bluuebunny/crossref_metadata_2025_split huggingface dataset:
Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. II The Second Year (2009–2010)
Authors: Kato Taichi , Maehara Hiroyuki , Uemura Makoto , Henden Arne , De Miguel Enrique , Miller Ian , Dubovsky Pavol A. , Kudzej Igor , Kiyota Seiichiro , Hambsch Franz-Josef , Tanabe Kenji , Imamura Kazuyoshi , Kunitomi Nanae , Takagi Ryosuke , Nose Mikiha , Akazawa Hidehiko , Masi Gianluca , Nakagawa Shinichi , Iino Eriko , Noguchi Ryo , Matsumoto Katsura , Fujii Daichi , Kobayashi Hiroshi , Ogura Kazuyuki , Ohtomo Sachi , Yamashita Kousei , Yanagisawa Hirofumi , Itoh Hiroshi , Bolt Greg , Monard Berto , Ohshima Tomohito , Shears Jeremy , Ruiz Javier , Imada Akira , Oksanen Arto , Nelson Peter , Gomez Tomas L. , Staels Bart , Boyd David , Voloshina Irina B. , Krajci Thomas , Crawford Tim , Stockdale Chris , Richmond Michael , Morelle Etienne , NovÁk Rudolf , Nogami Daisaku , Ishioka Ryoko , Brady Steve , Simonsen Mike , Pavlenko Elena P. , Ringwald Frederick A. , Kuramoto Tetsuya , Miyashita Atsushi , Pickard Roger D. , Hynek Tomáš , Dvorak Shawn , Stubbings Rod , Muyllaert Eddy 
Published: February 2014

Abstract
Continued from Kato et al. (2009, PASJ, 61, S395), we collected the times of superhump maxima for 68 SU UMa-type dwarf novae, mainly observed during the 2009–2010 season. The newly obtained data confirmed the basic findings reported in Kato et al. (ibid.): the presence of stages A–C and the predominance of positive period derivatives during stage B in systems with superhump periods shorter than 0.07 d. There was a systematic difference in the period derivatives for the systems with superhump periods longer than 0.075 d between this study and Kato et al. (ibid.). We suggest that this difference was possibly caused by a relative lack of frequently outbursting SU UMa-type dwarf novae in this period regime in the present study. We recorded a strong beat phenomenon during the 2009 superoutburst of IY UMa. A close correlation between the beat period and the superhump period suggests that the changing angular velocity of the apsidal motion of the elliptical disk is responsible for the variation of the superhump periods. We also described three new WZ Sge-type objects with established early superhumps and one with likely early superhumps. We suggest that two systems, VX For and EL UMa, are WZ Sge-type dwarf novae with multiple rebrightenings. The $O-C$ variation in OT J213806.6$+$261957 suggests that the frequent absence of rebrightenings in very short-$P_{\rm orb}$ objects can be the result of a sustained superoutburst plateau at the epoch when usual SU UMa-type dwarf novae return to quiescence, preceding a rebrightening. We also present a formulation for a variety of Bayesian extensions to traditional period analyses.
MOIRCS Deep Survey. X. Evolution of Quiescent Galaxies as a Function of Stellar Mass at 0.5 z 2.5
Authors: Kajisawa Masaru , Ichikawa Takashi , Yoshikawa Tomohiro , Yamada Toru , Onodera Masato , Akiyama Masayuki , Tanaka Ichi 
Published: February 2014

