bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discovery of Strong Balmer Line Absorption in Two Luminous LoBAL Quasars at z ∼ 1.5
Authors: Schulze Andreas , Misawa Toru , Zuo Wenwen , Wu Xue-Bing 
Published: February 2018

Abstract
We present the discovery of strong Balmer line absorption in Hα to Hγ in two luminous low-ionization broad absorption line quasars at

, with black hole masses around

from near-IR spectroscopy. There are only two previously known quasars at

showing Balmer line absorption. SDSS J1019+0225 shows blueshifted absorption by ∼1400 km s−1 with an Hα rest-frame equivalent width of 13 Å. In SDSS J0859+4239, we find redshifted absorption by ∼500 km s−1 with an Hα rest-frame equivalent width of 7 Å. The redshifted absorption could indicate an inflow of high-density gas onto the black hole, though we cannot rule out alternative interpretations. The Balmer line absorption in both objects appears to be saturated, indicating partial coverage of the background source by the absorber. We estimate the covering fractions and optical depth of the absorber and derive neutral hydrogen column densities, N
H i
∼ 1.3 × 1018 cm−2 for SDSS J1019+0225 and N
H i
∼ 9 × 1017 cm−2 for SDSS J0859+4239. In addition, the optical spectra reveal also absorption troughs in He i*

and

in both objects.
A Green Bank Telescope Survey of Large Galactic H ii Regions
Authors: Anderson L. D. , Armentrout W. P. , Luisi Matteo , Bania T. M. , Balser Dana S. , Wenger Trey V. 
Published: February 2018

Abstract
As part of our ongoing H ii Region Discovery Survey (HRDS), we report the Green Bank Telescope detection of 148 new angularly large Galactic H ii regions in radio recombination line (RRL) emission. Our targets are located at a declination of

, which corresponds to

at

. All sources were selected from the Wide-field Infrared Survey Explorer Catalog of Galactic H ii Regions, and have infrared angular diameters

. The Galactic distribution of these “large” H ii regions is similar to that of the previously known sample of Galactic H ii regions. The large H ii region RRL line width and peak line intensity distributions are skewed toward lower values, compared with that of previous HRDS surveys. We discover seven sources with extremely narrow RRLs

. If half the line width is due to turbulence, these seven sources have thermal plasma temperatures

. These temperatures are lower than any measured for Galactic H ii regions, and the narrow-line components may arise instead from partially ionized zones in the H ii region photodissociation regions. We discover G039.515+00.511, one of the most luminous H ii regions in the Galaxy. We also detect the RRL emission from three H ii regions with diameters

, making them some of the physically largest known H ii regions in the Galaxy. This survey completes the HRDS H ii region census in the Northern sky, where we have discovered 887 H ii regions and more than doubled the size of the previously known census of Galactic H ii regions.
Carbon Stars Identified from LAMOST DR4 Using Machine Learning
Authors: Li Yin-Bi , Luo A-Li , Du Chang-De , Zuo Fang , Wang Meng-Xin , Zhao Gang , Jiang Bi-Wei , Zhang Hua-Wei , Liu Chao , Qin Li , Wang Rui , Du Bing , Guo Yan-Xin , Wang Bo , Han Zhan-Wen , Xiang Mao-Sheng , Huang Yang , Chen Bing-Qiu , Chen Jian-Jun , Kong Xiao , Hou Wen , Song Yi-Han , Wang You-Fen , Wu Ke-Fei , Zhang Jian-Nan , Zhang Yong , Wang Yue-Fei , Cao Zi-Huang , Hou Yong-Hui , Zhao Yong-Heng 
Published: February 2018

Abstract
In this work, we present a catalog of 2651 carbon stars from the fourth Data Release (DR4) of the Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST). Using an efficient machine-learning algorithm, we find these stars from more than 7 million spectra. As a by-product, 17 carbon-enhanced metal-poor turnoff star candidates are also reported in this paper, and they are preliminarily identified by their atmospheric parameters. Except for 176 stars that could not be given spectral types, we classify the other 2475 carbon stars into five subtypes: 864 C-H, 226 C-R, 400 C-J, 266 C-N, and 719 barium stars based on a series of spectral features. Furthermore, we divide the C-J stars into three subtypes, C-J(H), C-J(R), and C-J(N), and about 90% of them are cool N-type stars as expected from previous literature. Besides spectroscopic classification, we also match these carbon stars to multiple broadband photometries. Using ultraviolet photometry data, we find that 25 carbon stars have FUV detections and that they are likely to be in binary systems with compact white dwarf companions.
Eleven remarkable Diptera species, emerged from fallen aspens in Kivach Nature Reserve, Russian Karelia
Authors: Polevoi Alexei , Ruokolainen Anna , Shorohova Ekaterina 
Published: February 2018

