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We herein report on the synthesis, structure, and use in alkyne hydroboration catalysis of [(IPrCl)Zn−R]+ and [(ItBu)Zn−R]+ cations bearing IPrCl (IPrCl=1,3‐bis[2,6‐bis(1‐methylethyl)phenyl]‐4,5‐dichloro‐1,3‐dihydro‐imidazol‐2‐ylidene) and the sterically demanding ItBu carbene (ItBu=1,3‐bis(1,1‐dimethylethyl)−1,3‐dihydro‐imidazol‐2‐ylidene). Ionization of neutral precursors [(IPrCl)ZnR2] (1 a, R=Et; 1 b, R=Me) and [(ItBu)ZnEt2] (2) with one equivalent of [Ph3C][B(C6F5)4] led to with robust and stable two‐coordinate ZnII cations [(IPrCl)Zn−R]+ (3 a, R=Et; 3 b, R=Me) and [(ItBu)Zn−Et]+ (4), respectively, all isolated as [B(C6F5)4]− salts. Further derivatization of alkyl cations 3 b and 4 by reaction with one equivalent of [B(C6F5)3] afforded cations [(IPrCl)Zn−C6F5]+ (5) and [(ItBu)Zn−C6F5]+ (6) as [B(C6F5)4]− salts, with cation 6 displaying a limited stability in solution. The molecular structures of cations 3 b, 4 and 5 were confirmed through X‐ray diffraction studies. Among stable cations, Fluoride ion affinity (FIA) estimations agree with cation 5 being the most Lewis acidic in thus far reported [(IPrCl)Zn−R]+ cations. In the presence of pinacol borane and 1‐octyne, cations 3 a–b, 5 and [(IPrCl)Zn−C6F5]+ (5 mol%) slowly catalyze the selective cis‐hydroboration of 1‐octyne to the vinylborane product A. Cation 5 also mediates 2‐hexyne hydroboration to afford a mixture of hydroboration products B and C. In the case of hydroboration catalysis mediated by cations 5 and [(IPrCl)Zn−C6F5]+, experimental data and preliminary DFT calculations are consistent a Lewis‐acid‐type catalysis. [ABSTRACT FROM AUTHOR]

Since the beginning of the 2000's, homogeneous gold catalysis has emerged as a powerful tool to promote the cyclization of unsaturated substrates with excellent regioselectivity allowing the synthesis of elaborated organic scaffolds. An important goal to achieve in gold catalysis is the possibility to induce enantioselective transformations by the assistance of chiral complexes. Unfortunately, the linear geometry of coordination for gold usually encountered in complexes at the +1 oxidation states renders this goal very challenging. In consequence, the interest toward the synthesis of chiral gold(III) complexes is steadily growing. Indeed, the square planar geometry of the gold(III) cation appears more suitable to promote chiral induction. Beside catalysis, gold(III) complexes have also shown promising potential in the field of pharmacology. Herein, syntheses and applications of well‐defined gold(III) complexes reported over the last fifteen years are summarized. [ABSTRACT FROM AUTHOR]

