Search for gravitational waves associated with gamma-ray bursts detected by Fermi and Swift during the LIGO–Virgo run O3b

We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC–2020 March 27 17:00 UTC). We conduct two independent searches: a generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds no evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate

171 Developing & Centralising a Nurse-Led Local Anaesthetic (La) Transperineal (Tp) Biopsy Service During Covid: A Success Story

INTRODUCTION: During the first COVID-19 wave, the BAUS Section of Oncology issued guidance to minimise risks of sepsis and general anaesthesia at prostate biopsy. Consequently, and as a result of diminished diagnostics capacity on Trust acute sites, we implemented a centralised network-wide nurse-led LA TP biopsy service on a COVID-secure “green” site and abandoned trans-rectal biopsies. We evaluated the impact of this service improvement on patient waiting times before and after national lockdown in March 2020. METHOD: Classic Quality Improvement (QI) methodology was used with continuous data collection and waiting list management by clinical staff with standard admin support. Balancing measurements were collected. Run charts were used to confirm whether a change led to a real and sustainable improvement. RESULTS: The number of days waiting, from time of request to date of biopsy, is presented in the following run chart. The mean waiting time for those pre lockdown was 145 days (SD 57) whereas post lockdown was 23 days (SD 20). This identified that there was a significant difference between the average waiting time pre and post lockdown (U = 55.5, p = <0.001) There were also reductions in waiting time when subcategorised into planned Active Surveillance cases, target cases and delayed cases. CONCLUSIONS: Centralising the TP biopsy service and converting to a nurse led LA service has led to reductions in waiting lists and was safely expedited and resilient even in the COVID-19 pandemic. Allowing a second advanced TP practitioner to be fully trained, during COVID. The service was highly valued by patients and staff

Superabsorbent aerogels from cellulose nanofibril hydrogels

Abstract Deep eutectic solvents (DESs) are promising green chemicals that can function as solvents, reagents, and catalysts in many applications because of their biodegradability, ready availability, and low toxicity. Here, a DES of choline chloride–urea was used as a non-hydrolytic pretreatment medium to obtain cellulose nanofibril (CNF) hydrogels from recycled cellulose pulps (boxboard, milk containerboard, and fluting) and virgin birch cellulose pulp using a mechanical Masuko grinder. The mechanical disintegration of DES-pretreated cellulose fibers resulted in highly viscous, gel-like cellulose nanofibril hydrogels with shear thinning behavior. According to transmission electron microscope (TEM) imaging, the nanofibrils had widths from 2 to 80 nm, possessed the initial cellulose I crystalline structure, and had a crystallinity index of 53–56%. The nanofibril hydrogels obtained were further used to produce low-cost, ultralight, highly porous, hydrophobic, and reusable superabsorbing aerogels that were used as efficient sponges to absorb oil and chemicals. The nanofibril sponges prepared by the consequent hydrophobic modification (silylation) of CNF hydrogels and freeze-drying had ultralow density (0.003 g/cm³) and high porosity (up to 99.8%). The sponges exhibited excellent oil/water absorption selectivity and ultrahigh oil (marine diesel oil, kerosene, gasoline, motor oil, castor oil, or linseed oil) and organic solvent (dimethyl sulfoxide, chloroform, n-hexane, toluene, acetone, or ethanol) absorption capacity. The nanofibril aerogels showed particular selectivity for marine diesel oil absorption from an oil–water mixture and possessed ultrahigh absorption capacities of up to 143 g/g, which were much higher than the commercial absorbent materials (i.e., polypropylenes) (9–27 g/g) used as references. Additionally, the absorbed oil could be recovered by means of simple mechanical squeezing, and the superabsorbent could be reused for at least 30 cycles

Observation of Gravitational Waves from the Coalescence of a 2.5–4.5 M _⊙ Compact Object and a Neutron Star

Abstract We report the observation of a coalescing compact binary with component masses 2.5–4.5 M ⊙ and 1.2–2.0 M ⊙ (all measurements quoted at the 90% credible level). The gravitational-wave signal GW230529_181500 was observed during the fourth observing run of the LIGO–Virgo–KAGRA detector network on 2023 May 29 by the LIGO Livingston observatory. The primary component of the source has a mass less than 5 M ⊙ at 99% credibility. We cannot definitively determine from gravitational-wave data alone whether either component of the source is a neutron star or a black hole. However, given existing estimates of the maximum neutron star mass, we find the most probable interpretation of the source to be the coalescence of a neutron star with a black hole that has a mass between the most massive neutron stars and the least massive black holes observed in the Galaxy. We provisionally estimate a merger rate density of 55 − 47 + 127 Gpc − 3 yr − 1 for compact binary coalescences with properties similar to the source of GW230529_181500; assuming that the source is a neutron star–black hole merger, GW230529_181500-like sources may make up the majority of neutron star–black hole coalescences. The discovery of this system implies an increase in the expected rate of neutron star–black hole mergers with electromagnetic counterparts and provides further evidence for compact objects existing within the purported lower mass gap.</jats:p