bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Dark Vortex on Neptune
Authors: Wong Michael H. , Tollefson Joshua , Hsu Andrew I. , Pater Imke de , Simon Amy A. , Hueso Ricardo , Sánchez-Lavega Agustín , Sromovsky Lawrence , Fry Patrick , Luszcz-Cook Statia , Hammel Heidi , Delcroix Marc , Kleer Katherine de , Orton Glenn S. , Baranec Christoph
Published: February 2018

An outburst of cloud activity on Neptune in 2015 led to speculation about whether the clouds were convective in nature, a wave phenomenon, or bright companions to an unseen dark vortex (similar to the Great Dark Spot studied in detail by Voyager 2). The Hubble Space Telescope (HST) finally answered this question by discovering a new dark vortex at 45 degrees south planetographic latitude, named SDS-2015 for “southern dark spot discovered in 2015.” SDS-2015 is only the fifth dark vortex ever seen on Neptune. In this paper, we report on imaging of SDS-2015 using HST’s Wide Field Camera 3 across four epochs: 2015 September, 2016 May, 2016 October, and 2017 October. We find that the size of SDS-2015 did not exceed 20 degrees of longitude, more than a factor of two smaller than the Voyager dark spots, but only slightly smaller than previous northern-hemisphere dark spots. A slow (1.7–2.5 deg/year) poleward drift was observed for the vortex. Properties of SDS-2015 and its surroundings suggest that the meridional wind shear may be twice as strong at the deep level of the vortex as it is at the level of cloud-tracked winds. Over the 2015–2017 period, the dark spot’s contrast weakened from about

to about

, while companion clouds shifted from offset to centered, a similar evolution to some historical dark spots. The properties and evolution of SDS-2015 highlight the diversity of Neptune’s dark spots and the need for faster cadence dark spot observations in the future.
The Radial Velocity Variability of the K-giant γ Draconis: Stellar Variability Masquerading as a Planet
Authors: Hatzes A. P. , Endl M. , Cochran W. D. , MacQueen P. J. , Han I. , Lee B.-C. , Kim K.-M. , Mkrtichian D. , Döllinger M. , Hartmann M. , Karjalainen M. , Dreizler S.
Published: February 2018

We present precise stellar radial velocity (RV) measurements of γ Dra taken from 2003 to 2017. The data from 2003 to 2011 show coherent, long-lived variations with a period of 702 days. These variations are consistent with the presence of a planetary companion having m sin i = 10.7 M
Jup whose orbital properties are typical for giant planets found around evolved stars. An analysis of the Hipparcos photometry, Ca ii S-index measurements, and measurements of the spectral line shapes during this time show no variations with the RV of the planet, which seems to “confirm” the presence of the planet. However, RV measurements taken from 2011–2017 seem to refute this. From 2011–2013, the RV variations virtually disappear, only to return in 2014 but with a noticeable phase shift. The total RV variations are consistent either with amplitude variations on timescales of ≈10.6 year, or the beating effect between two periods of 666 and 801 days. It seems unlikely that both these signals stem from a two-planet system. A simple dynamical analysis indicates that there is only a 1%–2% chance that the two-planet system is stable. Rather, we suggest that this multi-periodic behavior may represent a new form of stellar variability, possibly related to oscillatory convective modes. If such intrinsic stellar variability is common around K giant stars and is attributed to planetary companions, then the planet occurrence rate among these stars may be significantly lower than thought.
Diffusive Tidal Evolution for Migrating Hot Jupiters
Authors: Wu 武延 Yanqin 庆
Published: February 2018

I consider a Jovian planet on a highly eccentric orbit around its host star, a situation produced by secular interactions with its planetary or stellar companions. The tidal interactions at every periastron passage exchange energy between the orbit and the planet’s degree-2 fundamental-mode. Starting from zero energy, the f-mode can diffusively grow to large amplitudes if its one-kick energy gain is ≥10−5 of the orbital energy. This requires a pericenter distance of ≤4 tidal radii (or 1.6 Roche radii). If the f-mode has a non-negligible initial energy, diffusive evolution can occur at a lower threshold. The first effect can stall the secular migration as the f-mode can absorb orbital energy and decouple the planet from its secular perturbers, parking all migrating jupiters safely outside the zone of tidal disruption. The second effect leads to rapid orbit circularization as it allows an excited f-mode to continuously absorb orbital energy as the orbit eccentricity decreases. So without any explicit dissipation, other than the fact that the f-mode will damp nonlinearly when its amplitude reaches unity, the planet can be transported from a few au to ∼0.2 au in ∼104 years. Such a rapid circularization is equivalent to a dissipation factor Q ∼ 1, and it explains the observed deficit of super-eccentric Jovian planets. Lastly, the repeated f-mode breaking likely deposits energy and angular momentum in the outer envelope and avoids thermally ablating the planet. Overall, this work boosts the case for hot Jupiter formation through high-eccentricity secular migration.
A Model for the Onset of Self-gravitation and Star Formation in Molecular Gas Governed by Galactic Forces. I. Cloud-scale Gas Motions
Authors: Meidt Sharon E. , Leroy Adam K. , Rosolowsky Erik , Kruijssen J. M. Diederik , Schinnerer Eva , Schruba Andreas , Pety Jerome , Blanc Guillermo , Bigiel Frank , Chevance Melanie , Hughes Annie , Querejeta Miguel , Usero Antonio
Published: February 2018