Merging gold(I) cations with polyoxometalate anions results in various interclusters and complexes. Herein, the synthesis of these newly emerging gold(I)/polyoxometalate materials is reviewed. The applications of these promising hybrids in organic catalysis are also summarized and evaluated in terms of the advantages and limitations of the catalysts including efficiency, synergistic effects and recyclability. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The aim of the present study was to assess the validity of clusters combining history elements and physical examination tests to diagnose symptomatic knee osteoarthritis (SOA) compared with other knee disorders. Methods: This was a prospective diagnostic accuracy study, in which 279 consecutive patients consulting for a knee complaint were assessed. History elements and standardized physical examination tests were obtained independently by a physiotherapist and compared with an expert physician's composite diagnosis, including clinical examination and imaging. Recursive partitioning was used to develop diagnostic clusters for SOA. Diagnostic accuracy measures were calculated, including sensitivity, specificity, and positive and negative likelihood ratios (LR+/−), with associated 95% confidence intervals (CIs). Results: A total of 129 patients had a diagnosis of SOA (46.2%). Most cases (76%) had combined tibiofemoral and patellofemoral knee OA and 63% had radiological Kellgren–Lawrence grades of 2 or 3. Different combinations of history elements and physical examination tests were used in clusters accurately to discriminate SOA from other knee disorders. These included age of patients, body mass index, presence of valgus/varus knee misalignment, palpable knee crepitus and limited passive knee extension. Two clusters to rule in SOA reached an LR+ of 13.6 (95% CI 6.5 to 28.4) and three clusters to rule out SOA reached an LR– of 0.11 (95% CI 0.06 to 0.20). Discussion: Diagnostic clusters combining history elements and physical examination tests were able to support the differential diagnosis of SOA compared with various knee disorders without relying systematically on imaging. This could support primary care clinicians' role in the efficient management of these patients. [ABSTRACT FROM AUTHOR]

Abstract: The new hybrid NHC gold(I) acetonitrile polyoxometalate complexes {[Au(IPr)(MeCN)+][H+]3[SiW12O404−] (1), [Au(IPr)(MeCN)+][H+]2[PMo12O403−] (2), [Au(IPr)(MeCN)+][H+]5[P2W18O626−] (3), [Au(IPr)(MeCN)+][H+]2[PW12O403−] (4), [Au(IPr)(MeCN)+]3[PMo12O403−] (5) and [Au(ItBu)(MeCN)+] [H+]2[PMo12O403−] (6)} were readily synthesized in high yield and characterized by NMR and MS‐ESI spectroscopy. In a preliminary catalytic study, their activity was assessed under heterogeneous conditions for the ene‐yne rearrangement reaction and a cycloisomerization reaction. Additionally, their reactivity and recyclability were tested in the hydration of alkynes under homogeneous conditions. [ABSTRACT FROM AUTHOR]

Background: The current approach to the clinical diagnosis of traumatic and degenerative symptomatic meniscal tears (SMTs) proposes combining history elements and physical examination tests without systematic prescription of imaging investigations, yet the evidence to support this diagnostic approach is scarce.Objective: To assess the validity of diagnostic clusters combining history elements and physical examination tests to diagnose or exclude traumatic and degenerative SMT compared with other knee disorders.Design: Prospective diagnostic accuracy study.Settings: Patients were recruited from 2 orthopedic clinics, 2 family medicine clinics, and from a university community.Patients: A total of 279 consecutive patients who underwent consultation for a new knee complaint.Methods: Each patient was assessed independently by 2 evaluators. History elements and standardized physical examination tests performed by a physiotherapist were compared with the reference standard: an expert physicians' composite diagnosis including a clinical examination and confirmatory magnetic resonance imaging. Participating expert physicians were orthopedic surgeons (n = 3) or sport medicine physicians (n = 2). Penalized logistic regression (least absolute shrinkage and selection operator) was used to identify history elements and physical examination tests associated with the diagnosis of SMT and recursive partitioning was used to develop diagnostic clusters.Main Outcome Measures: Diagnostic accuracy measures were calculated including sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios (LR+/-) with associated 95% confidence intervals (CIs).Results: Eighty patients had a diagnosis of SMT (28.7%), including 35 traumatic tears and 45 degenerative tears. The combination a history of trauma during a pivot, medial knee pain location, and a positive medial joint line tenderness test was able to diagnose (LR+ = 8.9; 95% CI 6.1-13.1) or exclude (LR- = 0.10; 95% CI 0.03-0.28) a traumatic SMT. Combining a history of progressive onset of pain, medial knee pain location, pain while pivoting, absence of valgus or varus knee misalignment, or full passive knee flexion was able to moderately diagnose (LR+ = 6.4; 95% CI 4.0-10.4) or exclude (LR- = 0.10; 95% CI 0.03-0.31) a degenerative SMT. Internal validation estimates were slightly lower for all clusters but demonstrated positive LR superior to 5 and negative LR inferior to 0.2 indicating moderate shift in posttest probability.Conclusion: Diagnostic clusters combining history elements and physical examination tests can support the differential diagnosis of SMT. These results represent the initial derivation of the clusters and external validation is mandatory.Level Of Evidence: I. [ABSTRACT FROM AUTHOR]

