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We present the second data release of the MeerKAT Absorption Line Survey (MALS), consisting of wideband continuum catalogues of 391 pointings observed at L band. The full wideband catalogue covers 4344 deg2 of sky, reaches a depth of 10 µJy beam−1, and contains 971 980 sources. With its balance between survey depth and sky coverage, MALS DR2 covers five orders of magnitude of flux density, presenting a robust view of the extragalactic radio source population down to 200 µJy. Using this catalogue, we perform a measurement of the cosmic radio dipole, an anisotropy in the number counts of radio sources with respect to the cosmic background, analogous to the dipole found in the cosmic microwave background (CMB). For this measurement, we present the characterisation of completeness and noise properties of the catalogue, and show that a declination-dependent systematic affects the number density of faint sources. In the dipole measurement on the MALS catalogue, we recover reasonable dipole measurements once we model the declination systematic with a linear fit between the size of the major axis of the restoring beam and the amount of sources of each pointing. The final results are consistent with the CMB dipole in terms of direction and amplitude, unlike many recent measurements of the cosmic radio dipole made with other centimetre wavelength catalogues, which generally show a significantly larger amplitude. This result demonstrates the value of dipole measurements with deeper and more sparse radio surveys, as the population of faint sources probed may have had a significant impact on the measured dipole. [ABSTRACT FROM AUTHOR]

We report on the discovery and localization of fast radio bursts (FRBs) from the MeerTRAP project, a commensal fast radio transient-detection programme at MeerKAT in South Africa. Our hybrid approach combines a coherent search with an average field-of-view (FoV) of 0.4  |$\rm deg^{2}$| with an incoherent search utilizing a FoV of ∼1.27  |$\rm deg^{2}$| (both at 1284 MHz). Here, we present results on the first three FRBs: FRB 20200413A (DM = 1990.05 pc cm−3), FRB 20200915A (DM = 740.65 pc cm−3), and FRB 20201123A (DM = 433.55 pc cm−3). FRB 20200413A was discovered only in the incoherent beam. FRB 20200915A (also discovered only in the incoherent beam) shows speckled emission in the dynamic spectrum, which cannot be explained by interstellar scintillation in our Galaxy or plasma lensing, and might be intrinsic to the source. FRB 20201123A shows a faint post-cursor burst of about 200 ms after the main burst and warrants further follow-up to confirm whether it is a repeating FRB. FRB 20201123A also exhibits significant temporal broadening, consistent with scattering, by a turbulent medium. The broadening exceeds from what is predicted for the medium along the sightline through our Galaxy. We associate this scattering with the turbulent medium in the environment of the FRB in the host galaxy. Within the approximately 1 arcmin localization region of FRB 20201123A, we identify one luminous galaxy (r ≈ 15.67; J173438.35-504550.4) that dominates the posterior probability for a host association. The galaxy's measured properties are consistent with other FRB hosts with secure associations. [ABSTRACT FROM AUTHOR]

We present details of the Automated Radio Telescope Imaging Pipeline (ARTIP) and the results of a sensitive blind search for H i and OH absorbers at z < 0.4 and z < 0.7, respectively. ARTIP is written in Python 3.6, extensively uses the Common Astronomy Software Application tools and tasks, and is designed to enable the geographically distributed MeerKAT Absorption Line Survey (MALS) team to collaboratively process large volumes of radio interferometric data. We apply it to the first MALS data set obtained using the 64-dish MeerKAT radio telescope and 32 K channel mode of the correlator. With merely 40 minutes on target, we present the most sensitive spectrum of PKS 1830-211 ever obtained and characterize the known H i (z = 0.19) and OH (z = 0.89) absorbers. We further demonstrate ARTIP 's capabilities to handle realistic observing scenarios by applying it to a sample of 72 bright radio sources observed with the upgraded Giant Metrewave Radio Telescope (uGMRT) to blindly search for H i and OH absorbers. We estimate the numbers of H i and OH absorbers per unit redshift to be n21(z ∼ 0.18) < 0.14 and nOH(z ∼ 0.40) < 0.12, respectively, and constrain the cold gas covering factor of galaxies at large impact parameters (50 kpc < ρ < 150 kpc) to be less than 0.022. Due to the small redshift path, Δz ∼ 13 for H i with column density >5.4 × 1019 cm−2, the survey has probed only the outskirts of star-forming galaxies at ρ > 30 kpc. MALS with the expected Δz ∼ 103–4 will overcome this limitation and provide stringent constraints on the cold gas fraction of galaxies in diverse environments over 0 < z < 1.5. [ABSTRACT FROM AUTHOR]