Modern extragalactic molecular gas surveys now reach the scales of star-forming giant molecular clouds (GMCs; 20–50 pc). Systematic variations in GMC properties with galaxy environment imply that clouds are not universally self-gravitating objects, decoupled from their surroundings. Here we re-examine the coupling of clouds to their environment and develop a model for 3D gas motions generated by forces arising with the galaxy gravitational potential defined by the background disk of stars and dark matter. We show that these motions can resemble or even exceed the motions needed to support gas against its own self-gravity throughout typical galactic disks. The importance of the galactic potential in spiral arms and galactic centers suggests that the response to self-gravity does not always dominate the motions of gas at GMC scales, with implications for observed gas kinematics, virial equilibrium, and cloud morphology. We describe how a uniform treatment of gas motions in the plane and in the vertical direction synthesizes the two main mechanisms proposed to regulate star formation: vertical pressure equilibrium and shear/Coriolis forces as parameterized by Toomre Q ≈ 1. As the modeled motions are coherent and continually driven by the external potential, they represent support for the gas that is distinct from that conventionally attributed to turbulence, which decays rapidly and thus requires maintenance, e.g., via feedback from star formation. Thus, our model suggests that the galaxy itself can impose an important limit on star formation, as we explore in a second paper in this series.
The Einstein@Home Gamma-ray Pulsar Survey. II. Source Selection, Spectral Analysis, and Multiwavelength Follow-up
Authors: Wu J. , Clark C. J. , Pletsch H. J. , Guillemot L. , Johnson T. J. , Torne P. , Champion D. J. , Deneva J. , Ray P. S. , Salvetti D. , Kramer M. , Aulbert C. , Beer C. , Bhattacharyya B. , Bock O. , Camilo F. , Cognard I. , Cuéllar A. , Eggenstein H. B. , Fehrmann H. , Ferrara E. C. , Kerr M. , Machenschalk B. , Ransom S. M. , Sanpa-Arsa S. , Wood K.
Published: February 2018

We report on the analysis of 13 gamma-ray pulsars discovered in the Einstein@Home blind search survey using Fermi Large Area Telescope (LAT) Pass 8 data. The 13 new gamma-ray pulsars were discovered by searching 118 unassociated LAT sources from the third LAT source catalog (3FGL), selected using the Gaussian Mixture Model machine-learning algorithm on the basis of their gamma-ray emission properties being suggestive of pulsar magnetospheric emission. The new gamma-ray pulsars have pulse profiles and spectral properties similar to those of previously detected young gamma-ray pulsars. Follow-up radio observations have revealed faint radio pulsations from two of the newly discovered pulsars and enabled us to derive upper limits on the radio emission from the others, demonstrating that they are likely radio-quiet gamma-ray pulsars. We also present results from modeling the gamma-ray pulse profiles and radio profiles, if available, using different geometric emission models of pulsars. The high discovery rate of this survey, despite the increasing difficulty of blind pulsar searches in gamma rays, suggests that new systematic surveys such as presented in this article should be continued when new LAT source catalogs become available.
Resonant Inverse Compton Scattering Spectra from Highly Magnetized Neutron Stars
Authors: Wadiasingh Zorawar , Baring Matthew G. , Gonthier Peter L. , Harding Alice K.
Published: February 2018

Hard, nonthermal, persistent pulsed X-ray emission extending between 10 and ∼150 keV has been observed in nearly 10 magnetars. For inner-magnetospheric models of such emission, resonant inverse Compton scattering of soft thermal photons by ultrarelativistic charges is the most efficient production mechanism. We present angle-dependent upscattering spectra and pulsed intensity maps for uncooled, relativistic electrons injected in inner regions of magnetar magnetospheres, calculated using collisional integrals over field loops. Our computations employ a new formulation of the QED Compton scattering cross section in strong magnetic fields that is physically correct for treating important spin-dependent effects in the cyclotron resonance, thereby producing correct photon spectra. The spectral cutoff energies are sensitive to the choices of observer viewing geometry, electron Lorentz factor, and scattering kinematics. We find that electrons with energies ≲15 MeV will emit most of their radiation below 250 keV, consistent with inferred turnovers for magnetar hard X-ray tails. More energetic electrons still emit mostly below 1 MeV, except for viewing perspectives sampling field-line tangents. Pulse profiles may be singly or doubly peaked dependent on viewing geometry, emission locale, and observed energy band. Magnetic pair production and photon splitting will attenuate spectra to hard X-ray energies, suppressing signals in the Fermi-LAT band. The resonant Compton spectra are strongly polarized, suggesting that hard X-ray polarimetry instruments such as X-Calibur, or a future Compton telescope, can prove central to constraining model geometry and physics.
Electron-density-sensitive Line Ratios of Fe xiii– xvi from Laboratory Sources Compared to CHIANTI
Authors: Weller M. E. , Beiersdorfer P. , Soukhanovskii V. A. , Scotti F. , LeBlanc B. P.
Published: February 2018

We present electron-density-sensitive line ratios for Fe xiii– xvi measured in the spectral wavelength range of 200–440 Å and an electron density range of (1–4) × 1013 cm−3. The results provide a test at the high-density limit of density-sensitive line ratios useful for astrophysical studies. The measurements were performed on the National Spherical Torus Experiment-Upgrade, where electron densities were measured independently by the laser Thomson scattering diagnostic. Spectra were collected with a flat-field grazing-incidence spectrometer, which provided a spectral resolution of up to 0.3 Å, i.e., high resolution across the broad wavelength range. The response of the instrument was relatively calibrated using spectroscopic techniques in order to improve accuracy. The line ratios are compared to other laboratory sources and the latest version of CHIANTI (8.0.2), and an agreement within 30% is found.
Chemical and Physical Picture of IRAS 16293–2422 Source B at a Sub-arcsecond Scale Studied with ALMA
Authors: Oya Yoko , Moriwaki Kana , Onishi Shusuke , Sakai Nami , López–Sepulcre Ana , Favre Cécile , Watanabe Yoshimasa , Ceccarelli Cecilia , Lefloch Bertrand , Yamamoto Satoshi
Published: February 2018

