bluuebunny/crossref_metadata_2025_split huggingface dataset:
ECLIPSE RECORDS IN A CORPUS OF COLONIAL ZAPOTEC 260-DAY CALENDARS
Authors: Tavárez David , Justeson John 
Published: May 2008

AbstractThis paper translates and analyzes references to eclipses in two seventeenth-century Zapotec calendrical booklets.1These booklets are part of a corpus of 106 separate calendrical texts and four collections of ritual songs that were turned over to ecclesiastical authorities in 1704 and 1705 as part of an ambitious campaign against traditional indigenous ritual practices conducted in the province of Villa Alta in northern Oaxaca. Both of these booklets contain a complete day-by-day representation of the Zapotec 260-day divinatory calendar, with annotations in Zapotec alongside many of these entries. Two such annotations in Booklet 81 explicitly record the occurrences of solar and lunar eclipses visible in the Sierra Zapoteca in 1691 and 1693. Annotations in Booklet 63 do not mention eclipses but allude to them by recording the names and Gregorian dates of Christian feasts celebrated on the dates of eclipses in 1686 and 1690; such allusions are otherwise found mainly with the Zapotec dates of the beginnings or ends of significant Zapotec calendrical cycles—the 260-day calendar itself or its 65-day subdivisions, and the start of the Zapotec 365-day year—and so reflect a systematic pattern of engagement by at least one Zapotec calendar specialist with indigenous ritual knowledge and practices. Our analysis suggests that colonial Zapotec calendar specialists monitored and perhaps also anticipated the occurrence of eclipses in terms of the patterns of eclipse recurrence in particular parts of the divinatory calendar.
Molecular mechanisms of antibody-mediated neutralisation of flavivirus infection
Authors: Pierson Theodore C. , Diamond Michael S. 
Published: May 2008

AbstractFlaviviruses are a group of positive-stranded RNA viruses that cause a spectrum of severe illnesses globally in more than 50 million individuals each year. While effective vaccines exist for three members of this group (yellow fever, Japanese encephalitis, and tick-borne encephalitis viruses), safe and effective vaccines for several other flaviviruses of clinical importance, including West Nile and dengue viruses, remain in development. An effective humoral immune response is critical for protection against flaviviruses and an essential goal of vaccine development. The effectiveness of virus-specific antibodies in vivo reflects their capacity to inhibit virus entry and spread through several mechanisms, including the direct neutralisation of virus infection. Recent advances in our understanding of the structural biology of flaviviruses, coupled with the use of small-animal models of flavivirus infection, have promoted significant advances in our appreciation of the factors that govern antibody recognition and inhibition of flaviviruses in vitro and in vivo. In this review, we discuss the properties that define the potency of neutralising antibodies and the molecular mechanisms by which they inhibit virus infection. How recent advances in this area have the potential to improve the development of safe and effective vaccines and immunotherapeutics is also addressed.
ARTEMiS (Automated Robotic Terrestrial Exoplanet Microlensing Search) – Hunting for planets of Earth mass and below
Authors: Dominik Martin , Horne Keith , Allan Alasdair , Rattenbury Nicholas J. , Tsapras Yiannis , Snodgrass Colin , Bode Michael F. , Burgdorf Martin J. , Fraser Stephen N. , Kerins Eamonn , Mottram Christopher J. , Steele Iain A. , Street Rachel A. , Wheatley Peter J. , Wyrzykowski Łukasz 
Published: May 2008

AbstractGravitational microlensing observations will lead to a census of planets that orbit stars of different populations. From 2008, ARTEMiS will provide an expert system that allows to adopt a three-step strategy of survey, follow-up and anomaly monitoring of gravitational microlensing events that is capable of detecting planets of Earth mass and below. The SIGNALMEN anomaly detector, an integral part, has already demonstrated its performance during a pilot season. Embedded into eSTAR, ARTEMiS serves as an open platform that links with existing microlensing campaigns. Real-time visualization of ongoing events along with an interpretation moreover allows to communicate “Science live to your home” to the general public.
Finding new sub-stellar co-moving companion candidates - the case of CT Cha
Authors: Schmidt Tobias , Neuhäuser Ralph 
Published: May 2008

AbstractWe have searched for close and faint companions around T Tauri stars in the Chamaeleon star forming region. Two epochs of direct imaging data were taken with the VLT Adaptive Optics instrument NaCo in February 2006 and March 2007 in Ks band for the classical T Tauri star CT Cha together with a Hipparcos binary for astrometric calibration. Moreover a J band image was taken in March 2007 to get color information. We found CT Cha to have a very faint companion (Ks0=14.6 mag) of ∼2.67” separation corresponding to ∼440AU. We show that CT Cha A and the faint object form a common proper motion pair and that the companion is not a non-moving background object (with 4σ significance).
First observation of planet-induced X-ray emission: The system HD 179949
Authors: Saar S. H. , Cuntz M. , Kashyap V. L. , Hall J. C. 
Published: May 2008

