bluuebunny/crossref_metadata_2025 huggingface dataset:
Pseudo-karst dans des roches gréso-quartzitiques de la formation Roraima (Gran Sabana, Vénézuela )
Authors: Pouyllau Michel , Seurin Maggy
Published: February 2017

Les hauts plateaux gréso-quartzitiques de la formation Roraima présentent, dans la région de La Gran Sabana, au sud-est du Vénézuéla, des caractéristiques macro et micro-géomorphologiques particulières. D'une part, cette couverture sédimentaire précambrienne comporte des reliefs spectaculaires de hauts plateaux structuraux affectés par de grands anticlinaux, synclinaux et mono-clinaux en partie démantelés par l'érosion ; d'autre part, dans le détail, des formes pseudo-karstiques se sont développées tant sur les silcrètes de surface (lapiés, guillochages, etc...) que dans les structures profondes (cavernes, gouffres). Diverses hypothèses sont avancées en conclusion, pour tenter une approche d'explication sur la genèse des pseudo-karsts.
Organes hématopoïétiques et cellules sanguines chez Typhlonectes compressicaudus et Typhlonectes natans (Amphibien, Gymnophione)
Authors: Paillot R. , Estabel J. , Exbrayat Jean-Marie
Published: February 2017

Chez les Gymnophiones, la moelle osseuse est absente. Ce sont le foie, la rate et le thymus, principaux organes hématopoïétiques, qui sont à l'origine des cellules du système immunitaire. Ces cellules se répartissent au niveau des organes lymphoïdes et tissus lymphoïdes associés. Les Gymnophiones présentent donc une situation relativement primitive par rapport à l'organisation des organes hématopoïétiques des autres Amphibiens.
miR-181a Inhibits Cervical Cancer Development via Downregulating GRP78
Authors: Luo Chengyan , Qiu Jiangnan
Published: February 2017

Cervical cancer is among the most common cancers inflicting women worldwide. Understanding the pathological mechanisms of cervical cancer development is critical for identifying novel targets for cervical cancer treatment. MicroRNAs (miRs) have various roles in regulating cancer development.
In this study, we investigated the potential role of miR-181a and its target in regulating cervical cancer development and chemotherapy resistance. The expression of miR-181a was evaluated and modulated in several human cervical cancer cell lines. The role of miR-181a in regulating cervical
cancer growth and chemotherapy sensitivity was investigated in cell culture models and mouse tumor xenograft models. The target of miR-181a and its function were identified in cervical cancer models. We found a distinct expression profile for miR-181a in cervical cancer cell lines. Low expression
of miR-181a was closely related to cervical cancer growth and oxaliplatin resistance. HSPA5/GRP78 was identified as a target of miR-181a in cervical cancer cells. Upregulation of GRP78 led to a high cell proliferation rate and oxaliplatin resistance in cervical cancer models. In a retrospective
cervical cancer cohort, high GRP78 expression was correlated with poor survival. miR-181a suppressed cervical cancer development via downregulating GRP78. High expression of GRP78 is a tumor-promoting factor in cervical cancer and is thus a potential target for novel treatment.
Role of oxygen in wetting of copper nanoparticles on silicon surfaces at elevated temperature
Authors: Ghosh Tapas , Satpati Biswarup
Published: February 2017

Copper nanoparticles have been deposited on silicon surfaces by a simple galvanic displacement reaction, and rapid thermal annealing has been performed under various atmospheric conditions. In spite of the general tendency of the agglomeration of nanoparticles to lower the surface energy at elevated temperatures, our plan-view and cross-sectional transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) analysis shows that the thermal oxidation of the copper nanoparticles and formation of cupric oxide (CuO) on silicon surfaces leads to wetting rather than agglomeration. In contrast, agglomeration has been observed when copper nanoparticles were annealed in a nitrogen environment. The lattice transformation from cubic Cu to monoclinic CuO, and hence the change in surface energy of the particles, assists the wetting process. The occurrence of wetting during the oxidation step implies a strong interaction between the oxidized film and the silicon surface.
High-latitude Conic Current Sheets in the Solar Wind
Authors: Khabarova Olga V. , Malova Helmi V. , Kislov Roman A. , Zelenyi Lev M. , Obridko Vladimir N. , Kharshiladze Alexander F. , Tokumaru Munetoshi , Sokół Justyna M. , Grzedzielski Stan , Fujiki Ken’ichi
Published: February 2017

We provide observational evidence for the existence of large-scale cylindrical (or conic-like) current sheets (CCSs) at high heliolatitudes. Long-lived CCSs were detected by Ulysses during its passages over the South Solar Pole in 1994 and 2007. The characteristic scale of these tornado-like structures is several times less than a typical width of coronal holes within which the CCSs are observed. CCS crossings are characterized by a dramatic decrease in the solar wind speed and plasma beta typical for predicted profiles of CCSs. Ulysses crossed the same CCS at different heliolatitudes at 2–3 au several times in 1994, as the CCS was declined from the rotation axis and corotated with the Sun. In 2007, a CCS was detected directly over the South Pole, and its structure was strongly highlighted by the interaction with comet McNaught. Restorations of solar coronal magnetic field lines reveal the occurrence of conic-like magnetic separators over the solar poles in both 1994 and 2007. Such separators exist only during solar minima. Interplanetary scintillation data analysis confirms the presence of long-lived low-speed regions surrounded by the typical polar high-speed solar wind in solar minima. Energetic particle flux enhancements up to several MeV/nuc are observed at edges of the CCSs. We built simple MHD models of a CCS to illustrate its key features. The CCSs may be formed as a result of nonaxiality of the solar rotation axis and magnetic axis, as predicted by the Fisk–Parker hybrid heliospheric magnetic field model in the modification of Burger and coworkers.
Accretion of Saturn’s Inner Mid-sized Moons from a Massive Primordial Ice Ring
Authors: Salmon J. , Canup R. M.
Published: February 2017