We have analyzed the OCS, H2CS, CH3OH, and HCOOCH3 data observed toward the low-mass protostar IRAS 16293–2422 Source B at a sub-arcsecond resolution with ALMA. A clear chemical differentiation is seen in their distributions; OCS and H2CS are extended with a slight rotation signature, while CH3OH and HCOOCH3 are concentrated near the protostar. Such a chemical change in the vicinity of the protostar is similar to the companion (Source A) case. The extended component is interpreted by the infalling-rotating envelope model with a nearly face-on configuration. The radius of the centrifugal barrier of the infalling-rotating envelope is roughly evaluated to be (30–50) au. The observed lines show the inverse P-Cygni profile, indicating the infall motion within a few 10 au from the protostar. The nearly pole-on geometry of the outflow lobes is inferred from the SiO distribution, and thus, the infalling and outflowing motions should coexist along the line of sight to the protostar. This implies that the infalling gas is localized near the protostar and the current launching points of the outflow have an offset from the protostar. A possible mechanism for this configuration is discussed.
Cracking the Conundrum of F-supergiant Coronae
Authors: Ayres Thomas R.
Published: February 2018

Chandra X-ray and HST far-ultraviolet (FUV) observations of three early-F supergiants have shed new light on a previous puzzle involving a prominent member of the class: α Persei (HD 20902: F5 Ib). The warm supergiant is a moderately strong, hard coronal (

K) X-ray source, but has 10 times weaker “subcoronal” Si iv 1393 Å (

K) emissions than early-G supergiants of similar high-energy properties. The α Per X-ray excess was speculatively ascribed to a close-in hyperactive G-dwarf companion, which could have escaped previous notice, lost in the glare of the bright star. However, a subsequent dedicated multi-wavelength imaging campaign failed to find any evidence for a resolved secondary. The origin of the α Per high-energy dichotomy then devolved to (1) an unresolved companion or (2) intrinsic coronal behavior. Exploring the second possibility, the present program has found that early-F supergiants do appear to belong to a distinct coronal class, characterized by elevated X-ray/FUV ratios, although sharing some similarities with Cepheid variables in their transitory X-ray “high states.” Remarkably, the early-F supergiants now are seen to align with the low-activity end of the X-ray/FUV sequence defined by late-type dwarfs, suggesting that the disjoint behavior relative to the G supergiants might be attributed to thinner outer atmospheres on the F types, as in dwarfs, but in this case perhaps caused by a weakened “ionization valve” effect due to overly warm photospheres.
HelMod in the Works: From Direct Observations to the Local Interstellar Spectrum of Cosmic-Ray Electrons
Authors: Boschini M. J. , Torre S. Della , Gervasi M. , Grandi D. , Jóhannesson G. , La Vacca G. , Masi N. , Moskalenko I. V. , Pensotti S. , Porter T. A. , Quadrani L. , Rancoita P. G. , Rozza D. , Tacconi M.
Published: February 2018

The local interstellar spectrum (LIS) of cosmic-ray (CR) electrons for the energy range 1 MeV to 1 TeV is derived using the most recent experimental results combined with the state-of-the-art models for CR propagation in the Galaxy and in the heliosphere. Two propagation packages, GALPROP and HelMod, are combined to provide a single framework that is run to reproduce direct measurements of CR species at different modulation levels, and at both polarities of the solar magnetic field. An iterative maximum-likelihood method is developed that uses GALPROP-predicted LIS as input to HelMod, which provides the modulated spectra for specific time periods of the selected experiments for model-data comparison. The optimized HelMod parameters are then used to adjust GALPROP parameters to predict a refined LIS with the procedure repeated subject to a convergence criterion. The parameter optimization uses an extensive data set of proton spectra from 1997 to 2015. The proposed CR electron LIS accommodates both the low-energy interstellar spectra measured by Voyager 1 as well as the high-energy observations by PAMELA and AMS-02 that are made deep in the heliosphere; it also accounts for Ulysses counting rate features measured out of the ecliptic plane. The interstellar and heliospheric propagation parameters derived in this study agree well with our earlier results for CR protons, helium nuclei, and anti-protons propagation and LIS obtained in the same framework.
The Effects of Ram Pressure on the Cold Clouds in the Centers of Galaxy Clusters
Authors: Li Yuan , Ruszkowski Mateusz , Tremblay Grant
Published: February 2018

We discuss the effect of ram pressure on the cold clouds in the centers of cool-core galaxy clusters, and in particular, how it reduces cloud velocity and sometimes causes an offset between the cold gas and young stars. The velocities of the molecular gas in both observations and our simulations fall in the range of 100–400 km s−1, which is much lower than expected if they fall from a few tens of kiloparsecs ballistically. If the intracluster medium (ICM) is at rest, the ram pressure of the ICM only slightly reduces the velocity of the clouds. When we assume that the clouds are actually “fluffier” because they are co-moving with a warm-hot layer, the velocity becomes smaller. If we also consider the active galactic nucleus wind in the cluster center by adding a wind profile measured from the simulation, the clouds are further slowed down at small radii, and the resulting velocities are in general agreement with the observations and simulations. Because ram pressure only affects gas but not stars, it can cause a separation between a filament and young stars that formed in the filament as they move through the ICM together. This separation has been observed in Perseus and also exists in our simulations. We show that the star-filament offset, combined with line-of-sight velocity measurements, can help determine the true motion of the cold gas, and thus distinguish between inflows and outflows.
Frequently Occurring Reconnection Jets from Sunspot Light Bridges
Authors: Tian Hui , Yurchyshyn Vasyl , Peter Hardi , Solanki Sami K. , Young Peter R. , Ni Lei , Cao Wenda , Ji Kaifan , Zhu Yingjie , Zhang Jingwen , Samanta Tanmoy , Song Yongliang , He Jiansen , Wang Linghua , Chen Yajie
Published: February 2018