AbstractWe present the first observation of planet-induced stellar X-ray activity, identified for the HD 179949 system, using Chandra / ACIS-S. The HD 179949 system consists of a close-in giant planet orbiting an F9 V star. Previous ground-based observations already showed enhancements in Ca II K in phase with the planetary orbit. We find an ∼30% increase in the X-ray flux over quiescent levels coincident with the phase of the Ca II enhancements. There is also a trend for the emission to be hotter at increased fluxes, confirmed by modeling, showing the enhancement at ∼1 keV compared to ∼0.4 keV for the background star.
Internal waves driven by stellar irradiation in a non-synchronized hot Jupiter
Authors: Gu Pin-Gao , Ogilvie Gordon I. 
Published: May 2008

AbstractWe investigate the dynamical response of a non-synchronized hot Jupiter to stellar irradiation. In our current model, the stellar radiation acts like a diurnal thermal forcing from the top of a radiative layer of a hot Jupiter. If the thermal forcing period is longer than the sound speed crossing time of the planet's surface, the forcing can excite internal waves propagating into the planet's interior. When the planet spins faster than its orbital motion, these waves carry negative angular momentum and are damped by radiative loss as they propagate downwards from the upper layer of the radiative zone. As a result, the upper layer gains the angular momentum from the lower layer of the radiative zone. Simple estimates of angular momentum flux are made for all transiting planets.
Comparison of cloud models for Brown Dwarfs
Authors: Helling Ch. , Ackerman A. , Allard F. , Dehn M. , Hauschildt P. , Homeier D. , Lodders K. , Marley M. , Rietmeijer F. , Tsuji T. , Woitke P. 
Published: May 2008

AbstractA test case comparison is presented for different dust cloud model approaches applied in brown dwarfs and giant gas planets. We aim to achieve more transparency in evaluating the uncertainty inherent to theoretical modelling. We show in how far model results for characteristic dust quantities vary due to different assumptions. We also demonstrate differences in the spectral energy distributions resulting from our individual cloud modelling in 1D substellar atmosphere simulations.
Modeling of evolution of the rotational axis of “hot Jupiter” planets under tidal perturbations
Authors: Kitiashvili Irina 
Published: May 2008

AbstractIn this report, we present results of analytical and numerical calculations of evolution the axis of rotation of planets moving at very close orbits. We consider the evolution of the axis of rotation caused by tidal perturbations of a parent star and obtain estimates of the principal moment of inertia and the dynamical flattening for nine exoplanets. From analysis of evolutionary equations, we obtain the critical values of the kinetic momentum vector, $\vec L$, for different values of orbital eccentricity. We find a general tendency of vector $\vec L$ to evolve to the direction perpendicular to the orbital plane.
The formation of close-in planets by the slingshot model
Authors: Nagasawa Makiko , Ida Shigeru , Bessho Taisuke 
Published: May 2008

AbstractWe investigated the efficiency of planet scatterings in producing close-in planets by a direct inclusion of the dynamical tide effect into the simulations. We considered a system consists of three Jovian planets. Through a planet-planet scattering, one of the planets is sent into shorter orbit. If the eccentricity of the scattered planet is enough high, the tidal dissipation from the star makes the planetary orbit circular. We found that the short-period planets are formed at about 30% cases in our simulation and that Kozai mechanism plays an important role. In the Kozai mechanism, the high inclination obtained by planet-planet scattering is transformed to the eccentricity. It leads the pericenter of the innermost planet to approach the star close enough for tidal circularization. The formed close-in planets by this process have a widely spread inclination distribution. The degree of contribution of the process for the formation of close-in planets will be revealed by more observations of Rossiter-McLaughlin effects for transiting planets.
Formation of terrestrial planets from planetesimals around M dwarfs
Authors: Ogihara Masahiro , Ida Shigeru 
Published: May 2008

AbstractWe have investigated accretion of terrestrial planets from planetesimals around M dwarfs through N-body simulations including the effect of tidal interaction with disk gas. Because of low luminosity of M dwarfs, habitable zones around them are located near the disk inner edge. Planetary embryos undergo type-I migration and pile up near the disk inner edge. We found that after repeated close scatterings and occasional collisions, three or four planets eventually remain in stable orbits in their mean motion resonances. Furthermore, large amount of water-rich planetesimals rapidly migrate to the terrestrial planet regions from outside of the snow line, so that formed planets in these regions have much more water contents than those around solar-type stars.
Habitable planet formation in extreme planetary systems: systems with multiple stars and/or multiple planets
Authors: Haghighipour Nader 
Published: May 2008