Ultrasteep spectrum (USS) radio sources are good tracers of powerful radio galaxies at z > 2. Identification of even a single bright radio galaxy at z > 6 can be used to detect redshifted 21 cm absorption due to neutral hydrogen in the intervening intergalactic medium. Here we describe a new sample of high-redshift radio galaxy (HzRG) candidates constructed from the TIFR GMRT Sky Survey First Alternative Data Release survey at 150 MHz. We employ USS selection (α ≤-1.3) in ~10 000 deg², in combination with strict size selection and non-detections in all-sky optical and infrared surveys. We apply flux density cuts that probe a unique parameter space in flux density (50mJy < S150 < 200 mJy) to build a sample of 32 HzRG candidates. Follow-up Karl G. Jansky Very Large Array (VLA) observations at 1.4 GHz with an average beam size of 1.3 arcsec revealed ~48 per cent of sources to have a single radio component. P-band (370 MHz) imaging of 17 of these sources revealed a flattening radio SED for 10 sources at low frequencies, which is expected from compact HzRGs. Two of our sources lie in fields where deeper multiwavelength photometry and ancillary radio data are available and for one of these we find a best-fitting photo-z of 4.8 ± 2.0. The other source has zphot = 1.4 ± 0.1 and a small angular size (3.7 arcsec), which could be associated with an obscured star-forming galaxy or with a 'dead' elliptical. One USS radio source not part of the HzRG sample but observed with the VLA none the less is revealed to be a candidate giant radio galaxy with a host galaxy photo-z of 1.8 ± 0.5, indicating a size of 875 kpc. [ABSTRACT FROM AUTHOR]

We describe an image-based method that uses two radio criteria, compactness, and spectral index, to identify promising pulsar candidates among Fermi Large Area Telescope (LAT) unassociated sources. These criteria are applied to those radio sources from the Giant Metrewave Radio Telescope all-sky survey at 150 MHz (TGSS ADR1) found within the error ellipses of unassociated sources from the 3FGL catalogue and a preliminary source list based on 7 yr of LAT data. After follow-up interferometric observations to identify extended or variable sources, a list of 16 compact, steep-spectrum candidates is generated. An ongoing search for pulsations in these candidates, in gamma rays and radio, has found 6 ms pulsars and one normal pulsar. A comparison of this method with existing selection criteria based on gamma-ray spectral and variability properties suggests that the pulsar discovery space using Fermi may be larger than previously thought. Radio imaging is a hitherto underutilized source selection method that can be used, as with other multiwavelength techniques, in the search for Fermi pulsars. [ABSTRACT FROM AUTHOR]

Dihydroartemisinin (DHA)-piperaquine is promising for malaria chemoprevention in pregnancy. We assessed the impacts of pregnancy and efavirenz-based antiretroviral therapy on exposure to DHA and piperaquine in pregnant Ugandan women. Intensive sampling was performed at 28 weeks gestation in 31 HIV-uninfected pregnant women, in 27 HIV-infected pregnant women receiving efavirenz, and in 30 HIV-uninfected nonpregnant women. DHA peak concentration and area under the concentration time curve (AUC0-8hr) were 50% and 47% lower, respectively, and piperaquine AUC0-21d was 40% lower in pregnant women compared to nonpregnant women. DHA AUC0-8hr and piperaquine AUC0-21d were 27% and 38% lower, respectively, in pregnant women receiving efavirenz compared to HIV-uninfected pregnant women. Exposure to DHA and piperaquine were lower among pregnant women and particularly in women on efavirenz, suggesting a need for dose modifications. The study of modified dosing strategies for these populations is urgently needed. [ABSTRACT FROM AUTHOR]

We present deep ALMA CO(5-4) observations of a main-sequence, clumpy galaxy at z = 1.5 in the HUDF. Thanks to the ∼0″.5 resolution of the ALMA data, we can link stellar population properties to the CO(5-4) emission on scales of a few kiloparsec. We detect strong CO(5-4) emission from the nuclear region of the galaxy, consistent with the observed LIR-L'CO(5-4) correlation and indicating ongoing nuclear star formation. The CO(5-4) gas component appears more concentrated than other star formation tracers or the dust distribution in this galaxy. We discuss possible implications of this difference in terms of star formation efficiency and mass build-up at the galaxy centre. Conversely, we do not detect any CO(5-4) emission from the UV-bright clumps. This might imply that clumps have a high star formation efficiency (although they do not display unusually high specific star formation rates) and are not entirely gas dominated, with gas fractions no larger than that of their host galaxy (∼50 per cent). Stellar feedback and disc instability torques funnelling gas towards the galaxy centre could contribute to the relatively low gas content. Alternatively, clumps could fall in a more standard star formation efficiency regime if their actual star formation rates are lower than generally assumed. We find that clump star formation rates derived with several different, plausible methods can vary by up to an order of magnitude. The lowest estimates would be compatible with a CO(5-4) non-detection even for main-sequence like values of star formation efficiency and gas content. [ABSTRACT FROM AUTHOR]

