bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tracing the high energy emission of γ-ray detected radio loud quasars
Authors: Migliori Giulia 
Published: March 2015

AbstractWe present a multiwavelength study of the core and relativistic jet of the radio loud (RL) quasar RGB J1512+020A (z=0.20). We report the discovery of a bright, 13” extended X-ray jet with a short Chandra observation. We discuss the origin of the jet X-ray emission and its properties in comparison with sample of X-ray quasar jets. The broadband core spectrum is contributed by the emission of the central quasar, by a blazar component, responsible for the γ-ray emission detected by Fermi, and by the host galaxy. We model the non-thermal blazar spectral energy distribution (SED) and constrain the total jet power. The jet power inferred from the blazar SED modeling is in agreement with the values obtained from the total radio power, pointing to a jet that efficiently carries its power up to kiloparsec scales. The quasar emission appears intrinsically weak in the optical-UV band. The disk luminosity estimated from the broad emission lines is lower than the jet power, in agreement with recent results from observations and theory.
Unraveling AGN feedback and ICM physics with deep Chandra X-ray observations of the galaxy group NGC 5813
Authors: Randall Scott W. , Nulsen Paul E. J. , Jones Christine , Forman William R. , Clarke Tracy E. , Blanton Elizabeth L. 
Published: March 2015

AbstractWe present results from deep Chandra X-ray observations of the galaxy group NGC 5813. This system shows three pairs of collinear cavities, with each pair associated with an elliptical AGN outburst shock. Due to the relatively regular morphology of this system, and the unique unambiguous detection of three distinct AGN outburst shocks, it is particularly well-suited for the study of AGN feedback and the AGN outburst history. We find that the mean kinetic power is roughly the same for each outburst, and that the total energy associated with the youngest outburst is significantly lower than that of the previous outbursts. This implies that the mean AGN jet power has remained stable for at least 50 Myr, and that the youngest outburst is ongoing. We find that the mean shock heating rate balances the local radiative cooling rate at each shock front, suggesting that AGN outburst shock heating alone is sufficient to offset cooling and establish AGN/ICM feedback within at least the central 30 kpc. Finally, we find non-zero shock front widths that are too large to be explained by particle diffusion, but are instead consistent with arising from broadening of the shock fronts due to propagation through a turbulent ICM with a mean turbulent speed of ~ 70 km s−1.
The cluster environments of radio-loud AGN
Authors: Ineson Judith , Croston Judith , Hardcastle Martin , Kraft Ralph , Evans Daniel , Jarvis Matt 
Published: March 2015

AbstractRadio-loud AGN play an important rôle in galaxy evolution. We need to understand their properties, and the processes that affect their behaviour in order to model galaxy formation and development. We here present preliminary results of an investigation into the cluster environments of radio galaxies. We have found evidence of a strong correlation between radio luminosity and environment richness for low excitation radio galaxies, and no evidence of evolution of the environment with redshift. Conversely, for high excitation radio galaxies, we found no correlation with environment richness, and tentative evidence of evolution of the cluster environment.
Using the morphology and magnetic fields of tailed radio galaxies as environmental probes
Authors: Johnston-Hollitt M. , Dehghan S. , Pratley L. 
Published: March 2015

AbstractBent-tailed (BT) radio sources have long been known to trace over densities in the Universe up to z ~ 1 and there is increasing evidence this association persists out to redshifts of 2. The morphology of the jets in BT galaxies is primarily a function of the environment that they have resided in and so BTs provide invaluable clues as to their local conditions. Thus, not only can samples of BT galaxies be used as signposts of large-scale structure, but are also valuable for obtaining a statistical measurement of properties of the intra-cluster medium including the presence of cluster accretion shocks & winds, and as historical anemometers, preserving the dynamical history of their surroundings in their jets. We discuss the use of BTs to unveil large-scale structure and provide an example in which a BT was used to unlock the dynamical history of its host cluster. In addition to their use as density and dynamical indicators, BTs are useful probes of the magnetic field on their environment on scales which are inaccessible to other methods. Here we discuss a novel way in which a particular sub-class of BTs, the so-called ‘corkscrew’ galaxies might further elucidate the coherence lengths of the magnetic fields in their vicinity. Given that BTs are estimated to make up a large population in next generation surveys we posit that the use of jets in this way could provide a unique source of environmental information for clusters and groups up to z = 2.
Pinpointing the base of the AGN jets through general relativistic X-ray reverberation studies
Authors: Emmanoulopoulos D. 
Published: March 2015