AbstractUnderstanding the formation and dynamical evolution of habitable planets in extrasolar planetary systems is a challenging task. In this respect, systems with multiple giant planets and/or multiple stars present special complications. The formation of habitable planets in these environments is strongly affected by the dynamics of their giant planets and/or their stellar companions. These objects have profound effects on the structure of the disk of planetesimals and protoplanetary objects in which terrestrial-class planets are formed. To what extent the current theories of planet formation can be applied to such “extreme” planetary systems depends on the dynamical characteristics of their planets and/or their binary stars. In this paper, I present the results of a study of the possibility of the existence of Earth-like objects in systems with multiple giant planets (namely υ Andromedae, 47 UMa, GJ 876, and 55 Cnc) and discuss the dynamics of the newly discovered Neptune-sized object in 55 Cnc system. I will also review habitable planet formation in binary systems and present the results of a systematic search of the parameter-space for which Earth-like objects can form and maintain long-term stable orbits in the habitable zones of binary stars.
Planetary migration in gaseous protoplanetary disks
Authors: Masset Frédéric S. 
Published: May 2008

AbstractTides come from the fact that different parts of a system do not fall in exactly the same way in a non-uniform gravity field. In the case of a protoplanetary disk perturbed by an orbiting, prograde protoplanet, the protoplanet tides raise a wake in the disk which causes the orbital elements of the planet to change over time. The most spectacular result of this process is a change in the protoplanet's semi-major axis, which can decrease by orders of magnitude on timescales shorter than the disk lifetime. This drift in the semi-major axis is called planetary migration. In a first part, we describe how the planet and disk exchange angular momentum and energy at the Lindblad and corotation resonances. Next we review the various types of planetary migration that have so far been contemplated: type I migration, which corresponds to low-mass planets (less than a few Earth masses) triggering a linear disk response; type II migration, which corresponds to massive planets (typically at least one Jupiter mass) that open up a gap in the disk; “runaway” or type III migration, which corresponds to sub-giant planets that orbit in massive disks; and stochastic or diffusive migration, which is the migration mode of low- or intermediate-mass planets embedded in turbulent disks. Lastly, we present some recent results in the field of planetary migration.
Dust evolution in protoplanetary disks
Authors: Gonzalez Jean-François , Fouchet Laure , Maddison Sarah T. , Laibe Guillaume 
Published: May 2008

AbstractWe investigate the behaviour of dust in protoplanetary disks under the action of gas drag using our 3D, two-fluid (gas+dust) SPH code. We present the evolution of the dust spatial distribution in global simulations of planetless disks as well as of disks containing an already formed planet. The resulting dust structures vary strongly with particle size and planetary gaps are much sharper than in the gas phase, making them easier to detect with ALMA than anticipated. We also find that there is a range of masses where a planet can open a gap in the dust layer whereas it doesn't in the gas disk. Our dust distributions are fed to the radiative transfer code MCFOST to compute synthetic images, in order to derive constraints on the settling and growth of dust grains in observed disks.
Type I planetary migration in a self-gravitating disk
Authors: Baruteau Clément , Masset Frédéric 
Published: May 2008

AbstractWe investigate the impact of the disk self-gravity on type I migration. We first show that considering a planet migrating in a disk without self-gravity can lead to a significant overestimate of the migration rate. Unbiased drift rates can be obtained only if the planet and the disk feel the same gravitational potential. We then confirm that the disk gravity slightly accelerates type I migration.
On type I planetary migration in adiabatic disks
Authors: Baruteau Clément , Masset Frédéric 
Published: May 2008

AbstractWe investigate type I migration in a two-dimensional adiabatic disk. We find entropy perturbations that are advected in the planet's coorbital region. These entropy perturbations yield an excess of corotation torque that scales with the unperturbed entropy gradient at corotation. This torque excess can be large enough to slow down migration significantly, or even stop it.
On the dynamics of Trojan planets in extrasolar planetary systems
Authors: Dvorak R. , Schwarz R. , Lhotka Ch. 
Published: May 2008

