bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ensemble quasar spectral variability from the XMM-Newton Serendipitous Source Catalogue
Authors: Serafinelli Roberto , Vagnetti Fausto , Middei Riccardo 
Published: June 2017

AbstractVariations of the X-ray spectral slope have been found in many Active Galactic Nuclei (AGN) at moderate luminosities and redshifts, typically showing a “softer when brighter” behaviour. However, similar studies are not usually performed for high-luminosity AGNs. We present an analysis of the spectral variability based on a large sample of quasars in wide intervals of luminosity and redshift, measured at several different epochs, extracted from the fifth release of the XMM Newton Serendipitous Source Catalogue. Our analysis confirms a “softer when brighter” trend also for our sample, extending to high luminosity and redshift the general behaviour previously found. These results can be understood in light of current spectral models, such as intrinsic variations of the X-ray primary radiation, or superposition with a constant reflection component.
Radio and γ-ray loud narrow-line Seyfert 1 galaxies in the spotlight
Authors: Karamanavis V. , Angelakis E. , Komossa S. , Myserlis I. , Blinov D. , Zensus J. A. 
Published: June 2017

AbstractNarrow-line Seyfert 1 (NLS1) galaxies provide us with unique insights into the drivers of AGN activity under extreme conditions. Given their low black hole (BH) masses and near-Eddington accretion rates, they represent a class of galaxies with rapidly growing supermassive BHs in the local universe. Here, we present the results from our multi-frequency radio monitoring of a sample of γ-ray loud NLS1 galaxies (γNLS1s), including systems discovered only recently, and featuring both the nearest and the most distant γNLS1s known to date. We also present high-resolution radio imaging of 1H 0323+342, which is remarkable for its spiral or ring-like host. Finally, we present new radio data of the candidate γ-emitting NLS1 galaxy RX J2314.9+2243, characterized by a very steep radio spectrum, unlike other γNLS1s.
What can Fermi LAT observation of the Galactic Centre tell us about its active past?
Authors: Zaharijas Gabrijela , Petrović Jovana , Serpico Pasquale 
Published: June 2017

AbstractThe Fermi-LAT gamma-ray data in the inner Galaxy region show several prominent features possibly related to the past activity of the Milky Way’s super massive black hole. At a large, 50 deg scale, the Fermi LAT revealed symmetric hour glass structures with hard energy spectra extending up to 100 GeV (and dubbed ‘the Fermi bubbles’). More recently and closer to the Galactic centre, at the 10 deg scale, several groups have claimed evidence for excess gamma-ray emission that appears symmetric around the Galactic center and has an energy spectrum peaking at few GeVs. We explore here the possibility that this emission originates in inverse Compton emission from high-energy electrons produced in a short duration, burst-like event injecting 1052 − 1053 erg, roughly 106 yrs ago. Several lines of evidence suggest that a series of ‘burst like’ events happened in the vicinity of our black hole in the past and gamma-ray observations may offer a new view of that scenario.
Doppler Boosting Effect on the Jet Radiation of Gamma-Ray Bursts and Active Galactic Nuclei
Authors: Huang Xiao-Li , Zhang Hai-Ming , Zhong Shu-Qing , Liang En-Wei 
Published: June 2017

AbstractHigh energy photon radiations of gamma-ray bursts (GRBs) and active galactic nuclei (AGNs) are dominated by their jet radiations. It was suggested that relativistic jets powered by different mass-scale black holes may share the same physical laws. A tight relation among the peak luminosity, the peak photon energy in the νfν spectrum, and the initial Lorentz factor is found for GRBs. With samples of GeV-TeV BL Lacs, FSRQs, and NLS1 galaxies, we show that these sources do not follow this relation. This may be attributed to the jet geometry and continuous/episodic jet as well as radiation physics for different kinds of sources.
Lorentz Factor Evolution Patterns within Relativistic Jets of GRBs and AGNs
Authors: Zhang Hai-Ming , Lin Da-Bin , Lin Ting-Ting , Liu Bao-Rong , Huang Xiao-Li , Zhong Shu-Qing , Lu Rui-Jing , Liang En-Wei 
Published: June 2017

