bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Quantitative Approach To Characterize Porosity Structure From Borehole Electrical Images and Its Application in a Carbonate Reservoir in the Tazhong Area, Tarim Basin
Authors: Hai-cheng Fu , Chang-chun Zou , Ning Li , Cheng-wen Xiao , Cheng-sen Zhang , Xing-neng Wu , Rui-lin Liu 
Published: January 2016

Summary
For a carbonate reservoir that has low porosity, its validity cannot simply be measured by its total porosity. Therefore, one must find more-effective porosity parameters to indicate reservoir validity. Two parameters that reflect the porosity spectrum's shape are proposed in this paper to characterize the porosity structure from borehole electrical images. One is the length of the right-porosity spectrum (LRPS), and the other is the root mean square (RMS) of the right-porosity spectrum (RMSRPS). Subsequently, the validity of a carbonate reservoir was considered by use of these two parameters. The logging evaluation, processing, and interpretation of multiple wells in a fractured/vuggy reservoir with low porosity in the Tarim Basin indicate that these two parameters reflect the variation of pore structures better than conventional methods, and they agree better with the well-test results.
Recycling Fracturing Flowback Water for Use in Hydraulic Fracturing: Influence of Organic Matter on Stability of Carboxyl-Methyl-Cellulose-Based Fracturing Fluids
Authors: Esmaeilirad N.. , Terry C.. , Kennedy Herron , Prior A.. , Carlson K.. 
Published: January 2016

SummaryRecycling oilfield wastewater for hydraulic fracturing requires a good understanding of the water chemical characteristics and how these interact with the fracturing fluid. The viscosity and rheological properties of fracturing fluids affect proppant placement, length and width of fractures, fracture conductivity, and, consequently, the success of the treatment. The objective of the research described here was to understand if dissolved organic matter (DOM) at high concentrations influences subsequent fracturing with a gelled fluid. Experimental studies were conducted on four types of water: (1) model water with low DOM, (2) recycled water from an industrial-treatment facility (medium DOM), (3) untreated early-time flowback (ETFB) water (high DOM), and (4) untreated produced water (high DOM). A low-pH, zirconium-crosslinker-gelled fluid at 200°F was examined in the study. All three water samples that had significant levels of organic matter [total organic content (TOC) &gt; 1000 mg/L] exhibited lower peak viscosities and more-rapid viscosity decay than the model water without organic matter. The destabilizing influence of organic matter on carboxyl methyl cellulose (CMC) gelled fracturing-fluid viscosity is thought to be caused by secondary crosslinking of the short-chain polymer residuals in the flowback, resulting in lower initial viscosity and stability.
Cost of Capital Free-Riders
Authors: Baginski Stephen P. , Hinson Lisa A. 
Published: January 2016

ABSTRACT
We document the interrelationship of disclosure policy decisions among firms by providing evidence that the cessation of quarterly management forecast guidance by 656 firms (“stoppers”) during 2004–2009 is associated with a pursuant increase in quarterly forecasts by previously non-forecasting firms in the same industries (“free-riders”). Increased forecasting by free-riders is positively associated with the information loss in the industry (proxied by the number of stoppers in the industry, the strength of previously existing information transfer relations between stoppers and free-riders, and whether stoppers and free-riders are peer firms) and the importance of the information loss to the free-riders (proxied by analyst following and the existence of new share issues). Following the cessation event, free-riders' cost of capital decreases as a function of the extent to which free-riders immediately initiate quarterly forecasting.
JEL Classifications: M41.
Data Availability: Data are available from the sources indicated in the text.
Does Ownership Structure Affect Labor Decisions?
Authors: Hall Curtis M. 
Published: January 2016

ABSTRACT
This study examines how the incentives related to ownership structure influence labor cost management decisions in publicly traded and privately held organizations. I document that public banks have more elastic labor cost structures than private banks, which suggests that public bank managers prefer greater flexibility to remove labor resources when desired. Consistent with public banks facing greater financial reporting pressures, I find that they reduce labor costs to avoid earnings declines. However, I also find that the use of labor cost reductions to manage required regulatory capital is more pronounced in private banks. Consistent with the explanation that access to the equity markets allows public firms to sell equity in lieu of cutting costs, I find that the use of labor cost reductions to manage capital requirements is concentrated in the subsample of banks with lower equity issuances. These findings suggest that while public ownership induces financial reporting pressure, it may also alleviate regulatory pressure through greater ability to sell equity.
Conceptual metaphors in Ukrainian prime ministers’ discourse involving renewables
Authors: Kapranov Oleksandr 
Published: January 2016