AbstractIn this article we examine the motion of fictitious Trojan planets close to the equilateral Lagrangean equilibrium points in extrasolar planetary systems. Whether there exist stable motion in this area or not depends on the massratio of the primariy bodies in the restricted three body problem, namely the host star and the gasgiant. Taking into account also the eccentricity of the primaries we show via results of extensive numerical integrations that Trojan planets may survive only for e < 0.25. We also show first results of a mapping in the 1:1 resonance with a gas giant on an eccentric orbit which is applied to the extrasolar planetary systems HD 17051. We furthermore study the influence of an additional outer planet which perturbs the motion of the gasgiant as well as the Trojan cloud around its L4 Lagrangean point.
Habitable zones for Earth-mass planets in multiple planetary systems
Authors: JI Jianghui , LIU Lin , KINOSHITA Hiroshi , LI Guangyu 
Published: May 2008

AbstractWe perform numerical simulations to study the Habitable zones (HZs) and dynamical structure for Earth-mass planets in multiple planetary systems. For example, in the HD 69830 system, we extensively explore the planetary configuration of three Neptune-mass companions with one massive terrestrial planet residing in 0.07 AU ≤ a ≤ 1.20 AU, to examine the asteroid structure in this system. We underline that there are stable zones of at least 105 yr for low-mass terrestrial planets locating between 0.3 and 0.5 AU, and 0.8 and 1.2 AU with final eccentricities of e < 0.20. Moreover, we also find that the accumulation or depletion of the asteroid belt are also shaped by orbital resonances of the outer planets, for example, the asteroidal gaps at 2:1 and 3:2 mean motion resonances (MMRs) with Planet C, and 5:2 and 1:2 MMRs with Planet D. In a dynamical sense, the proper candidate regions for the existence of the potential terrestrial planets or HZs are 0.35 AU < a < 0.50 AU, and 0.80 AU < a < 1.00 AU for relatively low eccentricities, which makes sense to have the possible asteroidal structure in this system.
Chronic ethanol intake modulates vascular levels of endothelin‐1 receptor and enhances the pressor response to endothelin‐1 in anaesthetized rats
Authors: Tirapelli C R , Legros E , Brochu I , Honoré J‐C , Lanchote V L , Uyemura S A , De Oliveira A M , D'Orléans‐Juste P 
Published: May 2008

Background and purpose:The contribution of endothelin‐1 (ET‐1) to vascular hyper‐reactivity associated with chronic ethanol intake, a major risk factor in several cardiovascular diseases, remains to be investigated.Experimental approach:The biphasic haemodynamic responses to ET‐1 (0.01–0.1 nmol kg−1, i.v.) or to the selective ETB agonist, IRL1620 (0.001–1.0 nmol kg−1, i.v.), with or without ETA or ETB antagonists (BQ123 (c(DTrp‐Dasp‐Pro‐Dval‐Leu)) at 1 and 2.5 mg kg−1 and BQ788 (N‐cis‐2,6‐dimethyl‐piperidinocarbonyl‐L‐γ‐methylleucyl1‐D‐1methoxycarbonyltryptophanyl‐D‐norleucine) at 0.25 mg kg−1, respectively) were tested in anaesthetized rats, after 2 weeks' chronic ethanol treatment. Hepatic parameters and ET receptor protein levels were also determined.Key results:The initial hypotensive responses to ET‐1 or IRL1620 were unaffected by chronic ethanol intake, whereas the subsequent pressor effects induced by ET‐1, but not by IRL1620, were potentiated. BQ123 at 2.5 but not 1 mg kg−1 reduced the pressor responses to ET‐1 in ethanol‐treated rats. Conversely, BQ788 (0.25 mg kg−1) potentiated ET‐1‐induced increases in mean arterial blood pressure in control as well as in ethanol‐treated rats. Interestingly, in the latter group, increases in heart rate, induced by ET‐1 at a dose of 0.025 mg kg−1 were enhanced following ETB receptor blockade. Finally, we observed higher levels of ETA receptor in the heart and mesenteric artery and a reduction of ETB receptor protein levels in the aorta and kidney from rats chronically treated with ethanol.Conclusions and implications:Increased vascular reactivity to ET‐1 and altered protein levels of ETA and ETB receptors could play a role in the pathogenesis of cardiovascular complications associated with chronic ethanol consumption.British Journal of Pharmacology (2008) 154, 971–981; doi:10.1038/bjp.2008.157; published online 12 May 2008
Increased susceptibility of annexin‐A1 null mice to nociceptive pain is indicative of a spinal antinociceptive action of annexin‐A1
Authors: Ayoub S S , Yazid S , Flower R J 
Published: May 2008