In 2016, saproxylic Diptera associated with aspen (Populus tremula L.) logs were studied in the Kivach Nature Reserve, Russian Karelia, using trunk emergence traps.
Eleven rare species of Diptera (families Limoniidae, Scatopsidae, Axymyiidae, Mycetophilidae, Sciaridae, Platypezidae, Syrphidae and Clusiidae) with poorly known distribution and ecology were recorded. For each species, basic diagnostic characteristics were provided along with the information on microhabitats. An attempt was also undertaken to outline possible associations with wood-decaying macrofungi using nonparametric correlation.
Fight against discrimination or promotion of diversity in employment? A public policy in the Brussels-Capital Region (1997-2012)
Authors: Tandé Alexandre 
Published: February 2018

At the end of the 1990s, the Brussels-Capital Region launched actions to fight against employment discrimination with respect to people of foreign origin. In a social and historical perspective, using oral and documentary sources, this article presents the context in which this public policy emerged, the experimental actions in the first years, and its transformation in the mid 2000s. At the same time that it was consolidated (inclusion of new measures in the regional law, establishment of a Brussels unit of consultants in the area of diversity), this policy was also given a new objective: the promotion of diversity. While the fight against discrimination and the promotion of diversity are often presented as the "two sides of the same coin", these two objectives may also diverge or oppose each other. A review of the history of this Brussels policy, its evolution and impact, therefore allows the current responses to two major challenges for the urban area to be questioned: the inequality of access to employment and the recognition of sociocultural diversity.
El smartphone como barómetro en experimentos de Física
Authors: Salilnas Isabel , Giménez Marcos H. , Monsoriu Juan A. , Castro Palacio Juan Carlos 
Published: February 2018

<p>En este trabajo se presentan dos experimentos que sacan partido del sensor de presión de los teléfonos inteligentes, utilizándolo para determinar su valor en el seno de agua en equilibrio en una probeta. En un primer experimento, destinado a estudiantes de Secundaria y niveles superiores, las medidas de la presión obtenidos a diferentes profundidades permiten realizar un ajuste lineal, comprobando así la validez de la Ley de Stevin. Además, a partir de dicha ley y de los parámetros del ajuste se puede determinar la densidad del agua. Los valores obtenidos indirectamente por este procedimiento difieren entre un 2% y un 4% del resultado de dividir entre sí la masa y el volumen de una muestra. En un segundo experimento, más enfocado a estudiantes de primeros cursos universitarios de asignaturas de Física, el teléfono móvil sumergido oscila suspendido de un muelle. Las medidas del sensor de presión permiten, mediante la Ley de Stevin, obtener la serie temporal de la presión en la correspondiente oscilación amortiguada, cuyos parámetros se determinan mediante un ajuste no lineal. La comparación de la pulsación libre obtenida a partir de estos valores difiere en un1,5% respecto del obtenido a partir de la medición directa del periodo fuera del agua. En ambos casos, los resultados obtenidos indican la efectividad del método utilizado en contextos docentes.</p>
Initiation of secondary ice production in clouds
Authors: Sullivan Sylvia C. , Hoose Corinna , Kiselev Alexei , Leisner Thomas , Nenes Athanasios 
Published: February 2018