AbstractMany theoretical models of Active Galactic Nuclei (AGN) predict that the X-ray corona, lying above the black hole, constitutes the base of the X-ray jet. Thus, by studying the exact geometry of the close black hole environment, we can pinpoint the launching site of the jet. Detection of negative X-ray reverberation time delays (i.e. soft band X-ray variations lagging behind the corresponding hard band X-ray variations) can yield significant information about the geometrical properties of the AGN, such as the location of the X-ray source, as well as the physical properties of the the black hole, such as its mass and spin. In the frame-work of the lamp-post geometry, I present the first systematic X-ray time-lag modelling results of an ensemble of 12 AGN, using a fully general relativistic (GR) ray tracing approach for the estimation of the systems' response functions. By combing these state-of-the art GR response models with statistically innovative fitting routines, I derive the geometrical layout of the close BH environment for each source, unveiling the position of the AGN jet-base.
Jet-induced star formation by a microquasar
Authors: Mirabel I. F. , Chaty S. , Rodríguez L. F. , Sauvage M. 
Published: March 2015

AbstractTheoretical and observational work show that jets from AGN can trigger star formation. However, in the Milky Way the first -and so far- only clear case of relativistic jets inducing star formation has been found in the surroundings of the microquasar GRS 1915+105. Here we summarize the multiwavelength observations of two compact star formation IRAS sources axisymmetrically located and aligned with the position angle of the sub-arcsec relativistic jets from the stellar black hole binary GRS 1915+105 (Mirabel & Rodríguez 1994). The observations of these two star forming regions at centimeter (Mirabel & Rodríguez 1998), millimeter and infrared (Chaty et al. 2001) wavelengths had suggested -despite the large uncertainties in the distances a decade ago- that the jets from GRS 1915+105 are triggering along the radio jet axis the formation of massive stars in a radio lobe of bow shock structure. Recently, Reid et al. (2014) found that the jet source and the IRAS sources are at the same distance, enhancing the evidence for the physical association between the jets from GRS 1915+105 and star formation in the IRAS sources. We conclude that as jets from AGN, jets from microquasars can trigger the formation of massive stars, but at distances of a few tens of parsecs. Although star formation induced by microquasar jets may not be statistically significant in the Milky Way, jets from stellar black holes may have been important to trigger star formation during the re-ionization epoch of the universe (Mirabel et al. 2011). Because of the relative proximity of GRS 1915+105 and the associated star forming regions, they may serve as a nearby laboratory to gain insight into the physics of jet-trigger star formation elsewhere in the universe.
Gas outflow in Seyfert galaxies: 3D radiative cooling hydrodynamical simulations
Authors: Melioli Claudio , de Gouveia Dal Pino Elisabete M. 
Published: March 2015

AbstractAccreting supermassive black holes and starburst regions influence their host galaxies through kinetic/radiative feedback processes. To better understand the gas evolution of a Seyfert galaxy, in this study we perform fully 3D hydrodynamical simulations with radiative cooling considering the presence of star formation regions, supernova feedback and small-scale (1 kpc) jet propagation in the central region of an active spiral galaxy. We compute the gas mass lost by the system and we conclude that a kpc-scale outflow is generally established only when a nuclear starburst region is coupled to a supermassive black hole jet.
Fourier plane modeling of the jet in the galaxy M81
Authors: Ramessur Arvind , Bietenholz Michael F. , Leeuw Lerothodi L. , Bartel Norbert 
Published: March 2015

