions using phase-sensitive Fourier domain optical coherence tomography. The apical turn in guinea pig cochlea has best frequencies around 100 - 500 Hz which are relevant for human speech. Prior measurements of vibrations in the guinea pig apex involved opening the otic capsule, which has been questioned on the basis of the resulting changes to cochlear hydrodynamics. Here this limitation is overcome by measuring the vibrations through bone without opening the otic capsule. Furthermore, we have significantly reduced the surgery needed to access the guinea pig apex in the axial direction by introducing a miniature mirror inside the bulla. The method and preliminary data are discussed in this article.

  9. Animal-Borne Imaging Reveals Novel Insights into the Foraging Behaviors and Diel Activity of a Large-Bodied Apex Predator, the American Alligator (Alligator mississippiensis)

    OpenAIRE

    Nifong, James C.; Nifong, Rachel L.; Silliman, Brian R.; Lowers, Russell H.; Guillette, Louis J.; Ferguson, Jake M.; Welsh, Matthew; Abernathy, Kyler; Marshall, Greg

    2014-01-01

    Large-bodied, top- and apex predators (e.g., crocodilians, sharks, wolves, killer whales) can exert strong top-down effects within ecological communities through their interactions with prey. Due to inherent difficulties while studying the behavior of these often dangerous predatory species, relatively little is known regarding their feeding behaviors and activity patterns, information that is essential to understanding their role in regulating food web dynamics and ecological processes. Here...

  10. The simulation model of growth and cell divisions for the root apex with an apical cell in application to Azolla pinnata.

    Science.gov (United States)

    Piekarska-Stachowiak, Anna; Nakielski, Jerzy

    2013-12-01

    In contrast to seed plants, the roots of most ferns have a single apical cell which is the ultimate source of all cells in the root. The apical cell has a tetrahedral shape and divides asymmetrically. The root cap derives from the distal division face, while merophytes derived from three proximal division faces contribute to the root proper. The merophytes are produced sequentially forming three sectors along a helix around the root axis. During development, they divide and differentiate in a predictable pattern. Such growth causes cell pattern of the root apex to be remarkably regular and self-perpetuating. The nature of this regularity remains unknown. This paper shows the 2D simulation model for growth of the root apex with the apical cell in application to Azolla pinnata. The field of growth rates of the organ, prescribed by the model, is of a tensor type (symplastic growth) and cells divide taking principal growth directions into account. The simulations show how the cell pattern in a longitudinal section of the apex develops in time. The virtual root apex grows realistically and its cell pattern is similar to that observed in anatomical sections. The simulations indicate that the cell pattern regularity results from cell divisions which are oriented with respect to principal growth directions. Such divisions are essential for maintenance of peri-anticlinal arrangement of cell walls and coordinated growth of merophytes during the development. The highly specific division program that takes place in merophytes prior to differentiation seems to be regulated at the cellular level.

  11. Dexamethasone levels and base-to-apex concentration gradients in the scala tympani perilymph after intracochlear delivery in the guinea pig.

    Science.gov (United States)

    Hahn, Hartmut; Salt, Alec N; Biegner, Thorsten; Kammerer, Bernd; Delabar, Ursular; Hartsock, Jared J; Plontke, Stefan K

    2012-06-01

    To determine whether intracochlearly applied dexamethasone will lead to better control of drug levels, higher peak concentrations, and lower base-to-apex concentration gradients in the scala tympani (ST) of the guinea pig than after intratympanic (round window [RW]) application. Local application of drugs to the RW results in substantial variation of intracochlear drug levels and significant base-to-apex concentration gradients in ST. Two microliters of dexamethasone-phosphate (10 mg/ml) were injected into ST either through the RW membrane, which was covered with 1% sodium hyaluronate gel or through a cochleostomy with a fluid tight seal of the micropipette. Perilymph was sequentially sampled from the apex at a single time point for each animal, at 20, 80, or 200 min after the injection ended. Results were mathematically interpreted by means of an established computer model and compared with previous experiments performed by our group with the same experimental techniques but using intratympanic applications. Single intracochlear injections of 20 minutes resulted in approximately 10 times higher peak concentrations (on average) than 2 to 3 hours of intratympanic application to the RW niche. Intracochlear drug levels were less variable and could be measured for over 220 minutes. Concentration gradients along the scala tympani were less pronounced. The remaining variability in intracochlear drug levels was attributable to perilymph and drug leak from the injection site. With significantly higher, less variable drug levels and smaller base-to-apex concentration gradients, intracochlear applications have advantages to intratympanic injections. For further development of this technique, it is of importance to control leaks of perilymph and drug from the injection site and to evaluate its clinical feasibility and associated risks.

  12. Combined Endoscopic Transorbital and Endonasal Repair of High Flow Orbital Apex/Middle Fossa Cerebrospinal Fluid Leak with a Nasoseptal Flap.

    Science.gov (United States)

    Lucke-Wold, Brandon; Mendez, Gustavo; Cua, David; Akins, Paul; Gillham, Haley; Ciporen, Jeremy

    2018-01-01

    High flow orbital apex or middle fossa cerebrospinal fluid (CSF) leaks can be life threatening and complex to repair. These leaks associated with large dural defects are most commonly repaired with an open temporalis muscle patch or free flaps, but these flaps do not always stop the leak. A 65-year-old patient presented two years after orbital exenteration and radiation for squamous cell carcinoma. He developed multi-organism meningitis and pneumocephalus secondary to a large high-flow orbital apex/middle fossa CSF leak. To repair the leak, a combined endoscopic transorbital/endonasal approach with pedicled nasospetal flap and dermis fat graft was used. We describe the unique endoscopic technique that was used to treat the life threatening high flow orbital apex/middle fossa CSF leak. The technique allowed the use of the transposed pedicled flap, which is an alternative to the free flap in controlling CSF leak. Cisternogram post-operatively and clinical exam confirmed resolution of CSF leak. Although a critically ill patient at admission with a modified Rankin scale (MRS) of 5, he was discharged home on continued IV antibiotic therapy with a MRS of 3. Endoscopic evaluation at three months after treatment showed the effectiveness of the flap and he continued to improve clinically. This is the first case to describe a combined endoscopic transorbital and endonasal repair of high flow orbital apex/middle fossa CSF leak with a pedicled nasoseptal flap. These techniques can be utilized during initial reconstruction after orbital exenteration or as a salvage flap.

  13. Farside explorer

    DEFF Research Database (Denmark)

    Mimoun, David; Wieczorek, Mark A.; Alkalai, Leon

    2012-01-01

    the primary differentiation and evolution of the Moon, it can be continuously monitored from the Earth-Moon L2 Lagrange point, and there is a complete lack of reflected solar illumination from the Earth. Farside Explorer will exploit these properties and make the first radio-astronomy measurements from...... the most radio-quiet region of near-Earth space, determine the internal structure and thermal evolution of the Moon, from crust to core, and quantify impact hazards in near-Earth space by the measurement of flashes generated by impact events. The Farside Explorer flight system includes two identical solar......Farside Explorer is a proposed Cosmic Vision medium-size mission to the farside of the Moon consisting of two landers and an instrumented relay satellite. The farside of the Moon is a unique scientific platform in that it is shielded from terrestrial radio-frequency interference, it recorded...

  14. Uranium exploration

    International Nuclear Information System (INIS)

    De Voto, R.H.

    1984-01-01

    This paper is a review of the methodology and technology that are currently being used in varying degrees in uranium exploration activities worldwide. Since uranium is ubiquitous and occurs in trace amounts (0.2 to 5 ppm) in virtually all rocks of the crust of the earth, exploration for uranium is essentially the search of geologic environments in which geologic processes have produced unusual concentrations of uranium. Since the level of concentration of uranium of economic interest is dependent on the present and future price of uranium, it is appropriate here to review briefly the economic realities of uranium-fueled power generation. (author)

  15. A study of thermal stratification in the cold legs during the subcooled blowdown phase of a loss of coolant accident in the OSU APEX thermal hydraulic testing facility

    International Nuclear Information System (INIS)

    Wachs, D. M.

    1998-01-01

    Thermal stratification, which has been linked to the occurrence of pressurized thermal shock (PTS), is observed to occur during the early stages of simulated loss of coolant accidents (LOCAS) in the Oregon State University Advanced Plant Experiment (OSU APEX) Thermal Hydraulic Test Facility. The OSU APEX Test Facility is a scaled model of the Westinghouse AP600 nuclear power plant. Analysis of the OSU APEX facility data has allowed the determination of an onset criteria for thermal stratification and has provided support for the postulated mechanisms leading to thermal stratification. CFX 4.1, a computational fluid dynamics code, was used to generate a model of the cold legs and the downcomer that described the phenomena occurring within them. Some mixing phenomena were predicted that lead to non-uniformity between the two cold legs attached to the steam generator on the side of the facility containing the Passive Residual Heat Removal (PRHR) injection system. The stratification was found to be two phase and unlikely to be a factor in PTS

  16. Field evaluation of regenerated plants by somatic embryogenesis from shoots apexes of axillary buds in ´Navolean’ (Musa spp., AAB.

    Directory of Open Access Journals (Sweden)

    Jorge López

    2005-04-01

    Full Text Available The use of shoots apexes from axilary buds for callus induction with embryogenic structures in plantain ‘Navolean’ (Group AAB permitted to develop a plant regeneration method through out somatic embryogenesis. In order to know the phenotypic variants that may be produced with the previously mentioned method , 1000 plants were planted in field conditions in comparison to those coming from somatic embryos obtained from multibuds as initial explants and organogenesis-derived plants (shoot tipsand conventionally derived plants (corms, during two growing cycles. The main morphological characters and yield components were evaluated. The total frequency of somaclonal variation during the first growing cycle in plants coming from somatic embryos obtained from shoots apexes from axilary buds as initial explants were 1.1%, and 8,6% in regenerated plants from somatic embryos obtained from multi-buds as initial explants. Later, in this same growing cycle, plants regenerated from somatic embryos (both sources showed a similar performance between them and they were significantly superior in all evaluated variants in comparison to corm-derived plants. In the second growing cycle, significant differences were not observed in yield components of suckers from evaluated plants, in spite of the propagation method used. With regard to somaclonal variation, the best performance was obtained with shoots apexes from axilary buds as explants. Finally, the feasibility of using the new method was shown. Key words: embryogenic cell suspensions, somaclonal variation

  17. College Explorer.

    Science.gov (United States)

    Ahl, David H.

    1985-01-01

    The "College Explorer" is a software package (for the 64K Apple II, IBM PC, TRS-80 model III and 4 microcomputers) which aids in choosing a college. The major features of this package (manufactured by The College Board) are described and evaluated. Sample input/output is included. (JN)

  18. Exploring Size.

    Science.gov (United States)

    Brand, Judith, Ed.

    1995-01-01

    "Exploring" is a magazine of science, art, and human perception that communicates ideas museum exhibits cannot demonstrate easily by using experiments and activities for the classroom. This issue concentrates on size, examining it from a variety of viewpoints. The focus allows students to investigate and discuss interconnections among…

  19. Squeezed between shells? The origin of the Lupus I molecular cloud. II. APEX CO and GASS H I observations

    Science.gov (United States)

    Gaczkowski, B.; Roccatagliata, V.; Flaischlen, S.; Kröll, D.; Krause, M. G. H.; Burkert, A.; Diehl, R.; Fierlinger, K.; Ngoumou, J.; Preibisch, T.

    2017-12-01

    Context. Lupus I cloud is found between the Upper Scorpius (USco) and Upper Centaurus-Lupus (UCL) subgroups of the Scorpius-Centaurus OB association, where the expanding USco H I shell appears to interact with a bubble currently driven by the winds of the remaining B stars of UCL. Aims: We investigate whether the Lupus I molecular could have formed in a colliding flow, and in particular, how the kinematics of the cloud might have been influenced by the larger scale gas dynamics. Methods: We performed APEX 13CO(2-1)and C18O(2-1) line observations of three distinct parts of Lupus I that provide kinematic information on the cloud at high angular and spectral resolution. We compare those results to the atomic hydrogen data from the GASS H I survey and our dust emission results presented in the previous paper. Based on the velocity information, we present a geometric model for the interaction zone between the USco shell and the UCL wind bubble. Results: We present evidence that the molecular gas of Lupus Iis tightly linked to the atomic material of the USco shell. The CO emission in Lupus Iis found mainly at velocities between vLSR = 3-6 km s-1, which is in the same range as the H I velocities. Thus, the molecular cloud is co-moving with the expanding USco atomic H I shell. The gas in the cloud shows a complex kinematic structure with several line-of-sight components that overlay each other. The nonthermal velocity dispersion is in the transonic regime in all parts of the cloud and could be injected by external compression. Our observations and the derived geometric model agree with a scenario in which Lupus Iis located in the interaction zone between the USco shell and the UCL wind bubble. Conclusions: The kinematics observations are consistent with a scenario in which the Lupus Icloud formed via shell instabilities. The particular location of Lupus I between USco and UCL suggests that counterpressure from the UCL wind bubble and pre-existing density enhancements

  20. The prognostic value of tip-to-apex distance (TAD index in intertrochanteric fractures fixed by dynamic hip screw

    Directory of Open Access Journals (Sweden)

    Ali Sadighi

    2012-11-01

    Full Text Available Intertrochanteric fractures (ITFs are the most common type of fractures requiring surgical intervention. They also have the highest surgical mortality among orthopedic operations. Among the many different techniques used for fixation of this type of fracture, use of the Dynamic Hip Screw (DHS has gained wide acceptance. This current study was designed to assess positive predictive value of tip-to-apex distance (TAD index in the prognosis of patients treated with DHS. The study was designed according to a descriptive-analytic protocol, made up of 100 cases of ITFs caused by falling, treated in the Shohada Orthopedic Center, Tabriz, Iran. All patients underwent lateral and antero-posterior hip X-ray to measure TAD index. The cohort was followed for three months after DHS placement. Of a total of 100 cases (53 male, 47 female with a mean age of 76.7 years (range 29-100 years, 43% had grade 4, 29% grade 3, 21% grade 5, 5% grade 2 and 2% grade 6 osteoporosis. The screw position was postero-inferior in 57%, central in 40% and superior in 3% of patients. Minimum and maximum TAD index were 20 and 28 mm, respectively. Mean TAD was 23.5 mm. There were no post-operative complications in 84% of cases. Screw failure was the most common complication in the remaining 16% of patients. The study shows a statistically significant correlation between TAD index and cut-off rate in patients with intertrochanteric fractures of femoral bone treated by DHS. This validates the use of TAD index in determining the prognosis of patients treated by DHS.

  1. A comparative cost analysis of polytrauma and neurosurgery Intensive Care Units at an apex trauma care facility in India.

    Science.gov (United States)

    Kumar, Parmeshwar; Jithesh, V; Gupta, Shakti Kumar

    2016-07-01

    Although Intensive Care Units (ICUs) only account for 10% of the hospital beds, they consume nearly 22% of the hospital resources. Few definitive costing studies have been conducted in Indian settings that would help determine appropriate resource allocation. The aim of this study was to evaluate and compare the cost of intensive care delivery between multispecialty and neurosurgery ICUs at an apex trauma care facility in India. The study was conducted in a polytrauma and neurosurgery ICU at a 203-bedded Level IV trauma care facility in New Delhi, India, from May 1, 2012 to June 30, 2012. The study was cross-sectional, retrospective, and record-based. Traditional costing was used to arrive at the cost for both direct and indirect cost estimates. The cost centers included in the study were building cost, equipment cost, human resources, materials and supplies, clinical and nonclinical support services, engineering maintenance cost, and biomedical waste management. Statistical analysis was performed by Fisher's two tailed t-test. Total cost/bed/day for the multispecialty ICU was Rs. 14,976.9/- and for the neurosurgery ICU, it was Rs. 14,306.7/-, workforce constituting nearly half of the expenditure in both ICUs. The cost center wise and overall difference in the cost among the ICUs were statistically significant. Quantification of expenditure in running an ICU in a trauma center would assist health-care decision makers in better allocation of resources. Although multispecialty ICUs are more cost-effective, other factors will also play a role in defining the kind of ICU that needs to be designed.

  2. The prognostic value of tip-to-apex distance (TAD index) in intertrochanteric fractures fixed by dynamic hip screw.

    Science.gov (United States)

    Sedighi, Ali; Sales, Jafar Ganjpour; Alavi, Sahar

    2012-11-02

    Intertrochanteric fractures (ITFs) are the most common type of fractures requiring surgical intervention. They also have the highest surgical mortality among orthopedic operations. Among the many different techniques used for fixation of this type of fracture, use of the Dynamic Hip Screw (DHS) has gained wide acceptance. This current study was designed to assess positive predictive value of tip-to-apex distance (TAD) index in the prognosis of patients treated with DHS. The study was designed according to a descriptive-analytic protocol, made up of 100 cases of ITFs caused by falling, treated in the Shohada Orthopedic Center, Tabriz, Iran. All patients underwent lateral and antero-posterior hip X-ray to measure TAD index. The cohort was followed for three months after DHS placement. Of a total of 100 cases (53 male, 47 female) with a mean age of 76.7 years (range 29-100 years), 43% had grade 4, 29% grade 3, 21% grade 5, 5% grade 2 and 2% grade 6 osteoporosis. The screw position was postero-inferior in 57%, central in 40% and superior in 3% of patients. Minimum and maximum TAD index were 20 and 28 mm, respectively. Mean TAD was 23.5 mm. There were no post-operative complications in 84% of cases. Screw failure was the most common complication in the remaining 16% of patients. The study shows a statistically significant correlation between TAD index and cut-off rate in patients with intertrochanteric fractures of femoral bone treated by DHS. This validates the use of TAD index in determining the prognosis of patients treated by DHS.

  3. Unit Cost Analysis of PET-CT at an Apex Public Sector Health Care Institute in India.

    Science.gov (United States)

    Gajuryal, S H; Daga, A; Siddharth, V; Bal, C S; Satpathy, S

    2017-01-01

    PET/CT scan service is one of the capital intensive and revenue-generating centres of a tertiary care hospital. The cost associated with the provisioning of PET services is dependent upon the unit costs of the resources consumed. The study aims to determine the cost of providing PET/CT Scan services in a hospital. This descriptive and observational study was conducted in the Department of Nuclear Medicine at a tertiary apex teaching hospital in New Delhi, India in the year 2014-15. Traditional costing methodology was used for calculating the unit cost of PET/CT scan service. The cost was calculated under two heads that is capital and operating cost. Annualized cost of capital assets was calculated using methodology prescribed by WHO and operating costs was taken on an actual basis. Average number of PET/CT scan performed in a day is 30. The annual cost of providing PET/CT scan services was calculated to be 65,311,719 Indian Rupees (INR) (US$ 1,020,496), while the unit cost of PET scan was calculated to be 9625.92 INR (US$ 150). 3/4th cost was spent on machinery and equipment (75.3%) followed by healthcare personnel (11.37%), electricity (5%), consumables and supplies (4%) engineering maintenance (3.24%), building, furniture and HVAC capital cost (0.76%), and manifold cost (0.05%). Of the total cost, 76% was capital cost while the remaining was operating cost. Total cost for establishing PET/CT scan facility with cyclotron and chemistry module and PET/CT scan without cyclotron and chemistry module was calculated to be INR 610,873,517 (US$9944899) and 226,745,158 (US$3542893), respectively. (US$ 1=INR 64).

  4. Effective treatment of Stage I uterine papillary serous carcinoma with high dose-rate vaginal apex radiation (192Ir) and chemotherapy

    International Nuclear Information System (INIS)

    Turner, Bruce C.; Knisely, Jonathan P. S.; Kacinski, Barry M.; Haffty, Bruce G.; Gumbs, Andrew A.; Roberts, Kenneth B.; Frank, Alex H.; Peschel, Richard E.; Rutherford, Thomas J.; Edraki, Babak; Kohorn, Ernest I.; Chambers, Setsuko K.; Schwartz, Peter E.; Wilson, Lynn D.

    1998-01-01

    Purpose: Uterine papillary serous carcinoma (UPSC) is a morphologically distinct variant of endometrial carcinoma that is associated with a poor prognosis, high recurrence rate, frequent clinical understaging, and poor response to salvage treatment. We retrospectively analyzed local control, actuarial overall survival (OS), actuarial disease-free survival (DFS), salvage rate, and complications for patients with Federation International of Gynecology and Obstetrics (FIGO) (1988) Stage I UPSC. Methods and Materials: This retrospective analysis describes 38 patients with FIGO Stage I UPSC who were treated with the combinations of radiation therapy, chemotherapy, total abdominal hysterectomy, and bilateral salpingo-oophorectomy (TAH/BSO), with or without a surgical staging procedure. Twenty of 38 patients were treated with a combination of low dose-rate (LDR) uterine/vaginal brachytherapy using 226 Ra or 137 Cs and conventional whole-abdomen radiation therapy (WART) or whole-pelvic radiation therapy (WPRT). Of 20 patients (10%) in this treatment group, 2 received cisplatin chemotherapy. Eighteen patients were treated with high dose-rate (HDR) vaginal apex brachytherapy using 192 Ir with an afterloading device and cisplatin, doxorubicin, and cyclophosphamide (CAP) chemotherapy (5 of 18 patients). Only 6 of 20 UPSC patients treated with combination LDR uterine/vaginal brachytherapy and conventional external beam radiotherapy underwent complete surgical staging, consisting of TAH/BSO, pelvic/para-aortic lymph node sampling, omentectomy, and peritoneal fluid analysis, compared to 15 of 18 patients treated with HDR vaginal apex brachytherapy. Results: The 5-year actuarial OS for patients with complete surgical staging and adjuvant radiation/chemotherapy treatment was 100% vs. 61% for patients without complete staging (p = 0.002). The 5-year actuarial OS for all Stage I UPSC patients treated with postoperative HDR vaginal apex brachytherapy and systemic chemotherapy was 94

  5. Exploring quadrangulations

    KAUST Repository

    Peng, Chi-Han; Barton, Michael; Jiang, Caigui; Wonka, Peter

    2014-01-01

    Here we presented a framework to explore quad mesh topologies. The core of our work is a systematic enumeration algorithm that can generate all possible quadrangular meshes inside a defined boundary with an upper limit of v3-v5 pairs. The algorithm is orders of magnitude more efficient than previous work. The combination of topological enumeration and shape-space exploration demonstrates that mesh topology has a powerful influence on geometry. The Fig. 18. A gallery of different quadrilateral meshes for a Shuriken. The quadrilaterals of the model were colored in a postprocess. Topological variations have distinctive, interesting patterns of mesh lines. © 2014 ACM 0730-0301/2014/01-ART3 15.00.

  6. Exploring quadrangulations

    KAUST Repository

    Peng, Chi-Han

    2014-02-04

    Here we presented a framework to explore quad mesh topologies. The core of our work is a systematic enumeration algorithm that can generate all possible quadrangular meshes inside a defined boundary with an upper limit of v3-v5 pairs. The algorithm is orders of magnitude more efficient than previous work. The combination of topological enumeration and shape-space exploration demonstrates that mesh topology has a powerful influence on geometry. The Fig. 18. A gallery of different quadrilateral meshes for a Shuriken. The quadrilaterals of the model were colored in a postprocess. Topological variations have distinctive, interesting patterns of mesh lines. © 2014 ACM 0730-0301/2014/01-ART3 15.00.

  7. Explorative Faktorenanalyse

    OpenAIRE

    Klopp, Eric

    2010-01-01

    Die explorative Faktorenanalyse (EFA) ist ein Verfahren aus der multivariaten Statistik. Mithilfe der Faktorenanalyse kann aus den Beobachtungen vieler manifester Variablen (z .B Items eines Fragebogens) auf wenige zugrunde liegende latente Variablen, die Faktoren genannt werden, geschlossen werden. Eine EFA führt zu einer Reduktion der Variablen auf wenige, den manifesten Variablen zugrunde liegende Faktoren. Der folgende Text gibt einen Überblick über die Grundlagen der EFA sowie der wichti...

  8. Exploring Science Through Polar Exploration

    Science.gov (United States)

    Pfirman, S. L.; Bell, R. E.; Zadoff, L.; Kelsey, R.

    2003-12-01

    Exploring the Poles is a First Year Seminar course taught at Barnard College, Columbia University. First Year Seminars are required of incoming students and are designed to encourage critical analysis in a small class setting with focused discussion. The class links historical polar exploration with current research in order to: introduce non-scientists to the value of environmental science through polar literature; discuss issues related to venturing into the unknown that are of relevance to any discipline: self-reliance, leadership, preparation, decisions under uncertainty; show students the human face of science; change attitudes about science and scientists; use data to engage students in exploring/understanding the environment and help them learn to draw conclusions from data; integrate research and education. These goals are met by bringing analysis of early exploration efforts together with a modern understanding of the polar environment. To date to class has followed the efforts of Nansen in the Fram, Scott and Amundsen in their race to the pole, and Shackleton's Endurance. As students read turn-of-the-century expedition journals, expedition progress is progressively revealed on an interactive map showing the environmental context. To bring the exploration process to life, students are assigned to expedition teams for specific years and the fates of the student "expeditions" are based on their own decisions. For example, in the Arctic, they navigate coastal sea ice and become frozen into the ice north of Siberia, re-creating Nansen's polar drift. Fates of the teams varied tremendously: some safely emerged at Fram Strait in 4 years, while others nearly became hopelessly lost in the Beaufort Gyre. Students thus learn about variability in the current polar environment through first hand experience, enabling them to appreciate the experiences, decisions, and, in some cases, the luck, of polar explorers. Evaluation by the Columbia Center for New Media, Teaching

  9. Space exploration

    CERN Document Server

    2009-01-01

    Space Exploration, is one book in the Britannica Illustrated Science Library Series that is correlated to the science curriculum in grades 5-8. The Britannica Illustrated Science Library is a visually compelling set that covers earth science, life science, and physical science in 16 volumes.  Created for ages 10 and up, each volume provides an overview on a subject and thoroughly explains it through detailed and powerful graphics-more than 1,000 per volume-that turn complex subjects into information that students can grasp.  Each volume contains a glossary with full definitions for vocabulary help and an index.

