bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using radio jets of PKS J0334-3900 to probe the intra-cluster medium in A3135
Authors: Pratley L. , Johnston-Hollitt M. , Dehghan S. , Sun M. 
Published: March 2015

AbstractWe present a multi-wavelength study of the radio galaxy PKS J0334-3900, which resides at the centre of Abell 3135. Using Australia Telescope Compact Array (ATCA) observations at 1.4, 2.5, 4.6 & 8.6 GHz, we performed a detailed analysis of PKS J0334-3900. The morphology and spectral indices give physical parameters that constrain the dynamical history of the galaxy, which we use to produce a simulation of PKS J0334-3900. This simulation shows that the morphology can be generated by a wind in the intracluster medium (ICM), orbital motion caused by a companion galaxy, and precession of the black hole (BH).Additionally, ATCA polarisation data was used to obtain rotation measure values along the line of sight to PKS J0334-3900. Using our simulation we are able to infer the distance between the jets along the line of sight to be 154 ± 16 kpc, which when combined with the difference in rotation measure between the jets provides a novel new way to estimate the average magnetic field within the cluster. A lower limit to the cluster magnetic field was calculated to be 0.09±0.03 μG. We have shown that different techniques can be applied to observations of jets in galaxies to infer information on cluster environments.
Extragalactic jets as probes of distant clusters of galaxies and the clusters occupied by bent radio AGN (COBRA) survey
Authors: Blanton Elizabeth L. , Paterno-Mahler Rachel , Wing Joshua D. , Ashby M. L. N. , Golden-Marx Emmet , Brodwin Mark , Douglass E. M. , Randall Scott W. , Clarke T. E. 
Published: March 2015

AbstractWe are conducting a large survey of distant clusters of galaxies using radio sources with bent jets and lobes as tracers. These radio sources are driven by AGN and achieve their bent morphologies through interaction with the surrounding gas found in clusters of galaxies. Based on low-redshift studies, these types of sources can be used to identify clusters very efficiently. We present initial results from our survey of 653 bent-double radio sources with optical hosts too faint to appear in the SDSS. The sample was observed in the infrared with Spitzer, and it has revealed ~200 distant clusters or proto-clusters in the redshift range z ~ 0.7 - 3.0. The sample of bent-doubles contains both quasars and radio galaxies enabling us to study both radiative and kinetic mode feedback in cluster and group environments at a wide range of redshifts.
Linking the central engine to the jet properties in radio loud AGN
Authors: Olguín-Iglesias A. , León-Tavares J. , Chavushyan V. , Valtaoja E. , Añorve C. , Nilsson K. , Kotilainen J. , Tornikoski M. 
Published: March 2015

AbstractWe explore the connection between the black hole mass and its relativistic jet for a sample of radio-loud AGN (z < 1), in which the relativistic jet parameters are well estimated by means of long term monitoring with the 14m Metsähovi millimeter wave telescope and the Very Long Base-line Array (VLBA). NIR host galaxy images taken with the NOTCam on the Nordic Optical Telescope (NOT) and retrieved from the 2MASS all-sky survey allowed us to perform a detailed surface brightness decomposition of the host galaxies in our sample and to estimate reliable black hole masses via their bulge luminosities. We present early results on the correlations between black hole mass and the relativistic jet parameters. Our preliminary results suggest that the more massive the black hole is, the faster and the more luminous jet it produces.
A strong radio brightening at the jet base of M87 during the elevated very-high-energy γ-ray state in 2012
Authors: Hada K. , Giroletti M. , Kino M. , Giovannini G. , Ammando F. D' , Cheung C. C. , Beilicke M. , Nagai H. , Doi A. , Akiyama K. , Honma M. , Niinuma K. , Casadio C. , Orienti M. , Krawczynski H. , Gómez J. L. , Sawada-Satoh S. , Koyama S. , Cesarini A. , Nakahara S. , Gurwell M. A. 
Published: March 2015