Saturn’s rings are rock-poor, containing 90%–95% ice by mass. As a group, Saturn’s moons interior to and including Tethys are also about 90% ice. Tethys itself contains

rock by mass, in contrast to its similar-mass outer neighbor Dione, which contains

rock. Here we simulate the evolution of a massive primordial ice-rich ring and the production of satellites as ring material spreads beyond the Roche limit. We describe the Roche-interior ring with an analytic model, and use an N-body code to describe material beyond the Roche limit. We track the accretion and interactions of spawned satellites, including tidal interaction with the planet, assuming a tidal dissipation factor for Saturn of

. We find that ring torques and capture of moons into mutual resonances produce a system of ice-rich inner moons that extends outward to approximately Tethys’s orbit in 109 years, even with relatively slow orbital expansion due to tides. The resulting mass and semimajor axis distribution of spawned moons resembles that of Mimas, Enceladus, and Tethys. We estimate the mass of rock delivered to the moons by external cometary impactors during a late heavy bombardment. We find that the inner moons receive a mass in rock comparable to their current total rock content, while Dione and Rhea receive an order-of-magnitude less rock than their current rock content. This suggests that external contamination may have been the primary source of rock in the inner moons, and that Dione and Rhea formed from much more rock-rich source material. Reproducing the distribution of rock among the current inner moons is challenging, and appears to require large impactors stochasticity and/or the presence of some rock in the initial ring.
X-Ray Reflection and an Exceptionally Long Thermonuclear Helium Burst from IGR J17062-6143
Authors: Keek L. , Iwakiri W. , Serino M. , Ballantyne D. R. , Zand J. J. M. in’t , Strohmayer T. E.
Published: February 2017

Thermonuclear X-ray bursts from accreting neutron stars power brief but strong irradiation of their surroundings, providing a unique way to study accretion physics. We analyze MAXI/Gas Slit Camera and Swift/XRT spectra of a day-long flash observed from IGR J17062-6143 in 2015. It is a rare case of recurring bursts at a low accretion luminosity of 0.15% Eddington. Spectra from MAXI, Chandra, and NuSTAR observations taken between the 2015 burst and the previous one in 2012 are used to determine the accretion column. We find it to be consistent with the burst ignition column of 5 × 1010 g cm−2, which indicates that it is likely powered by burning in a deep helium layer. The burst flux is observed for over a day, and decays as a straight power law: F ∝ t
−1.15. The burst and persistent spectra are well described by thermal emission from the neutron star, Comptonization of this emission in a hot optically thin medium surrounding the star, and reflection off the photoionized accretion disk. At the burst peak, the Comptonized component disappears, when the burst may dissipate the Comptonizing gas, and it returns in the burst tail. The reflection signal suggests that the inner disk is truncated at ∼102 gravitational radii before the burst, but may move closer to the star during the burst. At the end of the burst, the flux drops below the burst cooling trend for 2 days, before returning to the pre-burst level.
A Spectroscopic Orbit for the Late-type Be Star β CMi
Authors: Dulaney Nicholas A. , Richardson Noel D. , Gerhartz Cody J. , Bjorkman J. E. , Bjorkman K. S. , Carciofi Alex C. , Klement Robert , Wang Luqian , Morrison Nancy D. , Bratcher Allison D. , Greco Jennifer J. , Hardegree-Ullman Kevin K. , Lembryk Ludwik , Oswald Wayne L. , Trucks Jesica L.
Published: February 2017

The late-type Be star β CMi is remarkably stable compared to other Be stars that have been studied. This has led to a realistic model of the outflowing Be disk by Klement et al. These results showed that the disk is likely truncated at a finite radius from the star, which Klement et al. suggest is evidence for an unseen binary companion in orbit. Here we report on an analysis of the Ritter Observatory spectroscopic archive of β CMi to search for evidence of the elusive companion. We detect periodic Doppler shifts in the wings of the Hα line with a period of 170 days and an amplitude of 2.25 km s−1, consistent with a low-mass binary companion (M ≈ 0.42 M
⊙). We then compared small changes in the violet-to-red peak height changes (V/R) with the orbital motion. We find weak evidence that it does follow the orbital motion, as suggested by recent Be binary models by Panoglou et al. Our results, which are similar to those for several other Be stars, suggest that β CMi may be a product of binary evolution where Roche lobe overflow has spun up the current Be star, likely leaving a hot subdwarf or white dwarf in orbit around the star. Unfortunately, no direct sign of this companion star is found in the very limited archive of International Ultraviolet Explorer spectra.
Pulsator-like Spectra from Ultraluminous X-Ray Sources and the Search for More Ultraluminous Pulsars
Authors: Pintore F. , Zampieri L. , Stella L. , Wolter A. , Mereghetti S. , Israel G. L.
Published: February 2017

