Modifying phonon thermal conductivity in nanomaterials is important not only for fundamental research but also for practical applications. However, the experiments on tailoring thermal conductivity in nanoscale, especially in two-dimensional materials, are rare due to technical challenges. In this work, we demonstrate the in situ thermal conduction measurement of MoS and find that its thermal conductivity can be continuously tuned to a required value from crystalline to amorphous limits. The reduction of thermal conductivity is understood from phonon-defect scattering that decreases the phonon transmission coefficient. Beyond a threshold, a sharp drop in thermal conductivity is observed, which is believed to be due to a crystalline-amorphous transition. Our method and results provide guidance for potential applications in thermoelectrics, photoelectronics, and energy harvesting where thermal management is critical with further integration and miniaturization.

BackgroundLong noncoding RNAs (lncRNAs) have been acknowledged as important regulators in human cancers, including ovarian cancer. Several reports identified lncRNA FEZF1-AS1 as an oncogene in gastric cancer, colorectal carcinoma, and non-small cell lung cancer (NSCLC). However, the function of FEZF1-AS1 in ovarian cancer remains largely unknown. This study was aimed to investigate the role of FEZF1-AS1 in ovarian cancer.Material/MethodsFEZF1-AS1 expression levels in pairs of ovarian cancer tissues and adjacent normal tissues were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Kaplan-Meier curve analysis was used to determine the correlation between FEZF1-AS1 expression and prognosis in ovarian cancer patients. The effects of FEZF1-AS1 knockdown on ovarian cancer cell proliferation, cell-cycle, and apoptosis were analyzed by Cell Counting Kit-8 (CCK8) and Fluorescence activated Cell Sorting (FACS) assays. Western blot was utilized to assess the effect of FEZF1-AS1 on the activation of JAK-STAT3 pathway.ResultsFEZF1-AS1 was overexpressed in ovarian cancer tissues compared to adjacent normal tissues. Consistently, FEZF1-AS1 expression was also upregulated in ovarian cancer cell lines compared with normal cell line. Furthermore, higher expression of FEZF1-AS1 in ovarian cancer patients contributed to poorer prognosis. FEZF1-AS1 knockdown significantly suppressed the proliferation and promoted apoptosis in ovarian cancer cells. In mechanism, FEZF1-AS1 regulated activation of JAK-STAT3 signaling pathway by modulating STAT3 phosphorylation. Knockdown of FEZF1-AS1 significantly impaired the phosphorylation of STAT3.ConclusionsOur study demonstrated that FEZF1-AS1 exerted an oncogenic role in ovarian cancer via modulating JAK-STAT3 pathway.

The response of carbon-nanotube (CNT) transistors to large tensile strains has not been studied because of lack of stretchable devices. In this letter, we fabricate extremely stretchable single-wall CNT (SWCNT) conductive coatings on flexible and transparent elastomer substrates. We then measure the mechanical and electrical properties of the coatings and found excellent stretchability (Poisson ratio ≈ 0.31). The sheet resistances of the coatings remain largely unchanged under a large tensile strain. We then construct an active transistor on SWCNT thin films, which serve as active channel and electrodes, with polydimethylsiloxane thin film as the gate dielectric layer. The transistor exhibits excellent mechanical stability, showing no noticeable change (less than 5%) in electrical performance up to a large strain of 22.5%. The stretchable SWCNT thin-film transistor exhibits a current on–off ratio of ∼50 and field-effect mobility of ∼24 cm2 V−1 s−1, with 75% transmissivity in visible wavelength. We also found that on–off ratio increases with increased stretch strain, while mobility initially increases and then decreases with increased stretch strain.

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