AbstractThe nearby spiral galaxy M81 has a low-luminosity Active Galactic Nucleus in its center with a core and a one-sided curved jet, dubbed M81*, that is barely resolved with VLBI. To derive basic parameters such as the length of the jet, its orientation and curvature, the usual method of model-fitting with point sources and elliptical Gaussians may not always be the most appropriate one. We are developing Fourier-plane models for such sources, in particular an asymmetric triangle model to fit the extensive set of VLBI data of M81* in the u-v plane. This method may have an advantage over conventional ones in extracting information close to the resolution limit to provide us with a more comprehensive picture of the structure and evolution of the jet. We report on preliminary results.
First spectroscopy of a short-hard GRB: the environment of a compact object merger
Authors: de Ugarte Postigo Antonio , Thöne Christina C. , Rowllinson Antonia , Benito Rubén García , Levan Andrew J. , Gorosabel Javier , Goldoni Paolo , Schulze Steve 
Published: March 2015

AbstractShort gamma-ray bursts (GRBs) are an extremely elusive family of cosmic explosions. They are thought to be related to the violent merger of compact objects (such as a neutron stars or black holes). Their optical counterparts were not discovered until 2005, and since then, there had been no successful spectroscopic observations. Here we present the first spectra of a short GRB, which we use to study the environment and derive implications on the progenitors of these cosmic explosions. This poster is based on the work by de Ugarte Postigoet al. (2014).
Dissecting meiotic recombination based on tetrad analysis by single-microspore sequencing in maize
Authors: Li Xiang , Li Lin , Yan Jianbing 
Published: March 2015

AbstractMeiotic recombination drives eukaryotic sexual reproduction and the generation of genome diversity. Tetrad analysis, which examines the four chromatids resulting from a single meiosis, is an ideal method to study the mechanisms of homologous recombination. Here we develop a method to isolate the four microspores from a single tetrad in maize for the purpose of whole-genome sequencing. A high-resolution recombination map reveals that crossovers are unevenly distributed across the genome and are more likely to occur in the genic than intergenic regions, especially common in the 5′- and 3′-end regions of annotated genes. The direct detection of genomic exchanges suggests that conversions likely occur in most crossover tracts. Negative crossover interference and weak chromatid interference are observed at the population level. Overall, our findings further our understanding of meiotic recombination with implications for both basic and applied research.
Flexible pulse-controlled fiber laser
Authors: Liu Xueming , Cui Yudong 
Published: March 2015

AbstractControlled flexible pulses have widespread applications in the fields of fiber telecommunication, optical sensing, metrology and microscopy. Here, we report a compact pulse-controlled all-fiber laser by exploiting an intracavity fiber Bragg grating (FBG) system as a flexible filter. The width and wavelength of pulses can be tuned independently by vertically and horizontally translating a cantilever beam, respectively. The pulse width of the laser can be tuned flexibly and accurately from ~7 to ~150 ps by controlling the bandwidth of FBG. The wavelength of pulse can be tuned precisely with the range of >20 nm. The flexible laser is precisely controlled and insensitive to environmental perturbations. This fiber-based laser is a simple, stable and low-cost source for various applications where the width-tunable and/or wavelength-tunable pulses are necessary.
Caught in Action: Selecting Peptide Aptamers Against Intrinsically Disordered Proteins in Live Cells
Authors: Cobbert Jacqueline D. , DeMott Christopher , Majumder Subhabrata , Smith Eric A. , Reverdatto Sergey , Burz David S. , McDonough Kathleen A. , Shekhtman Alexander 
Published: March 2015

AbstractIntrinsically disordered proteins (IDPs) or unstructured segments within proteins play an important role in cellular physiology and pathology. Low cellular concentration, multiple binding partners, frequent post-translational modifications and the presence of multiple conformations make it difficult to characterize IDP interactions in intact cells. We used peptide aptamers selected by using the yeast-two-hybrid scheme and in-cell NMR to identify high affinity binders to transiently structured IDP and unstructured segments at atomic resolution. Since both the selection and characterization of peptide aptamers take place inside the cell, only physiologically relevant conformations of IDPs are targeted. The method is validated by using peptide aptamers selected against the prokaryotic ubiquitin-like protein, Pup, of the mycobacterium proteasome. The selected aptamers bind to distinct sites on Pup and have vastly different effects on rescuing mycobacterial proteasome substrate and on the survival of the Bacille-Calmette-Guèrin, BCG, strain of M. bovis. This technology can be applied to study the elusive action of IDPs under near physiological conditions.
Effects of the Fukushima Daiichi nuclear accident on goshawk reproduction
Authors: Murase Kaori , Murase Joe , Horie Reiko , Endo Koichi 
Published: March 2015