Abstract
We studied the evolution of quiescent galaxies at 0.5 $\lt$z$\lt$ 2.5 as a function of the stellar mass, using very deep NIR imaging data from the MOIRCS Deep Survey in the GOODS-North region. The deep NIR data allowed us to construct a stellar mass-limited sample of quiescent galaxies down to $\sim\ $10$^{10}\ M_{\odot}$, even at z$\sim\ $ 2, for the first time. We selected quiescent galaxies with age / $\tau$$\gt$ 6 by performing a SED fitting of the multi broad-band photometry from the $U$ to Spitzer 5.8$\ \mu$m bands with the population synthesis model of Bruzual and Charlot (2003, MNRAS, 344, 1000), where exponentially decaying star-formation histories are assumed. The number density of quiescent galaxies increases by a factor of $\sim\ $3 from 1.0 $\lt$z$\lt$ 1.5 to 0.5 $\lt$z$\lt$ 1.0, and by a factor of $\sim\ $10 from 1.5 $\lt$z$\lt$ 2.5 to 0.5 $\lt$z$\lt$ 1.0, while that of star-forming galaxies with age / $\tau$$\lt$ 4 increases only by factors of $\sim\ $2 and $\sim\ $3 in the same redshift ranges. At 0.5 $\lt$z$\lt$ 2.5, the low-mass slope of the stellar mass function of quiescent galaxies is $\alpha$$\sim\ $ 0–0.6, which is significantly flatter than those of star-forming galaxies ($\alpha$$\sim\ $$-$1.3–$-$1.5). As a result, the fraction of quiescent galaxies in the overall galaxy population increases with stellar mass in the redshift range. The fraction of quiescent galaxies at 10$^{11}$–10$^{11.5}\ M_{\odot}$ increases from $\sim\ $20%–30% at z$\sim\ $ 2 to $\sim\ $40%–60% at z$\sim\ $ 0.75, while that at 10$^{10}$–10$^{10.5}\ M_{\odot}$ increases from $\lesssim\ $5% to $\sim\ $15% in the same redshift range. These results could suggest that the quenching of star formation had been more effective in more massive galaxies at 1 $\lesssim\ $z$\lesssim\ $ 2. Such a mass-dependent quenching could explain the rapid increase in the number density of $\sim\ M^*$ galaxies relative to lower-mass galaxies at z$\gtrsim$ 1–1.5.
Early Science Result from the Japanese Virtual Observatory: AGN and Galaxy Clustering at z = 0.3 to 3.0
Authors: Shirasaki Yuji , Tanaka Masahiro , Ohishi Masatoshi , Mizumoto Yoshihiko , Yasuda Naoki , Takata Tadafumi 
Published: February 2014

Abstract
We present the result of a projected cross-correlation analysis of AGNs and galaxies at redshifts from 0.3 to 3.0. The Japanese Virtual Observatory (JVO) was used to obtain Subaru Suprime-Cam images and UKIDSS catalog data around AGNs. We investigated 1809 AGNs, which is about a ten-times larger sample than that used in previous studies on AGN–galaxy clustering at redshifts larger than 0.6; 90% of the AGN samples were optically-selected AGN from the SDSS and 2dF catalogs. The galaxy samples at low redshift include many redder objects from the UKIDSS survey, while at higher redshift they are mainly blue galaxies from Suprime-Cam. We found a significant excess of galaxies around the AGNs at redshifts from 0.3 to 1.8. For the low-redshift samples (z$\lt$ 0.9), we obtained a correlation length of $r_{0}$$=$ 5–6$\ h^{-1}$ Mpc ($\gamma$$=$ 1.8), which indicates that the AGNs at this redshift range reside in a similar environment around typical local galaxies. We also found that AGNs at higher redshift ranges reside in a denser environment than lower redshift AGNs. For z$=$ 1.3–1.8 AGNs, the cross-correlation length was measured as 11$^{+6}_{-3}\ h^{-1}$ Mpc ($\gamma$$=$ 1.8). Considering that our sample of galaxies is based on optical observations with Suprime-Cam at the redshift range, it is expected that blue star-forming galaxies comprise the majority of objects that are observed to be clustered around the AGNs. It has been successfully demonstrated that using the archive through the Virtual Observatory system can provide a powerful tool for investigating the small-scale environment of intermediate redshift AGNs.
Enrichment of Heavy Elements in the Red Giant S 15–19 in the Sextans Dwarf Spheroidal Galaxy
Authors: Honda Satoshi , Aoki Wako , Arimoto Nobuo , Sadakane Kozo 
Published: February 2014