Solid evidence of magnetic reconnection is rarely reported within sunspots, the darkest regions with the strongest magnetic fields and lowest temperatures in the solar atmosphere. Using the world’s largest solar telescope, the 1.6 m Goode Solar Telescope, we detect prevalent reconnection through frequently occurring fine-scale jets in the Hα line wings at light bridges, the bright lanes that may divide the dark sunspot core into multiple parts. Many jets have an inverted Y-shape, shown by models to be typical of reconnection in a unipolar field environment. Simultaneous spectral imaging data from the Interface Region Imaging Spectrograph show that the reconnection drives bidirectional flows up to 200 km s−1, and that the weakly ionized plasma is heated by at least an order of magnitude up to ∼80,000 K. Such highly dynamic reconnection jets and efficient heating should be properly accounted for in future modeling efforts of sunspots. Our observations also reveal that the surge-like activity previously reported above light bridges in some chromospheric passbands such as the Hα core has two components: the ever-present short surges likely to be related to the upward leakage of magnetoacoustic waves from the photosphere, and the occasionally occurring long and fast surges that are obviously caused by the intermittent reconnection jets.
Dust Coagulation Regulated by Turbulent Clustering in Protoplanetary Disks
Authors: Ishihara Takashi , Kobayashi Naoki , Enohata Kei , Umemura Masayuki , Shiraishi Kenji
Published: February 2018

The coagulation of dust particles is a key process in planetesimal formation. However, the radial drift and bouncing barriers are not completely resolved, especially for silicate dust. Since the collision velocities of dust particles are regulated by turbulence in a protoplanetary disk, turbulent clustering should be properly treated. To that end, direct numerical simulations (DNSs) of the Navier–Stokes equations are requisite. In a series of papers, Pan & Padoan used a DNS with Reynolds number Re ∼ 1000. Here, we perform DNSs with up to Re = 16,100, which allow us to track the motion of particles with Stokes numbers of 0.01 ≲ St ≲ 0.2 in the inertial range. Through the DNSs, we confirm that the rms relative velocity of particle pairs is smaller by more than a factor of two, compared to that by Ormel & Cuzzi. The distributions of the radial relative velocities are highly non-Gaussian. The results are almost consistent with those by Pan & Padoan or Pan et al. at low Re. Also, we find that the sticking rates for equal-sized particles are much higher than those for different-sized particles. Even in the strong-turbulence case with α-viscosity of 10−2, the sticking rates are as high as ≳50% and the bouncing probabilities are as low as ∼10% for equal-sized particles of St ≲ 0.01. Thus, turbulent clustering plays a significant role in the growth of centimeter-sized compact aggregates (pebbles) and also enhances the solid abundance, which may lead to the streaming instability in a disk.
A Color-locus Method for Mapping RV Using Ensembles of Stars
Authors: Lee Albert , Green Gregory M. , Schlafly Edward F. , Finkbeiner Douglas P. , Burgett William , Chambers Ken , Flewelling Heather , Hodapp Klaus , Kaiser Nick , Kudritzki Rolf-Peter , Magnier Eugene , Metcalfe Nigel , Wainscoat Richard , Waters Christopher
Published: February 2018

We present a simple but effective technique for measuring angular variation in R

V
across the sky. We divide stars from the Pan-STARRS1 catalog into Healpix pixels and determine the posterior distribution of reddening and R

V
for each pixel using two independent Monte Carlo methods. We find the two methods to be self-consistent in the limits where they are expected to perform similarly. We also find some agreement with high-precision photometric studies of R

V
in Perseus and Ophiuchus, as well as with a map of reddening near the Galactic plane based on stellar spectra from APOGEE. While current studies of R

V
are mostly limited to isolated clouds, we have developed a systematic method for comparing R

V
values for the majority of observable dust. This is a proof of concept for a more rigorous Galactic reddening map.
The Effect of Combined Magnetic Geometries on Thermally Driven Winds. II. Dipolar, Quadrupolar, and Octupolar Topologies
Authors: Finley Adam J. , Matt Sean P.
Published: February 2018

During the lifetime of Sun-like or low-mass stars a significant amount of angular momentum is removed through magnetized stellar winds. This process is often assumed to be governed by the dipolar component of the magnetic field. However, observed magnetic fields can host strong quadrupolar and/or octupolar components, which may influence the resulting spin-down torque on the star. In Paper I, we used the MHD code PLUTO to compute steady-state solutions for stellar winds containing a mixture of dipole and quadrupole geometries. We showed the combined winds to be more complex than a simple sum of winds with these individual components. This work follows the same method as Paper I, including the octupole geometry, which not only increases the field complexity but also, more fundamentally, looks for the first time at combining the same symmetry family of fields, with the field polarity of the dipole and octupole geometries reversing over the equator (unlike the symmetric quadrupole). We show, as in Paper I, that the lowest-order component typically dominates the spin-down torque. Specifically, the dipole component is the most significant in governing the spin-down torque for mixed geometries and under most conditions for real stars. We present a general torque formulation that includes the effects of complex, mixed fields, which predicts the torque for all the simulations to within 20% precision, and the majority to within ≈5%. This can be used as an input for rotational evolution calculations in cases where the individual magnetic components are known.
On the Observability of Individual Population III Stars and Their Stellar-mass Black Hole Accretion Disks through Cluster Caustic Transits
Authors: Windhorst Rogier A. , Timmes F. X. , Wyithe J. Stuart B. , Alpaslan Mehmet , Andrews Stephen K. , Coe Daniel , Diego Jose M. , Dijkstra Mark , Driver Simon P. , Kelly Patrick L. , Kim Duho
Published: February 2018

