bluuebunny/crossref_metadata_2025 huggingface dataset:
Gluons, Heavy and Light Quarks in the QCD Vacuum
Authors: Musakhanov Mirzayusuf
Published: August 2018

We are discussing the properties of the QCD vacuum which might be important especially for the understanding of hadrons with small quark core size ~ 0:3 fm: We assume that at these distances the QCD vacuum can be described by the Instanton Liquid Model (ILM). At larger distances, where confinement is important, ILM should be extended to Dyons Liquid Model (DLM). The ILM has only two free parameters, average instanton size ρ ≈ 0:3 fm and average inter-instanton distance R ≈ 1 fm, and can successfully describe the key features of light hadron physics. One of the important conceptual results was prediction of the momentum dependent dynamical quark mass M ~ (packing f raction)1/2 ρ-1 ≈ 360 MeV, later confirmed numerically by evaluations in the lattice. The estimates show that gluon-instanton interaction strength is also big and is controlled by the value of dynamical gluon mass Mg ≈ M. Heavy quarks interact with instantons much weaker. The heavy quark-instanton interaction strength is given by ΔmQ ~ packing fraction ρ-1 ≈ 70 MeV: Nevertheless, the direct instanton contribution to the colorless heavy-heavy quarks potential is sizable and must be taken into account. At small distances, where one-gluon exchange contribution to this potential is dominated, we have to take into account dynamical gluon mass Mg. Also, instantons are generating light-heavy quarks interactions and allow to describe the nonperturbative effects in heavy-light quarks systems.
Locality and nonlocality in the interaction-free measurement
Authors: Rohrlich Daniel , Aharonov Yakir , Landsberger Tomer
Published: August 2018

We present a paradox involving a particle and a mirror. They exchange a nonlocal quantity, modular angular momentum Lz mod 2ћ, but there seems to be no local interaction between them that allows such an exchange. We demonstrate that the particle and mirror do interact locally via a weak local current 〈Lz mod 2ћ〉w. In this sense, we transform the “interaction-free measurement” of Elitzur and Vaidman, in which two local quantities (the positions of a photon and a bomb in the two arms of a Mach-Zehnder interferometer) interact nonlocally, into a thought experiment in which two nonlocal quantities (the weak modular angular momentum of the particle and of the mirror) interact locally.
f1(1285) → e+e- decay and direct f1 production in e+e- collisions
Authors: Rudenko A.S.
Published: August 2018

The width of the f1(1285) → e+e+e- decay is calculated in the vector meson dominance model. The result depends on the relative phase between two coupling constants describing f1 → ρ0γ decay. The width Γ( f1 → e+e+e-) is estimated to be ≃ 0:07 - 0:19 eV. Direct f1 production in e+e+e- collisions is discussed, and the e+e+e- → f1 → a0π → ηππ cross section is calculated. Charge asymmetry in the e+e+e- → ηπ+π- reaction due to interference between e+e+e- → f1 and e+e+e- → ηρ0 amplitudes is studied.
The analogy of equation of rotation in complex plane with the Dirac equation, and its foundation
Authors: Sanduk Mohammed
Published: August 2018

The Three Wave Hypothesis (TWH) has been proposed by Horodecki in 1981. Sanduk attributed TWH to a classical kinematical model of two rolling circles in 2007. In a previous project in 2012, it is shown that the position vector of a point in a system of two rolling circles can be transformed to a complex vector under the effect of partial observation. The present work tries to develop this concept of transformation. Under this transformation, it is found that the kinematical equations of the motion of point can be transformed to equations analogise the relativistic quantum mechanics equations. Many analogies have been found and are listed in a comparison table. These analogies may sagest that both of the quantum mechanics and the special relativity are emergent, and are of the same origin.
Self-consistent account for phonon induced corrections to quadrupole moments of odd nuclei. Pole and non-pole diagrams.
Authors: Saperstein E. E. , Kamerdzhiev S. , Krepish D. S. , Tolokonnikov S. V. , Voitenkov D.
Published: August 2018

Recent results of the description of quadrupole moments of odd semi-magic nuclei are briefly reviewed. They are based on the self-consistent theory of finite Fermi systems with account for the phonon-particle coupling (PC) effects. The self-consistent model for describing the PC effects was developed previously for magnetic moments. Account for the non-pole diagrams is an important ingredient of this model. In addition to previously reported results for the odd In and Sb isotopes, which are the proton-odd neighbors of even tin nuclei, we present new results for odd Bi isotopes, the odd neighbors of even lead isotopes. In general, account for the PC corrections makes the agreement with the experimental data significantly better.
Narrow-width tetraquarks in large-Nc QCD
Authors: Lucha Wolfgang , Melikhov Dmitri , Sazdjian Hagop
Published: August 2018

The properties of possibly existing tetraquarks are studied in the large-Nc limit of QCD by means of four-point correlation functions of meson currents. The necessity of a detailed analysis of the singularities of Feynman diagrams, by means of the Landau equations, to recognize those diagrams that might contribute to the formation of tetraquark states, is emphasized. It is found, in general, that tetraquarks, if they exist, should have narrow widths of the order of N-2c.
Form factor decompositions of the QCD four - gluon vertex
Authors: Ahmadiniaz Naser , Schubert Christian
Published: August 2018