Abstract
We determined the chemical abundances of the extremely metal-poor (EMP) star S 15–19 ([Fe$/$H] $=$$-$3.0) in the Sextans dwarf galaxy. While heavy neutron-capture elements (e.g., Ba) are generally deficient in EMP stars in dwarf galaxies, this object was shown to have an exceptional over-abundance of Ba ([Ba$/$Fe] $\sim$$+$0.5) by a previous study, which is similar to those of r-process-enhanced stars found in the field halo. Our new high-resolution spectroscopy for this object for the blue region, however, reveals that no clear excess of r-process elements, like Eu, appears in this object. Moreover, a significant excess of carbon ([C$/$Fe] $=$$+$1.0) and a deficiency of Sr ([Sr$/$Fe] $=$$-$1.4) are found for this object. Taking the variation of the radial velocities measured at the two different epochs into consideration, the origin of the excesses of heavy neutron-capture elements in S 15–19 is not the r-process, but is the s-process in an asymptotic giant branch (AGB) star that was the binary companion (primary) of this object. Carbon- and s-process-enhanced material should have been transferred to the surface of S 15–19 across the binary system. These results are compared with carbon-enhanced metal-poor stars in the field halo.
Chromospheres in Metal-Poor Stars Evidenced from the He I 10830 Å Line
Authors: Takeda Yoichi , Takada-Hidai Masahide 
Published: February 2014

Abstract
Based on the near-IR spectra of 33 late-type stars in a wide metallicity range (mainly dwarfs and partly giants) obtained with IRCS$+$AO188 of the Subaru Telescope, we confirmed that the He I 10830 Å line is seen in absorption in almost all moderately to extremely metal-poor stars of thick disk and halo population (from [Fe$/$H] $\sim$ $-$0.5 down to [Fe$/$H] $\sim$ $-$3.7), the strength of which is almost constant irrespective of the metallicity. This is evidence that chromospheric activity at a basal level persists, even for such old stars, despite that their rotations are considered to be slowed down and incapable of sustaining a dynamo, suggesting that some kind of chromospheric heating mechanism independent of rotation/magnetism (e.g., acoustic heating) may take place.
Subaru Lightcurve Observations of Sub-km-Sized Main-Belt Asteroids
Authors: Dermawan Budi , Nakamura Tsuko , Yoshida Fumi 
Published: February 2014

Abstract
The currently known spin period vs size distribution of asteroids includes a very small number of sub-km-sized main-belt asteroids (MBAs). In order to get a better understanding of such objects, we conducted lightcurve observations using the wide-field camera (Suprime-Cam) of the 8.2 m Subaru telescope in 2001 October. We surveyed a sky field of 34$'$$\times$ 27$'$ near opposition and the ecliptic, covering a time-span of 8.3 hr for a single night, and detected 127 asteroids down to a limiting magnitude of $R$$\approx$ 24.6 mag (at a level of 90% fractional detection). Since the majority of our lightcurves consisted of data points of only a few tens, we took an approach with an emphasis on searching for a dominant period of a lightcurve using two independent periodogram codes, to ascertain the mutual consistency of the obtained results. In an attempt to estimate their period errors, we made extensive simulations using artificial lightcurve data, and found that most errors do not exceed $\sim$ 0.1 hr; this level of errors is sufficiently small for the purposes of this survey observation. Out of 68 main-belt asteroids showing reliable spin periods, 33 are found to be fast-rotator MBAs, whose spin periods range from 0.5 to 2.2 hr (hereafter asteroids with periods $\lt$ 2.2 hr are abbreviated as FRAs). This result is the first observational confirmation on the existence of FRAs among sub-km MBAs; those detected small MBAs fill up the region that used to be almost void of asteroids in the spin period vs size distribution. Regarding the shapes of those objects, which were inferred from their lightcurve amplitudes, we found a tendency that FRAs are more spherical than non-FRAs. Cumulative size distributions of the FRAs and non FRAs are also compared, but revealing no clear difference.
First On-Site Data Analysis System for Subaru/Suprime-Cam
Authors: Furusawa Hisanori , Okura Yuki , Mineo Sogo , Takata Tadafumi , Nakata Fumiaki , Tanaka Manobu , Katayama Nobuhiko , Itoh Ryosuke , Yasuda Naoki , Miyazaki Satoshi , Komiyama Yutaka , Utsumi Yousuke , Uchida Tomohisa , Aihara Hiroaki 
Published: February 2014