Ultraluminous X-ray sources (ULXs) are a population of extragalactic objects whose luminosity exceeds the Eddington limit for a 10 M
⊙ black hole (BH). Their properties have been widely interpreted in terms of accreting stellar-mass or intermediate-mass BHs. However at least three neutron stars (NSs) have been recently identified in ULXs through the discovery of periodic pulsations. Motivated by these findings we studied the spectral properties of a sample of bright ULXs using a simple continuum model which was extensively used to fit the X-ray spectra of accreting magnetic NSs in the Galaxy. We found that such a model, consisting of a power-law with a high-energy exponential cut-off, fits most of the ULX spectra analyzed here very well, at a level comparable to that of models involving an accreting BH. On these grounds alone we suggest that other non-pulsating ULXs may host NSs. We also found that above 2 keV the spectrum of known pulsating ULXs is harder than that of the majority of the other ULXs of the sample, with only IC 342 X-1 and Ho IX X-1 displaying spectra of comparable hardness. We thus suggest that these two ULXs may host an accreting NS and encourage searches for periodic pulsations in the flux.
Occultations of Astrophysical Radio Sources as Probes of Planetary Environments: A Case Study of Jupiter and Possible Applications to Exoplanets
Authors: Withers Paul , Vogt Marissa F.
Published: February 2017

Properties of planetary atmospheres, ionospheres, and magnetospheres are difficult to measure from Earth. Radio occultations are a common method for measuring these properties, but they traditionally rely on radio transmissions from a spacecraft near the planet. Here, we explore whether occultations of radio emissions from a distant astrophysical radio source can be used to measure magnetic field strength, plasma density, and neutral density around planets. In a theoretical case study of Jupiter, we find that significant changes in polarization angle due to Faraday rotation occur for radio signals that pass within 10 Jupiter radii of the planet and that significant changes in frequency and power occur from radio signals that pass through the neutral atmosphere. There are sufficient candidate radio sources, such as pulsars, active galactic nuclei, and masers, that occultations are likely to occur at least once per year. For pulsars, time delays in the arrival of their emitted pulses can be used to measure plasma density. Exoplanets, whose physical properties are very challenging to observe, may also occult distant astrophysical radio sources, such as their parent stars.
X-Ray Spectral Properties of Seven Heavily Obscured Seyfert 2 Galaxies
Authors: Marchesi S. , Ajello M. , Comastri A. , Cusumano G. , Parola V. La , Segreto A.
Published: February 2017

We present the combined Chandra and Swift-BAT spectral analysis of seven Seyfert 2 galaxies selected from the Swift-BAT 100 month catalog. We selected nearby (z ≤ 0.03) sources lacking a ROSAT counterpart that never previously been observed with Chandra in the 0.3–10 keV energy range, and targeted these objects with 10 ks Chandra ACIS-S observations. The X-ray spectral fitting over the 0.3–150 keV energy range allows us to determine that all the objects are significantly obscured, with N
H ≥ 1023 cm−2 at a >99% confidence level. Moreover, one to three sources are candidate Compton-thick Active Galactic Nuclei (CT-AGNs; i.e., N
H ≥ 1024 cm−2). We also test the recent spectral curvature method developed by Koss et al. to find candidate CT-AGNs, finding a good agreement between our results and their predictions. Because the selection criteria we adopted were effective in detecting highly obscured AGNs, further observations of these and other Seyfert 2 galaxies selected from the Swift-BAT 100 month catalog will allow us to create a statistically significant sample of highly obscured AGNs, therefore providing a better understanding of the physics of the obscuration processes.
Candidate Water Vapor Lines to Locate the H2O Snowline Through High-dispersion Spectroscopic Observations. II. The Case of a Herbig Ae Star
Authors: Notsu Shota , Nomura Hideko , Ishimoto Daiki , Walsh Catherine , Honda Mitsuhiko , Hirota Tomoya , Millar T. J.
Published: February 2017

Observationally measuring the location of the

H

2

O

snowline is crucial for understanding planetesimal and planet formation processes, and the origin of water on Earth. In disks around Herbig Ae stars (T
* ∼ 10,000 K, M
* ≳ 2.5M
⊙), the position of the

H

2

O

snowline is farther from the central star compared with that around cooler and less massive T Tauri stars. Thus, the

H

2

O

emission line fluxes from the region within the

H

2

O

snowline are expected to be stronger. In this paper, we calculate the chemical composition of a Herbig Ae disk using chemical kinetics. Next, we calculate the

H

2

O

emission line profiles and investigate the properties of candidate water lines across a wide range of wavelengths (from mid-infrared to submillimeter) that can locate the position of the

H

2

O

snowline. Those lines identified have small Einstein A coefficients (

∼

10

−
6

–

10

−
3

s−1) and relatively high upper-state energies (∼1000 K). The total fluxes tend to increase with decreasing wavelengths. We investigate the possibility of future observations (e.g., ALMA, SPICA/SMI-HRS) locating the position of the

H

2

O

snowline. Since the fluxes of those identified lines from Herbig Ae disks are stronger than those from T Tauri disks, the possibility of a successful detection is expected to increase for a Herbig Ae disk.
The Next Generation Virgo Cluster Survey (NGVS). XXIV. The Red Sequence to ∼106 L⊙ and Comparisons with Galaxy Formation Models
Authors: Roediger Joel C. , Ferrarese Laura , Côté Patrick , MacArthur Lauren A. , Sánchez-Janssen Rúben , Blakeslee John P. , Peng Eric W. , Liu Chengze , Munoz Roberto , Cuillandre Jean-Charles , Gwyn Stephen , Mei Simona , Boissier Samuel , Boselli Alessandro , Cantiello Michele , Courteau Stéphane , Duc Pierre-Alain , Lançon Ariane , Mihos J. Christopher , Puzia Thomas H. , Taylor James E. , Durrell Patrick R. , Toloba Elisa , Guhathakurta Puragra , Zhang Hongxin
Published: February 2017

