X‐ray Photoelectron Spectroscopy (XPS) was used to investigate the silicon nitride composition in stacked Si oxide/Si nitride/Si oxide nano‐layers. The standard approach for stoichiometry estimation, valid for homogeneous compositions, was corrected for the case of very small thickness and thin overlayer. Copyright © 2012 John Wiley & Sons, Ltd.

The aim of this work is to investigate the physical mechanisms behind the write/erase and retention performances of band gap engineering (BE) layers used as tunnel oxide in charge trap memory stack. The investigation of the BE layers alone will be completed with the analyses of its integration within a TANOS (TaN/Alumina/Nitride/Oxide/Silicon) stack, pointing out the correlation between electrical performance and reliability limits.Good write/erase/retention performances can be achieved with BE tunnel oxide by using silicon nitride layer integrated in SiO2-Si3N4-SiO2 stack, as long as all different mechanisms are taken into account in optimizing stack composition: hole injection which improves erase efficiency, charge trapping and detrapping from the thin silicon nitride which causes program instabilities and initial charge loss which does not significantly impact long term retention. All these phenomena make very crucial the BE tunnel process control and difficult its use for multi-level application. (C) 2011 Elsevier B.V. All rights reserved.

AbstractPurpose: Altered expression of cell cycle/apoptosis key regulators may promote tumor progression, reflect secondary genetic/epigenetic events, and impair the effectiveness of therapy. Their expression pattern might then identify gastrointestinal stromal tumor (GIST) patient subgroups with different response to imatinib and elucidate novel therapeutic targets.Experimental Design: Immunohistochemical evaluation of expression of p53, p16, p21, CHK2, CCND1, BCL2, CDK4, and MDM2 was done on 353 histologically validated GIST patients enrolled into a European/Australasian phase III trial. TP53 was screened for mutations in cases with presumptive nonfunctional protein; that is, high p53 and low expression of the two downstream molecules p21 and MDM2. Results were correlated with clinicopathologic data, KIT/PDGFRA mutation status, and imatinib dosage.Results: Frequent impaired expression was found for BCL2 (78%), CHK2 (53%), p53 (50%), and p16 (47%). Stomach-originating GISTs showed significantly lower expression of p21, p16, and BCL2. KIT/PDGFRA wild-type GISTs had significant lower expression of CDK4. Eighty-eight percent of the high p53 expressers show low downstream target activation, indicating a nonfunctional p53 route. Of these high p53 expressers, 16.4% harbor a detectable TP53 mutation. Multivariate analysis, including previously identified markers, showed an independent effect of p53 and p16 on progression-free survival (PFS). Patients with high level of CHK2 and p21 showed significantly better PFS upon a high-dose regimen.Conclusions: Impaired p53, p16, BCL2, and CHK2 expression is common in advanced GISTs. Distinct patterns of expression correlate with tumor site, genotype, and PFS. Cell cycle/apoptosis maintenance is instrumental for optimal response to imatinib.

0P1-1 THE ACCURACY OF IMPRINT CYTOLOGY OF SENTINEL LYMPH NODE IN BREAST CANCER: AN ANALYSIS OF CAUSES OF DISCREPANCIES Peir-In Liang, Ming-Yuan Lee, Ben-Long Yu, Chii-Ming Chen, Dong-Ling You, Christopher K-J Lin 1 Department of Pathology and Laboratory Services, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan 2 Department of General Surgery, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan 3 Department of Nuclear Medicine, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan 4 Department of Radiology, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan

The conversion of tricloroethylene (TCE) in the presence of water (i.e. in the conditions of steam reforming) has been investigated in a flow reactor. The catalyst was an H-Y zeolite (SiO2/ Al2O3 = 5,9). Some experiments with ferrierite have also been done for comparison. IR experiments have been performed in order to have information on the reaction mechanism and on the catalyst stability. With 1000 ppm feed TCE concentration, stoichiometric water and oxygen excess, TCE can be totally converted to COx and HCl at 850 K or above. In these conditions the reaction kinetics is governed by the chemical step and deactivation phenomena are slow. With 10000 ppm. TCE the reaction can be complete near 700 K. However, the reaction rate is in these conditions affected by pore diffusion, which becomes determinant at contact times higher than 0.15 s. In the absence of oxygen fast deactivation phenomena occur by coking and. catalyst dealumination.