  10. Surface Composition Near the Trailing Hemisphere Apex on Europa: The Manannán Impact Crater and Neighboring Terrain

    Science.gov (United States)

    Dalton, J. B.; Prockter, L. M.; Shirley, J. H.; Kamp, L.; Phillips, C. B.; Valenti, M.

    2012-12-01

    The Manannán impact crater and surrounding areas were imaged by Galileo's Near Infrared Mapping Spectrometer (NIMS) during the C3 orbital encounter. We have applied a linear mixture model based on cryogenic infrared reflectance spectroscopy to a "despiked" version of this NIMS observation (C3ENLINEA01A) to estimate abundances of sulfuric acid hydrate, hydrated sulfate salts, water ice and brines in surface exposures. Here we supplement our previously reported abundance estimates (Dalton et al., 2011) with additional results from our ongoing investigation. New geologic mapping precisely registered to the NIMS observation allows the extraction of high-quality near-infrared spectra specific to individual geologic units and morphological features. Detailed high resolution geologic mapping indicates the likely presence of extensive deposits of impact melt materials largely filling the crater floor (Moore et al. 2001), together with surrounding continuous ejecta deposits that may have been excavated from Europa's interior. We find that the crater floor and nearby ejecta exhibit low sulfuric acid abundance relative to the surroundings, with the abundance increasing with radial distance. Where the ejecta begins to thin and break up, the spectral mixture resembles a combination of pre-existing, high-acid-content materials and cleaner, excavated water ice. Several geologic units exhibit significantly lower sulfuric acid hydrate than expected for this region near the trailing hemisphere apex, varying from 53-64 wt% over the observation. This suggests that these surface units have received a reduced cumulative radiation dose (electrons and ions) compared to nearby terrain; this in turn implies geologic youth. We will present model compositions for several of Manannán's key stratigraphic units, including the crater floor deposits and the adjacent chaos and linea. We will interpret these results in the context of ongoing investigations of the interplay of exogenic and

  11. Burned Area Detection and Burn Severity Assessment of a Heathland Fire in Belgium Using Airborne Imaging Spectroscopy (APEX

    Directory of Open Access Journals (Sweden)

    Lennert Schepers

    2014-02-01

    Full Text Available Uncontrolled, large fires are a major threat to the biodiversity of protected heath landscapes. The severity of the fire is an important factor influencing vegetation recovery. We used airborne imaging spectroscopy data from the Airborne Prism Experiment (APEX sensor to: (1 investigate which spectral regions and spectral indices perform best in discriminating burned from unburned areas; and (2 assess the burn severity of a recent fire in the Kalmthoutse Heide, a heathland area in Belgium. A separability index was used to estimate the effectiveness of individual bands and spectral indices to discriminate between burned and unburned land. For the burn severity analysis, a modified version of the Geometrically structured Composite Burn Index (GeoCBI was developed for the field data collection. The field data were collected in four different vegetation types: Calluna vulgaris-dominated heath (dry heath, Erica tetralix-dominated heath (wet heath, Molinia caerulea (grass-encroached heath, and coniferous woodland. Discrimination between burned and unburned areas differed among vegetation types. For the pooled dataset, bands in the near infrared (NIR spectral region demonstrated the highest discriminatory power, followed by short wave infrared (SWIR bands. Visible wavelengths performed considerably poorer. The Normalized Burn Ratio (NBR outperformed the other spectral indices and the individual spectral bands in discriminating between burned and unburned areas. For the burn severity assessment, all spectral bands and indices showed low correlations with the field data GeoCBI, when data of all pre-fire vegetation types were pooled (R2 maximum 0.41. Analysis per vegetation type, however, revealed considerably higher correlations (R2 up to 0.78. The Mid Infrared Burn Index (MIRBI had the highest correlations for Molinia and Erica (R2 = 0.78 and 0.42, respectively. In Calluna stands, the Char Soil Index (CSI achieved the highest correlations, with R2 = 0

  12. Geoelectrical exploration

    Directory of Open Access Journals (Sweden)

    Mostafa Said Barseem

    2015-12-01

    Full Text Available Sinai development is a goal of successive governments in Egypt. The present study is a geoelectrical exploration to find appropriate solutions of the problems affecting the land of a Research Station in Southeast Al Qantara. This research station is one of the Desert Research Center stations to facilitate the development of desert land for agriculture by introducing applied research. It suffers from some problems which can be summarized in the shortage of irrigation water and water logging. The appropriate solutions of these problems have been delineated by the results of 1D and 2D geoelectrical measurements. Electrical resistivity (ER revealed the subsurface sedimentary sequences and extension of subsurface layers in the horizontal and vertical directions, especially, the water bearing layer. Additionally it helped to choose the most suitable places to drill productive wells with a good condition.

  13. Exploration economics

    International Nuclear Information System (INIS)

    Mcgill, R.E.

    1992-01-01

    This paper deals with determining the economic viability of the play or prospect. At the outset, one point is important. Preexploration economists are important because they enable geologists to see if their assumptions will prove profitable. Their assumptions must consider the full range of possible outcomes, even if only some portion of that range may contain prospects or plays that are estimated to be profitable. Play economics are preferable to prospect economics because, being the sum of several prospects, they give a broader view of the investment opportunity. Finally, remember that play and prospect economics are always slightly optimistic. They seldom include all of the exploration and overhead changes that must ultimately be borne by the successful prospects

  14. HR Explorer

    CERN Document Server

    Möller, M

    1997-01-01

    At the European Laboratory for Particle Physics Research (CERN), Geneva Switzerland we are using OracleHR for managing our human resources since 1995. After the first year of production it became clear that there was a strong need for an easy-to-use Decision Support Tool exploring the data in OracleHR. This paper illustrates an approach which we have adopted to provide on-line management reporting, multi-dimensional analysis, drill-down and slicing & dicing of data, warehoused from OracleHR. The tool offers strong resource management and planning capabilities including career follow-up. The user management and security monitoring are implemented using the Oracle WebServer.

  15. Hydrocarbon exploration

    Energy Technology Data Exchange (ETDEWEB)

    Lerche, I. (South Carolina Univ., Columbia, SC (United States). Dept. of Geological Sciences)

    1993-01-01

    This special issue of the journal examines various aspects of the on-going search for hydrocarbons, ranging from frontier basins where little data are available, to more mature areas where considerable data are available. The incentives underlying the search for oil are roughly: the social, economic and industrial needs of a nation; the incentive of a corporation to be profitable; and the personal incentives of individuals in the oil industry and governments, which range from financial wealth to power and which are as diverse as the individuals who are involved. From a geopolitical perspective, the needs, requirements, goals, strategies, and philosophies of nations, and groups of nations, also impact on the oil exploration game. Strategies that have been employed have ranged from boycott to austerity and rationing, to physical intervention, to global ''flooding'' with oil by over-production. (author)

  16. Exploring ESASky

    Science.gov (United States)

    De Marchi, Guido; ESASky Team

    2017-06-01

    ESASky is a science-driven discovery portal for all ESA space astronomy missions. It also includes missions from international partners such as Suzaku and Chandra. The first public release of ESASky features interfaces for sky exploration and for single and multiple target searches. Using the application requires no prior-knowledge of any of the missions involved and gives users world-wide simplified access to high-level science-ready data products from space-based Astronomy missions, plus a number of ESA-produced source catalogues, including the Gaia Data Release 1 catalogue. We highlight here the latest features to be developed, including one that allows the user to project onto the sky the footprints of the JWST instruments, at any chosen position and orientation. This tool has been developed to aid JWST astronomers when they are defining observing proposals. We aim to include other missions and instruments in the near future.

  17. An in vitro evaluation of the accuracy of four electronic apex locators using stainless-steel and nickel-titanium hand files

    Directory of Open Access Journals (Sweden)

    Paras Mull Gehlot

    2016-02-01

    Full Text Available Objectives The purpose of this in vitro study was to evaluate the accuracy of working length (WL determination of four electronic apex locators (EALs, namely, Root ZX (RZX, Elements diagnostic unit and apex locator (ELE, SybronEndo Mini Apex locator (MINI and Propex pixi (PIXI using Stainless steel (SS and nickel-titanium (NiTi hand files. The null hypothesis was that there was no difference between canal length determination by SS and NiTi files of 4 EALs. Materials and Methods Sixty extracted, single rooted human teeth were decoronated and the canal orifice flared. The actual length (AL was assessed visually, and the teeth were embedded in an alginate model. The electronic length (EL measurements were recorded with all four EALs using SS and NiTi files at '0.5' reading on display. The differences between the AL and EL were compared. Results The results obtained with each EAL with SS and NiTi files were compared with AL. A paired sample t test showed that there was a statistical significant difference between EAL readings with SS and NiTi files for RZX and MINI (p < 0.05. The accuracy of RZX, ELE, MINI and PIXI within ± 0.5 mm of AL with SS/NiTi files were 93.3%/70%, 90%/91.7%, 95%/68.3%, and 83.3%/83.3%, respectively. Conclusions The results of this study indicate that Root ZX was statistically more accurate with NiTi files compared to SS files, while MINI was statistically more accurate with SS files compared to NiTi files. ELE and PIXI were not affected by the alloy type of the file used to determine WL.

  18. Analysis of AtGUS1 and AtGUS2 in Arabidopsis root apex by a highly sensitive TSA-MISH method.

    Science.gov (United States)

    Bruno, Leonardo; Ronchini, Matteo; Gagliardi, Olimpia; Corinti, Tamara; Chiappetta, Adriana; Gerola, Paolo; Bitonti, Maria B

    2015-01-01

    A new highly sensitive whole-mount in situ hybridization method, based on tyramide signal amplification (TSA-MISH) was developed and a combined GFP detection and TSA-MISH procedure was applied for the first time in plants, to precisely define the spatial pattern of AtGUS1 and AtGUS2 expression in the root apex. β-glucuronidases (GUSs) belonging to the glycosyl hydrolases (GHs) 79 family, are widely distributed in plants, but their functional role has not yet been fully investigated. In the model system Arabidopsis Thaliana, three different AtGUS genes have been identified which encode proteins with putative different fates. Endogenous GUS expression has been detected in different organs and tissues, but the cyto-histological domains of gene expression remain unclear. The results here reported show co-expression of AtGUS1 and AtGUS2 in different functional zones of the root apex (the cap central zone, the root cap meristem, the staminal cell niche and the cortical cell layers of the proximal meristem), while AtGUS2 is exclusively expressed in the cap peripheral layer and in the epidermis in the elongation zone. Interestingly, both genes are not expressed in the stelar portion of the proximal meristem. A spatial (cortex vs. stele) and temporal (proximal meristem vs. transition zone) regulation of AtGUS1 and AtGUS2 expression is therefore active in the root apex. This expression pattern, although globally consistent with the involvement of GUS activity in both cell proliferation and elongation, clearly indicates that AtGUS1 and AtGUS2 could control distinct downstream process depending on the developmental context and the interaction with other players of root growth control. In the future, the newly developed approaches may well be very useful to dissect such interactions.

  19. Space Exploration

    Science.gov (United States)

    Gallagher, Dennis

    2017-01-01

    New range Passage Tomb may be the first structure with known astronomical significance. It was built around 3,200 B.C. in Ireland. It's central passage allows light end-to-end for about 2 weeks around winter solstice. The Sun, Moon, Planets, and Stars held significance in early times due to the seasons, significance for food crops, and mythology. Citation: Corel Photography and Windows to the Universe The Greek may be among the first to pursue analytical interpretations of what they saw in the sky. In about 280 B.C. Aristarchus suggested Earth revolves around the Sun and estimated the distance between. Around 130 B.C. Hipparchus developed the first accurate star map. Today still seek to understand how the universe formed and how we came to be and are we alone. Understanding the causes and consequences of climate change using advanced space missions with major Earth science and applications research. center dotFire the public imagination and inspire students to pursue STEM fields. Train college and graduate students to create a U.S. technical workforce with employees that embody the values of competence, innovation, and service. center dotDrive the technical innovations that enable exploration and become the engine of National economic growth. center dotPartner domestically and internationally to leverage resources to extend the reach of research.

  20. Influence of the apex angle of a hollow prism made from an ordinary commercial glass plate as a simple refractometer to the accuracy of the refractive index measurement of the edible oil

    Science.gov (United States)

    Idris, N.; Maswati; Yusibani, E.

    2018-05-01

    The influence of the apex angle of a hollow prism used as a simple refractometer to the accuracy of a refractive index measurement of the edible oil samples was studied. The hollow prism was made from an ordinary commercial glass plate with a thickness of 2 mm. The apex angle of the constructed hollow prism was varied. The edible oil sample used in this study was palm oil, namely the packaged, branded oil sample and the bulk oil sample. For measuring the refractive index, the oil sample was filled in the constructed hollow prism, and then a helium-neon laser beam was passed through the oil sample at a certain angle of incidence. The angle of minimum deviation of the transmitted laser He-Ne beam was measured and then was used for calculating the refractive index of the oil sample. The refractive index measurement was made using the hollow prism with different apex angles, ranging from 300 to 600. The measurement accuracy was estimated by comparing the refractive index measured using the hollow prisms to that of obtained using a standard Abbe refractometer. It was found that the refractive index of the edible oil can be measured accurately by using the hollow prism. It was also found that the accuracy of the refractive index measurement significantly changes with the apex angle of the hollow prism. The refractive index values measured using this simple refractometer deviate up to 3,49% from the refractive index value measured using the standard Abbe refractometer, especially when the apex angle of the prism is 30°. The measurement results with high accuracies obtained when using the hollow prisms with apex angles of 450 and 600. The optimum apex angle for the present constructed hollow prism is 450. The refractive index obtained using the hollow prism with the apex angle of 450 is 1,4623 and 1,4438 for the bulk oil and the packed, branded oil samples, respectively. This result suggests that the apex angle of the prism used affects largely the accuracy of the

  1. Exploring Mars

    Science.gov (United States)

    Breuil, Stéphanie

    2016-04-01

    Mars is our neighbour planet and has always fascinated humans as it has been seen as a potential abode for life. Knowledge about Mars is huge and was constructed step by step through numerous missions. It could be difficult to describe these missions, the associated technology, the results, the questions they raise, that's why an activity is proposed, that directly interests students. Their production is presented in the poster. Step 1: The main Mars feature and the first Mars explorations using telescope are presented to students. It should be really interesting to present "Mars Canals" from Percival Lowell as it should also warn students against flawed interpretation. Moreover, this study has raised the big question about extra-terrestrial life on Mars for the first time. Using Google Mars is then a good way to show the huge knowledge we have on the planet and to introduce modern missions. Step 2: Students have to choose and describe one of the Mars mission from ESA and NASA. They should work in pairs. Web sites from ESA and NASA are available and the teacher makes sure the main missions will be studied. Step 3: Students have to collect different pieces of information about the mission - When? Which technology? What were the main results? What type of questions does it raise? They prepare an oral presentation in the form they want (role play, academic presentation, using a poster, PowerPoint). They also have to produce playing cards about the mission that could be put on a timeline. Step 4: As a conclusion, the different cards concerning different missions are mixed. Groups of students receive cards and they have to put them on a timeline as fast as possible. It is also possible to play the game "timeline".

  2. The Accuracy of the Digital imaging system and the frequency dependent type apex locator in root canal length measurement

    International Nuclear Information System (INIS)

    Lee, Byoung Rib; Park, Chang Seo

    1998-01-01

    In order to achieve a successful endodontic treatment, root canals must be obturated three-dimensionally without causing any damage to apical tissues. Accurate length determination of the root canal is critical in this case. For this reason, I've used the conventional periapical radiography, Digora (digital imaging system) and Root ZX (the frequency dependent type apex locator) to measure the length of the canal and compare it with the true length obtained by cutting the tooth in half and measuring the length between the occlusal surface and the apical foramen. From the information obtained by these measurements, I was able to evaluate the accuracy and clinical usefulness of each systems, whether the thickness of files used in endodontic therapy has any effect on the measuring systems was also evaluated in an effort to simplify the treatment planning phase of endodontic treatment. 29 canals of 29 sound premolars were measured with no 15, no 20, no 25 files by 3 different dentists each using the periapical radiography, Digora and Root ZX. The measurements were then compared with the true length. The results were as follows ; 1. In comparing mean discrepancies between measurements obtained by using periapical radiography (mean error : -0.449 ± 0.444 mm), Digora (mean error : -0.417 ± 0.415 mm) and Root ZX (mean error : 0.123 ± 0.458 mm) with true length, periapical radiography and Digora system had statistically significant differences (p 0.05). 2. By subtracting values obtained by using periapical radiography, Digora and Root ZX from the true length and making a distribution table of their absolute values, the following analysis was possible. In the case of periapical film, 140 out of 261 (53.6%) were clinically acceptable satisfying the margin of error of less than 0.5 mm, 151 out of 261 (53,6%) were acceptable in the Digora system while Root ZX had 197 out of 261 (75.5%) within the limits of 0.5 mm margin of error. 3. In determining whether the thickness of

  3. A Radiologic Study of the Relationship of the Maxillary Sinus Floor and Apex of the Maxillary Molar

    International Nuclear Information System (INIS)

    Yoon, Hae Rym; Park, Chang Seo

    1998-01-01

    In this study, radiographic evaluation was made using panoramic radiography and cross-sectional tomography of SCANORA in male and female adults in their 20 s on the relationship between the maxillary sinus floor and the apex of the maxillary molar, to test the accuracy and effectiveness of the cross-sectional tomography, and to use this information in the assessment of preop, and postop, root canal treatment, apical surgery, extraction and implantology. Forty-one adults with an average age of 24.4 years were studied panoramic radiography and cross-sectional tomography. In panoramic view and cross-sectional view, the position of the apices of maxillary molars were classified as separated, contacted, or protruded type; the general shape of the maxillary sinus floor was evaluated horizontally and vertically from cross-sectional tomography. The accuracy of each radiography was tested using maxilla from 5 fresh cadavers from the Anatomy Lab at Yonsei University Dental College, and panoramic view and cross-sectional tomography were taken in the same condition as with the patients. The results were as follows ; 1. Panoramic view and cross-sectional view were taken in the maxilla specimen, and the actual distance between the maxillary sinus floor and the tooth apices were measured in the specimen; the median values of the distance from the tooth apices to the maxillary sinus floor in the panoramic view, cross-sectional view and in the accrual maxilla specimen were 2.83 mm, 4.51 mm, and 4.15 mm, respectively. In the cross-sectional view, the measured distance was close to the actual distance but in the panoramic view, the measured distance was far from the actual distance. 2. When the results of the panoramic view and cross-sectional view were compared, 40.5% of the results agreed with each other in the two radiographic methods and buccal roots of the 2nd molar were the closest to the maxillary sinus floor in the cross-sectional tomography.3. In cross-sectional view, when

  4. Eggshell apex abnormalities in a free-range hen farm with mycoplasma synoviae and infectious bronchitis virus in Rio de Janeiro state, Brazil

    Directory of Open Access Journals (Sweden)

    FC dos Santos

    2014-06-01

    Full Text Available A farm with 3,000 free-range hens between 24 and 65 weeks of age was investigated. These hens were separated in small flocks of 400 to 700 birds, presenting 10 to 23% egg production reduction. Twenty serum samples were collected during the period of drop in egg production and three weeks later for the investigation of Mycoplasma synoviae (MS, M. gallisepticum (MG and Infectious Bronchitis Virus (IBV antibodies using ELISA. At the time of the second collection, egg production had resumed to normal levels; however, with 10.23% of the eggs showed eggshell abnormalities limited to the apex. Eggshell strength was significantly different between normal and those with eggshell apex abnormalities, but not other egg-quality parameters. ELISA tests showed that MS and IBV titers increased during the evaluated period. MS infection was confirmed by culture and by PCR of tracheal swabs. All samples were negative for MG by ELISA and PCR. Further studies with larger samples to ensure the occurrence of this disease in industrial layer flocks in Brazil are under way.

  5. Reliable lateral manipulation of a single Ag adatom on a Ag(1 1 1) surface with a trimer-apex tip

    International Nuclear Information System (INIS)

    Xie Yiqun; Shi Wangzhou; Du Guoping

    2009-01-01

    We study the reliability of the lateral manipulation of a single Ag adatom on a Ag(1 1 1) surface with the single-atom and trimer-apex tips based on molecular statics simulations using surface embedded-atom-method potential. The dependence of the manipulation reliability on tip height and orientation is investigated. For the single-atom tip the manipulation reliability increases monotonically with decreasing tip height, which is owing to the strengthened lateral tip-adatom interaction as the tip height lowers. For the trimer-apex tip, the manipulation reliability is sensitive to the tip orientation in the lower tip-height range, while in the higher tip-height range the manipulation reliability is independent of the tip orientation and moreover can be greatly improved due to the strong vertical attraction of the tip on the adatom as compared to the single-atom tip. We also compare these results to those for manipulating single Cu adatoms on the Cu(1 1 1) surface, reveal the underlying physics, and propose the method to improve the manipulation reliability for different systems.

  6. Laser ablation-inductively coupled plasma-dynamic reaction cell-mass spectrometry for the multi-element analysis of polymers

    International Nuclear Information System (INIS)

    Resano, M.; Garcia-Ruiz, E.; Vanhaecke, F.

    2005-01-01

    In this work, the potential of laser ablation-inductively coupled plasma-mass spectrometry for the fast analysis of polymers has been explored. Different real-life samples (polyethylene shopping bags, an acrylonitrile butadiene styrene material and various plastic bricks) as well as several reference materials (VDA 001 to 004, Cd in polyethylene) have been selected for the study. Two polyethylene reference materials (ERM-EC 680 and 681), for which a reference or indicative value for the most relevant metals is available, have proved their suitability as standards for calibration. Special attention has been paid to the difficulties expected for the determination of Cr at the μg g -1 level in this kind of materials, due to the interference of ArC + ions on the most abundant isotopes of Cr. The use of ammonia as a reaction gas in a dynamic reaction cell is shown to alleviate this problem, resulting in a limit of detection of 0.15 μg g -1 for this element, while limiting only modestly the possibilities of the technique for simultaneous multi-element analysis. In this regard, As is the analyte most seriously affected by the use of ammonia, and its determination has to be carried out in vented mode, at the expense of measuring time. In all cases studied, accurate results could be obtained for elements ranging in content from the sub-μg g -1 level to tens of thousands of μg g -1 . However, the use of an element of known concentration as internal standard may be needed for materials with a matrix significantly different from that of the standard (polyethylene in this work). Precision ranged between 5% and 10% RSD for elements found at the 10 μg g -1 level or higher, while this value could deteriorate to 20% for analytes found at the sub-μg g -1 level. Overall, the technique evaluated presents many advantages for the fast and accurate multi-element analysis of these materials, avoiding laborious digestion procedures and minimizing the risk of analyte losses due to the

  7. Animal-Borne Imaging Reveals Novel Insights into the Foraging Behaviors and Diel Activity of a Large-Bodied Apex Predator, the American Alligator (Alligator mississippiensis)

    Science.gov (United States)

    Nifong, James C.; Nifong, Rachel L.; Silliman, Brian R.; Lowers, Russell H.; Guillette, Louis J.; Ferguson, Jake M.; Welsh, Matthew; Abernathy, Kyler; Marshall, Greg

    2014-01-01

    Large-bodied, top- and apex predators (e.g., crocodilians, sharks, wolves, killer whales) can exert strong top-down effects within ecological communities through their interactions with prey. Due to inherent difficulties while studying the behavior of these often dangerous predatory species, relatively little is known regarding their feeding behaviors and activity patterns, information that is essential to understanding their role in regulating food web dynamics and ecological processes. Here we use animal-borne imaging systems (Crittercam) to study the foraging behavior and activity patterns of a cryptic, large-bodied predator, the American alligator (Alligator mississippiensis) in two estuaries of coastal Florida, USA. Using retrieved video data we examine the variation in foraging behaviors and activity patterns due to abiotic factors. We found the frequency of prey-attacks (mean = 0.49 prey attacks/hour) as well as the probability of prey-capture success (mean = 0.52 per attack) were significantly affected by time of day. Alligators attempted to capture prey most frequently during the night. Probability of prey-capture success per attack was highest during morning hours and sequentially lower during day, night, and sunset, respectively. Position in the water column also significantly affected prey-capture success, as individuals’ experienced two-fold greater success when attacking prey while submerged. These estimates are the first for wild adult American alligators and one of the few examples for any crocodilian species worldwide. More broadly, these results reveal that our understandings of crocodilian foraging behaviors are biased due to previous studies containing limited observations of cryptic and nocturnal foraging interactions. Our results can be used to inform greater understanding regarding the top-down effects of American alligators in estuarine food webs. Additionally, our results highlight the importance and power of using animal

  8. Bile Duct Exploration

    Science.gov (United States)

    ... Home / Health Library / Diagnostics & Testing / Bile Duct Exploration Bile Duct Exploration Common bile duct exploration is a ... Test Details Results and Follow-Up What is bile, and what is bile duct exploration? Bile is ...

  9. Tokamak transport phenomenology and plasma dynamic response

    International Nuclear Information System (INIS)

    Moret, J.M.; Association Euratom CEA, Centre d'Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance

    1991-07-01

    A system identification method is developed to estimate the transfer function of the system from the time evolution of its parameters to any excitation. The form of the identified transfer function is linked to a representation of the transport in terms of poles (eigenvalues) and eigenmodes. These eigenvalues and eigenvectors are thus directly deduced from the raw data with no restriction on the underlying processes and there is consequently no need to adjust any simplified transport model to the experimental data. This method is illustrated in this paper by analysing the injection of pellets on Tore Supra. The density and the temperature transfer functions were observed to share the same poles with the corresponding eigenmodes grouped in pairs with identical profiles. This implies the presence of a coupling between the particle and heat flow. A criterion is developed to select amongst the possible coupling mechanisms, based on compatibility with the observed transfer function. The selection suggests a model in which the particle diffusion coefficient depends on the density and on the temperature gradient

  10. Tokamak nonmaxwellian plasma dynamics in thermonuclear regime

    International Nuclear Information System (INIS)

    Cotsaftis, M.

