Extremely low long‐term erosion rates around the Gamburtsev Mountains in interior East Antarctica

The high elevation and rugged relief (>3 km) of the Gamburtsev Subglacial Mountains (GSM) have long been considered enigmatic. Orogenesis normally occurs near plate boundaries, not cratonic interiors, and large‐scale tectonic activity last occurred in East Antarctica during the Pan‐African (480–600 Ma). We sampled detrital apatite from Eocene sands in Prydz Bay at the terminus of the Lambert Graben, which drained a large pre‐glacial basin including the northern Gamburtsev Mountains. Apatite fission‐track and (U‐Th)/He cooling ages constrain bedrock erosion rates throughout the catchment. We double‐dated apatites to resolve individual cooling histories. Erosion was very slow, averaging 0.01–0.02 km/Myr for >250 Myr, supporting the preservation of high elevation in interior East Antarctica since at least the cessation of Permian rifting. Long‐term topographic preservation lends credence to postulated high‐elevation mountain ice caps in East Antarctica since at least the Cretaceous and to the idea that cold‐based glaciation can preserve tectonically inactive topography

Local free-fall temperature of a RN-AdS black hole

We use the global embedding Minkowski space (GEMS) geometries of a (3+1)-dimensional curved Reissner-Nordstr\"om(RN)-AdS black hole spacetime into a (5+2)-dimensional flat spacetime to define a proper local temperature, which remains finite at the event horizon, for freely falling observers outside a static black hole. Our extended results include the known limiting cases of the RN, Schwarzschild--AdS, and Schwarzschild black holes.Comment: 18 pages, 11 figures, version to appear in Int. J. Mod. Phys.

Emergence of patterns in driven and in autonomous spatiotemporal systems

The relationship between a driven extended system and an autonomous spatiotemporal system is investigated in the context of coupled map lattice models. Specifically, a locally coupled map lattice subjected to an external drive is compared to a coupled map system with similar local couplings plus a global interaction. It is shown that, under some conditions, the emergent patterns in both systems are analogous. Based on the knowledge of the dynamical responses of the driven lattice, we present a method that allows the prediction of parameter values for the emergence of ordered spatiotemporal patterns in a class of coupled map systems having local coupling and general forms of global interactions.Comment: 7 pages, 3 figs, submitted to PRE (2002

Is convalescent plasma futile in COVID-19?:A Bayesian re-analysis of the RECOVERY randomized controlled trial

Background: Randomized trials are generally performed from a frequentist perspective, which can conflate absence of evidence with evidence of absence. The RECOVERY trial evaluated convalescent plasma for patients hospitalized with coronavirus disease 2019 (COVID-19) and concluded that there was no evidence of an effect. Re-analysis from a Bayesian perspective is warranted. Methods: Outcome data were extracted from the RECOVERY trial by serostatus and time of presentation. A Bayesian re-analysis with a wide variety of priors (vague, optimistic, sceptical, and pessimistic) was performed, calculating the posterior probability for: any benefit, an absolute risk difference of 0.5% (small benefit, number needed to treat 200), and an absolute risk difference of one percentage point (modest benefit, number needed to treat 100). Results: Across all patients, when analysed with a vague prior, the likelihood of any benefit or a modest benefit with convalescent plasma was estimated to be 64% and 18%, respectively. The estimated chance of any benefit was 95% if presenting within 7 days of symptoms, or 17% if presenting after this. In patients without a detectable antibody response at presentation, the chance of any benefit was 85%. However, it was only 20% in patients with a detectable antibody response at presentation. Conclusions: Bayesian re-analysis suggests that convalescent plasma reduces mortality by at least one percentage point among the 39% of patients who present within 7 days of symptoms, and that there is a 67% chance of the same mortality reduction in the 38% who are seronegative at the time of presentation. This is in contrast to the results in people who already have antibodies when they present. This biologically plausible finding bears witness to the advantage of Bayesian analyses over misuse of hypothesis tests to inform decisions