Abstract
We developed an automated on-site quick analysis system for mosaic CCD data of Suprime-Cam, which is a wide-field camera mounted at the prime focus of the Subaru Telescope, Mauna Kea, Hawaii. The first version of the data-analysis system was constructed, and started to operate in general observations. This system is a new function of observing support at the Subaru Telescope to provide the Subaru user community with an automated on-site data evaluation, aiming at improvements of observers' productivity, especially in large imaging surveys. The new system assists the data evaluation tasks in observations by the continuous monitoring of the characteristics of every data frame during observations. The evaluation results and data frames processed by this system are also useful for reducing the data-processing time in a full analysis after an observation. The primary analysis functions implemented in the data-analysis system are composed of automated realtime analysis for data evaluation and on-demand analysis, which is executed upon request, including mosaicing analysis and flat making analysis. In data evaluation, which is controlled by the organizing software, the database keeps track of the analysis histories, as well as the evaluated values of data frames, including seeing and sky background levels; it also helps in the selection of frames for mosaicing and flat making analysis. We examined the system performance and confirmed an improvement in the data-processing time by a factor of 9 with the aid of distributed parallel data processing and on-memory data processing, which makes the automated data evaluation effective.
Suzaku studies of luminosity-dependent changes in the low-mass X-ray binary Aquila X-1
Authors: Sakurai Soki , Torii Shunsuke , Noda Hirofumi , Zhang Zhongli , Ono Ko , Nakazawa Kazuhiro , Makishima Kazuo , Takahashi Hiromitsu , Yamada Shin'ya , Matsuoka Masaru 
Published: February 2014

Abstract
The neutron-star low-mass X-ray binary Aquila X-1 was observed by Suzaku seven times, from 2007 September 28 to October 30. The observations successfully traced an outburst decay in which the source luminosity decreased almost monotonically from ∼ 1037 erg s−1 to ∼ 1034 erg s−1, by ∼ 3 orders of magnitude. To investigate luminosity-dependent changes in the accretion geometry, five of the seven data sets with a typical exposure of ∼ 18 ks each were analyzed; the other two were utilized in a previous work (Sakurai et al. 2012, PASJ, 64, 72). The source was detected up to 100 keV in the second to the fourth observations, to 40 keV in the fifth, and to 10 keV on the last two occasions. All spectra were reproduced successfully by a Comptonized blackbody model with relatively high (≳ 2.0) optical depths, plus an additional softer optically-thick component. The faintest three spectra were reproduced alternatively by a single Comptonized blackbody model with a relatively low (≲ 0.8) optical depth. The estimated radius of the blackbody emission, including seed photons for the Comptonization, was 10 ± 2 km at a 0.8–100 keV luminosity of 2.4 × 1036 erg s−1 (the second to the fourth observations). In contrast, it decreased to 7 ± 1 km and further to 3 ± 1 km, at a luminosity of (4.8−5.2) × 1035 erg s−1 (the fifth observation) and ∼ 2 × 1034 erg s−1 (the sixth and seventh), respectively, regardless of the above model ambiguity. This can be taken as evidence for the emergence of a weak magnetosphere from the neutron star.
The AKARI Far-Infrared Surveyor young stellar object catalog
Authors: Tóth L. Viktor , Marton Gábor , Zahorecz Sarolta , Balázs Lajos G. , Ueno Munetaka , Tamura Motohide , Kawamura Akiko , Kiss Zoltán T. , Kitamura Yoshimi 
Published: February 2014