We summarize panchromatic Extragalactic Background Light data to place upper limits on the integrated near-infrared surface brightness (SB) that may come from Population III stars and possible accretion disks around their stellar-mass black holes (BHs) in the epoch of First Light, broadly taken from z ≃ 7–17. Theoretical predictions and recent near-infrared power spectra provide tighter constraints on their sky signal. We outline the physical properties of zero-metallicity Population III stars from MESA stellar evolution models through helium depletion and of BH accretion disks at

. We assume that second-generation non-zero-metallicity stars can form at higher multiplicity, so that BH accretion disks may be fed by Roche-lobe overflow from lower-mass companions. We use these near-infrared SB constraints to calculate the number of caustic transits behind lensing clusters that the James Webb Space Telescope and the next-generation ground-based telescopes may observe for both Population III stars and their BH accretion disks. Typical caustic magnifications can be

, with rise times of hours and decline times of

year for cluster transverse velocities of

km s−1. Microlensing by intracluster-medium objects can modify transit magnifications but lengthen visibility times. Depending on BH masses, accretion-disk radii, and feeding efficiencies, stellar-mass BH accretion-disk caustic transits could outnumber those from Population III stars. To observe Population III caustic transits directly may require monitoring 3–30 lensing clusters to

mag over a decade.
Comparative Clinical Efficacy between Electrodesiccation with Curettage and Application of 80% Phenol Solution in Treatment of Common Warts
Authors: Dalimunthe Dina Arwina , Siregar Remenda , Tanjung Chairiyah
Published: February 2018

BACKGROUND: Common warts are skin diseases caused by human papillomavirus. Several treatment modalities available for common warts, two of them are electrodesiccation with curettage and application of 80% phenol solution.AIM: This study aims to compare clinical efficacy between these two modalities.MATERIAL AND METHODS: the Open clinical trial was conducted at Dr.Pirngadi General Hospital Medan and H.Adam Malik General Hospital Medan from February to June 2013 on 17 patients with multiple common warts. Both treatments began and applied simultaneously on the same day on each patient.RESULTS: Cure rate was higher in electrodesiccation with curettage (76.5%, 100%) compared to the application of 80% phenol solution (11.8%, 64.7%) on three weeks and six weeks of follow up. Statistical analysis showed a significant difference of common warts cure rate between electrodesiccation with curettage and application of 80% phenol solution after three weeks (p < 0.001) and six weeks (p = 0.018) of treatment.CONCLUSION: As a conclusion, electrodesiccation with curettage has higher cure rate than the application of 80% phenol solution on the treatment of common warts. Further study is needed to find out the best concentration and time interval for application of phenol solution to improve its clinical efficacy as an alternative treatment of choice for common warts.
Effect of a Histone Deacetylases Inhibitor of IL-18 and TNF-Alpha Secretion in Vitro
Authors: Dobreva Zlatka Georgieva , Grigorov Boncho Grigorov , Stanilova Spaska Angelova
Published: February 2018

BACKGROUND: Interleukin-18 (IL-18) and Tumor Necrosis Factor-alpha (TNF-α) are proinflammatory cytokines that increased the development of Th1 immune response, but have a different type of regulation of the gene expression. Whereas TNF-α has an inducible expression, IL-18 is translated as an inactive protein and required proteolytic cleavage by Casp-1 in inflammasome complexes.AIM: To investigate the effect of the histone deacetylases inhibitor Suberoylanilide Hydroxamic Acid (SAHA) on the gene expression and secretion of both cytokines, IL-18 and TNF-α, according to their contribution to the cancer development and anticancer immunity.METHODS: Isolated peripheral blood mononuclear cells (PBMC) were stimulated with LPS and C3bgp with or without SAHA. Cytokine production was assessed by ELISA at 6 and 24h.RESULTS: IL-18 and TNF-α secretion was significantly increased at 6h and 24h in response to stimulation. TNF-α production from stimulated PBMC was downregulated by SAHA at 6 and 24h. Treatment with SAHA does not inhibit the secretion of IL-18 significantly either at 6 or 24h of stimulation.CONCLUSION: The inhibition of histone deacetylases by SAHA does not influence the inflammasome-dependent production of immunologically active IL-18. In contrast, the production of proinflammatory TNF-α in cultures was mediated by the activity of HDAC class I and class II enzymes.
Angulated Dental Implants in Posterior Maxilla FEA and Experimental Verification
Authors: Hamed Hamed A. , Marzook Hamdy A. , Ghoneem Nahed E. , El–Anwar Mohamed I.
Published: February 2018

