Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries1,2. However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health4,5. However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol—which is a marker of cardiovascular risk—changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million–4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.</p

Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries1,2. However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health4,5. However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol�which is a marker of cardiovascular risk�changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95 credible interval 3.7 million�4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world. © 2020, The Author(s), under exclusive licence to Springer Nature Limited

Superconductivity in the complex metallic alloy phase ß-Al3Mg2

Transport and thermodynamic properties were studied for the complex metallic compound beta-Al3Mg2, composed of 925 atoms per unit cell. beta-Al3Mg2 exhibits bulk superconductivity below T-c=0.87 K. An exponential temperature dependence of the specific heat well below T-c indicates BCS-like behavior with a nodeless gap of width Delta(BCS)(0)approximate to 1.5 K. The coherence length is derived as xi(0)=4.85x10(-8) m and the Ginzburg Landau parameter kappa(GL)approximate to 13, characterizing beta-Al3Mg2 as a type II superconductor. Superconductivity in beta-Al3Mg2 occurs in the absence of inversion symmetry of the crystal. Surprisingly, in spite of the rather complex crystal structure of beta-Al3Mg2, physical properties turn out to be quite simple

Superconductivity in the complex metallic alloy beta-Al3Mg2

Based on low temperature electrical resistivity and specific heat measurements, we have shown that beta-Al3Mg2 undergoes a phase transition into a superconducting ground state at Tc=0.87 K. Microscopically, superconductivity can be understood in terms of the phonon-mediated BCS model. An exponential behavior of the specific heat well below Tc implies a nodeless superconducting gap in the electronic density of states, of the order of 1.6 K. The initial slope of the upper critical field is deduced to be about −0.2 T/K, while an extrapolation T→0 yields mu0Hc2 about 0.14 T. The limiting pair breaking mechanism seems to be orbital pair breaking, as concluded from the model of Werthamer et al. Superconductivity in beta-Al3Mg2 occurs in a crystal environment without inversion symmetry. Broken inversion symmetry has a distinct influence on the superconducting phase, which usually relies on the formation of pairs of electrons in degenerate states with opposite momentum. The availability of such states is normally guaranteed by time reversal and inversion symmetries. The absence of inversion symmetry would favor a strong antisymmetric spin-orbit coupling and, as a consequence, a mixture of spin-singlet and spintriplet pairs in the superconducting condensate can be expected. The small values of the upper critical field, however, seem to exclude a substantial portion of spin-triplet pairs in the condensate. Moreover, the lightweight elements Al and Mg may be responsible for only a minimal spin-orbit coupling in beta-Al3Mg2; hence, the spin-singlet condensate dominates. Additionally, the very complex crystal structure is supposed to smooth the effect of the missing inversion symmetry. A rather conventional superconductivity seems to appear, which also follows from the agreement of the upper critical field with Werthamer’s model. Presently, only a small number of superconductors without inversion symmetry have been found. Although the crystal structure of beta-Al3Mg2 appears to be rather complicated, the various physical quantities derived in both the superconducting and the normal state region turn out to be simple. In the first approximation, some of these quantities even look like a balanced superposition of pure Al and Mg. The latter follows from macroscopic measurements such as the specific heat and microscopic data like those derived from NMR as well

[Ni(cod)2][Al(ORF)4], a source for naked nickel(I) chemistry

The straightforward synthesis of the cationic, purely organometallic NiI salt [Ni(cod)2]+[Al(ORF)4]− was realized through a reaction between [Ni(cod)2] and Ag[Al(ORF)4] (cod=1,5‐cyclooctadiene). Crystal‐structure analysis and EPR, XANES, and cyclic voltammetry studies confirmed the presence of a homoleptic NiI olefin complex. Weak interactions between the metal center, the ligands, and the anion provide a good starting material for further cationic NiI complexes

Electronic correlations and crystal-field effects in RCu3Ru4 O12 (R=La, Pr, Nd) ELECTRONIC CORRELATIONS and CRYSTAL-FIELD ... A. GÜNTHER et al.

© 2020 American Physical Society. Among the large class of A-site ordered perovskites of stoichiometry AC3B4O12, the rare-earth (R) ruthenates RCu3Ru4O12 (R=La, Pr, Nd) are interesting compounds due both to Ru-4d-derived electronic correlations and to unconventional crystal-electric-field effects of the R ions. Here we report on detailed investigations of these compounds utilizing x-ray diffraction, neutron scattering, magnetic susceptibility, and electrical resistivity measurements as well as heat capacity and nuclear resonance experiments. A broad range of external parameters is scanned and depending on the specific technique, temperatures range from 100 mK to 730 K in external magnetic fields up to 14 T. In this work LaCu3Ru4O12 serves as reference compound with a nonmagnetic A site, characterized in detail recently [S. Riegg, Phys. Rev. B 93, 115149 (2016)2469-995010.1103/PhysRevB.93.115149]. All compounds investigated reveal heavy-fermion behavior with a T2 dependence of the low-temperature electrical resistivity and significantly enhanced Sommerfeld coefficients. Toward low temperatures, the compounds with R=Pr and Nd are dominated by the magnetic moments of the R ions, which occupy crystallographic positions with point-group symmetry Th. The crystal-electric-field effects are clearly visible especially in heat capacity and inelastic neutron scattering data from which the crystal-electric-field parameters are derived. The ground state of the Pr3+ ion is identified as a triplet (G4(1)), whereas for Nd3+ it is a quartet (G67). Evidence for lowering of the Th symmetry is observed at the Pr site at temperatures below 10 K, suggesting the formation of orbital order. Moreover, the spin-lattice relaxation derived from Cu63 nuclear quadrupole resonance indicates characteristic temperatures close to 7 K and 350 mK, probably related to orbital and magnetic order, respectively