A new class of silicon-containing poly(p-phenylenevinylene)-related copolymers with a uniform π-conjugated segment regulated by organosilicon units was synthesized by the well-known Wittig reaction between the appropriate diphosphonium salts and the dialdehyde monomer such as terephthaldicarboxaldehyde, 2,5-thiophenedicarboxaldehyde, and N-(2-ethylhexyl)-3,6-diformylcarbazole. The resulting polymers were highly soluble in common organic solvents. They could spin cast onto various substrates to give highly transparent homogeneous thin films without heat treatment. Their glass transition temperatures were in the range of 104−119 °C. The UV−visible absorbance of the present polymers shows strong absorption bands at around 347−387 nm, which corresponds to the π−π* transition of the conjugated segments. Their maximum photoluminescence wavelengths for SiPPV analogues appeared around 420−480 nm in the blue emission region, except a silicon-containing poly(p-phenylenevinylene)-related copolymer having a thiophene unit showed a strong PL peak at 520 nm in the green emission region. In the case of the polymers containing a carbazole unit, their PL spectra show both the highest peak in the PL emissive band at 450 nm and an additional strong emissive band in the green region. The single-layer light-emitting diode of a Al/SiPhPPV or SiPhPVK/ITO glass is fabricated. The threshold voltage is in the range 6−12 V from the I−V curve. The electroluminescence (EL) spectrum of the SiPhPPV gives the highest peak in the EL emissive band at 450 nm, when the operating voltage of 9 V was applied. For the polymer containing a carbazole unit, the EL spectrum of the polymer shows the highest peak in the EL emissive band at 450 nm as well as an additional strong emissive band in the yellow region, when the operating voltage of 10 V was applied. Interestingly, the SiPhPVK gives a strong white emitting light, when the operating voltage of higher than 12 V was applied.

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We have recently reported that β-caryophyllene oxide (CPO) can induce apoptosis, suppress tumor growth, and inhibit metastasis through the suppression of signal transducer and activator of transcription 3, PI3K/AKT/mTOR/S6K1 signaling cascades and ROS-mediated MAPKs activation. In the present study, we found that CPO potentiated the apoptosis induced by tumor necrosis factor α (TNFα) and chemotherapeutic agents, suppressed TNFα-induced tumor cell invasion, all of which are known to require NF-κB activation. We found that TNFα stimulated the expression of gene products involved in anti-apoptosis (IAP1, IAP2, Bcl-2, Bcl-xL, and survivin), proliferation (COX-2, cyclin D1, and c-Myc), invasion (MMP 9 and ICAM-1), and angiogenesis (VEGF) and that CPO treatment suppressed their expression. Because these gene products are also regulated by proinflammatory transcription factor NF-κB, we postulated that CPO may mediate its effects by modulating the NF-κB pathway. We found that CPO blocked both inducible and constitutive NF-κB activation in a wide variety of tumor cells. CPO was also found to inhibit the TNFα-induced degradation of IκBα through the inhibition of activation of IκBα kinase and p65 nuclear translocation and phosphorylation. Interestingly, CPO failed to potentiate the apoptotic effect induced by TNFα in p65 (-/-) cells as compared to the wild-type. Thus, overall, our results indicate that the inhibition of NF-κB is one of major mechanisms by which CPO enhances TNFα-induced apoptosis and suppresses invasion.

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This study presents the application of interferometric synthetic aperture radar (InSAR), small baseline subset (SBAS) algorithm and GIS for subsidence analysis in a mining area located at Gangwon-do, Korea. Several mining areas at the Samchuk coalfield had operating coalmines until [2002][2003]. Ground deformation has occurred as a form of subsidence due to the continuous mining activity or the collapse of residual cavities. Twentythree scenes from a JERS-1 satellite acquired from 1992 to 1998 are used to detect the ground movement by means of the differential InSAR process. Distinctive phase variations induced by subsidence were observed in several interferograms. The SBAS algorithm was applied for a detailed analysis. As a result, it was confirmed that deformation was occurring between September 21, 1992 and September 30, 1998 and attained 22 cm at the most significantly subsiding site. The mean and standard deviation of RMS error were 2.0 cm and 0.78 cm, respectively, showing the level of the error due to the used digital elevation model, unwrapping and atmospheric effect. The SBAS-derived cumulative subsidence map was validated with the underground workings and geological maps in order to find the spatial relations and subsiding mechanism. From the spatial comparison with these data, it was shown that the subsidence has taken place above excavations and fault lines.