    1987-01-01

    To reach ignition in a Tokamak plasma, large additional power P aux has to be injected in the device on top of the Joule heating P OH =VI r , V the plasma loop voltage, I r the resistive port of plasma current. Typi-cally JH ∼ 1 KeV, whereas ignition would requi- re IG ∼ 7-10 KeV. To gain this factor 7, one at least should inject additional power P aux ∼ 7P OH , supposing that nothing, especially the heat transport, is modified. This is by far not the case, with the so-called energy lifetime degradation, largely observed in oil experiments (but less dramatic with divertors), where energy lifetime tau E behaves like P tot -b with b∼1/2. In large machines where ignition temperature is the target to be imperiously reached, this implies to inject a very large power, typically P aux ∼ 50 to 100 MW, depending on size and parameters and on actual transport. So it is of importance with such figures, or even larger ones owing to uncertain ties, to optimize at best injected power by increasing its efficiency, both with respect to possible transport laws, and to physical phenomena governing heat flow in the system from the sources. This leads to the concept of scenarios, as time sequences of power input, where physical properties of the plasma system are used to build up ion temperature so that ignition is reached with minimum P tot = P OH + P aux and with fixed Q = Q o > 1. Elements for this study are given. The method is outlined. The resulting system of equations describing the evolution of a thermonuclear plasma is given

  11. Plasma dynamics from laser ablated solid lithium

    Indian Academy of Sciences (India)

    b; 52.25.-b; 52.70.-m. 1. Introduction. Pulsed laser ablation of a solid sample generates a dense plasma emission in the shape of ... The multichannel analyser plate of the ICCD was gated for as less as 4 ns using ... to explain the atomic collision processes [4]. .... Within duration of laser pulse, there occurs laser-solid interac-.

  12. Simulation of burning plasma dynamics in ITER

    International Nuclear Information System (INIS)

    Wang, J.F.; Amano, T.; Ogawa, Y.; Inoue, N.

    1996-02-01

    Dynamics of burning plasma for various transient situations in ITER plasma has been simulated with a 1.5-dimensional up-down asymmetry Tokamak Transport Simulation Code (TTSC). We have mainly paid attention to intrinsic plasma transport processes such as the confinement improvement and the change of plasma profiles. It is shown that a large excursion of the fusion power takes place with a small improvement of the plasma confinement; e.g., an increase of the global energy confinement by a factor of 1.22 yields the fusion power excursion of ∼ 30% within a few seconds. Any feedback control of fueling D-T gas is difficult to respond to this short time scale of fusion power transient. The effect of the plasma profile on the fusion power excursion has been studied, by changing the particle transport denoted by the inward pinch parameter C V . It is found that the fusion power excursion is mild and slow, and the feedback control is quite effective in suppressing the fusion power excursion and in shortening the duration time of power transient in this case. The change in the pumping efficiency has also been studied and a large excursion of the fusion power has not been observed, because of the decrease in the fuel density itself in the case of the increase in the pumping efficiency, and the helium ash accumulation in the case of the decrease in the pumping efficiency. Finally it is shown that the MHD sawteeth activity leads to the fusion power fluctuation of ± 20%, although it is helpful for the helium ash exhaust. (author)

  13. Plasma dynamics in a staged pinch device

    International Nuclear Information System (INIS)

    Khattak, N.A.D.; Ahmed, Z.; Mirza, A.M.; Murtaza, G.

    1998-01-01

    Plasma parameters in fiber initiated fast and dense theta-pinch plasma driven by an annular finite-thickness gas-puff Z-pinch are studied. The imploding gas-puff Z-pinch plasma traps an axial magnetic field B/sub z/, compressing it to large values (of the order of several megagauss) in an extremely short time. The rapidly changing magnetic flux of this field induces an azimuthal current on the surface of the coaxially placed fiber, with a rise time an order of magnitude shorter than the applied Z-pinch current. The shorter rise time of the current stabilizes the pinch against sausage mode of MHD instabilities. Our numerical results demonstrate that for a relatively thick gas-puff layer, the compression occurs before the current saturates. At the peak compression the fuel densities of the order of 10/sup 25/ cm/sup -3/ and temperature above 10 keV can be achieved on a time scale of 0.1 nanoseconds, yielding the Lawson Criterion parameters n tau is approximately equal to 10/sup 14/ sec cm/sup -3/ for D-T fuel. The snow-plow effect incorporated in our model exercise a strong influence on the onset and growth rate of sausage and Rayleigh-Taylor (R-T) modes of instabilities. Imposing a rotational velocity on the outer thin gas-puff plasma can control the Rayleigh-Taylor instability. Numerical results indicate that the choice of the spin velocity is critical. Large values of the spin velocity, though provide stabilization against the R-T instability at the final stage of compression, however, it adversely reduce the plasma parameters so essential to achieve controlled fusion. Our analysis, therefore, suggests that a judicious choice of the spin velocity is necessary to obtain the desired temperature and density, especially when we seed D-T fiber plasma with a small fraction of high-Z Kr impurity to initiate the radiative collapse. (author)

  14. Multislit streak photography for plasma dynamics studies

    International Nuclear Information System (INIS)

    Tou, T.Y.; Lee, S.

    1988-01-01

    A microscope slide with several transparent slits installed in a streak camera is used to record time-resolved two-dimensional information when a curved luminous plasma sheath traverses these slits. Applying this method to the plasma focus experiment, the axial run-down trajectory and the shapes of the plasma sheath at various moments can be obtained from a single streak photograph

  15. Stationary deviations from quasineutrality in plasma dynamics

    International Nuclear Information System (INIS)

    Sholin, G.V.; Trushin, S.A.

    1985-01-01

    The general assumption of quasineutrality of plasmas is broken in some cases. A self-consistent method is presented to solve the nonlinear differential equations of two-liquid hydrodynamics. The method is based on the theory of singularly perturbed differential equations of A.N. Tikhonov. The case of perpendicular magneto-acoustic wave of large amplitude is described. The rearrangement of the charges is related to the instability of root of the gendering system. (D.Gy.)

  16. JAXA's Space Exploration Scenario

    Science.gov (United States)

    Sato, N. S.

    2018-04-01

    Japan Aerospace Exploration Agency (JAXA) has been studying space exploration scenario, including human exploration for Japan since 2015, which encompasses goals, knowledge gap assessment, and architecture. assessment, and technology roadmap.

  17. A six-year retrospective analysis of cut-out risk predictors in cephalomedullary nailing for pertrochanteric fractures: Can the tip-apex distance (TAD) still be considered the best parameter?

    Science.gov (United States)

    Caruso, G; Bonomo, M; Valpiani, G; Salvatori, G; Gildone, A; Lorusso, V; Massari, L

    2017-08-01

    Intramedullary fixation is considered the most stable treatment for pertrochanteric fractures of the proximal femur and cut-out is one of the most frequent mechanical complications. In order to determine the role of clinical variables and radiological parameters in predicting the risk of this complication, we analysed the data pertaining to a group of patients recruited over the course of six years. A total of 571 patients were included in this study, which analysed the incidence of cut-out in relation to several clinical variables: age; gender; the AO Foundation and Orthopaedic Trauma Association classification system (AO/OTA); type of nail; cervical-diaphyseal angle; surgical wait times; anti-osteoporotic medication; complete post-operative weight bearing; and radiological parameters (namely the lag-screw position with respect to the femoral head, the Cleveland system, the tip-apex distance (TAD), and the calcar-referenced tip-apex distance (CalTAD)). The incidence of cut-out across the sample was 5.6%, with a higher incidence in female patients. A significantly higher risk of this complication was correlated with lag-screw tip positioning in the upper part of the femoral head in the anteroposterior radiological view, posterior in the latero-lateral radiological view, and in the Cleveland peripheral zones. The tip-apex distance and the calcar-referenced tip-apex distance were found to be highly significant predictors of the risk of cut-out at cut-offs of 30.7 mm and 37.3 mm, respectively, but the former appeared more reliable than the latter in predicting the occurrence of this complication. The tip-apex distance remains the most accurate predictor of cut-out, which is significantly greater above a cut-off of 30.7 mm. Cite this article: G. Caruso, M. Bonomo, G. Valpiani, G. Salvatori, A. Gildone, V. Lorusso, L. Massari. A six-year retrospective analysis of cut-out risk predictors in cephalomedullary nailing for pertrochanteric fractures: Can the tip-apex distance

  18. A Review Over the Past 15 Years of the Management of the Internal Piriform Apex Sinus Tract of a Branchial Pouch Anomaly and Case Description.

    Science.gov (United States)

    Josephson, Gary D; Black, Kaelan

    2015-12-01

    Literature review of treating the piriform apex sinus tract through microlaryngoscopy and a case description. Fourteen papers were identified in PubMed using the search criteria of piriform sinus fistula, microlaryngoscopic repair, and endoscopy. Institutional Review Board approval was obtained. One hundred forty-five cases including ours were available for review, with 182 procedures. Sixty-two cases were male, 73 female, and 10 genders were not reported. Multiple treatment options were used, including electrocautery, chemocautery, mass excision, fibrin glue, lasers, suture closure, or combination of stated modalities. Of the 182 procedures, 147 procedures were performed endoscopically. There were 37 recurrences (25%). These patients either underwent a repeat endoscopic procedure or an open excision. One hundred and ten (75%) endoscopic procedures were successful. Piriform sinus tract anomalies often present as a mass and recurrent neck infections. This review reveals that treating the internal piriform sinus opening alone can be successful. This procedure has low morbidity, short operative time, and high success. We advocate this approach first with a combined open/laryngoscopic approach for failed cases. To our knowledge, our technique of CO₂laser ablation of the tract followed by suture closure has not been previously described. We believe this to be the first comprehensive review of this topic and the largest series of cases included in a single report. © The Author(s) 2015.

  19. Thrombus Burden of Deep Vein Thrombosis and Its Association with Thromboprophylaxis and D-Dimer Measurement: Insights from the APEX Trial.

    Science.gov (United States)

    Chi, Gerald; Goldhaber, Samuel Z; Hull, Russell D; Hernandez, Adrian F; Kerneis, Mathieu; Al Khalfan, Fahad; Cohen, Alexander T; Harrington, Robert A; Gibson, C Michael

    2017-12-01

    Background The aim of this study was to evaluate the effect of betrixaban on the occurrence of deep vein thrombosis (DVT) and also the extent of thrombus and to assess the association of baseline D-dimer with subsequent thrombus burden. Methods In the APEX trial (ClinicalTrials.gov: NCT01583218), 7,513 acutely ill hospitalized medical patients were randomly assigned to extended-duration betrixaban (35–42 days) or enoxaparin (10 ± 4 days). D-dimer concentration was measured at baseline, and mandatory lower-extremity compression ultrasonography (CUS) was performed at 35 to 42 days. The thrombus burden of DVT was assessed by the number of non-compressible vascular segments in six target proximal veins and compared between treatment groups and D-dimer categories (≥2 × upper limit of normal [ULN] versus thrombus burden (p = 0.012 for any-dose and p = 0.001 for full-dose). Elevated D-dimer at baseline was independently associated with a 2.12-fold increased risk of developing DVT (p thrombus burden was also observed in those with D-dimer ≥ 2 × ULN compared with venous segments with thrombosis at 35 to 42 days compared with enoxaparin. A positive D-dimer was associated with a greater extent of thrombus burden among acutely ill medical patients who developed DVT despite receiving thromboprophylaxis.

  20. The Effect of File Size and Type and Irrigation Solutions on the Accuracy of Electronic Apex Locators: An In Vitro Study on Canine Teeth.

    Science.gov (United States)

    Janeczek, Maciej; Kosior, Piotr; Piesiak-Pańczyszyn, Dagmara; Dudek, Krzysztof; Chrószcz, Aleksander; Czajczyńska-Waszkiewicz, Agnieszka; Kowalczyk-Zając, Małgorzata; Gabren-Syller, Aleksandra; Kirstein, Karol; Skalec, Aleksandra; Bryła, Ewelina; Dobrzyński, Maciej

    2016-01-01

    Measurements of the root canal during endodontic treatment have a significant influence on the course of the therapeutic process as well as on its final result in both human and veterinary medicine. The apical constriction should be the termination point for the preparation and filling of the root canal. This research was conducted with the use of a Septodont kit consisting of a small chamber filled with the examined solution in which a healthy second incisor was placed. The step back method was applied for the root canal preparation and master apical file of 30 was used. The working length was 22 mm. The examination was conducted with the use of steel as well as nickel titanium hand instruments. Different irrigation solutions and two types of apex locators were used. Measurements of the working length of the root canal showed dependence on the size of the instrument. Examinations carried out in various environments showed that analogical measurements were obtained only for sodium hypochlorite solutions. In other environments the measured sections were shortened. Comparative examinations with the use of steel instruments demonstrated insignificant measurement differences. Compared to these results, the measurements in nickel titanium group were characterized by more considerable deviations.

  1. The Effect of File Size and Type and Irrigation Solutions on the Accuracy of Electronic Apex Locators: An In Vitro Study on Canine Teeth

    Directory of Open Access Journals (Sweden)

    Maciej Janeczek

    2016-01-01

    Full Text Available Measurements of the root canal during endodontic treatment have a significant influence on the course of the therapeutic process as well as on its final result in both human and veterinary medicine. The apical constriction should be the termination point for the preparation and filling of the root canal. This research was conducted with the use of a Septodont kit consisting of a small chamber filled with the examined solution in which a healthy second incisor was placed. The step back method was applied for the root canal preparation and master apical file of 30 was used. The working length was 22 mm. The examination was conducted with the use of steel as well as nickel titanium hand instruments. Different irrigation solutions and two types of apex locators were used. Measurements of the working length of the root canal showed dependence on the size of the instrument. Examinations carried out in various environments showed that analogical measurements were obtained only for sodium hypochlorite solutions. In other environments the measured sections were shortened. Comparative examinations with the use of steel instruments demonstrated insignificant measurement differences. Compared to these results, the measurements in nickel titanium group were characterized by more considerable deviations.

  2. Late postoperative analysis of the tip-apex distance (TAD) in pertrochanteric fractures: is there an accommodation of the implant within the bone?

    Science.gov (United States)

    Aihara, Leandro Jun; Nanni, Rafael Augusto; Carvalho, Marina Sousa; Zamboni, Caio; Durigan, Jorge R; Hungria Neto, José S; Mercadante, Marcelo T; Christian, Ralph W; Hungria, José O S

    2017-10-01

    This study measured the tip-apex distance (TAD) values in the immediate postoperative period and following weight-bearing and fracture impaction in patients undergoing osteosynthesis with dynamic hip screw and cephalomedullary nail. To correlate the Baumgaertner index in the immediate postoperative period with values obtained after impaction of the fracture with the accommodation of the cephalic implant in the femoral head. Radiographic TAD measurements were taken with AGFA-VIEW ® of 82 patients with a mean age of 72 years with pertrochanteric fractures who were operated on and the fracture fixed with DHS- Synthes ® , TFN-Synthes ® , or Gamma Nail III-Stryker ® in the immediate postoperative period, and following weight-bearing and fracture impaction (mean 3-8 weeks after surgery). The overall average TAD decreased from 20.3mm to 18.2mm. Regardless of the instability of the fracture, the age of the patient or the implant used, TAD decreased between the immediate postoperative period and following fracture impaction. The osteosynthesis of pertrochanteric fractures was associated with important accommodation of the cephalic implant in the femoral head with decreased TAD values after weight-bearing. © 2017 Elsevier Ltd. All rights reserved.

  3. Physical characterization of the fine particle emissions from commercial aircraft engines during the Aircraft Particle Emissions eXperiment (APEX) 1-3

    Science.gov (United States)

    Kinsey, John S.; Dong, Yuanji; Williams, D. Craig; Logan, Russell

    2010-06-01

    The fine particulate matter (PM) emissions from nine commercial aircraft engine models were determined by plume sampling during the three field campaigns of the Aircraft Particle Emissions Experiment (APEX). Ground-based measurements were made primarily at 30 m behind the engine for PM mass and number concentration, particle size distribution, and total volatile matter using both time-integrated and continuous sampling techniques. The experimental results showed a PM mass emission index (EI) ranging from 10 to 550 mg kg -1 fuel depending on engine type and test parameters as well as a characteristic U-shaped curve of the mass EI with increasing fuel flow for the turbofan engines tested. Also, the Teflon filter sampling indicated that ˜40-80% of the total PM mass on a test-average basis was comprised of volatile matter (sulfur and organics) for most engines sampled. The number EIs, on the other hand, varied from ˜10 15 to 10 17 particles kg -1 fuel with the turbofan engines exhibiting a logarithmic decay with increasing fuel flow. Finally, the particle size distributions of the emissions exhibited a single primary mode that were lognormally distributed with a minor accumulation mode also observed at higher powers for all engines tested. The geometric (number) mean particle diameter ranged from 9.4 to 37 nm and the geometric standard deviation ranged from 1.3 to 2.3 depending on engine type, fuel flow, and test conditions.

  4. The influence of determining the working length with an apex locator on the amount of apically extruded debris following instrumentation with ProTaper Next and HyFlex CM

    Directory of Open Access Journals (Sweden)

    Ersan Çiçek

    2016-01-01

    Full Text Available Aim: The amount of apically extruded debris caused by new nickel-titanium rotary systems after determination of the working length (WL with an apex locator has not been investigated. To compare the amount of apically extruded debris with ProTaper Next (PTN and HyFlex CM systems after determination of WL with/without an apex locator. Materials and Methods: Forty-eight extracted mandibular incisor teeth divided into four groups were used in this study. In Groups 1 and 2, a 10 K-file was progressed until it was just visible at the major apical foramen and WL was recorded as 1 mm short. In Groups 3 and 4, the WL was determined with the Root ZX (sensitivity of 0.1 using a 10 K-file. During the instrumentation, the PTN was used to X2 in groups 1 and 3, and the HyFlex CM was used to 25/.06 in groups 2 and 4. Distilled water was used as an irrigant. Debris was collected in tubes then stored in an incubator at 68°C for 5 days to evaporate the distilled water. The Eppendorf tubes, including the extruded debris, were weighed to obtain final weights. The amount of extruded debris was calculated by subtracting the weight of the empty tube from the weight of the dry tube. Data were analyzed by Kruskal–Wallis and Mann–Whitney U-test. Results: Less apically extruded debris was obtained in Group 3, with a significant difference compared to Group 1 and Group 2 (P < 0.05. Conclusions: The usage of apex locator to determine the WL decreased the amount of apically extruded debris. In addition, PTN caused less apical debris extrusion after determination WL with/without apex locator.

  5. Towards a Generic and Adaptive System-On-Chip Controller for Space Exploration Instrumentation

    Science.gov (United States)

    Iturbe, Xabier; Keymeulen, Didier; Yiu, Patrick; Berisford, Dan; Hand, Kevin; Carlson, Robert; Ozer, Emre

    2015-01-01

    This paper introduces one of the first efforts conducted at NASA’s Jet Propulsion Laboratory (JPL) to develop a generic System-on-Chip (SoC) platform to control science instruments that are proposed for future NASA missions. The SoC platform is named APEX-SoC, where APEX stands for Advanced Processor for space Exploration, and is based on a hybrid Xilinx Zynq that combines an FPGA and an ARM Cortex-A9 dual-core processor on a single chip. The Zynq implements a generic and customizable on-chip infrastructure that can be reused with a variety of instruments, and it has been coupled with a set of off-chip components that are necessary to deal with the different instruments. We have taken JPL’s Compositional InfraRed Imaging Spectrometer (CIRIS), which is proposed for NASA icy moons missions, as a use-case scenario to demonstrate that the entire data processing, control and interface of an instrument can be implemented on a single device using the on-chip infrastructure described in this paper. We show that the performance results achieved in this preliminary version of the instrumentation controller are sufficient to fulfill the science requirements demanded to the CIRIS instrument in future NASA missions, such as Europa.

  6. Geophysical Exploration. New site exploration method

    Energy Technology Data Exchange (ETDEWEB)

    Imai, Tsuneo; Otomo, Hideo; Sakayama, Toshihiko

    1988-07-25

    Geophysical exploration is used for geologic survey to serve purposes in civil engineering. New methods are being developed inside and outside Japan and are used to serve various purposes. This paper discusses recently developed techniques based on the measurement of seismic waves and electric potential. It also explains seismic tomography, radar tomography, and resistivity tomography which are included in the category of geotomography. At present, effort is being made to apply geophysical exploration technology to problems which were considered to be unsuitable for conventional exploration techniques. When such effort proceeds successfully, it is necessary to develop technology for presenting results quickly and exploration equipment which can work in various conditions. (10 figs, 15 refs)

  7. Apex pruning in pumpkin for fruit and seed production=Poda apical para produção de frutos e sementes de abóbora

    Directory of Open Access Journals (Sweden)

    Marina Toledo Rodrigues Claudio

    2014-08-01

    Full Text Available The tip pruning stimulates the emission of lateral shoots, thus can produce higher number of flowers, fruits and seeds. This work aimed to evaluate the effect of apex pruning on fruit and seed production in pumpkin. The treatments consisted of plants without pruning, with pruning in the sixth, eighth and tenth node of main stem. The experimental design was a randomized block, with six replications. It was studied a line of pumpkin of the Germplasm Bank of the Universidade Estadual Paulista/Faculdade de Ciências Agronômicas. The characteristics evaluated were: number of branches per plant and fruit position in branches of the plant production (number and weight of fruits per plant, fruit yield, fruit average weight, fruit length and diameter, seed weight per fruit, seed yield and quality (germination test, first count, thousand seed weight, emergence, speed of emergence and accelerated aging. There was a significant difference only for number of secondary branches per plant and thousand seed weight, with larger values for plants that have not been pruned. It was obtained high average of germination (94% and good fruit (16.9 t ha-1 and seed (148 kg ha-1 yield. The apex pruning does not influence the production of fruits and seeds, as well as the physiological seed quality in pumpkin =A poda apical estimula a emissão de brotos laterais, com isso pode haver maior formação de flores e frutos e, consequentemente, maior número de sementes. Diante disso, objetivou-se avaliar o efeito da poda da haste principal para a produção de frutos e sementes de abóbora. Os tratamentos foram constituídos de plantas sem poda, com poda no sexto, oitavo e décimo nó da haste principal. O delineamento experimental foi em blocos casualizados, com seis repetições. Foi utilizada a linhagem de abóbora do tipo braquítica do Banco de Germoplasma da Universidade Estadual Paulista/Faculdade de Ciências Agronômicas. Foram avaliadas as seguintes caracter

  8. Exploration and Mining Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2002-09-01

    This Exploration and Mining Technology Roadmap represents the third roadmap for the Mining Industry of the Future. It is based upon the results of the Exploration and Mining Roadmap Workshop held May 10 ñ 11, 2001.

  9. TIP APEX DISTANCE OF INTRAMEDULLARY DEVICES AS A PREDICTOR OF CUT-OUT FAILURE IN TREATMENT OF PERITROCHANTERIC ELDERLY HIP FRACTURES

    Directory of Open Access Journals (Sweden)

    Purushotham K

    2017-02-01

    Full Text Available BACKGROUND A Tip-Apex Distance (TAD of greater than 25 mm has been shown to be an accurate predictor of lag screw cut-out when Sliding Hip Screws (SHS are used to treat Peritrochanteric (PT fractures. The purpose of this study was to determine, which factors, including TAD correlated with successful clinical outcomes of PT hip fractures surgically treated with intramedullary devices. MATERIALS AND METHODS A total of 72 patients were included in this retrospective study. TAD values were radiographically analysed at a mean follow up of 13 months. This was correlated with limited functional status and rate of revision for implant failure or inability to achieve fracture union. Only 62 patients had adequate follow up to fracture union or definitive failure. RESULTS There were 36 intertrochanteric fractures and 26 subtrochanteric fractures. Overall, 5 patients (9.8% went on to experience lag screw cut out. The average TAD of patients who did not cut-out was 18 mm compared to 38 mm for those who did (p=0.012. All patients who cut-out had IT fractures. CONCLUSION The percentage of cut-outs correlated clinically to both the severity of IT fractures and the TAD. Using a cut-off of 25 mm, there was a statistically significant difference in the incidence of lag screw cut-out (p<0.001. As in sliding hip screw, surgeons should strive for a TAD less than 25 mm when using IM devices in the treatment of PT hip fractures to help avoid lag screw cut-out.

  10. Evaluation of Two New Electronic Apex-Locator-Controlled Handpieces Using a NiTi Rotary File: An In Vitro Study.

    Directory of Open Access Journals (Sweden)

    Kiumarz Nazarimoghadam

    2013-12-01

    Full Text Available The aim of this in-vitro study was to compare the accuracy of two new electronic apex-locator controlled handpieces (EALHs using the first rotary Mtwo file while rotating in the canal.A total of 36 extracted mandibular molar teeth were selected. The lengths of the mesio-buccal canals to the major foramina were measured directly using a size 10 K-file introduced in the canal until the tip was visible under a loupe and then 0.5 mm was subtracted from the recorded lengths as the actual working lengths (AWLs. Subsequently, the teeth were randomly assigned to two groups and embedded in an alginate model. Auto-stop function of the EALHs was preset at "0.5" mark and then electrical working lengths (EWLs in groups 1 and 2 were recorded by VDW GOLD and Dentaport ZX, respectively. Analysis of variance (ANOVA, 1-way and Tukey pairwise multiple comparison intervals (0.05 were used to compare the accuracy of the two electronic devices.For VDW GOLD, 61.1% of the measurements were within ±0.5 mm and 88.9% were within ±1 mm of the AWL. For Dentaport ZX, 88.9% of the measurements were within ±0.5 mm and 94.4% were within ±1mm of the AWL. There was no significant difference between AWLs and EWLs (p=0.466 for Dentaport ZX and p=0.283 for VDW Gold and between the accuracy of the two devices in determining the EWL (p=0.8.Both Dentaport ZX and VDW Gold were suitable for determining working length using a rotary file. To avoid over instrumenting the canal, we recommend setting the devices to automatically stop or reverse the rotary file at 1 mm level.

  11. Continuous, high-resolution biospeckle imaging reveals a discrete zone of activity at the root apex that responds to contact with obstacles.