AbstractThe Lorentz factor (Γ) is an important parameter related to the relativistic jet physics. We study the evolution patterns of Γ within gamma-ray burst (GRB) and active galactic nuclear jets for individual GRB 090168, GRB 140508A, and 3C 454.3. By estimating the Γ values for well-separated pulses in GRBs 090618 and 140508A with an empirical relation derived from typical GRBs, we find that the Γ evolution pattern in the two GRBs are different. The increasing-to-coasting evolution pattern of Γ in GRB 090618 likely indicates that the GRB fireball is still being accelerated in the prompt phase. The clear decrease evolution pattern of Γ in GRB 140508A suggests the deceleration of the fireball components. By deriving the Γ value through fitting their spectral energy distribution in different flares of 3C 454.3, a pattern of Γ-tracking-γ-ray flux is clearly found, likely indicating that the observed gamma-ray flares are being due to the Doppler boosting effect to the jet emission.
A thin disk model for the high efficiency jet in powerful lobe-dominated FRII radio galaxies
Authors: Li Shuang-Liang 
Published: June 2017

AbstractWe propose a thin accretion disk with magnetically driven winds model to investigate the high jet efficiency phenomenon in lobe-dominated luminous FRII radio galaxies, which was reported by Fernandes et al. (2011) and Punsly (2011). It was found that the temperature of a thin disk with winds was much lower comparing with that of a standard thin disk because the winds take the most of energy released in the disk away, resulting in a much smaller raditive efficiency. Therefore, the jet efficiency can be very high even for conventional jet power. Our model can explain the observations quite well.
Search for UHE neutrinos in coincidence with LIGO GW150914 event with the Pierre Auger Observatory
Authors: Yang Lili ,   for the Pierre Auger Collaboration
Published: June 2017

AbstractThe first gravitational wave transient GW150914 was observed by Advanced LIGO on September 14th, 2015 at 09:50:45 Universal Time. In addition to follow-up electromagnetic observations, the detection of neutrinos will probe deeply and more on the nature of astrophysical sources, especially in the ultra-high energy regime. Neutrinos in the EeV energy range were searched in data collected at the surface detector of the Pierre Auger Observatory within ± 500 s and 1 day after the GW150914 event. No neutrino candidates were found. Based on this non-observation, we derive the first and only neutrino fluence upper limit at EeV energies for this event at 90% CL, and report constraints on existence of accretion disk around mergers.
The jet detection in radio-loud narrow-line Seyfert 1 galaxies
Authors: Gu Minfeng 
Published: June 2017

AbstractWith relatively small black hole masses and high accretion rates, narrow-line Seyfert 1 galaxies are thought to be young AGNs. About 7% of them are radio-loud narrow-line Seyfert 1 galaxies (RLNLS1s). RLNLS1s allow us to re-address some of the key questions regarding the physics of jet formation. As the first step of the systematic study on the jet properties of RLNLS1s, we present the radio structure of fourteen RLNLS1s from VLBA observations at 5 GHz in 2013. Although all these sources are very radio-loud with R > 100, their jet properties are diverse, in terms of their pc-scale morphology and overall radio spectral shape. The core brightness temperatures of our sources are significantly lower than those of blazars, therefore, the beaming effect is generally not significant, compared to blazars. This implies that the bulk jet speed may likely be low in our sources.
On the gamma-ray burst – gravitational wave association in GW150914
Authors: Janiuk Agnieszka , Charzynski Szymon , Bejger Michal 
Published: June 2017

AbstractHyperaccreting disks around black holes are the engines that drive outflows and jets in gamma ray bursts (GRBs). The torus formed after the core collapse or a compact binary merger is composed of free nucleons, Helium, electron-positron pairs, and is cooled by neutrinos rather than photon emission. Hyperaccretion powers the ultra-relativistic jets, where the GRB prompt emission originates. The neutrons produced in the disk and also in the outflowing material are necessary for the production of heavier nuclei. We discuss here the observable consequences of nucleosynthesis and we also apply the scenario of hyperaccretion to the gravitational wave source, GW150914. Temporal coincidence reported by the Fermi satellite suggested that the black hole merger might be accompanied with a GRB. We propose that a collapsing massive star and a black hole in a close binary could lead to such event. Gravitational wave emission due to the merger of collapsed core and the companion black hole might then coincide with a weak GRB.
Elusive Accretion Discs in Low Luminosity AGN
Authors: Fernández-Ontiveros J.A. , Escudero M.A. Prieto , Markoff S. , Reb L. , Espada D. , González-Martín O. 
Published: June 2017

