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Abstract: The polycrystalline compound of perovskite manganite La0.27Pr0.4Ca0.33MnO3 was prepared by the standard solid-state reaction method. The magnetic moment vs temperature was measured in the field H=0.2T to obtain T c. The result indicates that the ferromagnetic–paramagnetic (FM–PM) transitions occur near 115K and a peak due to the charge ordering (CO) near 210K appears in the sample. Infrared absorption spectra of the sample were measured by a Fourier transform infrared spectrophotometer with the wave numbers between 400 and 4400cm−1 in the temperature interval from 20 to 300K. The infrared absorption intensity, which related with the effective carrier numbers obtained from the optical conductivity, decreased with increasing temperature. From the integration of the absorption intensity, it can be seen that the effective carrier numbers also decrease with increasing temperature, which can be attributed to the localization of the polarons. The absorption peak of stretching mode, rising from the vibration of Mn–O bond, was also observed clearly in the sample. [Copyright &y& Elsevier]

Background: The nuclear receptor Rev-erbα/β, a key component of the circadian clock, emerges as a drug target for heart diseases, but the function of cardiac Rev-erb has not been studied in vivo. Circadian disruption is implicated in heart diseases, but it is unknown whether cardiac molecular clock dysfunction is associated with the progression of any naturally occurring human heart diseases. Obesity paradox refers to the seemingly protective role of obesity for heart failure, but the mechanism is unclear., Methods: We generated mouse lines with cardiac-specific Rev-erbα/β knockout (KO), characterized cardiac phenotype, conducted multi-omics (RNA-sequencing, chromatin immunoprecipitation sequencing, proteomics, and metabolomics) analyses, and performed dietary and pharmacological rescue experiments to assess the time-of-the-day effects. We compared the temporal pattern of cardiac clock gene expression with the cardiac dilation severity in failing human hearts., Results: KO mice display progressive dilated cardiomyopathy and lethal heart failure. Inducible ablation of Rev-erbα/β in adult hearts causes similar phenotypes. Impaired fatty acid oxidation in the KO myocardium, in particular, in the light cycle, precedes contractile dysfunctions with a reciprocal overreliance on carbohydrate utilization, in particular, in the dark cycle. Increasing dietary lipid or sugar supply in the dark cycle does not affect cardiac dysfunctions in KO mice. However, obesity coupled with systemic insulin resistance paradoxically ameliorates cardiac dysfunctions in KO mice, associated with rescued expression of lipid oxidation genes only in the light cycle in phase with increased fatty acid availability from adipose lipolysis. Inhibition of glycolysis in the light cycle and lipid oxidation in the dark cycle, but not vice versa, ameliorate cardiac dysfunctions in KO mice. Altered temporal patterns of cardiac Rev-erb gene expression correlate with the cardiac dilation severity in human hearts with dilated cardiomyopathy., Conclusions: The study delineates temporal coordination between clock-mediated anticipation and nutrient-induced response in myocardial metabolism at multi-omics levels. The obesity paradox is attributable to increased cardiac lipid supply from adipose lipolysis in the fasting cycle due to systemic insulin resistance and adiposity. Cardiac molecular chronotypes may be involved in human dilated cardiomyopathy. Myocardial bioenergetics downstream of Rev-erb may be a chronotherapy target in treating heart failure and dilated cardiomyopathy.