The Bern-Kosower formalism, originally developed around 1990 as a novel way of obtaining on-shell amplitudes in field theory as limits of string amplitudes, has recently been shown to be extremely effcient as a tool for obtaining form factor decompositions of the N - gluon vertices. Its main advantages are that gauge invariant structures can be generated by certain systematic integration-by-parts procedures, making unnecessary the usual tedious analysis of the non-abelian off-shell Ward identities, and that the scalar, spinor and gluon loop cases can be treated in a unified way. After discussing the method in general for the N - gluon case, I will show in detail how to rederive the Ball- Chiu decomposition of the three - gluon vertex, and finally present two slightly different decompositions of the four - gluon vertex, one generalizing the Ball Chiu one, the other one closely linked to the QCD effective action.
Predictability analysis of α decay formulae and the α partial half-lives of exotic nuclei
Authors: Dasgupta-Schubert Nabanita
Published: August 2018

We examine the ability of 3 phenomenological alpha decay formulae, the Generalised Liquid Drop Model, the Sobiczewski- Parkhomenko and the Viola-Seaborg-Sobiczewski formulae, to predict the α partial half-lives Tα of 100 exotic alpha radioactive nuclei by the statistical quantification of their accuracy and precision. These quantities were derived using a method based on standard experimental quality assurance wherein the alpha spectroscopic data of 313 well-established alpha decaying nuclei (calibration and test data sets) were used. Experimental masses as well as Finite Range Droplet Model masses were used to compute Qα. Improved coefficients for the three formulae were derived resulting in modified formulae. A simple linear optimization allowed adjustment of the modified formulae for the insufficient statistics of the odd-even and odd-odd decays of the calibration data set, without changing the modified formulae. Relatively better figures of merit for the odd-odd and the SHE were obtained using the modified GLDM formula.
Cosmic matter in the laboratory - the Compressed Baryonic Matter experiment at FAIR
Authors: Senger Peter
Published: August 2018

The Compressed Baryonic Matter (CBM) experiment will be one of the major scientific pillars of the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt. The goal of the CBM research program is to explore the QCD phase diagram in the region of high baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at neutron star core densities, and the search for the deconfinement and chiral phase transitions. The CBM detector is designed to measure rare diagnostic probes such as hadrons including multi-strange (anti-) hyperons, lepton pairs, and charmed particles with unprecedented precision and statistics. Most of these particles will be studied for the first time in the FAIR energy range. In order to achieve the required precision, the measurements will be performed at very high reaction rates of 1 to 10 MHz. This requires very fast and radiation-hard detectors, a novel data read-out and analysis concept based on free streaming front-end electronics, and a high-performance computing cluster for online event selection. The physics program and the status of the proposed CBM experiment will be discussed.
Search for the violation of Pauli Exclusion Principle at LNGS
Authors: Shi H. , Bartalucci S. , Bazzi M. , Bertolucci S. , Bragadireanu A.M. , Cargnelli M. , Clozza A. , Curceanu C. , De Paolis L. , Di Matteo S. , Egger J.-P. , Guaraldo C. , Iliescu M. , Marton J. , Laubenstein M. , Milotti E. , Pichler A. , Pietreanu D. , Piscicchia K. , Scordo A. , Sirghi D.L. , Sirghi F. , Sperandio L. , Vazquez Doce O. , Widmann E. , Zmeskal J. ,   VIP-2 Collaboration
Published: August 2018

In the VIP (VIolation of Pauli exclusion principle) and its follow-up VIP- 2 experiments at the Laboratori Nazionali del Gran Sasso, we test the validity of the Pauli Exclusion Principle, by searching for x-rays from copper atomic transitions from a 2p orbit electron to the ground state which is already occupied by two electrons. Such transitions are prohibited by the Pauli Exclusion Principle. The physics run of the VIP-2 experiment started in late 2016 and will collect data for three years. From the first data taking period of two months we have obtained a new limit better than the VIP result from three years of running. In this article we present the published first physics result from the VIP-2 experiment and discuss about the future perspectives.
Search for rare and exotic Higgs Boson decay modes
Authors: Tao Junquan
Published: August 2018

The latest results in the search for rare and exotic Higgs boson decays in proton-proton collision events collected with the CMS detector at the LHC are presented. The searches are performed for several decay modes of Higgs boson including H → X(X → 2ℓ)γ (X = Z, γ* and ℓ = e, μ), H → μμ=ee, invisible decays, lepton flavour violating decays and Higgs decay to light scalars or pseudo-scalars. No hint for new physics has been found from the analyzed results with the full LHC run-1 data collected during 2011 and 2012 at √s = 7-8 TeV and with the run-2 data at √s = 13 TeV collected during 2015 and 2016. Limits are set for all the searches which have been performed by CMS.
Transverse momentum spectra and nuclear modification factors of identified charged hadrons in p-Pb and Pb-Pb collisions at √sNN = 5.02 TeV with ALICE
Authors: Vasileiou Maria
Published: August 2018