Abstract. Disparities between the measured concentrations of ice-nucleating particles (INPs) and in-cloud ice crystal number
concentrations (ICNCs) have led to the hypothesis that mechanisms other than primary nucleation form ice in the
atmosphere. Here, we model three of these secondary production mechanisms – rime splintering, frozen droplet shattering,
and ice–ice collisional breakup – with a six-hydrometeor-class parcel model. We perform three sets of simulations to
understand temporal evolution of ice hydrometeor number (Nice), thermodynamic limitations, and the impact of
parametric uncertainty when secondary production is active. Output is assessed in terms of the number of primarily
nucleated ice crystals that must exist before secondary production initiates (NINP(lim)) as well as
the ICNC enhancement from secondary production and the timing of a 100-fold enhancement. Nice evolution can be
understood in terms of collision-based nonlinearity and the “phasedness” of the process, i.e., whether it involves ice
hydrometeors, liquid ones, or both. Ice–ice collisional breakup is the only process for which a meaningful
NINP(lim) exists (0.002 up to 0.15 L−1). For droplet shattering and rime splintering,
a warm enough cloud base temperature and modest updraft are the more important criteria for initiation. The low values of
NINP(lim) here suggest that, under appropriate thermodynamic conditions for secondary ice
production, perturbations in cloud concentration nuclei concentrations are more influential in mixed-phase partitioning than those in INP
concentrations.
Peat decomposability in managed organic soils in relation to land use, organic matter composition and temperature
Authors: Bader Cédric , Müller Moritz , Schulin Rainer , Leifeld Jens 
Published: February 2018

Abstract. Organic soils comprise a large yet fragile carbon (C) store in the global C cycle. Drainage, necessary for agriculture and forestry, triggers rapid decomposition of soil organic matter (SOM), typically increasing in the order forest < grassland < cropland. However, there is also large variation in decomposition due to differences in hydrological conditions, climate and specific management. Here we studied the role of SOM composition on peat decomposability in a variety of differently managed drained organic soils. We collected a total of 560 samples from 21 organic cropland, grassland and forest soils in Switzerland, monitored their CO2 emission rates in lab incubation experiments over 6 months at two temperatures (10 and 20 °C) and related them to various soil characteristics, including bulk density, pH, soil organic carbon (SOC) content and elemental ratios (C / N, H / C and O / C). CO2 release ranged from 6 to 195 mg CO2-C g−1 SOC at 10 °C and from 12 to 423 mg g−1 at 20 °C. This variation occurring under controlled conditions suggests that besides soil water regime, weather and management, SOM composition may be an underestimated factor that determines CO2 fluxes measured in field experiments. However, correlations between the investigated chemical SOM characteristics and CO2 emissions were weak. The latter also did not show a dependence on land-use type, although peat under forest was decomposed the least. High CO2 emissions in some topsoils were probably related to the accrual of labile crop residues. A comparison with published CO2 rates from incubated mineral soils indicated no difference in SOM decomposability between these soil classes, suggesting that accumulation of recent, labile plant materials that presumably account for most of the evolved CO2 is not systematically different between mineral and organic soils. In our data set, temperature sensitivity of decomposition (Q10 on average 2.57 ± 0.05) was the same for all land uses but lowest below 60 cm in croplands and grasslands. This, in turn, indicates a relative accumulation of recalcitrant peat in topsoils.
Tracking the direct impact of rainfall on groundwater at Mt. Fuji by multiple analyses including microbial DNA
Authors: Sugiyama Ayumi , Masuda Suguru , Nagaosa Kazuyo , Tsujimura Maki , Kato Kenji 
Published: February 2018