    Science.gov (United States)

    Ribeiro, K M; Barreto, B; Pasqual, M; White, P J; Braga, R A; Dupuy, L X

    2014-02-01

    Shining a laser onto biological material produces light speckles termed biospeckles. Patterns of biospeckle activity reflect changes in cell biochemistry, developmental processes and responses to the environment. The aim of this work was to develop methods to investigate the biospeckle activity in roots and to characterize the distribution of its intensity and response to thigmostimuli. Biospeckle activity in roots of Zea mays, and also Jatropha curcas and Citrus limonia, was imaged live and in situ using a portable laser and a digital microscope with a spatial resolution of 10 μm per pixel and the ability to capture images every 0.080 s. A procedure incorporating a Fujii algorithm, image restoration using median and Gaussian filters, image segmentation using maximum-entropy threshold methods and the extraction of features using a tracing algorithm followed by spline fitting were developed to obtain quantitative information from images of biospeckle activity. A wavelet transform algorithm was used for spectral decomposition of biospeckle activity and generalized additive models were used to attribute statistical significance to changes in patterns of biospeckle activity. The intensity of biospeckle activity was greatest close to the root apex. Higher frequencies (3-6 Hz) contributed most to the total intensity of biospeckle activity. When a root encountered an obstacle, the intensity of biospeckle activity decreased abruptly throughout the root system. The response became attenuated with repeated thigmostimuli. The data suggest that at least one component of root biospeckle activity resulted from a biological process, which is located in the zone of cell division and responds to thigmostimuli. However, neither individual cell division events nor root elongation is likely to be responsible for the patterns of biospeckle activity.

  12. Anatomical study of the relationship of impacted mandibular third molar root apex to inferior alveolar canal in Kurdistan population using orthopantomogram

    Directory of Open Access Journals (Sweden)

    Fedil Andraws Yalda

    2017-12-01

    Full Text Available Background and objective: Extraction of an impacted mandibular third lower molar tooth is one of the common surgical procedures that may lead to the damage of inferior alveolar nerve due to roots proximity to the mandibular canal. This study aimed to know the relative relationship and proximity of the mandibular third molar roots to the inferior alveolar canal in relation to gender, age, depth of impaction, relation with ramus, and type of angulation of the impacted tooth in Kurdistan population. Methods: A sample of 366 digital panoramic radiographs of patients with impacted mandibular third molar was studied. Panoramic radiographic signs images were evaluated for the presence of root contact with the superior border of the mandibular canal, darkening of the roots apex, deflected roots, narrow root, superimposition of the canal, interruption of the white line, diversion of the inferior alveolar canal, and narrowing of the inferior alveolar canal. The depths of impaction, relation with ramus, and type of angulation were also studied. Results: Significant relation of the proximity of the mandibular third molar roots to the inferior alveolar canal with the gender (P = 0.001 and age (P <0.001 were seen. A significant relation of the proximity of the mandibular third molar roots to the inferior alveolar canal with the depth of impaction (P <0.001, relation with the ramus (P =0.004, and angulation of impaction were also seen (P <0.001. Conclusion: Significant relation of the proximity of the mandibular third molar roots to the inferior alveolar canal with gender, age, depth of impaction, relation with the ramus, and angulation of impaction were seen.

  13. A New Perspective on the Foraging Ecology of Apex Predators in the California Current: Results from a Fully Coupled Ecosystem Model

    Science.gov (United States)

    Fiechter, J.; Huckstadt, L. A.; Rose, K.; Costa, D. P.; Curchitser, E. N.; Hedstrom, K.; Edwards, C. A.; Moore, A. M.

    2016-02-01

    Results from a fully coupled end-to-end ecosystem model for the California Current Large Marine Ecosystem are used to describe the impact of environmental variability on the foraging ecology of its most abundant apex predator, California sea lions (Zalophus californianus). The ecosystem model consists of a biogeochemical submodel embedded in a regional ocean circulation submodel, and both coupled with a multi-species individual-based submodel for forage fish (sardine and anchovy) and California sea lions. For sea lions, bioenergetics and behavioral attributes are specified using available TOPP (Tagging Of Pacific Predators) data on their foraging patterns and diet in the California Current. Sardine and anchovy are explicitly included in the model as they represent important prey sources for California sea lions and exhibit significant interannual and decadal variability in population abundances. Output from a 20-year run (1989-2008) of the model demonstrates how different physical and biological processes control habitat utilization and foraging success of California sea lions on interannual time scales. A principal component analysis of sea lion foraging patterns indicates that the first mode of variability is alongshore and tied to sardine availability, while the second mode is cross-shore and associated with coastal upwelling intensity (a behavior consistent with male sea lion tracking data collected in 2004 vs. 2005). The results also illustrate how variability in environmental conditions and forage fish distribution affects sea lions feeding success. While specifically focusing on the foraging ecology of sea lions, our modeling framework has the ability to provide new and unique perspectives on trophic interactions in the California Current, or other regions where similar end-to-end ecosystem models may be implemented.

  14. Asteroid exploration and utilization: The Hawking explorer

    Science.gov (United States)

    Carlson, Alan; Date, Medha; Duarte, Manny; Erian, Neil; Gafka, George; Kappler, Peter; Patano, Scott; Perez, Martin; Ponce, Edgar; Radovich, Brian

    1991-01-01

    The Earth is nearing depletion of its natural resources at a time when human beings are rapidly expanding the frontiers of space. The resources which may exist on asteroids could have enormous potential for aiding and enhancing human space exploration as well as life on Earth. With the possibly limitless opportunities that exist, it is clear that asteroids are the next step for human existence in space. This report comprises the efforts of NEW WORLDS, Inc. to develop a comprehensive design for an asteroid exploration/sample return mission. This mission is a precursor to proof-of-concept missions that will investigate the validity of mining and materials processing on an asteroid. Project STONER (Systematic Transfer of Near Earth Resources) is based on two utilization scenarios: (1) moving an asteroid to an advantageous location for use by Earth; and (2) mining an asteroids and transporting raw materials back to Earth. The asteroid explorer/sample return mission is designed in the context of both scenarios and is the first phase of a long range plane for humans to utilize asteroid resources. The report concentrates specifically on the selection of the most promising asteroids for exploration and the development of an exploration scenario. Future utilization as well as subsystem requirements of an asteroid sample return probe are also addressed.

  15. Modelling oil exploration

    International Nuclear Information System (INIS)

    Padilla, V.R.

    1992-01-01

    The analysis of oil exploration models in this paper is developed in four parts. The way in which exploration has been dealt with in oil supply models is first described. Five recent models are then looked at, paying particular attention to the explanatory variables used when modelling exploration activities. This is followed by a discussion of the factors which have been shown by several empirical studies to determine exploration in less developed countries. Finally, the interdependence between institutional factors, oil prices and exploration effort is analysed with a view to drawing conclusions for modelling in the future. (UK)

  16. Marine Mineral Exploration

    DEFF Research Database (Denmark)

    in EEZ areas are fairly unknown; many areas need detailed mapping and mineral exploration, and the majority of coastal or island states with large EEZ areas have little experience in exploration for marine hard minerals. This book describes the systematic steps in marine mineral exploration....... Such exploration requires knowledge of mineral deposits and models of their formation, of geophysical and geochemical exploration methods, and of data evaluation and interpretation methods. These topics are described in detail by an international group of authors. A short description is also given of marine...

  17. International exploration by independent

    International Nuclear Information System (INIS)

    Bertragne, R.G.

    1992-01-01

    Recent industry trends indicate that the smaller U.S. independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. Foreign finding costs per barrel usually are accepted to be substantially lower than domestic costs because of the large reserve potential of international plays. To get involved in overseas exploration, however, requires the explorationist to adapt to different cultural, financial, legal, operational, and political conditions. Generally, foreign exploration proceeds at a slower pace than domestic exploration because concessions are granted by a country's government, or are explored in partnership with a national oil company. First, the explorationist must prepare a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company; next, is an ongoing evaluation of quality prospects in various sedimentary basins, and careful planning and conduct of the operations. To successfully explore overseas also requires the presence of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work. Ideally, these team members will have had a considerable amount of on-site experience in various countries and climates. Independents best suited for foreign expansion are those who have been financially successful in domestic exploration. When properly approached, foreign exploration is well within the reach of smaller U.S. independents, and presents essentially no greater risk than domestic exploration; however, the reward can be much larger and can catapult the company into the 'big leagues.'

  18. Geochemical exploration for uranium

    International Nuclear Information System (INIS)

    1988-01-01

    This Technical Report is designed mainly to introduce the methods and techniques of uranium geochemical exploration to exploration geologists who may not have had experience with geochemical exploration methods in their uranium programmes. The methods presented have been widely used in the uranium exploration industry for more than two decades. The intention has not been to produce an exhaustive, detailed manual, although detailed instructions are given for a field and laboratory data recording scheme and a satisfactory analytical method for the geochemical determination of uranium. Rather, the intention has been to introduce the concepts and methods of uranium exploration geochemistry in sufficient detail to guide the user in their effective use. Readers are advised to consult general references on geochemical exploration to increase their understanding of geochemical techniques for uranium

  19. Visual explorer facilitator's guide

    CERN Document Server

    Palus, Charles J

    2010-01-01

    Grounded in research and practice, the Visual Explorer™ Facilitator's Guide provides a method for supporting collaborative, creative conversations about complex issues through the power of images. The guide is available as a component in the Visual Explorer Facilitator's Letter-sized Set, Visual Explorer Facilitator's Post card-sized Set, Visual Explorer Playing Card-sized Set, and is also available as a stand-alone title for purchase to assist multiple tool users in an organization.

  20. DISCOVERY OF BROAD MOLECULAR LINES AND OF SHOCKED MOLECULAR HYDROGEN FROM THE SUPERNOVA REMNANT G357.7+0.3: HHSMT, APEX, SPITZER , AND SOFIA OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Rho, J. [SETI Institute, 189 N. Bernardo Ave., Mountain View, CA 94043 (United States); Hewitt, J. W. [CRESST/University of Maryland, Baltimore County, Baltimore, MD 21250 and NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Bieging, J. [Steward Observatory, The University of Arizona, Tucson AZ 85721 (United States); Reach, W. T. [Universities Space Research Association, SOFIA Science Center, NASA Ames Research Center, MS 232, Moffett Field, CA 94034 (United States); Andersen, M. [Gemini Observatory, Casilla 603, La Serena (Chile); Güsten, R., E-mail: jrho@seti.org, E-mail: john.w.hewitt@unf.edu, E-mail: jbieging@as.arizona.edu, E-mail: wreach@sofia.usra.edu, E-mail: manderse@gemini.edu, E-mail: guesten@mpifr-bonn.mpg.de [Max Planck Institut für Radioastronomie, Auf dem Hugel 69, D-53121 Bonn (Germany)

    2017-01-01

    We report a discovery of shocked gas from the supernova remnant (SNR) G357.7+0.3. Our millimeter and submillimeter observations reveal broad molecular lines of CO(2-1), CO(3-2), CO(4-3), {sup 13}CO (2-1), and {sup 13}CO (3-2), HCO{sup +}, and HCN using the Heinrich Hertz Submillimeter Telescope, the Arizona 12 m Telescope, APEX, and the MOPRA Telescope. The widths of the broad lines are 15–30 km s{sup −1}, and the detection of such broad lines is unambiguous, dynamic evidence showing that the SNR G357.7+0.3 is interacting with molecular clouds. The broad lines appear in extended regions (>4.′5 × 5′). We also present the detection of shocked H{sub 2} emission in the mid-infrared but lacking ionic lines using Spitzer /IRS observations to map a few-arcminute area. The H{sub 2} excitation diagram shows a best fit with a two-temperature local thermal equilibrium model with the temperatures of ∼200 and 660 K. We observed [C ii] at 158 μ m and high- J CO(11-10) with the German Receiver for Astronomy at Terahertz Frequencies (GREAT) on the Stratospheric Observatory for Infrared Astronomy. The GREAT spectrum of [C ii], a 3 σ detection, shows a broad line profile with a width of 15.7 km{sup −1} that is similar to those of broad CO molecular lines. The line width of [C ii] implies that ionic lines can come from a low-velocity C-shock. Comparison of H{sub 2} emission with shock models shows that a combination of two C-shock models is favored over a combination of C- and J-shocks or a single shock. We estimate the CO density, column density, and temperature using a RADEX model. The best-fit model with n (H{sub 2}) = 1.7 × 10{sup 4} cm{sup −3}, N(CO) = 5.6 × 10{sup 16} cm{sup −2}, and T  = 75 K can reproduce the observed millimeter CO brightnesses.

  1. A comparative evaluation of working length with digital radiography and third generation apex locator (ProPex in the presence of various intracanal irrigants: An in vivo/ex vivo study

    Directory of Open Access Journals (Sweden)

    Irfana Khursheed

    2014-01-01

    Full Text Available Background: Accurate working length determination is a pre-requisite for a successful endodontic treatment. Even with improved systems of working length measurement, different readings may be recorded in different electrolytes present in the canal. The purpose of this in vivo/ex vivo comparative study was to determine the accuracy in measuring the working length of root canal using Direct Digital Radiographic Method (Radiovisiography or RVG and ProPex electronic apex locator in the presence of three different irrigating solutions: 0.9% normal saline, 2% chlorhexidine, 3% NaOCl solutions. Materials and Methods: Forty single-rooted human teeth scheduled for extraction with mature apices were selected for this study. Measurements were performed by using RVG and ProPex in the presence of irrigating solutions. After extraction of the teeth, light microscope was used to confirm visually the relationship of the tip of the endodontic file to the apical foramen, and actual lengths were determined by reducing 0.5 mm from this length. The statistical analysis was performed by one-way ANOVA test and Tukey-HSD post hoc procedure. P < 0.05 was considered as significant. Results: No significant difference was found between overall mean electronic working length and digital radiographic length; however, prediction error (P < 0.05 was significant with respect to different irrigants. Among the irrigating solutions, chlorhexidine gluconate had the smallest distance to the actual lengths, whereas NaOCl had the greatest. Conclusion: Electronic apex locator ProPex yielded best result in the presence of chlorhexidine, whereas the largest error was demonstrated with NaOCl indicating that higher electroconductive irrigating solutions affect the precision of multi-frequency apex locators.

  2. AMPK agonist AICAR delays the initial decline in lifetime-apex V̇o2 peak, while voluntary wheel running fails to delay its initial decline in female rats.

    Science.gov (United States)

    Toedebusch, Ryan G; Ruegsegger, Gregory N; Braselton, Joshua F; Heese, Alexander J; Hofheins, John C; Childs, Tom E; Thyfault, John P; Booth, Frank W

    2016-02-01

    There has never been an outcome measure for human health more important than peak oxygen consumption (V̇o2 peak), yet little is known regarding the molecular triggers for its lifetime decline with aging. We examined the ability of physical activity or 5 wk of 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) administration to delay the initial aging-induced decline in lifetime-apex V̇o2 peak and potential underlying molecular mechanisms. Experiment 1 consisted of female rats with (RUN) and without (NO RUN) running wheels, while experiment 2 consisted of female nonrunning rats getting the AMPK agonist AICAR (0.5 mg/g/day) subcutaneously for 5 wk beginning at 17 wk of age. All rats underwent frequent, weekly or biweekly V̇o2 peak tests beginning at 10 wk of age. In experiment 1, lifetime-apex V̇o2 peak occurred at 19 wk of age in both RUN and NO RUN and decreased thereafter. V̇o2 peak measured across experiment 1 was ∼25% higher in RUN than in NO RUN. In experiment 2, AICAR delayed the chronological age observed in experiment 1 by 1 wk, from 19 wk to 20 wk of age. RUN and NO RUN showed different skeletal muscle transcriptomic profiles both pre- and postapex. Additionally, growth and development pathways are differentially regulated between RUN and NO RUN. Angiomotin mRNA was downregulated postapex in RUN and NO RUN. Furthermore, strong significant correlations to V̇o2 peak and trends for decreased protein concentration supports angiomotin's potential importance in our model. Contrary to our primary hypothesis, wheel running was not sufficient to delay the chronological age of lifetime-apex V̇o2 peak decline, whereas AICAR delayed it 1 wk. Copyright © 2016 the American Physiological Society.

  3. Evidence of universal inverse-third power law for the shielding-induced fractional decrease in apex field enhancement factor at large spacings: a response via accurate Laplace-type calculations

    Science.gov (United States)

    de Assis, Thiago A.; Dall’Agnol, Fernando F.

    2018-05-01

    Numerical simulations are important when assessing the many characteristics of field emission related phenomena. In small simulation domains, the electrostatic effect from the boundaries is known to influence the calculated apex field enhancement factor (FEF) of the emitter, but no established dependence has been reported at present. In this work, we report the dependence of the lateral size, L, and the height, H, of the simulation domain on the apex-FEF of a single conducting ellipsoidal emitter. Firstly, we analyze the error, ε, in the calculation of the apex-FEF as a function of H and L. Importantly, our results show that the effects of H and L on ε are scale invariant, allowing one to predict ε for ratios L/h and H/h, where h is the height of the emitter. Next, we analyze the fractional change of the apex-FEF, δ, from a single emitter, , and a pair, . We show that small relative errors in (i.e. ), due to the finite domain size, are sufficient to alter the functional dependence , where c is the distance from the emitters in the pair. We show that obeys a recently proposed power law decay (Forbes 2016 J. Appl. Phys. 120 054302), at sufficiently large distances in the limit of infinite domain size (, say), which is not observed when using a long time established exponential decay (Bonard et al 2001 Adv. Mater. 13 184) or a more sophisticated fitting formula proposed recently by Harris et al (2015 AIP Adv. 5 087182). We show that the inverse-third power law functional dependence is respected for various systems like infinity arrays and small clusters of emitters with different shapes. Thus, , with m  =  3, is suggested to be a universal signature of the charge-blunting effect in small clusters or arrays, at sufficient large distances between emitters with any shape. These results improve the physical understanding of the field electron emission theory to accurately characterize emitters in small clusters or arrays.

  4. Uranium exploration in Ecuador

    International Nuclear Information System (INIS)

    Severne, B.; Penaherrera, P.F.; Fiallos, V.S.

    1981-01-01

    The 600-km segment of the Andean Cordillera in Ecuador includes zones that can be correlated, geologically, with uranium districts elsewhere in the Andes. It is believed that these essentially unexplored zones have the potential for economic uranium mineralization. Exploration activity to date has been limited, although it has involved both geochemical and radiometric techniques to evaluate geological concepts. Minor uranium occurrences (with chemical analyses up to 100 ppm) have been encountered, which provide further incentive to commence large-scale systematic exploration. It is recognized that a very large exploration budget and considerable technical expertise will be required to ensure exploration success. Consequently, participation by groups of proven capability from other countries will be sought for Ecuador's national exploration programme. (author)

  5. International exploration by independents

    International Nuclear Information System (INIS)

    Bertagne, R.G.

    1991-01-01

    Recent industry trends indicate that the smaller US independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. It is usually accepted that foreign finding costs per barrel are substantially lower than domestic because of the large reserve potential of international plays. To get involved overseas requires, however, an adaptation to different cultural, financial, legal, operational, and political conditions. Generally foreign exploration proceeds at a slower pace than domestic because concessions are granted by the government, or are explored in partnership with the national oil company. First, a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company, must be prepared; it must be followed by an ongoing evaluation of quality prospects in various sedimentary basins, and a careful planning and conduct of the operations. To successfully explore overseas also requires the presence on the team of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work, having had a considerable amount of onsite experience in various geographical and climatic environments. Independents that are best suited for foreign expansion are those that have been financially successful domestically, and have a good discovery track record. When properly approached foreign exploration is well within the reach of smaller US independents and presents essentially no greater risk than domestic exploration; the reward, however, can be much larger and can catapult the company into the big leagues

  6. Exploration: A misunderstood business

    International Nuclear Information System (INIS)

    Lohrenz, J.

    1991-01-01

    The business of exploration is persistently misunderstand. Why? Misunderstandings persist and even pervade educated, sophisticated, and obviously capable business practitioners and savants of an array of disciplines - finance, economics, and the management sciences. Routine and appropriate assumptions that apply for most businesses invoke nonsense applied to exploration, a unique business. The uniqueness of exploration, unrecognized, sustains the misunderstandings. The authors will not here obliterate these obdurate misunderstandings with some revelation. They show, however, how the misunderstandings naturally arise among those who certainly are not used to being naive

  7. Arts of urban exploration

    DEFF Research Database (Denmark)

    Pinder, David

    2005-01-01

    to the city’ and ‘writing the city’. Through addressing recent cases of psychogeographical experimentation in terms of these themes, the paper raises broad questions about artistic practices and urban exploration to introduce this theme issue on ‘Arts of urban exploration’ and to lead into the specific......This paper addresses ways in which artists and cultural practitioners have recently been using forms of urban exploration as a means of engaging with, and intervening in, cities. It takes its cues from recent events on the streets of New York that involved exploring urban spaces through artistic...

  8. MBN Explorer Users' Guide

    DEFF Research Database (Denmark)

    Solov'yov, Ilia A.; Sushko, Gennady; Solov'yov, Andrey V.

    The MBN Explorer Users' Guide describes how to install and to run MBN Explorer, the software package for advanced multiscale simulations of complex molecular structure and dynamics. This guide includes the description of the main features and the algorithms of the program, the manual how to use...... simulations of structure and dynamics of a broad range of systems with the sizes from the atomic up to the mesoscopic scales. MBN Explorer is being developed and distributed by MBN Research Center, www.mbnresearch.com, which organises hands-on tutorials for the software, user's workshops and conferences....

  9. Avionics Architecture for Exploration

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of the AES Avionics Architectures for Exploration (AAE) project is to develop a reference architecture that is based on standards and that can be scaled and...

  10. Titanic: A Statistical Exploration.

    Science.gov (United States)

    Takis, Sandra L.

    1999-01-01

    Uses the available data about the Titanic's passengers to interest students in exploring categorical data and the chi-square distribution. Describes activities incorporated into a statistics class and gives additional resources for collecting information about the Titanic. (ASK)

  11. Exploration Augmentation Module Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Exploration Augmentation Module (EAM) project goal is to design and deliver a flight module that is to be deployed to Earth-Lunar Distant Retrograde Orbit (DRO)....

  12. Foreign Aid Explorer)

    Data.gov (United States)

    US Agency for International Development — The Foreign Aid Explorer shows the multi-dimensional picture of U.S. foreign assistance through a highly visual and interactive website. The website makes it easy...

  13. Brazilian uranium exploration program

    International Nuclear Information System (INIS)

    Marques, J.P.M.

    1981-01-01

    General information on Brazilian Uranium Exploration Program, are presented. The mineralization processes of uranium depoits are described and the economic power of Brazil uranium reserves is evaluated. (M.C.K.) [pt

  14. Exploring Vietnam's oil potential

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    A brief review is given of the oil production potential in Vietnam. Since Since 1987, the country has been open to foreign investment in offshore exploration but has suffered from a US embargo on trade and economic ties. Nevertheless some exploration has occurred and twenty production sharing contracts with international oil companies has been signed. To date most of the finds have been non-commercial but optimism remains high. (U.K.)

  15. Developing the MD Explorer

    Science.gov (United States)

    Howie, Philip V.

    1993-04-01

    The MD Explorer is an eight-seat twin-turbine engine helicopter which is being developed using integrated product definition (IPD) team methodology. New techniques include NOTAR antitorque system for directional control, a composite fuselage, an all-composite bearingless main rotor, and digital cockpit displays. Three-dimensional CAD models are the basis of the entire Explorer design. Solid models provide vendor with design clarification, removing much of the normal drawing interpretation errors.

  16. Exploration Laboratory Analysis

    Science.gov (United States)

    Krihak, M.; Ronzano, K.; Shaw, T.

    2016-01-01

    The Exploration Laboratory Analysis (ELA) project supports the Exploration Medical Capability (ExMC) risk to minimize or reduce the risk of adverse health outcomes and decrements in performance due to in-flight medical capabilities on human exploration missions. To mitigate this risk, the availability of inflight laboratory analysis instrumentation has been identified as an essential capability for manned exploration missions. Since a single, compact space-ready laboratory analysis capability to perform all exploration clinical measurements is not commercially available, the ELA project objective is to demonstrate the feasibility of emerging operational and analytical capability as a biomedical diagnostics precursor to long duration manned exploration missions. The initial step towards ground and flight demonstrations in fiscal year (FY) 2015 was the down selection of platform technologies for demonstrations in the space environment. The technologies selected included two Small Business Innovation Research (SBIR) performers: DNA Medicine Institutes rHEALTH X and Intelligent Optical Systems later flow assays combined with Holomics smartphone analyzer. The selection of these technologies were based on their compact size, breadth of analytical capability and favorable ability to process fluids in a space environment, among several factors. These two technologies will be advanced to meet ground and flight demonstration success criteria and requirements that will be finalized in FY16. Also, the down selected performers will continue the technology development phase towards meeting prototype deliverables in either late 2016 or 2017.

  17. International exploration by independents

    International Nuclear Information System (INIS)

    Bertagne, R.G.

    1992-01-01

    Recent industry trends indicate that the smaller U.S. independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. The problems of communications and logistics caused by different cultures and by geographic distances must be carefully evaluated. A mid-term to long-term strategy tailored to the goals and the financial capabilities of the company should be prepared and followed by a careful planning of the operations. This paper addresses some aspects of foreign exploration that should be considered before an independent venture into the foreign field. It also provides some guidelines for conducting successful overseas operations. When properly assessed, foreign exploration is well within the reach of smaller U.S. independents and presents no greater risk than domestic exploration; the rewards, however, can be much larger. Furthermore, the Oil and Gas Journal surveys of the 300 largest U.S. petroleum companies show that companies with a consistent foreign exploration policy have fared better financially during difficult times

  18. Dealing with exploration uncertainties

    International Nuclear Information System (INIS)

    Capen, E.

