SAR processing on the MPP

The processing of synthetic aperture radar (SAR) signals using the massively parallel processor (MPP) is discussed. The fast Fourier transform convolution procedures employed in the algorithms are described. The MPP architecture comprises an array unit (ARU) which processes arrays of data; an array control unit which controls the operation of the ARU and performs scalar arithmetic; a program and data management unit which controls the flow of data; and a unique staging memory (SM) which buffers and permutes data. The ARU contains a 128 by 128 array of bit-serial processing elements (PE). Two-by-four surarrays of PE's are packaged in a custom VLSI HCMOS chip. The staging memory is a large multidimensional-access memory which buffers and permutes data flowing with the system. Efficient SAR processing is achieved via ARU communication paths and SM data manipulation. Real time processing capability can be realized via a multiple ARU, multiple SM configuration

Receipt, 19 October 1870

https://egrove.olemiss.edu/aldrichdocs/1422/thumbnail.jp

A revision of the British Chronostratigraphy within the Last Glacial-Interglacial Cycle based on new evidence from Arclid, Cheshire UK

Of the 24 Greenland interstadials (GI) in the Last Glacial-interglacial cycle (LGIC) only five are conventionally recognised in Britain. This paper aims to improve understanding of the LGIC in Britain from a site at Arclid, Cheshire. Sediments were characterised and luminescence used to establish a chronology. This found that the Chelford Sand Formation spans 77-47 ka with sand deposited initially by aeolian but later by fluvial transportation. Coleoptera and Diptera from the basal peat lens provided a reconstruction for a heather-rich heathland environment grazed by large herbivores, with summer temperatures between 13-18° C, and winter temperatures between -14 and 1°C. Flies included the earliest records of the blood-sucking horsefly Haematopota pluvialis, and the soldierfly Chloromyia formosa. The overlying Stockport Sand Formation was deposited fluvioglacially between 47-41 ka with the upper Stockport Till formed by the advance of the last British icesheet after ~33 ka. Stenothermic beetle analysis from Arclid indicate similarities with results from other British mid LGIC sites, some of which are at or beyond the limit of radiocarbon dating and may be of a similar age to Arclid. Basal organic sediments found at Arclid along with other reassigned sites are proposed as a new Arclid Interstadial. A revised British LGIC chronostratigraphy has the Wretton, Chelford and Brimpton Interstadials and the previously suggested but not widely recognised Cassington Interstadial. The Arclid Interstadial occurred after these, but prior to the Upton Warren Interstadial complex. This closes the previous gap in interstadials between the Brimpton Interstadial and the Upton Warren Interstadial complex within the British chronostratigraphy

The practice of patient blood management among South African anaesthetic providers

A research report submitted to the Faculty of Health Sciences, in the partial fulfillment of the requirements for the degree of Master of Medicine in the branch of Anaesthesiology , School of Medicine, University of the Witwatersrand, Johannesburg, 2024Patient Blood Management (PBM) is a multidisciplinary and evidence-based approach aimed at optimising patient outcomes by effectively managing and preserving a patient's own blood, minimising unnecessary transfusions, and promoting overall blood conservation strategies. Thus far, perioperative PBM practices of South African anaesthetic providers have not been described. Methods This study prospectively evaluated perioperative PBM practices in South Africa utilising an online survey. In addition, we described the extent to which practices align to the national guidelines, the 2020 South African Society of Anaesthesiologists (SASA) guidelines, and 2014 South African National Blood Service (SANBS) guidelines. Results The information letter was opened 573 times. We received 403 surveys that were more than 50% complete and were included in this study. Most respondents were specialists (54.6%) or specialist trainees (25.1%) within their first five years of practice (54.6%). Most providers (89.3%) often or always record a preoperative haemoglobin. Only 1% of providers would defer elective surgery, other than caesarean section, if the haemoglobin (Hb) was 500 ml of blood loss is anticipated (21.2%), or in obstetric major haemorrhage (21.2%). In major haemorrhage, most respondents often or always monitor for, treat, and prevent hypothermia (97.5%), acidosis (96.0%), hypocalcaemia (90.0%), and hyperkalaemia (91.6%). Tranexamic acid is often or always used commonly in severe trauma (70.7%) and major obstetric haemorrhage (72.1%). Conclusions Overall, PBM practices were poor, and not in keeping with South African guidelines. The management of preoperative anaemia stands out as the most notable deficiency. Key points: Research question: What are the perioperative patient blood management (PBM) practices among South African anaesthetic providers? How do these practices align with the SASA and SANBS guidelines? Findings: Overall, PBM practices were poor, and not in keeping with South African guidelines. Meaning: Important context is provided for PBM in low- and middle-income countriesMM202