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Objectives: The aim of this study was to examine the independent and joint associations of baseline coronary artery calcium score (CACS) and cystatin C (Cys‐C) with the risk of major adverse cardiac and cerebrovascular events (MACCEs) and all‐cause death in symptomatic populations. Methods: The study included 7140 patients with symptom of chest pain who underwent cardiac computerized tomography examinations to measure CACS. All of them had serum Cys‐C results. Endpoints were set for MACCEs and all‐cause death events. Results: A total of 7140 participants were followed for a median of 1106 days. A total of 305 patients had experienced MACCEs and 191 patients had experienced all‐cause death. CACS ≥ 100 and Cys‐C ≥ 0.995 mg/L were independently associated with an increased risk of MACCEs (adjusted hazard ratio [HR]: 1.46; 95% confidence interval [CI]: 1.15–1.85; p =.002 and adjusted HR: 1.57; 95% CI: 1.24–2.00; p <.001, respectively). Compared with CACS < 100 and Cys‐C < 0.995 mg/L patients, CACS ≥ 100 and Cys‐C ≥ 0.995 mg/L patients had the highest risk of MACCEs and all‐cause death (adjusted HR: 2.33; 95% CI: 1.64–3.29; p <.001 and adjusted HR: 2.85; 95% CI: 1.79–4.55; p <.001, respectively). Even in patients with CACS < 100, Cys‐C ≥ 0.995 mg/L was also associated with a higher risk of MACCEs and all‐cause death than Cys‐C < 0.995 mg/L (adjusted HR: 1.76; p =.003 and adjusted HR: 2.02; p =.007, respectively). Conclusions: The combined stratification of CACS and Cys‐C showed an incremental risk of MACCEs and all‐cause death, reflecting complementary prognostic value. Our results support the combination of the two indicators for risk stratification and event prediction. [ABSTRACT FROM AUTHOR]

Introducing 2,3-dimethyl-1H-imidazol-3-ium iodide (Dmim) as a monodentate ligand during the preparation of ZIF-8 yields ZIF-8 + (50) and ZIF-8 + (38) with cationic 'missing linker' defects. ZIF-8 + (38) adsorbs 125I2 and the resulting radioactive host–guest complex exhibits in vitro cytotoxicity comparable to that of Na125I against colon cancer cell line CT26. [ABSTRACT FROM AUTHOR]

Transition-metal-doped boron clusters have received considerable attention in recent years. The experimentally observed planar or quasi-planar C2h B10(I), C2v B11−(II), C3v B12(III), and C2v B13+ (IV) are known to be boron analogs of benzene. Extensive global minimum searches and first-principles theory investigations performed herein indicate that doping these aromatic boron clusters with a nickel atom generates the closed-shell half-sandwich complexes C2v NiB10(1,1A1), Cs NiB11−(2, 1A′), C3v NiB12(3, 1A1), and Cs NiB13+ (4, 1A′) which are all well-defined global minima of the systems with the coordination numbers of CN = 10, 11, 12, and 13, respectively. Detailed bonding analyses indicate that these Ni-doped boron complexes are effectively stabilized by coordination interactions between the Ni center and aromatic Bn−/0/+ ligands (n = 10-13) and follow the universal coordination bonding pattern of σ plus π double delocalization. Molecular dynamics simulations show that, among these complex clusters, NiB11−(2) behaves like a Wankel motor at room temperature with the B3 inner wheel rotating almost freely inside the quasi-rotating B8 outer bearing in a concerted mechanism, revealing typical bonding fluctuations/fluxionalities in a molecular motor due to thermal vibrations. The IR, Raman and electronic spectra of the concerned species are computationally simulated to facilitate their experimental characterizations. [ABSTRACT FROM AUTHOR]

Shortly after the discovery of all-boron fullerenes D2d B40−/0 (borospherenes), the first axially chiral borospherenes C3/C2 B39− were characterized in experiments in 2015. Based on extensive global minimum searches and first-principles theory calculations, we present herein two new axially chiral members to the borospherene family: the aromatic cage-like C2 B34(1) and C2 B35+(2). Both B34(1) and B35+(2) feature one B21 boron triple chain on the waist and two equivalent heptagons and hexagons on the cage surface, with the latter being obtained by the addition of B+ into the former at the tetracoordinate defect site. Detailed bonding analyses show that they follow the universal bonding pattern of σ + π double delocalization, with 11 delocalized π bonds over a σ skeleton. Extensive molecular dynamics simulations show that these borospherenes are kinetically stable below 1000 K and start to fluctuate at 1200 K and 1100 K, respectively. The IR, Raman, and UV-vis spectra of 1 and 2 are computationally simulated to facilitate their experimental characterization. [ABSTRACT FROM AUTHOR]

Inspired by the recent discovery of the metal-centered tubular molecular rotor Cs B2-Ta@B18− with the record coordination number of CN = 20 and based on extensive first-principles theory calculations, we present herein the possibility of the largest tubular molecular rotors Cs B3-Ta@B18 (1) and C3v B4-Ta@B18+ (2) and smallest axially chiral endohedral metalloborospherenes D2 Ta@B22− (3 and 3′), unveiling a tubular-to-cage-like structural transition in metal-centered boron clusters at Ta@B22−via effective spherical coordination interactions. The highly stable Ta@B22− (3) as an elegant superatom, which features two equivalent corner-sharing B10 boron double chains interconnected by two B2 units with four equivalent B7 heptagons evenly distributed on the cage surface, conforms to the 18-electron configuration with a bonding pattern of σ + π double delocalization and follows the 2(n + 1)2 electron counting rule for spherical aromaticity (n = 2). Its calculated adiabatic detachment energy of ADE = 3.88 eV represents the electron affinity of the cage-like neutral D2 Ta@B22 which can be viewed as a superhalogen. The infrared, Raman, VCD, and UV-vis spectra of the concerned species are computationally simulated to facilitate their spectral characterizations. [ABSTRACT FROM AUTHOR]

Based on extensive global searches and first-principles theory calculations, we present herein the possibility of double-ring tubular (B2O2)n clusters (n = 6–42) (2–10) rolled up from the most stable one-dimensional (1D) BO double-chain ribbon (1) in boron monoxides. Tubular (3D) (B2O2)n clusters (n≥ 6) are found to be systematically much more stable than their previously proposed planar (2D) counterparts, with a 2D–3D structural transition at B12O12 (2). Detailed bonding analyses on 3D (B2O2)n clusters (2–10) and their precursor 1D BO double-chain ribbon (1) reveal two delocalized B–O–B 3c-2e π bonds over each edge-sharing B4O2 hexagonal unit which form a unique 6c-4e o-bond to help stabilize the systems. The IR, Raman, UV-vis, and photoelectron spectra of the concerned species are computationally simulated to facilitate their experimental characterization. [ABSTRACT FROM AUTHOR]