    1992-01-01

    Exploration for oil and gas should fulfill the most adventurous in their quest for excitement and surprise. This paper tries to cover that tall order. The authors will touch on the magnitude of the uncertainty (which is far greater than in most other businesses), the effects of not knowing target sizes very well, how to build uncertainty into analyses naturally, how to tie reserves and chance estimates to economics, and how to look at the portfolio effect of an exploration program. With no apologies, the authors will be using a different language for some readers - the language of uncertainty, which means probability and statistics. These tools allow one to combine largely subjective exploration information with the more analytical data from the engineering and economic side

  19. Exploring ambiguous realms

    DEFF Research Database (Denmark)

    Clemensen, Nana

    2016-01-01

    In Hang'ombe Village in rural Zambia, the relative lack of physical boundaries between the activities of family members allow children to observe the actions and discussions of adults on close hand, exposing them to the ambiguities of daily life. Children explore these ambiguities in their intera...... in their interactions, testing social roles and conventions. This article explores the vigilance and creative agency displayed by Hang'ombe children, in an environment spurring their acquisition of distinct social and discursive skills.......In Hang'ombe Village in rural Zambia, the relative lack of physical boundaries between the activities of family members allow children to observe the actions and discussions of adults on close hand, exposing them to the ambiguities of daily life. Children explore these ambiguities...

  20. Exploring the solar system

    CERN Document Server

    Bond, Peter

    2012-01-01

    The exploration of our solar system is one of humanity's greatest scientific achievements. The last fifty years in particular have seen huge steps forward in our understanding of the planets, the sun, and other objects in the solar system. Whilst planetary science is now a mature discipline - involving geoscientists, astronomers, physicists, and others - many profound mysteries remain, and there is indeed still the tantalizing possibility that we may find evidence of life on another planet in our system.Drawing upon the latest results from the second golden age of Solar System exploration, aut

  1. Optimal exploration target zones

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2008-09-01

    Full Text Available -of-evidence (WofE) method logistic regression canonical favorability analysis neural networks evidential belief functions Optimal Exploration Target Zones Debba, Carranza, Stein, van der Meer Introduction to Remote Sensing Background and Objective of the study... for the following equation: n∑ i=r ( n i ) pi(1− p)n−i = 0.95 . (1) Optimal Exploration Target Zones Debba, Carranza, Stein, van der Meer Introduction to Remote Sensing Background and Objective of the study Methodology Results METHODS (cont. . . ): FITNESS FUNCTION...

  2. Exploring Racism through Photography

    Science.gov (United States)

    Fey, Cass; Shin, Ryan; Cinquemani, Shana; Marino, Catherine

    2010-01-01

    Photography is a powerful medium with which to explore social issues and concerns through the intersection of artistic form and concept. Through the discussions of images and suggested activities, students will understand various ways photographers have documented and addressed racism and discrimination. This Instructional Resource presents a…

  3. Exploring pedestrian movement patterns

    NARCIS (Netherlands)

    Orellana, D.A.

    2012-01-01

    The main objective of this thesis is to develop an approach for exploring, analysing and interpreting movement patterns of pedestrians interacting with the environment. This objective is broken down in sub-objectives related to four research questions. A case study of the movement of visitors in a

  4. Exploring Sound with Insects

    Science.gov (United States)

    Robertson, Laura; Meyer, John R.

    2010-01-01

    Differences in insect morphology and movement during singing provide a fascinating opportunity for students to investigate insects while learning about the characteristics of sound. In the activities described here, students use a free online computer software program to explore the songs of the major singing insects and experiment with making…

  5. Geophysics in uranium exploration

    International Nuclear Information System (INIS)

    Darnley, A.G.

    1975-01-01

    There are no revolutionary new methods of uranium exploration on the horizon. Continuing improvements in existing methods and types of instrumentation are to be expected, but the main scope of improvement will hinge upon using the best of the available methods more meticulously and systematically, and paying more attention to the analysis of data. (author)

  6. Exploring heroin consumption

    NARCIS (Netherlands)

    Trautmann, Franz; Frijns, Tom

    2013-01-01

    In this report we explore some aspects of heroin consumption, using the data we collected through the face-to-face interviews and comparing our findings with data from other research and monitoring sources. We focus on Italy, the Netherlands and England, the three sample Member States where we have

  7. Antarctica: Discovery & Exploration.

    Science.gov (United States)

    Gascoigne, Toss; Collett, Peter

    An examination of Antarctica, from the first sightings to the heroic explorations of the late 18th and early 19th centuries to modern-day research, is presented in this book. Twelve chapters are as follows: (1) The search begins; (2) Whalers and sealers: bites and nibbles; (3) The new continent: first sight; (4) Wintering: the first party; (5)…

  8. Exploring Project Management Education

    NARCIS (Netherlands)

    Steven Nijhuis

    2017-01-01

    From the article: "The object of this paper is to explore the actual practice in project management education in the Netherlands and compare it to reference institutions and recent literature. A little over 40% of the Higher Education institutions in the Netherlands mentions PM education in

  9. Exploring processes and deviations

    NARCIS (Netherlands)

    Leemans, S.J.J.; Fahland, D.; Aalst, van der W.M.P.; Fournier, F.; Mendling, J.

    2015-01-01

    In process mining, one of the main challenges is to discover a process model, while balancing several quality criteria. This often requires repeatedly setting parameters, discovering a map and evaluating it, which we refer to as process exploration. Commercial process mining tools like Disco,

  10. Beyond frontier exploration

    NARCIS (Netherlands)

    Visser, A.; Ji, X.; van Ittersum, M.; González Jaime, L.A.; Stancu, L.A.

    2008-01-01

    This article investigates the prerequisites for a global exploration strategy in an unknown environment on a virtual disaster site. Assume that a robot equipped with a laser range scanner can build a detailed map of a previous unknown environment. The remaining question is how to use this

  11. Domestic uranium exploration activities

    International Nuclear Information System (INIS)

    Chenoweth, W.L.

    1980-01-01

    Uranium exploration in the United States reached its alltime high in 1978 when the chief exploration indicator, surface drilling, totaled 47 million feet. In 1979, however, total drilling declined to 41 million feet, and during the first 8 months of 1980 the trend continued, as surface drilling was 27% less than for the same period in 1979. The total drilling for 1980 now is expected to be below 30 million feet, far less than the 39.4 million feet planned by industry at the beginning of the year. Falling uranium prices, the uncertainties of future uranium demand, rising costs, and the possibility of stiff foreign competition are the prime causes for the current reduction in domestic uranium exploration. Uranium exploration in the United States continues to be concentrated in the vicinity of major producing areas such as the San Juan Basin, Wyoming Basins, Texas Coastal Plain, Paradox Basin, and northeastern Washington, and in areas of recent discoveries including the Henry Mountains, Utah, the McDermitt caldera in Nevada and Oregon, and central Colorado. The distributions, by location, of total surface drilling for 1979 and the first half of 1980 are presented

  12. Exploring the nanoworld

    International Nuclear Information System (INIS)

    Cockayne, D.

    2002-01-01

    Full text: The nanoworld is a real world waiting to be explored and to be exploited, and the key to this world is microscopy. Modem techniques of microscopy reveal not only atoms and molecules, but also how they combine and interact. They allow us to explore not only the natural but also the synthesised nanoworld. Through this exploration, we can discover new natural forms which can act as templates for constructing novel materials of technological and scientific importance, we can obtain knowledge about the nanoworld (eg the structure of macromolecules) which gives us the means to manipulate the natural world, and we can discover how nature uses microstructure to achieve materials properties (eg strength) which we can then mimic. There are many modern forms of microscopy which are used in this exploration. They include not only a variety of microscopes (eg electron, atomic force, scanning tunnelling) but also an increasing range of sophisticated techniques such as electron tomography, image reconstruction, energy loss spectroscopy and high resolution microscopy, in which mathematical manipulation of the data is playing an increasingly important role. Meanwhile developments in aberration correctors and electron energy monochromation are taking microscopy into a new realm of resolution both in imaging and spectroscopy. Research at the nanoscale is causing a convergence between the biological and physical sciences, largely because the tools and techniques they use are becoming increasingly common to both fields. This challenges us to arrange our activities to optimise our efforts and resources. So we see significant developments in shared instrumentation and remote operation, and we see the setting up of nanotechnology institutes where researchers from across the biological, mathematical, materials and medical disciplines explore together. Copyright (2002) Australian Society for Electron Microscopy Inc

  13. Uranium exploration in Australia

    International Nuclear Information System (INIS)

    Battey, G.C.; Hawkins, B.W.

    1977-01-01

    As a result of exploration which recommenced in 1966 Australia's uranium reserves increased from 6,200 tonnes in 1967 to 227,000 tonnes uranium by June 1976. Most discoveries in the early 1950's were made by prospectors. The increase in reserves during the past decade is the result of exploration by companies utilising improved technology in areas selected as geologically favourable. These reserves were established at relatively low cost. In the Alligator Rivers Uranium Province the ''vein'' type deposits at Jabiluka, Ranger, Koongarra and Nabarlek contain 17% of the world's reserves. Most of these discoveries resulted from the investigation of airborne radiometric anomalies but cover over the prospective host rocks will necessitate the future use of costlier and more indirect exploration techniques. There was exploration for sandstone type uranium deposits in most of Australia's sedimentary basins. The greatest success was achieved in the Lake Frome Basin in South Australia. Other deposits were found in the Ngalia and Amadeus Basins in Central Australia and in the Westmoreland area, N.W. Queensland. A major uranium deposit was found in an unusual environment at Yeelirrie, Western Australia where carnotite occurs in a caliche and clay host which fills a shallow, ancient drainage channel. Although caliche occurrences are relatively widespread on the Precambrian shield no other economic deposit has been found. Recent discoveries in the Georgetown area of Queensland indicate the presence of another uranium province but it is too early to assess its potential. The ore occurs in clastic sediments at the base of a volcanic sequence overlying a Precambrian basement. Several companies which have established large uranium reserves have a number of additional attractive prospects. Exploration activity in Australia in 1975 was at a lower level than in previous years, but the potential for discovering further deposits is considered to be high

  14. Modulation of Colorectal Cancer Risk by Polymorphisms in 51Gln/His, 64Ile/Val, and 148Asp/Glu of APEX Gene; 23Gly/Ala of XPA Gene; and 689Ser/Arg of ERCC4 Gene

    Directory of Open Access Journals (Sweden)

    L. Dziki

    2017-01-01

    Full Text Available Polymorphisms in DNA repair genes may affect the activity of the BER (base excision repair and NER (nucleotide excision repair systems. Using DNA isolated from blood taken from patients (n=312 and a control group (n=320 with CRC, we have analyzed the polymorphisms of selected DNA repair genes and we have demonstrated that genotypes 51Gln/His and 148Asp/Glu of APEX gene and 23Gly/Ala of XPA gene may increase the risk of colorectal cancer. At the same time analyzing the gene-gene interactions, we suggest the thesis that the main factor to be considered when analyzing the impact of polymorphisms on the risk of malignant transformation should be intergenic interactions. Moreover, we are suggesting that some polymorphisms may have impact not only on the malignant transformation but also on the stage of the tumor.

  15. Exploring Urban Screens

    Directory of Open Access Journals (Sweden)

    Zlatan Krajina

    2009-12-01

    Full Text Available There is a tautological tendency in the widespread claims that urban space is 'me-diated'. Never before has the citizen, it is argued, been confronted with such an unprecedented array of signage. I depart from the rhetoric of 'biggest-ever-saturation' as not necessarily untrue, but as insufficient in exploring the diverse spatial operations of urban screens. I examine some contemporary cases of ani-mated architectural surfaces, informational panels, and advertising billboards, with reference to much longer standing cultural practices of spatial management in modern cities, such as illumination, to suggest that the contemporary display media do not mediate the city anew but re-invent urban space as a field of ubiqui-tous mediation. From that standpoint I suggest exploring urban screens as a both singular visual agents and indivisible items in plural structural assemblages, b complementary forces of public illumination, and c complex perceptual platforms in visual play of scale and distance.

  16. Exploring rationality in schizophrenia

    DEFF Research Database (Denmark)

    Revsbech, Rasmus; Mortensen, Erik Lykke; Owen, Gareth

    2015-01-01

    Background Empirical studies of rationality (syllogisms) in patients with schizophrenia have obtained different results. One study found that patients reason more logically if the syllogism is presented through an unusual content. Aims To explore syllogism-based rationality in schizophrenia. Meth...... differences became non-significant. Conclusions When taking intelligence and neuropsychological performance into account, patients with schizophrenia and controls perform similarly on syllogism tests of rationality.......Background Empirical studies of rationality (syllogisms) in patients with schizophrenia have obtained different results. One study found that patients reason more logically if the syllogism is presented through an unusual content. Aims To explore syllogism-based rationality in schizophrenia. Method...... Thirty-eight first-admitted patients with schizophrenia and 38 healthy controls solved 29 syllogisms that varied in presentation content (ordinary v. unusual) and validity (valid v. invalid). Statistical tests were made of unadjusted and adjusted group differences in models adjusting for intelligence...

  17. Exploring textual data

    CERN Document Server

    Lebart, Ludovic; Berry, Lisette

    1998-01-01

    Researchers in a number of disciplines deal with large text sets requiring both text management and text analysis. Faced with a large amount of textual data collected in marketing surveys, literary investigations, historical archives and documentary data bases, these researchers require assistance with organizing, describing and comparing texts. Exploring Textual Data demonstrates how exploratory multivariate statistical methods such as correspondence analysis and cluster analysis can be used to help investigate, assimilate and evaluate textual data. The main text does not contain any strictly mathematical demonstrations, making it accessible to a large audience. This book is very user-friendly with proofs abstracted in the appendices. Full definitions of concepts, implementations of procedures and rules for reading and interpreting results are fully explored. A succession of examples is intended to allow the reader to appreciate the variety of actual and potential applications and the complementary processin...

  18. Exploring improvisation in nursing.

    Science.gov (United States)

    Hanley, Mary Anne; Fenton, Mary V

    2007-06-01

    Improvisation has long been considered a function of music, dance, and the theatre arts. An exploration of the definitions and characteristics of this concept in relation to the art and practice of nursing provide an opportunity to illuminate related qualities within the field of nursing. Nursing has always demonstrated improvisation because it is often required to meet the needs of patients in a rapidly changing environment. However, little has been done to identify improvisation in the practice of nursing or to teach improvisation as a nursing knowledge-based skill. This article strives to explore the concept of improvisation in nursing, to describe the characteristics of improvisation as applied to nursing, and to utilize case studies to illustrate various manifestations of improvisation in nursing practice.

  19. The Primordial Inflation Explorer

    Science.gov (United States)

    Kogut, Alan J.

    2012-01-01

    The Primordial Inflation Explorer is an Explorer-class mission to measure the gravity-wave signature of primordial inflation through its distinctive imprint on the linear polarization of the cosmic microwave background. PIXIE uses an innovative optical design to achieve background-limited sensitivity in 400 spectral channels spanning 2.5 decades in frequency from 30 GHz to 6 THz (1 cm to 50 micron wavelength). The principal science goal is the detection and characterization of linear polarization from an inflationary epoch in the early universe, with tensor-to-scalar ratio r < 10(exp -3) at 5 standard deviations. The rich PIXIE data set will also constrain physical processes ranging from Big Bang cosmology to the nature of the first stars to physical conditions within the interstellar medium of the Galaxy. I describe the PIXIE instrument and mission architecture needed to detect the inflationary signature using only 4 semiconductor bolometers.

  20. Scientific Resource EXplorer

    Science.gov (United States)

    Xing, Z.; Wormuth, A.; Smith, A.; Arca, J.; Lu, Y.; Sayfi, E.

    2014-12-01

    Inquisitive minds in our society are never satisfied with curatedimages released by a typical public affairs office. They always want tolook deeper and play directly on original data. However, most scientificdata products are notoriously hard to use. They are immensely large,highly distributed and diverse in format. In this presentation,we will demonstrate Resource EXplorer (REX), a novel webtop applicationthat allows anyone to conveniently explore and visualize rich scientificdata repositories, using only a standard web browser. This tool leverageson the power of Webification Science (w10n-sci), a powerful enabling technologythat simplifies the use of scientific data on the web platform.W10n-sci is now being deployed at an increasing number of NASA data centers,some of which are the largest digital treasure troves in our nation.With REX, these wonderful scientific resources are open for teachers andstudents to learn and play.

  1. Optimal exploration target zones

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2008-09-01

    Full Text Available prospective map are the weights-of-evidence (WofE) method logistic regression canonical favorability analysis neural networks evidential belief functions Optimal Exploration Target Zones Debba, Carranza, Stein, van der Meer Introduction to Remote.... . . ): FITNESS FUNCTION φWMSD+V(Sn) = λ N(A) ∑ −→x ∈A P(−→x ) ∣ ∣ ∣ ∣−→x −QSn( −→x ) ∣ ∣ ∣ ∣ +(1− λ)s2(OSn) , (2) where QSn( −→x ) is the location vector of an optimal exploration focal point in Sn nearest to −→x , and s2(OSn) is the variance...

  2. An asteroseismology explorer

    International Nuclear Information System (INIS)

    Brown, T.M.; Cox, A.N.

    1987-01-01

    In response to a NASA opportunity, a proposal has been made to study the concept of an Asteroseismology Explorer (ASE). The goal of the ASE would be to measure solar-like oscillations on many (perhaps hundreds) of stars during a 1-year mission, including many members of open clusters. In this paper, the authors describe this proposal's observational goals, a strawman technical approach, and likely scientific rewards

  3. Gases in uranium exploration

    International Nuclear Information System (INIS)

    Wright, R.J.; Pacer, J.C.

    1981-01-01

    Interest continues to grow in the use of helium and radon detection as a uranium exploration tool because, in many instances, these radiogenic gases are the only indicators of deeply buried mineralization. The origin of these gases, their migration in the ground, the type of samples and measurement techniques are discussed. Case histories of comparative tests conducted on known uranium deposits at three geologically diverse sites in the United States of America are also presented. (author)

  4. Síndrome do ápice orbital associado com herpes zoster oftálmico em paciente HIV positivo: relato de caso Orbital apex syndrome and herpes zoster ophthalmicus in an HIV positive patient: case report

    Directory of Open Access Journals (Sweden)

    João Baptista Nigro Santiago Malta

    2004-12-01

    Full Text Available O presente relato tem como objetivo apresentar um caso raro de síndrome do ápice orbital associado com herpes zoster oftálmico de prognóstico reservado em paciente HIV positivo que procurou o pronto-socorro com quadro clínico de lesões crostosas em hemiface esquerda, dolorosa, acompanhado de baixa acuidade visual, diminuição da sensibilidade corneal e oftalmoplegia completa do olho esquerdo. A síndrome do ápice orbital é entidade rara que se caracteriza por ptose, proptose, oftalmoplegia interna e externa (acometimento do II, III, IV e VI nervos cranianos, prejuízo funcional da primeira divisão do nervo trigêmeo (nervo oftálmico e graus variados de diminuição da acuidade visual. O tratamento do herpes zoster oftálmico baseia-se no uso de antivirais sistêmicos, sendo que o prognóstico irá variar conforme o acometimento ocular.To present a rare case of orbital apex syndrome associated with herpes zoster ophthalmicus of unfavorable prognosis in an HIV positive patient, who arrived at the Emergency Room with the following clinical history: left facial crust lesions, low visual acuity, ocular pain, low corneal sensitivity and complete ophthalmoplegia of the left eye. The orbital apex syndrome is a rare disorder which is characterized by ptosis, proptosis, internal and external ophthalmoplegia (involvement of the second, third, fourth and sixth cranial nerves, damage to the first division of the trigeminal (ophthalmic nerve, and varied degrees of visual acuity loss. The treatment of herpes zoster ophthalmicus is based on the use of systemic antiviral drugs and the prognosis will depend on ocular damage.

  5. COACH – EXPLORER - MANAGER

    Directory of Open Access Journals (Sweden)

    Đorđe Nićin

    2006-06-01

    Full Text Available Nowdays technologies are characterised by the expert specialists. In training technologies there are also coaches-experts for some sports. Aport from governing training technology, thus he performs manager’s work (planning, programing, accomplishing, controlling, correcting the coach also performs the work of an explorer, because the work of the coach is creative, creating, exploring and it is necessary to include innovation into training process, and innovations are nothing but rehearse of someting new, what is but scientific approach to the training. More the coach succeeds in controlling more factors which influence the sport achievement, he will be more successful. To be able to do all that, the coach must observe, follow, control and correct sportist’s reactions on exercises and loads all the time. The coach demonstrates his activity even through marketing, educational psychological, administrative- technical, nutritional and entire useful social role, so his work is interdisciplinary very complex, important, public, and thus it is a subject to critics. In order to be successful, a modern coach must be an exellent expert-specialist, but also an explorer and manager, and before all a creator of training technology

  6. Exploring Monte Carlo methods

    CERN Document Server

    Dunn, William L

    2012-01-01

    Exploring Monte Carlo Methods is a basic text that describes the numerical methods that have come to be known as "Monte Carlo." The book treats the subject generically through the first eight chapters and, thus, should be of use to anyone who wants to learn to use Monte Carlo. The next two chapters focus on applications in nuclear engineering, which are illustrative of uses in other fields. Five appendices are included, which provide useful information on probability distributions, general-purpose Monte Carlo codes for radiation transport, and other matters. The famous "Buffon's needle proble

  7. Spacecraft exploration of asteroids

    International Nuclear Information System (INIS)

    Veverka, J.; Langevin, Y.; Farquhar, R.; Fulchignoni, M.

    1989-01-01

    After two decades of spacecraft exploration, we still await the first direct investigation of an asteroid. This paper describes how a growing international interest in the solar system's more primitive bodies should remedy this. Plans are under way in Europe for a dedicated asteroid mission (Vesta) which will include multiple flybys with in situ penetrator studies. Possible targets include 4 Vesta, 8 Flora and 46 Hestia; launch its scheduled for 1994 or 1996. In the United States, NASA plans include flybys of asteroids en route to outer solar system targets

  8. Exploring C++ 11

    CERN Document Server

    Lischner, Ray

    2014-01-01

    Exploring C++ divides C++ up into bite-sized chunks that will help you learn the language one step at a time. Assuming no familiarity with C++, or any other C-based language, you'll be taught everything you need to know in a logical progression of small lessons that you can work through as quickly or as slowly as you need.C++ can be a complicated language. Writing even the most straight-forward of programs requires you to understand many disparate aspects of the language and how they interact with one another. C++ doesn't lend itself to neat compartmentalization the way other languages do. Rat

  9. Exploration Medical System Demonstration

    Science.gov (United States)

    Rubin, D. A.; Watkins, S. D.

    2014-01-01

    BACKGROUND: Exploration class missions will present significant new challenges and hazards to the health of the astronauts. Regardless of the intended destination, beyond low Earth orbit a greater degree of crew autonomy will be required to diagnose medical conditions, develop treatment plans, and implement procedures due to limited communications with ground-based personnel. SCOPE: The Exploration Medical System Demonstration (EMSD) project will act as a test bed on the International Space Station (ISS) to demonstrate to crew and ground personnel that an end-to-end medical system can assist clinician and non-clinician crew members in optimizing medical care delivery and data management during an exploration mission. Challenges facing exploration mission medical care include limited resources, inability to evacuate to Earth during many mission phases, and potential rendering of medical care by non-clinicians. This system demonstrates the integration of medical devices and informatics tools for managing evidence and decision making and can be designed to assist crewmembers in nominal, non-emergent situations and in emergent situations when they may be suffering from performance decrements due to environmental, physiological or other factors. PROJECT OBJECTIVES: The objectives of the EMSD project are to: a. Reduce or eliminate the time required of an on-orbit crew and ground personnel to access, transfer, and manipulate medical data. b. Demonstrate that the on-orbit crew has the ability to access medical data/information via an intuitive and crew-friendly solution to aid in the treatment of a medical condition. c. Develop a common data management framework that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all activities pertaining to crew health and life sciences. d. Ensure crew access to medical data during periods of restricted ground communication. e. Develop a common data management framework that

  10. SpaceExplorer

    DEFF Research Database (Denmark)

    Hansen, Thomas Riisgaard

    2007-01-01

    Web pages are designed to be displayed on a single screen, but as more and more screens are being introduced in our surroundings a burning question becomes how to design, interact, and display web pages on multiple devices and displays. In this paper I present the SpaceExplorer prototype, which...... is able to display standard HTML web pages on multiple displays with only a minor modification to the language. Based on the prototype a number of different examples are presented and discussed and some preliminary findings are presented....

  11. The Cosmic Background Explorer

    Science.gov (United States)

    Gulkis, Samuel; Lubin, Philip M.; Meyer, Stephan S.; Silverberg, Robert F.

    1990-01-01

    The Cosmic Background Explorer (CBE), NASA's cosmological satellite which will observe a radiative relic of the big bang, is discussed. The major questions connected to the big bang theory which may be clarified using the CBE are reviewed. The satellite instruments and experiments are described, including the Differential Microwave Radiometer, which measures the difference between microwave radiation emitted from two points on the sky, the Far-Infrared Absolute Spectrophotometer, which compares the spectrum of radiation from the sky at wavelengths from 100 microns to one cm with that from an internal blackbody, and the Diffuse Infrared Background Experiment, which searches for the radiation from the earliest generation of stars.

  12. Uranium exploration techniques

    International Nuclear Information System (INIS)

    Nichols, C.E.

    1984-01-01

    The subject is discussed under the headings: introduction (genetic description of some uranium deposits; typical concentrations of uranium in the natural environment); sedimentary host rocks (sandstones; tabular deposits; roll-front deposits; black shales); metamorphic host rocks (exploration techniques); geologic techniques (alteration features in sandstones; favourable features in metamorphic rocks); geophysical techniques (radiometric surveys; surface vehicle methods; airborne methods; input surveys); geochemical techniques (hydrogeochemistry; petrogeochemistry; stream sediment geochemistry; pedogeochemistry; emanometry; biogeochemistry); geochemical model for roll-front deposits; geologic model for vein-like deposits. (U.K.)

  13. Exploring Opponent Formats

    DEFF Research Database (Denmark)

    Jensen, Mads Møller; Rasmussen, Majken; Grønbæk, Kaj

    2013-01-01

    of how the opponent format and relationships impact a game are almost absent in current research. Thus, this paper aims to elucidate how the perception of a competition differs, depending on the opponent format, by presenting a game mechanic framework. The paper furthermore presents an interactive...... football-training platform, as well as games designed to explore the different opponent formats. The games are qualitatively evaluated to illuminate the qualities of and distinctions between different types of opponent formats, proposed by the framework terminology....

