Rope-like bundles of single-walled carbon nanotubes (SWNTs) similar to those obtained by laser vaporization and electric-arc techniques were synthesized on a relatively large scale and at low cost by the catalytic decomposition of hydrocarbons at a temperature of about 1200 °C using an improved floating catalyst method. The SWNTs thus obtained have larger diameters and are self-organized into ropes. The addition of thiophene was found to be effective in promoting the growth of SWNTs and in increasing the yield of either SWNTs or multiwalled carbon nanotubes under different growth conditions.

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Fine structures appearing on the phase transition from h (hexagonal) to c (cubic) boron nitride under high pressure (7.7 GPa) and high temperature (1800–2150 °C) are examined by high-resolution transmission electron microscopy. A prominent contraction of the interplanar spacing between sp2 sheets from 3.33 to 3.10 Å in so-called ‘‘compressed h-BN’’ is attributable to a monoclinic lattice distortion of the residual h-BN, which originates from the difference in the compressibility as well as the thermal expansion between adjoining h- and c-BN grains. The parameters of the monoclinic unit cell are am=4.33, bm=2.50, cm=3.1–3.3 Å, and β=92–95°. Thin plates of h-BN are often folded and the folding also causes the monoclinic structure. The sheet sequence of r (rhombohedral)-BN locally appears when the strong volume shrinkage occurs due to the formation of a c-BN grain. Nanoscale twins appear in resulting c-BN grains, as long as they are small, and w (wurzite)-BN is sometimes included in them.

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Somatic mutations in the EGFR tyrosine kinase domain play a critical role in the development and treatment of non-small cell lung cancer (NSCLC). Strong genetic influence on susceptibility to these mutations has been suggested. To identify the genetic factors conferring risk for the EGFR tyrosine kinase mutations in NSCLC, a case-control study was conducted in 141 Taiwanese NSCLC patients by focusing on three functional polymorphisms in the EGFR gene [À216G/T, intron 1 (CA)n, and R497K]. Allelic imbalance of the EGFR À216G/T polymorphism was also tested in the heterozygous patients and in the NCI-60 cancer cell lines to further verify its function. We found that the frequencies of the alleles À216T and CA-19 are significantly higher in the patients with any mutation (P ¼ 0.032 and 0.01, respectively), in particular in those with exon 19 microdeletions (P ¼ 0.006 and 0.033, respectively), but not in the patients with L858R mutation. The À216T allele is favored to be amplified in both tumor DNA of lung cancer patients and cancer cell lines. We conclude that the local haplotype structures across the EGFR gene may favor the development of cellular malignancies and thus significantly confer risk to the occurrence of EGFR mutations in NSCLC, particularly the exon 19 microdeletions. Cancer Res; 71(7); 2423-7. Ó2011 AACR.

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