AbstractThe nearby radio galaxy M87 offers a unique opportunity for exploring the connection between γ-ray production and jet formation at an unprecedented linear resolution. However, the origin and location of the γ-rays in this source is still elusive. Based on previous radio/TeV correlation events, the unresolved jet base (radio core) and the peculiar knot HST-1 at >120 pc from the nucleus are proposed as candidate site(s) of γ-ray production. Here we report our intensive, high-resolution radio monitoring observations of the M87 jet with the VLBI Exploration of Radio Astrometry (VERA) and the European VLBI Network (EVN) from February 2011 to October 2012. During this period, an elevated level of the M87 flux is reported at TeV with VERITAS. We detected a remarkable flux increase in the radio core with VERA at 22/43 GHz coincident with the VHE activity. Meanwhile, HST-1 remained quiescent in terms of its flux density and structure at radio. These results strongly suggest that the TeV γ-ray activity in 2012 originates in the jet base within 0.03 pc (projected) from the central supermassive black hole.
AGN dusty plasma polarization features
Authors: Lopez Ericson D. , Deustua Susana 
Published: March 2015

AbstractWe present the results of a theoretical study on the influence of dust particles on the polarization properties of the radiation that propagates along the jet in AGNs. First, a model for describing the interaction of dust particles, in addition to the electrons and ions, with electromagnetic radiation in a magneto-active plasma has been developed. From here, the contribution of dust particles to the Faraday rotation of the plane of polarization of the electric vector can be deduced. This model is evaluated for the outer region of the jet where the presence of dust particles are assumed, the magnetic field is weak and the electron density is low. Our results show that the dust particles give a significant contribution to the linear Faraday rotation measure.
Synergies in extragalactic and Galactic jet research
Authors: Romero Gustavo E. 
Published: March 2015

AbstractThe discovery of relativistic jets and superluminal sources associated with accreting X-ray binaries in the Galaxy opened new ways of investigating the physics of outflows from compact objects. The short timescales and relatively large angular sizes of Galactic jets allow to probe the physics of relativistic outflows to unprecedented details. In this article I discuss results of recent modelling of Galactic jets, covering both radiative and dynamical aspects, which can shed light on different features of their extragalactic cousins.
Explaining the flat-spectrum radio core Sgr A* with GRMHD simulations of jets
Authors: Mościbrodzka Monika A. 
Published: March 2015

AbstractThe supermassive black hole in the center of the Milky Way, Sgr A*, displays a nearly flat radio spectrum which is typical for jets in Active Galactic Nuclei. Indeed, time dependent, magnetized models of radiatively inefficient accretion flows, which are commonly used to explain the millimeter, near-infrared, and X-ray emission of Sgr A* also often produce jet-like outflows. However, the emission from these models so far has failed to reproduce the flat radio spectrum. We show that current GRMHD simulations can naturally reproduce the flat spectrum, when using a two-temperature plasma in the disk and a constant electron temperature plasma in the jet. This assumption is consistent with current state-of-the art simulations, in which the electron temperature evolution is not explicitly modeled. Stronger magnetization and stronger shearing seen in the jet sheath could possibly explain the difference in electron heating between jet and disk. The model images and spectra are consistent with the radio sizes and spectrum of Sgr A*.
Simulations of flux variability of oscillating accretion fluid tori around Kerr black holes
Authors: Bakala Pavel , Goluchová Kateřina , Šrámková Eva , Kotrlová Andrea , Török Gabriel , Vincent Frederic H. , Abramowicz Marek A. 
Published: March 2015

AbstractHigh frequency quasi-periodic oscillations (HF QPOs) are observed in the X-ray power-density spectra (PDS) of several microquasars and low mass X-ray binaries. Many proposed QPO models are based on oscillations of accretion toroidal fluid structures orbiting in the vicinity of a compact object. We study oscillating accretion tori orbiting in the vicinity of a Kerr black hole. We demonstrate that significant variation of the observed flux can be caused by the combination of radial and vertical oscillation modes of a slender, polytropic, perfect fluid, non-self-graviting torus with constant specific angular momentum. We investigate two combinations of the oscillating modes corresponding to the direct resonance QPO model and the modified relativistic precession QPO model.
The epidemiology of common mental disorders from age 20 to 50: results from the prospective Zurich cohort Study
Authors: Angst J. , Paksarian D. , Cui L. , Merikangas K. R. , Hengartner M. P. , Ajdacic-Gross V. , Rössler W. 
Published: March 2015