  14. Uranium reserves and exploration activity

    International Nuclear Information System (INIS)

    Meehan, R.J.

    1975-01-01

    The strategy that ERDA plans to employ regarding resource appraisal is outlined. All types of uranium occurrences will be evaluated as sources of domestic ore reserves. Industry's exploration efforts will be compiled. These data will include information on land acquisition and costs, footage drilled and costs, estimates of exploration activities and expenditures, exploration for non-sandstone deposits, exploration in non-established areas, and foreign exploration plans and costs. Typical data in each of these areas are given

  15. Cosmochemistry and Human Exploration

    Science.gov (United States)

    Taylor, G. J.

    2004-12-01

    About 125 scientists, engineers, business men and women, and other specialists attended the sixth meeting of the Space Resources Roundtable, held at the Colorado School of Mines in Golden, Colorado. The meeting was co-sponsored by the Space Resources Roundtable, Inc. (a nonprofit organization dedicated to the use of space resources for the benefit of humankind), the Lunar and Planetary Institute, and the Colorado School of Mines. Presentations and discussions during the meeting made it clear that the knowledge gained from cosmochemical studies of the Moon and Mars is central to devising ways to use in situ resources. This makes cosmochemistry central to the human exploration and development of space, which cannot happen without extensive in situ resource utilization (ISRU). Cosmochemists at the meeting reported on an array of topics: the nature of lunar surface materials and our lack of knowledge about surface materials in permanently shadowed regions at the lunar poles; how to make reasonable simulated lunar materials for resource extraction testbeds, vehicle design tests, and construction experiments on Earth; and how to explore for resources on the Moon and Mars.

  16. Religion and Lunar Exploration

    Science.gov (United States)

    Pop, V.

    1969: The Eagle lands on the Moon. A moment that would not only mark the highest scientific achievement of all times, but would also have significant religious impli- cations. While the island of Bali lodges a protest at the United Nations against the US for desecrating a sacred place, Hopi Indians celebrate the fulfilment of an ancient prophecy that would reveal the "truth of the Sacred Ways". The plaque fastened to the Eagle - "We Came in Peace for All Mankind" would have contained the words "under God" as directed by the US president, if not for an assistant administrator at NASA that did not want to offend any religion. In the same time, Buzz Aldrin takes the Holy Communion on the Moon, and a Bible is left there by another Apollo mission - not long after the crew of Apollo 8 reads a passage from Genesis while circling the Moon. 1998: Navajo Indians lodge a protest with NASA for placing human ashes aboard the Lunar Prospector, as the Moon is a sacred place in their religion. Past, present and fu- ture exploration of the Moon has significant religious and spiritual implications that, while not widely known, are nonetheless important. Is lunar exploration a divine duty, or a sacrilege? This article will feature and thoroughly analyse the examples quoted above, as well as other facts, as for instance the plans of establishing lunar cemeteries - welcomed by some religions, and opposed by others.

  17. The advanced composition explorer

    International Nuclear Information System (INIS)

    Stone, E.C.; Burlaga, L.F.; Cummings, A.C.; Feldman, W.C.; Frain, W.E.; Geiss, J.; Gloeckler, G.; Gold, R.E.; Hovestadt, D.; Krimigis, S.M.; Mason, G.M.; McComas, D.; Mewaldt, R.A.; Simpson, J.A.; von Rosenvinge, T.T.; Wiedenbeck, M.E.

    1990-01-01

    The Advanced Composition Explorer (ACE) was recently selected as one of two new Explorer-class missions to be developed for launch during the mid-1990's ACE will observe particles of solar, interplanetary, interstellar, and galactic origins, spanning the energy range from that of the solar wind (∼1 keV/nucleon) to galactic cosmic ray energies (several hundred MeV/nucleon). Definitive studies will be made of the abundance of nearly all isotopes from H to Zn (1≤Z≤30), with exploratory isotope studies extending to Zr(Z=40). To accomplish this, the ACE payload includes six high-resolution spectrometers, each designed to provide the optimum charge, mass, or charge-state resolution in its particular energy range, and each having a geometry factor optimized for the expected flux levels, so as to provide a collecting power a factor of 10 to 1000 times greater than previous or planned experiments. The payload also includes several instruments of standard design that will monitor solar wind and magnetic field conditions and energetic H, He, and electron fluxes. We summarize here the scientific objectives, instrumentation, spacecraft, and mission approach that were defined for ACE during the Phase-A study period

  18. Human exploration mission studies

    Science.gov (United States)

    Cataldo, Robert L.

    1989-01-01

    The Office of Exploration has established a process whereby all NASA field centers and other NASA Headquarters offices participate in the formulation and analysis of a wide range of mission strategies. These strategies were manifested into specific scenarios or candidate case studies. The case studies provided a systematic approach into analyzing each mission element. First, each case study must address several major themes and rationale including: national pride and international prestige, advancement of scientific knowledge, a catalyst for technology, economic benefits, space enterprise, international cooperation, and education and excellence. Second, the set of candidate case studies are formulated to encompass the technology requirement limits in the life sciences, launch capabilities, space transfer, automation, and robotics in space operations, power, and propulsion. The first set of reference case studies identify three major strategies: human expeditions, science outposts, and evolutionary expansion. During the past year, four case studies were examined to explore these strategies. The expeditionary missions include the Human Expedition to Phobos and Human Expedition to Mars case studies. The Lunar Observatory and Lunar Outpost to Early Mars Evolution case studies examined the later two strategies. This set of case studies established the framework to perform detailed mission analysis and system engineering to define a host of concepts and requirements for various space systems and advanced technologies. The details of each mission are described and, specifically, the results affecting the advanced technologies required to accomplish each mission scenario are presented.

  19. Exploring Servitization in China

    DEFF Research Database (Denmark)

    Raja, Jawwad Z.; Frandsen, Thomas

    2017-01-01

    Purpose: Previous research has predominately focused on the servitization strategies of Western manufacturers in advanced economies, neglecting the potential for servitization in those which are emerging, such as China. This paper explores the role of the external service partner network of a Eur......Purpose: Previous research has predominately focused on the servitization strategies of Western manufacturers in advanced economies, neglecting the potential for servitization in those which are emerging, such as China. This paper explores the role of the external service partner network...... of a European manufacturer providing services in China, in order to develop a better understanding of the resulting and associated challenges. Design/methodology/approach: An in-depth case study approach was used to examine the parent company, its subsidiary in China and the related service partner network....... Data collection involved all three actors and took place in Denmark and China. Findings: The findings suggest that motivation, opportunity and ability (MOA) need not only be mutually reinforcing for the organization attempting to move towards services but also aligned between organizational units...

  20. Exploration Supply Chain Simulation

    Science.gov (United States)

    2008-01-01

    The Exploration Supply Chain Simulation project was chartered by the NASA Exploration Systems Mission Directorate to develop a software tool, with proper data, to quantitatively analyze supply chains for future program planning. This tool is a discrete-event simulation that uses the basic supply chain concepts of planning, sourcing, making, delivering, and returning. This supply chain perspective is combined with other discrete or continuous simulation factors. Discrete resource events (such as launch or delivery reviews) are represented as organizational functional units. Continuous resources (such as civil service or contractor program functions) are defined as enabling functional units. Concepts of fixed and variable costs are included in the model to allow the discrete events to interact with cost calculations. The definition file is intrinsic to the model, but a blank start can be initiated at any time. The current definition file is an Orion Ares I crew launch vehicle. Parameters stretch from Kennedy Space Center across and into other program entities (Michaud Assembly Facility, Aliant Techsystems, Stennis Space Center, Johnson Space Center, etc.) though these will only gain detail as the file continues to evolve. The Orion Ares I file definition in the tool continues to evolve, and analysis from this tool is expected in 2008. This is the first application of such business-driven modeling to a NASA/government-- aerospace contractor endeavor.

  1. Exploring Astrophysical Magnetohydrodynamics in the Laboratory

    Science.gov (United States)

    Manuel, Mario

    2014-10-01

    Plasma evolution in many astrophysical systems is dominated by magnetohydrodynamics. Specifically of interest to this talk are collimated outflows from accretion systems. Away from the central object, the Euler equations can represent the plasma dynamics well and may be scaled to a laboratory system. We have performed experiments to investigate the effects of a background magnetic field on an otherwise hydrodynamically collimated plasma. Laser-irradiated, cone targets produce hydrodynamically collimated plasma jets and a pulse-powered solenoid provides a constant background magnetic field. The application of this field is shown to completely disrupt the original flow and a new magnetically-collimated, hollow envelope is produced. Results from these experiments and potential implications for their astrophysical analogs will be discussed.

  2. Exploring exploration orientation and its determinants : Some empirical evidence

    NARCIS (Netherlands)

    Commandeur, H.R.; Volberda, H.W.; Sidhu, J.S.

    2004-01-01

    Adopting an information-process perspective, this article conceptualizes exploration orientation in terms of scope of information acquisition. In line with this conceptualization, a multidimensional operational measure of exploration orientation is developed and its internal consistency established.

  3. The design explorer project

    DEFF Research Database (Denmark)

    Pejtersen, Annelise Mark; Sonnenwald, Diane H.; Buur, Jacob

    1997-01-01

    the 'Design Explorer' research project whose goal is to specify requirements for an information system that will effectively help design team members from different domains and organizational cultures to locate and utilize diverse information sources and interact more effectively throughout the design process....... The project introduces a new approach to support of design; instead of design guidelines, support is given by creating a transparent information environment in which designers can navigate freely according to their individual preferences. The project is based on a framework that structures the dimensions......, or categories, of domain information which need to be available for a system or product designer/design team in order to determine the characteristics of the artefact, or object of design. These dimensions include information about the different work domains in which the product plays a role during its lifetime...

  4. Exploring the Sharing Economy

    DEFF Research Database (Denmark)

    Netter, Sarah

    Despite the growing interest on the part of proponents and opponents - ranging from business, civil society, media, to policy-makers alike - there is still limited knowledge about the working mechanisms of the sharing economy. The thesis is dedicated to explore this understudied phenomenon...... and to provide a more nuanced understanding of the micro- and macro-level tensions that characterize the sharing economy. This thesis consists of four research papers, each using different literature, methodology, and data sets. The first paper investigates how the sharing economy is diffused and is ‘talked......-level tensions experience by sharing platforms by looking at the case of mobile fashion reselling and swapping markets. The final paper combines the perspectives of different sharing economy stakeholders and outlines some of the micro and macro tensions arising in and influencing the organization of these multi...

  5. Nutrition for Space Exploration

    Science.gov (United States)

    Smith, Scott M.

    2005-01-01

    Nutrition has proven to be critical throughout the history of human exploration, on both land and water. The importance of nutrition during long-duration space exploration is no different. Maintaining optimal nutritional status is critical for all bodily systems, especially in light of the fact that that many are also affected by space flight itself. Major systems of concern are bone, muscle, the cardiovascular system, the immune system, protection against radiation damage, and others. The task ahead includes defining the nutritional requirements for space travelers, ensuring adequacy of the food system, and assessing crew nutritional status before, during, and after flight. Accomplishing these tasks will provide significant contributions to ensuring crew health on long-duration missions. In addition, development and testing of nutritional countermeasures to effects of space flight is required, and assessment of the impact of other countermeasures (such as exercise and pharmaceuticals) on nutrition is also critical for maintaining overall crew health. Vitamin D stores of crew members are routinely low after long-duration space flight. This occurs even when crew members take vitamin D supplements, suggesting that vitamin D metabolism may be altered during space flight. Vitamin D is essential for efficient absorption of calcium, and has numerous other benefits for other tissues with vitamin D receptors. Protein is a macronutrient that requires additional study to define the optimal intake for space travelers. Administration of protein to bed rest subjects can effectively mitigate muscle loss associated with disuse, but too much or too little protein can also have negative effects on bone. In another bed rest study, we found that the ratio of protein to potassium was correlated with the level of bone resorption: the higher the ratio, the more bone resorption. These relationships warrant further study to optimize the beneficial effect of protein on both bone and muscle

  6. Mineral nuclear exploration

    International Nuclear Information System (INIS)

    Filippov, E.M.

    1978-01-01

    The information on quantitative determination in rocks of water (humidity), rock-forming chemical elements, and various usefull components are presented. When considering separate chemical elements given are brief information on their content in natural objects, nuclear properties (the main reactions, their cross sections, isotope characteristics etc.). Possibilities of different nuclear methods in determination of chemical element concentrations in ores and rocks are analyzed. The greatest attention is paid to analysis of methods, based on gamma quantum and neutron irradiation. The results of application of laboratory nuclear-physical methods of rapid analysis are briefly considered, whereas the results of different field methods of nuclear exploration are considered in detail: field survey, well logging, inspection of mine roadway walls. In the appendix general information on chemical elements and sensitivity thresholds of certain activation methods are presented

  7. Exploring Entrepreneurial Network Relationships

    DEFF Research Database (Denmark)

    Norus, Jesper

    2003-01-01

    explores four different strategies for dealing with network relations; the research oriented strategy, the incubator strategy, the industrial partnering strategy, and the policy-oriented strategy. The research-oriented strategy is narrowly focusing on how a biotechnology firm transforms their scientific...... treated as a contingent factor. However only little attention have been giving to a specific focus on the strategies that new business ventures have obtained to establish the fit between small firms, university research, and public policies such as regulatory policies and R&D policies. The emergence...... results into promising technologies, services or products. The incubator strategy is concerned with localization and how to come about specific types of managerial problem in the initial stage of forming a business venture. The industrial partnering strategy concerns how to overcome the problem...

  8. Exploring bacterial lignin degradation.

    Science.gov (United States)

    Brown, Margaret E; Chang, Michelle C Y

    2014-04-01

    Plant biomass represents a renewable carbon feedstock that could potentially be used to replace a significant level of petroleum-derived chemicals. One major challenge in its utilization is that the majority of this carbon is trapped in the recalcitrant structural polymers of the plant cell wall. Deconstruction of lignin is a key step in the processing of biomass to useful monomers but remains challenging. Microbial systems can provide molecular information on lignin depolymerization as they have evolved to break lignin down using metalloenzyme-dependent radical pathways. Both fungi and bacteria have been observed to metabolize lignin; however, their differential reactivity with this substrate indicates that they may utilize different chemical strategies for its breakdown. This review will discuss recent advances in studying bacterial lignin degradation as an approach to exploring greater diversity in the environment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Exploring the Moon

    CERN Document Server

    Harland, David M

    2008-01-01

    David Harland opens with a review of the robotic probes, namely the Rangers which returned television before crashing into the Moon, the Surveyors which ''soft landed'' in order to investigate the nature of the surface, and the Lunar Orbiters which mapped prospective Apollo landing sites. He then outlines the historic landing by Apollo 11 in terms of what was discovered, and how over the next several missions the program was progressively geared up to enable the final three missions each to spend three days on comprehensive geological investigations. He concludes with a review of the robotic spacecraft that made remote-sensing observations of the Moon. Although aimed at the enthusiast, and can be read as an adventure in exploration, the book develops the scientific theme of lunar geology, and therefore will be of use as background reading for undergraduate students of planetary sciences. In addition, with the prospect of a resumption of human missions, it will help journalists understand what Apollo achieved ...

  10. Solar system exploration

    International Nuclear Information System (INIS)

    Briggs, G.A.; Quaide, W.L.

    1986-01-01

    Two fundamental goals lie at the heart of U.S. solar system exploration efforts: first, to characterize the evolution of the solar system; second, to understand the processes which produced life. Progress in planetary science is traced from Newton's definition of the principles of gravitation through a variety of NASA planetary probes in orbit, on other planets and traveling beyond the solar system. It is noted that most of the planetary data collected by space probes are always eventually applied to improving the understanding of the earth, moon, Venus and Mars, the planets of greatest interest to humans. Significant data gathered by the Mariner, Viking, Apollo, Pioneer, and Voyager spacecraft are summarized, along with the required mission support capabilities and mission profiles. Proposed and planned future missions to Jupiter, Saturn, Titan, the asteroids and for a comet rendzvous are described

  11. Exploring the brain

    International Nuclear Information System (INIS)

    Bloch, G.; Vernier, P.; Le Bihan, D.; Comtat, C.; Van Wassenhove, V.; Texier, I.; Planat-Chretien, A.; Poher, V.; Dinten, J.M.; Pannetier-lecoeur, M.; Trebossen, R.; Lethimonnier, F.; Eger, E.; Thirion, B.; Dehaene-Lambertz, G.; Piazza, M.; Mangin, J.F.; Dehaene, S.; Pallier, C.; Marti, S.; Klein, E.; Martinot, J.L.; Paillere, M.L.; Artiges, E.; Lemaitre, H.; Karila, L.; Houenou, J.; Sarrazin, S.; Hantraye, P.; Aron Badin, R.; Mergui, S.; Palfi, S.; Bemelmans, A.; Berger, F.; Frouin, V.; Pinel, J.F.; Crivello, F.; Mazoyer, B.; Flury-Herard, A.

    2014-01-01

    CEA (French Alternative Energies and Atomic Energy Commission) has been involved in brain research for over 50 years and this 62. issue of 'Clefs CEA' is the best occasion to come back on the latest advances in this wide field. The purpose is to show how neuroimaging combined with neuro sciences and computational sciences has shed light on various aspects of the brain life and experience such as for instance learning (with highlights on dyslexia and dyscalculia), vision, the feeling of time, consciousness, addictions, ageing, and neuro-degenerative diseases. This document is divided into 6 parts: 1) non-invasive exploration of the brain, 2) development, learning and plasticity of the brain, 3) cognitive architecture and the brain, 4) mental health and vulnerability, 5) neuro-degenerative diseases, and 6) identifying bio-markers for cerebral disorders. (A.C.)

  12. Exploring Seafloor Volcanoes in Cyberspace: NOAA's "Ocean Explorer" Inspires Inquiry

    Science.gov (United States)

    Hjelm, Elizabeth

    2011-01-01

    Seafloor exploration being done by scientists is an ideal way to introduce students to technology as a tool for inquiry. The same technology that allows scientists to share data in near real time can also provide students the tools to become researchers. NOAA's Ocean Explorer Explorations website is a rich research data bank that can be used by…

  13. Mineral exploration in developing countries

    International Nuclear Information System (INIS)

    Johnson, C.J.; Clark, A.L.

    1988-01-01

    The chapter provides an overview and comparisons of mineral exploration in Botswana and Papua New Guinea, including selection comparisons with Australia and Canada. It describes the history of exploration in Botswana and PNG. The concluding section summarizes the findings

  14. Language and Identity Explored

    Directory of Open Access Journals (Sweden)

    Thomas Rozanov

    2016-06-01

    Full Text Available The relationship between language and identity is widely discussed in applied linguistics, sociology, communications and other related scholarly fields. Furthermore, many researchers have focused on the post-Soviet region, which given its unique historical context allows for testing of this relationship. The widespread bilingualism as a result of historical russification and the linguistic transformations that occurred after the collapse of the Soviet Union make the region a ‘sociolinguistic playground’. Recent events in Ukraine have given grounds to further explore this relationship, now in attempt to link language and identity as potential forces for geopolitical change in the region. This paper presents an overview of existing research, theories, and opposing perspectives related to the relationship between language and identity, and considers complications such as historical russification, religious influence, socioeconomic factors, and education with regards to the Ukrainian and post-Soviet context.  I aim to illustrate the significance of language and its effects on socio-political change in the case of Ukraine, by presenting arguments and complications in support of the relationship between language and identity.

  15. Exploring the dusty Universe

    Directory of Open Access Journals (Sweden)

    Borghese, F

    2005-11-01

    Full Text Available Dust is an ubiquitous inhabitant of the interstellar medium, and leaves an unmistakable signature in its optical properties, and physico-chemical evolution. Although there is little direct knowledge of the true nature of interstellar dust grains, strong evidences point toward the possibility that such grains are composites of many small monomers (mainly made of silicates and carbonaceous materials. We consider two different models of fluffy dust aggregates, occurring as result of ballistic particle-cluster and cluster-cluster aggregation, and a cluster with a Gaussian-like sphere size distribution. We study the optical properties of such composite structures through the multipole fields and the Transition Matrix approach. Our results show the severe limits of applicability of the effective medium theories. By comparing radiation and gravitational forces, we also infer some relevant insights into the dynamical evolution of composite grains in the Solar System. We finally explore the possible role of composite fluffy dust grains in igniting an extraterrestrial prebiotic chemistry.

  16. Exploring digital professionalism.

    Science.gov (United States)

    Ellaway, Rachel H; Coral, Janet; Topps, David; Topps, Maureen

    2015-01-01

    The widespread use of digital media (both computing devices and the services they access) has blurred the boundaries between our personal and professional lives. Contemporary students are the last to remember a time before the widespread use of the Internet and they will be the first to practice in a largely e-health environment. This article explores concepts of digital professionalism and their place in contemporary medical education, and proposes a series of principles of digital professionalism to guide teaching, learning and practice in the healthcare professions. Despite the many risks and fears surrounding their use, digital media are not an intrinsic threat to medical professionalism. Professionals should maintain the capacity for deliberate, ethical, and accountable practice when using digital media. The authors describe a digital professionalism framework structured around concepts of proficiency, reputation, and responsibility. Digital professionalism can be integrated into medical education using strategies based on awareness, alignment, assessment, and accountability. These principles of digital professionalism provide a way for medical students and medical practitioners to embrace the positive aspects of digital media use while being mindful and deliberate in its use to avoid or minimize any negative consequences.

  17. MESSENGER: Exploring Mercury's Magnetosphere

    Science.gov (United States)

    Slavin, James A.

    2008-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. Mercury's magnetosphere is unique in many respects. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only - 1000 to 2000 km above the surface. For this reason there are no closed dri-fi paths for energetic particles and, hence, no radiation belts; the characteristic time scales for wave propagation and convective transport are short possibly coupling kinetic and fluid modes; magnetic reconnection at the dayside magnetopause may erode the subsolar magnetosphere allowing solar wind ions to directly impact the dayside regolith; inductive currents in Mercury's interior should act to modify the solar In addition, Mercury's magnetosphere is the only one with its defining magnetic flux tubes rooted in a planetary regolith as opposed to an atmosphere with a conductive ionosphere. This lack of an ionosphere is thought to be the underlying reason for the brevity of the very intense, but short lived, approx. 1-2 min, substorm-like energetic particle events observed by Mariner 10 in Mercury's magnetic tail. In this seminar, we review what we think we know about Mercury's magnetosphere and describe the MESSENGER science team's strategy for obtaining answers to the outstanding science questions surrounding the interaction of the solar wind with Mercury and its small, but dynamic magnetosphere.

  18. Antibacterial activities of coagulase-negative staphylococci from bovine teat apex skin and their inhibitory effect on mastitis-related pathogens.

    Science.gov (United States)

    Braem, G; Stijlemans, B; Van Haken, W; De Vliegher, S; De Vuyst, L; Leroy, F

    2014-05-01

    To explore antibacterial activities of coagulase-negative staphylococci (CoNS) from teat apices of dairy cows towards mastitis-causing pathogens. Of 254 CoNS, 38 displayed bacteriocin-like activity after a first screening. Seven of these strains displayed activity against at least one mastitis-related pathogen (Streptococcus uberis, Streptococcus dysgalactiae and Staphylococcus aureus). Staphylococcus chromogenes L217 displayed the strongest inhibitory effect, being active against all tested mastitis-related pathogens and most tested CoNS. Based on cation exchange and reversed-phase chromatography, in addition to N-terminal Edman degradation and PCR, the antibacterial peptide was identified as a nukacin-type bacteriocin and named nukacin L217. Although staphylococcal bacteriocins are generally found in the cell-free supernatants of liquid cultures, Staph. chromogenes L217 only led to detectable activity when grown on agar medium. Bacteriocin-like activities are not uncommon among CoNS from teat apices and may inhibit mastitis-causing pathogens, as found for nukacin L217 production by Staph. chromogenes L217. Nukacin L217 is the first identified bacteriocin of the species Staph. chromogenes and displays unusual production kinetics, that is, requiring surface growth of its producer. The fact that nukacins are produced by different CoNS species suggests a role in the teat skin ecosystem. © 2014 The Society for Applied Microbiology.

  19. Uranium exploration in Bangladesh

    International Nuclear Information System (INIS)

    Faruquee, A.R.

    1988-01-01

    The sedimentary succession of Bangladesh has continental sandstones with lignite and organic matter which are favourable host rocks for sedimentary uranium. The shield areas around Bangladesh are considered good source areas for uranium. Encouraged by this idea, the Bangladesh Atomic Energy Commission (BAEC) started an exploration programme in 1976 with the assistance of the IAEA and the United Nations Development Programme. Preliminary reconnaissance radiometric surveys carried out in 1976-1977 in the Chittagong, Chittagong hill tract and Sylhet districts identified some anomalies with 3 to 5 times the background (XBG). This was followed by regional reconnaissance radiometric surveys which were carried out between 1977 and 1985 in some of the anticlines of the Chittagong and Sylhet districts, including an airborne (helicopter) survey over the Jaldi area. These surveys resulted in the discovery of more than 300 radiometric anomalies of 3 to 60 XBG. They occur in the medium to fine grained ferruginous sandstones of the Dupitila and Tipam Formations of Mio-Pliocene age. These anomalous beds show variation in slime and heavy mineral contents. Some samples collected from the anomalous beds contain uranium and thorium ranging from 20 to 100 ppm and 100 to 1000 ppm, respectively. Exploratory drilling to a depth of about 400 ft was carried out on a very limited scale in the northeastern part of the Sylhet district. Gamma logging of these holes indicated many subsurface anomalies (3 to 21 XBG) in the Dupitila Formation. These anomalies are linked to thin layers with restricted lateral extensions. Geochemical orientation studies and radon surveys were done in some selected areas of Sylhet to test their suitability for further surveys. 9 refs, 13 figs, 4 tabs

  20. Effects of Nonconvective Electric Fields on Magnetospheric Plasma Dynamics.

    Science.gov (United States)

    1983-01-31

    I.S.E.E. data (June, 1981 issue J. Geophys. Res.) has made a large contribution toward describing the structure of the foreshock region just upstream from...narrow layer on the most sunward region of the foreshock [Bonifazi and Moreno, 1981a,b] and form the distribution which is classified as "reflected...the foreshock region toughes the quasi perpendicular bow shock [Eastman et. al., 1981]. Therefore, ions reflected at this point may run along the

  1. Geospace Plasma Dynamics Laboratory Annual Task Report (FY11)

    Science.gov (United States)

    2012-03-01

    Site Contractors: Nagendra Singh, Ph.D., Physicist , 0.5 MY Neil Grossbard, M.S., Mathematician , 0.7 MY Visitors: Publications: Articles in...PhD Project Manager Division Chief, RVB This report is published in the interest of scientific and technical...Annual Task Report (FY11) 5c. PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) 5d. PROJECT NUMBER 2311 Daniel Ober 5e. TASK NUMBER

  2. Classical plasma dynamics of Mie-oscillations in atomic clusters

    Science.gov (United States)

    Kull, H.-J.; El-Khawaldeh, A.

