Search

Different stoichiometries compounds formed by filled-shell (FS) insulators (e.g., xenon) have been extensively predicted and successfully synthesized under extreme conditions. However, theoretical prediction on solid solution formed by FS materials is lacking. Here, by combining structure searching and ab initiohybrid Metropolis-Monte Carlo/molecular dynamics simulations, we predict that the noble gas xenon and CsI can form thermodynamically stable substitutional solid solutions with hexagonal close-packed at high temperature and high pressure, in which Xe, Cs and I exhibit similar electronegativity and strong metallic feature that are analogous to the solid solution alloys. The existence of short-range order among constituent compositions improves the stability of solid solution. These results shed a new insight on the chemical reactivity between noble gases and alkali-halide compounds and provide valuable reference to understand the formation of multicomponent solid solutions under extreme conditions.

Finding the efficient and accurate schemes to calculate the melting temperature is important for molecular dynamics simulation. We propose a modified void method based on heterogeneous nucleation to validly calculate the melting temperature from solid-liquid coexistence state. It decreases the degree of superheating in the conventional voids method. The efficiency and accuracy of five methods (i.e., hysteresis method, two phase coexistence method, the interface pinning method, the Frenkel-Ladd path method and the modified void method) have been discussed in detail. The calculated results of hysteresis method strongly depend on heating/cooling rate. For the nonequilibrium thermodynamic integration method, the calculated accuracy is consistent with the interface pinning method for monoatomic Cu. For the modified void method the calculated results agree with the nonequilibrium thermodynamic integration method.

To investigate whether patients, who are at risk of major acute coronary events, are safe to undergo and benefit from early intervention after using simvastatin.The study was a randomized, open, two-dosage-controlled trial to evaluate the safety and benefits of simvastatin administered to 197 patients (10 mg group, n = 98 and 20 mg group, n = 99), within 48 hours of hospitalization for a diagnosis of unstable angina or acute myocardial infarction (MI), with total cholesterol (TC)/= 180 mg/dL or low-density lipoprotein cholesterol (LDL-C)/= 100 mg/dL. Lipid levels were measured immediately, followed by the 3rd, 6th and 12th month after admission and all adverse events were recorded during follow-up.TC levels fell by 10.15% and 14.52% in the 10 mg and 20 mg groups (P0.05), and LDL-C levels fell 13.87% and 19.38% in the 10 mg and 20 mg groups, respectively (P0.01), 12 months after using simvastatin. The rates of achieving target TC reached 26.3% and 36.5% in the 10 mg and 20 mg groups (P0.01), and that of LDL-C reached 28.2% and 40.3% in the 10 mg and 20 mg groups, respectively (P0.01). There were higher rates of MI and re-hospitalization resulting from angina pectoris and revascularization in the 10 mg group compared with the 20 mg group.The results suggest that early intervention with the HMG-CoA reductase inhibitor, simvastatin, in acute coronary syndromes is possible and safe. It also indicates that the clinical dosage of simvastatin are relatively smaller than that for satisfactory lipid control in patients with acute coronary syndromes.

To investigate the relationship among -75 bp/+83 bp polymorphism in apolipoprotein A1 (apo A1) gene, lipids levels and the occurrence of coronary atherosclerosis disease (CAD).We determined distributions of two MspI polymorphisms of the apo A1 gene at -75 bp and +83 bp, and blood lipids levels among 137 Chinese patients (92 with CAD and 45 in the control group) in relation to circulating lipids and coronary angiography.The demographic information for 137 subjects showed that subjects with CAD tended to have more unfavorable lipoprotein variables. Genotype distributions at both sites were different between the CAD and control groups. Furthermore, the control group had higher M1-/M2- frequencies than the CAD group (M1: P0.005; M2: P0.05) and the "M1-" (A) and "M2-" alleles were associated with increased high-density lipoprotein cholesterol (HDL-C) (M1-: P0.0001; M2-: P0.05) and apo A1 (M1-: P0.0001; M2-: P0.05) levels. "M1-" and "M2-" were significantly negatively correlated with CAD (P0.01 and P0.05, respectively).Our results suggest that changes from G to A at the -75 bp site and from C to T or G to A at the +83 bp site do increase circulating levels of apo A1 and HDL-C. And those individuals with these changes are likely to have a lower risk of developing CAD.