Abstract. A total of 2 to 3 million tons of spring water flushes out from the foot of Mt. Fuji, the largest volcanic mountain in Japan. Based on the concept of piston flow transport, residence time of stored groundwater at Mt. Fuji was estimated at  ∼  15–30 years by the 36Cl ∕ Cl ratio (Tosaki et al., 2011). This range, however, represents the average residence time of groundwater that was mixed before it flushed out. To elucidate the route of groundwater in a given system, we determined signatures of direct impacts of rainfall on groundwater, using microbial, stable isotopic (δ18O), and chemical analyses (concentration of silica). Chemical analysis of the groundwater gave an average value of the water, which was already mixed with waters from various sources and routes in the subsurface environment. The microbial analysis suggested locations of water origin and paths. In situ observation during four rainfall events revealed that the stable oxygen isotopic signature obtained from spring water (at 726 m a.s.l., site SP-0 m) and shallow groundwater (at 150 m a.s.l., site GW-42 m), where the average recharge height from rainfall was 1700–1800 m, became greater than values observed prior to a torrential rain producing more than 300 mm of precipitation. The concentration of silica decreased after this event. In addition, the abundance of Bacteria in spring water increased, suggesting the influence of heavy rain. Such changes did not appear when rainfall was less than 100 mm per event. The above findings indicate a rapid flow of rain through the shallow part of the aquifer, which appeared within a few weeks of torrential rain extracting abundant microbes from soil in the studied geologic setting. Interestingly, we found that after the torrential rain, the abundance of Archaea increased in the deep groundwater at site GW-550 m,  ∼  12 km downstream of SP-0 m. However, chemical parameters did not show any change after the event. This suggests that strengthened piston flow caused by the heavy rain transported archaeal particles from the geologic layer along the groundwater route. This finding was supported by changes in constituents of Archaea, dominated by Halobacteriales and Methanobacteriales, which were not seen from other observations. Those two groups of Archaea are believed to be relatively tightly embedded in the geologic layer and were extracted from the environment to the examined groundwater through enforced piston flow. Microbial DNA can thus give information about the groundwater route, which may not be shown by analysis of chemical materials dissolved in the groundwater.
Mineralogical and Geochemical Discrimination of the Occurrence and Genesis of Palygorskite in Eocene Sediments on the Northeastern Tibetan Plateau
Authors: Ye Chengcheng , Yang Yibo , Fang Xiaomin , Hong Hanlie , Zhang Weilin , Yang Rongsheng , Song Bowen , Zhang Zhiguo 
Published: February 2018

AbstractPalygorskite is a widely used indicator of semiarid to arid environments in paleoclimate studies. In this study, we present detailed mineralogical and geochemical investigations exploring the genesis of palygorskite found in Eocene fluvial sediment in the northern Qaidam Basin on the northeastern Tibetan Plateau. The presence of two types of palygorskite is revealed, based on their crystallinity characteristics and distinctive rare earth element (REE) patterns in the coexisting clay fraction. Well‐crystallized palygorskite samples are characterized by remarkably negative Ce anomalies and obvious middle rare earth element enrichment. Poorly crystallized palygorskite samples generally exhibit positive Ce anomalies and less pronounced middle rare earth element enrichment, which resemble those of nonpalygorskite‐bearing clay samples. Given the presence of an overall oxidized fluvial sedimentary environment, we attribute the well‐crystallized palygorskite (which has textures comprising long, interwoven fibers) to direct precipitation (i.e., neoformation) occurring within a reducing environment during early/postdepositional processes while the poorly crystallized palygorskite (which is characterized by short, club‐shaped single crystals) originates as catchment‐delivered detritus. These poorly crystallized palygorskites occur mostly in 49.5–47.0 Ma and are accompanied by decreasing kaolinite content, increasing chlorite content, and abundant xerophytic spore‐pollen from the Qaidam Basin, and its neighboring Xining Basin. Collectively, these evidences suggest that a less humid climate followed after the Early Eocene Climate Optimum.
High Pressure Phase Relations of a Depleted Peridotite Fluxed by CO2‐H2O‐Bearing Siliceous Melts and the Origin of Mid‐Lithospheric Discontinuity
Authors: Saha Sriparna , Dasgupta Rajdeep , Tsuno Kyusei 
Published: February 2018