We use deep optical photometry from the Next Generation Virgo Cluster Survey (NGVS) to investigate the color–magnitude diagram for the galaxies inhabiting the core of this cluster. The sensitivity of the NGVS imaging allows us to continuously probe galaxy colors over a factor of ∼2 × 105 in luminosity, from brightest cluster galaxies to scales overlapping classical satellites of the Milky Way (

M

g
′

 ∼ −9; M
* ∼ 106
M
⊙), within a single environment. Remarkably, we find the first evidence that the red sequence (RS) flattens in all colors at the faint-magnitude end (starting between −14 ≤ 

M

g
′

 ≤ −13, around M
* ∼ 4 × 107
M
⊙), with the slope decreasing to ∼60% or less of its value at brighter magnitudes. This could indicate that the stellar populations of faint dwarfs in Virgo’s core share similar characteristics (e.g., constant mean age) over ∼3 mag in luminosity, suggesting that these galaxies were quenched coevally, likely via pre-processing in smaller hosts. We also compare our results to galaxy formation models, finding that the RS in model clusters have slopes at intermediate magnitudes that are too shallow, and in the case of semianalytic models, do not reproduce the flattening seen at both extremes (bright/faint) of the Virgo RS. Deficiencies in the chemical evolution of model galaxies likely contribute to the model-data discrepancies at all masses, while overly efficient quenching may also be a factor at dwarf scales. Deep UV and near-IR photometry are required to unambiguously diagnose the cause of the faint-end flattening.
Magnetic Separatrix as the Source Region of the Plasma Supply for an Active-region Filament
Authors: Zou P. , Fang C. , Chen P. F. , Yang K. , Cao Wenda
Published: February 2017

Solar filaments can be formed via chromospheric evaporation followed by condensation in the corona or by the direct injection of cool plasma from the chromosphere to the corona. We here confirm with high-resolution Hα data observed by the 1.6 m New Solar Telescope of the Big Bear Solar Observatory on 2015 August 21 that an active-region filament is maintained by the continuous injection of cold chromospheric plasma. We find that the filament is rooted along a bright ridge in Hα, which corresponds to the intersection of a magnetic quasi-separatrix layer with the solar surface. This bright ridge consists of many small patches whose sizes are comparable to the width of the filament threads. It is found that upflows originate from the brighter patches of the ridge, whereas the downflows move toward the weaker patches of the ridge. The whole filament is composed of two opposite-direction streams, implying that longitudinal oscillations are not the only cause of the counterstreamings, and unidirectional siphon flows with alternative directions are another possibility.
CO-Dark Star Formation and Black Hole Activity in 3C 368 at z = 1.131: Coeval Growth of Stellar and Supermassive Black Hole Masses∗
†
Authors: Lamarche C. , Stacey G. , Brisbin D. , Ferkinhoff C. , Hailey-Dunsheath S. , Nikola T. , Riechers D. , Sharon C. E. , Spoon H. , Vishwas A.
Published: February 2017

We present the detection of four far-infrared fine-structure oxygen lines, as well as strong upper limits for the CO(2–1) and [N ii] 205 μm lines, in 3C 368, a well-studied radio-loud galaxy at z = 1.131. These new oxygen lines, taken in conjunction with previously observed neon and carbon fine-structure lines, suggest a powerful active galactic nucleus (AGN), accompanied by vigorous and extended star formation. A starburst dominated by O8 stars, with an age of ∼6.5 Myr, provides a good fit to the fine-structure line data. This estimated age of the starburst makes it nearly concurrent with the latest episode of AGN activity, suggesting a link between the growth of the supermassive black hole and stellar population in this source. We do not detect the CO(2–1) line, down to a level twelve times lower than the expected value for star-forming galaxies. This lack of CO line emission is consistent with recent star formation activity if the star-forming molecular gas has low metallicity, is highly fractionated (such that CO is photodissociated throughout much of the clouds), or is chemically very young (such that CO has not yet had time to form). It is also possible, although we argue it is unlikely, that the ensemble of fine-structure lines is emitted from the region heated by the AGN.
Discovery and Precise Characterization by the MEarth Project of LP 661-13, an Eclipsing Binary Consisting of Two Fully Convective Low-mass Stars
Authors: Dittmann Jason A. , Irwin Jonathan M. , Charbonneau David , Berta-Thompson Zachory K. , Newton Elisabeth R. , Latham David W. , Latham Christian A. , Esquerdo Gilbert , Berlind Perry , Calkins Michael L
Published: February 2017

We report the detection of stellar eclipses in the LP 661-13 system. We present the discovery and characterization of this system, including high-resolution spectroscopic radial velocities and a photometric solution spanning two observing seasons. LP 661-13 is a low-mass binary system with an orbital period of

days at a distance of 24.9 ± 1.3 parsecs. LP 661-13A is a 0.30795 ± 0.00084 M
⊙ star, while LP 661-13B is a 0.19400 ± 0.00034 M
⊙ star. The radius of each component is 0.3226 ± 0.0033 R
⊙ and 0.2174 ± 0.0023 R
⊙, respectively. We detect out-of-eclipse modulations at a period slightly shorter than the orbital period, implying that at least one of the components is not rotating synchronously. We find that each component is slightly inflated compared to stellar models, and that this cannot be reconciled through age or metallicity effects. As a nearby eclipsing binary system, where both components are near or below the full-convection limit, LP 661-13 will be a valuable test of models for the structure of cool dwarf stars.
Planck Lensing and Cosmic Infrared Background Cross-correlation with Fermi-LAT: Tracing Dark Matter Signals in the Gamma-Ray Background
Authors: Feng Chang , Cooray Asantha , Keating Brian
Published: February 2017

