86,762 research outputs found

    FR0 CAT: a FIRST catalog of FR 0 radio galaxies

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    With the aim of exploring the properties of the class of FR 0 radio galaxies, we selected a sample of 108 compact radio sources, called FR0CAT, by combining observations from the NVSS, FIRST, and SDSS surveys. We included in the catalog sources with redshift ≤0.05, with a radio size ≲5 kpc, and with an optical spectrum characteristic of low-excitation galaxies. Their radio luminosities at 1.4 GHz are in the range 1038 ≲ νL1.4 ≲ 1040 erg s-1. The FR0CAT hosts are mostly (86%) luminous (−21 ≳ Mr ≳ −23) red early-type galaxies with black hole masses 108 ≲ MBH ≲ 109M⊙. These properties are similar to those seen for the hosts of FR I radio galaxies, but they are on average a factor ~1.6 less massive. The number density of FR0CAT sources is ~5 times higher than that of FR Is, and thus they represent the dominant population of radio sources in the local Universe. Different scenarios are considered to account for the smaller sizes and larger abundance of FR 0s with respect to FR Is. An age-size scenario that considers FR 0s as young radio galaxies that will all eventually evolve into extended radio sources cannot be reconciled with the large space density of FR 0s. However, the radio activity recurrence, with the duration of the active phase covering a wide range of values and with short active periods strongly favored with respect to longer ones, might account for their large density number. Alternatively, the jet properties of FR 0s might be intrinsically different from those of the FR Is, the former class having lower bulk Lorentz factors, possibly due to lower black hole spins. Our study indicates that FR 0s and FR I/IIs can be interpreted as two extremes of a continuous population of radio sources that is characterized by a broad distribution of sizes and luminosities of their extended radio emission, but shares a single class of host galaxies

    Evaluation of double focal plane exposure technique for 248-nm and 193-nm lithography for semidense trenches and contacts

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    Double focal plane exposure technique has the property to increase greatly the depth of focus of a lithographic process and appears to be a solution to fulfil the requirements of the most aggressive lithographic targets. The purpose of this work is to investigate the performances of this technique and to understand its mechanisms, to be able to find the best conditions of use for a given process.A simple model based on aerial images considerations has been developed to determine the behaviours of the main lithographic parameters (DoFmax, Elmax, central dose, shape of the Bossung curves) for various values of die distance between the two focal planes. Comparisons with four experiments have been realized with different conditions (type of pattern, dimensions, wavelength, N.A. and coherence sigma). The possibility to predict the best experimental conditions (trade-off between DoF, El, resolution and LER) has been verified

    Nanoformulated Antiretrovirals for Penetration of the Central Nervous System: State of the Art

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    The central nervous system is a very challenging HIV-1 sanctuary. But, despite complete suppression of plasmatic viral replication with current antiretroviral therapy, signs of HIV-1 replication can still be found in the cerebrospinal fluid in some patients. The main limitation to achieving HIV-1 eradication from the brain is related to the suboptimal concentrations of antiretrovirals within this site, due to their low permeation across the blood–brain barrier. In recent years, a number of reliable nanotechnological strategies have been developed with the aim of enhancing antiretroviral drug penetration across the blood–brain barrier. The aim of this review is to provide an overview of the different nanoformulated antiretrovirals, used in both clinical and preclinical studies, that are designed to improve their delivery into the brain by active or passive permeation mechanisms through the barrier. Different nanotechnological approaches have proven successful for optimizing antiretrovirals delivery to the central nervous system, with a likely benefit for HIV-associated neurocognitive disorders and a more debated contribution to the complete eradication of the HIV-1 infection

    Properties of X-ray sources in the Selected Area 57

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    Edited by L. Lanteri, C.M. Raiteri, A. Capetti, and P. Rossi. . Available online at agn8.oato.inaf.it

