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Background: Square knots can be difficult to construct in deep body cavities. The reversing half-hitch alternating post (RHAP) surgical knot has noninferior tensile strength and performance characteristics in deep body cavities. We compared the enterotomy repairs of novice learners in simulated deep body cavities using RHAP versus square knots after proficiency-based training. Methods: Undergraduate students were randomized to RHAP (n = 10) or square knot (n = 10) groups and trained to defined proficiency. They then performed hand-sewn enterotomy repairs of cadaveric porcine small bowels on flat surfaces and in simulated deep body cavities. We recorded time to knot-tying proficiency and to enterotomy repair, and burst pressures for the repair. Results: Mean time-to-proficiency in knot tying was equivalent between the RHAP and square knot groups (23 [standard deviation (SD) 3] v. 21 [SD 2] min, p = 0.33). Mean time for enterotomy repair in deep cavities was shorter for the RHAP group (16 [SD 2] min v. 21 [SD 1] min, p = 0.02). Mean burst pressures for enterotomy repair were equivalent on flat surfaces (128 [SD 41] v. 101 [SD 36] mm Hg, p = 0.31), and were significantly higher for the RHAP group in simulated deep body cavities (32 [SD 13] v. 105 [SD 37]mm Hg, p = 0.05). Conclusion: The RHAP knots appear to have superior performance versus square knots when tied in a deep body cavity by novice learners. Future work should focus on demonstrating the clinical relevance and broad utility of the RHAP knot in abdominal surgery. Both knot types should be taught to novice learners. Contexte : L'exécution de noeuds plats peut être difficile dans les cavités corporelles profondes. Les noeuds de type demi-clé inversée alternée (RHAP, pour reversing halfhitch alternating post) ont une résistance à la traction et un rendement semblables à ceux des noeuds plats dans ces cavités. Nous avons comparé l'efficacité des noeuds plats et des noeuds de type RHAP réalisés par de nouveaux apprenants dans des cavités profondes simulées, après leur avoir enseigné les compétences nécessaires. Méthodes : Les étudiants de premier cycle ont été aléatoirement répartis en 2 groupes, soit le groupe RHAP (n = 10) et le groupe noeud plat (n = 10), et ont reçu une formation pour développer des compétences prédéfinies. Ils ont ensuite suturé à la main un intestin grêle provenant d'un cadavre de porc, sur une surface plane et à l'intérieur d'une cavité profonde simulée. Nous avons mesuré le temps nécessaire à l'exécution du noeud et à la suture complète de l'incision, de même que la pression que pouvait subir cette suture sans se rompre. Résultats : Le temps moyen d'exécution du noeud était semblable entre les groupes RHAP et noeud plat (23 min [écart type (E.T.) 3 min] c. 21 min [E.T. 2 min]; p = 0,33). Le temps moyen nécessaire à la suture de l'incision dans la cavité profonde était plus court dans le groupe RHAP (16 min [E.T. 2 min] c. 21 min [E.T. 1 min]; p = 0,02). La pression moyenne que pouvait subir la suture sans se rompre était comparable pour les sutures effectuées sur une surface plane (128 mm Hg [E.T. 41 mm Hg] c. 101 mm Hg [E.T. 36 mm Hg]; p = 0,31), mais était significativement plus élevée dans le groupe RHAP pour les sutures faites dans la cavité profonde (32 mm Hg [E.T. 13 mm Hg] c. 105 mm Hg [E.T. 37 mm Hg], p = 0,05). Conclusion : Les noeuds de type RHAP semblent avoir un rendement supérieur à celui des noeuds plats lorsqu'ils sont réalisés dans une cavité profonde par de nouveaux apprenants. Des études ultérieures devraient se pencher sur la pertinence clinique et l'utilité générale de ces noeuds en chirurgie abdominale. Les 2 types de noeuds devraient être enseignés aux nouveaux apprenants., Suturing and hand-tying surgical knots are essential skills for a variety of medical specialties. Various surgical knot configurations with different tensile strengths and mechanisms of failure have been developed for [...]

We developed a high‐resolution and noninvasive multichannel urodynamic system combined with a novel signal‐processing algorithm tailored to extract electromyographic (EMG) activity from the urinary bladder. We utilized a flexible noninvasive biopotential recording system to collect an array of EMG signals from the urinary bladder of human subjects. This study also presents the use of an existing artifact rejection methodology to autonomously extract an EMG signal from an environment prone to motion artifacts. [ABSTRACT FROM AUTHOR]

Background: Square knots are the gold standard in hand-tie wound closure, but are difficult to reproduce in deep cavities, inadvertently resulting in slipknots. The reversing half-hitch alternating post (RHAP) knot [...]

Key points: CRSwNP patients had decreased nNO and increased SNOT‐22, endoscopy, and CT scores.CRSwNP patients exhibited decreased nNO despite elevated iNOS and eNOS mRNA expression.The mechanism behind lowered nNO in CRSwNP may not be related to NOS expression. [ABSTRACT FROM AUTHOR]

Mn‐redox‐based oxides and oxyfluorides are considered the most promising earth‐abundant high‐energy cathode materials for next‐generation lithium‐ion batteries. While high capacities are obtained in high‐Mn content cathodes such as Li‐ and Mn‐rich layered and spinel‐type materials, local structure changes and structural distortions (often lead to voltage fade, capacity decay, and impedance rise, resulting in unacceptable electrochemical performance upon cycling. In the present study, structural transformations that exploit the high capacity of Mn‐rich oxyfluorides while enabling stable cycling, in stark contrast to commonly observed structural changes that result in rapid performance degradation, are reported. It is shown that upon cycling of a cation‐disordered rocksalt (DRX) cathode (Li1.1Mn0.8Ti0.1O1.9F0.1, an ultrahigh capacity of ≈320 mAh g−1 (energy density of ≈900 Wh kg−1) can be obtained through dynamic structural rearrangements upon cycling , along with a unique voltage profile evolution and capacity rise. At high voltage, the presence of Mn4+ and Li+ vacancies promotes local cation ordering, leading to the formation of domains of a "δ phase" within the disordered framework. On deep discharge, Mn4+ reduction, along with Li+ insertion transform the structure to a partially ordered DRX phase with a β′‐LiFeO2‐type arrangement. At the nanoscale, domains of the in situ formed phases are randomly oriented, allowing highly reversible structural changes and stable electrochemical cycling. These new insights not only help explain the superior electrochemical performance of high‐Mn DRXbut also provide guidance for the future development of Mn‐based, high‐energy density oxide, and oxyfluoride cathode materials. [ABSTRACT FROM AUTHOR]