Abstract
This qualitative study is aimed at elucidating conceptual metaphors associated with renewable energy sources (further referred to as ‘renewables’) in Ukrainian prime ministers’ (PMs) political discourse. The material derives from a corpus of Ukrainian PMs’ political texts on renewables in Ukraine within the timeframe 2005-2014. The corpus is examined for the presence of conceptual metaphors pertaining to the topic of renewables. Data analysis indicates that from 2005 to 2013 conceptual metaphors involving renewables are embedded in the issues of Ukraine’s adherence to the Kyoto Protocol, the EU directives on renewables, the monetary value of renewables and the role of renewables in Ukraine’s energy security, thus instantiating the conceptual metaphors Renewables as Ukraine’s European Choice, Renewables as a Path to the EU, Renewables as Money and Renewables as Independence respectively. However, the novel metaphor Renewables as Survival is identified in PM Yatsenjuk’s political discourse in 2014. This metaphor is embedded in the context of another conceptual metaphor, Gas as a Weapon, which is present in political discourse involving Russian natural gas export to third countries. Data analysis indicates that the conceptual metaphors Renewables as Survival and Renewables as Independence are in a polyphonic relationship of synergy and contrast with Gas as a Weapon.
POLARIZATION EVOLUTION OF EARLY OPTICAL AFTERGLOWS OF GAMMA-RAY BURSTS
Authors: Lan Mi-Xiang , Wu Xue-Feng , Dai Zi-Gao 
Published: January 2016

ABSTRACT
The central engine and jet composition of gamma-ray bursts (GRBs) remain mysterious. Here we suggest that observations on the polarization evolution of early optical afterglows may shed light on these questions. We first study the dynamics of a reverse shock and a forward shock that are generated during the interaction of a relativistic jet and its ambient medium. The jet is likely magnetized with a globally large-scale magnetic field from the central engine. The existence of the reverse shock requires that the magnetization degree of the jet should not be high (σ ≤ 1), so that the jet is mainly composed of baryons and leptons. We then calculate the light curves and polarization evolution of early optical afterglows and find that when the polarization position angle changes by 90° during the early afterglow, the polarization degree is zero for a toroidal magnetic field but is very likely to be nonzero for an aligned magnetic field. This result would be expected to provide a probe for the central engine of GRBs because an aligned field configuration could originate from a magnetar central engine and a toroidal field configuration could be produced from a black hole via the Blandford–Znajek mechanism. Finally, for such two kinds of magnetic field configurations, we fit the observed data of the early optical afterglow of GRB 120308A equally well.
THE SEGUE K GIANT SURVEY. III. QUANTIFYING GALACTIC HALO SUBSTRUCTURE
Authors: Janesh William , Morrison Heather L. , Ma Zhibo , Rockosi Constance , Starkenburg Else , Xue Xiang Xiang , Rix Hans-Walter , Harding Paul , Beers Timothy C. , Johnson Jennifer , Lee Young Sun , Schneider Donald P. 
Published: January 2016

ABSTRACT
We statistically quantify the amount of substructure in the Milky Way stellar halo using a sample of 4568 halo K giant stars at Galactocentric distances ranging over 5–125 kpc. These stars have been selected photometrically and confirmed spectroscopically as K giants from the Sloan Digital Sky Survey’s Sloan Extension for Galactic Understanding and Exploration project. Using a position–velocity clustering estimator (the 4distance) and a model of a smooth stellar halo, we quantify the amount of substructure in the halo, divided by distance and metallicity. Overall, we find that the halo as a whole is highly structured. We also confirm earlier work using blue horizontal branch (BHB) stars which showed that there is an increasing amount of substructure with increasing Galactocentric radius, and additionally find that the amount of substructure in the halo increases with increasing metallicity. Comparing to resampled BHB stars, we find that K giants and BHBs have similar amounts of substructure over equivalent ranges of Galactocentric radius. Using a friends-of-friends algorithm to identify members of individual groups, we find that a large fraction (∼33%) of grouped stars are associated with Sgr, and identify stars belonging to other halo star streams: the Orphan Stream, the Cetus Polar Stream, and others, including previously unknown substructures. A large fraction of sample K giants (more than 50%) are not grouped into any substructure. We find also that the Sgr stream strongly dominates groups in the outer halo for all except the most metal-poor stars, and suggest that this is the source of the increase of substructure with Galactocentric radius and metallicity.
A MATURE GALAXY CLUSTER AT z = 1.58 AROUND THE RADIO GALAXY 7C 1753+6311
Authors: Cooke E. A. , Hatch N. A. , Stern D. , Rettura A. , Brodwin M. , Galametz A. , Wylezalek D. , Bridge C. , Conselice C. J. , Breuck C. De , Gonzalez A. H. , Jarvis M. 
Published: January 2016

