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Perovskite manganite oxides have attracted considerable attention due to their strong electronic correlation. However, their practical application is challenged by high manufacturing costs and inferior electrical properties. In this study, the sol–gel method was employed to precisely control the Sr content in La1−xSrxMnO3 (LSMO, x = 0.175, 0.195, 0.215, and 0.235) polycrystalline ceramics, the relationship between doping levels and electrical transport properties was systematically investigated. The results show that substituting La3+ with Sr2+ can effectively tune the electrical transport properties of LSMO ceramics. X-ray diffraction analysis indicates that all samples exhibit a single-phase perovskite structure with no secondary phases detected. Scanning electron microscopy images reveal that the sample surfaces have good grain connectivity, with grain size increasing as the Sr doping level increases. The resistivity–temperature curves of the samples were measured using the standard four-probe method, and significant differences of electrical transport properties were observed within the range of Sr doping studied. Notably, when the Sr doping level is x = 0.195, the temperature coefficient of resistivity (TCR) value of LSMO ceramics increases significantly to 10.3% K−1 at the peak TCR temperature (Tk) of 296.3 K. In summary, these results offer a theoretical basis and guidance for future development of highly sensitive uncooled infrared bolometers. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) refers to an endocrine disorder syndrome that are correlated with multiple organs and systems. PCOS has an effect on women at all stages of their lives, and it has an incidence nearly ranging from 6% to 20% worldwide. Mitochondrial dysfunctions (e.g., oxidative stress, dynamic imbalance, and abnormal quality control system) have been identified in patients and animal models of PCOS, and the above processes may play a certain role in the development of PCOS and its associated complications. However, their specific pathogenic roles should be investigated in depth. In this review, recent studies on the mechanisms of action of mitochondrial dysfunction in PCOS and its associated clinical manifestations are summarized from the perspective of tissues and organs, and some studies on the treatment of the disease by improving mitochondrial function are reviewed to highlight key role of mitochondrial dysfunction in this syndrome. [ABSTRACT FROM AUTHOR]