Abstract
We demonstrate the use of the AKARI all-sky survey photometric data in the study of galactic star formation. Our aim was to select young stellar objects (YSOs) in the AKARI Far-Infrared Surveyor (FIS) Bright Source Catalogue. We used AKARI/FIS and Wide-field Infrared Survey Explorer (WISE) data to derive mid- and far-infrared colors of YSOs. Classification schemes based on quadratic discriminant analysis (QDA) have been given for YSOs and the training catalog for QDA was the whole-sky selection of previously known YSOs (i.e., listed in the SIMBAD database). A new catalog of AKARI FIS YSO candidates including 44001 sources has been prepared; the reliability of the classification is over 90%, as tested in comparison to known YSOs. As much as 76% of our YSO candidates are from previously uncatalogued types. The vast majority of these sources are Class I and II types according to the Lada classification. The distribution of AKARI FIS YSOs is well correlated with that of the galactic ISM; local over-densities were found on infrared loops and towards the cold clumps detected by Planck.
The environment around the young massive star cluster RSGC 1 and HESS J1837−069
Authors: Fujita Yutaka , Nakanishi Hiroyuki , Muller Erik , Kobayashi Naoto , Saito Masao , Yasui Chikako , Kikuchi Hiroki , Yoshinaga Keigo 
Published: February 2014

Abstract
We report on Mopra observations of the young massive star cluster RSGC 1, adjoined to and possibly associated with the gamma-ray source HESS J1837−069. We measure the CO (J = 1–0) distribution around the cluster and gamma-ray source, and find that the cluster is slightly higher than the velocity ranges associated with the Crux–Scutum arm. We reveal that the cluster is associated with much less molecular gas compared with other young massive clusters in the Galaxy, Westerlund 1 (Wd 1) and 2 (Wd 2), which also radiate gamma-rays. We find no other structures that would otherwise indicate the action of supernova remnants, and due to the lack of material which may form gamma-rays by hadronic interaction, we conclude that the gamma-rays detected from HESS J1837−069 are not created through proton–proton interactions, and may more plausibly originate from the pulsar that was recently found near RSGC 1.
Evolution of Gene Structural Complexity: An Alternative-Splicing-Based Model Accounts for Intron-Containing Retrogenes
Authors: Zhang Chengjun , Gschwend Andrea R. , Ouyang Yidan , Long Manyuan 
Published: February 2014

AbstractThe structure of eukaryotic genes evolves extensively by intron loss or gain. Previous studies have revealed two models for gene structure evolution through the loss of introns: RNA-based gene conversion, dubbed the Fink model and retroposition model. However, retrogenes that experienced both intron loss and intron-retaining events have been ignored; evolutionary processes responsible for the variation in complex exon-intron structure were unknown. We detected hundreds of retroduplication-derived genes in human (Homo sapiens), fly (Drosophila melanogaster), rice (Oryza sativa), and Arabidopsis (Arabidopsis thaliana) and categorized them either as duplicated genes that have all introns lost or as duplicated genes that have at least lost one and retained one intron compared with the parental copy (intron-retaining [IR] type). Our new model attributes intron retention alternative splicing to the generation of these IR-type gene pairs. We presented 25 parental genes that have an intron retention isoform and have retained introns in the same locations in the IR-type duplicate genes, which directly support our hypothesis. Our alternative-splicing-based model in conjunction with the retroposition and Fink models can explain the IR-type gene observed. We discovered a greater percentage of IR-type genes in plants than in animals, which may be due to the abundance of intron retention cases in plants. Given the prevalence of intron retention in plants, this new model gives a support that plant genomes have very complex gene structures.
The BAF60 Subunit of the SWI/SNF Chromatin-Remodeling Complex Directly Controls the Formation of a Gene Loop at FLOWERING LOCUS C in Arabidopsis
Authors: Jégu Teddy , Latrasse David , Delarue Marianne , Hirt Heribert , Domenichini Séverine , Ariel Federico , Crespi Martin , Bergounioux Catherine , Raynaud Cécile , Benhamed Moussa 
Published: February 2014