AbstractAlthough the influence of nuclear accidents on the reproduction of top predators has not been investigated, it is important that we identify the effects of such accidents because humans are also top predators. We conducted field observation for 22 years and analysed the reproductive performance of the goshawk (Accipiter gentilis fujiyamae), a top avian predator in the North Kanto area of Japan, before and after the accidents at the Fukushima Daiichi nuclear power plant that occurred in 2011. The reproductive performance declined markedly compared with the pre-accident years and progressively decreased for the three post-accident study years. Moreover, it was suggested that these declines were primarily caused by an increase in the air dose rate of radio-active contaminants measured under the nests caused by the nuclear accidents, rather than by other factors. We consider the trends in the changes of the reproductive success rates and suggest that internal exposure may play an important role in the reproductive performance of the goshawk, as well as external exposure.
The real vampires of New Orleans and Buffalo: a research note towards comparative ethnography
Authors: Browning John Edgar 
Published: March 2015

AbstractThis research note is an elaboration of my ethnographic work of the last 5 years and is here presented to raise careful discussion of the little-explored identity and phenomenon of “real vampirism”. An auxiliary purpose of these preliminary findings is to draw attention specifically to a yet unexplored dimension of the real vampire identity: geographical specificity. This line of enquiry is informed by the intensive ethnographic fieldwork I conducted in 2009–2011 in the New Orleans metropolitan area, and by supplementary ethnographic work in 2011–2013 in Buffalo, New York. Also explored is what I term “defiant culture”, through which, I posit, vampire self-identification is able to achieve a measure of empowerment by resisting “normalcy” while critiquing and challenging the power structures that re/produce it.
Continental erosion and the Cenozoic rise of marine diatoms
Authors: Cermeño Pedro , Falkowski Paul G. , Romero Oscar E. , Schaller Morgan F. , Vallina Sergio M. 
Published: March 2015

Significance
Diatoms are silica-precipitating microalgae responsible for roughly one-fifth of global primary production. The mechanisms that led these microorganisms to become one of the most prominent primary producers on Earth remain unclear. We explore the linkage between the erosion of continental silicates and the ecological success of marine diatoms over the last 40 My. We show that the diversification and geographic expansion of diatoms coincide with periods of increased continental weathering fluxes and silicic acid input to the oceans. On geological time scales, the ocean’s biologically driven sequestration of organic carbon (the biological pump) is proportional to the input flux of inorganic nutrients to the oceans. Our results suggest that the strength and efficiency of the biological pump increased over geological time.
Modulation of orthogonal body waves enables high maneuverability in sidewinding locomotion
Authors: Astley Henry C. , Gong Chaohui , Dai Jin , Travers Matthew , Serrano Miguel M. , Vela Patricio A. , Choset Howie , Mendelson Joseph R. , Hu David L. , Goldman Daniel I. 
Published: March 2015

Significance
We examined the turning behavior of snakes performing sidewinding locomotion using a hypothesized two-wave control template. Sidewinders achieved exceptional maneuverability using two types of turns, shallow differential turns and sharp reversal turns, which we hypothesized are controlled by modulating horizontal wave amplitude and vertical wave phase offset, respectively. We tested these hypothesized control schemes using a modular snake robot capable of sidewinding, resulting in similar behaviors, and explored two-wave parameter space, resulting in discovery of a third turning mechanism that is not seen in snakes. Thus, we show that complex behaviors such as turning while sidewinding can emerge from independent modulations of each of the two waves comprising this control template, underscoring the utility of robots to test biological hypotheses.
Structural and kinetic analysis of protein-aggregate strains in vivo using binary epitope mapping
Authors: Bergh Johan , Zetterström Per , Andersen Peter M. , Brännström Thomas , Graffmo Karin S. , Jonsson P. Andreas , Lang Lisa , Danielsson Jens , Oliveberg Mikael , Marklund Stefan L. 
Published: March 2015