    2018-04-01

    Mie plasmons are of basic importance for the absorption of laser light by atomic clusters. In this work we first review the classical Rayleigh-theory of a dielectric sphere in an external electric field and Thomson’s plum-pudding model applied to atomic clusters. Both approaches allow for elementary discussions of Mie oscillations, however, they also indicate deficiencies in describing the damping mechanisms by electrons crossing the cluster surface. Nonlinear oscillator models have been widely studied to gain an understanding of damping and absorption by outer ionization of the cluster. In the present work, we attempt to address the issue of plasmon relaxation in atomic clusters in more detail based on classical particle simulations. In particular, we wish to study the role of thermal motion on plasmon relaxation, thereby extending nonlinear models of collective single-electron motion. Our simulations are particularly adopted to the regime of classical kinetics in weakly coupled plasmas and to cluster sizes extending the Debye-screening length. It will be illustrated how surface scattering leads to the relaxation of Mie oscillations in the presence of thermal motion and of electron spill-out at the cluster surface. This work is intended to give, from a classical perspective, further insight into recent work on plasmon relaxation in quantum plasmas [1].

  3. Plasma Dynamics of the Arc-Driven Rail Gun

    Science.gov (United States)

    1980-09-01

    Authors’ unpublished calculations. 11. A.B. Cambel , Plasma Physics and Magnetofluidmechanics (McGraw-Hill New York, 1963), Chap. 8. ’ 16 k T P = (1 +cO...Energy, and Forces (Wiley, New York, 1960), Chap. 9. 10. Authors’ unpublished calculations. 11. A.B. Cambel , Plasma Physics and Magnetofluidmechanics

  4. Anode plasma dynamics in the self-magnetic-pinch diode

    Directory of Open Access Journals (Sweden)

    Nichelle Bruner

    2011-02-01

    Full Text Available The self-magnetic-pinch diode is being developed as an intense electron beam source for pulsed-power-driven x-ray radiography. In high-power operation, the beam electrons desorb contaminants from the anode surface from which positive ions are drawn to the cathode. The counterstreaming electrons and ions establish an equilibrium current. It has long been recognized, however, that expanding electrode plasmas can disrupt this equilibrium and cause rapid reduction of the diode impedance and the radiation pulse. Recently developed numerical techniques, which enable simultaneous modeling of particle currents with 10^{13}  cm^{-3} densities to plasmas of near solid density, are applied to a model of the self-magnetic-pinch diode which includes the formation and evolution of anode surface plasmas. Two mechanisms are shown to cause rapid impedance loss, anode plasma expansion into the anode-cathode (A-K gap, and increased ion space-charge near the cathode surface. The former mechanism dominates for shorter A-K gaps, while the latter dominates for longer gaps. Model results qualitatively reproduce the time-dependent impedances measured for this diode.

  5. Geospace Plasma Dynamics: Final Report (2002-2007)

    National Research Council Canada - National Science Library

    Basu, Bamandas; Jasperse, John R

    2007-01-01

    .... Observations of transient sheets of field-aligned currents observed by DMSP during the main phase magnetic superstorm showed that under some highly stressed conditions contributions from low energy...

  6. Approximation scheme for strongly coupled plasmas: Dynamical theory

    International Nuclear Information System (INIS)

    Golden, K.I.; Kalman, G.

    1979-01-01

    The authors present a self-consistent approximation scheme for the calculation of the dynamical polarizability α (k, ω) at long wavelengths in strongly coupled one-component plasmas. Development of the scheme is carried out in two stages. The first stage follows the earlier Golden-Kalman-Silevitch (GKS) velocity-average approximation approach, but goes much further in its application of the nonlinear fluctuation-dissipation theorem to dynamical calculations. The result is the simple expression for α (k, ω), αatsub GKSat(k, ω) 4 moment sum rule. In the second stage, the above dynamical expression is made self-consistent at long wavelengths by postulating that a decomposition of the quadratic polarizabilities in terms of linear ones, which prevails in the k → 0 limit for weak coupling, can be relied upon as a paradigm for arbitrary coupling. The result is a relatively simple quadratic integral equation for α. Its evaluation in the weak-coupling limit and its comparison with known exact results in that limit reveal that almost all important correlational and long-time effects are reproduced by our theory with very good numerical accuracy over the entire frequency range; the only significant defect of the approximation seems to be the absence of the ''dominant'' γ ln γ -1 (γ is the plasma parameter) contribution to Im α

  7. Electron plasma dynamics during autoresonant excitation of the diocotron mode

    Energy Technology Data Exchange (ETDEWEB)

    Baker, C. J., E-mail: cbaker@physics.ucsd.edu; Danielson, J. R., E-mail: jrdanielson@ucsd.edu; Hurst, N. C., E-mail: nhurst@physics.ucsd.edu; Surko, C. M., E-mail: csurko@ucsd.edu [Physics Department, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States)

    2015-02-15

    Chirped-frequency autoresonant excitation of the diocotron mode is used to move electron plasmas confined in a Penning-Malmberg trap across the magnetic field for advanced plasma and antimatter applications. Plasmas of 10{sup 8} electrons, with radii small compared to that of the confining electrodes, can be moved from the magnetic axis to ≥90% of the electrode radius with near unit efficiency and reliable angular positioning. Translations of ≥70% of the wall radius are possible for a wider range of plasma parameters. Details of this process, including phase and displacement oscillations in the plasma response and plasma expansion, are discussed, as well as possible extensions of the technique.

  8. Neuropatía sensitiva trigeminal secundaria a granuloma de colesterol de la punta del peñasco del temporal Trigeminal neuralgia secondary to cholesterol granuloma of the petrous bone apex

    Directory of Open Access Journals (Sweden)

    M.A. Pons García

    2009-10-01

    Full Text Available La neuropatía aislada de la rama sensitiva del trigémino es una entidad poco habitual. Los pacientes suelen referir hipoestesia y /o disestesia generalmente a nivel de la segunda y tercera rama del trigémino, mientras que la neuralgia es muy infrecuente.¹ Su asociación con enfermedades sistémicas del tejido conectivo es bien conocida.² Se ha descrito asociada a distintas lesiones del SNC sobre todo tumores de fosa posterior o base de cráneo, así como neoplasias mandibulares.3,4 Presentamos una paciente con hipoestesia en el territorio V2-V3 asociada a dolor hemifacial paroxístico secundario a una lesión del peñasco del temporal.Trigeminal Neuralgia is an uncommon entity. The patients report hypoesthesia and/or dysesthesia of the second and third ramus of trigeminal nerve, while neuralgia is very rare.¹ Its association with systemic diseases of connective tissue is well know.² It has been described as being associated with different lesions of the central nervous system, especially with the posterior cavity or cranial base tumors, as well as jaw neoplasias.3,4 We presented a patient with hypoesthesia V2-V3 and hemi facial paroxysmal pain secondary to lesion of petrous apex of temporal bone.

  9. Marca Brasil: ficção ou realidade? uma análise das iniciativas da APEX- Brasil para a construção da marca Brasil

    Directory of Open Access Journals (Sweden)

    Daniela Motta R. Khauaja

    2008-01-01

    Full Text Available We live in a global economy and it is urgent for Brazil, through its governors and entrepreneurs, to increase its share in this economy. Branding the country can help create a strong identity for the country, which tends to collaborate with the exports of products made in this place. This study has the purpose of analyzing how brand Brasil was built and how it has been used by the Brazilian government to help its exports. In order to accomplish this objective, there was a review of the literature, concerning relevant concepts relative to global marketing, global branding and country as a brand. After this, the research method was explained and there was an analysis about the built of Brasil brand and the initiatives of the Brazilian government, more specifically of the Agência de Promoção de Exportações do Brasil (Apex-Brasil, for building Brazil as a brand. The initiative of creating brand Brasil, although quite late, was good, but, due to the lack of usage, the brand still seems to be more fiction than reality.

  10. Greater rate of cephalic screw mobilisation following proximal femoral nailing in hip fractures with a tip-apex distance (TAD) and a calcar referenced TAD greater than 25 mm.

    Science.gov (United States)

    Aicale, Rocco; Maffulli, Nicola

    2018-05-02

    To ascertain whether the tip-apex distance (TAD), calcar referenced TAD (CalTAD), and the sum of both (TADcalTAD) are predictive measurements of mobilisation of the cephalic screw in patients with trochanteric hip fractures. Between 2014 and 2015, 68 patients (mean age 86 years, 45 females, 23 males) with a trochanteric hip fracture underwent intramedullary nailing. The TAD and CalTAD were measured, and for each parameter, we calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). There is evidence of a statistically significant association between a TAD and CalTAD greater than 25 mm and a TADcalTAD greater than 50 mm and mobilisation of the cephalic screw. All measurements have similar sensitivity, but the TAD presents the highest specificity (p TAD and CalTAD less than 25 mm and a TADcalTAD less than 50 mm when using intramedullary fixation.

  11. Is acupuncture a useful adjunct to physiotherapy for older adults with knee pain?: The "Acupuncture, Physiotherapy and Exercise" (APEX study [ISRCTN88597683

    Directory of Open Access Journals (Sweden)

    Foster Nadine

    2004-09-01

    Full Text Available Abstract Background Acupuncture is a popular non-pharmacological modality for treating musculoskeletal pain. Physiotherapists are one of the largest groups of acupuncture providers within the NHS, and they commonly use it alongside advice and exercise. Conclusive evidence of acupuncture's clinical effectiveness and its superiority over sham interventions is lacking. The Arthritis Research Campaign (arc has funded this randomised sham-controlled trial which addresses three important questions. Firstly, we will determine the additional benefit of true acupuncture when used by physiotherapists alongside advice and exercise for older people presenting to primary care with knee pain. Secondly, we will evaluate sham acupuncture in the same way. Thirdly, we will investigate the treatment preferences and expectations of both the participants and physiotherapists participating in the study, and explore the effect of these on clinical outcome. We will thus investigate whether acupuncture is a useful adjunct to advice and exercise for treating knee pain and gain insight into whether this effect is due to specific needling properties. Methods/Design This randomised clinical trial will recruit 350 participants with knee pain to three intervention arms. It is based in 43 community physiotherapy departments in 21 NHS Trusts in the West Midlands and Cheshire regions in England. Patients aged 50 years and over with knee pain will be recruited. Outcome data will be collected by self-complete questionnaires before randomisation, and 6 weeks, 6 months and 12 months after randomisation and by telephone interview 2 weeks after treatment commences. The questionnaires collect demographic details as well as information on knee-related pain, movement and function, pain intensity and affect, main functional problem, illness perceptions, self-efficacy, treatment preference and expectations, general health and quality of life. Participants are randomised to receive a

  12. Comet radar explorer

    Science.gov (United States)

    Farnham, Tony; Asphaug, Erik; Barucci, Antonella; Belton, Mike; Bockelee-Morvan, Dominique; Brownlee, Donald; Capria, Maria Teresa; Carter, Lynn; Chesley, Steve; Farnham, Tony; Gaskell, Robert; Gim, Young; Heggy, Essam; Herique, Alain; Klaasen, Ken; Kofman, Wlodek; Kreslavsky, Misha; Lisse, Casey; Orosei, Roberto; Plaut, Jeff; Scheeres, Dan

    The Comet Radar Explorer (CORE) is designed to perform a comprehensive and detailed exploration of the interior, surface, and inner coma structures of a scientifically impor-tant Jupiter family comet. These structures will be used to investigate the origins of cometary nuclei, their physical and geological evolution, and the mechanisms driving their spectacular activity. CORE is a high heritage spacecraft, injected by solar electric propulsion into orbit around a comet. It is capable of coherent deep radar imaging at decameter wavelengths, high resolution stereo color imaging, and near-IR imaging spectroscopy. Its primary objective is to obtain a high-resolution map of the interior structure of a comet nucleus at a resolution of ¿100 elements across the diameter. This structure shall be related to the surface geology and morphology, and to the structural details of the coma proximal to the nucleus. This is an ideal complement to the science from recent comet missions, providing insight into how comets work. Knowing the structure of the interior of a comet-what's inside-and how cometary activity works, is required before we can understand the requirements for a cryogenic sample return mission. But more than that, CORE is fundamental to understanding the origin of comets and their evolution in time. The mission is made feasible at low cost by the use of now-standard MARSIS-SHARAD reflec-tion radar imaging hardware and data processing, together with proven flight heritage of solar electric propulsion. Radar flight heritage has been demonstrated by the MARSIS radar on Mars Express (Picardi et al., Science 2005; Plaut et al., Science 2007), the SHARAD radar onboard the Mars Reconnaissance Orbiter (Seu et al., JGR 2007), and the LRS radar onboard Kaguya (Ono et al, EPS 2007). These instruments have discovered detailed subsurface structure to depths of several kilometers in a variety of terrains on Mars and the Moon. A reflection radar deployed in orbit about a comet

  13. Exploring Disks Around Planets

    Science.gov (United States)

    Kohler, Susanna

    2017-07-01

    Giant planets are thought to form in circumstellar disks surrounding young stars, but material may also accrete into a smaller disk around the planet. Weve never detected one of these circumplanetary disks before but thanks to new simulations, we now have a better idea of what to look for.Image from previous work simulating a Jupiter-mass planet forming inside a circumstellar disk. The planet has its own circumplanetary disk of accreted material. [Frdric Masset]Elusive DisksIn the formation of giant planets, we think the final phase consists of accretion onto the planet from a disk that surrounds it. This circumplanetary disk is important to understand, since it both regulates the late gas accretion and forms the birthplace of future satellites of the planet.Weve yet to detect a circumplanetary disk thus far, because the resolution needed to spot one has been out of reach. Now, however, were entering an era where the disk and its kinematics may be observable with high-powered telescopes (like the Atacama Large Millimeter Array).To prepare for such observations, we need models that predict the basic characteristics of these disks like the mass, temperature, and kinematic properties. Now a researcher at the ETH Zrich Institute for Astronomy in Switzerland, Judit Szulgyi, has worked toward this goal.Simulating CoolingSzulgyi performs a series of 3D global radiative hydrodynamic simulations of 1, 3, 5, and 10 Jupiter-mass (MJ) giant planets and their surrounding circumplanetary disks, embedded within the larger circumstellar disk around the central star.Density (left column), temperature (center), and normalized angular momentum (right) for a 1 MJ planet over temperatures cooling from 10,000 K (top) to 1,000 K (bottom). At high temperatures, a spherical circumplanetary envelope surrounds the planet, but as the planet cools, the envelope transitions around 64,000 K to a flattened disk. [Szulgyi 2017]This work explores the effects of different planet temperatures and

  14. Uranium exploration techniques in Bolivia

    International Nuclear Information System (INIS)

    Virreira, V.

    1981-01-01

    The exploration techniques used by the Bolivian Nuclear Energy Commission/Comision Boliviana de Energia Nuclear (COBOEN) in certain areas of Bolivia that are considered promising from the standpoint of uranium deposits are presented in summary form. The methods and results obtained are described, including the techniques used by the Italian company AGIP-URANIUM during four years of exploration under contract with COBOEN. Statistical data are also given explaining the present level of uranium exploration in Bolivia. (author)

  15. Sustaining Exploration in Mature Basins

    International Nuclear Information System (INIS)

    Bayo, A.

    2002-01-01

    Exploration is a business like any other business driven by opportunity, resources and expectation of profit. Therefore, exploration will thrive anywhere the opportunities are significant, the resources are available and the outlook for profit (or value creation) is good. To sustain exploration activities anywhere, irrespective of the environment, there must be good understanding of the drivers of these key investment criteria. This paper will examine these investment criteria as they relate to exploration business and address the peculiarity of exploration in mature basin. Mature basins are unique environment that lends themselves a mix of fears, paradigms and realities, particularly with respect to the perception of value. To sustain exploration activities in a mature basin, we need to understand these perceptions relative to the true drivers of profitability. Exploration in the mature basins can be as profitable as exploration in emerging basins if the dynamics of value definition-strategic and fiscal values are understood by operators, regulators and co ventures alike. Some suggestions are made in this presentation on what needs to be done in addressing these dynamic investment parameters and sustaining exploration activities in mature basins

  16. Overseas uranium exploration by PNC

    International Nuclear Information System (INIS)

    Nagashima, Reiji; Iida, Yoshimasa; Shigeta, Naotaka; Takahashi, Osamu; Yamagishi, Akiko; Miyada, Hatsuho; Kobayashi, Takao

    1998-01-01

    Japan entirely depends on overseas countries for uranium resources for its nuclear electric power generation due to the lack of domestic resources. In order to secure a steady supply of natural uranium, Japanese government has implemented a long-term procurement policy through purchase contracts by private sectors, subsidizing private sectors' exploration and initial stage exploration outside the reach of private sectors' activity by PNC (Power Reactor and Nuclear Fuel Development Corporation). The subsequent long slump in the price of uranium, however, led most of Japanese private sectors to discontinue their exploration activity. Upon this situation, PNC has pursued a little more advanced stage exploration in addition to basic research and initial stage exploration and has improved its exploration techniques to enable the discovery of deep-seated uranium ore deposits. As the result, PNC has acquired significant uranium exploration tenements and interests similar to those owned by major uranium companies such as Cameco and Cogema. PNC has also contributed to discovery of new uranium deposits. In this report, the history of PNC's activities and its role in the long-term uranium procurement policy are reviewed and it is also described about the outcome thorough its activities and future exploration trend and the tasks. (author)

  17. Dog Mathematics: Exploring Base-4

    Science.gov (United States)

    Kurz, Terri L.; Yanik, H. Bahadir; Lee, Mi Yeon

    2016-01-01

    Using a dog's paw as a basis for numerical representation, sixth grade students explored how to count and regroup using the dog's four digital pads. Teachers can connect these base-4 explorations to the conceptual meaning of place value and regrouping using base-10.

  18. Colombia extends its exploration horizon

    International Nuclear Information System (INIS)

    Carta Petrolera

    1997-01-01

    The Return 1 Contract, currently being awarded under the tender system, faithfully reflects Colombia's new approach to hydrocarbon exploration and exploitation. This policy aims to increase reserves and has Ecopetrol assume a more aggressive role in its direct activities by sharing the exploration risks with private partners

  19. MARCA BRASIL - FICÇÃO OU REALIDADE?: uma análise das iniciativas da APEX-Brasil para a construção da marca Brasil

    Directory of Open Access Journals (Sweden)

    DANIELA MOTTA R. KHAUAJA

    2007-01-01

    Full Text Available Vivemos em uma economia global e é urgente que o Brasil, por meio de seus governantes e empresariado, busque a inserção nessa economia de forma mais efetiva. A marca-país pode ajudar na criação de uma forte identidade para o país, o que tende a colaborar com a venda de produtos oriundos desse país. O presente estudo se propõe a analisar como a marca Brasil foi construída e como ela tem sido explorada pelo governo brasileiro para ajudar na inserção de produtos nacionais no comércio internacional. Para tal, foi feita uma revisão da literatura, abordando conceitos relevantes e relativos ao marketing global, a produtos e marcas globais e à marca-país. Em seguida, explicitou-se o método do estudo e fez-se a análise da construção da marca Brasil e das iniciativas do governo brasileiro, mais especificamente da Agência de Promoção de Exportações do Brasil (Apex-Brasil, à construção da marca Brasil. A iniciativa da criação da marca Brasil, embora tardia, parece muito louvável, mas, por sua tímida utilização, a marca Brasil ainda parece mais ficção do que realidade.

  20. New Age for Lunar Exploration

    Science.gov (United States)

    Taylor, G. J.; Martel, L. M. V.

    2018-04-01

    Lunar-focused research and plans to return to the lunar surface for science and exploration have reemerged since the Space Policy Directive-1 of December 11, 2017 amended the National Space Policy to include the following, "Lead an innovative and sustainable program of exploration with commercial and international partners to enable human expansion across the solar system and to bring back to Earth new knowledge and opportunities. Beginning with missions beyond low-Earth orbit, the United States will lead the return of humans to the Moon for long-term exploration and utilization, followed by human missions to Mars and other destinations." In response to this revision, NASA proposes a Lunar Exploration and Discovery Program in the U.S. fiscal year 2019 Budget Request. It supports NASA's interests in commercial and international partnerships in Low-Earth Orbit (LEO), long-term exploration in Cislunar space beyond LEO, and research and exploration conducted on the Moon to inform future crewed missions, even to destinations beyond the Moon. (Cislunar refers to the volume of space between LEO and the Moon's orbital distance.) The lunar campaign strengthens the integration of human and robotic activities on the lunar surface with NASA's science, technology, and exploration goals.

  1. Trends in exploration and exploration equipment for uranium

    International Nuclear Information System (INIS)

    Raitz, C.H.

    1976-01-01

    Uranium exploration once again is in a ''boom'' cycle. The energy needs of the OPEC and non-OPEC countries alike have created a demand for uranium which appears certain to increase in future years. In turn, this demand has stimulated a dramatic rise in both the price of uranium and the exploration activity necessary to discover new reserves. One immediate reaction to the sudden increase in uranium exploration activity has been the evaluation of old exploration methods and equipment. This paper briefly reviews some of the traditional equipment and techniques which currently are being refined and updated. Undoubtedly this equipment, complemented with good exploration planning and judgment, will continue to be relied upon for many years and will lead to the discovery of many new deposits. The paper also covers in greater detail some of the newer, less conventional techniques and equipment now being introduced for uranium exploration. These new methods may be expected to keep this country in the forefront among the uranium producers of the world

  2. Efecto de la localización del electrodo ventricular derecho (tracto de salida vs. ápex sobre la sincronía ventricular mecánica, en pacientes sometidos a terapia de implante de marcapaso cardiaco Effect of right ventricular electrode location (outflow tract vs. apex on mechanical ventricular synchrony in patients that underwent pacemaker implant therapy

    Directory of Open Access Journals (Sweden)

    Oscar S Rincón

    2008-12-01

    Full Text Available Objetivo: evaluar a profundidad el efecto de la estimulación ventricular desde el tracto de salida del ventrículo derecho y el ápex, sobre la sincronía ventricular mecánica. Materiales y métodos: estudio analítico de cohorte, en el que se realizó ecocardiograma transtorácico pre y post implante de marcapaso a 20 pacientes (diez por cada grupo con indicación de marcapaso definitivo, con implante del electrodo en el tracto de salida del ventrículo derecho y el ápex, sin cardiopatía estructural, fracción de eyección > 50%; QRS y conducción aurículo-ventricular normal, con el fin de evaluar la asincronía ventricular mecánica (modo M y Doppler tisular y los parámetros de implante y programación del dispositivo. Análisis estadístico: los resultados se presentan como promedios, desviación estándar o porcentajes. Las variables continuas se compararon utilizando prueba Chi cuadrado y ANOVA. Se consideró como estadísticamente significativa una p Objective: to assess in depth the effect of ventricular stimulation from the right ventricular outflow tract and the apex on mechanical ventricular synchrony. Materials and Methods: cohort analytical study. 20 patients with indication of definitive pacemaker indication underwent transthoracic echocardiogram before and after pacemaker implant with electrode implantation in the right ventricular outflow tract and in the apex (10 patients in each group. There was no structural cardiopathy, ejection fraction was > 50%, QRS and AV conduction were normal. Mechanical ventricular asynchrony (M mode and tissue doppler and implant and device parameters were evaluated. Statistical Analysis: results are given as mean values, standard deviation or percentages. Continuous variables were compared using Chi-square test and ANOVA. A p <0.05 value was considered statistically significant. Results: in five patients (25% a pre-implant ventricular asynchrony was found; in seven (70% ventricular asynchrony

  3. Powering the Space Exploration Initiative

    International Nuclear Information System (INIS)

    Bennett, G.L.

    1991-01-01

    The Space Exploration Initiative (SEI) establishes the long-term goal of returning to the Moon and then exploring Mars. One of the prerequisites of SEI is the Exploration Technology Program which includes program elements on space nuclear power and surface solar power. These program elements in turn build upon the ongoing NASA research and technology base program in space energy conversion. There is a wide range of missions in NASA's strategic planning and most would benefit from power sources with improved efficiency, lighter weight and reduced cost

  4. Yields of historical exploration programs

    International Nuclear Information System (INIS)

    Huslende, T.