Abstract
SWI/SNF complexes mediate ATP-dependent chromatin remodeling to regulate gene expression. Many components of these complexes are evolutionarily conserved, and several subunits of Arabidopsis thaliana SWI/SNF complexes are involved in the control of flowering, a process that depends on the floral repressor FLOWERING LOCUS C (FLC). BAF60 is a SWI/SNF subunit, and in this work, we show that BAF60, via a direct targeting of the floral repressor FLC, induces a change at the high-order chromatin level and represses the photoperiod flowering pathway in Arabidopsis. BAF60 accumulates in the nucleus and controls the formation of the FLC gene loop by modulation of histone density, composition, and posttranslational modification. Physiological analysis of BAF60 RNA interference mutant lines allowed us to propose that this chromatin-remodeling protein creates a repressive chromatin configuration at the FLC locus.
ArabidopsisDAYU/ABERRANT PEROXISOME MORPHOLOGY9 Is a Key Regulator of Peroxisome Biogenesis and Plays Critical Roles during Pollen Maturation and Germination in Planta
Authors: Li Xin-Ran , Li Hong-Ju , Yuan Li , Liu Man , Shi Dong-Qiao , Liu Jie , Yang Wei-Cai 
Published: February 2014

AbstractPollen undergo a maturation process to sustain pollen viability and prepare them for germination. Molecular mechanisms controlling these processes remain largely unknown. Here, we report an Arabidopsis thaliana mutant, dayu (dau), which impairs pollen maturation and in vivo germination. Molecular analysis indicated that DAU encodes the peroxisomal membrane protein ABERRANT PEROXISOME MORPHOLOGY9 (APEM9). DAU is transiently expressed from bicellular pollen to mature pollen during male gametogenesis. DAU interacts with peroxisomal membrane proteins PEROXIN13 (PEX13) and PEX16 in planta. Consistently, both peroxisome biogenesis and peroxisome protein import are impaired in dau pollen. In addition, the jasmonic acid (JA) level is significantly decreased in dau pollen, and the dau mutant phenotype is partially rescued by exogenous application of JA, indicating that the male sterility is mainly due to JA deficiency. In addition, the phenotypic survey of peroxin mutants indicates that the PEXs most likely play different roles in pollen germination. Taken together, these data indicate that DAU/APEM9 plays critical roles in peroxisome biogenesis and function, which is essential for JA production and pollen maturation and germination.
Understanding and predicting the combined effects of climate change and land‐use change on freshwater macroinvertebrates and fish
Authors: Mantyka‐Pringle Chrystal S. , Martin Tara G. , Moffatt David B. , Linke Simon , Rhodes Jonathan R. 
Published: February 2014

Summary

Climate change and land‐use change are having substantial impacts on biodiversity world‐wide, but few studies have considered the impact of these factors together. If the combined effects of climate and land‐use change are greater than the effects of each threat individually, current conservation management strategies may be inefficient and/or ineffective. This is particularly important with respect to freshwater ecosystems because freshwater biodiversity has declined faster than either terrestrial or marine biodiversity over the last three decades.

This is the first study to model the independent and combined effects of climate change and land‐use change on freshwater macroinvertebrates and fish. Using a case study in south‐east Queensland, Australia, we built a Bayesian belief network populated with a combination of field data, simulations, existing models and expert judgment. Different land‐use and climate scenarios were used to make predictions on how the richness of freshwater macroinvertebrates and fish is likely to respond in future.

We discovered little change in richness averaged across the region, but identified important impacts and effects at finer scales. High nutrients and high runoff as a result of urbanization combined with high nutrients and high water temperature as a result of climate change and were the leading drivers of potential declines in macroinvertebrates and fish at fine scales.

Synthesis and applications. This is the first study to separate out the constituent drivers of impacts on biodiversity that result from climate change and land‐use change. Mitigation requires management actions that reduce in‐stream nutrients, slows terrestrial runoff and provides shade, to improve the resilience of biodiversity in streams. Encouragingly, the restoration of riparian habitats is identified as an important buffering tool that can mitigate the negative effects of climate change and land‐use change.