The extragalactic γ-ray background and its spatial anisotropy could potentially contain a signature of dark matter (DM) annihilation or particle decay. Astrophysical foregrounds, such as blazars and star-forming galaxies (SFGs), however, dominate the γ-ray background, precluding an easy detection of the signal associated with the DM annihilation or decay in the background intensity spectrum. The DM imprint on the γ-ray background is expected to be correlated with large-scale structure tracers. In some cases, such a cross-correlation is even expected to have a higher signal-to-noise ratio than the auto-correlation. One reliable tracer of the DM distribution in the large-scale structure is lensing of the cosmic microwave background (CMB), and the cosmic infrared background (CIB) is a reliable tracer of SFGs. We analyze Fermi-LAT data taken over 92 months and study the cross-correlation with Planck CMB lensing, Planck CIB, and Fermi-γ maps. We put upper limits on the DM annihilation cross-section from the cross-power spectra with the γ-ray background anisotropies. The unbiased power spectrum estimation is validated with simulations that include cross-correlated signals. We also provide a set of systematic tests and show that no significant contaminations are found for the measurements presented here. Using γ-ray background map from data gathered over 92 months, we find the best constraint on the DM annihilation with a

1
σ

confidence level upper limit of 10−25–10−24 cm3 s−1, when the mass of DM particles is between 20 and 100 GeV.
Constraining the Stellar Populations and Star Formation Histories of Blue Compact Dwarf Galaxies with SED Fits
Authors: Janowiecki Steven , Salzer John J. , Zee Liese van , Rosenberg Jessica L. , Skillman Evan
Published: February 2017

We discuss and test possible evolutionary connections between blue compact dwarf galaxies (BCDs) and other types of dwarf galaxies. BCDs provide ideal laboratories to study intense star formation episodes in low-mass dwarf galaxies, and have sometimes been considered a short-lived evolutionary stage between types of dwarf galaxies. To test these connections, we consider a sample of BCDs as well as a comparison sample of nearby galaxies from the Local Volume Legacy (LVL) survey for context. We fit the multi-wavelength spectral energy distributions (SED, far-ultra-violet to far-infrared) of each galaxy with a grid of theoretical models to determine their stellar masses and star formation properties. We compare our results for BCDs with the LVL galaxies to put BCDs in the context of normal galaxy evolution. The SED fits demonstrate that the star formation events currently underway in BCDs are at the extreme of the continuum of normal dwarf galaxies, both in terms of the relative mass involved and in the relative increase over previous star formation rates. Today’s BCDs are distinctive objects in a state of extreme star formation that is rapidly transforming them. This study also suggests ways to identify former BCDs whose star formation episodes have since faded.
The Dependence of Cluster Galaxy Properties on the Central Entropy of Their Host Cluster
Authors: Kim Jae-Woo , Ko Jongwan , Hwang Ho Seong , Edge Alastair C. , Lee Joon Hyeop , Lee Jong Chul , Jeong Hyunjin
Published: February 2017

We present a study of the connection between brightest cluster galaxies (BCGs) and their host galaxy clusters. Using galaxy clusters at

from the Hectospec Cluster Survey (HeCS) with X-ray information from the Archive of Chandra Cluster Entropy Profile Tables (ACCEPT), we confirm that BCGs in low central entropy clusters are well aligned with the X-ray center. Additionally, the magnitude difference between BCG and the second brightest galaxy also correlates with the central entropy of the intracluster medium. From the red-sequence (RS) galaxies, we cannot find significant dependence of RS color scatter and stellar population on the central entropy of the intracluster medium of their host cluster. However, BCGs in low-entropy clusters are systematically less massive than those in high-entropy clusters, although this is dependent on the method used to derive the stellar mass of BCGs. In contrast, the stellar velocity dispersion of BCGs shows no dependence on BCG activity and cluster central entropy. This implies that the potential of the BCG is established earlier and the activity leading to optical emission lines is dictated by the properties of the intracluster medium in the cluster core.
Fundamental Plane of Black Hole Activity in the Quiescent Regime
Authors: Xie Fu-Guo , Yuan Feng
Published: February 2017

A correlation among the radio luminosity (

L

R

), X-ray luminosity (

L

X

), and black hole (BH) mass (

M

BH

) in active galactic nuclei (AGNs) and BH binaries is known to exist and is called the “fundamental plane” of BH activity. Yuan & Cui predict that the radio/X-ray correlation index,

ξ

X

, changes from

ξ

X

≈
0.6

to

ξ

X

≈
1.2
–
1.3

when

L

X

/

L

Edd

decreases below a critical value of 

∼

10

−
6

. While many works favor such a change, there are also several works claiming the opposite. In this paper, we gather from the literature the largest quiescent AGN (defined as

L

X

/

L

Edd

≲

10

−
6

) sample to date, consisting of 75 sources. We find that these quiescent AGNs follow a

ξ

X

≈
1.23

radio/X-ray relationship, in excellent agreement with the Yuan & Cui prediction. The reason for the discrepancy between the present result and some previous works is that their samples contain not only quiescent sources but also “normal” ones (i.e.,

L

X

/

L

Edd

≳

10

−
6

). In this case, the quiescent sources will mix up with those normal ones in

L

R

and

L

X

. The value of

ξ

X

will then be between 0.6 and ∼1.3, with the exact value being determined by the sample composition, i.e., the fraction of the quiescent and normal sources. Based on this result, we propose that a more physical way to study the fundamental plane is to replace