    FRICAT: A FIRST catalog of FR I radio galaxies

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    We built a catalog of 219 FR I radio galaxies (FR Is), called FRICAT, selected from a published sample and obtained by combining observations from the NVSS, FIRST, and SDSS surveys. We included in the catalog the sources with an edge-darkened radio morphology, redshift ≤ 0.15, and extending (at the sensitivity of the FIRST images) to a radius r larger than 30 kpc from the center of the host. We also selected an additional sample (sFRICAT) of 14 smaller (10 < r < 30 kpc) FR Is, limiting to z < 0.05. The hosts of the FRICAT sources are all luminous (−21 ≳ Mr ≳ −24), red early-type galaxies with black hole masses in the range 108 ≲ MBH ≲ 3 × 109M⊙; the spectroscopic classification based on the optical emission line ratios indicates that they are all low excitation galaxies. Sources in the FRICAT are then indistinguishable from the FR Is belonging to the Third Cambridge Catalogue of Radio Sources (3C) on the basis of their optical properties. Conversely, while the 3C-FR Is show a strong positive trend between radio and [O III] emission line luminosity, these two quantities are unrelated in the FRICAT sources; at a given line luminosity, they show radio luminosities spanning about two orders of magnitude and extending to much lower ratios between radio and line power than 3C-FR Is. Our main conclusion is that the 3C-FR Is just represent the tip of the iceberg of a much larger and diverse population of FR Is

    X-ray variability of serendipitous AGNs discovered in Swift GRB Fields

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    Edited by L. Lanteri, C.M. Raiteri, A. Capetti, and P. Rossi. . Available online at agn8.oato.inaf.it

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    A 20 kiloparsec bipolar Lyman

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    The study of ionized gas kinematics in high-z active galaxies plays a key part in our understanding of galactic evolution, in an age where nuclear activity was widespread and star formation close to its peak. We present a study of TXS 0952−217, a radio galaxy at z = 2.95, using VLT/MUSE integral field optical spectroscopy as part of a project aimed studying of the properties of ionized gas in high redshift radio galaxies (HzRGs). The Lyα line profile of this object presents various emission and absorption components. By utilizing Voronoi binning, we obtained a comprehensive map of the kinematic properties of these components. These observations revealed the presence of a redshifted, high velocity (v ∼ 500 km s−1) bipolar structure of Lyα emission, most likely corresponding to an outflow of ionized gas. The outflow extends beyond the compact radio source on both sides, with a total size of ∼21 kpc. Its kinetic power (1042.1 erg s−1) is about five orders of magnitude smaller than its radio power. Additional ionized lines, including HeIIλ1640, CIVλ1550 and CIII]λ1908 were detected and their line flux ratios determined. The presence of HeII allowed for a precise redshift measurement (z = 2.945 ± 0.002). Along with the recent discovery of a similar structure in TN J1049−1258, another HzRG, it displays the feasibility of using Lyα as a tracer of outflowing gas in high redshift sources, and particularly so when supported by non-resonant ionized lines such as HeII, which allow for accurate redshift and velocity measurements

    [Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]

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    Newspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.

    Emerging drugs for the treatment of HIV/AIDS: a review of 2019/2020 phase II and III trials

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    Introduction: The study of emerging drug trials to treat people living with HIV (PLWH) helps to understand any advantages and disadvantages of therapies that will be available on the market in the short-term future as well as the mechanisms underlying a better cure. Areas covered: This review analyzes phase 2 and 3 clinical trials published between 2019 and 2020 concerning six different emerging drugs. The majority of the trials focus on long acting drugs, but also on new orally administered compounds. Expert opinion: The biggest news in antiretroviral therapy (ART) is the approval of cabotegravir/rilpivirine as a complete long-acting (LA) therapeutic regimen. It paves the way for an innovation that may change the paradigms of HIV treatment in the long term, albeit it will not be obvious to implement and treatment adherence still needs to be fully evaluated. Results of phase 3 Islatravir trials are awaited. Lenacapavir may soon reach phase 3. These drugs may pave the way for 6-month ART in the next future. Fostemsavir has been recently approved. Albuvirtide, a fusion inhibitor approved in China, presents several limitations for its intravenous use only. UB-421 and VRC01 are monoclonal antibodies against HIV. This emerging technology has shown interesting results but needs further studies
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