AbstractLow luminosity AGN (LLAGN) represent the vast majority of the AGN population in the near universe. However, they show intrinsic differences when compared to the Unified Model scenario, i.e. a lack of both the big blue bump and the IR bump in their spectral energy distribution (SED), which are the signatures of an accretion disk and a torus, respectively. In this work we present SED for a sample of six LLAGN in the nearby Universe obtained from subarcsec resolution observations. The nature of the IR continuum emission is discussed in the context of non-thermal radiation powered by compact jets.
Quasi-Periodicities at Year Time Scales in Blazars
Authors: Covino Stefano , Sandrinelli Angela , Treves Aldo 
Published: June 2017

AbstractWe examine the 2008-2016 gamma-ray and optical light curves of a number of bright Fermi blazars. In a fraction of them, the periodograms show possible evidence of quasi-periodicities related in the two bands. This coincidence strengthens their physical meaning. Comparing with results from the periodicity search of quasars, the presence of quasi-periodicities in blazars suggests that the basic condition for its observability is related to the relativistic jet in the observer direction, but the overall picture remains uncertain.
Zika virus pathogenesis in rhesus macaques is unaffected by pre-existing immunity to dengue virus
Authors: Pantoja Petraleigh , Pérez-Guzmán Erick X. , Rodríguez Idia V. , White Laura J. , González Olga , Serrano Crisanta , Giavedoni Luis , Hodara Vida , Cruz Lorna , Arana Teresa , Martínez Melween I. , Hassert Mariah A. , Brien James D. , Pinto Amelia K. , de Silva Aravinda , Sariol Carlos A. 
Published: June 2017

AbstractZika virus (ZIKV) is a re-emerging virus that has recently spread into dengue virus (DENV) endemic regions and cross-reactive antibodies (Abs) could potentially affect ZIKV pathogenesis. Using DENV-immune serum, it has been shown in vitro that antibody-dependent enhancement (ADE) of ZIKV infection can occur. Here we study the effects of pre-existing DENV immunity on ZIKV infection in vivo. We infect two cohorts of rhesus macaques with ZIKV; one cohort has been exposed to DENV 2.8 years earlier and a second control cohort is naïve to flaviviral infection. Our results, while confirming ADE in vitro, suggest that pre-existing DENV immunity does not result in more severe ZIKV disease. Rather our results show a reduction in the number of days of ZIKV viremia compared to naïve macaques and that the previous exposure to DENV may result in modulation of the immune response without resulting in enhancement of ZIKV pathogenesis.
Optogenetic rewiring of thalamocortical circuits to restore function in the stroke injured brain
Authors: Tennant Kelly A. , Taylor Stephanie L. , White Emily R. , Brown Craig E. 
Published: June 2017

AbstractTo regain sensorimotor functions after stroke, surviving neural circuits must reorganize and form new connections. Although the thalamus is critical for processing and relaying sensory information to the cortex, little is known about how stroke affects the structure and function of these connections, or whether a therapeutic approach targeting these circuits can improve recovery. Here we reveal with in vivo calcium imaging that stroke in somatosensory cortex dampens the excitability of surviving thalamocortical circuits. Given this deficit, we hypothesized that chronic transcranial window optogenetic stimulation of thalamocortical axons could facilitate recovery. Using two-photon imaging, we show that optogenetic stimulation promotes the formation of new and stable thalamocortical synaptic boutons, without impacting axon branch dynamics. Stimulation also enhances the recovery of somatosensory cortical circuit function and forepaw sensorimotor abilities. These results demonstrate that an optogenetic approach can rewire thalamocortical circuits and restore function in the damaged brain.
Single-virus genomics reveals hidden cosmopolitan and abundant viruses
Authors: Martinez-Hernandez Francisco , Fornas Oscar , Lluesma Gomez Monica , Bolduc Benjamin , de la Cruz Peña Maria Jose , Martínez Joaquín Martínez , Anton Josefa , Gasol Josep M. , Rosselli Riccardo , Rodriguez-Valera Francisco , Sullivan Matthew B. , Acinas Silvia G. , Martinez-Garcia Manuel 
Published: June 2017