Algenteeltsystemen voor de tuinbouw: Integratie

de productie van algen biedt perspectief voor Nederlandse tuinbouwondernemers. Uit algen kunnen hoogwaardige producten worden gemaakt zoals voer voor vissen en mosselen, of stoffen als voedingssupplementen, eiwitten, vetzuren, pigmenten en antioxidanten. Algen kunnen worden geteeld in combinatie met traditionele tuinbouwgewassen, maar kunnen wellicht ook een alternatief gewas zijn voor telers. De overeenkomsten van algen teeltsystemen met teeltsystemen voor tuinbouwgewassen zijn vanuit een ontwerpoogpunt groot: algen hebben licht, water en nutriënten, CO2 en een optimaal klimaat nodig om te kunnen groeien met een goede kwaliteit. Tuinbouwondernemers hebben veel ervaring om de teeltcondities van hun huidige gewassen optimaal te sturen, ze hebben ervaring met klimaatregeling, CO2 dosering, water- en nutriëntenvoorziening en waterbehandelingssystemen. Het ligt voor de hand om deze ervaring te benutten voor de teelt van algen. Ze weten op een duurzame manier gewassen te telen. Hun bedrijf beschikt bovendien over de infrastructuur voor energievoorziening, waterbehandeling en CO2 voorziening. Er zijn synergie-effecten tussen gewas- en algenproductie op een tuinbouwbedrijf. In dit project wordt met behulp van modelberekeningen, metingen in algensystemen en op tuinbouwbedrijven en het opzetten van een nieuwe proeffaciliteit voor algen in de tuinbouw strategisch inzicht verkregen naar een geschikt teeltsysteem voor de teelt van hoogwaardige algen in combinatie met tuinbouwproductie in de toekomst

Prospective reporting of statistical analysis plans for randomised controlled trials

In 2017, JAMA published a statistical analysis plan (SAP) guidance document for randomised clinical trials (RCTs). This guidance is part of the EQUATOR Network of reporting resources and includes a checklist of minimum items for reporting details of statistical analysis of RCTs [1]. While the clinical trial protocol should describe the principal features of the statistical analysis, a separate detailed SAP containing sufficient information to support replication by an independent statistician may be needed [2,3,4]

Perioperative supplementation with a fruit and vegetable juice powder concentrate and postsurgical morbidity: a double-blind, randomised, placebo controlled clinical trial

Aims Surgical trauma leads to an inflammatory response that causes surgical morbidity. Reduced antioxidant micronutrient (AM)a levels and/or excessive levels of Reactive Oxygen Species (ROS)b have previously been linked to delayed wound healing and presence of chronic wounds. We aimed to evaluate the effect of pre-operative supplementation with encapsulated fruit and vegetable juice powder concentrate (JuicePlus+®) on postoperative morbidity and Quality of Life (QoL)c. Methods We conducted a randomised, double-blind, placebo-controlled two-arm parallel clinical trial evaluating postoperative morbidity following lower third molar surgery. Patients aged between 18 and 65 years were randomised to take verum or placebo for 10 weeks prior to surgery and during the first postoperative week. The primary endpoint was the between-group difference in QoL over the first postoperative week, with secondary endpoints being related to other measures of postoperative morbidity (pain and trismus). Results One-hundred and eighty-three out of 238 randomised patients received surgery (Intention-To-Treat population). Postoperative QoL tended to be higher in the active compared to the placebo group (p=0.059). Furthermore, reduction in mouth opening 2 days after surgery was 3.1 mm smaller (p=0.042), the mean pain score over the postoperative week was 9.4 mm lower (p=0.007) and patients were less likely to experience moderate to severe pain on postoperative day 2 (RR 0.58, p=0.030), comparing verum to placebo groups. Conclusion Pre-operative supplementation with a fruit and vegetable supplement rich in AM may improve postoperative QoL and reduce surgical morbidity and post-operative complications after surgery

Algenteeltsystemen voor de tuinbouw II : op weg naar opschaling

De productie van hoogwaardige stoffen zoals kleurstoffen of voedingssupplementen uit algen biedt perspectief voor Nederlandse tuinbouwondernemers. Tuinbouwondernemers hebben veel ervaring om de teeltcondities van hun huidige gewassen door klimaatregeling, CO2 dosering, water- en nutriënten voorziening optimaal te sturen voor een hoogwaardig eindproduct. Ze hebben ervaring met de productie van voedingsmiddelen en om aan de daaraan gestelde kwaliteitseisen te voldoen en logistiek en afzet te organiseren. Het ligt voor de hand om deze ervaring te benutten voor de teelt van algen en hiermee nieuwe duurzame producten te leveren en bij te dragen aan de biobased economy. In dit project is experimenteel onderzoek uitgevoerd naar de invloed van verschillende teeltfactoren op de algenproductie in een nieuwe proeffaciliteit met buisvormige algenreactoren in kassen in Bleiswijk. Daarnaast zijn in dit project economische getallen van investerings- en exploitatiekosten verzameld en is er een economisch rekenmodel ontwikkeld om een realistisch perspectief van algenteelt in kassen in schetsen. Hiermee wordt nieuw strategisch inzicht verkregen wat een geschikt teeltsysteem voor de teelt van hoogwaardige algen in combinatie met tuinbouwproductie op grote schaal in de toekomst is