Search

We present a sensitive search with the Karl G. Jansky Very Large Array (VLA) for the radio counterpart of the gravitational wave candidate S191216ap, classified as a binary black hole merger, and suggested to be a possible multi-messenger event, based on the detection of a high energy neutrino and a TeV photon. We carried out a blind search at C band (4-8 GHz) over 0.3 deg² of the gamma-ray counterpart of S191216ap reported by the High-Altitude Water Cherenkov Observatory (HAWC). Our search, spanning three epochs over 130 days post-merger and having mean source-detection threshold of 75μJy/beam (4σ), yielded 5 variable sources associated with AGN activity and no definitive counterpart of S191216ap. We find <2% (3.0±1.3%) of the persistent radio sources at 6 GHz to be variable on a timescale of <1 week (week--months), consistent with previous radio variability studies. Our 4σ radio luminosity upper limit of ∼1.2×10²⁸ erg s⁻¹ Hz⁻¹ on the afterglow of S191216ap, within the HAWC error region, is 5-10 times deeper than previous BBH radio afterglow searches. Comparing this upper limit with theoretical expectations given by Perna et al. for putative jets launched by BBH mergers, for on-axis jets having energy ≃10⁴⁹ erg, we can rule out jet opening angles ≲20 degrees (assuming that the counterpart lies within the 1σ HAWC region that we observed).

We present a sensitive search with the Karl G. Jansky Very Large Array (VLA) for the radio counterpart of the gravitational wave candidate S191216ap, classified as a binary black hole merger, and suggested to be a possible multi-messenger event, based on the detection of a high energy neutrino and a TeV photon. We carried out a blind search at C band (4--8 GHz) over 0.3 deg$^2$ of the gamma-ray counterpart of S191216ap reported by the High-Altitude Water Cherenkov Observatory (HAWC). Our search, spanning three epochs over 130 days post-merger and having mean source-detection threshold of 75$\mu$Jy/beam (4$\sigma$), yielded 5 variable sources associated with AGN activity and no definitive counterpart of S191216ap. We find $<$2\% ($3.0\pm1.3$\%) of the persistent radio sources at 6 GHz to be variable on a timescale of $<$1 week (week--months), consistent with previous radio variability studies. Our 4$\sigma$ radio luminosity upper limit of $\sim$1.2$\times{10}^{28}$ erg s$^{-1}$ Hz$^{-1}$ on the afterglow of S191216ap, within the HAWC error region, is 5--10 times deeper than previous BBH radio afterglow searches. Comparing this upper limit with theoretical expectations given by \citeauthor{Perna2019} for putative jets launched by BBH mergers, for on-axis jets having energy $\simeq10^{49}$ erg, we can rule out jet opening angles $\lesssim$20 degrees (assuming that the counterpart lies within the 1$\sigma$ HAWC region that we observed)., Comment: 9 pages, 5 figures, 2 tables, submitted to ApJ

Item does not contain fulltext, Purpose of review: Myotonic dystrophy type 1 (DM1) is a severe, progressive genetic disease that affects between 1 in 3,000 and 8,000 individuals globally. No evidence-based guideline exists to inform the care of these patients, and most do not have access to multidisciplinary care centers staffed by experienced professionals, creating a clinical care deficit. Recent findings: The Myotonic Dystrophy Foundation (MDF) recruited 66 international clinicians experienced in DM1 patient care to develop consensus-based care recommendations. MDF created a 2-step methodology for the project using elements of the Single Text Procedure and the Nominal Group Technique. The process generated a 4-page Quick Reference Guide and a comprehensive, 55-page document that provides clinical care recommendations for 19 discrete body systems and/or care considerations. Summary: The resulting recommendations are intended to help standardize and elevate care for this patient population and reduce variability in clinical trial and study environments.

Item does not contain fulltext, Purpose of review: Myotonic dystrophy type 1 (DM1) is a severe, progressive genetic disease that affects between 1 in 3,000 and 8,000 individuals globally. No evidence-based guideline exists to inform the care of these patients, and most do not have access to multidisciplinary care centers staffed by experienced professionals, creating a clinical care deficit. Recent findings: The Myotonic Dystrophy Foundation (MDF) recruited 66 international clinicians experienced in DM1 patient care to develop consensus-based care recommendations. MDF created a 2-step methodology for the project using elements of the Single Text Procedure and the Nominal Group Technique. The process generated a 4-page Quick Reference Guide and a comprehensive, 55-page document that provides clinical care recommendations for 19 discrete body systems and/or care considerations. Summary: The resulting recommendations are intended to help standardize and elevate care for this patient population and reduce variability in clinical trial and study environments.

The Fermi Large Area Telescope has detected an extended region of GeV emission toward the Galactic Center 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 deg**2 area centered on the peak of the galactic center 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 disk 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., Comment: MNRAS, in press

The Fermi Large Area Telescope has detected an extended region of GeV emission toward the Galactic Center 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 deg**2 area centered on the peak of the galactic center 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 disk 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., Comment: MNRAS, in press

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.

One of the hallmarks of malignant cell populations is the ability to undergo continuous proliferation. This property allows clonal lineages to acquire sequential aberrations that can fuel increasingly autonomous growth, invasiveness, and therapeutic resistance. Innate cellular mechanisms have evolved to regulate replicative potential as a hedge against malignant progression. When activated in the absence of normal terminal differentiation cues, these mechanisms can result in a state of persistent cytostasis. This state, termed "senescence," can be triggered by intrinsic cellular processes such as telomere dysfunction and oncogene expression, and by exogenous factors such as DNA damaging agents or oxidative environments. Despite differences in upstream signaling, senescence often involves convergent interdependent activation of tumor suppressors p53 and p16/pRB, but can be induced, albeit with reduced sensitivity, when these suppressors are compromised. Doses of conventional genotoxic drugs required to achieve cancer cell senescence are often much lower than doses required to achieve outright cell death. Additional therapies, such as those targeting cyclin dependent kinases or components of the PI3K signaling pathway, may induce senescence specifically in cancer cells by circumventing defects in tumor suppressor pathways or exploiting cancer cells' heightened requirements for telomerase. Such treatments sufficient to induce cancer cell senescence could provide increased patient survival with fewer and less severe side effects than conventional cytotoxic regimens. This positive aspect is countered by important caveats regarding senescence reversibility, genomic instability, and paracrine effects that may increase heterogeneity and adaptive resistance of surviving cancer cells. Nevertheless, agents that effectively disrupt replicative immortality will likely be valuable components of new combinatorial approaches to cancer therapy.