AbstractWe present phase equilibria experiments on a depleted peridotite (Mg# 92) fluxed with variable proportions of a slab‐derived rhyolitic melt (with 9.4 wt.% H2O, 5 wt.% CO2), envisaging an interaction that could occur during formation of continents by imbrication of slabs/accretion of subarc mantles. Experiments were performed with 5 wt.% (Bulk 2) and 10 wt.% (Bulk 1) melt at 950–1175°C and 2–4 GPa using a piston‐cylinder and a multi‐anvil apparatus, to test the hypothesis that volatile‐bearing mineral‐phases produced during craton formation can cause reduction in aggregate shear‐wave velocities (VS) at mid‐lithospheric depths beneath continents. In addition to the presence of olivine, orthopyroxene, clinopyroxene, and garnet/spinel, phlogopite (Bulk 1: 3–7.6 wt.%; Bulk 2: 2.6–5 wt.%) at 2–4 GPa, and amphibole (Bulk 1: 3–9 wt.%; Bulk 2: 2–6 wt.%) at 2–3 GPa (≤1050°C) are also present. Magnesite (Bulk 1: ∼1 wt.% and Bulk 2: ∼0.6 wt.%) is present at 2–4 GPa (<1000°C at 3 and < 1050°C at 4 GPa) and its thermal breakdown coincides with the visual appearance of trace‐melt. However, an extremely small fraction of melt is inferred at all experiments based on the knowledge of fluid‐saturated peridotite solidus and the difference between bulk H2O and total H2O stored in the hydrous phases. Calculated mineral end‐member volume‐proportions were used to calculate VS of the resulting assemblage at experimental conditions and along representative continental geotherms (surface heat flow of 40–50 mWm−2). We note that reactive crystallization of phlogopite ± amphibole by infiltration of 3–10% slab‐derived hydrous‐silicic melt can cause up to 6% reduction in VS and that the estimated reduction in VS increases with increasing melt:rock ratio. The presence of phlogopite limits amphibole‐stability, making phlogopite a more likely candidate for MLDs at >100 km depth.
Polarization Characteristics Inferred From the Radio Receiver Instrument on the Enhanced Polar Outflow Probe
Authors: Danskin Donald W. , Hussey Glenn C. , Gillies Robert G. , James H. Gordon , Fairbairn David T. , Yau Andrew W. 
Published: February 2018

AbstractThe Radio Receiver Instrument (RRI) on the CAScade, Smallsat, and Ionospheric Polar Explorer/enhanced Polar Outflow Probe (CASSIOPE/e‐POP) satellite was used to receive continuous wave and binary phase shift keyed transmissions from a high‐frequency transmitter located in Ottawa, ON, Canada during April 2016 to investigate how the ionosphere affects the polarization characteristics of transionospheric high‐frequency radio waves. The spacecraft orientation was continuously slewed to maintain the dipole orientation in a plane perpendicular to the direction toward the transmitter, enabling the first in situ planar polarization determination for continuous wave and binary phase shift keyed modulated radio waves from space at times when the wave frequency is at least 1.58 times the plasma frequency. The Stokes parameters and polarization characteristics were derived from the measured data and interpreted using an existing ray tracing model. For the southern part of the passes, the power was observed to oscillate between the two dipoles of RRI, which was attributed to Faraday rotation of the radio waves. For the first time, a reversal in the rate of change of orientation angle was observed where the minimum in modeled Faraday rotation occurred. The reversal point was poleward of the point of closest approach between the satellite and transmitter; this was explained by the variations of total electron content and component of magnetic field along the direction of propagation. The received signals show both quasi‐longitudinal (QL) and quasi‐transverse characteristics. South of the transmitter the QL regime is dominant. Around the reversal point, a combination of QL and quasi‐transverse nature was observed.
Reconstruction of Local Sea Levels at South West Pacific Islands—A Multiple Linear Regression Approach (1988–2014)
Authors: Kumar V. , Melet A. , Meyssignac B. , Ganachaud A. , Kessler W. S. , Singh A. , Aucan J. 
Published: February 2018

AbstractRising sea levels are a critical concern in small island nations. The problem is especially serious in the western south Pacific, where the total sea level rise over the last 60 years has been up to 3 times the global average. In this study, we aim at reconstructing sea levels at selected sites in the region (Suva, Lautoka—Fiji, and Nouméa—New Caledonia) as a multilinear regression (MLR) of atmospheric and oceanic variables. We focus on sea level variability at interannual‐to‐interdecadal time scales, and trend over the 1988–2014 period. Local sea levels are first expressed as a sum of steric and mass changes. Then a dynamical approach is used based on wind stress curl as a proxy for the thermosteric component, as wind stress curl anomalies can modulate the thermocline depth and resultant sea levels via Rossby wave propagation. Statistically significant predictors among wind stress curl, halosteric sea level, zonal/meridional wind stress components, and sea surface temperature are used to construct a MLR model simulating local sea levels. Although we are focusing on the local scale, the global mean sea level needs to be adjusted for. Our reconstructions provide insights on key drivers of sea level variability at the selected sites, showing that while local dynamics and the global signal modulate sea level to a given extent, most of the variance is driven by regional factors. On average, the MLR model is able to reproduce 82% of the variance in island sea level, and could be used to derive local sea level projections via downscaling of climate models.