AIM: This study aimed to evaluate the effect of different implant angulations in posterior maxilla on stress distribution by finite element analysis and verify its results experimentally.METHODS: Two simplified models were prepared for an implant placed vertically and tilted 25° piercing the maxillary sinus. Geometric models' components were prepared by Autodesk Inventor then assembled in ANSYS for finite element analysis. The results of finite element analysis were verified against experimental trials results which were statistically analysed using student t-test (level of significance p < 0.05).RESULTS: Implant - abutment complex absorbed the load energy in case of vertical implant better than the case of angulated one. That was reflected on cortical bone stress, while both cases showed stress levels within the physiological limits. Comparing results between FEA and experiment trials showed full agreement.CONCLUSION: It was found that the tilted implant by 25° can be utilised in the posterior region maxilla for replacing maxillary first molar avoiding sinus penetration. The implant-bone interface and peri-implant bones received the highest Von Mises stress. Implant - bone interface with angulated implant received about 66% more stresses than the straight one.
Trump’s “America First” Foreign Policy: The Resurgence of the Jacksonian Tradition?
Authors: Dimitrova Anna
Published: February 2018

Trois questions principales semblent être au cœur des débats académiques actuels concernant la stratégie de politique étrangère du Président américain Donald Trump : 1) Y a-t-il une « doctrine Trump » ou une « grande stratégie » en matière de politique étrangère ? ; 2) La politique étrangère de Trump s’inscrit-elle dans une tradition historique de la politique étrangère américaine ? ; 3) Quels sont les risques liés à la politique extérieure de Trump ? En nous appuyant sur le modèle conceptuel de « grande stratégie » de Posen et Ross, nous émettons, en premier lieu, l’hypothèse que Trump a, en effet, défini une « grande stratégie » qui est basée sur une vision clairement nationaliste du rôle des États-Unis dans les affaires globales, étroitement centrée sur les intérêts américains et les gains matériaux, et qui prône l’application d’une approche pragmatique, appelée « America First », destinée à faire face aux principales menaces pour les intérêts nationaux américains, que sont l’Islam radical et le terrorisme, les accords commerciaux et les alliances internationales jugés « injustes » pour l’Amérique, et l’immigration illégale. En second lieu, dans la lignée de la théorie de Mead, nous cherchons à démontrer que la grande stratégie de Trump trouve ses origines dans l’histoire de la politique étrangère américaine et reflète, d’une certaine manière, le retour de la tradition de la politique étrangère du XIX e siècle décrite par Mead comme le Jacksonianisme en lien avec la présidence d’Andrew Jackson. En conclusion, nous examinons brièvement les risques liés au retour d’une Amérique Jacksonienne.
Dire/Donner. Note sur les verbes trivalents
Authors: Descombes Vincent
Published: February 2018

Charles Sanders Peirce a montré qu’il y a des relations triadiques, comme telles irréductibles à des conjonctions de relations dyadiques. Il a pris pour exemple les relations instaurées par un acte du don entre le donateur, la chose donnée et le donataire. De son côté, Lucien Tesnière a étudié la syntaxe des verbes trivalents, dont il a donné deux grands exemples : les verbes de dire et les verbes de don. Quel rapport entre la logique du triadique et la syntaxe de la trivalence ? Tous les verbes dont la syntaxe requiert trois compléments ne sont pas triadiques car la logique de l’objet de dire est celle d’un objet propositionnel (dire, c’est dire que…) alors que la logique de la chose donnée est celle d’un objet identifiable (donner un livre, c’est donner ce livre-ci ou celui-là).
Au risque de soi : parler, donner, attester
Authors: Hénaff Marcel
Published: February 2018

Une approche du rapport entre don et langage exige d’abord une clarification sur l’usage même du verbe donner, verbe multifonctionnel dont les ressources peuvent égarer. Ainsi, « donner sa parole » n’est en rien faire un cadeau, c’est attester de soi par un acte de langage. Mais le choix du verbe  donner  n’est pas quelconque. Donner indique toujours un mouvement vers autrui, une sortie de soi, un rapport à un autre réel hors de moi, le « tu » corrélat du « je » qui parle et qui s’engage en parlant. Pacte implicite qui est celui du don cérémoniel, avec sa dimension de risque et de confiance dont l’alliance exogamique est l’exemple abouti et dont on retrouve le schème dans le serment et la promesse. Ce qui est en jeu est le Soi comme sujet responsable et un sentiment de l’honneur inséparable de son ipséité même.
Donner des mots et des choses. De Mauss à Hobbes (et retour)
Authors: Boyer Alain
Published: February 2018

Dans ce chapitre XV ( Chose promise. Étude sur la promesse à partir de Hobbes et quelques autres , PUF, 2014), l’hypothèse selon laquelle la promesse et ses avatars sont au cœur du lien social est confrontée, trop rapidement, aux analyses classiques du grand Essai sur le don de Mauss. Le don maussien n’est pas un don « gratuit », ni un commerce marchand, c’est un système complexe d’obligations sociales. On essaie de montrer que les riches et profondes analyses de Mauss, y compris sur le potlatch , ne s’opposent pas tant que cela à certains éléments de la pensée de Hobbes telle que nous l’avons interprétée. Il s’agit selon Mauss, plus généralement, de « substituer l’alliance, le don et le commerce à la guerre, l’isolement et la stagnation », trois termes qui ne peuvent pas ne pas évoquer la phrase la plus célèbre du Léviathan (« and the life of man is solitary, poor, nasty, brutish and short »), décrivant l’état de nature. C’est dans ce monde de petites sociétés sans État que l’échange non marchand décrit par Mauss sous le titre de « don/contre-don » peut avoir lieu, pour créer des solidarités, sans que la valeur de la « vaine gloire » mise en évidence par Hobbes en soit du tout absente. Une moindre vexation, et c’est à nouveau la guerre. Quoi qu’il en soit, le don maussien peut être interprété comme une espèce du genre « pacte ».
L’enfant sans « merci ». Pour une clinique du donner-recevoir-rendre
Authors: Michard Pierre
Published: February 2018