Background:There are only a small number of prospective studies that have systematically evaluated standardised diagnostic criteria for mental disorder for more than a decade. The aim of this study is to present the approximated overall and sex-specific cumulative incidence of mental disorder in the Zurich cohort study, a prospective cohort study of 18–19 years olds from the canton of Zurich, Switzerland, who were followed through age 50.Method:A stratified sample of 591 participants were interviewed with the Structured Psychopathological Interview and Rating of the Social Consequences of Psychological Disturbances for Epidemiology, a semi-structured interview that uses a bottom-up approach to assess the past-year presence of 15 psychiatric syndromes. Seven interview waves took place between 1979 and 2008. Approximated cumulative incidence was estimated using Kaplan–Meier methods.Results:Rates of mental disorder were considerably higher than those generally reported in cross-sectional surveys. We found rates ranging from 32.5% for major depressive disorder to 1.2% for Bipolar I disorder. The cumulative probability of experiencing any of the mental disorders assessed by age 50 was 73.9%, the highest reported to date. We also found that rates differed by sex for most disorders, with females generally reporting higher rates of mood, anxiety and phobic disorder, and males reporting higher rates of substance- and alcohol-related disorders.Conclusions:These findings confirm those of other long-term prospective studies that indicate the nearly universal nature of disturbances of emotion and behaviour across the life span. Greater community awareness of the normative nature of these experiences is warranted. An important area of future research is study long-term course and stability to determine who among those with such disturbances suffer from chronic disabling mental disorders. Such longitudinal studies may aid in directing services and intervention efforts where they are most needed.
Arc expression identifies the lateral amygdala fear memory trace
Authors: Gouty-Colomer L A , Hosseini B , Marcelo I M , Schreiber J , Slump D E , Yamaguchi S , Houweling A R , Jaarsma D , Elgersma Y , Kushner S A 
Published: March 2015

Abstract
Memories are encoded within sparsely distributed neuronal ensembles. However, the defining cellular properties of neurons within a memory trace remain incompletely understood. Using a fluorescence-based Arc reporter, we were able to visually identify the distinct subset of lateral amygdala (LA) neurons activated during auditory fear conditioning. We found that Arc-expressing neurons have enhanced intrinsic excitability and are preferentially recruited into newly encoded memory traces. Furthermore, synaptic potentiation of thalamic inputs to the LA during fear conditioning is learning-specific, postsynaptically mediated and highly localized to Arc-expressing neurons. Taken together, our findings validate the immediate-early gene Arc as a molecular marker for the LA neuronal ensemble recruited during fear learning. Moreover, these results establish a model of fear memory formation in which intrinsic excitability determines neuronal selection, whereas learning-related encoding is governed by synaptic plasticity.
Xanthine oxidoreductase regulates macrophage IL1β secretion upon NLRP3 inflammasome activation
Authors: Ives Annette , Nomura Johji , Martinon Fabio , Roger Thierry , LeRoy Didier , Miner Jeffrey N. , Simon Gregoire , Busso Nathalie , So Alexander 
Published: March 2015

AbstractActivation of the NLRP3 inflammasome by microbial ligands or tissue damage requires intracellular generation of reactive oxygen species (ROS). We present evidence that macrophage secretion of IL1β upon stimulation with ATP, crystals or LPS is mediated by a rapid increase in the activity of xanthine oxidase (XO), the oxidized form of xanthine dehydrogenase, resulting in the formation of uric acid as well as ROS. We show that XO-derived ROS, but not uric acid, is the trigger for IL1β release and that XO blockade results in impaired IL1β and caspase1 secretion. XO is localized to both cytoplasmic and mitochondrial compartments and acts upstream to the PI3K–AKT signalling pathway that results in mitochondrial ROS generation. This pathway represents a mechanism for regulating NLRP3 inflammasome activation that may have therapeutic implications in inflammatory diseases.
Ultimate thin vertical p–n junction composed of two-dimensional layered molybdenum disulfide
Authors: Li Hua-Min , Lee Daeyeong , Qu Deshun , Liu Xiaochi , Ryu Jungjin , Seabaugh Alan , Yoo Won Jong 
Published: March 2015