L

R

and

L

X

with

L

R

/

L

Edd

and

L

X

/

L

Edd

, respectively.
Evolutions and Calibrations of Long Gamma-Ray-burst Luminosity Correlations Revisited
Authors: Wang Guo-Jian , Yu Hai , Li Zheng-Xiang , Xia Jun-Qing , Zhu Zong-Hong
Published: February 2017

Luminosity correlations of long gamma-ray bursts (GRBs) are extensively proposed as an effective complementarity to trace the Hubble diagram of the universe at high redshifts, which is of great importance to explore properties of dark energy. Recently, several empirical luminosity correlations have been statistically proposed from GRB observations. However, to treat a GRB as the distance indicator, there are two key issues: the redshift evolution of luminosity correlations and their calibrations. In this paper, we choose the Amati relation, the correlation between the peak spectra energy and the equivalent isotropic energy of GRBs (

E

p

–

E

iso

) as an example and find that the current GRB data set implies that there could be a evolution of the luminosity correlation with respect to the redshift. Therefore, we propose an extended Amati relation with two extra redshift-dependent terms to correct the redshift evolution of the GRB relation. Second, we carefully check the reliability of the calibration method using the low-redshift GRB data. Importantly, we find that the low-redshift calibration method does not take whole correlations between

Ω

m

and coefficients into account. Neglecting this correlation information can break the degeneracies and obtain the biased constraint on

Ω

m

, which is very sensitive to values of parameters for the calibration. A small shift in the parameters of the “calibrated” relation could significantly change the final constraint on

Ω

m

in the low-redshift calibration method. Finally, we simulate several GRB samples with different statistical errors and find that, in order to correctly recover the fiducial value of

Ω

m

, using the low-redshift calibration method, we need a large number of GRB samples with high precisions.
The Effects of the Overshooting of the Convective Core on Main-sequence Turnoffs of Young- and Intermediate-age Star Clusters
Authors: Yang Wuming , Tian Zhijia
Published: February 2017

Recent investigations have shown that the extended main-sequence turnoffs (eMSTOs) are a common feature of intermediate-age star clusters in the Magellanic Clouds. The eMSTOs are also found in the color–magnitude diagram of young-age star clusters. The origin of the eMSTOs is still an open question. Moreover, asteroseismology shows that the value of the overshooting parameter

of the convective core is not fixed for the stars with an approximatelly equal mass. Thus the MSTO of star clusters may be affected by the overshooting of the convective core (OVCC). We calculated the effects of the OVCC with different δ
ov on the MSTO of young- and intermediate-age star clusters. If δ
ov varies between stars in a cluster, the observed eMSTOs of young- and intermediate-age star clusters can be explained well by the effects. The equivalent age spreads of MSTO caused by the OVCC are related to the age of star clusters and are in good agreement with observed results of many clusters. Moreover, the observed eMSTOs of NGC 1856 are reproduced by the coeval populations with different δ
ov. The eMSTOs of star clusters may be relevant to the effects of the OVCC. The effects of the OVCC are similar to that of rotation in some respects. However, the effects cannot result in a significant split of the main sequence of young star clusters at

. The presence of a rapid rotation can make the split of the main sequence of young star clusters more significant.
Laser-Assisted Capsulotomy Centration: A Prospective Trial Comparing Pupil Versus OCT-Based Scanned Capsule Centration
Authors: Schultz Tim , Tsiampalis Nikolaos , Dick H. Burkhard
Published: February 2017

PURPOSE:

To investigate different capsulotomy centration methods for femtosecond laser-assisted cataract surgery. The overlap between intraocular lens (IOL) optic and lens capsule was measured with different centration methods and IOL types.

METHODS:

This was a prospective randomized clinical trial. Patients with cataract scheduled for femtosecond laser-assisted cataract surgery were assigned to one of four treatment groups: optical coherence tomography (OCT)-based scanned capsule centration (SCC) and three-piece IOL (SCC with three-piece IOL); scanned capsule centration and plate-haptic IOL (SCC with plate-haptic IOL); pupil centration (PC) and three-piece IOL (PC with three-piece IOL); or PC and plate-haptic IOL (PC with plate-haptic IOL). At the end of surgery, the overlap between the IOL optic and capsular bag was measured.

RESULTS:

The results of 160 patients were evaluated (n = 40 in each group). There was no difference in age (
P
= .27), sex (
P
= .18), the number of treated left and right eyes (
P
= .64), or cataract grade (
P
= .06). With the new SCC method (capsulotomy diameter: 5 mm), a complete overlap was achieved in all cases in both SCC groups. The overlap was also complete in all cases with PC and plate-haptic IOLs. In the PC with three-piece IOL group, the overlap was incomplete in 3 eyes.

CONCLUSIONS:

The SCC method helps to achieve a 360° overlap in all eyes independent of the IOL type. A complete 360° overlap was achieved in all cases up to a calculated capsulotomy diameter of 5.1 mm with this new method.