The ALICE experiment has measured the production of identified light-flavour hadrons in p-Pb and Pb-Pb collisions at 5.02 TeV in a wide range of transverse momentum. The newest ALICE results on pion, kaon and proton transverse momentum spectra, yield ratios and nuclear modification factors will be presented and discussed in comparison to lower energy results. In particular, the production of identified hadrons in most central Pb-Pb collisions relative to pp collisions is found to be strongly suppressed at high transverse momenta (pT > 8 GeV/c) whereas in p-Pb collisions the nuclear modification factors are consistent with unity. This indicates that the strong suppression of high-pT hadrons measured in central Pb-Pb collisions is not due to an initial state effect but instead to the energy loss of partons traversing a hot and dense QCD medium.
Understanding X(3862), X(3872), and X(3930) spectrum in a Friedrichs-model-like scheme
Authors: Xiao Zhiguang , Zhou Zhi-Yong
Published: August 2018

In this talk, we review the method we proposed to use the Friedrichs-like model combined with QPC model to include the hadron interaction corrections to the spectrum predicted by the quark model, in particular the Godfrey-Isgur model. This method is then used on the first excited P-wave charmonium states, and X(3862), X(3872), and X(3930) state could be simultaneously produced with a quite good accuracy. The X(3872) state is shown to be a bound state with a large DD* continuum component. At the same time, the hc(2P) state is perdicted at about 3902 MeV with a pole width of about 54 MeV.
Procedure for event characterization in Pb-Pb collisions at 40AGeV in the NA49 experiment at the CERN SPS
Authors: Zherebtsova E. , Klochkov V. , Selyuzhenkov I. , Taranenko A. , Kashirin E.
Published: August 2018

The time evolution of the strongly interacting matter created in a heavy-ion collision depends on the initial geometry and the the centrality of the collision. Thus an experimental determination of the collision geometry is required. This paper discusses a procedure for event classification and estimation of the geometrical parameters in inelastic Pb+Pb collisions at a beam energy of 40A GeV recorded with the fixed target experiment NA49 at the CERN SPS. In the NA49 experiment, event classes can be defined using the measured multiplicity of particles in the Time Projection Chambers (TPC) or the energy of projectile spectators deposited in the forward Veto or Ring calorimeters. Using the Monte-Carlo Glauber model, these event classes can be related to average values of the geometric quantities such as impact parameter or number of nucleon-nucleon collisions. The implementation of this procedure within a software framework of the future CBM experiment was adopted for event classification in the NA49 experiment. In future, this procedure will be used for analysis of the new Pb+Pb data collected by the NA61/SHINE experiment and for comparison with the results previously obtained by STAR at RHIC and NA49 at the CERN SPS.
BESIII future prospects in exotic hadron spectroscopy
Authors: ZHU Kai
Published: August 2018

Recent BESIII results on exotic hadron candidates, the heavy charmonium-like states, will be reviewed, as well as a short introductions to the BEPCII collider and the BEESIII detector. Future BESIII running plans, specially the physics program for the exotic hadron spectroscopy, will be discussed.
Possible Approach to Dynamical Supersymmetry Breaking via Nambu-Jona-Lasinio Model
Authors: Cheng Yifan
Published: August 2018

Supersymmetry is undoubtedly a popular candidate for physics beyond the Standard Model. However, the origin of soft supersymmetry breaking masses has been usually depicted intricately in the literature via extra hidden/mediating sectors. Thus, a simple theory for the generation of the soft masses would be more compelling. Here we discuss a possible approach to dynamical supersymmetry breaking via Nambu-Jona- Lasinio (NJL) Model, which has been missed since the first investigation of supersymmetric NJL model. We introduce a four-superfield interaction term that induces a real two-superfield composite with vacuum condensate. The latter has supersymmetry breaking parts, which we show to bear nontrivial solutions following a standard nonperturbative analysis for a NJL type model. The presence of the expected Goldstino state along with the supersymmetry breaking, is also verified. Moreover, the model gives rise to a composite spin one field, as its important characteristic.
Surrounding matter theory
Authors: Lassiaille Frederic
Published: August 2018

S.M.T. (Surrounding Matter Theory), an alternative theory to dark matter, is presented. It is based on a modification of Newton's law. This modification is done by multiplying a Newtonian potential by a given factor, which is varying with local distribution of matter, at the location where the gravitational force is exerted. With this new equation the model emphasizes that a gravitational force is roughly inversely proportional to mass density at the location where this force is applied. After presentation of the model, its dynamic is quickly applied to cosmology and galaxy structure. Some possible caveats of the model are identified. But the simple mechanism described above suggests the idea of a straightforward solution to the following issues: virial theorem mystery, the bullet cluster (“1E 0657-56” galaxy clusters) issue, the strong relative velocity of its subclusters, the value of cosmological critical density, the fine tuning issue, and expansion acceleration. Nucleosynthesis is not explained and would require a different model for radiation era. But a de Sitter Universe is predicted, this means that the spatial curvature, K, is 0, and today's deceleration parameter, q, is -1. The predicted time since last scattering is 68 h-1Gyr. With this value SMT explains heterogeneities of large scale structure and galaxy formation. Each kind of experimental speed profiles are retrieved by a simulation of a virtual galaxy. In the simulations, ring galaxies are generated by SMT dynamic itself, without the help of any particular external event. Those studies give motivation for scientific comparisons with experimental data.
Nuclear phase transition and thermodynamic instabilities in dense nuclear matter
Authors: Lavagno A.
Published: August 2018