Water-soluble gold(III/I) N-heterocylic carbene complexes behave as efficient catalysts for the hydration of terminal alkynes in neat water. The transformation proceeds in the absence of Brønsted acids or halide scavengers and is suitable for sensitive substrates. Kinetic profiles and DFT studies provide a clear picture of intermediates present during catalysis. [ABSTRACT FROM AUTHOR]

Objective The purpose of the current study was to assess, in patients scheduled for primary total knee replacement (TKR), the effects of pre-surgery waiting time on pain and functional limitations related to the knee joint undergoing surgery, on health-related quality of life (HRQoL) and on contralateral knee pain 6 months after surgery. Method A total of 141 patients scheduled for TKR were recruited from three hospitals in Quebec City, Canada, and followed up until 6 months after surgery. Pre-surgery wait, defined as the time between enrolment on the pre-surgery waiting list and surgery, was considered in four categories (≤3, >3-6, >6-9, >9 months). Pain and functional limitations were measured with the Western Ontario and McMaster Osteoarthritis Index (WOMAC). HRQoL was measured with the SF-36. Results Mean pre-surgery waiting time was 184 (SD: 120.8) days. Six months after TKR, a significant difference was seen between the four groups of pre-surgery wait in terms of HRQoL SF-36 role physical [ F(3, 136) = 2.74, P = 0.046] and contralateral knee WOMAC pain [ F(3, 136) = 5.78, P = 0.0009] scores. Participants with the longest pre-surgery wait (>9 months) showed the worst scores 6 months after TKR. Conclusions Longer pre-surgery waiting time had a negative clinically important impact on HRQoL and contralateral knee pain 6 months after surgery. [ABSTRACT FROM AUTHOR]

Keywords: catalysis; chiral ligands; enantioselectivity; gold EN catalysis chiral ligands enantioselectivity gold 1 1 1 06/30/21 20210625 NES 210625 B Since two decades b , tremendous progresses were made in gold chemistry. This is particularly true in the field of enantioselective catalysis, where the gold(III) complexes are expected to provide better asymmetric inductions. Despite a more challenging chemistry, gold(III) complexes have recently attracted more and more attention as potential surrogates of gold(I) complexes. [Extracted from the article]

Family medicine programmes at Canadian universities have expanded dramatically over the past several years. The development of effective means of faculty evaluation is a real concern for these departments as they strive to maintain the high quality of their teaching programmes in the face of rapid change. The literature on faculty evaluation, including reviews and articles discussing the application of faculty evaluations, is reviewed. The current state of faculty evaluation at three Canadian family medicine departments has also been surveyed. Student evaluations were found to be valid, accurate and well studied. They are not perfect, however, and require the use of additional methods such as peer review or video review in conjunction in order to provide a comprehensive evaluation of all areas of faculty activity. Faculty evaluation in family medicine teaching units and community-based settings has not been well studied. Our survey of faculty evaluation at three Canadian universities shows much room for improvement, particularly in community-based settings where evaluation is almost non-existent. Expanding the use of faculty evaluations for formative means and linking evaluation to faculty development opportunities are essential if improvements to the currently used systems are to be successful and accepted by faculty. Special consideration must be given to community-based settings where systems designed for use in larger university settings will need to be modified substantially before they can be used effectively. Further research is required in this area. [ABSTRACT FROM AUTHOR]

Highlights from the article: Keywords: catalysis; cluster compounds; gold; phosphane ligands; polyoxometalates Catalysis, cluster compounds, gold, phosphane ligands, polyoxometalates.