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A Lewis-base-catalyzed three-component electrophilic thiofunctionalization of cyclopropene with phenol is developed to furnish various trisubstituted chromanes in high trans-diasteroselectivity. This metal-free protocol is easy to scale-up, offers a unique 2,2,3-substitution pattern, and delivers chromanes with diversified core substitution patterns. The unprecedented tolerance of strong electron-withdrawing substituents at the phenol renders the protocol indispensable to access the otherwise inaccessible chromane chemical space that is important for medicinal chemistry campaigns.We performed a systematized review examining the existing literature on undergraduate healthcare students' perceptions and experiences with debriefing methods in simulation-based education. Twenty empirical research articles published in English between 2008 and 2020 were identified during a systematic search of 4 electronic databases. Data derived from these articles underwent critical appraisal and thematic analysis.Students valued the opportunity in debriefing for reflection, raising self-awareness of skills and learning. They preferred structured debriefing for promoting analytic skills and transfer of learning, favored video-assisted debriefing for fast recall and improving communication skills, and benefited most from instructor-led rather than peer-led debriefing. However, students appreciated group debriefing for aiding the construction of new understandings. There was no consensus on the preferred timing of debriefing, and students highlighted their concern about the disclosure of errors across different debriefing methods. Recommendations for educators to improve debriefing experiences and for future research are considered.Tryptophan hydroxylases catalyze the first and rate-limiting step in the synthesis of serotonin. Serotonin is a key neurotransmitter in the central nervous system and, in the periphery, functions as a local hormone with multiple physiological functions. Studies in genetically altered mouse models have shown that dysregulation of peripheral serotonin levels leads to metabolic, inflammatory, and fibrotic diseases. Overproduction of serotonin by tumor cells causes severe symptoms typical for the carcinoid syndrome, and tryptophan hydroxylase inhibitors are already in clinical use for patients suffering from this disease. [https://www.selleckchem.com/products/thiamet-g.html Thiamet G] Here, we describe a novel class of potent tryptophan hydroxylase inhibitors, characterized by spanning all active binding sites important for catalysis, specifically those of the cosubstrate pterin, the substrate tryptophan as well as directly chelating the catalytic iron ion. The inhibitors were designed to efficiently reduce serotonin in the periphery while not passing the blood-brain barrier, thus preserving serotonin levels in the brain.The para-hydrogen (p-H2) matrix-isolation technique has been scarcely used to record electronic absorption and emission spectra. It is expected that its small matrix shifts due to diminished molecular interactions and the softness of the lattice might be advantageous to help identify the carriers of the diffuse interstellar bands. In this article, we present infrared, fluorescence excitation, and dispersed fluorescence spectra of sumanene (C21H12), a bowl-shaped polycyclic aromatic hydrocarbon and a fragment of C60, isolated in solid p-H2. The recorded vibrational wavenumbers from infrared and dispersed fluorescence agree with the scaled harmonic vibrational wavenumbers calculated with the B3PW91/6-311++G(2d,2p) and B3LYP/6-311++G(2d,2p) methods. The recorded fluorescence excitation spectra are consistent with the spectra of jet-cooled gas-phase C21H12 reported previously by Kunishige et al. We found a rather small matrix shift of 55 cm-1 for the S1-S0 electronic transition origin located at 27 888 cm-1. Vibrational wavenumbers associated with the S1 state of C21H12 inferred from the experimental spectrum can be assigned mostly to fundamental normal modes; they are in satisfactory agreement with scaled harmonic vibrational wavenumbers calculated at the TD-B3PW91/6-311++G(2d,2p) level of theory. Significantly more vibrational modes of the S1 state were identified as compared with those in the reported gas-phase work. The potential of p-H2 matrix-isolation spectroscopy to provide electronic excitation spectra suitable for comparison to astronomical observations is discussed by comparing the spectra of C21H12 isolated in solid p-H2 and in solid Ne, a matrix host commonly employed in astrochemistry.<br /><br /> Situation awareness (SA) training is a vital part of healthcare training, and opportunities to provide SA training to healthcare workers are limited in low- and middle-income countries. We aimed to analyze undergraduate medical and nursing students' perception of their understanding of SA through an interprofessional obstetric neonatal emergency simulation workshop (ONE-Sim) and subsequently evaluate their perceived changes in SA understanding using the Endsley model ( Hum Factors 1995;37(1)32-64).<br /><br /> Feedback on SA before and after the workshop was collected through questionnaire-based surveys. Thematic analysis was performed, with themes emerging from an inductive analysis followed by a deductive analysis using the Endsley model.<br /><br /> The themes emerging from the inductive analysis included environmental awareness, evolving knowledge, skill development, and applicability to practice. These aligned with the 3 levels of SA in the Endsley model in the deductive analysis suggesting that participants transformed their perception, comprehension, and projection of SA after the workshop.