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Synchrotron x-ray diffraction has been used to study the surface and the interior hexatic-to-liquid (smectic-I to smectic-C) melting transitions of freely suspended liquid-crystal films of N-[4'-(n-heptyl)benzylidene]-4-(n-heptyl)aniline (7O.7) five molecular layers thick. Both the surface hexatic monolayers and the interior hexatic layers melt via hysteretic first-order transitions. After the two surface layers undergo a first-order transition to the smectic-I phase, the surface hexatic correlation length \(\xi\) evolves smoothly from \(\sim 100 to \sim 300 \mathring{A}\) with a roughly square-root form, \(\xi \sim \mid T-T_c \mid ^{1/2}\)., Engineering and Applied Sciences

About one-third of patients undergoing transcatheter aortic valve implantation (TAVI) use oral anticoagulants (OAC), mainly due to atrial fibrillation. General guidelines advise interrupting OAC in patients with a high risk of bleeding undergoing interventions. However, preliminary observational data suggest that the continuation of OAC during TAVI is safe and may reduce the risk of periprocedural thromboembolic events. The Periprocedural Continuation Versus Interruption of Oral Anticoagulant Drugs During Transcatheter Aortic Valve Implantation (POPular PAUSE TAVI) is a multicentre, randomised clinical trial with open-label treatment and blinded endpoint assessment. Patients are randomised 1:1 to periprocedural continuation versus interruption of OAC and are stratified for vitamin K antagonist or direct oral anticoagulant use. The primary endpoint is a composite of cardiovascular mortality, all stroke, myocardial infarction, major vascular complications and type 2-4 bleeding within 30 days after TAVI, according to the Valve Academic Research Consortium-3 criteria. Secondary endpoints include separate individual and composite outcomes, quality of life and cost-effectiveness. Since continuation of OAC is associated with the ancillary benefit that it simplifies periprocedural management, the primary outcome is first analysed for non-inferiority; if non-inferiority is proven, superiority will be tested. Recruitment started in November 2020, and the trial will continue until a total of 858 patients have been included and followed for 90 days. In summary, POPular PAUSE TAVI is the first randomised clinical trial to assess the safety and efficacy of periprocedural continuation versus interruption of OAC in patients undergoing TAVI.

Objective: Intranasal administration of dexmedetomidine for monitored anesthesia care (MAC) appears to be an effective, safe, and appropriate alternative to general anesthesia (GA) for ambulatory dental surgery. Based on the available evidence we evaluated a new MAC protocol with intranasal dexmedetomidine as the primary choice. To assess a difference in patient satisfaction and anesthesia-related discomfort between GA and MAC in ambulatory dental surgery, a study was conducted among patients undergoing various dental procedures. Patient satisfaction and anesthesia-related discomfort were assessed on the first postoperative day using the Bauer patient satisfaction questionnaire., Results: Although the differences were small, patients in the MAC group were overall more satisfied with the general care compared to the GA group (p < 0.02). Patients in the MAC group reported more postoperative drowsiness compared to the GA group (p < 0.05), but less postoperative hoarseness and sore throat (p = 0.005 and p < 0.001, respectively). Moreover, postoperative thirst was more common in the GA group (p = 0.002). In conclusion, the differences in patient satisfaction and anesthesia-related discomfort between GA and MAC in this implementation study were small but appeared to favor MAC with intranasal dexmedetomidine over GA as anesthesia method during dental ambulatory surgery., (© 2022. The Author(s).)

Various vaccines were developed to reduce the spread of the Severe Acute Respiratory Syndrome Cov-2 (SARS-CoV-2) virus. Quickly after the start of vaccination, reports emerged that anti-SARS-CoV-2 vaccines, including ChAdOx1-S, could be associated with an increased risk of thrombosis. We investigated the hemostatic changes after ChAdOx1-S vaccination in 631 health care workers. Blood samples were collected 32 days on average after the second ChAdOx1-S vaccination, to evaluate hemostatic markers such as D-dimer, fibrinogen, α2-macroglobulin, FVIII and thrombin generation. Endothelial function was assessed by measuring Von Willebrand Factor (VWF) and active VWF. IL-6 and IL-10 were measured to study the activation of the immune system. Additionally, SARS-CoV-2 anti-nucleoside and anti-spike protein antibody titers were determined. Prothrombin and fibrinogen levels were significantly reduced after vaccination (-7.5% and -16.9%, p < 0.0001). Significantly more vaccinated subjects were outside the normal range compared to controls for prothrombin (42.1% vs. 26.4%, p = 0.026) and antithrombin (23.9% vs. 3.6%, p = 0.0010). Thrombin generation indicated a more procoagulant profile, characterized by a significantly shortened lag time (-11.3%, p < 0.0001) and time-to-peak (-13.0% and p < 0.0001) and an increased peak height (32.6%, p = 0.0015) in vaccinated subjects compared to unvaccinated controls. Increased VWF (+39.5%, p < 0.0001) and active VWF levels (+24.1 %, p < 0.0001) pointed toward endothelial activation, and IL-10 levels were significantly increased (9.29 pg/mL vs. 2.43 pg/mL, p = 0.032). The persistent increase of IL-10 indicates that the immune system remains active after ChAdOx1-S vaccination. This could trigger a pathophysiological mechanism causing an increased thrombin generation profile and vascular endothelial activation, which could subsequently result in and increased risk of thrombotic events., Competing Interests: BL, RdL-K, MR, DH, and MN are employees of Synapse Research Institute, part of Diagnostica Stago. HC received funding for research from Bayer and Pfizer; compensation fees for consultancy and advisory boards from Daaichi, Pfizer, Leo, Bayer, Galapagos, Anthos, Alexion, and Alveron; shareholder from Coagulation profile; all benefits were transferred to the CARIM institute to support investigator-initiated research. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 de Laat, Stragier, de Laat-Kremers, Ninivaggi, Mesotten, Thiessen, Van Pelt, Roest, Penders, Vanelderen, Huskens, De Jongh, Laenen, Fivez, ten Cate, Heylen, Heylen and Steensels.)