Changes in ambient air quality and atmospheric composition and reactivity in the South East of the UK as a result of the COVID-19 lockdown.

The COVID-19 pandemic forced governments around the world to impose restrictions on daily life to prevent the spread of the virus. This resulted in unprecedented reductions in anthropogenic activity, and reduced emissions of certain air pollutants, namely oxides of nitrogen. The UK 'lockdown' was enforced on 23/03/2020, which led to restrictions on movement, social interaction, and 'non-essential' businesses and services. This study employed an ensemble of measurement and modelling techniques to investigate changes in air quality, atmospheric composition and boundary layer reactivity in the South East of the UK post-lockdown. The techniques employed included in-situ gas- and particle-phase monitoring within central and local authority air quality monitoring networks, remote sensing by long path Differential Optical Absorption Spectroscopy and Sentinel-5P's TROPOMI, and detailed 0-D chemical box modelling. Findings showed that de-trended NO2 concentrations decreased by an average of 14-38% when compared to the mean of the same period over the preceding 5-years. We found that de-trended particulate matter concentrations had been influenced by interregional pollution episodes, and de-trended ozone concentrations had increased across most sites, by up to 15%, such that total Ox levels were roughly preserved. 0-D chemical box model simulations showed the observed increases in ozone concentrations during lockdown under the hydrocarbon-limited ozone production regime, where total NOx decreased proportionally greater than total non-methane hydrocarbons, which led to an increase in total hydroxyl, peroxy and organic peroxy radicals. These findings suggest a more complex scenario in terms of changes in air quality owing to the COVID-19 lockdown than originally reported and provide a window into the future to illustrate potential outcomes of policy interventions seeking large-scale NOx emissions reductions without due consideration of other reactive trace species.

Red cell damage after pumping by two infusion control devices (Arcomed VP 7000 and IVAC 572).

The aim of this study was to assess the performance in terms of red cell damage of two peristaltic volumetric infusion pumps - the Alaris IVAC 572 (San Diego, CA, USA) and Arcomed Volumed VP7000 (Regensdorf, Switzerland). Various infusion pumps are available to transfuse blood at a predetermined rate. It is recommended that each machine should be individually assessed. This experiment used six units of single-donor-transfusable packed red cells and ran each unit through both pumps. This was carried out at 9, 28 and 35 days post-donation at rates from 2 to 150 mL h(-1). Post-pumping samples from these experiments, and a pre-pumping sample in each case, were analysed for levels of potassium and free haemoglobin (Hb). They were also examined microscopically for evidence of cell damage. Potassium levels showed no significant change with pumping on any occasion, but rose significantly as the samples aged. Free Hb showed some variation, but the only consistent finding was a similar rise in value with increasing pack age. Microscopic examination revealed no cell damage under any condition. Both pumps performed to an acceptable level and appear safe to be used for red cell transfusion.

Radical prostatectomy in the presence of pelvic lipomatosis.

Pelvic lipomatosis may increase significantly the difficulty and morbidity of many urologic procedures. Radical prostatectomy in this setting has not been described previously. Such a case is presented and the reported surgical experience in pelvic lipomatosis is reviewed. Considerations in the management of prostatic cancer in patients with this condition are discussed.

Accuracy of staging in A1 carcinoma of the prostate.

The classification of patients with incidental carcinoma of the prostate into focal (Stage A1) or diffuse (Stage A2) subgroups depends primarily on the microscopic findings on tissue removed from transurethral resection (TUR) or open enucleation. However, these procedures sample only a portion of the entire prostate, and some patients staged A1 may have residual diffuse cancer that should properly be classified as Stage A2. This study is a review of 86 patients with Stage A1 cancer of the prostate in whom additional prostatic tissue was available because of repeat transurethral resection or radical prostatectomy. Only six patients (7%) were found to have diffuse cancer in the remaining prostatic tissue. Therefore, it appears that the classification of patients into Stage A1 or Stage A2 is generally accurate when based on the findings from initial TUR alone and that the incidence of understaging in this group is low. Repeat transurethral resection does not appear to contribute significantly to the accuracy of staging.

Surgical treatment of stage A2 prostatic carcinoma: significance of tumor grade and extent.

Patients with stage A2 carcinoma of the prostate are a heterogeneous population and not all of them progress to clinically manifest disease. We found a similar variability in terms of the pathological findings in a group of 34 patients with stage A2 disease undergoing pelvic lymphadenectomy and radical prostatectomy. While 8 patients (24 per cent) had metastatic disease on staging lymphadenectomy, 9 patients (27 per cent) had negative lymphadenectomy, with minimal or no residual tumor in the radical specimen. The histologic grade and extent of tumor on transurethral resection did not predict reliably patients with stage A2 disease and minimally invasive cancer at radical prostatectomy. It appears that present criteria for separating stage A tumors into focal and diffuse categories are adequate for selecting therapy for patients with incidental carcinoma of the prostate.