Background and purpose:Annexin‐A1 (ANXA1), a glucocorticoid‐regulated protein, mediates several of the anti‐inflammatory actions of the glucocorticoids. Previous studies demonstrated that ANXA1 is involved in pain modulation. The current study, using ANXA1 knockout mice (ANXA1−/−), is aimed at addressing the site and mechanism of the modulatory action of ANXA1 as well as possible involvement of ANXA1 in mediating the analgesic action of glucocorticoids.Experimental approach:The acetic acid‐induced writhing response was performed in ANXA1−/−and wild‐type (ANXA1+/+) mice with spinal and brain levels of prostaglandin E2(PGE2) examined in both genotypes. The effect of the ANXA1 peptomimetic Ac2‐26 as well as methylprednisolone on the writhing response and on spinal cord PGE2of ANXA1+/+and ANXA1−/−was compared. The expression of proteins involved in PGE2synthesis, cytosolic phospholipase A2(cPLA2) and cyclooxygenases (COXs), in the spinal cord of ANXA1+/+and ANXA1−/−was also compared.Key results:ANXA1−/−mice exhibited a significantly greater writhing response and increased spinal cord levels of PGE2compared with ANXA1+/+mice. Ac2‐26 produced analgesia and reduced spinal PGE2levels in ANXA1+/+and ANXA1−/−mice, whereas methylprednisolone reduced the writhing response and spinal PGE2levels in ANXA1+/+, but not in ANXA1−/−mice. The expression of cPLA2, COX‐1, COX‐2 and COX‐3 in spinal cord tissues was upregulated in ANXA1−/−compared with ANXA1+/+.Conclusions and implications:We conclude that ANXA1 protein modulates nociceptive processing at the spinal level, by reducing synthesis of PGE2by modulating cPLA2and/or COX activity. The analgesic activity of methylprednisolone is mediated by spinal ANXA1.British Journal of Pharmacology(2008)154, 1135–1142; doi:10.1038/bjp.2008.166; published online 12 May 2008
The μ‐opioid receptor agonist morphine, but not agonists at δ‐ or κ‐opioid receptors, induces peripheral antinociception mediated by cannabinoid receptors
Authors: Da Fonseca Pacheco D , Klein A , De Castro Perez A , Da Fonseca Pacheco C M , De Francischi J N , Duarte I D G 
Published: May 2008

Background and purpose:Although participation of opioids in antinociception induced by cannabinoids has been documented, there is little information regarding the participation of cannabinoids in the antinociceptive mechanisms of opioids. The aim of the present study was to determine whether endocannabinoids could be involved in peripheral antinociception induced by activation of μ‐, δ‐ and κ‐opioid receptors.Experimental approach:Nociceptive thresholds to mechanical stimulation of rat paws treated with intraplantar prostaglandin E2(PGE2, 2 μg) to induce hyperalgesia were measured 3 h after injection using an algesimetric apparatus. Opioid agonists morphine (200 μg), (+)‐4‐[(alphaR)‐alpha‐((2S,5R)‐4‐Allyl‐2,5‐dimethyl‐1‐piperazinyl)‐3‐ methoxybenzyl]‐N,N‐diethylbenzamide (SNC80) (80 μg), bremazocine (50 μg); cannabinoid receptor antagonistsN‐(piperidin‐1‐yl)‐5‐(4‐ iodophenyl)‐1‐(2,4‐dichlorophenyl)‐4‐methyl‐1H‐pyrazole‐3‐carboxamide (AM251) (20–80 μg), 6‐iodo‐2‐methyl‐1‐[2‐(4‐morpholinyl) ethyl]‐1H‐indol‐3‐yl(4‐methoxyphenyl) methanone (AM630) (12.5–100 μg); and an inhibitor of methyl arachidonyl fluorophosphonate (MAFP) (1–4 μg) were also injected in the paw.Key results:The CB1‐selective cannabinoid receptor antagonist AM251 completely reversed the peripheral antinociception induced by morphine in a dose‐dependent manner. In contrast, the CB2‐selective cannabinoid receptor antagonist AM630 elicited partial antagonism of this effect. In addition, the administration of the fatty acid amide hydrolase inhibitor, MAFP, enhanced the antinociception induced by morphine. The cannabinoid receptor antagonists AM251 and AM630 did not modify the antinociceptive effect of SNC80 or bremazocine. The antagonists alone did not cause any hyperalgesic or antinociceptive effect.Conclusions and implications:Our results provide evidence for the involvement of endocannabinoids, in the peripheral antinociception induced by the μ‐opioid receptor agonist morphine. The release of cannabinoids appears not to be involved in the peripheral antinociceptive effect induced by κ‐ and δ‐opioid receptor agonists.British Journal of Pharmacology(2008)154, 1143–1149; doi:10.1038/bjp.2008.175; published online 12 May 2008