A systematic AFM study of gold films deposited on mica substrates under a range of selected conditions reveals the evolution of the surface morphology of the films as a function of growth temperature, film thickness, and deposition rate. Scaling analysis shows that the growth behaviour of the surfaces of these films can be considered as self-affine fractals. The observed topography follows island-type (3D) growth processes in the majority of cases with a roughness exponent, α, in the range 0.24-0.75, or quasi-2D island growth in the remainder with α = 1.19 or 1.45. In the latter cases, however, the two gold films grown under the particular conditions used reflect typical growth models expressing a high roughness exponent, well consistent with theoretical prediction.

X-ray photoelectron spectroscopy (XPS) has been used to characterize the composition of air-cleaved mica surfaces before and after treatment under a range of different conditions in the argon rf plasma discharge. The changes in the composition of the processed surfaces that have been identified are found to depend strongly on the plasma etching parameters used. When etching was conducted at relatively high power levels ( W), the XPS data demonstrate that the mica surfaces examined have a significant accumulation therein of the heavier elements present, namely aluminium and silicon, whereas the oxygen component on the surface is decreased dramatically. However, no obvious changes in the chemical states of the elements contained in the mica were found for the sample surfaces processed under these conditions. Similar phenomena were also observed when the plasma etching was conducted at higher gas pressures or over prolonged etching times. The various phenomena observed are attributed mainly to the disorganization of the mica surface during etching, namely sputtering followed by re-deposition of the component elements, with loss of oxygen from the surface becoming apparent when the etching parameters were changed as indicated. A relatively high carbon content measured by XPS is always observed on the plasma-etched mica surfaces for which a low silicon content is usually found. The reasons for this behaviour are discussed. The oxygen deficit observed on the argon plasma-etched mica surfaces may be even more significant if one makes allowance for the possible contribution that surface-adsorbed species containing oxygen can make to the oxygen signal.

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in gastric cancer patients treated with oxaliplatin-based adjuvant chemotherapy (P < 0.05).CONCLUSION: ERCC1 codon 118 polymorphism has no significant impact on ERCC1 mRNA expression, and the intratumoral ERCC1 mRNA level but not codon 118 polymorphism may be a useful predictive parameter for the relapse and survival of gastric cancer patients receiving oxaliplatin-based adjuvant chemotherapy. INTRODUCTIONIn China, gastric cancer is the leading cause of cancer deaths, accounting for nearly one-fourth of all cancer deaths. Surgery is the primary modality for managing early-stage and locally-advanced disease. However, even after gastrectomy, the majority of patients develop local or distant recurrence [1] . Adjuvant chemotherapy for gastric cancer has been under clinical investigation for more than four decades. Fluoropyrimidines, platinumdrugs and taxanes were shown to be effective in the treatment of gastric cancer. However, the response rates of these drugs or their combinations were less than 50% [2,3] . There is no standard regimen for postoperative treatment at the moment. Having an effective assay to predict the response to a given chemotherapeutic protocol beforehand would greatly enhance the success rate as well as the life quality of the patients.The nucleotide excision repair (NER) system plays a significant role in repairing a variety of distorting Abstract AIM: To determine the influence of excision repair cross complementing group 1 (ERCC1 ) codon 118 polymorphism and mRNA level on the clinical outcome of gastric cancer patients treated with oxaliplatin-based adjuvant chemotherapy. METHODS: Eighty-nine gastric cancer patients treated with oxalipatin-based adjuvant chemotherapy were included in this study. ERCC1 codon 118 C/T polymorphism was tested by polymerase chain reaction-ligation detection reaction (PCR-LDR) method in peripheral blood lymphocytes of those patients; and the intratumoral ERCC1 mRNA expression was measured using reverse transcription PCR in 62 patients whose tumor tissue specimens were available. RESULTS: No significant relationship was found between ERCC1 codon 118 polymorphism and ERCC1 mRNA level. The median relapse-free and overall survival period was 20.1 mo and 28.4 mo, respectively. The relapse-free and overall survivals in patients with low levels of ERCC1 mRNA were significantly longer than those in patients with high levels (P < 0.05), while there was no significant association found between ERCC1 118 genotypes and the disease prognosis. Multivariate analysis also showed that ERCC1 mRNA level was a potential predictor for relapse and survival

The effect of imaging environments and imaging parameters on the lattice-resolved AFM images of mica surfaces has been investigated. As the force-contrast of an AFM image is determined by the tip - surface interactions, the appearance of the AFM images changes accordingly when the force applied to the tip, the scanning direction, or the imaging liquid used is changed. All these factors can modify the details of the tip - surface contact situation so as to affect both the vertical repulsive and the direction-dependent frictional forces, resulting in the superposition of local distortions and other anomalies onto the atomically resolved images of the mica surface.