L’article se propose de se pencher sur un courant de thérapie familiale : l’approche contextuelle. Böszörményi-Nagy, son créateur, invente un dispositif d’entretiens qui interpelle des partenaires familiaux sur leurs relations en termes de donner, recevoir et rendre. Le thérapeute ne cède rien sur cette option à l’aide du levier d’un questionnement qui donne à penser et à dire sur le « compte relationnel » de chacun avec le proche. Böszörményi-Nagy insiste sur l’oubli de l’enfant capable de don, la thérapie prend parti d’aider les parents à dire les mots qui créditent les contributions clandestines de l’enfant. Cette proposition thérapeutique de mettre en mots les déficits de réciprocité ou de reconnaissance est particulièrement pertinente lorsque le cycle du don est bloqué et se manifeste par des symptômes au cœur de la relation.
Le quasi-contrat, un concept anthropologique ?
Authors: Bucaille Richard , Virieux Jeanne
Published: February 2018

Pour nommer cette « force » étrange, incluse « dans la chose qu’on donne » et qui « fait que le présent reçu est obligatoirement rendu », Mauss propose la notion maorie de  hau.  Essayant de mieux nommer ce principe de tout échange sociétal (y compris celui, si délicat, avec la divinité), on propose et tente de justifier le terme, emprunté au droit et peut-être plus large et à la fois plus précis, de « quasi-contrat », implicite mais presque irrésiliable, dont on avance plusieurs exemples variés. On insiste sur l’importance de ces quasi-contrats dans toutes les situations de conflit – guerre au premier chef – où le droit se trouve outrepassé par la violence. Enfin, il faut noter la proximité de ce quasi-contrat avec la notion centrale de l’économie des conventions.
Angoisses académiques
Authors: Berliner David
Published: February 2018

Parce qu’elle déstabilise le réel, l’anthropologie est une discipline anxiogène. Dans cet article, j’explore certaines de ces angoisses que le capitalisme académique qui prévaut aujourd’hui a contribué à amplifier.
Les ruses de l'opium
Authors: Vergne François
Published: February 2018

Le lecteur qui aborde les oeuvres des écrivains opiomanes ne peut éluder la question du statut de la drogue par rapport au texte qui en dit les effets et en transcrit les visions. L'opium est-il la condition première d'une création littéraire dont il finirait, en ultime lecture, par entraver le développement ? Ou bien contraint-il l'écrivain à trouver un équilibre, nécessairement périlleux, entre onirisme et réflexion théorique ? Cet article cherche à montrer de quelle manière – à travers les exemples de Coleridge, De Quincey et Collins – l'élaboraticn d'un système esthétique s'appuie sur la thématique que fournit l'opium, tout en le reléguant, in fine, au rôle de métaphore d'une quête dont il souligne l'altérité.
La ligne prend corps
Authors: Yampolsky Mikhaïl
Published: February 2018

La mescaline, de même que d'autres drogues, change la voie de la perception visuelle en déplaçant la « lecture » de la figure vers le fond et en rendant les graphes linéaires. Ces modifications bouleversent la construction de l'illusion de réalité. L'auteur étudie ces métamorphoses de la perception visuelle, stimulées par les modificateurs de conscience, telles qu'elles apparaissent dans quelques textes classiques du XIXème siècle : les histoires policières d'Edgar Poe et de Conan Doyle, le « rêve de l'injection d'Irma », de Sigmund Freud.
Le pinceau ivre
Authors: Fraysse Pierre
Published: February 2018

A partir de son expérience de thérapeute en atelier d'expression picturale, destiné préférentiellement aux malades alcooliques, l'auteur s'interroge sur les correspondances éventuelles entre les oeuvres de peintres connus pour leur intempérance. Au-delà de toute considération esthétique ou normative, et sans a priori pathographique, l'auteur dégage des traits communs, établissant un lien entre la sémiologie des pathologies addictives et les techniques picturales. Il insiste en particulier sur le « court-circuitage » émotionnel, véritable pont affectif entre l'artiste et le spectateur.
Le Silence des théâtres sur la drogue et l'alcool : autocensure ou censure ?
Authors: Krakovitch Odile
Published: February 2018

Une seule pièce sur l'opium. Quelques drames sur des jeunes gens noyant leur ennui dans l'alcool. Deux ou trois mélodrames dénonçant le refuge au cabaret de l'ouvrier accablé de misère. Et c'est tout jusqu'en 1879, date de la représentation de L'Assommoir. Pourquoi un tel silence ? A cause de l'auto-censure que s'infligèrent les auteurs de 1830 à 1850 dans leur souci de présenter au peuple une image de lui même valorisante et pédagogique ; puis à cause de la censure que s'imposa le Second Empire, dès avant le coup d'Etat, sur tous les thèmes sociaux et socialisants. Le théâtre au XIXème siècle eut un rôle pédagogique que personne ne nia jamais, ni les auteurs, ni les gouvernements et les publics, ni les critiques et les censeurs. Impossible donc, de 1830 à 1850, de présenter un ouvrier ivre. Au contraire, et c'est la seconde raison de l'auto-censure des dramaturges, avec l'essor du mélodrame social s'instaure l'habitude d'opposer l'ouvrier honnête, travailleur, au patron noble et ignoble, dilapidant l'outil de travail : usine ou propriété agricole. Le vice ne provient que de deux causes : l'amour des femmes ou l'âpreté au gain, l'argent trop facilement gagné. Sous le Second Empire, la censure remplaça l'auto-censure. Sensible à l'influence qu'eut le mélodrame sur l'éclosion du socialisme et de la Révolution de 1848, Napoléon III refusa toute représentation de lutte de classes, de conflits sociaux. La dépravation se situe dans la bourgeoisie, a pour cadre la Bourse et les salons. La prostitution est le thème au delà duquel on ne peut pas représenter la misère, sinon la censure intervient. C'est pourquoi L'Assommoir, présenté à L'Ambigu comique en 1879, fit scandale et bouleversa l'opinion, encore plus que le roman paru deux ans auparavant, en ce siècle infiniment plus sensible à la parole, au spectacle, qu'à la lecture.
Generative processing of animated partial depictions fosters fish identification skills: eye tracking evidence
Authors: Boucheix Jean-Michel , Lowe Richard K.
Published: February 2018