We study the presence of thermodynamic instabilities in a nuclear medium at finite temperature and density where nuclear phase transitions can take place. Such a phase transition is characterized by pure hadronic matter with both mechanical instability (fluctuations on the baryon density) that by chemical-diffusive instability (fluctuations on the electric charge concentration). Similarly to the liquid-gas phase transition, the nucleonic and the Δ-matter phase have a different isospin density in the mixed phase. In the liquid-gas phase transition, the process of producing a larger neutron excess in the gas phase is referred to as isospin fractionation. A similar effects can occur in the nucleon-Δ matter phase transition due essentially to a Δ- excess in the Δ-matter phase in asymmetric nuclear matter. In this context we also discuss the relevance of Δ-isobar and hyperon degrees of freedom in the bulk properties of the protoneutron stars at fixed entropy per baryon, in the presence and in the absence of trapped neutrinos.
Antiproton-nucleus annihilation cross section at low energy
Authors: Aghai–Khozani H. , Bianconi A. , Corradini M. , Hayano R. , Hori M. , Leali M. , Lodi–Rizzini E. , Mascagna V. , Murakami Y. , Prest M. , Vallazza E. , Venturelli L. , Yamada H.
Published: August 2018

The antinucleon-nuclei annihilation cross sections at low energies were systematically measured at CERN in the 80’s and 90’s with the LEAR facility and later with the Antiproton Decelerator. Unfortunately only few data exist for very low energy antiprotons (p<500 MeV/c) on medium and heavy nuclei. A deeper knowledge is required by fundamental physics and can have consequence also in cosmology and medical physics. In order to fill the gap, the ASACUSA Collaboration has very recently measured the annihilation cross section of 100 MeV/c antiprotons on carbon. In the present work the experimental result is presented together with a comparison both with the antineutron data on the same target at the same energies and with the other existing antiproton data at higher energies.
Video capsule endoscopy as a tool for evaluation of obscure overt gastrointestinal bleeding in the intensive care unit
Authors: Hakimian Shahrad , Jawaid Salmaan , Guilarte-Walker Yurima , Mathew Jomol , Cave David
Published: August 2018

Background and study aims Video capsule endoscopy (VCE) is a minimally invasive tool that helps visualize the gastrointestinal tract from the esophagus to the right colon without the need for sedation or preparation. VCE is safe with very few contraindications. However, its role and safety profile in the intensive care unit (ICU) population have not been reported. The aim of this study is to evaluate the safety, efficacy, and feasibility of VCE use in ICU patients.

Patients and methods We conducted a single-center retrospective observational study of patients who underwent VCE for evaluation of obscure overt gastrointestinal bleeding in the ICU between 2008 and 2016.

Results This study included 48 patients who were admitted to the UMass Memorial Medical Center ICUs for gastrointestinal bleeding. VCE was successfully completed in 43/48 (90 %) patients. The entire length of small bowel could be evaluated in 75 % and the source of bleeding was identified in 44 % of the patients. The most commonly identified source of bleeding included small bowel angioectasias, duodenal erosions/ulcers, and small bowel polyps. No major complications could be attributed to the VCE. Only 1 capsule was retained after 2 wk; however, there was no incidence of bowel obstruction, perforation, or capsule aspiration.

Conclusions This observational retrospective study demonstrates that VCE may be a safe, feasible, and effective diagnostic tool in evaluation of gastrointestinal bleeding in the ICU population with few complications. VCE may be a safe diagnostic prelude and be a guide to the correct therapeutic procedure if needed, in the context of patients who are seriously ill.
Zerebrale Mikroangiopathien
Authors: Düring Marco , Opherk Christian
Published: August 2018

Zerebrale Mikroangiopathien, Erkrankungen der kleinen Gefäße (perforierende Arterien und Arteriolen, Kapillaren, Venolen) des Gehirns, sind häufige Ursachen von Schlaganfall und vaskulärer Demenz. Die häufigste Form ist alters- und hypertonieassoziiert, die genauen Pathomechanismen sind jedoch weitgehend unbekannt. Weitere relevante Formen sind die zerebrale Amyloidangiopathie und monogen vererbte Mikroangiopathien, wie bspw. CADASIL als häufigste erbliche Schlaganfallerkrankung. An klinischen Manifestationen finden sich akute (ischämischer oder hämorrhagischer Schlaganfall) und chronische Symptome. Zu letzteren zählen eine Gangstörung, affektive Symptome und eine vaskuläre kognitive Störung mit Defiziten vorwiegend im Bereich der Exekutivfunktionen. In der MRT finden sich charakteristische Gewebeläsionen, u. a. konfluierende T2-Hyperintensitäten (Leukenzephalopathie), Lakunen, Mikroblutungen und kortikale Mikroinfarkte. Zudem kommt es im Verlauf zu einer Gehirnatrophie. Differenzialdiagnostisch müssen die verschiedenen Formen der Mikroangiopathie voneinander abgegrenzt werden, da dies ggf. therapeutische Konsequenzen hat. Ferner stellen entzündliche ZNS-Erkrankungen und Leukodystrophien mögliche Differenzialdiagnosen dar. Therapeutisch steht die Optimierung des Gefäßrisikoprofils im Vordergrund.
A new experimental method based on volume measurement for determining axial scaling during breakup of drops and liquid threads
Authors: Wagoner Brayden W. , Thete Sumeet S. , Basaran Osman A.
Published: August 2018