<br /><br /> Simulation-based education enhanced SA perception in obstetric and neonatal emergencies for medical and nursing students in a low- and middle-income country, and the Endsley model is a feasible framework to measure learner perceived changes in SA understanding through simulation-based education.<br /><br />Simulation-based education enhanced SA perception in obstetric and neonatal emergencies for medical and nursing students in a low- and middle-income country, and the Endsley model is a feasible framework to measure learner perceived changes in SA understanding through simulation-based education.<br /><br /> An effective simulation program allows both the acquisition of surgical skills on the simulated model and the transfer of these skills to a surgical scenario. We designed a forefoot osteotomy training program and sought to determine the transferability to a cadaveric surgical scenario.<br /><br /> Eleven orthopedic residents and 2 foot and ankle surgeons were included. A foot simulator was used. All residents were instructed on the surgical techniques of Chevron, Akin, and triple Weil osteotomies. Eight junior residents (trainees) were enrolled in a supervised simulation program. Baseline assessment was performed on the simulator with the Objective Structured Assessment of Technical Skills (OSATS) and the Imperial College Surgical Assessment Device (ICSAD). After baseline, trainees completed a training program and had a final evaluation of proficiency on the simulator and on cadaveric specimens. Three senior residents with no simulated training (controls) and experts were assessed for comparison.<br /><br /> All trainees improved from a baseline OSATS score of 11 points (9-20) to a final score of 35 points (33-35) in the simulator and 34 points (32-34) in the cadaveric specimen (P &lt; 0.01). Compared with baseline, the ICSAD results improved in path length (391 [205-544] to 131 [73-278] meters, P &lt; 0.01) and number of movements (2756 [1258-3338] to 992 [478-1908], P &lt; 0.01). The final OSATS and ICSAD scores did not differ from experts (P = 0.1) and were significantly different from untrained residents (P = 0.02).<br /><br /> Simulated training of Chevron, Akin, and triple Weil osteotomies in orthopedic residents improved procedural proficiency, enabling successful skill transfer to a surgical scenario in cadavers.<br /><br /> II (Prospective Cohort Study).<br /><br />II (Prospective Cohort Study).The intensification of aquaculture in Cameroon requires efficient screening methods to control veterinary drug residues in fish. This is why the charm II radio receptor technique for the detection of antimicrobial residues in aquaculture fish initiated in Belgium was transferred to Cameroon according to Commission Decision 2002/657/EC. The validation parameters included the following tests repeatability, reproducibility and robustness in addition to the mandatory characteristics, detection capability and specificity. Selected veterinary drug-free fish samples of tilapia (Oreochromis niloticus), catfish (Clarias gariepinus), carp (Cyprinus Carpio) and kanga (Heterotis niloticus) were spiked at different target concentrations with different antimicrobials (β-lactams, tetracycline, sulfonamides, macrolides and chloramphenicol). The detection capabilities (CCβ) were at MRPL (0.3 µg/kg for chloramphenicol), or below the regulatory limits in a range of 0.25-0.5 MRL with 0% false-negative results. β-lactams (peniciln, robustness and specificity) were suitable and comparable to the initial validation results, indicating that the transfer to Cameroon laboratory was valid, the method was reliable and could be used in aquaculture fish quality monitoring programs in Cameroon.Biaryl phosphines bearing C(Ar)-C(Ar) axial chirality are commonly known and have been successfully applied in many asymmetric catalyses. Nevertheless, the development of a chiral ligand having an axially chiral C(Ar)-N backbone remains elusive due to its undesirable less restricted rotational barrier. In fact, it is highly attractive to overcome this challenge in ligand development as the incorporation of an N-donor component at the chiral axis is more favorable toward the transient metal coordination, and thus, a better outcome of stereocommunication is anticipated to the approaching substrates. Herein, we present a rational design of a new collection of chiral phosphines featuring a C-N axial chirality and their applications in enantioselective Suzuki-Miyaura cross-coupling for accessing highly steric hindered tetra-ortho-substituted biaryls (26 examples up to 982 er). It is worth noting that the embodied carbazolyl framework is crucial to succeed the reaction, by the fruitful steric relief of bulky substrate coordination and transmetalation via a fleeting Pd-N jumping to Pd-π fashion. DFT calculation reveals an interesting Pd-arene-walking characteristic across the carbazolyl plane for attaining a lower energy-preferred route in a catalytic cycle. The theoretical study successfully predicts the stereooutcome and matches the enantioselectivity with the experimental results.Shortly after the implementation of community mitigation measures in response to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), sharp declines in respiratory syncytial virus and influenza circulation were noted; post-mitigation circulation of other respiratory pathogens has gone unexplored. We retrospectively analyzed all records of a provider-ordered multiplex test between April 1, 2018, and July 31, 2021, in Nashville, Tennessee, and we noted disrupted historical seasonal patterns for common respiratory pathogens during the SARS-CoV-2 pandemic.