Quantum Locality

It is argued that while quantum mechanics contains nonlocal or entangled states, the instantaneous or nonlocal influences sometimes thought to be present due to violations of Bell inequalities in fact arise from mistaken attempts to apply classical concepts and introduce probabilities in a manner inconsistent with the Hilbert space structure of standard quantum mechanics. Instead, Einstein locality is a valid quantum principle: objective properties of individual quantum systems do not change when something is done to another noninteracting system. There is no reason to suspect any conflict between quantum theory and special relativity.Comment: Introduction has been revised, references added, minor corrections elsewhere. To appear in Foundations of Physic

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

Seaweed Paddock: Initial Modeling and Design for a Sargassum Ranch

This paper describes the “SeaweedPaddock” system to profitably grow and harvest open-ocean Sargassum sp. as a sustainable source of macroalgal biomass and biofuel. The US Department of Energy Advanced Research Projects Agency - Energy (ARPA-E) initiated the MacroAlgae Research Inspiring Novel Energy Research (MARINER) program to develop technologies to eventually sustainably harvest macroalgae at 80 per dry metric ton (DMT). The University of Southern Mississippi team is characterizing an unmoored SeaweedPaddock; analyses include tow speed and energy required to avoid hazards, farm design to minimize biomass loss, economical harvesting, and nutrient supply. Initial results indicate that nighttime “smart towing” could allow the SeaweedPaddock system to produce macroalgae at full scale at costs below the ARPA-E goal provided that Sargassum grows at sufficient rates during the day after having been confined all night in a moving fence and that sufficient nutrients are made available. Cost projections for a successful, intensive, scaled system could be competitive with current prices for fossil fuels

Water, Nitrogen and Ion Balance in the African Treefrog \u3cem\u3eChiromantis petersi\u3c/em\u3e Boulenger (Anura: Rhacophoridae), With Comments on the Structure of the Integument

Physiological and anatomical investigations were carried out on Chiromantis petersi, an African rhacophorid treefrog, with the following results: 1. The minimum rate of evaporative water loss (EWL) was 0.41±0.25 mg/g.h. 2. The maximum rate of water uptake in dehydrated frogs averaged 75% body weight/h in the first 10 min of rehydration. 3. The low EWL correlates with the unique structure of the chromatophore units of the dorsum, the sides and the gular region. 4. The high rates of water uptake correlate with the structure of the verrucae hydrophilica of the abdominal and femoral surfaces. These verrucae are not unique to this species. 5. When denied water and force-fed mealworms for 30 days, plasma osmotic concentrations increased from 210 mosM to 384 mosM, with Na+, Cl− and urea contributing most to the increase. 6. The ratio of urinary K+∶Na+ excretion is 3∶1. 7. Excretion totaled 155 mg N/kg·day with 97% as uric acid, 2% as ammonia and 1% as urea. 8. Since urea accumulated in the body at the rate of 58.5±6.1 mg N/kg·day, total nitrogen production was 213 mg N/kg·day. Uric acid formed 70% thereof. 9. Chiromantis petersi is capable of surviving without free water for prolonged periods and is as well adapted to its xeric environment as are many desert reptiles