ABSTRACT
We report on the discovery of a z = 1.58 mature cluster around the high-redshift radio galaxy 7C 1753+6311, first identified in the Clusters Around Radio-loud active galactic nuclei survey. Two-thirds of the excess galaxies within the central 1 Mpc lie on a red sequence with a color that is consistent with an average formation redshift of z
f ∼ 3. We show that 80 ± 6% of the red sequence galaxies in the cluster core are quiescent, while the remaining 20% are red due to dusty star formation. We demonstrate that the cluster has an enhanced quiescent galaxy fraction that is three times that of the control field. We also show that this enhancement is mass dependent: 91 ± 9% of the

M
⊙ cluster galaxies are quiescent, compared to only 36 ± 2% of field galaxies, whereas the fraction of quiescent galaxies with lower masses is the same in the cluster and field environments. The presence of a dense core and a well-formed, quiescent red sequence suggest that this is a mature cluster. This means that distant radio galaxies do not solely reside in young, uncollapsed protoclusters, rather they can be found in clusters in a wide range of evolutionary states.
INFRARED COLOR SELECTION OF MASSIVE GALAXIES AT z > 3
Authors: Wang (王涛) T. , Elbaz D. , Schreiber C. , Pannella M. , Shu X. , Willner S. P. , Ashby M. L. N. , Huang J.-S. , Fontana A. , Dekel A. , Daddi E. , Ferguson H. C. , Dunlop J. , Ciesla L. , Koekemoer A. M. , Giavalisco M. , Boutsia K. , Finkelstein S. , Juneau S. , Barro G. , Koo D. C. , Michałowski M. J. , Orellana G. , Lu Y. , Castellano M. , Bourne N. , Buitrago F. , Santini P. , Faber S. M. , Hathi N. , Lucas R. A. , Pérez-González P. G. 
Published: January 2016

ABSTRACT
We introduce a new color selection technique to identify high-redshift, massive galaxies that are systematically missed by Lyman-break selection. The new selection is based on the H
160 (H) and Infrared Array Camera (IRAC) 4.5 μm bands, specifically

mag. These galaxies, called “HIEROs,” include two major populations that can be separated with an additional J − H color. The populations are massive and dusty star-forming galaxies at

(

) and extremely dusty galaxies at

(

). The 350 arcmin2 of the GOODS-North and GOODS-South fields with the deepest Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) near-infrared and IRAC data contain as many as 285 HIEROs down to

mag. Inclusion of the most extreme HIEROs, not even detected in the H band, makes this selection particularly complete for the identification of massive high-redshift galaxies. We focus here primarily on

(

) HIEROs, which have a median photometric redshift

and stellar mass

and are much fainter in the rest-frame UV than similarly massive Lyman-break galaxies (LBGs). Their star formation rates (SFRs), derived from their stacked infrared spectral energy distributions (SEDs), reach ∼240

yr−1, leading to a specific SFR,

Gyr−1, suggesting that the sSFRs for massive galaxies continue to grow at

but at a lower growth rate than from z = 0 to z = 2. With a median half-light radius of 2 kpc, including

as compact as quiescent (QS) galaxies at similar redshifts,

HIEROs represent perfect star-forming progenitors of the most massive (

) compact QS galaxies at

and have the right number density. HIEROs make up

of all galaxies with

identified at

from their photometric redshifts. This is five times more than LBGs with nearly no overlap between the two populations. While HIEROs make up 15%–25% of the total SFR density at

–5, they completely dominate the SFR density taking place in

galaxies, and HIEROs are therefore crucial to understanding the very early phase of massive galaxy formation.
THE CONTRIBUTION OF HOST GALAXIES TO THE INFRARED ENERGY OUTPUT OF z ≳ 5.0 QUASARS
Authors: Lyu(吕建伟) Jianwei , Rieke G. H. , Alberts Stacey 
Published: January 2016