Thread breakup is ubiquitous in drop formation. As liquid threads thin, monitoring the time variation of the thread’s minimum radius hmin and the axial extent of the pinching zone z′ can help decipher the balance of forces governing breakup. The variation of hmin with time from pinch-off, τ ≡ tb − t (t is time; tb is breakup time)—radial scaling—can be determined experimentally from images of drops forming from a nozzle. Thus, all previous experimental studies report radial scaling, viz., hmin ∼ τa (a is the radial scaling exponent). Determination of axial scaling or how z′ varies with τ, z′ ∼ τb (b is the axial scaling exponent), however, is not as straightforward and hence rarely reported. Experimental determination of axial scaling is made difficult because thinning threads can be long and slender, and hence data on time evolution of z′ can be noisy. Moreover, inference of z′ from experiments can be challenging in situations involving suspension drops containing non-Brownian particles where particles can partially protrude out of the interface. We present a new way of determining axial scaling by experimental measurement of the time variation of the volume of the pinching zone and inferring z′ from volume measurements. The accuracy of the new method is tested by new experiments in which the scalings are determined during dripping of Newtonian liquids and are shown to be in excellent accord with scaling predictions and transitions between different regimes predicted from theory and simulation.
Control of haze value by dynamic scattering in a liquid crystal mixture without ion dopants
Authors: Jo Young-Seo , Choi Tae-Hoon , Ji Seong-Min , Yoon Tae-Hoon
Published: August 2018

We report a method to control the haze value by dynamic scattering in a liquid crystal mixture without ion dopants. The liquid crystal (LC) mixture consists of chiral smectic C (SmC*) and nematic (N) LC molecules. In the absence of an electric field, LC molecules in the SmC* phase are oriented by the neighboring vertically-aligned N-LC molecules so that the LC cell is transparent. When a vertical electric field is applied to the LC cell, N-LC molecules with negative dielectric anisotropy tilt down in a random direction parallel to the two substrates, whereas SmC*-LC molecules are rotated with the polarity reversal of the applied field. During the switching process, we observed dynamic scattering because the random orientation of N-LCs is maintained via the rotation of SmC*-LCs, resulting in a high-haze translucent state without the use of ionic dopants. The LC mixture exhibited a very high haze of 96.1% in the translucent state while maintaining the haze-free (<1%) transparent state owing to the use of an LC layer without a polymer structure.
Deformation of dark solitons in a PT-invariant variable coefficients nonlocal nonlinear Schrödinger equation
Authors: Manikandan K. , Vishnu Priya N. , Senthilvelan M. , Sankaranarayanan R.
Published: August 2018

We derive dark and antidark soliton solutions of a parity-time reversal (PT)-invariant variable coefficients nonlocal nonlinear Schrödinger (NNLS) equation. We map the considered equation into a defocusing PT-invariant NNLS equation with a constraint between dispersion, nonlinearity, and gain/loss parameters. We show that the considered system is PT-invariant only when the dispersion and nonlinearity coefficients are even functions and gain/loss coefficient is an odd function. The characteristics of the constructed dark soliton solutions are investigated with four different forms of dispersion parameters, namely, (1) constant, (2) periodically distributed, (3) exponentially distributed, and (4) periodically and exponentially distributed dispersion parameter. We analyze in detail how the nonlocal dark soliton profiles get deformed in the plane wave background with these dispersion parameters.
Apparatus and method for the growth of epitaxial complex oxides on native amorphous SiO2 surface of (001) oriented single crystal silicon
Authors: Padhan Prahallad , Sinha Umesh Kumar , Sahoo Antarjami
Published: August 2018

The design, fabrication, and performance of an apparatus for the deposition of complex oxides with highly uniform thicknesses at controllable deposition rates over large area, even on the native amorphous SiO2 layer of (001) oriented single crystal Si, are described. The apparatus makes use of the lateral port of a spherical chamber. The port is maintained at uniform temperature, and it houses a substrate heater. The deposition process is controlled by varying different parameters such as target-to-substrate distance, sputtering power, sputtering gas atmosphere, substrate temperature, and pulsed plasma growth. The system has been tested by growing a series of La0.7Sr0.3MnO3 thin films on Si. The systematic strain relaxation and thus the tunable magnetic properties along with the presence of high-quality surface morphology of the films indicate that the designed system could be used to fabricate different components of oxide electronics-based devices over larger area.
Overcoming sheaths overlapping in a small diameter metallic tube with one end closed and using a high density plasma from a high power pulsed hollow cathode discharge
Authors: Ueda M. , Silva C. , de Souza G. B. , Mariano S. F. M. , Pichon L.
Published: August 2018