[
J Refract Surg
. 2017;33(2):74–78.]
Use of Electronic Nicotine Delivery Systems Among Adolescents: Status of the Evidence and Public Health Recommendations
Authors: Kamat Aarti D. , Van Dyke Alison L.
Published: February 2017

Although the prevalence of tobacco smoking has been declining in recent years, the use of electronic nicotine delivery systems (ENDS) such as of electronic cigarettes, vaporizers, and hookahs has been steadily rising, especially among adolescents. ENDS are not only advertised to children, but their sale via the Internet has made them easily accessible to youth. In general, children perceive ENDS as safe, or at least safer than smoking traditional combustible tobacco products; however, exposure to nicotine may have deleterious effects on the developing brain. Concern also persists that ENDS may be a “starter” drug that may lead to further tobacco, drug, and/or alcohol use. In contrast to this precautionary stance that is associated with calls for legislative oversight of ENDS marketing and sales, harm reductionists claim that the risks posed by ENDS are minor in comparison with those of combustible tobacco products and that ENDS may be used as a means of nicotine replacement for smoking cessation, despite no concrete evidence to support this assertion. Many medical and health-related organizations have produced position statements concerning ENDS use, including among adolescents. This article summarizes the advantages and disadvantages of using ENDS espoused in these position statements, especially as they relate to use among adolescents.

[
Pediatr Ann
. 2017;46(2):e69–e77.]
Herpes Simplex Virus in the Neonate
Authors: Wang Amy , Wohrley Julie , Rosebush Julia
Published: February 2017

Neonatal herpes simplex virus (HSV) disease is a serious, life-threatening condition that should be considered in neonates with fever, vesicular rash, culture negative sepsis, and/or seizure activity. Because signs and symptoms of neonatal HSV may closely resemble those of bacterial sepsis, a thorough history and appropriate testing are imperative to accurately confirm the diagnosis. Failure to treat vesicular lesions from HSV in the neonate leads to an approximate 75% chance of progression to disseminated disease and/or meningoencephalitis. Therefore, prompt recognition of symptoms and institution of treatment pending results of the investigation are imperative to minimize the high rates of morbidity and mortality associated with this diagnosis.

[
Pediatr Ann
. 2017;46(2):e42–e46.]
Diagnosing Acute HIV Infection
Authors: Bottone Paul Devine , Bartlett Allison H.
Published: February 2017

Acute HIV infection (AHI) represents the first 6 to 12 weeks of the disease process, when the virus is aggressively replicating in the lymphoid tissues. Accordingly, high viral loads are often present during this phase, with declining lymphocyte levels, as the CD4+ T-cell subset is preferentially commandeered to facilitate viral reproduction. Detection at this stage is imperative—the affected are often unaware, but highly infectious. Unfortunately, correct diagnosis of AHI can be challenging because the more traditional, frequently used tests, which rely on antibody detection, will often produce false-negative results during the “window period” (usually 3 to 4 weeks from infection) due to slow production of HIV antibodies. Consequently, testing with fourth-generation antibody-antigen and viral nucleic acid polymerase chain reaction modalities, which can yield positive results within 5 to 7 days of infection, is vital in the context of any significant concern for AHI.

[
Pediatr Ann
. 2017;46(2):e47–e50.]
Usos y significados contemporáneos de la comida desde la antropología de la alimentación en América Latina y España
Authors: López García Julián , Mariano Juárez Lorenzo , Medina F. Xavier
Published: February 2017

En este artículo proponemos una revisión de la antropología de la alimentación en España y en Latinoamérica desde una perspectiva histórica reciente. El artículo analiza el origen de la antropología de la alimentación en España y Latinoamérica y sus dificultades para el asentamiento de esta especialidad en el contexto de la antropología sociocultural hasta nuestros días, con una revisión de los intereses temáticos presentes y emergentes. El artículo se organiza principalmente alrededor de tres ejes que agrupan las temáticas y tendencias de los profesionales que han trabajado en este campo: el patrimonio alimentario, entre localidad y globalización; carencias alimentarias; y simbolismos y significaciones alimentarias.
El canto del pastor no espanta las ovejas: memoria y nostalgia en los versos improvisados de los emigrantes vascos
Authors: Pérez Pío
Published: February 2017

El objetivo de este artículo es analizar la nostalgia que sufrieron los pastores vascos que emigraron a Estados Unidos mediante el análisis de su producción de versos improvisados. Estos versos improvisados abordaban sus añoranzas, sus deseos, opiniones e inquietudes de una manera enunciativa y emotiva, de una forma diferente de expresión que utilizan otros géneros narrativos, que tienden a proyectar esas emociones de manera más racionalizada. En el caso que nos ocupa, estos versos tienen una función testimonial, evocadora o emotiva que es perceptible de manera directa. Es decir, se erigen en textos evocadores complejos y multifacéticos que construyen la representación del proyecto migratorio.
Hoy en día sería unánime el acuerdo en considerar la literatura o el cine como productos culturales con una enorme relevancia social y que las representaciones que en esos productos culturales se reflejan son elaboraciones de unos discursos sociales e históricos. De la misma manera, estos versos vinculados con la emigración a América se constituyen como discursos sociales e históricos y como atalayas desde donde poder observar cómo se fue construyendo la realidad social de la emigración vasca.
Bailes boleros y flamencos en los primeros cortometrajes mudos. Narrativas y arquetipos sobre «lo español» en los albores del siglo XX
Authors: Cruces-Roldán Cristina
Published: February 2017

