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An organocatalytic asymmetric cycloaddition–elimination cascade reaction of aryl enecarbamates with azonaphthalenes has been developed to access axially chiral heterobiaryls in excellent yields and enantioselectivities.

Published data on the association of vascular endothelial growth factor (VEGF) -1154G>A polymorphism with cancer risk is inconclusive. To derive a more precise estimation of association between VEGF -1154G>A polymorphism and the risk of cancer, we performed a meta-analysis of 7,071 cancer cases and 7,693 controls from 16 published case-control studies. Our meta-analysis didn't reveal an association between VEGF -1154G>A polymorphism and overall cancer risk (GG vs. AA: OR: 1.08, 95% CI: 0.96-1.20; GA vs. AA: OR: 1.04, 95% CI: 0.93-1.17; recessive model: GG+GA vs. AA: OR: 1.06, 95% CI: 0.95-1.18; dominant model: GG vs. GA+AA, OR: 1.11, 95% CI: 1.00-1.24). Nevertheless, for non-Caucasians, GG homozygote may have higher cancer risk compared with either A carriers (OR: 1.58, 95% CI: 1.12-2.23) or AA homozygote (OR: 1.43, 95% CI: 1.17-1.76). No significant heterogeneity was detected except in the dominant model and "prostate cancer" subgroup analysis. More studies with larger samples are warranted to confirm these findings.

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Five new tetranuclear complexes based on an 8-hydroxyquinoline Schiff base derivative and the β-diketone coligand, [Ln(acac)L(μ-OH)]·CHCN·0.5CHCl (Ln = Gd (1), Tb (2), Dy (3), Ho (4) and Er (5); HL = 5-(benzylidene)amino-8-hydroxyquinoline; acac = acetylacetonate) have been synthesized, and structurally and magnetically characterized. Complexes 1-5 have similar tetranuclear structures. Each Ln ion is eight coordinated and its coordination polyhedra can be described as being in a distorted square-antiprismatic geometry. The magnetic studies reveal that 1 features the magnetocaloric effect (MCE) with the magnetic entropy change of -ΔS(T) = 25.08 J kg K at 2 K for ΔH = 7 T, and 3 displays the slow magnetic relaxation behavior of Single Molecule Magnets (SMMs) with the anisotropic barrier of 86.20 K and the pre-exponential factor τ = 2.99 × 10 s.

By introducing different β-diketonate coligands, Gd4 complexes show cryogenic magnetic refrigeration properties, whereas Dy4 clusters exhibit different SMMs behaviors.

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