High voltage sheaths are formed when plasmas are produced by application of high negative voltage pulses to conductive supports or components, as in Plasma Immersion Ion Implantation (PIII) treatments of materials surfaces. For parts with concave shape, as inside metal tubes, these sheaths behave quite differently according to the tube configuration and size, as well as, PIII treatment pressure of operation and pulsing parameters. In this work, an SS304 tube of 1.1 cm internal diameter and 20 cm length was pulsed typically at -0.5 to -2.6 kV, 20 μs pulse length, 500 Hz repetition rate, nitrogen pressure of 5x10-2 mbar and with one side closed configuration. Different currents (between 10 and 30 A) were used to produce plasmas with sheaths that overlapped or not, depending on the currents used. To study these sheath behaviors, a simple plasma diagnostic technique based on a bi-dimensional mapping of the deposition of sputtered materials and by etching via the plasma on a Si wafer target surface, both coming out from the tube, was used. This mapping showed clearly the border line situation between overlapping and non-overlapping sheaths in that small tube which allowed to estimate the plasma density to be around 1011 cm-3 at such a sheath condition, as previously anticipated by Sheridan. Above that border condition, nitrogen PIII was successfully obtained in such a small tube of SS304, producing TiN and Ti2N in samples of Ti6Al4V placed inside the tube, when temperatures higher than 800°C were reached there. Below the border, no significant uptake of nitrogen was possible. Using this type of experimental set-up, it is now possible to explore different hollow cathode behaviors, efficient or high temperature (above 800°C) PIII conditions and also new utilizations of the plasma ejected from the tube.
Mean-field density functional theory of a nanoconfined classical, three-dimensional Heisenberg fluid. II. The interplay between molecular packing and orientational order
Authors: Wandrei Stefanie M. , Roth Roland , Schoen Martin
Published: August 2018

As in Paper I of this series of papers [S. M. Cattes et al., J. Chem. Phys. 144, 194704 (2016)], we study a Heisenberg fluid confined to a nanoscopic slit pore with smooth walls. The pore walls can either energetically discriminate specific orientations of the molecules next to them or are indifferent to molecular orientations. Unlike in Paper I, we employ a version of classical density functional theory that allows us to explicitly account for the stratification of the fluid (i.e., the formation of molecular layers) as a consequence of the symmetry-breaking presence of the pore walls. We treat this stratification within the White Bear version (Mark I) of fundamental measure theory. Thus, in this work, we focus on the interplay between local packing of the molecules and orientational features. In particular, we demonstrate why a critical end point can only exist if the pore walls are not energetically discriminating specific molecular orientations. We analyze in detail the positional and orientational order of the confined fluid and show that reorienting molecules across the pore space can be a two-dimensional process. Last but not least, we propose an algorithm based upon a series expansion of Bessel functions of the first kind with which we can solve certain types of integrals in a very efficient manner.
A subwavelength asymmetric acoustic design for waveform-preserved highly forward transmission
Authors: Zhang Sai , Xu Baiqiang , Hu Guanghua , Cui Sen , He Huizi , Cao Wenwu
Published: August 2018

We propose a subwavelength acoustic asymmetric transmission (SAAT) design constituting of a solid-fluid superlattice (SFSL) coupled with an acoustic grating (AG), which can provide waveform-preserved transmission with very high forward transmission and nearly forbidden backward transmission. The unique feature of waveform preservation of the transmission wave is attributed to the low-frequency diffraction characteristics of the AG together with the extraordinary forbidden transmission of SFSL in a broadband frequency range. Both the frequency range and the beam direction of the transmission wave calculated by using finite element method agree perfectly with the analytical predictions. By investigating the influence of several key parameters, including the angular orientation of the AG unit and the periodicity number of the SFSL, we were able to optimize the SAAT device design, which can increase the energy forward transmission up to 60% without waveform distortion, and the reverse transmission is nearly forbidden. Such remarkable features of our SAAT make this design favorable in unidirectional signal transmission applications.
Resistivity reduction of low temperature grown p-Al0.09Ga0.91N by suppressing the incorporation of carbon impurity
Authors: Liang F. , Yang Jing , Zhao D. G. , Jiang D. S. , Liu Z. S. , Zhu J. J. , Chen P. , Liu S. T. , Xing Y. , Zhang L. Q. , Wang W. J. , Li Mo , Zhang Y. T. , Du G. T.
Published: August 2018

Reducing the resistivity of low temperature grown p-Al0.09Ga0.91N layers is crucial to improving the performance of GaN-based laser diodes. In this study, growth conditions of low temperature grown p-Al0.09Ga0.91N layers are monitored and the role of C impurity is investigated systematically. On the basis of the dependence of resistivity on C concentration and the photoluminescence analysis, it is found that C impurities act as donors in p-Al0.09Ga0.91N layer, and reducing the C concentration can reduce its compensation effect on Mg acceptor. Finally, a low resistivity of 4.2 Ω·cm is achieved for the low temperature grown p-Al0.09Ga0.91N.
Propelled microparticle hydrodynamics model developed for non-Newtonian fluids
Authors: DeJarnette Drew
Published: August 2018

New numerical model for the hydrodynamic behavior of squirmers in shear-thickening, -thinning, and -independent fluids developed and verified for microparticulate or microorganism motion.
Population monitoring and habitat utilisation of the ash-grey mouse (Pseudomys albocinereus) in Western Australia
Authors: Smith K. J. , Fleming P. A. , Kreplins T. L. , Wilson B. A.
Published: August 2018