Significance
The levels of aggregated specific proteins in the CNS in neurodegenerative diseases are minute, hampering analysis of structure and growth kinetics. Here we describe a generally applicable method based on binary epitope mapping. It was applied to analysis of superoxide dismutase aggregation in amyotrophic lateral sclerosis model mice. Two different strains of aggregates with different structures, physical stabilities, and growth kinetics were readily distinguished. Moreover, they were different from superoxide dismutase aggregates formed in vitro under a variety of conditions, revealing a key role of the CNS in shaping the aggregation process.
Using wavelength and slope to infer the historical origin of semiarid vegetation bands
Authors: Sherratt Jonathan A. 
Published: March 2015

Significance
Self-organized vegetation patterns are a characteristic feature of semiarid regions. On gentle slopes banded patterns (stripes) are typical, and their wavelength is probably the most accessible statistic for patterned vegetation. Recent data show that on steeper slopes wavelengths are usually shorter, contradicting previous predictions of mathematical models. I resolve this “contradiction” by a detailed theoretical study of pattern generation. Moreover I show that the wavelength–slope relationship has a wholly unexpected predictive power, enabling one to infer whether the patterns arose from degradation of uniform vegetation or colonization of bare ground. When combined with climate records, this gives valuable insights into the historical origin of the patterns.
Tunable molecular orientation and elevated thermal stability of vapor-deposited organic semiconductors
Authors: Dalal Shakeel S. , Walters Diane M. , Lyubimov Ivan , de Pablo Juan J. , Ediger M. D. 
Published: March 2015

Significance
Glasses are solids that lack the regular order of crystals. Organic glasses, when produced by deposition from the vapor, can exhibit high levels of molecular orientation that improve performance of devices such as organic light-emitting diodes. We show here that molecular orientation in such glasses is primarily controlled by the substrate temperature during deposition, suggesting that the performance of almost any device based upon amorphous organic materials might be systematically optimized by this route. We explain molecular orientation in the glass in terms of the orientation present near the surface of the corresponding liquid. The highly oriented glasses formed here also exhibit high density and improved thermal stability. These features will likely further enhance the performance of organic electronics devices.
β-Arrestin–biased signaling mediates memory reconsolidation
Authors: Liu Xing , Ma Li , Li Hao Hong , Huang Bing , Li You Xing , Tao Ye Zheng , Ma Lan 
Published: March 2015

Significance
β-Adrenergic receptors (β-ARs) are hormone and neurotransmitter receptors. The data we present in this paper challenge the assumption that memory reconsolidation is governed by the traditional β-AR/G protein signaling pathway. We found that memory reconsolidation is mediated by a β-arrestin–dependent β-adrenergic signaling pathway. Our experiments demonstrate that upon memory retrieval, a β1-AR/β-arrestin2/ERK pathway is activated in distinct brain areas, stimulating de novo protein synthesis and inducing postretrieval memory restabilization. Moreover, memory reconsolidation can be disrupted by propranolol, but not biased β-blockers such as carvedilol and alprenolol. Our study thus demonstrates that memory reconsolidation is mediated by a β-arrestin–biased β-adrenergic signaling pathway and reveals the therapeutic potential for β-arrestin–biased ligands in the treatment of memory-related disorders.
SWI/SNF chromatin-remodeling complexes function in noncoding RNA-dependent assembly of nuclear bodies
Authors: Kawaguchi Tetsuya , Tanigawa Akie , Naganuma Takao , Ohkawa Yasuyuki , Souquere Sylvie , Pierron Gerard , Hirose Tetsuro 
Published: March 2015

Significance
The postgenomic era has seen the identification of numerous long noncoding RNA (lncRNAs) in mammalian cells; however, their biological functions remain largely unknown. Nuclear paraspeckle assembly transcript 1 (NEAT1) is an lncRNA that participates in the construction of the massive ribonucleoprotein subnuclear complex, the paraspeckle. Paraspeckle formation proceeds in conjunction with NEAT1 biogenesis and the assembly of >40 proteins. Here, we demonstrate that SWItch/Sucrose NonFermentable (SWI/SNF) chromatin-remodeling complexes play an essential role in organizing the protein–protein interaction network of paraspeckles in a manner that does not require their canonical remodeling activity. We also show that SWI/SNF complexes are required for the assembly of the Satellite III lncRNA-dependent nuclear stress body. These data suggest the presence of a common pathway for the assembly of lncRNA-dependent nuclear bodies in mammalian cells.