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The authors fabricated a no-bias pi cell using a dual alignment layer with an intermediate pretilt angle via a rubbing. In the dual alignment layer system, the competition between crest region favoring the vertical alignment and trough region favoring planar alignment made it possible to achieve various pretilt angles, and adjusted pretilt angle from 90° to 20° with rubbing. In addition, as the intermediate pretilt angle plays a role in eliminating the activation energy and thus allowing formation of the initial bend state in pi cell fabrication, this approach achieved a no-bias pi cell for a liquid crystal display with both low power consumption and fast response.

Long-term stability of intermediate liquid crystal pretilt angles on a poly(dimethylsiloxane) (PDMS) ultrathin film grafted onto a surface was realized simply and easily via low-energy ion beam (IB) treatment. The composition and surface energy of the thin film could be controlled by varying the low-energy IB treatment. This treatment results in the permanent chemical modification of the film surface, converting it from organic PDMS to a mixed layer of organic PDMS and inorganic silica. The partial transformation of a PDMS surface gives rise to the control of the pretilt angle via the formation of the inhomogeneous surface and the stabilization of the pretilt angle via the cross-linking reaction of broken chemical bonds through IB irradiation. As a result, a continuous variation of pretilt angles that maintained their initial value with long-term stability was obtained. Thus, the unique chemical transformation of the PDMS surface using IB treatment may allow for the production of durable intermediate liquid crystal pretilt angles.

Background Since colon cancer stem cells (CSCs) play an important role in chemoresistance and in tumor recurrence and metastasis, targeting of CSCs has emerged as a sophisticated strategy for cancer therapy. α-mangostin (αM) has been confirmed to have antiproliferative and apoptotic effects on cancer cells. This study aimed to evaluate the selective inhibition of αM on CSCs in colorectal cancer (CRC) and the suppressive effect on 5-fluorouracil (5-FU)-induced CSCs. Methods The cell viability assay was performed to determine the optimal concentration of αM. A sphere forming assay and flow cytometry with CSC markers were carried out to evaluate the αM-mediated inhibition of CSCs. Western blot analysis and quantitative real-time PCR were performed to investigate the effects of αM on the Notch signaling pathway and colon CSCs. The in vivo anticancer efficacy of αM in combination with 5-FU was investigated using a xenograft mouse model. Results αM inhibited the cell viability and reduced the number of spheres in HT29 and SW620 cells. αM treatment decreased CSCs and suppressed the 5-FU-induced an increase in CSCs on flow cytometry. αM markedly suppressed Notch1, NICD1, and Hes1 in the Notch signaling pathway in a time- and dose-dependent manner. Moreover, αM attenuated CSC markers CD44 and CD133, in a manner similar to that upon DAPT treatment, in HT29 cells. In xenograft mice, the tumor and CSC makers were suppressed in the αM group and in the αM group with 5-FU treatment. Conclusion This study shows that low-dose αM inhibits CSCs in CRC and suppresses 5-FU–induced augmentation of CSCs via the Notch signaling pathway.

The intermediate blocking layer (IBL) was investigated for the development of highly efficient and bright organic light-emitting diodes (OLEDs). The insertion of an IBL between a hole transport layer and an emitting layer (EML) has resulted in the development of highly efficient and bright OLEDs. The quantum efficiency and electrical durability at high voltage were highly dependent on the thickness of the IBL. The maximum external quantum efficiency of the devices with a 1.5-nm-thick IBL was increased by 28% compared with the reference. The enhanced performance of the OLEDs appears to be due to the improvement of carrier balance and exciton confinement.