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High aspect ratio fillers are predicted to increase the dielectric constant of polymer composites more efficiently than spherical fillers according to the rule of mixtures. Using high aspect ratio fillers is a promising route for creating high dielectric constant, low loss materials at a low filler volume fraction, for use as capacitor and electric field grading materials. In this work, two high aspect ratio fillers were mixed into a polymer matrix, and the dielectric properties of composites were studied. Barium titanate fibers were synthesized by electrospinning a sol-gel, followed by a heat treatment to obtain a perovskite crystal structure. The heat treatment conditions were found to be crucial for obtaining tetragonal barium titanate fibers with high dielectric constant. Graphene platelets were prepared by a thermal shock method, which was found to result in a larger dielectric constant. A combination of barium titanate and graphene platelets yielded the highest dielectric constant when used in a polydimethyl siloxane matrix. The increase in dielectric loss over the pure matrix was small when the volume fraction was below the percolation threshold of graphene platelets. Electric flux density-electric field (D-E) measurements showed a linear dielectric constant in barium titanate filled composites and higher loss when graphene was added. The ac breakdown strength was reduced compared to the neat polymer and was affected by filler aspect ratio. The mechanisms that lead to the observed phenomena are discussed.

Object Studies have shown a link between homocysteine (Hcy) and heart diseases, kidney diseases, cerebrovascular diseases, liver diseases, and other pathological conditions. However, the relationship between Hcy and liver fibrosis (LF) is unclear. Here, we studied the link between plasma Hcy concentration and LF. Methods We determined and recorded the plasma Hcy concentration, general biochemical parameters, and liver stiffness measurement (LSM) in 1582 subjects, followed by statistical data analyses. Results During different stages of LF, we found a considerable difference ( p <0.001 unless specified) in body mass index (BMI), sex, age, Hcy, the levels of alanine transaminase (ALT), gamma-glutamyl transpeptidase (GGT; P = 0.012), triglycerides (TG; P = 0.006), low-density lipoprotein cholesterol (LDL-C), fasting blood glucose (FBS), and platelet count (PLT). There was a strong association between the plasma Hcy concentration and the serum biomarkers of LF ( P <0.001) and the values of LSM ( P <0.001). Conclusion The plasma Hcy concentration was substantially different among different stages of LF. The higher the plasma Hcy concentration, the more evident was the degree of LF.

Primary hepatic carcinosarcoma (HCS) is an extremely rare malignant tumor of the liver that contains carcinomatous and sarcomatous components. The diagnosis, treatment, and prognosis of HCS pose great challenges to clinicians. Herein, we present a case of HCS in a 67-year-old man with unique pathological manifestation. Preoperative magnetic resonance imaging showed a malignant lesion in the right liver and a small sub-focus in the left liver. Radical treatment was performed, including excision of the right posterior lobe of the liver, thrombectomy of the right posterior portal vein, and radiofrequency ablation of lesions in the left liver. The specimens were confirmed to be HCS by pathological examinations, which revealed a combination of poorly differentiated hepatocellular carcinoma, moderately differentiated cholangiocellular carcinoma, and spindle cell sarcoma. Transhepatic arterial chemotherapy and embolization was performed after surgery. Unfortunately, pulmonary metastasis occurred 1.5 months later, which meant a poor prognosis. In this report, we discuss the clinicopathological characteristics of this case and factors that affected surgical outcomes, which may add some ideas for the future diagnosis and treatment of HCS patients.