El artículo localiza y cataloga 37 filmaciones del periodo 1894-1910 que conforman un corpus de cine primitivo sobre bailes españoles, boleros y flamencos. Estas películas mudas fueron registradas en exposiciones universales o como resultado de dramatizaciones teatrales, parodias e historias de ficción y están contenidas en los archivos The Library of Congress, Gaumont-Pathé, las colecciones Pathé y Frères Lumière y los Huntley Films Archive. El análisis de contenido de estos archivos demuestra las potencialidades de la filmografía pionera como fuente documental para conocer los procesos de construcción y reproducción de los clichés nacionales. Se expone la coexistencia de dos narrativas en estos registros pioneros: la testimonial del baile como expresión artística, y el discurso identitario sobre «lo español» a través de las disposiciones corporales y los elementos ambientales de los fotogramas. El modo de representación del arquetipo hispánico confirma que el cine de los inicios fue una vía de transmisión continuista respecto a los imaginarios estéticos, psicológicos y morales insertos en la espagnolade, para los cuales etnicidad y género funcionaron como sustratos convertidos en cliché de una cultura periférica y, a la vez, fascinante.
La catarsis de los cuerpos grávidos. Experiencias de dolor y sufrimiento en el habitus del parto medicalizado
Authors: Hernández Garre José Manuel , Echevarría Pérez Paloma , Gomariz Sandoval María José
Published: February 2017

El artículo explora las experiencias maternas ligadas al dolor y el sufrimiento en el marco del parto medicalizado. La información se obtuvo a través de la realización de una serie de entrevistas semiestructuradas realizadas a madres y padres que habían sido atendidos en un centro sanitario de corte intervencionista. El análisis se hizo desde un posicionamiento culturista crítico con las representaciones somaticistas de dolor. Los resultados hablan de unas dinámicas asistenciales que favorecen la transformación del dolor en sufrimiento, realidad que junto con las cosmovisiones culturales de la tecnociencia, que lo catalogan como un sinsentido, llevan a las madres a un tratamiento farmacológico estandarizado. La conclusión es que existe una hegemonía de las representaciones en clave biologicista del dolor en los contextos clínicos, perspectivas desde las que no se contemplan sus dimensiones morales, sociales y funcionales; minusvalorando, así, otros afrontamientos no farmacológicos del mismo.
Diálogos y contrastes entre proyectos de desarrollo y modelos de salud. Experiencia y consideraciones en torno a los achuar de la Amazonía Ecuatoriana
Authors: Pulido-Fuentes Montserrat
Published: February 2017

La ejecución de un programa de salud entre el pueblo achuar de la Amazonía Ecuatoriana, bajo las lógicas de la cooperación al desarrollo y del modelo biomédico occidental, redefine el modelo de salud de la sociedad en la que interviene; así como a sus agentes de salud. Las capacitaciones, las infraestructuras, los preceptos e indicaciones contribuyen en la construcción de un prototipo que relega la práctica terapéutica tradicional, las diferentes categorías de males, así como las explicaciones derivadas sobre el origen de las enfermedades, a pesar de mantener un discurso crítico y un marco teórico que busca la integración de todos los modelos. El presente artículo, trata de aproximarse al proceso de salud-enfermedad-atención de la población achuar, analizando las relaciones que se presentan entre los diferentes actores que participan en dicho proceso. Se analiza la aplicación de un proyecto de promoción de la salud, la emergencia de respuestas y estrategias tanto acomodaticias como de resistencia local. La etnografía recapitulada, trata de mostrar algunas reflexiones sobre la fragilidad en la formulación e implementación de programas de salud, al perdurar la falta de perspectiva local, así como la perspectiva del estado. También se muestran otras competencias culturales que apelan a la inclusión de estos grupos y de sus terapias en las políticas sanitarias, y no solo de forma retórica o como proyectos políticos, —más allá de un mero rescate ideológico. A pesar de todo, se describe la inevitable hibridación y necesaria negociación entre los actores implicados en el proceso.
En la línea de fuego: Construcción de masculinidades en jóvenes tamaulipecos ligados al narco
Authors: Córdova Plaza Rosío , Hernández Sánchez Ernesto
Published: February 2017

Este artículo busca examinar las condiciones en las que construyen su masculinidad varones jóvenes que se dedican a las labores de vigilancia y seguridad para los cárteles del narcotráfico, conocidos como «halcones». Analiza la experiencia etnográfica recabada en dos espacios: la Ciudad de Mante, Tamaulipas, y el penal de Coatzacoalcos, Veracruz. Se muestran las formas de reclutamiento, operación y funciones de estos jóvenes y el significado que tiene para sus identidades de género el trabajo con las mafias. Asimismo, se realiza una reflexión sobre la etnografía en contextos de violencia y se propone que herramientas como la ciberetnografía y los sitios web especializados en el tema y sus foros de discusión, son una fuente directa de información con individuos fuera de la ley.
The effects of heavy metal concentration on bio-accumulation, productivity and pigment content of two species of marine macro algae
Authors: Wickramasinghe W. A. Anusha D. L. , Mubiana Valentine K. , Blust Ronny
Published: February 2017

Environmental pollution due to heavy metals is a world-wide problem in estuarine, coastal and marine waters. Metal pollution affects different organisms in different ways and the degree of the impact is site-specific. Aim of the present study was to determine the effects of heavy metals viz., Cu, Cd and Pb exposure on tissue accumulation, pigmentation and productivity of two marine macro algae, Fucus vesiculosus and Ulva lactuca under controlled laboratory conditions. Algae were collected from a reference location, Wemeldinge in the Eastern Scheldet Estuary in Netherlands. Metal concentrations were determined using ICP-MS. Productivity of algae was measured using Winkler method and the results were expressed as carbon equivalent. Pigment profiles of two species were analyzed by spectral absorbance over 250 -1100nm range. The results revealed that the metal accumulation in tissues significantly increased with increasing exposure to metal concentration whereas, pigmentation, and photosynthetic productivity decreased with increasing metal concentration. Hence, F. vesiculosus and U. lactuca could be used as bio-indicators to determine metal pollution in coastal waters.