AbstractSemiconducting two-dimensional crystals are currently receiving significant attention because of their great potential to be an ultrathin body for efficient electrostatic modulation, which enables to overcome the limitations of silicon technology. Here we report that, as a key building block for two-dimensional semiconductor devices, vertical p–n junctions are fabricated in ultrathin MoS2 by introducing AuCl3 and benzyl viologen dopants. Unlike usual unipolar MoS2, the MoS2 p–n junctions show ambipolar carrier transport, current rectification via modulation of potential barrier in films thicker than 8 nm and reversed current rectification via tunnelling in films thinner than 8 nm. The ultimate thinness of the vertical p–n homogeneous junctions in MoS2 is experimentally found to be 3 nm, and the chemical doping depth is found to be 1.5 nm. The ultrathin MoS2 p–n junctions present a significant potential of the two-dimensional crystals for flexible, transparent, high-efficiency electronic and optoelectronic applications.
Microbial biofilms and the human intestinal microbiome
Authors: de Vos Willem M 
Published: March 2015

AbstractSince early life we are colonised by a myriad of microbes that make up our microbiome. This colonisation process starts at birth or even before, when the virtually sterile baby encounters new microbial environments. It is likely that at this time or at later moments in life, microbial communities are met that have high-level structures with a temporal and spatial organisation, termed biofilms. This perspective will focus on these biofilms and the microbes in the intestinal tract as these are the most numerous in the human body, are found in luminal and mucosal locations, and have a great impact on human health and disease.
Sequence variants from whole genome sequencing a large group of Icelanders
Authors: Gudbjartsson Daniel F , Sulem Patrick , Helgason Hannes , Gylfason Arnaldur , Gudjonsson Sigurjon A , Zink Florian , Oddson Asmundur , Magnusson Gisli , Halldorsson Bjarni V , Hjartarson Eirikur , Sigurdsson Gunnar Th. , Kong Augustine , Helgason Agnar , Masson Gisli , Magnusson Olafur Th. , Thorsteinsdottir Unnur , Stefansson Kari 
Published: March 2015

AbstractWe have accumulated considerable data on the genetic makeup of the Icelandic population by sequencing the whole genomes of 2,636 Icelanders to depth of at least 10X and by chip genotyping 101,584 more. The sequencing was done with Illumina technology. The median sequencing depth was 20X and 909 individuals were sequenced to a depth of at least 30X. We found 20 million single nucleotide polymorphisms (SNPs) and 1.5 million insertions/deletions (indels) that passed stringent quality control. Almost all the common SNPs (derived allele frequency (DAF) over 2%) that we identified in Iceland have been observed by either dbSNP (build 137) or the Exome Sequencing Project (ESP) while only 60 and 20% of rare (DAF<0.5%) SNPs and indels in coding regions, the most heavily studied parts of the genome, have been observed in the public databases. Features of our variant data, such as the transition/transversion ratio and the length distribution of indels, are similar to published reports.
EphB2 activation is required for ependymoma development as well as inhibits differentiation and promotes proliferation of the transformed cell
Authors: Chen Phylip , Rossi Nathan , Priddy Samuel , Pierson Christopher R. , Studebaker Adam W. , Johnson Robert A. 
Published: March 2015

AbstractOur intracranial implantation mouse model of ependymoma clearly demonstrates overexpression of the ephrin receptor EphB2 inInk4a/Arf(−/−)supratentorial embryonic neural stem cells (STeNSCs) to be essential for transformation and disease development; however the requirement for and consequence of receptor activation on transformation and neural stem cell function were not examined. We definitively illustrate the necessity for receptor activation in cellular transformation and the importance of implantation site and microenvironment in directing ependymoma development.In vitroassays of EphB2 overexpressingInk4a/Arf(−/−)STeNSCs showed no changes in their neural stem cell characteristics (stem cell marker expression and self-renewal) upon receptor activation, but EphB2 driven tumor cells were inhibited significantly in differentiation and exhibited increased tumorsphere formation and cellular proliferation in response to ephrin-B ligand mediated receptor activation. Additionally, we observed substantial differences in the phosphorylation state of several key proteins involved in Ras and p38 MAPK signaling when comparing EphB2 overexpressingInk4a/Arf(−/−)STeNSCs and tumor cells with relatively little change in total protein levels. We propose that EphB2 mediated ependymoma development is a multifactorial process requiring microenvironment directed receptor activation, resulting in changes in the phosphorylation status of key regulatory proteins, maintenance of a stem-like state and cellular proliferation.
Extraordinarily Adaptive Properties of the Genetically Encoded Amino Acids
Authors: Ilardo Melissa , Meringer Markus , Freeland Stephen , Rasulev Bakhtiyor , Cleaves II H. James 
Published: March 2015

