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Adsorptive separation of acetylene (C2H2) from a C2H2/CO2 mixture has emerged as an alternative to replace cryogenic distillation to obtain high purity C2H2 in a safer manner. Al-based metal–organic frameworks, such as MIL-160 and CAU-10–NH2, have been reported as good acetylene adsorbents with high selectivity and high acetylene packing density. According to this, incorporation of hetero atoms in the MOF pore wall clearly has a positive impact on enhancing C2H2 capture performance. Nonetheless, a systematic evaluation of the role played by functional groups within the same MOF structure in their C2H2 sorption performance is still required. In this study, CAU-10 samples were prepared according to the functional group using Al metal ions and various functionalized organic linkers, including pristine terephthalate (–H) and its modified forms (–OH, –F, –NO2, –NH2, and –CH3) to investigate their C2H2 and CO2 adsorption properties. The C2H2/CO2 separation performance of the adsorbents was investigated using single gas adsorption isotherms and by application of the ideal adsorbed solution theory as well as dynamic breakthrough experiments for the gas mixture under dry and humid conditions. Interestingly, CAU-10–CH3 was demonstrated to exhibit a record high packing density of 543 g L−1 at 25 °C for acetylene, 2.8 times higher than the CO2 uptake at 1 bar. A breakthrough mixture experiment using CAU-10–CH3, and CAU-10–NH2 as comparative samples confirmed CAU-10–CH3 as a prominent candidate for acetylene selective adsorption under both dry and humid conditions. The microscopic origin of these attractive adsorption/separation performances was understood from density functional theory calculations and single component/binary mixture grand canonical Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

Background and Objectives: The interspace between the popliteal artery and the posterior capsule of the knee (iPACK) block has been widely used in perioperative settings to control posterior knee pain and can additionally be used for chronic knee pain. In this cadaveric study, we aimed to investigate the needle tip position and its proximity to the articular branch of the tibial nerve (ABTN) during an iPACK-targeted radiofrequency procedure. Materials and Methods: An ultrasound-guided iPACK block was performed on 20 knees of 10 cadavers. We injected 0.1 mL each of blue and green gelatinous dye near the tibial artery (point A) and posterior knee capsule (point B), respectively, and evaluated the spread of both around the ABTN. For a hypothetical conventional radiofrequency ablation (RFA) lesion (diameter, 2.95 mm) and cooled RFA lesion (diameter, 4.9 mm), we counted the number of specimens in which the ABTNs would be captured. Results: The percentage of specimens in which the ABTN would be captured by a cooled RFA lesion was 64.71% at point A and 43.75% at point B (p = 0.334). Meanwhile, the percentage of specimens in which the ABTN would be captured by a conventional RFA lesion was 58.82% from point A and 25% from point B (p = 0.065). Conclusions: When performing an RFA-based iPACK block, the needle tip may be positioned either lateral to the tibial artery or in the space between the posterior knee capsule and the tibial artery. However, more studies with larger samples are needed to verify these results before the clinical use of this procedure can be recommended. [ABSTRACT FROM AUTHOR]

Anatomy instructional methods varied widely during the COVID‐19 pandemic and programs are assessing innovations for retention. Learning preferences were assessed among medical students dichotomized as elective dissectors (ED) or non‐dissectors (ND) during the COVID‐19 partial re‐opening in 2020 (preclinical) and again in 2022 after clinical exposure (post‐clinical) to assess the viability of elective dissection post‐pandemic. A mixed‐method approach was used for the assessment of test scores, learning preference surveys, learning activities rankings, and thematic analyses. No significant differences occurred in anatomy examination scores. Dissection was considered useful by both preclinical groups but significantly more so by ED, while the presence of an instructor was significantly preferred by ED although a majority of ND agreed. Elective dissection was significantly preferred by ND but also by a large minority of ED students. Pre‐ and post‐clinical ND believed that elective dissection offered more academic flexibility, did not hinder clinical learning, and did not negatively impact medical education. The corresponding ED stated that confidence improved, clinical experiences were enhanced, and dissection was irreplaceable. Preclinical ND preferred self‐learning, while ED students preferred online learning, but these differences largely disappeared post‐clinically. Learning activity rankings were not significantly different among all groups (ND, ED, preclinical, and post‐clinical). A hybrid laboratory with a virtual learning environment ranked highest across groups and preferences increased over time suggesting that students benefited from this instructional method during clinical exposure. The absence of laboratory experience ranked lowest, and preference decreased over time suggesting that anatomy dissection is valued. [ABSTRACT FROM AUTHOR]