ABSTRACT
The infrared spectral energy distributions of z ≳ 5 quasars can be reproduced by combining a low-metallicity galaxy template with a standard active galactic nucleus (AGN) template. The host galaxy is represented by Haro 11, a compact, moderately low metallicity, starbursting galaxy that shares typical features of high-z galaxies. For the vast majority of z ≳ 5 quasars, the AGN contribution is well modeled by a standard empirical template with the contamination of star formation in the infrared subtracted. Together, these two templates can separate the contributions from the host galaxy and the AGN even in the case of limited data points, given that this model has only two free parameters. Using this method, we reanalyze 69 z ≳ 5 quasars with extensive Herschel observations and derive their AGN luminosities [L
AGN

infrared luminosities from star formation [

and corresponding star formation rates (

). The average infrared luminosity from star formation and the average total AGN luminosity of the z ≳ 5 quasar sample follow the correlation defined by quasars at z < 2.6. We assume that these quasar host galaxies maintain a constant average SFR (∼620 M
⊙ yr−1) during their mass assembly and estimate the stellar mass that could form prior to z ∼ 5−6 to be

Combining with the black hole (BH) mass measurements, this stellar mass is adequate to establish a BH–galaxy mass ratio

at 0.1%–1%, consistent with the local relation.
SIMULTANEOUS IRIS AND HINODE/EIS OBSERVATIONS AND MODELING OF THE 2014 OCTOBER 27 X2.0 CLASS FLARE
Authors: Polito V. , Reep J. W. , Reeves K. K. , Simões P. J. A. , Dudík J. , Del Zanna G. , Mason H. E. , Golub L. 
Published: January 2016

ABSTRACT
We present a study of the X2-class flare which occurred on 2014 October 27 and was observed with the Interface Region Imaging Spectrograph (IRIS) and the EUV Imaging Spectrometer (EIS) on board the Hinode satellite. Thanks to the high cadence and spatial resolution of the IRIS and EIS instruments, we are able to compare simultaneous observations of the Fe xxi 1354.08 Å and Fe xxiii 263.77 Å high-temperature emission (≳10 MK) in the flare ribbon during the chromospheric evaporation phase. We find that IRIS observes completely blueshifted Fe xxi line profiles, up to 200 km s−1 during the rise phase of the flare, indicating that the site of the plasma upflows is resolved by IRIS. In contrast, the Fe xxiii line is often asymmetric, which we interpret as being due to the lower spatial resolution of EIS. Temperature estimates from SDO/AIA and Hinode/XRT show that hot emission (log(T[K]) > 7.2) is first concentrated at the footpoints before filling the loops. Density-sensitive lines from IRIS and EIS give estimates of electron number density of ≳1012 cm−3 in the transition region lines and 1010 cm−3 in the coronal lines during the impulsive phase. In order to compare the observational results against theoretical predictions, we have run a simulation of a flare loop undergoing heating using the HYDRAD 1D hydro code. We find that the simulated plasma parameters are close to the observed values that are obtained with IRIS, Hinode, and AIA. These results support an electron beam heating model rather than a purely thermal conduction model as the driving mechanism for this flare.
BREAKOUT RECONNECTION OBSERVED BY THE TESIS EUV TELESCOPE
Authors: Reva A. A. , Ulyanov A. S. , Shestov S. V. , Kuzin S. V. 
Published: January 2016

ABSTRACT
We present experimental evidence of the coronal mass ejection (CME) breakout reconnection, observed by the TESIS EUV telescope. The telescope could observe solar corona up to 2 R
⊙ from the Sun center in the Fe 171 Å line. Starting from 2009 April 8, TESIS observed an active region (AR) that had a quadrupolar structure with an X-point 0.5 R
⊙ above photosphere. A magnetic field reconstructed from the Michelson Doppler Imager data also has a multipolar structure with an X-point above the AR. At 21:45 UT on April 9, the loops near the X-point started to move away from each other with a velocity of ≈7 km s−1. At 01:15 UT on April 10, a bright stripe appeared between the loops, and the flux in the GOES 0.5–4 Å channel increased. We interpret the loops’ sideways motion and the bright stripe as evidence of the breakout reconnection. At 01:45 UT, the loops below the X-point started to slowly move up. At 15:10 UT, the CME started to accelerate impulsively, while at the same time a flare arcade formed below the CME. After 15:50 UT, the CME moved with constant velocity. The CME evolution precisely followed the breakout model scenario.
TATOOINE NURSERIES: STRUCTURE AND EVOLUTION OF CIRCUMBINARY PROTOPLANETARY DISKS
Authors: Vartanyan David , Garmilla José A. , Rafikov Roman R. 
Published: January 2016