AbstractUsing novel advances in computational chemistry, we demonstrate that the set of 20 genetically encoded amino acids, used nearly universally to construct all coded terrestrial proteins, has been highly influenced by natural selection. We defined an adaptive set of amino acids as one whose members thoroughly cover relevant physico-chemical properties, or “chemistry space.” Using this metric, we compared the encoded amino acid alphabet to random sets of amino acids. These random sets were drawn from a computationally generated compound library containing 1913 alternative amino acids that lie within the molecular weight range of the encoded amino acids. Sets that cover chemistry space better than the genetically encoded alphabet are extremely rare and energetically costly. Further analysis of more adaptive sets reveals common features and anomalies and we explore their implications for synthetic biology. We present these computations as evidence that the set of 20 amino acids found within the standard genetic code is the result of considerable natural selection. The amino acids used for constructing coded proteins may represent a largely global optimum, such that any aqueous biochemistry would use a very similar set.
Determination of the polarization states of an arbitrary polarized terahertz beam: Vectorial vortex analysis
Authors: Wakayama Toshitaka , Higashiguchi Takeshi , Oikawa Hiroki , Sakaue Kazuyuki , Washio Masakazu , Yonemura Motoki , Yoshizawa Toru , Tyo J. Scott , Otani Yukitoshi 
Published: March 2015

AbstractVectorial vortex analysis is used to determine the polarization states of an arbitrarily polarized terahertz (0.1–1.6 THz) beam using THz achromatic axially symmetric wave (TAS) plates, which have a phase retardance of Δ = 163° and are made of polytetrafluorethylene. Polarized THz beams are converted into THz vectorial vortex beams with no spatial or wavelength dispersion and the unknown polarization states of the incident THz beams are reconstructed. The polarization determination is also demonstrated at frequencies of 0.16 and 0.36 THz. The results obtained by solving the inverse source problem agree with the values used in the experiments. This vectorial vortex analysis enables a determination of the polarization states of the incident THz beam from the THz image. The polarization states of the beams are estimated after they pass through the TAS plates. The results validate this new approach to polarization detection for intense THz sources. It could find application in such cutting edge areas of physics as nonlinear THz photonics and plasmon excitation, because TAS plates not only instantaneously elucidate the polarization of an enclosed THz beam but can also passively control THz vectorial vortex beams.
Tunable Room Temperature THz Sources Based on Nonlinear Mixing in a Hybrid Optical and THz Micro-Ring Resonator
Authors: Sinha Raju , Karabiyik Mustafa , Al-Amin Chowdhury , Vabbina Phani K. , Güney Durdu Ö. , Pala Nezih 
Published: March 2015

AbstractWe propose and systematically investigate a novel tunable, compact room temperature terahertz (THz) source based on difference frequency generation in a hybrid optical and THz micro-ring resonator. We describe detailed design steps of the source capable of generating THz wave in 0.5–10 THz with a tunability resolution of 0.05 THz by using high second order optical susceptibility (χ(2)) in crystals and polymers. In order to enhance THz generation compared to bulk nonlinear material, we employ a nonlinear optical micro-ring resonator with high-Q resonant modes for infrared input waves. Another ring oscillator with the same outer radius underneath the nonlinear ring with an insulation of SiO2layer supports the generated THz with resonant modes and out-couples them into a THz waveguide. The phase matching condition is satisfied by engineering both the optical and THz resonators with appropriate effective indices. We analytically estimate THz output power of the device by using practical values of susceptibility in available crystals and polymers. The proposed source can enable tunable, compact THz emitters, on-chip integrated spectrometers, inspire a broader use of THz sources and motivate many important potential THz applications in different fields.