Search

Abstract Background Although life-saving in selected patients, ECMO treatment still has high mortality which for a large part is due to treatment-related complications. A feared complication is ischemic stroke for which heparin is routinely administered for which the dosage is usually guided by activated partial thromboplastin time (aPTT). However, there is no relation between aPTT and the rare occurrence of ischemic stroke (1.2%), but there is a relation with the much more frequent occurrence of bleeding complications (55%) and blood transfusion. Both are strongly related to outcome. Methods We will conduct a three-arm non-inferiority randomized controlled trial, in adult patients treated with ECMO. Participants will be randomized between heparin administration with a target of 2–2.5 times baseline aPTT, 1.5–2 times baseline aPTT, or low molecular weight heparin guided by weight and renal function. Apart from anticoagulation targets, treatment will be according to standard care. The primary outcome parameter is a combined endpoint consisting of major bleeding including hemorrhagic stroke, severe thromboembolic complications including ischemic stroke, and mortality at 6 months. Discussion We hypothesize that with lower anticoagulation targets or anticoagulation with LMWH during ECMO therapy, patients will have fewer hemorrhagic complications without an increase in thromboembolic complication or a negative effect on their outcome. If our hypothesis is confirmed, this study could lead to a change in anticoagulation protocols and a better outcome for patients treated with ECMO. Trial registration ClinicalTrials.gov NCT04536272 . Registered on 2 September 2020. Netherlands Trial Register NL7969

Large tropical trees are rightly perceived as supporting a plethora of organisms. However, baseline data about the variety of taxa coexisting on single large tropical trees are lacking and prevent a full understanding of both the magnitude of biodiversity and the complexity of interactions among organisms in tropical rainforests. The two main aims of the research program "Life on Trees" (LOT) are (1) to establish baseline knowledge on the number of eukaryote species supported/hosted by the above-ground part of a single tropical tree and (2) to understand how these communities of organisms are assembled and distributed on or inside the tree. To achieve the first goal, we integrated a set of 36 methods for comprehensively sampling eukaryotes (plants, fungi, animals, protists) present on a tropical tree. The resulting LOT protocol was conceived and implemented during projects in the Andean Amazon region and is proposed here as a guideline for future projects of a similar nature. To address the second objective, we evaluated the microclimatic differences between tree zones and tested state-of-the-art terrestrial laser scanning (TLS) and positioning technologies incorporating satellite and fixed base station signals (dGNSS). A marked variation in temperature and relative humidity was detected along a 6-zones Johansson scheme, a tree structure subdivision system commonly used to study the stratification of epiphytic plants. Samples were collected from these six zones, including three along the trunk and three in the canopy. To better understand how different tree components (e.g., bark, leaves, fruits, flowers, dead wood) contribute to overall tree biodiversity, we categorized observations into communities based on Johansson zones and microhabitats. TLS was an essential aid in understanding the complex tree architecture. By contrast, the accuracy of positioning samples in the tree with dGNSS was low. Comprehensively sampling the biota of individual trees offers an alternative to assessing the biodiversity of fewer groups of organisms at the forest scale. Large old tropical trees provide a wealth of microhabitats that encompass a wide range of ecological conditions, thereby capturing a broad spectrum of biodiversity. [ABSTRACT FROM AUTHOR]

Measurements of ion speed in the plume of a pulsed high-current vacuum arc thruster were performed by means of electrostatic probes. The probes were designed to provide direct speed measurements with minimum disturbance on the plasma jet. Typical mean values of vi for Ti and Cu cathodes are determined at different locations downstream of the electrodes, in the far field region. From one VAT discharge to another, the mean ion speed strongly varies which leads to a large statistical dispersion. Single-shot analysis allows the observation of the plume anisotropy and its high divergence as well as the existence of several ion groups of different speeds throughout a discharge.

En un contexto de crisis socio-ambiental en el cual se tiene como meta mitigar el calentamiento global, a la vez de democratizar y alcanzar seguridad energética, la energía solar fotovoltaica genera grandes expectativas por sus posibilidades de adaptación en contextos urbanos, mediante la aplicación e integración en el sector edilicio. En este marco, el presente trabajo tiene por objeto realizar una propuesta de diseño sustentado en la introducción de la tecnología solar fotovoltaica en un edificio residencial de la Ciudad de San Juan – Argentina, conforme a sus características morfológicas arquitectónica y urbana. Para ello se emplea el software SketchUp con el cual se diseña dicha propuesta y el System Advisor Model que determina su potencial de generación y, producto del autoconsumo, el ahorro energético y económico resultante. Se concluye que es posible alcanzar una generación de energía equivalente al 44% del consumo anual, aun cuando el edificio presenta condicionantes por no haber incluido dicha variable de análisis en el diseño.

Blood purification as an adjunctive therapy has been studied for several decades. In this review, we will focus on the most recent studies, particularly on adsorption techniques. These include hemofilters with adsorptive membranes, both endotoxin-specific and non-specific. In addition, we will discuss sorbents that target endotoxins, as well as devices that non-selectively capture viruses and bacteria. For each technique, we will also explore the reasons why blood purification methods have thus far failed to improve survival. Conventionally, reasons for the lack of success in blood purification techniques have been attributed to the need for better patient stratification through bedside measurements of interleukins and endotoxins. The choice of assay is also crucial, with endotoxin activity assays being preferable to other forms of limulus amoebocyte lysate assays. Another critical factor is timing, as administering blood purification at the wrong moment can potentially harm the patient. Mechanistic studies are still lacking for most devices, leaving us to treat patients blindly, except in endotoxin cases. In the context of viruses, especially COVID-19, we require a deeper understanding of the complexities involved in viral replication, as this could significantly impact the efficacy of blood purification techniques. The failures highlighted for each device should be viewed as potential areas for improvement. Despite the challenges, we remain hopeful that these techniques will eventually succeed and prove beneficial in the future.