Although Australia has a diverse native rodent fauna, the population dynamics and habitat requirements of most species have not yet been identified. Effective management for conservation of these species is therefore hindered. The aim of the present study was to investigate the habitat use and population dynamics of the ash-grey mouse (Pseudomys albocinereus) through trapping and radio-tracking in Boonanarring Nature Reserve, Western Australia. Although there was no relationship between capture rate and time since fire, ash-grey mice selected dense understorey vegetation. Burrows (47% of 19 unique daytime locations), Xanthorrhoea spp. (26%), tree hollows (11%), shrubs (11%), and logs were selected as daytime refuges. Mean (±s.e.) short-term home-range size was 1.70±0.97ha (n=9) (maximum=9.15ha). There was some evidence that ash-grey mice may be excluded from favourable habitat by a high abundance of house mice (Mus musculus). Management to prevent declines of ash-grey mice should minimise threats to significant habitat features – areas with dense understorey vegetation, soils suitable for burrowing, grasstrees, hollow logs, and tree hollows. Suitable management strategies include: retention or rehabilitation of remnant vegetation; exclusion of livestock; low-intensity, small-area burns; and control of weeds, introduced predators and Phytophthora cinnamomi.
Electrically induced 2D half-metallic antiferromagnets and spin field effect transistors
Authors: Gong Shi-Jing , Gong Cheng , Sun Yu-Yun , Tong Wen-Yi , Duan Chun-Gang , Chu Jun-Hao , Zhang Xiang
Published: August 2018

Significance

When conduction electrons in a solid are completely spin polarized, the single-spin transport results in great promise in spintronic (i.e., spin electronic) applications. Realizing high-efficiency spintronic devices based on 2D van der Waals (vdW) materials would tremendously impact nanoscale spintronics and the current information technologies. However, a minority of vdW materials are magnetic, among which antiferromagnets do not have net spin polarization whereas ferromagnets usually have limited imbalance between oppositely polarized electrons. Here, we show that antiferromagnetic vdW bilayers can be made half metallic, in which electrons of singular spin are metallic but those of the opposite spin are insulating, leading to 100% spin-polarized conduction electrons. Based on this finding, an interesting type of spin field effect transistor is proposed.
A new puzzle about belief and credence
Authors: Moon Andrew
Published: August 2018

I present a puzzle about belief and credence, which takes the form of three independently supported views that are mutually inconsistent. The first is the view thatShas a modal belief thatp(e.g.,Sbelieves that probably-p) if and only ifShas a corresponding credence thatp. The second is the view thatSbelieves thatponly ifShas some credence thatp. The third is the view that, possibly,Sbelieves thatpwithout a modal belief thatp. [Word Count: 85]
RETRACTED: Research on Application of Artificial Intelligence Based on Big Data Background in Computer Network Technology
Authors: Yang Lin
Published: August 2018

In recent years, science and technology have developed rapidly, information data has grown rapidly and society has entered the era of big data. Big data contains enormous economic, social, scientific values and has become the focus of attention of all walks of life. Many scholars have invested in the research of big data. Computer network technology has changed people’s lifestyles, provided convenience for human life and developed toward the direction of artificial intelligence. Artificial intelligence technology improves the performance and effectiveness of computer network technology. This article takes artificial intelligence in the background of big data era as the research object, exploreing its application in computer network technology, which provides some reference significance for the research and application of artificial intelligence in computer network technology.
Trends in Poliovirus Seroprevalence in Kano State, Northern Nigeria
Authors: Verma Harish , Iliyasu Zubairu , Craig Kehinde T , Molodecky Natalie A , Urua Utibeabasi , Jibir Binta Wudil , Gwarzo Garba Dayyabu , Gajida Auwalu U , McDonald Sharla , Weldon William C , Oberste M Steven , Braka Fiona , Mkanda Pascal , Sutter Roland W
Published: August 2018

Background

Kano state has been a protracted reservoir of poliovirus in Nigeria. Immunity trends have been monitored through seroprevalence surveys since 2011. The survey in 2015 was, in addition, intended to assess the impact of use of inactivated poliovirus vaccine (IPV).

Methods

It was a health facility based seroprevalence survey. Eligible children aged 6-9, 12-15 and 19-22 months of age brought to the paediatrics outpatient department of Murtala Mohammad Specialist Hospital between 19 October and 6 November 2015, were screened for eligibility. Eligible children were enrolled after parental consent, history taken, physical examination conducted, and a blood sample collected to test for neutralizing antibody titres against the three poliovirus serotypes.

Results

Overall, 365 results were available in the three age groups. In the 6-9-month-old age group, the seroprevalence was 73% (95% confidence interval [CI] 64-80%), 83% (95% CI 75-88%), and 66% (95% CI 57-73%) for serotypes 1, 2, and 3, respectively. In the 12-15- and 19-22-month-old age groups, seroprevalence was higher but still remained <90% across serotypes. Seroprevalence to serotypes 1 and 3 in 2015 was similar to 2014; however, for serotype 2 there was a significant improvement. IPV received in supplemental immunization activities was found to be a significant predictor of seropositivity among 6-9-month-old infants for serotypes 1 and 2.