AbstractMicrobes drive ecosystems under constraints imposed by viruses. However, a lack of virus genome information hinders our ability to answer fundamental, biological questions concerning microbial communities. Here we apply single-virus genomics (SVGs) to assess whether portions of marine viral communities are missed by current techniques. The majority of the here-identified 44 viral single-amplified genomes (vSAGs) are more abundant in global ocean virome data sets than published metagenome-assembled viral genomes or isolates. This indicates that vSAGs likely best represent the dsDNA viral populations dominating the oceans. Species-specific recruitment patterns and virome simulation data suggest that vSAGs are highly microdiverse and that microdiversity hinders the metagenomic assembly, which could explain why their genomes have not been identified before. Altogether, SVGs enable the discovery of some of the likely most abundant and ecologically relevant marine viral species, such as vSAG 37-F6, which were overlooked by other methodologies.
Determinants of initial inhaled corticosteroid use in patients with GOLD A/B COPD: a retrospective study of UK general practice
Authors: Chalmers James D. , Tebboth Abigail , Gayle Alicia , Ternouth Andrew , Ramscar Nick 
Published: June 2017

AbstractInitial use of inhaled corticosteroid therapy is common in patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) A or B chronic obstructive pulmonary disease, contrary to GOLD guidelines. We investigated UK prescribing of inhaled corticosteroid therapy in these patients, to identify predictors of inhaled corticosteroid use in newly diagnosed chronic obstructive pulmonary disease patients. A cohort of newly diagnosed GOLD A/B chronic obstructive pulmonary disease patients was identified from the UK Clinical Practice Research Datalink (June 2005–June 2015). Patients were classified by prescribed treatment, with those receiving inhaled corticosteroid-containing therapy compared with those receiving long-acting bronchodilators without inhaled corticosteroid. In all, 29,815 patients with spirometry-confirmed chronic obstructive pulmonary disease were identified. Of those prescribed maintenance therapy within 3 months of diagnosis, 63% were prescribed inhaled corticosteroid-containing therapy vs. 37% prescribed non-inhaled corticosteroid therapy. FEV1% predicted, concurrent asthma diagnosis, region, and moderate exacerbation were the strongest predictors of inhaled corticosteroid use in the overall cohort. When concurrent asthma patients were excluded, all other co-variates remained significant predictors. Other significant predictors included general practitioner practice, younger age, and co-prescription with short-acting bronchodilators. Trends over time showed that initial inhaled corticosteroid prescriptions reduced throughout the study, but still accounted for 47% of initial prescriptions in 2015. These results suggest that inhaled corticosteroid prescribing in GOLD A/B patients is common, with significant regional variation that is independent of FEV1% predicted.
Expression analysis of inflammasome sensors and implication of NLRP12 inflammasome in prostate cancer
Authors: Karan Dev , Tawfik Ossama , Dubey Seema 
Published: June 2017

AbstractInflammasomes are multi-proteins complex regulating inflammation-associated signaling. While inflammation plays a critical role in cancer cell growth, studies remain uncharacterized on the role of inflammasomes in prostate cancer. Using Gene Expression Omnibus (GEO) public datasets, we screened the expression profiles of inflammasome sensors NLRP3, NLRC4, NLRP6, NRLP12, and AIM2 in prostate tumor tissues, and verified their mRNA level in a panel of prostate cancer cell lines. The selected expression of NLRP3 and NLRP12 inflammasomes was validated, and the clinical association was evaluated in human prostate archival tumor tissues. We observed that the expression of inflammasome sensors was dysregulated at the mRNA level except for the NLRP12. The intensity of NLRP12 immunostaining was significantly higher in malignant prostate as compared to their adjacent benign tissues. In contrast, the NLRP3 immunostaining in prostate tissues was heterogeneous. The inflammasome complex proteins ASC (apoptosis-associated speck-like protein containing a CARD) and pro-caspase-1, as well as its downstream targets IL-1β and IL-18 were confined to aggressive prostate cancer cells. These data suggest an increased expression of NLRP12 in association with prostate cancer and support the role of NLRP12 inflammasome complex regulating inflammatory cytokines in understanding the role of inflammation in the prostate cancer.
Sewage outburst triggers Trichodesmium bloom and enhance N2 fixation rates
Authors: Rahav Eyal , Bar-Zeev Edo 
Published: June 2017

