Springtails (Collembola) are wingless arthropods adapted to cutaneous respiration in temporarily rain-flooded habitats. They immediately form a plastron, protecting them against suffocation upon ...immersion into water and even low-surface-tension liquids such as alkanes. Recent experimental studies revealed a high-pressure resistance of such plastrons against collapse. In this work, skin sections of Orthonychiurus stachianus are studied by transmission electron microscopy. The micrographs reveal cavity side-wall profiles with characteristic overhangs. These were fitted by polynomials to allow access for analytical and numerical calculations of the breakthrough pressure, that is, the barrier against plastron collapse. Furthermore, model profiles with well-defined geometries were used to set the obtained results into context and to develop a general design principle for the most robust surface structures. Our results indicate the decisive role of the sectional profile of overhanging structures to form a robust heterogeneous wetting state for low-surface-tension liquids that enables the omniphobicity. Furthermore, the design principles of mushroom and serif T structures pave the way for omniphobic surfaces with a high-pressure resistance irrespective of solid surface chemistry.
The use of silver nanoparticle on various substrates has been widespread because of its good antibacterial properties that directly depend on the stability of the silver nanoparticles in a colloidal ...suspension. In this study, the colloidal solutions of the silver nanoparticles were synthesised by a simple and safe method by using lecithin as a stabilising agent and their stability was examined at various temperatures. The effect of the lecithin concentrations on the stability of the synthesised silver nanoparticles was examined from 25 to 80°C at 5°C intervals, by recording the changes in the UV–vis absorption spectra, the hydrodynamic diameter and the light scattering intensity of the silver nanoparticles. In addition, the morphology of the synthesised silver nanoparticles was investigated with the low-voltage scanning electron microscopy and transmission electron microscopy. The results indicated that increasing temperature caused different changes in the size of the stabilised and the unstabilised silver nanoparticles. The size of the stabilised silver nanoparticles reduced from 38 to 36 nm during increasing temperature, which confirmed good stability.
BACKGROUNDSevere bleeding under antithrombotic therapy is common and challenging in intensive care medicine; on the one hand, rapid bleeding control must be achieved and, on the other hand, ...thromboembolic complications must be avoided. AIMSThe paper will provide a brief overview of direct oral anticoagulants, therapeutic options and precise instructions for dealing with severe bleeding. RESULTSIn addition to general measures in direct oral anticoagulant (DOAC)-associated major bleeding, prothrombin complex concentrate (PCC), idarucizumab and andexanet alfa are available as specific antidote therapy. In case of bleeding under heparin therapy, protamine sulfate is available as a possible antidote. CONCLUSIONSIn particular, the importance of andexanet alfa in the treatment of factor Xa inhibitor-associated bleeding requires further investigation.
Zusammenfassung
Hintergrund
Schwere Blutungen unter antithrombotischer Therapie sind im intensivmedizinischen Alltag häufig und herausfordernd, einerseits muss eine rasche Blutungskontrolle erreicht ...werden, andererseits müssen thromboembolische Komplikationen vermieden werden.
Ziel der Arbeit
In dem Leitthemenbeitrag wird eine kurze Übersicht über die direkten oralen Antikoagulanzien, therapeutische Optionen und konkrete Handlungsanweisungen gegeben.
Ergebnisse
Neben Allgemeinmaßnahmen bei mit direkten oralen Antikoagulanzien (DOAK-)assoziierten Majorblutungen stehen im Wesentlichen Prothrombinkonzentrate (PPSB) und Idarucizumab als Antidottherapie zur Verfügung. Bei Blutungen unter Heparinen steht als mögliches Antidot Protaminsulfat zur Verfügung.
Schlussfolgerung
Insbesondere zum Stellenwert von Andexanet alfa in der Therapie von Faktor-Xa-Inhibitor-assoziierten Blutungen sind weitere Studien erforderlich.
Postmortem Examination of Patients With COVID-19 Schaller, Tina; Hirschbühl, Klaus; Burkhardt, Katrin ...
JAMA : the journal of the American Medical Association,
06/2020, Letnik:
323, Številka:
24
Journal Article
Recenzirano
Odprti dostop
This case series describes autopsy findings in 10 patients with proven severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection who died at a university medical center in Germany.
Waterproof and self-cleaning surfaces continue to attract much attention as they can be instrumental in various different technologies. Such surfaces are typically rough, allowing liquids to contact ...only the outermost tops of their asperities, with air being entrapped underneath. The formed solid–liquid–air interface is metastable and, hence, can be forced into a completely wetted solid surface. A detailed understanding of the wetting barrier and the dynamics of this transition is critically important for the practical use of the related surfaces. Toward this aim, wetting transitions were studied in situ at a set of patterned perfluoropolyether dimethacrylate (PFPEdma) polymer surfaces exhibiting surface features with different types of sidewall profiles. PFPEdma is intrinsically hydrophobic and exhibits a refractive index very similar to water. Upon immersion of the patterned surfaces into water, incident light was differently scattered at the solid–liquid–air and solid–liquid interface, which allows for distinguishing between both wetting states by dark-field microscopy. The wetting transition observed with this methodology was found to be determined by the sidewall profiles of the patterned structures. Partial recovery of the wetting was demonstrated to be induced by abrupt and continuous pressure reductions. A theoretical model based on Laplace’s law was developed and applied, allowing for the analytical calculation of the transition barrier and the potential to revert the wetting upon pressure reduction.
Abstract
Background and study aims
It is unclear if the clinical success rate of the over-the-scope-clip (OTSC) in peptic ulcer bleeding (PUB) is comparable when it is used in the first- or in the ...second-line of treatment.
Patients and methods
Data on endoscopic treatment (first- vs. second-line) in PUB with OTSC and clinical data were analyzed. The primary outcome was the clinical success of hemostasis, defined as the absence of recurrent bleeding or further intervention. Secondary outcomes were factors associated with OTSC failure.
Results
From April 2014 to March 2018, 100 patients (age 72 20 – 98 y, female 36 %) with PUB in the stomach or the duodenum were treated endoscopically with the OTSC. The OTSC was used as a first-line procedure (primary-OTSC) in 66 pts. Successful hemostasis could be achieved in 90.9 %. After failure of an initial endoscopic treatment, 34 patients were treated with the OTSC (secondary-OTSC) and the treatment was successful in 94.1 %. Recurrent bleeding occurred in n = 10 for primary-OTSC (16.7 %) and in n = 7 pts in the secondary-OTSC (21.9 %) (
P
= 0.81). Clinical success in the primary-OTSC was 75.8 % and 73.5 % in the secondary-OTSC respectively.
Conclusions
The OTSC has a high rate of initial bleeding control in first- and second line treatment of PUB. OTSC failure occurs more often in the duodenum than in the stomach and results in longer intensive care unit stay, higher amount of transfusions, and a higher reimbursement per case.
Zusammenfassung
Eine intraabdominelle Hypertension (IAH) ist ein häufiges Phänomen bei kritisch kranken Patienten und ist als ein anhaltender intraabdomineller Druck (IAP) ≥ 12 mm Hg definiert. Ein ...abdominelles Kompartmentsyndrom (ACS) ist definiert als eine IAP mit einem anhaltenden Druck ≥ 20 mm Hg in Zusammenschau mit einem neu aufgetretenen Organversagen. Als Surrogatparameter für die IAP dient der Blasendruck, der standardisiert nichtinvasiv gemessen werden sollte. Eine nicht erkannte und nicht therapierte IAH verschlechtert die Prognose des kritisch kranken Patienten.
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