Cette étude s’intéresse à l’apprentissage de la reconaissance des espèces de poissons à partir de leur locomotion, activité pouvant être réalisée par des professionnels dans le cadre de la protection des espèces et de la biodiversité : comment ces patterns dynamiques fonctionnent-ils et comment favoriser leur apprentissage ? La présente expérimentation a été réalisée dans le cadre d’un projet international plus vaste : le projet “Fish Locomotion” visant à concevoir et tester des outils multimédias pour la formation à la reconnaissance des espèces. Cette recherche s’intéresse particulièrement à la formation des compétences des professionnels dans des tâches de surveillance des espèces de poissons des mers et océans, lors d’enquêtes sur la bio-diversité. Ils doivent identifier les espèces de poissons à partir des vidéos enregistrées dans les océans, les mers (ou les lacs). Traditionnellement, la reconnaissance des espèces de poissons est effectuée en utilisant la classification biologique conventionnelle qui est basée sur les caractéristiques des formes corporelles. Cependant, très souvent, lorsque les conditions d’observation deviennent difficiles (turbidité de l’eau par exemple), la reconnaissance conventionnelle basée sur la forme semble ne plus être efficace. Une autre classification, basée sur les types de locomotion, donc fondée sur des traits plus dynamiques, a été développée par des biologistes. Dans la présente étude, le but est d’explorer le bénéfice potentiel d’une méthode d’apprentissage fondée sur l’effet de génération d’animation interne. Dans le cadre théorique de l’imagerie cognitive, et des systèmes de neurones miroirs en neuroscience, la présente expérience a étudié l’effet de l’imagination par rapport à la visualisation des animations de la locomotion des poissons. Des novices (étudiants) ont appris la locomotion de poissons, à partir d’animation 3D. Au cours d’une tâche d’apprentissage perceptif, nous avons comparé 4 conditions de présentation de l’animation du poisson : selon le groupe, les apprenants pouvaient voir soit uniquement la tête du poisson, seulement le milieu du corps, la queue seule ou le poisson entier, condition de contrôle. Le movement des yeux de chaque participant a été enregistré durant l’apprentissage afin d’évaluer l’hypothése de la mise en oeuvre d’une animation interne du mouvement du poisson de type simulation mentale. Le post-test était une tâche de reconnaissance de la locomotion du poisson (par rapport à d’autres mouvements de poissons différents, comme une anguille par exemple). Les résultats ont indiqué que l’apprentissage à partir de movements de locomotion incomplets (comme la tête seule) de poisson conduisait à des gains plus élevés que l’apprentissage à partir du mouvement complet (condition contrôle). L’implication des résultats pour la conception pédagogique de la formation est discutée.
Migraine Variants in Children
Authors: Rothner A. David
Published: February 2018

Migraine in children can manifest in ways that are markedly different from adult migraines. In children, migraine variants are often unaccompanied by headache and include conditions such as cyclic vomiting and abdominal migraine. Children who experience these conditions are often thought to have a disorder of the gastrointestinal tract, and when evaluation is unremarkable they may be diagnosed as having a conversion reaction. Complicated migraines, on the other hand, are often accompanied by focal neurological symptoms such as ataxia, hemiparesis, or altered level of consciousness that evoke great consternation in the examining clinician. Certain episodic syndromes that may hold interest to pediatricians are also discussed in this article, mostly to emphasize the ambiguity that still surrounds these disorders, such as migraine triggered by trauma. The cardinal rule that most of these disorders are diagnoses of exclusion and can only be confirmed after extensive evaluation, either by the pediatrician or pediatric neurologist, is emphasized.

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Pediatr Ann.
2018;47(2):e50–e54.]
Management of Pediatric Migraine: Current Therapies
Authors: Khrizman Marina , Pakalnis Ann
Published: February 2018

Migraine is one of the most common neurologic conditions in pediatrics. It can be a significant stressor, causing absences from school and interruption of parents' work and family schedules. The mainstay of treatment remains educating patients about healthy lifestyle practices and the influences of sleep, stressors, and hydration on triggering migraine attacks. Psychological therapies such as biofeedback or cognitive-behavioral therapy may be beneficial in some patients, especially those with prominent psychological comorbidities. New advances in the pathophysiology of migraine and additional pediatric approval of abortive therapy with triptans have led to significant advances in the management of migraine in children. Some challenges to preventive therapy were recently noted with the negative results obtained in the Childhood and Adolescent Migraine Prevention Study, which compared prescription drugs to placebo. Inherent differences between adult and pediatric headaches, with shorter duration of pediatric migraine and prominent placebo effect, present recurring challenges for clinicians.

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Pediatr Ann.
2018;47(2):e55–e60.]