ABSTRACT
Recent discoveries of circumbinary planets by the Kepler mission provide motivation for understanding their birthplaces—protoplanetary disks around stellar binaries with separations

. We explore properties and evolution of such circumbinary disks focusing on modification of their structure caused by tidal coupling to the binary. We develop a set of analytical scaling relations describing viscous evolution of the disk properties, which are verified and calibrated using 1D numerical calculations with realistic inputs. Injection of angular momentum by the central binary suppresses mass accretion onto the binary and causes radial distribution of the viscous angular momentum flux

to be different from that in a standard accretion disk around a single star with no torque at the center. Disks with no mass accretion at the center develop an

profile that is flat in radius. Radial profiles of temperature and surface density are also quite different from those in disks around single stars. Damping of the density waves driven by the binary and viscous dissipation dominates heating of the inner disk (within 1–2 AU), pushing the ice line beyond 3–5 AU, depending on disk mass and age. Irradiation by the binary governs disk thermodynamics beyond ∼10 AU. However, self-shadowing by the hot inner disk may render central illumination irrelevant out to ∼20 AU. Spectral energy distribution of a circumbinary disk exhibits a distinctive bump around 10 μm, which may facilitate identification of such disks around unresolved binaries. Efficient tidal coupling to the disk drives orbital inspiral of the binary and may cause low-mass and relatively compact binaries to merge into a single star within the disk lifetime. We generally find that circumbinary disks present favorable sites for planet formation (despite their wider zone of volatile depletion), in agreement with the statistics of Kepler circumbinary planets.
OGLE ATLAS OF CLASSICAL NOVAE. II. MAGELLANIC CLOUDS
Authors: Mróz P. , Udalski A. , Poleski R. , Soszyński I. , Szymański M. K. , Pietrzyński G. , Wyrzykowski Ł. , Ulaczyk K. , Kozłowski S. , Pietrukowicz P. , Skowron J. 
Published: January 2016

ABSTRACT
The population of classical novae in the Magellanic Clouds was poorly known because of a lack of systematic studies. There were some suggestions that nova rates per unit mass in the Magellanic Clouds were higher than in any other galaxy. Here, we present an analysis of data collected over 16 years by the OGLE survey with the aim of characterizing the nova population in the Clouds. We found 20 eruptions of novae, half of which are new discoveries. We robustly measure nova rates of 2.4 ± 0.8 yr−1 (LMC) and 0.9 ± 0.4 yr−1 (SMC) and confirm that the K-band luminosity-specific nova rates in both Clouds are 2–3 times higher than in other galaxies. This can be explained by the star formation history in the Magellanic Clouds, specifically the re-ignition of the star formation rate a few Gyr ago. We also present the discovery of the intriguing system OGLE-MBR133.25.1160, which mimics recurrent nova eruptions.
Osservazioni sull’architettura templare della Sicilia ellenistica. Per una rilettura dei dati
Authors: Fuduli Leonardo 
Published: January 2016

Les données issues de la recherche archéologique de cette dernière décennie sur l’architecture des temples de la Sicile hellénistique poussent à tenter une nouvelle synthèse sur cette question habituellement négligée. Alors qu’on y voit une période de décadence, en réalité la construction n’a pas cessé après le iv	e s. av. J.‑C. et elle a continué sans interruption, sous des formes particulières. Dans ces temples sont attestés des traits remarqués dans tout le monde grec, comme de nouvelles dimensions pour l’ordre dorique et le déclin des temples périptères, ce dernier trait étant peut‑être à mettre en rapport avec les besoins propres à chaque cité, sachant que beaucoup disposaient déjà d’édifices religieux en fonction depuis les siècles précédents. Mais on connaît peu de choses sur le décor architectural des édifices, alors qu’il ne manque pas d’originalité, comme le montre la moulure appelée kyma hiéronien, qui peut être considérée comme une création locale inspirée de modèles antérieurs. L’identification des cultes pratiqués dans chacun des édifices est débattue, dans l’attente de nouvelles trouvailles qui permettent de trancher.