    1995-01-01

    The paper relates to an method of evaluation developed for analysing the yield of historical exploration programs by computerized simulation. The most important elements show in coarse features how the results can be used in the different analyses. The evaluation is to be executed annually for the comparison and sorting of data from different offshore sites. Topics are exploration evaluation study, evaluation process, handling of exploration costs, discovered reserves, development projects, cash flow analysis, analysis of results, finding cost, international comparison. 1 ref., 11 figs

  5. Borehole logging for uranium exploration

    International Nuclear Information System (INIS)

    1982-01-01

    The present text has been prepared taking into account the requirements of both developing countries, which might be at an incipient stage of uranium exploration, and industrialized countries, where more advanced exploration and resource evaluation techniques are commonly in use. While it was felt necessary to include some discussion of exploration concepts and fundamental physical principles underlying various logging methods, it was not the intention of the consultants to provide a thorough, detailed explanation of the various techniques, or even to give a comprehensive listing thereof. However, a list of references has been included, and it is strongly recommended that the serious student of mineral logging consult this list for further guidance

  6. Ethnomathematics: Exploration in Javanese culture

    Science.gov (United States)

    Risdiyanti, Irma; Charitas Indra Prahmana, Rully

    2017-12-01

    This research is the exploration study to indicate the correlation between mathematics and Javanese culture. These studies have a purpose of exploring Javanese culture in Yogyakarta that contains mathematics concept namely Batik. The activity of society in making Batik in all regency at Yogyakarta is the focus of this study. The research use ethnography method. The technic to collection data uses principles in ethnography such as observation, interview, documentation, and field note making with the original ethnography description. The result is exploration ethnomathematics in the several motifs of Yogyakarta batik that contains philosophy, deep cultural value, and mathematics concept, especially geometry transform subject.

  7. The business of petroleum exploration

    International Nuclear Information System (INIS)

    Steinmetz, R.

    1992-01-01

    This book contains the proceedings of the Business of Petroleum Exploration. The following topics are included: Petroleum business; Economic aspects of the business; Managing business; and Legal, Political, Ethical and environment aspects of the business

  8. Starting to Explore Wind Power

    Science.gov (United States)

    Hare, Jonathan

    2008-01-01

    Described is a simple, cheap and versatile homemade windmill and electrical generator suitable for a school class to use to explore many aspects and practicalities of using wind to generate electrical power. (Contains 8 figures.)

  9. China's roadmap for planetary exploration

    Science.gov (United States)

    Wei, Yong; Yao, Zhonghua; Wan, Weixing

    2018-05-01

    China has approved or planned a string of several space exploration missions to be launched over the next decade. A new generation of planetary scientists in China is playing an important role in determining the scientific goals of future missions.

  10. Isotope analysis in petroleum exploration

    International Nuclear Information System (INIS)

    Rodrigues, R.

    1982-01-01

    The study about isotopic analysis in petroleum exploration performed at Petrobras Research Center is showed. The results of the petroleum recuperation in same Brazilian basin and shelves are comented. (L.H.L.L.) [pt

  11. Recent developments in uranium exploration

    International Nuclear Information System (INIS)

    Barretto, P.M.

    1981-01-01

    Even in the most experienced and competent hands, mineral exploration is an expensive, risky, and time-consuming business. Uranium exploration is no different from the above, its sole advantage being that the uranium can be detected from afar because it emits gamma radiation. Therefore, radiometric techniques are the most useful exploration methods. In developing countries that are interested in starting or that have started uranium exploration programmes there are other problems as well as those outlined above: Lack of, or difficulty in obtaining, the requisite number of qualified personnel for field and laboratory activities (lack of manpower); Lack of administrative and technological infrastructure needed to support an exploration effort (lack of technology); and Relatively small budget for a multi-year programme (lack of money). In view of the above it is very important that the time and resources available to an exploration programme are utilized wisely. This means selecting optimum methods of obtaining the information needed and avoiding unnecessary duplication of effort by government organizations. Such duplication of effort in exploration is common in developing countries. In some cases three government organizations have been discovered doing geological mapping of the same area. As the amount, quality and availability of geological information vary from place to place, and since the exploration programmes can have different sizes and objectives, following a standard procedure is difficult. The procedures or sequences outlined are suggested for areas that are being prospected for the first time. If carried out systematically, it will be possible to obtain both an inventory of the geology, and an assessment of the mineral potential of a given area with minimum investment and maximum efficiency

  12. INTEGRATED EXPLORATION OF GEOTHERMAL RESOURCES

    OpenAIRE

    A. B. Alkhasov; D. A. Аlkhasova; R. M. Aliyev; A. Sh. Ramazanov

    2016-01-01

    The aim. The aim is to develop the energy efficient technologies to explore hydro geothermal resources of different energy potential.Methods. Evaluation of the effectiveness of the proposed technologies has been carried out with the use of physical and mathematical, thermodynamic and optimization methods of calculation and the physical and chemical experimental research.Results. We propose the technology of integrated exploration of low-grade geothermal resources with the application of heat ...

  13. Uranium exploration/development policy

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The Honeymoon joint venturers have been advised that their request for compensation has been refused. This follows the South Australian Government's decision not to grant a mining lease. An application for a retention lease to the joint venturers at Beverley was also refused. The Government has formulated clear guidelines for both retention leases and exploration licences which will be applied to all companies engaged specifically in exploration for uranium

  14. New NASA Technologies for Space Exploration

    Science.gov (United States)

    Calle, Carlos I.

    2015-01-01

    NASA is developing new technologies to enable planetary exploration. NASA's Space Launch System is an advance vehicle for exploration beyond LEO. Robotic explorers like the Mars Science Laboratory are exploring Mars, making discoveries that will make possible the future human exploration of the planet. In this presentation, we report on technologies being developed at NASA KSC for planetary exploration.

  15. APEX CREATURES: A MIRROR OF ECOLOGICAL BALANCE

    Directory of Open Access Journals (Sweden)

    Avin

    2016-05-01

    Full Text Available INTRODUCTION South-Western coast of India, we find places where the tribal people and their cultures are still thriving in this part of the world and also has managed to survive the impact of today’s ever growing effects of globalisation.

  16. APEX CREATURES: A MIRROR OF ECOLOGICAL BALANCE

    OpenAIRE

    Avin; Suresh; Shishir

    2016-01-01

    INTRODUCTION South-Western coast of India, we find places where the tribal people and their cultures are still thriving in this part of the world and also has managed to survive the impact of today’s ever growing effects of globalisation.

  17. Exploration Medical Capability - Technology Watch

    Science.gov (United States)

    Krihak, Michael; Watkins, Sharmila; Barr, Yael; Barsten, Kristina; Fung, Paul; Baumann, David

    2011-01-01

    The objectives of the Technology Watch process are to identify emerging, high-impact technologies that augment current ExMC development efforts, and to work with academia, industry, and other government agencies to accelerate the development of medical care and research capabilities for the mitigation of potential health issues that could occur during space exploration missions. The establishment of collaborations with these entities is beneficial to technology development, assessment and/or insertion. Such collaborations also further NASA s goal to provide a safe and healthy environment for human exploration. The Tech Watch project addresses requirements and capabilities identified by knowledge and technology gaps that are derived from a discrete set of medical conditions that are most likely to occur on exploration missions. These gaps are addressed through technology readiness level assessments, market surveys, collaborations and distributed innovation opportunities. Ultimately, these gaps need to be closed with respect to exploration missions, and may be achieved through technology development projects. Information management is a key aspect to this process where Tech Watch related meetings, research articles, collaborations and partnerships are tracked by the HRP s Exploration Medical Capabilities (ExMC) Element. In 2011, ExMC will be introducing the Tech Watch external website and evidence wiki that will provide access to ExMC technology and knowledge gaps, technology needs and requirements documents.

  18. Lunar Exploration Missions Since 2006

    Science.gov (United States)

    Lawrence, S. J. (Editor); Gaddis, L. R.; Joy, K. H.; Petro, N. E.

    2017-01-01

    The announcement of the Vision for Space Exploration in 2004 sparked a resurgence in lunar missions worldwide. Since the publication of the first "New Views of the Moon" volume, as of 2017 there have been 11 science-focused missions to the Moon. Each of these missions explored different aspects of the Moon's geology, environment, and resource potential. The results from this flotilla of missions have revolutionized lunar science, and resulted in a profoundly new emerging understanding of the Moon. The New Views of the Moon II initiative itself, which is designed to engage the large and vibrant lunar science community to integrate the results of these missions into new consensus viewpoints, is a direct outcome of this impressive array of missions. The "Lunar Exploration Missions Since 2006" chapter will "set the stage" for the rest of the volume, introducing the planetary community at large to the diverse array of missions that have explored the Moon in the last decade. Content: This chapter will encompass the following missions: Kaguya; ARTEMIS (Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon’s Interaction with the Sun); Chang’e-1; Chandrayaan-1; Moon Impact Probe; Lunar Reconnaissance Orbiter (LRO); Lunar Crater Observation Sensing Satellite (LCROSS); Chang’e-2; Gravity Recovery and Interior Laboratory (GRAIL); Lunar Atmosphere and Dust Environment Explorer (LADEE); Chang’e-3.

  19. NOAA Office of Exploration and Research > Exploration > Systematic

    Science.gov (United States)

    Vessel (E/V) Nautilus in real-time on Internet 2 and the Internet. A legacy of high quality imagery, high . Contact Information for OER Okeanos Explorer Program: Craig Russell NOAA/OAR/OER 7600 Sand Point Way NE | Disclaimer | Privacy Policy | FOIA | Web Accessibility Statement | Information Quality Copyright NOAA 2013

  20. Historic Cosmology Identity and Exploration

    Science.gov (United States)

    Nebergall, K.

    The role of the soul and spirit in the composition of human endeavour generally takes the form of motivational poster catch phrases or third-hand quotes. If the spirit equals the life of a creature, and one of the signs of life is locomotion, are humans not obliged by something even deeper than our humanity to explore the universe? This paper examines the roots and perspectives of our worldviews on identity, exploration, and the limitations and capacities of humanity. It will equip the reader to discuss the nature of exploration with audiences across a wide range of worldviews. Current cultures, regardless of religion or politics, are looped into a series of nihilistic patterns that must be broken by rediscovering our nature as living beings, and our obligations as human beings.

  1. Artistic explorations of the brain

    Directory of Open Access Journals (Sweden)

    Eberhard E Fetz

    2012-02-01

    Full Text Available The symbiotic relationships between art and the brain begin with the obvious fact that brain mechanisms underlie the creation and appreciation of art. Conversely, many spectacular images of neural structures have remarkable aesthetic appeal. But beyond its fascinating forms, the many functions performed by brain mechanisms provide a profound subject for aesthetic exploration. Complex interactions in the tangled neural networks in our brain miraculously generate coherent behavior and cognition. Neuroscientists tackle these phenomena with specialized methodologies that limit the scope of exposition and are comprehensible to an initiated minority. Artists can perform an end run around this impasse by representing the brain’s many functions in a manner that can communicate to a wide and receptive audience. This paper explores the ways that brain mechanisms can provide a largely untapped subject for artistic exploration.

  2. Exploration through Business Model Innovation

    DEFF Research Database (Denmark)

    Knab, Sebastian; Rohrbeck, René

    2015-01-01

    With this research we aim to enhance our understanding about how incumbents can explore emerging opportunities through business model innovation. Using a multiple-case, longitudinal research design spanning 2008 to 2014 we investigate exploration activities of the four largest German energy...... utilities in the emerging virtual power plant market. Based on the behavioral theory of the firm, we study how the cognitive and physical elements of an incumbent’s strategy can be changed and how these changes affect its business model innovation activities in the exploration process. Our preliminary...... findings suggest that the use of synergies and probing can lead to changing physical elements and primarily increase business model maturity. CEO change and structural separation can lead to changing cognitive elements and primarily increase business model sophistication....

  3. Artistic explorations of the brain

    Science.gov (United States)

    Fetz, Eberhard E.

    2012-01-01

    The symbiotic relationships between art and the brain begin with the obvious fact that brain mechanisms underlie the creation and appreciation of art. Conversely, many spectacular images of neural structures have remarkable aesthetic appeal. But beyond its fascinating forms, the many functions performed by brain mechanisms provide a profound subject for aesthetic exploration. Complex interactions in the tangled neural networks in our brain miraculously generate coherent behavior and cognition. Neuroscientists tackle these phenomena with specialized methodologies that limit the scope of exposition and are comprehensible to an initiated minority. Artists can perform an end run around these limitations by representing the brain's remarkable functions in a manner that can communicate to a wide and receptive audience. This paper explores the ways that brain mechanisms can provide a largely untapped subject for artistic exploration. PMID:22347178

  4. Exploration Laboratory Analysis FY13

    Science.gov (United States)

    Krihak, Michael; Perusek, Gail P.; Fung, Paul P.; Shaw, Tianna, L.

    2013-01-01

    The Exploration Laboratory Analysis (ELA) project supports the Exploration Medical Capability (ExMC) risk, which is stated as the Risk of Inability to Adequately Treat an Ill or Injured Crew Member, and ExMC Gap 4.05: Lack of minimally invasive in-flight laboratory capabilities with limited consumables required for diagnosing identified Exploration Medical Conditions. To mitigate this risk, the availability of inflight laboratory analysis instrumentation has been identified as an essential capability in future exploration missions. Mission architecture poses constraints on equipment and procedures that will be available to treat evidence-based medical conditions according to the Space Medicine Exploration Medical Conditions List (SMEMCL), and to perform human research studies on the International Space Station (ISS) that are supported by the Human Health and Countermeasures (HHC) element. Since there are significant similarities in the research and medical operational requirements, ELA hardware development has emerged as a joint effort between ExMC and HHC. In 2012, four significant accomplishments were achieved towards the development of exploration laboratory analysis for medical diagnostics. These achievements included (i) the development of high priority analytes for research and medical operations, (ii) the development of Level 1 functional requirements and concept of operations documentation, (iii) the selection and head-to-head competition of in-flight laboratory analysis instrumentation, and (iv) the phase one completion of the Small Business Innovation Research (SBIR) projects under the topic Smart Phone Driven Blood-Based Diagnostics. To utilize resources efficiently, the associated documentation and advanced technologies were integrated into a single ELA plan that encompasses ExMC and HHC development efforts. The requirements and high priority analytes was used in the selection of the four in-flight laboratory analysis performers. Based upon the

  5. Uranium exploration planning and strategy

    International Nuclear Information System (INIS)

    Smith, A.Y.; Tauchid, M.

    1991-01-01

    A country may decide to begin uranium exploration for any of the following three reasons: 1. To meet the needs of a domestic nuclear power programme; 2. To supply uranium as a commodity to the world market in order to earn foreign exchange; 3. To acquire national information on the country's mineral resource planning. In any of these cases, a country must make some basic decisions regarding the means and modes whereby the uranium exploration will be carried out - by national organizations exclusively; by state organizations in joint venture with outside interests by foreign interests under the control of national regulations. Most uranium exploration is carried out following an exploration strategy in which the programme is divided into a series of steps or stages. Each of the phases is designed to eliminate areas of low potential to contain uranium deposits, while focusing attention on areas of higher potential that will be explored in greater detail at higher cost in the subsequent phase. The methods used in each phase are selected to provide the maximum information at the minimum cost so that at the end of each phase a decision can be made whether to continue to the next phase of stop. Because uranium exploration is a high cost high risk activity, governments must make decisions at the outset whether they wish to carry our the work alone and whether they can support the costs involved, or whether they wish to attract foreign investors to help absorb the costs and therefore the risks. In either case, major policy decisions are required to be made to establish the legal and fiscal environment in which the programm will be carried out. (author). 4 refs, 4 figs

  6. Geospace exploration project: Arase (ERG)

    Science.gov (United States)

    Miyoshi, Y.; Kasaba, Y.; Shinohara, I.; Takashima, T.; Asamura, K.; Matsumoto, H.; Higashio, N.; Mitani, T.; Kasahara, S.; Yokota, S.; Wang, S.; Kazama, Y.; Kasahara, Y.; Yagitani, S.; Matsuoka, A.; Kojima, H.; Katoh, Y.; Shiokawa, K.; Seki, K.; Fujimoto, M.; Ono, T.; ERG project Group

    2017-06-01

    The ERG (Exploration of energization and Radiation in Geospace) is Japanese geospace exploration project. The project focuses on relativistic electron acceleration mechanism of the outer belt and dynamics of space storms in the context of the cross-energy coupling via wave-particle interactions. The project consists of the satellite observation team, the ground-based network observation team, and integrated-data analysis/simulation team. The satellite was launched on December 20 2016 and has been nicknamed, “Arase”. This paper describes overview of the project and future plan for observations.

  7. MEMS applications in space exploration

    Science.gov (United States)

    Tang, William C.

    1997-09-01

    Space exploration in the coming century will emphasize cost effectiveness and highly focused mission objectives, which will result in frequent multiple missions that broaden the scope of space science and to validate new technologies on a timely basis. MEMS is one of the key enabling technology to create cost-effective, ultra-miniaturized, robust, and functionally focused spacecraft for both robotic and human exploration programs. Examples of MEMS devices at various stages of development include microgyroscope, microseismometer, microhygrometer, quadrupole mass spectrometer, and micropropulsion engine. These devices, when proven successful, will serve as models for developing components and systems for new-millennium spacecraft.

  8. Simulation Exploration Experience 2018 Overview

    Science.gov (United States)

    Paglialonga, Stephen; Elfrey, Priscilla; Crues, Edwin Z.

    2018-01-01

    The Simulation Exploration Experience (SEE) joins students, industry, professional associations, and faculty together for an annual modeling and simulation (M&S) challenge. SEE champions collaborative collegiate-level modeling and simulation by providing a venue for students to work in highly dispersed inter-university teams to design, develop, test, and execute simulated missions associated with space exploration. Participating teams gain valuable knowledge, skills, and increased employability by working closely with industry professionals, NASA, and faculty advisors. This presentation gives and overview of the SEE and the upcoming 2018 SEE event.

  9. Interactive Network Exploration with Orange

    Directory of Open Access Journals (Sweden)

    Miha Štajdohar

    2013-04-01

    Full Text Available Network analysis is one of the most widely used techniques in many areas of modern science. Most existing tools for that purpose are limited to drawing networks and computing their basic general characteristics. The user is not able to interactively and graphically manipulate the networks, select and explore subgraphs using other statistical and data mining techniques, add and plot various other data within the graph, and so on. In this paper we present a tool that addresses these challenges, an add-on for exploration of networks within the general component-based environment Orange.

  10. Localization of Alpha-Keratin and Beta-Keratin (Corneous Beta Protein) in the Epithelium on the Ventral Surface of the Lingual Apex and Its Lingual Nail in the Domestic Goose (Anser Anser f. domestica) by Using Immunohistochemistry and Raman Microspectroscopy Analysis.

    Science.gov (United States)

    Skieresz-Szewczyk, Kinga; Jackowiak, Hanna; Buchwald, Tomasz; Szybowicz, Mirosław

    2017-08-01

    The epithelium of the ventral surface of the apex of the tongue in most birds is specified by the presence of the special superficial layer called lingual nail. The aim of the present study is to determine the localization of the alpha-keratin and beta-keratin (corneous beta protein) in this special epithelium in the domestic goose by using immunohistochemistry staining and the Raman spectroscopy analysis. Due to lack of commercially available antibodies to detect beta-keratin (corneous beta protein), the Raman spectroscopy was used as a specific tool to detect and describe the secondary structure of proteins. The immunohistochemical (IHC) detections reveal the presence of alpha-keratin in all layers of the epithelium, but significant differences in the distribution of the alpha-keratin in the epithelial layers appear. The staining reaction is stronger from the basal layer to the upper zone of the intermediate layer. The unique result is weak staining for the alpha-keratin in the lingual nail. Applications of the Raman spectroscopy as a complementary method not only confirmed results of IHC staining for alpha-keratin, but showed that this technique could be used to demonstrate the presence of beta-keratin (corneous beta protein). Functionally, the localization of alpha-keratin in the epithelium of the ventral surface of the lingual apex provides a proper scaffold for epithelial cells and promotes structural integrity, whereas the presence of beta-keratin (corneous beta protein) in the lingual nail, described also as exoskeleton of the ventral surface of the apex, endures mechanical stress. Anat Rec, 300:1361-1368, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  11. Virtual reality and planetary exploration

    Science.gov (United States)

    McGreevy, Michael W.

    Exploring planetary environments is central to NASA's missions and goals. A new computing technology called Virtual Reality has much to offer in support of planetary exploration. This technology augments and extends human presence within computer-generated and remote spatial environments. Historically, NASA has been a leader in many of the fundamental concepts and technologies that comprise Virtual Reality. Indeed, Ames Research Center has a central role in the development of this rapidly emerging approach to using computers. This ground breaking work has inspired researchers in academia, industry, and the military. Further, NASA's leadership in this technology has spun off new businesses, has caught the attention of the international business community, and has generated several years of positive international media coverage. In the future, Virtual Reality technology will enable greatly improved human-machine interactions for more productive planetary surface exploration. Perhaps more importantly, Virtual Reality technology will democratize the experience of planetary exploration and thereby broaden understanding of, and support for, this historic enterprise.

  12. Exploring Water Pollution. Part II

    Science.gov (United States)

    Rillo, Thomas J.

    1975-01-01

    This is part two of a three part article related to the science activity of exploring environmental problems. Part one dealt with background information for the classroom teacher. Presented here is a suggested lesson plan on water pollution. Objectives, important concepts and instructional procedures are suggested. (EB)

  13. Exploring EFL fluency in Asia

    CERN Document Server

    Muller, T; Brown, P; Herder, S

    2014-01-01

    In EFL contexts, an absence of chances to develop fluency in the language classroom can lead to marked limitations in English proficiency. This volume explores fluency development from a number of different perspectives, investigating measurements and classroom strategies for promoting its development.

  14. From space exploration to commercialisation

    NARCIS (Netherlands)

    Tkatchova, S.A.

    2006-01-01

    Space exploration has captured the imagination and dreams of many scientists, engineers and visionaries.The ISS is being built by five ISS partners; NASA, RSA, ESA, CSA and JAXA. ISS commercialisation is the process by which ISS products and services are sold to private companies, without

  15. Risk behavior in petroleum exploration

    International Nuclear Information System (INIS)

    Rose, P.R.

    1992-01-01

    In this paper, the author uses the term risk aversion, which weighs the magnitude of investment against four factors: size of available budget, potential gain, potential loss, and probabilities of each outcome. Modern petroleum exploration consists of a series of investment decisions on whether to acquire additional technical data (geological, geophysical, engineering, drilling, or economic) and/or additional mineral interests. Each decision should allow a progressively clearer perception of project risk versus reward and should support timely management action concerning the inferred accumulation. Companies searching for oil and natural gas make hundreds of such exploration decisions each year. So the problem in serial exploration decision making is twofold: to be consistent in the way we deal with risk and uncertainty and to perceive risk and uncertainty accurately and reduce them where possible. Risk aversion is not just a hypothetical nuisance. It causes explorationists to make inconsistent investment decisions, and it costs exploration companies millions of dollars annually in lost opportunities, bad choices, and wasted investment dollars

  16. Stretching Probability Explorations with Geoboards

    Science.gov (United States)

    Wheeler, Ann; Champion, Joe

    2016-01-01

    Students are faced with many transitions in their middle school mathematics classes. To build knowledge, skills, and confidence in the key areas of algebra and geometry, students often need to practice using numbers and polygons in a variety of contexts. Teachers also want students to explore ideas from probability and statistics. Teachers know…

  17. Lead isotope in mineral exploration

    International Nuclear Information System (INIS)

    Gulson, B.L.

    1986-01-01

    This book provides an up-to-date state-of-the-art review of lead isotopes in mineral exploration. Beginning with an historical review on suggested uses of lead isotopes in mineral exploration, the author then outlines the theoretical aspects of lead isotopes and illustrates that the method is based on well-known principles of radioactive decay, from which isotopic signatures for different styles of mineralization are derived. The varying isotopic signatures are then introduced. The major part of the book details over 40 case histories for base and precious metals, uranium and tin using sampling media such as sulfides, gossans, soils, weathered bedrock, vegetation and groundwaters. Advantages and disadvantages of each are discussed. Examples are given of the use of lead isotopes in testing conceptual models for exploration. The success rate and cost-effectiveness of the method are illustrated by actual exploration examples. Analytical advances which should lower the cost of the method and future uses are outlined. Many of the case histories use recently published or unpublished data, 27 tables of which are given in an appendix. Details of sampling, the methods for obtaining the isotope ratios, and a commercially-available integrated lead isotope service are also provided. (Auth.)

  18. Composites for Exploration Upper Stage

    Science.gov (United States)

    Fikes, J. C.; Jackson, J. R.; Richardson, S. W.; Thomas, A. D.; Mann, T. O.; Miller, S. G.

    2016-01-01

    The Composites for Exploration Upper Stage (CEUS) was a 3-year, level III project within the Technology Demonstration Missions program of the NASA Space Technology Mission Directorate. Studies have shown that composites provide important programmatic enhancements, including reduced weight to increase capability and accelerated expansion of exploration and science mission objectives. The CEUS project was focused on technologies that best advanced innovation, infusion, and broad applications for the inclusion of composites on future large human-rated launch vehicles and spacecraft. The benefits included near- and far-term opportunities for infusion (NASA, industry/commercial, Department of Defense), demonstrated critical technologies and technically implementable evolvable innovations, and sustained Agency experience. The initial scope of the project was to advance technologies for large composite structures applicable to the Space Launch System (SLS) Exploration Upper Stage (EUS) by focusing on the affordability and technical performance of the EUS forward and aft skirts. The project was tasked to develop and demonstrate critical composite technologies with a focus on full-scale materials, design, manufacturing, and test using NASA in-house capabilities. This would have demonstrated a major advancement in confidence and matured the large-scale composite technology to a Technology Readiness Level 6. This project would, therefore, have bridged the gap for providing composite application to SLS upgrades, enabling future exploration missions.

  19. Exploring the Atmosphere Using Smartphones

    Science.gov (United States)

    Monteiro, Martin; Vogt, Patrik; Stari, Cecilia; Cabeza, Cecilia; Marti, Arturo C.

    2016-01-01

    The characteristics of the inner layer of the atmosphere, the troposphere, are determinant for Earth's life. In this experience we explore the first hundreds of meters using a smartphone mounted on a quadcopter. Both the altitude and the pressure are obtained using the smartphone's sensors. We complement these measures with data collected from the…

  20. Life sciences and Mars exploration

    Science.gov (United States)

    Sulzman, Frank M.; Rummel, John D.; Leveton, Lauren B.; Teeter, Ron

    1990-01-01

    The major life science considerations for Mars exploration missions are discussed. Radiation protection and countermeasures for zero gravity are discussed. Considerations of crew psychological health considerations and life support systems are addressed. Scientific opportunities presented by manned Mars missions are examined.