Conclusions

Seroprevalence for serotypes 1 and 3 remains low (<80%) in 6-9-month-olds. This poses a significant risk for poliovirus spread if reintroduced into the population. Efforts to strengthen immunization coverage are imperative to secure and sustain high population immunity.
Exact solutions of infinite dimensional total-variation regularized problems
Authors: Flinth Axel , Weiss Pierre
Published: August 2018

We study the solutions of infinite dimensional inverse problems over Banach spaces. The regularizer is defined as the total variation of a linear mapping of the function to recover, while the data fitting term is a near arbitrary function. The first contribution describes the solution’s structure: we show that under mild assumptions, there always exists an $m$-sparse solution, where $m$ is the number of linear measurements of the signal. Our second contribution is about the computation of the solution. While most existing works first discretize the problem, we show that exact solutions of the infinite dimensional problem can be obtained by solving one or two consecutive finite dimensional convex programs depending on the measurement functions structures. We finish by showing an application on scattered data approximation. These results extend recent advances in the understanding of total-variation regularized inverse problems.
Overview of quality management models for inpatient healthcare settings. A scoping review
Authors: Maritz Roxanne , Scheel-Sailer Anke , Schmitt Klaus , Prodinger Birgit
Published: August 2018

Purpose

This scoping review aimed to generate an overview of existing quality management (QM) models for inpatient healthcare published in peer-reviewed literature.

Data sources

Peer-reviewed publications published until June 2016 were retrieved from the databases Medline, PubMed, CINAHL and Cochrane Library using search terms related to QM and models.

Study selection

Publications mentioning a QM model for general application in healthcare or inpatient care in their title or abstract were included. Languages considered were: English, French, German, Italian and Spanish.

Data extraction

Data extraction was 3-fold. First, publication characteristics were summarized. Second, the frequency of each identified model was documented and the publications were divided into conceptual and implementation publications. Third, relevant QM models were identified and information regarding the model, including content and relationship with other models, was extracted.

Results of data synthesis

Of 925 retrieved publications, 213 were included. The included publications reported on 64 different QM models that were suitable for or used in inpatient care. Seventeen models were identified as being relevant. The 17 models were then categorized into three different levels: conceptual quality improvement models, concrete application models and country specific adaptations.

Conclusion

This scoping review provides an overview of 17 existing QM models for inpatient care and their relationships with each other. Various types of models with differing aspects and components exist. In searching for QM models, many different concepts like QM system, accreditation or methodologies appeared. For future investigation, concepts of interest should be clarified.
Viral Etiology of Acute Gastroenteritis in <2-Year-Old US Children in the Post–Rotavirus Vaccine Era
Authors: Hassan Ferdaus , Kanwar Neena , Harrison Christopher J , Halasa Natasha B , Chappell James D , Englund Janet A , Klein Eileen J , Weinberg Geoffrey A , Szilagyi Peter G , Moffatt Mary E , Oberste M Steven , Nix William A , Rogers Shannon , Bowen Michael D , Vinjé Jan , Wikswo Mary E , Parashar Umesh D , Payne Daniel C , Selvarangan Rangaraj
Published: August 2018

Background

The rotavirus disease burden has declined substantially since rotavirus vaccine was introduced in the United States in 2006. The aim of this study was to determine the viral etiology of acute gastroenteritis (AGE) in US children aged <2 years.

Methods

The New Vaccine Surveillance Network (NVSN) of geographically diverse US sites conducts active pediatric population-based surveillance in hospitals and emergency departments. Stool samples were collected from children aged <2 years with symptoms of AGE (n = 330) and age-matched healthy controls (HCs) (n = 272) between January and December 2012. Samples were tested by real-time reverse-transcriptase polymerase chain reaction assays {adenovirus (type 40 and 41), norovirus, parechovirus A, enterovirus, sapovirus, and astrovirus} and an enzyme immunoassay (rotavirus). All samples that tested positive were genotyped.

Results

Detection rates of pathogens in children with AGE versus those of HCs were, respectively, 23.0% versus 6.6% for norovirus (P < .01), 23.0% versus 16.0% for adenovirus (P = .08), 11.0% versus 16.0% for parechovirus A (P = .09), 11.0% versus 9.0% for enterovirus (P = .34), 7.0% versus 3.0% for sapovirus (P = .07), 3.0% versus 0.3% for astrovirus (P = .01), and 3.0% versus 0.4% for rotavirus (P = .01). A high prevalence of adenovirus was detected at 1 surveillance site (49.0% for children with AGE and 43.0% for HCs). Norovirus GII.4 New Orleans was the most frequently detected (33.0%) norovirus genotype. Codetection of >1 virus was more common in children with AGE (16.0%) than in HCs (10.0%) (P = .03).

Conclusions

Norovirus, astrovirus, sapovirus, and rotavirus were detected significantly more in children with AGE than in HCs, and norovirus was the leading AGE-causing pathogen in US children aged <2 years during the year 2012.
A sextet of clusters in the Vela OB2 region revealed by Gaia
Authors: Beccari Giacomo , Boffin Henri M J , Jerabkova Tereza , Wright Nicholas J , Kalari Venu M , Carraro Giovanni , De Marchi Guido , de Wit Willem-Jan
Published: August 2018

Using Gaia DR2 data, combined with OmegaCAM ground-based optical photometry from the Accretion Disc with OmegaCAM survey, and detailed radial velocity measurements from ESO-Gaia, we analyse in detail a 10 × 5 deg region around the Wolf–Rayet Star γ2 Vel, including the previously known clusters Gamma Vel and NGC2547. Using clustering analysis that considers positions, proper motions, and parallax, we discover six clusters or associations – four of which appear new. Analysis of the colour–magnitude diagram for these clusters shows that four of them formed coevally from the same molecular clouds 10 Myr ago, while NGC 2547 formed together with a newly discovered cluster 30 Myr ago. This study shows the incredible wealth of data provided by Gaia for the study of young stellar clusters.