The Fermi Large Area Telescope has detected an extended region of GeV emission towards the Galactic Centre that is currently thought to be powered by dark matter annihilation or a population of young and/or millisecond pulsars. In a test of the pulsar hypothesis, we have carried out an initial search of a 20 deg2 area centred on the peak of the galactic centre GeV excess. Candidate pulsars were identified as a compact, steep spectrum continuum radio source on interferometric images and followed with targeted single-dish pulsation searches. We report the discovery of the recycled pulsar PSR 1751–2737 with a spin period of 2.23 ms. PSR 1751–2737 appears to be an isolated recycled pulsar located within the disc of our Galaxy, and it is not part of the putative bulge population of pulsars that are thought to be responsible for the excess GeV emission. However, our initial success in this small pilot survey suggests that this hybrid method (i.e. wide-field interferometric imaging followed up with single-dish pulsation searches) may be an efficient alternative strategy for testing whether a putative bulge population of pulsars is responsible for the GeV excess. [ABSTRACT FROM AUTHOR]

We report on a search for steep spectrum radio sources within the 95 per cent confidence error ellipses of the Fermi unassociated sources from the Large Area Telescope (LAT). Using existing catalogues and the newly released Giant Metrewave Radio Telescope all-sky survey at 150 MHz, we identify compact radio sources that are bright at MHz frequencies but faint or absent at GHz frequencies. Such steep spectrum radio sources are rare and constitute a sample of pulsar candidates, selected independently of period, dispersion measure, interstellar scattering and orbital parameters. We find point-like, steep spectrum candidates towards 11 Fermi sources. Based on the gamma-ray/radio positional coincidence, the rarity of such radio sources, and the properties of the 3FGL sources themselves, we argue that many of these sources could be pulsars. They may have been missed by previous radio periodicity searches due to interstellar propagation effects or because they lie in an unusually tight binary. If this hypothesis is correct, then renewed gamma-ray and radio periodicity searches at the positions of the steep spectrum radio sources may reveal pulsations. [ABSTRACT FROM AUTHOR]

A. Shubov, P. Jagannathan, P. V. Chin-Hong. Pantoea agglomerans pneumonia in a heart-lung transplant recipient: case report and a review of an emerging pathogen in immunocompromised hosts. Transpl Infect Dis 2011. All rights reserved Abstract: Pantoea agglomerans is a gram-negative rod that is frequently found on the exterior of many plants, fruits, vegetables, and in soil, and it is used as a biopesticide in the agriculture industry. Recent reports have implicated P. agglomerans in systemic infections of immunocompromised hosts and neonates, as well as more localized infections in healthy hosts. P. agglomerans as a cause of hospital-acquired pneumonia has not been well characterized. We report a case of P. agglomerans pneumonia in a heart-lung transplant recipient following transplantation. The organism was susceptible to multiple antimicrobial agents and treated successfully with ertapenem. We review the patient's course and the relevant literature, and discuss implications for the future. [ABSTRACT FROM AUTHOR]

In this work, it has been demonstrated that the disadvantages associated with the use of the potassium ferricyanide solution as the catholyte in a microbial fuel cell (MFC) were overcome by using a graphite cathode electrochemically modified with chromium hexacyanoferrate (CrHCF) film. The existing use of potassium ferricyanide solution as the catholyte is limited by the need to replace the catholyte every week and it cannot be used in a sustained manner. The present work evaluates the suitability of the CrHCF modified film as a suitable cathode material in a prototype of a MFC wherein Hansenula anomala is used as the biocatalyst in the anode compartment. The CrHCF film was prepared in the presence of the dopant camphor sulphonic acid to improve the reversibility of the film in phosphate buffer. [ABSTRACT FROM AUTHOR]

HIV has increasingly become an infection of poverty. Adequate HIV transmission knowledge among HIV-positive patients is necessary to reduce the risk of secondary infection and protect those who are uninfected from transmission. This study was conducted among individuals enrolled in a program that serves impoverished HIV patients in the Boston area. Although the mean HIV transmission knowledge score was 80% for this group, a significant proportion of patients demonstrated limitations in knowledge of HIV transmission. Highly vulnerable patients, such as those who reported not accessing HIV medications, a history of sexual abuse, or problems getting clothing, had lower levels of HIV knowledge. This paper hopes to alert providers that their most vulnerable patients may be at an increased risk of re-infection or transmission due to limited HIV knowledge. Programs that serve HIV-positive patients coping with poverty and other serious problems need to ensure adequate knowledge of HIV transmission to reduce the overall burden of HIV in resource-poor settings. [ABSTRACT FROM AUTHOR]

project selection method has been derived for the R&D Division of an electrical equipment manufacturer in a developing country. In the method, a scoring model is used to select and rank projects which have a wide range of objectives and characteristics. The criteria used for selection relate specifically to the organisation's needs and culture, and they are weighted according to their relative importance as perceived by executives. The results of the study indicate the research culture of the R&D Division and reflect its environment. As such the paper illustrates a methodology which can be universally applied to large R&D organisations in developing or developed countries. [ABSTRACT FROM AUTHOR]