AbstractThe southeastern Mediterranean Sea (SEMS) is a warm and sunlit marine environment with low ambient N concentration, thus considered ideal for diazotrophy by autotrophic diazotrophs such as Trichodesmium. Despite the favorable conditions, N2 fixation rates are often low and Trichodesmium has hardly been spotted in the SEMS. This study reports on the occurrence of a Trichodesmium bloom in the SEMS which was ascribed to T. erythraeum according to DNA fingerprinting of the nifH gene. We found that this bloom (1407 ± 983 cells L−1) was triggered by an intense outburst of raw sewage that supplied high concentrations of N, P and dissolved organic carbon (DOC), which resulted in low N:P (~12:1) and exceptionally high C:P (~1340:1) ratios. We surmise that these conditions provided favorable conditions for Trichodesmium bloom to form via mixotrophic metabolism. As a result, a fourfold increase in N2 fixation was recorded, which contributed ~70% to new primary production and spur a sharp increase in phytoplankton activity and biomass. The conclusions of this study point on a new paradigm for bloom-forming T. erythraeum which is tightly linked to anthropogenic sources and prompt microbial productivity in oligotrophic marine environments such as the SEMS.
Angiotensin type 2 receptor activation promotes browning of white adipose tissue and brown adipogenesis
Authors: Than Aung , Xu Shaohai , Li Ru , Leow MelvinKhee-Shing , Sun Lei , Chen Peng 
Published: June 2017

AbstractBrown adipose tissue dissipates energy in the form of heat. Recent studies have shown that adult humans possess both classical brown and beige adipocytes (brown-like adipocytes in white adipose tissue, WAT), and stimulating brown and beige adipocyte formation can be a new avenue to treat obesity. Angiotensin II (AngII) is a peptide hormone that plays important roles in energy metabolism via its angiotensin type 1 or type 2 receptors (AT1R and AT2R). Adipose tissue is a major source of AngII and expresses both types of its receptors, implying the autocrine and paracrine role of AngII in regulating adipose functions and self-remodeling. Here, based on the in vitro studies on primary cultures of mouse white adipocytes, we report that, AT2R activation, either by AngII or AT2R agonist (C21), induces white adipocyte browning, by increasing PPARγ expression, at least in part, via ERK1/2, PI3kinase/Akt and AMPK signaling pathways. It is also found that AngII–AT2R enhances brown adipogenesis. In the in vivo studies on mice, administration of AT1R antagonist (ZD7155) or AT2R agonist (C21) leads to the increase of WAT browning, body temperature and serum adiponectin, as well as the decrease of WAT mass and the serum levels of TNFα, triglycerides and free fatty acids. In addition, AT2R-induced browning effect is also observed in human white adipocytes, as evidenced by the increased UCP1 expression and oxygen consumption. Finally, we provide evidence that AT2R plays important roles in hormone T3-induced white adipose browning. This study, for the first time, reveals the browning and brown adipogenic effects of AT2R and suggests a potential therapeutic target to combat obesity and related metabolic disorders.
Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis: A Review
Authors: Chughtai Morad , Khlopas Anton , Harwin Steven , Miniaci Anthony , Mont Michael , Muschler George , Piuzzi Nicolas 
Published: June 2017

AbstractPlatelet-rich plasma (PRP) consists of a volume of plasma with a platelet concentration above whole blood baseline values. Based on the group of bioactive molecules that platelets release when activated and the regenerative and healing potential they have, the use of PRP has followed a rapid development and application in orthopedics, with applications that frequently outpaces the basic science and clinical evidence supporting its use. Currently, significant heterogeneity and discrepancies exist between the different types of available PRP formulations. Because of this, although there is a vast literature on PRP, the published results are often contradictory, making it challenging to obtain definitive conclusions. Therefore, the purpose of this review article is to provide an overview of PRP with a focus on (1) preparation protocols; (2) nomenclature and classifications; (3) biological effects; and (4) clinical evidence of its role in the treatment of knee osteoarthritis. On the basis of the current evidence, although PRP injections reduced pain and improved function more efficiently when compared with controls, these findings need to be interpreted with caution due to the limited level of evidence and high risk of bias. There is a need for a standardized scientific approach for analyzing PRP formulations composition, beginning with standardization of PRP preparation protocols, and detailed characterization of the final product (e.g., platelets and leukocytes content, volume, growth factors profile). Good quality and sizeable double-blinded randomized trials will be required to establish whether or not PRP injections are effective and should be included as a standard of care for the management of patients with knee osteoarthritis.